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Yeboah J, Metott ZJ, Butch CM, Hillesheim PC, Mirjafari A. Are nature's strategies the solutions to the rational design of low-melting, lipophilic ionic liquids? Chem Commun (Camb) 2024; 60:3891-3909. [PMID: 38420843 PMCID: PMC10994746 DOI: 10.1039/d3cc06066g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Ionic liquids (ILs) have emerged as a new class of materials, displaying a unique capability to self-assemble into micelles, liposomes, liquid crystals, and microemulsions. Despite evident interest, advancements in the controlled formation of amphiphilic ILs remain in the early stages. Taking inspiration from nature, we introduced the concept of lipid-like (or lipid-inspired) ILs more than a decade ago, aiming to create very low-melting, highly lipophilic ILs that are potentially bio-innocuous - a combination of attributes that is frequently antithetical but highly desirable from several application-specific standpoints. Lipid-like ILs are a subclass of functional organic liquid salts that include a range of lipidic side chains such as saturated, unsaturated, linear, branched, and thioether while retaining melting points below room temperature. It was observed in several homologous series of [Cnmim] ILs that elongation of N-appended alkyl chains to greater than seven carbons leads to a substantial increase in melting point (Tm) - which is the most characteristic feature of ILs. Accordingly, it is challenging to develop ILs with low Tm values while preserving their hydrophobicity and self-organizing properties. We found that two alternative Tm depressive approaches are useful. One of these is the replacement of the double bonds with thioether moieties in the alkyl chains, as detailed in several published papers detailing the chemistry of these ILs. Employing thiol-ene and thiol-yne click reactions is a facile, robust, and orthogonal method to overcome the challenges associated with the synthesis of alkyl thioether-functionalized ILs. The second approach involves replacing the double bonds with the cisoid cyclopropyl motif, mimicking the strategy used by certain organisms to modulate cell membrane fluidity. This discovery has the potential to greatly impact the utilization of lipid-like ILs in various applications, including gene delivery, lubricants, heat transfer fluids, and haloalkane separations, among others. This feature article presents a concise, historical overview, highlighting key findings from our work while offering speculation about the future trajectory of this de novo class of soft organic-ion materials.
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Affiliation(s)
- John Yeboah
- Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, USA.
| | - Zachary J Metott
- Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, USA.
| | - Christopher M Butch
- Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, USA.
| | - Patrick C Hillesheim
- Department of Chemistry and Physics, Ave Maria University, Ave Maria, Florida, 34142, USA.
| | - Arsalan Mirjafari
- Department of Chemistry, State University of New York at Oswego, Oswego, New York 13126, USA.
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2
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Wojcieszak M, Syguda A, Karolak M, Pałkowski Ł, Materna K. Quaternary ammonium salts based on caprylic acid as antimicrobial and surface-active agents. RSC Adv 2023; 13:34782-34797. [PMID: 38035245 PMCID: PMC10685092 DOI: 10.1039/d3ra07127h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 11/21/2023] [Indexed: 12/02/2023] Open
Abstract
In this work, amidequats and esterquats based on caprylic acid were investigated as promising compounds with surface properties and biological activity that are in harmony with the principles of green chemistry. Herein, caprylic acid, which is an essential component of the above compounds, is a noteworthy natural resource. Structural analysis was performed with the amphiphilic cations of the tested amidequats and esterquats, revealing two distinct factors, i.e., the elongation of the alkyl chain and the presence of two different functional groups; these factors undoubtedly affect the desired biological activity. These compounds were synthesized and characterized in terms of their physicochemical properties, among which surface activity is pivotal. In addition, the surfaces of the tested compounds were investigated through a detailed topographical analysis. The obtained results suggested that the esterquats exhibited higher surface activity, wettability and foamability than the amidequats. Antimicrobial studies, on the other hand, are not as conclusive. For shorter chains, esterquats are more active than amidequats, while for longer chains (over C12), the trend was the opposite. The amidequats and esterquats presented in this research may be a potential good replacement for antimicrobial formulations or as alternatives to surface-active agents used in industry.
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Affiliation(s)
- Marta Wojcieszak
- Poznan University of Technology, Faculty of Chemical Technology Berdychowo 4 60-965 Poznan Poland
| | - Anna Syguda
- Poznan University of Technology, Faculty of Chemical Technology Berdychowo 4 60-965 Poznan Poland
| | - Maciej Karolak
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Nicolaus Copernicus University Jurasza 2 85-089 Bydgoszcz Poland
| | - Łukasz Pałkowski
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Nicolaus Copernicus University Jurasza 2 85-089 Bydgoszcz Poland
| | - Katarzyna Materna
- Poznan University of Technology, Faculty of Chemical Technology Berdychowo 4 60-965 Poznan Poland
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3
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Zuo Y, Lv J, Wei N, Chen X, Tong J. Effect of anions and cations on the self-assembly of ionic liquid surfactants in aqueous solution. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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4
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Marlow JB, Atkin R, Warr GG. How Does Nanostructure in Ionic Liquids and Hybrid Solvents Affect Surfactant Self-Assembly? J Phys Chem B 2023; 127:1490-1498. [PMID: 36786772 DOI: 10.1021/acs.jpcb.2c07458] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Ionic liquids (ILs) have recently emerged as novel classes of solvents that support surfactant self-assembly into micelles, liquid crystals, and microemulsions. Their low volatility and wide liquid stability ranges make them attractive for many diverse applications, especially in extreme environments. However, the number of possible ion combinations makes systematic investigations both challenging and rare; this is further amplified when mixtures are considered, whether with water or other H-bonding components such as those found in deep eutectics. In this Perspective we examine what factors determine amphiphilicity, solvophobicity and solvophilicity, in ILs and related exotic environments, in what ways these differ from water, and how the underlying nanostructure of the liquid itself affects the formation and structure of micelles and other self-assembled materials.
