Highly Stretchable, Strain-Sensitive, and Ionic-Conductive Cellulose-Based Hydrogels for Wearable Sensors

Area of Science:

• Materials Science
• Polymer Chemistry
• Wearable Technology

Background:

• Natural polymer hydrogels are promising for wearable sensors but require enhanced mechanical and electrical properties.
• Improving stretchability, strain sensitivity, and ionic conductivity is crucial for practical applications.

Purpose of the Study:

• To develop highly stretchable, strain-sensitive, and ionic-conductive cellulose-based hydrogels (CHs).
• To evaluate the performance of these CHs for wearable sensor applications, specifically for detecting human movements.

Main Methods:

• Synthesized cellulose-based hydrogels (CHs) via random copolymerization of allyl cellulose and acrylic acid.
• Characterized hydrogel properties including stretchability, transparency, strain sensitivity, and ionic conductivity.
• Fabricated and tested hydrogel-based wearable sensors for human movement detection.

Main Results:

• Achieved highly stretchable hydrogels with ~142% tensile strain and good transparency (~86% at 550 nm).
• Demonstrated superior strain sensitivity over a wide linear range (0%-100%) with excellent signal repeatability and stability (>1000 cycles).
• Successfully constructed wearable sensors capable of detecting human movements.

Conclusions:

• Cellulose-based hydrogels (CHs) exhibit excellent mechanical, electrical, and sensing properties.
• The developed CHs show great potential for diverse applications in reliable and sensitive wearable sensors.
• This work advances the use of natural polymers in high-performance wearable electronic devices.