Thin liquid films: Where hydrodynamics, capillarity, surface stresses and intermolecular forces meet

Thin liquid films arise in many technological applications and biological phenomena. They also present a fascinating object of study, because of a rich interplay between capillarity, hy-drodynamics, interfacial transport phenomena and interfacial rheology, as well as the effects of interaction forces when films thin down to molecular thicknesses. Recent advances in experimental techniques have given further insights in the variety of physical phenomena, which can occur. These tech-niques are briefly reviewed. How these techniques can be utilised is illustrated by recent studies addressing the effect of interfacial rheological stresses on drainage, the interplay be-tween capillarity and hydrodynamics during film retraction, and the solutocapillary stabilisation of films. Finally, we briefly discuss the challenges of conducting drainage measurements at high and varied capillary numbers and how these could be overcome by the combined use of experiments and simulations.

Automated summary

Thin liquid films present a complex interplay of capillarity, hydrodynamics, interfacial transport phenomena, interfacial rheology, and interaction forces. Recent advances in experimental techniques provide further insights into these physical phenomena, showing the potential of utilizing these techniques for studying thin liquid films.