Aspects of the Plastic Deformation in Glassy Polymer Blends

This paper reports on a micromechanical study of plastic deformation (‘shear yielding’) in amorphous polymer-rubber blends after the rubber particles have cavitated. Unit cell analyses are carried out under plane strain or under axisymmetric conditions, for the growth of the resulting voids by rate-dependent plastic flow in the matrix. The material model accounts for the intrinsic strain softening upon yield and the subsequent orientational strain hardening that is typical for ‘shear yielding’ in amorphous polymers. Numerical, finite strain simulations demonstrate how this typical constitutive behaviour gives rise to a peculiar way of growth of these voids, which at least qualitatively seems to agree with experimental observations.