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.
Ionic mobility driven by correlated van der Waals and electrostatic forces
Classical theories of dielectric friction make two critical assumptions: (i) friction due to van der Waals (vdW) forces is described by hydrodynamic drag and is independent of the ionic charge and (ii) vdW and electrostatic forces are statistically independent. Both assumptions turn out to be incorrect when tested against simulations of anions and cations with varying charge magnitude dissolved in water. Both the vdW and electrostatic components of the force variance scale linearly with the ionic charge squared. The two components are strongly anticorrelated producing simple relations for the total force variance in terms of self-variances. The inverse diffusion constant scales linearly with the charge squared. Solvation asymmetry between cations and anions extends to linear transport coefficients.
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- Award ID(s):
- 2154465
- NSF-PAR ID:
- 10399490
- Date Published:
- Journal Name:
- The Journal of Chemical Physics
- Volume:
- 156
- Issue:
- 20
- ISSN:
- 0021-9606
- Page Range / eLocation ID:
- 204501
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract -
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/5.0088835
