Chain retraction in highly entangled stretched polymer melts

Abstract

We use computer simulations to study the relaxation of strongly deformed highly entangled polymer melts in the non-linear viscoelastic regime, focusing on anisotropic chain conformations after isochoric elongation. The Doi-Edwards tube model and its GLaMM extension, incorporating contour length fluctuation and convective constraint release, predict a retraction of the polymer chain extension in all directions, setting in immediately after deformation. This prediction has been challenged by experiment, simulation, and other theoretical studies, questioning the general validity of the tube concept. For very long chains we observe the initial contraction of the chain extension parallel and perpendicular to the stretching direction. However, the effect is significantly weaker than predicted by the GLaMM model. We also show that the first anisotropic term of an expansion of the 2D scattering function qualitatively agrees to predictions of the GLaMM model, providing an option for direct experimental tests.

6 pages, 3 figures, 7 references added

References in corpus (5)

• Static and dynamic properties of large polymer melts in equilibrium
• Equilibration of High Molecular-Weight Polymer Melts: A Hierarchical Strategy
• Fingerprinting molecular relaxation in deformed polymers
• Detailed analysis of Rouse mode and dynamic scattering function of highly entangled polymer melts in equilibrium
• Chain retraction in highly entangled stretched polymer melts

Cited by in corpus (4)

• Optical tweezers microrheology maps the dynamics of strain-induced local inhomogeneities in entangled polymers
• Clustering of entanglement points in highly strained polymer melts
• Chain retraction in highly entangled stretched polymer melts
• Glass transition temperature of thin polymer films