1
|
Lifshiz-Simon S, Kunz W, Zemb T, Talmon Y. Ion effects on co-existing pseudo-phases in aqueous surfactant solutions: cryo-TEM, rheometry, and quantification. J Colloid Interface Sci 2024; 660:177-191. [PMID: 38241866 DOI: 10.1016/j.jcis.2024.01.044] [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: 08/17/2023] [Revised: 12/31/2023] [Accepted: 01/06/2024] [Indexed: 01/21/2024]
Abstract
HYPOTHESIS Specific alkaline cation effects control the area per headgroup of alkylester sulphates, which modifies the spontaneous packing of the surfactants. The resulting effective packing minimizes the total bending energy frustration and results in a Boltzmann distribution of coexisting pseudo-phases. These pseudo-phases constitute of micelles and other structures of complex morphology: cylindrical sections, end-caps, branching points, and bilayers, all in dynamic equilibrium. According to our model, excess of end-caps or excess of branching points lead to low viscosity, whereas comparable amounts of both structures lead to viscosity maxima. Relative occurrence of branching points and end-caps is the molecular mechanism at the origin of the salt-sensitive viscosity peak in the "salt-curve" (viscosity against salt concentration at fixed surfactant concentration). Up to now, and as indicated in former papers, this has been a pure model without microscopic verification. EXPERIMENTS In this work, we introduce explicit counting of the number of coexisting pseudo-phases as observed by state-of-the-art cryogenic transmission electron microscopy (cryo-TEM). The model system used, i.e., sodium laurylethersulfate (SLES)/salt/water, is very common as part of cosmetic formulations. As added salts, we used Li+, Na+, K+, and Cs+ chlorides. In parallel to imaging, we measured the macroscopic viscosities of the different solutions. FINDINGS With cryogenic transmission electron microscopy (cryo-TEM), we imaged a variety of morphologies (pseudo-phases) in the different aqueous surfactant/salt solutions: cylindrical micelles with end-caps, discs surrounded by "rims", entangled thread-like micelles with branching points, networks with gliding branching points, and bilayers. The relative chemical potentials of these morphologies could be approximated simply by counting the relative proportion of their occurrence. This simple multi-scale approach avoids any ad-hoc "specificity" assumption of ions, and is based on the bending energy model in an extended version of the Benedek "ladder model". It is capable of explaining and even quantifying the location of all viscosity peaks in the "salt-curves" for the different cations investigated, thus confirming the previously proposed model experimentally, and - thanks to cryo-TEM - for the first time on a microscopic scale. Moreover, this approach can also be applied when the added cations lead to newly observed pseudo-phases, such as discs and vesicles. To the best of our knowledge, this is the first time that cryo-TEM is used, together with a mesoscopic model, to describe a macroscopic property such as viscosity and specific ion effects on it, without any a priori assumption about these effects. So, in total, we could a) confirm the predictions of the previously developed model, b) use cryo-TEM imaging and viscosity measurements to predict and find unusual morphologies when varying the cations of the added salt, and c) count the pseudo-phases in cryo-TEM micrographs to quantitatively explain the different nanostructures.
Collapse
Affiliation(s)
- Sapir Lifshiz-Simon
- Department of Chemical Engineering and the Russell Berrie Nanotechnology Institute (RBNI), Technion - Israel Institute of Technology, Haifa 3200003, Israel
| | - Werner Kunz
- Institute of Physical and Theoretical Chemistry, University of Regensburg, Regensburg 93040, Germany
| | - Thomas Zemb
- Institute for Separation Chemistry ICSM, CEA, CNRS, University of Montpellier, ENSCM, Marcoule 30207, France
| | - Yeshayahu Talmon
- Department of Chemical Engineering and the Russell Berrie Nanotechnology Institute (RBNI), Technion - Israel Institute of Technology, Haifa 3200003, Israel.
