CA2236504A1 - Fluid-absorbing polymers, process for the preparation and use thereof - Google Patents
Fluid-absorbing polymers, process for the preparation and use thereof Download PDFInfo
- Publication number
- CA2236504A1 CA2236504A1 CA002236504A CA2236504A CA2236504A1 CA 2236504 A1 CA2236504 A1 CA 2236504A1 CA 002236504 A CA002236504 A CA 002236504A CA 2236504 A CA2236504 A CA 2236504A CA 2236504 A1 CA2236504 A1 CA 2236504A1
- Authority
- CA
- Canada
- Prior art keywords
- cross
- fact
- polymer
- weight
- polymers
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F290/00—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups
- C08F290/02—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups on to polymers modified by introduction of unsaturated end groups
- C08F290/06—Polymers provided for in subclass C08G
- C08F290/062—Polyethers
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L15/00—Chemical aspects of, or use of materials for, bandages, dressings or absorbent pads
- A61L15/16—Bandages, dressings or absorbent pads for physiological fluids such as urine or blood, e.g. sanitary towels, tampons
- A61L15/42—Use of materials characterised by their function or physical properties
- A61L15/60—Liquid-swellable gel-forming materials, e.g. super-absorbents
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F251/00—Macromolecular compounds obtained by polymerising monomers on to polysaccharides or derivatives thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F261/00—Macromolecular compounds obtained by polymerising monomers on to polymers of oxygen-containing monomers as defined in group C08F16/00
- C08F261/02—Macromolecular compounds obtained by polymerising monomers on to polymers of oxygen-containing monomers as defined in group C08F16/00 on to polymers of unsaturated alcohols
- C08F261/04—Macromolecular compounds obtained by polymerising monomers on to polymers of oxygen-containing monomers as defined in group C08F16/00 on to polymers of unsaturated alcohols on to polymers of vinyl alcohol
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F267/00—Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated polycarboxylic acids or derivatives thereof as defined in group C08F22/00
- C08F267/06—Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated polycarboxylic acids or derivatives thereof as defined in group C08F22/00 on to polymers of esters
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
- H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
- H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Dispersion Chemistry (AREA)
- Hematology (AREA)
- Physics & Mathematics (AREA)
- Materials Engineering (AREA)
- Epidemiology (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Absorbent Articles And Supports Therefor (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
- Graft Or Block Polymers (AREA)
Abstract
The invention relates to super-absorbent, cross-linked polymerisates for aqueous liquids which comprise monomers carrying partially neutralised, monoethylenically unsaturated acid groups, optionally other monomers copolymerisable therewith and optionally polymers suitable as a graft base. Said polymerisates can be obtained using a cross-linkage/ monomer combination from I. CH2=CHR6-CO-(OCHR3-CHR3)zO-CH2-CHR6=CH2, II. CH2=CHR6-R5-(OCHR3-CHR3)vOR4, III. R1-¢O(CHR3-CHR3O)u-CO-R2!x, and/or diallyl amine or triallyl amine and /or bisacrylamides, where R1 is a polyvalent C2-10-alkyl, R2 is a linear or branched C2-10 alkenyl, R3 is H, CH3, C2H5, R4 is H, linear or branched C1-10 alkyl, R5 is CO, CH2, R6 is H, CH3, x is 2-6, u is 0-15, v is 145.
Description
CA 02236504 1998-0~-20 Fluid-absorbing Polymers, Processes used in their Production and their Application The invention concerns superabsorbing polymers for watery liquids, processes used in their produdion and their ap,~lic-'ion. The polymers, based on monomers containing carboxylate groups and obtained by a special co",~..,alion of cross-linking agents and other co",onon~ers, show a co,nbi.,dlion of properties never aUained before with regard to absGr~tion rate, high retention at high absGr~liGn under pressure, low soluble content and good permeability of the gel layer for watery liquids under pressure load and stable surface cross-linkage.
Superabsorbent polymers are water-insoluble cross-linked polymers which are capable through swelling and with the fo.",~lion of hydrogels of absorbing large quantities of watery liquids and body fluids such as urine and blood and of retaining the absorbed amount of fluid under a certain press'ure. RecAuse of these typical absor,l,lion properties the polymers are mostly used for integrating into sanitary articles such as diapers and ladies' napkins.
Commercially available superabsorbent polymers are mainly cross-linked polyacrylic acids or cross-linked starch/acrylic acid graft copolymers in which the carboxyl groups are partly neutralized with sodium or potassium ions.
The produdion of superabsorbent polymers is mainly carried out by polymerisation of watery solutions of mixtures of partly-neutralked acrylic acid and cross-linking agent to a polymer gel which is mechan.~~lly broken up into small pieces, dried and then ground to a certain particle size. Alternatively, polymer powders can also be obtained by inverse suspension polymerisation in which the watery monomer phase in an oil phase, consisting, for example, of cyclohexane, is suspended with auxiliary agents and then polymerised. By azeotropic distillation the water contained in the polymer droplets is removed and the polymer particles then isolated by filtering off from the oil phase.
In the course of the continued technical development of superabsorbing polymers the demands made on these produds has changed markedly over the years. While during the development of the superabsorbers only the very high swelling capacHy on contad with liquid was of prime importance at first, it later turned out that not only the amount of absorbed liquid was important, but allso the firmness of the swollen gel. Retention on the one hand and gel firmness on the other are, however, opposing properties, as is known from US 3 247 171 and US Re 32,649. This means that polymers with a particularly high retention show only a low level of firmness of the swollen gel, with the result that the gel can be deformed under an applied pressure (e.g. body pressure) and further liquid absorption prevented. Therefore a balance between retention and gel strength has to be striven for so that in use fluid absorption can also take place against an applied pressure. This specific absorption characteristic is termed absorption under pressure in EP 339 461.
The method of measuring the fluid take-up under pressure (AUL) is carried out under various load;. In the course of the increased demands on superabsorbers H has turned out that the original test load of 21 g/cm2 (0.3 psi) no longer measures the desired quality standard as required for incontinence produds or for diaper designs with low fluff content and high amounts of superabsorber. Accordingly pressure loads are measured today at 42 g/cm2 (0.6 psi) and preferably at 63 g/cm2 (0.9 psi).
The increasing tendency to design sanitary articles ever smaller and thinner can only be fulfilled by reducing the voluminous fluff component in the diaper and at the same time increasing the proportion of supe,dbsoll,er. Here the superabsorber has to take over additional tasks with regard to fluid absorption and transport which were previously carried out by the fluff.
CA 02236~04 1998-0~-20 The c:haraclteristics of the superabsorbers can be improved by the process of subsequent surface cross-linkage, in particular their fluid absor,.lion under pressure, as the well-known phenomenon of "gel blocking" is suppressed, in which swollen polymer particles stick together and prevent any further absor~ tion and distribution of fluid in the diaper. During the subsequent cross-linking process the carboxyl groups of the polymer molecules are cross-linked on the surface of the super-absorber particles with cross-linking agents at a raised temperature. Among other agents, multivalent metal salts, glycidyl compounds, polyols, polyepoxides, polyamines, alkylene carbonates and polyethylene glycols are used. Subsequent cross-linking can be carried out several times. It is clear from the patent literature that the increased fluid absorption under pressure is associated with a marked reduction in retention. There is therefore a requirement for superabsorber starting products which show a less marked drop in the retention values in subsequent cross-linking. Moreover, N has not been possible so far to fix the surface cross-linkage permanently to the polymer backbone. For this reason, most of the effects obtained by surfalce cross-linking are destroyed again by mechanical actions exerted on the absorber.
For the processing of the superabsorbers various screening r~aclions are used, depending on the application, e.g. for diapers between 100 and 800,u, for cable insulation under 200~u. This means that in the case of the application in cables the fine constituents of the superabsorbers are of advantage because of their tendency to gel blocking, as this blocks off the water penetrating the cable. In the diaper this effect is not desired as n impedes the absorption and distribution of fluid, and so larger screening fractions are selected.
Besides a high degree of retention and fluid absorption under pressure supe~bsc,rl,ers have to contain low soluble constituents which arise due to incomplete cross-linking during the polymerization reaction and which are not fully retained in the body of the polymer when applied.
This finally leads to a reduction in the capacity of the superabsorber to absorb and distribute fluid in the diaper. The limiting values quoted for low soluble constituents, for example, in the US Re.
32,649 are 7.5% afler 1 hour and 17% after 16 hours. Compared to the product properties desired by present-day producers of hygiene articles, these limiting values for the soluble constituents are far too high.
The optimization of application properties of the superabsorbing polymers was carried out in the past mainly by varying the type and amount of cross-linking agent, by the pH value during polymerkation and by after-treatment of the polymer particles in the form of a coating or subsequent surface cross-linking. So far, however, H has not been possible to make available any superabsorber combining the properties of high retention, high AUL (63 g/cm2, 0.9 psi) and low soluble contents and at the same time high permeabiliiy in the gel layer for watery liquids under pressure load, high rate of absorption and lasting surface cross-linkage.
The basis of WO 94/09043 is the problem of developing new superabsorbing polymers with increased absorption capacity for watery liquids, even under pressure. It describes the solution to this problem as double cross-linked superabsorbers whose first stage of production is cross-linking during polymerization with methylene bisacrylamide, bis(acryla"~.do)acetic acid, allyl acrylate, allyl methacrylate, esters or amides with terminal vinyl and allyl functions or highly ethoxylated trimethylol propane triacrylate and as a second stage the coating of the resuHing polylmer particles on the surface with a cross-linking agent, fe"~wcd by cross-linking. In this process, which is not new, the preferred surface cross-linking agents are polyhydroxy compounds which are applied together with water or water/solvent mixtures and caused to react at raised temperatures (175 - 230~C) after the moisture in the polymer gel of the first stage has been at least partly removed.
By ihe combination of one of the above-mentioned primary cross-linking agents with the secondary surface cross-linking agenis unique product properties are said to be obtained with regalrd to retention and fluid absorption under pressure, making it possible for them to be used in hygiene articles in which the absorbing polymers have to take up considerable amounts of tluid and retain them even under pressure. When the resuHs of the trials are examined it is noticeable that the polymers show a marked improvement in their properties simply by being stored at a high CA 02236~04 1998-0~-20 temperature without the addition of a subsequent cross-linking agent. Subsequent cross-linking produces a further increase in fluid absorption under pressure at 42 g/cm2 (0.6 psi). These AUL
values are then in a range between 10 and 26 9/9, depending on the type, whereby the products with the highest AUL values only reach absorption values of 30 g/g. Absorption values of over 30 g/g are, as example 3B (absor~,lion 35 g/g and AUL 16.5 g/g) shows, only possible at the expense of the AUL at 42 g/cm2 (0.6 psi). This makes it clear that the products with the special cross-linking combination contained in WO 94/09043 in no way meets the high demands made today on such cross-linked polymers, i.e. the peak values measured therein for 42 g/cm2 (0.6 psi) are required today for a higher load at 63 g/cm2 (0.9 psi), combined with absorption values of markedly greater than 30 g/g.
WO 93/21237 describes superabsorbent polymers which are cross-linked with unsaturated esters of polyalkyl glycols and which, through a subsequent heating process, achieve an improvement in prope'rties with regard to retention and liquid absorption under a low pressure of 21 g/cm2 (0.3 psi) of up to 25 g/g. Ethoxylated t,imetl,~lol propane triacrylate is the preferred cross-linking agent, whereby the number of EO units per polyglycol chain can be betwe~en 2 and 7. According to this paper the use of non- or only slightly ethoxylated trimethylol propane triacrylate leads to considerably worse properties of the superabsorber which is cross-linked with it. Analagous to the polymers in WO 94/09043 the products described here also do not fulfil the demands placed today on absorption under a higher pressure at 63 g/cm2 (0.9 psi). In diagram 13 on page 8/8 of WO '33/21237, which shows the process of fluid absorl,lion under pressure for various pressure loads, the weakness of the polymers described there can be seen quite clearly, whose measured values of approximately 18 g/g in the interesting pressure load range of 63 g/cm2 (0.9 psi) are totally uns~ .facory. This all the more so when the measured values were obtained on a very unusual screening rractiOn of 300 - 600,um which per se results in higher measured values than the screening fraction of 150 - 8001Jm usual in the field.
US Re. 32,649 deals with the production of non-grafted superabsorbent polymers with a high gel volume, high gel strength, measured via the shear modulus and low solwble contents. The gel volume should be at least 20 9/9 and the maximum value of the soluble components, measured afler 1 hour, should not exceed 7.5% and in the state of equilibrium after 16 hours be no more than 17%. Preferably the polymers should be polymerked in a low watery starting concentration of 8 lo 24 % by weight from acrylic acid which is not neutralked, cross-linkage preferably takes place with N,N'-methylene bisacrylamide, trimethylol propane triacrylate or triallylamine. This is followed by crushing, neutralization, grinding and drying.
The production process described in Re 32,649 contains important drawbacks in the method. On the one hand the low starting concenlr~lion and the subsequent heating of the polymer gel over several hours means that the space-time yield is low, and on the other hand the step of subsequent neutralization of the solid polymer gel is technically very time-consuming and cannot be c arried out to the same quality as neutralkation in the preceding solution can be. Polymer gels neutralized subsequently are, as a rule, not neutralked consistently and often di~co'cred due to the irregular distribution of alkali. As a consequence of the uneven neutralization strong fluctuations in the quality of the product can arise.
EP 1390 077 describes superabsorbers having an improved breaking strength by using polye!thylene glycols and derivatives, such as methoxypolyethylene glycol methacrylates used as additives or comonomers. The superabsorbers are distinguished by the fact that there are less partic:les in the range < 5 ,um in a grinding test when compared with a reference product. There are no statements with respect to the swelling properties of the superabsorbers after mechanical load. The described superabsorbers are neither produced with special pre~ross-linking agents nor with subsequent surface cross-linking agents. The indicated absorptions under a pressure of at least 17 g/g, preferably > 20 g/g (AUL) merely relate to an extremely low load of about 20 g/cmZ and - measured against the art - are not in an acceptable region. For cluite a long time, prior art superabsorbers provide higher absorptions under a higher pressure (63 g/cm2) of > 20 g/g.
On the other hand, using polyethylene glycols to dedust superabsorbers is known.
CA 02236~04 1998-0~-20 In W~ 94/22940 superabsorbent polymers with a small dust component are described which arise due to a surface coating with polyol or polyethylene glycol and which show liquid absorption under low pressure at 21 g/cm2 (0.3 psi) of ~ 20 9/9. The treatment of superabsorbers with such substances has already been described in WO 93/21237 (page 12, line 15). This version showing improved abrasion and reduced dust requires, however, an additional step in the manufacturing process.
At present there are no prior art documents concerning the manufacture of superabsorbers with the desired ~m~.ndtion of properties of high permeability for watery liquids, stable surface cross-linkage, high retention, high absorption rate, pressure-resistant hydrogel and a low soluble component.
Low soluble cG"~ponents are also a precondition for superabsorbers which have to show a practical swelling pressure over a long time. If the amount of soluble contents is over 12% the superabsorL,er can no longer, after being subjected to pressure for 16 hours, in a diaper for example, store the amount of fluid required for application technological reasons.
The permeability in the layer (i.e., in x,y-direction) of the absorbent article comprising the superabsorber particularly gains in il"po,lance when constructions are used having an ever reduc:ing fluff amount with a simultaneously increasing superabsorber amount. This additionally gains in importance if the liquid distribution has to take place under a pressure of 50 glcm2, for exarnple.
A suitable method to determine the permeability of a gel layer in x,y-direction under pressure is the method of determining the absorption under pressure through a size-reduced aperture in the bottom of a so-called MP-cylinder unit.
The AAP-cylinder unit is described in EP 640 330 on page 14 (Absorption against Pressure test).
Superabsorbent polymers which are to meet today's state of the art with respect to absorbent articl~ construction, must support the liquid transport in x,y-direction, i.e., within the gel layer, such that highest possible absorption values are achieved in the mentioned measuring method. The measured values are then ~alcu~ted against the respective absorption against pressure at the same load (20 gJcm2 or 50 glcm2) and are expressed as percentage absorption. The demands placed on diapers comprising larger amounts of superabsorber require values in the range of > 50'~b; for the surface-reduced AAP-value at least 15 9/9 must be achieved.
The object of the present invention is to provide new polymers and a process for making them.
These polymers were to be used as superabsorbers in diapers or other technical applications and were to have an improved combination of properties with regard to retention, fluid absorption under pressure at 63 g/cm2 (0.9 psi) and soluble components, and which, due to their polymer composition, were to have an efficient and lasting surface cross-linkage and, due to their permeability, permit a good liquid distribution in swollen condition even under pressure (50 g/cm2).
Moreover, the superabsorbers should possess a high suction rate and a high swelling pressure.
Surprisingly it was found that cross-linked polymers absorbing watery liquids, built-up of partially neutralized monomers having monoethylenically unsaturated acid groups and optionally further monomers copolymerkable therewith as well as optional water-soluble polymers suitable as graft basis, that are produced using a cross-linker combination of 1. CH2=CH R6-CO-(OCH R3-CH R3)zO-CH2-CH R5=CH2 Il. CH2=CHR6-R5-(oCHR3-CHR3)VoR4 Ill. R'-[o(CHR3-CHR3O)u-Co-R2]x~ and/or di- or triallylamine and/or bisacrylamide with R': multivalent C2-10-alkyl R2: linear or branched C2-1 0-alkenyl CA 02236~04 1998-0~-20 R3: H, CH3, C2H5 R4: H, linear or b;anched C1-10-alkyl, R5: CO, CH2 R8: H, CH3, x: 2-~i u: 0-~15 v: 1 ~15 z: 3-~'0 and are then subjected to surface cross-linkage have a retention of greater than 30 9/9 and a liquid absorption under pressure at 63 g/cm2 (AUL 0.9 psi) of greater than 20 9/9, and their soluble contents after 1 hour are less than 6.5% and aRer 16 hours less than 10%, and their permeability within the gel layer permHs to use at least 50%-test (Absor~,lion against Pressure with a suction surface reduced by x~/0) wHh at least 15 9/9, preferably at least 20 9/9 AAP50-AX.
Due lo the preferably at least 60% of absorption capacity under a load of 50 g/cm2 in the MP-Ax.polymer structure, which is achieved according to the present invention, an improved and lasting cross-linkage between the polymer and the surface cross-linking agent takes place. This is shou~n in the fact that the AUL (63 9/cm7, after a loading test to determine the stabilHy of the surface cross-linkage, still has values of greater than 18 9/9, and this suggest.C an extraordinarily stable surface cross-linkage and an extremely thorough reaction with the surface cross-linking agent.
The c ross-linking agents thus invented according to formula I contain a (meth)allyl function and a (meth)acrylic acid ester function as well as a hydrophilic chain situated between these two funclions consisting of at least three, but preferably five to twenty ethylene oxide units. The used of mixed ethylene oxide/propylene oxide chains, which can be produced as random or block copolymers, is possible. The solubility of the cross-linking agent in the monomer solution to be polyrnerked can be adjusted by the relationship of EO/PO units. The cross-linkers can be produced, for example, by esterification of alkoxylated allyl alcohol with (meth)acrylic acid. In the newly invented cross-linking agents there may be residues of starting co."ponents to be found due to the manufacturing process which do not, however, have a negative effect on the proplerties of the superabsorber. The cross-linking agents according to formula I or their mixtures are used in a ratio of 0-1.0% by weight or preferably 0.05-0.6% by weight, or even better 0.1-0.4~/t, by weight with regard to the whole monomers.
The newly-invented monomers to be used wdh the cross-linkers according to formula ll are preferably (meth)acrylic acid ester or (meth)allyl alcohol ether from polyalkylene glycols. A
preferred type is the polyoxyalkylene glycol chain with a terminal alkyl residue. The C number in ~ the alkyl residue is in the range 1-10, preferably in the range 1-7, more preferably in the range 1-4. V\lhen choosing the alkyl group attention should be paid to the sulra~dnl character of the monomer and, if necessary, the alkyl residue has to be adjusted accor.li.lgly in order to avoid the formation of foam which can have a disruptive effect in some polymerkation processes. The polyoxyalkylene glycol chain is preferably composed of ethylene oxide andlor propylene oxide, whereby the solubility of the cross-linker in the watery monomer solution can be adjusted by the ratio of EO/P0. The content of alkyl glycol units in the chain is in the range 1-45, preferably in the range 1-30, and at best in the range 5-25. The monomers according to formula ll or their mixtures are used at up to 0.1-10% by weight, preferably at 0.5-5% by weight, or more preferably at 1.0-3.5~~, by weight with regard to the whole monomers. The monomers mentioned in ll are commercially available, e.g. the methyl polyethylene glycol methacrylates from the firm Interorgana under the name Bisomer MPEG(x)MA (x=350,1000, 2000).
