Self-healing and freezing-tolerant strain sensor based on a multipurpose organohydrogel with information recording and erasing function

Abstract

Smart hydrogels with various stimuli-responsiveness have shown tremendous prospects in the areas of electronic skins, artificial medical organization and soft robotics. Herein, a multifunctional organohydrgel is prepared by introducing polyvinylpyrrolidone (PVP), acrylic acid (AA) and acrylamide (AAm) into water/dimethyl sulfoxide (H2O/DMSO) binary solvent system. The introduced PVP and chemical cross-linked P(AA-co-AAm) chains based double network structures and the amount of reversible hydrogen bonds between polymer chains endow the as-prepared organohydrogel with excellent mechanical property (1554 % strain) and self-healing capability. Meanwhile, the organohydrogel exhibits extraordinary low-temperature tolerance (−40 ℃) and long-term anti-drying property (83 % moisture retention after 7 days) due to the strong interactions between water and DMSO. Furthermore, the flexible strain sensor based on the organohydrogel displays a wide strain sensing range (0–500 %) and repeatable response capability, which can precisely monitor varying degrees of stretching deformations and a series of intricate human movements. Owing to the remarkable freezing resistance and self-healing property, the original and healed organohydrogel sensors still exhibit stable sensing behaviors in freezing environment of −40 ℃. Noticeably, the obtained organohydrogel can also be served as a special paper to realize the information recording and erasing function at subzero temperatures. These outstanding performances indicate the organohydrogels may be employed as durable and freezing-tolerant smart materials applied in future flexible electronics, soft robots and information platform.