Ionic liquids surfactants

Shen, Y. F, Zhang, Y. ]., Kuehner, D., Yang, G. F, Yuan, F. Y., and Niu, L. (2008]. ion-responsive behavior of ionic-liquid surfactant aggregates with applications in controlled release and emulsification. Chem. Phys. Chem., 9, pp. 2198-2202. 

Ionic Liquids Surfactant Agents for Layered Silicates... 

Observed changes in the physicochemical and micellar properties of the pyrro-lidinium imidazoUum or alkylammonium alkylcarboxylates protic ionic liquid surfactants in mixtures with water can be linked to the nature of the cation. Figure 7.14 shows, for example, lamellar patterns bilayer systan of diisopropylammonium octanoate in water (50 % w/w). By comparison with classical anionic surfactants having inorganic counterions (LP, Na. ..), these monomers exhibit a higher ability to aggregate in aqueous solution, demonstrating their potential applicability as a surfactant. 

Microemulsions with an ionic liquid surfactant and room temperature ionic liquids as polar p>seudo-phase. Journal of Physical Chemistry B, 113(2), 465-473. 

Gao, Y. Zhao, X. Dong, B. Zheng, L. Li, N. Zhang, S. (2006c). Inclusion complexes of P-cyclodextrin with ionic liquid surfactants. /. Phys. Chem. B, 110, 8576-8581. 

It should be emphasized that ionic liquids are simply organic salts that happen to have the characteristic of a low melting point. Many ionic liquids have been widely investigated with regard to applications other than as liquid materials as electrolytes, phase-transfer reagents [12], surfactants [13], and fungicides and biocides [14, 15], for example. 

The production of linear alkyl benzenes (LABs) is carried out on a large scale for the production of surfactants. The reaction involves the reaction between benzene and a long-chain alkene such as dodec-l-ene and often gives a mixture of isomers. Greco et al. have used a chloroaluminate(III) ionic liquid as a catalyst in the preparation of LABs [83] (Scheme 5.1-53). 

Liquid breakup High resistivity liquids ( > 1010 ohm cm) Ionic liquids ( o < 1010 ohm cm) Statistical distribution due to ion concentration fluctuations (most probable charge = 0) Double layer disruption Unequal ion mobility or migration rates Interface contaminants (incl. surfactants)... 

In addition to their use as solvents, surfactants, and biocides, ionic liquids are attractive for use in catalytic reactions due to their ability to activate reactant molecules, the ease of separation from final products, thermal stability, solubility of gaseous reactants, among other properties. Amit Gujar and Mark White (Mississippi State Univ., USA) show, for example,... 

Anderson, J.L. et al.. Surfactant solvation effects and micelle formation in ionic liquids, Chem. Comm., 2444, 2003. 

Fletcher, K. A., and Pandey, S., Surfactant aggregation within room-temperature ionic liquid l-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, Langmuir, 20, 33-36, 2004. 

Merrigan, T.L., Bates, E.D., Dorman, S.C., and Davis, J.H., New fluorous ionic liquids function as surfactants in conventional room-temperature ionic liquids,... 

Mwongela, S. M., Numan, A., Gill, N. L., Agbaria, R. A., and Warner, I. M., Separation of achiral and chiral analytes using polymeric surfactants with ionic liquids as modifiers in micellar eletrokinetic chromatography. Anal. Chem., 75, 6089-6096,2003. 

Schnee, V. R, Baker, G. A., Rank, E., and Ralmer, C. R, Electrokinetic chromatographic characterization of novel pseudo-phases based on N-alkyl-N-methyl-pyrrolidinium ionic liquid type surfactants. Electrophoresis, 2J, 4141-4148,2006. 

The Diels-Alder reaction is an important and widely used reaction in organic synthesis (Sauer and Sustmann, 1980), and in the chemical industry (Griffiths and Previdoli, 1993). Rate enhancement of this reaction has been achieved by the use of solvents such as water, surfactants, very high pressure, lithium amides, alkylammonium nitrate salts, and macrocyclic hosts (Sherman et ak, 1998). Diels-Alder reactions can be ran in neutral ionic liquids (such as 1-butyl-3-methylimidazolium trifluoromethanesulfo-nate, l-butyl-3-methylimidazolium hexafluorophophate, l-butyl-3-methylimidazolium tetrafluoroborate, and l-butyl-3-methylimidazolium lactate). Rate enhancements and selectivities are similar to those of reactions performed in lithium perchlorate-diethyl ether mixtures. 

Fatty acids of sugars are potentially useful and fully green nonionic surfactants, but the lipase-mediated esterification of carbohydrates is hampered by the low solubility of carbohydrates in reaction media that support lipase catalysis in general. Because the monoacylated product (Figure 10.8) is more soluble in traditional solvents than is the starting compound, the former tends to undergo further acylation into a diester. In contrast, the CaLB-catalyzed esterification of glucose with vinyl acetate in the ionic liquid [EMIm][BF4] was completely selective. The reaction became much faster and somewhat less selective when conducted in... 

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