According to this invention the cross-linking agents to be used accordi"g to formula lll are esters from polyhydroxy compounds with unsaturated carboxylic acids, a preferred form of which are alkoxylated. It is preferred to use C3-6-polyhydroxy compounds wHh 24 hydro~yl groups as starting compounds for the synthesis of such cross-linkers such as l,imell,ylol propane, glycerine, pentaerythritol, 1,3-propandiol, propylene glycol or 1,4 butandiol. If before esterification alkoxylation of the alcohol occurs, it is preferable to use ethylene oxide. It is preferable to use CA 02236~04 1998-0~-20 alkoxylated polyhydroxy compounds from u=1, preferably from u=3. It is preferable to use (meth)acrylic acid as the acidic ~",ponent. In a further preferred form of the cross-linking agent lll polyethylene glycol di(meth)acrylate is used. In a particularly preferred form of cross-linking agent lll di- or triallylamine and/or N,N-methylenebisacrylamide and/or bisacrylamido acetic acid are used. Also, mixtures of the last-mentioned cross-linking agents with the previously mentioned carboxylic acid esters of the polyhydroxy compounds exhibit an excellent activity.The cross-linkers in formula lll or their mixtures are used at 0.01-1.0 % by weight, preferably at 0.05 - 0.6 %
by weight, more preferably 0.05 - 0.3 % by weight with regard to the monomers. According to this invention the cross-linkers according to lll are partly available commercially, e.g. trimethylol propalne oxethylate triacrylate from the firm Cray Valley under the name Sartomer SR 415 (20 EO), Craynor 435 (15 EO), Sartomer RO 208 (9 EO), Sartomer 454 (3 EO), and pentaerythritol oxethylate tetraacrylate under the name Craynor SR 494 (5 EO) and Servocure RTT 192 (5 EO) from the firm Servo Delden BV, glycerine ethoxylate triacrylate (5,5 EO3 under the name Sartomer 921 anci glycerine propoxylate triacrylate under the name Sartomer 9021 from the firm Cray Valley, as well as polyethylene glycol-400-diacrylate as Craynor SR 344 and polyethylene glycol~00-dimethacrylate as Craynor SR 252 from the firm Cray Valley.
Surprisingly it turned out that with the new cross-linker/monomer combination mutual solubilkation of the cross-linker components, both soluble and insoluble in the watery monomer solution, is poss;~le. This also makes the use of cross-linking agents possible which cannot norm,~lly be used, or only in extremely limited amounts, due to their poor solubility.
In a further favored method the use of mixtures of highly and slightly alkoxylated cross-linkers/monomers according to 1, ll and lll in the cross-linking of the new superabsorbers has proved its worth.
The newly invented polymer for absorbing watery liquids is obtained by polymerization of ethylenically unsaturated monomers bearing acid groups, for example from acrylic acid, meth,acrylic acid, vinyl acetic acid, maleic acid, 2-acrylamido-2-methyl propane sulfonic acid, vinyl sulfonic acid, (methyl)allyl sulfonic acid or their mixtures in the presence of the cross-linkerlmonomer cc"~ lion of the components 1, ll and lll. The ratio of these acidic monomers in the monomer mixture is 55 - 99 % by weight.
The acidic monomers are at least 25 % mole, preferably 50 % mole, more preferably 50 to 80%
mole neutralized and are present, for example, as sodium, potassium or arr,r,lonium salt or their mixtures. Neutralization is carried out either by the addition of the corresponding alkali or amm~nium hydroxides or with the corresponding carbonates or hydrogen carbonates.
Optionally, the newly invented polymers can contain further comonoi"ers in order to modify their properties. Such co,-lononlers can be, for example, (meth)acrylamide, (meth)acryl nitrile, vinyl pyrrolidone, vinyl acetamide, hydroxy ethyl acrylate, alkyl aminoalkyl (meth)acrylates, alkyl amino-propyl acryla,l,i~es, acryl amidopropyl trimethyl ammonium chloride or their mixtures. Such comonomers should not exceed a proportion of 40 % by weight as they may negatively affect the swelling capacity of the superabsorber.
The newly invented polymers may contain water-soluble polymers as a grafl basis in quant-~ies of up to 30 % by weight. These include, among others, partly or fully saponified polyvinyl alcohols, starch or starch derivatives, cellulose or cellulose derivatives, polyacrylic acids, polyglycols or their mixtures. The molecular weights of the polymers added as a graft basis have to be adapted to the polymerization conditions. It may be necessary, for example in the case of a watery solution polymerization, for reasons of the viscosity of the polymer solution, to use only low or medium molecular polymers, whereas in suspension polymerization this factor plays a minor role.
Besides polymers which are obtained by cross-linking polymerization of partly-neutralized acrylic acid, it is preferable to use those containing additional proportions of graft polymerked starch or polyvinyl alcohol.
CA 02236~04 1998-0~-20 The production of the newiy invented superabsorber takes place principally according to two methods:
According to the first method the partly neutralized acrylic acid in a watery solution in the prese'nce of the cross-linker/monomer combination of 1, ll and lll as well as any necess~ry polymer additives is transforrned into a gel by radical polymerization which is then reduced in size, dried, ground, re-cross-linked and sieved down to the desired particle ske. The solution polymerkation can be carried out continuously or discontinuously. The patent literature contains a broacl spectrum of possible variations wdh regard to the concenl,dlion ratios, temperatures, type and quantity of the initiators as well as a multitude of re-cross-linking possibilities. Typical processes are described in the fo" ~ 9 patent specilicalions, which are herewith intended to become a part of the newly invented manufacturing process: US 4 076 663, US 4 286 082, DE 27 06 135, DE 35 03 458, DE 40 20 780, DE 42 44 548, DE 43 23 001, DE 43 33 056, DE 44 18 818.
The second method includes the inverse suspension and emulsion polymerization process. In these processes a watery, partly neutralked acrylic acid solution is dispersed with the help of protective ~"cids and/or emulsifiers in a hydrophobic, organic solvent and polymerization started by radical initiators. The cross-linking agents are either dissolvcd in the monomer solution and are doseld with this together or separately, and if necessary added subsequently. The addition of any polyrner grafl bases which may be present is carried out via the monomer solution or by direct additon into the oil phase. Afler the end of the polymerization the water is removed azeotropically from the reaction mixture and the polymer product filtered off. Surface cross-linkage of the polyrner particles can be carried out in the suspension as well as subsequently on the isolated polyrlner powder. The principle of the procedure is described, for example, in patent specifications US 43 40 706, DE 37 13 601, DE 28 40 010 and should be considered as part of the newly invented manufacturing process.
The addition of the subsequent cross-linking agent is oflen carried out to advantage in the form of a solution in water, organic solvents or their mixtures, in particular when small quantities of re-cross-linking agent are used. Suitable mixing machines for the application of the re-cross-linking agent are, for example, Patterson-Kelly mixer, DRAIS eddy mixer, Lodige mixer, Ruberg mixer, screw mixer, pan mixer and fluidked bed mixer as well as continuously working vertical mixers in which the powder is mixed at a high frequency by means of rotating knives (Schugi mixer). Afler the re-cross-linking agent has been mixed with the pre-cross-linked polymer heating is carried out up to temperatures of 120 to 250~C, preferably up to 135 to 200~C, more preferably up to 150 to 185~lv in order to carry out the re-cross-linking reaction. The length of the subsequent heating is limited by the point at which the desired set of properties of the superabsorber is destroyed again as a result of heat damage.
The newly invented superabsorbers show an unprecedented combination of favorable properties.
Due to the positive influence of the cross-linker/comonomer combination the high retention of the polyrner present before re-cross-linking is stabilized to such an extent that after the surface re-cross-linking a retention of over 30 g/g is still measured.
Afler the absorption of fluid, whose rate is less than 40 seconds, preferably less than 35 seconds, more preferably less than 30 seconds, the swollen gel particles stand out due to their dry handle, i.e. tlhey do not possess the undesired wet, sticky surface which arises with insufficient cross-linking/re-cross-linking. In addition, together with the high retention the soluble contents afler 1 hour are less than 6.5 %, preferably less than 5 % or afler 16 hours less than 10 %, preferably less than 8 %. The liquid absorption under a pressure (AUL) of 63 g/cm2 (0.9 psi) is greater than 20 9/'9, preferably greater than 23 g/g, more preferably greater than 25 g/g.
Due to the cross-linker/monomer combination according to the present invention the superabsorbers obtain an excellent permeability for liquids in swollen condition under load. The cross-linker/monomer combination according to the present invention provides an efficient and lasting surface cross-linkage of the polymer. This makes it possible to produce superabsorbers CA 02236~04 1998-0~-20 whichl, after a loading test to examine the stability of surface cross-linkage (SDOV = "St~ at der Oberl1achen_ernekungn), still have AUL values (63 g/cm2) of at least 18 9/9, preferably of greater than ,20 g/g, and most preferably of greater than 22 9/9.
The swelling pressure of the newly-invented polymers is high and after 20 minutes is at least 600 g, preferably at least 800 9, more preferably greater than 900 9.
The newly-invented hydrophilic superabsorbers are used everywhere where watery liquids have to be absorbed. This includes, for example, the generally known ~FFI ~ions for superabsorbers in hygiene articles in the form of diapers for small children and incontinence products for adults, in ladies' napkins, in plasters, in food packagings, in the field of agriculture for plant raising, in cable insulation, in absorbent layers made of paper, water-soluble polymers and thel"~opla~lic man-made materials and foams as well as car,ier~ for active subslances with the task of delayed release to the environment.
In the following examples the manufacture and properties of the newly-invented polymers are explalined and in the chapter on testing methods the regulations governing the determination of the properties of superabsorbers are described.
Test Methods 1. R~!tention The retention is measured according to the method described in EP 514 724 (page 4, lines 6-22).
Superabsorbent polymers are water-insoluble cross-linked polymers which are capable through swelling and with the fo.",~lion of hydrogels of absorbing large quantities of watery liquids and body fluids such as urine and blood and of retaining the absorbed amount of fluid under a certain press'ure. RecAuse of these typical absor,l,lion properties the polymers are mostly used for integrating into sanitary articles such as diapers and ladies' napkins.
Commercially available superabsorbent polymers are mainly cross-linked polyacrylic acids or cross-linked starch/acrylic acid graft copolymers in which the carboxyl groups are partly neutralized with sodium or potassium ions.
The produdion of superabsorbent polymers is mainly carried out by polymerisation of watery solutions of mixtures of partly-neutralked acrylic acid and cross-linking agent to a polymer gel which is mechan.~~lly broken up into small pieces, dried and then ground to a certain particle size. Alternatively, polymer powders can also be obtained by inverse suspension polymerisation in which the watery monomer phase in an oil phase, consisting, for example, of cyclohexane, is suspended with auxiliary agents and then polymerised. By azeotropic distillation the water contained in the polymer droplets is removed and the polymer particles then isolated by filtering off from the oil phase.
In the course of the continued technical development of superabsorbing polymers the demands made on these produds has changed markedly over the years. While during the development of the superabsorbers only the very high swelling capacHy on contad with liquid was of prime importance at first, it later turned out that not only the amount of absorbed liquid was important, but allso the firmness of the swollen gel. Retention on the one hand and gel firmness on the other are, however, opposing properties, as is known from US 3 247 171 and US Re 32,649. This means that polymers with a particularly high retention show only a low level of firmness of the swollen gel, with the result that the gel can be deformed under an applied pressure (e.g. body pressure) and further liquid absorption prevented. Therefore a balance between retention and gel strength has to be striven for so that in use fluid absorption can also take place against an applied pressure. This specific absorption characteristic is termed absorption under pressure in EP 339 461.
The method of measuring the fluid take-up under pressure (AUL) is carried out under various load;. In the course of the increased demands on superabsorbers H has turned out that the original test load of 21 g/cm2 (0.3 psi) no longer measures the desired quality standard as required for incontinence produds or for diaper designs with low fluff content and high amounts of superabsorber. Accordingly pressure loads are measured today at 42 g/cm2 (0.6 psi) and preferably at 63 g/cm2 (0.9 psi).
The increasing tendency to design sanitary articles ever smaller and thinner can only be fulfilled by reducing the voluminous fluff component in the diaper and at the same time increasing the proportion of supe,dbsoll,er. Here the superabsorber has to take over additional tasks with regard to fluid absorption and transport which were previously carried out by the fluff.
CA 02236~04 1998-0~-20 The c:haraclteristics of the superabsorbers can be improved by the process of subsequent surface cross-linkage, in particular their fluid absor,.lion under pressure, as the well-known phenomenon of "gel blocking" is suppressed, in which swollen polymer particles stick together and prevent any further absor~ tion and distribution of fluid in the diaper. During the subsequent cross-linking process the carboxyl groups of the polymer molecules are cross-linked on the surface of the super-absorber particles with cross-linking agents at a raised temperature. Among other agents, multivalent metal salts, glycidyl compounds, polyols, polyepoxides, polyamines, alkylene carbonates and polyethylene glycols are used. Subsequent cross-linking can be carried out several times. It is clear from the patent literature that the increased fluid absorption under pressure is associated with a marked reduction in retention. There is therefore a requirement for superabsorber starting products which show a less marked drop in the retention values in subsequent cross-linking. Moreover, N has not been possible so far to fix the surface cross-linkage permanently to the polymer backbone. For this reason, most of the effects obtained by surfalce cross-linking are destroyed again by mechanical actions exerted on the absorber.
For the processing of the superabsorbers various screening r~aclions are used, depending on the application, e.g. for diapers between 100 and 800,u, for cable insulation under 200~u. This means that in the case of the application in cables the fine constituents of the superabsorbers are of advantage because of their tendency to gel blocking, as this blocks off the water penetrating the cable. In the diaper this effect is not desired as n impedes the absorption and distribution of fluid, and so larger screening fractions are selected.
Besides a high degree of retention and fluid absorption under pressure supe~bsc,rl,ers have to contain low soluble constituents which arise due to incomplete cross-linking during the polymerization reaction and which are not fully retained in the body of the polymer when applied.
This finally leads to a reduction in the capacity of the superabsorber to absorb and distribute fluid in the diaper. The limiting values quoted for low soluble constituents, for example, in the US Re.
32,649 are 7.5% afler 1 hour and 17% after 16 hours. Compared to the product properties desired by present-day producers of hygiene articles, these limiting values for the soluble constituents are far too high.
The optimization of application properties of the superabsorbing polymers was carried out in the past mainly by varying the type and amount of cross-linking agent, by the pH value during polymerkation and by after-treatment of the polymer particles in the form of a coating or subsequent surface cross-linking. So far, however, H has not been possible to make available any superabsorber combining the properties of high retention, high AUL (63 g/cm2, 0.9 psi) and low soluble contents and at the same time high permeabiliiy in the gel layer for watery liquids under pressure load, high rate of absorption and lasting surface cross-linkage.
The basis of WO 94/09043 is the problem of developing new superabsorbing polymers with increased absorption capacity for watery liquids, even under pressure. It describes the solution to this problem as double cross-linked superabsorbers whose first stage of production is cross-linking during polymerization with methylene bisacrylamide, bis(acryla"~.do)acetic acid, allyl acrylate, allyl methacrylate, esters or amides with terminal vinyl and allyl functions or highly ethoxylated trimethylol propane triacrylate and as a second stage the coating of the resuHing polylmer particles on the surface with a cross-linking agent, fe"~wcd by cross-linking. In this process, which is not new, the preferred surface cross-linking agents are polyhydroxy compounds which are applied together with water or water/solvent mixtures and caused to react at raised temperatures (175 - 230~C) after the moisture in the polymer gel of the first stage has been at least partly removed.
By ihe combination of one of the above-mentioned primary cross-linking agents with the secondary surface cross-linking agenis unique product properties are said to be obtained with regalrd to retention and fluid absorption under pressure, making it possible for them to be used in hygiene articles in which the absorbing polymers have to take up considerable amounts of tluid and retain them even under pressure. When the resuHs of the trials are examined it is noticeable that the polymers show a marked improvement in their properties simply by being stored at a high CA 02236~04 1998-0~-20 temperature without the addition of a subsequent cross-linking agent. Subsequent cross-linking produces a further increase in fluid absorption under pressure at 42 g/cm2 (0.6 psi). These AUL
values are then in a range between 10 and 26 9/9, depending on the type, whereby the products with the highest AUL values only reach absorption values of 30 g/g. Absorption values of over 30 g/g are, as example 3B (absor~,lion 35 g/g and AUL 16.5 g/g) shows, only possible at the expense of the AUL at 42 g/cm2 (0.6 psi). This makes it clear that the products with the special cross-linking combination contained in WO 94/09043 in no way meets the high demands made today on such cross-linked polymers, i.e. the peak values measured therein for 42 g/cm2 (0.6 psi) are required today for a higher load at 63 g/cm2 (0.9 psi), combined with absorption values of markedly greater than 30 g/g.
WO 93/21237 describes superabsorbent polymers which are cross-linked with unsaturated esters of polyalkyl glycols and which, through a subsequent heating process, achieve an improvement in prope'rties with regard to retention and liquid absorption under a low pressure of 21 g/cm2 (0.3 psi) of up to 25 g/g. Ethoxylated t,imetl,~lol propane triacrylate is the preferred cross-linking agent, whereby the number of EO units per polyglycol chain can be betwe~en 2 and 7. According to this paper the use of non- or only slightly ethoxylated trimethylol propane triacrylate leads to considerably worse properties of the superabsorber which is cross-linked with it. Analagous to the polymers in WO 94/09043 the products described here also do not fulfil the demands placed today on absorption under a higher pressure at 63 g/cm2 (0.9 psi). In diagram 13 on page 8/8 of WO '33/21237, which shows the process of fluid absorl,lion under pressure for various pressure loads, the weakness of the polymers described there can be seen quite clearly, whose measured values of approximately 18 g/g in the interesting pressure load range of 63 g/cm2 (0.9 psi) are totally uns~ .facory. This all the more so when the measured values were obtained on a very unusual screening rractiOn of 300 - 600,um which per se results in higher measured values than the screening fraction of 150 - 8001Jm usual in the field.
US Re. 32,649 deals with the production of non-grafted superabsorbent polymers with a high gel volume, high gel strength, measured via the shear modulus and low solwble contents. The gel volume should be at least 20 9/9 and the maximum value of the soluble components, measured afler 1 hour, should not exceed 7.5% and in the state of equilibrium after 16 hours be no more than 17%. Preferably the polymers should be polymerked in a low watery starting concentration of 8 lo 24 % by weight from acrylic acid which is not neutralked, cross-linkage preferably takes place with N,N'-methylene bisacrylamide, trimethylol propane triacrylate or triallylamine. This is followed by crushing, neutralization, grinding and drying.
The production process described in Re 32,649 contains important drawbacks in the method. On the one hand the low starting concenlr~lion and the subsequent heating of the polymer gel over several hours means that the space-time yield is low, and on the other hand the step of subsequent neutralization of the solid polymer gel is technically very time-consuming and cannot be c arried out to the same quality as neutralkation in the preceding solution can be. Polymer gels neutralized subsequently are, as a rule, not neutralked consistently and often di~co'cred due to the irregular distribution of alkali. As a consequence of the uneven neutralization strong fluctuations in the quality of the product can arise.
EP 1390 077 describes superabsorbers having an improved breaking strength by using polye!thylene glycols and derivatives, such as methoxypolyethylene glycol methacrylates used as additives or comonomers. The superabsorbers are distinguished by the fact that there are less partic:les in the range < 5 ,um in a grinding test when compared with a reference product. There are no statements with respect to the swelling properties of the superabsorbers after mechanical load. The described superabsorbers are neither produced with special pre~ross-linking agents nor with subsequent surface cross-linking agents. The indicated absorptions under a pressure of at least 17 g/g, preferably > 20 g/g (AUL) merely relate to an extremely low load of about 20 g/cmZ and - measured against the art - are not in an acceptable region. For cluite a long time, prior art superabsorbers provide higher absorptions under a higher pressure (63 g/cm2) of > 20 g/g.
On the other hand, using polyethylene glycols to dedust superabsorbers is known.
CA 02236~04 1998-0~-20 In W~ 94/22940 superabsorbent polymers with a small dust component are described which arise due to a surface coating with polyol or polyethylene glycol and which show liquid absorption under low pressure at 21 g/cm2 (0.3 psi) of ~ 20 9/9. The treatment of superabsorbers with such substances has already been described in WO 93/21237 (page 12, line 15). This version showing improved abrasion and reduced dust requires, however, an additional step in the manufacturing process.
At present there are no prior art documents concerning the manufacture of superabsorbers with the desired ~m~.ndtion of properties of high permeability for watery liquids, stable surface cross-linkage, high retention, high absorption rate, pressure-resistant hydrogel and a low soluble component.
