Droplet behavior on flat and textured surfaces: Co-occurrence of Deegan outward flow with Marangoni solute instability

It is demonstrated experimentally that the solution droplet behavior is governed by the co-occurrence of outward hydrodynamic and surface tension (solute Marangoni) induced flows. Potassium ferrocyanide allows the effective visualization of the processes taking place in the droplet. Wetting properties of the substrate govern the shape evolution of the evaporated droplet. Quantitative estimation of the wetting properties of textured polymer surface is presented.

Crown-like potassium ferrocyanide deposit formed on the polymer honeycomb relief (optical microscopy image).Figure optionsDownload as PowerPoint slide