An Anomalous Cathode-Initiated Copolymerization of Styrene and Methyl Methacrylate on the Electrode

The cathode-initiated copolymerization of styrene and methyl methacrylate (MMA) in dimethylformamide yielded a copolymer which was found to be a mixture of the high and low molecular weight copolymers. The composition of the former, rich in MMA, was similar to that of a typical anionic copolymer. The latter, of anomalously high styrene content, was assumed to be produced on the cathodic surface via an anionic process, where styrene monomer was preferentially adsorbed. This was confirmed by capacitance measurement of the electrode and sequence analysis of the copolymer.