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arXiv · 2204.02459

Deviatoric Stress Driven Transient Melting Below the Glass Transition Temperature in Shocked Polymers

Jalen Macatangay·Brenden W. Hamilton·Alejandro Strachan
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Abstract

The relaxation of polymers around and below their glass transition temperature is governed by a range of correlated unit processes with a wide range of timescales. The fast deformation rates of shock loading can negate a significant fraction of these processes resulting in the dynamical glass transition in rubbers. In this letter we report the inverse, a transient melting of glassy polymer under shock loading. The large deviatoric stresses near the shock front induce fast transitions in backbone dihedral angles and a stress relaxation characteristic of polymer melts. This is followed by the slower relaxation expected for glasses.

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Jalen Macatangay, Brenden W. Hamilton, Alejandro Strachan. 2022-04-05. Deviatoric Stress Driven Transient Melting Below the Glass Transition Temperature in Shocked Polymers. https://doi.org/10.1063/5.0095731

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