DOCSLIB.ORG

First Fluorinated Zwitterionic Micelle with Unusually Slow Exchange in an Ionic Liquid

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
First Fluorinated Zwitterionic Micelle with Unusually Slow Exchange in an Ionic Liquid Article pubs.acs.org/Langmuir First Fluorinated Zwitterionic Micelle with Unusually Slow Exchange in an Ionic Liquid Xiaolin Wang, Panfeng Long, Shuli Dong, and Jingcheng Hao* Key Laboratory of Colloid and Interface Chemistry and Key Laboratory of Special Aggregated Materials, Shandong University, Ministry of Education, Jinan 250100, China *S Supporting Information ABSTRACT: The micellization of a fluorinated zwitterionic surfactant in ethylammonium nitrate (EAN) was investigated. The freeze-fracture transmission electron microscope (FF-TEM) observations confirm the formation of spherical micelles with the average diameter 25.45 ± 3.74 nm. The micellization is an entropy-driven process at low temperature but an enthalpy-driven process at high temperature. Two sets of 19F NMR signals above the critical micelle concentration (cmc) indicate that the unusually slow exchange between micelles and monomers exists in ionic liquid; meanwhile, surfactant molecules are more inclined to stay in micelle states instead of monomer states at higher concentration. Through the analysis of Δν the half line width ( 1/2), we can obtain the kinetic information of fluorinated zwitterionic micellization in an ionic liquid. ■ INTRODUCTION Due to their attractive properties, such as negligible volatility, low melting points, outstanding chemical and thermal stabilities, high ionic conductivity, and a relatively wide 1−5 electrochemical potential window, room-temperature ionic Figure 1. Chemical structure of PDSPDA. liquids (RTILs) have attracted considerable attention on chemical applications especially being treated as green solvents monomers was observed, showing the long lifetime of the for self-assembly of amphiphilic molecules. The first RTIL was fl 6 uorinated zwitterionic micelles in RTIL. To the best of our ethylammonium nitrate (EAN) reported by Walden in 1914. It knowledge, it is the first report for surfactant micelles in RTIL is the most extensively studied protic ionic liquid because of its with an unusually slow exchange, which should have a profound 7,8 similarities to water, and the most water-like property is that understanding for the surfactant aggregates in ionic liquid it can also form a three-dimensional hydrogen-bonded media. network.9 Evans and co-workers first provided evidence for the existence of hydrogen-bonded network in EAN; therefore, ■ EXPERIMENTAL SECTION ff amphiphilic molecules can self-assemble to di erent aggregates Chemicals and Materials. Polyfluorinated-2-dodecenyl (3- in EAN through the solvophobic interactions similar to the sulfate) propyl dimethyl ammonium (C9F19CF CHCH2N- 7,10,11 hydrophobic interactions in water. Studies about (CH3)2(CH2)3OSO3, PDSPDA) was a gift from Hoechst Aktienge- aggregates formed in EAN were mainly concentrated on sellschaft Werk, Gendorf (Frankfurt-am-Main, Germany). Ethyl- micelles7 and liquid crystals.12 Vesicles of Zn2+−fluorous ammonium nitrate (EAN) was synthesized according to the method 15 − surfactant or the mixture of Zn2+−fluorous surfactant/ reported by Evans et al. The aqueous solution of ethylamine (65 70 zwitterionic surfactant in RTILs13 and DDAB in EAN were wt %) was cooled in an ice bath, and 3 mol/L nitric acid was added 14 into it dropwise by stirring. The solution was stirred over two hours observed. Although a lot of work has been done to investigate fi 15−19 after nishing the addition of the nitric acid. Most of the water from the micellization of amphiphilic molecules in RTILs, the the crude product was removed with a rotary evaporator at 60 °C for mechanism is still controversial. Rare studies have been about three hours. To remove the remaining water, we first swept the reported concerning the micellization of fluorinated surfactants product by blowing the nitrogen and then performed