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arXiv · 1510.05625

A Topologically Driven Glass in Ring Polymers

Davide Michieletto·Matthew S. Turner
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Abstract

The static and dynamic properties of ring polymers in concentrated solutions remains one of the last deep unsolved questions in Polymer Physics. At the same time, the nature of the glass transition in polymeric systems is also not well understood. In this work we study a novel glass transition in systems made of circular polymers by exploiting the topological constraints that are conjectured to populate concentrated solutions of rings. We show that such rings strongly inter-penetrate through one another, generating an extensive network of topological interactions that dramatically affects their dynamics. We show that a kinetically arrested state can be induced by randomly pinning a small fraction of the rings. This occurs well above the classical glass transition temperature at which microscopic mobility is lost. Our work demonstrates both the existence of long-lived inter-ring penetrations and also realises a novel, topologically-induced, glass transition.

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Davide Michieletto, Matthew S. Turner. 2016-03-31. A Topologically Driven Glass in Ring Polymers. https://doi.org/10.1073/pnas.1520665113

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