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arXiv · 2111.06019

Flow-Switched Bistability in a Colloidal Gel with Non-Brownian Grains

Yujie Jiang·Soichiro Makino·John R. Royer·Wilson C. K. Poon
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Abstract

We show that mixing a colloidal gel with larger, non-Brownian grains generates novel flow-switched bistability. Using a combination of confocal microscopy and rheology, we find that prolonged moderate shear results in liquefaction by collapsing the gel into disjoint globules, whereas fast shear gives rise to a yield-stress gel with granular inclusions upon flow cessation. We map out the state diagram of this new `mechanorheological material' with varying granular content and demonstrate that its behavior is also found in separate mixture using different particles and solvents.

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Yujie Jiang, Soichiro Makino, John R. Royer, Wilson C. K. Poon. 2021-11-11. Flow-Switched Bistability in a Colloidal Gel with Non-Brownian Grains. https://doi.org/10.1103/physrevlett.128.248002

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