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Journal articles on the topic 'Maleic anhydride Reactivity'

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Author: Grafiati

Published: 10 December 2022

Last updated: 29 January 2023

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1

Escalera, Santiago de la, and Enrique Palacián. "Dimethylmaleic anhydride, a specific reagent for protein amino groups." Biochemistry and Cell Biology 67, no. 1 (January 1, 1989): 63–66. http://dx.doi.org/10.1139/o89-010.

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The reagent dimethylmaleic anhydride does not cause a stable modification of thiol compounds under the conditions used for modification of protein amino groups, in contrast to maleic and monomethylmaleic anhydrides, which produce an irreversible modification of sulfhydryl groups. This behavior and the low reactivity toward hydroxyamino acid residues, shown in a previous work, make dimethylmaleic anhydride a specific reagent for protein amino groups.Key words: sulfhydryl modification, cysteine residues, maleic anhydride, monomethylmaleic anhydride, dimethylmaleic anhydride.

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2

Gil Girol, Stefanie, Thomas Strunskus, Martin Muhler, and Christof Wöll. "Reactivity of ZnO Surfaces toward Maleic Anhydride." Journal of Physical Chemistry B 108, no. 36 (September 2004): 13736–45. http://dx.doi.org/10.1021/jp048386d.

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3

Bistac, S., M. F. Vallat, and J. Schultz. "Investigation of Chemical Interactions at the Steel/Polymer Interface by FT-IR Diffuse Reflectance Spectroscopy." Applied Spectroscopy 51, no. 12 (December 1997): 1823–25. http://dx.doi.org/10.1366/0003702971939893.

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Interactions between a steel surface and an ethylene–vinyl acetate copolymer grafted with maleic anhydride have been investigated by Fourier transform infrared (FT-IR) diffuse reflectance spectroscopy. The failed surfaces obtained after a mechanical separation of the polymer/steel assemblies have been analyzed. The results show that a new peak appears, characteristic of a carboxylate group. A model system composed of maleic anhydride deposited on iron plates has been studied in order to consider more specifically the reactivity of maleic anhydride. Peaks characteristic of metallic carboxylate complexes are present in the spectrum. A two-step mechanism has been proposed: the opening of the anhydride cycle by a hydrolysis reaction, leading to the formation of a carboxylic diacid, followed by the reaction of the acid with some oxidized metallic elements present at the metal surface. This study underlines the contribution of FT-IR reflectance techniques to the understanding of the adhesion mechanisms.

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4

Vida, Norbert, Jiří Václavík, and Petr Beier. "Synthesis and reactivity of aliphatic sulfur pentafluorides from substituted (pentafluorosulfanyl)benzenes." Beilstein Journal of Organic Chemistry 12 (January 20, 2016): 110–16. http://dx.doi.org/10.3762/bjoc.12.12.

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Oxidation of 3- and 4-pentafluorosulfanyl-substituted anisoles and phenols with hydrogen peroxide and sulfuric acid provided a mixture of SF5-substituted muconolactone, maleic, and succinic acids. A plausible mechanism for the formation of the aliphatic SF5 compounds was presented and their chemical reactivity was investigated. SF5-substituted para-benzoquinone was synthesized; its oxidation led to an improved yield of 2-(pentafluorosulfanyl)maleic acid. The reaction of SF5-substituted maleic anhydride and para-benzoquinone with cyclopentadiene afforded the Diels–Alder adducts. Decomposition of 3-(pentafluorosulfanyl)muconolactone in acidic, neutral and basic aqueous media was investigated and the decarboxylation of 2-(pentafluorosulfanyl)maleic acid provided 3-(pentafluorosulfanyl)acrylic acid.

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5

Shaik, Muneer, Vamshi K. Chidara, Srinivas Abbina, and Guodong Du. "Zinc Amido-Oxazolinate Catalyzed Ring Opening Copolymerization and Terpolymerization of Maleic Anhydride and Epoxides." Molecules 25, no. 18 (September 4, 2020): 4044. http://dx.doi.org/10.3390/molecules25184044.

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Ring opening copolymerization (ROCOP) of epoxides and cyclic anhydrides has become an attractive approach for the synthesis of biodegradable polyesters with various compositions. Encouraged by the efficiency and versatility of a series of amido-oxazolinate zinc complexes, in this study they were shown to be active catalysts for the synthesis of unsaturated polyesters via ROCOP of maleic anhydride and various epoxides. The relative activity of epoxides in these reactions was observed to be styrene oxide > cyclohexene oxide > phenyl glycidyl ether, which could be correlated with the electronic and steric features of the substrate. To provide more structural possibilities for the polyesters, the difference in epoxide reactivity was exploited in an attempt to prepare block terpolymers from one anhydride and two epoxides. Terpolymerization was carried out in one or two steps in a single pot. The thermal characterization by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques suggested that the resulting materials were mostly random terpolymers.

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6

Fellows, Christopher M., and Ernest Senogles. "The reactivity of maleic anhydride toward the 1-phenylethyl radical." European Polymer Journal 34, no. 9 (September 1998): 1249–54. http://dx.doi.org/10.1016/s0014-3057(97)00262-0.

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7

Spino, Claude, and Jason Crawford. "2-Carbomethoxy-1,3-butadiene: an electronically activated diene in [4 + 2] cycloadditions with electron-deficient dienophiles." Canadian Journal of Chemistry 71, no. 7 (July 1, 1993): 1094–97. http://dx.doi.org/10.1139/v93-145.

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Cross Diels–Alder reactions between 2-carbomethoxy-1,3-butadiene 1 and electron-rich dienes were carried out. It was found that diene 1 had a higher reactivity than even the well-known Danishefsky diene in its Diels–Alder cycloaddition with electron-deficient dienophiles. In addition, (Z)-1-methylthio-3-carbomethoxy-1,3-butadiene 11 was found to have a higher reactivity than (Z)-1-methylthio-1,3-butadiene and (Z)-2-carbomethoxy-1,3-hexadiene, while both (E)- and (Z)-1,2-(bis)-carbomethoxy-1,3-butadiene 14 reacted efficiently with maleic anhydride to give the corresponding cy-cloadduct 15.

