Space charge behavior on epoxy based composite materials with high nanoparticle content

The main objective of this paper is to give an electrical characterization of epoxy based nanocomposite materials. These innovative materials are composed of an cycloaliphatic epoxy with a flexibiliser mixed with 0, 1, and 20%wt Nanopox®. These materials are aimed to be used for electrical engineering applications and they should have a significant increase in electrical performances compared to the reference material (neat epoxy). Many studies have been carried out on epoxy based nanocomposite samples with a weak content of nanofiller. In this work, we aim to evaluate the influence of a high concentration of nanofiller, up to 20 %wt, on the electrical properties of the samples. The stability of the sample´s dielectric response has been evaluated and a post heat treatment has been performed. The loss factor has been measured for different nanofiller concentrations at 60°C. Then, space charge measurements have been performed for different poling conditions (“low” and “high” applied electric field). Glass transition temperatures “Tg” have been measured on the different materials and the poling temperature (60°C) has been fixed below the lowest Tg. With the nanofiller content, the effect of the applied electric field on space charge accumulation is shown.