A new strategy for the preparation of silver/epoxy/poly(vinylidene fluoride) dielectric composites with a multi-interface structure for suppressed dielectric loss

Dielectric materials with low dielectric loss are highly desirable for future energy storage and management. Relatively high dielectric loss and complex fabrication process with high cost are current major factors limiting percolative dielectric composites for applications. In this study, low dielectric loss has been obtained using multi-interface silver/epoxy/poly(vinylidene fluoride) (Ag/epoxy/PVDF) percolative composites by simple thermal curing and mechanical crushing, coupled with melt mixing and hot pressing. Isolated Ag/epoxy islands were formed in the PVDF matrix. The dielectric permittivity of the composite near the percolation threshold reached 132 whereas the loss tangent was around 0.1 at 100 Hz. This multi-interface structure played an important role in suppressing the dielectric loss and achieving the relatively high dielectric permittivity in these composites. Our results suggest that the simple and low-cost fabrication of the Ag/epoxy/PVDF is a promising approach for the development of low-loss percolative dielectric composites. POLYM. COMPOS., 39:E2606–E2610, 2018. © 2018 Society of Plastics Engineers