From filler to structure: Designing 3D-printable silicone elastomers with broadband electromagnetic interference shielding

Abstract

Material extrusion has revolutionized the fabrication of silicone elastomers with intricate and customized structures. However, the trade-off between the ink printability and functional filler compounding impedes the advancement of 3D-printed silicone elastomers for applications such as electromagnetic interference (EMI) shielding and thermal management. In this study, we present a novel approach to fabricating functional silicone elastomers, focusing on the design of fillers, inks and structures. Ink printability was achieved by modified nanosheets, which conferred the thixotropy and self-support capacity to inks by constructing dynamic interfacial interactions within the silicone matrix. Additionally, modified nanosheets exhibited a “lubricating” effect under high shear rates owing to their layered structure, thereby facilitating a smooth extrusion process. Utilizing EMI shielding simulations of periodic porous structures as a guide, we successfully printed broadband EMI shielding silicone elastomers. Furthermore, the versatility of our approach was demonstrated through the creation of customized 3D-printed shielding boxes and wearable thermal management films, showcasing the diverse potential applications of the 3D-printed silicone elastomers. We anticipate that our innovative design approach will bridge the gap between functional elastomers and 3D printing technology, opening up new avenues for their applications in various fields.