Glass transitions and shear thickening suspension rheology

Glass transitions and shear thickening suspension rheology

We introduce a class of simple models for shear thickening and/or ‘‘jamming’’ in colloidal suspensions. These are based on the schematic mode coupling theory ~MCT! of the glass transition, having a memory term that depends on a density variable, and on both the shear stress and the shear rate. ~Tensorial aspects of the rheology, such as normal stresses, are ignored for simplicity.! We calculate...

Rheology and Microstructure of Shear Thickening Fluid Suspoemulsions

A novel shear thickening suspoemulsion is formulated and studied with a new rheo-microscope instrument. The experimental fluid system is comprised of a immiscible blend of Newtonian, low molecular weight poly(dimethylsiloxane) and a shear thickening suspension of colloidal silica in poly(ethylene glycol). The blend is studied as a function of composition where phase inversion is evident at low ...

Microstructure and Rheology Relationships for Shear Thickening Colloidal Dispersions

The non-Newtonian shear rheology of colloidal dispersions is the result of the competition and balance between hydrodynamic (dissipative) and thermodynamic (conservative) forces that lead to a nonequilibrium microstructure under flow. We present the first experimental measurements of the shear induced microstructure of a concentrated, near hard-sphere colloidal dispersion through the shear thic...

Suspension rheology under oscillatory shear and its geophysical implications

Probing hydrogen bond interactions in a shear thickening polysaccharide using nonlinear shear and extensional rheology.

Mamaku gum is a polysaccharide extracted from the fronds of the black tree fern found in New Zealand. The cooked pith has traditionally been used for various medicinal purposes and as a food source by the Maori people of New Zealand. It has potential applications as a thickener in the food industry and as a palliative for patients with dysphagia. Studies on the shear rheology of Mamaku gum have...