| |
Collapse
|
2
|
Schmidt RF, Prévost S, Gradzielski M, Zemb T. Structure of microemulsions in the continuous phase channel. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2023; 46:76. [PMID: 37668863 PMCID: PMC10480248 DOI: 10.1140/epje/s10189-023-00337-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 08/24/2023] [Indexed: 09/06/2023]
Abstract
We have studied the microemulsion and lamellar phases of two of the most commonly described systems based on nonionic C12E5 and ionic AOT surfactants. We show that C12E5 is best described by the symmetric disordered open connected lamellar model (DOC-lamellar), contrary to the more commonly employed standard flexible model. In the case of AOT, the bicontinuous microemulsion structure is best described by the standard flexible model at high temperatures. Around room temperature, connected cylinders in a molten cubic crystal phase are the only description which corresponds to the data. In the lamellar phase, around one third of the available surface area is lost in fluctuations and defects. Comparing structurally predictive models with results from conductivity measurements show that salt adsorption in the hydrated ethoxy groups is dominant for C12E5 (nonionic). For AOT, our conductivity measurements clarify the role of tortuosity versus cation absorption.
Collapse
Affiliation(s)
- Robert Franz Schmidt
- Stranski-Laboratorium Für Physikalische Und Theoretische Chemie, Institut Für Chemie, Technische Universität Berlin, Straße Des 17. Juni 124, 10623, Berlin, Germany.
| | - Sylvain Prévost
- Institut Laue-Langevin, 71 Avenue Des Martyrs CS 20156, 38042, Grenoble Cedex 9, France
| | - Michael Gradzielski
- Stranski-Laboratorium Für Physikalische Und Theoretische Chemie, Institut Für Chemie, Technische Universität Berlin, Straße Des 17. Juni 124, 10623, Berlin, Germany
| | - Thomas Zemb
- UMR 5257 - CEA/CNRS/UM/ENSCM, Institut de Chimie Séparative de Marcoule, ICSM, 30207, Marcoule, France.
| |
Collapse
|
3
|
Salager JL, Marquez R, Rondón M, Bullón J, Graciaa A. Review on Some Confusion Produced by the Bicontinuous Microemulsion Terminology and Its Domains Microcurvature: A Simple Spatiotemporal Model at Optimum Formulation of Surfactant-Oil-Water Systems. ACS OMEGA 2023; 8:9040-9057. [PMID: 36936277 PMCID: PMC10018710 DOI: 10.1021/acsomega.3c00547] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 02/21/2023] [Indexed: 06/01/2023]
Abstract
Fundamental studies have improved understanding of molecular-level properties and behavior in surfactant-oil-water (SOW) systems at equilibrium and under nonequilibrium conditions. However, confusion persists regarding the terms "microemulsion" and "curvature" in these systems. Microemulsion refers to a single-phase system that does not contain distinct oil or water droplets but at least four different structures with globular domains of nanometer size and sometimes arbitrary shape. The significance of "curvature" in such systems is unclear. At high surfactant concentrations (typically 30 wt % or more), a single phase zone has been identified in which complex molecular arrangements may result in light scattering. As surfactant concentration decreases, the single phase is referred to as a bicontinuous microemulsion, known as the middle phase in a Winsor III triphasic system. Its structure has been described as involving simple or multiple surfactant films surrounding more or less elongated excess oil and water phase globules. In cases where the system separates into two or three phases, known as Winsor I or II systems, one of the phases, containing most of the surfactant, is also confusedly referred to as the microemulsion. In this surfactant-rich phase, the only curved objects are micellar size structures that are soluble in the system and have no real interface but rather exchange surfactant molecules with the external liquid phase at an ultrafast pace. The use of the term "curvature" in the context of these complex microemulsion systems is confusing, particularly when applied to merged nanometer-size globular or percolating domains. In this work, we discuss the terms "microemulsion" and "curvature", and the most simple four-dimensional spatiotemporal model is proposed concerning SOW equilibrated systems near the optimum formulation. This model explains the motion of surfactant molecules due to Brownian movement, which is a quick and arbitrary thermal fluctuation, and limited to a short distance. The resulting observation and behavior will be an average in time and in space, leading to a permanent change in the local microcurvature of the aggregate, thus changing the average from micelle-like to inverse micelle-like order over an extremely short time. The term "microcurvature" is used to explain the small variations of globule size and indicates a close-to-zero mean curvature of the surfactant-containing film surface shape.