Low soluble cG"~ponents are also a precondition for superabsorbers which have to show a practical swelling pressure over a long time. If the amount of soluble contents is over 12% the superabsorL,er can no longer, after being subjected to pressure for 16 hours, in a diaper for example, store the amount of fluid required for application technological reasons.
The permeability in the layer (i.e., in x,y-direction) of the absorbent article comprising the superabsorber particularly gains in il"po,lance when constructions are used having an ever reduc:ing fluff amount with a simultaneously increasing superabsorber amount. This additionally gains in importance if the liquid distribution has to take place under a pressure of 50 glcm2, for exarnple.
A suitable method to determine the permeability of a gel layer in x,y-direction under pressure is the method of determining the absorption under pressure through a size-reduced aperture in the bottom of a so-called MP-cylinder unit.
The AAP-cylinder unit is described in EP 640 330 on page 14 (Absorption against Pressure test).
Superabsorbent polymers which are to meet today's state of the art with respect to absorbent articl~ construction, must support the liquid transport in x,y-direction, i.e., within the gel layer, such that highest possible absorption values are achieved in the mentioned measuring method. The measured values are then ~alcu~ted against the respective absorption against pressure at the same load (20 gJcm2 or 50 glcm2) and are expressed as percentage absorption. The demands placed on diapers comprising larger amounts of superabsorber require values in the range of > 50'~b; for the surface-reduced AAP-value at least 15 9/9 must be achieved.
The object of the present invention is to provide new polymers and a process for making them.
These polymers were to be used as superabsorbers in diapers or other technical applications and were to have an improved combination of properties with regard to retention, fluid absorption under pressure at 63 g/cm2 (0.9 psi) and soluble components, and which, due to their polymer composition, were to have an efficient and lasting surface cross-linkage and, due to their permeability, permit a good liquid distribution in swollen condition even under pressure (50 g/cm2).
Moreover, the superabsorbers should possess a high suction rate and a high swelling pressure.
Surprisingly it was found that cross-linked polymers absorbing watery liquids, built-up of partially neutralized monomers having monoethylenically unsaturated acid groups and optionally further monomers copolymerkable therewith as well as optional water-soluble polymers suitable as graft basis, that are produced using a cross-linker combination of 1. CH2=CH R6-CO-(OCH R3-CH R3)zO-CH2-CH R5=CH2 Il. CH2=CHR6-R5-(oCHR3-CHR3)VoR4 Ill. R'-[o(CHR3-CHR3O)u-Co-R2]x~ and/or di- or triallylamine and/or bisacrylamide with R': multivalent C2-10-alkyl R2: linear or branched C2-1 0-alkenyl CA 02236~04 1998-0~-20 R3: H, CH3, C2H5 R4: H, linear or b;anched C1-10-alkyl, R5: CO, CH2 R8: H, CH3, x: 2-~i u: 0-~15 v: 1 ~15 z: 3-~'0 and are then subjected to surface cross-linkage have a retention of greater than 30 9/9 and a liquid absorption under pressure at 63 g/cm2 (AUL 0.9 psi) of greater than 20 9/9, and their soluble contents after 1 hour are less than 6.5% and aRer 16 hours less than 10%, and their permeability within the gel layer permHs to use at least 50%-test (Absor~,lion against Pressure with a suction surface reduced by x~/0) wHh at least 15 9/9, preferably at least 20 9/9 AAP50-AX.
Due lo the preferably at least 60% of absorption capacity under a load of 50 g/cm2 in the MP-Ax.polymer structure, which is achieved according to the present invention, an improved and lasting cross-linkage between the polymer and the surface cross-linking agent takes place. This is shou~n in the fact that the AUL (63 9/cm7, after a loading test to determine the stabilHy of the surface cross-linkage, still has values of greater than 18 9/9, and this suggest.C an extraordinarily stable surface cross-linkage and an extremely thorough reaction with the surface cross-linking agent.
The c ross-linking agents thus invented according to formula I contain a (meth)allyl function and a (meth)acrylic acid ester function as well as a hydrophilic chain situated between these two funclions consisting of at least three, but preferably five to twenty ethylene oxide units. The used of mixed ethylene oxide/propylene oxide chains, which can be produced as random or block copolymers, is possible. The solubility of the cross-linking agent in the monomer solution to be polyrnerked can be adjusted by the relationship of EO/PO units. The cross-linkers can be produced, for example, by esterification of alkoxylated allyl alcohol with (meth)acrylic acid. In the newly invented cross-linking agents there may be residues of starting co."ponents to be found due to the manufacturing process which do not, however, have a negative effect on the proplerties of the superabsorber. The cross-linking agents according to formula I or their mixtures are used in a ratio of 0-1.0% by weight or preferably 0.05-0.6% by weight, or even better 0.1-0.4~/t, by weight with regard to the whole monomers.
The newly-invented monomers to be used wdh the cross-linkers according to formula ll are preferably (meth)acrylic acid ester or (meth)allyl alcohol ether from polyalkylene glycols. A
preferred type is the polyoxyalkylene glycol chain with a terminal alkyl residue. The C number in ~ the alkyl residue is in the range 1-10, preferably in the range 1-7, more preferably in the range 1-4. V\lhen choosing the alkyl group attention should be paid to the sulra~dnl character of the monomer and, if necessary, the alkyl residue has to be adjusted accor.li.lgly in order to avoid the formation of foam which can have a disruptive effect in some polymerkation processes. The polyoxyalkylene glycol chain is preferably composed of ethylene oxide andlor propylene oxide, whereby the solubility of the cross-linker in the watery monomer solution can be adjusted by the ratio of EO/P0. The content of alkyl glycol units in the chain is in the range 1-45, preferably in the range 1-30, and at best in the range 5-25. The monomers according to formula ll or their mixtures are used at up to 0.1-10% by weight, preferably at 0.5-5% by weight, or more preferably at 1.0-3.5~~, by weight with regard to the whole monomers. The monomers mentioned in ll are commercially available, e.g. the methyl polyethylene glycol methacrylates from the firm Interorgana under the name Bisomer MPEG(x)MA (x=350,1000, 2000).
According to this invention the cross-linking agents to be used accordi"g to formula lll are esters from polyhydroxy compounds with unsaturated carboxylic acids, a preferred form of which are alkoxylated. It is preferred to use C3-6-polyhydroxy compounds wHh 24 hydro~yl groups as starting compounds for the synthesis of such cross-linkers such as l,imell,ylol propane, glycerine, pentaerythritol, 1,3-propandiol, propylene glycol or 1,4 butandiol. If before esterification alkoxylation of the alcohol occurs, it is preferable to use ethylene oxide. It is preferable to use CA 02236~04 1998-0~-20 alkoxylated polyhydroxy compounds from u=1, preferably from u=3. It is preferable to use (meth)acrylic acid as the acidic ~",ponent. In a further preferred form of the cross-linking agent lll polyethylene glycol di(meth)acrylate is used. In a particularly preferred form of cross-linking agent lll di- or triallylamine and/or N,N-methylenebisacrylamide and/or bisacrylamido acetic acid are used. Also, mixtures of the last-mentioned cross-linking agents with the previously mentioned carboxylic acid esters of the polyhydroxy compounds exhibit an excellent activity.The cross-linkers in formula lll or their mixtures are used at 0.01-1.0 % by weight, preferably at 0.05 - 0.6 %
by weight, more preferably 0.05 - 0.3 % by weight with regard to the monomers. According to this invention the cross-linkers according to lll are partly available commercially, e.g. trimethylol propalne oxethylate triacrylate from the firm Cray Valley under the name Sartomer SR 415 (20 EO), Craynor 435 (15 EO), Sartomer RO 208 (9 EO), Sartomer 454 (3 EO), and pentaerythritol oxethylate tetraacrylate under the name Craynor SR 494 (5 EO) and Servocure RTT 192 (5 EO) from the firm Servo Delden BV, glycerine ethoxylate triacrylate (5,5 EO3 under the name Sartomer 921 anci glycerine propoxylate triacrylate under the name Sartomer 9021 from the firm Cray Valley, as well as polyethylene glycol-400-diacrylate as Craynor SR 344 and polyethylene glycol~00-dimethacrylate as Craynor SR 252 from the firm Cray Valley.
Surprisingly it turned out that with the new cross-linker/monomer combination mutual solubilkation of the cross-linker components, both soluble and insoluble in the watery monomer solution, is poss;~le. This also makes the use of cross-linking agents possible which cannot norm,~lly be used, or only in extremely limited amounts, due to their poor solubility.
In a further favored method the use of mixtures of highly and slightly alkoxylated cross-linkers/monomers according to 1, ll and lll in the cross-linking of the new superabsorbers has proved its worth.
The newly invented polymer for absorbing watery liquids is obtained by polymerization of ethylenically unsaturated monomers bearing acid groups, for example from acrylic acid, meth,acrylic acid, vinyl acetic acid, maleic acid, 2-acrylamido-2-methyl propane sulfonic acid, vinyl sulfonic acid, (methyl)allyl sulfonic acid or their mixtures in the presence of the cross-linkerlmonomer cc"~ lion of the components 1, ll and lll. The ratio of these acidic monomers in the monomer mixture is 55 - 99 % by weight.
The acidic monomers are at least 25 % mole, preferably 50 % mole, more preferably 50 to 80%
mole neutralized and are present, for example, as sodium, potassium or arr,r,lonium salt or their mixtures. Neutralization is carried out either by the addition of the corresponding alkali or amm~nium hydroxides or with the corresponding carbonates or hydrogen carbonates.
Optionally, the newly invented polymers can contain further comonoi"ers in order to modify their properties. Such co,-lononlers can be, for example, (meth)acrylamide, (meth)acryl nitrile, vinyl pyrrolidone, vinyl acetamide, hydroxy ethyl acrylate, alkyl aminoalkyl (meth)acrylates, alkyl amino-propyl acryla,l,i~es, acryl amidopropyl trimethyl ammonium chloride or their mixtures. Such comonomers should not exceed a proportion of 40 % by weight as they may negatively affect the swelling capacity of the superabsorber.
The newly invented polymers may contain water-soluble polymers as a grafl basis in quant-~ies of up to 30 % by weight. These include, among others, partly or fully saponified polyvinyl alcohols, starch or starch derivatives, cellulose or cellulose derivatives, polyacrylic acids, polyglycols or their mixtures. The molecular weights of the polymers added as a graft basis have to be adapted to the polymerization conditions. It may be necessary, for example in the case of a watery solution polymerization, for reasons of the viscosity of the polymer solution, to use only low or medium molecular polymers, whereas in suspension polymerization this factor plays a minor role.
Besides polymers which are obtained by cross-linking polymerization of partly-neutralized acrylic acid, it is preferable to use those containing additional proportions of graft polymerked starch or polyvinyl alcohol.
CA 02236~04 1998-0~-20 The production of the newiy invented superabsorber takes place principally according to two methods:
According to the first method the partly neutralized acrylic acid in a watery solution in the prese'nce of the cross-linker/monomer combination of 1, ll and lll as well as any necess~ry polymer additives is transforrned into a gel by radical polymerization which is then reduced in size, dried, ground, re-cross-linked and sieved down to the desired particle ske. The solution polymerkation can be carried out continuously or discontinuously. The patent literature contains a broacl spectrum of possible variations wdh regard to the concenl,dlion ratios, temperatures, type and quantity of the initiators as well as a multitude of re-cross-linking possibilities. Typical processes are described in the fo" ~ 9 patent specilicalions, which are herewith intended to become a part of the newly invented manufacturing process: US 4 076 663, US 4 286 082, DE 27 06 135, DE 35 03 458, DE 40 20 780, DE 42 44 548, DE 43 23 001, DE 43 33 056, DE 44 18 818.
The second method includes the inverse suspension and emulsion polymerization process. In these processes a watery, partly neutralked acrylic acid solution is dispersed with the help of protective ~"cids and/or emulsifiers in a hydrophobic, organic solvent and polymerization started by radical initiators. The cross-linking agents are either dissolvcd in the monomer solution and are doseld with this together or separately, and if necessary added subsequently. The addition of any polyrner grafl bases which may be present is carried out via the monomer solution or by direct additon into the oil phase. Afler the end of the polymerization the water is removed azeotropically from the reaction mixture and the polymer product filtered off. Surface cross-linkage of the polyrner particles can be carried out in the suspension as well as subsequently on the isolated polyrlner powder. The principle of the procedure is described, for example, in patent specifications US 43 40 706, DE 37 13 601, DE 28 40 010 and should be considered as part of the newly invented manufacturing process.
The addition of the subsequent cross-linking agent is oflen carried out to advantage in the form of a solution in water, organic solvents or their mixtures, in particular when small quantities of re-cross-linking agent are used. Suitable mixing machines for the application of the re-cross-linking agent are, for example, Patterson-Kelly mixer, DRAIS eddy mixer, Lodige mixer, Ruberg mixer, screw mixer, pan mixer and fluidked bed mixer as well as continuously working vertical mixers in which the powder is mixed at a high frequency by means of rotating knives (Schugi mixer). Afler the re-cross-linking agent has been mixed with the pre-cross-linked polymer heating is carried out up to temperatures of 120 to 250~C, preferably up to 135 to 200~C, more preferably up to 150 to 185~lv in order to carry out the re-cross-linking reaction. The length of the subsequent heating is limited by the point at which the desired set of properties of the superabsorber is destroyed again as a result of heat damage.
The newly invented superabsorbers show an unprecedented combination of favorable properties.
Due to the positive influence of the cross-linker/comonomer combination the high retention of the polyrner present before re-cross-linking is stabilized to such an extent that after the surface re-cross-linking a retention of over 30 g/g is still measured.
Afler the absorption of fluid, whose rate is less than 40 seconds, preferably less than 35 seconds, more preferably less than 30 seconds, the swollen gel particles stand out due to their dry handle, i.e. tlhey do not possess the undesired wet, sticky surface which arises with insufficient cross-linking/re-cross-linking. In addition, together with the high retention the soluble contents afler 1 hour are less than 6.5 %, preferably less than 5 % or afler 16 hours less than 10 %, preferably less than 8 %. The liquid absorption under a pressure (AUL) of 63 g/cm2 (0.9 psi) is greater than 20 9/'9, preferably greater than 23 g/g, more preferably greater than 25 g/g.
Due to the cross-linker/monomer combination according to the present invention the superabsorbers obtain an excellent permeability for liquids in swollen condition under load. The cross-linker/monomer combination according to the present invention provides an efficient and lasting surface cross-linkage of the polymer. This makes it possible to produce superabsorbers CA 02236~04 1998-0~-20 whichl, after a loading test to examine the stability of surface cross-linkage (SDOV = "St~ at der Oberl1achen_ernekungn), still have AUL values (63 g/cm2) of at least 18 9/9, preferably of greater than ,20 g/g, and most preferably of greater than 22 9/9.
The swelling pressure of the newly-invented polymers is high and after 20 minutes is at least 600 g, preferably at least 800 9, more preferably greater than 900 9.
The newly-invented hydrophilic superabsorbers are used everywhere where watery liquids have to be absorbed. This includes, for example, the generally known ~FFI ~ions for superabsorbers in hygiene articles in the form of diapers for small children and incontinence products for adults, in ladies' napkins, in plasters, in food packagings, in the field of agriculture for plant raising, in cable insulation, in absorbent layers made of paper, water-soluble polymers and thel"~opla~lic man-made materials and foams as well as car,ier~ for active subslances with the task of delayed release to the environment.
In the following examples the manufacture and properties of the newly-invented polymers are explalined and in the chapter on testing methods the regulations governing the determination of the properties of superabsorbers are described.
Test Methods 1. R~!tention The retention is measured according to the method described in EP 514 724 (page 4, lines 6-22).
2. FllJid AbsorPtion under Pressure (AUL~
The lluid absorption under pressure (AUL) is determined according to the method described in EP
514 724 (page 4, lines 23-28). AUL 63 is measured at a pressure of 63 g/cm2 (0.9 psi), A~)L 21 (0.3 psi) at 21 g/cmZ.
The lluid absorption under pressure (AUL) is determined according to the method described in EP
514 724 (page 4, lines 23-28). AUL 63 is measured at a pressure of 63 g/cm2 (0.9 psi), A~)L 21 (0.3 psi) at 21 g/cmZ.
3. Soluble Contents (LA) The soluble contents (1 hour and 16 hours) are determined as described in US 4 654 039, with ~ the exception that a 0.9 % sodium chloride solution is used as test fluid instead of synthetic urine.
4. R~!sid~lal Monomers (RM) The residual monomers (RM) are determined from the filtrate from the determination of the soluble components by means of the HPLC method, and evaluated according to the method of the internal standard.
5. S~ ellin~ Pressure (SP) The swelling pressure is determined in a Stevens LFRA Texture Analyser (setting: speed: 1.0 mrr~sec; distance 00, hold position). To this purpose 0.500 g of the powder is weighed into a measuring cylinder of 7.4 cm height and 2.7 cm diameter (grain fraction 300 - 600 mm), to which 10 ml of 0.9 % sodium chloride solution is added. Then the measuring cylinder (height 3 5 cm, diameter 2.5 cm) is placed into the cylinder until the clislance of the level of the lower edge of the cylindrical measuring body amounts to 12 mm from the surface of the sample in the measuring cylinder. Owing to the gel expansion the measuring cylinder is pushed upwards against a two-CA 02236~04 1998-0~-20 way lorce-measuring cell and is indicated at the device in grams. The swelling pressure SP is measured after different periods of time.
6. Absorption aaainst Pressure with reduced s~l~tio.~ surface (AAP-AX2 This lest determines a superabsorber's capability of sucking liquid out of a liquid reservoir under a defined pressure. This is carried out by means of a cylinder unit having a reduced suction surface. In contrast to the usual method of determining the Absorption against Pressure, the liquid transport in xy-direction (permeability) in the gel layer is also observed.
The measuring apparatus described in EP 640 330, page 14, is used as cylinder unit for measuring. This apparatus is modified such that part of the sieve bottom is covered with a layer which is impermeable to liquids. In the middle of the sieve bottom, centrally arranged, there is left a circular aperture through which liquid absorption takes place.
The remaining suction surface may amount, for example, to 9, 14, 17, 25, 34, or 60% of the origirlal surface of 28.27 cm2.
The percentage suction surface, relative to the usual MP-surface of 28.27 cm2, is indicated as index Ax:
-MP-Ag (suction surface 0 18 mm) -MP-A14 (suction surface 0 23 mm) -MP-A17 (suction surface 0 25 mm) -MP-A2s (suction surface 0 30 mm) -AAP-A34 (suction surface 0 35 mm) -MP-A60 (suction surface 0 46.5 mm) 0.900 i 0.005 9 of the superabsorber is weighed in and sprinkled as uniformly as possible onto the sieve fabric of the plastic cylinder (0 = 6 cm, height = 5 cm, sieve fabric: 400 mesh = 37 ~m) located in the bottom, and is then loaded with a defined weight. The load optionally amounts to 20 glcm2 or 50 g/cm2.
The ,cylinder unit (Plexiglass-cylinder with sieve fabric of reduced surface, SAP, covering plate, and weight) is weighed and placed on a filter plate (0 = 12 cm, porosity = 0, e.g. Schott ceramic filter Duran) which is impregnated with liquid and covered with filter paper (Schleicher und Schull, Sch~/arzband 589, 0 = 11 cm). The filter plate lies in the liquid up to its upper edge. In general, 0.9~~c NaCI-solution is used, other test solutions, such as synthetic urine, may also be used.
Supernatant liquid is to be avoided.
The SAP is allowed to suck for a defined period. In general, the residence time amounts to 60 minutes; optionally other periods are possible. The Absorption against Pressure with reduced suction surface (AAP-A~ can be determined by re-weighing the cylinder unit. At least one double determination is to be carried out each time. In order to calculate the pe,.;entage capac;ty, the MP-value with the corresponding load is also determined.
Ca~c~ tion of the surface-reduced AAP-A~value is effected accordi"g to the f~ J;.I9 fomula:
B - A
{AAP - A,d = [9/9]
E
{AAP - A,d * 100 Capacity = [%]
AAP
{MP-A,d : Absorption against Pressure with reduced suction surface [g/g]
A : Weight of the cylinder unit prior to sucking [g]
B : Weight of the cylinder unit after sucking [g E : Initial weight of superabsorber [g]
CA 02236~04 1998-0~-20 7. Stalbilit~ test of surface cross-linka~e (SDOV) A cylindrical hollow body made of corundum with an internal diameter and an intemal length of app,oAimdtely 8 cm is filled with 20 g of superabsorber powder and approximately 130 9 of cylindrical corundum particles which have a dia",eter and length of 1.27 cm each, and then rotate!d at a rate of 150 r.p.m. After 10 minutes the stability test is terminated and the abso"~tion under pressure determined (AUL 63).
