Soap film bursting

All this seems to be simple, but the strange thing is that the work done by the capillary forces is  

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Further Developments Break-up of Suspended, Supported and Intercalated Films. There is a whole family of closely related problems, ranging from (i) the bursting of soap films suspended in the air (see Fig. 1.29), studied by Mysels, K. through the intermediate case of (ii) films supported on a liquid or solid and exposed to the air to that of (iii) films intercalated between a solid and a soft material (rubber). 

This law is similar to the one derived by F. Culick, which describes the bursting of soap films, after substituting 27 for S (see section 8.4.4). ... 

Bursting of a soap film in a viscous environment" (with J.F. Joanny), Phvsica 147A. 238-255 (1987). 

II was Isaac Newton who, following Hooke s observation of holes3 itt a soap bubble just before it bursts, described so-called black3 films of various shades. 

But Leidenfrost does not extend this contractile force to a general property of liquid surfaces he attributes it to the lubricating part of the soap, which, according to him, separates from the other elements of the solution, and constitutes a thin film on the outside of the bubble moreover, still according to him, the aqueous part of the film has a force of opposed nature, being an explosive force it is the latter which makes burst the bubble. 

The author advances that a soap water film developed in a solid ring can be pierced by a liquid je without breakingt, if the tension of the liquid of this jet is equal or higher than that of the liquid of the film it happens, for example, with water jets through soap, pure water, oil, carbon bisulphide, and even mercury but if the difference of the tensions is in the opposite direction, as with ether or alcohol jets, the film bursts immediately. It is even enough, so that it disappears, to simply touch it with a point wetted with one of these two liquids. 

If all liquids can develop into thin films, they present nevertheless, for the ease of this development and the persistence of the generated films, considerable differences one inflates easily, for example, large bubbles at the opening of a pipe with soap water, but nobody would think to try it with pure water the transverse films in a bottle persist an enormous time if the liquid employed is glyceric liquid, and they burst almost immediately if it is water ( 229). 

This deduction seems, at first sight, to agree badly with observation indeed, one usually sees films decreasing much in thickness before bursting when a soap bubble is inflated, it often reaches a large size, and bursts consequently only when the film becomes very thin if one deposits on the surface of soap water a bubble of this liquid, a bubble which is transformed at once into a segment of a sphere, the color of its top can go, one knows, to intense black, which corresponds to a thickness of approximately 0.00001mm, etc. 

One sees, according to this discussion, that, in the films of the third category, the moment of rupture is hastened by evaporation also our caps of household soap solution ( 248) which, in an atmosphere saturated with water vapor, persisted several hours, lasted only four to five minutes when they were produced in the closed bottle, but without saturation of its atmosphere if one had formed them in the entirely open air, no doubt they would have burst earlier still. 

A soap bubble consists of an air pocket enclosed in a thin film of soap in water. As the water evaporates, the film breaks and the bubble bursts. Glycerol added to the soap-water mixture forms hydrogen bonds to both the soap and water molecules. This slows the rate of evaporation of the water and increases the strength of the film, allowing the production of very large bubbles. 

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