Significant enhancement of thermal conductivity and EMI shielding performance in PEI composites via constructing 3D microscopic continuous filler network

Polymer-based composites with effective heat dissipation and ideal electromagnetic interference shielding performance have gradually become an essential research focus in modern electronic industry. Herein, a method is reported by constructing 3D microscope continuous filler network into polyetherimide (PEI) matrix via incorporating function graphite nanoplatelets (GNP) with PEI microspheres, and then fillers are distributed beyond the domain area of polymer and leaded to continuous filler framework. The fabricated composites exhibit effective thermal conductivity (4.77 W m � 1K-1), great EMI effectiveness (42.7 dB), ideal electrical conductivity and profound thermal property. Different scale of polymer microspheres will also change the micro-architecture from "filler-wrapped polymer" structure to "polymer-wrapped filler" structure, resulting in various thermal performance and electrical property. Finite element simulation is further employed to explore the relationship between microsphere scale and heat transfer behavior. In a word, great comprehensive performance endows PEI composites broaden prospect on the potential applications in the fields of electronic equipment.