EFFECTS OF LONDON-VANDERWAALS FORCES ON THE THINNING AND RUPTURE OF A DIMPLED LIQUID-FILM AS A SMALL DROP OR BUBBLE APPROACHES A FLUID-FLUID INTERFACE

When a small drop or bubble approaches a fluid-fluid interface, a thin liquid film forms between them and begins to drain. As the thickness of the draining film become sufficiently small left bracket about 1,000 A (100 nm) right bracket , the effects of the London-van der Waals forces and of the repulsive force of any electrostatic double layer become important. C. Y. Lin and J. C. Slattery developed a hydrodynamic theory for the first portion of the coalescence process: the drainage of the thin liquid film while it is sufficiently thick that the effects of London-van der Waals forces and of electrostatic forces can be ignored. The effect of the London-van der Waals forces are included.