US3654244A

US3654244A - Polymers for soil-release textile finishes

Info

Publication number: US3654244A
Application number: US20096A
Authority: US
Inventors: Allen G Pittman; William L Wasley
Original assignee: US Department of Agriculture USDA
Current assignee: US Department of Agriculture USDA
Priority date: 1970-03-16
Filing date: 1970-03-16
Publication date: 1972-04-04
Anticipated expiration: 1989-04-04

Abstract

FLUOROCARBON ACRYLATES OR METHACRYLATES ARE COPOLYMERIZED WITH ACRYLATES OR METHACRYLATES WHICH CONTAIN ONE OR MORE ALKYLENOXY GROUPS. THE COPOLYMERS ARE USEFUL FOR APPLICATION TO FIBROUS MATERIALS TO PROVIDE BOTH SOIL REPELLENCY AND SOIL RELEASIBILITY.

Description

3,654,244 Patented Apr. 4, 1972 United States PatentGfice 3,654,244 POLYMERS FOR SOIL-RELEASE TEXTILE FINISHES Allen G. Pittman, El Cerrito, and William L. Wasley,

Berkeley, Calif., assignors to the United States of America as represented by the Secretary of Agriculture N Drawing. Filed Mar. 16, 1970, Ser. No. 20,096 Int. Cl.'C08f 15/16, 15/40 US. Cl. 26079.7 e 27 Claims ABSTRACT OF. THE DISCLOSURE Fluorocarbon acrylates or methacrylates are copolymerized with acrylates or methacrylates which contain one or more alkyleneoxy groups. The copolymers are useful for application to fibrous materials to provide both soil repellency and soil releasability.

A non-exclusive, irrevocable, royalty-free license in the invention herein described, throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to and has among its objects the provision of novel polymers which are particularly useful for imparting soil-repellent and soil-release properties to fibrous materials. The objects of the invention also include procedures for treating fibrous materials with the polymers, and the treated materials as new articles of manufacture. Further objects of the invention will be evident from the following description wherein parts and percentages are by weight unless otherwise specified.

It is not generally realized that maintaining textiles in a clean state involves two different properties of the textile. One is soil repellency, that is, the ability of the textile to resist staining when it is contacted with gravy, butter, grease, or other oily substances. The other is soil releasability. Assuming that a textile has become stained, this property concerns the ease or difliculty of washing out the stains. The soil repellency and soil releasability characteristics of a given textile on the kind of fiber from which it is made and the kind of finishing agent which has been applied to it. Natural fibers such as cotton and wool exhibit little soil repellency, but on the other hand when they do become soiled they are readily cleaned, that is, they exhibit a high level of soil releasability. Some of the synthetics, notably polyesters, not only exhibit a low level of soil repellency but also a low level of soil releasability. Thus the modern trend toward fabricating textiles from blends of cotton or wool with polyesters has aggravated the situation because such blends are easily soiled and the absorbed soil is difficult to wash out. The application of resins for providing durable press properties still further aggravates the soil release situation, Almost everyone has encountered a situation where a so-called wash-and-wear garment of resin-treated cotton/polyester or wool/polyester blended material has become soiled by contact with an oily substance, and it is: found that it takes repeated washings to remove the stains. In efforts to circumvent these problems, fluorocarbon polymers have been applied to the textiles. Because of oleophobic properties of most fiuorocarbons, such treatments do enhance the soil repellence of the fabric. However, they tend to make the soil release properties even worse because the aqueous washing medium cannot properly wet the fabric, hence cannot remove stains. Another remedy has been to apply hydrophilic materials, generally polymeric, to the textiles. These generally make it easier to wash out stains, but

they do not enhance the ability of the textile to resist staining when contacted with oily substances.

A particular object of the invention is to provide the means for alleviating the problems outlined above. The invention provides polymers which confer oil-repellence on fabrics so that they strongly resist staining, e.g., by oily foods or the like. Concomitantly, these polymers confer soil-release properties on the fabric to which they are applied- This means that if the fabric does become stained, the stains can be readily washed out.