the suction − in RTILs because they are difficult to dissolve in RTILs.20 22 In filtration under the 80 °C water bath by using an oil pump. Pure EAN the present work, we investigate the micellization of a was obtained and stored in the dry cabinet. Its melting point is 14 °C, 7,15 3 fluorinated zwitterionic surfactant, polyfluorinated-2-dodecenyl agreeing well with former reports, and the density is 1.2 g/cm (25 (3-sulfate) propyl dimethyl ammonium (C9F19CF CHCH2N- (CH3)2(CH2)3OSO3, PDSPDA, Figure 1), in EAN through the Received: July 30, 2013 methods of surface tension, 19F NMR, and FF-TEM measure- Revised: October 31, 2013 ments. Unusually slow exchange between micelles and Published: October 31, 2013 © 2013 American Chemical Society 14380 dx.doi.org/10.1021/la402937w | Langmuir 2013, 29, 14380−14385 Langmuir Article solvophobic interaction of tails and the interactions of headgroups. Over the entire temperature range, the contribu- tion of the enthalpy term to the micellization is more dominant than the entropy term. Both the solvation of headgroups and properties of the RTIL and the fluorinated surfactant contribute to the unusually slow exchange of surfactant molecules between micelles and monomers. With the increase of surfactant concentration, the micelles have a longer lifetime because of the increase of aggregation number. Since studies for the micellization of fluorinated surfactants in RTILs are rare, our investigation could provide a deeper understanding for the micellization mechanism in RTIL media. ■ ASSOCIATED CONTENT Δν 19 Figure 7. Half line width 1/2(Hz) of F NMR signals for the *S Supporting Information − terminal CF3 group in micelle state as a function of PDSPDA Characterizations of EAN, the micelle diameter distribution, concentration in EAN. and dynamic light scattering results. This material is available free of charge via the Internet at http://pubs.acs.org. testing sample is 2.5 mmol/L, and the temperature is 25 °C. ± Obvious spherical micelles with the average diameter 25.45 ■ AUTHOR INFORMATION 3.74 nm can be observed in the FF-TEM image (Figure 8). Corresponding Author *E-mail: [email protected]. Tel.: +86-531-88366074. Fax: +86- 531-88564750. Notes The authors declare no competing financial interest. ■ ACKNOWLEDGMENTS This work was financially supported by the NSFC (Grant No. 21033005 & 21273134) and the National Basic Research Program of China (973 Program, 2009CB930103). Figure 8. A typical FF-TEM image for PDSPDA micelles in EAN. ■ REFERENCES cPDSPDA = 2.5 mmol/L. (1) Welton, T. Room-Temperature Ionic Liquids. Solvents for Synthesis and Catalysis. Chem. Rev. 1999, 99, 2071−2083. Dynamic light scattering (DLS) measurements for the sample (2) Hussey, C. L. Room Temperature Haloaluminate Ionic Liquids. solution of 2.5 mmol/L PDSPDA in EAN at 25 °C were also Novel Solvents for Transition Metal Solution Chemistry. Pure Appl. fi Chem. 1988, 60, 1763−1772. performed to further con rm the size of micelles, and the range “ ” of the hydrodynamic radius (R )is30−50 nm (see Figure S4, (3) Wasserscheid, P.; Keim, W. Ionic Liquids-New Solutions for h Transition Metal Catalysis. Angew. Chem., Int. Ed. 2000, 39, 3772− SI). Because the hydrodynamic radius is always larger than the 49,50 3789. actual size, it can be assumed that micelles with large (4) Anderson, J. L.; Ding, J.; Welton, T.; Armstrong, D. W. diameters assuredly formed in this system. The micelles formed Characterizing Ionic Liquids On the Basis of Multiple Solvation by the fluorinated zwitterionic surfactant in EAN are much Interactions. J. Am. Chem. Soc. 2002, 124, 14247−14254. larger than those of some cationic surfactants with hydrocarbon (5) Dieter, K. M.; Dymek, C. J., Jr.; Heimer, N. E.; Rovang, J. W.; chains in EAN15 and the conventional micelles formed in Wilkes, J. S. Ionic Structure and Interactions in 1-Methyl-3- aqueous solutions normally with several nanometer in size. ethylimidazolium Chloride-AlCl3 Molten Salts. J. Am. Chem. Soc. Although there is no clear explanation for the larger size of 