CA2116381C - Zero slump - loss superplasticizer - Google Patents
Zero slump - loss superplasticizer Download PDFInfo
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- CA2116381C CA2116381C CA002116381A CA2116381A CA2116381C CA 2116381 C CA2116381 C CA 2116381C CA 002116381 A CA002116381 A CA 002116381A CA 2116381 A CA2116381 A CA 2116381A CA 2116381 C CA2116381 C CA 2116381C
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
- C04B24/24—Macromolecular compounds
- C04B24/26—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
- C04B24/2641—Polyacrylates; Polymethacrylates
- C04B24/2647—Polyacrylates; Polymethacrylates containing polyether side chains
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
- C04B24/24—Macromolecular compounds
- C04B24/26—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
- C04B24/2688—Copolymers containing at least three different monomers
- C04B24/2694—Copolymers containing at least three different monomers containing polyether side chains
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
- C04B24/24—Macromolecular compounds
- C04B24/28—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
- C04B24/32—Polyethers, e.g. alkylphenol polyglycolether
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
- C04B28/06—Aluminous cements
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/0045—Polymers chosen for their physico-chemical characteristics
- C04B2103/0061—Block (co-)polymers
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/30—Water reducers, plasticisers, air-entrainers, flow improvers
- C04B2103/308—Slump-loss preventing agents
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/30—Water reducers, plasticisers, air-entrainers, flow improvers
- C04B2103/32—Superplasticisers
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- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Macromonomer-Based Addition Polymer (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Developing Agents For Electrophotography (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
A superplasticizing additive for concrete and other cementitious mixes with high retention of workability (low "slump loss") and low air-entraining effect, is made by terpolymers of a) (meth)acrylic acid and its salts, b)polyethyleneglycolmonomethylether-(meth)acrylate and c) polypropyleneglycol-di(meth)acrylate.
Description
'ZERO SLURP - LOSS SOPBRPLASTICIZER' 211~3~1 1. BRIEF DESCRIPTION OF THE INVENTION
The present invention relates to a new superplasticizing additive for concrete and other cementitious materials capable to considerably increase the initial workability of the mixes and to maintain this workability for longer periods than those corresponding to the traditional superplasticizers and to allow an easy placing of the concrete. More particularly, the present invention relates to a superplasticizer with the above mentioned properties and further characterized by a low air-entraining effect and no adverse effect on the mechanical properties of the concrete, even at the early age of curing.
The present invention relates to a new superplasticizing additive for concrete and other cementitious materials capable to considerably increase the initial workability of the mixes and to maintain this workability for longer periods than those corresponding to the traditional superplasticizers and to allow an easy placing of the concrete. More particularly, the present invention relates to a superplasticizer with the above mentioned properties and further characterized by a low air-entraining effect and no adverse effect on the mechanical properties of the concrete, even at the early age of curing.
2. DESCRIPTION OF THE STATE-OF-ART
Superplasticizers are extensively used in the construction industry because their addition considerably increases the fluidity of fresh concrete without adding more water to the mix. Furthermore, they allow a considerable reduction of the mixing water and an easy placing of high quality concretes which, once hardened, are characterized by high strength.
Traditional superplasticizers based on the condensation between formaldehyde and naphthalene sulfonic acid salts Z
(NSFC) or melamine sulphite modified resins (MSFC) cannot maintain the workability of fresh mixes for long periods. So, even after few minutes, a sharp decrease of the fluidity can occur, known as "slump-loss" effect of the fresh concrete.
When "slump-loss" occurs, the initial workability is normally restored at the site of placing by adding more water to the mix, with a consequent adverse effect on the mechanigal properties and the durability of the hardened concrete.
Recently, "zero slump-loss" superplasticizers have been I
developed capable to maintain the same fluidity for longer periods and allow the transport of fresh concrete for long distances without further retempering the concrete at the placing-site. These new additives are based on crosslinked hydrophilic acrylic polymers which hydrolize in the strong alkaline medium of cementitious mixes to produce linear polymer chains which reduce the "slump loss" effect.
Examples of such additives are described in Japanese Patent Application No. 02 281014, based on copolymers of (meth)acrylic acid, ethoxy esters of (meth)acrylic acid and a crosslinking monomer having the following general formula:
X X
CH2 = C - C - Y - C - C = CH2 (I) where:
X represents hydrogen or methyl radical;
Superplasticizers are extensively used in the construction industry because their addition considerably increases the fluidity of fresh concrete without adding more water to the mix. Furthermore, they allow a considerable reduction of the mixing water and an easy placing of high quality concretes which, once hardened, are characterized by high strength.
Traditional superplasticizers based on the condensation between formaldehyde and naphthalene sulfonic acid salts Z
(NSFC) or melamine sulphite modified resins (MSFC) cannot maintain the workability of fresh mixes for long periods. So, even after few minutes, a sharp decrease of the fluidity can occur, known as "slump-loss" effect of the fresh concrete.
When "slump-loss" occurs, the initial workability is normally restored at the site of placing by adding more water to the mix, with a consequent adverse effect on the mechanigal properties and the durability of the hardened concrete.
Recently, "zero slump-loss" superplasticizers have been I
developed capable to maintain the same fluidity for longer periods and allow the transport of fresh concrete for long distances without further retempering the concrete at the placing-site. These new additives are based on crosslinked hydrophilic acrylic polymers which hydrolize in the strong alkaline medium of cementitious mixes to produce linear polymer chains which reduce the "slump loss" effect.
Examples of such additives are described in Japanese Patent Application No. 02 281014, based on copolymers of (meth)acrylic acid, ethoxy esters of (meth)acrylic acid and a crosslinking monomer having the following general formula:
X X
CH2 = C - C - Y - C - C = CH2 (I) where:
X represents hydrogen or methyl radical;
Y represents -O-(R1-)n-O- radical (R1 is an alkylene radical and n is integer from 2 to 30). In this case the crosslinking agents of formula (I) can be obtained by reacting (meth)acrylic acid and ethylene glycol (R1= CH2, n=2) or superior glycols (1,4-butanediol, 1,6-exanediol, 1,8 octanediol, etc. for n>2). Alternatively, Y may be a -O-(R2a-0-R2b-) n-O radical (with R2a and R2b C2-C5 alkylene radicals and n integer from 2 to 30).
