CN111349065B - Preparation method of 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride - Google Patents
Preparation method of 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride Download PDFInfo
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Abstract
The invention discloses a preparation method of 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride, which comprises the steps of carrying out self-condensation reaction on halogenated phthalic anhydride in an organic solvent in the presence of an alkaline catalyst and a phase transfer catalyst to obtain 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride; the alkaline catalyst is an alkaline catalyst solution obtained by adding anhydrous potassium carbonate powder and anhydrous cesium carbonate powder into an organic solvent and mashing the mixture. The invention firstly crushes the powdery solid catalyst in the organic solvent at high speed to obtain the liquid catalyst, and then the liquid catalyst is dripped into the reaction system containing the halogenated phthalic anhydride and the phase transfer catalyst, thus greatly improving the mixing degree of reaction materials, greatly accelerating the reaction speed and shortening the reaction time. According to the invention, a small amount of cesium carbonate and potassium carbonate are added to form the mixed catalyst, so that the catalytic effect can be greatly improved, the reaction speed is further increased, and the reaction time is shortened.
Description
Technical Field
The invention belongs to the technical field of polyimide dianhydride monomer preparation, and particularly relates to a preparation method of 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride.
Background
Polyimide (polyimide) is a high-performance organic material, generally prepared by condensation polymerization of dibasic anhydride and diamine, has excellent heat resistance, oxidation resistance, radiation resistance and comprehensive physical properties, and is widely applied to the aspects of military industry, aerospace, high-end electronic materials and the like.
3,3',4,4' -diphenyl ether tetracarboxylic dianhydride (ODPA for short) is a polyimide monomer with excellent performance, and due to the fact that the polyimide monomer contains ether bonds, the flexibility of the whole molecular chain is increased, the solubility and the extensibility of a polymer are improved, intermolecular acting force is reduced, the processing performance of the material is improved, and the application range of related materials is greatly expanded.
At present, the following methods are mainly used for synthesizing 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride:
(1) phthalic anhydride method: 4-nitro-N-methyl phthalimide is prepared from phthalic anhydride, 3',4,4' -diphenyl ether tetracarboxylic acid is prepared by self-condensation, and 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride is obtained by dehydration.
The method has the following defects: the synthesis route is long, the total yield is low, a large amount of acidic waste water is generated, and the method is not environment-friendly.
(2) Oxidation of tetramethyldiphenyl ether: firstly, condensing 3, 4-dimethylphenol and 4-bromo-o-xylene to obtain tetramethyl diphenyl ether, oxidizing to obtain 3,3',4,4' -diphenyl ether tetracarboxylic acid, and finally dehydrating to obtain 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride.
The method has the following defects: the raw materials are not easy to obtain, the oxidation reaction difficulty is high, the risk is high, and the yield is low.
(3) Condensing halogenated phthalic anhydride and hydroxyl phthalic anhydride.
The method has the following disadvantages: the operation is more complicated, the byproducts are more, the purification difficulty is high, and the yield is lower.
(4) The halogenated phthalic anhydride is firstly reacted with sodium hydroxide/potassium hydroxide to obtain sodium salt/potassium salt, and then condensed with the halogenated phthalic anhydride.
The method has the following disadvantages: the purification operation is complicated and the requirement is strict.
(5) Halogenated phthalic anhydride self-condensation method.
The method has the advantages that: the purification operation is simple, the product purity is high, and particularly, the yield is obviously superior to that of the method.
The method has the following defects: the reaction is heterogeneous, so the reaction speed is slow and the reaction time is long.
Non-patent document 1: sudonimei et al, "research on synthesis and purification of 3,3',4,4' -diphenylether tetracarboxylic dianhydride", No. 6 in 2004, pages 362-364.
Non-patent document 2: wangzhenping et al, "Synthesis of Diphenyl ether tetracarboxylic dianhydride", 5 th stage of 2004, fine chemical raw materials and intermediates, pages 26-27 and 32.
Non-patent document 3: wangzhenping et al, "study on synthetic method of Diphenyl ether tetracarboxylic dianhydride", fine chemical raw materials and intermediates, No. 2 in 2005, pages 24-25.
