Numerical simulation reveals shear banding dynamics in polymer melts, indicating critical entanglement thresholds for flow instabilities in physical polymers.
Key Points
Evaluate the onset of shear banding in polymer melts under shear flow by comparing numerical simulations to a theoretical model coupling tube and entanglement dynamics.
Simulated polymer melts under shear flow to determine how the convected constraint release (CCR) parameter β depends on chain bending stiffness kθ.
Evaluated predictions from a theoretical model integrating Rolie-Poly-like tube dynamics with CCR against simulation data across varying entanglement numbers.
The theoretical framework predicts shear banding when the equilibrium entanglement number Z surpasses a critical threshold Zc that depends on β.
Simulations demonstrated semiquantitative agreement with the theoretical model, with discrepancies arising from standard tube model limitations in partially disentangled regimes under strong flow.