1988, 110, 2722−2726. micelles in our observations, they confirmed that the size of (6) Walden, P. Molecular Weight and Electrical Conductivity of − − micelles in ionic liquids is apparently larger,17,20 22 and much Several Fused Salts. Bull. Acad. Imper. Sci. 1914, 1800, 405 422. (7) Evans, D. F.; Yamauchi, A.; Roman, R.; Casassa, E. Z. Micelle further characterization will be needed. For example, Anderson Formation in Ethylammonium Nitrate, a Low-melting Fused Salt. J. et al. investigated that the size of micelles in ionic liquid − 17 Colloid Interface Sci. 1982, 88,89 96. solutions is apparently larger. For their measurements of Brij (8) Greaves, T. L.; Drummond, C. J. Protic Ionic Liquids: Properties 700 in ionic liquid 1-butyl-3-methyl imidazolium hexafluor- and Applications. Chem. Rev. 2008, 108, 206−237. ophosphate (BMIM-PF6), they observed that, when the (9) Fumino, K.; Wulf, A.; Ludwig, R. Hydrogen Bonding in Protic concentrations are somewhat lower than the cmc, premicellar Ionic Liquids: Reminiscent of Water. Angew. Chem., Int. Ed. 2009, 48, aggregates were found with an aggregation number of 4 and a 3184−3186. radius of gyration of 31.4 ± 4.4 nm was calculated. (10) Evans, D. F.; Chen, S.; Schriver, G. W.; Arnett, E. M. Thermodynamics of Solution of Nonpolar Gases in a Fused Salt. ■ CONCLUSIONS “Hydrophobic Bonding” Behavior in a Nonaqueous System. J. Am. Chem. Soc. 1981, 103, 481−482. In summary, we investigated the thermodynamic and kinetic (11) Ray, A. Solvophobic Interactions and Micelle Formation in micellization mechanism of a fluorinated zwitterionic surfactant Structure Forming Nonaqueous Solvents. Nature 1971, 231, 313−315. in EAN. The cmc variation demonstrates that the influence of (12) Araos, M. U.; Warr, G. G. Self-Assembly of Nonionic temperature on the micellization is embodied in both the Surfactants into Lyotropic Liquid Crystals in Ethylammonium Nitrate, 14384 dx.doi.org/10.1021/la402937w | Langmuir 2013, 29, 14380−14385.
Load more

Recommended publications
  • 03 Amine Chamber Studies.Pdf
    90 Chapter 3 Secondary Aerosol Formation from Atmospheric Reactions of Aliphatic Amines* ______________________ *This chapter is reproduced by permission from “Secondary aerosol formation from atmospheric reactions of aliphatic amines.” by S.M. Murphy, A. Sorooshian, J. H. Kroll, N. L. Ng, P. Chhabra, C. Tong, J.D. Surratt, E. Knipping, R. C. Flagan, and J. H. Seinfeld, Atmospheric Chemistry and Physics, 7(9), 2313-2337, 2007. Copyright 2007 Authors. This work is licensed under a Creative Commons License. 91 3.1 Abstract Although aliphatic amines have been detected in both urban and rural atmospheric aerosols, little is known about the chemistry leading to particle formation or the potential aerosol yields from reactions of gas-phase amines. We present here the first systematic study of aerosol formation from the atmospheric reactions of amines. Based on laboratory chamber experiments and theoretical calculations, we evaluate aerosol formation from reaction of OH, ozone, and nitric acid with trimethylamine, methylamine, triethylamine, diethylamine, ethylamine, and ethanolamine. Entropies of formation for alkylammonium nitrate salts are estimated by molecular dynamics calculations enabling us to estimate equilibrium constants for the reactions of amines with nitric acid. Though subject to significant uncertainty, the calculated dissociation equilibrium constant for diethy- lammonium nitrate is found to be sufficiently small to allow for its atmospheric formation, even in the presence of ammonia which competes for available nitric acid. Experimental chamber studies indicate that the dissociation equilibrium constant for triethylammonium nitrate is of the same order of magnitude as that for ammonium nitrate. All amines studied form aerosol when photooxidized in the presence of NOx with the majority of the aerosol mass present at the peak of aerosol growth consisting of + aminium (R3NH ) nitrate salts, which repartition back to the gas phase as the parent amine is consumed.
