Investigating the microstructure of a yield-stress fluid by light scattering

D. Lee , I.A. Gutowski , A.E. Bailey , L. Rubatat (1) , J.R. de Bruyn , B.J. Frisken

1 IPREM - Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux

We report the results of an experimental study of the microstructure of dispersions of Carbopol ETD 2050, a model yield-stress fluid. Using two different light scattering instruments, measurements were made over three decades in scattering wave vector, from 0.02 to 25 μm-1. These measurements reveal microstructure characterized by two length scales: a longer length scale, 6μm and larger, that depends on Carbopol concentration and the pH of the dispersion and a shorter length scale of approximately 400 nm that is independent of both sample concentration and pH. We relate these results to shear rheology measurement of the yield stress of these materials. © 2011 American Physical Society.

Domains: Physics [physics]

D. Lee, I.A. Gutowski, A.E. Bailey, L. Rubatat, J.R. de Bruyn, et al.. Investigating the microstructure of a yield-stress fluid by light scattering. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2011, 83 (3), ⟨10.1103/PhysRevE.83.031401⟩. ⟨hal-01560395⟩