Interface Activity of the Aqueous Solutions of Anionic Gemini Surfactants

Anionic Gemini surfactant system were investigated in this paper. The results reveal that the (critical) micella concentration(CMC) of Gemini surfactant has a much lower value compared with that of (conventional) monomeric one and CMC is decreased upon increasing spacer length. Surface tensions of Gemini surfactants were studied by means of the drop volume method. The surface tension of Gemini surfactant with c_(20) is two orders of magnitude lower than that of monomeric surfactant, indicating that Gemini surfactant is more efficient in declining the surface tension of water. The interfacial tensions of crude oil and water systems were measured by virtue of the pendant drop method. The surface tension of the crude oil and water system is ultra-low when the system contains 0.1% Gemini D which indicates that Gemini surfactants show a great effect on declining the interfacial tensions between oil and water.