Abstract: Self crosslinking polyurethane comprising lateral or terminal ethenylarylene groups, produced by reacting a polyurethane pre-polymer with an adduct, obtained by reacting an ethenylarylene mono-isocyanate with a compound containing hydroxyl groups or amino groups such that at least one group that is reactive to isocyanate remains in the adduct. Also, a self crosslinking graft copolymer containing at least one (meth)acrylate copolymer and at least one polyurethane produced by dispersing at least one self crosslinking olefinically unsaturated polyurethane comprising lateral or terminal ethenylarylene groups and blocked isocyanate groups in an aqueous medium and by radical copolymerization of a mixture of a monomer comprising at least one functional group that is reactive to isocyanate with a monomer that can be copolymerised with the mixture.