Aggregation and Rheology of Concentrated Mineral Suspensions
Suspension rheology plays a significant role in a wide variety of industries and applications: mineral processing, construction materials, paints and coatings, and drug delivery, for example. Although advances in the science of suspension rheology have been made consistently for centuries, many systems exist for which their rheological behavior is inadequately described by existing generalized models. Two systems are considered which display unexpected rheological behavior: the first is a model system of glass spheres in a polymeric fluid, and the second is a real system of irregularly shaped portlandite particles in aqueous suspension with added polymer dispersants. A thorough examination of the aggregation behavior of both systems, through analysis of rheometric experiments and secondary techniques such as light scattering, reveals details of interparticle interactions and aggregation/dispersion mechanisms which may be overlooked by simplified models. These findings advance the ability to tailor suspensions with anomalous behavior to desired rheological properties.