Prestrain-Enabled Stretchable and Conductive Aerogel Fibers

Area of Science:

• Materials Science
• Nanotechnology
• Polymer Science

Background:

• Aerogels possess desirable properties like ultralow density and high surface area.
• However, their inherent brittleness limits their application in flexible and wearable electronics.

Purpose of the Study:

• To engineer highly stretchable conductive aerogel fibers.
• To overcome the limitations of brittle aerogels for integration into wearable devices.

Main Methods:

• A prestrain-enabled coaxial architecture using a thermoplastic elastomer (TPE) sheath and a buckled aerogel core was developed.
• Wet-spinning with a sacrificial lignin template and subsequent infusion, freezing, and lyophilization of conductive precursors were employed.
• Releasing prestretch programmed the aerogel core for controlled unfolding during elongation.

Main Results:

• The TPE-wrapped aerogel fibers demonstrated reversible elongation up to 250% while maintaining electrical conductivity.
• Stable and small resistance changes (<0.04) were observed at low strains (<60%), with monotonic and recoverable responses at larger strains.
• A strain-dependent percolation model explained the electrical signal behavior.

Conclusions:

• This strategy successfully decouples elasticity from conductivity in aerogel fibers.
• The developed method provides a scalable route to ultralight, encapsulated, and skin-compatible aerogel fibers.
• These fibers are suitable for smart textiles and deformable electronic applications.