Facile preparation and characterization of tough poly(vinyl alcohol) organohydrogels with low friction and self-cleaning properties

Although many hydrogels have been applied to wearable sensors, it is still challenging to simultaneously realize hydrogels with optical transparency, superior mechanical properties, excellent sensing performance, and anti-freezing by using inexpensive raw materials and an easy preparation process. Herein, using ethylene glycol/H 2 O (EG/ H 2 O) as a solvent, poly(vinyl alcohol)/EG organohydrogel (PVA/EG OHG) was prepared by a simple heating and frozen-thawing method. Owing to the multifunctionality of EG (i.e., physical cross-linker, anti-freezer and co-solvent), PVA/EG OHG demonstrated excellent integrated properties, including high strength, high toughness, and anti-freezing performances. Besides, PVA/EG OHG also showed low friction, self-cleaning, and frost resistance properties. After the introduction of LiCl, ionically conductive PVA/EG @LiCl organohydrogel was served as a self-cleaning strain sensor, which could be long-term stable to detect the motions of human under room and low temperatures. The study provides to further understanding of the organohydrogel, which will help us design next-generation high-performance organohydrogels.