Effects of graphene surface morphology on damping properties of epoxy composites

Abstract

In nature, a rougher surface is usually accompanied by a higher friction coefficient, providing greater friction with the objects in contact. The higher surface roughness of nanofillers dispersed in the matrix might improve the energy dissipation capacity of composites. For a better understanding of the mechanism of different damping enhancement capabilities of graphene, comparative studies on composites reinforced with two types of graphene are carried out to evaluate the factors such as surface roughness, friction, dispersion, and the specific surface area. Reduced graphene oxide (rGO) and graphene oxide (GO) are selected as reinforcement, where the composites are fabricated and the damping properties are tested. The results indicate that adding rGO/GO can significantly increase the damping ratios of composites. The damping ratios of composites reinforced with 0.3% weight ratio rGO and GO increase to 3.01% and 4.13% from 2.27% for pure resin, respectively, which indicates that GO has superior damping enhancing capability. The mechanism of graphene surface wrinkles for increasing the friction force induced higher damping capacity is analyzed on the microscopic scale. The influencing factors studied in this paper shed light on the subsequent selection of graphene with high damping enhancement capabilities.