Thermal and mechanical behavior of graphene loaded synthetic graphite/polyphenylene sulfide (PPS) composites

Thermoplastics when they become thermally conductive, have a great potential to be used in thermal management applications due to their low cost, lightweight, and flexibility. Here, synthetic graphite and graphene are used as thermally conductive fillers to fabricate Polyphenylene Sulfide- (PPS) based composite materials with high thermal conductivity. Graphene and graphite added PPS composites were manufactured by using a twinscrew extruder and injection molding machine. Physical, thermal, mechanical, and morphological properties of the composites were investigated by several characterization methods including thermogravimetric analysis, differential scanning calorimetry, thermomechanical analysis, scanning electron microscopy, thermal diffusivity measurement, and tensile and flexural tests, The in-plane and through-plane thermal conductivity coefficient of graphene (5 wt. %) loaded synthetic graphite (40 wt. %)/PPS composites are greatly improved to 26.45 and 5.02 W/mK, respectively compared to that of neat PPS. The outstanding in-plane thermal conductivity of graphene loaded graphite/PPS composites is attributed to the formation of an effective thermal conductive pathway due to the alignment of the layered structure of graphene and graphite fillers in the flow direction.