The measuring apparatus described in EP 640 330, page 14, is used as cylinder unit for measuring. This apparatus is modified such that part of the sieve bottom is covered with a layer which is impermeable to liquids. In the middle of the sieve bottom, centrally arranged, there is left a circular aperture through which liquid absorption takes place.
The remaining suction surface may amount, for example, to 9, 14, 17, 25, 34, or 60% of the origirlal surface of 28.27 cm2.
The percentage suction surface, relative to the usual MP-surface of 28.27 cm2, is indicated as index Ax:
-MP-Ag (suction surface 0 18 mm) -MP-A14 (suction surface 0 23 mm) -MP-A17 (suction surface 0 25 mm) -MP-A2s (suction surface 0 30 mm) -AAP-A34 (suction surface 0 35 mm) -MP-A60 (suction surface 0 46.5 mm) 0.900 i 0.005 9 of the superabsorber is weighed in and sprinkled as uniformly as possible onto the sieve fabric of the plastic cylinder (0 = 6 cm, height = 5 cm, sieve fabric: 400 mesh = 37 ~m) located in the bottom, and is then loaded with a defined weight. The load optionally amounts to 20 glcm2 or 50 g/cm2.
The ,cylinder unit (Plexiglass-cylinder with sieve fabric of reduced surface, SAP, covering plate, and weight) is weighed and placed on a filter plate (0 = 12 cm, porosity = 0, e.g. Schott ceramic filter Duran) which is impregnated with liquid and covered with filter paper (Schleicher und Schull, Sch~/arzband 589, 0 = 11 cm). The filter plate lies in the liquid up to its upper edge. In general, 0.9~~c NaCI-solution is used, other test solutions, such as synthetic urine, may also be used.
Supernatant liquid is to be avoided.
The SAP is allowed to suck for a defined period. In general, the residence time amounts to 60 minutes; optionally other periods are possible. The Absorption against Pressure with reduced suction surface (AAP-A~ can be determined by re-weighing the cylinder unit. At least one double determination is to be carried out each time. In order to calculate the pe,.;entage capac;ty, the MP-value with the corresponding load is also determined.
Ca~c~ tion of the surface-reduced AAP-A~value is effected accordi"g to the f~ J;.I9 fomula:
B - A
{AAP - A,d = [9/9]
E
{AAP - A,d * 100 Capacity = [%]
AAP
{MP-A,d : Absorption against Pressure with reduced suction surface [g/g]
A : Weight of the cylinder unit prior to sucking [g]
B : Weight of the cylinder unit after sucking [g E : Initial weight of superabsorber [g]
CA 02236~04 1998-0~-20 7. Stalbilit~ test of surface cross-linka~e (SDOV) A cylindrical hollow body made of corundum with an internal diameter and an intemal length of app,oAimdtely 8 cm is filled with 20 g of superabsorber powder and approximately 130 9 of cylindrical corundum particles which have a dia",eter and length of 1.27 cm each, and then rotate!d at a rate of 150 r.p.m. After 10 minutes the stability test is terminated and the abso"~tion under pressure determined (AUL 63).
8. Rate of Liquid AbsGr"tion (SG) In this test the time is measured in which 1 9 of superabsorber absorbs 20 9 of a 0.9 % sodium chloride solution at room temperature. The method of this test is described in EP 443 627, page 12, "F ree Swell Rate".
Exa~ples Coml~arative Example 1 a) 400 kg/h of a 33 % monomer solution made of acrylic acid, partly neutralked with sodium hydrc,xide solution at 70 % mole, 3.5 % by weight (relative to the acrylic acid) methoxy polyethylene glycol (22EO) methacrylate, 0.35 % by weight (relative to the acrylic acid), trimel hylol propane triacrylate, and 0.4 % by weight sodium carbonate (relative to the acrylic acid) is rinsed continuously with nitrogen and mixed at 4-5~C with the f~"~w;ng catalyst solutions: 100 ppm hydrogen peroxide, 150 ppm sodium peroxide sulfate and 100 ppm azoisobutyroamidine dihydrochloride. For continuous polymerkation on an endless loop 15 ppm of ascorbic acid is added. After 40 minutes polymerkation time the gel produced is reduced to small pieces and dried on a belt drier at an air temperature of 160~C.
After grinding and sieving off to 150 - 850 I~m the polymer is put into te"~por~ry storage.
Properties of the starting product:
Retention: 39.5 9l9 Soluble contents after 1 hour: 9.3 %
Soluble contents after 16 hours: 14.1 %
b) Re-cross-linking of the starting product:
The powdery polymer obtained after comparison 1 a) is sprayed continuously at a rate of 80 kg/h in a paddle mixer (2000 r.p.m.) with 1.5% of a solution of 1 part of ethylene carbonate and 2 parts of walter and warmed in a paddle drier equipped w'~th heated mixed elements.
Steaming temperature: 190 ~C
Heating area: 1.6 mZ
average holdingtime 20 min.
After the product has cooled protective sieving is carried out at 850 ~ m.
Propl~rties of the re-cross-linked product:
Retention: 33.5 919 AUL(21 g/cm2): 31 919 AUL (63 g/cm2): 18 9/9 CA 02236~04 1998-0~-20 Solublecomponentsafler 1 hour: 6.4 %
Soluble cG"lponents afler 16 hours: 11.0 %
SG: 33 s AUL (63 glcm23 n. SDOV: 12 9/9 QD (20'): 496 9 Coml~arative Example 2 a) As in comparison 1 a) 400 kglh of a 33% monomer solution made of acrylic acid partly neutralized with sodium hydroxide solution at 70% mole and 0.3 % by weight 15 EO trimethylol propalne triacrylate is continuously initiated, polymerized and worked up to a powdery resin.
Retention: 42 9/9 Soluble contents afler 1 hour: 12.0 %
Soluble contents afler 16 hours: 19.5 %
b) Re-cross-linking The powdery polymer produced according to co,~lparison 2a) is treated as in comparison 1b).
The resulting product properties are as follows:
Retention: 31 9/9 AUL(21 g/cm2): 30 9/9 AUL (63 9/Cmv 17 9/9 Soluble contents afler 1 hour: 6.5 %
Soluble contents afler 16 hours: 20.5 %
SG: 62 s AUL (63 glcmZ) according to SDOV: 12 9/9 QD (20'): 528 9 Example 1 a)As in cor"palrison example 1a) a 70% mole partly neutralked acrylic acid solution which contalins - relative to acrylic acid - 3.5 % methoxy polyethylene glycol (22EO) methacrylate, 0.2 %
trimethylol propane triacrylate, 0.3 % polyethylene glycol (10 EO) monoallyl ether acrylate is polymerized and worked up to a powdery resin with the fe'l~ g properties:
Retention: 41 9/9 Soluble contents afler 1 hour: 6.1 %
Soluble contents afler 16 hours: 9.5 %
b) Re-cross-linking The powdery polymer produced according to example 1a) is afler-treated as in comparison example 1 b) and has the following properties:
Retention: 34 9/9 AUL (21 glcm2): 34 glg AUL (63 glcm2): 25.5 g/g Soluble co",ponents afler 1 hour: 4.8 %
Soluble co,nponents afler 16 hours: 9.4 %
SG: 30 s CA 02236~04 1998-0~-20 AUL (63 g/cm2) according to SDOV: 19 g/g QD (20'): 810 9 Examlple 2 a) As in comparison example 1a) 400 kg/h of an acrylic acid solution partly neutralized to 70 %
mole which - relative to acrylic acid - contains 3.5 % ~ lhoxy polyethylene glycol (22EO) "~etl,clcrylate, 0.2 % llill.ell)ylol propane triacrylate and 0.4 % polyethylene glycol (10 EO3 monoallyl ether acrylate is polymerked, dried, ground and sieved off to a particle ske fraction of 150 - 850,um.
Retention: 38.5 9l9 Soluble components after 1 hour: 5.8 %
Soluble components after 16 hours: 7.6 %
b) Re-cross-linking:
The polymer produced accordil-g to example 2 is coated as in cG"",~a,ison example 1b) and treated thermically. lt has the f~ ;.,g ch~rdcteristic data:
Retention: 32 9/9 AUL (21 g/cm2): 33.5 9l9 AUL (63 g/cm2): 25.5 9l9 Soluble contents after 1 hour:4.8 %
Soluble contents aftre 16 hours:7.0 %
SG: 33 s AUL (63 9/cm7 according to SDOV:20 9/9 QD (20'): 960 9 Example 3 (W 75067) a) As in comparison example 1a) 400 kg/h of an acrylic acid solution partly neutralked to 70 %
mole containing - relative to acrylic acid - 3.5 % methoxy polyethylene glycol (22EO) methacrylate, 0.3 % 3-EO-tlilne~ lol propane triacrylate and 0.4 % polyethylene glycol (10EO) monoallyl ether acrylate is polymerized by the addNion of the initiators mentioned in comparison example 1a). The gel produced is reduced in size, dried, ground and sieved down to 150 - 850 ~ ~m. l he f~ ,;ng properties were found in the starting product:
Retention: 36 g/g Soluble components after 1 hour: 5.0 %
Soluble components after 16 hours: 6.6 %
b) R e-cross-linking As in co")parison example 1 b) 80 kg/h of polymer from example 3a) is mixed with 1.5 % ethylene carbonate solution and then warmed in the paddle drier. The polymer produced shows the following characteristic data:
Retention: 32 9l9 AUL(21 g/cm2): 34 9/9 AUL(639/cmV: 24 9lg Soluble contents after 1 hour: 2.7 %
Soluble contents after 16 hours:6.8 %
SG: 28s AUL (63 g/cm7 according to SDOV: 18 9/9 CA 02236~04 1998-0~-20 In Examples 4 - 20 and Comparaffve Examples 3-8 polymerkation and re-cross-linking are carried out accGr.li,.g to the f~ ng recommended recipe:
In a cylindrical plastic vessel a polymerisation preparation of altogether 1000 9 is made up. To this purpose 280 9 acrylic acid as well as the cross-linking agent, con~onG",ers and further cGmFIonents to be used are prepared in cGr"r'etely softened water. Whilst being stirred and allowed to cool this is then partly neutralked with 50 % sodium h~droxide solution to a degree of neutralization of 70 %. The solution is cooled down to 7-8~C and nitrogen bubbled through until the oxygen content of the ",onGmer solution has dropped to a level below 0.2 ppm. Then 100 ppm of azo-bis(2-amidinol)ropane) dihydr~,chla i-le dissolved in 10 9 VE water, 300 ppm sodium persulfate, dissolved in 6 9 VE water and 70 ppm hydrogen peroxide (35%) dissolved in 1 9 VE
water are added. Then polymerkation is started by the addition of 9 ppm ascorbic acid in 2 g water, resuHing in a marked rise in temperature. After the end of the polymerkation the gel-like polyrner block is reduced in ske, ground and dried. The polymer is then ground and sieved down to the grain f,a-1ion 150-800,u.
Re-cross-linking:
100 9 of the sieved polymer is mixed thorou~hly with a solution of 0.5 9 ethylene carbonate, 2 9 VE water and 4 9 acetone and then heatè~to a temperature of 180~C in an oven.
The composition of the superabsorbers with regard to the cross-linkers, comonomers and further components as well as the properties of the product are listed in tables 1 to 3.
It can be seen from the table that the newly-invented polymers have a cG~ iLl~lion of good properties:
Retention > 30 9/9 Abscrption under pressure (49 g/cm2) ~ 20 9/9 Absorption under pressure (63 g/cm2) after SDOV ~ 18 9/9 Rate of liquid up-take < 40 s Soluble contents (16 h) < 10 %
Swelling pressure (20 min) ~ 800 9 In the cG",pa,~ e examples it can be seen that by varying the amount of cross-linker it is possible to attain individual measured values but not the entire con,~.,dlion of the good properties.
CA 02236~04 1998-0~-20 Example 21 - 24 As in Example 1 further experiments were carried out with the following cross-linker/monomer combinations, the quantities relate to %-wt. acrylic acid:
Cross-linkerlCo- Example 21 (Code Example 22 (Code Example 23~ (Code Example 24 (Code r D 1omer W 75066) W 75069) W 76164) W 76165) ''-A-15EO 0.4 '--A-3EO o 3 PE- ~o-r~ 0.14 M-~ EO-A 0.2 ~ ~.2 0.4 0.4 T /IP''A .' I\ PEI31000MA 3.5 ;~. ~ 2.9 1.67 Product properties (re-clross- inked) R~-er t on 'g/g] 6~.5 3~,.5 3A ~ .5 A J ~ [9~9] ' ~-5 2 26.5 AJ I 8acc. ~ 20 1 '~
SDO'~ lg/g]
MP _ 1 A?~4 l9/9] 6.5 1- "3.5 AAP . ) A~4 [%] 3 6 2 1h ~~] 3.0 .5 2.~ .5 A 16h [ ~O] 8.2 ~.3 6.~ .5 *: Example 24 was carried out wi-hout the addHion of sodium carbonate Example 25 - 30 According to the general formulation of Examples 4 - 20 further superabsorbent polymers according to the present invention were produced using triallylamine as cross-linker component lll. In Example 27, 0.4 9 sodium carbonate were added after neutralization of the acrylic acid. The results are shown in Table 4.
Example 31 According to the general formulation of Example 1 a test was carried out with a cross-linker/monomer combination of 2.5%-wt. methoxypolyethylene glycol(22EO)-methaclylate, 0.35C~o-wt. polyethylene glycol(10EO)-monoallyl ether-acrylate, and 0.12%-wt. triallylamine. The starting product had a retention of 38 9/9, the re-cross-linked product had a retention of 32.5 g/g, an AIJL (63 g/cm2) of 26.5 9/9, an AUL according to SDOV of 20 9/9, a swelling pressure of 1340 g (afler 20'), and 1080 9 (after 2h), and 6.4% soluble contents (after 16h).
Comparative Example 9 and Examples 32 - 34 These examples show the improved permeability in the swollen gel layer by using methoxypolyethylene glycol methacrylate as comonomer. The results are summarked in Table 5.
Exan1ple 32 According to the general formulation of Example 1 a test was carried out using a cross-linkellmonomer combination of 1 %-wt. methoxypolyethylene glycol(17EO)-methacrylate, 0.3%-wt.
CA 02236~04 1998-0~-20 polye!thylene glycol(10EO)-",onoal:yl ether acrylate and 0.1 %-wt. 3-EO-trimethylolpropane triacrylate. The starting product had a retention of 37.5 gtg the re-cross-linked product had a retention of 32.5 g/g an AUL (63 g/cmV of 23.5 g/g and 8.5% soluble contents (after 16h).
Exannple 33 According to the general formulation of Example 1 a test was carried out using a cross-linkellmonomer combination of 2%-wt. methoxypolyethylene glycol(17EO)-methacrylate 0.3%-wt.
polyethylene glycol(10EO)-monoallyl ether acrylate and 0.1 %-wt. 3-EO-l,i"~eti"rlolpropane triacrylate. The starting product had a retention of 37.5 9/9 the re-cross-linked product had a retention of 31.5 9/9 an AUL (63 g/cm2) of 24.5 9/9 and 8.5% soluble contents (after 16h).
Exannple 34 According to the general formulation of Example 1 a test was carried out using a cross-linke,/mono",er combination of 3%-wt. mell,oxypolyethylene glycol(17EO)-methacrylate 0.3%-wt.
polyethylene glycol(10EO)-monoallyl ether acrylate and 0.1 %-wt. 3-EO-lri",ell"~lolpropane triacrylate. The s~,li"g product had a retention of 39 g/g the re-cross-linked product had a retention of 32 g/g an AUL (63 g/cmV of 23.5 9/9 and 6.5% soluble contents (after 1 6h).
Comparative ExamPle 9 According to the general formulation of Example 1 a test was carried out using a cross-Iinker/monomer cGn,t nation without methoxypolyethylene glycol(17EO)-methacrylate and consisting of 0.3%-wt. polyethylene glycol(10EO)-monoallyl ether acrylate and 0.1 %-wt. 3-EO-trimethylolpropane triacrylate. The starting product had a retention of 33 9/9 the re-cross-linked product had a retention of 32 9/9 an AUL (63 g/cm2) of 19.5 9/9 and 7.6% soluble contents (after 16h) Comparative Examples 10 -12 The MP50-A34 value is determined in commercially available superabsorbers. The measured values prove that the products do not reach the limiting values demanded according to the present invention (Table 6).
tD C~l ~ I' OO C~ N
~ _ S~ ~
,_ _ ~0 0 0 ~ ~ o ~
~r a~ cn ~ ~ ~; G u') ~ ~ ~ ~ C
,C _ l~ O ~I C~l C~î C"l O
c~ N 1-~
o ~ ~ ~ ~ C~ î ~~) t~ O
a~
' ~~ ~ ~ ~ ~ o ~ ~ o o a) ~ ~ o ~
a~ O ~ ~ c ~ U~ ~
o _ 2 C.~o C~ --o 3~ E _ C ~ C~ O
o O
_--o--~" o ~ o O O C~l oO E o , ~ ~O O o o o O ~ ~
$ ~ E ~ E E
. ~
a) O o o~ U~ ~ ~ ~
C a ~ ~ ~ o a) ~ ~' o~ a) o ~ ~
-o o ~ o o o c~
~ o n U~ ~
~_ .o _ ~o ~~ ~ 5 E ~ 3 c~ l o c~ o ~~ ~ E
Co ~ ~ Se ~ ~ ~ o ~~ ~ ~ ~ ~ ~ O
Q ~ ,c ~
O O O O O O C~ O o o C~ o C
~ ~ ~'I ~' E ~ ~ ~ o o ~
-- o a~ a~
~e ~ 0 0 C ~ ~ ~ ~ U~
.o ~ ~ o o o o ~ U~
~-'' Q ~ ~ ~ ~ ~ O
Q ~ ~ ~ ~ ~ 0 tD a~
a~
7 ,c ~O ~
~ CO 0 o~
C ,c 1~3 E
2 c~ ''' o o ~ o o ~
C ~ O o n 'D ~ ~ 0 ' I_ I Cl ~ C~ N ~ N C~ 3 o' .3 ~_ ~ ~ ~ '~ ~ ~ ~ C~i ~a~ ~ C
tY 3~ ~' ' ,c C ~ ~- _ ~ Q
o o c~ w O o O ~
~ ~ '_ _~ c 4- 0 E '~ ~ o ~ ~ ~t, $ ~ ~ ~ ~ ~
~~ ~ as c ~ ~, ~ -~ o ~ ~
~ ~ C~l C~l C~l C~l N ~ ~ ~
Cl_ o o O O o o ~ U~ o , ~ ' ~N
E a~
~ Q ~ ~ 0 ~ O
li3 0 ~ ~ ~ ~ C'~
o u~
_ ~ ~ U~
C~
~ 2' Qo ~~~ 2 o o~ .
Q Q ~ O
N ~
-- O
~' 3 2 ~
L 10 ~ N N C~l C"
N c~ N CD N N U~
6 0 ~
~ ~ N ~ N ~ ~ ~ ~ o C
n~ ~3 ~ O
O .0 ~ o 2 >
~~ C~ o _ ~ ~ ~ c = ~ a ~ a E o ~ N N C~l N N N c C g w S '-O ~ O
C ~ O C W ~
.~ ~ ~ ~ ~ ~. _--V ~ F ~ ~ 5 ~n ~ O O O O ~ I O O
.. ._ ' O ~
u~ ~ r~ oo 0 0 111 N N C~.l N N ~) 1-- ~ ~
o O
a~ ~
o o n ~ L~ O
o o ~ ~ ~ ~
C ~) C" 1~ ~ 0,e3 lji 0 ~ O
E ~ ~ o ~ ''1 ''' ~ ' ~
2 o ~
O -- ~ ~ a~
o o o o _ o , O ~_ o o o o ~
E E ~ "~
Table 6 Example Commcrcial Product AAP50-A34l~/~] AAP50-A34r~1 Comp. 10Salsorb CL20 8.5 63 Comp. 11ASAP2000 14 74 Comp. 12Sanwet IM7000 6.5 43
Exa~ples Coml~arative Example 1 a) 400 kg/h of a 33 % monomer solution made of acrylic acid, partly neutralked with sodium hydrc,xide solution at 70 % mole, 3.5 % by weight (relative to the acrylic acid) methoxy polyethylene glycol (22EO) methacrylate, 0.35 % by weight (relative to the acrylic acid), trimel hylol propane triacrylate, and 0.4 % by weight sodium carbonate (relative to the acrylic acid) is rinsed continuously with nitrogen and mixed at 4-5~C with the f~"~w;ng catalyst solutions: 100 ppm hydrogen peroxide, 150 ppm sodium peroxide sulfate and 100 ppm azoisobutyroamidine dihydrochloride. For continuous polymerkation on an endless loop 15 ppm of ascorbic acid is added. After 40 minutes polymerkation time the gel produced is reduced to small pieces and dried on a belt drier at an air temperature of 160~C.
