水中分散させたw/oエマルションの安定性と界面活性剤の配向性

抄録

Making interfafial film strong is well known as one of the best methods of stabilizing emulsion, however, not any one of good method to estimate the degree of the strength of the interfacial film quantitively has been reported so far. The purpose of the present work is to propose the simple estimation method of interfacial film strength. The emulsion is added into solvent which cannot mix with it, stirred, and evaluated its breakdown ratio. We dispersed w/o emulsion in water and measured the breakdown ratio change with time of its w/o droplet. The breakdown ratio was well correlated with the obse vation with done b polarized microsccpy and electron microscopy of lipophilic surfactants saturated with water.
Water in oil emulsion of low breakdown ratio can be prepared with surfactants which got optical anisotropy when water was saturated. From ESR measurment we also knew that the more rigid the interfacial film, the more stable the w/o droplet. When we compared the change of breakdown ratio with storage stability, longer mixing time was needed to have good agreement. From these results, we conclude that the quantitative estimation of flexibility of an interfacial film and of orientatation of surfactants at the interface could be made successfully according to present method.