ELECTROCATALYTIC BEHAVIOR OF A POLY(N-METHYLANILINE) FILMED ELECTRODETO HYDROQUINONE

Poly(N-methylaniline) (PNMA) was prepared on a bare platinum electrode by electrooxidation of N-methylaniline in 1.0 mol dm(-3) HCl. The PNM A film was more stable to anodic treatment than the polyaniline film. The electric conductivity of the PNMA film was potential dependent. Hi gh conductivity appeared only within the potential region where PNMA i tself was redox-active. The PNMA filmed electrode showed redox respons e to dissolved hydroquinone whose redox current was evident within the potential region. Furthermore, the PNMA film behaved as an electrocat alyst for the electrode reaction of hydroquinone. The kinetics of the electrocatalytic reaction were investigated mainly using a rotating di sc electrode. The experimental results obtained were analysed by the t heory of Albery and Hillman, and the rate constant of the electron cro ss-exchange transfer between hydroquinone and the redox-active sites i n the film (k) was determined and found to be 6.4 x 10(3) M(-1) s(-1) at 20 degrees C.