OPTIMIZATION OF THE ELECTRICAL-CONDUCTIVITY OF POLYPYRROLE FILMS ELECTROGENERATED ON ALUMINUM ELECTRODES

Polypyrrole films were electrogenerated by square-wave potentials, as homogeneous, adherent smooth layers, from NtBu p-CH3C6H4SO3 in acetoni trile solutions on aluminium electrodes. The conductivities of the obt ained films range from 10 to 350 S cm(-1) as a function of electrical and chemical variables of synthesis. The observed effects of the prepa ration conditions on the film conductivity are explained in terms of t he polymerization mechanism, in order to prepare high-quality films. T he evolution of the conductivity of these polymers as a function of th eir oxidation states has also been investigated. The conductivity chan ges from 10(-6) to 3 X 10(2) S cm(-1) when the polymer passes from a n eutral state to an oxidized state, by variation of the electrochemical potential from - 800 to 200 mV (versus SCE).