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arXiv · 1602.07937

Controlled uniform coating from the interplay of Marangoni flows and surface-adsorbed macromolecules

Hyoungsoo Kim·François Boulogne·Eujin Um·Ian Jacobi·Ernie Button·Howard A. Stone
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Abstract

Surface coatings and patterning technologies are essential for various physicochemical applications. In this Letter, we describe key parameters to achieve uniform particle coatings from binary solutions: First, multiple sequential Marangoni flows, set by solute and surfactant simultaneously, prevent non-uniform particle distributions and continuously mix suspended materials during droplet evaporation. Second, we show the importance of particle-surface interactions that can be established by surface-adsorbed macromolecules. To achieve a uniform deposit in a binary mixture, a small concentration of surfactant and surface-adsorbed polymer (0.05 wt% each) is sufficient, which offers a new physicochemical avenue for control of coatings.

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Hyoungsoo Kim, François Boulogne, Eujin Um, Ian Jacobi, Ernie Button, Howard A. Stone. 2016-03-22. Controlled uniform coating from the interplay of Marangoni flows and surface-adsorbed macromolecules. https://doi.org/10.1103/physrevlett.116.124501

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