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Affiliation(s)
- Joshua B Marlow
- School of Chemistry and Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia
| | - Rob Atkin
- School of Molecular Sciences, The University of Western Australia, Perth, Western Australia 6009, Australia
| | - Gregory G Warr
- School of Chemistry and Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia
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Barik S, Chakraborty M, Mahapatra A, Sarkar M. Choline chloride and ethylene glycol based deep eutectic solvent (DES) versus hydroxyl functionalized room temperature ionic liquids (RTILs): assessing the differences in microscopic behaviour between the DES and RTILs. Phys Chem Chem Phys 2022; 24:7093-7106. [PMID: 35262105 DOI: 10.1039/d1cp05010a] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
With the aim of understanding the differences in the behavior of deep eutectic solvents (DESs) and room temperature ionic liquids (RTILs) in terms of their structure, dynamics, and intra- and intermolecular interactions, three different ILs and one DES having similar functionalities (hydroxyl) have been investigated by using both ensembled average and single-molecule spectroscopic techniques. Specifically, for this purpose, a choline chloride based DES (ethaline) and three hydroxyl functionalized ILs (1-(2-hydroxyethyl)-3-imidazolium bis(trifluoromethanesulfonyl)imide ([OHEMIM][NTF2]), N-(2-hydroxyl ethyl)-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([OHEMPy][NTf2]), and N-(2-hydroxyethyl)-N,N-dimethylpropan-1-aminium bis(trifluoromethanesulfonyl)imide ([OHC3CH][NTf2])) are employed and investigated by EPR, time-resolved fluorescence, NMR and FCS studies. Estimation of polarity through EPR spectroscopy has revealed that the hydroxyl ILs employed in these studies are hyper-polar (close to water) in nature, whereas the polarity of the DES is found to be close to those of aliphatic polyhydroxy-alcohols. Interestingly, both time-resolved fluorescence anisotropy and FCS studies on these systems have suggested that the hydroxyl ILs are more dynamically heterogeneous than the DES. More interestingly, PFG-NMR measurements have indicated that the fluid structure of ethaline is relatively more associated as compared to those of the ILs despite the fact that all the cations have the same hydroxyl functionalities. All these investigations have essentially demonstrated that, despite having similar functionalities, both the DES and hydroxyl ILs employed in the present study exhibit microscopic behaviours that are significantly different from each other, indicating the interplay of various intermolecular interactions within the constituent species in governing the behaviours of these solvent systems.
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Affiliation(s)
- Sahadev Barik
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute, Jatni, Khurda, Bhubaneswar, 752050, Odisha, India. .,Centre of Interdisciplinary Science (CIS), NISER, Bhubaneswar, Jatni, Khurda, 752050, Odisha, India
| | - Manjari Chakraborty
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute, Jatni, Khurda, Bhubaneswar, 752050, Odisha, India. .,Centre of Interdisciplinary Science (CIS), NISER, Bhubaneswar, Jatni, Khurda, 752050, Odisha, India
| | - Amita Mahapatra
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute, Jatni, Khurda, Bhubaneswar, 752050, Odisha, India. .,Centre of Interdisciplinary Science (CIS), NISER, Bhubaneswar, Jatni, Khurda, 752050, Odisha, India
| | - Moloy Sarkar
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), An OCC of Homi Bhabha National Institute, Jatni, Khurda, Bhubaneswar, 752050, Odisha, India. .,Centre of Interdisciplinary Science (CIS), NISER, Bhubaneswar, Jatni, Khurda, 752050, Odisha, India
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Reddy TDN, Mallik BS. Hydrogen Bond Kinetics, Ionic Dynamics, and Voids in the Binary Mixtures of Protic Ionic Liquids with Alkanolamines. J Phys Chem B 2021; 125:5587-5600. [PMID: 34010564 DOI: 10.1021/acs.jpcb.0c10658] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Classical molecular dynamics simulations were used to investigate the structural and dynamical properties of the mixtures of ionic liquids (ILs) with the conjugate forms of the cation in a 1:1 molar ratio. The experimental studies suggested the combination of ethanolamines and ILs as novel absorbents for acidic gases such as CO2 and H2S, which provide the advantage of efficient absorption of gases at low pressures. However, the microscopic properties of the ionic mixtures are not studied. From our computational investigations, the densities of mixtures are reported and compared with the experimental results. The structural evolution of mixtures is reported by radial distribution functions, coordination numbers, void analysis, and spatial distribution functions. The mixtures' dynamic properties were studied by analyzing the hydrogen bond, ion-pair, and ion-cage lifetimes of the system. Monoethanolammonium and triethanolammonium ILs show different types of spatial distribution functions. The cations have lesser effect on dynamics compared with anions. The charge on the anion greatly affects the dynamics of mixtures. The dianion mixtures show slower dynamics than the monoanionic mixtures. The hydrogen bonding between cations and anions is stronger than that between cations and neutral molecules due to strong coulombic attractive forces. The cations spend more time around the dianions as compared to monoanions. The distributions of voids show that the void sizes are smaller in triethanolamine-based mixtures. The sulfobenzoate-based mixtures show voids smaller than those of pyridine-3-carboxylate-based mixtures due to more available free space between the entities, which facilitates the overall dynamics.