Collapse
Affiliation(s)
| | - Ronald Marquez
- Laboratorio
FIRP, Universidad de Los Andes, Mérida 5101, Venezuela
| | - Miguel Rondón
- Universidad
Industrial de Santander, Bucaramanga 680002, Colombia
- ICP
Ecopetrol, Piedecuesta 681011, Colombia
| | - Johnny Bullón
- Laboratorio
FIRP, Universidad de Los Andes, Mérida 5101, Venezuela
| | - Alain Graciaa
- Université
de Pau et Pays de l’Adour, UMR 5150 TOTAL-CNRS-UPPA, BP 1155, Pau 64013 Cedex, France
| |
Collapse
|
4
|
Saboorian-Jooybari H, Chen Z. New charged aggregate mathematical models to predict the behavior, structural parameters, and geometrical features of microemulsions. Colloids Surf A Physicochem Eng Asp 2023. [DOI: 10.1016/j.colsurfa.2023.131290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
|
5
|
Tchakalova V, Zemb T, Testard F. Swollen cubic phases with reduced hardness solubilizing a model fragrance oil as a co-surfactant. J Chem Phys 2022; 157:214901. [PMID: 36511558 DOI: 10.1063/5.0124021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Swollen cubic lyotropic ternary phases with Pn3m symmetry and reduced hardness were obtained from a specific binary mixture of cubic phase-forming (phytantriol) and lamellar phase-forming (decaglycerol monooleate) compounds. The microstructures were determined by using a small-angle x-ray scattering technique. The softness and temperature-induced phase transitions were investigated by means of rheology. The incorporation of a surface-active fragrance compound (linalool) at concentrations up to 6 wt. % induced a structural transition toward a softer Im3m bulk cubic phase with longer water channels. Higher linalool concentrations allowed for the spontaneous dispersion of the bulk cubic phase into microscopic particles with a cubic structure (cubosomes).
Collapse
Affiliation(s)
- Vera Tchakalova
- Firmenich SA, R&D Division, Rue de la Bergère 7, CH-1242 Satigny, Switzerland
| | - Thomas Zemb
- Institut de Chimie Séparative, UMR 5257 CEA/CNRS/UM, Centre de Marcoule, F30207 Bagnols sur Ceze, France
| | - Fabienne Testard
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette Cedex, France
| |
Collapse
|
6
|
Chen B, Shi C, Xiong S, Wu K, Yang Y, Mu W, Li X, Yang Y, Shen X, Peng S. Insights into the spontaneous multi-scale supramolecular assembly in an ionic liquid-based extraction system. Phys Chem Chem Phys 2022; 24:25950-25961. [PMID: 36263674 DOI: 10.1039/d2cp03389e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Herein, we report a four-step mechanism for the spontaneous multi-scale supramolecular assembly (MSSA) process in a two-phase system concerning an ionic liquid (IL). The complex ions, elementary building blocks (EBBs), [EBB]n clusters and macroscopic assembly (MA) sphere are formed step by step. The porous large-sized [EBB]n clusters in the glassy state can hardly stay in the IL phase and they transfer to the IL-water interface due to both electroneutrality and amphiphilicity. Then, the clusters undergo random collision in the interface driven by the Marangoni effect and capillary force thereafter. Finally, a single MA sphere can be formed owing to supramolecular interactions. To our knowledge, this is the first example realizing spontaneous whole-process supramolecular assembly covering microscopic, mesoscopic and macroscopic scales in extraction systems. The concept of multi-scale selectivity (MSS) is therefore suggested and its mechanism is revealed. The selective separation and solidification of metal ions can be realized in a MSSA-based extraction system depending on MSS. In addition, insights into the physicochemical characteristics of ILs from microscopic, mesoscopic to macroscopic scales are provided, and especially, the solvation effect of ILs on the large-sized clusters leading to the phase-splitting is examined. It is quite important that the polarization of uranyl in its complex, the growing of uranyl clusters in an IL as well as the glassy material of uranyl are investigated systematically on the basis of both experiment and theoretical calculations in this work.
