 Disjoining pressure

Disjoining pressure is the thickness-dependent normal stress caused by intermolecular interactions between nearby interfaces. An attractive law $\Pi (h)=V/h^3$ grows as a film thins and can drive rupture.

Disjoining pressure is a concept in physical chemistry and materials science that refers to the pressure difference across a thin film or interface due to molecular interactions and forces. It is particularly relevant in the study of thin liquid films, such as those found in emulsions, foams, or biological membranes. Disjoining pressure arises from three primary sources: 1. **Van der Waals Forces**: These are attractive forces that can cause thin films to collapse when the film thickness is reduced.