A microscopic view of accelerated dynamics in deformed polymer glasses

Mya Warren; Joerg Rottler

doi:10.1103/physrevlett.104.205501

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arXiv · 1002.1930

A microscopic view of accelerated dynamics in deformed polymer glasses

Mya Warren·Joerg Rottler

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Abstract

A molecular level analysis of segmental trajectories obtained from molecular dynamics simulations is used to obtain the full relaxation time spectrum in aging polymer glasses subject to three different deformation protocols. As in experiments, dynamics can be accelerated by several orders of magnitude, and a narrowing of the distribution of relaxation times during creep is directly observed. Additionally, the acceleration factor describing the transformation of the relaxation time distributions is computed and found to obey a universal dependence on the global strain, independent of age and deformation protocol.

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Mya Warren, Joerg Rottler. 2010-08-16. A microscopic view of accelerated dynamics in deformed polymer glasses. https://doi.org/10.1103/physrevlett.104.205501

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