Synthesis and evaluation of PVDF-MgTiO3 polymer-ceramic composites for low-k dielectric applications

摘要

PVDF exhibits ferroelectric, pyroelectric, and dielectric properties as a function of its unique crystalline phases, namely , , , , and epsilon. Of these, the crystalline phase shows unique electrical and mechanical properties due to its highly ordered crystalline lamellae and is of industrial interest. Electrospinning is a unique technique to produce long flawless fibers for various applications. In this study, several MgTiO3-PVDF composites were prepared by the electrospinning and solution-casting methods. The objective of this was to examine the combined effect of a popular, low-loss ceramic dielectric like MgTiO3 and a high-dielectric polymer like PVDF in a new architecture. The effect of the filler dispersion on the microstructure, phase transition, and mechanical and electrical properties of the MgTiO3/PVDF composites was investigated in the frequency range of 100 Hz-100 MHz and at 10 GHz. The dynamic mechanical properties of the composites (1-100 Hz) have also been examined. These polymer composites composed of highly crystalline PVDF nanofibers and MgTiO3 appear to have promising dielectric properties distinctly different from their constituent components.