Impact of BaTiO3 as Insulative Ferroelectric Barrier on the Broadband Dielectric Properties of MWCNT/PVDF Nanocomposites

摘要

This study was devoted to investigating the effects of BaTiO3 incorporation on the broadband dielectric properties of melt-mixed multi-walled carbon nanotube/poly(vinylidene fluoride) (MWCNT/PVDF) nanocomposites. BaTiO3, as insulative barrier, was incorporated into the composites with MWCNT loadings close to and above the percolation threshold, where conductive networks were unstable and newly formed. The results showed that BaTiO3 did not create any change in the volume resistivity and percolation curve; nevertheless, it reduced the dissipation factor considerably. For instance, at 100 Hz the dissipation factor of the MWCNT/PVDF nanocomposite was 130, which dropped to 48 and 0.45 by adding 1.0 and 3.0 vol% BaTiO3, respectively. It was also observed that incorporating BaTiO3 muted the descending trends of dielectric permittivity and dielectric loss with frequency, confirming the role of BaTiO3 as insulative barrier. The positive impact of BaTiO3 on the dielectric properties of the MWCNT/PVDF nanocomposites was attributed to deteriorated conductive network. (C) 2014 Society of Plastics Engineers