Collapse
Affiliation(s)
- Baihua Chen
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, P. R. China.
| | - Ce Shi
- Beijing National Laboratory for Molecular Sciences (BNLMS), Fundamental Science on Radiochemistry and Radiation Chemistry Laboratory, Center for Applied Physics and Technology, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
| | - Shijie Xiong
- Beijing National Laboratory for Molecular Sciences (BNLMS), Fundamental Science on Radiochemistry and Radiation Chemistry Laboratory, Center for Applied Physics and Technology, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
| | - Kaige Wu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Fundamental Science on Radiochemistry and Radiation Chemistry Laboratory, Center for Applied Physics and Technology, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
| | - Yanqiu Yang
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, P. R. China.
| | - Wanjun Mu
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, P. R. China.
| | - Xingliang Li
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, P. R. China.
| | - Yuchuan Yang
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, P. R. China.
| | - Xinghai Shen
- Beijing National Laboratory for Molecular Sciences (BNLMS), Fundamental Science on Radiochemistry and Radiation Chemistry Laboratory, Center for Applied Physics and Technology, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
| | - Shuming Peng
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621999, P. R. China.
| |
Collapse
|
7
|
Danino D, Zembc T. On the shape and connections of micelles: EM imaging inspiring thermodynamic modelling. Curr Opin Colloid Interface Sci 2022. [DOI: 10.1016/j.cocis.2022.101607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
8
|
Stemplinger S, Causse J, Prévost S, Pellet-Rostaing S, Zemb T, Horinek D. Short-chain branched sulfosuccinate as a missing link between surfactants and hydrotropes. Phys Chem Chem Phys 2022; 24:11353-11361. [PMID: 35485971 DOI: 10.1039/d1cp04849j] [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
Surfactants aggregate in water into micelles, and these micelles incorporate organic substances to solubilize them. Hydrotropes are compounds that increase the solubility of hydrophobic substances in water without this form of aggregation. Decreasing the chain length of the classical surfactant Aerosol OT (AOT) from C8 to C5 results in a molecule with intermediate properties. Molecular dynamics simulations and surface tension measurements are performed on this short chain derivative of AOT. This compound shows high solubility and at the same time progressive weak aggregation. The hydration of head groups hinders significant plunging into a hydrophobic core, which leads to well defined liquid chain nanodomains. The transition to bicontinuous aggregates is in the concentration range of 1 mol L-1. The sulfonate group of the head groups (placed at the water interface of worm-like aggregates) rather than the aggregate-aggregate interaction is responsible for the unusual small angle X-ray scattering pattern.
Collapse
Affiliation(s)
- Simon Stemplinger
- ICSM, CEA, CNRS, Univ Montpellier, ENSCM, Marcoule, France.,Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Regensburg, Germany.
| | - Jérémy Causse
- ICSM, CEA, CNRS, Univ Montpellier, ENSCM, Marcoule, France
| | | | | | - Thomas Zemb
- ICSM, CEA, CNRS, Univ Montpellier, ENSCM, Marcoule, France
| | - Dominik Horinek
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Regensburg, Germany.
