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Nonlinear rheology of Laponite suspensions under an external drive

Bérengère Abou·Daniel Bonn·Jacques Meunier
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Abstract

We investigate the nonlinear rheological behavior of colloidal suspensions of Laponite, a synthetic clay, driven by a steady and homogeneous shear strain. We show that the external drive leads to a drastic slowing down of the aging dynamics or even, in some cases, in the rejuvenation of the system. Under shear, after a surprisingly long time, the spontaneous aging process observed at rest is suppressed. The system then reaches a non-equilibrium stationary state, characterised by a complex viscosity depending on the applied shear rate. In addition, the glass exhibits a non-Newtonian shear-thinning behavior. These rheological behaviors confirm recent numerical and theoretical predictions.

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Bérengère Abou, Daniel Bonn, Jacques Meunier. 2003-03-24. Nonlinear rheology of Laponite suspensions under an external drive. https://doi.org/10.1122/1.1574022

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