Novel anticorrosive coating of silicone acrylic resin modified by graphene oxide and polyaniline

Abstract

Abstract Coatings of metal surfaces is a convenient and low cost anti-corrosion issue, while corresponding defects like poor heat and corrosion resistance are also obviously hinder its further application. Hence, continuously developing new and efficient coatings is of great significance to improve anti-corrosion for metals. In this study, silicone-acrylic resin was modified by two-dimensional lamellar structure of graphene oxide (GO) though direct co-blending to improve the anti-corrosion. Then, polyaniline/graphene oxide (PANI/GO) composites was prepared by in-situ polymerization method, which innovatively achieved the combination of flake and fibrous materials to fill the voids generated when the coating is cured into a film, and enhance the density and the anti-corrosion performance of the coating. The result showed that the coating modified by PANI/GO had the better thermal stability, which T 5% and T max are increased by 44 and 5 °C, respectively. Electrochemical impedance spectroscopy (EIS) and Tafel polarization curves were employed to analyze anticorrosion performance of modified coatings explored in 3.5 wt% NaCl aqueous solution. The coating with 20 wt% GO in PANI/GO has the best corrosion resistance with corrosion potential of −0.14 (V vs. Hg/Hg2Cl2), corrosion current density of 1.8 × 10−11 A cm−2, polarization resistance of 6.06 × 1010 Ω cm2, and lower corrosion rate of 4.18 × 10−7 mm year−1 after immersion for 60 day.