A study on the anticorrosion performance of epoxy nanocomposite coatings containing epoxy-silane treated nanoclay on mild steel in chloride environment

摘要

The halloysite nanoclay was chemically modified with different silanes such as 3-glycidoxypropyl trimethoxysilane (GPTMS) and 3-aminopropyl trimethoxysilane (APTMS) and examined by FTIR, TGA, and XRD techniques. The incorporation of functionalized nanoclay in the epoxy resin enhances the protectant properties of the coated steel. The anticorrosion properties were investigated by electrochemical measurements in chloride environment. The mild steel coated by epoxy-APTMS/clay nanocomposite displayed higher coating resistance (R-c=5407.88 k Omega cm(2)) in comparision with pure epoxy coating (R-c=549.51 k Omega cm(2)).The mechanical properties (hardness, adhesion strength and tensile strength) of the resultant nanocomposite were also evaluated. The introduction APTMS/clay (4 wt%) to the epoxy coating helps to increase the tensile strength to 80 MPa which is 25% higher than pure epoxy coating. The surface topographies of the studied coatings were investigated by SEM/EDX analysis. The results from electrochemical and mechanical investigations indicated that the as synthesized coatings consisting of epoxy-silanes/clay possessed an excellent adhesion, microhardness and corrosion protection properties.