DE2733788A1 - SURFACE-ACTIVE MIXED POLYMERISATES - Google Patents

Description

PATENT LAWYERS

Dr. Iny. by Kreislui \ 1973

Dr.-Iny. K. Schünwuld, Cologne

Dr.-III'j. TIi. Mcyei, Cologne

Dr.-Iny. K.W. Lishold, Bud Soden

Di. J. F. Fucs, Cologne

Dipl. Cliem. Aluk from Kreislui, Cologne

Dipl.-Cliciii. Curolci Kl-IIci, Cologne

Di |) l.-Imj. G. Sillintj, Cologne

5 Cologne ι · ^{26 J} uly 1977

DH (J \ t;,;. NNI IAUb AM

AvK / IM

The B.F. Goodrich Company, Akron, Ohio, USA

Surface-active copolymers

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Phone; (0321) 234541 - 4 · Tele «'. 882307 dopa d K-kyromm: Dompoicnt Cologne

Polymeric surfactants are known. However, polymeric surfactants have good emulsifying properties and at the same time, when dissolved in water, maintain a high surface tension preserved, not easily manufactured and available.

Copolymers and tripolymers of unsaturated carboxylic acids and long chain esters are useful as water thickeners in U.S. Patent 3,915,592. These copolymers of a carboxylic acid monomer and one or more Alkyl acrylate esters containing 1o to 3o carbon atoms serve as thickeners in solutions, even in the presence of substantial amounts of inorganic salts such as sodium chloride.

The invention relates to new and improved water-soluble surface-active copolymers which are excellent Have emulsifying activity, while unexpectedly leading to the high surface tension of the aqueous solution contribute. These new copolymers are obtained by adding 2o to 6o% by weight of an alkyl acrylate ester in which the alkyl groups contain 8-3o carbon atoms, with 80 to 40 wt .-% of an olefinically unsaturated carboxylic acid and optionally with 0 to 15% by weight of a copolymerizable, an olefinically unsaturated sulfonic acid containing monomers and 25 to 8o wt .-% of said carboxylic acid monomer in the presence of the molecular weight modifying agents copolymerized as chain transfer or terminating agents. Be there Copolymers with molecular weights of less than 10,000 and their salts are obtained.

The polymers according to the invention are made from at least two essential monomers prepared in certain proportions for each, one monomer being a monomeric olefinic unsaturated carboxylic acid and the other monomer is an acrylic acid ester having a long-chain aliphatic group

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are. The monomer mixture optionally comprises a further monomer, which is a copolymerizable sulfonic acid contains.

The carboxylic acid monomers suitable for the purpose of producing the copolymers according to the invention are olefinically unsaturated carboxylic acids which contain at least one activated olefinic carbon-carbon double bond and at least one carboxyl group, ie an acid which contains an olefinic double bond which reacts easily during the polymerization, v Because it is either in the • • (-ß position, based on the carboxyl group, in the monomer molecule, ie it contains the formula -C = C-COOH, or it is present as part of a terminal methylene group of the formula CH ₂ = C _n The direct proximity of the strongly polar carboxyl group has a strong activating effect on the "^ -ß-unsaturated acids, so that compounds containing this structure are very easily polymerizable. Olefinically unsaturated acids of this class include compounds as diverse as acrylic acids, for example acrylic acid itself, methacrylic acid, ethacrylic acid, A-chloroacrylic acid,. ^ - Cyanoacrylic acid, ß-methylacrylic acid (crotonic acid), Λ-phenylacrylic acid, ß-acryloxypropionic acid, sorbic acid, -chlorosorbic acid, angelic acid, cinnamic acid, p-chlorocinnamic acid, ß-styryl acrylic acid (1-carboxy-1-phenylbutadiene-1,3) , Citraconic acid, mesaconic acid, glutaconic acid, aconitic acid, maleic acid, fumaric acid and tricarboxyethylene. The term "carboxylic acids" used here includes the polycarboxylic acids and their acid anhydrides, such as maleic anhydride. Maleic anhydride and the other acid anhydrides useful herein have the general formula

R-C-

Il

R ¹ - C -

^X 0

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in which R and R ^{1 are selected} from hydrogen , halogen, cyanogen (- C = N), hydroxyl, lactam and lactone groups and alkyl, aryl, alkaryl, aralkyl and cycloalkyl groups such as methyl, ethyl, propyl, Acrylic, Decyl, Phenyl, ToIy1, Xylyl, Benzyl and Cyclohexyl existing group are selected.