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Affiliation(s)
- Th Dhileep N Reddy
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy 502285, Telangana, India
| | - Bhabani S Mallik
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy 502285, Telangana, India
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7
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Farooq U, Malik NA, Shalla AH. Thermodynamics of cosolvent effect of surface-active ionic liquids on the micellization of conventional surfactant. Colloid Polym Sci 2021. [DOI: 10.1007/s00396-021-04845-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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8
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Li Q, Wang X, Zhuang W, Yao M, Pan Y, Chen X. Spacer length effect on the aggregation behaviours of gemini surfactants in EAN. Colloid Polym Sci 2021. [DOI: 10.1007/s00396-020-04795-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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9
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Zhuang W, Zhao C, Pan Y, Li Q. Self-assembly of an imidazolium surfactant in aprotic ionic liquids. 2. More than solvents. SOFT MATTER 2021; 17:3494-3502. [PMID: 33657203 DOI: 10.1039/d1sm00039j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
As tailorable solvents, the physiochemical properties of ionic liquids can be tuned by the structure of ions. Herein, we investigate the structural effects of ILs on the self-assembly of surfactants. It has been confirmed that the cationic surfactant 1-hexadecyl-3-methylimidazolium bromide (C16mimBr) can self-assemble into micellar and lamellar lyotropic liquid crystal phases in the aprotic ionic liquid (AIL) 1-ethyl-3-methylimidazolium tetrafluoroborate ([Emim]BF4). In this work, we explore the aggregation behaviours in AILs with different alkyl chains on the imidazolium group, i.e., 1-propyl-3-methylimidazolium tetrafluoroborate ([Pmim]BF4), 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4), 1-hexyl-3-methylimidazolium tetrafluoroborate ([Hmim]BF4) and 1-octyl-3-methylimidazolium tetrafluoroborate ([Omim]BF4). With the increase of the cation chain length, AILs have better solubility of the solvophobic part of the surfactants and hence a weaker driving force for self-assembly. Therefore, the critical micellization concentration of C16mimBr in AILs increases as confirmed by the surface tension and small angle X-ray scattering characterizations. More interesting things happen to the phase behaviours. Besides the micellar and lamellar lyotropic liquid crystal phases, a hexagonal lyotropic liquid crystal phase is formed in [Pmim]BF4 while hexagonal and bicontinuous cubic lyotropic liquid crystal phases are formed in [Bmim]BF4, [Hmim]BF4 and [Omim]BF4. It is surprising to observe richer phase behaviours in solvents of lower cohesive energy. The detailed structural information of various aggregates has been obtained by small-angle X-ray scattering. It is demonstrated that AILs work as not only solvents but also co-surfactants.
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Affiliation(s)
- Wenchang Zhuang
- School of Materials and Chemical Engineering, Xuzhou University of Technology, Xuzhou 221018, P. R. China.
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10
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Bryant SJ, Garcia A, Clarke RJ, Warr GG. Selective ion transport across a lipid bilayer in a protic ionic liquid. SOFT MATTER 2021; 17:2688-2694. [PMID: 33533359 DOI: 10.1039/d0sm02225j] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Ionic liquids (ILs) have exhibited enormous potential as electrolytes, designer solvents and reaction media, as well as being surprisingly effective platforms for amphiphile self-assembly and for preserving structure of complex biomolecules. This has led to their exploration as media for long-term biopreservation and in biosensors, for which their viability depends on their ability to sustain both structure and function within complex, multicomponent nanoscale compartments and assemblies. Here we show that a tethered lipid bilayer can be assembled directly in a purely IL environment that retains its structure upon exchange between IL and aqueous buffer, and that the membrane transporter valinomycin can be incorporated so as to retain its functionality and cation selectivity. This paves the way for the development of long-lived, non-aqueous microreactors and sensor assemblies, and demonstrates the potential for complex proteins to retain functionality in non-aqueous, ionic liquid solvents.
