The dynamic stability of w/o emulsions prepared from vegetable oil

✍ Scribed by F. Groeneweg; F. van Voorst Vader; W.G.M. Agterof

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 767 KB
• Volume: 48
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(93)80011-e

✦ Synopsis

The dynamic stability of 50% W/O emulsions prepared from vegetable oil was measured as a function of the concentration of the emulsifier monoBnoleylglycero1. Four concentration regimes were detected. Homogeneous emulsions could not be made at very low concentrations, while homogeneous emulsions with a relatively slow rate of coalescence were obtained at about 0.2% emulsifier. Coalescence became faster when the concentration was increased above ahout 0.5%. Finally the emulsion became stable above about 2% (the CMC). These results can be explained by a model for the coalescence rate that accounts for: the hydrodynamics of the rate of approach of the droplets, the van der Waals force, hindered film drainage because of the adsorbed emulsifier molecules and an additional attractive force which is possibly connected with the expulsion of the oil molecules out of the film.