LAUSR

Abstract As a kind of typical functional substance, the wide application of surfactants causes growing concern about potential environmental safety hazard while benefiting mankind a lot, exploring approaches to achieve low cost, low risk and high performance is of great significance. In this paper, microcapsules encapsulating surfactant were prepared through solvent evaporation method, using hydrophobic ethyl cellulose as the shell material, which endowed the microcapsules environmental-friendliness and oil-phase targeting effect. Nonionic surfactant Span 20 was used as core material as an example. The mechanisms for the generation of the microcapsules and the effects of several factors, such as the stirring speed, core/shell weight ratio and molecular weight of ethyl cellulose, on the properties of the microcapsules were investigated, by which how to adjust the size and the mechanical properties of the microcapsules were determined. The oil-phase targeting performance of the microcapsules was verified, it was confirmed that the microcapsules could break rapidly when they encounter with oil phase interface, releasing surfactant to reduce the oil-water interfacial tension, while the microcapsules keep stable in water medium. Thereby in the practical applications of surfactants, the temperature resistance and salt resistance performance could be enhanced, and the interfacial efficiency could be achieved at low surfactant dosage. This work reveals a newly approach to employ surfactants smartly and more efficiently, and might have great potential in many fields.