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arXiv · 1507.03451

Slip-Mediated Dewetting of Polymer Microdroplets

Joshua D. McGraw·Tak Shing Chan·Simon Maurer·Thomas Salez·Michael Benzaquen·Élie Raphaël·Martin Brinkmann·Karin Jacobs
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Abstract

Classical hydrodynamic models predict that infinite work is required to move a three-phase contact line, defined here as the line where a liquid/vapor interface intersects a solid surface. Assuming a slip boundary condition, in which the liquid slides against the solid, such an unphysical prediction is avoided. In this article, we present the results of experiments in which a contact line moves and where slip is a dominating and controllable factor. Spherical cap shaped polystyrene microdroplets, with non-equilibrium contact angle, are placed on solid self-assembled monolayer coatings from which they dewet. The relaxation is monitored using \textit{in situ} atomic force microscopy. We find that slip has a strong influence on the droplet evolutions, both on the transient non-spherical shapes and contact line dynamics. The observations are in agreement with scaling analysis and boundary element numerical integration of the governing Stokes equations, including a Navier slip boundary condition.

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Joshua D. McGraw, Tak Shing Chan, Simon Maurer, Thomas Salez, Michael Benzaquen, Élie Raphaël, Martin Brinkmann, Karin Jacobs. 2016-03-09. Slip-Mediated Dewetting of Polymer Microdroplets. https://doi.org/10.1073/pnas.1513565113

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