CA1103397A

CA1103397A - Fluorine-containing terpolymers

Info

Publication number: CA1103397A
Application number: CA299,941A
Authority: CA
Inventors: Albert L. Lore; Stuart Raynolds
Original assignee: EI Du Pont de Nemours and Co
Current assignee: EIDP Inc
Priority date: 1977-03-31
Filing date: 1978-03-29
Publication date: 1981-06-16
Also published as: IT1094023B; IT7821807A0; US4127711A

Abstract

ABSTRACT
Terpolymers comprising (i) from 55 to 80 percent by weight of units derived from a perfluoroaliphatic acrylate or methacrylate monomer, (ii) from 15 to 35 percent by weight of units derived from a nonfluorinated polyethylene oxide acrylate or methacrylate monomer, and (iii) from 1 to 15 percent by weight of units derived form a nonfluorinated dialkylaminoethyl acrylate or methacrylate monomer in its free base, amine salt, quaternary ammonium, or amine oxide form. The terpolymers are useful in oil and water repellency applications.

Description

3~37 BACKGROUND OF THE INVENTION
This invention relates to fluorine-containing oil-and water-repellent terpolymers.
Fluorine-containing polymers are known which impart oil and water repellency to substrates such as fabric and paper. There is nothing in the art, however, that teaches the terpolymers of this invention. The instant terpolymers have excellent oil and water repellency properties as well as unique aqueous and organic solubility properties. The ter-polymers are particularly useful for treating substrateswhere mild drying conditions are desirable, such as woolen apparel, upholstery fabrics and leather.
SU~ ~ RY OF THE INVENTION
This invention concerns terpolymers comprising (i) from 55 to80 percent by weight of units derived from a perfluoroaliphatic monomer of the formula RfQo2cc(R)=cH2 wherein Rf is a straight or branched-chain perfluoroalkyl group containing from 2 to 20 carbon atoms, R is H or CH3, Q is alkylene of 1 to 15 carbon atoms, hydroxy-alkylene of 3 to 15 carbon atoms, ~CnH2n(OCqH2q)m~, -SO2NR (CnH2n)-, or -CONR (CnH2n)-, Rl is H or Cl 4alkyl, n is 1 to 15, q is 2 to 4, and m is 1 to 15;
(ii) from 15to 35percent by weight of units derived from a nonfluorinated polyethylene oxide acrylate or methacrylate monomer of the formula R (OCH2CH2)p02CC(R)=CH2 il'~;~397 wherein s Cl_lsalkyl~aryl or C7_24alkaryl, R is H or CH3, p is 10 to 50; and (iii) from lto15percent by weight of units derived from a nonfluorinated monomer selected from the group CH2=C(R)CO2CH2CH2NR R , (CH2 = C(R)Co2CH2CH2~3R R5)y~ Y, and CH2 - C(R)Co2CH2CH2NR3R (O) wherein R is H or CH3, R3 and R are Cl 4alkyl, R5 is H or Cl 4alkyl, and X is an anion of valence y.
The terpolymers described hereinabove are prepared from the essential monomers defined in (i), (ii) and (iii~ by known solvent polymerization techniques. Weight percentages of the various terpolymer components and solution ingredicll~s are approximate. Terpolymexs deviating slightly in component percentages from those described specifically herein are included provided utility is not adversely affected.
Preferred weight ratios of the components of the terpolymer of this invention, based on total weight of the terpolymer, are: (i) 68 to 78 weight percent, (ii) 18 to 25 weight percent, (iii) 3 to 8 weight percent. A particularly ~xeferred terpolymer of this inventlon comprlses 75 weigh~
percent of monomer (i) RfCH2CH2O2CC(CH3)=CH2 wherein Rf is perfluoroal~yl of 4 to 14 carbon atoms, 20 weight percent of a monomer (ii) p-CgHlgC6H4(OCH2CH2~37O2CC(CH3)=CH2 and 5 weight percent of a monomer (iii) CH2=C(CH3)CO2CH2CH2N(C2H5)2(O).

