GROWTH OF 2-LAYER AND COPOLYMER POLYOXYPHENYLENE COATINGS - AN ELECTROCHEMICAL AND XPS INVESTIGATION

The growth of polyoxyphenylene coatings consisting of either a single copolymer layer or two homopolymer layers has been studied by electroc hemical and x-ray photoelectron spectroscopy techniques. The compositi on of the coatings near the outer (coating/electrolyte) and inner (met al/coating) surfaces has been compared with the following results: (i) the inner face of copolymer coatings is enriched in the faster diffus ing monomer; (ii) the inner and outer surfaces of coatings obtained by successive electrolyses of two different monomers are enriched in the second and first monomer, respectively. These results agree with a gr owth mechanism involving polymerization at the metal/coating interface controlled by monomer diffusion.