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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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Rational mechanochemical design of Diels–Alder crosslinked biocompatible hydrogels with enhanced properties
An important but often overlooked feature of Diels–Alder (DA) cycloadditions is the ability for DA adducts to undergo mechanically induced cycloreversion when placed under force. Herein, we demonstrate that the commonly employed DA cycloaddition between furan and maleimide to crosslink hydrogels results in slow gelation kinetics and “mechanolabile” crosslinks that relate to reduced material strength. Through rational computational design, “mechanoresistant” DA adducts were identified by constrained geometries simulate external force models and employed to enhance failure strength of crosslinked hydrogels. Additionally, utilization of a cyclopentadiene derivative, spiro[2.4]hepta-4,6-diene, provided mechanoresistant DA adducts and rapid gelation in minutes at room temperature. This study illustrates that strategic molecular-level design of DA crosslinks can provide biocompatible materials with improved processing, mechanical durability, lifetime, and utility.
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- Award ID(s):
- 1933487
- PAR ID:
- 10415543
- Date Published:
- Journal Name:
- Materials Horizons
- Volume:
- 9
- Issue:
- 7
- ISSN:
- 2051-6347
- Page Range / eLocation ID:
- 1947 to 1953
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1039/d2mh00338d
