Abstract:
The expanded graphene was stripped by physical and mechanical stripping method, and the nano graphene sheets (GE) with thickness of 10 nm and horizontal size of 10-20 μm were obtained, and the GE/natural rubber (NR) concentrated masterbatch with mass fraction of 20wt% was further prepared. The hydrophobic SiO
2 was obtained by modifying the precipitated SiO
2 with the silane coupling agent KH580. The GE-SiO
2/NR composites which contain 0, 0.2wt%, 0.5wt%, 1.0wt% and 2.0wt% GE were prepared by mechanical blending. By testing the conductive and thermal conductivity of the GE-SiO
2/NR composites, it is found that its thermal and electrical conductivity gradually improve with the increase of GE content. When the GE content is 2.0wt%, the thermal conductivity in pane increases by 38.1%, the thermal conductivity through pane increases by 36.21% and the electrical conductivity increases by 36.07%. The higher the GE content, the greater the 100% and 300% tensile stress of the GE-SiO
2/NR composites, but the change of tensile strength, tearing strength and breaking elongation are not obvious. With the increase of GE content, the network effect of filler and Payane effect are weakened, and the glass temperature gradually increases. According to the SEM analysis, the modified SiO
2 is well dispersed in the NR matrix without agglomeration. When the GE content is 2.0wt%, the lamellar structure of GE is obviously observed.