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arXiv · 1602.01106

Dynamic stratification in drying films of colloidal mixtures

Andrea Fortini·Ignacio Martín-Fabiani·Jennifer Lesage De La Haye·Pierre-Yves Dugas·Muriel Lansalot·Franck D'Agosto·Elodie Bourgeat-Lami·Joseph L. Keddie·Richard P. Sear
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Abstract

In simulations and experiments, we study the drying of films containing mixtures of large and small colloidal particles in water. During drying, the mixture stratifies into a layer of the larger particles at the bottom with a layer of the smaller particles on top. We developed a model to show that a gradient in osmotic pressure, which develops dynamically during drying, is responsible for the segregation mechanism behind stratification.

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Andrea Fortini, Ignacio Martín-Fabiani, Jennifer Lesage De La Haye, Pierre-Yves Dugas, Muriel Lansalot, Franck D'Agosto, Elodie Bourgeat-Lami, Joseph L. Keddie, Richard P. Sear. 2016-03-06. Dynamic stratification in drying films of colloidal mixtures. https://doi.org/10.1103/physrevlett.116.118301

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