Permeability of common black foam films to gas. Part 1

✍ Scribed by Rumen Krustev; Dimo Platikanov; Michael Nedyalkov

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 586 KB
• Volume: 79
• Category: Article
• ISSN: 0927-7757
• DOI: 10.1016/0927-7757(93)80167-d

✦ Synopsis

An experimental

method for measuring the permeability coefficient K for the permeation of air through black foam films is described. A series of measurements of K for sodium dodecyl sulfate plus sodium chloride aqueous solutions have been performed.

Experimental results concerning the dependences of K on surfactant concentration C, NaCl concentration C,, and temperature T are reported.

A stepwise decrease in permeability K at the transition from common black film (CBF) to Newton black film (NBF) has been found, the K values of the thinnest NBF being 2-3 times lower than those of the essentially thicker CBF. The results show that gas permeation through black foam films is mainly determined by the properties of the surfactant layers: monolayers in the case of CBFs and a bilayer in the case of NBFs. The experimental results concerning the permeability of CBFs are discussed on the basis of theories of gas permeation through monomolecular layers.