Electrodeposition of Polypyrrole on Aluminium in Oxalic Acid

Adherent and homogenous polypyrrole films were electropolymerized onto aluminum from aqueous oxalic acid and oxalic acid containing different anions ( SO3^2-, SO4^2-, CO3^2- DBS-,) by cyclic voltametry. The corrosion behavior of coated and uncoated aluminum with polypyrrole wasinvestigated in 0.1 M HCI by potentiodynamic polarization method. Inhibition effect of anions ontouncoated aluminum was determined in 0.1 M HCI. The curves of anodic and cathodic polarizationwere obtained. The electrochemical parameters were determined from the polarization curves. Theefficiency of polypyrrole coating on aluminum was calculated. It was shown that thin PPy film hadprovided good corrosion protection of aluminum in 0.1 M HCI. Oxalate|DBS-|, PPy system had showed the most superior corrosion protection properties than other anion systems.