Gemini surfactants phase behavior

Gemini Surfactants Synthesis, Interfacial and Solution-Phase Behavior, and Applications, edited by Raoul Zana and Jiding Xia... 

Zana et al. have investigated various properties of a series of gemini surfactants including their thermotropic and lyotropic phase behavior. They report that the 12-4-12 and 12-8-12 compounds form hexagonal... 

Kunieda, H., Masuda, N., and Tsubone, K. (2000) Comparison between phase behavior of anionic dimeric (Gemini-type) and monomeric surfactants in water and water-oil. Langmuir, 16, 6438-6444. 

SAR Sardar, N., Ah, M.S., Kamil, M., and Kabir-ud-Din, Phase behavior of nonionic polymer hydroxypropylmethyl cellulose Effect of gemini and single-chain surfactants on the energetics at the cloud point, J. Chem. Eng. Data, 55,4990, 2010. 

Colloidal Biomolecules, Biomaterials, and Biomedical Applications, edited by Abdeihamid Eiaissari Gemini Surfactants Synthesis, Interfacial and Solution-Phase Behavior, and Applications, edited by Raoui Zana and Jiding Xia Colloidal Science of Flotation, Anh V. Nguyen and Hans Joachim Schuize... 

The next section discusses chemical structures, synthesis, and purification of gemini surfactants. Section III reviews the behavior of gemini surfactants in solutions below the CMC. Section IV deals with their behavior at interfaces. The fifth section reviews micelle formation and solubilization. Section VI deals with micelle properties. Microstructure of aqueous solution of gemini surfactants, rheology of these solutions, and mixed micellization are considered in the following three sections. Section X deals with the phase behavior of... 

Acharya, D.P., Kunieda, H., Shiba, Y., and Aratani, K. (2004) Phase and rheological behavior of novel Gemini-type surfactant systems. /. Phys. Chem. B., 108,1790-1797. 

First application of IL-based surfactants as pseudophases in MLC was reported in 2009 [42], It was a preliminary study regarding the retention behavior of benzene using three different LC stationary phases (Eehpse XDB C8,Zorbax C8,and Gemini C18) and Cj C Im-Br. A comparison was also made with the conventional cationie surfactant cetyltrimethylammonium bromide (CTAB) showing similar performanee. 

As in conventional surfactants, the C20 and CMC values decrease with an increase in te total number of carbon atoms in the molecule. However, unlike this behavior in conventional surfactants, when the number of carbons in the alkyl chain of the Geminis exceeds a certain value (about 14 carbon atoms per chain, the exact number dependent on the Gemini structure, temperature and the electrolyte content of the of the aqueous phase), the linear relationship with the log of the C20 value or with the log of the CMC breaks down. The log C20 or log CMC values start to deviate more and more from this linear relationship with the C20 and CMC values becoming larger than expected, that is in the direction of decreased surface activity and micellization tendency. 

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