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Dynamic polymers with remarkable energy dissipation and dampening are highly sought after for advanced applications. Here, spring-like aromatic foldamers were incorporated into the backbones of polymer networks crosslinked with dynamic Diels-Alder (DA) adducts or non-dynamic static crosslinkers. Improved mechanical, self-healing and dampening properties were found in networks with shorter chains, more aromatic stacked foldamer units and dynamic DA adduct crosslinks. These enhanced properties were attributed to the synergistic effects of the reversible elastic response to stress of spring-like aromatic foldamers and the DA adducts.
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Aromatic foldamers as molecular springs in network polymers
Polymer networks crosslinked with spring-like ortho -phenylene ( o P) foldamers were developed. NMR analysis indicated the o P crosslinkers were well-folded. Polymer networks with o P-based crosslinkers showed enhanced energy dissipation and elasticity compared to divinylbenzene crosslinked networks. The energy dissipation was attributed to the strain-induced reversible unfolding of the o P units. Energy dissipation increased with the number of helical turns in the foldamer.
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- PAR ID:
- 10347899
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 58
- Issue:
- 37
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 5590 to 5593
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1039/D2CC01223E
