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arXiv · cond-mat/0506737

Shear-induced overaging in a polymer glass

Matthew L. Wallace·Bela Joos
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Abstract

A phenomenon recently coined as ``overaging'' implies a slowdown in the collective (slow) relaxation modes of a glass when a transient shear strain is imposed. We are able to reproduce this behavior in simulations of a supercooled polymer melt by imposing instantaneous shear deformations. The increases in relaxation times $Δτ_{1/2}$ rise rapidly with deformation, becoming exponential in the plastic regime. This ``overaging'' is distinct from standard aging. We find increases in pressure, bond-orientational order and in the average energy of the inherent structures ($ $) of the system, all dependent on the size of the deformation. The observed change in behavior from elastic to plastic deformation suggests a link to the physics of the ``jammed state''

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Matthew L. Wallace, Bela Joos. 2005-06-28. Shear-induced overaging in a polymer glass. https://doi.org/10.1103/physrevlett.96.025501

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