In this case, the crosslinking agents of formula (I) can be obtained by reacting (meth)acrylic acid and polyglycol ethers having alkylene radicals with at least 4 carbon atoms, according to the formula -(-0-R2b-R2a-0-R2b-R2a-0-) Examples of such compounds are those obtained by reacting (meth)acrylic acid and poly-tetramethyleneglycols (PTMEG) having general formula HO-(CH2CH2CH2CH20)n-H. Other crosslinking agents reported in Japanese Patent Application n. 281014 are ethylene-glycol-di(meth)acrylate (EG-DA), diethylene glycol di(meth)acrylate (2EG-DA) Triethylene glycol di (meth)acrylate (3EG-DA), 4-ethylene glycol di(meth)acrylate (5EG-DA), 9-ethylene glycol di(meth)acrylate (9EG-DA), 14-ethylene glycol di(meth)acrylate and their combination.
European Patent Application n. 448717A1 describes other crosslinking agents for the production of superplasticizers having low "slump-loss" effect. Such crosslinking agents are represented by the following formulas containing epoxy groups:
In this case, the crosslinking agents of formula (I) can be obtained by reacting (meth)acrylic acid and polyglycol ethers having alkylene radicals with at least 4 carbon atoms, according to the formula -(-0-R2b-R2a-0-R2b-R2a-0-) Examples of such compounds are those obtained by reacting (meth)acrylic acid and poly-tetramethyleneglycols (PTMEG) having general formula HO-(CH2CH2CH2CH20)n-H. Other crosslinking agents reported in Japanese Patent Application n. 281014 are ethylene-glycol-di(meth)acrylate (EG-DA), diethylene glycol di(meth)acrylate (2EG-DA) Triethylene glycol di (meth)acrylate (3EG-DA), 4-ethylene glycol di(meth)acrylate (5EG-DA), 9-ethylene glycol di(meth)acrylate (9EG-DA), 14-ethylene glycol di(meth)acrylate and their combination.
European Patent Application n. 448717A1 describes other crosslinking agents for the production of superplasticizers having low "slump-loss" effect. Such crosslinking agents are represented by the following formulas containing epoxy groups:
n n ~~-cx2-o-c- (cx2 ) ~-cH2-cx~cx- (a~ ) 6-c-o-~2-c\ ~ 2 0 Qi-CEi2 0 -CH-~CH2-0-C- (Qi2 ) 6-~i~- (Qi2 ) ~..~-~2-CH-f~i2 ' \0/ \0 \ 2 ~ i'C~i2-O"C- O -O-CH2"~~2 10. Qi2-(~i-~H2-0-C- (CH2 ) 5-Qi (C~i2 ) ~-C-4-Qi2~.1 0 C~32-(~3 . 0 ~2-(~i-C~i2-O-C- ( c~i2 ) ~- ( CH2 ) 9-C-O-(~i2-~i2 0 CH2-L~i3 15' 0 0 -C~i-L~i2-,O-CI- ( C~i2 ) 6-L~id~i- ( CH2 ) 2-~H~i- ( Qi2 ) 6-C-0-t'~i2-C.H-C~i2 2 0.
or by unsaturated monomers obtained by such epoxy compounds.
A noteworthy drawback of this type of superplasticizers is the air-entraining effect they produce in the cement mixes, as already pointed out by V.S. Ramachandran (9th 25 International Congress on the Chemistry of Cement, Vol.l, pp.
529-568, 1992, New Delhi). This effect, besides causing a 211b381 strength decrease, also affects the appearance of the concrete.
Just to reduce the air-entraining effect caused by these superplasticizers, European Patent Application n. 448717A1 recommends the use of highly hydrophilic monomers such as:
CH2 = C - COO - (R50-)m - R6 - S03M (II) where:
R3 is H or -CH3;
R5 and R6 independently represent alkylene radicals containing from 2 to 4 carbon atoms.
Examples of such type of monomers (II) are, for example, 2-sulfoethyl(meth)acrylate, 2-sulfopropyl (meth)-acrylate, sulfoethoxypolyethylenglycol(meth)acrylate, sulfoethoxypolypropylenglycolmono(meth)acrylate, etc. and their salts.
In order to reduce the air-entraining effect of this type of polymers, in European Patent Application n. 0331308, is recommended the use of considerable amount (from 5 to 15 per cent by weight of the monomers) of the following monomer:
CH2 = C - CH2 - S03M (III) where:
R2 is H or CH3 3. DETAILED DESCRIPTION OF THE PRESENT INVENTION
The present invention relates to new crosslinked water soluble or water-dispersible acrylic polymers, which can find application as "zero slump-loss" superplasticizers, ha-wing different structures than those reported in the afore-mentioned patent applications.
Furthermore, the new additives of the present invention are characterized by a very low air-entraining effect, even in the absence of monomers of formulas (II) and (III), till now considered essential to produce superplasticizers with a low air-entraining effect.
The new crosslinked superplasticizers object of the pre-sent invention are obtained by terpolymerization of the fol-lowing monomers (IV), (V), (VI):
X
CH2 = C - C - O - Z (IV) O
where Z= H, Na, R, Li, 1/2 Ca and X is H or CH3, examples of such monomers are acrylic acid, methacrylic acid and their salts;
X
CH2 = C - C - O - W (V) O
where W= -(-CH2-CH2-0-)n-CH3, n is integer from 2 to 50 and X is H or CH3; these monomers comprise polyethyleneglycols-2I.~~~B~
monomethylether-(meth)acrylate .with molecular weight from 200 to 2000; and X X
CH2 = C - C - O - Y - C - C = CH2 ( VI ) O O
I
where Y - -(CH-CH2-0)m- and m is an integer from 2 to 50.
