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Capillary interactions between anisotropic colloidal particles.

J C Loudet·A M Alsayed·J Zhang·A G Yodh
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Abstract

We report on the behavior of micron-sized prolate ellipsoids trapped at an oil-water interface. The particles experience strong, anisotropic, and long-ranged attractive capillary interactions which greatly exceed the thermal energy k(B)T. Depending on surface chemistry, the particles aggregate into open structures or chains. Using video microscopy, we extract the pair interaction potential between ellipsoids and show it exhibits a power law behavior over the length scales probed. Our observations can be explained using recent calculations, if we describe the interfacial ellipsoids as capillary quadrupoles.

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AnisotropyCapillary ActionColloidsComputer SimulationDiffusionMicrofluidicsMicrospheresModels, ChemicalOilsParticle SizeSiliconSurface PropertiesWaterJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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J C Loudet, A M Alsayed, J Zhang, A G Yodh. 2005-01-03. Capillary interactions between anisotropic colloidal particles.. https://doi.org/10.1103/physrevlett.94.018301

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