The polymers having this desirable combination of properties are copolymerization products of at least two different monomers, one imparting olephobic properties, the' other hydrophilic properties. More specifically, the olephobic monomer is an acrylate or methacrylate which contains a terminal perfiuoroalkyl group of 3 to 18 perfluorinated carbon atoms, such group being hereinafter designated as R The hydrophilic monomer is an acrylate or methacrylate of an alcohol of the structure HO(AlkO) wherein Alk is an alkylene group containing 2 to 6 carbon atoms, x is an integer from 1 to 60, and R is a hydrocarbon radical containing 1 to 20 carbon atoms. The copolymers of the invention have a carbon-to-carbon backbone, plus pendant R groups which provide oleophobicity, and pendant groups of the structure (AlkO) R' which provide hydrophilic properties, The monomers used in accordance with the invention are described further in the following paragraphs.

THE OLEOPI-IOB'IC MONOMER As noted above, the oleophobic monomer used in accordance with the invention may be any acrylate or methacrylate which contains a terminal perfluoroalkyl group containing 3 to 18 perfluorinated carbon atoms. This perfluoroalkyl group can be of an open-chain (acyclic) configuration, straight or branched. Alternatively, it may be of a cyclic structure such as a perfluorocyclohexyl group, or it may be a combination of acyclic and cyclic structures. Generally, the acyclic structures are preferred. These monomers are known in the art and described in the literature. Illustrative examples of various sub-categories of monomers included within the generic ambit of the invention are described below.

Monomers of the structure:

wherein R is H or CH m is an integer from 1 to 12, and R is a perfluoroalkyl group containing 3 to 18 perfluorinated carbon atoms. Compounds in this sub-category are described in the following U.S patents: Ahlbrecht et al. 2,642,416 and 3,102,103; Langerak, 3,248,260; and Fasick et al., 3,282,905. Representative individuals in clude the following: 7

5C10F21 CH2: 11C3'F17 11-C F1q 12-CmFm and other acrylic (or methacrylic) acid esters of alcohols of the structure HO-(-CH -R wherein m and R are as hereinabove defined.

Monomers of the structure:

R o CHz=-AO-(CHz)r-ORf wherein R is H or CH n is an integer from 2 to 12, and R is a perfluoroalkyl radical containing 3 to 18 perfluorinated carbon atoms. Compounds in this sub-category are disclosed by Pittman and Wasley, U.S. Pats. 3,424,- 785, and representative individuals include the following: OH =CHCOO(CH OCF (CF z CH =C(CH CO -O(CH OCF CF 3 2 CH =CHCOO (CH O--CF(CF 2 CH =C CH CO-O( CH -OCTF C-F z CH =CHCO-OCH -CH OCF (C 1 z and other acrylic (or methacrylic) acid esters of alcohols of the type HO-('CH -OR; wherein n and R are as hereinabove defined.

Monomers of the structure:

CH2=o ilocH2-o F2-C F2-'0-Rf wherein R is H or CH and R is a perfluoroalkyl group containing 3 to 18 perfiuorinated carbon atoms. Compounds in this sub-category are disclosed by Bovey et al.,

US. Pat. 2,826,564, and representative examples include the following:

wherein R is H or CH and R is a perfiuoroalkyl radical containing 3 to 12 perfluorinated carbon atoms. Compounds in this sub-category are disclosed by the following US. Pats. Anello et al., 3,409,602, and Pittman and Wasley, 3,480,664. Representative individual compounds include the following:

this sub-category are disclosed by Pacini, US. Pat. 3,445,- 491, and representative individuals include the following:

and other acrylic (and methacrylic) acid esters of thioalcohols of the structure RI! HS(CHz) nl IC o-m wherein n, R", and R; are as above defined.

Monomers of the structure:

wherein R is H or CH m is an integer from 1 to 12, R" is H or lower alkyl, and R; is a perfluoroalkyl radical containing 3 to 18 perfluorinated carbon atoms. Compounds of this sub-category are disclosed in British Pat. 857,689, and representative individuals include the following:

wherein n, R, and R; are as above defined.

THE HY DROPHILIC MONOMER The hydrophilic monomer used in accordance with the invention has the structure:

wherein R is H or CH Alk is an alkylene group containing 2 to 6 carbon atoms, x is an integer from 1 to 60, and R is a monovalent hydrocarbon radical containing 1 to 20 carbon atoms and which may be in an alkyl, aryl, or aralkyl configuration. The nature of the hydrocarbon substituent R is of no criticality-it simply serves as an inert terminator of the alkyleneoxy chain.