Non-patent document 4: zhang Chunrong et al, "3, 3',4,4' -Diphenyl ether tetracarboxylic dianhydride Synthesis progress", Heilongjiang science, 2010, Vol.1, No. 5, p.27-30.
Patent document 1: CN1324794A, published 2001, 12 and 5.
Patent document 2: CN1706846A, published 12/14/2005.
Patent document 3: CN108250168A, published 2018, 7 and 6.
Disclosure of Invention
The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for preparing 3,3',4,4' -diphenylether tetracarboxylic dianhydride which can greatly shorten the reaction time while ensuring high yield and purity.
The technical scheme for realizing the purpose of the invention is as follows: a preparation method of 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride, which is to carry out self-condensation reaction on halogenated phthalic anhydride in an organic solvent in the presence of an alkaline catalyst and a phase transfer catalyst to obtain 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride; the alkaline catalyst is an alkaline catalyst solution; the alkaline catalyst solution is obtained by adding anhydrous potassium carbonate powder and anhydrous cesium carbonate powder into an organic solvent and mashing.
The molar ratio of the anhydrous potassium carbonate powder to the halogenated phthalic anhydride is 0.2: 1-0.5: 1.
The molar ratio of the anhydrous cesium carbonate powder to the halogenated phthalic anhydride is 0.01: 1-0.05: 1.
The temperature of the mashing is 50-95 ℃, and preferably 65-75 ℃.
The mashing speed is 10000-15000 rpm.
The halogenated phthalic anhydride is one of 4-fluorobenzoic anhydride, 4-chlorophthalic anhydride, 4-bromobenzoic anhydride and 4-iodophthalic anhydride, and is preferably 4-chlorophthalic anhydride.
The organic solvent is one or more than two (including two) of 1,2, 4-trichlorobenzene, sulfolane, o-dichlorobenzene, DMAc and trimethylbenzene; preferably 1,2, 4-trichlorobenzene and/or sulfolane; more preferably a mixed solvent consisting of 1,2, 4-trichlorobenzene and sulfolane according to the volume ratio of 1: 2-2: 1.
The dosage of the phase transfer catalyst is 0.5 to 5 percent of the weight of the halogenated phthalic anhydride, and preferably 1 to 3 percent.
The phase transfer catalyst is one or more than two (including two) of tetraphenyl phosphonium bromide, tetraphenyl phosphonium chloride, triphenylphosphine, tetrabutylphosphonium bromide and tetrabutylphosphonium chloride; preferably tetraphenylphosphonium bromide and/or triphenylphosphine; more preferably a mixed phase transfer catalyst consisting of tetraphenylphosphonium bromide and triphenylphosphine in a weight ratio of 1: 2-2: 1.
The dropping temperature of the alkaline catalyst solution is 160-210 ℃, and preferably 190-210 ℃.
The self-condensation reaction temperature is 170-220 ℃, and preferably 200-220 ℃.
The invention has the following positive effects:
(1) the invention firstly crushes the powdery solid catalyst in the organic solvent at high speed to obtain the liquid catalyst, and then drops the liquid catalyst into the reaction system containing the halogenated phthalic anhydride and the phase transfer catalyst, thereby greatly improving the mixing degree of reaction materials, greatly accelerating the reaction speed and shortening the reaction time.
(2) According to the invention, a small amount of cesium carbonate and potassium carbonate are added to form the mixed catalyst, so that the catalytic effect can be greatly improved, the reaction speed is further increased, and the reaction time is shortened.
(3) The catalyst addition mode of the invention can also effectively avoid bringing water into the reaction system, and the acceleration of the reaction speed can also effectively reduce the external interference on the reaction system, thereby greatly improving the stability of the production process and the product quality.
Detailed Description
(example 1)
The preparation method of 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride of this example is as follows:
adding 100mL of 1,2, 4-trichlorobenzene into a triturating kettle under the protection of nitrogen, then adding 27.6g of anhydrous potassium carbonate powder (0.2 mol) and 3.26g of anhydrous cesium carbonate powder (0.01 mol), sealing the triturating kettle, and triturating at the temperature of 70 +/-2 ℃ and the rotating speed of 12000rpm for 10min to obtain an alkaline catalyst solution.
