- Cross-linked polybenzimidazole with enhanced stability for high temperature proton exchange membrane fuel cells
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Cross-linked polybenzimidazole membranes were obtained by heating at 160 °C, using 4,4′-diglycidyl(3,3′,5,5′-tetramethylbiphenyl) epoxy resin (TMBP) as the cross-linker. The cross-linking reaction temperature was determined by DSC and the successful completion of the cross-linking reaction was shown by FTIR and solubility tests. The cross-linked membranes showed high proton conductivity and strong mechanical properties, as well as low swelling after immersion in 85% phosphoric acid at 90 °C. For instance, the membrane with a cross-linker content weight percent of 20% (PBI-TMBP 20%) with a PA doping level of 4.1 exhibited a proton conductivity of 0.010 S cm -1 and a low swelling volume of 50%. Moreover, the cross-linked membranes showed excellent oxidative stability. The PBI-TMBP 20% cross-linked membrane tested in Fenton's reagent (3% H2O2 solution, 4 ppm Fe2+, 70 °C) kept its shape for more than 480 h and did not break. In particular, the proton conductivity of the PA-PBI-TMBP 20% membrane after Fenton's test (30% H2O2, 20 ppm Fe2+, 85 °C) remained at a high level of 0.009 S cm-1. This investigation proved that cross-linking is a very effective approach for improving the performance of proton exchange membranes. The Royal Society of Chemistry.
- Han, Miaomiao,Zhang, Gang,Liu, Zhongguo,Wang, Shuang,Li, Mingyu,Zhu, Jing,Li, Hongtao,Zhang, Yang,Lew, Christopher M.,Na, Hui
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Read Online
- Epoxy compound, composition, material for semiconductor package, molded product, electrical and electronic device, and semiconductor package
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Epoxy compounds, compositions, materials for semiconductor packages, molded products, electrical and electronic devices, and semiconductor packages are provided. The epoxy compound is represented by the following Chemical Formula 1 and has at least one mesogenic naphthalene unit. In Chemical Formula 1, at least one of M1, M2, or M3, which is a mesogenic unit, is a naphthalene unit. M1, M2, M3, L1, L2, and E1 and E2 are as defined in the detailed description. The chemical formula (1) is E1-M1-L1-M2-L2-M3-E2.
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Paragraph 0308-0312
(2021/05/15)
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- Liquid crystal epoxy photosensitive resin and preparation method thereof
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The invention discloses a liquid crystal epoxy photosensitive resin and a preparation method thereof. A mesogen-containing element and an end portion with - OH were formed. Epichlorohydrin and catalyst mix, access N2 The protective solution is reacted 40 - 100 °C to give a solution A. NaOH To Solution A, the reaction-generated water was removed, the reaction 0.1 - 4 hours was continued to remove NaCl, and the resulting filtrate was filtered to remove excess EHC to give a solution B. The solution B was mixed with a methanol/acetone solution, cooled and crystallized, and the resulting crystals were washed with methanol and suction filtered. Is dried to give a liquid crystalline epoxy photosensitive resin. The liquid crystal epoxy photosensitive resin provided by the invention has the advantages of orderly liquid crystal ordering and network crosslinking, so that the liquid crystal epoxy resin has excellent light, electrical performance and better thermo-mechanical performance.
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- METHOD FOR PRODUCING EPOXY COMPOUND AND CATALYST COMPOSITION FOR EPOXIDATION REACTION
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A method of producing an epoxy compound, which comprises reacting hydrogen peroxide with a compound having a carbon-carbon double bond, in the presence of at least one of a tungsten compound and a molybdenum compound; and an onium salt comprising 20 or more carbon atoms and one or more of substituents convertible to a functional group containing an active hydrogen or a salt thereof.
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Paragraph 0399; 0400; 0401; 0402; 0403; 0404; 0405
(2015/02/18)
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- The method for producing the epoxy compound
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PROBLEM TO BE SOLVED: To provide a process for producing an alicyclic epoxy compound using hydrogen peroxide, which efficiently gives polyfunctional epoxy resins, to provide a curable resin composition containing an epoxy resin obtained by the production process for the epoxy resins, and to provide cured products thereof. SOLUTION: There is provided the epoxidation method including an oxidizing reaction of carbon-carbon double bonds using hydrogen peroxide, in which at least two kinds of tungstic acids, phosphoric acid (or a phosphate), a quaternary ammonium salt having ≥16 carbon atoms in total, and an aqueous hydrogen peroxide solution are essentially used. COPYRIGHT: (C)2011,JPOandINPIT
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Paragraph 0085-0086
(2018/07/03)
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- PROCESS FOR PRODUCING EPOXY COMPOUND
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According to the present, invention, a process for producing an epoxy compound, where an epoxy compound can be selectively produced from olefins with good yield at low cost in a safe manner by a simple operation under mild conditions without using a quaternary ammonium salt or a metal compound, is provided. The present invention relates to a process for producing an epoxy compound, comprising epoxidizing a carbon-carbon double bond of an organic compound having a carbon-carbon double bond by using hydrogen peroxide as an oxidant, wherein the epoxidation is carried by out using an organic nitrile compound and an organic amine compound.