These compounds are readily prepared, by esterifying (with acryloyl or methacryloyl chloride) the corresponding alcohols, i.e.,

These alcohols, in turn, are prepared by condensing an alkylene oxide such as ethylene or propylene oxide with an alkali metal alcoholate or phenolate, and then treating the intermediate with an acid, all as well known in the art. The condensation may be illustrated by the following equation as applied by way of example to ethylene oxide and potassium methylate:

7 Ho OH -CH }XCH Examples of individual monomers are provided below by way of illustration, wherein the symbol Ph stands for The acrylic or methacrylic acid esters of alcohols such as HOCH CHg-OCH (C2115 H0 (SH-CHf-OH 12-1 11 HO-(CHrCHz-Ohn-CHrPh PREPARATION OF THE COPOLYM-ERS The copolymers of the invention are prepared by conventional polymerization methods using bulk, solution, or emulsion techniques..The reactants may be copolymerized under the influenceof heat, light, or a combination of heat and light. The use of polymerization catalysts is preferred and for this purpose one may use peroxides such is benzoyl. peroxide, acetyl peroxide, lauroyl peroxide, ditert-butyl peroxide, or an azo initiator such as ot,ot'-3Z0- diisobutyronitrile or a,u' azobis (a,'y-dimethylvaleronitrile). Where the polymerization is conducted in solution, it is preferred to use dluorinated solvents, for example, benzotrifluoride, 1,3 bis (trifluoromethyD-benzene, trichlorotrifiuoroethane, or the like. 'In carrying out the copolymerization in solution, temperatures of about 50- 100 C. are generally used. The copolymer products range from viscous liquids to semi-solid or even solid materials. They are generally poorly soluble or even insoluble in common solvents suchas benzene, toluene, carbon tetrachloride and the like but soluble in fiuorinated solvents such as benzotrifluoride, 1,3-bis-(trifluoromethyl)-benzene, trichlorotrifluoroethane and the like. This property of the copolymers can be utilized for purifying them. For example, the copolymerization product can be dissolved in a fluorinated solvent and the purified copolymer precipitated out of solution by adding a common solvent such as benzene or toluene.

In preparing the copolymers of the invention, the proportions of the monomers may be varied depending on such factors as the number of perfluorinated carbon atoms in the oleophobic monomer, the number of alkyleneoxy group in the hydrophilic monomer, and the properties desired in the copolymer. In general, the monomers are used in the ratio of about from 0.1 to 3 moles of the hydrophilic monomer per mole of the oleophobic monomer, with the proviso that the copolymer contain at least 20% fluorine by weight.

The copolymers of the invention encompass those which are prepared by copolymerization of the oleophobic and hydrophilic monomers as above described plus one or more monomers which are different from both of the basic reactants. The additional monomer may be employed to modify the mechanical properties of the copolymer without materially affecting its ability to provide soil repellency and soil releasability. For such purpose one may use methyl, ethyl, butyl, or other alkyl acrylates or methacrylates, vinyl chloride, vinyl fluoride, ethylene, butadiene, etc. Monomers which may be used to increase the adherence of the copolymer to fibrous substrates include acryloyl or methacryloyl chloride, N-methylol acrylamide, allyl acrylate, etc. In the event an additional monomer is added to the copolymerization system, it is empoyed in a proportion up to about 1 mole per mole of the oleophobic monomer APPLICATION TO FIBROUS MATERIALS The copolymers of the invention are particularly useful for the treatment of fibrous materials, such as textiles, in order to enhance their oil-, water-, and soil-repellency and concomitantly to make it easier to remove stains if they should become stained. Moreover, these improvements are attained without detriment to other properties of the fibrous substrate. For example, the treatment does not impair the color, hand, or strength of the substrate. Another point is that the improvements are durable; they are retained despite laundering and dry cleaning of the treated materials.

In applying the copolymer to a substrate, a typical procedure involves dissolving the copolymer in an inert volatile solvent, e.g., benzotrifiuoride, 1,3-bis-trifluoromethyl benzene, or trichlorotrifiuoroethane. The resulting solution is applied to the substrate by immersion, brushing, spraying, flooding, or the like. With textiles, conventional dipand-pad techniques are preferred. By varying the concentration of copolymer in solution, the amount of copolymer deposited on the material may be varied. Typically, the amount of copolymer may be from 0.1 to 20%, based on the weight of fibrous material but it is obvious that higher or lower proportions can be used if desired. Usually, in treating textiles such as fabrics, the amount of copolymer is limted to about 0.1 to 5% to attain the desired repellency and soil release property without interference with the hand of the textile. In an alternative procedure, the copolymer is applied to the substrate, using water as the carrier for the copolymer. This is accomplished by forming an aqueous emulsion of the copolymer, using a conventional emulsifying agent to maintain the copolymer uniformily dispersed in the liquid. The emulsion is applied in any of the ways previously described and the amount of-copolymer applied to the substrate is likewise as above.

