title: A one-step process for oil-in-water-in-oil double emulsion formation using a single surfactant.
abstract: A one-step double emulsification protocol using one surfactant was developed for oil-in-water-in-oil (O(1)/W/O(2)) double emulsions. Two n-alkane oils and three different surfactants were studied, with focus placed on a formulation containing mineral oil, glycerol monoleate (GMO) and deionized water. Phenomenologically, double emulsion formation and stability originate from the combined actions of phase inversion and interfacial charging of the oil/water interface during high shear homogenization. Based on the extent of double emulsion formation and stability, a critical emulsification zone dependent on the weight ratios of GMO to water was identified. Within this critical zone, enhanced O(1)/W/O(2) emulsion formation occurred at higher pH and lower salt concentrations, demonstrating the key role of interfacial charging on double emulsification. Overall, this novel approach provides a novel platform for the development of double emulsions with simple compositions and processing requirements.
authors.affiliation: Department of Chemistry and Biology, Ryerson University, Toronto, ON, Canada.
authors.forename: Mamata
authors.initials: M
authors.lastname: Pradhan
authors.forename: Dérick
authors.initials: D
authors.lastname: Rousseau