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Salvati Manni L, Wood K, Klapproth A, Warr GG. Inelastic neutron scattering and spectroscopy methods to characterize dynamics in colloidal and soft matter systems. Adv Colloid Interface Sci 2024; 326:103135. [PMID: 38520888 DOI: 10.1016/j.cis.2024.103135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 03/25/2024]
Abstract
Colloidal systems and soft materials are well suited to neutron scattering, and the community has readily adopted elastic scattering techniques to investigate their structure. Due to their unique properties, neutrons may also be used to characterize the dynamics of soft materials over a wide range of length and time scales in situ. Both static structures and an understanding of how molecules move about their equilibrium positions is essential if we are to deliver on the promise of rationally designing soft materials. In this review we introduce the basics of neutron spectroscopy and explore the ways in which inelastic neutron scattering can be used to study colloidal and soft materials. Illustrative examples are chosen that highlight the phenomena suitable for investigation using this suite of techniques.
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Affiliation(s)
- Livia Salvati Manni
- School of Chemistry, University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia; School of Chemistry, Monash University, Wellington Road, Clayton, VIC 3800, Australia; School of Environmental and Life Sciences, University of Newcastle, Callaghan 2308, NSW, Australia; Australian Synchrotron, ANSTO, 800 Blackburn Rd, Clayton, VIC 3168, Australia
| | - Kathleen Wood
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Alice Klapproth
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Gregory G Warr
- School of Chemistry, University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia.
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2
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Rahman A, Eastoe J. The effects of surfactant and oil chemical structures on self-assembly in apolar media. SOFT MATTER 2022; 18:9133-9152. [PMID: 36444561 DOI: 10.1039/d2sm00827k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The thermodynamic and chemical structural aspects of surfactant self-assembly in aqueous systems have been much studied. On the other hand, for oil-water interfaces the effects of chemical structures of surfactants and solvents have received less attention. This review focuses on the surfactant chemical effects in low dielectric solvents, in particular formation and properties of surfactant films at oil-water interfaces. For this purpose, reversed micelles (RMs) and water-in-oil (W/O) microemulsions (μEs) serve as model systems, since electrostatic effects are minimized, allowing a focus on chain architecture of the surfactants and oil solvents themselves. It is noted that chemical structure can have profound effects on stability and self-assembly, suggesting a possibility of identifying unified chemical principles for designing and formulating systems across various thermodynamic conditions.
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Affiliation(s)
- Adhip Rahman
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK.
| | - Julian Eastoe
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK.
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3
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Murakami H. Persistent optical hole-burning spectroscopy of nano-confined dye molecules in liquid at room temperature: Spectral narrowing due to a glassy state and extraordinary relaxation in a nano-cage. J Chem Phys 2018; 148:144505. [PMID: 29655335 DOI: 10.1063/1.5008448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Persistent optical hole-burning spectroscopy has been conducted for a dye molecule within a very small (∼1 nm) reverse micelle at room temperature. The spectra show a spectral narrowing due to site-selective excitation. This definitely demonstrates that the surroundings of the dye molecule are in a glassy state regardless of a solution at room temperature. On the other hand, the hole-burning spectra exhibit large shifts from excitation frequencies, and their positions are almost independent of excitation frequencies. The hole-burning spectra have been theoretically calculated by taking account of a vibronic absorption band of the dye molecule under the assumption that the surroundings of the dye molecule are in a glassy state. The calculated results agree with the experimental ones that were obtained for the dye molecule in a polymer glass for comparison, where it has been found that the ratio of hole-burning efficiencies of vibronic- to electronic-band excitations is quite high. On the other hand, the theoretical results do not explain the large spectral shift from the excitation frequency and small spectral narrowing observed in the hole-burning spectra measured for the dye-containing reverse micelle. It is thought that the spectral shift and broadening occur within the measurement time owing to the relaxation process of the surroundings that are hot with the thermal energy deposited by the dye molecule optically excited. Furthermore, the relaxation should be temporary because the cooling of the inside of the reverse micelle takes place with the dissipation of the excess thermal energy to the outer oil solvent, and so the surroundings of the dye molecule return to the glassy state and do not attain the thermal equilibrium. These results suggest that a very small reverse micelle provides a unique reaction field in which the diffusional motion can be controlled by light in a glassy state.