After application of the copolymer, the treated substrate is subjected to a curing operation in order to bond the polymer to the fibers. As an example of such treatment, the fibrous material is heated in the range of about 50 to 100 C. for a period of to 60 minutes. The carrier (from the copolymer solution or emulsion) may be evaporated in a separate step prior to curing or it may simply be evaporated during the curing operation.

In applying the copolymers of the invention to fibrous substrates, they may be accompanied by other substances, e.g., conventional finishing agents. Thus, a dispersion (i.e., solution, emulsion, or suspension) is made of an inert liquid carrier, the copolymer in accordance with the invention, and the additional substance which may be, for instance, a mothproofing agent, fungicide, coloring material, optical bleach, size, etc. The dispersion is applied and the treated fibrous material cured as disclosed previously. The inert liquid carrier may be water or any of the fluorinated solvents described above.

The invention may be utilized for improving the properties of all types of fibrous materials, for example, paper; cOtton; linen; hemp; jute; ramie; sisal; cellulose acetate rayons; cellulose acetate-butyrate rayons saponified acetate rayons viscose rayons; cupramrnonium rayons; ethyl cellulose; fibers prepared from amylose, algins, or pectins; wool; silk; animal hair; mohair; leather; fur regenerated protein fibers prepared from casein, soybean, peanut proteins, zein, gluten, egg albumin, collagen, or keratins; nylon; polyurethane fibers; polyester fibers such as polyethylene terephthalate; polyacrylonitrile-based fibers; or fibers of inorganic origin such as asbestos, glass, etc. The invention may be applied to textile materials which are in the form of bulk fibers, filaments, yarns, threads, slivers, roving, top, webbing, cord, tape, woven or knitted fabrics, felts, or other non-woven fabrics, garments or garment parts.

EXAMPLES The invention is further demonstrated by the following examples which are provided by way of illustration, not limitation.

Test methods The tests referred to in the examples were carried out as described below:

Oil repellency: The test used was the AATCC Test Method 118-1966T. Ratings are from 0 to 8 with the higher values signifying the greater resistance to oil penetration. In particular, the oil-repellency rating is the highest-numbered test liquid which will not wet the fabric in within a period of seconds. The liquids and their corresponding numbers are:

Soil release evaluation: This item was determined by examining the ease (or difiiculty) of removing mineral oil stains upon washing the stained fabric in an aqueous medium containing a nonionic detergent. The test was carried out as follows: A 4" x 4" fabric swatch was laid flat over a piece of absorbent paper and 3 drops of Nujol mineral oil were placed on the center of the fabric. A sheet of non-absorbent (glassine) paper was placed over the fabric and a l-pound weight was deposited over the area of the oil drops. The oil was allowed to penetrate into the fabric for 1 minute. After this, the weight and glassine paper were removed, and excess oil was blotted away with absorbent paper. The fabrics were then washed within a'2-hour period after staining. The washing consisted of agitating 2 to 4 such 47' x 4" swatches in a l-quart glass jar half filled with an aqueous detergent solution at 50 C. The detergent used was a lowsudsing non-ionic built-type which has been prescribed in the AATCC test method 1304969. About 10' grams of detergent per gallon of water was used. Agitation was applied for 5 minutes. After this'the fabric samples were rinsed with water, dried, and examined for residual oil stains. Where the fabric still remained ina stainedcondition, it was subjected to repeated washing in the same manner as described, the number of washings to-remove the stains providing an index of the soil-release property of the fabric. In staining some of the fabrics which had been treated with the fluorocarbon copolymers, it was necessary to use a special technique because the mineral oil tended to bead up and fail to penetrate the fabric even under the influence if the l-pound weight. This technique consisted of first placing 2-4 drops of heptane in the center of the fabric, followed by 3 drops of mineral oil. The heptane in these cases pre-wet the fabric and acted as a carrier for the mineral oil.

