Anisotropic plastic deformation of glassy polymers with process-induced molecular orientation

Buckley, C.P.; Wu, J.J.

Abstract

The constitutive modelling of glassy thermoplastics is extended to the case of anisotropy arising from processinduced molecular orientation. The basis of the work is the Glass-Rubber model framework, known to capture well the constitutive response of isotropic amorphous polymers on either side of the glass transition. The key feature of the new model is that the thermally-activated diffusion event is recognised as being intrinsically anisotropic. Melt-process history establishes an orientation distribution for the relaxing units. In modelling subsequent deformation below Tg the stress is integrated over this distribution. The model naturally exhibits many aspects of behaviour seen experimentally: increase of yield stress, apparent reduction of activation volume and increasing strain-stiffening with increasing orientation.

• Presentation Conference Type: Conference Paper (Published)
• Conference Name: 19th Annual Meeting of the Polymer Processing Society
• Publication Date: 2003-07
• Public URL: https://durham-repository.worktribe.com/output/1163170
• Additional Information: Presented at the 19th Annual Meeting of the Polymer Processing Society, Melbourne, 7-10 July 2003.