    [Show full text]
  • Ionic Liquids in Synthesis
    P. Wasserscheid and T. Welton (Eds.) Ionic Liquids in Synthesis P. Wasserscheid and T. Welton (Eds.) Ionic Liquids in Synthesis Related Titles from WILEY-VCH P.G. Jessop and W. Leitner (eds.) Chemical Synthesis Using Supercritical Fluids 1999. 500 pages. Hardcover. ISBN 3-527-29605-0 F. Zaragoza Dörwald (ed.) Organic Synthesis on Solid Phase Supports, Linkers, Reactions 2nd Edition, 2002. ca. 580 pages. Hardcover. ISBN 3-527-30603-X A. Loupy (ed.) Microwaves in Organic Synthesis 2002. ca. 350 pages. Hardcover. ISBN 3-527-30514-9 K. Tanaka (ed.) Solvent-free Organic Synthesis 2003. ca, 300 pages. Hardcover. ISBN 3-527-30612-9 P. Wasserscheid and T. Welton (Eds.) Ionic Liquids in Synthesis Volume Editors This book was carefully produced. Never- theless, editors, authors and publisher do Dr. Peter Wasserscheid not warrant the information contained RWTH Aachen therein to be free of errors. Readers are Institute for Technical and advised to keep in mind that statements, Macromolecular Chemistry data, illustrations, procedural details or Worringer Weg 1 other items may inadvertently be inaccurate. 52074 Aachen Germany Library of Congress Card No.: applied for A catalogue record for this book is available Dr. Thomas Welton from the British Library. Imperial College of Science, Technology and Medicine Bibliographic information published by Department of Chemistry Die Deutsche Bibliothek South Kensington Die Deutsche Bibliothek lists this publica- London SW7 2AY tion in the Deutsche Nationalbibliografie; UK detailed bibliographic data is available in the Internet at http://dnb.ddb.de © 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim All rights reserved (including those of trans- lation in other languages).
    [Show full text]
  • Interfacial Properties of Mercury/Ethylammonium Nitrate
    Interfacial properties of mercury/ethylammonium nitrate ionic liquid+water system: Electrocapillarity, surface charge and differential capacitance Malika Ammam, Dung Di Caprio, Laurent Gaillon To cite this version: Malika Ammam, Dung Di Caprio, Laurent Gaillon. Interfacial properties of mercury/ethylammonium nitrate ionic liquid+water system: Electrocapillarity, surface charge and differential capacitance. Elec- trochimica Acta, Elsevier, 2012, 61, pp.207-215. 10.1016/j.electacta.2011.12.004. hal-01539730 HAL Id: hal-01539730 https://hal.sorbonne-universite.fr/hal-01539730 Submitted on 15 Jun 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Interfacial properties of mercury/ethylammonium nitrate ionic liquid + water system: electrocapillarity, surface charge and differential capacitance Malika Ammam †‡*, Dung Di Caprio† and Laurent Gaillo† † Laboratoire d’Electrochimie et Chimie Analytique, Equipe Energétique et Réactivité aux Interfaces, Université Pierre et Marie Curie-Case 39, 4, place Jussieu 75252 PARIS Cedex 05, France ‡ Present address: Faculty of Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, ON L1H 7K4, Canada * Corresponding author: Phone (905)721-8668, ext 3625; Fax 905-721-3304; email: [email protected]; [email protected] Abstract In this account, surface tensions of mercury/ethylammonium nitrate (EAN) aqueous solutions at different compositions as a function of the potential have been measured.
