Process for preparing 3,3',4,4'-tetracarboxydiphthalic ether dianhydride

A technology of tetracarboxylic dianhydride and diphenyl ether, applied in 3 fields, can solve the problems of poor process stability, long process, difficulty in adding potassium carbonate and the like

Inactive Publication Date: 2006-09-06
HEILONGJIANG INST OF PETROCHEM
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

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Problems solved by technology

The disadvantages of this method are: the process is long, the operation is complicated, the total yield is low, the amount of three wastes is large, the cost is high, and it is difficult to be popularized and applied.
The operating conditions of this method are not easy to control, the process stability is not good, and it is difficult to add potassium carbonate at the same time, especially the water content is very harsh, below 10ppm, which is difficult to achieve in industrial production.

Method used

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Effect test

specific Embodiment approach 1

[0010] Specific embodiment one: this embodiment prepares 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride according to the following method: A, salt-forming reaction: add potassium hydroxide or sodium hydroxide in the reaction kettle, Make an aqueous solution with a mass concentration greater than 40%, control the reaction temperature of the solution at 60-120°C under stirring, add 4-halogenated phthalic anhydride to generate the corresponding potassium or sodium salt of 4-halogenated phthalate, and control the 4- The amount of halogenated phthalic anhydride and potassium hydroxide or sodium hydroxide is 2:1, and the pH value is about 7-10; after the reaction is completed, dehydrate under reduced pressure, and then vacuum-dry to make the water content lower than 1.0 % or less, the potassium salt or sodium salt of 4-halogenated phthalate is obtained, and the yield reaches more than 95%;

[0011] B. Condensation reaction: Add the above-mentioned obtained product 4-halogenate...

specific Embodiment approach 2

[0024] Specific embodiment two: This embodiment prepares 4-chlorophthalic acid potassium salt according to the following method: add 50wt.% KOH aqueous solution 100g in a 250ml three-necked bottle, add 4-chlorophthalic anhydride under heating and stirring, and control The reaction temperature is 60-100°C, and the pH value is adjusted at 7-10. After the reaction, dehydrate under reduced pressure, and then vacuum-dry to keep the water content below 1.0%, that is, 4-chlorophthalic acid Potassium salt, its yield reaches 98%.

specific Embodiment approach 3

[0025] Embodiment 3: This embodiment is different from Embodiment 2 in that KOH is replaced by NaOH, and the yield of the obtained 4-chlorophthalic acid sodium salt is 86.5%.

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Abstract

The method for preparation of 3, 3' ,4, 4'-diphenyloxide tetracarboxylic dianhydride belongs to the organic synthetic field. The purpose of this invention is to provide a method for preparation of 3, 3' ,4, 4'-diphenyloxide tetracarboxylic dianhydride, in which its preparation technology is simlple, process flow is short, cost is low, three wastesquantity is few, and its solvents can be retrieved and reused and its products can be easily purified. It includes the following steps: produing the corresponding 4-halogenated potassium phthalate or natrium phthalate by the reaction between 4-halogenated benzoic anhydride and caustic potash or caustic soda; condensing the product of the former step and 4-halogenated benzoic anhydride in the non-polar solvent of dichlorobenzene or trichlorobenzene with organophosphorus compound and/or copper compound as its phase transfer catalyst to obtain monoether anhydride; hydrolyzing the obtained monoether anhydride in the organic acid to prepare monoether acid, afterwards, and closing loop and dehydrating them in the miscible liquids of ethyl acetate and acetic anhydride to prepare purified monoether anhydride. The method for preparation of monoether anhydride can easily control reaction conditions, and is of good stability, especially, is of no strict demand for water.

Description

technical field [0001] The invention belongs to the field of organic synthesis and relates to a preparation method of 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride. Background technique [0002] 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride (referred to as monoether anhydride ODPA) is an important monomer for the synthesis of polyimides. Since monoether anhydride contains ether-based flexible groups, Polyimide (PEI) synthesized with monoether anhydride as a monomer can increase the flexibility of the entire molecular chain, and is also conducive to improving the solubility and extensibility of the polymer, thereby reducing the intermolecular force and reducing vitrification. temperature, its processing performance has been significantly improved, and it has more excellent performance. Monoether anhydride is a very useful chemical intermediate, which can further prepare the corresponding tetraacids and their derivatives such as esters, acid halide compounds, am...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07D307/89
Inventor 张春荣胡永玲张惠韩大维于明惠
Owner HEILONGJIANG INST OF PETROCHEM
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