The preferred carboxylic acid monomers for the purposes of the present invention are monoolefinic acrylic acids the general formula

R CH ₂ = C-COOH

in which R is a substituent selected from the following class of compounds: hydrogen, halogen, Hydroxyl, lactone, lactam and cyanogen (-C = N) groups, monovalent alkyl radicals, monovalent aryl radicals, monovalent Aralkyl, monovalent alkaryl and monovalent cycloaliphatic Leftovers. From this class, acrylic acid and alkacrylic acids such as methacrylic acid are particularly preferred because of their generally low cost, ready availability, and ability to form superior polymers. Another particularly preferred carboxylic acid monomer is

2o maleic anhydride.

The preferred acrylic ester monomers with long chain aliphatic radicals are derivatives of acrylic acid represented by the formula

R ¹ 0 CH ₂ = C -COR

in which R represents an alkyl radical having 8-3o, preferably 10 to 22 carbon atoms, and R ^{1 is} a hydrogen atom or an alkyl radical having 1 to 3 carbon atoms. Representative higher alkyl acrylic acid esters are decyl acrylate, lauryl acrylate, stearyl acrylate, behenyl acrylate and melissyl acrylate and the corresponding methacrylates. Mixtures of two or three or more long chain

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Acrylic acid esters can be successfully polymerized with one of the carboxylic acid monomers. Other vinylidene monomers, for example those which have at least one terminal H ₂ C _N group, can also be used, as long as they do not have any adverse effect on the desired properties of the copolymers.

The monomer mixtures of the carboxylic acid monomers and the Long chain acrylic acid ester monomers preferably contain 95 to 5o wt .-% carboxylic acid monomer and 5 to 5o Wt% acrylic acid ester monomer.

The copolymerizable comonomers containing an olefinically unsaturated sulfonic acid preferably have at least one terminal ethylenically unsaturated group and one sulfonic acid group. By introducing the Sulphonic acid group in the polymer has been found that such emulsifiers from these copolymers even are even more effective at very low pH values such as 2 and below. Typical monomers that have a sulfonic acid group Bring into the polymers include 2-acrylamido-2-methylpropanesulfonic acid, Ethylene sulfonic acid, alkyl sulfonic acids, styrene sulfonic acid, 2-sulfoethyl methacrylate and their precursors. These monomers are used in amounts from 0 to about 15 weight percent, including some replace the carboxylic acid monomers.

It should be noted that these polymeric emulsifier dispersants are essentially free of crosslinking since they lose their effectiveness when crosslinked are or are in gel form or are of high molecular weight, in which case they are essentially

3o are ineffective as surfactants.

The low molecular weight copolymers of acrylic acid and long-chain alkyl methacrylates, which are preferably also contain an olefinically unsaturated sulfonic acid polymerized, are in salt form, neutralized with an

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- * ■ 2733'88

organic or organic base to form substantially water soluble materials capable of initiating and promoting emulsion polymerization of vinylidene monomers. Vinylidene monomers, of course, include those monomers which _{contain at least one terminal vinylidene group CH 2} \ and are well known to those skilled in the art. The use of the surfactants, particularly if they contain a sulfonic acid group, allows use at extremely low pH or aids in such polymerization approaches. The emulsifying dispersants have a number of other uses, e.g., they can be used to unexpectedly produce high surface tension latices that result in dried polymer deposits therefrom with improved water resistance and substrate adhesion when compared to conventional emulsifiers. These emulsifying dispersants can also be added as post-polymerization latex stabilizers in order to contribute to a higher surface tension of the latices.

2o apply.

It is believed that the formulations of the typical surfactants, i.e. the copolymers according to the invention, which have the general formula below, in which "a" is a long-chain alkyl methacrylate such as isodecyl methacrylate, lauryl methacrylate, tridecyl methacrylate and stearyl methacrylate and a number from about 3o to 5o, "b" is acrylic acid or methacrylic acid and is a number from about 10 to 6o and "c" is from 0 to about 40 and / is a sulfonic acid containing monomer which typically comprises 2-acrylamido-2-methylpropanesulfonic acid or sodium vinyl sulfonate.