'3397 DETAILS OF THE INVENTION -The fluorinated monomers of RfQO2CC(R)=CH2(i) are Rf-alkylene -O2CC(R)=CH2, as disclosed in U.S. Patents

2,642,416, 3,384,627, 3,392,046, 3,282,905, 3,532,659 and

3,102,103; Rf(hydroxyalkylene)O2CC(R)=CH2 as disclosed in U S Patent 3,514,420; RfCnH2n(OCqH2q)m 2 2 closed in British Patent 1,243,106; RfSO2NR (CnH2n)O2CC(R)=CH2 is disclosed in U.S. Patent 2,803,615; and RfCONRl(CnH2n)-O2CC(R)=CH2 as disclosed in U.S. Patents 3,304,278 and 3,578,487.
A particularly preferred monomer (i) has the formula RfCH2CH2OCOC(R)=CH2, wherein Rf and R are as defined.
Such monomers are known and can be prepared by either esteri-fication of the appropriate alcohol, RfCH2CH2OH, with acrylic acid or methacrylic acid or by transesterification with methylacrylate or methylmethacrylate, for example, as described in U.S.-3,282,905. The methacrylate esters are preferred over the acrylate esters. The perfluoroalkyl group, Rf, can be either straight or branched chain, with the former being preferred. The monomers, RfCH2CH2OCOC(R)=CH2, can contain a single perfluoroalkyl group, for example, perfluorooctyl, or a mixture of perfluoroalkyl groups~ The alcohols, RfCH2CH2OH, are commercially available as mixtures wherein Rf contains about 4 to 14 carbon atoms, predominantly six and eight car-bon atoms. Monomers prepared from such alcohol mixtures are preferred~
The most preferred perfluoroaliphatic monomer (i) is that wherein R is CH3 and Rf is a mixture of perfluoroalkyl groups, CF3CF2(CF~)r-, wherein r is 2, 4, 6, 8, 10 and 12 in the approximate weight ratio of 2/35/30/18/8/3; such a monomer has a weight average molecular weight of 522. The corresponding llQ;~397 acrylate monomer has a weight average molecular weight of 508.
The nonfluorinated polyethylene oxide-containing monomer (ii) has a weight average molecular weight of the poly-oxyethylene chain from about 440 to 2200. The monomer is pre-pared by esterification of the appropriate ethoxylated alcohol, R2(OCH2CH2)pOH, with acrylic or methacrylic acid by conven-tional procedures. The methacrylate esters are preferred over the acrylate. A particularly preferred polyoxyethylene methacrylate monomer (ii) is that obtained by esterification of methacrylic acid with the reaction product of nonylphenol and 37 moles of ethylene oxide. Alcohols such as octylphenol, stearyl alcohol, dodecyl alcohol, octyl alcohol, methanol and the like can be used in place of nonylphenol.
The third essential monomer (iii) used in the ter-polymer of this invention is dialkylaminoethyl acrylate or methacrylate monomer as either the free base, amine salt, quaternary ammonium or amine oxide form. The preferred quaternary ammonium monomer is:

2 C(CH3)cO2cH2cH2N(c2H5)2x ' The preferred amine salt monomer is:
H2 C(CH3)C2CH2CH2N(C2H5)2X ' The preferred amine oxide monomer is:
2 C(CH3)cO2cH2cH2N(c2H5)2 The basic dialkylaminoethyl acrylate or methacrylate monomers operable herein are known in the art and can be prepared by either reacting a tertiary amine alcohol of the formula, HoC2H4NR3R4, with acrylic or methacrylic acid or by trans-esterification with methylacrylate or methylmethacrylate.