These monomers are preferably represented by polypropylene-glycol-di-(meth)acrylate with molecular weight of approxima-tely between 280 and 3100, i.e. with m approximately between 2 and 50.
The main difference among the polymer of the present in-vention and those described in the aforementioned patent ap-plications is the crosslinking agent. In fact, it has been surprisingly found that, in order to obtain "zero slump-loss" superplasticizers with low air-entraining effect, mo-nomers having formula (VI) are necessary, in which Y repre-sents propyloxy group CH3 -(CH-CH2-O)m and m is an integer from 5 to 50. The monomers of the pre-sent invention are substantially different from those de-scribed in the previous patent applications, in which the special sulfonated monomer units reported in formulas II and III are essential to reduce the air entraining effect.
The acrylic crosslinked polymers of the present invention may be obtained by terpolymerizing, in different ratios, the monomers of the formulas (IV), (V), (VI). Even though many combinations are possible, it has been observed that the best results, in terms of loss of workability ("slump-loss") and air- entraining effect, are obtained when the amount of acrylic monomers (IV) and (V) is from 90 to 99.9 per cent of the polymerizable mass and the amount of monomer (VI) is from 0.1 to 10 per cent of the polymerizable mass.
The polymers of the present invention can be conveniently synthetized by many of the polymerisation methods known in the art. In the following examples, some preparations of polymers of the present invention are described.
Example 1 648 g of water are charged in a glass bottom-rounded reactor equipped with mechanical stirrer, thermometer and reflux condenser. The system is purged with nitrogen and heated at 90 °C. After the addition of 6.3 g of potassium persulfate K2S2O8, a mixture of 28 g of methacrylic acid, 247 g of polyethyleneglycolmonomethylether methacrylate of molecular weight 818 and 7 g of polypropyleneglycoldimethacrylate of molecular weight 861 is added in one hour. The system is further kept at 90 °C for one hour and then neutralized with 60 g of a 30 per cent solution of NaOH. About 990 g of an amber-coloured polymer solution are obtained, having a total solids content of 30 per cent and a viscosity of about 300 cps at 20 °C.
21163~~
Example 2 648 g of water are charged in a glass bottom-rounded reactor equipped with mechanical stirrer, thermometer and reflux condenser. The system is purged with nitrogen and heated at 90 °C. After the addition of 6.3 g of potassium persulfate K2S20g, a mixture of 30 g of methacrylic acid, 251 g of polyethyleneglycolmonomethylether methacrylate of molecular weight 818 and 1 g of polypropyleneglycoldimethacrylate of molecular weight 861 is added in one hour. The system is further kept at 90 °C for one hour and then neutralized with 60 g of a 30 per cent solution of NaOH. About 990 g of an amber-coloured polymer solution are obtained, having a total solids content of 30 per cent and a viscosity of about 250 cps at 20 °C.
Example 3 648 g of water are charged in a glass bottom-rounded reactor equipped with mechanical stirrer, thermometer and reflux condenser. The system is purged with nitrogen and heated at 90 °C. After the addition of 6.3 g of potassium persulfate K2S20g, a mixture of 25 g of methacrylic acid, 229 g of polyethyleneglycolmonomethylether methacrylate of molecular weight 818 and 28 g of polypropyleneglycoldimethacrylate of molecular weight 861 is added in one hour. The system is further kept at 90 °C for one hour and then neutralized with 60 g of a 30 per cent solution of NaOH. About 990 g of an amber-coloured polymer solution are obtained, having a total solids content of 30 per cent and a viscosity of about 400 cps at 20 °C.
Example 4 This example describes a polymer synthetized using a crosslinking agent (14-ethyleneglycoldimethacrylate) selected among those indicated in the Japanese Patent Application n.
281014. The polymer so obtained has been used in concrete tests in comparison with the polymers of the present invention.
648 g of water are charged in a glass bottom-rounded reactor equipped with mechanical stirrer, thermometer and reflux condenser. The system is purged with nitrogen and heated at 90 °C. After the addition of 6.3 g of potassium persulfate K2S2Og, a mixture of 28 g of methacrylic acid, 247 g of polyethyleneglycolmonomethylether methacrylate of molecular weight 818 and 7 g of polyethyleneglycoldimethacrylate of average molecular weight 770 (14EG-DMA) is added in one hour. The system is further kept at 90 °C for one hour and then neutralized with 60 g of 2fl a 30 per cent solution of NaOH. About 990 g of an amber-coloured polymer solution are obtained, having a total solids content of 30 per cent and a viscosity of about 350 cps at 20°C.
Example 5 This example reports the results of concrete tests made using the polymers of the present invention (Examples 1, 2 and 3) as superplasticizer in comparison both to a traditional superplasticizer based on naphthalene sulfonated formaldehyde condensate (NSFC) and a polymer synthetized using 14- ethyleneglycoldimethacrylate as crosslinking agent (14 EG-DMA) selected among those described in the Japanese Patent Application n. 281014 (Example 4). All the concretes were prepared with the same water/cement and aggregate/cement ratios, using Type I Portland cement (400 kg/mc) and coarse aggregate with maximum diameter of 20 mm. The comparative results of the concrete tests are reported in the following table.
Table 1. Comparative concrete tests using the additive of the present invention (Example 1, Example 2, Example 3) and a traditional superplasticizer based on naphthalene sulfonated formaldehyde condensate (NSFC) and a polymer obtained by using the crosslinking agents described in the Japanese Patent Application n. 281014 (Example 4).
Type of cement: Portland Type I.
Dosage of cement: 400 kg/cubic meter.
Coarse aggregate maximum diameter: 20 mm.
Water/cement ratio: 0.42.
Dosage of the different additives:
- Example 1: 0.25% active matter by weight of cement;
- Example 2: 0.25% active matter by weight of cement;
- Example 3: 0.25% active matter by weight of cement;
- Example 4: 0.25% active matter by weight of cement;
- NSFC . 0.50% active matter by weight of cement.