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The copolymers according to the invention are easy produced by polymerization in an inert diluent that has a certain dissolving effect on a or more of the monomeric components, but preferably a slight dissolving effect on the obtained Polymer exerts. Bulk polymerization can be used but is not preferred because of the difficulties the work-up of the solid polymer masses obtained. Polymerization in an aqueous medium that Contains a water-soluble, free radical-forming peroxy catalyst, is appropriate, the product either as precipitated granules or as a highly swollen gel is obtained and both forms either Can be used directly or can be easily further divided and dried. Polymerization in one organic liquid that is a solvent for the monomers but a nonsolvent for the polymer or a mixture of such solvents in the presence of a water soluble catalyst is most preferred, since the product is usually obtained as a very fine, easy to grind and often flaky precipitate which after removal of the solvent seldom requires grinding or crushing or other treatments before the Requires use. Suitable solvents for the latter method include benzene, xylene, tetralin,

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Hexane, heptane, carbon tetrachloride, methyl chloride, ethyl chloride, bromotrichloromethane, dimethyl carbonate, diethyl carbonate, Ethylene dichloride and mixtures of these and other solvents.

The polymerizations can also be carried out in the presence of a haloethane or halomethane, which preferably contains at least 4 halogen atoms. Representative Compounds are, for example, a fluoroethane, fluoromethane, chlorofluoromethane, bromofluoroethane, or preferably a Chlorofluoroethane or chlorofluoromethane with at least 4 Halogen atoms such as 1,1,2-trichloro-i, 2,2-trifluoroethane, Trichlorofluoromethane, tetrafluoromethane, chlorotrifluoromethane, Bromotrifluoromethane, 1-chloro-1,1,2,2,2-pentafluoroethane, Dichlorodifluoromethane, and 1,2-difluoro-1,1,2,2-tetrachloroethane. The amount of these materials can be varied to just be enough to make a slurry of the reactants to give up to a substantial excess of the chlorofluoroethanes, as would be known to those skilled in the art is known. Preferred diluents are those that are solvents for the monomers but nonsolvents for the polymers are.

To have molecular weights of the copolymer emulsifiers averaging less than 10,000, usually less than 5000 on average and in an even more preferred range. from 500 to 3500 are chain termination or chain transfer agent required. These are also called molecular weight modifiers Means. Generally, these materials are of two types.

The first type of the molecular weight modifying agents are mercaptans containing from about 6 to about 2O carbon atoms, preferably about 8 to about 16 carbon atoms and, for example, dodecyl mercaptan, tertiary C ₁₂ ~ ^Merca P include ^tan d ^un similar alkyl mercaptans.

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Other known chain transfer agents include halogenated compounds, thiuram disulfide, dialkylxanthogen disulfide, diaryldisdfides, and substituted phosphines. The desired molecular weight can also be obtained by using solvents which have chain terminating activity such as isopropanol and carbon tetrachloride. Combinations of these molecular weight modifiers can also be used. The amount of the molecular weight modifying compound is chosen so that a polymer having a molecular weight below about 10,000 is obtained, which can be easily determined. Quantities of 0.1 to 10% by weight, based on the monomers, or even larger quantities of the solvents modifying the polymers are contemplated. 1 to 5% alkyl mercaptan is preferred.

The polymerization in a dilute medium is carried out in the presence of a free radical forming catalyst a closed vessel in an inert atmosphere and under self-pressure or artificially applied pressure or carried out in an open vessel under reflux at atmospheric pressure. The temperatures of the polymerization can vary from 0 to 100 ° C. and depend to a large extent on the desired molecular weight of the polymer.