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Affiliation(s)
- Saffron J Bryant
- School of Chemistry, The University of Sydney, NSW 2006, Australia and School of Science, RMIT University, Melbourne, Victoria 3001, Australia.
| | - Alvaro Garcia
- School of Chemistry, The University of Sydney, NSW 2006, Australia and School of Life Sciences, University of Technology Sydney, NSW 2007, Australia
| | - Ronald J Clarke
- School of Chemistry, The University of Sydney, NSW 2006, Australia
| | - Gregory G Warr
- School of Chemistry, The University of Sydney, NSW 2006, Australia and University of Sydney Nano Institute, The University of Sydney, NSW 2006, Australia
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11
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Yalcin D, Drummond CJ, Greaves TL. Lyotropic liquid crystal phase behavior of a cationic amphiphile in aqueous and non-stoichiometric protic ionic liquid mixtures. SOFT MATTER 2020; 16:9456-9470. [PMID: 32966534 DOI: 10.1039/d0sm01298j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
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. However, little is known about the effect of solvent additives on this ability. In this study, the lyotropic liquid crystal phase (LLCP) behavior of the cationic surfactant cetyltrimethylammonium bromide (CTAB) was investigated in the model PILs of ethylammonium nitrate (EAN) and ethanolammonium nitrate (EtAN), and derived multi-component solvent systems containing them to determine phase formation and diversity with changing solvent composition. The solvent systems were composed of water, nitric acid and ethylamine (or ethanolamine), with 26 unique compositions for each PIL covering the apparent pH and ionicity ranges of 0-13.5 and 0-11 M, respectively. The LLCPs were studied using cross polarized optical microscopy (CPOM) and small and wide-angle X-ray scattering (SAXS/WAXS). Partial phase diagrams were constructed for CTAB concentrations of 50 wt% and 70 wt% in the temperature range of 25 °C to 75 °C to characterise the effect of surfactant concentration and temperature on the LLCPs in each solvent environment. Normal micellar (L1), hexagonal (H1) and bicontinuous cubic (V1) phases were identified at both surfactant concentrations, and from temperatures as low as 35 °C, with large variations dependent on the solvent composition. The thermal stability and diversity of phases were greater and broader in solvent compositions with excess precursor amines present compared to those in the neat PILs. In acid-rich solvent combinations, the same phase diversity was found, though with reduced onset temperatures of phase formation; however, some structural changes were observed which were attributed to oxidation/decomposition of CTAB in a nitric acid environment. This study showed that the ability of PIL solutions to support amphiphile self-assembly can readily be tuned, and that the ability of PILs to promote amphiphile self-assembly is robust, even with other solvent species present.
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Affiliation(s)
- Dilek Yalcin
- School of Science, College of Science, Engineering and Health, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia.
| | - Calum J Drummond
- School of Science, College of Science, Engineering and Health, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia.
| | - Tamar L Greaves
- School of Science, College of Science, Engineering and Health, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia.
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Warr GG, Atkin R. Solvophobicity and amphiphilic self-assembly in neoteric and nanostructured solvents. Curr Opin Colloid Interface Sci 2020. [DOI: 10.1016/j.cocis.2019.12.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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13
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DTAB micelle formation in ionic liquid/water mixtures is determined by ionic liquid cation structure. J Colloid Interface Sci 2019; 552:597-603. [DOI: 10.1016/j.jcis.2019.05.082] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 05/24/2019] [Accepted: 05/25/2019] [Indexed: 11/21/2022]
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14
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Catanionic and chain-packing effects on surfactant self-assembly in the ionic liquid ethylammonium nitrate. J Colloid Interface Sci 2019; 540:515-523. [DOI: 10.1016/j.jcis.2019.01.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/11/2019] [Accepted: 01/11/2019] [Indexed: 11/19/2022]
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15
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Pei Y, Hao L, Ru J, Zhao Y, Wang H, Bai G, Wang J. The self-assembly of ionic liquids surfactants in ethanolammonium nitrate ionic liquid. J Mol Liq 2018. [DOI: 10.1016/j.molliq.2018.01.095] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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16
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Li Q, Yao M, Yue X, Chen X. Effects of a Spacer on the Phase Behavior of Gemini Surfactants in Ethanolammonium Nitrate. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:4328-4336. [PMID: 28415837 DOI: 10.1021/acs.langmuir.7b00927] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The aggregation behavior of quaternary ammonium gemini surfactants (12-s-12) in a protic ionic liquid, ethanolammonium nitrate (EOAN), was investigated by small-angle X-ray scattering, freeze-fracture transmission electron microscopy, polarized optical microscopy, and rheological measurements. The rarely reported nonaqueous two phases in the ionic liquid were observed at lower 12-s-12 concentrations. The upper phase was composed of micelles, whereas only the surfactant unimers or multimers were detected in the low phase. At higher 12-s-12 concentrations, different aggregates were formed. The lamellar phase was observed in the 12-2-12/EOAN system, whereas the normal hexagonal phases in 12-s-12/EOAN (s = 3, 4, 5, 6, 8) systems and the micellar phase in the 12-10-12/EOAN system were observed. Such a dramatic phase transition induced by the spacer chain length was due to the unique solvent characteristics of EOAN compared to those of water and its counterpart ethylammonium nitrate.
