Nonlinear rheologyof colloidal dispersions

Abstract

Colloidal dispersions are commonly encountered in everyday life and represent an important class of complex fuid. Of particular sign if cance for many commercial products and industrial processes is the ability to control and manipulate the macroscopic f ow response of a dispersion by tuning the microscopic interactions between the constituents. An important step towards<br />attaining this goal is the development of robust theoretical methods for predicting from frist-principles the rheology and nonequilibrium microstructure of well defned model systems subject to external f ow. In this review we give an ovelview of some promising theoretical approaches and the phenomena they seek to describe, focusing, for simplicity, on systems for which the colloidal particles interact via strongly repulsive, spherically symmetric nteractions.In presenting the various theories, we will consider frst low volume fraction systems, for which a number of exact results may be derived, before moving on to consider the intennediate and high volume fraction states which present both the most interesting physics and the most demanding technical challenges. In the high volume fraction regime particular emphasis will be given to the rheology of dynamically arrested states.