Polymerization under reflux at 50 to 90 ° C under atmospheric conditions Pressure using a free radical forming catalyst is generally effective Polymer yields from 75 to 100% in less than 10 hours to surrender. Typical free radical forming catalysts include peroxygen compounds, e.g. sodium, potassium and ammonium persulfates, caprylyl peroxide, benzoyl peroxide, hydrogen peroxide, pelargonyl peroxide, cumene hydroperoxides, t-butyl diperphthalate, t-butyl perbenzoate, t-butyl peroxypivalate, Sodium peracetate and sodium percarbonate and also azodiisobutyronitrile, hereinafter referred to as azoisobutyronitrile and other compounds known to those skilled in the art of polymerization. The polymers obtained

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are neutralized with an inorganic or organic base. For example with monovalent alkali such as sodium, potassium, lithium or ammonium hydroxide or their carbonates and bicarbonates or their mixtures and also basic amines, which are no more than one primary or have secondary amino group. Polyvalent bases such as calcium hydroxide, magnesium hydroxide and others Hydroxides of group HA of the periodic table can be used. Other organic bases such as triethanolamine, Morpholine, dicyclohexylamine, dipropylamine and triethylamine and tertiary amines can be used.

example 1

40 parts by weight of dodecyl methacrylate, 60 parts by weight of acrylic acid, 3.9 parts by weight of t-dodeayl mercaptan, 0.35 parts by weight

Caprylyl peroxide and 1125 parts by weight of Freon 113, CF ₂ ClCFCl ₂ were placed in a pressure vessel and heated to 65 ° C. for 15 hours, whereby the conversion to the polymer was essentially complete. The obtained polymer had a number average molecular weight based on

End group sulfur analysis of 7000 + 1000. The copolymer was isolated from the freon, dried and dissolved in distilled water containing 0.6% ammonium hydroxide, to get a 1% solution. This polymeric emulsifier solution then became water in various amounts given and the surface tension of the solution was according to ASTM D1.331 measured and compared with that of solutions of polar oligomers with terminal alkyl sulfide groups (US-PS 3 839 4o5) and sodium lauryl sulfate. The results are as follows:

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-V * r

Table I. Alkylsul- Sodium lauryl Concentr. Lauryl methacrylate fidoligo- sul fat ' in water lat / acrylic acid mere dyn / cm % dyn / cm dyn / cm 72.0 72.0 0,000 72.0 61.4 47.3 0.0025 72.0 59.8 33.0 0.0074 72.0 55.0 3S.0 0.014 70.9 53.0 31.0 0.024 70.9 47.0 29.4 O.C-11 69.9 42.4 29.3 0.061 68.0 41.0 26.6 0.079 67.9 40.0 27.9 0.112 64. 7 40.0 28.2 0.140 61.0 39.1 31.2 0.164 61.0 39.0 31.0 0.136 61.0 39.0 31.5 0.204 61.0 39.2 32.4 0.222 61.0 39.7 32.2 0.250 61.0

In addition, the surface tension of a water / mineral oil intermediate phase was determined measured according to ASTM D971-5o. The received Results are as follows:

Table II Alkylsul- Sodium lauryl Concentr. Lauryl methacrylate fidoligo- sulfate in water lat / acrylic acid mere dyn / cm % dyn / cm dyn / cm 3 7.2 37.2 0.00 37.2 27. S. 16.5 0.0025 30.4 10.5 12.4 0.0074 ? 2.i 3.2 3.9 0.014 25.3 2.3 4.7 0.024 25.9 2.8 4.9 0.041 17.8 2.8 4.6 0.061 18.7 2.2 5.9 0.097 17.9 2.9 5.1 0.127 15.8

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/ IS

Example 2

In this polymerization, the chain terminator isopropanol was also used as the polymerization medium and 40 parts by weight of dodecylin ethacrylate, 60 parts by weight of acrylic acid and 0.35 parts by weight of caprylyl peroxide were dissolved in 100 parts by weight of isopropanol. This mixture was in an autoclave held at 65 ° C. for 15 hours. Substantially complete conversion was obtained. Alternatively, to recover the solvent-swollen solid, ammonia was bubbled through the solution and the solid was separated by centrifugation and drying.

Example 3

Example 2 was made with 1.0 parts by weight of t-dodecyl mercaptan repeated with similar results.

Example 4

In this experiment 40 parts by weight of dodecyl methacrylate, 0.3 parts by weight of caprylyl peroxide and Given 25o parts by weight isopropanol. A water solution of 15 parts by weight of 2-acrylylamido-2methylpropanesulfonic acid was then added to this mixture. 45 parts by weight of acrylic acid and 35 parts by weight of deionized water. The mixture was heated to 65 ° C for 6 hours. The received Solids was 28.9% and the conversion was greater than 97%. The polymer was isolated by passing ammonia through it the solution bubbled, centrifuged and dried.

