Dynamical structure of entangled polymers simulated under shear flow
arXiv:1703.10946 · doi:10.1063/1.5035170
Abstract
The non-linear response of entangled polymers to shear flow is complicated. Its current understanding is framed mainly as a rheological description in terms of the complex viscosity. However, the full picture requires an assessment of the dynamical structure of individual polymer chains which give rise to the macroscopic observables. Here we shed new light on this problem, using a computer simulation based on a blob model, extended to describe shear flow in polymer melts and semi-dilute solutions. We examine the diffusion and the intermediate scattering spectra during a steady shear flow. The relaxation dynamics are found to speed up along the flow direction, but slow down along the shear gradient direction. The third axis, vorticity, shows a slowdown at the short scale of a tube, but reaches a net speedup at the large scale of the chain radius of gyration.
References in corpus (8)
- Accurate effective pair potentials for polymer solutions
- Rheology of Ring Polymer Melts: From Linear Contaminants to Ring/Linear Blends
- Systematic time-scale-bridging molecular dynamics applied to flowing polymer melts
- Fingerprinting molecular relaxation in deformed polymers
- Polymer brush collapse under shear flow
- Detailed analysis of Rouse mode and dynamic scattering function of highly entangled polymer melts in equilibrium
- Implementation of Lees-Edwards periodic boundary conditions for direct numerical simulations of particle dispersions under shear flow
- Simulation of Entangled Polymer Solutions