The quaternary ammonium monomers are prepared by reacting the resulting esters with a di-(lower alkyl~sulfate or a lower alkyl halide. Dimethyl sulfate and diethyl sulfate are preferred quaternizing agents The amine salt monomers are prepared by reacting the afore~aid esters with an organic or inorganic acid, such as hydrochloric, hydrobromic, sulfuric or, preferably, acetic acid.
The amine oxide monomers are prepared by reaction of the aforesaid acrylate or methacrylate esters with conven-tional oxidizing agents such as hydrogen peroxi~e or peraceticacid and the like. Peracetic acid is a preferred oxidizing agent.
The nature of the anion, X, in the quaternary ammonium &nd amine salt monomers is, in general, determined by the method o~ synthesis. Usually X is a halide ion, such as chloride, bromide or iodide or an acetate ion, or an alkyl sulfate ion. It is known, however, that quaternary ammonium salts can also be prepared by reacting a tertiary amine with an alkyl ester of benzene or toluenesulfonic acid; ln such event, X is a benzenesulfonate or a toluenesulfonate anion.
In all cases, the an~on, X , will be water-solubilizing The terpolymer of the invention is obtained by polymerizing essential monomers (i~, (ii~, and (iii~ using conventional solvent polymerization techniques. Any of the conventional neutral æolvents, for example ethyl acetate, acetone, ethanol and, in psrticular, isopropanol can be used. The resulting terpolymers can, if desired, be isolated readily by evaporation of the solvent.
Alternatively, and preferably, the tertiary amine groups in the diethylaminoethyl acrylate or methacrylate monomer !iii~ are converted into the amine salt, quaternary ammonium or amine oxide form after polymeriza tion by acidifica-tion, quaternization or oxidation as described hereinabove.
Any conventional free-radical catalyst which is soluble in the solvent system can be used. Particularly pre-ferred are azo compounds such as azobisisobutyronitrile and peroxides such as t-butyl hydroperoxide. Catalyst concen-tration is suitably within the range of 0.1 to 2~ based on the weight of the charge.
Conventional chain transfer agents, such as d~d~cyl-mercaptan and isooctyl thioglycolate can be used in amountsof 0.1 to 2 percent by weight of the monomer to control the molecular weight of the polymer.
The terpolyr,ler solutions prepared as described above are usually more concentrated than needed or desired for application to the substrate and may be diluted to the desired concentration using the polymerization solvent and/
or water.
Utility The terpolymers of this invention are useful to impart oil, water, and soil repellency to a wide range of substrates. Due to their unique combination of aqueous and organic solubility and repellency properties, the terpolymers of this invention are particularly suitable for treating substrates such as woolen apparel, upholstered furniture, delicate fenestration fabrics and leather, where mild drying conditions are desirable.
Fluorinated copolymers are known in the art, e.g., in U.S. 3,637,614, which have excellent water and oil repellency when used in treating textile fahrics. Use of solutions of such copolymers in quick-drying chlorinated and fluorinated solvents such as trichloroethylene, trichloro-trifluoroethane, and difluorotetrachloroethane avoids exposure of delicate substrates to levels of heat which are harmful to the substrates. However, use of such solvents is sometimes commercially unattractive. Halogenated solvents are not necessary to produce quick-drying solutions of the terpolymers of this invention which are also characterized by excellent water and oil repellency.
The terpolymers of this invention are applied to fabric, such as polyester fabric,from alcohol or aqueous-alcohol solution by conventional means such as by spraying, dipping, padding or roller-coating to provide a treated fabric which, after drying, has excellent resistance to oily and aqueous stains.
Eight parts of 100% woven polyester fabric was immersed in a solution of 0.1 part of the terpolymer solids prepared in Example 1 dissolved in 20 ml of absolute ethanol.
The treated fabric was air-dried and then oven-dried for 3 minutes at 80~C and then tested for oil and water repellency.
Oil repellency was determined using AATCC Standard Test Method 118-1972 of the American Association of Textile Chemists and Colorists. This test comprised placing a drop of one of eight test solutions carefully on the fabric on a flat hori-zontal surface. The nature of the test solutions was as follows:

Oil Repellency TestSurface Tension, Rating Solutiondynes/cm at 25C
8 n-Heptane20.0 7 n-Octane 21.8 6 n-Decane 23.5 n-Dodecane25.0

4 n-Tetradecane 26.7 3 n-Hexadecane 27.3 2 65/35 hexadecane- 29.6 "Nujol"
1 "Nujol"*(puri- 31.2 fied petroleum oil) After thirty seconds any penetration or wicking into the fabric wasnoted visually. Treated fabrics with a rating of five or greater are good or excellent; anything with a rating of one or over can be used for certain purposes. As an example, if a treated fabric repels the Nos. 1-6 solutions but not the number 7 solution, its rating is 6.
Water repellency of the treated fa~ric was deter-mined by carefully placing a drop of one of five test solu-tions on each of three locations at least two inches apart.
The nature of the test solutions wasas follows:
Water Repellency Test Rating Solution 30/70 isopropanol-water 4 20/80 isopropanol-water 3 10~90 isopropanol-water 2 5/95 isopropanol-water 3n 1 2/98 isopropanol-water If, after ten seconds, two of the three drops of the lowest numbered test solution were still visible as spherical or hemispherical, drops of the next higher numbered test solution * d~note9 trade m~r~