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Affiliation(s)
- Hiroshi Murakami
- QST Advanced Study Laboratory and Kansai Photon Science Institute, National Institutes for Quantum and Radiological Science and Technology (QST), Kizugawa City, Kyoto 619-0215, Japan
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Kuttich B, Matt A, Weber A, Grefe AK, Vietze L, Stühn B. Water/PEG Mixtures: Phase Behavior, Dynamics and Soft Confinement. ACTA ACUST UNITED AC 2017. [DOI: 10.1515/zpch-2017-1018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Polyethylene glycol is water soluble and forms an eutectic system with water. The eutectic temperature is −19 °C for M=1500 g mol−1 and increases with molecular weight. The dielectric relaxation spectrum of the mixtures exhibits a strong loss maximum in ϵ″ (ω) similar to pure water. Relaxation time increases with the addition of PEG. Activation energies exhibit a maximum of 0.35 eV at molar fraction χp
≈0.2. This compares well with results on ethanol water mixtures. Adding PEG molecules to nanoscopic water droplets of inverse microemulsions has only small impact on the bending modulus κ of a non-ionic microemulsion. In AOT based microemulsions an increase or decrease of κ is found in dependence on the size of the droplets. This is in accordance with the variation of the dynamic percolation transition in the same systems.
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Affiliation(s)
- Björn Kuttich
- Condensed Matter Physics , Darmstadt Technical University , Darmstadt , Germany
| | - Alexander Matt
- Condensed Matter Physics , Darmstadt Technical University , Darmstadt , Germany
| | - Andreas Weber
- Condensed Matter Physics , Darmstadt Technical University , Darmstadt , Germany
| | - Ann-Kathrin Grefe
- Condensed Matter Physics , Darmstadt Technical University , Darmstadt , Germany
| | - Laura Vietze
- Condensed Matter Physics , Darmstadt Technical University , Darmstadt , Germany
| | - Bernd Stühn
- Condensed Matter Physics , Darmstadt Technical University , Darmstadt , Germany
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Oberdisse J, Hellweg T. Structure, interfacial film properties, and thermal fluctuations of microemulsions as seen by scattering experiments. Adv Colloid Interface Sci 2017; 247:354-362. [PMID: 28751064 DOI: 10.1016/j.cis.2017.07.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 07/12/2017] [Accepted: 07/12/2017] [Indexed: 10/19/2022]
Abstract
The physics of microemulsions and in particular Dominique Langevin's contributions to the understanding of microemulsion structure and bending properties using scattering techniques are reviewed. Among the many methods used by her and her co-workers, we particularly emphasize optical techniques and small angle neutron scattering (SANS), but also neutron spin echo spectroscopy (NSE). The review is then extended to more recent studies of properties of microemulsions close to surfaces, using reflectometry and grazing-incidence small angle neutron scattering (GISANS).
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Kittaka S, Yoshida K, Yamaguchi T, Bellissent Funel MC, Fouquet P. A neutron spin echo study of low-temperature water confined in the spherical silica pores of SBA-16. Phys Chem Chem Phys 2017; 19:10502-10510. [DOI: 10.1039/c6cp08047b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dynamic properties of heavy water (D2O) and light water (H2O) confined in porous silica SBA-16 were studied over a temperature range of 210–290 K by neutron spin echo measurements.
