1
|
Zhang Z, Song Q, Zhao Z, Chang K, Shu P, Wang J, Yan H, Zhang Y. Cosmetically Approved Short-Chain Alcohol/Triethyl Citrate/Water Surfactant-Free Microemulsions and Potential Application to Transdermal Penetration of α-Arbutin. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:11011-11022. [PMID: 38739267 DOI: 10.1021/acs.langmuir.4c00382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2024]
Abstract
Surfactant-free microemulsions (SFMEs) exhibited remarkable advantages and potential, attributed to their similarity to traditional surfactant-based microemulsions and the absence of surfactants. Herein, a novel SFME was developed utilizing cosmetically approved materials, such as short-chain alcohol as an amphi-solvent, triethyl citrate (TEC) as the nonpolar phase, and water as the polar phase. 1,2-Pentanediol (PtDO)/TEC/water combination can form the largest monophasic zone, accounting for ∼74% of the total phase diagram area, due to an optimal hydrophilic (water)-lipophilic (TEC) balance. Comparable to surfactant-based microemulsion, PtDO/TEC/water SFME can also be categorized into three types: water-in-oil, discontinuous, and oil-in-water. As TEC or water is increased, or PtDO is decreased, the nanoaggregates in PtDO/TEC/water SFME grow from <5 nm to tens of nanometers. The addition of α-arbutin (ABN) does not disrupt PtDO/TEC/water SFME, but rather enhances its formation, resulting in a larger monophasic area and consistent size (2.8-3.8 nm) through participating in interface assembly. Furthermore, ABN-loaded PtDO/TEC/water SFME exhibits remarkable resistance to dilution, exceptional stability, and minimal irritation. Notably, PtDO/TEC/water SFME significantly boosts ABN's solubility in water by 2 times, its percutaneous penetration rate by 3-4 times, and enables a slow-release DPPH• radical scavenging effect. This SFME serves as a safe and cosmetically suitable nanoplatform for the delivery of bioactive substances.
Collapse
Affiliation(s)
- Zhiqin Zhang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, JNU-HBN Cosmetic Functional Molecular Innovation Joint Laboratory, School of Chemical & Materials Engineering, Jiangnan University, No. 1800 Lihu Avenue, Wuxi 214122, China
| | - Qingle Song
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, JNU-HBN Cosmetic Functional Molecular Innovation Joint Laboratory, School of Chemical & Materials Engineering, Jiangnan University, No. 1800 Lihu Avenue, Wuxi 214122, China
- HBN Research Institute and Biological Laboratory, Shenzhen Hujia Technology Co., Ltd., Shenzhen 518000, China
| | - Zhen Zhao
- School of Pharmaceutical Sciences, Liaocheng University, Liaocheng, Shandong 252059, China
| | - Kuan Chang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, JNU-HBN Cosmetic Functional Molecular Innovation Joint Laboratory, School of Chemical & Materials Engineering, Jiangnan University, No. 1800 Lihu Avenue, Wuxi 214122, China
| | - Peng Shu
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, JNU-HBN Cosmetic Functional Molecular Innovation Joint Laboratory, School of Chemical & Materials Engineering, Jiangnan University, No. 1800 Lihu Avenue, Wuxi 214122, China
- HBN Research Institute and Biological Laboratory, Shenzhen Hujia Technology Co., Ltd., Shenzhen 518000, China
| | - Jing Wang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, JNU-HBN Cosmetic Functional Molecular Innovation Joint Laboratory, School of Chemical & Materials Engineering, Jiangnan University, No. 1800 Lihu Avenue, Wuxi 214122, China
| | - Hui Yan
- School of Pharmaceutical Sciences, Liaocheng University, Liaocheng, Shandong 252059, China
| | - Yongmin Zhang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, JNU-HBN Cosmetic Functional Molecular Innovation Joint Laboratory, School of Chemical & Materials Engineering, Jiangnan University, No. 1800 Lihu Avenue, Wuxi 214122, China
| |
Collapse
|
2
|
Nayak S, Servis MJ, Combs D, Szeliga K, Seifert S. Speciation and Organic Phase Structure in Nitric Acid Extraction with Trioctylamine. J Phys Chem B 2024; 128:3236-3248. [PMID: 38506558 DOI: 10.1021/acs.jpcb.3c08268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Understanding chemical speciation and intermolecular interactions in multicomponent liquids is essential to understanding their phase and chemical equilibria, which underpin chemical separation processes, including solvent extraction. Here we report on the extraction of nitric acid from its aqueous solutions into organic solutions of trioctylamine (TOA) in toluene, investigated with spectroscopic, X-ray scattering, and computational tools to understand molecular speciation in the organic phase and its relationship with the nanoscale structure of the organic phase. Trends in acid and water extraction clearly show two and three regimes, respectively, indicating different stoichiometric relationships, but speciation of HNO3, water, and amine in these regimes is not apparent. 1H NMR of the organic phase shows that there are at least two distinct acidic protons in the organic phase while ATR-FTIR results show that the organic phase with excess acid extraction is a mixture of trioctylammonium-nitrate ion pairs (TOAH·NO3), and undissociated HNO3 molecules. Comparison with DFT-computed IR spectra show that the chain-like configurations of TOAH·NO3·HNO3·H2O are favored over TOAH·NO3·H2O·HNO3, i.e., direct interaction between the nitrate and HNO3 molecules is more favored compared to a water-mediated interaction. SAXS of the organic phases were modeled as sums of Ornstein-Zernike (O-Z) scattering and a prepeak feature in the higher Q region that corresponds to extractant packing. The extraction of undissociated HNO3 by the ion pairs leads to an increased X-ray scattering contrast in the organic phase without any significant change in the correlation length. These results show that the organic phase nanostructure is more sensitive to the concentration of TOAH·NO3 and is relatively unaffected by excess acid extraction. These findings will enable a molecular understanding of the mechanisms behind metal extraction from acidic media with basic extractants.
