Aqueous emulsions of polymer resin systems employed in water-based paint and coating compositions, comprising as a component thereof conferring enhanced wet adhesion properties, a reactable monomer corresponding to the structural formula ##STR28## wherein R is hydrogen or methyl, U designates a cyclic or acylic ureido or thioureido group and L designates CH.sub.2 or a linking chain containing in said chain at least one moiety from the group consisting of oxygen, amido, amino, and carbonyl, provided that any carbonyl group present is not directly attached to U or to an ethylenic carbon atom nor is an ethylenic carbon directly attached to a nitrogen atom, said reactable monomer being polymerized into said polymer resin system.