(580c) Liquid Metal Crosslinked Poly(3,4-ethylenedioxythiophene) Polystyrene Sulfonate (PEDOT: PSS) Conductive Hydrogel

Conductive hydrogels play a significant role in bio-interfaces, bioelectronics, and medical purposes because of its excellent properties like high water content and excellent flexibility. However, the approaches to fabricate conductive hydrogel always cause low conductivity and poor biocompatibility, which limit the application in bio-interfaces and bioelectronics. In recent years, a conductive polymer complex, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS) has emerged as a potential material to fabricate conductive hydrogel. At same time, gallium-based liquid metal exhibits good performance in soft bioelectronics. Therefore, our recent work has developed a new method to synthesize PEDOT: PSS hydrogel based on the liquid metal eutectic gallium-indium (EGaIn). We use sonication to break EGaIn into homogeneous nanoparticles, which can crosslink PEDOT: PSS polymer into conductive hydrogel very quickly. To gain insight into the crosslinking process, we have put forward two different mechanisms, which are expected to be identified. According to rheological characterization, we found that the strength of the hydrogel increases over time until it reaches a plateau after two weeks, which can be related to the release of gallium ions. We also preliminarily measured the conductivity of the hydrogel and gained a deeper understanding of PEDOT: PSS hydrogel. We expect to improve its performance to meet the relative application.