Collapse
Affiliation(s)
- Srikanth Nayak
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Michael J Servis
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Derrick Combs
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Krystian Szeliga
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Soenke Seifert
- X-Ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, United States
| |
Collapse
|
3
|
Blahnik J, Schuster J, Müller R, Müller E, Kunz W. Surfactant-free microemulsions (SFMEs) as a template for porous polymer synthesis. J Colloid Interface Sci 2024; 655:371-382. [PMID: 37948811 DOI: 10.1016/j.jcis.2023.10.162] [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: 07/18/2023] [Revised: 10/25/2023] [Accepted: 10/31/2023] [Indexed: 11/12/2023]
Abstract
HYPOTHESIS Surfactant-free microemulsions (SFMEs) were recently reported to be an interesting medium for free-radical polymerizations. The aim of this study is to investigate the link between the morphology of PMMA monopolymers as well as PMMA-PHEMA-copolymers with the expected nature of the SFME before polymerization. A surfactant-based microemulsion with nonionic surfactants was investigated as a reference system. It is expected that the kind of mesostructuring of the SFME (oil-in-water-like, bicontinuous, inverse) corresponds with the latter polymer morphology, just like it is the case in surfactant-based systems. EXPERIMENTS Simple SFME systems composed of water, a hydrotrope (isopropanol or tert-butyl alcohol), and methyl methacrylate (MMA) as polymerizable oil as well as the more complex system comprising 2-hydroxyethyl methacrylate (HEMA) as an additional amphiphilic co-monomer, were investigated. A surfactant-based system using a mixture of Tergitol 15-S-12 and Synperonic A11-LQ-(TH) as surfactants, water, and MMA in the presence and absence of HEMA as polymerizable co-surfactant was investigated as a reference system. Structural analysis was done by recording (pseudo-)ternary phase diagrams, dynamic light scattering (DLS), and conductivity measurements. Polymerizations were performed using the oil-soluble initiator PEROXAN BCC at 318 K for 24 h with adjacent lyophilization. The morphology of dried polymers was determined by light microscopy, scanning electron microscopy, and BET adsorption isotherms. FINDINGS Porous polymers of different morphologies (from coagulations of droplet-like aggregates to sponge-like ones) in the size range of 200 nm up to some µm can be derived from previously mesostructured, surfactant-free mixtures. Previously unstructured, oil-rich regions lead to solid, transparent polymers without nanostructured morphologies. The surfactant-based reference system comprises remarkably similar phase behavior before polymerizations and similar polymer morphologies as the comparable surfactant-free system. This leads to the assumption that the hydrotropic behavior of HEMA and its interplay with MMA and water is the structure-giving factor in this system.
Collapse
Affiliation(s)
- Jonas Blahnik
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany
| | - Jennifer Schuster
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany
| | - Rainer Müller
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany
| | - Eva Müller
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany
| | - Werner Kunz
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany.
| |
Collapse
|
4
|
Li M, Wakata Y, Zeng H, Sun C. On the thermal response of multiscale nanodomains formed in trans-anethol/ethanol/water surfactant-free microemulsion. J Colloid Interface Sci 2023; 652:1944-1953. [PMID: 37690302 DOI: 10.1016/j.jcis.2023.08.166] [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: 04/26/2023] [Revised: 08/23/2023] [Accepted: 08/25/2023] [Indexed: 09/12/2023]
Abstract
HYPOTHESIS Surfactant-free microemulsion (SFME), an emerging phenomenology that occurs in the monophasic zone of a broad category of ternary mixtures 'hydrophobe/hydrotrope/water', has attracted extensive interests due to their unique physicochemical properties. The potential of this kind of ternary fluid for solubilization and drug delivery make them promising candidates in many industrial scenarios. EXPERIMENTS Here the thermodynamic behavior of these multiscale nanodomains formed in the ternary trans-anethol/ethanol/water system over a wide range of temperatures is explored. The macroscopic physical properties of the ternary solutions are characterized, with revealing the temperature dependence of refractive index and dynamic viscosity. FINDINGS With increasing temperature, the ternary system shows extended areas in the monophasic zone. We demonstrate that the phase behavior and the multiscale nanodomains formed in the monophasic zone can be precisely and reversibly tuned by altering the temperature. Increasing temperature can destroy the stability of the multiscale nanodomains in equilibrium, with an exponential decay in the scattering light intensity. Nevertheless, molecular-scale aggregates and mesoscopic droplets exhibit significantly different response behaviors to temperature stimuli. The temperature-sensitive nature of the ternary SFME system provides a crucial step forward exploring and industrializing its stability.
Collapse
Affiliation(s)
- Mingbo Li
- Center for Combustion Energy, Key laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China.
| | - Yuki Wakata
- Center for Combustion Energy, Key laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China
| | - Hao Zeng
- Center for Combustion Energy, Key laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China
| | - Chao Sun
- Center for Combustion Energy, Key laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China; Department of Engineering Mechanics, School of Aerospace Engineering, Tsinghua University, Beijing 100084, China.
| |
Collapse
|
5
|
Karafiludis S, Scoppola E, Wolf SE, Kochovski Z, Matzdorff D, Van Driessche AES, Hövelmann J, Emmerling F, Stawski TM. Evidence for liquid-liquid phase separation during the early stages of Mg-struvite formation. J Chem Phys 2023; 159:134503. [PMID: 37787132 DOI: 10.1063/5.0166278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 09/15/2023] [Indexed: 10/04/2023] Open
Abstract
The precipitation of struvite, a magnesium ammonium phosphate hexahydrate (MgNH4PO4 · 6H2O) mineral, from wastewater is a promising method for recovering phosphorous. While this process is commonly used in engineered environments, our understanding of the underlying mechanisms responsible for the formation of struvite crystals remains limited. Specifically, indirect evidence suggests the involvement of an amorphous precursor and the occurrence of multi-step processes in struvite formation, which would indicate non-classical paths of nucleation and crystallization. In this study, we use synchrotron-based in situ x-ray scattering complemented by cryogenic transmission electron microscopy to obtain new insights from the earliest stages of struvite formation. The holistic scattering data captured the structure of an entire assembly in a time-resolved manner. The structural features comprise the aqueous medium, the growing struvite crystals, and any potential heterogeneities or complex entities. By analysing the scattering data, we found that the onset of crystallization causes a perturbation in the structure of the surrounding aqueous medium. This perturbation is characterized by the occurrence and evolution of Ornstein-Zernike fluctuations on a scale of about 1 nm, suggesting a non-classical nature of the system. We interpret this phenomenon as a liquid-liquid phase separation, which gives rise to the formation of the amorphous precursor phase preceding actual crystal growth of struvite. Our microscopy results confirm that the formation of Mg-struvite includes a short-lived amorphous phase, lasting >10 s.