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Affiliation(s)
| | | | | | | | - Peter Fouquet
- Institut Laue-Langevin
- 71 Avenue des Martyrs
- CS 20156
- 38042 Grenoble Cedex 9
- France
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7
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Lannert M, Müller A, Gouirand E, Talluto V, Rosenstihl M, Walther T, Stühn B, Blochowicz T, Vogel M. Glycerol in micellar confinement with tunable rigidity. J Chem Phys 2016; 145:234511. [PMID: 28010095 DOI: 10.1063/1.4972009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We investigate the glassy dynamics of glycerol in the confinement of a microemulsion system, which is stable on cooling down to the glass transition of its components. By changing the composition, we vary the viscosity of the matrix, while keeping the confining geometry intact, as is demonstrated by small angle X-ray scattering. By means of 2H NMR, differential scanning calorimetry, and triplet solvation dynamics we, thus, probe the dynamics of glycerol in confinements of varying rigidity. 2H NMR results show that, at higher temperatures, the dynamics of confined glycerol is unchanged compared to bulk behavior, while the reorientation of glycerol molecules becomes significantly faster than in the bulk in the deeply supercooled regime. However, comparison of different 2H NMR findings with data from calorimetry and solvation dynamics reveals that this acceleration is not due to the changed structural relaxation of glycerol, but rather due to the rotational motion of essentially rigid glycerol droplets or of aggregates of such droplets in a more fluid matrix. Thus, independent of the matrix mobility, the glycerol dynamics remains unchanged except for the smallest droplets, where an increase of Tg and, thus, a slowdown of the structural relaxation is observed even in a fluid matrix.
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Affiliation(s)
- Michael Lannert
- TU Darmstadt, Institut für Festkörperphysik, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Allyn Müller
- TU Darmstadt, Institut für Festkörperphysik, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Emmanuel Gouirand
- TU Darmstadt, Institut für Festkörperphysik, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Vincenzo Talluto
- TU Darmstadt, Institut für Festkörperphysik, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Markus Rosenstihl
- TU Darmstadt, Institut für Festkörperphysik, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Thomas Walther
- TU Darmstadt, Institut für Festkörperphysik, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Bernd Stühn
- TU Darmstadt, Institut für Festkörperphysik, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Thomas Blochowicz
- TU Darmstadt, Institut für Festkörperphysik, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - Michael Vogel
- TU Darmstadt, Institut für Festkörperphysik, Hochschulstraße 6, 64289 Darmstadt, Germany
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Kuttich B, Grefe AK, Stühn B. Changes in the bending modulus of AOT based microemulsions induced by the incorporation of polymers in the water core. SOFT MATTER 2016; 12:6400-6411. [PMID: 27416768 DOI: 10.1039/c6sm01253a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The bending modulus κ is known to be a crucial parameter for the stability of the droplet phase in microemulsion systems. For AOT based water in oil microemulsions the bending modulus of the surfactant has values close to kBT but can be influenced by the presence of polymers. In this work we focus on the water soluble polymer polyethylene glycol and how it influences the bending modulus. An increase by a factor of three is found. For the correct evaluation of the bending modulus via percolation temperatures and droplet radii, thus by dielectric spectroscopy and small angle X-ray scattering, the determination of the radii right at the percolation temperature is crucial as we will show, although it is often neglected. In order to precisely determine the droplet radii we will present a global fitting model which provides reliable results with a minimum number of free fitting parameters.
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Affiliation(s)
- Björn Kuttich
- Experimental Condensed Matter Physics, TU Darmstadt, Germany.
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10
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Zinn T, Willner L, Lund R. Nanoscopic confinement through self-assembly: crystallization within micellar cores exhibits simple Gibbs-Thomson behavior. PHYSICAL REVIEW LETTERS 2014; 113:238305. [PMID: 25526170 DOI: 10.1103/physrevlett.113.238305] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Indexed: 06/04/2023]
Abstract
It is well known that liquids confined to small nanoscopic pores and droplets exhibit thermal behavior very different from bulk samples. Less is known about liquids spontaneously confined through self-assembly into micellar structures. Here we demonstrate, using a very well-defined n-alkyl-poly(ethylene oxide) polymer system with a tunable structure, that n-alkane(s) forming 2-3 nm small micellar cores are affected considerably by confinement in the form of melting point depressions. Moreover, comparing the reduction in melting points, ΔT_{m}, determined through volumetric and calorimetric methods with the micellar core radius, R_{c}, obtained from small-angle x-ray scattering, we find excellent agreement with the well-known Gibbs-Thomson equation, ΔT_{m}∼R_{c}^{-1}. This demonstrates that the reduced size, i.e., the Laplace pressure, is the dominant parameter governing the melting point depression in micellar systems.
