An investigation on the corrosion behavior of the epoxy coating embedded with mesoporous silica nanocontainer loaded by sulfamethazine inhibitor

In this study, mesoporous silica served as the host for an eco-friendly corrosion inhibitor. This material could adsorb and release corrosion inhibitor in different aqueous media. A composite coating was prepared by embedding 1 wt. % mesoporous silica loaded with sulfamethazine (MSInh) as the corrosion inhibitor into the epoxy film to protect mild steel as substrate. Anti-corrosion properties of the solution containing MSInh and corrosion protection function of composite coating were assessed by electrochemical impedance spectroscopy. Results showed the higher corrosion protection of epoxy/mesoporous silica loaded with inhibitor (MSInh) in NaCl solution for one month of immersion in comparison with epoxy/mesoporous silica and epoxy coatings. Charge transfer resistance of epoxy, epoxy/MS, and epoxy/MSInh after 30 days of immersion estimated 6, 15, and 80 k Omega cm(2) , respectively. The results revealed the higher corrosion resistance of epoxy/MSInh which confirmed the barrier effect of mesoporous silica against corrosive species and corrosion inhibiting effect of the released sulfamethazine molecules.