70th Annual Meeting of the APS Division of Fluid Dynamics (November 19, 2017 — November 21, 2017)

P0043: One droplet, two regimes: unexpected dynamics on silicone elastomers

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Authors

• Aurelie Hourlier-Fargette, Institut Jean Le Rond d'Alembert, UPMC, Paris
• Arnaud Antkowiak, Institut Jean Le Rond d'Alembert, UPMC, Paris
• Sebastien Neukirch, Institut Jean Le Rond d'Alembert, UPMC, Paris

DOI: https://doi.org/10.1103/APS.DFD.2017.GFM.P0043

Aqueous droplets sliding down homogeneous plates of silicone elastomers exhibit an unexpected behavior: two successive regimes with two different constant speeds are identified, with a sharp transition between them. This dynamics is surprising, as there is no modification of the substrate below the droplet. By analyzing both the motion of the liquid inside the droplet and the evolution of its interfacial properties, we show that the unexpected dynamics is due to the migration of uncrosslinked silicone oligomers from the elastomer to the water-air interface.