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DOE OSTI · 2404546

Kinetics of Shear-Induced Structural Ordering in Dense Colloids

He, HongRui·Lee, Jonghun·Jiang, Zhang·He, Qiming·Dinic, Jelena·Chen, Wei·Narayanan, Suresh·Lin, Xiao-Min
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Abstract

The macroscopic rheological response of a colloidal solution is highly correlated with the local microscopic structure, as revealed by an in situ Rheo-SAXS experiment with a high temporal resolution. Oscillatory shear can induce a strain-controlled ordering-to-disorder transition, resulting in a shear-thickening process that is different from the normal shear-thickening behavior that is driven by hydrodynamics and particle friction. Here, we reveal that there is a complex time-dependent kinetics toward structural ordering under different applied strains. When the strain amplitude reaches a critical value that starts to induce disordering in the system, the pathway toward the dynamic equilibrium can also become highly non-monotonic. Within the same oscillatory cycle, there is a strong correlation of ordering with different phases of the oscillation, with the system oscillating between two dynamic metastable states.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYChemical structureCrystalsKineticsOrder-to-disorder transitionOscillationOscillatory shearRheo-SAXSScattering

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He, HongRui, Lee, Jonghun, Jiang, Zhang, He, Qiming, Dinic, Jelena, Chen, Wei, Narayanan, Suresh, Lin, Xiao-Min. 2023-08-10. Kinetics of Shear-Induced Structural Ordering in Dense Colloids. https://doi.org/10.1021/acs.jpcb.3c03290

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