Highly Retained Electric and Mechanical Traits in Micron-Sized Glass Fibers Filled Epoxy Composite Based on Heat-Oxygen Ageing

Abstract

The epoxy based composite materials with a high ageing resistance property have attracted a wide attention in the field of high-electric-insulation electronic packaging. However, both of the highly retained electrical and mechanical performances are difficult to simultaneously achieve in composite materials once a longer heat-oxygen ageing at a high temperature is applied onto the materials. In order to realize the ageing-resistant high mechanical, electric breakdown and dielectric properties simultaneously in composite, in this work, an epoxy based composite filled with the high-insulation micron-sized glass fiber filler has been prepared, and its shock resistance strength, electric breakdown strength, dielectric constant, dielectric loss and conductivity after a severe heat-oxygen ageing have been investigated in detail, compared with that before the ageing. Although the ageing was operated at 150 °C for 25 days, the electric and mechanical properties of the composite were still finely retained, including 60% retention for shock resistance strength, 70% for breakdown strength, 80% for dielectric constant, dielectric loss below 0.1 and conductivity below 2 × 10⁻⁹ S cm⁻¹. The epoxy matrix and glass fiber filler were responsible for the small decline and high retention for the properties in composite, respectively. This work might open the way for the large-scale preparation of the promising epoxy based composites with the highly retained ageing-resistant electric and mechanical properties based on incorporating the high-insulation fiber fillers.