Corrosion resistance of polyaniline coatings formed by electropolymerization on titanium grade 2

Conductive polymer coatings due to their ease of synthesis and chemical and electrical properties are the focus of attention. In this research, polyaniline coating formed on commercial titanium substrate with current density of 10, 20, 30 and 40 m A /cm2 by electropolymerisation. The morphology and surface structural were analyzed by scanning electron microscopy (SEM). For investigation of chemical bonds, samples were studied by Fourier transformation infrared spectroscopy analysis (FTIR). The corrosion resistance was evaluated by potentiodynamic polarization and electrochemical impedance. SEM results showed the formation of polyaniline coating with Cauliflower structure. The average grain size of coating was about 1 micron. The results showed that a uniform polyaniline coating was formed on the surface of titanium substrate. The FTIR results confirmed the formation of polyaniline coating on the titanium substrate. Applying a polyaniline coating with current density of 30 mA /cm2 reduced corrosion current density up to 217 times in sodium in 3.5% chloride solution.