Effect of graphene on the properties of epoxy in hygrothermal environment by molecular dynamics method

The physical and mechanical properties of graphene-reinforced epoxy (epoxy/graphene) in hygrothermal environment need to be comprehensively understood. This is because it is necessary to predict the durability of epoxy/graphene when epoxy/graphene is used in an aggressive environment with high humidity and high temperature. Based on the molecular dynamics method, the influences of water content (2, 4 and 6%) and temperature (298,333 and 368 K) on the physical and tensile properties of epoxy/graphene were studied in this research. The results showed that after the addition of graphene, the free volume fraction of epoxy and the diffusion coefficient of water molecules in the epoxy decreased, and the density, tensile strength and deformation performance of epoxy increased. In the hygrothermal environment, the tensile strength degradation rate of epoxy/graphene was lower than that of pure epoxy. The failure mechanism and mechanical response of epoxy/graphene during the tensile process in the nanoscale were revealed. The research results provide a reference for the design and performance optimization of epoxy/graphene composites in a hygrothermal environment.