Radiation-induced network formation in polyvinyl chloride polyfunctional monomer systems

Some aspects of the radiation polymerization of allylic polyfunctional monomers in mixtures with polyvinyl chloride have been investigated. The process proceeds through a stepwise formation of the network polymerizate from the polyfunctional monomer, reaction between the polymerizate and polyvinyl chloride and further crosslinking of polyvinyl chloride through reaction with residual allylic double bonds. The initiating radical for the first stage is a low-molecular weight radiolytic product of polyvinyl chloride (apparently, the chloro-radical). At higher initial monomer content the structure formed changes from that of a crosslinked copolymer to that of an interpenetrating network, during irradiation. In the presence of aliphatic plasticizer, the crosslinking density increases in irradiated compositions of polyvinyl chloride and polyfunctional monomers. Copyright (C) 1996 Elsevier Science Ltd.