Predictability of Dielectric Constant of Polyvinylidiene Fluoride- BaTiO3 (PVDF/BT) Composite based on Input Concentration of BaTiO3 and its Associated Electric field Frequency

Abstract

The dielectric constant of polyvinylidene fluoride-BaTiO₃ (PVDF/BT) composite was predicted based on the input concentration of BaTiO₃ (filler) ɤ and associated electric field frequency Ғ. This followed the development of a model equation relating the dielectric constant, BaTiO₃ input concentration, and electric field frequency. The PVDF/BT composite was produced using a step-by-step process, involving hot-pressing the input materials such that the ceramics component is wrapped by the polymer. The validity of the derived model expressed as; K=  ẞe^ɸɤ + ϦҒ^ɱ - N was rooted in the core expression K - ẞe^ɸɤ ≈  ϦҒ^ɱ - N, in that both sides of the expression are correspondingly near-equal, where ẞ, ɸ,  Ϧ, ɱ and N are the equalizing constants. According to the results of both experiments and model predictions, the dielectric constant increases with increasing filler loading and electric field frequency, as reported previously. The evaluated results demonstrated that the correlations between the dielectric constant, filler loading, and electric field frequency are 0.9982, 0.9955, and 0.9982, respectively, using model-predicted and experimental results, showing the responses of the composite`s dielectric constant to the highlighted influencing factors. The overall standard error incurred in predicting the dielectric constant of PVDF-BT composite is ˂ 0.18%, for every change in the electric field frequency & BaTiO₃ input concentration. The PVDF-BT composite dielectric constants per unit electric field frequency and BaTiO₃ input concentration are 7.77 x 10^-6, 7.58 x 10^-6& 6.84 x 10^-6 (Hz)^-1 and 1.84, 1.80 & 1.62 (wt%)^-1 as evaluated from experimental, derived model and regression model-predicted results. The highest deviation of the model-predicted dielectric constant (from experimental or real measurements) was less than 1.9%. This resulted in over 98% operational confidence in the resulting model and over 0.98 response coefficients for the dielectric constant's dependence on electric field frequency and BaTiO₃ input concentration.