| |
Collapse
|
9
|
Lu Z, Dourdain S, Demé B, Dufrêche JF, Zemb T, Pellet-Rostaing S. Effect of alkyl chain configuration of tertiary amines on uranium extraction and phase stability – Part I: Evaluation of phase stability, extraction, and aggregation properties. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
10
|
Stemplinger S, Duvail M, Dufrêche JF. Molecular dynamics simulations of Eu(NO3)3 salt with DMDOHEMA in n-alkanes: Unravelling curvature properties in liquid-liquid extraction. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118035] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|
11
|
Dhaval M, Vaghela P, Patel K, Sojitra K, Patel M, Patel S, Dudhat K, Shah S, Manek R, Parmar R. Lipid-based emulsion drug delivery systems - a comprehensive review. Drug Deliv Transl Res 2021; 12:1616-1639. [PMID: 34609731 DOI: 10.1007/s13346-021-01071-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2021] [Indexed: 11/26/2022]
Abstract
Lipid-based emulsion system - a subcategory of emulsion technology, has emerged as an enticing option to improve the solubility of the steadily rising water-insoluble candidates. Along with enhancing solubility, additional advantages such as improvement in permeability, protection against pre-systemic metabolism, ease of manufacturing, and easy to scale-up have made lipid-based emulsion technology very popular among academicians and manufacturers. The present article provides a comprehensive review regarding various critical properties of lipid-based emulsion systems, such as microemulsion, nanoemulsion, SMEDDS (self microemulsifying drug delivery system), and SNEDDS (self nanoemulsifying drug delivery system). The present article also explains in detail the similarities and differences between them, the stabilization mechanism, methods of preparation, excipients used to prepare them, and evaluation techniques. Subtle differences between nearly related terminologies such as microemulsion and nanoemulsion, SMEDDS, and SNEDDS are also explained in detail to clarify the basic differences. The present article also gives in-depth information regarding the chemical structure of various lipidic excipients, various possible chemical modifications to modify their inherent properties, and their regulatory status for rational selection.
Collapse
Affiliation(s)
- Mori Dhaval
- B.K. Mody Government Pharmacy College, Polytechnic Campus, Near Ajidam, Rajkot, Gujarat, India.
| | - Poonam Vaghela
- B.K. Mody Government Pharmacy College, Polytechnic Campus, Near Ajidam, Rajkot, Gujarat, India
| | - Kajal Patel
- B.K. Mody Government Pharmacy College, Polytechnic Campus, Near Ajidam, Rajkot, Gujarat, India
| | - Keshvi Sojitra
- B.K. Mody Government Pharmacy College, Polytechnic Campus, Near Ajidam, Rajkot, Gujarat, India
| | - Mohini Patel
- B.K. Mody Government Pharmacy College, Polytechnic Campus, Near Ajidam, Rajkot, Gujarat, India
| | - Sushma Patel
- B.K. Mody Government Pharmacy College, Polytechnic Campus, Near Ajidam, Rajkot, Gujarat, India
| | - Kiran Dudhat
- K. V. Virani Institute of Pharmacy and Research Centre, Badhada, Gujarat, India
| | - Sunny Shah
- B.K. Mody Government Pharmacy College, Polytechnic Campus, Near Ajidam, Rajkot, Gujarat, India
| | - Ravi Manek
- B.K. Mody Government Pharmacy College, Polytechnic Campus, Near Ajidam, Rajkot, Gujarat, India
| | - Ramesh Parmar
- B.K. Mody Government Pharmacy College, Polytechnic Campus, Near Ajidam, Rajkot, Gujarat, India
| |
Collapse
|
12
|
Špadina M, Dufrêche JF, Pellet-Rostaing S, Marčelja S, Zemb T. Molecular Forces in Liquid-Liquid Extraction. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:10637-10656. [PMID: 34251218 DOI: 10.1021/acs.langmuir.1c00673] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The phase transfer of ions is driven by gradients of chemical potentials rather than concentrations alone (i.e., by both the molecular forces and entropy). Extraction is a combination of high-energy interactions that correspond to short-range forces in the first solvation shell such as ion pairing or complexation forces, with supramolecular and nanoscale organization. While the latter are similar to the long-range solvent-averaged interactions in the colloidal world, in solvent extraction they are associated with lower characteristic lengths of the nanometric domain. Modeling of such complex systems is especially complicated because the two domains are coupled, whereas the resulting free energy of extraction is around kBT to guarantee the reversibility of the practical process. Nevertheless, quantification is possible by considering a partitioning of space among the polar cores, interfacial film, and solvent. The resulting free energy of transfer can be rationalized by utilizing a combination of terms which represent strong complexation energies, counterbalanced by various entropic effects and the confinement of polar solutes in nanodomains dispersed in the diluent, together with interfacial extractant terms. We describe here this ienaics approach in the context of solvent extraction systems; it can also be applied to further complex ionic systems, such as membranes and biological interfaces.
