Enhancing Thermal and Insulation Properties of Materials via Plasma-Treated Silica Micropowder Fillers

Epoxy resin is widely used in electronic packaging materials due to its excellent mechanical strength and electrical properties; however, its poor thermal conductivity limits its application in high power density aerospace measurement and control equipment. To enhance its overall performance, this study introduces silica micropowder fillers modified by atmospheric pressure low-temperature plasma. A rotary dielectric barrier discharge reactor was employed to functionalize the filler surface, significantly improving the interfacial adhesion between the fillers and the epoxy resin matrix. Experimental results show that the thermal conductivity of the modified composite material reached up to 0.647 W/m·K, representing an 80.73% increase compared to pure epoxy resin. The dielectric breakdown strength was improved to 80.62 kV/mm, a 39.19% increase compared to the unmodified filler system. The incorporation of modified silica micropowder demonstrated significant advantages in enhancing thermal conductivity, insulation performance, and interfacial stability, offering an effective approach and technical support for the development of high-reliability electronic packaging materials.