Effect of polymer modifier chain length on thermal conductive property of polyamide 6/graphene nanocomposites

The influence of polymer modifier chain length on the thermal conductivity of polyamide 6/graphene (GA) nanocomposites, including through-plane (λz) and in-plane (λx) directions were investigated. Here, three chain lengths of double amino-terminated polyethylene glycol (NH2-PEG-NH2) were used to covalently functionalize graphene with graphene content of 5.0 wt%. Results showed that λz was enhanced with the chain length of NH2-PEG-NH2 increased, but λx reached a maximum value at a certain chain length of NH2-PEG-NH2. The maximum λz and λx of GA are 0.406 W m−1 K−1 and 9.710 W m−1 K−1, respectively. This study serves as a foundation for further research on the thermal conductive property of graphene nanocomposites using different chain lengths of polymer modifier to improve the λz and λx of the thermal conductive materials.