Collapse
Affiliation(s)
- Mario Špadina
- Group for Computational Life Sciences, Rud̵er Bošković Institute, Division of Physical Chemistry, 10000 Zagreb, Croatia
- Faculty of Health Sciences, University of Ljubljana, 1000 Ljubljana, Slovenia
| | | | | | - Stjepan Marčelja
- Research School of Physics, The Australian National University, Canberra, Australia
| | - Thomas Zemb
- ICSM, CEA, CNRS, ENSCM, Université Montpellier, Marcoule, France
| |
Collapse
|
13
|
Gourdin-Bertin S, Dufrêche JF, Duvail M, Zemb T. Microemulsion as Model to Predict Free Energy of Transfer of Electrolyte in Solvent Extraction. SOLVENT EXTRACTION AND ION EXCHANGE 2021. [DOI: 10.1080/07366299.2021.1953259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
| | | | - Magali Duvail
- ICSM, CEA, Univ Montpellier, CNRS, ENSCM, Marcoule, France
| | - Thomas Zemb
- ICSM, CEA, Univ Montpellier, CNRS, ENSCM, Marcoule, France
| |
Collapse
|
14
|
Banerjee A, Liu Y. Essential Factor of Perfluoroalkyl Surfactants Contributing to Efficacy in Firefighting Foams. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:8937-8944. [PMID: 34297583 DOI: 10.1021/acs.langmuir.1c00463] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Two simple model aqueous foams, one made from a perfluoroalkyl surfactant and one from a silicone polyether surfactant, are compared with regard to their stability in contact with heptane as a model fuel oil. The observed foam stabilities are explained in terms of the equilibrium phase behavior of the system water-surfactant-heptane. It is demonstrated that the fundamental enabling factor that makes perfluoroalkyl surfactant perform exceedingly well in stabilizing foams on hydrocarbon fuel oil is its oleophobicity. For hydrocarbon or silicone surfactants, the propensity for the surfactant phase to solubilize hydrocarbon oil and be solubilized in the oil destabilizes the foam. This is particularly so if the surfactant's phase inversion by temperature (PIT) range falls within the application temperature range.
Collapse
Affiliation(s)
- Anirudha Banerjee
- Performance Silicones Research and Development, The Dow Chemical Company, 2200 West Salzburg Road, Auburn, Michigan 48611, United States
| | - Yihan Liu
- Performance Silicones Research and Development, The Dow Chemical Company, 2200 West Salzburg Road, Auburn, Michigan 48611, United States
| |
Collapse
|
15
|
Menold P, Strey R, Preisig N, Stubenrauch C. Experimental evidence of a transition from a sponge-like to a foam-like nanostructure in water-rich L 3 phases. J Colloid Interface Sci 2021; 601:133-142. [PMID: 34058549 DOI: 10.1016/j.jcis.2021.05.063] [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: 04/11/2021] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 10/21/2022]
Abstract
HYPOTHESIS The micrometer-sized gas bubbles of a liquid foam with a dispersed gas phase of > 74 vol% are polyhedral and surrounded by a continuous aqueous phase. The structure of a water-rich microemulsion with a water phase of > 74 vol% normally consists of oil droplets in water or is bicontinuous. We hypothesize that at these high water contents polyhedral water droplets in oil can also exist. EXPERIMENTS We (a) carried out phase studies on the water-rich side of the phase diagram of the quaternary system water/NaCl - hexyl methacrylate - AOT, because AOT is known for its propensity to form water-in-oil structures and hexyl methacrylate can be polymerized, (b) measured the electrical conductivities and viscosities, and (c) visualized the nanostructure with freeze-fracture electron microscopy (FFEM). FINDINGS We found narrow 1-phase regions emanating from the L3 phase of the oil-free water/NaCl - AOT system by adding small amounts of oil. In these regions the conductivities become extremely low and the viscosities are extremely high. In addition, FFEM images clearly show the foam-like nanostructure.
