scholarly journals The origin of surfactant amphiphilicity and self-assembly in protic ionic liquids

2015 ◽  
Vol 6 (11) ◽  
pp. 6189-6198 ◽  
Author(s):  
Andrew Dolan ◽  
Rob Atkin ◽  
Gregory G. Warr

Surfactant alkyl chain, head-group and counterion solvation in protic ionic liquids differs from water, affecting micelle formation and structure.

2016 ◽  
Vol 69 (11) ◽  
pp. 1254 ◽  
Author(s):  
Jiequn Wu ◽  
Tianxiang Yin ◽  
Shaoxiong Shi ◽  
Weiguo Shen

The systematic investigation of the aggregation behaviours of newly synthesised surface-active ionic liquids 1-alkyl-3-methylimidazolium bis(2-ethylhexyl)sulfosuccinate ([Cnmim][AOT], n = 2, 3, 5, 6, 7) by various techniques is reported. The critical aggregation concentrations (CACs) and the standard Gibbs free energies of aggregation () were determined from measurements on conductivity, fluorescence, and surface tension, which suggested a stronger self-assembly ability in the bulk solution for [Cnmim][AOT] surfactants with longer alkyl chain cations. An interesting structure transition driven by the penetration of the imidazolium cation into the aggregate when n > 4 was found by analysis of the variations of the values of CAC, , the degree of counter ion binding (β), and the micropolarity (I1/I3) immediately after the CAC with changing alkyl chain length of the imidazolium cation, which was further confirmed by 1H NMR measurements.


2019 ◽  
Vol 21 (13) ◽  
pp. 6810-6827 ◽  
Author(s):  
Dilek Yalcin ◽  
Calum J. Drummond ◽  
Tamar L. Greaves

High throughput methods were used to investigate ionic liquid containing solutions to provide systematic data of a broad compositional space. We have principally focused on the surface tension, apparent pH and liquid nanostructure to identify potential self-assembly and protein stabilizing ability of solvent systems.


2019 ◽  
Vol 123 (18) ◽  
pp. 4044-4054 ◽  
Author(s):  
Iqbaal Abdurrokhman ◽  
Khalid Elamin ◽  
Olesia Danyliv ◽  
Mohammad Hasani ◽  
Jan Swenson ◽  
...  

Processes ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. 742
Author(s):  
Nur Hidayah Zulaikha Othman Zailani ◽  
Normawati M. Yunus ◽  
Asyraf Hanim Ab Rahim ◽  
Mohamad Azmi Bustam

Ionic liquids which are often classified as low melting point salts have received significant attention from research groups and industries to be used in a wide range of applications. Many of these applications require thorough knowledge on the thermophysical properties of the ionic liquids before utilizing their full potentials in various fields. In this work, a series of alkylammonium cation and carboxylate anion-based room temperature protic ionic liquids (PILs) were synthesized by varying length of alkyl chain of the cation from diethyl to dibutyl combined with pentanoate, hexanoate and heptanoate anions. These ammonium-based PILs named as diethylammonium pentanoate [DEA][C5], diethylammonium hexanoate [DEA][C6], diethylammonium heptanoate [DEA][C7], dibutylammonium pentanoate [DBA][C5], dibutylammonium hexanoate [DBA][C6] and dibutylammonium heptanoate [DBA][C7] were characterized using Nuclear Magnetic Resonance (NMR) spectroscopy. The thermophysical properties of the PILs namely density, dynamic viscosity and refractive index were measured and analyzed. Density, ρ and dynamic viscosity, η were determined at T = (293.15 to 363.15) K and refractive index, nD was measured at T = (293.15 to 333.15) K. The fitting parameters are proposed for the empirical correlations of density, dynamic viscosity and refractive index. The values of thermal expansion coefficient, αp, molecular volume, Vm, standard entropy, S° and lattice potential energy, Upot also have been calculated by using the specified equations. The thermal decomposition temperature, Td was also determined using a thermogravimetric analyzer (TGA) while the differential scanning calorimetry (DSC) technique provided the glass transition, Tg, melting point, Tm and crystallization, Tc temperatures of the PILs. The experimental results revealed that the dependency of the experimental values namely the ρ, η, nD, and Td on the alkyl chain of the anion, size of the cations and the temperature of measurement.


Soft Matter ◽  
2020 ◽  
Vol 16 (41) ◽  
pp. 9456-9470
Author(s):  
Dilek Yalcin ◽  
Calum J. Drummond ◽  
Tamar L. Greaves

Protic ionic liquids (PILs) are the largest and most tailorable known class of non-aqueous solvents which possess the ability to support amphiphile self-assembly.


2011 ◽  
Vol 64 (2) ◽  
pp. 180 ◽  
Author(s):  
Jiayi Wang ◽  
Tamar L. Greaves ◽  
Danielle F. Kennedy ◽  
Asoka Weerawardena ◽  
Gonghua Song ◽  
...  

The thermal phase transitions and physicochemical properties of a series of 21 amino acid-derived protic ionic liquids and four protic molten salts have been investigated. Structure–property comparisons for this series were investigated for alkyl- and cyclic amino acid cations, and ethoxy and methoxy groups on the cation, combined with nitrate or various carboxylate-containing anions. All the protic fused salts were found to be ‘fragile’. Most of the protic fused salts exhibited a glass transition, with the transition temperatures ranging from –90° to –42°C. Viscosities and conductivities ranged from 0.03 to 15.46 Pa s and 0.02 to 2.20 mS cm–1 at 25°C respectively. The protic ionic liquids alanine methyl ester glycolate, proline methyl ester nitrate, and proline methyl ester glycolate were found to be capable of supporting amphiphile self-assembly. Lamellar or hexagonal liquid crystalline phases were observed with the cationic surfactant hexadecyltrimethylammonium bromide and the non-ionic surfactant Myverol 18–99K.


2017 ◽  
Vol 115 (13) ◽  
pp. 1582-1589 ◽  
Author(s):  
M. Campetella ◽  
M. Macchiagodena ◽  
L. Gontrani ◽  
B. Kirchner

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