Delayed coalescence of surfactant containing sessile droplets

  title={Delayed coalescence of surfactant containing sessile droplets},
  author={Myrthe A Bruning and Maxime Costalonga and Stefan Karpitschka and Jacco H. Snoeijer},
  journal={Physical Review Fluids},
When two sessile drops of the same liquid touch, they merge into one drop, driven by capillarity. However, the coalescence can be delayed, or even completely stalled for a substantial period of time, when the two drops have different surface tensions, despite being perfectly miscible. A temporary state of non-coalescence arises, during which the drops move on their substrate, only connected by a thin neck between them. Existing literature covers pure liquids and mixtures with low surface… 

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