Enhanced anticorrosive properties of tailored poly(aniline-anisidine)/chitosan/SiO2 composite for protection of mild steel in aggressive marine conditions

Present study focuses on the development of composite coating for corrosion protection of mild steel in marine environment. In the present work, in-situ chemical oxidative polymerization process is employed to synthesize poly(aniline-anisidine)/chitosan/SiO2 composite in aqueous medium of chitosan. The synthesized copolymer composites were characterized by FTIR, XRD, TGA, and SEM. Corrosion resistant coatings were developed by loading of the copolymer composites in the epoxy resin. Electrochemical behavior of coatings was studied in 3.5% NaCl for a span of 20 days. The electrochemical measurements have clearly demonstrated excellent improvement in the corrosion resistant properties of the substrate after application of coatings. Salt spray test (as per ASTM B117 standards) revealed that the composite coatings can withstand under accelerated corrosion conditions of high salt content and humidity for prolong periods. The improved corrosion resistance of the composite coatings is attributed to the effective combination of fillers (SiO2 nanoparticles), biopolymer (chitosan) in conducting matrix (poly(aniline-anisidine))