Abstract
Aniline was electropolymerized using constant-potential electrolysis. The chronoamperograms during the electropolymerization definitely had two different time dependences on the electrolytic current. During the initial stage, the current increased with the square root of the electrolysis time, and then increased linearly with the time. Those results were intrinsically the same as those of the electrodeposition of metal ions. To determine the kinetic parameters, the electrolytic current during the polymerization was analyzed on the basis of metal electrodeposition models developed by Fleishmann and Thirsk. The rate constant of the polymerization reaction was found to be directly proportional to the concentration of protons, to the concentration of anions and to the square of the concentration of aniline; also, the rate constant was formulated using the concentrations as well as the electrolysis potential and temperature. The concentration dependence of the rate constant led to the belief that the rate-determining reaction in the polymerization was the electro-oxidation of the dimer of aniline, p-aminodiphenylamine.