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Affiliation(s)
- Qintang Li
- Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education , Jinan 250100, China
| | - Meihuan Yao
- School of Chemistry and Chemical Engineering, Henan Normal University , Xinxiang 453007, China
| | - Xiu Yue
- Laboratory of Environmental Sciences and Technology, Xinjiang Technical Institute of Physics & Chemistry, Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences , Urumqi 830011, China
| | - Xiao Chen
- Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education , Jinan 250100, China
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17
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Bryant SJ, Wood K, Atkin R, Warr GG. Effect of protic ionic liquid nanostructure on phospholipid vesicle formation. SOFT MATTER 2017; 13:1364-1370. [PMID: 28111683 DOI: 10.1039/c6sm02652d] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The formation of bilayer-based lyotropic liquid crystals and vesicle dispersions by phospholipids in a range of protic ionic liquids has been investigated by polarizing optical microscopy using isothermal penetration scans, differential scanning calorimetry, and small angle X-ray and neutron scattering. The stability and structure of both lamellar phases and vesicle dispersions is found to depend primarily on the underlying amphiphilic nanostructure of the ionic liquid itself. This finding has significant implications for the use of ionic liquids in soft and biological materials and for biopreservation, and demonstrates how vesicle structure and properties can be controlled through selection of cation and anion. For a given ionic liquid, systematic trends in bilayer thickness, chain-melting temperature and enthalpy increase with phospholipid acyl chain length, paralleling behaviour in aqueous systems.
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Affiliation(s)
- Saffron J Bryant
- School of Chemistry, F11, The University of Sydney, NSW 2006, Australia.
| | - Kathleen Wood
- Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC NSW 2232, Australia
| | - Rob Atkin
- Discipline of Chemistry, The University of Newcastle, Newcastle, NSW 2308, Australia
| | - Gregory G Warr
- School of Chemistry, F11, The University of Sydney, NSW 2006, Australia.
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18
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Selwent A, Łuczak J. Micellar aggregation of Triton X-100 surfactant in imidazolium ionic liquids. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.05.081] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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19
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Bharmoria P, Kumar A. Unusually high thermal stability and peroxidase activity of cytochrome c in ionic liquid colloidal formulation. Chem Commun (Camb) 2016; 52:497-500. [DOI: 10.1039/c5cc05722a] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
All ionic liquid-based colloidal formulation as a thermally stable medium for enzyme biocatalysis.
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Affiliation(s)
- Pankaj Bharmoria
- AcSIR
- CSIR-Central Salt and Marine Chemicals Research Institute
- Bhavangar-364002
- India
| | - Arvind Kumar
- AcSIR
- CSIR-Central Salt and Marine Chemicals Research Institute
- Bhavangar-364002
- India
- Salt and Marine Chemicals Division
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20
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Murphy T, Hayes R, Imberti S, Warr GG, Atkin R. Ionic liquid nanostructure enables alcohol self assembly. Phys Chem Chem Phys 2016; 18:12797-809. [DOI: 10.1039/c6cp01739h] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Weakly structured solutions are formed from mixtures of one or more amphiphiles and a polar solvent (usually water), and often contain additional organic components.
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Affiliation(s)
- Thomas Murphy
- Priority Research Centre for Advanced Fluids and Interfaces
- Newcastle Institute for Energy & Resources
- University of Newcastle
- Callaghan
- Australia
| | - Robert Hayes
- Priority Research Centre for Advanced Fluids and Interfaces
- Newcastle Institute for Energy & Resources
- University of Newcastle
- Callaghan
- Australia
| | | | | | - Rob Atkin
- Priority Research Centre for Advanced Fluids and Interfaces
- Newcastle Institute for Energy & Resources
- University of Newcastle
- Callaghan
- Australia
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Dolan A, Atkin R, Warr GG. The origin of surfactant amphiphilicity and self-assembly in protic ionic liquids. Chem Sci 2015; 6:6189-6198. [PMID: 30090234 PMCID: PMC6054141 DOI: 10.1039/c5sc01202c] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Accepted: 08/04/2015] [Indexed: 11/21/2022] Open
Abstract
The nature of amphiphilic self-assembly in alkylammonium protic ionic liquids (PILs) is examined by systematically varying the ionic structure and composition, H-bonding capacity, and nanostructure of both the PIL and micelle-forming cationic surfactant, and contrasted with self-assembly in water. Using small-angle neutron scattering, micelle structure and concentrations are determined for primary - quaternary dodecylammonium salts in nitrate and thiocyanate PILs. While the solvophobic driving force depends only on the average polarity of the PIL, surprisingly strong, specific interactions of the head group and counterion with the PIL H-bond network are found. This suggests the importance of developing designer amphiphiles for assembling soft matter structures in PILs.
