Polysaccharide-based ionic hydrogels: Comprehensive evaluation of conductivity, mechanical properties, and anti-freezing and anti-drying properties

The use of conductive hydrogels in flexible electronics has gained significant attention in recent years. However, the performance of traditional hydrogels is often hindered by dehydration at elevated temperatures and structural rigidity when frozen at low temperatures. In this study, we developed a double-network hydrogel consisting of ionically crosslinked pectin and covalently crosslinked polyacrylamide (PAAm) networks. Scanning Electron Microscopy (SEM) analysis revealed a highly interconnected and porous microstructure, which contributes to the enhanced mechanical strength and flexibility of the hydrogel. Through a solvent exchange process, the PAAm-pectin hydrogel was transformed into an organo-gel by immersing it in a binary solvent system of ethylene glycol and water. The incorporation of ethylene glycol significantly improved the hydrogel’s temperature tolerance, imparting superior anti-freezing and anti-drying properties. The resulting organogel exhibited remarkable transparency, excellent flexibility, and sustained ionic conductivity even at temperatures as low as −40°C. These attributes highlight the PAAm-pectin organogel as a promising candidate for next-generation flexible electronic devices, where performance stability under extreme conditions is essential.