The surface tells it all: relationship between volume and surface fraction of liquid dispersions. Issue 38 (9th September 2016)

• Record Type: Journal Article
• Authors: Forel, Emilie; Rio, Emmanuelle; Schneider, Maxime; Beguin, Sebastien; Weaire, Denis; Hutzler, Stefan; Drenckhan, Wiebke
• Is Part Of: Soft matter. Volume 12:Issue 38(2016)
• Page Start: 8025
• Page End: 8029
• Publication Date: 2016-09-09
• Subjects: Soft condensed matter -- Periodicals; 530.413
• DOI: 10.1039/c6sm01451h
• Languages: English
• ISSNs: 1744-683X

Abstract

Abstract : We show experimentally and theoretically how the volume fraction of a liquid dispersion can be obtained from the surface (or wetting) fraction of the dispersion on a wall. The latter can be computed using simple photography. Abstract : The properties of liquid dispersions, such as foams or emulsions, depend strongly on the volume fraction ϕ of the continuous phase. Concentrating on the example of foams, we show experimentally and theoretically that ϕ may be related to the fraction ϕ s of the surface at a wall which is wetted by the continuous phase – given an expression for the interfacial energy or osmotic pressure of the bulk system. Since the surface fraction ϕ s can be readily determined from optical measurement and since there are good general approximations available for interfacial energy and osmotic pressure we thus arrive at an advantageous method of estimating ϕ . The same relationship between ϕ and ϕ s is also expected to provide a good approximation of the fraction of the bubble or drop surface which is wetted by the continuous phase. This is a parameter of great importance for the rheology and ageing of liquid dispersions.