Epoxy Polyaniline–SBA15/Fluconazole Hybrid Nanocomposite Coatings: As a Self-Healing Corrosion Protection of Mild Steel

The objective of this research is the production of an epoxy coating blended with organic–inorganic hybrid nanocomposite applied over mild steel, as a self-healing corrosion protection of defects. A series of conducting polyaniline (PANI)–SBA15/Fluconazole nanocomposites materials are being prepared by an in situ chemical oxidative method of aniline monomers in the presence of SBA15/fluconazole complex nanorods which were synthesized previously with camphor-sulfonic acid (CSA) and ammonium peroxydisulfate (APS) as surfactant and initiator, respectively. A commercial epoxy coating was applied over samples afterwards. The synthesized materials were characterized by X-ray diffraction pattern (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM). To determine the best inhibitor concentration, the anti-corrosion behavior of the Fluconazole was studied in a ammonium sulfide-sodium chloride pH 7 solution, at a temperature of 25 ͦ C using electro-chemical techniques including electrochemical impedance spectroscopy (EIS) and polarization potentiodynamic. The electrochemical results show that this inhibitor has an effect on anodic region forming a passivation layer, and the best result was achieved with 150 ppm of Fluconazole. The next step was to prepare the SBA15/Fluconazole nanorods, and finally the PANI-SBA15/Fluconazole composite, and evaluate the self-healing effect over mild steel. It was found that the presence of SBA15/Fluconazole nanorods dispersed in the PANI matrix can significantly improve the corrosion protection and barrier effect performance of the epoxy coating due to the flaky shaped structure of the PANI–SBA15/Fluconazole nanocomposites, evaluated electrochemically.