Improving the dielectric performance of poly(vinylidene fluoride)/polyaniline nanorod composites by stretch‐induced crystal transition

Abstract

The introduction of conductive polyaniline (PANI) can significantly improve the dielectric constant of polymer‐based materials. However, there is a drawback of high dielectric loss. Herein, a simple and efficient stretching process was applied to improve the dielectric performance of poly(vinylidene fluoride)/PANI (PVDF/PANI) nanorod films through the stretch‐induced crystal transition from non‐polar α‐crystal to polar β‐crystal in PVDF and the oriented distribution of PANI nanorods. XRD, DSC and Fourier transform IR analyses indicate that the stretched PVDF and stretched PVDF/PANI films possess a high content of β‐crystal at the stretching temperature of 135 °C under a stretching ratio of 200%–400%. Furthermore, the stretched PVDF/PANI film with 10 wt% PANI displays a high dielectric constant of 338 at 100 Hz, which is increased by 20% compared to non‐stretched PVDF/PANI film (281). More importantly, the corresponding dielectric loss is reduced from 0.31 for the non‐stretched film to 0.17 for the stretched film. © 2018 Society of Chemical Industry

Comparative Study of PVDF Sheets and Their Sensitivity to Mechanical Vibrations: The Role of Dimensions, Molecular Weight, Stretching and Poling

“…In addition, there are various processing techniques to transform the initial α-phase to its electro-active β-phase analogue, such as the addition of particles [ 19 , 20 ], electrospinning [ 21 , 22 ] or melt-electrowriting [ 23 ]. There were several studies performed, not specifically on the PVDF, but also on the composite systems which independently and in various conditions showed the piezoelectric activity of the films with various molecular weights: low [ 24 ], medium [ 25 , 26 ] and high [ 27 ]. How the molecular weight influenced the piezoelectric activity if various molecular weights were applied for the electrospun fiber mats was also recently presented [ 28 ].…”