Polymer Shape Anisotropy and the Depletion Interaction

TL;DR

This paper calculates the virial coefficients of polymer depletion interactions considering shape anisotropy, providing a theoretical framework that aligns with recent experimental observations on polymers comparable in size to colloidal particles.

Contribution

It introduces a method to incorporate polymer shape anisotropy into depletion interaction calculations, advancing the understanding of colloid-polymer systems.

Findings

Virial coefficients depend on polymer anisotropy.

Theoretical results align with recent experiments.

Polymer shape significantly influences depletion forces.

Abstract

We calculate the second and third virial coefficients of the effective sphere-sphere interaction due to polymer depletion. By utilizing the anisotropy of a typical polymer conformation, we can consider polymers that are roughly the same size as the spherical inclusions. We argue that recent experiments can confirm this anisotropy.