Intrinsically Conductive, Highly Compressible, Porous Hydrogel with Exceptional Sensitivity at Low Pressure.

Abstract

Conductive hydrogels have emerged as a promising material in the field of flexible sensing, holding great potential for advanced wearable devices and medical diagnostics, because of their unique conductivity, mechanical deformability, and tissue-like softness. However simultaneously achieving intrinsic conductivity, excellent compressibility and resilience remains a significant challenge. Herein, a novel macroporous, highly compressive, resilient, and intrinsically conductive hydrogel (MPGEL) based on a newly developed easy, eco-friendly, and zero-waste strategy is reported. The MPGEL is prepared using nitrogen as the inert gas and foaming agent, polymerizable Pluronic F127 as a surfactant and crosslinker, and ionic conductive lithium acrylate (LiAA) as the monomer. The resulting MPGEL exhibits highly compressibility and resilience with a low compressive modulus (3.75 kPa), yielding an exceptional compressive sensitivity of 31.67 kPa^-1 at low pressure. Therefore, the MPGEL not only can monitor various human movements, but also can effectively detect human cardiac motion, and even precisely distinguish between central and peripheral arterial blood pressure waveforms. This highlights the immense potential of MPGEL for future medical diagnostic technologies and advanced wearable health-monitoring devices.