Antimicrobial corrosion study of the epoxy coating with the graphene oxide supported Schiff base quaternary ammonium salt additives

In order to effectively inhibit microbial corrosion, the compounds of Schiff base quaternary ammonium salt (SQAS) and graphene oxide (GO) were used as filler added into the epoxy resin coating. The mechanical, hydrophobic and anti-microbial corrosion properties in simulated seawater of SQAS-GO inhibitor coating on carbon steel were investigated by grid test, contact angle test, electrochemical test and surface topography analysis, respectively. These results suggested that 0.5% SQAS-GO strengthened the anti-microbial corrosion performance of the epoxy resin coating. The electrochemical test results also demonstrated that the impedance value of the 0.5% SQAS-GO coating (6.31 ×1010 ohm cm2) was two orders of magnitude higher than that of the pure epoxy coating (1.09 ×108 ohm cm2) after being immersed in simulated seawater for 14 days. Moreover, molecular dynamics simulation of inhibitor provided the theoretical support for the experimental results.