Electrosynthesis and protection role of polyaniline-polvinylalcohol composite on stainless steel

Polyaniline-polyvinyl alcohol (PANI-PVA) composite has been electrodeposited on stainless steel surface from aqueous sulfuric acid solution of aniline monomer in presence of soluble PVA at different concentrations. The PVA increased the rate of electropolymerization where 4 g/L PVA formed a composite of 37 wt% PANI and 63 wt% PVA composition. The composite layer exhibited more adhesion to the steel surface in comparison with PANI layer but with less thermal stability. It has higher protection role for the stainless steel (SS) against general and pitting corrosion. It enhanced the passivation of the SS surface by increasing the thickness of oxide film and improving the composition.