Relationship of solubility parameters to interfacial properties of sucrose esters

A two-dimensional model of solubility parameters was established by simplifying the Hansenʹs three-dimensional model. In the model, there are three concentric quadrants and corresponding three regions—water region (W), first xylene region and second xylene region (X1 and X2). W, X1 and X2 indicate regions in which sucrose esters are soluble in water, insoluble in water or liquid paraffin but soluble in xylene, and completely soluble in xylene, respectively. Interfacial phenomena of different sucrose monoesters, diesters, triesters and some commercial sucrose esters at oil–water interface can be interpreted logically by means of the model. Interfacial properties of synthesized sucrose laurates, palmitates and stearates have been investigated. Their changes in interfacial tensions and CMC values with the changes in proportion of monoesters in sucrose esters conform to the principle obtained from the model.