    [Show full text]
  • Synthesis, Characterization and Combustion of Triazolium Based Salts U
    Synthesis, Characterization and Combustion of Triazolium Based Salts U. Schaller, T. Keicher, V. Weiser, H. Krause Fraunhofer Institut Chemische Technologie (ICT) Pfinztal, Germany S. Schlechtriem DLR – German Aerospace Center, Space Propulsion Institute Hardthausen, Germany ABSTRACT Salts being liquid below 100 °C are defined as ionic liquids[1]. They are receiving an increasing interest due to their unique properties and are also under investigation in the field of energetic materials. Potential applications are plasticizers, high explosives, gun and liquid rocket propellants. As a promising candidate for a high energy propellant, this paper presents the synthesis and some properties of 4-Amino-1-methyl-1,2,4-triazolium nitrate (AMTN). It has a glass transition point of -55 °C and shows good stability. Due to the very low vapor pressure a significantly reduced environmental risk, better storage and handling properties are expected. The combustion behavior was investigated in a window bomb under pressures up to 15 MPa resulting in a linear burning characteristic with low pressure dependence. Moreover, 4-Amino-1-methyl-1,2,4-triazolium perchlorate (AMTP) was synthesized and characterized. With its melting point close to TNT, AMTP has potential as a melt cast explosive. The enthalpy of formation was determined and the predicted performance was compared with TNT. For comparison the 4-Amino-1-H-1,2,4-triazolium salts were also synthesized. INTRODUCTION Ionic liquids (ILs) are in the focus of recent research and finding application in more and more fields of life. The applications range from novel reaction media[2], as electrolytes in batteries[3], solar cells[4], gas storing media[5], lubricants[6] and heat transfer fluids[7], to mention only a small excerpt of the investigated and in use applications.
    [Show full text]
  • Experimental Investigation of Mixtures of 1-Ethyl-3- Methylimidazolium Ethyl Sulfate and Ethylammonium Nitrate with Electrospray Propulsion Applications
    AIAA Propulsion and Energy Forum 10.2514/6.2019-3900 19-22 August 2019, Indianapolis, IN AIAA Propulsion and Energy 2019 Forum Experimental Investigation of Mixtures of 1-Ethyl-3- Methylimidazolium Ethyl sulfate and Ethylammonium Nitrate with Electrospray Propulsion Applications Mitchell J. Wainwright,1 Missouri University of Science and Technology, Rolla, Missouri, 65409 Joshua L. Rovey,2 University of Illinois Urbana-Champaign, Urbana IL, 61801 Shawn W. Miller,3 Boston College, Institute for Scientific Research, Chestnut Hill, MA, 02467 and Benjamin D. Prince,4 Air Force Research Laboratory, Space Vehicle Directorate, Kirtland AFB, NM, 87117 Physical properties, performance metrics, and mass spectra of mixtures of two ionic liquids (1-ethyl-3-methylimidazolium ethyl-sulfate aka [Emim][EtSO4] and ethylammonium nitrate aka EAN) are investigated from the standpoint of electrospray propulsive characteristics. Spectra suggest that as the [Emim][EtSO4] mixture fraction increases, the intensity of [Emim][EtSO4] related species in the plume also increases, while the presence of EAN decreases. Spectra also show presence of both EAN proton transfer species and species related to chemical reaction of [EtSO4] and water. Despite the volatility of EAN, it emits stably into vacuum at low flow rates when mixed with 25% [Emim][EtSO4]. Spectra also show species swapping between [Emim][EtSO4] and EAN, suggesting microscopic reorganization and non-linear mixing of physical properties. Experimental measurements of surface tension, conductivity, and density for various mixture mass percentages also show non-linear mixing characteristics. Conductivity differs by over 40% from linear predicted values. Analytic predictions of propulsion performance are presented based on the non- linear experimental property results, and compared to predictions based on linear mixing models.
