Process for preparing acrylate-functional organopolysiloxane-urethane copolymers

Claim 1

A process for preparing radiation polymerizable acrylate-functional organopolysiloxane-urethane copolymers which comprises reacting an aminofunctional polysiloxane fluid having at least one unit of the formula ##STR13## where R is a divalent radical selected from the group consisting of a saturated divalent hydrocarbon radical having up to 20 carbon atoms, a divalent hydrocarbonoxy radical in which the oxygen atom is in the form of an ether linkage and an unsaturated divalent hydrocarbon radical having from 2 to 20 carbon atoms, R 1 is a monovalent hydrocarbon radical having from 1 to 20 carbon atoms, R 2 is a radical selected from the group consisting of a monovalent hydrocarbon radical having from 1 to 20 carbon atoms and a radical of the formula CH.sub.2 CH.sub.2 X, where X is selected from the group consisting of COOR 3 , CONR 3 , CN and SO 2 R 3 , R 3 is a monovalent hydrocarbon radical having from 1 to 20 carbon atoms, a is 0, 1 or 2, b is 1, 2 or 3, c is 1, 2, 3 or 4 and d is 0, 1, 2 or 3, with the proviso that c equals b-d+1 with an acrylated urethane oligomer in a mole ratio of acrylate groups to amine groups of from 0.75 to 10 in the presence of an organic solvent at a temperature of from 25° to 150° C., in which the acrylated urethane oligomer is obtained by reacting an organic compound having at least two active hydrogen groups with an excess of an organic polyisocyanate having at least two --NCO groups per molecule to form a urethane prepolymer having at least two --NCO groups per molecule and thereafter the --NCO containing prepolymer is reacted with a hydroxy-containing compound selected from the group consisting of an acrylic compound, a methacrylic compound, and an acrylamide compound in a mole ratio of --NCO group to OH group of from 0.5:1 to 1:0.5 at a temperature of from 25° to 150° C.