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8

McIntyre, Hannah M., and Megan L. Hart. "Immobilization of TiO2 Nanoparticles in Cement for Improved Photocatalytic Reactivity and Treatment of Organic Pollutants." Catalysts 11, no. 8 (August 1, 2021): 938. http://dx.doi.org/10.3390/catal11080938.

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Non-point organic pollutants in stormwater are a growing problem in the urban environment which lack effective and efficient treatment technologies. Incorporation of conventional wastewater techniques within stormwater management practices could fundamentally change how stormwater quality is managed because contaminants can be degraded during stormwater transport or storage. This study investigated the photocatalytic reactivity of titanium dioxide functionalized with maleic anhydride (Ti-MAH) within cement pastes when compared to ordinary Portland cement. Preparation of Ti-MAH was performed by permanently bonding maleic anhydride to titanium in methanol, drying and powdering the residual material, and then inter-grinding the preparation with cement during mixing. When compared with OPC, the Ti-MAH cured cement paste is more reactive under a wider range of light wavelengths, possesses a higher band gap, sustains this heightened reactivity over multiple testing iterations, and treats organics effectively (>95% methylene blue removal). Amorphous silica within calcium-silica-hydrate, C-S-H, is theorized to bond to the powdered Ti-MAH during curing. Verification of silicon bonding to the titanium by way of MAH was demonstrated by FTIR spectra, SEM imagery, and XRD. Creating a sustainable and passive photocatalytic cement that precisely bonds silica to Ti-MAH is useful for organic contaminants in urban stormwater, but use can translate to other applications because Ti-MAH bonds readily with any amorphous silica such as glass materials, paints and coatings, optics, and LEDS, among many others.

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9

Cavani, F., S. Ligi, T. Monti, F. Pierelli, F. Trifirò, S. Albonetti, and G. Mazzoni. "Relationship between structural/surface characteristics and reactivity in n-butane oxidation to maleic anhydride." Catalysis Today 61, no. 1-4 (August 2000): 203–10. http://dx.doi.org/10.1016/s0920-5861(00)00383-7.

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10

Medrán, Noelia S., Federico Dezotti, and Silvina C. Pellegrinet. "Remarkable Reactivity of Boron-Substituted Furans in the Diels–Alder Reactions with Maleic Anhydride." Organic Letters 21, no. 13 (June 19, 2019): 5068–72. http://dx.doi.org/10.1021/acs.orglett.9b01662.

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11

Sanmathi, C. S., S. Prasannakumar, and B. S. Sherigara. "Terpolymerization of 2-ethoxy ethylmethacrylate, styrene and maleic anhydride: determination of the reactivity ratios." Bulletin of Materials Science 27, no. 3 (June 2004): 243–49. http://dx.doi.org/10.1007/bf02708513.

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12

Samyn, Pieter, and Vibhore K. Rastogi. "Stabilization of an Aqueous Bio-Based Wax Nano-Emulsion through Encapsulation." Nanomaterials 12, no. 23 (December 6, 2022): 4329. http://dx.doi.org/10.3390/nano12234329.

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The emulsification of biowaxes in an aqueous environment is important to broaden their application range and make them suitable for incorporation in water-based systems. The study here presented proposes a method for emulsification of carnauba wax by an in-situ imidization reaction of ammonolysed styrene (maleic anhydride), resulting in the encapsulation of the wax into stabilized organic nanoparticles. A parameter study is presented on the influences of wax concentrations (30 to 80 wt.-%) and variation in reaction conditions (degree of imidization) on the stability and morphology of the nanoparticles. Similar studies are done for encapsulation and emulsification of paraffin wax as a reference material. An analytical analysis with Raman spectroscopy and infrared spectroscopy indicated different reactivity of the waxes towards encapsulation, with the bio-based carnauba wax showing better compatibility with the formation of imidized styrene (maleic anhydride) nanoparticles. The latter can be ascribed to the higher functionality of the carnauba wax inducing more interactions with the organic nanoparticle phase compared to paraffin wax. In parallel, the thermal and mechanical stability of nanoparticles with encapsulated carnauba wax is higher than paraffin wax, as studied by differential scanning calorimetry, thermogravimetric analysis and dynamic mechanical analysis. In conclusion, a stable aqueous emulsion with a maximum of 70 wt.-% encapsulated carnauba wax was obtained, being distributed as a droplet phase in 200 nm organic nanoparticles.

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13

Vargas, M. A., N. N. López, M. J. Cruz, F. Calderas, and O. Manero. "Viscoelasticity of Asphalts Modified with SEBS Copolymers Functionalized with Various Amounts of Maleic Anhydride." Rubber Chemistry and Technology 82, no. 2 (May 1, 2009): 244–70. http://dx.doi.org/10.5254/1.3548248.

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Abstract It is known that the microstructure of polymer-modified asphalts (PMA) depends strongly of the characteristics of the polymer. The modifier polymer improves the mechanical properties of pure asphalt when used in paved roads. In this work, asphalt is modified using reactive polymers obtained via functionalization of styrene-ethylene/butylene-styrene (SEBS) copolymers in solution using various amounts of benzoil peroxide (BPO) as initiator and maleic anhydride (MAH). The resulting functionalized copolymer (SEBS-g-MAH) with variable amounts of grafting (variable reactivity) is blended with the asphalt at small contents (2–4 wt. %). The amount of MAH grafting was determined by FTIR, 1HNMR, GPC, DSC and by titration with KOH, and this amount is readily correlated with the improvement of the mechanical properties and thermal stability of the asphalt. In addition, the limit of the polymer-asphalt compatibility is determined for these systems.

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14

Pasquale, Anthony J., and Timothy E. Long. "Determination of monomer reactivity ratios usingin situ FTIR spectroscopy for maleic anhydride/norbornene-free-radical copolymerization." Journal of Applied Polymer Science 92, no. 5 (2004): 3240–46. http://dx.doi.org/10.1002/app.20355.