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Affiliation(s)
- Andrew Dolan
- School of Chemistry , The University of Sydney , Sydney , NSW 2006 , Australia .
| | - Rob Atkin
- Centre for Advanced Particle Processing and Transport , Chemistry Building , The University of Newcastle , Callaghan , NSW 2308 , Australia
| | - Gregory G Warr
- School of Chemistry , The University of Sydney , Sydney , NSW 2006 , Australia .
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22
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Greaves TL, Drummond CJ. Protic Ionic Liquids: Evolving Structure-Property Relationships and Expanding Applications. Chem Rev 2015; 115:11379-448. [PMID: 26426209 DOI: 10.1021/acs.chemrev.5b00158] [Citation(s) in RCA: 513] [Impact Index Per Article: 57.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Tamar L Greaves
- School of Applied Sciences, College of Science, Engineering and Health, RMIT University , GPO Box 2476, Melbourne, Victoria 3001, Australia
| | - Calum J Drummond
- School of Applied Sciences, College of Science, Engineering and Health, RMIT University , GPO Box 2476, Melbourne, Victoria 3001, Australia
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23
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Micelle formation of Tween 20 nonionic surfactant in imidazolium ionic liquids. Colloids Surf A Physicochem Eng Asp 2015. [DOI: 10.1016/j.colsurfa.2015.02.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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24
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Effect of [C n mim][Br] Based Ionic Liquids on the Aggregation Behavior of Tetradecyltrimethylammonium Bromide in Aqueous Medium. J SOLUTION CHEM 2015. [DOI: 10.1007/s10953-015-0318-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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25
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Chen Z, FitzGerald PA, Kobayashi Y, Ueno K, Watanabe M, Warr GG, Atkin R. Micelle Structure of Novel Diblock Polyethers in Water and Two Protic Ionic Liquids (EAN and PAN). Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b00082] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Zhengfei Chen
- Newcastle
Institute for Energy and Resources, The University of Newcastle, Callaghan, NSW Australia
| | - Paul A. FitzGerald
- School
of Chemistry, The University of Sydney, Sydney, NSW 2006 Australia
| | - Yumi Kobayashi
- Department
of Chemistry and Biotechnology, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Kazuhide Ueno
- Department
of Chemistry and Biotechnology, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Masayoshi Watanabe
- Department
of Chemistry and Biotechnology, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Gregory G. Warr
- School
of Chemistry, The University of Sydney, Sydney, NSW 2006 Australia
| | - Rob Atkin
- Newcastle
Institute for Energy and Resources, The University of Newcastle, Callaghan, NSW Australia
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26
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Chen Z, Greaves TL, Caruso RA, Drummond CJ. Effect of cosolvents on the self-assembly of a non-ionic polyethylene oxide–polypropylene oxide–polyethylene oxide block copolymer in the protic ionic liquid ethylammonium nitrate. J Colloid Interface Sci 2015; 441:46-51. [DOI: 10.1016/j.jcis.2014.11.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 10/29/2014] [Accepted: 11/02/2014] [Indexed: 11/27/2022]
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27
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Docampo-Álvarez B, Gómez-González V, Méndez-Morales T, Carrete J, Rodríguez JR, Cabeza Ó, Gallego LJ, Varela LM. Mixtures of protic ionic liquids and molecular cosolvents: A molecular dynamics simulation. J Chem Phys 2014; 140:214502. [DOI: 10.1063/1.4879660] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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28
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Topolnicki IL, FitzGerald PA, Atkin R, Warr GG. Effect of Protic Ionic Liquid and Surfactant Structure on Partitioning of Polyoxyethylene Non-ionic Surfactants. Chemphyschem 2014; 15:2485-9. [DOI: 10.1002/cphc.201402087] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Indexed: 11/05/2022]
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29
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Javadian S, Nasiri F, Heydari A, Yousefi A, Shahir AA. Modifying Effect of Imidazolium-Based Ionic Liquids on Surface Activity and Self-Assembled Nanostructures of Sodium Dodecyl Sulfate. J Phys Chem B 2014; 118:4140-50. [DOI: 10.1021/jp5010049] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Soheila Javadian
- Department
of Chemistry, Faculty of Science, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran
| | - Fayezeh Nasiri
- Department
of Chemistry, Faculty of Science, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran
| | - Akbar Heydari
- Department
of Chemistry, Faculty of Science, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran
| | - Ali Yousefi
- Department
of Chemistry, Faculty of Science, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran
| | - Afshin Asadzadeh Shahir
- Department
of Chemistry, Faculty of Science, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran
- Division
of Chemical Engineering, School of Engineering, The University of Queensland, Brisbane, 4072 Queensland, Australia
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30
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Li Q, Wang X, Yue X, Chen X. Phase transition of a quaternary ammonium Gemini surfactant induced by minor structural changes of protic ionic liquids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:1522-1530. [PMID: 24455981 DOI: 10.1021/la404826k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The aggregation behaviors of a Gemini surfactant [C12H25(CH3)2N(+)(CH2)2N(+)(CH3)2C12H25]Br2(-) (12-2-12) in two protic ionic liquids (PILs), propylammonium nitrate (PAN) and butylammonium nitrate (BAN), were investigated by means of several experimental techniques including small and wide-angle X-ray scattering, the polarized optical microscopy and the rheological measurement. Compared to those in ethylammonium nitrate (EAN), the minor structural changes with only one or two methylene units (-CH2-) increase in cationic chain length of PIL, result in a dramatic phase transition of formed aggregates. The critical micellization concentration was increased in PAN, while no micelle formation was detected in BAN. A normal hexagonal phase was observed in the 12-2-12/PAN system, while the normal hexagonal, bicontinuous cubic, and lamellar phases were mapped in the 12-2-12/BAN system. Such aggregation behavior changes can be ascribed to the weaker solvophobic interactions of 12-2-12 in PAN and BAN. The unique molecular structure of 12-2-12 is also an important factor to highlight such a dramatic phase transition due to the PIL structure change.
