Simultaneous enhancement of dielectric and thermal conductivity in poly(vinylidene fluoride) composite films via fluorinated graphene nanosheets incorporating

The thermal conductivity of dielectric polymers is expected to be improved by high thermal conductivity fillers to meet the demand for thermal management materials in high power electronics and integrated circuits. Though, graphene exhibits the remarkable thermal conductivity, its inherent electrical conductivity and the poor interfacial phonon coupling with the polymer matrix restrict its application as filler for the thermal conductive dielectric composites. Herein, we demonstrate fluorinated graphene (FG) as a dual-functional filler to overcome the graphene’s drawbacks of high electrical conductivity and poor interfacial compatibility, with its high thermal conductivity remaining. The results show that the interfacial thermal resistance between FG and matrix can be reduced through interfacial interaction. In addition, FG induces the in-plane orientation of poly(vinylidene fluoride) (PVDF) molecular chains to accelerate heat dissipation. The composite film with only 5 wt.% FG content exhibits extremely high thermal conductivity (6.8 W·m⁻¹·K⁻¹), which is 30 times higher than the pristine PVDF film. This work provides new ideas for fabricating thermally conductive dielectric composites, paving the way for next-generation dielectric thermal management materials in 5G/6G microelectronics.