② adding 100mL of 1,2, 4-trichlorobenzene, 91.3g of 4-chlorophthalic anhydride (0.5 mol) and 2.0g of tetraphenylphosphonium bromide (TPPB) into a reaction device, heating to 195 +/-2 ℃ under the protection of nitrogen, dripping the alkaline catalyst solution obtained in the step I, finishing dripping for about 3.5 hours, heating to 205 +/-2 ℃ after finishing dripping, and keeping the temperature for reaction to be complete (about 5 hours).
③ cooling the reaction system obtained in the step II to 90 +/-2 ℃, filtering while the reaction system is hot, cooling and crystallizing the filtrate, and filtering to obtain 62.0g of crude 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride.
Fourthly, the crude product obtained in the third step is added into a mixed solvent (80 mL of acetic acid and 80mL of acetic anhydride), heated and refluxed for 3 hours, cooled and filtered to obtain 55.8g of white crystalline powder of 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride refined product, the HPLC purity is 99.86%, and the yield is 72.0%.
(examples 2 to 5)
The preparation method of each example is basically the same as that of example 1 except for the differences shown in table 1.
TABLE 1
| Example 1 | Comparative example 1 | Example 2 | Example 3 | Example 4 | Examples5 | |
| Anhydrous potassium carbonate powder | 0.2mol | 0.2mol | 0.2mol | 0.2mol | 0.2mol | 0.1mol |
| Anhydrous cesium carbonate powder | 0.01mol | / | 0.01mol | 0.01mol | 0.01mol | 0.01mol |
| Step (i) organic solvent | Trichlorobenzene 100mL | Trichlorobenzene 100mL | O-dichlorobenzene 100mL | Trichlorobenzene 100mL | Sulfolane 80mL | Trichlorobenzene 100mL |
| Step (II) organic solvent | Trichlorobenzene 100mL | Trichlorobenzene 100mL | O-dichlorobenzene 100mL | Trichlorobenzene 100mL | 120mL of trichlorobenzene | Trichlorobenzene 100mL |
| Tetraphenylphosphonium bromide | 2.0g | 2.0g | 2.0g | 1.0g | 1.0g | 1.0g |
| Triphenylphosphine | / | / | / | 1.0g | 1.0g | 1.0g |
| Dropping temperature of alkaline catalyst solution | 195±2℃ | 195±2℃ | 172±2℃ | 195±2℃ | 195±2℃ | 195±2℃ |
| Temperature of self-condensation reaction | 205±2℃ | 205±2℃ | 178±2℃ | 205±2℃ | 205±2℃ | 205±2℃ |
| Step II reaction time | About 4.5h | About 10h | About 6h | About 4.5h | About 4h | About 6h |
| Crude weight | 62.0g | 58.0g | 58.2g | 63.6g | 65.0g | 60.0g |
| Weight of boutique | 55.8g | 52.2g | 53.2g | 57.6g | 58.2g | 54.3g |
| HPLC purity | 99.86% | 99.79% | 99.73% | 99.86% | 99.84% | 99.80% |
| Yield of | 72.0% | 67.4% | 68.6% | 74.3% | 75.1% | 70.0% |
Comparative example 1
Comparative example 1 was prepared substantially the same as example 1 except as shown in table 1.
Comparative example 2
The preparation method of 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride of the present comparative example is as follows:
200mL of 1,2, 4-trichlorobenzene, 91.3g of 4-chlorophthalic anhydride (0.5 mol) and 2.0g of tetraphenylphosphonium bromide (TPPB) are added into a reaction device under the protection of nitrogen, the temperature is raised to 195 +/-2 ℃, a powder catalyst obtained by mixing 27.6g of anhydrous potassium carbonate powder (0.2 mol) and 3.3g of anhydrous cesium carbonate powder (0.01 mol) is slowly added, the addition is finished for about 2 hours, the temperature is raised to 205 +/-2 ℃ after the addition is finished, and the temperature is kept for reaction until the reaction is finished (about 18 hours).
② cooling the reaction system of the first step to 90 +/-2 ℃, filtering while hot, cooling the filtrate for crystallization, and filtering to obtain 57.0g of crude 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride.
