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A Model for the Elasticity of Compressed Emulsions

Martin-Daniel Lacasse·Gary S. Grest·Dov Levine·T. G. Mason·D. A. Weitz
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Abstract

We present a new model to describe the unusual elastic properties of compressed emulsions. The response of a single droplet under compression is investigated numerically for different Wigner-Seitz cells. The response is softer than harmonic, and depends on the coordination number of the droplet. Using these results, we propose a new effective inter-droplet potential which is used to determine the elastic response of a monodisperse collection of disordered droplets as a function of volume fraction. Our results are in excellent agreement with recent experiments. This suggests that anharmonicity, together with disorder, are responsible for the quasi-linear increase of $G$ and $Π$ observed at $φ_c$.

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Martin-Daniel Lacasse, Gary S. Grest, Dov Levine, T. G. Mason, D. A. Weitz. 1996-03-12. A Model for the Elasticity of Compressed Emulsions. https://doi.org/10.1103/physrevlett.76.3448

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