TYPE OF AIR SLUMP COMPRESSIVE
ADDITIVE CONTENT (mm) MECHANICAL
STRENGTH
(MPa) (%) after after after after 1 7 28 mixin 15 min 30 45 min da days da min s EXAMPLE 2.1 240 220 220 185 21 37 48 EXAMPLE 3.0 230 220 210 180 18 35 46 EXAMPLE 1.9 170 150 140 135 22 37 50 EXAMPLE 6.5 240 225 210 185 16 33 44 NSFC 2.1 180 120 80 60 22 38 47 The results of concrete tests of Table 1 clearly indicate that the fluidifying effect of the crosslinked polymer of the present invention (Examples 1, 2, 3) is much higher than that of the commercial additive based on naphthalene sulfonate (NSFC). In fact, the initial value of the fluidity of the concrete mixes (measured by "slump" test) containing the polymers of the present invention, even though at a dosage 50% less than NSFC, is higher or, at least comparable, with the mix containing NSFC.
Furthermore, the crosslinked acrylic polymer of the present invention (Examples 1, 2, 3) shows an excellent retention of the workability (very low "slump-loss"). So, results of Table 1 indicate that, even 45 minutes after the mixing, the concrete mixes additivated with the polymers of the present invention retain 80 per cent of the initial i3 2116381 "slump" value, while the "slump" of the concrete mix containing NSFC drops at 50 per cent of its initial value.
Also the air-entraining effect of the polymers of the present invention (Examples 1, 2, 3) is surprisingly low in comparison to the polymer of Example 4, which has been synthetized using polyethyleneglycoldimethacrylate (14EG-DMA) as crosslinking agent, as reported in Japanese Patent Application n. 281014.
Therefore, the crosslinking agent of the present invention, based on polypropyleneglycoldi(meth)acrylate, allows preparing cementitious mixes with a low air content without requiring the monomers described in the European Patent Applications n. 448717A and n. 0331308, which up to now were belived necessary in order to produce polymer superplasticizers characterized by a low air- entraining effect.
Example 6 In this example the polymer of the present invention has been evaluated as superplasticizer for High Alumina cement 2p based mortars. It is common knowledge that traditional superplasticizers like NSFC (Naphthalene Sulfonated Formaldehyde Condensate and MSFC (Melamine Sulfite Formaldehyde Condensate) do not exert significant fluidifying effect on High Alumina cement. The results of this example (see Table 2) surprisingly show that the polymer of the present invention, even at an exceptionally low dosage, exerts an excellent superplasticizing effect and retain the workability of the mixes based on High Alumina cement and do not cause any decrease in the strength developments.
Table 2. Comparative mortar tests using the additive of the present invention (Example 1, Example 2, Example 3) and a traditional superplasticizer based on naphthalene sulfonated formaldehyde condensate (NSFC).
Type of cement: High Alumina cement (Ciment Fondu, Lafarge) Sand/Cement ratio: 2.0 Water/Cement ratio: 0.30 Dosage of the different additives:
- Example 1: 0.1% active matter by weight of cement - Example 2: 0.1% active matter by weight of cement - Example 3: 0.1% active matter by weight of cement - NSFC . 0.5% active matter by weight of cement TYPE OF AIR FLUIDITY COMPRESSIVE
ADDITIVE CONTENT (%) MECHANICAL
(flow STRENGTH
table (MPa) measurement) (%) after after after after 1 7 28 mixing 15 min 30 min 45 min day days days PLAIN 4.8 15 15 12 10 78 102 111 EXAMPLE 5.0 140 140 130 125 81 100 110 EXAMPLE 4.9 135 135 130 120 80 99 105 EXAMPLE 5.0 132 130 125 118 82 102 109 NSFC 6.5 25 15 15 15 78 102 112
or by unsaturated monomers obtained by such epoxy compounds.
A noteworthy drawback of this type of superplasticizers is the air-entraining effect they produce in the cement mixes, as already pointed out by V.S. Ramachandran (9th 25 International Congress on the Chemistry of Cement, Vol.l, pp.
529-568, 1992, New Delhi). This effect, besides causing a 211b381 strength decrease, also affects the appearance of the concrete.
Just to reduce the air-entraining effect caused by these superplasticizers, European Patent Application n. 448717A1 recommends the use of highly hydrophilic monomers such as:
CH2 = C - COO - (R50-)m - R6 - S03M (II) where:
R3 is H or -CH3;
R5 and R6 independently represent alkylene radicals containing from 2 to 4 carbon atoms.
Examples of such type of monomers (II) are, for example, 2-sulfoethyl(meth)acrylate, 2-sulfopropyl (meth)-acrylate, sulfoethoxypolyethylenglycol(meth)acrylate, sulfoethoxypolypropylenglycolmono(meth)acrylate, etc. and their salts.
In order to reduce the air-entraining effect of this type of polymers, in European Patent Application n. 0331308, is recommended the use of considerable amount (from 5 to 15 per cent by weight of the monomers) of the following monomer:
CH2 = C - CH2 - S03M (III) where:
R2 is H or CH3 3. DETAILED DESCRIPTION OF THE PRESENT INVENTION
The present invention relates to new crosslinked water soluble or water-dispersible acrylic polymers, which can find application as "zero slump-loss" superplasticizers, ha-wing different structures than those reported in the afore-mentioned patent applications.
Furthermore, the new additives of the present invention are characterized by a very low air-entraining effect, even in the absence of monomers of formulas (II) and (III), till now considered essential to produce superplasticizers with a low air-entraining effect.
The new crosslinked superplasticizers object of the pre-sent invention are obtained by terpolymerization of the fol-lowing monomers (IV), (V), (VI):
X
CH2 = C - C - O - Z (IV) O
where Z= H, Na, R, Li, 1/2 Ca and X is H or CH3, examples of such monomers are acrylic acid, methacrylic acid and their salts;
X
CH2 = C - C - O - W (V) O
where W= -(-CH2-CH2-0-)n-CH3, n is integer from 2 to 50 and X is H or CH3; these monomers comprise polyethyleneglycols-2I.~~~B~
monomethylether-(meth)acrylate .with molecular weight from 200 to 2000; and X X
CH2 = C - C - O - Y - C - C = CH2 ( VI ) O O
I
where Y - -(CH-CH2-0)m- and m is an integer from 2 to 50.
