ELECTRODEPOSITION OF PROTECTIVE POLYANILINE FILMS ON MILD-STEEL

The electrodeposition of protective polyaniline (PANi) films on mild s teel from aqueous oxalic acid is reported. The electropolymerization o f aniline occurs on a surface passivated by the precipitation of an Fe (II)-oxalate layer and leads to strongly adherent films with a control led thickness and with the same structure as the idealized emeraldine base. When they are dipped in an acidic solution (0.4M NaCl+0.1M HCl) the PANi-coated iron samples exhibit very good protection against corr osion and are much more effective than polypyrrole coated ones.