A comparison of verdazyl radicals modified at the 3-position as mediators in the living radical polymerisation of styrene and n-butyl acrylate

Abstract

Four verdazyl radicals, with varying substituents at the 3-position, were synthesised and used to prepare unimolecular initiators for use in the stable free radical mediated living radical polymerisation of styrene and n-butyl acrylate. The addition of bulky substituents with differing electronic structures at the 3-position of the ring was investigated and the effects of these substituents on the properties of the verdazyl radical studied. The nature of the substituent was discovered to affect the rate and characteristics of polymerisation. The styrene and n-butyl acrylate homopolymers were chain extended to provide evidence of the verdazyl radical as the end group of the polymers.