Silane-Modified MXene Nanosheets for Improved Anticorrosive Properties of Epoxy Coatings: A Combined Experimental and Computational Study

Ti3C2Tx (MXene) nanosheets have been widely noticed and investigated by researchers as a strategy to enhance the anticorrosive properties of epoxy resin (EP) coatings, but their proclivity to accumulate and poor compatibility with the resin matrix limit their further application. In this paper, MXene was modified using a simple one-pot synthesis with (3-glycidoxypropyl)trimethoxysilane as a surface modifier, and EP composite anticorrosive coatings were prepared using MXene and modified MXene (M-MX) as fillers. Compared with MXene, M-MX has better dispersion in the coating, which can effectively enhance the anticorrosive property of the coating. Among all of the coatings, the composite coating containing 1 wt % M-MX showed the best anticorrosive effect after immersion in a 3.5 wt % NaCl solution for 21 days. The results of salt spray testing and corrosion product analysis indicated that the trend of the corrosion resistance of different coatings was EP < 0.5M-MX < 1MX < 2M-MX < 1M-MX. According to the results of density functional theory and molecular dynamics calculations, all nanosheets were able to block the corrosive medium in the epoxy coatings. Also, M-MX dispersed more uniformly in the composite coatings, which made the system more compact, prolonged the penetration paths of the corrosive medium, slowed down the diffusion of the corrosive medium, and thus provided the coatings with more excellent corrosion resistance properties.