Monomers used The following fluorocarbon acrylates (or methacrylates) were used in preparing the copolymers. These monomers were obtained commercially or prepared in accordance with the patent citations given above.

The following acrylates or methacrylates were used as the hydrophilic monomers.

0112:011-0 o-o omonro CpHm (wherein r has an average value of 12).

Monomer L was purchased from a commercial source.

Monomer M was prepared by dropwise addition of monomethyl ether of diethylene glycol to a 2-fold molar excess of methacryloyl chloride held at 40 C. A nitrogen purge was maintained throughout the addition and for a half hour after the addition had been completed. After this, excess methacryloyl chloride was removed under vacuum, and the product distilled under vacuum to obtain a yield of monomer M, B.P. 90-96" C. at 1 mm. Hg.

Monomer N was prepared in the same manner by dropwise addition of monomethoxy polyethylene glycol (av. mol. wt. 350) to an excess of acryloyl chloride under a nitrogen purge. In this case, excess acryloyl chloride was removed under vacuum but the product was not distilled because of its high boiling point and the possibility of decomposition and polymerization during distillation. Examination of the product by infrared showed that there was no residual acryloyl chloride and that esterification was complete.

, Monomer .wasprepared in amanner similarto the preparation of' monomer except that a nimomethoxy polyethylenglycol of averagei'nolecular weight ZSOjNa's' added to an excess of methacryloyl chloride. f

Monomer P was prepared 'n a manner similar to the preparation of monomer N, except thata nonylphenoxy polyethylene glycol containing "about 12 CH 'CH -'O units was added to anexcess ofacryloyl chloride EXAMPLE 1- I Copolymer of M A solution was preparedlfrom 0.0;; rnole of monomer A and 0.01 moleof monomer M in 5 ml. of 1,3-bis-(trifluoromethyl)-benzene.Approximately 0.15 gram of a,a'- azobisisobutyronitrile was added and the solution in a closed container was heated on the steam bath 4 hours. The viscous solution which resultedwas mixed with benzene to precipitate polymer. The precipitated polymer was dissolved in trichlorotrifluoroethane, and reprecipitated by addition of benzene. The polymer was placed in a vacuum oven held at 80 C. and 1 mm. Hg for 2 hours to remove solvent. A rubbery polymer was obtained in 90% conversion. EXAMPLE 2 Copolymer of D and P Copolymerization was conducted in a manner similar to Example 1, using a 4/1 mole ratioof DH and 1 mole percent of the azo initiator.

EXAMPLES Copolymer of B and N In this case N-met'hylolacrylamide was included with the other monomers in order to form a polymer containing pendant methylol groups which are capable of crosslinking and producing a more durable polymer coating on textiles treated therewith.

Ten parts of-N-methylolacrylamide, four parts of sodium lauryl sulphate, and 200 parts of de-oxygenated water were mixed in a blendor. Then, 45 parts of monomer E and 45 parts 'of monomer L were added and the mixture homogenized for several mixtures. The mixture was then transferred to a flask equipped with a stirrer wherein it was heated to 40-50 C. under a nitrogen blanket. A solution containing one part of potassium persulphate in 40 parts of de-oxygenated water was added and the mixture heated at 50 C. for 6 hours. An aqueous suspension of the terpolymer was obtained which was used (after proper dilution) for fabric treatment. In a separate step by precipitation of the polymer, it was determined that the emulsion contained about 30% of the terpolymer.

Fabric treatment The fabrics used in the treatments were a 50/50 wool/ cotton blend and a 50/50 wool/polyester blend. Both of these fabrics had been rendered resistant to felting shrinkage by applying the interfacial polymerization (IFP) technique disclosed in US. Pat. 3,078,138, the complementary agents used being hexamethylene diamine and sebacoyl chloride. Since this shrinkproofing treatment had been uniformly applied to all the fabrics, it is not a variable in any of the experiments reported below.