Collapse
Affiliation(s)
- Philipp Menold
- Institute of Physical Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Reinhard Strey
- Institute of Physical Chemistry, University of Cologne, Luxemburger Straße 116, 50939 Cologne, Germany
| | - Natalie Preisig
- Institute of Physical Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Cosima Stubenrauch
- Institute of Physical Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany.
| |
Collapse
|
16
|
Gradzielski M, Duvail M, de Molina PM, Simon M, Talmon Y, Zemb T. Using Microemulsions: Formulation Based on Knowledge of Their Mesostructure. Chem Rev 2021; 121:5671-5740. [PMID: 33955731 DOI: 10.1021/acs.chemrev.0c00812] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Microemulsions, as thermodynamically stable mixtures of oil, water, and surfactant, are known and have been studied for more than 70 years. However, even today there are still quite a number of unclear aspects, and more recent research work has modified and extended our picture. This review gives a short overview of how the understanding of microemulsions has developed, the current view on their properties and structural features, and in particular, how they are related to applications. We also discuss more recent developments regarding nonclassical microemulsions such as surfactant-free (ultraflexible) microemulsions or ones containing uncommon solvents or amphiphiles (like antagonistic salts). These new findings challenge to some extent our previous understanding of microemulsions, which therefore has to be extended to look at the different types of microemulsions in a unified way. In particular, the flexibility of the amphiphilic film is the key property to classify different microemulsion types and their properties in this review. Such a classification of microemulsions requires a thorough determination of their structural properties, and therefore, the experimental methods to determine microemulsion structure and dynamics are reviewed briefly, with a particular emphasis on recent developments in the field of direct imaging by means of electron microscopy. Based on this classification of microemulsions, we then discuss their applications, where the application demands have to be met by the properties of the microemulsion, which in turn are controlled by the flexibility of their amphiphilic interface. Another frequently important aspect for applications is the control of the rheological properties. Normally, microemulsions are low viscous and therefore enhancing viscosity has to be achieved by either having high concentrations (often not wished for) or additives, which do not significantly interfere with the microemulsion. Accordingly, this review gives a comprehensive account of the properties of microemulsions, including most recent developments and bringing them together from a united viewpoint, with an emphasis on how this affects the way of formulating microemulsions for a given application with desired properties.
Collapse
Affiliation(s)
- Michael Gradzielski
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Technische Universität Berlin, D-10623 Berlin, Germany
| | - Magali Duvail
- ICSM, Université Montpellier, CEA, CNRS, ENSCM, 30207 Marcoule, France
| | - Paula Malo de Molina
- Centro de Física de Materiales (CFM) (CSIC-UPV/EHU)-Materials Physics Center (MPC), Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain.,IKERBASQUE - Basque Foundation for Science, María Díaz de Haro 3, 48013 Bilbao, Spain
| | - Miriam Simon
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Technische Universität Berlin, D-10623 Berlin, Germany.,Department of Chemical Engineering and the Russell Berrie Nanotechnolgy Inst. (RBNI), Technion-Israel Institute of Technology, Haifa, IL-3200003, Israel
| | - Yeshayahu Talmon
- Department of Chemical Engineering and the Russell Berrie Nanotechnolgy Inst. (RBNI), Technion-Israel Institute of Technology, Haifa, IL-3200003, Israel
| | - Thomas Zemb
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Technische Universität Berlin, D-10623 Berlin, Germany.,ICSM, Université Montpellier, CEA, CNRS, ENSCM, 30207 Marcoule, France
| |
Collapse
|
17
|
Koli AR, Ranch KM, Patel HP, Parikh RK, Shah DO, Maulvi FA. Oral bioavailability improvement of felodipine using tailored microemulsion: Surface science, ex vivo and in vivo studies. Int J Pharm 2021; 596:120202. [DOI: 10.1016/j.ijpharm.2021.120202] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 12/26/2020] [Accepted: 12/28/2020] [Indexed: 01/24/2023]