Collapse
Affiliation(s)
- Stephanos Karafiludis
- Federal Institute for Materials Research and Testing (BAM), Richard-Willstatter-Straße 11, 12489 Berlin, Germany
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - Ernesto Scoppola
- Biomaterials, Hierarchical Structure of Biological and Bio-inspired Materials, Max Planck Institute of Colloids and Interfaces, Potsdam 14476, Germany
| | - Stephan E Wolf
- Friedrich-Alexander University Erlangen-Nürnberg (FAU), Department of Materials Science and Engineering, Institute for Glass and Ceramics, Martensstr. 5, 91058 Erlangen, Germany
| | - Zdravko Kochovski
- Helmholtz-Zentrum Berlin for Materials and Energy, Hahn-Meitner Platz 1, 14109 Berlin, Germany
| | - David Matzdorff
- Helmholtz-Zentrum Berlin for Materials and Energy, Hahn-Meitner Platz 1, 14109 Berlin, Germany
| | - Alexander E S Van Driessche
- Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC - Universidad de Granada, Av. De las Palmeras 4, 18100 Armilla, Spain
| | - Jörn Hövelmann
- REMONDIS Production GmbH, Brunnenstraße 138, 44536 Lünen, Germany
| | - Franziska Emmerling
- Federal Institute for Materials Research and Testing (BAM), Richard-Willstatter-Straße 11, 12489 Berlin, Germany
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - Tomasz M Stawski
- Federal Institute for Materials Research and Testing (BAM), Richard-Willstatter-Straße 11, 12489 Berlin, Germany
| |
Collapse
|
6
|
Ernzen JR, Covas JA, Marcos-Fernández A, Fiorio R, Bianchi O. Soybean-Based Polyol as a Substitute of Fossil-Based Polyol on the Synthesis of Thermoplastic Polyurethanes: The Effect of Its Content on Morphological and Physicochemical Properties. Polymers (Basel) 2023; 15:4010. [PMID: 37836059 PMCID: PMC10574837 DOI: 10.3390/polym15194010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 09/29/2023] [Accepted: 10/02/2023] [Indexed: 10/15/2023] Open
Abstract
Thermoplastic polyurethanes (TPUs) are remarkably versatile polymers due to the wide range of raw materials available for their synthesis, resulting in physicochemical characteristics that can be tailored according to the specific requirements of their final applications. In this study, a renewable bio-based polyol obtained from soybean oil is used for the synthesis of TPU via reactive extrusion, and the influence of the bio-based polyol on the multi-phase structure and properties of the TPU is studied. As raw materials, 4,4'-diphenylmethane (MDI), 1,4-butanediol, a fossil-based polyester polyol, and a bio-based polyol are used. The fossil-based to soybean-based polyol ratios studied are 100/0, 99/1, 95/5, 90/10, 80/20, and 50/50% by weight, respectively. The TPUs were characterized by size exclusion chromatography (SEC), gel content analysis, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), dynamic mechanical analysis (DMA), and contact angle measurements. The results reveal that incorporating the renewable polyol enhances the compatibility between the rigid and flexible segments of the TPU. However, due to its high functionality, the addition of soybean-based polyol can promote cross-linking. This phenomenon reduces the density of hydrogen bonds within the material, also reducing polarity and restricting macromolecular mobility, as corroborated by higher glass transition temperature (Tg) values. Remarkably, the addition of small amounts of the bio-based polyol (up to 5 wt.% of the total polyol content) results in high-molecular-weight TPUs with lower polarity, combined with suitable processability and mechanical properties, thus broadening the range of applications and improving their sustainability.
Collapse
Affiliation(s)
- Juliano R. Ernzen
- Mantoflex Poliuretanos, Caxias do Sul 95045175, Brazil;
- PGMAT, Universidade de Caxias do Sul (UCS), Caxias do Sul 95070560, Brazil
| | - José A. Covas
- Department of Polymer Engineering, University of Minho, 4800-058 Guimarães, Portugal;
| | - Angel Marcos-Fernández
- Elastomers Group, Institute of Polymer Science and Technology (ICTP-CSIC), 28006 Madrid, Spain
- Interdisciplinary Platform for “Sustainable Plastics towards a Circular Economy” (SUSPLAST-CSIC), 28006 Madrid, Spain
| | - Rudinei Fiorio
- Department of Circular Chemical Engineering, Maastricht University, 6200 MD Geleen, The Netherlands;
| | - Otávio Bianchi
- PGMAT, Universidade de Caxias do Sul (UCS), Caxias do Sul 95070560, Brazil
- Department of Materials Engineering, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre 90040040, Brazil
| |
Collapse
|
7
|
Fink F, Stawski TM, Stockmann JM, Emmerling F, Falkenhagen J. Surface Modification of Kraft Lignin by Mechanochemical Processing with Sodium Percarbonate. Biomacromolecules 2023; 24:4274-4284. [PMID: 37561452 DOI: 10.1021/acs.biomac.3c00584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
In this article, we present a novel one-pot mechanochemical reaction for the surface activation of lignin. The process involves environmentally friendly oxidation with hydrogen peroxide, depolymerization of fractions with high molecular mass, and introduction of new carbonyl functions into the lignin backbone. Kraft lignin was ground with sodium percarbonate and sodium hydroxide in a ball mill at different time intervals. Analyses by infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR), size exclusion chromatography (SEC), dynamic vapor sorption (DVS), and small-angle X-ray scattering (SAXS) showed significant improvements. After only 5 min of reaction, there was a 47% reduction in mass-average molecular weight and an increase in carboxyl functionalities. Chemical activation resulted in an approximately 2.8-fold increase in water adsorption. Principal component analysis (PCA) provided further insight into the correlations between IR spectra and SAXS parameters.
Collapse
Affiliation(s)
- Friedrich Fink
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Strasse 11, 12489 Berlin, Germany
- Humboldt-Universität zu Berlin, Mathematische-Naturwissenschaftliche Fakultät, Unter den Linden 6, 10099 Berlin, Germany
| | - Tomasz M Stawski
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Strasse 11, 12489 Berlin, Germany
| | - Jörg M Stockmann
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Strasse 11, 12489 Berlin, Germany
| | - Franziska Emmerling
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Strasse 11, 12489 Berlin, Germany
- Humboldt-Universität zu Berlin, Mathematische-Naturwissenschaftliche Fakultät, Unter den Linden 6, 10099 Berlin, Germany
| | - Jana Falkenhagen
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Strasse 11, 12489 Berlin, Germany
| |
Collapse
|
8
|
Blahnik J, Krickl S, Schmid K, Müller E, Lupton J, Kunz W. Microemulsion and microsuspension polymerization of methyl methacrylate in surfactant-free microemulsions (SFME). J Colloid Interface Sci 2023; 648:755-767. [PMID: 37321095 DOI: 10.1016/j.jcis.2023.06.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/23/2023] [Accepted: 06/05/2023] [Indexed: 06/17/2023]
Abstract
HYPOTHESIS This article presents a free-radical polymerization method in a mesostructured system - free of any surfactants, protective colloids, or other auxiliary agents. It is applicable for a large variety of industrially relevant vinylic monomers. The aim of this work is to study the impact of surfactant-free mesostructuring on the polymerization kinetics and the polymer derived. EXPERIMENTS So-called surfactant-free microemulsions (SFME) were investigated as reaction media with a simple composition comprising water, a hydrotrope (ethanol, n-propanol, isopropanol, tert-butyl alcohol), and the monomer as the reactive oil phase (methyl methacrylate). Polymerization reactions were performed using oil-soluble, thermal- and UV-active initiators (surfactant-free microsuspension polymerization) and water-soluble, redox-active initiators (surfactant-free microemulsion polymerization). Structural analysis of the SFMEs used and the polymerization kinetics were followed by dynamic light scattering (DLS). Dried polymers were analyzed with regard to their conversion yield by mass balance, the corresponding molar masses were determined using gel permeation chromatography (GPC), and the morphology was investigated by light microscopy. FINDINGS All alcohols are suitable hydrotropes to form SFMEs, except for ethanol, which forms a molecularly disperse system. We observe significant differences in the polymerization kinetics and the molar masses of the polymers obtained. Ethanol leads to significantly higher molar masses. Within a system, higher concentrations of the other alcohols investigated give rise to less pronounced mesostructuring, lower conversions, and lower average molar masses. It could be demonstrated that the effective concentration of alcohol in the oil-rich pseudophases as well as the repulsive effect of the surfactant-free, alcohol-rich interphases constitute the relevant factors influencing polymerization. Concerning the morphology, the polymers derived range from powder-like polymers in the so-called "pre-Ouzo region" over porous-solid polymers in the bicontinuous region to dense, almost compacted, transparent polymers in unstructured regions, comparable to the findings for surfactant-based systems reported in the literature. Polymerizations in SFME comprise a new intermediate between well-known solution (i.e., molecularly dispersed) and microemulsion respectively microsuspension polymerization processes.
