Enhanced Thermal Conductivity of Segregated Poly(vinylidene fluoride) Composites via Forming Hybrid Conductive Network of Boron Nitride and Carbon Nanotubes

This work placed an emphasis that constructing segregated boron nitride (BN)/carbon nanotube (CNT) hybrid network brought an immense benefit to enhance the thermal conductivity (TC) of poly(vinylidene fluoride) (PVDF) composites. The segregated composites ((CNT + BN)@PVDF) showed a high TC of 1.8 W/mK at the total filler fraction of 25 vol %, outperforming PVDF composites with random structure (CNT/BN/PVDF) and segregated BN structure (BN@PVDF) by 169% and 50%, respectively. Infrared thermal images further demonstrated that (CNT + BN)@PVDF exhibited superior capability to dissipate heat compared to BN/PVDF. The segregated architecture increased the effective utilization of fillers and interfacial thermal resistance between neighboring BN platelets was reduced by the bridging effect of CNTs. Molding pressure and temperature governed the integration of segregated networks and thus the enhancement efficiency of TC. The design of hybrid segregated structure holds promise in a broad range of the preparation of thermal management materials.