A Topologically Driven Glass in Ring Polymers

TL;DR

This paper uncovers a new type of glass transition in ring polymers driven by topological constraints, revealing how interpenetration and pinning induce kinetic arrest above traditional glass transition temperatures.

Contribution

It introduces a novel topologically-induced glass transition in ring polymers, highlighting the role of topological interactions and pinning in their dynamics.

Findings

Inter-ring penetrations are long-lived.

A kinetically arrested state can be induced by pinning.

The transition occurs above the classical glass transition temperature.

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.