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Affiliation(s)
- Thomas Zinn
- Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway
| | - Lutz Willner
- Jülich Centre for Neutron Science (JCNS) and Institute for Complex Systems (ICS),Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Reidar Lund
- Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway
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12
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Hoffmann I, de Molina PM, Farago B, Falus P, Herfurth C, Laschewsky A, Gradzielski M. Dynamics of microemulsions bridged with hydrophobically end-capped star polymers studied by neutron spin-echo. J Chem Phys 2014; 140:034902. [DOI: 10.1063/1.4861894] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Soper AK. Radical re-appraisal of water structure in hydrophilic confinement. Chem Phys Lett 2013; 590:1-15. [PMID: 25843963 PMCID: PMC4376068 DOI: 10.1016/j.cplett.2013.10.075] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 10/22/2013] [Indexed: 11/29/2022]
Abstract
The structure of water confined in MCM41 silica cylindrical pores is studied to determine whether confined water is simply a version of the bulk liquid which can be substantially supercooled without crystallisation. A combination of total neutron scattering from the porous silica, both wet and dry, and computer simulation using a realistic model of the scattering substrate is used. The water in the pore is divided into three regions: core, interfacial and overlap. The average local densities of water in these simulations are found to be about 20% lower than bulk water density, while the density in the core region is below, but closer to, the bulk density. There is a decrease in both local and core densities when the temperature is lowered from 298 K to 210 K. The radical proposal is made here that water in hydrophilic confinement is under significant tension, around -100 MPa, inside the pore.
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Appel M, Spehr TL, Wipf R, Moers C, Frey H, Stühn B. Micellar interactions in water-AOT based droplet microemulsions containing hydrophilic and amphiphilic polymers. J Chem Phys 2013; 139:184903. [DOI: 10.1063/1.4828741] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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15
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Murakami H, Sada T, Yamada M, Harada M. Nanometer-scale water droplet free from the constraint of reverse micelles at low temperatures. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:052304. [PMID: 24329261 DOI: 10.1103/physreve.88.052304] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 07/02/2013] [Indexed: 06/03/2023]
Abstract
Temperature dependence of the configurational fluctuation of water confined in a reverse micellar solution has been studied by absorption spectroscopy of a probe molecule. We have found that the configurational fluctuation is liquidlike below the homogeneous nucleation temperature. This is proposed to be due to a large reduction in the confinement of water, and is explained in terms of water shedding from the reverse micelle. Further, the configurational fluctuation is frozen at ~210 K. A reverse micellar solution is considered to be a promising candidate for studies of supercooled water.
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Affiliation(s)
- H Murakami
- Kansai Photon Science Institute, Japan Atomic Energy Agency, Kyoto 619-0215, Japan
| | - T Sada
- Kansai Photon Science Institute, Japan Atomic Energy Agency, Kyoto 619-0215, Japan and Faculty of Human Life and Environment, Nara Women's University, Nara 630-8506, Japan
| | - M Yamada
- Kansai Photon Science Institute, Japan Atomic Energy Agency, Kyoto 619-0215, Japan and Faculty of Human Life and Environment, Nara Women's University, Nara 630-8506, Japan
| | - M Harada
- Faculty of Human Life and Environment, Nara Women's University, Nara 630-8506, Japan
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Murakami H. Protein and water confined in nanometer-scale reverse micelles studied by near infrared, terahertz, and ultrafast visible spectroscopies. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2013; 93:183-211. [PMID: 24018326 DOI: 10.1016/b978-0-12-416596-0.00006-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
Abstract
Protein-containing reverse (PCR) micelles are suitable systems to study the properties of proteins and waters in a cell-like environment. A model for determining the structural parameters of PCR micelles, such as the aqueous cavity size and molecule number of water within the reverse micelle, is presented. The model is based on an important hypothesis that the structural parameters of the protein-unfilled reverse micelle do not change after solubilization of protein. I describe a procedure using near infrared spectroscopy of OH stretching vibration band of water to verify the hypothesis. Further, the terahertz (THz) absorption spectrum of myoglobin is derived from THz time-domain spectroscopy of the PCR micellar solution, and the states of waters in reverse micelles with and without protein are discussed on the basis of the structural parameters. The last topic is on internal dynamics of PCR micelles on timescales from femtoseconds to nanoseconds studied by femtosecond time-resolved fluorescence spectroscopy.
