Design and wearable sensing study of a temperature-sensitive anti-freezing biomass conductive gel based on IPANH@DES

Abstract

Conductive hydrogels derived from biopolymers are rapidly gaining prominence as a key research direction in the field of flexible wearable sensors. However, the limitations of poor mechanical properties and unstable electrical properties significantly hinder the application of conductive hydrogels in wearable sensors. In this study, we addressed these issues by introducing polymers as the first network and hydroxypropyl chitosan (HPCS) as the second network within metal salts and low eutectic solvent systems. This approach resulted in the development of biomass-based conductive gels, designated as IPANH@DES (low eutectic solvent based acrylate-co-N-isopropylacrylamide chitosan ionic conductive gel). Thanks to the abundance of associative hydrogen bonds within the conductive hydrogel network, the material demonstrates exceptional conductivity (0.08 S cm⁻¹) and frost resistance down to −47 °C. Wearable sensors fabricated with this hydrogel are capable of accurately capturing real-time motion signals across a range of environments. At 100% stretch, the GF is as high as 7.49. Consequently, the conductivity and antifreeze properties of the IPANH@DES based conductive hydrogel offer a novel approach. The development is anticipated to have promising application prospects in the field of flexible wearable sensors, particularly for human motion monitoring. It is expected to facilitate the applications in this domain.