Preaveraging description of polymer nonequilibrium stretching

TL;DR

This paper develops a preaveraging approach combined with mode analysis to simplify the modeling of polymer stretching from equilibrium to nonequilibrium steady states, accounting for long-range interactions and transient regime evolution.

Contribution

It introduces a novel preaveraging method that captures the transient and steady-state behaviors of polymers under nonequilibrium stretching, including hierarchical regime evolution.

Findings

Preaveraging simplifies Langevin equations for polymer stretching.

Transient regime structure evolves hierarchically during stretching.

Method accounts for long-range self-avoiding interactions.

Abstract

This article focuses on a preaveraging description of polymer nonequilibrium stretching, where a single polymer undergoes a transient process from equilibrium to nonequilibrium steady state by pulling one chain end. The preaveraging method combined with mode analysis reduces the original Langevin equation to a simplified form for both a stretched steady state and an equilibrium state, even in the presence of self-avoiding repulsive interactions spanning a long range. However, the transient stretching process exhibits evolution of a hierarchal regime structure, which means a qualitative temporal change in probabilistic distributions assumed in preaveraging. We investigate the preaveraging method for evolution of the regime structure with consideration of the nonequilibrium work relations and deviations from the fluctuation-dissipation relation.