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arXiv · 1806.08623

Phase separation around heated colloid in bulk and under confinement

Sutapa Roy·Anna Maciolek
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Abstract

We study the non-equilibrium coarsening dynamics of a binary liquid solvent around a colloidal particle in a presence of a time-dependent temperature gradient that emerges after temperature quench of a suitably coated colloid surface. The solvent is maintained at its critical concentration and the colloid is fixed in space. The coarsening patterns near the surface are shown to be strongly dependent on the colloid surface adsorption properties and on the temperature evolution. The temperature gradient alters the morphology of a binary solvent near the surface of a colloid as compared to the coarsening proceeding at constant temperature everywhere. We also present results for the evolution of coarsening in thin films with confining surfaces preferring one species of the binary liquid mixture over the other. Confinement leads to a faster phase segregation process and formation of a bridge connecting the colloid and both the confining walls.

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Sutapa Roy, Anna Maciolek. 2018-06-22. Phase separation around heated colloid in bulk and under confinement. https://doi.org/10.1039/c8sm01258j

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