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arXiv · 1309.1755

From adhesion to wetting of a soft particle

Thomas Salez·Michael Benzaquen·Elie Raphaël
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Abstract

Using a thermodynamical approach, we calculate the deformation of a spherical elastic particle placed on a rigid substrate, under zero external load, and including an ingredient of importance in soft matter: the interfacial tension of the cap. In a first part, we limit the study to small deformation. In contrast with previous works, we obtain an expression for the energy that precisely contains the JKR and Young-Dupré asymptotic regimes, and which establishes a continuous bridge between them. In a second part, we consider the large deformation case, which is relevant for future comparison with numerical simulations and experiments on very soft materials. Using a fruitful analogy with fracture mechanics, we derive the exact energy of the problem and thus obtain the equilibrium state for any given choice of physical parameters.

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cond-mat.softcond-mat.mes-hallcond-mat.mtrl-sciphysics.chem-phphysics.class-ph

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Thomas Salez, Michael Benzaquen, Elie Raphaël. 2013-09-06. From adhesion to wetting of a soft particle. https://doi.org/10.1039/c3sm51780b

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