    [Show full text]
  • Hydrogen Bonding in Protic Ionic Liquids: Structural Correlations, Vibrational Spectroscopy, and Rotational Dynamics of Liquid Ethylammonium Nitrate
    Hydrogen Bonding in Protic Ionic Liquids: Structural Correlations, Vibrational Spectroscopy, and Rotational Dynamics of Liquid Ethylammonium Nitrate Tobias Zentel1, Viviane Overbeck2, Dirk Michalik2, Oliver K¨uhn1, Ralf Ludwig2 1Institut f¨urPhysik, Universit¨atRostock, Albert-Einstein-Str. 23-24, D-18059 Rostock, Germany 2Abteilung f¨urPhysikalische Chemie, Institut f¨urChemie, Universit¨atRostock, Dr.-Lorenz-Weg 1, D-18059 Rostock, Germany E-mail: [email protected] July 26, 2017 Abstract. The properties of the hydrogen bonds in ethylammonium nitrate are analyzed by using molecular dynamics simulations and infrared as well as nuclear magnetic resonance experiments. Ethylammonium nitrate features a flexible three-dimensional network of hydrogen bonds with moderate strengths, which makes it distinct from related triethylammonium-based ionic liquids. First, the network's flexibility is manifested in a not very pronounced correlation of the hydrogen bond geometries, which is caused by rapid interchanges of bonding partners. The large flexibility of the network leads to a substantial broadening of the mid-IR absorption band, with the contributions due to N-H stretching motions ranging from 2800 to 3250 cm−1. Finally, the different dynamics are also seen in the rotational correlation of the N-H bond vector, where a correlation time as short as 16.1 ps is observed. Submitted to: J. Phys. B: At. Mol. Phys. 1. Introduction Ethylammonium nitrate (EAN) has been synthesized more than hundred years ago by Paul Walden [1]. EAN is formed by the neutralization of ethylamine with concentrated nitric acid. It consists solely of ions, namely ethylammonium and nitrate, and melts significantly below 100◦C, i.e.
    [Show full text]
  • Liquid Methylammonium Nitrate ⇑ Lorenzo Gontrani A, , Ruggero Caminiti A,B, Umme Salma A, Marco Campetella A,C a Università Degli Studi Di Roma ‘‘La Sapienza”, P
    Chemical Physics Letters 684 (2017) 304–309 Contents lists available at ScienceDirect Chemical Physics Letters journal homepage: www.elsevier.com/locate/cplett Research paper A structural and theoretical study of the alkylammonium nitrates forefather: Liquid methylammonium nitrate ⇑ Lorenzo Gontrani a, , Ruggero Caminiti a,b, Umme Salma a, Marco Campetella a,c a Università degli Studi di Roma ‘‘La Sapienza”, P. le Aldo Moro 5, I-00185 Roma, Italy b Centro di Ricerca per le Nanotecnologie Applicate all’Ingegneria CNIS, Università di Roma ‘‘La Sapienza”, P. le Aldo Moro 5, I-00185 Roma, Italy c Chimie ParisTech, PSL Research University, CNRS, Institut de Recherche de Chimie Paris, F-75005 Paris, France article info abstract Article history: We present here a structural and vibrational analysis of melted methylammonium nitrate, the simplest Received 22 May 2017 compound of the family of alkylammonium nitrates. The static and dynamical features calculated were In final form 5 July 2017 endorsed by comparing the experimental X-ray data with the theoretical ones. A reliable description can- Available online 6 July 2017 not be obtained with classical molecular dynamics owing to polarization effects. Contrariwise, the struc- ture factor and the vibrational frequencies obtained from ab initio molecular dynamics trajectories are in Keywords: very good agreement with the experiment. A careful analysis has provided additional information on the X-ray complex hydrogen bonding network that exists in this liquid. Nitrate Ó 2017 Elsevier B.V. All rights reserved. Methylammonium Melted AIMD 1. Introduction transfer reaction between the Brønsted acid nitric acid and the Brønsted base alkylamine. MAN is instead solid at room tempera- The latvian/russian/german chemist Paul Walden is generally ture, but it undergoes a solid I solid II phase transition at 352 K, recognized as one of the ‘‘fathers” of that class of (organic) molten turning into a ‘‘ionic plastic phase” which shows very large mobil- salts that most contemporary chemists would call ‘‘ionic liquids”.