Collapse
Affiliation(s)
- Jonas Blahnik
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany
| | - Sebastian Krickl
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany
| | - Klaus Schmid
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany
| | - Eva Müller
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany
| | - John Lupton
- Institute of Experimental and Applied Physics, University of Regensburg, 93040 Regensburg, Germany
| | - Werner Kunz
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93040 Regensburg, Germany.
| |
Collapse
|
9
|
Schirone D, Gentile L, Olsson U, Palazzo G. Optimum formulation conditions for cationic surfactants via rheo-titration in turbulent regime. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
10
|
Sepulveda-Medina PI, Wang C, Li R, Fukuto M, Vogt BD. Influence of the Nature of Aliphatic Hydrophobic Physical Crosslinks on Water Crystallization in Copolymer Hydrogels. J Phys Chem B 2022; 126:5544-5554. [PMID: 35833757 DOI: 10.1021/acs.jpcb.2c02438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The local environment within a hydrogel influences the properties of water, including the propensity for ice crystallization. Water-swollen amphiphilic copolymers produce tunable nanoscale environments, which are defined by hydrophobic associations, for the water molecules. Here, the antifreeze properties for equilibrium-swollen amphiphilic copolymers with a common hydrophilic component, hydroxyethyl acrylate (HEA), but associated through crystalline (octadecyl acrylate, ODA) or rubbery (ethylhexyl acrylate, EHA) hydrophobic segments, are examined. Differences in the efficacy of the associations can be clearly enunciated from compositional solubility limits for the copolymers in water (<2.6 mol % ODA vs ≤14 mol % EHA), and these differences can be attributed to the strength of the association. The equilibrium-swollen HEA-ODA copolymers are viscoelastic solids, while the swollen HEA-EHA copolymers are viscoelastic liquids. Cooling these swollen copolymers to nearly 200 K induces some crystallization of the water, where the fraction of water frozen depends on the details of the nanostructure. Decreasing the mean free path of water by increasing the ODA composition from 10 to 25 mol % leads to fractionally more unfrozen water (66-87%). The swollen HEA-EHA copolymers only marginally inhibit ice (<13%) except with 45 mol % EHA, where nearly 60% of the water remains amorphous on cooling to 200 K. In general, the addition of the EHA leads to less effective ice inhibition than analogous covalently crosslinked HEA hydrogels (19.9 ± 1.8%). These results illustrate that fluidity of confining surfaces can provide pathways for critical nuclei to form and crystal growth to proceed.
Collapse
Affiliation(s)
- Pablo I Sepulveda-Medina
- School of Polymer Science and Polymer Engineering, University of Akron, Akron, Ohio 44325, United States
| | - Chao Wang
- School of Polymer Science and Polymer Engineering, University of Akron, Akron, Ohio 44325, United States
| | - Ruipeng Li
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Masafumi Fukuto
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Bryan D Vogt
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| |
Collapse
|
11
|
Li M, Yi L, Sun C. Spontaneously formed multiscale nano-domains in monophasic region of ternary solution. J Colloid Interface Sci 2022; 628:223-235. [DOI: 10.1016/j.jcis.2022.07.152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 07/23/2022] [Accepted: 07/25/2022] [Indexed: 10/16/2022]
|
12
|
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]
|
13
|
Liu Q, Wang J, Wu H, Zong S, Wang N, Wang T, Zhou L, Huang X, Hao H. Structure and pseudo-ternary phase diagram of water/Triton X-100/1-pentanol/cyclohexane microemulsion. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118425] [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]
|
14
|
Gentile L. Ferrihydrite nanoparticles entrapped in shear-induced multilamellar vesicles. J Colloid Interface Sci 2022; 606:1890-1896. [PMID: 34689045 DOI: 10.1016/j.jcis.2021.09.192] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/28/2021] [Accepted: 09/29/2021] [Indexed: 10/20/2022]
Abstract
HYPOTHESIS Ferrihydrite (Fh) nanoparticles are receiving considerable scientific interest due to their large reactive surface areas, crystalline structures, and nanoparticle morphology. They are of great importance in biogeochemical processes and have the ability to sequester hazardous and toxic substances. Here, the working hypothesis was to entrap fractal-like Fh nanoparticles, with a radius of gyration of 6.2 nm and a primary building block of polydisperse spheres with a radius of 0.8 nm, in a shear-induced multilamellar vesicle (MLV) state using a 40 wt% polyethylene glycol dodecyl ether surfactant. EXPERIMENTS Small- and Wide- Angle X-ray scattering revealed the equilibrium state of the non-ionic planar lamellar phase, the Fh dispersion, and their mixture. The MLV state was induced by using a shear flow in a Taylor-Couette geometry of a rheometer. FINDINGS The nonionic surfactant initially exhibited a lamellar gel phase with two distinct d-spacings of 11.0 and 9.7 nm, which collapsed into the MLV state under shear flow. The Fh nanoparticles induced bilayer attraction by suppressing lamellar layer undulations, decreasing the d-spacing. These results are helpful in the understanding of the relationship between nanoparticle size and nanoparticle-bilayers interactions and provides insight on Fh encapsulations in a kinetically stable MLVs state.
Collapse
Affiliation(s)
- Luigi Gentile
- Department of Chemistry, University of Bari "Aldo Moro", Via Orabona 4, Bari 70126, Italy; Center of Colloid and Surface Science (CSGI) Bari Unit, Via Orabona 4 Bari 70126, Italy.
| |
Collapse
|
15
|
Maunder JJ, Aguilar JA, Hodgkinson P, Cooper SJ. Structured ternary fluids as nanocrystal incubators for enhanced crystallization control. Chem Sci 2022; 13:13132-13140. [DOI: 10.1039/d2sc04413g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 10/23/2022] [Indexed: 11/21/2022] Open
Abstract
Crystallization in structured ternary fluids can proceed via higher nucleation rate and slower crystal growth pathways that are impossible to access in normal unstructured solutions. Hence, structured ternary fluids can act as nanocrystal incubators.
