| abstract |
Graft polymers which contain N-vinyl units and in which the grafting base is a polymer which contains in each case at least 5% by weight of units of the formulae ##STR1## where R 1 and R 2 are each H or C 1 -C 6 -alkyl, monoethylenically unsaturated monomers are grafted onto the grafting base in a weight ratio of from 100:1 to 1:100, and which have K values of at least 7 (determined according to H. Fikentscher in 5% strength by weight aqueous solution at 25° C. and pH 7), are prepared by polymerization of monoethylenically unsaturated monomers in the presence of polymers which in each case contain at least 5% by weight of units of the formulae I and/or II as the grafting base in a weight ratio of from 100:1 to 1:100, and are used as dispersants for pigments, as additives for detergents and cleaning agents, and strength agents for paper and as soil stabilizers and for fertilizer compaction. |