KINETICS OF POLYPYRROLE AND POLYTHIOPHENE ELECTROGENERATION FOLLOWED BY MICROGRAVIMETRY

The kinetics of polypyrrole and polythiophene electrogeneration were followed by microgravimetry. The generation of polypyrrole from water solutions depends of [ClO4-]0.8 and [pyrrole]0.5. When acetonitrile solutions were used, both reactions orders were 0.5. The empirical kinetics of the polythiophene generation was dependent of [ClO4-] and [thiophene]. The water content influence on the kinetics was followed in a solution of pyrrole in acetonitrile. The different behaviour of both monomers, using a rotating disk electrode, and when the temperature of polymerization was modified, along with the great influence of the electrolyte on the kinetics, lead us towards a complex electrodic mechanism. A general model of interfacial reactions is proposed, able to explain the experimental results and to suggest new hypothesis of work.