85954-11-6Relevant articles and documents
Cross-linked polybenzimidazole with enhanced stability for high temperature proton exchange membrane fuel cells
Han, Miaomiao,Zhang, Gang,Liu, Zhongguo,Wang, Shuang,Li, Mingyu,Zhu, Jing,Li, Hongtao,Zhang, Yang,Lew, Christopher M.,Na, Hui
, p. 2187 - 2193 (2011)
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.
Liquid crystal epoxy photosensitive resin and preparation method thereof
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, (2021/12/07)
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.
The method for producing the epoxy compound
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Paragraph 0085-0086, (2018/07/03)
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