Electrically accelerated self‐healable poly(ionic liquids) copolymers that exhibit resistor‐capacitor (RC) circuit properties are developed. At low alternating current (AC) frequencies these materials behave as a resistor (R), whereas at higher frequencies as a capacitor (C). These properties are attributed to a combination of dipolar and electrostatic interactions in (1‐[(2‐methacryloyloxy)ethyl]‐3‐butylimidazolium bis(trifluoromethyl‐sulfonyl)imide) copolymerized with methyl methacrylate (MMA) monomers to form p(MEBIm‐TSFI/MMA)] copolymers. When the monomer molar ratio (MEBIm‐TSFI:MMA) is 40/60, these copolymers are capable of undergoing multiple damage‐repair cycles and self‐healing is accelerated by the application of alternating 1.0–4.0 V electric field (EF). Self‐healing in the absence of EFs is facilitated by van der Waals (vdW) interactions, but the application of AC EF induces back and forth movement of charges against the opposing force that result in dithering of electrostatic dipoles giving rise to interchain physical crosslinks. Electrostatic inter‐ and intrachain interactions facilitated by copolymerization of ionic liquid monomers with typically dielectric acrylic‐based monomers result in enhanced cohesive energy densities that accelerate the recovery of vdW forces facilitating self‐healing. Incorporating ionic liquids into commodity polymers offers promising uses as green conducting solid polyelectrolytes in self‐healable energy storage, energy‐harvesting devices, and many other applications.
- Award ID(s):
- 1719875
- NSF-PAR ID:
- 10411558
- Date Published:
- Journal Name:
- Soft Matter
- Volume:
- 18
- Issue:
- 39
- ISSN:
- 1744-683X
- Page Range / eLocation ID:
- 7679 to 7688
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2SM00755J
