Strain Hardening in Polymer Glasses: Limitations of Network Models

Abstract

Simulations are used to examine the microscopic origins of strain hardening in polymer glasses. While traditional entropic network models can be fit to the total stress, their underlying assumptions are inconsistent with simulation results. There is a substantial energetic contribution to the stress that rises rapidly as segments between entanglements are pulled taut. The thermal component of stress is less sensitive to entanglements, mostly irreversible, and directly related to the rate of local plastic arrangements. Entangled and unentangled chains show the same strain hardening when plotted against the microscopic chain orientation rather than the macroscopic strain.

arXiv comment4 pages, 3 figures

References in corpus (3)

• Equilibration of Long Chain Polymer Melts in Computer Simulations
• Shear yielding of amorphous glassy solids: Effect of temperature and strain rate
• Unified Description of Aging and Rate Effects in Yield of Glassy Solids

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