Poly-etherimide epoxy diamine blends: Conductivity and breakdown voltage measurements at room temperature.

Abstract This paper presents an investigation on the current and breakdown voltage measurements in thermoset-thermoplastic blends based on an epoxy-amine/poly-etherimide phase separated material. Thermoset-thermoplastic separated blends could be a novel material for insulation applications and can be compared to epoxy/inorganic composites systems. Pure epoxy network as well as the blends with 10 wt% of PEI were studied in terms of conduction and transient currents. An ohmic behavior below the threshold field (E th) and space-charge-limited conduction (SCLC) above E th are pointed out. Contact emission phenomenon was investigated by means of Schottky model and seems to be valid for both materials. The addition of 5 and 10 wt% of PEI into the epoxy system showed an increase in the values of breakdown voltage with the increase of the PEI amount. Highlights • Electrical characterization of an epoxy/thermoplastic blend is examined • Current is controlled by volume phenomena through SCLC approach • Epoxy and blends showed contact emission at the electrode/sample interface • Breakdown voltage increased with the increase of the percentage of thermoplastic [ABSTRACT FROM AUTHOR]