Highly stretchable, self-healable and adhesive, thermal responsive conductive hydrogel loading nanocellulose complex...

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Flexible conductive hydrogels are crucial for wearable electronics, electronic skin, and health monitoring.
• Developing hydrogels with both superior mechanical properties (stretchability, compressibility) and high conductivity remains a significant challenge.

Purpose of the Study:

• To create a novel flexible conductive hydrogel with enhanced mechanical performance, conductivity, and self-healing capabilities.
• To investigate the synergistic effects of dynamic hydrogen bonds, metal coordination bonds, and decorated cellulose nanofibers on hydrogel properties.

Main Methods:

• Free radical polymerization was used to synthesize polyvinyl alcohol (PVA)/poly (2-hydroxyethyl methacrylate) (PHEMA) hydrogels.
• Polypyrrole-decorated cellulose nanofibers (CNFs@PPy) were incorporated to enhance mechanical and conductive properties.
• The hydrogels were characterized for mechanical strength, stretchability, conductivity, self-healing, adhesion, and strain sensing capabilities.

Main Results:

• The developed hydrogels exhibit super-stretchability (approx. 2600% elongation), excellent toughness (2.74 MJ/m³), and strong compressive strength (1.96 MPa).
• The nanocomposite hydrogels demonstrate fast temperature responsiveness, outstanding strain sensing (GF = 3.13), rapid self-healing, and strong adhesion to various surfaces.
• High stability and repeatability in pressure and strain sensing were observed across a wide deformation range.

Conclusions:

• The synergistic combination of dynamic bonds and CNFs@PPy significantly improves hydrogel performance.
• These advanced hydrogels are promising candidates for applications in motion monitoring, wearable electronics, and healthcare management due to their robust and versatile properties.