Comparison of anticorrosion behavior of polyaniline and poly(3,4-methylenedioxyaniline) and their titanium dioxide nanocomposites

Abstract

In this study, polyaniline (PANI) and poly(3,4-methylenedioxyaniline) (P(MDAN)) nanocomposites with titanium dioxide (TiO2) nanoparticles were investigated on Al1050 electrodes. Aniline (ANI), MDAN, ANI/TiO2, and MDAN/TiO2 nanocomposites were successfully electropolymerized by the chronoamperometric method. The modified films were characterized by different techniques such as scanning electron microscopy (SEM), Fourier transform infrared–attenuated transmission reflectance, and electrochemical impedance spectroscopy (EIS). The surfaces of modified electrodes were observed by SEM and an optical microscope with a camera. Anticorrosion behaviors of PANI, PANI/TiO2, P(MDAN), and P(MDAN)/TiO2 films were measured in 3.5% sodium chloride solution by Tafel extrapolation and EIS techniques. PANI, PANI/TiO2, P(MDAN), and P(MDAN)/TiO2 film electrodes increased the corrosion resistance of the film as compared to the uncoated Al1050 substrate. Therefore, the highest protection efficiency of 97.2% was obtained for PANI/TiO2 film. The corrosion resistance values of PANI, PANI/TiO2, P(MDAN), and P(MDAN)/TiO2 films were increased significantly compared with the uncoated Al1050 electrode.