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A molecular interpretation of the toughness of multiple network elastomers at high temperature.

ABSTRACT: SignificanceSoft materials can be toughened by creating dissipative mechanisms in stretchy matrixes. Yet using them over a wide range of temperatures requires dissipative mechanisms independent of stretch rate or temperature. We show that sacrificial covalent bonds in multiple network elastomers are most useful in toughening elastomers at high temperature and act synergistically with viscoelasticity at lower temperature. We do not attribute this toughening mechanism only to the scission of bonds during crack propagation but propose that the highly stretched network diluted in a stretchy matrix acts by simultaneously stiffening the elastomer and delaying the localization of bond scission and the propagation of a crack. Such a toughening mechanism has never been proposed for elastomers and should guide network design.

SUBMITTER: Slootman J

PROVIDER: S-EPMC9060454 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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A molecular interpretation of the toughness of multiple network elastomers at high temperature.

Slootman Juliette J Yeh C Joshua CJ Millereau Pierre P Comtet Jean J Creton Costantino C

Proceedings of the National Academy of Sciences of the United States of America 20220324 13

SignificanceSoft materials can be toughened by creating dissipative mechanisms in stretchy matrixes. Yet using them over a wide range of temperatures requires dissipative mechanisms independent of stretch rate or temperature. We show that sacrificial covalent bonds in multiple network elastomers are most useful in toughening elastomers at high temperature and act synergistically with viscoelasticity at lower temperature. We do not attribute this toughening mechanism only to the scission of bonds ...[more]

PMID: 35324328

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