Rupture of thin nematic walls between isotropic droplets of the same mesogenic material

Abstract

ABSTRACT We prepared isotropic droplets surrounded by nematic fringes in smectic A freely suspended films. During their coalescence, a thin nematic film is formed that acts as a barrier and separates the isotropic cores of these droplets. This film ruptures in the course of the droplet merging process. The observation of the film dynamics provides an exceptional opportunity to study the rupture of a thin liquid barrier embedded in a surrounding viscous liquid. A detailed dynamic characterisation of the nematic walls is performed. Qualitatively similar observations have been reported in 3D for oil drops coalescing in water and vice versa, where the rupture of an intermediate thin fluid film retards the merging process. The peculiarity of the system reported here is that the material of the droplets and the membrane is identical.