The Dielectric Properties Of Polyvinylidene Fluoride-based Composites Under The Influence Of External Field

The development of high mechanical properties and high energy storage ability in dielectric materials is adopted to meet the requirement of miniaturization and integration of the electronic device, which is the key issue of the development of current electronic technology. Although some research made a breakthrough in design and preparation of the polymer-based composites, the enhancement of dielectric properties was still unsatisfied. On the other hand, external field modification is the effective method to improve the dielectric properties of polymer-based composites. In this article, the stress field and magnetic field were used to enhance the dielectric properties of PVDF/Ni Composites, while keeping the excellent mechanical properties of the polymer matrix either.In our present work, our research is focused on the modification of dielectric properties of PVDF/Ni composites. It was found that the composites exhibit a relatively high permittivity (nearly ten orders of magnitude increment) due to the insulator-conductor transition caused by the influence of the external press field. Similarly, there is a percolation when the PVDF/Ni composites film under high tensile strain, the nickel particles array in parallel as rod-like clusters along with the stretching direction, resulting in high permittivity (230). Furthermore, a percolation effect could be induced by an external magnetic field in low filler PVDF/Ni composites. Different from the traditional percolation effect, the fields induced percolation is anisotropic, exhibiting abrupt increase of the permittivity along with the direction of external fields.