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Affiliation(s)
- Qintang Li
- Key Laboratory of Colloid and Interface Chemistry, Shandong University Ministry of Education , Jinan, 250100, China
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31
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Méndez-Morales T, Carrete J, Cabeza Ó, Russina O, Triolo A, Gallego LJ, Varela LM. Solvation of lithium salts in protic ionic liquids: a molecular dynamics study. J Phys Chem B 2014; 118:761-70. [PMID: 24405468 DOI: 10.1021/jp410090f] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The structure of solutions of lithium nitrate in a protic ionic liquid with a common anion, ethylammonium nitrate, at room temperature is investigated by means of molecular dynamics simulations. Several structural properties, such as density, radial distribution functions, hydrogen bonds, spatial distribution functions, and coordination numbers, are analyzed in order to get a picture of the solvation of lithium cations in this hydrogen-bonded, amphiphilically nanostructured environment. The results reveal that the ionic liquid mainly retains its structure upon salt addition, the interaction between the ammonium group of the cation and the nitrate anion being only slightly perturbed by the addition of the salt. Lithium cations are solvated by embedding them in the polar nanodomains of the solution formed by the anions, where they coordinate with the latter in a solid-like fashion reminiscent of a pseudolattice structure. Furthermore, it is shown that the average coordination number of [Li](+) with the anions is 4, nitrate coordinating [Li](+) in both monodentate and bidentate ways, and that in the second coordination layer both ethylammonium cations and other lithiums are also found. Additionally, the rattling motion of lithium ions inside the cages formed by their neighboring anions, indicative of the so-called caging effect, is confirmed by the analysis of the [Li](+) velocity autocorrelation functions. The overall picture indicates that the solvation of [Li](+) cations in this amphiphilically nanostructured environment takes place by means of a sort of inhomogeneous nanostructural solvation, which we could refer to as nanostructured solvation, and which could be a universal solvation mechanism in ionic liquids.
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Affiliation(s)
- Trinidad Méndez-Morales
- Grupo de Nanomateriais e Materia Branda, Departamento de Física da Materia Condensada, Universidade de Santiago de Compostela , Campus Vida s/n, E-15782, Santiago de Compostela, Spain
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32
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Greaves TL, Drummond CJ. Solvent nanostructure, the solvophobic effect and amphiphile self-assembly in ionic liquids. Chem Soc Rev 2013; 42:1096-120. [PMID: 23165291 DOI: 10.1039/c2cs35339c] [Citation(s) in RCA: 253] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The ability of ionic liquids (ILs) to support amphiphile self-assembly into a range of mesophase structures has been established as a widespread phenomenon. From the ILs evaluated as self-assembly media, the vast majority have supported some lyotropic liquid crystal phase formation. Many neat ionic liquids have been shown to segregate into polar and non-polar domains to form a nanostructured liquid. A very strong correlation between the nanostructure of the ionic liquid and its characteristics as an amphiphile self-assembly solvent has been found. In this review we discuss ionic liquids as amphiphile self-assembly media, and identify trends that can be used to distinguish which ionic liquids are likely to have good promotion properties as self-assembly media. In particular these trends focus on the nanostructure of neat ionic liquids, their solvent cohesive energy density, and the related solvophobic effect. We forecast that many more ILs will be identified as amphiphile self-assembly solvents in the future.
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Affiliation(s)
- Tamar L Greaves
- CSIRO Materials Science and Engineering, Bag 10, Clayton VIC 3169, Australia.
