Stretchable, conductive poly(acrylamide-co-maleic acid)/triethylene glycol/NaCl double-crosslinked organohydrogel with excellent antifreezing and sensing properties

Recently, the wearable electronic devices have attracted extensive attention while the low stretchability and freezing-induced performance deterioration largely limit the applications in many fields. In this work, the poly(acrylamide-co-maleic acid) hydrogels are immersed in the triethylene glycol/sodium chloride/water solution to establish the dual-crosslinked organohydrogels, which present the extraordinary stretchability (1322 +/- 75%) ascribed to the energy dissipation of physical interactions and stability of chemical crosslinked networks. Triethylene glycol forms strong hydrogen bonds with water, which interfere with the formation of intermolecular hydrogen bonds among water molecules at low temperatures and inhibit the formation of ice crystals in the organohydrogel networks. Sodium chloride imparts excellent electrical conductivity to the organohydrogel. As a result, a stretchable electronic sensor based on the organohydrogel is fabricated, which is strain-sensitive with a wide strain sensing window (0%-440%) and excellent stability. More importantly, the sensor based on the as-prepared organohydrogel could precisely detect various activities of the human model at -30 degrees C leading to the widely application prospects.

Automated summary

In this study, the researchers developed a dual-crosslinked organohydrogel by immersing poly(acrylamide-co-maleic acid) hydrogels in a solution of triethylene glycol, sodium chloride, and water. The organohydrogel showed extraordinary stretchability and excellent electrical conductivity due to physical interactions and chemical crosslinked networks. A stretchable electronic sensor based on this organohydrogel was fabricated and demonstrated a wide strain sensing window and excellent stability. Importantly, the sensor could accurately detect various activities at low temperatures, showing promising prospects for applications.