Thin adhesive oil films lead to anomalously stable mixtures of water in oil

Claire Nannette (1) , Jean Baudry (1) , Anqi Chen (2) , Yiqiao Song (2) , Abdulwahed Shglabow (1) , Nicolas Bremond (1) , Damien Démoulin , Jamie Walters , David Weitz (2) , Jérôme Bibette (1)

1 LCMD - Laboratoire Colloïdes et Matériaux Divisés
2 SEAS - Harvard John A. Paulson School of Engineering and Applied Sciences

Oil and water can only be mixed by dispersing droplets of one fluid in the other. When two droplets approach one another, the thin film that separates them invariably becomes unstable, causing the droplets to coalesce. The only known way to avoid this instability is through addition of a third component, typically a surfactant, which stabilizes the thin film at its equilibrium thickness. We report the observation that a thin fluid film of oil separating two water droplets can lead to an adhesive interaction between the droplets. Moreover, this interaction prevents their coalescence over timescales of several weeks, without the use of any surfactant or solvent.

Domaines: Chimie théorique et/ou physique; Polymères

Claire Nannette, Jean Baudry, Anqi Chen, Yiqiao Song, Abdulwahed Shglabow, et al.. Thin adhesive oil films lead to anomalously stable mixtures of water in oil. Science, 2024, 384 (6692), pp.209-213. ⟨10.1126/science.adj6728⟩. ⟨hal-04552218⟩