RHEOLOGY OF CONCENTRATED SUSPENSIONS - EXPERIMENTAL INVESTIGATIONS

The experimental work in suspension rheology has developed in parallel with the theoretical progress which has been recently made in this field. Here, rheological measurements are applied to investigate some of the parameters that affect the flow of concentrated suspensions of colloidal particles. Steady-state shear flow and oscillatory shear flow are studied as well as transient measurements. The data provide information about the microstructure of the suspension. This is illustrated for sterically stabilized colloidal suspensions. The particle size ranges from 100 to 1000 nm, while the thickness of the deformable stabilizer layer is kept approximately constant. As a result, the different particle sizes give particles of varying apparent softness. Their rheological behaviour at high volume fractions is studied. The experimental results are compared with recent theoretical predictions of microstructure using simulations derived from non-equilibrium molecular dynamics. © 1987.