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Affiliation(s)
- Hiroshi Murakami
- Kansai Photon Science Institute, Japan Atomic Energy Agency, Kyoto, Japan.
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17
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Bicontinuous microemulsions with extremely high temperature stability based on skin friendly oil and sugar surfactant. Colloids Surf A Physicochem Eng Asp 2013. [DOI: 10.1016/j.colsurfa.2012.10.039] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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19
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Appel M, Spehr TL, Wipf R, Stühn B. Water–AOT–alkylbenzene microemulsions: Influence of alkyl chain length on structure and percolation behavior. J Colloid Interface Sci 2012; 376:140-5. [DOI: 10.1016/j.jcis.2012.02.062] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2012] [Revised: 02/23/2012] [Accepted: 02/25/2012] [Indexed: 10/28/2022]
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Wellert S, Karg M, Holderer O, Richardt A, Hellweg T. Temperature dependence of the surfactant film bending elasticity in a bicontinuous sugar surfactant based microemulsion: a quasielastic scattering study. Phys Chem Chem Phys 2011; 13:3092-9. [DOI: 10.1039/c0cp02044c] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Cametti C. Dielectric spectra of ionic water-in-oil microemulsions below percolation: frequency dependence behavior. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2010; 81:031403. [PMID: 20365732 DOI: 10.1103/physreve.81.031403] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Indexed: 05/29/2023]
Abstract
We have investigated the dielectric properties of water-in-oil microemulsions composed of sodium bis(2-ethyl-hexyl)sulfosuccinate, water, and decane, using radiofrequency impedance spectroscopy, below the percolation threshold, where the system behaves as surfactant-coated individual water droplets dispersed in a continuous oil phase. The analysis of the dielectric spectra has evidenced that the whole dielectric response below percolation is due to two different contributions, which give rise to two partially overlapping dielectric relaxations, approximately in the frequency range from 10 to 500 MHz. The first of these mechanisms is originated by the bulk polarization of counterions distributed in the electrical double layer of the droplet interior. The second mechanism is associated with a correlated motion of the anionic head groups SO3- at the surfactant-water interface. The introduction of this latter contribution allows us to justify the experimentally observed increase in the low-frequency permittivity as a function of temperature up to temperatures very close to percolation. The present study shows that deviations from the expected values on the basis of dielectric theories of heterogeneous systems (Maxwell-Wagner effect) observed when percolation is approaching can be accounted for, in a reasonable way, by the introduction of a further polarization mechanism, which involves the anionic surfactant groups. Only very close to percolation, when microemulsions undergo a scaling behavior, deviations of the permittivity (and electrical conductivity as well) are a print of the structural rearrangement of the whole system and models based on colloidal particle suspension theories fail. Even if the whole picture of the dielectric properties of microemulsion systems does not change in deep, nevertheless, the refinement introduced in this paper demonstrates how different polarization mechanisms could be simultaneously present in these rather complex systems and, above all, how the individual particle colloidal properties are maintained up to very close to the percolation threshold.
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Affiliation(s)
- C Cametti
- Dipartimento di Fisica, Universita di Roma La Sapienza and INFM-CNR CRS-SOFT, Rome, Italy.
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Dynamics in water-AOT-n-decane microemulsions with poly(ethylene glycol) probed by dielectric spectroscopy. Colloid Polym Sci 2010. [DOI: 10.1007/s00396-010-2199-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Watanabe K, Oguni M, Tadokoro M, Kobayashi C. Ordering and Freezing-in Phenomena of Nanochannel Water in Crystalline Organic/Inorganic Self-Assembled Complex [Cr(H2bim)3](TMA)·23.5H2O. J Phys Chem B 2009; 113:14323-8. [DOI: 10.1021/jp907736n] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Keisuke Watanabe
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8551, Japan, and Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Masaharu Oguni
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8551, Japan, and Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Makoto Tadokoro
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8551, Japan, and Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Chiho Kobayashi
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8551, Japan, and Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
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