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33
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Rao KS, So S, Kumar A. Vesicles and reverse vesicles of an ionic liquid in ionic liquids. Chem Commun (Camb) 2013; 49:8111-3. [DOI: 10.1039/c3cc44462g] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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34
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Wang X, Li Q, Chen X, Li Z. Effects of structure dissymmetry on aggregation behaviors of quaternary ammonium Gemini surfactants in a protic ionic liquid EAN. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:16547-16554. [PMID: 23140416 DOI: 10.1021/la304004u] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The aggregation behaviors of a series of dissymmetric cationic Gemini surfactants, [C(m)H(2m+1)(CH(3))(2)N(CH(2))(2)N(CH(3))(2)C(n)H(2n+1)]Br(2), designated as m-2-n (with a fixed m + n = 24, m = 16, 14, 12) have been investigated in a protic ionic liquid, ethylammonium nitrate (EAN). Surface tension, polarized optical microscopy (POM), small-angle X-ray scattering (SAXS), and rheological measurements are adopted to investigate the micellization and lyotropic liquid crystal (LLC) formation. The obtained results indicate that the structure dissymmetry plays an important role in aggregation process of m-2-n. With increasing degree of dissymmetry, the critical micellization concentration, the maximum reduction of solvent surface tension, and the minimum area occupied per surfactant molecule at the air/EAN interface all become smaller. The thermostability of formed LLCs is therefore improved because of the more compact molecules. These characteristics can be explained by the enhancement of solvophobic effect due to the increased structure dissymmetry of Gemini surfactants.
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Affiliation(s)
- Xudong Wang
- Key Laboratory of Colloid and Interface Chemistry, Shandong University, Ministry of Education, Jinan 250100, China
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35
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Capelo SB, Méndez-Morales T, Carrete J, López Lago E, Vila J, Cabeza O, Rodríguez JR, Turmine M, Varela LM. Effect of temperature and cationic chain length on the physical properties of ammonium nitrate-based protic ionic liquids. J Phys Chem B 2012; 116:11302-12. [PMID: 22947013 DOI: 10.1021/jp3066822] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report a systematic study of the effect of the cationic chain length and degree of hydrogen bonding on several equilibrium and transport properties of the first members of the alkylammonium nitrate protic ionic liquids (PILs) family (ethylammonium, propylammonium, and butylammonium nitrate) in the temperature range between 10 and 40 °C. These properties were observed by means of several experimental techniques, including density, surface tension, refractometry, viscosimetry, and conductimetry. The dilatation coefficients and compressibilities, as well as the Rao coefficients, were calculated, and an increase of these magnitudes with alkyl chain length was detected. Moreover, the surface entropies and enthalpies of the studied PILs were analyzed, and the temperature dependence of the surface tension was observed to be describable by means of a harmonic oscillator model with surface energies and critical temperatures that are increasing functions of the cationic chain length. Moreover, the refractive indexes were measured and the thermo-optic coefficient and Abbe numbers were calculated, and the contribution of the electrostrictive part seemed to dominate the temperature dependence of the electric polarization. The electric conductivity and the viscosity were measured and the influence of the degree of hydrogen bonding in the supercooled liquid region analyzed. Hysteresis loops were detected in freezing-melting cycles and the effect of the length of the alkyl chain of the cation on the size of the loop analyzed, showing that longer chains lead to a narrowing of the supercooled region. The temperature dependence of the conductivity was studied in the Vogel-Fulcher-Tamman (VFT) framework and the fragility indices, the effective activation energies, and the Vogel temperatures obtained. A high-temperature Arrhenius analysis was also performed, and the activation energies of conductivity and viscosity were calculated, showing that these transport processes are governed by two distinct mechanisms. The exponents of the fractional Walden rule for the different compounds were obtained. Finally, the ionicities and fragilities of the studied PILs were analyzed, proving that all the studied PILs are subionic and fragile liquids, with propylammonium nitrate showing the lowest fragility and the greater ionicity of all the studied compounds.
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Affiliation(s)
- S Bouzón Capelo
- Grupo de Nanomateriales y Materia Blanda, Departamento de Física de la Materia Condensada, Universidade de Santiago de Compostela, Campus Vida s/n E-15782, Santiago de Compostela, Spain
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36
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López-Barrón CR, Wagner NJ. Structural transitions of CTAB micelles in a protic ionic liquid. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:12722-12730. [PMID: 22877559 DOI: 10.1021/la302231w] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Micellar solutions of hexadecyltrimethylammonium bromide (CTAB) in a protic ionic liquid, ethylammonium nitrate (EAN), are studied by shear rheology, polarizing optical microscopy (POM), conductivity measurements, and small angle neutron scattering (SANS). Three concentration regimes are examined: A dilute regime (with concentrations [CTAB] < 5 wt %) consisting of noninteracting spherical micelles, a semidilute regime (5 wt % ≤ [CTAB] ≤ 45 wt %) where micelles interact via electrostatic repulsions, and a concentrated regime (45 wt % < [CTAB] ≤ 62 wt %) where a reversible, temperature-dependent isotropic (L(1)) to hexatic (Hex) phase transition is observed. The L(1)-Hex transition, which has been predicted but not previously observed, is characterized by (1) a sharp increase in the shear viscosity, (2) the formation of focal conical birefringence textures (observed by POM), and (3) enhancement of the crystalline order, evidenced by the appearance of Bragg reflections in the SANS profiles. Ionic conductivity is not sensitive to the L(1)-Hex transition, which corroborates the absence of topological transitions.
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