PDMS/SiC functionally gradient substrate fabricated by 3D printing and its performances

Abstract

<p indent="0mm">Substrates used in flexible electronics, electronic clothing, wearable devices, soft robotics, etc., need to have the properties that include functionally gradient variable rigidity, excellent heat dissipation, and biocompatibility. Nevertheless, these criteria cannot be met well by the current substrates. A functionally gradient substrate PDMS/SiC is proposed using the PDMS as a matrix material and the SiC as a reinforcing step (filler) and the SiC content gradient distribution. To address the challenging issue of manufacturing PDMS/SiC functionally gradient substrate, a novel method of manufacturing using a multi-material 3D printing process with active mixing nozzle is proposed to create the functionally gradient substrate at low cost and high throughput. The PDMS/SiC functionally gradient substrate is obtained by combining the proposed approach with optimized parameters. Compared to traditional PDMS substrates, the latest substrate’s thermal conductivity is increased by 2.5 times, and 50% side Young’s module of SiC material is increased by 2.9 times. Besides, the substrate’s rigidity varies gradually. The experimental findings show that the functionally gradient substrate PDMS/SiC provides a new high-performance substratum for flexible electronics, electronic skin, wearable electronics, soft robot, etc.