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15

Wu, Chang-Mou, Ri-Ichi Murakami, Syuan-Guang Lai, Po-Chun Lin, Pankaj Koinkar, Kuei-Chi Lee, Chiu-Chun Lai, and Syang-Peng Rwei. "Investigation on the interface modification of PET/PP composites." Modern Physics Letters B 33, no. 14n15 (May 28, 2019): 1940019. http://dx.doi.org/10.1142/s0217984919400190.

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In this study, surface modifications and manufacturing processes for polyethylene terephthalate (PET)/polypropylene (PP) composites were developed. When non-polar PP resin is combined with polar polyester fiber, its compatibility and wettability are the key technologies. Maleic anhydride-grafted PP (MAPP) was blended with PP to improve the polarity of the PP resin and react with PET fibers. In addition, a primer was applied to the PET fabric to improve the bonding and reactivity of PET fiber and MAPP. PET/PP composites that imitated the texture and appearance of carbon fabric were prepared by thin film stacking method. The effect of MAPP and primer on interfacial bonding was evaluated by single-fiber pullout test. The mechanical properties of the PET/PP composites such as impact, and open-hole tensile strength (OHT), were studied.

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16

Smirnov, A. I., T. L. Petrova, G. V. Ratovskii, O. A. Shivernovskaya, A. V. Kalabina, and V. P. Zubov. "Relationship between the conformational structure of vinylaryl ethers and their reactivity in alternating copolymerization with maleic anhydride." Polymer Science U.S.S.R. 30, no. 4 (January 1988): 800–809. http://dx.doi.org/10.1016/0032-3950(88)90192-x.

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17

Bauduin, Gerard, Bernard Boutevin, and Fouad Malek. "Copolymerization of chloromethylstyrene and maleic anhydride: an example for testing a new method to determine reactivity ratios." European Polymer Journal 28, no. 10 (October 1992): 1237–39. http://dx.doi.org/10.1016/0014-3057(92)90211-j.

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18

Kirshanov, Kirill, Roman Toms, Pavel Melnikov, and Alexander Gervald. "Unsaturated Polyester Resin Nanocomposites Based on Post-Consumer Polyethylene Terephthalate." Polymers 14, no. 8 (April 14, 2022): 1602. http://dx.doi.org/10.3390/polym14081602.

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A method for producing nanocomposites of unsaturated polyester resins (UPR) based on recycled polyethylene terephthalate (PET) as a matrix has been proposed. The upcycling method involves three successive stages: (1) oligoesters synthesis, (2) simultaneous glycolysis and interchain exchange of oligoesters with PET, (3) interaction of the obtained resins with glycol and maleic anhydride. UPRs were characterized by FTIR spectroscopy and gel permeation chromatography. The mechanical properties of nanocomposites obtained on the basis of these resins and titanium dioxide have been investigated. It has been shown that 1,2-propylene glycol units, despite their lower reactivity, significantly improve the properties of UPR. The most promising nanocomposite sample exhibited tensile strength 112.62 MPa, elongation at break 157.94%, and Young’s modulus 29.95 MPa. These results indicate that the proposed method made it possible to obtain nanocomposites with high mechanical properties based on recycled PET thus allowing one to create a valuable product from waste.

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19

Belalia, Mahmoud, Meriem Bendjelloul, Abdallah Aziz, and El Hadj Elandaloussi. "Surface Modification of Olive Stone Waste for Enhanced Sorption Properties of Cadmium and Lead Ions." Acta Chemica Iasi 26, no. 2 (December 1, 2018): 281–306. http://dx.doi.org/10.2478/achi-2018-0018.

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Abstract This paper reports the synthesis and characterization of an efficient anionic olive stone waste-based material as new ion-exchanger adsorbent. The olive stone waste was subjected to an alkaline pretreatment in order to enhance their reactivity towards maleic anhydride. The maleate-derived material MOS was characterized by FTIR, 13C NMR, TGA and DSC. The resulting sodium form of material NaMOS was subjected to batch experiments in order to evaluate its cadmium and lead removal efficiency. Adsorption experimental data showed a uniform and rapid process. Both Langmuir and Freundlich isotherm models were found to fit adequately the equilibrium isotherm data. The sorption capacities reached 240.96 mg Cd g−1 and 127.38 mg Pb g−1. The thermodynamic parameters showed that the process was exothermic and the adsorption occurred spontaneously. The desorption experiments show a quantitative recovery of the metal ions from NaMOS material.

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20

Janes, Dustin W., Michael J. Maher, Gregory T. Carroll, David M. Saylor, and Christopher J. Ellison. "Modulating Solubility and Enhancing Reactivity of Photo-Cross-Linkable Poly(styrene sulfonyl azide-alt-maleic anhydride) Thin Films." Macromolecules 48, no. 22 (November 3, 2015): 8361–68. http://dx.doi.org/10.1021/acs.macromol.5b01875.

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21

Florjańczyk *, Zbigniew, Włodzimierz Krawiec, and Katarzyna Such. "A study of the relative reactivity of maleic anhydride and some maleimides in free radical copolymerization and terpolymerization." Journal of Polymer Science Part A: Polymer Chemistry 28, no. 4 (March 1990): 795–801. http://dx.doi.org/10.1002/pola.1990.080280408.

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22

Nifant’ev, Ilya, Alexander Vinogradov, Alexey Vinogradov, and Pavel Ivchenko. "DFT Modeling of the Alternating Radical Copolymerization and Alder-Ene Reaction between Maleic Anhydride and Olefins." Polymers 12, no. 4 (March 27, 2020): 744. http://dx.doi.org/10.3390/polym12040744.

