Microfluidic rheology of soft colloids above and below jamming

Abstract

The rheology near jamming of a suspension of soft colloidal spheres is studied using a custom microfluidic rheometer that provides stress versus strain rate over many decades. We find non-Newtonian behavior below the jamming concentration and yield stress behavior above it. The data may be collapsed onto two branches with critical scaling exponents that agree with expectations based on Hertzian contacts and viscous drag. These results support the conclusion that jamming is similar to a critical phase transition, but with interaction-dependent exponents.

4 pages, experiment

References in corpus (5)

• Jamming at Zero Temperature and Zero Applied Stress: the Epitome of Disorder
• Critical scaling in linear response of frictionless granular packings near jamming
• Scaling properties of granular rheology near the jamming transition
• Rate Dependence and Role of Disorder in Linearly Sheared Two-Dimensional Foams
• Centrifugal compression of soft particle packings - theory and experiment