Highly Stretchable, Ultra-Sensitive, and Self-Healable Multifunctional Flexible Conductive Hydrogel Sensor for Motion Detection and Information Transmission

Abstract

Self-healable flexible sensing materials are extensively investigated for their potential use in human motion detection, healthcare monitoring, and other fields. However, the existing self-healable flexible sensing materials have limited their application in real life due to the weak stability of the conductive network and the difficulty in balancing stretchability and self-healing performances. In this paper, a flexible sensor with skin-like properties was prepared by composing a polymer composite hydrogel with a multiple network structure consisting of polyaniline, polyvinyl alcohol, chitosan, and phytic acid. The composite hydrogel was tested and proved to own high mechanical properties (stretchability ≈ 565%, strength ≈ 1.4 MPa), good electrical conductivity (0.214 S cm–1), excellent self-healing properties (>99% healing efficiency in a 4 h healing period), and antibacterial properties. It had high sensitivity and a wide sensing range for strain and pressure, making it possible to manufacture multifunctional flexible sensors with comprehensive performance exceeding that of most flexible sensing materials. Notably, this polymer composite hydrogel can be manufactured in a large area and at a low cost, which is beneficial for its further application in many fields.

Sandwich-Type Self-Healing Sensor with Multilevel for Motion Detection

“…The short response time allows the sensor to respond to behavior in a timely manner with low latency. Self-repairability in turn allows the sensor to not only extend its lifetime but also to ensure signal security. , …”

“…Self-repairability in turn allows the sensor to not only extend its lifetime but also to ensure signal security. 39,40 To test the sensing materials prepared from sandwich-type composites for motion detection applications and to further compare the performance effects of the presence or absence of THF in conductive fillers in the field of motion detection, we conducted a series of motion tests on PIH-Zn 10 -G 0.5 /CNT-KH560, PIH-Zn 10 -G 0.5 /CNT-KH560(−THF). The PIH-Zn 10 -G 0.5 /CNT-KH560 sandwich-type composite exhibited excellent stability and repeatability in terms of resistance change generated by transient movements such as finger bending and pressing the keyboard.…”

Recent progress in the development of conductive hydrogels and the application in 3D printed wearable sensors

“…High stretchability enables comfortable and unrestricted wear, ensuring reliable data collection from the sensors. 82,83 To enhance the mechanical properties of conductive hydrogels, one commonly employed approach is to incorporate additional constituents into the hydrogel matrix. This strategy enables the formation of diverse reversible dynamic bonds with the hydrogel matrix, thereby enhancing its stretchability and toughness.…”

“…High stretchability enables comfortable and unrestricted wear, ensuring reliable data collection from the sensors. 82,83…”

Fabrication of anti-freezing and self-healing nanocomposite hydrogels based on phytic acid and cellulose nanocrystals for high strain sensing applications

“…As another emerging biomass-derived material, phytic acid (PA) is a non-toxic biomacromolecular material extracted from plant seeds with good biocompatibility and effortless raw material supply. 22–24 As a non-toxic bioorganic acid, naturally extracted PA is an environmentally friendly material and has been widely used as a crosslinking agent, gel and food preservative. 25 Moreover, PA containing six phosphate groups provides abundant donor and acceptor positions of hydrogen bonds, which can combine with H 2 O molecules through hydrogen bond interactions, effectively preventing crystallization and enhancing the anti-freezing properties of hydrogels.…”