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The free radical copolymerization of electron-acceptor and electron-donor vinyl monomers represents a particular case of sequence-controlled polymerization. The reactions of maleic anhydride (MA) or related compounds (acceptor comonomers) with α-olefins (donor comonomers) result in the formation of the alternating copolymers that have clear prospects for petrochemical and biomedical applications. However, in contrast to the well-established polymerization of acrylate monomers, these processes have not been studied theoretically using the density functional theory (DFT) calculations. In our research, we performed a comprehensive theoretical analysis of the free radical copolymerization of MA and closely related maleimide with different structural types of olefins at mpw1pw91/6-311g(d) level of the DFT. The results of our calculations clearly indicated the preference of the alternating reaction mode for the copolymerization of MA with α-olefins, isobutylene and prospective unsaturated monomers, as well as methylenealkanes. The DFT modeling of the thermally induced Alder-ene reaction between MA and olefins allowed to exclude this reaction from the scope of possible side processes at moderately high temperatures. Comparative analysis of MA and N-methylmaleimide (MMI) reactivity shown that the use of MMI instead of MA makes no sense in terms of the reaction rate and selectivity.

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23

Jursic, Branko S. "AM1 semiempirical study of benzopyrroles as dienes for Diels-Alder reaction." Canadian Journal of Chemistry 74, no. 1 (January 1, 1996): 114–20. http://dx.doi.org/10.1139/v96-015.

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A qualitative approach for quick evaluation of the reactivity of dienes such as cyclopentadiene, furan, pyrrole, indole, and isoindole for Diels–Alder reactions was applied. As qualitative methods, the frontier molecular orbital (FMO) energy gap and the Hammond postulate through bond orders and energy of the reaction were evaluated for such dienophiles as ethylene, 1,3-dioxa-4-cyclopentene, and maleic anhydride. It was demonstrated that pyrrole and benzopyrroles are poor dienes in comparison with cyclopentadiene and furan. Because the reaction is controlled by the HOMO of the diene there are special cases when isoindole can react as a diene, while the loss of indole aromaticity in the course of the reaction precludes the cycloaddition. Geometries of transition structures and the accompanying activation energies were calculated for pyrrole, indole, and isoindole as dienes. The stereoselectivity of the reaction is discussed and compared with experimental results. Key words: benzopyrroles as dienes, Diels–Alder cycloaddition, Hammond postulate.

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24

Ghorbani, Maryam, Zahra Asghari Aghmashhadi, Seyed Mojtaba Amininasab, and Raoufeh Abedini. "Effect of different coupling agents on the thermal, mechanical and biological behavior of vinyl acetate-wood polymer composite." Holzforschung 73, no. 10 (August 27, 2019): 967–73. http://dx.doi.org/10.1515/hf-2018-0175.

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AbstractPoplar wood (Populus deltoidesBartr.) was modified by a combined two-step treatment with different chemicals to improve its properties. Maleic anhydride (MAN), 3-(trimethoxysilyl) propyl methacrylate (TMPS) and glycidyl methacrylate (GMA) were first employed to modify wood cell wall resulting in WMAN, WTMPSand WGMA. Then, in a second step, the vinyl acetate (VA) monomer was let to polymerize within the cell lumina resulting in WPCMAN/VA, WPCTMPS/VAand WPCGMA/VA(WPCs). Field emission scanning electron microscopy (FESEM) observations confirmed the bulking of modified cell walls. The thermal stability, mechanical properties and decay resistance of WPCs were remarkably improved compared to unmodified wood in the order WPCGMA/VA > WPCTMPS/VA > WPCMAN/VA. WPCMAN/VAdisplayed a significant decay resistance increment, despite lower retention and reactivity than the WPCTMPS/VA, which is probably due to a better penetration into the cell wall and the higher degree of chemical modification of the wood components.

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25

Cavani, Fabrizio, Davide De Santi, Silvia Luciani, Axel Löfberg, Elisabeth Bordes-Richard, Carlotta Cortelli, and Roberto Leanza. "Transient reactivity of vanadyl pyrophosphate, the catalyst for n-butane oxidation to maleic anhydride, in response to in-situ treatments." Applied Catalysis A: General 376, no. 1-2 (March 31, 2010): 66–75. http://dx.doi.org/10.1016/j.apcata.2009.10.037.

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26

Petrova, T. L., A. I. Smirnova, G. V. Ratovskii, V. B. Mantsivoda, and V. P. Zubov. "Influence of the structure of the donor acceptor complex of vinylbenzyl ether with maleic anhydride on reactivity in alternating copolymerization." Polymer Science U.S.S.R. 28, no. 12 (January 1986): 2905–12. http://dx.doi.org/10.1016/0032-3950(86)90169-3.

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27

Zerroukhi, A., C. Cincu, and J. P. Montheard. "Substituted styrenes-maleic anhydride copolymers?Measurements of the reactivity ratios with high conversions and relations between molecular masses and viscosity." Journal of Applied Polymer Science 71, no. 9 (February 28, 1999): 1447–54. http://dx.doi.org/10.1002/(sici)1097-4628(19990228)71:9<1447::aid-app9>3.0.co;2-w.

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28

Klumperman, Bert, and Gea Vonk. "Solvent effects on the copolymerization of styrene with maleic anhydride: determination of apparent reactivity ratios from the penultimate unit model." European Polymer Journal 30, no. 8 (August 1994): 955–60. http://dx.doi.org/10.1016/0014-3057(94)90030-2.

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29

Yu, Yang, Xiu Lan Xin, Ya Na Wei, Hong Qin Liu, and Shao Xiang Yang. "Synthesis and Property of Water-Soluble Hyperbranched Polyacrylate Emulsion." Applied Mechanics and Materials 262 (December 2012): 460–63. http://dx.doi.org/10.4028/www.scientific.net/amm.262.460.

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Hyperbranched polymer is a kind of non-linear polymers with highly branched structure and a lot of terminal groups. It has many advantages, such as high reactivity, good solubility and low viscosity. Hyperbranched polymer has become a focus in modern scientific domain. In this paper, polyester-type water-soluble hyperbranched monomer is prepared by the ring-opening polymerization reaction of maleic anhydride with polyol. Hyperbranched polyacrylate emulsion with 70-110nm was synthesized by emulsion polymerization using methyl methacrylate (MMA), butyl acrylate (BA), acrylic acid (AA) and hyperbranched polymer as comonomer. The effects of dosages and adding order of monomers, concentration of initator, type and amount of chain transfer agent on the polymerization are discussed. The as-prepared emusions were analyzed by FTIR, DSC, SEM. The solid content, particle size, stability of emulsion and morphology and water absorption of film were measured. The results showed that hyperbranched polyacrylate emulsion had low viscosity, high stability and can form very flat and smooth film. Hyperbranched polyacrylate emulsion can be widely applied in modern ink industry for its low cost,simple process and stable quality.

