Three-Dimensional Printing to Fabricate Graphene-Modified Polyolefin Elastomer Flexible Composites with Tailorable Porous Structures for Electromagnetic Interference Shielding and Thermal Management Application

Revolutionary communication technologies including 5G and their correlated microelectronic equipment have generated the new generation of electronic components with a higher power density, which not only would bring electromagnetic waves (EMWs) radiation pollution but also would produce a lot of waste heat problems. In order to satisfy the requirements of advanced electronic components for the multifunctionality, light weight, flexibility, and complex structure, in this work, the polyolefin elastomer (POE)/graphene nanoplatelets (GNPs) nanocomposites with tailorable porous structures were successfully prepared through effectively combining the ultrasonic dispersion strategy with the fused deposition modeling (FDM) 3D printing technology. The results show that the synergistic effect of the constructed GNP network structure and the FDM printed porous structure could effectively enhance the electromagnetic shielding (EMI SE) performance of the 3D printed parts and meet their increasing demands for thermal management. When the content of the incorporated GNPs is 10.93 vol %, the EMI shielding efficiency (SE) value of the printed part could be up to 35 dB, and the value of the thickness-normalized specific SE (SSE/t) under the best printing conditions (50% infill density) could reach up to 244.9 dB·cm2/g. In addition, the achieved maximum thermal conductivity is 4.3 W/(m·K), which is 1600% higher than that of the pure POE matrix. The excellent flexibility of the printed pad also ensures its good contact with the electronic device during operation. Finally, the COMSOL simulation results verify the application feasibility of the FDM printed part. This work provides a novel strategy for preparation of customizable and multifunctional porous flexible parts, which is expected to be applied in the field of microelectronics such as communication intelligent devices.