These monomers are preferably represented by polypropylene-glycol-di-(meth)acrylate with molecular weight of approxima-tely between 280 and 3100, i.e. with m approximately between 2 and 50.
The main difference among the polymer of the present in-vention and those described in the aforementioned patent ap-plications is the crosslinking agent. In fact, it has been surprisingly found that, in order to obtain "zero slump-loss" superplasticizers with low air-entraining effect, mo-nomers having formula (VI) are necessary, in which Y repre-sents propyloxy group CH3 -(CH-CH2-O)m and m is an integer from 5 to 50. The monomers of the pre-sent invention are substantially different from those de-scribed in the previous patent applications, in which the special sulfonated monomer units reported in formulas II and III are essential to reduce the air entraining effect.
The acrylic crosslinked polymers of the present invention may be obtained by terpolymerizing, in different ratios, the monomers of the formulas (IV), (V), (VI). Even though many combinations are possible, it has been observed that the best results, in terms of loss of workability ("slump-loss") and air- entraining effect, are obtained when the amount of acrylic monomers (IV) and (V) is from 90 to 99.9 per cent of the polymerizable mass and the amount of monomer (VI) is from 0.1 to 10 per cent of the polymerizable mass.
The polymers of the present invention can be conveniently synthetized by many of the polymerisation methods known in the art. In the following examples, some preparations of polymers of the present invention are described.
Example 1 648 g of water are charged in a glass bottom-rounded reactor equipped with mechanical stirrer, thermometer and reflux condenser. The system is purged with nitrogen and heated at 90 °C. After the addition of 6.3 g of potassium persulfate K2S2O8, a mixture of 28 g of methacrylic acid, 247 g of polyethyleneglycolmonomethylether methacrylate of molecular weight 818 and 7 g of polypropyleneglycoldimethacrylate of molecular weight 861 is added in one hour. The system is further kept at 90 °C for one hour and then neutralized with 60 g of a 30 per cent solution of NaOH. About 990 g of an amber-coloured polymer solution are obtained, having a total solids content of 30 per cent and a viscosity of about 300 cps at 20 °C.
21163~~
Example 2 648 g of water are charged in a glass bottom-rounded reactor equipped with mechanical stirrer, thermometer and reflux condenser. The system is purged with nitrogen and heated at 90 °C. After the addition of 6.3 g of potassium persulfate K2S20g, a mixture of 30 g of methacrylic acid, 251 g of polyethyleneglycolmonomethylether methacrylate of molecular weight 818 and 1 g of polypropyleneglycoldimethacrylate of molecular weight 861 is added in one hour. The system is further kept at 90 °C for one hour and then neutralized with 60 g of a 30 per cent solution of NaOH. About 990 g of an amber-coloured polymer solution are obtained, having a total solids content of 30 per cent and a viscosity of about 250 cps at 20 °C.
Example 3 648 g of water are charged in a glass bottom-rounded reactor equipped with mechanical stirrer, thermometer and reflux condenser. The system is purged with nitrogen and heated at 90 °C. After the addition of 6.3 g of potassium persulfate K2S20g, a mixture of 25 g of methacrylic acid, 229 g of polyethyleneglycolmonomethylether methacrylate of molecular weight 818 and 28 g of polypropyleneglycoldimethacrylate of molecular weight 861 is added in one hour. The system is further kept at 90 °C for one hour and then neutralized with 60 g of a 30 per cent solution of NaOH. About 990 g of an amber-coloured polymer solution are obtained, having a total solids content of 30 per cent and a viscosity of about 400 cps at 20 °C.
Example 4 This example describes a polymer synthetized using a crosslinking agent (14-ethyleneglycoldimethacrylate) selected among those indicated in the Japanese Patent Application n.
281014. The polymer so obtained has been used in concrete tests in comparison with the polymers of the present invention.
648 g of water are charged in a glass bottom-rounded reactor equipped with mechanical stirrer, thermometer and reflux condenser. The system is purged with nitrogen and heated at 90 °C. After the addition of 6.3 g of potassium persulfate K2S2Og, a mixture of 28 g of methacrylic acid, 247 g of polyethyleneglycolmonomethylether methacrylate of molecular weight 818 and 7 g of polyethyleneglycoldimethacrylate of average molecular weight 770 (14EG-DMA) is added in one hour. The system is further kept at 90 °C for one hour and then neutralized with 60 g of 2fl a 30 per cent solution of NaOH. About 990 g of an amber-coloured polymer solution are obtained, having a total solids content of 30 per cent and a viscosity of about 350 cps at 20°C.
Example 5 This example reports the results of concrete tests made using the polymers of the present invention (Examples 1, 2 and 3) as superplasticizer in comparison both to a traditional superplasticizer based on naphthalene sulfonated formaldehyde condensate (NSFC) and a polymer synthetized using 14- ethyleneglycoldimethacrylate as crosslinking agent (14 EG-DMA) selected among those described in the Japanese Patent Application n. 281014 (Example 4). All the concretes were prepared with the same water/cement and aggregate/cement ratios, using Type I Portland cement (400 kg/mc) and coarse aggregate with maximum diameter of 20 mm. The comparative results of the concrete tests are reported in the following table.
Table 1. Comparative concrete tests using the additive of the present invention (Example 1, Example 2, Example 3) and a traditional superplasticizer based on naphthalene sulfonated formaldehyde condensate (NSFC) and a polymer obtained by using the crosslinking agents described in the Japanese Patent Application n. 281014 (Example 4).
Type of cement: Portland Type I.
Dosage of cement: 400 kg/cubic meter.
Coarse aggregate maximum diameter: 20 mm.
Water/cement ratio: 0.42.
