Construction of functionalized graphene nanoplatelets/SiC nanowires hybrid skeleton for epoxy composites with enhanced thermal conductivity and thermomechanical properties

Functionalized graphene nanoplatelets/SiC nanowires (f-GnP/SiCnw) and unmodified (u-GnP/SiCnw) hybrid skeletons with different amounts of SiCnw were successfully constructed through a vacuum-assisted self-assembly technique. Subsequently, the hybrid skeletons were incorporated into an epoxy resin to fabricate nanocomposites with excellent thermal and thermomechanical properties. The study revealed that the f-GnP/SiCnw hybrid skeletons exhibit a more pronounced reinforcing effect than the f-GnP-only skeleton without SiCnw and the unmodified (u-GnP/SiCnw) counterparts at the same filler loading. Incorporating the f-GnP/SiCnw hybrid skeleton with 5 wt% SiCnw resulted in through-plane and in-plane thermal conductivity of the epoxy composites as high as 1.58 W/m·K and 6.20 W/m·K, which is 690 and 3000% higher than that of the neat epoxy, respectively. Meanwhile, the storage modulus and glass transition temperature of the epoxy composites were also evidently enhanced after the introduction of the hybrid skeletons. This work provides an insight into the fabrication of high-performance thermally conductive composites.