Electrodeposition of Polypyrrole Films on 2024 Aluminum Alloy in Phosphoric Acid Solution

Polypyrrole was synthesized onto aluminum surfaces by electrochemical polymerization technique using pyrrole monomer and phosphoric acid in aqueous medium. The influence of applied potential on the morphology of the films was studied by Scanning electron microscopy (SEM). The films displayed a cauliflower-like structure consisting of micro-spherical grains. This structure is related to dopant intercalation in the polymeric chain. The efficiency of these polymeric films to protecting aluminum alloy against corrosion was investigated by potentiodynamic polarization curves. It was also observed that the polymer roughness depend on the applied potential.