The phenyl thiyl radical as initiator in vinyl polymerizations. Investigations into the initiation step by the aminoxyl trapping technique

Abstract

The reactions of phenyl thiyl radicals with styrene, methyl methacrylate, methacrylonitrile, and vinylacetate in the presence of an aminoxyl radical scavenger have been studied. Two main products were formed: diphenyl disulfide, and the expected product formed by addition of the thiyl radical to the double bond of the monomer followed by trapping by the aminoxyl radical. The relative reactivity of the monomers towards addition of phenyl thiyl radicals at 60°C was: VA: MAN: MMA: STY = 1: 50: 100: 500.