Oil Bridges in Plateau Borders and Stability of Pseudoemulsion Films

3 Oil Bridges in Plateau Borders and Stability of Pseudoemulsion Films 

FIGURE 4.22 Image of two-dimensional foam prepared from saline solution of 4 wt.% of eommercial ethoxylated alcohol surfactant containing emulsified octane where oil drops have drained out of foam films into Plateau borders. (Reprinted from J. Colloid Interface Sci., 150, Koczo, K., Lobo, L., Wasan, D., 492. Copyright 1992, with permission from Elsevier.) 

Plateau border with trapped drops of polydimethylsiloxane oil 

FIGURE 4.23 Image of foam prepared from 0.1 M solution of commercial sample of sodium dodecyl-polyoxyethylene-3-sulfate (contaminated with NaCl and Na2S04) containing 0.1 wt.% emulsified PDMS oil of drop size 4-150 microns. Drops of oil trapped in Plateau borders are clearly visible. (Reprinted with permission from Basheva, E.S. et al. Langmuir, 16, 1000. Copyright 2000 American Chemical Society.) 

Use of the so-called film-trapping technique (FTT, see Chapter 2) by Denkov and coworkers [7, 58, 59, 102] permits direct measurement of the applied critical capillary pressure p necessary for rupture of the relevant pseudoemulsion films. This 

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