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Wendels S, Chavez T, Bonnet M, Salmeia KA, Gaan S. Recent Developments in Organophosphorus Flame Retardants Containing P-C Bond and Their Applications. MATERIALS (BASEL, SWITZERLAND) 2017; 10:E784. [PMID: 28773147 PMCID: PMC5551827 DOI: 10.3390/ma10070784] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Revised: 06/17/2017] [Accepted: 07/04/2017] [Indexed: 01/05/2023]
Abstract
Organophosphorus compounds containing P-C bonds are increasingly developed as flame retardant additives due to their excellent thermal and hydrolytic stability and ease of synthesis. The latest development (since 2010) in organophosphorus flame retardants containing P-C bonds summarized in this review. In this review, we have broadly classified such phosphorus compounds based on the carbon unit linked to the phosphorus atom i.e., could be a part of either an aliphatic or an aromatic unit. We have only considered those published literature where a P-C bond was created as a part of synthetic strategy to make either an intermediate or a final organophosphorus compound with an aim to use it as a flame retardant. General synthetic strategies to create P-C bonds are briefly discussed. Most popular synthetic strategies used for developing P-C containing phosphorus based flame retardants include Michael addition, Michaelis-Arbuzov, Friedels-Crafts and Grignard reactions. In general, most flame retardant derivatives discussed in this review have been prepared via a one- to two-step synthetic strategy with relatively high yields greater than 80%. Specific examples of P-C containing flame retardants synthesized via suitable synthetic strategy and their applications on various polymer systems are described in detail. Aliphatic phosphorus compounds being liquids or low melting solids are generally applied in polymers via coatings (cellulose) or are incorporated in the bulk of the polymers (epoxy, polyurethanes) during their polymerization as reactive or non-reactive additives. Substituents on the P atoms and the chemistry of the polymer matrix greatly influence the flame retardant behavior of these compounds (condensed phase vs. the gas phase). Recently, aromatic DOPO based phosphinate flame retardants have been developed with relatively higher thermal stabilities (>250 °C). Such compounds have potential as flame retardants for high temperature processable polymers such as polyesters and polyamides. A vast variety of P-C bond containing efficient flame retardants are being developed; however, further work in terms of their economical synthetic methods, detailed impact on mechanical properties and processability, long term durability and their toxicity and environmental impact is much needed for their potential commercial exploitations.
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Affiliation(s)
- Sophie Wendels
- Additives and Chemistry Group, Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland.
| | - Thiebault Chavez
- Additives and Chemistry Group, Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland.
| | - Martin Bonnet
- Additives and Chemistry Group, Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland.
| | - Khalifah A Salmeia
- Additives and Chemistry Group, Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland.
| | - Sabyasachi Gaan
- Additives and Chemistry Group, Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland.
