THE CATIONIC POLYMERIZATION OF N-VINYL-2-PYRROLIDONE INITIATED ELECTROCHEMICALLY BY ANODIC POLARIZATION ON A PT SURFACE

The electroinitiated polymerization of N-vinyl-2-pyrrolidone has been investigated. After electrolysis at controlled potential, a thin, cove ring, and homogeneous film of poly (N-vinyl-2-pyrrolidone) appears on the electrode. The insolubility of the polymer in its classical solven ts implies the existence of a true chemical grafting of macromolecules on the platinum surface. Chain propagation occurs by a cationic mecha nism initiated by a direct electron transfer leading to grafted cation s on the surface, followed by the nucleophilic attack of neutral molec ules. The molecular weight of the polymer was estimated by gel permeat ion chromatography after having mechanically removed the film from the electrode. A molecular weight distribution curve showing an average v alue of 16,000 was observed. (C) 1994 John Wiley & Sons, Inc.