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30

Borisevich, Sophia S., Alena V. Kovalskaya, Inna P. Tsypysheva, and Sergey L. Khursan. "Thermodynamically controlled Diels–Alder reaction of 12-N-methylcytisine: A DFT study." Journal of Theoretical and Computational Chemistry 13, no. 06 (September 2014): 1450048. http://dx.doi.org/10.1142/s0219633614500485.

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A DFT study was performed for the Diels–Alder traction of 12-N-methylcytisine with a number of dienophiles (in boiling toluene under atmospheric pressure), namely, N-phenylmaleimide, maleic anhydride, 2,4-benzoquinone, tetracyanoethylene and methyl methacrylate. It was shown that 12-N-methylcytisine selectively reacts with these dienophiles, only the reaction with N-phenylmaleimide (NPM) resulting in the formation of thermodynamically stable adducts, which is consistent with experimental data. This selectivity of 12-N-methylcytisine is attributable to the difference between the properties of the listed dienophiles, which is confirmed by the relative reactivity indices calculated within the framework of the frontier molecular orbital (FMO) and hard and soft (Lewis) acids and bases (HSAB) theories, the thermodynamic and activation parameters of the forward and retro-Diels–Alder reactions. According to analysis of the theoretical results, NPM is characterized by high chemical potential, hardness close to that of 12-N-methylcytisine, and commensurable heights of the activation barriers for the forward and reverse Diels–Alder reactions and also forms stable [4+2] adducts.

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31

AMANO, Maho, Haruko OGAWA, Kyoko KOJIMA, Tomoko KAMIDAIRA, Susumu SUETSUGU, Munehiro YOSHIHAMA, Takanori SATOH, Tatsuya SAMEJIMA, and Isamu MATSUMOTO. "Identification of the major allergens in wheat flour responsible for baker's asthma." Biochemical Journal 330, no. 3 (March 15, 1998): 1229–34. http://dx.doi.org/10.1042/bj3301229.

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Baker's asthma, a typical occupational allergic disease, is a serious problem in the food industries. In this study, purification and identification of major allergens recognized by IgEs in sera of allergic patients were performed. Major immunoreactive proteins were purified from the albumin fraction by gel filtration on a Toyopearl HW-50 column followed by reverse-phase HPLC. The N-terminal amino acid sequences and molecular masses measured by MS indicated that the major immunoreactive proteins are members of the α-amylase inhibitor family, 0.19 and 0.28. Significant leukotriene release by each purified protein was observed in cell-associated stimulation tests, suggesting in vivo activity of these antigens. Carbohydrate analyses of major allergens indicated that they are monoglycosylated but not N-glycosylated in spite of the presence of a potential N-glycosylation site. Recombinant 0.19 expressed in Escherichia coli showed the same reactivity with IgE as native wheat 0.19 in Western blotting and ELISA using methyl vinyl ether maleic anhydride co-polymer as an immobilizing reagent, suggesting that the allergenic epitopes are located in the peptide portions.

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32

Fujimori, Kiyohisa. "Rate of copolymerization of maleic anhydride with butyl vinyl ether in CHCl3 and relative reactivity of free monomers and the complex." Polymer Bulletin 13, no. 5 (May 1985): 459–62. http://dx.doi.org/10.1007/bf01033345.

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33

Mouat, Asher P., Clare Paton-Walsh, Jack B. Simmons, Jhonathan Ramirez-Gamboa, David W. T. Griffith, and Jennifer Kaiser. "Measurement report: Observations of long-lived volatile organic compounds from the 2019–2020 Australian wildfires during the COALA campaign." Atmospheric Chemistry and Physics 22, no. 17 (August 31, 2022): 11033–47. http://dx.doi.org/10.5194/acp-22-11033-2022.

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Abstract. In 2019–2020, Australia experienced its largest wildfire season on record. Smoke covered hundreds of square kilometers across the southeastern coast and reached the site of the COALA-2020 (Characterizing Organics and Aerosol Loading over Australia) field campaign in New South Wales. Using a subset of nighttime observations made by a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS), we calculate emission ratios (ERs) and factors (EFs) for 15 volatile organic compounds (VOCs). We restrict our analysis to VOCs with sufficiently long lifetimes to be minimally impacted by oxidation over the ∼ 8 h between when the smoke was emitted and when it arrived at the field site. We use oxidized VOC to VOC ratios to assess the total amount of radical oxidation: maleic anhydride / furan to assess OH oxidation, and (cis-2-butenediol + furanone) / furan to assess NO3 oxidation. We examine time series of O3 and NO2 given their closely linked chemistry with wildfire plumes and observe their trends during the smoke event. Then we compare ERs calculated from the freshest portion of the plume to ERs calculated using the entire nighttime period. Finding good agreement between the two, we are able to extend our analysis to VOCs measured in more chemically aged portions of the plume. Our analysis provides ERs and EFs for six compounds not previously reported for temperate forests in Australia: acrolein (a compound with significant health impacts), methyl propanoate, methyl methacrylate, maleic anhydride, benzaldehyde, and creosol. We compare our results with two studies in similar Australian biomes, and two studies focused on US temperate forests. We find over half of our EFs are within a factor of 2.5 relative to those presented in Australian biome studies, with nearly all within a factor of 5, indicating reasonable agreement. For US-focused studies, we find similar results with over half our EFs within a factor of 2.5, and nearly all within a factor of 5, again indicating reasonably good agreement. This suggests that comprehensive field measurements of biomass burning VOC emissions in other regions may be applicable to Australian temperate forests. Finally, we quantify the magnitude attributable to the primary compounds contributing to OH reactivity from this plume, finding results comparable to several US-based wildfire and laboratory studies.

