Dramatically improving the interfacial adhesion of CF/epoxy composite through synergistic deposition of silver nanoparticles and polydopamine

Strengthening the interfacial bonding between fibers and matrixes has been a relevant topic in the development of high-performance carbon fiber (CF)-reinforced polymer composites. To accomplish this goal, a new design strategy for hierarchical reinforcement was developed. Taking advantage of the excellent adhesion and reductive capability of polydopamine (PDA), we propose a green and facile method for attaching silver nanoparticles (AgNPs) to the CF surfaces, establishing the hierarchical structure of CF-PDA@Ag. The success of our approach was confirmed by the substantial differences in the morphological and chemical characteristics, wettability, and monofilament tensile strength of the CFs before and after the co-grafting with PDA and AgNPs. The CF-PDA@Ag/epoxy composite shows effective enhancements of 51.5 %, 41.3 %, and 50.9 %, in the interlaminar shear strength (ILSS), flexural strength, and flexural modulus, respectively. The mechanism of interface enhancement was also analyzed.