Silk Fibroin-CF Hybrid Nanofiller Endowing Epoxy Coating with Outstanding Anticorrosion and Anti-erosion Properties

The exceptional protective coating can extend the service life of the equipment in a severe marine environment. Carbon fibers (CFs), characterized by high tensile strength, elastic modulus, and excellent chemical resistance, serve as an appropriate filler for coating reinforcement. However, the inadequate fiber/matrix interfacial adhesion makes it difficult to prepare high performance CF-reinforced composites. Therefore, we synthesized a kind of silk fibroin modified CF (CF─SF) as a reinforced-additive for strengthening the corrosion resistance and anti-erosion properties via improving the interfacial adhesion between CFs and resin matrix. The impedance value of composite coating including 1 wt% CF—SF (CF—SF/EP) was 1.65 × 108 Ωˑcm² after immersion, which was two orders of magnitude greater than that of the pure EP coating. In addition, the erosion experiments results showed that the volume loss of EP/CF—SF coating was 132.6 mm³, which decreased by 36.4% and 17.4% compared with EP/CF and EP/CF─O, respectively. The average depth of the CF—SF/EP coating (0.27 mm) was the shallowest among the coatings. Ultimately, we examined the protective mechanism of the CF–SF/EP coating.