Extended protection of mild steel in saline and acidic environment using stearic acid grafted chitosan preloaded with mesoporous-hydrophobic silica (mhSiO2)

Abstract

This study produces an enhanced anti-corrosion property of chitosan-based film on mild steel (MS) in different aggressive media using surface modified SiO2. Mesoporous hydrophilic SiO2 is rendered hydrophobic by using silylating agent hexamethyl disilazane (HMDS). The incorporation of 3.0 weight percentage surface-modified silica into the chitosan matrix and further grafting with stearic acid (SA) through 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) mediated coupling reaction improve the anti-corrosion properties of the coating on mild steel. The resulting chitosan-based film was characterized by FTIR, TGA, AFM, FESEM, and EDX techniques. The film formed was applied for corrosion protection of mild steel in 0.5 M HCl and 3.5% NaCl and analyzed via non-electrochemical and electrochemical techniques.