Enhanced thermal conductive property of polyamide composites by low mass fraction of covalently grafted graphene nanoribbons

High thermal conductive polyamide-6 (PA6) composites based on graphene nanoribbons (GNR) were prepared by an in situ polymerization process and thermal reduction progress. The covalently grafted GNR structures allowed for significantly reducing the number of thermal contacts between GNR layers, leading to the more efficient percolating thermal paths in polymer matrix. As a result, the thermal conductive property of the PA6/GNR composites was significantly improved at a relatively low GNR loading. At GNR mass fraction of only 0.5 wt%, 165% and 95% enhancement of the thermal conductivity of the composites in in-plane and through-plane directions, respectively, was obtained.