Multifunctional poly(vinylidene fluoride) nanocomposites via incorporation of ionic liquid coated carbon nanotubes

Abstract In this work, simultaneously enhanced thermal conductivity, heat dissipation and dielectric constant of poly(vinylidene fluoride) (PVDF) were prepared by adding ionic liquid (IL)-coated carbon nanotubes (IL@CNTs). IL@CNTs and common CNTs were melt-compounded with PVDF to prepare the composites, respectively. The results clearly demonstrated that IL@CNTs exhibited better dispersion and higher ability to form the percolated network structure. Studying on crystallization behaviors showed that IL@CNTs not only exhibited better nucleation effect on PVDF crystallization but also induced a large number of the polar β/γ-form crystallites formation in the composites. Thermal properties measurements showed that IL@CNTs exhibited more apparent role in enhancing the thermal conductivity of the composites. Specifically, IL@CNT endowed the composite sample with higher heat dissipation ability compared with the common CNTs during the cooling process. In addition, the largely enhanced dielectric constant was also achieved for the PVDF/IL@CNT composites. The mechanisms were analyzed and suggested to be mainly related to the improved dispersion and denser percolated network structure of IL@CNTs in the composites, the improved interfacial interaction between fillers and matrix, and the varied crystalline structure of the PVDF matrix. The prepared composites have great potential application as the heat management material of the flexible electronic devices.