were placed on an adjacent site and observed for ten seconds. This procedure wascontinued until one of the test solutions resulted intwo of the three drops failing to remain spherical or hemispherical. The water repellency rating of the fabric corresponded tothe highest numbered test solution for which two of the three dropsremainedspherical or hemi-spherical for at least ten seconds. The higher the water repellency rating, the better the resistance to staining by water-based substances.
The polyester fabric treated with the terpolymer of Example 1 rated very high on both repellency scales exhibiting a 6 oil repellency rating and a 4 to S water repellency rating.
The following examples illustrate the invention.
Unless otherwise indicated, all parts and percentages are by weight. The percent by weight of monomer units in the terpolymers is based on the weights of monomers charged.
Exam~le 1 A vessel was charged with 4939 parts of a fluorinated monomer (i) having the formula 3cF2(cF2)rc2H4o2cc(cH3)=cH
wherein r is 2, 4, 6, 8, 10 and 12 in the respective relative amounts of 2:35:30:18:8:3 as determined by gas phase chroma-tographic analysis, said monomer having a weight average molecular weight of 522. The vessel was also charged with 1317 parts of a polyoxyethylene methacrylate monomer (ii) having the formula C9Hl9 ~ -(0C2H4)3702cc(cH3) CH2 The vessel was also charged with 329 parts of nonfluorinated monomer (iii) of ~he formula, 2 C(CH3)C02cH2cH2N(c2H5~2 and 11,176 parts of isopropyl alcohol. The charge was stirred at room temperature under a nitrogen atmosphere. Peracetic acid (40~, 439 parts) was then added and the charge was heated to 60C over 30 minutes and then stirred at 60C for 1 hour.
Isooctyl thioglycolate (63.8parts) and 263 parts of distilled water were then added. The monomer mixture was heated to 84C over 1.5 hours and then refluxed for 40 minutes. Azobis-isobutyronitrile (79.1 parts) was then added to initiate polymerization and the charge was stirred for 17 hours at 78to83Oc under nitrogen. Distilled water (6810 parts) was added and the charge was heated to 58C and then filtered to yield 24,834 parts of terpolymer solution. The polymer solids (24.7~) in this solution contained 75 percent of perfluoroalkylethylmethacrylate monomer units (i); 20 percent of polyethoxylated nonylphencl methacrylate units (ii); and 5percent of N,N-diethylaminoethylmethacrylate amine oxide units (iii).
Example 2 .
Example 1 was repeated using 60 parts of the fluorinated monomer, 32 parts of the polyethoxylated nonylphenol methacrylate monomer, 8 parts of N,N-diethylaminoethyl methacrylate and 155 parts of isopropyl alcohol. Peracetic acid (40~, 9 parts) was added and the monomer mixture was stirred at 60C for 1 hour. Isooctyl thioglycolate ~0.23 part) and 1 part of azobisisobutyronitrile were added and the mixture was refluxed for 18 hours to complete the polymerization. A total of 261 parts of terpolymer solution was obtained. The polymer solids (36.3%) contained 60 percentofperfluoroalkylethyl methacrylate units, 32percent of polyethoxylated nonylphenol methacrylate units and 8percent of N,N-diethylaminoethylmethacrylate amine oxide units.

Examples 3 to 10 A series of terpolymers was made by polymerizing a fluorinated monomer,CF3CF2(CF2)rC2H4O2C ( 3 2 r is 2, 4, 6, 8, 10 and 12, a nonylphenol methacrylate monomer containing 37 units of ethylene oxide and a N,N-diethylamino-ethylmethacrylate monomer using the general procedure of Example 1. In Examples 3 to 8, the polymerization solvent was a 75:25 mixture of ethyl alcohol and water. Examples g and lOusedisopropyl alcohol as the solvent. The chain transfer agent and the initiator employed were isooctylthioglycolate and azobisisobutyronitrile, respectively. After polymerization, the diethylaminoethylmethacrylate units in the terpolymer were functionalized by conversion to the amine acetate salts by the addition of acetic acid (Examples S and 6) or to the amine oxides by the addition of peracetic acid (Examples 7 tolO).
The Table lists the percent of perfluoroalkylethyl-methacrylate monomer units (i), polyethoxylated nonylphenol methacrylate monomer units (ii) and N,N-diethylaminoethyl-methacrylate (DEAM) monomer units (iii) as either the free base, amine acetate or amine oxide present in the pol~er solids (15~) of the resulting terpolymer solutions.
TABLE