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52
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Sztáray B, Voronova K, Torma KG, Covert KJ, Bodi A, Hemberger P, Gerber T, Osborn DL. CRF-PEPICO: Double velocity map imaging photoelectron photoion coincidence spectroscopy for reaction kinetics studies. J Chem Phys 2017; 147:013944. [DOI: 10.1063/1.4984304] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Bálint Sztáray
- Department of Chemistry, University of the Pacific, Stockton, California 95211, USA
| | - Krisztina Voronova
- Department of Chemistry, University of the Pacific, Stockton, California 95211, USA
| | - Krisztián G. Torma
- Department of Chemistry, University of the Pacific, Stockton, California 95211, USA
| | - Kyle J. Covert
- Department of Chemistry, University of the Pacific, Stockton, California 95211, USA
| | - Andras Bodi
- Laboratory for Femtochemistry and Synchrotron Radiation, Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Patrick Hemberger
- Laboratory for Femtochemistry and Synchrotron Radiation, Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Thomas Gerber
- Laboratory for Femtochemistry and Synchrotron Radiation, Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - David L. Osborn
- Combustion Research Facility, Sandia National Laboratories, Livermore, California 94551, USA
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53
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Understanding the mechanism of catalytic fast pyrolysis by unveiling reactive intermediates in heterogeneous catalysis. Nat Commun 2017; 8:15946. [PMID: 28660882 PMCID: PMC5493764 DOI: 10.1038/ncomms15946] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 05/08/2017] [Indexed: 12/27/2022] Open
Abstract
Catalytic fast pyrolysis is a promising way to convert lignin into fine chemicals and fuels, but current approaches lack selectivity and yield unsatisfactory conversion. Understanding the pyrolysis reaction mechanism at the molecular level may help to make this sustainable process more economic. Reactive intermediates are responsible for product branching and hold the key to unveiling these mechanisms, but are notoriously difficult to detect isomer-selectively. Here, we investigate the catalytic pyrolysis of guaiacol, a lignin model compound, using photoelectron photoion coincidence spectroscopy with synchrotron radiation, which allows for isomer-selective detection of reactive intermediates. In combination with ambient pressure pyrolysis, we identify fulvenone as the central reactive intermediate, generated by catalytic demethylation to catechol and subsequent dehydration. The fulvenone ketene is responsible for the phenol formation. This technique may open unique opportunities for isomer-resolved probing in catalysis, and holds the potential for achieving a mechanistic understanding of complex, real-life catalytic processes. The conversion of lignin by catalytic fast pyrolysis into useful fine chemicals is a promising route to fuel production, however selectivity and conversion are still not optimal. Here, the authors investigate the reaction mechanism by detection of reactive intermediates responsible for the formation of key products.
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54
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55
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Chen Z, Jiang M, Zhang Q, Yu Y, Sun G, Jiang J. Synergistic effect of combined dimethyl methylphosphonate with aluminum hydroxide or ammonium polyphosphate retardant systems on the flame retardancy and thermal properties of unsaturated polyester resin. INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION 2017. [DOI: 10.1080/1023666x.2017.1331393] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Zhiquan Chen
- College of Safety Science and Engineering, Nanjing Tech University, Nanjing, China
| | - Mengwei Jiang
- College of Safety Science and Engineering, Nanjing Tech University, Nanjing, China
| | - Qingwu Zhang
- College of Safety Science and Engineering, Nanjing Tech University, Nanjing, China
| | - Yuan Yu
- Jiangsu Key Laboratory of Hazardous Chemicals Safety and Control, Nanjing Tech University, Nanjing, China
| | - Guangping Sun
- College of Safety Science and Engineering, Nanjing Tech University, Nanjing, China
| | - Juncheng Jiang
- Jiangsu Key Laboratory of Hazardous Chemicals Safety and Control, Nanjing Tech University, Nanjing, China
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56
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Ash T, Debnath T, Ghosh A, Das AK. Mechanistic Insight into the Molecular TiO2-Mediated Gas Phase Detoxication of DMMP: A Theoretical Approach. Chem Res Toxicol 2017; 30:1177-1187. [DOI: 10.1021/acs.chemrestox.7b00019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tamalika Ash
- Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032, India
| | - Tanay Debnath
- Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032, India
| | - Avik Ghosh
- Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032, India
| | - Abhijit Kumar Das
- Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032, India
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57
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Liang S, Hemberger P, Levalois‐Grützmacher J, Grützmacher H, Gaan S. Probing Phosphorus Nitride (P≡N) and Other Elusive Species Formed upon Pyrolysis of Dimethyl Phosphoramidate. Chemistry 2017; 23:5595-5601. [DOI: 10.1002/chem.201700402] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Indexed: 11/05/2022]
Affiliation(s)
- Shuyu Liang
- Laboratory of Inorganic Chemistry ETH Zürich, Swiss Federal Institute of Technology Vladimir-Prelog-Weg 1-5/10 8093 Zürich Switzerland
