Preparation of aqueous polymer dispersions

Abstract

Aqueous polymer dispersions are prepared by free radical polymerization of (a) from 50 to 100%, based on the total weight of the monomers, of C.sub.1 -C.sub.20 -alkyl (meth)acrylates, (b) from 0 to 20%, based on the total weight of the monomers, of polyolefinically unsaturated monomers and (c) from 0 to 30%, based on the total weight of the monomers, of further monoolefinically unsaturated monomers in aqueous emulsion in the presence of a preformed solution copolymer (A) dispersed in water and obtained from (I) 1.5-15%, based on its weight, of monomers of 3 to 10 carbon atoms which contain a carboxyl or carboxylic anhydride group, (II) 30-98.5%, based on its weight, of C.sub.1 -C.sub.20 -alkyl acrylates or methacrylates, (III) 0-60%, based on its weight, of vinylaromatics, (IV) 0-20%, based on its weight, of monoolefinically unsaturated carbonyl compounds and (V) 0-20%, based on its weight, of further monomers not stated under (I) to (IV) and a solution copolymer (B) obtained from 40-100%, based on its weight, of monomers (II) and 0-60%, based on its weight, of monomers (III) to (V).

Dependencies are inferred from the claim text.