A comparative study on the effects of multi-walled carbon nanotubes and graphene nanoplates incorporated for improved thermal conductivity and dielectric properties of polyvinyl chloride

Abstract

In the present work, the improvement in the thermal conductivity and dielectric behavior in the frequency range of 0.025–5 MHz of polyvinyl chloride (PVC) films incorporated with graphene nanoplates (GNs) and multi-walled carbon nanotubes (CNTs) were investigated. The neat PVC and PVC composites consisting of different filler ratios of 0.25, 0.5, 0.75, and 1 wt% were synthesized using the casting technique. The increase in the concentration of GNs or CNTs up to 0.75 wt% enhanced the dielectric constant, ac conductivity, q-factor, F-factor, thermal conductivity, and total impedance of PVC composites. The values of the investigated parameters are slightly higher for PVC-CNTs composites compared to PVC-GNs composites. A further increase in concentration to 1 wt% reduces these parameters, but still more than PVC consisting of 0.5 wt% fillers. The mechanism of correlated barrier hopping (CBH) could be successfully used to describe the AC electrical conductivity of both PVC-GNs and PVC-CNTs composites thin films. Furthermore, the glass transition and decomposition temperatures were determined and found to be dependent on the filler ratio and type, and the thermal stability was increased after adding the GNs or CNTs nanofillers. These findings have drawn special attention to developing PVC composites that can be used in various industrial fields including flexible and wearable technologies, power devices, supercapacitors, electric vehicle battery systems, and aerospace components.