Patent ID: 6846882

Claim:
A process for modifying polymers containing acid groups by reaction of (a) polymers comprising at least 5% by weight of a copolymerized monoethylenically unsaturated monomer containing acid groups and having molar masses of from 200 to 100,000 with (b) polyalkylene glycols which are end-capped at one end, alkylpolyalkylene glycol amines or mixtures thereof, or mixtures of at least one of the two compounds specified with up to 30% by weight, based on the mixtures, of ammonia, amines, alcohols, hydroxycarboxylic acids or aminocarboxylic acids at up to 250° C., wherein the polymers used as component (a) are ones which are obtained by free-radical polymerization of monoethylenically unsaturated acids in aqueous solution in the presence or absence of other monoethylenically unsaturated monomers and in the presence of at least 4% by weight, based on the monomers used in the polymerization, of a water-soluble sulfur compound in which the sulfur is in the oxidation state +4.