After grinding and sieving off to 150 - 850 I~m the polymer is put into te"~por~ry storage.
Properties of the starting product:
Retention: 39.5 9l9 Soluble contents after 1 hour: 9.3 %
Soluble contents after 16 hours: 14.1 %
b) Re-cross-linking of the starting product:
The powdery polymer obtained after comparison 1 a) is sprayed continuously at a rate of 80 kg/h in a paddle mixer (2000 r.p.m.) with 1.5% of a solution of 1 part of ethylene carbonate and 2 parts of walter and warmed in a paddle drier equipped w'~th heated mixed elements.
Steaming temperature: 190 ~C
Heating area: 1.6 mZ
average holdingtime 20 min.
After the product has cooled protective sieving is carried out at 850 ~ m.
Propl~rties of the re-cross-linked product:
Retention: 33.5 919 AUL(21 g/cm2): 31 919 AUL (63 g/cm2): 18 9/9 CA 02236~04 1998-0~-20 Solublecomponentsafler 1 hour: 6.4 %
Soluble cG"lponents afler 16 hours: 11.0 %
SG: 33 s AUL (63 glcm23 n. SDOV: 12 9/9 QD (20'): 496 9 Coml~arative Example 2 a) As in comparison 1 a) 400 kglh of a 33% monomer solution made of acrylic acid partly neutralized with sodium hydroxide solution at 70% mole and 0.3 % by weight 15 EO trimethylol propalne triacrylate is continuously initiated, polymerized and worked up to a powdery resin.
Retention: 42 9/9 Soluble contents afler 1 hour: 12.0 %
Soluble contents afler 16 hours: 19.5 %
b) Re-cross-linking The powdery polymer produced according to co,~lparison 2a) is treated as in comparison 1b).
The resulting product properties are as follows:
Retention: 31 9/9 AUL(21 g/cm2): 30 9/9 AUL (63 9/Cmv 17 9/9 Soluble contents afler 1 hour: 6.5 %
Soluble contents afler 16 hours: 20.5 %
SG: 62 s AUL (63 glcmZ) according to SDOV: 12 9/9 QD (20'): 528 9 Example 1 a)As in cor"palrison example 1a) a 70% mole partly neutralked acrylic acid solution which contalins - relative to acrylic acid - 3.5 % methoxy polyethylene glycol (22EO) methacrylate, 0.2 %
trimethylol propane triacrylate, 0.3 % polyethylene glycol (10 EO) monoallyl ether acrylate is polymerized and worked up to a powdery resin with the fe'l~ g properties:
Retention: 41 9/9 Soluble contents afler 1 hour: 6.1 %
Soluble contents afler 16 hours: 9.5 %
b) Re-cross-linking The powdery polymer produced according to example 1a) is afler-treated as in comparison example 1 b) and has the following properties:
Retention: 34 9/9 AUL (21 glcm2): 34 glg AUL (63 glcm2): 25.5 g/g Soluble co",ponents afler 1 hour: 4.8 %
Soluble co,nponents afler 16 hours: 9.4 %
SG: 30 s CA 02236~04 1998-0~-20 AUL (63 g/cm2) according to SDOV: 19 g/g QD (20'): 810 9 Examlple 2 a) As in comparison example 1a) 400 kg/h of an acrylic acid solution partly neutralized to 70 %
mole which - relative to acrylic acid - contains 3.5 % ~ lhoxy polyethylene glycol (22EO) "~etl,clcrylate, 0.2 % llill.ell)ylol propane triacrylate and 0.4 % polyethylene glycol (10 EO3 monoallyl ether acrylate is polymerked, dried, ground and sieved off to a particle ske fraction of 150 - 850,um.
Retention: 38.5 9l9 Soluble components after 1 hour: 5.8 %
Soluble components after 16 hours: 7.6 %
b) Re-cross-linking:
The polymer produced accordil-g to example 2 is coated as in cG"",~a,ison example 1b) and treated thermically. lt has the f~ ;.,g ch~rdcteristic data:
Retention: 32 9/9 AUL (21 g/cm2): 33.5 9l9 AUL (63 g/cm2): 25.5 9l9 Soluble contents after 1 hour:4.8 %
Soluble contents aftre 16 hours:7.0 %
SG: 33 s AUL (63 9/cm7 according to SDOV:20 9/9 QD (20'): 960 9 Example 3 (W 75067) a) As in comparison example 1a) 400 kg/h of an acrylic acid solution partly neutralked to 70 %
mole containing - relative to acrylic acid - 3.5 % methoxy polyethylene glycol (22EO) methacrylate, 0.3 % 3-EO-tlilne~ lol propane triacrylate and 0.4 % polyethylene glycol (10EO) monoallyl ether acrylate is polymerized by the addNion of the initiators mentioned in comparison example 1a). The gel produced is reduced in size, dried, ground and sieved down to 150 - 850 ~ ~m. l he f~ ,;ng properties were found in the starting product:
Retention: 36 g/g Soluble components after 1 hour: 5.0 %
Soluble components after 16 hours: 6.6 %
b) R e-cross-linking As in co")parison example 1 b) 80 kg/h of polymer from example 3a) is mixed with 1.5 % ethylene carbonate solution and then warmed in the paddle drier. The polymer produced shows the following characteristic data:
Retention: 32 9l9 AUL(21 g/cm2): 34 9/9 AUL(639/cmV: 24 9lg Soluble contents after 1 hour: 2.7 %
Soluble contents after 16 hours:6.8 %
SG: 28s AUL (63 g/cm7 according to SDOV: 18 9/9 CA 02236~04 1998-0~-20 In Examples 4 - 20 and Comparaffve Examples 3-8 polymerkation and re-cross-linking are carried out accGr.li,.g to the f~ ng recommended recipe:
In a cylindrical plastic vessel a polymerisation preparation of altogether 1000 9 is made up. To this purpose 280 9 acrylic acid as well as the cross-linking agent, con~onG",ers and further cGmFIonents to be used are prepared in cGr"r'etely softened water. Whilst being stirred and allowed to cool this is then partly neutralked with 50 % sodium h~droxide solution to a degree of neutralization of 70 %. The solution is cooled down to 7-8~C and nitrogen bubbled through until the oxygen content of the ",onGmer solution has dropped to a level below 0.2 ppm. Then 100 ppm of azo-bis(2-amidinol)ropane) dihydr~,chla i-le dissolved in 10 9 VE water, 300 ppm sodium persulfate, dissolved in 6 9 VE water and 70 ppm hydrogen peroxide (35%) dissolved in 1 9 VE
water are added. Then polymerkation is started by the addition of 9 ppm ascorbic acid in 2 g water, resuHing in a marked rise in temperature. After the end of the polymerkation the gel-like polyrner block is reduced in ske, ground and dried. The polymer is then ground and sieved down to the grain f,a-1ion 150-800,u.
Re-cross-linking:
100 9 of the sieved polymer is mixed thorou~hly with a solution of 0.5 9 ethylene carbonate, 2 9 VE water and 4 9 acetone and then heatè~to a temperature of 180~C in an oven.
The composition of the superabsorbers with regard to the cross-linkers, comonomers and further components as well as the properties of the product are listed in tables 1 to 3.
It can be seen from the table that the newly-invented polymers have a cG~ iLl~lion of good properties:
Retention > 30 9/9 Abscrption under pressure (49 g/cm2) ~ 20 9/9 Absorption under pressure (63 g/cm2) after SDOV ~ 18 9/9 Rate of liquid up-take < 40 s Soluble contents (16 h) < 10 %
Swelling pressure (20 min) ~ 800 9 In the cG",pa,~ e examples it can be seen that by varying the amount of cross-linker it is possible to attain individual measured values but not the entire con,~.,dlion of the good properties.
CA 02236~04 1998-0~-20 Example 21 - 24 As in Example 1 further experiments were carried out with the following cross-linker/monomer combinations, the quantities relate to %-wt. acrylic acid:
Cross-linkerlCo- Example 21 (Code Example 22 (Code Example 23~ (Code Example 24 (Code r D 1omer W 75066) W 75069) W 76164) W 76165) ''-A-15EO 0.4 '--A-3EO o 3 PE- ~o-r~ 0.14 M-~ EO-A 0.2 ~ ~.2 0.4 0.4 T /IP''A .' I\ PEI31000MA 3.5 ;~. ~ 2.9 1.67 Product properties (re-clross- inked) R~-er t on 'g/g] 6~.5 3~,.5 3A ~ .5 A J ~ [9~9] ' ~-5 2 26.5 AJ I 8acc. ~ 20 1 '~
SDO'~ lg/g]
MP _ 1 A?~4 l9/9] 6.5 1- "3.5 AAP . ) A~4 [%] 3 6 2 1h ~~] 3.0 .5 2.~ .5 A 16h [ ~O] 8.2 ~.3 6.~ .5 *: Example 24 was carried out wi-hout the addHion of sodium carbonate Example 25 - 30 According to the general formulation of Examples 4 - 20 further superabsorbent polymers according to the present invention were produced using triallylamine as cross-linker component lll. In Example 27, 0.4 9 sodium carbonate were added after neutralization of the acrylic acid. The results are shown in Table 4.
Example 31 According to the general formulation of Example 1 a test was carried out with a cross-linker/monomer combination of 2.5%-wt. methoxypolyethylene glycol(22EO)-methaclylate, 0.35C~o-wt. polyethylene glycol(10EO)-monoallyl ether-acrylate, and 0.12%-wt. triallylamine. The starting product had a retention of 38 9/9, the re-cross-linked product had a retention of 32.5 g/g, an AIJL (63 g/cm2) of 26.5 9/9, an AUL according to SDOV of 20 9/9, a swelling pressure of 1340 g (afler 20'), and 1080 9 (after 2h), and 6.4% soluble contents (after 16h).
Comparative Example 9 and Examples 32 - 34 These examples show the improved permeability in the swollen gel layer by using methoxypolyethylene glycol methacrylate as comonomer. The results are summarked in Table 5.
Exan1ple 32 According to the general formulation of Example 1 a test was carried out using a cross-linkellmonomer combination of 1 %-wt. methoxypolyethylene glycol(17EO)-methacrylate, 0.3%-wt.
CA 02236~04 1998-0~-20 polye!thylene glycol(10EO)-",onoal:yl ether acrylate and 0.1 %-wt. 3-EO-trimethylolpropane triacrylate. The starting product had a retention of 37.5 gtg the re-cross-linked product had a retention of 32.5 g/g an AUL (63 g/cmV of 23.5 g/g and 8.5% soluble contents (after 16h).
Exannple 33 According to the general formulation of Example 1 a test was carried out using a cross-linkellmonomer combination of 2%-wt. methoxypolyethylene glycol(17EO)-methacrylate 0.3%-wt.
polyethylene glycol(10EO)-monoallyl ether acrylate and 0.1 %-wt. 3-EO-l,i"~eti"rlolpropane triacrylate. The starting product had a retention of 37.5 9/9 the re-cross-linked product had a retention of 31.5 9/9 an AUL (63 g/cm2) of 24.5 9/9 and 8.5% soluble contents (after 16h).
Exannple 34 According to the general formulation of Example 1 a test was carried out using a cross-linke,/mono",er combination of 3%-wt. mell,oxypolyethylene glycol(17EO)-methacrylate 0.3%-wt.
polyethylene glycol(10EO)-monoallyl ether acrylate and 0.1 %-wt. 3-EO-lri",ell"~lolpropane triacrylate. The s~,li"g product had a retention of 39 g/g the re-cross-linked product had a retention of 32 g/g an AUL (63 g/cmV of 23.5 9/9 and 6.5% soluble contents (after 1 6h).
Comparative ExamPle 9 According to the general formulation of Example 1 a test was carried out using a cross-Iinker/monomer cGn,t nation without methoxypolyethylene glycol(17EO)-methacrylate and consisting of 0.3%-wt. polyethylene glycol(10EO)-monoallyl ether acrylate and 0.1 %-wt. 3-EO-trimethylolpropane triacrylate. The starting product had a retention of 33 9/9 the re-cross-linked product had a retention of 32 9/9 an AUL (63 g/cm2) of 19.5 9/9 and 7.6% soluble contents (after 16h) Comparative Examples 10 -12 The MP50-A34 value is determined in commercially available superabsorbers. The measured values prove that the products do not reach the limiting values demanded according to the present invention (Table 6).
tD C~l ~ I' OO C~ N
~ _ S~ ~
,_ _ ~0 0 0 ~ ~ o ~
~r a~ cn ~ ~ ~; G u') ~ ~ ~ ~ C
,C _ l~ O ~I C~l C~î C"l O
c~ N 1-~
o ~ ~ ~ ~ C~ î ~~) t~ O
a~
' ~~ ~ ~ ~ ~ o ~ ~ o o a) ~ ~ o ~
a~ O ~ ~ c ~ U~ ~
o _ 2 C.~o C~ --o 3~ E _ C ~ C~ O
o O
_--o--~" o ~ o O O C~l oO E o , ~ ~O O o o o O ~ ~
$ ~ E ~ E E
. ~
a) O o o~ U~ ~ ~ ~
C a ~ ~ ~ o a) ~ ~' o~ a) o ~ ~
-o o ~ o o o c~
~ o n U~ ~
~_ .o _ ~o ~~ ~ 5 E ~ 3 c~ l o c~ o ~~ ~ E
Co ~ ~ Se ~ ~ ~ o ~~ ~ ~ ~ ~ ~ O
Q ~ ,c ~
O O O O O O C~ O o o C~ o C
~ ~ ~'I ~' E ~ ~ ~ o o ~
-- o a~ a~
~e ~ 0 0 C ~ ~ ~ ~ U~
.o ~ ~ o o o o ~ U~
~-'' Q ~ ~ ~ ~ ~ O
Q ~ ~ ~ ~ ~ 0 tD a~
a~
7 ,c ~O ~
~ CO 0 o~
C ,c 1~3 E
2 c~ ''' o o ~ o o ~
C ~ O o n 'D ~ ~ 0 ' I_ I Cl ~ C~ N ~ N C~ 3 o' .3 ~_ ~ ~ ~ '~ ~ ~ ~ C~i ~a~ ~ C
tY 3~ ~' ' ,c C ~ ~- _ ~ Q
o o c~ w O o O ~
~ ~ '_ _~ c 4- 0 E '~ ~ o ~ ~ ~t, $ ~ ~ ~ ~ ~
~~ ~ as c ~ ~, ~ -~ o ~ ~
~ ~ C~l C~l C~l C~l N ~ ~ ~
Cl_ o o O O o o ~ U~ o , ~ ' ~N
E a~
~ Q ~ ~ 0 ~ O
li3 0 ~ ~ ~ ~ C'~
o u~
_ ~ ~ U~
C~
~ 2' Qo ~~~ 2 o o~ .
Q Q ~ O
N ~
-- O
~' 3 2 ~
L 10 ~ N N C~l C"
N c~ N CD N N U~
6 0 ~
~ ~ N ~ N ~ ~ ~ ~ o C
n~ ~3 ~ O
O .0 ~ o 2 >
~~ C~ o _ ~ ~ ~ c = ~ a ~ a E o ~ N N C~l N N N c C g w S '-O ~ O
C ~ O C W ~
.~ ~ ~ ~ ~ ~. _--V ~ F ~ ~ 5 ~n ~ O O O O ~ I O O
.. ._ ' O ~
u~ ~ r~ oo 0 0 111 N N C~.l N N ~) 1-- ~ ~
o O
a~ ~
o o n ~ L~ O
o o ~ ~ ~ ~
C ~) C" 1~ ~ 0,e3 lji 0 ~ O
E ~ ~ o ~ ''1 ''' ~ ' ~
2 o ~
O -- ~ ~ a~
o o o o _ o , O ~_ o o o o ~
E E ~ "~
Table 6 Example Commcrcial Product AAP50-A34l~/~] AAP50-A34r~1 Comp. 10Salsorb CL20 8.5 63 Comp. 11ASAP2000 14 74 Comp. 12Sanwet IM7000 6.5 43
Claims (23)
1. A cross-linked polymer absorbing watery liquids, built-up of partially neutralized monomers having monoethylenically unsaturated acid groups, optionally further monomers copolymerizable therewith, as well as polymers optionally suitable as graft basis, characterized in that it can be manufactured by using a cross-linker/monomer combination of I. CH2=CHR6-CO-(OCHR3-CHR3)zO-CH2-CHR6=CH2 II. CH2=CHR6-R5-(OCHR3-CHR3)vOR4 III. R1-[O(CHR3-CHR3O)u-CO-R2]x, and/or di- or triallylamine and/or bisacrylamide with R1: multivalent C2-10-alkyl, R2: linear or branched C2-10-alkenyl, R3: H, CH3, C2H5, R4: H, linear or branched C1-10-alkyl, R5: CO, CH2 R6: H, CH3, x: 2-6, u: 0-15 v: 1-45 z: 3-20
2. Polymer as in claim 1, characterized by the fact that the components are used I) with 0 - 1.0 % by weight, preferably with 0.05 - 1.0 % by weight II) with 0.1 - 10 % by weight, preferably with 0.5 - 5 % by weight and III) with 0.01 - 1.0 % by weight, preferably with 0.05 to 0.6 % by weight relative to the monomers.
3. Polymer as in claim 1, characterized by the fact that the cross-linkers are used I) with 0.1 - 0.4 % by weight II) with 1.0 - 3.5 % by weight and III) with 0.05 - 0.3 % by weight relative to the monomers.
4. Polymer as in claims 1 to 3, characterized by the fact that the cross-linkers under I are selected from the group of allyl polyethylene glycol-(meth)acrylic acid ester, the monomers under II from the group of methyl polyethylene glycol-(meth)acrylates, and the cross-linkers under III from the group of trimethylolpropane oxethylate-(meth)acrylic acid esters, glycerol oxethylate-(meth)acrylic acid esters, pentaerythritol oxethylate-(meth)acrylic acid esters, polyethylene glycol-.alpha.,.omega.-di(meth)acrylic acid esters and di- or triallylamine, N,N-methylenebisacrylamide and bisacrylamido acetic acid.
5. Polymer according to claims 1 to 4, characterized by the fact that the monomers bearing unsaturated acid groups are selected from the group acrylic acid, methacrylic acid, vinyl acetic acid, vinyl sulfonic acid, methallyl sulfonic acid and 2-acrylamido-2-methyl propane sulfonic acid.
6. Polymer according to claims 1 to 5, characterized by the fact that it comprises incorporated by polymerization 0 to 40 % by weight further comonomers from the group (meth)acrylamide, (meth)acrylonitrile, vinyl pyrrolidone, hydroxy ethyl acrylate and vinyl acetamide.
7. Polymer according to claims 1 to 6, characterized by the fact that it contains up to 30 % by weight of water-soluble polymers as a graft basis, preferably polysaccharides and/or polyvinyl alcohol.
8. Polymer according to claims 1 to 7, characterized by the fact that it has been cross-linked on the surface with a re-cross-linking agent and that this re-cross-linkage has optionally been repeated many times.
9. Polymer according to claim 8, characterized by the fact that it has been cross-linked on the surface with a re-cross-linking agent from the group of polyoles, polyepoxides, polyamines or alkylene carbonates.
10. Polymer according to claims 8 and 9, characterized by the fact that it has a retention of at least 30 g/g, a liquid up-take under pressure (63 g/cm2) of at least 20 g/g and a liquid up-take under pressure (63 g/cm2) after SDOV of at least 18 g/g, as well as soluble components after 1 hour of a maximum of 6.5 % and after 16 hours of a maximum of 10 %, as well as an absorption against a pressure of 50 g/cm2 with a suction surface reduced by 34% (AAP-A34) of at least 15 g/g, as well as at least 50% of the initial value of the absorption against pressure without surface reduction.
11. Polymer according to claims 8, 9 and 10, characterized by the fact that H has a liquid take-up under pressure (63 g/cm2) after SDOV of at least 20 g/g, preferably of at least 22 g/g, and an AAP-A34 of at least 20 g/g.
12. Polymer according to claims 8, 9 and 10, characterized by the fact that it has a swelling pressure (20 minutes) of at least 600 g, preferably of at least 800 g, more preferably of greater than 900 g.
13. Polymer according to claims 8, 9 and 10, characterized by the fact that the soluble components after 16 hours amount to a maximum of 8 %.
14. Polymer according to claims 8, 9 and 10, characterized by the fact that it has a liquid take-up under pressure (63 g/cm2) of greater than 23 g/g and preferably of greater than 25 g/g.
15. Polymer according to claims 8, 9 and 10, characterized by the fact that the rate of liquid take-up is less than 40 seconds, preferably less than 35 seconds and more preferably less than 30 seconds.
