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.