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arXiv · 1308.1317

Nonlinear mechanics of thermoreversibly associating dendrimer glasses

Arvind Srikanth·Robert S. Hoy·Berend C. Rinderspacher·Jan W. Andzelm
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Abstract

We model the mechanics of associating trivalent dendrimer network glasses with a focus on their energy dissipation properties. Various combinations of sticky bond (SB) strength and kinetics are employed. The toughness (work-to-fracture) of these systems displays a surprising deformation-protocol dependence; different association parameters optimize different properties. In particular, "strong, slow" SBs optimize strength, while "weak, fast" SBs optimize ductility via self-healing during deformation. We relate these observations to breaking, reformation, and partner-switching of SBs during deformation. These studies point the way to creating associating-polymer network glasses with tailorable mechanical properties.

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Arvind Srikanth, Robert S. Hoy, Berend C. Rinderspacher, Jan W. Andzelm. 2013-08-06. Nonlinear mechanics of thermoreversibly associating dendrimer glasses. https://doi.org/10.1103/physreve.88.042607

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