- Additives and Chemistry, Advanced Fibers Empa, Swiss Federal Laboratories for Materials Science Lerchenfeldstrasse 5 9014 St. Gallen Switzerland
| | - Patrick Hemberger
- Laboratory for Femtochemistry and Synchrotron Radiation Paul Scherrer Institute WSLA/115 5232 Villigen-PSI Switzerland
| | - Joëlle Levalois‐Grützmacher
- Laboratory of Inorganic Chemistry ETH Zürich, Swiss Federal Institute of Technology Vladimir-Prelog-Weg 1-5/10 8093 Zürich Switzerland
| | - Hansjörg Grützmacher
- Laboratory of Inorganic Chemistry ETH Zürich, Swiss Federal Institute of Technology Vladimir-Prelog-Weg 1-5/10 8093 Zürich Switzerland
| | - Sabyasachi Gaan
- Additives and Chemistry, Advanced Fibers Empa, Swiss Federal Laboratories for Materials Science Lerchenfeldstrasse 5 9014 St. Gallen Switzerland
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58
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Wu X, Zhou X, Hemberger P, Bodi A. Dissociative Photoionization of Dimethyl Carbonate: The More It Is Cut, the Bigger the Fragment Ion. J Phys Chem A 2017; 121:2748-2759. [DOI: 10.1021/acs.jpca.7b00544] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiangkun Wu
- Hefei
National Laboratory for Physical Sciences at the Microscale and Department
of Chemical Physics, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, China
| | - Xiaoguo Zhou
- Hefei
National Laboratory for Physical Sciences at the Microscale and Department
of Chemical Physics, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, China
| | - Patrick Hemberger
- Laboratory
for Femtochemistry and Synchrotron Radiation, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - Andras Bodi
- Laboratory
for Femtochemistry and Synchrotron Radiation, Paul Scherrer Institute, 5232 Villigen, Switzerland
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59
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Bodi A, Sigurdardottir KL, Kvaran Á, Bjornsson R, Arnason I. Dissociative Photoionization of 1-Halogenated Silacyclohexanes: Silicon Traps the Halogen. J Phys Chem A 2016; 120:9188-9197. [DOI: 10.1021/acs.jpca.6b09195] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andras Bodi
- Laboratory
for Femtochemistry and Synchrotron Radiation, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | | | - Ágúst Kvaran
- Science
Institute, University of Iceland, Dunhaga 3, 107 Reykjavík, Iceland
| | - Ragnar Bjornsson
- Science
Institute, University of Iceland, Dunhaga 3, 107 Reykjavík, Iceland
| | - Ingvar Arnason
- Science
Institute, University of Iceland, Dunhaga 3, 107 Reykjavík, Iceland
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60
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Ash T, Debnath T, Banu T, Das AK. Exploration of Unimolecular Gas-Phase Detoxication Pathways of Sarin and Soman: A Computational Study from the Perspective of Reaction Energetics and Kinetics. Chem Res Toxicol 2016; 29:1439-57. [DOI: 10.1021/acs.chemrestox.6b00132] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tamalika Ash
- Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032, India
| | - Tanay Debnath
- Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032, India
| | - Tahamida Banu
- Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032, India
| | - Abhijit Kumar Das
- Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032, India
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61
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Gibson KD, Sibener SJ. Scattering Dynamics, Survival, and Dispersal of Dimethyl Methylphosphonate Interacting with the Surface of Multilayer Graphene. J Phys Chem A 2016; 120:4863-71. [PMID: 26895563 DOI: 10.1021/acs.jpca.5b12419] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We explored the interaction of a molecular beam of dimethyl methylphosphonate with a multilayer graphene surface to better understand the fate of chemical warfare agents in the environment. The experiments were done at surface temperatures between 120 and 900 K and translational energies between 200 and 1500 meV. At the lowest temperatures, the dimethyl methylphosphonate is adsorbed, with the molecules next to the carbon surface held slightly more strongly than the bulk molecular film that grows with continued dosing. We measured the desorption energy for submonolayer coverage using modulated beam techniques and found a value of 290 meV (28 kJ/mol). At higher surface temperatures, where the residence times are very short, we measured the scattering of the dimethyl methylphosphonate as a function of angle and translational kinetic energy. For a surface temperature of 250 K, with translational kinetic energies between 200 and 1500 meV, much of the incident flux has nearly been accommodated by the surface temperature and has no memory of the incident momentum. The internal energy also seems to be at least partially accommodated. As the surface temperature increases, the scattering transitions to direct-inelastic reflection, where much of the incident translational energy is retained, and the intensity of the scattering peaks superspecularly toward glancing final angles. These results demonstrate the efficacy of using kinetic energy controlled molecular beams to probe the interactions of complex organic molecules with well-defined surfaces, extending our fundamental understanding of how the dynamics for such systems crossover from trapping-desorption to direct inelastic scattering. Moreover, these results indicate that simulations that model the dispersal of chemical warfare agents using common interfaces in the environment need to account for multiple bounce trajectories and survival of the impinging molecules.
