Interfacial metallization in segregated structured PEEK composite for enhanced thermal conductivity and electromagnetic interference shielding

The increasing integration of electronic devices has created an urgent demand for multi-functional composites with efficient thermal management and electromagnetic interference (EMI) shielding. In this study, a threedimensional (3D) continuous metal-carbon hybrid thermally/electrically conductive network structure is fabricated by in-situ nickel plating of core-shell structured polyetheretherketone (PEEK) hybrid particles. The hybrid particles realize phonon and electron dual heat-transfer pathways and reduce the interfacial thermal resistance by using metallic Ni nanoparticles to bridge the gap. Furthermore, the interfacial metallization and segregated structure significantly enrich the multiple electromagnetic wave reflection and attenuation mechanisms. The PEEK composites with metallized-segregated structure and filler content of 28.26 vol% exhibit an excellent through-plane thermal conductivity of 6.52 W m- 1 & sdot;K- 1 and an efficient EMI shielding of 91 dB, thus demonstrating their significant potential as multi-functional thermal management materials. The heat-transfer and EMI shielding process of the composites can be visualised using the finite element model, which further proves the effectiveness of the segregated structure and metallization. This simple and efficient strategy is expected to facilitate the manufacture of multi-functional thermal management composites with high thermal conductivity and excellent EMI shielding.