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arXiv · 0705.4210

Spontaneous Breakdown of Superhydrophobicity

Mauro Sbragaglia·Alisia M. Peters·Christophe Pirat·Bram M. Borkent·Rob G. H. Lammertink·Matthias Wessling·Detlef Lohse
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Abstract

In some cases water droplets can completely wet micro-structured superhydrophobic surfaces. The {\it dynamics} of this rapid process is analyzed by ultra-high-speed imaging. Depending on the scales of the micro-structure, the wetting fronts propagate smoothly and circularly or -- more interestingly -- in a {\it stepwise} manner, leading to a growing {\it square-shaped} wetted area: entering a new row perpendicular to the direction of front propagation takes milliseconds, whereas once this has happened, the row itself fills in microseconds ({\it ``zipping''})

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Mauro Sbragaglia, Alisia M. Peters, Christophe Pirat, Bram M. Borkent, Rob G. H. Lammertink, Matthias Wessling, Detlef Lohse. 2007-08-31. Spontaneous Breakdown of Superhydrophobicity. https://doi.org/10.1103/physrevlett.99.156001

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