    [Show full text]
  • Surfactant Behaviour of Sodium Dodecylsulfate In
    Subscriber access provided by CMU Libraries - http://library.cmich.edu Article Surfactant Behaviour of Sodium Dodecylsulfate in the Deep Eutectic Solvent Choline Chloride: Urea Thomas Arnold, Andrew J Jackson, Adrian Sanchez- Fernandez, Daniel Magnone, Ann E. Terry, and Karen J. Edler Langmuir, Just Accepted Manuscript • DOI: 10.1021/acs.langmuir.5b02596 • Publication Date (Web): 05 Nov 2015 Downloaded from http://pubs.acs.org on November 7, 2015 Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
    [Show full text]
  • Heat Capacity of Liquids: Critical Review and Recommended Values
    Heat Capacity of Liquids: Critical Review and Recommended Values. Supplement I Cite as: Journal of Physical and Chemical Reference Data 30, 1199 (2001); https:// doi.org/10.1063/1.1407866 Submitted: 20 February 2001 . Published Online: 10 January 2002 Milan Zábranský, Vlastimil Růžička, and Eugene S. Domalski ARTICLES YOU MAY BE INTERESTED IN Heat Capacity of Liquids: Critical Review and Recommended Values. Supplement II Journal of Physical and Chemical Reference Data 39, 013103 (2010); https:// doi.org/10.1063/1.3182831 Estimation of the Heat Capacities of Organic Liquids as a Function of Temperature using Group Additivity. II. Compounds of Carbon, Hydrogen, Halogens, Nitrogen, Oxygen, and Sulfur Journal of Physical and Chemical Reference Data 22, 619 (1993); https:// doi.org/10.1063/1.555924 Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III Journal of Physical and Chemical Reference Data 25, 1 (1996); https://doi.org/10.1063/1.555985 Journal of Physical and Chemical Reference Data 30, 1199 (2001); https://doi.org/10.1063/1.1407866 30, 1199 © 2002 by the U.S. Secretary of Commerce on behalf of the United States. All rights reserved. Heat Capacity of Liquids: Critical Review and Recommended Values. Supplement I Milan Za´bransky´, Vlastimil Ru˚ zˇicˇka, Jr.,a… and Eugene S. Domalskib… Department of Physical Chemistry, Institute of Chemical Technology, 166 28 Prague 6, Czech Republic ͑Received 20 February 2001; revised manuscript received 30 July 2001͒ A study was carried out in which new experimental data on heat capacities of pure liquid organic and some inorganic compounds were compiled, critically evaluated, and recommended values provided.
    [Show full text]
  • Abstract Reversed Phase Liquid Chromatography Using the Ionic Liquid Isopropylammonium Formate and Comparison of Indirect Spectr
    ABSTRACT REVERSED PHASE LIQUID CHROMATOGRAPHY USING THE IONIC LIQUID ISOPROPYLAMMONIUM FORMATE AND COMPARISON OF INDIRECT SPECTROPHOTOMETRIC METHODS FOR PHOSPHATE by Matthew P. Collins A new room temperature ionic liquid, isopropylammonium formate, IPAF, has been synthesized. Its application as a mobile phase replacement for traditional organic reversed phase-high performance liquid chromatography solvents is demonstrated. Solvent characteristics of IPAF, such as, polarity index, viscosity, and solvent strength are measured. Various van Deemter plots using different mixing approaches of the mobile phase and different columns are compared. The utility of IPAF has been further shown to be a suitable modifier solvent for the separation of cytochrome c from tryptophan. At 50°C, IPAF was able to maintain cytochrome c in its native form during the course of a chromatography separation, while a similar methanol modifier causes denaturation. Our long term goal is to develop a semi-preparative method to separate proteins in their native conformation. A comparison of atomic absorption and molecular spectrophotometry for the use in determining phosphate in an undergraduate teaching environment is also presented. REVERSED PHASE LIQUID CHROMATOGRAPHY USING THE IONIC LIQUID ISOPROPYLAMMONIUM FORMATE AND COMPARISON OF INDIRECT SPECTROPHOTOMETRIC METHODS FOR PHOSPHATE A Thesis Submitted to the Faculty of Miami University in partial fulfillment of the requirements for the degree of Master of Science Department of Chemistry and Biochemistry by Matthew
