Constructing bi-functional Ce-MOF on carbon fiber endowing epoxy coating with excellent anti-corrosion and erosion wear resistance

The limited interfacial combination between CF and polymer matrix caused by the chemical inertness of CF surface greatly restricts the protective capability of carbon fiber reinforced polymer coatings (CFRPCs), which could not effectively resist the impact of external forces, especially in the severe and complicated ocean environment (like deep-sea area and splash zone). Hence, it is the crux to enhance the interface compatibility and interface strength between fiber and resin. Based on the reliable compatibility between imidazole and epoxy as well as the corrosion inhibition effects of cerium-based compounds, a kind of bi-functional metal-organic framework (MOF) called the cerium-imidazole framework (Ce-MI) was constructed on the CFs surface via in-situ growth method to improve the interface compatibility and interface strength of fiber and resin and further increase protective performance of epoxy (EP) coating under the simulated deep-sea area and splash zone. After 168 h immersion under alternating hydrostatic pressure, CF@Ce-MI/EP coating displayed impressive impermeability and anti-corrosion performance, and the interfaces of fiber/epoxy adhered firmly. After the erosion wear test, the volume loss and mass loss of CF@Ce-MI/EP were decreased by 23.77% and 14.80%, respectively, compared with CF/EP. Finally, we discussed the protective mechanism of composite coating to reveal the different processes of interface failure caused by the high pressure and the impact of solid particles, respectively.