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ABSTRACT A series of Diels–Alder (DA) crosslinked polymethacrylate networks covering a broad range of glass‐transition temperatures (Tg) was prepared to establish the relationship between theTgand the thermal decrosslinking behavior of these networks. A series of permanently crosslinked and uncrosslinked analogues were also prepared to better understand the thermoset‐to‐thermoplastic transition occurring in the DA networks at elevated temperatures. The network series were studied using dynamic mechanical analysis, which established an inverse relationship betweenTgand decrosslinking ability. Differential scanning calorimetry confirmed the viability of the DA linkages in all formulations, and a trapping experiment with 9‐anthracenemethanol demonstrated that even the least responsive network was capable of undergoing decrosslinking given appropriate thermal treatment. While polymer chain mobility has long been understood to be a critical factor in healable materials, this work verifies the importance of this parameter in the decrosslinking of DA networks. © 2019 Wiley Periodicals, Inc. J. Polym. Sci.2020,58, 193–203
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This content will become publicly available on April 25, 2026
Viscoelastic Supramolecular Networks Based on Guanidinium‐Oxyanion Interactions
ABSTRACT We describe the synthesis and characterization of supramolecular networks based on charge‐assisted hydrogen bonding interactions of guanidinium and oxyanion functionalities. Although they are constructed entirely of small‐molecule components, these materials display properties such as a glass transition and time‐ and temperature‐dependent viscoelastic rheological behavior. These properties can be tuned by the choice of each network component:Tgvaries by over 50°C in the studied networks, and relaxation times scaled with changes toTg. However, these supramolecular materials are inherently degradable and thermally reversible as no covalent macromolecular structure is formed.
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- Award ID(s):
- 2105149
- PAR ID:
- 10585333
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science
- Volume:
- 63
- Issue:
- 11
- ISSN:
- 2642-4150
- Format(s):
- Medium: X Size: p. 2363-2370
- Size(s):
- p. 2363-2370
- Sponsoring Org:
- National Science Foundation
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