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arXiv · 2208.11177

Phase Separation in Wetting Ridges of Sliding Drops on Soft and Swollen Surfaces

Lukas Hauer·Zhuoyun Cai·Doris Vollmer·Jonathan T. Pham
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Abstract

Drops in contact with swollen, elastomeric substrates can induce a capillary-mediated phase separation in wetting ridges. Using laser scanning confocal microscopy, we visualize phase separation of oligomeric silicone oil from a crosslinked silicone network during steady-state sliding of water drops. We find an inverse relationship between the oil tip height and the drop sliding speed, which is rationalized by competing transport timescales of oil molecules: separation rate and drop-advection speed. Separation rates in highly swollen networks are as fast as diffusion in pure melts.

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Lukas Hauer, Zhuoyun Cai, Doris Vollmer, Jonathan T. Pham. 2022-08-23. Phase Separation in Wetting Ridges of Sliding Drops on Soft and Swollen Surfaces. https://doi.org/10.1103/physrevlett.130.058205

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