Propagation of Tension along a Polymer Chain

TL;DR

This paper investigates how tension propagates along long polymer chains under external forces, revealing a diffusive $t^{1/2}$ propagation pattern in different configurations, supported by numerical and molecular dynamics simulations.

Contribution

It demonstrates that tension propagation in polymers follows a diffusion equation and compares different geometries and translocation scenarios.

Findings

Tension front propagates as $t^{1/2}$ along the chain.

Propagation is governed by a diffusion equation.

Tension propagation is slower during translocation.

Abstract

We study the propagation of tension caused by an external force along a long polymeric molecule in two different settings, namely along a free polymer in 3d space being pulled from one end, and along a pre-stretched circular polymer, confined in a narrow circular tube. We show that in both cases, the tension propagation is governed by a diffusion equation, and in particular, the tension front propagates as $t^{1/2}$ along the contour of the chain. The results are confirmed numerically, and by molecular dynamics simulations in the case of the 3d polymer. We also compare our results with the previously suggested ones for the translocation setting, and discuss why tension propagation is slower in that case.