▎ 摘　　要

The power density of electronic devices has been progressively increased in the last years, thus raising the urgent demand for the efficient systems of electrical conductivity. In a sense a promising strategy to increase the electrical conductivity of polymer composites is to construct interconnected three-dimensional graphene nanoplatelets networks. Due to the variety commercialized graphene nanoplatelets, some researchers have reported the need to incorporate higher concentrations. This research aims to develop nanocomposites with electrical conductivity potential, based on high concentrations of graphene nanoplatelets (i.e., 12.5 and 25 wt%) and conventional polymers (i.e., polystyrene (PS) and acrylonitrile butadiene styrene (ABS)). Moreover, it will investigate the effects of the high concentrations of graphene nanoplatelets on the mechanical, rheological and morphological properties of the nanocomposites. The results showed that the graphene nanoplatelets directly interfere in the complex viscosity and in the dynamic-mechanical properties of the polymers matrices. A significant increase in volume electrical conductivity was verified in both polymeric matrices when graphene nanoplatelets were added. While polymeric matrices acted as insulating materials, the nanocomposites containing 25 wt% of graphene nanoplatelets acted as semiconductors, for both matrices (PS and ABS). However, the mechanical properties of the tensile strength and impact were strongly reduced, due to the increased stiffness of the nanocomposites. These results indicated a potential application of these nanocomposites with high contents of graphene nanoplatelets in the electronics field, possibly as an alternative to conventional semiconductor materials, provided that the required mechanical properties are of low performance. [GRAPHICS]