Viscoelasticity of concentrated isotropic solutions of semiflexible polymers. 3. Nonlinear rheology

摘要

Nonlinear rheological properties of a tightly-entangled solution of persistent macromolecules are calculated within the context of a tube model. It is shown that the curvature stress in highly deformed solutions of such chains is dominated by the contributions of deformation-induced `hairpins', i.e., rare but very tightly curved segments of the deformed chain conformations. The model is found to exhibit strain softening in shear deformations.