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arXiv · 1110.4028

A Simple Model for the Deformation-Induced Relaxation of Glassy Polymers

S. M. Fielding·R. G. Larson·M. E. Cates
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Abstract

Glassy polymers show strain hardening: at constant extensional load, their flow first accelerates, then arrests. Recent experiments have found this to be accompanied by a striking and unexplained dip in the segmental relaxation time. Here we explain such behavior by combining a minimal model of flow-induced liquefaction of a glass, with a description of the stress carried by strained polymers, creating a non-factorable interplay between aging and strain-induced rejuvenation. Under constant load, liquefaction of segmental motion permits strong flow that creates polymer-borne stress. This slows the deformation enough for the segmental modes to re-vitrify, causing strain hardening.

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S. M. Fielding, R. G. Larson, M. E. Cates. 2011-10-18. A Simple Model for the Deformation-Induced Relaxation of Glassy Polymers. https://doi.org/10.1103/physrevlett.108.048301

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