Preparation and properties of polyvinylidene fluoride/tetra‐needle like‐zinc oxide whisker composites

With the rapid development of the electronics industry, dielectric materials with a high‐dielectric constant are playing an increasingly important role in the performance of electronic devices. In this study, a composite that employed polyvinylidene fluoride (PVDF) as a matrix and four‐needle zinc oxide whisker (T‐ZnOw) for reinforcement was prepared by casting method. The microstructure and crystallization behavior of the PVDF/T‐ZnOw were analyzed by SEM, FT‐IR and XRD. Thermal stability and electrical properties of the composites, included the dielectric constant, dielectric loss and electrical breakdown strength, were tested. Analysis on microstructures indicated that the T‐ZnOw in composites were uniformly dispersed and some of the whisker's tips had penetrated through the surface of the composites because of the special four‐needle structure. Experimental results showed that the addition of T‐ZnOw significantly improved the thermal stability of the composites. Broadband dielectric spectroscopy test results showed that the dielectric properties and conductivity of the composites significantly improved with the increase in T‐ZnOw contents. The dielectric constant of the composites was 113 at 100 Hz when the T‐ZnOw content was 20% at weight content.