|
18
|
Denk P, El Maangar A, Lal J, Kleber D, Zemb T, Kunz W. Phase diagrams and microstructures of aqueous short alkyl chain polyethylene glycol ether carboxylate and carboxylic acid triblock surfactant solutions. J Colloid Interface Sci 2021; 590:375-386. [PMID: 33556757 DOI: 10.1016/j.jcis.2021.01.061] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 01/19/2021] [Accepted: 01/20/2021] [Indexed: 11/15/2022]
Abstract
HYPOTHESIS The surfactant C8EO8CH2COOH (Akypo LF2) and its salts have a small hydrophobic and a significantly longer hydrophilic part. As a consequence, there must be a significant steric constraint, once these surfactant molecules form micelles. In addition, the partially charged headgroups should bring some additional fine-tuning via electrostatic interactions to this "essentially non-ionic" surfactant. EXPERIMENTS Phase diagrams of binary mixtures of water and C8EO8CH2COOH are established over large concentration and temperature ranges, also at different pHs and in the presence of sodium and calcium ions. Surface tensions and osmotic pressures are measured to understand the systems. To evaluate the microstructures, also Dynamic Light Scattering and Small-Angle X-ray Scattering are performed. FINDINGS Apart from the formation of coacervates at very low surfactant concentrations, spherical micelles persist over the whole concentration and temperature range and do not change in size and shape. At very high surfactant concentrations, above 60% by weight, where the headgroups are no longer fully hydrated, the standard core-shell structure of micelles vanishes and highly stabilized aggregates of 8-26 octyl chains are suspended in interdigitated polyoxyethylene layers and form an "osmotic brush". When the acid is partially transformed to a sodium salt, the repulsion between the micelles increases, whereas bridging between micelles prevails, when the counterions are calcium cations. Remarkably, the negative charges of the headgroups are randomly distributed in the hydrophilic ethylene oxide shell. Altogether, a phase diagram without lyotropic liquid crystalline phases and an extreme shift of the cloud-point in temperature and composition is found, similar to the phase diagram of C8EO8OH already known in literature. The phase properties can be explained by the curvature and packing constraints together with the Lindemann rule applied to short hydrocarbon chains.
Collapse
Affiliation(s)
- Patrick Denk
- Institute of Physical and Theoretical Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
| | | | - Jyotsana Lal
- Institute of Physical and Theoretical Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, D-93040 Regensburg, Germany; Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, USA; Department of Physics, Northern Illinois University, DeKalb, IL 60115, USA
| | - David Kleber
- Institute of Physical and Theoretical Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, D-93040 Regensburg, Germany
| | - Thomas Zemb
- ICSM, Univ. Montpellier, CEA, CNRS, ENSCM, Marcoule, France
| | - Werner Kunz
- Institute of Physical and Theoretical Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, D-93040 Regensburg, Germany.
| |
Collapse
|
19
|
Vatin M, Duvail M, Guilbaud P, Dufrêche JF. Liquid/liquid interface in periodic boundary condition. Phys Chem Chem Phys 2021; 23:1178-1187. [PMID: 33355331 DOI: 10.1039/d0cp04629a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We study how surface phenomena can change the interface geometry in liquid-liquid two-phase systems with periodic boundary conditions. Without any curvature effect on surface tension, planar (slab), cylindrical, and spherical structures are successively obtained as a function of the total composition and elongation of the box, in accordance with molecular dynamics simulations for a water/heptane system. The curvature effects described by Tolman relationship desymmetrize the phase diagram by stabilizing a concavity but it leads to inconsistencies with high curvature. Helfrich model partially resolves this and predicts the possible presence of shells reflecting a frustrated system.
Collapse
Affiliation(s)
- Marin Vatin
- ICSM, CEA, Univ Montpellier, CNRS, ENSCM, Marcoule, France.
| | - Magali Duvail
- ICSM, CEA, Univ Montpellier, CNRS, ENSCM, Marcoule, France.
| | | | | |
Collapse
|