Liquid Silicone Rubber as Secondary Matrix in Epoxy/Graphene Nano-Platelets (GNP) Conductive Materials

Graphene nanoplatelets (GNPs) were employed as conductive fillers in an epoxy/liquid silicone rubber (LSR) system, with a range of filler loadings from 5 vol.% to 20 vol.%. An investigation was carried out to assess the mechanical, electrical, and thermal stability properties. At low GNP loading (0.2 vol.%), a notable enhancement in the toughness of epoxy/LSR/GNP system was observed. At high GNP loading (0.8 vol.%), the toughness and flexural properties were slightly reduced, but there was a dramatic increase in electrical conductivity. The epoxy system with 5 vol.% of LSR and 0.8 vol.% of GNP had better mechanical properties but lower electrical conductivity compared to the epoxy system with 20 vol.% of LSR and 0.8 vol.% of GNP. Moreover, the epoxy/LSR/GNP system exhibited superior thermal stability compared to the pure epoxy. The incorporation of GNP nano-fillers in the epoxy/LSR system resulted in an improvement in mechanical, thermal, and electrical properties.