How long does it take to pull an ideal polymer into a small hole?

TL;DR

This paper derives scaling laws for the time it takes to pull ideal linear and branched polymers into a small hole under force, supported by molecular dynamics simulations.

Contribution

It introduces new scaling estimates for absorption times of ideal polymers into small holes, considering their linear and branched structures.

Findings

Scaling laws: τ_lin ~ N^{3/2}/f and τ_br ~ N^{5/4}/f.

Sequential straightening of polymer folds governs absorption.

Molecular dynamics simulations confirm the theoretical predictions.

Abstract

We present scaling estimates for characteristic times $\tau_{\rm lin}$ and $\tau_{\rm br}$ of pulling ideal linear and randomly branched polymers of $N$ monomers into a small hole by a force $f$. We show that the absorbtion process develops as sequential straightening of folds of the initial polymer configuration. By estimating the typical size of the fold involved into the motion, we arrive at the following predictions: $\tau_{\rm lin}(N) \sim N^{3/2}/f$ and $\tau_{\rm br}(N) \sim N^{5/4}/f$, and we also confirm them by the molecular dynamics experiment.