Phase Behavior of Microemulsions Made with n-Alkyl Monoglucosides and n-Alkyl Polyglycol Ethers

Abstract

The phase behavior of mixtures of water, octane, n-alkyl polyglycol ethers (C i E j ), and n-alkyl β-d-glucopyranosides (C m G1) is systematically studied as a function of temperature and composition. The addition of C m G1 to water−octane−C i E j mixtures promotes formation of a three-phase region that is nearly independent of temperature in all mixtures studied. The size and extent of this three-phase region are shown as a function of C m G1 concentration and hydrophobicity and C i E j amphiphilicity. This unique behavior arises from the extremely low oil solubility of the alkyl monoglucosides.

Characterization of Microemulsion Systems Formed by a Mixed 1,3‐Dioxolane Ethoxylate/Octyl Glucoside Surfactant System

“…In general, alkyl glucosides as lone surfactants are not effective amphiphiles for microemulsion formation, mainly because of their low solubility in oils [9][10][11]. However, C 8 bG 1 readily forms microemulsions in the presence of alkylethyleneglycol ether-based oils [12][13][14] and cosurfactants such as medium-chain alcohols [15][16][17][18], alkyl sulfates [14,19], or C i E j [12,14]. Also, unlike ionic surfactant-based and alkyl ethoxylate-based microemulsions, for which phase behavior can be modified by addition of salt or by changing the temperature, respectively, alkyl glucoside-based microemulsion phase behavior is insensitive to environmental triggers [9][10][11].…”

Four Different C8G1Alkylglucosides. Anomeric Effects and the Influence of Straight vs Branched Hydrocarbon Chains

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phase behavior (6)(7)(8)(9)(10)(11)(12)(13)(14), microemulsions (15)(16)(17), and genIn this work some of the physical-chemical properties of four eral reviews (18, 19). Earlier still, we find articles about the different alkylglucosides are presented.

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The Effect of Anomeric Head Groups, Surfactant Hydrophilicity, and Electrolytes onn-Alkyl Monoglucoside Microemulsions

“…10 in Ref. (16)), the entire three-phase region tilts to higher temperature with decreasing surfactant concentration. Furthermore, the three-phase region eventually closes at higher temperature (ϳ66°C) reflecting the smooth partitioning of C 12 E 8 into octane and passing of the upper critical tie-line.…”

“…The hydrophilic nature of the glucose head group makes these surfactants extremely insoluble in many oils, including alkanes (15,16). So although these compounds exhibit upper miscibility gaps in the binary water-surfactant mixture (4,15,20) that are similar to the family ethoxylated alcohol surfactants (C i E j 's), the ternary phase behavior of water-alkane-C m G n mixtures is drastically different than that of water-alkane-C i E j mixtures.…”