Collapse
Affiliation(s)
- J. J. Maunder
- Department of Chemistry, University of Durham, Durham DH1 3LE, UK
| | - J. A. Aguilar
- Department of Chemistry, University of Durham, Durham DH1 3LE, UK
| | - P. Hodgkinson
- Department of Chemistry, University of Durham, Durham DH1 3LE, UK
| | - S. J. Cooper
- Department of Chemistry, University of Durham, Durham DH1 3LE, UK
| |
Collapse
|
16
|
|
17
|
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: 61] [Impact Index Per Article: 20.3] [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
|
18
|
Sepulveda-Medina PI, Tyagi M, Wang C, Vogt BD. Water dynamics within nanostructured amphiphilic statistical copolymers from quasielastic neutron scattering. J Chem Phys 2021; 154:154903. [PMID: 33887940 DOI: 10.1063/5.0045341] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Understanding the properties of water under either soft or hard confinement has been an area of great interest, but nanostructured amphiphilic polymers that provide a secondary confinement have garnered significantly less attention. Here, a series of statistical copolymers of 2-hydroxyethyl acrylate (HEA) and 2-(N-ethylperfluorooctane sulfonamido)ethyl methacrylate (FOSM) are swollen to equilibrium in water to form nanostructured physically cross-linked hydrogels to probe the effect of soft confinement on the dynamics of water. Changing the composition of the copolymer from 10 to 21 mol. % FOSM decreases the average size of the assembled FOSM cross-link, but also the spacing between the cross-links in the hydrogels with the mean distance between the FOSM aggregates decreasing from 3.9 to 2.7 nm. The dynamics of water within the hydrogels were assessed with quasielastic neutron scattering. These hydrogels exhibit superior performance for inhibition of water crystallization on supercooling in comparison to analogous hydrogels with different hydrophilic copolymer chemistries. Despite the lower water crystallinity, the self-diffusion coefficient for these hydrogels from the copolymers of HEA and FOSM decreases precipitously below 260 K, which is a counter to the nearly temperature invariant water dynamics reported previously with an analogous hydrogel [Wiener et al., J. Phys. Chem. B 120, 5543 (2016)] that exhibits nearly temperature invariant dynamics to 220 K. These results point to chemistry dependent dynamics of water that is confined within amphiphilic hydrogels, where the interactions of water with the hydrophilic segments can qualitatively alter the temperature dependent dynamics of water in the supercooled state.
Collapse
Affiliation(s)
| | - Madhusudan Tyagi
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Chao Wang
- School of Polymer Science and Polymer Engineering, University of Akron, Akron, Ohio 44325, USA
| | - Bryan D Vogt
- School of Polymer Science and Polymer Engineering, University of Akron, Akron, Ohio 44325, USA
| |
Collapse
|
19
|
Prévost S, Krickl S, Marčelja S, Kunz W, Zemb T, Grillo I. Spontaneous Ouzo Emulsions Coexist with Pre-Ouzo Ultraflexible Microemulsions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:3817-3827. [PMID: 33724851 DOI: 10.1021/acs.langmuir.0c02935] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Even in the absence of surfactants, polymers, or particles, spontaneous emulsions produced by dilution with water can be stable over days. This "Ouzo effect" used by the industry is obtained by rapid dilution from an identified "pre-Ouzo" domain of composition where weak aggregates are present: nanometer-sized clusters covered by a surface layer enriched in a hydrotrope such as ethanol. In these systems, Ostwald ripening is not an effective destabilizing mechanism. Using in situ autodilution small-angle X-ray scattering (SAXS), we follow the morphological transitions occurring in a ternary mixture of water/n-octanol/ethanol throughout the monophasic and biphasic regions. This allows for the first time an online characterization of the multiscale coexisting microstructures. Small-angle neutron scattering (SANS) profiles on metastable emulsions as well as phase-separated samples complete the SAXS data, taking advantage of contrast variation via isotopic substitution. After crossing the phase boundary into the two-phase region, coexisting phases are both ternary solutions structured at the nanometer scale when the emulsion is stable. The transition from single phase to two phases is asymmetric around the plait point. When the initial concentration of the hydrotrope is below the minimum hydrotrope concentration (MHC), emulsification failure occurs, i.e., emulsions cream within seconds. Beyond MHC, the low interfacial tension between coexisting ternary fluids results in a Laplace pressure below 100 Pa, explaining the puzzling resilience of spontaneous emulsion to the universal mechanism of Ostwald ripening.
Collapse
Affiliation(s)
- Sylvain Prévost
- Institut Laue-Langevin, 71 Avenue des Martyrs, CS 20156, 38042 Grenoble Cedex 9, France
| | - Sebastian Krickl
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93053 Regensburg, Germany
| | - Stjepan Marčelja
- Department of Applied Mathematics, Research School of Physics & Engineering, Australian National University, Canberra, ACT 2601, Australia
| | - Werner Kunz
- Institute of Physical and Theoretical Chemistry, University of Regensburg, 93053 Regensburg, Germany
| | - Thomas Zemb
- Institut de Chimie Séparative de Marcoule, CEA, CNRS, ENSCM, Univ Montpellier, 30207 Marcoule, France
| | - Isabelle Grillo
- Institut Laue-Langevin, 71 Avenue des Martyrs, CS 20156, 38042 Grenoble Cedex 9, France
| |
Collapse
|
20
|
The Difference in Molecular Orientation and Interphase Structure of SiO 2/Shape Memory Polyurethane in Original, Programmed and Recovered States during Shape Memory Process. Polymers (Basel) 2020; 12:polym12091994. [PMID: 32887279 PMCID: PMC7564273 DOI: 10.3390/polym12091994] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 12/17/2022] Open
Abstract
In order to further understand the shape memory mechanism of a silicon dioxide/shape memory polyurethane (SiO2/SMPU) composite, the thermodynamic properties and shape memory behaviors of prepared SiO2/SMPU were characterized. Dynamic changes in the molecular orientation and interphase structures of SiO2/SMPU during a shape memory cycle were then discussed according to the small angle X-ray scattering theory, Guinier’s law, Porod approximation, and fractal dimension theorem. In this paper, a dynamic mechanical analyzer (DMA) helped to determine the glass transition start temperature (Tg) by taking the onset point of the sigmoidal change in the storage modulus, while transition temperature (Ttrans) was defined by the peak of tan δ, then the test and the calculated results indicated that the Tg of SiO2/SMPU was 50.4 °C, and the Ttrans of SiO2/SMPU was 72.18 °C. SiO2/SMPU showed good shape memory performance. The programmed SiO2/SMPU showed quite obvious microphase separation and molecular orientation. Large-size sheets and long-period structures were formed in the programmed SiO2/SMPU, which increases the electron density difference. Furthermore, some hard segments had been rearranged, and their gyration radii decreased. In addition, several defects formed at the interfaces of SiO2/SMPU, which caused the generation of space charges, thus leading to local electron density fluctuations. The blurred interphase structure and the intermediate layer formed in the programmed SiO2/SMPU and there was evident crystal damage and chemical bond breakage in the recovered SiO2/SMPU. Finally, the original and recovered SiO2/SMPU samples belong to the surface fractal system, but the programmed sample belongs to the mass fractal and reforms two-phase structures. This study provides an insight into the shape memory mechanism of the SiO2/SMPU composite.
