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  • Glass‐transition temperature governs the thermal decrosslinking behavior of Diels–Alder crosslinked polymethacrylate networks
Title: Glass‐transition temperature governs the thermal decrosslinking behavior of Diels–Alder crosslinked polymethacrylate networks
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  more » « less
Award ID(s):
1904631
PAR ID:
10457576
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Polymer Science
Volume:
58
Issue:
1
ISSN:
2642-4150
Page Range / eLocation ID:
p. 193-203
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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