Plant-Derived Hydrogels\nwith High Stretchability and\nAdhesion for Multifunctional Sensors

Hydrogels have broad application prospects in biomedicine,\nenergy,\nand tissue engineering due to their high water content, adjustable\nphysicochemical properties, and flexibility. In general, the poor\nstretchability and adhesion of hydrogels limit their application in\nflexible wearable electronics. In this work, a composite hydrogel\n(GM hydrogel) with excellent adhesion, stretchability, and conductivity\nwas prepared by a one-pot synthesis process through the hydrogen-bonding\ninteraction between P(AM-<i>co</i>-AA)) and gallic acid\n(GA). Natural plant polyphenol GA not only enhances the mechanical\nproperties of the hydrogel (maximum tensile strain of 890% and maximum\ntensile stress of 238 kPa) but also gives the hydrogel adhesion (9\nkPa). GM hydrogel can be further used to construct strain sensors\nand self-powered sensors. GM hydrogel strain sensors can be attached\nto finger joints to monitor and distinguish the angles of finger joint\nbending. Self-powered sensors based on GM hydrogels can stably transmit\nencrypted signals. Therefore, multifunctional GM hydrogels can be\nused for electronic skin, human motion monitoring, and wearable biosensors.