Patent ID: 8318882

Claim:
An anionic modified copolymer obtained by polymerization of the monomers (A), (B) and (C) to obtain a nonionic copolymer having reactive terminal OH groups and conversion of the terminal OH groups to anionic end groups, wherein the anionic end groups are radicals SO 3 M, CH 2 COOM, PO 3 M 2 or sulfosuccinate, where M is H, a monovalent metal cation, a divalent metal cation, NH 4 + , a secondary, tertiary ammonium ion, quaternary ammonium ion or a combination thereof, (A) is a monomer of formula (I) wherein A is C 2 - to C 4 -alkylene, B is a C 2 - to C 4 -alkylene other than A, k equals 0 or 1, m is from 0 to 500, n is from 0 to 500, provided the sum total of m+n is from 1 to 1000; wherein the monomer (B) is a compound of formula (IIa) or (IIb): wherein X a is an aromatic or araliphatic radical having 3 to 30 carbon atoms, optionally containing one or more of the heteroatoms N, O or S, Z a is H or (C 1 -C 4 )-alkyl, Z b is H or (C 1 -C 4 )-alkyl, Z c is H or (C 1 -C 4 )-alkyl; wherein R 1 is hydrogen or methyl, X b is an aromatic or araliphatic radical having 3 to 30 carbon atoms, optionally containing one or more of the heteroatoms N, O or S, W a is oxygen or the NH; and wherein the monomer (C) is a compound of formula (IIIa) or formula (IIIb): wherein R 2 is hydrogen or methyl, Y is an aliphatic hydrocarbyl radical having 1 to 30 carbon atoms, which optionally is linear or branched or cyclic, and optionally contains the heteroatoms O, N, S, or a combination thereof or optionally is unsaturated, W b is oxygen or the NH; wherein R 3 is an aliphatic hydrocarbyl radical having 1 to 30 carbon atoms, which optionally is linear or branched or cyclic, and optionally contains the heteroatoms O, N, S or a combination thereof or is optionally unsaturated.