Tube width fluctuations of entangled stiff polymers

TL;DR

This paper develops a theoretical framework to explain spatial heterogeneities in the tube-like cages of entangled stiff polymers, predicting the distribution of tube radius fluctuations with good experimental and simulation agreement.

Contribution

It introduces a systematic theory extending Morse's work, using a local binary collision approximation to predict tube radius fluctuations in entangled stiff polymers.

Findings

Derived a distribution function for tube radius fluctuations.

Predicted a universal scaling function for the tube radius distribution.

Achieved good agreement with experimental and simulation data.

Abstract

The tube-like cages of stiff polymers in entangled solutions have been shown to exhibit characteristic spatial heterogeneities. We explain these observations by a systematic theory generalizing previous work by D. Morse (Phys. Rev. E 63:031502, 2001). With a local version of the binary collision approximation (BCA), the distribution of confinement strengths is calculated, and the magnitude and the distribution function of tube radius fluctuations are predicted. Our main result is a unique scaling function for the tube radius distribution, in good agreement with experimental and simulation data.