2016 Volume 89 Issue 10 Pages 333-339
Water-in-oil (W/O) emulsions composed of hydrocarbon oil (octane, dodecane and hexadecane) as a continuous phase were colloidally stabilized with the addition of vegetable oil (soybean oil) to the hydrocarbon oil even in the absence of any emulsifiers such as surfactants and amphiphilic polymers. For example, the turbidity of the emulsifier-free (EF-) W/Octane emulsions did not remain at 2 h after preparation while the turbidity of EF-W/Octane emulsions containing soybean oil with weight fraction of 0.2 in oil blend (octane and soybean oil) remained even at 12 h after preparation. Namely, the colloidal stability of EF-W/Octane emulsions was increased with the addition of soybean oil to octane. The colloidal stability of EF-W/Octane emulsions was enhanced with increase in the content of soybean oil in octane. Furthermore, we found that the colloidal stability of EF-W/Octane emulsions was increased with the addition of higher fatty acid (linoleic acid, oleic acid, stearic acid and palmitic acid) to octane.