16. Process for the manufacture of a cross-linked polymer absorbing watery liquids according to claims 1 to 7, characterized by the fact that a watery solution of unsaturated partly neutralized monomers bearing acid groups and a cross-linker mixture of I. CH2=CHR6-CO-(OCHR3-CHR3)zO-CH2-CHR6=CH2 II. CH2=CHR6-R5-(OCHR3-CHR3)vOR4 III. R1-[O(CHR3-CHR3O)u-CO-R2]x, and/or di- or triallylamine and/or bisacrylamide with R1: multivalent C2-10-alkyl, R2: linear or branched C2-10-alkenyl, R3: H, CH3, C2H5, R4: H, linear or branched C1-10-alkyl, R5: CO, CH2, R6: H, CH3, x: 2-6 u: 0-15 v: 1-45 z: 3-20 with the addition of radical forming agents according to the process of a solution or suspension polymerization is polymerized to a hydrogel, crushed, dried, ground and sieved.
17. Process according to claim 16, characterized by the fact that the polymers are treated with a surface cross-linking agent and surface cross-linkage is carried out at a raised temperature.
18. Process according to claim 17, characterized by the fact that the surface treatment and cross-linkage is carried out several times.
19. Use of the polymers according to claims 1 to 15 as absorption agent for water and watery liquids.
20. Use of polymers according to claims 1 to 13 in structures for the absorption of body fluids.
21. Use of polymers according to claims 1 to 15 as a component for absorbing water or watery liquids in electricity or light conducting cables, as a component in packing materials, as a ground improving agent and in plant raising.
22. Use of polymers according to claims 1 to 15 in foamed or non-foamed layers which absorb water or watery liquids.
23. Use of polymers according to claims 1 to 15 as a carrier substance for fertilizer or other active ingredients which are given off slowly to the environment over a prolonged period.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19543369.6 | 1995-11-21 | ||
| DE19543369 | 1995-11-21 | ||
| DE19646484A DE19646484C2 (en) | 1995-11-21 | 1996-11-11 | Liquid absorbing polymers, processes for their production and their use |
| DE19546484.6 | 1996-11-11 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2236504A1 true CA2236504A1 (en) | 1997-05-29 |
Family
ID=26020546
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002236504A Abandoned CA2236504A1 (en) | 1995-11-21 | 1996-11-18 | Fluid-absorbing polymers, process for the preparation and use thereof |
Country Status (17)
| Country | Link |
|---|---|
| US (1) | US5837789A (en) |
| EP (1) | EP0862590B1 (en) |
| JP (1) | JP4001350B2 (en) |
| KR (1) | KR100444022B1 (en) |
| CN (1) | CN1106415C (en) |
| AT (1) | ATE183526T1 (en) |
| AU (1) | AU718132B2 (en) |
| BR (1) | BR9611469A (en) |
| CA (1) | CA2236504A1 (en) |
| DE (2) | DE19646484C2 (en) |
| ES (1) | ES2138385T3 (en) |
| MX (1) | MX202050B (en) |
| PL (1) | PL326840A1 (en) |
| RU (1) | RU2193045C2 (en) |
| TR (1) | TR199800900T2 (en) |
| TW (1) | TW438821B (en) |
| WO (1) | WO1997019116A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8383746B2 (en) | 2006-03-27 | 2013-02-26 | Nippon Shokubai Co., Ltd | Water absorbing resin with improved internal structure and manufacturing method therefor |
Families Citing this family (325)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1997024394A1 (en) † | 1995-12-27 | 1997-07-10 | Nippon Shokubai Co., Ltd. | Water absorbent and process and equipment for the production thereof |
| CA2259476A1 (en) * | 1996-07-06 | 1998-01-15 | Stockhausen Gmbh & Co. Kg | Absorbent inserts, method of producing them and their use |
| US6596532B1 (en) | 1997-12-12 | 2003-07-22 | BIOMéRIEUX, INC. | Device for isolation and surface culture of microorganisms from bulk fluids |
| RU2212722C2 (en) * | 1998-10-07 | 2003-09-20 | Пирелли Кави Э Системи С.П.А. | Water-resistant cable |
| US6297335B1 (en) * | 1999-02-05 | 2001-10-02 | Basf Aktiengesellschaft | Crosslinked, hydrophilic, highly swellable hydrogels, production thereof and use thereof |
| DE19909653A1 (en) | 1999-03-05 | 2000-09-07 | Stockhausen Chem Fab Gmbh | Powdery, crosslinked, aqueous liquids and blood-absorbing polymers, processes for their preparation and their use |
| AUPP939299A0 (en) * | 1999-03-23 | 1999-04-15 | University Of Melbourne, The | Polymer gels and methods for their preparation |
| EP1069142B1 (en) * | 1999-07-15 | 2010-04-28 | Clariant Produkte (Deutschland) GmbH | Water soluble polymers and their use in cosmetic and pharmaceutic products |
| DE19941423A1 (en) * | 1999-08-30 | 2001-03-01 | Stockhausen Chem Fab Gmbh | Polymer composition and a process for its production |
| DE50102334D1 (en) | 2000-03-31 | 2004-06-24 | Stockhausen Chem Fab Gmbh | POWDERED POLYMERISATE CROSSLINED ON THE SURFACE |
| MXPA02009484A (en) * | 2000-04-01 | 2003-03-10 | Qinetiq Ltd | Polymers. |
| DE10037629A1 (en) * | 2000-08-02 | 2002-02-14 | Skw Bauwerkstoffe Deutschland | Water-soluble or water-swellable sulfo-containing associative thickening copolymers, process for their preparation and their use |
| DE10043710B4 (en) | 2000-09-04 | 2015-01-15 | Evonik Degussa Gmbh | Use of powdery postcrosslinked polymers and hygiene articles |
| US6903243B1 (en) * | 2000-09-08 | 2005-06-07 | 3M Innovative Properties Company | Multi-layer absorbent wound dressing |
| ES2234902T3 (en) * | 2000-10-19 | 2005-07-01 | Basf Aktiengesellschaft | WATERPROOF RITICULATED POLYMER IN WATER AND PROCEDURE FOR MANUFACTURING. |
| US6403674B1 (en) | 2000-11-17 | 2002-06-11 | Eveready Battery Company, Inc. | Solvent-free method for synthesizing superabsorbent polymers |
| AU2002218089A1 (en) * | 2000-11-20 | 2002-05-27 | Matrix Innovation Inc. | Amphiphile solid support for peptide synthesis, bioorganic and organic chemistry |
| DE10059832A1 (en) * | 2000-12-01 | 2002-06-13 | Clariant Gmbh | Grafted copolymers based on acryloyldimethyltauric acid |
| DE10059830A1 (en) * | 2000-12-01 | 2002-06-13 | Clariant Gmbh | Cationically modified comb polymers based on acryloyldimethyltauric acid |
| DE10059821A1 (en) * | 2000-12-01 | 2002-06-13 | Clariant Gmbh | Surfactant-free cosmetic, dermatological and pharmaceutical agents |
| DE10059829A1 (en) * | 2000-12-01 | 2002-06-13 | Clariant Gmbh | Grafted comb polymers based on acryloyldimethyltauric acid |
| DE10059828A1 (en) * | 2000-12-01 | 2002-06-13 | Clariant Gmbh | Comb-shaped copolymers based on acryloyldimethyltauric acid |
| DE10059819A1 (en) * | 2000-12-01 | 2002-06-13 | Clariant Gmbh | Surfactant-containing cosmetic, dermatological and pharmaceutical agents |
| US6998367B2 (en) | 2001-12-06 | 2006-02-14 | Kimberly-Clark Worldwide, Inc. | Absorbent composition containing transitional crosslinking points |
| CN1279067C (en) * | 2001-12-19 | 2006-10-11 | 株式会社日本触媒 | Acrylic acid composition, method of manufacturing the same, method of manufacturing water-absorbing resin using the same and water-soluble resin |
| DE10163543A1 (en) * | 2001-12-21 | 2003-07-31 | Basf Ag | Super absorber containing tocopherol |
| DE10163902A1 (en) * | 2001-12-22 | 2003-07-03 | Clariant Gmbh | Crystallization inhibitor for crop protection formulations |
| US7101946B2 (en) * | 2002-02-14 | 2006-09-05 | Stockhausen Gmbh | Water-absorbing polymers having interstitial compounds, a process for their production, and their use |
| DE10225943A1 (en) * | 2002-06-11 | 2004-01-08 | Basf Ag | Process for the preparation of esters of polyalcohols |
| WO2003104301A1 (en) * | 2002-06-11 | 2003-12-18 | Basf Aktiengesellschaft | (meth)acrylic esters of polyalkoxylated glycerine |
| AU2003238490A1 (en) * | 2002-06-11 | 2003-12-22 | Basf Aktiengesellschaft | (meth)acrylic esters of polyalkoxylated trimethylolpropane |
| PL374441A1 (en) * | 2002-06-11 | 2005-10-17 | Basf Aktiengesellschaft | (meth)acrylic esters of polyalkoxylated trimethylolpropane |
| EP1563002B2 (en) | 2002-10-25 | 2017-12-13 | Evonik Degussa GmbH | Absorbent polymer structure provided with an improved retention capacity and permeability |
| DE10249822A1 (en) * | 2002-10-25 | 2004-05-13 | Stockhausen Gmbh & Co. Kg | A two-stage process for preparation of an absorbing polymer useful for foams, sealing materials, liquid absorbing hygiene articles, plant growth regulators, packaging materials, and floor covering additives |
| ES2428693T3 (en) | 2003-02-12 | 2013-11-08 | The Procter & Gamble Company | Absorbent core for an absorbent article |
| ATE523180T1 (en) | 2003-02-12 | 2011-09-15 | Procter & Gamble | ABSORBENT CORE FOR AN ABSORBENT ARTICLE |
| CN1784436B (en) * | 2003-03-07 | 2010-06-02 | 巴斯福股份公司 | Polymer products |
| US7528291B2 (en) | 2003-03-26 | 2009-05-05 | Basf Aktiengesellschaft | Color-stable superabsorbent polymer composition |
| DE10314599A1 (en) * | 2003-03-31 | 2004-10-21 | Mang, Thomas, Prof. Dr. | Use of a cross-linked polymer composition as a water-absorbing component in sealing and absorption materials |
| DE10358372A1 (en) * | 2003-04-03 | 2004-10-14 | Basf Ag | Trimethylolpropane esters are useful for the production of cross-linked hydrogels, useful for the production of hygiene articles, packaging materials and non-wovens |
| JP4460851B2 (en) * | 2003-05-27 | 2010-05-12 | 株式会社日本触媒 | Method for sizing water-absorbent resin |
| RU2333229C2 (en) | 2003-06-24 | 2008-09-10 | Ниппон Шокубаи Ко., Лтд. | Water-absorbing resin-based composition, methods for obtaining same (versions), absorber and absorbing device based thereon |
| DE10331456A1 (en) | 2003-07-10 | 2005-02-24 | Basf Ag | (Meth) acrylic esters of alkoxylated unsaturated polyol ethers and their preparation |
| DE10331450A1 (en) * | 2003-07-10 | 2005-01-27 | Basf Ag | (Meth) acrylic esters of monoalkoxylated polyols and their preparation |
| MXPA06001295A (en) | 2003-08-06 | 2006-04-11 | Procter & Gamble | Absorbent article comprising coated water-swellable material. |
| WO2005014697A1 (en) | 2003-08-06 | 2005-02-17 | The Procter & Gamble Company | Coated water-swellable material |
| EP1651282A1 (en) | 2003-08-06 | 2006-05-03 | The Procter & Gamble Company | Absorbant structures comprising coated water-swellable material |
| EP1518567B1 (en) | 2003-09-25 | 2017-06-28 | The Procter & Gamble Company | Absorbent articles comprising fluid acquisition zones with coated superabsorbent particles |
| DE10355401A1 (en) | 2003-11-25 | 2005-06-30 | Basf Ag | (Meth) acrylic esters of unsaturated amino alcohols and their preparation |
| DE102004019264B4 (en) * | 2004-04-21 | 2008-04-10 | Stockhausen Gmbh | Process for the preparation of an absorbent polymer by means of spread drying |
| DE102004051242A1 (en) | 2004-10-20 | 2006-05-04 | Basf Ag | Finely divided water-absorbing polymer particles with high liquid transport and absorption performance |
| DE102004055765A1 (en) | 2004-11-18 | 2006-05-24 | Basf Ag | Process for the preparation of water-absorbing polymers |
| CA2492884A1 (en) * | 2005-01-13 | 2006-07-13 | Stephane Chevigny | A high efficiency process for particle size reduction of glass-like polysaccharides |
| DE102005002412A1 (en) * | 2005-01-18 | 2006-07-27 | Basf Ag | Process for the preparation of polymers by spray polymerization |
| US20080154224A1 (en) * | 2005-02-04 | 2008-06-26 | Basf Aktiengesellschaft | Process for Producing a Water-Absorbing Material Having a Coating of Elastic Filmforming Polymers |
| JP2008529590A (en) * | 2005-02-04 | 2008-08-07 | ザ プロクター アンド ギャンブル カンパニー | Absorbent structure with improved water-absorbing material |
| WO2006082239A2 (en) * | 2005-02-04 | 2006-08-10 | Basf Aktiengesellschaft | Water-absorbing material having a coating of elastic film-forming polymers |
| TW200635959A (en) * | 2005-02-04 | 2006-10-16 | Basf Ag | Water swellable material |
| DE602006015422D1 (en) * | 2005-02-04 | 2010-08-26 | Basf Se | METHOD FOR PRODUCING A WATER ABSORBENT MATERIAL WITH A COATING OF ELASTIC FILM-FORMING POLYMERS |
| DE102005014291A1 (en) | 2005-03-24 | 2006-09-28 | Basf Ag | Process for the preparation of water-absorbing polymers |
| TWI344469B (en) | 2005-04-07 | 2011-07-01 | Nippon Catalytic Chem Ind | Polyacrylic acid (salt) water-absorbent resin, production process thereof, and acrylic acid used in polymerization for production of water-absorbent resin |
| US20060264861A1 (en) | 2005-05-20 | 2006-11-23 | Lavon Gary D | Disposable absorbent article having breathable side flaps |
| DE102005042604A1 (en) | 2005-09-07 | 2007-03-08 | Basf Ag | Neutralization process |
| TWI394789B (en) | 2005-12-22 | 2013-05-01 | Nippon Catalytic Chem Ind | Water-absorbent resin composition, method of manufacturing the same, and absorbent article |
| TWI377222B (en) | 2005-12-22 | 2012-11-21 | Nippon Catalytic Chem Ind | Method for surface crosslinking water-absorbing resin and method for manufacturing water-absorbing resin |
| US20090012486A1 (en) * | 2005-12-28 | 2009-01-08 | Basf Se | Process for Production of a Water-Absorbing Material |
| EP1837348B9 (en) | 2006-03-24 | 2020-01-08 | Nippon Shokubai Co.,Ltd. | Water-absorbing resin and method for manufacturing the same |
| EP1840137B1 (en) | 2006-03-29 | 2009-11-25 | Nippon Shokubai Co., Ltd. | Method of Producing Polyacrylic Acid (Salt) Water-Absorbent Resin |
| BRPI0711452B8 (en) | 2006-04-21 | 2021-06-22 | Evonik Degussa Gmbh | process for preparing a water-absorbing polymeric structure, water-absorbing polymeric structure, composite, process for preparing a composite, use of the water-absorbent polymeric structure or use of the composite and use of a salt |
| US8734559B2 (en) | 2006-09-07 | 2014-05-27 | Biolargo Life Technologies, Inc. | Moderation of animal environments |
| US8757253B2 (en) | 2006-09-07 | 2014-06-24 | Biolargo Life Technologies, Inc. | Moderation of oil extraction waste environments |
| DE502007003544D1 (en) * | 2006-10-19 | 2010-06-02 | Basf Se | PROCESS FOR PREPARING SUPER ABSORBERS |
| DE102008000237A1 (en) | 2007-02-06 | 2008-08-07 | Basf Se | Mixtures, useful e.g. as an inhibitor or retarder for the stabilization of polymerizable compound, preferably swellable hydrogel-forming polymers, comprises a phenol imidazole derivative and a polymerizable compound |
| FR2916355B1 (en) * | 2007-05-25 | 2009-08-28 | Urgo Soc Par Actions Simplifie | NEW ACTIVE INGREDIENT IN HEALING AND ITS USE |
| ES2443535T3 (en) | 2007-06-18 | 2014-02-19 | The Procter & Gamble Company | Disposable absorbent article with substantially continuous continuously distributed particle-shaped polymeric material and method |
| CN101677892B (en) | 2007-06-18 | 2014-03-12 | 宝洁公司 | Disposable absorbent article with sealed absorbent core with substantially continuously distributed absorbent particulate polymer material |
| EP2018876A1 (en) * | 2007-07-27 | 2009-01-28 | The Procter and Gamble Company | Absorbent article comprising water-absorbing polymeric particles and method for the production thereof |
| US7989401B2 (en) * | 2008-04-21 | 2011-08-02 | Nalco Company | Block copolymers for recovering hydrocarbon fluids from a subterranean reservoir |
| WO2009134780A1 (en) | 2008-04-29 | 2009-11-05 | The Procter & Gamble Company | Process for making an absorbent core with strain resistant core cover |
| US20090318884A1 (en) * | 2008-06-20 | 2009-12-24 | Axel Meyer | Absorbent structures with immobilized absorbent material |
| DE102008030712A1 (en) * | 2008-06-27 | 2009-12-31 | Construction Research & Technology Gmbh | Time-delayed superabsorbent polymers |
| EP2163266A1 (en) | 2008-09-12 | 2010-03-17 | The Procter & Gamble | Absorbent article comprising water-absorbing material |
| SG194348A1 (en) * | 2008-09-16 | 2013-11-29 | Nippon Catalytic Chem Ind | Production method and method for enhancing liquid permeability of water-absorbing resin |
| EP2204431A1 (en) * | 2008-12-18 | 2010-07-07 | Basf Se | Method for blocking subterranean formations |
| JP5600670B2 (en) | 2009-02-17 | 2014-10-01 | 株式会社日本触媒 | Polyacrylic acid water-absorbing resin powder and method for producing the same |
| US8608096B2 (en) | 2009-02-18 | 2013-12-17 | Basf Se | Method for the production of water-absorbing polymer particles |
| US20100247916A1 (en) | 2009-03-24 | 2010-09-30 | Basf Se | Process for Producing Surface Postcrosslinked Water-Absorbing Polymer Particles |
| WO2010124954A1 (en) | 2009-04-30 | 2010-11-04 | Basf Se | Method for removing metal impurities |
| US20120064792A1 (en) | 2009-05-20 | 2012-03-15 | Basf Se | Water Absorbent Storage Layers |
| US8502012B2 (en) * | 2009-06-16 | 2013-08-06 | The Procter & Gamble Company | Absorbent structures including coated absorbent material |
| US8410221B2 (en) | 2009-06-26 | 2013-04-02 | Basf Se | Process for producing water-absorbing polymer particles with low caking tendency and high absorption under pressure |
| RU2541564C9 (en) | 2009-07-15 | 2015-11-20 | Басф Се | Mixtures containing oligomeric or polymeric compounds, production and use thereof |
| EP2277557B1 (en) | 2009-07-20 | 2014-06-25 | The Procter and Gamble Company | Coated superabsorbent polymer particles and processes therefore |
| EP2277558B1 (en) | 2009-07-20 | 2014-07-02 | The Procter and Gamble Company | Superabsorbent polymer composite particles and processes therefore |
| CN102481387B (en) | 2009-08-25 | 2014-10-01 | 巴斯夫欧洲公司 | Method for producing water-absorbing polymer particles having improved blood absorption by polymerising droplets of a monomer solution |
| JP2013503214A (en) | 2009-08-25 | 2013-01-31 | ビーエーエスエフ ソシエタス・ヨーロピア | Soft granular superabsorbent and use thereof |
| CN105854063A (en) | 2009-08-26 | 2016-08-17 | 巴斯夫欧洲公司 | Odor-Inhibiting Compositions |
| EP2470226A1 (en) | 2009-08-28 | 2012-07-04 | Basf Se | Process for producing triclosan-coated superabsorbents |
| US8481159B2 (en) | 2009-09-04 | 2013-07-09 | Basf Se | Water-absorbent porous polymer particles having specific sphericity and high bulk density |
| CN102597082A (en) | 2009-09-16 | 2012-07-18 | 巴斯夫欧洲公司 | Color-stable superabsorber |
| EP2477664A1 (en) | 2009-09-17 | 2012-07-25 | Basf Se | Color-stable superabsorber |
| CN102498167A (en) | 2009-09-18 | 2012-06-13 | 巴斯夫欧洲公司 | Open-cell foams having superabsorbers |
| CN102548654A (en) | 2009-09-29 | 2012-07-04 | 株式会社日本触媒 | Particulate water absorbent and process for production thereof |