③ adding the crude product obtained in the step II into a mixed solvent (80 mL of acetic acid and 80mL of acetic anhydride), heating and refluxing for 3h, cooling, filtering to obtain white crystalline powder of 50.6g of refined 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride, the HPLC purity is 99.28 percent, and the yield is 65.3 percent.
Comparative example 3
The preparation method of 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride of the present comparative example is as follows:
200mL of 1,2, 4-trichlorobenzene, 91.3g of 4-chlorophthalic anhydride (0.5 mol) and 2.0g of tetraphenylphosphonium bromide (TPPB) are added into a reaction device under the protection of nitrogen, the temperature is raised to 195 +/-2 ℃, 27.6g of anhydrous potassium carbonate powder (0.2 mol) is slowly added, the addition is completed within 2 hours, the temperature is raised to 205 +/-2 ℃ after the addition is completed, and the reaction is kept at the temperature until the reaction is completed (about 21 hours).
② cooling the reaction system of the step I to 90 +/-2 ℃, filtering while hot, cooling the filtrate for crystallization, and filtering to obtain 53.7g of crude 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride.
③ adding the crude product obtained in the step II into a mixed solvent (80 mL of acetic acid and 80mL of acetic anhydride), heating and refluxing for 3h, cooling, filtering to obtain white crystalline powder of 48.6g of refined 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride, the HPLC purity is 99.05 percent, and the yield is 62.7 percent.
Claims (3)
1. A3, 3',4,4' -diphenyl ether tetracarboxylic dianhydride preparation method, it is in presence of basic catalyst and phase transfer catalyst by halogenated phthalic anhydride, in organic solvent, get 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride through the self-condensation reaction; the method is characterized in that: the alkaline catalyst is an alkaline catalyst solution; the alkaline catalyst solution is obtained by adding anhydrous potassium carbonate powder and anhydrous cesium carbonate powder into an organic solvent and mashing; the molar ratio of the anhydrous cesium carbonate powder to the halogenated phthalic anhydride is 0.01: 1-0.05: 1; the molar ratio of the anhydrous potassium carbonate powder to the halogenated phthalic anhydride is 0.2: 1-0.5: 1; the halogenated phthalic anhydride is 4-fluorobenzoic anhydride;
the organic solvent is one or more than two of 1,2, 4-trichlorobenzene, sulfolane, o-dichlorobenzene, DMAc and trimethylbenzene;
the phase transfer catalyst is one or more than two of tetraphenyl phosphonium bromide, tetraphenyl phosphonium chloride, triphenylphosphine, tetrabutylphosphonium bromide and tetrabutylphosphonium chloride; the dosage of the phase transfer catalyst is 0.5 to 5 percent of the weight of the halogenated phthalic anhydride;
the dropping temperature of the alkaline catalyst solution is 160-210 ℃, and the self-condensation reaction temperature is 170-220 ℃.
2. The method of preparing 3,3',4,4' -diphenylether tetracarboxylic dianhydride according to claim 1, wherein: the organic solvent is a mixed solvent composed of 1,2, 4-trichlorobenzene and sulfolane according to the volume ratio of 1: 2-2: 1.
3. The method of producing 3,3',4,4' -diphenylether tetracarboxylic dianhydride according to claim 1, wherein: the phase transfer catalyst is a mixed phase transfer catalyst composed of tetraphenyl phosphonium bromide and triphenylphosphine according to the weight ratio of 1: 2-2: 1.
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| CN1246107A (en) * | 1997-12-02 | 2000-03-01 | 玛奈克股有限公司 | Method for preparing oxy-diphthalic anhydrides |
| CN1321794A (en) * | 2001-02-28 | 2001-11-14 | 江苏石油化工学院 | Method for treating waste liquor from acid pickling steel plate with hydrochloric acid |
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|---|---|---|---|---|
| CN1246107A (en) * | 1997-12-02 | 2000-03-01 | 玛奈克股有限公司 | Method for preparing oxy-diphthalic anhydrides |
| CN1321794A (en) * | 2001-02-28 | 2001-11-14 | 江苏石油化工学院 | Method for treating waste liquor from acid pickling steel plate with hydrochloric acid |
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