Fabrication of pristine graphene-based conductive polystyrene composites towards high performance and light-weight

Although highly electrically conductive polymer composites filled with two-dimensional graphene-based nanofillers have been considerably explored, it still remains a challenge for constructing these nanocomposites with high filler efficiency, mild fabricating condition, as well as more effective conductive network at lower nanofiller contents. To meet above objectives, a facile preparation strategy was designed, wherein the pristine graphene (pGR) was utilized as nanofiller in polystyrene (PS) particle matrix via latex technology. Owing to the absence of reduction process, the hot-processing parameters were optimized to be more gentle ones. The structural, morphological, electrical, thermal and mechanical properties of resultant PS/pGR nanocomposites with various pGR contents were systematically investigated. SEM and TEM images showed the excellent interfacial adhesion between these two materials and segregated conductive structure was well-established. The as-fabricated PS/pGR composites achieved a quite high electrical conductivity of 20.5 S/m at a relatively low pGR loading of 0.957 vol% and an ultralow electrical percolation threshold of 0.0475 vol%. The thermal conductivity (TC) increased by 2.1 times at 0.957 vol% pGR loading than neat PS and the mechanical properties also exhibited applaudable results. This novel strategy to fabricate high performance PS conductive composites based on pristine graphene as nanofillers was thus proved to be effective.