The Micro‐Nano Hybrid Filler Al ₂ O ₃ @ CuNPs Is Used to Improve the Thermal Conductivity of Epoxy Resin Composites

In this study, a micro/nano hybrid filler comprised of Al 2 O 3 @CuNPs is synthesized through a chemical reduction method. The incorporation of Cu nanoparticles serves as a bridge, addressing the contact issues within the filler and substantially enhancing its ability to establish a thermal conductivity network. The filler loading was kept at a constant level up to 70 wt%; however, the copper amount was varied between 0 and 10 wt%. The resulting thermal conductivity of the Al 2 O 3 @CuNPs/EP composite exhibits a gradual increase with the filler content, reaching 1.06 W/mK at a total filler content of 70 wt%. This represents a remarkable growth rate of 457.9% compared to pure EP. This material holds promising potential for applications in thermal conductivity materials.