- Organized surface functional groups: Cooperative catalysis via thiol/sulfonic acid pairing
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The synthesis and characterization of heterogeneous catalysts containing surfaces functionalized with discrete pairs of sulfonic acid and thiol groups are reported. A catalyst having acid and thiol groups separated by three carbon atoms is ca. 3 times more active than a material containing randomly distributed acid and thiol groups in the condensation of acetone and phenol to bisphenol A and 14 times more active in the condensation of cyclohexanone and phenol to bisphenol Z. Increasing the acid/thiol distance in the paired materials decreases both the activity and selectivity. This work clearly reveals the importance of nanoscale organization of two disparate functional groups on the surface of heterogeneous catalysts.
- Margelefsky, Eric L.,Zeidan, Ryan K.,Dufaud, Veronique,Davis, Mark E.
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- HF-mediated equilibrium between fluorinated ketones and the corresponding α-fluoroalcohols
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We have successfully obtained the first unambiguous spectroscopic proof of the structure of heptafluoropropan-2-ol by 13C NMR, which has been assumed from early 70s but without unequivocal evidence. Equilibrating relationship between fluorinated ketones and the corresponding hydrates as well as α-fluoroalcohols in anhydrous HF was at least qualitatively supported by our ab initio computation, and moreover, anhydrous HF as a convenient solvent was found to offer an effective new route for production of 1,1,1,3,3,3-hexafluoropropan-2-ol in industrial scales.
- Hayasaka, Tatsuya,Katsuhara, Yutaka,Kume, Takashi,Yamazaki, Takashi
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- Synthetic method of hexafluorobisphenol A
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The invention provides a synthetic method of hexafluorobisphenol A. The synthetic method comprises the following steps: a) reacting hexachloroacetone with phenol in the presence of a Lewis acid catalyst to obtain hexachlorobisphenol A; and b) carrying out fluorination reaction on the hexachlorobisphenol A and hydrogen fluoride to obtain the hexafluorobisphenol A. According to the method, Lewis acid is used as a catalyst to change the electronic reaction characteristics of the phenol, so that the intermediate hexachlorobisphenol A is obtained from the para-position carbon atom of the phenol andthe carbonyl group of the hexachloroacetone by addition elimination reaction to obtain, but not from the oxygen atom of the phenol and the chlorine atom of the hexachloroacetone by nucleophilic substitution reaction, and the hexafluorobisphenol A is obtained by fluorinating the hexachlorobisphenol A. According to the method, the hexachloroacetone which is low in price, easy to obtain and low in toxicity replaces hexafluoroacetone and hexafluoropropylene oxide to serve as a raw material, the requirement for equipment is low, safe production is facilitated, the production cost is reduced, and anew thought is provided for the synthetic method of the hexafluorobisphenol A. The hexafluorobisphenol A prepared by the method has the advantages of higher yield and higher purity.
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Paragraph 0030; 0032; 0033; 0034; 0036; 0037; 0039
(2020/04/17)
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- A diaryl hexafluoropropane synthetic method of the compound
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The invention provides a method for synthesizing a diaryl hexafluoropropane compound, and is characterized in that the method comprises the steps: firstly mixing aromatic hydrocarbon with anhydrous hydrogen fluoride in a reactor, then adding a catalyst, next adding hexafluoropropylene oxide, and followed by stirring and heating; after the reaction is finished, removing hydrogen fluoride, refining the remaining product, and thus obtaining the diaryl hexafluoropropane compound product, wherein the catalyst is SbCl5, TiCl4 or a mixture thereof. The method allows isomerization of hexafluoropropylene oxide and condensation reaction of aromatic hydrocarbon to be achieved through combining into a process stage, reduces the synthetic process steps, reduces the production cost and by-product generation, and greatly improves the yield of the product.
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Paragraph 0013; 0019; 0027-0034
(2017/04/11)
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- Diaryl hexafluoroacetore the synthetic method of the compound of
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The invention provides of a synthesis method of a diaryl hexafluoropropane compound. The method is characterized by comprising the following steps: firstly mixing aromatic hydrocarbon and anhydrous hydrogen fluoride in a reactor, adding a catalyst, and then adding hexafluoropropylene oxide, stirring and heating; removing hydrogen fluoride after the reaction is finished, and refining the rest product to obtain a diaryl hexafluoropropane compound product, wherein the catalyst is one or more of halogenated antimony and halogenated titanium system catalyst. Through the adoption of the method disclosed by the invention, isomerization and condensation reaction with the aromatic hydrocarbon of hexafluoropropylene oxide are realized in a process stage, the process step of the synthesis is reduced, the production cost and the byproduct production are reduced, and the yield of the product is greatly improved.
