Electromagnetic interference shielding epoxy composites with satisfactory thermal conductivity and electrical insulation performance enabled by low-melting-point alloy layered structure

Nowadays, electronic packaging materials requires electrical insulation, heat conduction and electromagnetic interference (EMI) shielding performance. With the inspiration raised by Janus materials, introducing low-melting-point alloy (LMPA) layered structure in epoxy resin is potential method to acquiring satisfying properties. The layered structure is originated from LMPA particles self-sedimentation and closely stacking. Meanwhile, LMPA particles are coated by epoxy resin that could remain the overall electrical insulation. When loading of 20 vol% LMPA, composite obtained thermal conductivity 1.23 W/mK (the LMPA side), total EMI shielding value of 35.56 dB at 30 GHz, and electrical conductivity of 5.00 × 10−8 S/cm. Further, the introduction of boron nitride nanosheet (BNNS) into the composites could promote isotropic heat conduction and improve the electrical insulation. This paper has provided novel LMPA layered structure, showing great promise for applications of electronic packaging materials with heat conduction, electrical insulation and EMI shielding properties.