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PubMed · 15323838

Topography driven spreading.

G McHale·N J Shirtcliffe·S Aqil·C C Perry·M I Newton
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Abstract

Roughening a hydrophobic surface enhances its nonwetting properties into superhydrophobicity. For liquids other than water, roughness can induce a complete rollup of a droplet. However, topographic effects can also enhance partial wetting by a given liquid into complete wetting to create superwetting. In this work, a model system of spreading droplets of a nonvolatile liquid on surfaces having lithographically produced pillars is used to show that superwetting also modifies the dynamics of spreading. The edge speed-dynamic contact angle relation is shown to obey a simple power law, and such power laws are shown to apply to naturally occurring surfaces.

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Hydrophobic and Hydrophilic InteractionsModels, ChemicalSurface PropertiesWettabilityJournal ArticleResearch Support, Non-U.S. Gov't

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G McHale, N J Shirtcliffe, S Aqil, C C Perry, M I Newton. 2004-07-15. Topography driven spreading.. https://doi.org/10.1103/physrevlett.93.036102

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