Strain hardening of polycarbonate in the glassy state: Influence of temperature and molecular weight

This study is concerned with the temperature and molecular weight dependence of the strain‐hardening behavior of polycarbonate. It is shown that the strain‐hardening modulus reduces with increasing temperature and decreasing molecular weight. This result is interpreted in terms of temperature accelerated relaxation of the entanglement network. Moreover, it is shown that frozen‐in orientations, induced by homogeneous deformations above the glass transition temperature, lead to anisotropic yield behavior that can be fully rationalized (and modelled) in terms of a superimposed stress contribution of the prestrained network.