Dosage of the different additives:
- Example 1: 0.25% active matter by weight of cement;
- Example 2: 0.25% active matter by weight of cement;
- Example 3: 0.25% active matter by weight of cement;
- Example 4: 0.25% active matter by weight of cement;
- NSFC . 0.50% active matter by weight of cement.
TYPE OF AIR SLUMP COMPRESSIVE
ADDITIVE CONTENT (mm) MECHANICAL
STRENGTH
(MPa) (%) after after after after 1 7 28 mixin 15 min 30 45 min da days da min s EXAMPLE 2.1 240 220 220 185 21 37 48 EXAMPLE 3.0 230 220 210 180 18 35 46 EXAMPLE 1.9 170 150 140 135 22 37 50 EXAMPLE 6.5 240 225 210 185 16 33 44 NSFC 2.1 180 120 80 60 22 38 47 The results of concrete tests of Table 1 clearly indicate that the fluidifying effect of the crosslinked polymer of the present invention (Examples 1, 2, 3) is much higher than that of the commercial additive based on naphthalene sulfonate (NSFC). In fact, the initial value of the fluidity of the concrete mixes (measured by "slump" test) containing the polymers of the present invention, even though at a dosage 50% less than NSFC, is higher or, at least comparable, with the mix containing NSFC.
Furthermore, the crosslinked acrylic polymer of the present invention (Examples 1, 2, 3) shows an excellent retention of the workability (very low "slump-loss"). So, results of Table 1 indicate that, even 45 minutes after the mixing, the concrete mixes additivated with the polymers of the present invention retain 80 per cent of the initial i3 2116381 "slump" value, while the "slump" of the concrete mix containing NSFC drops at 50 per cent of its initial value.
Also the air-entraining effect of the polymers of the present invention (Examples 1, 2, 3) is surprisingly low in comparison to the polymer of Example 4, which has been synthetized using polyethyleneglycoldimethacrylate (14EG-DMA) as crosslinking agent, as reported in Japanese Patent Application n. 281014.
Therefore, the crosslinking agent of the present invention, based on polypropyleneglycoldi(meth)acrylate, allows preparing cementitious mixes with a low air content without requiring the monomers described in the European Patent Applications n. 448717A and n. 0331308, which up to now were belived necessary in order to produce polymer superplasticizers characterized by a low air- entraining effect.
Example 6 In this example the polymer of the present invention has been evaluated as superplasticizer for High Alumina cement 2p based mortars. It is common knowledge that traditional superplasticizers like NSFC (Naphthalene Sulfonated Formaldehyde Condensate and MSFC (Melamine Sulfite Formaldehyde Condensate) do not exert significant fluidifying effect on High Alumina cement. The results of this example (see Table 2) surprisingly show that the polymer of the present invention, even at an exceptionally low dosage, exerts an excellent superplasticizing effect and retain the workability of the mixes based on High Alumina cement and do not cause any decrease in the strength developments.
Table 2. Comparative mortar tests using the additive of the present invention (Example 1, Example 2, Example 3) and a traditional superplasticizer based on naphthalene sulfonated formaldehyde condensate (NSFC).
Type of cement: High Alumina cement (Ciment Fondu, Lafarge) Sand/Cement ratio: 2.0 Water/Cement ratio: 0.30 Dosage of the different additives:
- Example 1: 0.1% active matter by weight of cement - Example 2: 0.1% active matter by weight of cement - Example 3: 0.1% active matter by weight of cement - NSFC . 0.5% active matter by weight of cement TYPE OF AIR FLUIDITY COMPRESSIVE
ADDITIVE CONTENT (%) MECHANICAL
(flow STRENGTH
table (MPa) measurement) (%) after after after after 1 7 28 mixing 15 min 30 min 45 min day days days PLAIN 4.8 15 15 12 10 78 102 111 EXAMPLE 5.0 140 140 130 125 81 100 110 EXAMPLE 4.9 135 135 130 120 80 99 105 EXAMPLE 5.0 132 130 125 118 82 102 109 NSFC 6.5 25 15 15 15 78 102 112
Claims (6)
1. Superplasticizing additive for concrete and other cementitious mixes with high retention of workability (low "slump-loss") and low air-entraining effect, characterized by terpolymerizing the following mixture of monomers respectively having formula IV
where Z = H, Na, Li, 1/2Ca and X is H or CH3; formula V
where W = -(-CH2-CH2-O-)n-CH3, n is an integer from 8 to 50 and X is H or CH3; and formula VI
where Y = and m is an integer from 2 and 50.
where Z = H, Na, Li, 1/2Ca and X is H or CH3; formula V
where W = -(-CH2-CH2-O-)n-CH3, n is an integer from 8 to 50 and X is H or CH3; and formula VI
where Y = and m is an integer from 2 and 50.
2. Superplasticizing additive according to claim 1, wherein the monomer of formula V is polyethyleneglycolmonomethyl-ether-(meth)acrylate of molecular weight from about 200 to about 2000.
3. Superplasticizing additive according to claims 1 or 2, wherein the monomer of formula VI is polypropyleneglycol-di-(meth)acrylate of molecular weight between about 280 and about 3100.
4. Superplasticizing additive according to any one of claims 1 to 3 wherein the amount of acrylic monomers (IV) and (V) ranges from 90 to 99.9 per cent of the whole polymerizable mass and the amount of monomer (VI) ranges from 0.1 to 10 per cent of the whole polymerizable mass.
5. Cementitious mixes containing from 0.01 to 3.00 per cent (as dry matter) by weight of the cement , of the additive as defined in any one of claims 1 to 4.
