Effect of surface treatment of nickel-coated graphite on conductive rubber

In the blended conductive rubbers, good dispersion of conductive fillers and great interfacial bonding with the substrate are the keys to achieving excellent mechanical and electromagnetic shielding properties. It is found that compared with octyltriethoxysilane (A137), 3-methacryloxypropyl-trimethoxysilane (A174) and vinyltriethoxysilane (A151) with a double bond reduce the curing degree of the blends. The vinyl methyl silicone rubber/nickel-coated graphite (VMQ/NCG) composites modified by A137 shows poor tensile properties, while the composites modified by A174 shows inferior electrical properties. The presence of physical adsorption and chemical adsorption on the surface of NCG modified by A151, which effectively enhances the dispersibility of NCG and interfacial bonding strength with rubber, so that the material exhibits excellent comprehensive properties. When the content of A151 is 3% and modified by dry method, the tensile strength of VMQ/NCG composites can reach 1.6 MPa, the elongation at break can reach 162%, and the volume resistivity can reach 0.05 Omega<middle dot>cm.