38103-06-9Relevant articles and documents
Preparation method of aromatic diether dianhydride
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Paragraph 0025; 0029; 0034-0035; 0040, (2021/02/06)
The invention discloses a preparation method of aromatic diether dianhydride, which comprises the following steps of: by using isobutene or tert-butyl alcohol as a protecting group of carboxyl of chlorinated or nitrophthalic acid, carrying out etherification reaction with disodium bisphenol salt to obtain an intermediate, removing the tert-butyl ester protecting group in the intermediate by usinga small amount of acid without strong alkali treatment to obtain diether tetracarboxylic acid, and finally, enabling the solid tetracarboxylic acid to directly form anhydride at a proper temperature,wherein acetic anhydride dehydration is not needed, and the reaction time of the whole process is only about 21 hours. The preparation method of the aromatic diether dianhydride is short in reaction period, simple and safe in process, high in production efficiency and low in production cost.
Preparation method of aromatic diether dianhydride
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, (2019/12/02)
The invention relates to a preparation method of aromatic diether dianhydride, which comprises the following steps: (1) pouring a bisphenol compound, N-substituted phthalimide and a catalyst into a mixed solvent, carrying out heating reflux to remove water and carrying out substitution reaction to obtain N-substituted diether imide; (2) adding alkali metal hydroxide and water into the N-substituted diether imide obtained in the step (1), heating the mixture, carrying out hydrolysis reaction, cooling, adding protonic acid, separating out solid, collecting the solid, and drying the solid; and (3) dissolving the dried solid in a mixed solution of acetic acid and acetic anhydride, carrying out heating reflux, cooling, filtration and solid collection in sequence, recrystallizing the collected solid with a mixed solution of acetonitrile and toluene, performing filtration, collecting the solid, and drying the solid to obtain the product. The preparation method of the aromatic diether dianhydride has the advantages that the steps are simplified, the consumed time is short, the used solvent is easy to recycle and can be repeatedly used, and the prepared product aromatic diether dianhydrideis high in purity and yield.
Method for preparing bisphenol A diether dianhydride
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Paragraph 0011; 0012; 0014, (2018/07/15)
The invention relates to a method for preparing bisphenol A diether dianhydride. The method comprises the following steps that: the molar ratio of sodium hydroxide to bisphenol A is (2.1-2.3) to 1, the molar ratio of 4-chlorophthalic anhydride to phenol A is (2-2.1) to 1, the weight of a catalyst benzyl triethyl ammonium chloride is 15% by weight of the weight of bisphenol A, and the amount of a solvent trimethylbenzene is 8 times larger than the weight of bisphenol A; the preparation process is as follows: adding an aqueous solution of sodium hydroxide and bisphenol A to areactor, heating, stirring and dissolving at a temperature, heating to 85 DEG C to 90 DEG C, adding the trimethylbenzene and benzyl triethyl ammonium chloride which accounts 46% by weight of the total weight, heating toreflux, dewatering, stirring at a temperature of 172 DEG C and reacting for 15 to 18 hours, cooling to 130 DEG C, adding 4-chlorophthalic anhydride and benzyl triethyl ammonium chloride which accounts54% by weight of the total weight, heating 140 DEG C to 145 DEG C, performing a reflux reaction for 5 to 6 hours, filtering while hot, cooling a filtrate to room temperature, filtering, washing a precipitate with deionized water and ethanol respectively, filtering to obtain a wet material, and drying to obtain a bisphenol A diether dianhydride product with a yield of 80 to 85%. .