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Affiliation(s)
- K D Gibson
- The James Franck Institute and Department of Chemistry, The University of Chicago , 929 East 57th Street, Chicago, Illinois 60637, United States
| | - S J Sibener
- The James Franck Institute and Department of Chemistry, The University of Chicago , 929 East 57th Street, Chicago, Illinois 60637, United States
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62
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Heringa MF, Slowik JG, Prévôt ASH, Baltensperger U, Hemberger P, Bodi A. Dissociative Ionization Mechanism and Appearance Energies in Adipic Acid Revealed by Imaging Photoelectron Photoion Coincidence, Selective Deuteration, and Calculations. J Phys Chem A 2016; 120:3397-405. [DOI: 10.1021/acs.jpca.6b00908] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Maarten F. Heringa
- Laboratory
of Atmospheric Chemistry, Paul Scherrer Institute, Villigen PSI, Switzerland
- Laboratory
for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute, Villigen
PSI, Switzerland
| | - Jay G. Slowik
- Laboratory
of Atmospheric Chemistry, Paul Scherrer Institute, Villigen PSI, Switzerland
| | - André S. H. Prévôt
- Laboratory
of Atmospheric Chemistry, Paul Scherrer Institute, Villigen PSI, Switzerland
| | - Urs Baltensperger
- Laboratory
of Atmospheric Chemistry, Paul Scherrer Institute, Villigen PSI, Switzerland
| | - Patrick Hemberger
- Laboratory
for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute, Villigen
PSI, Switzerland
| | - Andras Bodi
- Laboratory
for Synchrotron Radiation and Femtochemistry, Paul Scherrer Institute, Villigen
PSI, Switzerland
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63
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Head AR, Tsyshevsky R, Trotochaud L, Eichhorn B, Kuklja MM, Bluhm H. Electron Spectroscopy and Computational Studies of Dimethyl Methylphosphonate. J Phys Chem A 2016; 120:1985-91. [DOI: 10.1021/acs.jpca.6b01098] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ashley R. Head
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | | | - Lena Trotochaud
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | | | | | - Hendrik Bluhm
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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64
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Holzmeier F, Wagner I, Fischer I, Bodi A, Hemberger P. Pyrolysis of 3-Methoxypyridine. Detection and Characterization of the Pyrrolyl Radical by Threshold Photoelectron Spectroscopy. J Phys Chem A 2016; 120:4702-10. [DOI: 10.1021/acs.jpca.5b10743] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Fabian Holzmeier
- Institute
of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland D-97074, Germany
| | - Isabella Wagner
- Institute
of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland D-97074, Germany
| | - Ingo Fischer
- Institute
of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland D-97074, Germany
| | - Andras Bodi
- Molecular
Dynamics Group, Paul Scherrer Institut, CH-5232 Villigen
PSI, Switzerland
| | - Patrick Hemberger
- Molecular
Dynamics Group, Paul Scherrer Institut, CH-5232 Villigen
PSI, Switzerland
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65
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Holzmeier F, Fischer I, Kiendl B, Krueger A, Bodi A, Hemberger P. On the absolute photoionization cross section and dissociative photoionization of cyclopropenylidene. Phys Chem Chem Phys 2016; 18:9240-7. [DOI: 10.1039/c6cp01068g] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the determination of the absolute photoionization cross section of cyclopropenylidene, c-C3H2, and the heat of formation of the C3H radical and ion derived by the dissociative ionization of the carbene.
