Impact of BaTiO₃ as insulative ferroelectric barrier on the broadband dielectric properties of MWCNT/PVDF nanocomposites

Abstract

This study was devoted to investigating the effects of BaTiO 3 incorporation on the broadband dielectric properties of melt-mixed multi-walled carbon nanotube/poly(vinylidene fluoride) (MWCNT/PVDF) nanocomposites. BaTiO 3 , 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 BaTiO 3 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% BaTiO 3 , respectively. It was also observed that incorporating BaTiO 3 muted the descending trends of dielectric permittivity and dielectric loss with frequency, confirming the role of BaTiO 3 as insulative barrier. The positive impact of BaTiO 3 on the dielectric properties of the MWCNT/PVDF nanocomposites was attributed to deteriorated conductive network. POLYM. COMPOS.,

Employing Nitrogen Doping as Innovative Technique to Improve Broadband Dielectric Properties of Carbon Nanotube/Polymer Nanocomposites

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