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Sergi, Claudia, Francesca Sbardella, Matteo Lilli, Jacopo Tirillò, Andrea Calzolari, and Fabrizio Sarasini. "Hybrid Cellulose–Basalt Polypropylene Composites with Enhanced Compatibility: The Role of Coupling Agent." Molecules 25, no. 19 (September 24, 2020): 4384. http://dx.doi.org/10.3390/molecules25194384.

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This study deals with the development and optimization of hybrid composites integrating microcrystalline cellulose and short basalt fibers in a polypropylene (PP) matrix to maximize the mechanical properties of resulting composites. To this aim, the effects of two different coupling agents, endowed with maleic anhydride (MA-g(grafted)-PP) and acrylic acid (AA-g-PP) functionalities, on the composite properties were investigated as a function of their amount. Tensile, flexural, impact and heat deflection temperature tests highlighted the lower reactivity and effectiveness of AA-g-PP, regardless of reinforcement type. Hybrid formulations with basalt/cellulose (15/15) and with 5 wt. % of MA-g-PP displayed remarkable increases in tensile strength and modulus, flexural strength and modulus, and notched Charpy impact strength, of 45% and 284%, 97% and 263%, and 13%, in comparison with neat PP, respectively. At the same time, the thermo-mechanical stability was enhanced by 65% compared to neat PP. The results of this study, if compared with the ones available in the literature, reveal the ability of such a combination of reinforcements to provide materials suitable for automotive applications with environmental benefits.

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Ma, Jun, Chong Cheng, and Karen L. Wooley. "The Power of RAFT for Creating Polymers Having Imbedded Side-Chain Functionalities: Norbornenyl-Functionalized Polymers and their Transformations via ROMP and Thiol-ene Reactions." Australian Journal of Chemistry 62, no. 11 (2009): 1507. http://dx.doi.org/10.1071/ch09243.

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Robust, efficient and orthogonal chemistries are becoming increasingly important tools for the construction of increasingly sophisticated materials. In this article, the selectivity of reversible addition–fragmentation chain transfer (RAFT)-based radical polymerization of bifunctional monomers is exploited for the preparation of statistical and block copolymers that contain imbedded side-chain functionalities, which are then shown to exhibit two different orthogonal types of chemical reactivity to afford discrete nanoscale objects and functional derivative structures. Based on the radical reactivity ratios calculated from Alfrey–Price theory, a bifunctional monomer 4-(5′-norbornene-2′-methoxy)-2,3,5,6-tetrafluorostyrene (1) was designed and synthesized, for its highly reactive tetrafluorostyrenyl group relative to its norbornene (Nb) group. Selective RAFT copolymerization of 1 with styrene (St) afforded copolymers with over 50 mol-% structural units having a pendent norbornenyl functionality while maintaining narrow molecular weight distribution (polydispersity index (PDI) = 1.23). Diblock copolymers (PDI = 1.09–1.23) with Nb side-chain substituents regioselectively placed along one segment of the block copolymer structure were also prepared by RAFT copolymerizations of 1 with St or 2,3,4,5,6-pentafluorostyrene, using either polystyrene or poly(styrene-alt-maleic anhydride)-based macro chain-transfer agents. A well-defined star block copolymer (PDI = 1.23) having a poly(norbornene)-based core and polystyrene arms was obtained by ring-opening metathesis polymerization using the regioselective diblock copolymer PSt-b-P(1-co-St) as the multifunctional macromonomer and Grubbs’ catalyst (first generation) as the initiator. Photo-induced thiol-ene reactions of Nb-functionalized polymers with thiols were fast and efficient, yielding polymers with new side-chain structures.

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Burgada, Francisco, Eduardo Fages, Luis Quiles-Carrillo, Diego Lascano, Juan Ivorra-Martinez, Marina P. Arrieta, and Octavio Fenollar. "Upgrading Recycled Polypropylene from Textile Wastes in Wood Plastic Composites with Short Hemp Fiber." Polymers 13, no. 8 (April 12, 2021): 1248. http://dx.doi.org/10.3390/polym13081248.

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This research reports the manufacturing and characterization of green composites made from recycled polypropylene obtained from the remnants of polypropylene non-woven fabrics used in the textile industry and further reinforced with short hemp fibers (SHFs). To improve the interaction of the reinforcing fibers with the recycled polymeric matrix, two types of compatibilizing agents (maleic anhydride grafted, PP-g-MA, and maleinized linseed oil, MLO) were added during melt-processing, the percentage of which had to remain constant concerning the amount of fiber loading to ensure complete reactivity. Standardized test specimens were obtained by injection molding. The composites were characterized by mechanical (tensile, impact, and hardness), thermal (DSC, TGA), thermomechanical, FTIR, and FESEM microscopy tests. In addition, color and water uptake properties were also analyzed. The results show that the addition of PP-g-MA to rPP was satisfactory, thus improving the fiber-matrix interaction, resulting in a marked reinforcing effect of the hemp fibers in the recycled PP matrix, which can be reflected in the increased stiffness of the samples. In parallel to the compatibilizing effect, a plasticizing effect was obtained by incorporating MLO, causing a decrease in the glass transition temperature of the composites by approximately 6 °C and an increase in ductility compared to the unfilled recycled polypropylene samples.

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Druzhinina, A. V., M. Sh Suleimenova, O. A. Almabekov, and A. K. Kusainova. "SYNTHESIS OF POLYIMIDES OF ARILACYCLIC STRUCTURE." Chemical Journal of Kazakhstan 74, no. 2 (June 30, 2021): 124–32. http://dx.doi.org/10.51580/2021-1/2710-1185.34.

