878550-42-6Relevant articles and documents
A comparative study on the interface behavior of different counter anion long chain imidazolium ionic liquids
Saien, Javad,Kharazi, Mona
, p. 136 - 141 (2016)
The adsorption behavior of amphiphilic long-chain imidazolium ionic liquids (ILs), n-alkyl-3-methylimidazolium halides, [Cnmim][X], n = 12, 14, 16 and X = Cl-, Br-, I-, at the interface of n-butyl acetate + water system was studied. The ILs bulk concentration range of 1.00·10- 5-1.00·10- 2 mol·dm- 3 and temperature of 293.2-318.2 K were applied. The interfacial tension of the system significantly decline due to the excellent action of ILs like surfactants. Under the same conditions, the interfacial activity appears reasonably in the order of [C16mim][I] > [C16mim][Br] > [C16mim][Cl] ? [C14mim][Br] > [C14mim][Cl] ? [C12mim][Cl], consistent with alkyl chain length and the kind of halide anions. Molecules of the used ILs exhibit ideal adsorption within the used concentrations and the data were satisfactorily reproduced by the Szyszkowski adsorption model. Consistently, effectiveness of adsorption increases with the anion polarization and the number of carbon atoms in alkyl chain; however, temperature leads this parameter to decrease. On the other hand, adsorption tendency increases with either of anion polarization, alkyl chain length and temperature. Meanwhile, negative standard free energies were consistent and showed spontaneous adsorptions.
Regulating the mesogenic properties of imidazolium salts by modifying N3-substituents
Wang, Meng,Pan, Xu,Chen, Jian,Dai, Songyuan
, p. 1884 - 1890 (2015)
In this study, a series of imidazolium salts with different N3-substituents (3-position: methyl, vinyl, ethyl, n-propyl, n-butyl)-based ionic-liquid crystals with iodide as counterion (ILCs) are synthesized and characterized, with the aim of regulating the mesogenic properties of imidazolium salts. The imidazolium salts-based ionic-liquid crystals are characterized by thermal analysis, polarized optical microscopy, X-ray powder diffraction, and single-crystalline diffraction. Liquid crystalline phase with a Smectic A phase interdigitated bilayer structure is observed. The mesophase temperature range decreases with the increase of the alkyl chain length of N3-substituent. While when vinyl is attached to the N3 position, intermolecular π-π interactions are formed in adjacent layers, which exert a positive effect on the formation of mesophase. The layer-spacing of imidazolium salts keeps increasing with the increase of the alkyl chain length attached to both the N1 and N3 positions, and gradually decreases with the increasing temperature in liquid crystalline phase. The 1-alkyl-3-vinylimidazolium salt has the smallest layer-spacing, due to the intermolecular π-π interactions between the vinyl and imidazolium rings in adjacent layers.
The fluid-mosaic model, homeoviscous adaptation, and ionic liquids: Dramatic lowering of the melting point by side-chain unsaturation
Murray, Samuel M.,O'Brien, Richard A.,Mattson, Kaila M.,Ceccarelli, Christopher,Sykora, Richard E.,West, Kevin N.,Davis Jr., James H.
body text, p. 2755 - 2758 (2010/07/06)
(Figure Presented) Defying conventional wisdom: Ionic liquids (ILs) with long, unsaturated alkyl appendages (see top structure) defy established trends that link long ion-bound alkyl groups to higher melting points. The new ILs are also less viscous than a saturated standard (see bottom structure) at the same temperature. These features parallel those that underpin homeoviscous adaptation in certain organisms and are indirectly supportive of a fluid-mosaiclike nanoscale character.