Collapse
|
21
|
Liu Q, Wang J, Wu H, Zong S, Huang X, Wang T, Hao H. Manipulating of Crystal Morphology and Polymorph by Crystallization in Microemulsions. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c00700] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Qi Liu
- National Engineering Research Center of Industrial Crystallization Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Jingkang Wang
- National Engineering Research Center of Industrial Crystallization Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Hao Wu
- National Engineering Research Center of Industrial Crystallization Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Shuyi Zong
- National Engineering Research Center of Industrial Crystallization Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Xin Huang
- National Engineering Research Center of Industrial Crystallization Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Ting Wang
- National Engineering Research Center of Industrial Crystallization Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Hongxun Hao
- National Engineering Research Center of Industrial Crystallization Technology, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| |
Collapse
|
22
|
Combined molecular dynamics (MD) and small angle scattering (SAS) analysis of organization on a nanometer-scale in ternary solvent solutions containing a hydrotrope. J Colloid Interface Sci 2019; 540:623-633. [DOI: 10.1016/j.jcis.2019.01.037] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 01/09/2019] [Accepted: 01/10/2019] [Indexed: 11/18/2022]
|
23
|
Enami S, Ishizuka S, Colussi AJ. Chemical signatures of surface microheterogeneity on liquid mixtures. J Chem Phys 2019; 150:024702. [PMID: 30646725 DOI: 10.1063/1.5055684] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Many chemical reactions in Nature, the laboratory, and chemical industry occur in solvent mixtures that bring together species of dissimilar solubilities. Solvent mixtures are visually homogeneous, but are not randomly mixed at the molecular scale. In the all-important binary water-hydrotrope mixtures, small-angle neutron and dynamic light scattering experiments reveal the existence of short-lived (<50 ps), short-ranged (∼1 nm) concentration fluctuations. The presence of hydrophobic solutes stabilizes and extends such fluctuations into persistent, mesoscopic (10-100 nm) inhomogeneities. While the existence of inhomogeneities is well established, their impacts on reactivity are not fully understood. Here, we search for chemical signatures of inhomogeneities on the surfaces of W:X mixtures (W = water; X = acetonitrile, tetrahydrofuran, or 1,4-dioxane) by studying the reactions of Criegee intermediates (CIs) generated in situ from O3(g) addition to a hydrophobic olefin (OL) solute. Once formed, CIs isomerize to functionalized carboxylic acids (FC) or add water to produce α-hydroxy-hydroperoxides (HH), as detected by surface-specific, online pneumatic ionization mass spectrometry. Since only the formation of HH requires the presence of water, the dependence of the R = HH/FC ratio on water molar fraction x w expresses the accessibility of water to CIs on the surfaces of mixtures. The finding that R increases quasi-exponentially with x w in all solvent mixtures is consistent with CIs being preferentially produced (from their OL hydrophobic precursor) in X-rich, long-lived OL:X m W n interfacial clusters, rather than randomly dispersed on W:X surfaces. R vs x w dependences therefore reflect the average ⟨m, n⟩ composition of OL:X m W n interfacial clusters, as weighted by cluster reorganization dynamics. Water in large, rigid clusters could be less accessible to CIs than in smaller but more flexible clusters of lower water content. Since mesoscale inhomogeneities are intrinsic to most solvent mixtures, these phenomena should be quite general.
Collapse
Affiliation(s)
- Shinichi Enami
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan
| | - Shinnosuke Ishizuka
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan
| | - Agustín J Colussi
- Linde Center for Global Environmental Science, California Institute of Technology, Pasadena, California 91125, USA
| |
Collapse
|
24
|
Wang C, Wiener CG, Fukuto M, Li R, Yager KG, Weiss RA, Vogt BD. Strain rate dependent nanostructure of hydrogels with reversible hydrophobic associations during uniaxial extension. SOFT MATTER 2019; 15:227-236. [PMID: 30543258 DOI: 10.1039/c8sm02165a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
An energy dissipation mechanism during deformation is required to impart toughness to hydrogels. Here we describe how in situ small angle X-ray scattering (SAXS) provides insight into possible energy dissipation mechanisms for a tough hydrogel based on an amphiphilic copolymer where nanoscale associations of the hydrophobic moieties act as effective crosslinks. The mechanical properties of the hydrogels are intimately coupled with the nanostructure that provides reversible crosslinks and evolves during deformation. As the extension rate increases, more mechanical energy is dissipated from rearrangements of the crosslinks. The scattering is consistent with hopping of hydrophobes between the nanoscale aggregates as the primary rearrangement mechanism. This rearrangement changes the network conformation that leads to non-affine deformation, where the change in the nanostructure dimension from SAXS is less than 15% of the total macroscopic strain. These nanostructure changes are rate dependent and correlated with the relaxation time of the hydrogel. At low strain rate (0.15% s-1), no significant change of the nanostructure was observed, whereas at higher strain rates (1.5% s-1 and 8.4% s-1) significant nanostructure anisotropy occurred during extension. These differences are attributed to the ability for the network chains to rearrange on the time scale of the deformation; when the characteristic time for extension is longer than the average segmental relaxation time, no significant change in nanostructure occurs on uniaxial extension. These results illustrate the importance of strain rate in the mechanical characterization and consideration of relaxation time in the design of tough hydrogels with reversible crosslinks.
Collapse
Affiliation(s)
- Chao Wang
- Department of Polymer Engineering, University of Akron, Akron, OH 44325, USA.
| | | | | | | | | | | | | |
Collapse
|
25
|
|
26
|
Chiappisi L, Grillo I. Looking into Limoncello: The Structure of the Italian Liquor Revealed by Small-Angle Neutron Scattering. ACS OMEGA 2018; 3:15407-15415. [PMID: 31458197 PMCID: PMC6644077 DOI: 10.1021/acsomega.8b01858] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 10/29/2018] [Indexed: 05/30/2023]
Abstract
Limoncello, the Italian liquor based on lemon essential oils, is becoming increasingly popular around the world. This digestive is not only an iconic representative of Italian food culture, but it is also a complex colloidal system, made of essential oils, ethanol, sucrose, and water. Smell, aroma, taste, and appearance of Limoncello do, of course, depend on the components, in particular on the peculiar essential oil mixture. Accordingly, several studies are available in the literature investigating the composition of various Limoncellos. However, the microscopic structure plays an equally important role when it comes to the sensory properties of food and beverages. In this work, small-angle neutron scattering was used to probe the microscopic structure of Limoncello, revealing the presence of spontaneously formed 100 nm-sized droplets over a large range of composition and temperature. The results are not limited to this famous drink but can be extended to the rapidly developing formulations based on water-insoluble oils, water, and alcohols.
