Molecularly Ordered Epoxy/Organic Acceptor Composites for Superior Thermal Transport and Electrical Insulation Performance

Abstract With the growing demand for high‐performance electrical equipment, especially for power semiconductors, it is critical to develop advanced packaging materials with excellent electrical insulation, thermal conductivity, and high temperature stability. However, the simultaneous enhancement of thermal conductivity and dielectric breakdown strength is still a great challenge. Herein, a series of molecularly ordered epoxy/organic molecular acceptor composites is prepared by constructing a naphthoic anhydride‐biphenyl complex to induce well‐organized electrophilic epoxy resin, thus achieving a significant improvement in dielectric breakdown strength and thermal conductivity. For instance, the introduction of only 0.4 wt.% naphthoic anhydride into the biphenyl epoxy monomer increases the dielectric breakdown strength at room temperature by 11.3%. More importantly, its high‐temperature dielectric breakdown strength at 200 °C only decreased by 13.6% compared to that at room temperature. In addition, the thermal conductivity of this epoxy film increased to 0.544 W m·K ⁻¹ , ≈2 times higher than that of the original sample. This work elucidates a novel and scalable methodology for the design of polymer‐based packaging materials with exceptional electrical and thermal properties, and it is promising to address the critical demands of electrical equipment in extreme working environments.