Example 5

Three other copolymers were made according to Example 1 as follows set out produced:

(1) 40 parts by weight of lauryl methacrylate, 60 parts by weight of acrylic acid and 4.25 parts by weight of t-dodecyl mercaptan. A 1% Solution of the salt of this polymer in water had a Brookfild viscosity of Ho Cps at 60 rpm with a rotor

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No. 2.

(2) Another copolymer was made according to Example 2 in isopropanol with 40 parts by weight of lauryl methacrylate and 6o parts by weight of acrylic acid. An 8.5% Solution in water had a Brookfield viscosity of 75 cps at 60 rpm with a # 1 rotor.

(3) 40 parts by weight of lauryl methacrylate, 15 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid and 45 parts by weight Acrylic acid were converted into isopropanol. A solution of 7% total solids of the ammonium salt in water had a Brookfield viscosity of 10 cps at 60 rpm with a No. 1 rotor.

(4) 40 parts by weight of isodecyl methacrylate, 15 parts by weight 2-Acrylamido-2-methylpropanesulfonic acid and 45 parts by weight of acrylic acid were reacted in isopropanol. A 1o% Solution of the ammonium salt in water had a Brookfield viscosity of 26 cps at 60 rpm with a # 1 rotor.

Example 6

A 1.5% solution of the copolymers 2, 3 and 4 from Example 5 together with sodium lauryl sulfate solutions, a naphthalene dispersant (naphthalene sulfonic acid condensed with formaldehyde) and polyacrylic acid and used to saturate bleached 0.28 mm thick paper, which is then stored at 1o5 ° C for 72 hours has been heat aged for a long time. The samples were tested by aging at 0, 6, 24, 48 and 72 hours the change in light reflection measured with a model 61o photovoltmeter was read. the Data are given in the table below:

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87 86 86 86 85 85 81 63 53 43 88 81 76 74 71 87 81 77 75 72 88 82 77 74 72 88 86 81 74 62

Heat aging light reading of the reflectlon

Hours 0 6 24 48 72

Control paper (Bleached Kraft) 5 naphthalene dispersants

Emulsifier 2
Emulsifier 3
Emulsifier 4
Sodium lauryl sulfate
Polyacrylic acid - Daxad 3o 87 75 69 67 66

The extraordinary resistance to ultraviolet discoloration of the paper with the emulsifiers mentioned was saturated as compared to the naphthalene type dispersants is clearly stated. These types of dispersants are widely used in latex polymerization approaches that are used in paper saturation for a a large number of different end uses can be used. 2 1 / 2x4 inch paper samples were used for testing in the Fade-Ometer made. The samples were taken from the fade ometer after 2o, 4o, 6o and 8o hours of aging removed.

The photovolt reflection was measured at each time interval and the sample was placed back in the fade-ometer, until she was exposed to UV light for 80 hours. The fade-meter reflectance values are in the following

25 table indicated:

Ultraviolet light aging reflectance values

Hours of control paper 3o naphthalene dispersant 60

Emulsifier 2 3 4

20th 40 60 80 82 82 82 82 60 55 55 55 82 82 82 82 82 82 82 82 82 82 82 82

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It

Example 7

To enable the use of surfactants in Showing emulsion polymerizations became a series of reactions carried out using the following standard recipes. All ingredients are in parts by weight per 100 parts of monomer. the Polymerization was carried out at 70-80 ° C for about 2 hours.

distilled water sodium lauryl sulfate Polymer # 4

Ethyl acrylate Acrylonitrile Ammonium persulfate

100 100 1.5 .1.5

97

3 0.5

100 1.5

97

0.5

100 100

1.5

1.5

97 97

3 3

0.5 0.5

The following test results were obtained with the latices obtained:

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% Coagulum

% Total Solids Brookfield Viscosity at 60 RPM 12 RPM (K / Oo

Particle size in X shear force; Waring mixer Viscosity at 60 rpm

1 min.

3 min.

5 min.

0.35
48.2 0
48.7 0.25
47.2 0.80
47.9 2.5
46.9 85 cps
140 cps
4,519 ",
4920 A 13 5 cps
300 cps
0.2919,
1285 A '5 0 cps
65 cps
5,223
5282 27 cps
3 5 CDS
4.02 5
• IG49 12 cps
11 ccs
4,935
5137 105 cps
780
1260 Coagulate
Coagulate 37 cps
175
640 23
105
540 92
420

■ <] co

SO

The shear stability of the latices obtained was tested in a Waring mixer at 17,500 rpm. The three latices those with the surface-active agents according to the invention all had better shear stability than the latex made with sodium lauryl sulfate was produced. The surface-active copolymer with 40 parts by weight of isodecyl methacrylate, 45 parts by weight Acrylic acid and 15 parts by weight of 2-acrylamido-2-methylpropanesulfonic acid had outstanding shear stability.

The polymeric surface-active agents, i.e. the copolymers manufactured according to the invention as described preferably have a Brookfield viscosity in water substantially equivalent to that of a 1% solution of the ammonium salt of less than 300, preferably less than 200 cps at 60 rpm with a # 2 rotor.

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Claims (17)

Claims Copolymers containing about 2o to 60 wt .-% of an acrylic acid ester monomer of the formula R ₁ 0 CH ₂ = C -COR in which R is an alkyl radical with 1o to 3o carbon atoms and R. is a hydrogen atom or an alkyl radical with 1-4 Carbon atoms, and 4t> to 80% by weight of an olefinic unsaturated carboxylic acid monomers having a molecular weight less than about 10,000. 2. Copolymers according to claim 1, wherein R _{1 is} a hydrogen atom or a methyl radical and R is an alkyl radical having 10 to 16 carbon atoms. 3. Copolymers according to Claims 1 and 2, wherein the olefinically unsaturated carboxylic acid monomer contains a terminal methylene group CH ₂ = C ^. 4. Copolymers according to claims 1-3, wherein the carboxylic acid monomer has the formula CH ₂ = C-COOH in which R _{2 is} a hydrogen atom, a halogen atom or a monovalent alkyl radical having 1 to 4 carbon atoms. 5. Copolymers according to claims 1-4, wherein in said acrylate ester R _{2 is} a hydrogen atom or a methyl radical and R is a monoalkyl radical having 10 to 12 carbon atoms. 709886/0731 OAtQlNAL INSPECTED 6. Copolymers according to claims 1-5, wherein the carboxylic acid monomer is acrylic acid and the copolymer has a molecular weight below 5000. 7. Copolymers according to claims 1-6 in the form of a water-soluble salt. 8. Copolymers according to claims 1-7, wherein the salt of an inorganic monovalent alkali metal or is derived from an amine having 1-6 carbon atoms. 9. Copolymers according to Claims 1-8 in the form of an ammonia salt. 10. Copolymers according to claims 1-9, wherein the acrylic ester monomer is lauryl methacrylate. 11. Copolymers according to claims 1 - 1o from 2o to 6o wt .-% of an acrylic acid ester monomer of the formula R ₁ 0
CH ₂ = C -COR in which R is an alkyl radical with 1o to 3o carbon atoms and R _{1 is} a hydrogen atom or an alkyl radical with 1 to 4 carbon atoms, and 25 to 80% by weight of an olefinically unsaturated carboxylic acid monomer and 0 to 15% by weight of an olefinically unsaturated sulfonic acid containing Comonomers where the molecular weight is less than about 10,000. 12. Copolymers according to claims 1-11, wherein the carboxylic acid monomer is acrylic acid and the acrylic acid ester monomer is dodecyl or lauryl methacrylate and that Copolymer has a molecular weight below 50,000. 13. Copolymers according to claims 1-12, wherein the sulfonic acid monomer is 2-acrylamido-2-propanesulfonic acid. 709886/0731 14. Copolymers according to claims 1-13, wherein R is an alkyl radical having 10 to 14 carbon atoms and R _{1 is} a hydrogen atom or a methyl radical. 15. Copolymers according to claims 1-14, wherein the acrylic acid ester monomer is dodecyl methacrylate, the carboxylic acid monomer is acrylic acid and the sulfonic acid monomer is 2-acrylamido-2-propanesulfonic acid and the copolymer
has a molecular weight below about 5000. 16. Use of the copolymers according to claims 1-15 in the aqueous emulsion polymerization of vinylidene monomers with a free radical forming catalyst and a chain terminator. 17. Use of the copolymers according to claims 1-15 in an aqueous dispersion of a polymer of
at least one vinylidene monomer. 709886/0731