Improving the thermal conductivity of epoxy resins with mesogenic units for electronic packaging

Abstract

The heat dissipation is very important for electronic packaging. We have improved the thermal conductivity of electronic packaging materials by modifying epoxy resin with tetraester diepoxide monomers (TEDE). TEDE was synthesized with p-hydroxybenzoic acid, allyl bromide and glycols, and characterized by 1H-NMR. TEDE modified epoxy resin (TMEP) was cured by 4, 4'-diaminodiphenyl-methane (DDM). Thermogravimetric (TG) analysis show that the decomposition temperature of TEDE is above 280 °C, and the decomposition temperature of TMEP is above 300 °C in nitrogen atmosphere. Differential scanning calorimetry (DSC) and polarized optical microscope (POM) were employed to illustrate that TEDE is liquid crystalline polymer form room temperature to 220 °C. Dynamic mechanical analysis (DMA) illustrate that the glass transition temperature (Tg) of TMEP materials decrease with the content of TEDE increase. The thermal conductivity was measured by laser thermal conductivity testing equipment. The results show that the glass transition temperature (Tg) of 30%TEDE modified epoxy resin is above 130°C, and the thermal conductivity is 0.64w/(m»K).