Electrical transport in 0-3 epoxy resin-barium titanate-carbon black polymer composites

Abstract

Conductivity and dielectric constant of a three-component 0-3 composite of epoxy resin–barium titanate–carbon black (0-3 composites are systems in which the filler is in the form of 0-dimensional (point-like, disperse) particles in a three-dimensional polymeric matrix1) have been investigated both at DC and the frequency range of 20–106 c/s. The effect of barium titanate concentration on percolation threshold, critical indices and the mechanism of conduction has been examined. An attempt was made to describe the electrical properties of composites with models originally developed for two-component systems' dielectric-conductor. With increasing barium titanate concentration the agreement of experimentally found frequency dependencies of conductivity and dielectric constant with models based on Debye's equation was found to degrade. An adequate description of electrical properties of composites' dielectric–ferroelectric-conductor should be based on the Havriliak–Negami equation. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 1847–1856, 1998