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Affiliation(s)
- Fabian Holzmeier
- Institute of Physical and Theoretical Chemistry
- University of Würzburg
- D-97074 Würzburg
- Germany
| | - Ingo Fischer
- Institute of Physical and Theoretical Chemistry
- University of Würzburg
- D-97074 Würzburg
- Germany
| | - Benjamin Kiendl
- Institute of Organic Chemistry
- University of Würzburg
- D-97074 Würzburg
- Germany
| | - Anke Krueger
- Institute of Organic Chemistry
- University of Würzburg
- D-97074 Würzburg
- Germany
| | - Andras Bodi
- Paul Scherrer Institut
- CH-5232 Villigen PSI
- Switzerland
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66
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Soller BS, Salzinger S, Rieger B. Rare Earth Metal-Mediated Precision Polymerization of Vinylphosphonates and Conjugated Nitrogen-Containing Vinyl Monomers. Chem Rev 2015; 116:1993-2022. [DOI: 10.1021/acs.chemrev.5b00313] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Benedikt S. Soller
- WACKER-Lehrstuhl
für Makromolekulare Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching bei München, Germany
| | - Stephan Salzinger
- Advanced Materials & Systems Research, BASF SE, GME/D-B001, 67056 Ludwigshafen am Rhein, Germany
| | - Bernhard Rieger
- WACKER-Lehrstuhl
für Makromolekulare Chemie, Technische Universität München, Lichtenbergstraße 4, 85748 Garching bei München, Germany
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67
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Hemberger P, da Silva G, Trevitt AJ, Gerber T, Bodi A. Are the three hydroxyphenyl radical isomers created equal?--The role of the phenoxy radical. Phys Chem Chem Phys 2015; 17:30076-83. [PMID: 26500055 DOI: 10.1039/c5cp05346c] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have investigated the thermal decomposition of the three hydroxyphenyl radicals (˙C6H4OH) in a heated microtubular reactor. Intermediates and products were identified isomer-selectively applying photoion mass-selected threshold photoelectron spectroscopy with vacuum ultraviolet synchrotron radiation. Similarly to the phenoxy radical (C6H5-O˙), hydroxyphenyl decomposition yields cyclopentadienyl (c-C5H5) radicals in a decarbonylation reaction at elevated temperatures. This finding suggests that all hydroxyphenyl isomers first rearrange to form phenoxy species, which subsequently decarbonylate, a mechanism which we also investigate computationally. Meta- and para-radicals were selectively produced and spectroscopically detectable, whereas the ortho isomer could not be traced due to its fast rethermalization and rapid decomposition in the reactor. A smaller barrier to isomerization to phenoxy was found to be the reason for this observation. Since hydroxyphenyl species may be present under typical sooting conditions in flames, the resonantly stabilized cyclopentadienyl radical adds to the hydrocarbon pool and can contribute to the formation of polycyclic aromatic hydrocarbons, which are precursors in soot formation.
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Affiliation(s)
- P Hemberger
- Molecular Dynamics Group, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland.
