Shear Thickening behavior of anisotropic system
Suspensions containing anisotropic particles, such as clays, pigments and inorganic mineral crystals have significant importance in the formulation of chemicals, pharmaceuticals, paints, and coatings. Concentrated anisotropic particle suspensions can exhibit non-Newtonian rheological behaviors similar to those observed in concentrated spherical particle suspensions, including reversible shear thinning and shear thickening, yielding behavior and thixotropy. The purpose of our research is to quantify the effects of particle shape on the rheology of colloidal dispersions, with particular emphasis on the shear thickening behavior. Experiments and modeling on model systems will extend our understanding of the flow behavior and test existing theories concerning the mechanism of shear thickening in concentrated colloidal suspensions.
In this project, we will synthesize a model anisotropic particle suspension with low polydispersity to explore the rheology and microstructure evolution during shear thickening in anisotropic particle suspensions. New methods combining rheology with small angle neutron scattering (rheo-SANS) will enable quantifying the flow-induced alignment and other microstructural changes associated with the rheological response. The results of these fundamental studies will be applied to engineer advanced nanocomposites containing STFs for applications in protective materials