Treatment of the fabrics with the copolymers of the invention were carried out by immersing the fabrics in a solutio of the copolymer in trichlorotrifluoroethane or 1,3-bis-trifiuoromethyhbenzene. In some cases the copolymer' was applied a'san aqueous emulsion. After immersion in the solution of emulsion, the fabrics were run through squeeze rolls to obtain a' 50-60% wet pick up. The treated fabrics were then air-dried and cured'in an oven at C. for 10 minutes. After removal from the oven and cooling to room temperature, the products were testedfor oil repellency and for soil release as previously described. In some instances the fabrics, prior to application of the fluorocarbon copolymers, were treated with dimethylol dihydroxyethylene urea (DMDEU) in order to impart durable press properties and to examine the eifectiveness of the fluorocarbon copolymers in the presence of this conventional finishing agent. The durable press fabrics were prepared as follows: A 20% aqueous solution of DMDEU containing approximately 0.5% Zn (NO catalyst and 0.2% of a non-ionic detergent was prepared. Fabrics which had been subjected to the IFP shrinkproofing treatment were immersed in this solution, then squeezed to a wet pick-up of 40-50%. The fabric swatches were air-dried, pressed for 1 minute on a high-heat (350 F.) press and then cured in an oven at 325 F. for 15 minutes.

EXAMPLE 6 Treatment of wool/cotton blend 'with copolymer A-M Wool/cotton with Wool/cotton without DMDEU DMDEU No. of Washes to remove oil stain No. of washes to remove oil stain Copolymer and concentration in solution A-M, 5%. 4 4 1 None (control) Oil repellency Oil repellency EXAMPLE 7 Treatment of wool/polyester blend with copolymer D-P In this case the fabric was the wool/polyester blend. Copolymer D-P, prepared as in Example 2, was applied as 1% and 3% solutions. The results are tabulated below:

No. of Copolymer and washes to concentration remove in solution oil stain D-P, 1% e 1 D-P, 3% 7 a 1 None (control) 0 4 Oil repellency EXAMPLE 8 Treatment of cotton/wool blend with copolymers B-N and C-B-O In this case the fabric was the Wool/cottonblend, with and without DMDEU pretreatment. Copolymer B-N- (Example 3) and C -BO (Example 4) were applied as 2% solutions. The results are tabulated below:

Wool/cotton with Wool/cotton without DMDEU DMDEU B-N 7 1 7 1 C-B-O 6 1 6 1 None (control) 0 4 0 3 No. of washes 1 1 EXAMPLE 9 Treatment of wool/ polyester blend with copolymer of E, L, and N-methylolacrylamide The emulsion prepared in Example 5 was diluted with enough water to give a copolymer concentration of 3%. This emulsion was then applied to the wool/polyester blend. The results given below:

' Oil repellency No.

' After 4 to remove copolymer Initial. 'washes oil stain E-L plus N-methylolamide 6 5 1 None (control) 0 0 4 wherein R is H or CH Alk is an alkylene group containing 2 to 6 carbon atoms, at is an integer from 1 to 60, and R is a monovalent hydrocarbon group containing 1 to 20 carbon atoms,

(c) in the proportion of about 0.1 to about 3 moles of monomer b per mole of monomer a, with the proviso that the copolymer contain at least 20% fluorine by weight,

((1) which copolymer is suitable for use as a soil repellent and soil release coating on fibrous materials.

2. The copolymer of claim 1 wherein monomer a is (JH2=t:i':o(CH2)m-R,

wherein R is H or CH m is an integer from 1 to 12, and R; is a perfiuoroalkyl group containing 3 to 18 perfiuorinated carbon atoms.

3. The copolymer of claim 1 wherein monomer a is CHg=(! i]O(CH2)n-0R1 wherein R is H or CH n is an integer from 2 to 12, and R; is a perfiuoroalkyl radical containing 3 to 18 perfluorinated carbon atoms.

4. The copolymer of claim 1 wherein monomer a is wherein R is H or CH m is an integer from 1 to 12, R" is H or lower alkyl containing 1 to 4 carbon atoms, and R is a perfiuoroalkyl radical containing 3 to 18 perfiuorinated carbon atoms.

5. The copolymer of claim 1 which includes recurring units derived from N-methylol acrylamide.

6. The copolymer of claim 1 wherein, in monomer b, Alk is CH --CH 7. The copolymer of claim 1 wherein, in monomer b, x is 1 to 20.

8. The copolymer of claim 1 wherein, in monomer b, Alk is CH CH and x is l to 20.

'9. The copolymer of claim 1 wherein monomer b is 'a mixture of congeners wherein Alk is -CH CH and x has an average value of 2 to 20.

10. A process for modifying a fibrous substrate which comprises depositing on the substrate a copolymer of (a) a monomer of the group'consisting of acrylates and methacrylates wherein the alcohol moiety contains a terminal perfiuoroalkyl group of 3 to l8 perfluorinate'd carbon atoms, and" i i i (b) a monomer of the formula 8 CH2 O (OH2)m Rf v wherein R is H or CH m is an integer from 1 to 12, and R, is a perfiuoroalkyl group of 3 to 18 perfluorinated car bon atoms.

