Healable Ionoelastomer Designed from Polymeric Ionic Liquid and Vitrimer Chemistry

Area of Science:

• Materials Science
• Polymer Chemistry
• Solid-State Ionics

Background:

• Increasing demand for flexible, stretchable, and wearable devices necessitates advanced ionoelastomers.
• Existing ionoelastomers face durability challenges due to repeated deformations.
• Incorporating self-healing capabilities is crucial for improving material longevity.

Purpose of the Study:

• To synthesize and characterize novel polymeric ionic liquid (PIL) networks with enhanced durability.
• To impart self-healing and recyclability properties to ionoelastomers for advanced applications.
• To investigate the relationship between material composition and performance characteristics.

Main Methods:

• Synthesis of an allyl-functionalized PIL via quaternization of N-allylimidazole with a poly(epichlorohydrin)-poly(ethylene oxide) copolymer.
• Cross-linking of the PIL using dynamic boronic ester cross-linkers (BDB) via thiol-ene click photoaddition.
• Incorporation of poly(ethylene oxide) (PEO) dangling chains as free volume enhancers.

Main Results:

• Optimized PIL networks exhibited desirable properties: soft (0.2 MPa), stretchable (300%), and highly conductive (1.6 × 10⁻⁵ S·cm⁻¹ at 30 °C).
• The dynamic boronic ester cross-linkers enabled vitrimer behavior, including self-healing and recyclability.
• Recycled materials maintained original mechanical properties and ionic conductivity.

Conclusions:

• The developed healable PIL networks offer a promising solution for durable, high-performance solid electrolytes.
• These materials are suitable for applications requiring ionic conductivity, self-healing, and reprocessability.
• The study highlights the potential of dynamic cross-linking strategies for advanced functional materials.