Collapse
Affiliation(s)
- Leonardo Chiappisi
- Stranski
Laboratorium für Physikalische Chemie und Theoretische Chemie,
Institut für Chemie, Technische Universität
Berlin, Strasse des 17. Juni 124, Sekr. TC7, , D-10623 Berlin, Germany
- Institut
Max von Laue−Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France
| | - Isabelle Grillo
- Institut
Max von Laue−Paul Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France
| |
Collapse
|
27
|
Krickl S, Touraud D, Bauduin P, Zinn T, Kunz W. Enzyme activity of horseradish peroxidase in surfactant-free microemulsions. J Colloid Interface Sci 2018; 516:466-475. [DOI: 10.1016/j.jcis.2018.01.077] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 01/22/2018] [Accepted: 01/22/2018] [Indexed: 11/28/2022]
|
28
|
Hollamby MJ, Smith CF, Britton MM, Danks AE, Schnepp Z, Grillo I, Pauw BR, Kishimura A, Nakanishi T. The aggregation of an alkyl-C 60 derivative as a function of concentration, temperature and solvent type. Phys Chem Chem Phys 2018; 20:3373-3380. [PMID: 29260811 DOI: 10.1039/c7cp06348b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Contrast-variation small-angle neutron scattering (CV-SANS), small-angle X-ray scattering (SAXS), nuclear magnetic resonance (NMR) measurements of diffusion and isothermal titration calorimetry (ITC) are used to gain insight into the aggregation of an alkyl-C60 derivative, molecule 1, in n-hexane, n-decane and toluene as a function of concentration and temperature. Results point to an associative mechanism of aggregation similar to other commonly associating molecules, including non-ionic surfactants or asphaltenes in non-aqueous solvents. Little aggregation is detected in toluene, but small micelle-like structures form in n-alkane solvents, which have a C60-rich core and alkyl-rich shell. The greatest aggregation extent is found in n-hexane, and at 0.1 M the micelles of 1 comprise around 6 molecules at 25 °C. These micelles become smaller when the concentration is lowered, or if the solvent is changed to n-decane. The solution structure is also affected by temperature, with a slightly larger aggregation extent at 10 °C than at 25 °C. At higher concentrations, for example in solutions of 1 above 0.3 M in n-decane, a bicontinuous network becomes apparent. Overall, these findings aid our understanding of the factors driving the assembly of alkyl-π-conjugated hydrophobic amphiphiles such as 1 in solution and thereby represent a step towards the ultimate goal of exploiting this phenomenon to form materials with well-defined order.
Collapse
Affiliation(s)
- Martin J Hollamby
- School of Physical and Geographical Sciences, Keele University, Keele, Staffordshire, ST55BG, UK.
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Cabry CP, D’Andrea L, Shimizu K, Grillo I, Li P, Rogers S, Bruce DW, Canongia Lopes JN, Slattery JM. Exploring the bulk-phase structure of ionic liquid mixtures using small-angle neutron scattering. Faraday Discuss 2018; 206:265-289. [DOI: 10.1039/c7fd00167c] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Small-angle neutron scattering experiments, supported by molecular dynamics simulations, have been performed on a range of compositions of the [C2mim]1−x[C12mim]x[Tf2N] ionic liquid mixture system.
Collapse
Affiliation(s)
| | - Lucía D’Andrea
- Department of Chemistry
- University of York
- York YO10 5DD
- UK
| | - Karina Shimizu
- Centro de Química Estrutural
- IST
- Universidade de Lisboa
- 1049-001 Lisboa
- Portugal
| | | | - Peixun Li
- ISIS
- Science & Technology Facilities Council
- Rutherford Appleton Laboratory
- UK
| | - Sarah Rogers
- ISIS
- Science & Technology Facilities Council
- Rutherford Appleton Laboratory
- UK
| | | | | | | |
Collapse
|
30
|
Shimizu S, Matubayasi N. Statistical thermodynamic foundation for mesoscale aggregation in ternary mixtures. Phys Chem Chem Phys 2018; 20:13777-13784. [DOI: 10.1039/c8cp01207e] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The origin of persistent mesoscale aggregation around the plait point has been clarified from statistical thermodynamics and differential geometry.
Collapse
Affiliation(s)
- Seishi Shimizu
- York Structural Biology Laboratory
- Department of Chemistry
- University of York
- York YO10 5DD
- UK
| | - Nobuyuki Matubayasi
- Division of Chemical Engineering, Graduate School of Engineering Science
- Osaka University
- Osaka 560-8531
- Japan
- Elements Strategy Initiative for Catalysts and Batteries
| |
Collapse
|
31
|
Grimaldi N, Rojas PE, Stehle S, Cordoba A, Schweins R, Sala S, Luelsdorf S, Piña D, Veciana J, Faraudo J, Triolo A, Braeuer AS, Ventosa N. Pressure-Responsive, Surfactant-Free CO 2-Based Nanostructured Fluids. ACS NANO 2017; 11:10774-10784. [PMID: 28846386 PMCID: PMC5707624 DOI: 10.1021/acsnano.7b02500] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 08/28/2017] [Indexed: 06/07/2023]
Abstract
Microemulsions are extensively used in advanced material and chemical processing. However, considerable amounts of surfactant are needed for their formulation, which is a drawback due to both economic and ecological reasons. Here, we describe the nanostructuration of recently discovered surfactant-free, carbon dioxide (CO2)-based microemulsion-like systems in a water/organic-solvent/CO2 pressurized ternary mixture. "Water-rich" nanodomains embedded into a "water-depleted" matrix have been observed and characterized by the combination of Raman spectroscopy, molecular dynamics simulations, and small-angle neutron scattering. These single-phase fluids show a reversible, pressure-responsive nanostructuration; the "water-rich" nanodomains at a given pressure can be instantaneously degraded/expanded by increasing/decreasing the pressure, resulting in a reversible, rapid, and homogeneous mixing/demixing of their content. This pressure-triggered responsiveness, together with other inherent features of these fluids, such as the absence of any contaminant in the ternary mixture (e.g., surfactant), their spontaneous formation, and their solvation capability (enabling the dissolution of both hydrophobic and hydrophilic molecules), make them appealing complex fluid systems to be used in molecular material processing and in chemical engineering.
