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

Abstract

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/H2O (EG/ H2O) 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.