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Paragraph 0039-0040
(2017/02/09)
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- 2, 2-bis (4-hydroxyphenyl) propane hexafluoroisopropylether manufacturing method (by machine translation)
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The invention provides a method for manufacturing bisphenol AF. The method is a manufacturing method using hexafluoroacetone, phenol and hydrogen fluoride, is suitable for a convenient refining method, meanwhile can improve the yield and can reduce the load to the environment. A method for manufacturing 2,2-di(4-hydroxyphenyl)hexafluoropropane is characterized in that: the hexafluoroacetone and the phenol are reacted in the presence of the hydrogen fluoride, wherein when the reaction begins, based on 1 mole of phenol, the hexafluoroacetone is 0.55 to 2 moles and the hydrogen fluoride is 8 to 200 moles.
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Paragraph 0021; 0042-0056
(2018/11/22)
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- Polymer electrolyte and process for producing the same
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A polymer electrolyte having, in a main chain, a structural unit represented by the following formula (1):-[Ar1-(SO2-N-(X+)-SO2-Ar2)m-SO2-N-(X+)-SO2-Ar1-O]- wherein Ar1 and Ar2 independently represent a divalent aromatic groups, m represents an integer of 0 to 3, and X+ represents an ion selected from hydrogen ion, an alkali metal ion and ammonium ion, which is excellent in proton conductivity, thermal resistance and strength. The polymer electrolyte is soluble in solvents and has excellent film forming property and recycling efficiency.
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- Method for preparing aromatic bischloroformate compositions
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Bischloroformate oligomer compositions are prepared by passing phosgene into a heterogeneous aqueous-organic mixture containing at least one dihydroxyaromatic compound, with simultaneous introduction of a base at a rate to maintain a specific pH range and to produce a specific volume ratio of aqueous to organic phase. By this method, it is possible to employ a minimum amount of phosgene. The reaction may be conducted batchwise or continuously. The bischloroformate composition may be employed for the preparation of cyclic polycarbonate oligomers or linear polycarbonate, and linear polycarbonate formation may be integrated with bischloroformate composition formation in a batch or continuous process.
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- Bischoloroformate preparation method with phosgene removal and monochloroformate conversion
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Aqueous bischloroformates are prepared by the reaction of a dihydroxyaromatic compound (e.g., bisphenol A) with phosgene in a substantially inert organic liquid (e.g., methylene chloride) and in the presence of an aqueous alkali metal or alkaline earth metal base, at a pH below about 8. After all solid dihydroxyaromatic compound has been consumed, the pH is raised to a higher value in the range of about 7-12, preferably 9-11, and maintained in said range until a major proportion of the unreacted phosgene has been hydrolyzed. At the same time, any monochloroformate in the product may be converted to bischloroformate.
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- Cyclic monocarbonate bishaloformates
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Cyclic monocarbonate bischloroformates are prepared by the reaction of a carbonyl halide such as phosgene with a bridged substituted resorcinol or hydroquinone such as bis(2,4-dihydroxy-3-methylphenyl)methane or bis(2,5-dihydroxy-3,4,6-trimethylphenyl)methane in the presence of aqueous alkali metal hydroxide. The cyclic monocarbonate bischloroformates may be used for the preparation of linear or cyclic polycarbonates containing cyclic carbonate structural units, which may in turn be converted to crosslinked polycarbonates.
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- Polyetherimide bisphenol compositions
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Polyetherimide bisphenols and bischloroformates are prepared by the reaction of dianhydrides or certain bisimides with aminophenols or mixtures thereof with diamines. They are useful as intermediates for the preparation of cyclic heterocarbonates, which may in turn be converted to linear copolycarbonates. The bisphenols can also be converted to salts which react with cyclic polycarbonate oligomers to form block copolyetherimidecarbonates.
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