Collapse
Affiliation(s)
- Natascia Grimaldi
- Institut
de Ciencia de Materials de Barcelona (ICMAB-CSIC) and Nanomol Technologies
SA, Modul de Recerca B, Campus UAB, 08193 Bellaterra, Spain
| | - Paula Elena Rojas
- Institut
de Ciencia de Materials de Barcelona (ICMAB-CSIC) and Nanomol Technologies
SA, Modul de Recerca B, Campus UAB, 08193 Bellaterra, Spain
- Centro
de Investigacion Biomedica en Red de Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid, Spain
| | - Simon Stehle
- Lehrstuhl
für Technische Thermodynamik (LTT), Friedrich-Alexander-Universitaet Erlangen-Nuernberg (FAU), Am Weichselgarten 8, 91058 Erlangen, Germany
- Erlangen
Graduate School in Advanced Optical Technologies (SAOT), Friedrich Alexander-Universitaet Erlangen-Nuernberg
(FAU), Paul-Gordan-Straße
6, 91052 Erlangen, Germany
| | - Alba Cordoba
- Institut
de Ciencia de Materials de Barcelona (ICMAB-CSIC) and Nanomol Technologies
SA, Modul de Recerca B, Campus UAB, 08193 Bellaterra, Spain
- Centro
de Investigacion Biomedica en Red de Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid, Spain
| | - Ralf Schweins
- Large
Scale Structures Group, Institut Laue-Langevin, 71 Avenue des Martyrs, CS 20156, F-38042 Grenoble Cedex 9, France
| | - Santi Sala
- Institut
de Ciencia de Materials de Barcelona (ICMAB-CSIC) and Nanomol Technologies
SA, Modul de Recerca B, Campus UAB, 08193 Bellaterra, Spain
- Centro
de Investigacion Biomedica en Red de Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid, Spain
| | - Stefan Luelsdorf
- Institut
für Physikalische Chemie, Universität
Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - David Piña
- Institut
de Ciencia de Materials de Barcelona (ICMAB-CSIC) and Nanomol Technologies
SA, Modul de Recerca B, Campus UAB, 08193 Bellaterra, Spain
- Centro
de Investigacion Biomedica en Red de Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid, Spain
| | - Jaume Veciana
- Institut
de Ciencia de Materials de Barcelona (ICMAB-CSIC) and Nanomol Technologies
SA, Modul de Recerca B, Campus UAB, 08193 Bellaterra, Spain
- Centro
de Investigacion Biomedica en Red de Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid, Spain
| | - Jordi Faraudo
- Institut
de Ciencia de Materials de Barcelona (ICMAB-CSIC) and Nanomol Technologies
SA, Modul de Recerca B, Campus UAB, 08193 Bellaterra, Spain
| | - Alessandro Triolo
- Laboratorio
Liquidi Ionici, Istituto di Struttura della
Materia-CNR (ISM-CNR), Rome 00133, Italy
| | - Andreas Siegfried Braeuer
- Lehrstuhl
für Technische Thermodynamik (LTT), Friedrich-Alexander-Universitaet Erlangen-Nuernberg (FAU), Am Weichselgarten 8, 91058 Erlangen, Germany
- Erlangen
Graduate School in Advanced Optical Technologies (SAOT), Friedrich Alexander-Universitaet Erlangen-Nuernberg
(FAU), Paul-Gordan-Straße
6, 91052 Erlangen, Germany
| | - Nora Ventosa
- Institut
de Ciencia de Materials de Barcelona (ICMAB-CSIC) and Nanomol Technologies
SA, Modul de Recerca B, Campus UAB, 08193 Bellaterra, Spain
- Centro
de Investigacion Biomedica en Red de Bioingenieria, Biomateriales y Nanomedicina (CIBER-BBN), 28029 Madrid, Spain
| |
Collapse
|
32
|
Prévost S, Gradzielski M, Zemb T. Self-assembly, phase behaviour and structural behaviour as observed by scattering for classical and non-classical microemulsions. Adv Colloid Interface Sci 2017; 247:374-396. [PMID: 28780230 DOI: 10.1016/j.cis.2017.07.022] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Revised: 07/17/2017] [Accepted: 07/17/2017] [Indexed: 11/16/2022]
Abstract
In this review, we discuss the conditions for forming microemulsions, systems which are thermodynamically stable mixtures of oil and water made stable by the presence of an interfacial film containing surface active molecules. There are several types of microemulsions, depending largely on the stiffness of the amphiphilic monolayer that separates the oily and the aqueous micro-domain. We first discuss and compare the phase behaviour of these different types, starting from the classical microemulsion made from a flexible surfactant film but then also moving on to less classical situations: this occurs when the interfacial film is stiff or when microemulsions are formed in the absence of a classical surfactant. In the second part, we relate these different microemulsion types to the structural features as can be determined via different methodologies by small angle scattering (SAS). Using absolute scaling, general theorems as well as fitting under constraints or to pre-supposed shapes in real space or correlation functions in reciprocal space allows to classify all microemulsions into classical flexible, rigid or ultra-flexible microemulsions with either globular, connected cylinder of locally flat interfaces, with the corresponding conductivity and phase stability properties.
Collapse
Affiliation(s)
| | - Michael Gradzielski
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Technische Universität Berlin, D-10623 Berlin, Germany.
| | - Thomas Zemb
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Technische Universität Berlin, D-10623 Berlin, Germany; Institut de Chimie Séparative de Marcoule (ICSM), Bldg 426, Centre de Marcoule, F-30207 Bagnols sur Cèze, France
| |
Collapse
|
33
|
Knight AW, Qiao B, Chiarizia R, Ferru G, Forbes T, Ellis RJ, Soderholm L. Subtle Effects of Aliphatic Alcohol Structure on Water Extraction and Solute Aggregation in Biphasic Water/n-Dodecane. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:3776-3786. [PMID: 28375007 DOI: 10.1021/acs.langmuir.6b04657] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Organic phase aggregation behavior of 1-octanol and its structural isomer, 2-ethylhexanol, in a biphasic n-dodecane-water system is studied with a combination of physical measurement, small-angle X-ray scattering (SAXS), and atomistic molecular dynamic simulations. Physical properties of the organic phases are probed following their mixing and equilibration with immiscible water phases. Studies reveal that the interfacial tension decreases as a function of increasing alcohol concentration over the solubility range of the alcohol with no evidence for a critical aggregate concentration (cac). An uptake of water into the organic phases is quantified, as a function of alcohol content, by Karl Fischer titrations. The extraction of water into dodecane was further assessed as a function of alcohol concentration via the slope-analysis method sometimes employed in chemical separations. This method provides a qualitative understanding of solute (water/alcohol) aggregation in the organic phase. The physical results are supported by analyses of SAXS data that reveals an emergence of aggregates in n-dodecane at elevated alcohol concentrations. The observed aggregate structure is dependent on the alcohol tail group geometry, consistent with surfactant packing parameter. The formation of these aggregates is discussed at a molecular level, where alcohol-alcohol and alcohol-water H-bonding interactions likely dominate the occurrence and morphology of the aggregates.
Collapse
Affiliation(s)
- Andrew W Knight
- Department of Chemistry, E373 CB, University of Iowa , Iowa City, Iowa 52246, United States
| | | | | | | | - Tori Forbes
- Department of Chemistry, E373 CB, University of Iowa , Iowa City, Iowa 52246, United States
| | | | | |
Collapse
|
34
|
Gradzielski M, Allen AJ. Introduction to the special issue on small-angle scattering. J Appl Crystallogr 2016; 49:1858-1860. [PMID: 27980505 PMCID: PMC5139987 DOI: 10.1107/s160057671601904x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
This open-access collection of 11 selected articles covers a small but quite diverse and interesting part of the much wider range of scientific topics presented at the 16th International Conference on Small-Angle Scattering (SAS2015) in Berlin. The topics contained here describe the particular directions in which small-angle scattering is developing at the current moment and which will become increasingly important in the future. The virtual special issue is available at http://journals.iucr.org/special_issues/2016/sas2015/.
Collapse
Affiliation(s)
- Michael Gradzielski
- Stranski Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Technische Universität Berlin , Strasse des 17 Juni 124, 10623 Berlin, Germany
| | - Andrew J Allen
- Materials Measurement Science Division, National Institute of Standards and Technology (NIST) , 100 Bureau Drive, Gaithersburg, MD 20899, USA
| |
Collapse
|