A Monte Carlo Study of Equilibrium Polymers in a Shear Flow

TL;DR

This study uses Monte Carlo simulations to analyze how equilibrium polymers behave under shear flow, revealing elongation in flow direction, decreased average length with higher shear, and changes in molecular weight distribution.

Contribution

It introduces a microscopic off-lattice model to investigate the conformational and distributional changes of equilibrium polymers under shear flow.

Findings

Polymer chains elongate along the flow direction.

Average polymer length decreases as shear rate increases.

Molecular weight distribution shifts from Schwartz to exponential in dilute solutions.

Abstract

We use an off-lattice microscopic model for solutions of equilibrium polymers (EP) in a lamellar shear flow generated by means of a self-consistent external field between parallel hard walls. The individual conformations of the chains are found to elongate in flow direction and shrink perpendicular to it while the average polymer length decreases with increasing shear rate. The Molecular Weight Distribution of the chain lengths retains largely its exponential form in dense solutions whereas in dilute solutions it changes from a power-exponential Schwartz distribution to a purely exponential one upon an increase of the shear rate.