6. Cementitious mixes according to claim 5, wherein the cement used is High Alumina cement.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ITMI93A000366 | 1993-02-25 | ||
| ITMI930366A IT1263969B (en) | 1993-02-25 | 1993-02-25 | SUPERFLUIDIFYING ADDITIVES WITH HIGH CONSERVATION OF WORKABILITY |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2116381A1 CA2116381A1 (en) | 1994-08-26 |
| CA2116381C true CA2116381C (en) | 2004-06-22 |
Family
ID=11365161
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002116381A Expired - Lifetime CA2116381C (en) | 1993-02-25 | 1994-02-24 | Zero slump - loss superplasticizer |
Country Status (13)
| Country | Link |
|---|---|
| US (1) | US5362324A (en) |
| EP (1) | EP0612702B1 (en) |
| KR (1) | KR100287301B1 (en) |
| AT (1) | ATE145638T1 (en) |
| CA (1) | CA2116381C (en) |
| DE (1) | DE69400968T2 (en) |
| DK (1) | DK0612702T3 (en) |
| ES (1) | ES2095690T3 (en) |
| GR (1) | GR3022575T3 (en) |
| HK (1) | HK1006449A1 (en) |
| IT (1) | IT1263969B (en) |
| PH (1) | PH30174A (en) |
| TW (1) | TW266200B (en) |
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| US6166112A (en) * | 1997-03-10 | 2000-12-26 | Nippon Shokubai Co., Ltd. | Cement admixture and cement composition |
| FR2763064B1 (en) | 1997-05-12 | 1999-07-30 | Lafarge Sa | SELF-LEVELING CONCRETE AND METHOD FOR MAKING A CONSTRUCTION PART |
| US5854386A (en) * | 1997-08-25 | 1998-12-29 | Arco Chemical Technology, L.P. | Stabilizers for polymer polyols |
| US6294015B1 (en) * | 1998-01-22 | 2001-09-25 | Nippon Shokubai Co., Ltd. | Cement admixture and cement composition |
| FR2778913B1 (en) * | 1998-05-25 | 2000-06-23 | Gtm Construction | GROUND INJECTION, ITS USES AND ARTICLES INCLUDING SAME, KIT FOR THE PREPARATION OF THIS GROUT |
| IT1301974B1 (en) * | 1998-07-31 | 2000-07-20 | Atochem Elf Italia | WATER SOLUBLE ACRYLIC COPOLYMERS |
| US6265495B1 (en) * | 1998-09-22 | 2001-07-24 | Nippon Shokubai Co., Ltd. | Method for production of esterified product |
| FR2784048B1 (en) * | 1998-10-05 | 2000-12-15 | Lafarge Aluminates | TUBE INTERIORLY COATED WITH A CEMENTING COMPOSITION AND PROCESS FOR PRODUCING THE SAME |
| DE19854477C2 (en) * | 1998-11-25 | 2002-03-14 | Dyckerhoff Ag | Fastest-setting hydraulic binder composition and its use |
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| US6133347A (en) | 1999-07-09 | 2000-10-17 | Mbt Holding Ag | Oligomeric dispersant |
| US6503318B2 (en) | 2000-03-29 | 2003-01-07 | National Research Council Of Canada | Conductive concrete composition |
| US6448311B1 (en) | 2000-07-19 | 2002-09-10 | Baker Hughes Incorporated | Cement fluid loss additive |
| FR2815342B1 (en) | 2000-10-13 | 2003-08-01 | Francais Ciments | CEMENTITIOUS COMPOSITION, ITS USE FOR THE PRODUCTION OF A SELF-LEVELING LIQUID SCREW AND A SCREEN THUS OBTAINED |
| US6641754B2 (en) * | 2001-03-15 | 2003-11-04 | Betzdearborn Inc. | Method for controlling scale formation and deposition in aqueous systems |
| US6444747B1 (en) | 2001-03-15 | 2002-09-03 | Betzdearborn Inc. | Water soluble copolymers |
| FR2853646B1 (en) * | 2003-04-11 | 2007-07-06 | Chryso Sas | USE OF DISPERSANTS TO ENHANCE THE MAINTENANCE OF CONCRETE FLUIDITY |
| SE526347C2 (en) * | 2003-09-18 | 2005-08-30 | Perstorp Specialty Chem Ab | New copolymer and cement additive comprising the same |
| ES2305397T3 (en) * | 2003-12-22 | 2008-11-01 | Mapei S.P.A. | SUPERPLASTIFICANT THAT DEVELOPS A HIGH INITIAL RESISTANCE. |
| EP1655272A1 (en) * | 2004-11-04 | 2006-05-10 | Mapei S.p.A. | Superplasticizers for extending the workability of mortars |
| WO2006114124A1 (en) * | 2005-04-28 | 2006-11-02 | Pirelli Tyre S.P.A. | Tire and crosslikable elastomeric composition |
| CN100509683C (en) * | 2006-09-30 | 2009-07-08 | 江苏博特新材料有限公司 | Low molecular weight copolymer dispersant and preparing method thereof |
| EP2090596A1 (en) * | 2008-02-13 | 2009-08-19 | Construction Research and Technology GmbH | Copolymer with polyether side chains and hydroxyalkyl and acid building blocks |
| US7973110B2 (en) * | 2008-06-16 | 2011-07-05 | Construction Research & Technology Gmbh | Copolymer synthesis process |
| FR2949227B1 (en) * | 2009-08-21 | 2013-09-27 | Laboratoire Central Des Ponts Et Chaussees | GEOPOLYMERIC CEMENT AND USE THEREOF |
| EP2336094A1 (en) | 2009-12-21 | 2011-06-22 | Mapei S.p.A. | "Superplasticizers for concrete and cement materials and process for producing the same" |
| RU2469975C1 (en) * | 2011-05-26 | 2012-12-20 | Общество с ограниченной ответственностью Научно-производственное предприятие "Макромер" | Polycarboxylate plasticising additive for concrete, building mortars and dry construction mixes and method of its production (versions) |
| KR101355811B1 (en) * | 2012-08-20 | 2014-01-27 | 아주산업 주식회사 | Dry concrete mix composition |