    [Show full text]
  • Aggregation Behavior of Long-Chain Piperidinium Ionic Liquids in Ethylammonium Nitrate
    Molecules 2014, 19, 20157-20169; doi:10.3390/molecules191220157 OPEN ACCESS molecules ISSN 1420-3049 www.mdpi.com/journal/molecules Article Aggregation Behavior of Long-Chain Piperidinium Ionic Liquids in Ethylammonium Nitrate Caili Dai, Mingyong Du, Yifei Liu, Shilu Wang, Jianhui Zhao, Ang Chen, Dongxu Peng and Mingwei Zhao * State Key Laboratory of Heavy Oil Processing, School of Petroleum Engineering, China University of Petroleum (Huadong), Qingdao 266580, Shandong, China; E-Mails: [email protected] (C.D.); [email protected] (M.D.); [email protected] (Y.L.); [email protected] (S.W.); [email protected] (J.Z.); [email protected] (A.C.); [email protected] (D.P.) * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +86-532-8698-1183; Fax: +86-532-8698-1161. External Editor: Derek J. McPhee Received: 13 October 2014; in revised form: 7 November 2014 / Accepted: 21 November 2014 / Published: 2 December 2014 Abstract: Micelles formed by the long-chain piperidinium ionic liquids (ILs) N-alkyl-N-methylpiperidinium bromide of general formula CnPDB (n = 12, 14, 16) in ethylammonium nitrate (EAN) were investigated through surface tension and dissipative particle dynamics (DPD) simulations. Through surface tension measurements, the critical micelle concentration (cmc), the effectiveness of surface tension reduction (Πcmc), the maximum excess surface concentration (Гmax) and the minimum area occupied per 0 surfactant molecule (Amin) can be obtained. A series of thermodynamic parameters (ΔGm, 0 0 ΔH m and ΔS m ) of micellization can be calculated and the results showed that the micellization was entropy-driven. In addition, the DPD simulation was performed to simulate the whole aggregation process behavior to better reveal the micelle formation process.
    [Show full text]
  • Secondary Aerosol from Atmospheric Aliphatic Amines
    Atmos. Chem. Phys. Discuss., 7, 289–349, 2007 Atmospheric www.atmos-chem-phys-discuss.net/7/289/2007/ Chemistry ACPD © Author(s) 2007. This work is licensed and Physics 7, 289–349, 2007 under a Creative Commons License. Discussions Secondary aerosol from atmospheric aliphatic amines S. M. Murphy et al. Secondary aerosol formation from atmospheric reactions of aliphatic amines Title Page Abstract Introduction 1 1 2 1 1 1 S. M. Murphy , A. Sorooshian , J. H. Kroll , N. L. Ng , P. Chhabra , C. Tong , Conclusions References J. D. Surratt1, E. Knipping3, R. C. Flagan1, and J. H. Seinfeld1 Tables Figures 1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA 2Current Address: Aerodyne Research Inc., Billerica, MA, USA J I 3Electric Power Research Institute, Palo Alto, CA, USA J I Received: 17 December 2006 – Accepted: 17 December 2006 – Published: 10 January 2007 Back Close Correspondence to: J. H. Seinfeld ([email protected]) Full Screen / Esc Printer-friendly Version Interactive Discussion EGU 289 Abstract ACPD Although aliphatic amines have been detected in both urban and rural atmospheric aerosols, little is known about the chemistry leading to particle formation or the poten- 7, 289–349, 2007 tial aerosol yields from reactions of gas-phase amines. We present here the first sys- 5 tematic study of aerosol formation from the atmospheric reactions of amines. Based Secondary aerosol on laboratory chamber experiments and theoretical calculations, we evaluate aerosol from atmospheric formation from reaction of OH, ozone, and nitric acid with trimethylamine, methylamine, aliphatic amines triethylamine, diethylamine, ethylamine, and ethanolamine. Entropies of formation for alkylammonium nitrate salts are estimated by molecular dynamics calculations en- S.
    [Show full text]