Highly stretchable anti-freeze hydrogel based on aloe polysaccharides with high ionic conductivity for multifunctional wearable sensors

作者：Xiao, Suijun; Lao, Yufei; Liu, Hongbo; Li, Dacheng; Wei, Qiaoyan; Li, Ziwei; Lu, Shaorong^*

来源：International Journal of Biological Macromolecules, 2024, 254: 127931.

DOI：10.1016/j.ijbiomac.2023.127931

• Aloe vera polysaccharide
• Wearable sensor
• Anti-freezing

Conductive hydrogels have limitations such as non-degradability, loss of electrical conductivity at sub-zero temperatures, and single functionality, which limit their applicability as materials for wearable sensors. To overcome these limitations, this study proposes a bio-based hydrogel using aloe polysaccharides as the matrix and degradable polyvinyl alcohol as a reinforcing material. The hydrogel was crosslinked with borax in a glycerol-water binary solvent system, producing good toughness and compressive strength. Furthermore, the hydrogel was developed as a sensor that could detect both small and large deformations with a low detection limit of 1 % and high stretchability of up to 300 %. Moreover, the sensor exhibited excellent frost resistance at temperatures above-50 degrees C, and the gauge factor of the hydrogel was 2.86 at 20 degrees C and 2.12 at-20 degrees C. The Aloe polysaccharide-based conductive hydrogels also functioned effectively as a wearable sensor; it detected a wide range of humidities (0-98 % relative humidity) and exhibited fast response and recovery times (1.1 and 0.9 s) while detecting normal human breathing. The polysaccharide hydrogel was also temperature sensitive (1.737 % degrees C- 1) and allowed for information sensing during handwriting.

• 单位
  桂林理工大学