Fluoro-Example monomer Monomer Monomer DEAM
No. (i) (ii) (iii) Function 3 75 20 5 Free base 4 70 25 S Free base Amine acetate 6 70 25 5 Amine acetate 7 75 20 5 Amine oxide 8 70 25 S Amine oxide 9 70 20 10 Amine oxide Amine oxide

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A terpolymer comprising the following components:
(i) from 55 to 80 percent by weight of polymerized perfluoroaliphatic monomer of the formula RfQO2CC(R)=CH2 wherein Rf is a straight or branched-chain perfluoroalkyl group containing from 2 to 20 carbon atoms, R is H or CH3 Q is alkylene of 1 to 15 carbon atoms, hydroxy-alkylene of 3 to 15 carbon atoms, -CnH2n(OCqH2q)m-, -SO2NR1(CnH2n)- or -CONR1(CnH2n)-, R1 is H or C1-4 alkyl, n is 1 to 15, q is 2 to 4, and m is 1 to 15;
(ii) from 15 to 35 percent by weight of polymerized nonfluorinated polyethylene oxide acrylate or methacrylate monomer of the formula R2(OCH2CH2)pO2CC(R)=CH2 wherein R2 is C1-18alkyl, aryl or alkaryl containing 7 to to 24 carbon atoms, R is H or CH3, p is 10 to 50; and (iii) from 1 to 15 percent by weight of polymerized nonfluorinated monomer selected from the group CH2=C(R)CO2CH2CH2NR3R4, (CH2=C(R)CO2CH2CH2?R3R4R5)yX-Y, and ??

wherein R is H or CH3, R3 and R are C1-4 alkyl, R5 is H or C1-4alkyl, and X is an anion of valence y.

2. A terpolymer according to Claim l wherein component (iii) is polymerized CH2=C(R)CO2CH2CH2NR3R4 wherein R is H or CH3, and R and R4 are C1-4alkyl.

3. A terpolymer according to Claim 1 wherein component (iii) is polymerized (CH2 = C(R)CO2CH2CH2?R3R4R5)yX-Y
wherein R is H or CH3, R and R4 are C1-4alkyl, R5 is H or C1-4alkyl, and X is an anion of valence y.

4. A terpolymer according to Claim 1 wherein component (iii) is polymerized wherein R is H or CH3 and R3 and R are C1-4alkyl.

5. A terpolymer according to Claim 1 wherein component (i) is present in the amount of 68 to 78 percent by weight, component (ii) is present in the amount of 18 to 25 percent by weight, and component (iii) is present in the amount of 3 to 8 percent by weight.

6. A terpolymer according to Claim 2 wherein component (i) is present in the amount of 68 to 78 percent by weight, component (ii) is present in the amount of 18 to 25 percent by weight, and component (iii) is present in the amount of 3 to 8 percent by weight.

7. A terpolymer according to Claim 3 wherein component (i) is present in the amount of 68 to 78 percent by weight, component (ii) is present in the amount of 18 to 25 percent by weight, and component (iii) is present in the amount of 3 to 8 percent by weight.

8. A terpolymer according to Claim 4 wherein component (i) is present in the amount of 68 to 78 percent by weight, component (ii) is present in the amount of 18 to 25 percent by weight, and component (iii) is present in the amount of 3 to 8 percent by weight.

9. A terpolymer according to Claim 1 wherein component (i) is present in the amount of 75 percent by weight, component (ii) is present in the amount of 20 percent by weight, and component (iii) is present in the amount of 5 percent by weight.

10. A terpolymer according to Claim 2 wherein component (i) is present in the amount of 75 percent by weight, component (ii) is present in the amount of 20 percent by weight, and component (iii) is present in the amount of 5 percent by weight.

11. A terpolymer according to Claim 3 wherein component (i) is present in the amount of 75 percent by weight, component (ii) is present in the amount of 20 percent by weight, and component (iii) is present in the amount of 5 percent by weight.

1?. A terpolymer according to Claim 4 wherein component (i) is present in the amount of 75 percent by weight, component (ii) is present in the amount of 20 percent by weight, and component (iii) is present in the amount of 5 percent by weight.

13. A terpolymer according to Claim 12 wherein component (i) is polymerized RfCH2CH2O2CC(CH3)=CH2, wherein component (ii) is polymerized and wherein component (iii) is polymerized wherein Rf is a perfluoroalkyl group containing from 4 to 14 carbon atoms.