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The article describes methods for producing polymeric materials based on tetra-carboxylic acid dianhydrides obtained by photochemical or solar irradiation from furan and maleic anhydride. The procedure of synthesis of aryl-alicyclic polyimides based on 7-оxsоdiciklo (2,2,1)-gepten -2,3- dicarboxylic acid(MAF) and diaminodiphenyl oxide diamines (DADFO) and dioxytriphenyldiamine (DOTFDA) in polar aprotic amide-type solvents has been studied in detail in the presence of a basic catalyst type: trimethyl-amine.The nature and reactivity of staring monomers affect the process of obtaining polyimides. The optimal conditions for obtaining polyimides with intrinsic viscosity values of 1.30-1.64 dl/g have been found. Physicochemical, electrical and thermal proper-ties of the synthesized polyimides have been investigated. It was found that they have increased elasticity, high tensile strength. Elongation at break of polyimide films reaches 30-43%, tensile strength is 130-180 MPa. According to their electrical properties, these polyimides are classified as medium-frequency dielectrics. In addition, they differ in thermoplasticity in the range from 210 ºС to 250 ºС, have thermal stability and do not decompose at heating in air to temperatures of 335-390 ºС, and the presence of oxide groups in the structure of polymers increases the solubility of polyimides.

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Fujimori, Kiyohisa, Phillip P. Organ, Marion J. Costigan, and Ian E. Craven. "Relative Reactivity of Free Monomers and Donor-Acceptor Complex in Alternating Copolymerization of Isobutyl Vinyl Ether with Maleic Anhydride from the Rate of Polymerization." Journal of Macromolecular Science: Part A - Chemistry 23, no. 5 (May 1986): 647–55. http://dx.doi.org/10.1080/00222338608058502.

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Cavani, F., C. Cortelli, A. Frattini, G. Puccinotti, M. Ricotta, F. Rodeghiero, F. Trifirò, C. Fumagalli, and G. Mazzoni. "The dilution of vanadyl pyrophosphate, catalyst for n-butane oxidation to maleic anhydride, with aluminum phosphate: unexpected reactivity due to the contribution of the diluting agent." Topics in Catalysis 38, no. 4 (August 2006): 295–301. http://dx.doi.org/10.1007/s11244-006-0028-3.

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Cavani, Fabrizio, Silvia Luciani, Elisa Degli Esposti, Carlotta Cortelli, and Roberto Leanza. "Surface Dynamics of A Vanadyl Pyrophosphate Catalyst forn-Butane Oxidation to Maleic Anhydride: An In Situ Raman and Reactivity Study of the Effect of the P/V Atomic Ratio." Chemistry - A European Journal 16, no. 5 (February 1, 2010): 1646–55. http://dx.doi.org/10.1002/chem.200902017.

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Gültner, Marén, Regine Boldt, Petr Formanek, Dieter Fischer, Frank Simon, and Petra Pötschke. "The Localization Behavior of Different CNTs in PC/SAN Blends Containing a Reactive Component." Molecules 26, no. 5 (March 1, 2021): 1312. http://dx.doi.org/10.3390/molecules26051312.

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Co-continuous blend systems of polycarbonate (PC), poly(styrene-co-acrylonitrile) (SAN), commercial non-functionalized multi-walled carbon nanotubes (MWCNTs) or various types of commercial and laboratory functionalized single-walled carbon nanotubes (SWCNTs), and a reactive component (RC, N-phenylmaleimide styrene maleic anhydride copolymer) were melt compounded in one step in a microcompounder. The blend system is immiscible, while the RC is miscible with SAN and contains maleic anhydride groups that have the potential to reactively couple with functional groups on the surface of the nanotubes. The influence of the RC on the localization of MWCNTs and SWCNTs (0.5 wt.%) was investigated by transmission electron microscopy (TEM) and energy-filtered TEM. In PC/SAN blends without RC, MWCNTs are localized in the PC component. In contrast, in PC/SAN-RC, the MWCNTs localize in the SAN-RC component, depending on the RC concentration. By adjusting the MWCNT/RC ratio, the localization of the MWCNTs can be tuned. The SWCNTs behave differently compared to the MWCNTs in PC/SAN-RC blends and their localization occurs either only in the PC or in both blend components, depending on the type of the SWCNTs. CNT defect concentration and surface functionalities seem to be responsible for the localization differences.

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Tansiri, Vanalee, and Pranut Potiyaraj. "Compatibilization Efficiency of Reactively Modified Poly(butylene succinate) as a Compatibilizer for Poly(butylene succinate) Composites." Advanced Materials Research 1119 (July 2015): 288–91. http://dx.doi.org/10.4028/www.scientific.net/amr.1119.288.

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The modified poly (butylene succinate) (PBS), namely, PBS-g-MA and PBS-g-GMA were prepared in order to be used as a compatibilizer for PBS composites. The grafting of maleic anhydride (MA) or glycidyl methacrylate (GMA) onto PBS was carried out using a twin-screw extruder. The grafting reactions were confirmed by spectroscopic analysis. Comparing with MA, it was found that GMA can be effectively grafted on PBS. The PBS-g-GMA was successfully used for PBS composites to enhance thermal properties. Furthermore, it was found that the incorporation of compatibilizer increased the melt viscosity of PBS composites.

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Cui, Yong-Yan, Bao-Jian Dong, Bao-Long Li, and Shu-Cai Li. "Properties of Polypropylene/Poly(ethylene terephthalate) Thermostimulative Shape Memory Blends Reactively Compatibilized by Maleic Anhydride Grafted Polyethylene-Octene Elastomer." International Journal of Polymeric Materials 62, no. 13 (June 28, 2013): 671–77. http://dx.doi.org/10.1080/00914037.2013.769225.

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44

Saputra, Ozi Adi, Ludfiaastu Rinawati, Kartika Setia Rini, Dheo Adha Saputra, and Edi Pramono. "Effect of Fiber Size on Mechanical and Water Absorption Properties of Recycled Polypropylene/Empty Fruit Bunches (rPP/EFB) Bio-Composites." Applied Mechanics and Materials 842 (June 2016): 7–13. http://dx.doi.org/10.4028/www.scientific.net/amm.842.7.

