Healable thermoset polymer composite embedded with stimuli-responsive fibres

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Macroscopic damage in thermoset polymer composites requires closure for healing, similar to biological systems.
• Stimuli-responsive shape-changing polymeric fibers offer potential for automatic crack closure upon stimulation.
• Existing self-healing materials often face challenges in efficiently closing and bonding macroscopic damage.

Purpose of the Study:

• To develop a stimuli-responsive fiber (SRF) with supercontraction capability for healing macroscopic damage in polymer composites.
• To integrate SRFs and thermoplastic particles (TPs) into epoxy for a repeatable, biomimetic self-healing system.
• To evaluate the healing efficiency and repeatability of the developed self-healing system.

Main Methods:

• Fabrication of stimuli-responsive fibers (SRFs) with supercontraction properties.
• Incorporation of SRFs and thermoplastic particles (TPs) into a thermosetting epoxy matrix.
• Testing of healing efficiency using tapered double-cantilever beam specimens under thermal stimulation.

Main Results:

• A stimuli-responsive fiber (SRF) with supercontraction capability was successfully fabricated.
• The composite system demonstrated effective crack closure via thermal-induced SRF supercontraction.
• The melting and diffusion of TPs at the crack interface facilitated bonding, achieving 94% healing efficiency.
• The self-healing process exhibited reasonable repeatability.

Conclusions:

• The developed self-healing system effectively mimics biological healing by closing and bonding macroscopic cracks.
• Stimuli-responsive fibers and thermoplastic particles offer a promising approach for advanced self-healing polymer composites.
• The high healing efficiency and repeatability suggest practical applications for this technology.