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68
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Voronova K, Mozaffari Easter CM, Covert KJ, Bodi A, Hemberger P, Sztáray B. Dissociative Photoionization of Diethyl Ether. J Phys Chem A 2015; 119:10654-63. [DOI: 10.1021/acs.jpca.5b08091] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Krisztina Voronova
- Department
of Chemistry, University of the Pacific, Stockton, California 95211, United States
| | | | - Kyle J. Covert
- Department
of Chemistry, University of the Pacific, Stockton, California 95211, United States
| | - Andras Bodi
- Molecular
Dynamics Group, Paul Scherrer Institut, Villigen 5232, Switzerland
| | - Patrick Hemberger
- Molecular
Dynamics Group, Paul Scherrer Institut, Villigen 5232, Switzerland
| | - Bálint Sztáray
- Department
of Chemistry, University of the Pacific, Stockton, California 95211, United States
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69
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Bouwman J, Bodi A, Oomens J, Hemberger P. On the formation of cyclopentadiene in the C3H5˙ + C2H2 reaction. Phys Chem Chem Phys 2015; 17:20508-14. [PMID: 26086435 DOI: 10.1039/c5cp02243f] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction between the allyl radical (C3H5˙) and acetylene (C2H2) in a heated microtubular reactor has been studied at the VUV beamline of the Swiss Light Source. The reaction products are sampled from the reactor and identified by their photoion mass-selected threshold photoelectron spectra (ms-TPES) by means of imaging photoelectron photoion coincidence spectroscopy. Cyclopentadiene is identified as the sole reaction product by comparison of the measured photoelectron spectrum with that of cyclopentadiene. With the help of quantum-chemical computations of the C5H7 potential energy surface, the C2H2 + C3H5˙ association reaction is confirmed to be the rate determining step, after which H-elimination to form C5H6 is prompt in the absence of re-thermalization at low pressures. The formation of cyclopentadiene as the sole product from the allyl + acetylene reaction offers a direct path to the formation of cyclic hydrocarbons under combustion relevant conditions. Subsequent reactions of cyclopentadiene may lead to the formation of the smallest polycyclic aromatic molecule, naphthalene.
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Affiliation(s)
- Jordy Bouwman
- Radboud University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7c, NL-6525 ED Nijmegen, The Netherlands.
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70
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Liu Y, He J, Yang R. Effects of Dimethyl Methylphosphonate, Aluminum Hydroxide, Ammonium Polyphosphate, and Expandable Graphite on the Flame Retardancy and Thermal Properties of Polyisocyanurate–Polyurethane Foams. Ind Eng Chem Res 2015. [DOI: 10.1021/acs.iecr.5b01019] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yanlin Liu
- National Laboratory of Flame
Retardant Materials, School of Materials, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District,
Beijing 100081, P. R. China
| | - Jiyu He
- National Laboratory of Flame
Retardant Materials, School of Materials, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District,
Beijing 100081, P. R. China
| | - Rongjie Yang
- National Laboratory of Flame
Retardant Materials, School of Materials, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District,
Beijing 100081, P. R. China
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71
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An Overview of Mode of Action and Analytical Methods for Evaluation of Gas Phase Activities of Flame Retardants. Polymers (Basel) 2015. [DOI: 10.3390/polym7030504] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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72
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Jimenez M, Lesaffre N, Bellayer S, Dupretz R, Vandenbossche M, Duquesne S, Bourbigot S. Novel flame retardant flexible polyurethane foam: plasma induced graft-polymerization of phosphonates. RSC Adv 2015. [DOI: 10.1039/c5ra08289g] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Flame retardancy of flexible polyurethane foams has become an issue due to very severe regulations.
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Affiliation(s)
- Maude Jimenez
- UMET-ISP-R2FIRE
- UMR 8207
- 59652 Villeneuve d'Ascq cedex
- France
| | | | | | - Renaud Dupretz
- UMET-ISP-R2FIRE
- UMR 8207
- 59652 Villeneuve d'Ascq cedex
- France
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