Self-assembly polysaccharide network regulated hydrogel sensors with toughness, anti-freezing, conductivity and wide working conditions

Abstract

Ionic conducting hydrogel acted as a promising candidate in flexible electronic device, however, the intrinsic properties of weak mechanical strength, conductivity and environmental instability still are the challenging task. Herein, an assembled polysaccharide network (acetylated distarch phosphate) regulated polyvinyl alcohol (PVA/ADSP) hydrogel is fabricated via one-step freeze–thaw method, the stress, elongation at break, elastic modulus, and toughness could reach 2.26 MPa, 818.60 %, 0.95 MPa, and 12.23 kJ/m3, respectively. At the same time, the binary solution interlocked structure and salt are introduced into the PVA/ADSP hydrogel realizing the great environmental stability (water-retention and anti-freezing) and conductivity (3.59 S/m). PVA/ADSP hydrogel act as strain sensor presenting the great responsibility (128 ms), strain sensitivity (GF=1.82 at 350–500 % of strain) and durability. On account of the excellent sensing characteristics, the PVA/ADSP hydrogel could reliably, accurately and consistently detect most of human exercises and subtle physiological activities (electrocardiography) in real-time. Moreover, PVA/ADSP hydrogel is also utilized to control robotic hand realizing the human–machine interaction. This work provides a novelty regulated approach for conducting hydrogel via self-assembled polysaccharide network, which contributes to the innovative advancement of flexible wearable electronics.