Depletion interactions of non-spherical colloidal particles in polymer solutions

TL;DR

This paper calculates how non-spherical colloidal particles interact in polymer solutions, focusing on anisotropic shapes like dumbbells and lenses, using exact methods for ideal polymer chains.

Contribution

It provides the first detailed calculations of orientation-dependent depletion interactions for specific non-spherical colloids in polymer solutions.

Findings

Interaction parameters for dumbbell-shaped particles derived

Interaction parameters for lens-shaped particles derived

Exact results obtained for ideal polymer chains

Abstract

We consider anisotropic colloidal particles immersed in a solution of long, flexible, and nonadsorbing polymers. For the dumbbell shapes of recently synthesized particles consisting of two intersecting spheres and for lens-shaped particles with spherical surfaces we calculate the isotropic and anisotropic interaction parameters that determine the immersion free energy and the orientation-dependent depletion interaction between particles that are induced by the polymers. Exact results are obtained for random-walk like (ideal) polymer chains.