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The influence of fiber size on mechanical and water absorption properties of recycled Polypropylene/Palm Empty Fruit Bunch (namely, rPP/EFB) bio-composites has been conducted study. rPP/EFB bio-composite was a compounding of recycled polypropylene (rPP) and palm empty fruit bunch (EFB) with different sizes, i.e. particle size (150 mesh sieve escaped, referred as p-EFB) and short fiber (s-EFB). Manufacturing of the bio-composites was prepared by the solution method in boiling xylene via reactively process using benzoyl peroxide as an initiator. The addition of coupling agent, such as maleic anhydride grafted polypropylene (PP-g-MAH) was improve the chemical interaction between the rPP and EFB which evidenced by the shift of the wave number of raw materials on infra-red spectra of rPP/EFB bio-composite. Mechanical properties test showed that s-EFB was increase the tensile strength value up to 95% compare to rPP, higher than the p-EFB which is 56% compare to rPP. However, the elongation percentage of the bio-composites contain s-EFB was lower than the bio-composites contain p-EFB. Water absorption analysis also performed in this study to determine the biodegradability of bio-composites. In this study, fiber size gives a considerable influence on the mechanical properties of rPP/EFB bio-composites, however not significant on water absorption properties.

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Bott, Simon G., Kaiyuan Yang, Kathleen A. Talafuse, and Michael G. Richmond. "Phosphine Ligand Attack at Both the Methylidyne Cap and the CpNi Center in HCCo2NiCp(CO)6by 2,3-Bis(diphenylphosphino)maleic Anhydride (bma): P−C Bond Cleavage Reactivity, Kinetics, and X-ray Structures of the Zwitterionic Clusters Co2NiCp(CO)4(μ-CO)[μ2,η2,η1-C(H)PPh2CC(PPh2)C(O)OC(O)] and Co2NiCp(CO)4[μ2,η2,σ-C(H)PPh2CCC(O)OC(O)](μ2-PPh2)." Organometallics 22, no. 7 (March 2003): 1383–90. http://dx.doi.org/10.1021/om0209273.

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Bott, Simon G., Kaiyuan Yang, and Michael G. Richmond. "Unusual chemical reactivity in the reactions of Re2(CO)8(μ-H)(μ-η1,η2-CHCHBu) with 2,3-bis(diphenylphosphino)maleic anhydride (bma) and Re2(CO)8(bma) with Ni(cod)2: X-ray diffraction structures of Re2(CO)8(bma), zwitterionic Re(CO)4[Re(CO)4(bma)], and the phosphido-bridged complex Re2(CO)8[μ-η1,η1-(O)](μ-PPh2)." Journal of Organometallic Chemistry 689, no. 4 (February 2004): 791–800. http://dx.doi.org/10.1016/j.jorganchem.2003.10.043.

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Yang, Kaiyuan, Jeffery A. Martin, Simon G. Bott, and Michael G. Richmond. "Diyne and Phosphorus−Carbon Bond Reactivity in the Reaction between [Co2(CO)6]2(PhC4Ph) and 2,3-Bis(diphenylphosphino)maleic Anhydride (bma). Syntheses, Molecular Orbital Properties, and X-ray Diffraction Structures of Co2(CO)4[μ-η2:η2:η1:η1-(Z)-Ph2P(Ph)CC(PhC2)- CC(Ph2P)C(O)OC(O)], Co2(CO)2(bma)2·CH2Cl2, and Co2(CO)2(bma)[μ-CC(Ph2P)C(O)OC(O)](μ2-Ph2P)·C6H14." Organometallics 15, no. 9 (January 1996): 2227–36. http://dx.doi.org/10.1021/om950988j.

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48

Bignardi, G., F. Cavani, C. Cortelli, T. De Lucia, F. Pierelli, F. Trifirò, G. Mazzoni, C. Fumagalli, and T. Monti. "Influence of the oxidation state of vanadium on the reactivity of V/P/O, catalyst for the oxidation of n-pentane to maleic and phthalic anhydrides." Journal of Molecular Catalysis A: Chemical 244, no. 1-2 (February 2006): 244–51. http://dx.doi.org/10.1016/j.molcata.2005.09.010.

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Gaglieri, Caroline, Rafael Alarcon, Aniele de Moura, Raquel Magri, Daniel Rinaldo, and Gilbert Bannach. "Effect of Isomerization and Copolymerization of Itaconic Anhydride During the Synthesis of Renewable Monomers Using Vegetable Oils." Journal of the Brazilian Chemical Society, 2023. http://dx.doi.org/10.21577/0103-5053.20220134.

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Vegetable oils are alternatives to producing renewable monomers since they are biomass. It is possible to react them with anhydrides by heating to provide monomers with high reactivity. However, after the reaction of grape seed oil with itaconic anhydride, it was observed the occurrence of parallel reactions that had not been observed when the same oil was reacted with maleic anhydride. Some articles in the literature have reported that temperature and bases can isomerize itaconic anhydride into citraconic anhydride, which is more stable at room temperature. However, they have not focused on completely understanding how this phenomenon occurred nor studied it in processes that involve microwave irradiation. Therefore, this paper presents a complete characterization and investigation about the thermal behavior of itaconic anhydride and how it can affect the monomer synthesis performed under heating.

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Widstrom, Andrea L., and Benjamin J. Lear. "Structural and solvent control over activation parameters for a pair of retro Diels-Alder reactions." Scientific Reports 9, no. 1 (December 2019). http://dx.doi.org/10.1038/s41598-019-54156-4.

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AbstractWe report the temperature dependent NMR of two Diels-Alder adducts of furan: one formed with maleic anhydride and the other with N-methylmaleimide. These adducts are the products of so-called ‘click’ reactions, widely valued for providing simple, reliable, and robust reactivity. Under our experimental conditions, these adducts undergo a retro Diels-Alder reaction and we use our temperature dependent NMR to determine the rates of these reactions at multiple temperatures—ultimately providing estimates of the activation parameters for the reversion. We repeat these measurements in three solvents. We find that, in all solvents, the barrier to reversion is larger for the adduct formed with N-methylmaleimide. The barrier to reversion for this adduct is relatively insensitive to changes in solvent while the adduct formed with maleic anhydride responds more strongly to changes in solvent polarity. The differences in reaction barrier and solvent dependence arises because the adduct formed with N-methylmalemide is more stable—leading to a larger barrier to reversion—while the adduct formed with maleic anhydride experiences a larger change in dipole during the reaction—leading to a larger solvent dependence.

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