Theory of Thermodynamic Stresses in Colloidal Dispersions at the Glass Transition

TL;DR

This paper develops a first principles theoretical framework to understand the nonlinear rheology and thermodynamic stresses in dense colloidal dispersions near the glass transition, explaining experimental flow behaviors.

Contribution

It introduces a novel first principles approach to model nonlinear rheology in colloidal glasses, neglecting hydrodynamics but capturing flow curves and Herschel Bulkley exponents.

Findings

Steady state flow curves match experimental data for dense suspensions.

Herschel Bulkley law exponents are computed for hard sphere models.

Theoretical predictions align with observed rheological behaviors.

Abstract

We discuss the nonlinear rheology of dense colloidal dispersions at the glass transition. A first principles approach starting with interacting Brownian particles in given arbitrary homogeneous (incompressible) flow neglecting hydrodynamic interactions is sketched. It e.g. explains steady state flow curves for finite shear rates measured in dense suspensions of thermosensitive core-shell particles consisting of a polystyrene core and a crosslinked poly(N-isopropylacrylamide)(PNIPAM) shell. The exponents of simple and generalized Herschel Bulkley laws are computed for hard spheres.