Processing and Mechanical Properties Investigation of Epoxy-Impregnated Graphene Paper

One-layer (0.15 mm thick) and 15-layer (5.43 mm thick) graphene composites have been fabricated through the impregnation of epoxy resin into porous graphene nanoplatelet (GnP) paper. Three different flake sizes of GnPs were used for the 1-layer graphene composites: 5 mu m, mixed 5 mu m and 25 mu m, and 25 mu m. The largest graphene flakes showed the best material properties in terms of tensile strength and elongation at break. Both tensile and DMA test results demonstrated that the 15-layer graphene composite had better material properties than the 1-layer graphene composites. The storage modulus of 15-layer graphene composite was 170% higher than that of neat epoxy. The transverse surface of 15-layer graphene composite exhibited a higher elastic modulus but lower hardness than the top surface. Ballistic limit test results showed that the combination of polyurea (PU) and a 15-layer graphene composite coating can increase the ballistic limit of TC-128 steel plate slightly.