| US20120184690A1 (en) | 2009-10-09 | 2012-07-19 | Basf Se | Method for Continuous Production of Water-Absorbent Polymer Particles |
| JP5794991B2 (en) | 2009-10-09 | 2015-10-14 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Use of heated vapor condensate to produce water-absorbing polymer particles |
| EP2486084B1 (en) | 2009-10-09 | 2016-03-23 | Basf Se | Process for remoisturizing surface-postcrosslinked water-absorbing polymer particles |
| WO2011042468A2 (en) | 2009-10-09 | 2011-04-14 | Basf Se | Method for re-wetting surface post-cross-linked, water-absorbent polymer particles |
| EP2496343A1 (en) | 2009-11-06 | 2012-09-12 | Basf Se | Textiles comprising improved superabsorbers |
| JP2013509963A (en) | 2009-11-09 | 2013-03-21 | スポットライト テクノロジー パートナーズ エルエルシー | Fragmented hydrogel |
| CN102695500A (en) | 2009-11-09 | 2012-09-26 | 聚光灯技术合伙有限责任公司 | Polysaccharide based hydrogels |
| EP2504368B1 (en) | 2009-11-23 | 2014-01-08 | Basf Se | Method for producing water-absorbing polymer particles having improved color stability |
| CN102665772B (en) * | 2009-11-23 | 2016-08-03 | 巴斯夫欧洲公司 | The method preparing water absorbent polymer foam |
| JP2013511612A (en) | 2009-11-23 | 2013-04-04 | ビーエーエスエフ ソシエタス・ヨーロピア | Method for producing foamed water-absorbing polymer particles |
| EP2329803B1 (en) | 2009-12-02 | 2019-06-19 | The Procter & Gamble Company | Apparatus and method for transferring particulate material |
| CN102712712B (en) | 2009-12-24 | 2015-05-06 | 株式会社日本触媒 | Water-absorbable polyacrylic acid resin powder, and process for production thereof |
| US10182946B2 (en) | 2009-12-24 | 2019-01-22 | Liberman Distributing And Manufacturing Co. | Advanced fabric technology and filters |
| US9901128B2 (en) * | 2009-12-24 | 2018-02-27 | David A. Gray | Antimicrobial apparel and fabric and coverings |
| WO2011092098A1 (en) | 2010-01-27 | 2011-08-04 | Basf Se | Odor-inhibiting, water-absorbing composite materials |
| EP2539382B1 (en) | 2010-02-24 | 2014-10-22 | Basf Se | Method for producing water-absorbing polymer particles |
| EP2539381A1 (en) | 2010-02-24 | 2013-01-02 | Basf Se | Method for producing water-absorbing polymer particles |
| US8703876B2 (en) | 2010-03-15 | 2014-04-22 | Basf Se | Process for producing water absorbing polymer particles with improved color stability |
| EP2547703A1 (en) | 2010-03-15 | 2013-01-23 | Basf Se | A process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution |
| EP2550306B1 (en) | 2010-03-24 | 2014-07-02 | Basf Se | A process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution |
| WO2011117215A1 (en) | 2010-03-24 | 2011-09-29 | Basf Se | Method for removing residual monomers from water-absorbent polymer particles |
| CN102905661B (en) | 2010-03-24 | 2016-09-07 | 巴斯夫欧洲公司 | Ultrathin Fluid-Absorbent Cores |
| EP2550316B2 (en) | 2010-03-25 | 2018-11-14 | Basf Se | Method for producing water-absorbing polymer particles |
| WO2011131526A1 (en) | 2010-04-19 | 2011-10-27 | Basf Se | Method for producing water-absorbing polymer particles |
| WO2011157656A2 (en) | 2010-06-14 | 2011-12-22 | Basf Se | Water-absorbing polymer particles with improved colour stability |
| US9962459B2 (en) | 2010-07-02 | 2018-05-08 | Basf Se | Ultrathin fluid-absorbent cores |
| CN103002941B (en) | 2010-07-02 | 2016-02-03 | 利伯曼分配及制造公司 | For the method and structure of nasal dilator |
| US9089624B2 (en) | 2010-08-23 | 2015-07-28 | Basf Se | Ultrathin fluid-absorbent cores comprising adhesive and having very low dry SAP loss |
| EP2625207A1 (en) | 2010-10-06 | 2013-08-14 | Basf Se | Method for producing thermally surface post-crosslinked water-absorbing polymer particles |
| EP2464680B1 (en) | 2010-10-21 | 2013-10-02 | The Procter & Gamble Company | Absorbent structures comprising post-crosslinked water-absorbent particles |
| EP2630183A1 (en) | 2010-10-21 | 2013-08-28 | Basf Se | Water-absorbing polymeric particles and method for the production thereof |
| EP2447286A1 (en) | 2010-11-01 | 2012-05-02 | The Procter & Gamble Company | Process using supercritical medium to produce polymers |
| EP2476714A1 (en) | 2011-01-13 | 2012-07-18 | Basf Se | Polyurethane integral foams with improved surface hardness |
| WO2012107344A1 (en) | 2011-02-07 | 2012-08-16 | Basf Se | Method for producing water-absorbing polymer particles |
| EP2673011B2 (en) | 2011-02-07 | 2019-01-16 | Basf Se | Procedure for preparing water absorbing polymer particles having high free swell rate |
| DE102011003882A1 (en) | 2011-02-09 | 2012-08-09 | Sb Limotive Company Ltd. | Composition for extinguishing and / or inhibiting fluorinated and / or phosphorus-containing fires |
| DE102011003877A1 (en) | 2011-02-09 | 2012-08-09 | Sb Limotive Company Ltd. | Composition for extinguishing and / or inhibiting fluorinated and / or phosphorus-containing fires |
| CN103415553B (en) | 2011-03-08 | 2015-07-08 | 巴斯夫欧洲公司 | Method for producing water-absorbing polymer particles having improved permeability |
| US8802786B2 (en) | 2011-04-21 | 2014-08-12 | Evonik Corporation | Particulate superabsorbent polymer composition having improved performance properties |
| EP2705075B1 (en) | 2011-05-06 | 2016-12-21 | Basf Se | Method for the production of water-absorbing polymer particles |
| US8987545B2 (en) | 2011-05-18 | 2015-03-24 | The Procter & Gamble Company | Feminine hygiene absorbent articles comprising water-absorbing polymer particles |
| WO2012156386A1 (en) | 2011-05-18 | 2012-11-22 | Basf Se | Use of water-absorbing polymer particles for dewatering faeces |
| US20120296297A1 (en) | 2011-05-18 | 2012-11-22 | Achille Di Cintio | Feminine hygiene absorbent articles comprising water-absorbing polymeric foams |
| CN103596599B (en) | 2011-05-18 | 2016-08-17 | 巴斯夫欧洲公司 | Water-absorbing polymer particles is for absorbing the purposes of blood and/or menstruation |
| WO2012156385A1 (en) | 2011-05-18 | 2012-11-22 | Basf Se | Water-absorbing composites |
| US9265855B2 (en) | 2011-05-18 | 2016-02-23 | The Procter & Gamble Company | Feminine hygiene absorbent article comprising a superabsorbent foam of high swell rate |
| JP6109157B2 (en) | 2011-05-18 | 2017-04-05 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Production of superabsorbent foam with high swelling rate |
| US9149556B2 (en) | 2011-05-18 | 2015-10-06 | The Procter & Gamble Company | Feminine hygiene absorbent articles comprising water-absorbing composites |
| JP6253575B2 (en) | 2011-05-26 | 2017-12-27 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Method for producing water-absorbing polymer particles |
| EP2714103B1 (en) | 2011-05-26 | 2019-08-21 | Basf Se | Process for the continuous production of water-absorbing polymer particles |
| US8664151B2 (en) | 2011-06-01 | 2014-03-04 | The Procter & Gamble Company | Articles comprising reinforced polyurethane coating agent |
| US8999884B2 (en) | 2011-06-01 | 2015-04-07 | The Procter & Gamble Company | Absorbent structures with coated water-absorbing material |
| DE112012002289A5 (en) | 2011-06-01 | 2014-03-13 | Basf Se | Odor-inhibiting mixtures for incontinence articles |
| EP2714755B1 (en) | 2011-06-03 | 2017-04-26 | Basf Se | Method for continuous production of water-absorbent polymer particles |
| WO2012163930A1 (en) | 2011-06-03 | 2012-12-06 | Basf Se | Method for continuously producing water-absorbing polymer particles |
| WO2012170808A1 (en) | 2011-06-10 | 2012-12-13 | The Procter & Gamble Company | Absorbent core for disposable absorbent articles |
| WO2012170779A1 (en) | 2011-06-10 | 2012-12-13 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
| EP2532334B1 (en) | 2011-06-10 | 2016-10-12 | The Procter and Gamble Company | Absorbent core for disposable absorbent article |
| EP2532329B1 (en) | 2011-06-10 | 2018-09-19 | The Procter and Gamble Company | Method and apparatus for making absorbent structures with absorbent material |
| EP2717821B1 (en) | 2011-06-10 | 2019-08-07 | The Procter and Gamble Company | Disposable diapers |
| ES2484695T5 (en) | 2011-06-10 | 2018-02-13 | The Procter & Gamble Company | Disposable diaper that has a reduced joint between the absorbent core and the backing sheet |
| US10561546B2 (en) | 2011-06-10 | 2020-02-18 | The Procter & Gamble Company | Absorbent structure for absorbent articles |
| ES2459724T3 (en) | 2011-06-10 | 2014-05-12 | The Procter & Gamble Company | Method and apparatus for making absorbent structures with absorbent material |
| CA2840641A1 (en) | 2011-06-30 | 2013-01-03 | The Procter & Gamble Company | Absorbent structure comprising an oil-scavenger component |
| JP5980325B2 (en) | 2011-07-14 | 2016-08-31 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Process for producing water-absorbing polymer particles having a high swelling rate |
| WO2013045163A1 (en) | 2011-08-12 | 2013-04-04 | Basf Se | A process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution |
| ES2686023T3 (en) | 2011-10-18 | 2018-10-16 | Basf Se | Fluid absorbent article |
| EP2586409A1 (en) | 2011-10-24 | 2013-05-01 | Bostik SA | New absorbent article and process for making it |
| EP2586412A1 (en) | 2011-10-24 | 2013-05-01 | Bostik SA | New absorbent article and process for making it |
| EP2586410A1 (en) | 2011-10-24 | 2013-05-01 | Bostik SA | Novel process for preparing an absorbent article |
| DE102011117127A1 (en) | 2011-10-28 | 2013-05-02 | Basf Se | Polymers absorbing liquids and storing polymers, in particular graft polymers, processes for their preparation and their use |
| DE102011086516A1 (en) | 2011-11-17 | 2013-05-23 | Evonik Degussa Gmbh | Superabsorbent polymers with fast absorption properties and process for its preparation |
| US9126186B2 (en) | 2011-11-18 | 2015-09-08 | Basf Se | Process for producing thermally surface postcrosslinked water-absorbing polymer particles |
| WO2013076031A1 (en) | 2011-11-22 | 2013-05-30 | Basf Se | Superabsorbent polymer with pyrogenium aluminum oxide |
| US9427945B2 (en) | 2011-12-30 | 2016-08-30 | Liberman Distributing And Manufacturing Co. | Extendable self-supporting material composites and manufacture thereof |
| WO2013117496A1 (en) | 2012-02-06 | 2013-08-15 | Basf Se | Method for producing water-absorbing polymer particles |
| JP6133332B2 (en) | 2012-02-15 | 2017-05-24 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Water-absorbing polymer particles with high swelling rate and high permeability |
| CN104204039A (en) | 2012-03-30 | 2014-12-10 | 巴斯夫欧洲公司 | Method for thermal surface post-crosslinking in a drum-type heat exchanger having an inverse screw flight |
| CN104245760A (en) | 2012-03-30 | 2014-12-24 | 巴斯夫欧洲公司 | Color-stable super-absorbent |
| CN104271622B (en) | 2012-03-30 | 2017-02-22 | 巴斯夫欧洲公司 | Color-stable super-absorbent |
| EP2838572A1 (en) | 2012-04-17 | 2015-02-25 | Basf Se | Process for producing surface postcrosslinked water-absorbing polymer particles |
| WO2013156330A1 (en) | 2012-04-17 | 2013-10-24 | Basf Se | Process for producing surface postcrosslinked water-absorbing polymer particles |
| WO2013182469A2 (en) | 2012-06-08 | 2013-12-12 | Basf Se | Odour-control superabsorbent |
| EP2671554B1 (en) | 2012-06-08 | 2016-04-27 | The Procter & Gamble Company | Absorbent core for use in absorbent articles |
| JP6250042B2 (en) | 2012-06-13 | 2017-12-20 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Method for producing water-absorbing polymer particles in a polymerization reactor having at least two shafts rotating in parallel to the axis |
| EP2861633B1 (en) | 2012-06-19 | 2016-08-10 | Basf Se | Method for the production of water-absorbing polymer particles |
| EP2679208B1 (en) | 2012-06-28 | 2015-01-28 | The Procter & Gamble Company | Absorbent core for use in absorbent articles |
| EP2679209B1 (en) | 2012-06-28 | 2015-03-04 | The Procter & Gamble Company | Absorbent articles with improved core |
| EP2679210B1 (en) | 2012-06-28 | 2015-01-28 | The Procter & Gamble Company | Absorbent articles with improved core |
| WO2014005860A1 (en) | 2012-07-03 | 2014-01-09 | Basf Se | Method for producing water-absorbent polymer particles with improved properties |
| WO2014019813A1 (en) | 2012-07-30 | 2014-02-06 | Basf Se | Odour-inhibiting mixtures for incontinence products |
| CN104583241B (en) | 2012-08-27 | 2018-01-16 | 巴斯夫欧洲公司 | The method for preparing water-absorbing polymeric particles |
| CN104718228B (en) | 2012-09-19 | 2017-06-20 | 巴斯夫欧洲公司 | The method for preparing water-absorbing polymeric particles |
| IN2015DN03110A (en) | 2012-11-13 | 2015-10-02 | Procter & Gamble | |
| EP2730596A1 (en) | 2012-11-13 | 2014-05-14 | Basf Se | Polyurethane soft foam materials containing plant seeds |
| KR20140063400A (en) * | 2012-11-15 | 2014-05-27 | 주식회사 엘지화학 | Super absorbent polymer |
| JP2015535034A (en) | 2012-11-15 | 2015-12-07 | エルジー・ケム・リミテッド | Method for producing superabsorbent resin |
| EP3896104A1 (en) | 2012-11-21 | 2021-10-20 | Basf Se | Surface-postcrosslinked water-absorbent polymer particles |
| CN104812418B (en) | 2012-11-26 | 2019-02-19 | 巴斯夫欧洲公司 | The method for preparing superabsorbents based on renewable raw materials |
| DE202012013571U1 (en) | 2012-12-10 | 2017-12-06 | The Procter & Gamble Company | Absorbent particles with high absorption material content |
| DE202012013572U1 (en) | 2012-12-10 | 2017-12-05 | The Procter & Gamble Company | Absorbent article with high absorption material content |
| US9216116B2 (en) | 2012-12-10 | 2015-12-22 | The Procter & Gamble Company | Absorbent articles with channels |
| EP2740449B1 (en) | 2012-12-10 | 2019-01-23 | The Procter & Gamble Company | Absorbent article with high absorbent material content |
| PL2740452T3 (en) | 2012-12-10 | 2022-01-31 | The Procter & Gamble Company | Absorbent article with high absorbent material content |
| HUE044699T2 (en) | 2012-12-10 | 2019-11-28 | Procter & Gamble | Absorbent article with profiled acquisition-distribution system |
| US10639215B2 (en) | 2012-12-10 | 2020-05-05 | The Procter & Gamble Company | Absorbent articles with channels and/or pockets |
| US9216118B2 (en) | 2012-12-10 | 2015-12-22 | The Procter & Gamble Company | Absorbent articles with channels and/or pockets |
| EP2740450A1 (en) | 2012-12-10 | 2014-06-11 | The Procter & Gamble Company | Absorbent core with high superabsorbent material content |
| US8979815B2 (en) | 2012-12-10 | 2015-03-17 | The Procter & Gamble Company | Absorbent articles with channels |
| JP2016506981A (en) | 2013-01-29 | 2016-03-07 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Method for producing water-absorbing polymer particles having high permeability of swollen gel bed, fast swelling speed and high centrifugal retention capacity |
| JP6395727B2 (en) | 2013-01-30 | 2018-09-26 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Method for removing residual monomer from water-absorbing polymer particles |
| US9820894B2 (en) | 2013-03-22 | 2017-11-21 | The Procter & Gamble Company | Disposable absorbent articles |
| JP6163254B2 (en) | 2013-04-08 | 2017-07-12 | ザ プロクター アンド ギャンブル カンパニー | Absorbent article with barrier leg cuff |
| US9302248B2 (en) | 2013-04-10 | 2016-04-05 | Evonik Corporation | Particulate superabsorbent polymer composition having improved stability |
| US9375507B2 (en) | 2013-04-10 | 2016-06-28 | Evonik Corporation | Particulate superabsorbent polymer composition having improved stability |
| DE102013208942A1 (en) | 2013-05-15 | 2014-11-20 | Evonik Industries Ag | Superabsorbent polymers with fast absorption properties and process for its preparation |
| FR3005660B1 (en) * | 2013-05-17 | 2015-04-24 | Arkema France | SURFACE CROSSLINKING PROCESS OF POLYMER PARTICLES |
| EP2813201B1 (en) | 2013-06-14 | 2017-11-01 | The Procter and Gamble Company | Absorbent article and absorbent core forming channels when wet |
| CN103360555B (en) * | 2013-07-31 | 2016-01-20 | 苏州大学 | Super absorbent resin of a kind of high rate of liquid aspiration and preparation method thereof |
| US9950308B2 (en) | 2013-08-01 | 2018-04-24 | Lg Chem, Ltd. | Superabsorbent polymer |
| JP2016535646A (en) | 2013-08-26 | 2016-11-17 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Fluid absorbent product |
| US10335324B2 (en) | 2013-08-27 | 2019-07-02 | The Procter & Gamble Company | Absorbent articles with channels |
| US9987176B2 (en) | 2013-08-27 | 2018-06-05 | The Procter & Gamble Company | Absorbent articles with channels |
| WO2015036273A1 (en) | 2013-09-12 | 2015-03-19 | Basf Se | Method for producing acrylic acid |
| US11207220B2 (en) | 2013-09-16 | 2021-12-28 | The Procter & Gamble Company | Absorbent articles with channels and signals |
| RU2636366C2 (en) | 2013-09-16 | 2017-11-22 | Дзе Проктер Энд Гэмбл Компани | Absorbing products with channels and indicating elements |
| EP3351225B1 (en) | 2013-09-19 | 2021-12-29 | The Procter & Gamble Company | Absorbent cores having material free areas |
| KR102191077B1 (en) | 2013-10-30 | 2020-12-15 | 바스프 에스이 | Method for producing water-absorbing polymer particles by suspension polymerization |
| WO2015074966A1 (en) | 2013-11-22 | 2015-05-28 | Basf Se | Process for producing water-absorbing polymer particles |
| US9789009B2 (en) | 2013-12-19 | 2017-10-17 | The Procter & Gamble Company | Absorbent articles having channel-forming areas and wetness indicator |
| PL2886092T3 (en) | 2013-12-19 | 2017-03-31 | The Procter And Gamble Company | Absorbent cores having channel-forming areas and c-wrap seals |
| EP2905001B1 (en) | 2014-02-11 | 2017-01-04 | The Procter and Gamble Company | Method and apparatus for making an absorbent structure comprising channels |
| EP2949300B1 (en) | 2014-05-27 | 2017-08-02 | The Procter and Gamble Company | Absorbent core with absorbent material pattern |
| EP2949302B1 (en) | 2014-05-27 | 2018-04-18 | The Procter and Gamble Company | Absorbent core with curved channel-forming areas |
| EP2949301B1 (en) | 2014-05-27 | 2018-04-18 | The Procter and Gamble Company | Absorbent core with curved and straight absorbent material areas |
| ES2643577T3 (en) | 2014-05-27 | 2017-11-23 | The Procter & Gamble Company | Absorbent core with absorbent material design |
