Electrochemical synthesis of poly (aniline-co-o-anisidine) coatings on brass: corrosion protection properties

Abstract

Poly (aniline-co-o-anisidine) films were coated on Cu–40% brass electrodes using cyclic voltammetric conditions in a sodium oxalate solution with 0·06M aniline and 0·06M o-anisidine monomers at applied scan rates of 20 and 50 mV s−1. Using this procedure, the surface of the electrodes was clearly covered with a black copolymer layer of strongly adherent homogeneous characteristics. In order to evaluate the corrosion performance of copolymer coated (CuZn/PANI-co-POA) and uncoated electrodes in 3·5%NaCl, AC electrochemical impedance spectroscopy, anodic polarisation plots and open circuit potential–time curves were used. The copolymer films exhibited significant protection efficiency against the attack of corrosive agents and reduced drastically the corrosion rate of the brass.