Polymerization of N‐vinylcarbazole, 3. Studies of copolymerizations with methyl methacrylate and styrene

Copolymers of N‐vinylcarbazole (VCZ) with methyl methacrylate (MMA) and styrene (ST) were prepared using doubly‐labelled benzoyl peroxide as initiator and the relative numbers of benzoyloxy and phenyl end‐groups were determined. In the copolymers containing MMA, the ratios of the two types of end‐group are those expected for products of free radical polymerization. The copolymers of VCZ with ST contain benzoyloxy and phenyl end‐groups in proportions which correspond to those found in homopolymers of VCZ made in non‐radical polymerizations promoted by the peroxide.