| EP2995323B1 (en) | 2014-09-15 | 2019-02-27 | Evonik Degussa GmbH | Amino polycarboxylic acids as processing aids in the production of superabsorbents |
| EP2995322B1 (en) | 2014-09-15 | 2017-03-01 | Evonik Degussa GmbH | Smell adsorbent |
| WO2016050397A1 (en) | 2014-09-30 | 2016-04-07 | Basf Se | Method for producing water-absorbing polymer particles |
| EP3009474B1 (en) | 2014-10-16 | 2017-09-13 | Evonik Degussa GmbH | Method for the production of water soluble polymers |
| KR20160061743A (en) | 2014-11-24 | 2016-06-01 | 주식회사 엘지화학 | Super absorbent polymer and preparation method thereof |
| WO2016135020A1 (en) | 2015-02-24 | 2016-09-01 | Basf Se | Method for the continuous dehydration of 3-hydroxypropionic acid to give acrylic acid |
| RU2017133027A (en) | 2015-03-16 | 2019-04-16 | Дзе Проктер Энд Гэмбл Компани | Rugged Absorbent Products |
| JP2018508292A (en) | 2015-03-16 | 2018-03-29 | ザ プロクター アンド ギャンブル カンパニー | Absorbent article with improved core |
| WO2016162175A1 (en) | 2015-04-07 | 2016-10-13 | Basf Se | Method for the dehydration of 3-hydroxypropanoic acid to form acrylic acid |
| US10835634B2 (en) | 2015-04-07 | 2020-11-17 | Basf Se | Method for the agglomeration of superabsorber particles |
| US10857256B2 (en) | 2015-04-07 | 2020-12-08 | Basf Se | Method for producing super absorber particles |
| KR102597114B1 (en) | 2015-05-08 | 2023-11-01 | 바스프 에스이 | Production method for producing water-absorbing polymer particles and belt dryer |
| CN107592805B (en) | 2015-05-12 | 2021-07-06 | 宝洁公司 | Absorbent article with improved core and backsheet adhesive |
| US10543129B2 (en) | 2015-05-29 | 2020-01-28 | The Procter & Gamble Company | Absorbent articles having channels and wetness indicator |
| US11535689B2 (en) | 2015-06-19 | 2022-12-27 | Nippon Shokubai Co., Ltd. | Poly (meth) acrylic acid (salt)-based particulate water-absorbing agent and production method therefor |
| WO2016207444A1 (en) | 2015-06-26 | 2016-12-29 | Bostik Inc. | New absorbent article comprising an acquisition/distribution layer and process for making it |
| EP3167859B1 (en) | 2015-11-16 | 2020-05-06 | The Procter and Gamble Company | Absorbent cores having material free areas |
| ES2838027T3 (en) | 2015-12-02 | 2021-07-01 | Hartmann Paul Ag | Absorbent article with improved core |
| CN105384884B (en) * | 2015-12-04 | 2018-10-12 | 湖北航天化学技术研究所 | It is a kind of can chemical degradation propellant curing accelerating agent synthetic method |
| EP3205318A1 (en) | 2016-02-11 | 2017-08-16 | The Procter and Gamble Company | Absorbent article with high absorbent capacity |
| KR102075738B1 (en) | 2016-03-11 | 2020-02-10 | 주식회사 엘지화학 | Super absorbent polymer |
| US10881555B2 (en) | 2016-03-30 | 2021-01-05 | Basf Se | Fluid-absorbent article |
| US20170281425A1 (en) | 2016-03-30 | 2017-10-05 | Basf Se | Fluid-absorbent article |
| US10806640B2 (en) | 2016-03-30 | 2020-10-20 | Basf Se | Ultrathin fluid-absorbent article |
| EP3238676B1 (en) | 2016-04-29 | 2019-01-02 | The Procter and Gamble Company | Absorbent core with profiled distribution of absorbent material |
| EP3238678B1 (en) | 2016-04-29 | 2019-02-27 | The Procter and Gamble Company | Absorbent core with transversal folding lines |
| KR102528637B1 (en) | 2016-05-31 | 2023-05-03 | 바스프 에스이 | Manufacturing method of superabsorbent |
| EP3251648A1 (en) | 2016-05-31 | 2017-12-06 | The Procter and Gamble Company | Absorbent article with improved fluid distribution |
| EP3278782A1 (en) | 2016-08-02 | 2018-02-07 | The Procter and Gamble Company | Absorbent article with improved fluid storage |
| US11325990B2 (en) | 2016-08-10 | 2022-05-10 | Basf Se | Method for the production of superabsorbers |
| US20190255514A1 (en) | 2016-10-26 | 2019-08-22 | Basf Se | Method for discharging superabsorbent particles from a silo and filling them into bulk containers |
| US10828208B2 (en) | 2016-11-21 | 2020-11-10 | The Procte & Gamble Company | Low-bulk, close-fitting, high-capacity disposable absorbent pant |
| PL3576701T3 (en) | 2017-02-06 | 2023-03-20 | Basf Se | Fluid-absorbent article |
| EP3582734B1 (en) | 2017-02-17 | 2021-12-01 | Basf Se | Fluid-absorbent article |
| EP3391959A1 (en) | 2017-04-19 | 2018-10-24 | The Procter & Gamble Company | Method for making water-absorbing polymer particles having areas with inorganic solid particles and areas substantially free of inorganic solid particles |
| US11053370B2 (en) | 2017-04-19 | 2021-07-06 | The Procter & Gamble Company | Agglomerated superabsorbent polymer particles having a specific size ratio |
| US10875985B2 (en) | 2017-04-19 | 2020-12-29 | The Procter & Gamble Company | Superabsorbent polymer particles comprising one or more than one area(s) with clay platelets and at least two distinct areas substantially free of clay platelets |
| EP3391961A1 (en) | 2017-04-19 | 2018-10-24 | The Procter & Gamble Company | Agglomerated superabsorbent polymer particles having a specific size ratio |
| EP3391958B1 (en) | 2017-04-19 | 2020-08-12 | The Procter & Gamble Company | Method of making surface-coated water-absorbing polymer particles in a microfluidic device |
| US10767029B2 (en) | 2017-04-19 | 2020-09-08 | The Procter & Gamble Company | Agglomerated superabsorbent polymer particles comprising clay platelets with edge modification and/or surface modification |
| EP3391963B1 (en) | 2017-04-19 | 2021-04-14 | The Procter & Gamble Company | Process to prepare agglomerated superabsorbent polymer particles comprising clay platelets with edge modification and/or surface modification |
| EP3391960B1 (en) | 2017-04-19 | 2023-11-22 | The Procter & Gamble Company | Superabsorbent polymer particles comprising one, or more than one area(s) with clay platelets and at least two distinct, non-adjacent areas with no clay platelets |
| EP3391962A1 (en) | 2017-04-19 | 2018-10-24 | The Procter & Gamble Company | Method for making water-absorbing polymer particles |
| US20180333310A1 (en) | 2017-05-18 | 2018-11-22 | The Procter & Gamble Company | Incontinence pant with low-profile unelasticized zones |
| WO2018233731A1 (en) | 2017-06-21 | 2018-12-27 | Geohumus Gmbh | Water-swellable hybrid material |
| CN110832011B (en) | 2017-07-12 | 2023-03-10 | 巴斯夫欧洲公司 | Method of preparing superabsorbent polymer particles |
| EP3661662A1 (en) | 2017-07-31 | 2020-06-10 | Basf Se | Classification process for superabsorbent polymer particles |
| WO2019076682A1 (en) | 2017-10-18 | 2019-04-25 | Basf Se | Method for the production of superabsorbers |
| DE202017005496U1 (en) | 2017-10-24 | 2017-12-19 | The Procter & Gamble Company | disposable diaper |
| CN111278551B (en) | 2017-11-10 | 2023-09-29 | 巴斯夫欧洲公司 | Super absorbent |
| DE202017006016U1 (en) | 2017-11-21 | 2017-12-01 | The Procter & Gamble Company | Absorbent article with channels |
| DE202017006014U1 (en) | 2017-11-21 | 2018-01-14 | The Procter & Gamble Company | Absorbent article with pockets |
| JP2019094444A (en) * | 2017-11-24 | 2019-06-20 | Ｓｄｐグローバル株式会社 | Water-absorbable resin particle and production method thereof |
| US11491463B2 (en) | 2018-01-09 | 2022-11-08 | Basf Se | Superabsorber mixtures |
| SG11202006619UA (en) * | 2018-01-18 | 2020-08-28 | Sumitomo Seika Chemicals | Water-absorbent resin |
| KR20200118002A (en) | 2018-02-06 | 2020-10-14 | 바스프 에스이 | Pneumatic transport method of super absorbent particles |
| KR20200125931A (en) | 2018-02-22 | 2020-11-05 | 바스프 에스이 | Method for producing super absorbent particles |
| EP3774999B1 (en) | 2018-04-10 | 2022-08-03 | Basf Se | Permeable superabsorber and method for the production thereof |
| US20220071818A9 (en) | 2018-04-20 | 2022-03-10 | Basf Se | Thin fluid absorbent core-absorbent paper |
| JP7362653B2 (en) | 2018-04-20 | 2023-10-17 | ビーエーエスエフ ソシエタス・ヨーロピア | How to make superabsorbents |
| KR20210035807A (en) | 2018-07-24 | 2021-04-01 | 바스프 에스이 | Method of manufacturing super absorbent |
| JP2021532865A (en) | 2018-08-01 | 2021-12-02 | ビーエイエスエフ・ソシエタス・エウロパエアBasf Se | Fluid absorbent core |
| CN112638337B (en) | 2018-08-01 | 2023-01-20 | 巴斯夫欧洲公司 | Feminine hygiene absorbent article |
| JP7450603B2 (en) | 2018-08-20 | 2024-03-15 | ベーアーエスエフ・エスエー | Superabsorbent manufacturing method |
| JP2022502543A (en) | 2018-09-28 | 2022-01-11 | ビーエーエスエフ ソシエタス・ヨーロピアBasf Se | Method of manufacturing superabsorbent |
| US20210354108A1 (en) | 2018-10-29 | 2021-11-18 | Basf Se | Process for producing long-term color stable superabsorbent polymer particles |
| DE102019216910A1 (en) | 2018-11-12 | 2020-05-14 | Basf Se | Process for post-crosslinking superabsorbents |
| JP2022507247A (en) | 2018-11-14 | 2022-01-18 | ビーエーエスエフ ソシエタス・ヨーロピア | How to make a superabsorbent |
| WO2020099153A1 (en) | 2018-11-14 | 2020-05-22 | Basf Se | Process for producing superabsorbents |
| CN112996592A (en) | 2018-11-14 | 2021-06-18 | 巴斯夫欧洲公司 | Process for producing superabsorbers |
| JP7446659B2 (en) | 2018-11-29 | 2024-03-11 | ベーアーエスエフ・エスエー | Prediction of physical properties of superabsorbent polymers |
| JP2022523660A (en) | 2019-01-23 | 2022-04-26 | ビーエーエスエフ ソシエタス・ヨーロピア | How to make superabsorbent particles |
| WO2020151971A1 (en) | 2019-01-23 | 2020-07-30 | Basf Se | Method for producing superabsorbent particles |
| WO2020151969A1 (en) | 2019-01-23 | 2020-07-30 | Basf Se | Method for producing superabsorbent particles |
| WO2020151972A1 (en) | 2019-01-23 | 2020-07-30 | Basf Se | Method for producing super absorbent particles |
| WO2020151970A1 (en) | 2019-01-24 | 2020-07-30 | Basf Se | Method for producing superabsorbent particles |
| KR20210135256A (en) | 2019-03-01 | 2021-11-12 | 바스프 에스이 | Method for manufacturing superabsorbent polymer particles |
| WO2021013639A1 (en) | 2019-07-24 | 2021-01-28 | Basf Se | Permeable superabsorbent and process for production thereof |
| RU2729652C1 (en) * | 2019-12-30 | 2020-08-11 | Общество с ограниченной ответственностью "НефтеПром Сервис" | Oil formation development method |
| WO2022058190A1 (en) | 2020-09-17 | 2022-03-24 | Basf Se | Process for producing superabsorbent polymer particles |
| CN114426326B (en) * | 2020-09-21 | 2023-04-18 | 中国石油化工股份有限公司 | Oily sewage treatment flocculant and preparation method and application thereof |
| EP4237386A1 (en) | 2020-10-28 | 2023-09-06 | The Procter & Gamble Company | Cementitious compositions comprising recycled superabsorbent polymer |
| JP2024503203A (en) | 2020-12-16 | 2024-01-25 | ベーアーエスエフ・エスエー | Process for producing superabsorber particles |
| WO2023046583A1 (en) | 2021-09-27 | 2023-03-30 | Basf Se | Process for producing superabsorbent particles |
| WO2023168616A1 (en) | 2022-03-09 | 2023-09-14 | The Procter & Gamble Company | Absorbent article with high permeability sap |
| US20240091073A1 (en) | 2022-09-08 | 2024-03-21 | The Procter & Gamble Company | Disposable absorbent pants with elasticized waist panel structure and obscuring print patterns |
Family Cites Families (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT22915B (en) * | 1903-02-21 | 1906-02-10 | United Shoe Machinery Ab | Last carrier for take-up machines. |
| DE2706135C2 (en) * | 1977-02-14 | 1982-10-28 | Chemische Fabrik Stockhausen GmbH, 4150 Krefeld | Thickener for excreted intestinal contents and urine |
| DE3141098A1 (en) * | 1981-10-16 | 1983-04-28 | Chemische Fabrik Stockhausen GmbH, 4150 Krefeld | ABSORPTION MATERIAL FOR WATER, AQUEOUS SOLUTIONS AND AQUEOUS BODY LIQUIDS |
| JPS63210102A (en) * | 1987-02-27 | 1988-08-31 | Mitsubishi Petrochem Co Ltd | Manufacture of highly water-absorptive polymer |
| DE3713601A1 (en) * | 1987-04-23 | 1988-11-10 | Stockhausen Chem Fab Gmbh | METHOD FOR PRODUCING A STRONG WATER-ABSORBENT POLYMER |
| GB8800578D0 (en) * | 1988-01-12 | 1988-02-10 | Fernandes P J F | Improvements relating to plant growth media |
| US5408019A (en) * | 1990-05-11 | 1995-04-18 | Chemische Fabrik Stockhausen Gmbh | Cross-linked, water-absorbing polymer and its use in the production of hygiene items |
| JP3119900B2 (en) * | 1991-07-11 | 2000-12-25 | 三菱化学株式会社 | Method for producing superabsorbent polymer |
| DE4221381C1 (en) * | 1992-07-02 | 1994-02-10 | Stockhausen Chem Fab Gmbh | Graft copolymers of unsaturated monomers and sugars, process for their preparation and their use |
| DE9201764U1 (en) * | 1992-02-12 | 1992-04-09 | Fabritz, Gerhard, 4150 Krefeld, De | |
| DE69312126T2 (en) * | 1992-03-05 | 1997-11-06 | Nippon Catalytic Chem Ind | Process for producing an absorbent resin |
| GB9208449D0 (en) * | 1992-04-16 | 1992-06-03 | Dow Deutschland Inc | Crosslinked hydrophilic resins and method of preparation |
| DE4244548C2 (en) * | 1992-12-30 | 1997-10-02 | Stockhausen Chem Fab Gmbh | Powdery liquids under load as well as blood-absorbing polymers, processes for their production and their use in textile constructions for personal hygiene |
| DE69412547T2 (en) * | 1993-06-18 | 1999-04-22 | Nippon Catalytic Chem Ind | Process for the production of an absorbent resin |
| US5314420A (en) * | 1993-09-17 | 1994-05-24 | Nalco Chemical Company | Superabsorbent polymer having improved absorption rate and absorption under pressure |
| DE4333056C2 (en) * | 1993-09-29 | 1998-07-02 | Stockhausen Chem Fab Gmbh | Powdery, aqueous liquid-absorbing polymers, processes for their preparation and their use as absorbents |
| DE4344224A1 (en) * | 1993-12-23 | 1995-06-29 | Stockhausen Chem Fab Gmbh | Crosslinked synthetic polymers with porous structure, high absorption rate for water, aqueous solutions and body fluids, a process for their preparation and their use for the absorption and / or retention of water and / or aqueous liquids |
| DE19504529A1 (en) * | 1995-02-11 | 1996-08-14 | Huels Chemische Werke Ag | Process for the production of gas permeable, liquid absorbing and storing agglomerates |
-
1996
- 1996-11-11 DE DE19646484A patent/DE19646484C2/en not_active Expired - Fee Related
- 1996-11-18 BR BR9611469A patent/BR9611469A/en not_active IP Right Cessation
- 1996-11-18 TR TR1998/00900T patent/TR199800900T2/en unknown
- 1996-11-18 DE DE59602822T patent/DE59602822D1/en not_active Expired - Lifetime
- 1996-11-18 CA CA002236504A patent/CA2236504A1/en not_active Abandoned
- 1996-11-18 JP JP51937997A patent/JP4001350B2/en not_active Expired - Lifetime
- 1996-11-18 RU RU98111755/04A patent/RU2193045C2/en active
- 1996-11-18 PL PL96326840A patent/PL326840A1/en unknown
- 1996-11-18 WO PCT/EP1996/005075 patent/WO1997019116A1/en active IP Right Grant
- 1996-11-18 CN CN96199633A patent/CN1106415C/en not_active Expired - Lifetime
- 1996-11-18 AU AU76273/96A patent/AU718132B2/en not_active Ceased
- 1996-11-18 EP EP96939094A patent/EP0862590B1/en not_active Expired - Lifetime
- 1996-11-18 KR KR19980703803A patent/KR100444022B1/en not_active IP Right Cessation
- 1996-11-18 AT AT96939094T patent/ATE183526T1/en not_active IP Right Cessation
- 1996-11-18 MX MX9803991A patent/MX202050B/en unknown
- 1996-11-18 ES ES96939094T patent/ES2138385T3/en not_active Expired - Lifetime
- 1996-11-19 TW TW085114159A patent/TW438821B/en not_active IP Right Cessation
- 1996-11-20 US US08/752,889 patent/US5837789A/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8383746B2 (en) | 2006-03-27 | 2013-02-26 | Nippon Shokubai Co., Ltd | Water absorbing resin with improved internal structure and manufacturing method therefor |
Also Published As
| Publication number | Publication date |
|---|---|
| AU718132B2 (en) | 2000-04-06 |
| WO1997019116A1 (en) | 1997-05-29 |
| KR19990071530A (en) | 1999-09-27 |
| BR9611469A (en) | 1999-06-15 |
| ATE183526T1 (en) | 1999-09-15 |
| ES2138385T3 (en) | 2000-01-01 |
| MX202050B (en) | 2001-05-25 |
| JP2002515079A (en) | 2002-05-21 |
| RU2193045C2 (en) | 2002-11-20 |
| JP4001350B2 (en) | 2007-10-31 |
| US5837789A (en) | 1998-11-17 |
| TW438821B (en) | 2001-06-07 |
| PL326840A1 (en) | 1998-10-26 |
| TR199800900T2 (en) | 1999-12-21 |
| AU7627396A (en) | 1997-06-11 |
| DE19646484C2 (en) | 2000-10-19 |
| MX9803991A (en) | 1998-09-30 |
| DE19646484A1 (en) | 1997-05-22 |
| KR100444022B1 (en) | 2004-11-03 |
| EP0862590B1 (en) | 1999-08-18 |
| EP0862590A1 (en) | 1998-09-09 |
| CN1106415C (en) | 2003-04-23 |
| DE59602822D1 (en) | 1999-09-23 |
| CN1207745A (en) | 1999-02-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2236504A1 (en) | Fluid-absorbing polymers, process for the preparation and use thereof | |
| US6087450A (en) | Water-swelling polymers cross-linked with unsaturated amino alcohols, the production and use of same | |
| JP3941880B2 (en) | Absorbents for water and aqueous liquids, and production methods and uses thereof | |
| US6143821A (en) | Water-absorbing polymers with improved properties, process for the preparation and use thereof | |
| US4076663A (en) | Water absorbing starch resins | |
| US6911499B1 (en) | Polymer composition and a method for producing the same | |
| RU2139096C1 (en) | Powdered cross-linked polymers absorbing loaded aqueous liquids and blood, method of preparing such polymers, and body hygiene-destined textile structures | |
| CA2171085C (en) | Powder-form polymers capable of absorbing aqueous liquids, method of preparing them and their use as absorbents | |
| US5532323A (en) | Method for production of absorbent resin | |
| EP1196204B1 (en) | Superabsorbent polymers having delayed water absorption characteristics | |
| US20140339469A1 (en) | Biodegradable superabsorbent polymer composition with good absorption and retention properties | |
| MXPA01007454A (en) | HIGHLY DILATABLE HYDROGELS, HYDROPHILIC, RETICULATED, METHOD FOR PRODUCTION AND USE | |
| US20050245684A1 (en) | Water absorbing agent and method for the production thereof | |
| JP2003511489A (en) | Mechanically stable hydrogel-forming polymers | |
| EP1244474A1 (en) | High permeability, low absorption capacity polymers | |
| JPH08510484A (en) | Water-absorbent resin particles of crosslinked carboxyl-containing polymer and method for producing the same | |
| JPH069717A (en) | Production of water-absorbent resin | |
| WO2002032975A1 (en) | Hydrogel-forming polymers |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued |