Patent ID: 7238760

Claim:
A water-soluble or water-swellable copolymer containing sulfo groups and comprising a) from 3 to 96 mol % of units of formula I wherein R 1 is hydrogen or methyl; R 2 , R 3 , R 4 are independently selected from hydrogen, an aliphatic hydrocarbon radical having from 1 to 6 carbon atoms, a phenyl radical, or a phenyl radical substituted with methyl groups; M is hydrogen, a monvalent metal cation, a divalent metal cation, ammonium, or an organic amine radical; a is 0.5 or 1; b) from 3 to 96 mol % of units of at least one of formula IIa and IIb wherein W is —CO—, —CO—O—(CH 2 ) x —, or —CO—NR 2 —(CH 2 ) x —wherein x is from 1 to 6; R 5 and R 6 are independently selected from hydrogen, a C 1 -C 20 substituted aliphatic hydrocarbon radical, a C1-C20 unsubstituted aliphatic hydrocarbon radical, a C5-C8 cycloaliphatic hydrocarbon radical, a C6-C14 aryl radical; and Q is hydrogen or —CHR 5 R 7 ; R 7 is hydrogen, an aliphatic hydrocarbon radical having from 1 to 4 carbon atoms; —COOH or —COO—M a , and R 1 , R 2 , M and a are as defined above; wherein if Q is not hydrogen, R 5 and R 6 in IIb can together form a —CH 2 —(CH 2 ) y -methylene group where y is from 1 to 4; c) from 0.05 to 75 mol % of units of at least one of formulas IIIa and IIIb wherein Y is O, NH or NR 5 ; V is —(CH2) x —, R 8 is R 5 , R 6 , —(CH 2 ) x —SO 3 − (M), and X is halogen, a C 1 -C 4 -alkyl sulfate or a C 1 -C 4 -alkylsulfonate; R 1 , R 2 , R 3 , R 5 , R 6 , and x are as defined above; and d) from 0.01 to 30 mol % of units of formula IV wherein Z is —COO(C m H 2m O) n —R 9 , —(CH 2 ) p —O (C m H 2m O) n —R 9 , wherein R 9 is a saturated or unsaturated, linear or branched, aliphatic hydrocarbon radical having from 22 to 40 carbon atoms, or R 10 is H, C 1 -C 4 -alkyl-, phenyl-, benzyl-, C 1 -C 4 -alkoxy, halogen, cyano, —COOH, —COOR 5 , —CO—NH 2 , or —OCOR 5 ; R 11 is an arylalkyl group having a C 1 -C 12 -alkyl radical and a C 6 -C 14 -aryl radical; m is from 2 to 4; n is from 0 to 200; p is from 0 to 20; and R 1 and R 5 are as defined above, wherein the copolymer is water-soluble or water swellable and contains sulfo groups.