PYRROLE COPOLYMERIZATION AND POLYMER DERIVATIZATION STUDIED BY X-RAY PHOTOELECTRON-SPECTROSCOPY

Nitro-functionalized polypyrrole films have been deposited on gold surfaces by copolymerization with pyrrole or by derivatization of the polymer. Electrochemical copolymerization of 2- and 4-nitrostyrenes or 2- and 4-nitrobenzaldehydes with pyrrole indicates that lower polymerization yields result from the 2-nitro aromatics due to steric factors. Copolymerization of pyrrole in the presence of 2- or 4-nitrotoluene or isomeric chloronitrotoluenes does not incorporate the nitroaromatics into the polypyrrole matrix, but does affect the oxidation state of the resulting polymer. N-Arylation of N-acylation of preformed polypyrrole films were performed using 2,4-dinitrofluorobenzene, 4-nitrobenzoyl chloride, or 5-nitro-2-furoyl chloride. Electropolymerization of (2,2'-dipyrrolyl)(nitrophenyl)methanes were also performed for comparison purposes. X-ray photoelectron spectroscopic analysis of the derivatized polymers shows that the nitro substituents exhibit varying degrees of stability toward oxidation, reduction, and aging.