Abstract
The LC phase behavior of ternary mixtures of the two corresponding branched non-ionic surfactants 1,3-bis-(methoxy-tetraoxyethylene)-2-propoxy-tetradecane (Y-surfactant) and 1,3-bis-(heptyloxy)-2-propoxyoctaoxyethylene mono-methyl ether (V-surfactant) and water were studied by polarizing microscopy. The two branched surfactants, which have different molecular geometries but nearly the same hydrophilic-lipophilic volume ratio, exhibit extremely different phase behavior in binary surfactant/water systems. For the ternary mixtures of Y- and V-surfactant and water we found-according to established packing models-a continuous stabilization of the cubic and hexagonal phases and a destabilization of the lamellar phase with increasing amount of Y-surfactant. On the other hand, we observed a thermal stabilization of the lamellar phase. The maximal transition temperatures of the lamellar phase pass a maximum with increasing amount of Y-surfactant.
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References
Israclachvili JN, Mitchell DJ, Ninham BW (1976) J Chem Soc Faraday Trans 2, 72:1525
Marques E, Khan A, da Graca Miguel M, Lindman B (1993) J Phys Chem 97:4729
Kratzat K, Finkelmann H (1993) Liquid Crystals 13(5):691
Kratzat K, Finkelmann H (1994) Colloid Polym Sci 272(4):400
Jahns E, Finkelmann H (1987) Colloid Polym Sci 265(4):304
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Kratzat, K., Stubenrauch, C. & Finkelmann, H. Mixtures of branched non-ionic oligo-oxyethylene surfactants in aqueous solutions — the effect of molecular geometry on LC phase behaviour 4. Colloid Polym Sci 273, 257–262 (1995). https://doi.org/10.1007/BF00657832
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DOI: https://doi.org/10.1007/BF00657832