TETRAPHENYLETHANE INIFERTERS - 8 - DIPHENYLMETHANE DIISOCYANATE-BASEDPOLYURETHANE INIFERTER FOR LIVING RADICAL POLYMERIZATION OF METHYL-METHACRYLATE

A novel polyurethane iniferter, synthesized from equal moles of 4,4'-d iphenylmethane diisocyanate and 1,1,2,2-tetraphenyl-1,2-ethanediol was used to polymerize methyl methacrylate. The rate equation and overall activation energy have been determined using kinetic results. As the polymerization time and conversion increased, molecular weight of the polymethyl methacrylate also increased. Postpolymerization of polymeth yl methacrylate in the presence of methyl methacrylate and styrene yie lds high molecular weight polymethyl methacrylate homopolymers and pol ymethyl methacrylate-polystyrene block copolymers respectively. Hence, the present polyurethane iniferter acts as a thermal iniferter and fo llows ''living'' radical polymerization. (C) 1997 Elsevier Science Ltd .