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Page/Page column 6-7
(2012/02/06)
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- Dermal penetration and metabolism of five glycidyl ethers in human, rat and mouse skin
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1. Glycidyl ethers (GE), an important class of industrial chemicals, are considered to be potentially mutagenic in vivo because some GE have been shown to be direct mutagens in short-term in vitro tests. 2. The percutaneous penetration and metabolism of representatives of different classes of GE was studied in the fresh, full-thickness C3H mouse, and dermatomed human and Fisher 344 rat skin to determine th apparent permeability constants, lag times and metabolic profiles. 3. Five different GE, the diglycidyl ethers of bisphenol A (BADGE), 4,4'-dihydroxy-3,3',5,5'-tetramethylbiphenyl (Epikote YX4000) and 1,6-hexanediol (HDDGE) and the GE of 1-dodecanol (C12GE) and o-cresol (o-CGE), were synthesized by reaction of their alcohols with epichlorohydrin. Their radiolabelled analogues were synthesized with a 14C-label using [U-14C]-epichlorohydrin. 4. There was a large variation (four orders of magnitude) in percutaneous penetration between the five GE. In general, penetration through full-thickness mouse skin was higher than through dermatomed rat skin, whereas dermatomed human skin was the least permeable. The permeability increased in the order YX4000 12GE 12GE and o-CGE penetrated the skin unchanged. For o-CGE, but none of the other GE, the percentage of the applied dose that penetrated the skin unchanged increased over time. 7. The large variation in response observed with the five selected GE indicates that GE should not be considered as a single class of compounds but rather on the basis of their individual properties.
- Boogaard,Denneman,Van Sittert
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p. 469 - 483
(2007/10/03)
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- Metabolic inactivation of five glycidyl ethers in lung and liver of humans, rats and mice in vitro
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1. Some glycidyl ethers (GE) have been shown to be direct mutagens in short-term in vitro tests and consequently GE are considered to be potentially mutagenic in vivo. However, GE may be metabolically inactivated in the body by two different enzymatic routes: conjugation of the epoxide moiety with the endogenous tripeptide glutathione (GSH) catalysed by glutathione S-transferase (GST) or hydrolysis of the epoxide moiety catalysed by epoxide hydrolase (EH). 2. The metabolic inactivation of five different GE, the diglycidyl ethers of bisphenol A (BADGE), 4,4'-dihydroxy-3,3',5,5'-tetramethylbiphenyl (Epikote YX4000) and 1,6-hexanediol (HDDGE) and the GE of 1-dodecanol (C12GE) and o-cresol (o-CGE), has been studied in subcellular fractions of human, C3H mouse and F344 rat liver and lung. 3. All GE were chemically very stable and resistant to aqueous hydrolysis, but were rapidly hydrolysed by EH in cytosolic and microsomal fractions of liver and lung. The aromatic GE were very good substrates for EH. In general, microsomal EH is more efficient than cytosolic EH in hydrolysis of GE, and human microsomes are more efficient than rodent microsomes. 4. The more water-soluble GE, o-CGE and HDDGE, were good substrates for GST whereas the more lipophilic GE, YX4000 and C12GE, were poor substrates for GST. In general, rodents are more efficient in GSH conjugation of GE than humans. 5. In general, the epoxide groups of YX4000 are the most and those of HDDGE the least efficiently inactivated of the five GE under study. For the other three GE no general trend was observed: the relative efficiency of inactivation varied with organ and species. 6. The large variation in metabolism observed with five representative GE indicate that GE have variable individual properties and should not be considered as a single, homogenous class of compounds.
- Boogaard,De Kloe,Bierau,Kuiken,Borkulo,VanSittert
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p. 485 - 502
(2007/10/03)
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- Synthesis of [14C]-Labelled glycidyl and glycerol ethers of aliphatic and aromatic alcohols.
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The synthesis of [14C]-labelled glycidyl ethers and the corresponding glycerol ethers is described for the monofunctional compounds 1-dodecanol and ortho-cresol and the bifunctional compounds 4,4'-dihydroxy-3,3',5,5'-tetramethyl biphenyl and 1,6-hexanediol. The synthesis is based on reaction between the alcohol and [U-14C]-epichlorohydrin. The aromatic compounds have been converted to the corresponding glycidyl ethers by using sodium hydroxide and the aliphatic compounds by using tin(IV) chloride as a catalyst. Thus radio-labelled glycidyl ethers were obtained in yields between 50-80, with a chemical purity of > 92 and a radiochemical purity of > 95 by HPLC. The specific activities of the glycidyl ethers were approximately 0.2 mCi/mmol for the monofunctional compounds and approximately 0.4 mCi/mmol for the bifunctional compounds.
- Van Elburg,Ormskerk,De Kloe,Boogaard
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p. 147 - 167
(2007/10/03)
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