Preparation and Corrosion Resistance of Pani/Ppy Composite Films on Sliver Surface

Polyaniline/polypyrrole (Pani/Ppy) composite films were prepared on the surface of silver by chemical oxidation using ferric chloride as oxidant, aniline and pyrrole as matrix. The surface morphology, thermodynamic stability and corrosion resistance of the composite films were investigated by infrared spectroscopy (IR), thermogravimetry (TG), scanning electron microscopy (SEM), electrochemical polarization analysis and self-corrosion potential-time analysis. The results show that the thermal decomposition temperature of composite membrane with n(Ani)/n(Py) of 1/3 was 450℃, which could meet the requirements in application at the operating temperature range of 20-300℃. The composite films had obvious anti-corrosion effect on the silver flake. The anti-corrosion effect of the composite film with n(Ani)/n(Py) of 1/3 was the best.