Ultrastretchable, Adhesive, Anti-freezing, Conductive, and Self-Healing Hydrogel for Wearable Devices

Abstract

Ultrastretchable, conductive, and autonomous adhesive hydrogels have attracted serious concern due to their wide and promising application in soft electronics, wearable strain sensors, and personal health monitoring. However, traditional hydrogels would lose their properties at subzero temperature, which greatly restricts their applications in a variety of fields. Herein, we fabricated an ionic conductive cellulose hydrogel with ultrastretchable, adhesive, anti-freezing, and self-healing properties. The obtained hydrogel displays ultrastretchability (3280% of tensile strain), anti-freezing property (−32 °C), high conductivity (2.0 S/m at 20 °C, 1.4 S/m at −20 °C), and good self-healing ability. The hydrogel also showed excellent adhesion performance under a broad range of temperatures (9.6 kPa at 20 °C, 5.5 kPa at −20 °C). In addition, the hydrogel-based sensor demonstrated high strain sensitivity and quick responsivity to various human movements. Thus, this work provided a simple pathway to prepare an adhesive, anti-freezing, conductive, and self-healing hydrogel as human motion detection devices.