12. The process of claim 10 wherein monomer is a R o CH2=(J(JO(CH2)m-ORr wherein R is H or CH m is an integer from 2 to 12, and R, is a perfiuoroalkyl group of 3 to 18 perfluorinated carbon atoms.

13. The process of claim 10 wherein monomer a is wherein R is H or CH m is an integer from 1 to 12, R"

is H or lower alkyl containing 1 to 4 carbon atoms, and

R; is a perfiuoroalkyl group of 3 to 18 perfiuorinated carbon atoms.

14. The process of claim 10 wherein the copolymer in} cludes recurring units derived from N-methylol acrylamide.

15. The process of claim 10 wherein, in monomer b, Alk is CH CH 16. The process of claim 10 wherein, in monomer b, x is 1 to 20.

17. The process of claim 10 wherein, in monomer b, Alk is -CH CH and x is 1 to 20.

18. The process of claim 10 wherein monomer b is a mixture of congeners wherein Alk is CH -CH and x has an average value of 2 to 20.

19. As an article of manufacture, fibrous material carrying a deposit of a copolymer of (a) a monomer ofthe group consisting of acrylates and methacrylates wherein the alcohol moietycontains a terminal perfiuoroalkyl group of 3 to 18 perfiuorinated carbonatoms, and

(b) a monomer of the formula l u oHt=C-oo- Alk-0 wherein R is H or CH Alk is an alkylerle group containing 2 to 6 carbon atoms, x is an integer from 1 to 60, and R is a monovalent hydrocarbon g roup containing 1 to 20 carbon atoms,

(c) in the proportion of 0.1 to 3 moles of monomer b per mole of monomer a, with the proviso that the copolymer contain at least 20% fluorine by weight.

20. The article of claim 19 wherein monomer a is wherein R is H or CH m is an integer from 1 to 12, and R, is a perfiuoroalkyl group of 3 to 18 perfluorinated carbon atoms.

21. The article of claim 19 wherein monomer a is ]t (H) CLD=U-C--O-(UlI;;) O--R '22: The article of claim 19 wherein monomer a is:

WhereinR is H or CH m is an integer from 1 to 12, R

isH or lower alkyl-containing-1'to-4 carbon atoms, and R is a-perfluoroalkyl group of 3 to 18 perfiuorinatedcarbon atoms.

a 23. The article of claim 19 wherein the copolymer contains recurring units derived from N-methylol acrylamide.

24. The article of'claim 19 wherein, in monomer b,

is CH -CH 25. The article of claim 19 wherein, in monomer b, x is l to 20. I

26. The article of claim 19' wherein, in monomer b, Alk is CH- -CH and x is 1 to 20.

27. Thearticle of claim 19wh'e'rein monomer b is a 14 mixture of congeners wherein Alkis -CH CH and xhasan averageiralueofZtd 20;

References Cited 7 'UNITEDSTATES PATENTS 3,282,905 11/1966 Fasick et al. 26089.5

3,424,785 1/ 1969 Pittman et a1. 260480 3,445,491 5/1969 Pacini 260399 3,453,345 7/1969 Mabrey et al. 260834 JOSEPH L. SCHOFER, Primary Examiner S. M. LEVIN, Assistant Examiner US. Cl. X.R.

26080.7, 80.73, 80.75, 80.76, 80.8, 80.81, 86.1 E, 86.1 N, 486 R; 8116 R, 116.2, 127.5 127.51, 128, 129; 117-12691, 126 GR, 138.8 F, 138.8 UA, 138.8 UP, 141, 142, 145, 155 UA, 161 UT, 161 UZ; 2608, 17.4 CL, 33.8 F

Disclaimer 3,654,244.Allen G. Pittman, El Cerrito, and William L. Wasley, Berkeley,

Calif. POLYMERS FOR SOIL-RELEASE TEXTILE FIN- lsHEs. Patent dated Apr. 4;, 1972. Disclaimer filed Nov. 3, 1973, by the ass1gnee, United States of America as represented by the Secretary of Agriculture. Hereby enters this disclaimer to claims 1-27 of said patent.

[Ofiicial Gazette July 1, 1.975.]