THE ROLE OF THE COUNTERION DURING ELECTROPOLYMERIZATION OF POLYPYRROLE CAMPHOR SULFONATE FILMS

The electrochemical preparation of polypyrrole-based films doped with camphor sulfonate which exhibit an anisotropic molecular organization is reported. The role of the dopant in determining the final structure of the film is explored by polymerization from electrolytes containin g mixed counter-ion species. Smaller counter-ion units are preferentia lly included in the growing polymer film at the expense of the bulkier camphor sulfonate units. The mechanism of electropolymerization is di scussed, particularly with reference to the interactions between the g rowing chain and the electrolyte which are dependent upon the hydropho bic/hydrophilic nature of the dopant.