| WO2014035221A1 (en) * | 2012-09-03 | 2014-03-06 | 주식회사 엘지화학 | Cement composition additive comprising cross-linked polycarboxylic acid-based copolymer, and cement composition comprising same |
| FR3013350B1 (en) * | 2013-11-15 | 2016-09-02 | Coatex Sas | FLUIDITE RETENTION AGENT FOR HYDRAULIC COMPOSITION COMPATIBLE WITH POLYMER-TYPE WATER-REDUCING AGENT |
| ITMI20132059A1 (en) | 2013-12-10 | 2015-06-11 | Mapei Spa | ACCELERATING ADDITIVE FOR CEMENTITIOUS COMPOSITIONS |
| CN105037652B (en) * | 2015-08-24 | 2017-11-10 | 科之杰新材料集团有限公司 | A kind of preparation method of high solids esters polycarboxylate water-reducer |
| CN105085824B (en) * | 2015-08-24 | 2018-09-07 | 科之杰新材料集团有限公司 | A kind of cross-linking type polycarboxylic acid slump retaining agent and preparation method thereof |
| US10662121B1 (en) | 2015-12-28 | 2020-05-26 | Concrete Products Group LLC | Concrete mixing and concrete products |
| CN105712649B (en) | 2015-12-31 | 2018-06-26 | 江苏苏博特新材料股份有限公司 | A kind of phosphoric acid polycondensates high efficiency water reducing agent and preparation method thereof |
| CN106117460B (en) * | 2016-08-26 | 2018-09-28 | 科之杰新材料集团有限公司 | A kind of preparation method of ethers viscosity reduction type polycarboxylate water-reducer |
| CN106478895B (en) * | 2016-10-09 | 2019-02-01 | 武汉工程大学 | A kind of compound polycarboxylate water-reducer of graphene oxide and preparation method thereof |
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| DE102017213607A1 (en) | 2017-08-04 | 2019-02-07 | Evonik Röhm Gmbh | Flow improver and water reducer |
| EP3549961A1 (en) | 2018-04-03 | 2019-10-09 | Evonik Röhm GmbH | Concrete flow improver and water reducing agent |
| KR20200038266A (en) | 2017-08-04 | 2020-04-10 | 룀 게엠베하 | Concrete fluidity improver and water reducing agent |
| CN109369860B (en) * | 2018-11-01 | 2021-03-19 | 中建材中岩科技有限公司 | Slow-release controllable polycarboxylate superplasticizer mother liquor and preparation method thereof |
| CN111100252A (en) * | 2019-12-22 | 2020-05-05 | 同济大学 | Synthetic method of polycarboxylic acid water reducer with high water reducing rate and super slump retaining property |
| CN113929342B (en) | 2020-06-29 | 2022-11-25 | 南京博特新材料有限公司 | Microcapsule type polycarboxylic acid superplasticizer and preparation method thereof |
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| US4473406A (en) * | 1982-06-21 | 1984-09-25 | National Starch And Chemical Corporation | Cementiferous compositions |
| JPS6234977A (en) * | 1985-08-08 | 1987-02-14 | Mitsui Toatsu Chem Inc | Water stopping agent |
| US4792360A (en) * | 1987-06-30 | 1988-12-20 | The Dow Chemical Company | Workable cement composition of low water content containing a hydroxyalkyl (meth)acrylate polymer |
| JPH02271953A (en) * | 1989-04-13 | 1990-11-06 | Mitsui Cyanamid Co | Mortar-concrete composition |
| JPH0660042B2 (en) * | 1989-04-24 | 1994-08-10 | 株式会社エヌエムビー | Cement composition fluidity reduction inhibitor and cement additive |
| DE3917815A1 (en) * | 1989-06-01 | 1990-12-06 | Roehm Gmbh | POLYMER MODIFIED BITUMEN |
| US5028271A (en) * | 1989-07-05 | 1991-07-02 | Nalco Chemical Company | Vinyl grafted lignite fluid loss additives |
| JPH06104585B2 (en) * | 1992-09-30 | 1994-12-21 | 株式会社日本触媒 | How to prevent slump loss in cement compounds |
-
1993
- 1993-02-25 IT ITMI930366A patent/IT1263969B/en active IP Right Grant
-
1994
- 1994-02-16 ES ES94102312T patent/ES2095690T3/en not_active Expired - Lifetime
- 1994-02-16 DK DK94102312.9T patent/DK0612702T3/en active
- 1994-02-16 EP EP94102312A patent/EP0612702B1/en not_active Expired - Lifetime
- 1994-02-16 AT AT94102312T patent/ATE145638T1/en active
- 1994-02-16 DE DE69400968T patent/DE69400968T2/en not_active Expired - Lifetime
- 1994-02-24 TW TW083101592A patent/TW266200B/zh not_active IP Right Cessation
- 1994-02-24 US US08/201,377 patent/US5362324A/en not_active Expired - Lifetime
- 1994-02-24 KR KR1019940003330A patent/KR100287301B1/en active IP Right Grant
- 1994-02-24 PH PH47832A patent/PH30174A/en unknown
- 1994-02-24 CA CA002116381A patent/CA2116381C/en not_active Expired - Lifetime
-
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Also Published As
| Publication number | Publication date |
|---|---|
| KR940019644A (en) | 1994-09-14 |
| GR3022575T3 (en) | 1997-05-31 |
| TW266200B (en) | 1995-12-21 |
| ATE145638T1 (en) | 1996-12-15 |
| ES2095690T3 (en) | 1997-02-16 |
| EP0612702A1 (en) | 1994-08-31 |
| DE69400968D1 (en) | 1997-01-09 |
| PH30174A (en) | 1997-01-21 |
| CA2116381A1 (en) | 1994-08-26 |
| ITMI930366A0 (en) | 1993-02-25 |
| HK1006449A1 (en) | 1999-02-26 |
| KR100287301B1 (en) | 2001-04-16 |
| DE69400968T2 (en) | 1997-04-03 |
| IT1263969B (en) | 1996-09-05 |
| DK0612702T3 (en) | 1997-04-28 |
| EP0612702B1 (en) | 1996-11-27 |
| ITMI930366A1 (en) | 1994-08-25 |
| US5362324A (en) | 1994-11-08 |
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