CN117466754B - Indane structural compound crystallization method for epoxy resin curing agent - Google Patents
Indane structural compound crystallization method for epoxy resin curing agent Download PDFInfo
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- CN117466754B CN117466754B CN202311818829.8A CN202311818829A CN117466754B CN 117466754 B CN117466754 B CN 117466754B CN 202311818829 A CN202311818829 A CN 202311818829A CN 117466754 B CN117466754 B CN 117466754B
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- pida
- epoxy resin
- curing agent
- resin curing
- aminophenyl
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- 238000002425 crystallisation Methods 0.000 title claims abstract description 33
- PQNFLJBBNBOBRQ-UHFFFAOYSA-N indane Chemical compound C1=CC=C2CCCC2=C1 PQNFLJBBNBOBRQ-UHFFFAOYSA-N 0.000 title claims abstract description 18
- 239000003795 chemical substances by application Substances 0.000 title claims abstract description 13
- 239000003822 epoxy resin Substances 0.000 title claims abstract description 13
- 229920000647 polyepoxide Polymers 0.000 title claims abstract description 13
- 150000001875 compounds Chemical class 0.000 title claims abstract description 10
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims abstract description 40
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims abstract description 30
- 238000001816 cooling Methods 0.000 claims abstract description 22
- 230000008025 crystallization Effects 0.000 claims abstract description 22
- 239000003208 petroleum Substances 0.000 claims abstract description 20
- 238000001035 drying Methods 0.000 claims abstract description 18
- 239000013078 crystal Substances 0.000 claims abstract description 15
- UKJLNMAFNRKWGR-UHFFFAOYSA-N cyclohexatrienamine Chemical group NC1=CC=C=C[CH]1 UKJLNMAFNRKWGR-UHFFFAOYSA-N 0.000 claims abstract description 14
- 238000001914 filtration Methods 0.000 claims abstract description 11
- 238000000034 method Methods 0.000 claims abstract description 9
- 239000002244 precipitate Substances 0.000 claims abstract description 4
- 239000007787 solid Substances 0.000 claims abstract description 4
- 238000010438 heat treatment Methods 0.000 claims description 20
- 238000002156 mixing Methods 0.000 claims description 3
- 238000010583 slow cooling Methods 0.000 claims description 2
- 238000003756 stirring Methods 0.000 claims description 2
- 241000801593 Pida Species 0.000 abstract description 41
- ZBIKORITPGTTGI-UHFFFAOYSA-N [acetyloxy(phenyl)-$l^{3}-iodanyl] acetate Chemical compound CC(=O)OI(OC(C)=O)C1=CC=CC=C1 ZBIKORITPGTTGI-UHFFFAOYSA-N 0.000 abstract description 41
- 239000000047 product Substances 0.000 abstract description 21
- 238000009776 industrial production Methods 0.000 abstract description 3
- 239000002904 solvent Substances 0.000 abstract description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 12
- 230000000052 comparative effect Effects 0.000 description 8
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 6
- 238000005303 weighing Methods 0.000 description 6
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 4
- 230000001376 precipitating effect Effects 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- IMNFDUFMRHMDMM-UHFFFAOYSA-N N-Heptane Chemical compound CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 description 3
- -1 indane structure compound Chemical class 0.000 description 3
- 239000000178 monomer Substances 0.000 description 3
- 239000004642 Polyimide Substances 0.000 description 2
- 150000004985 diamines Chemical class 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229920001721 polyimide Polymers 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 230000000630 rising effect Effects 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000383 hazardous chemical Substances 0.000 description 1
- 231100000206 health hazard Toxicity 0.000 description 1
- 238000004128 high performance liquid chromatography Methods 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- SYSQUGFVNFXIIT-UHFFFAOYSA-N n-[4-(1,3-benzoxazol-2-yl)phenyl]-4-nitrobenzenesulfonamide Chemical class C1=CC([N+](=O)[O-])=CC=C1S(=O)(=O)NC1=CC=C(C=2OC3=CC=CC=C3N=2)C=C1 SYSQUGFVNFXIIT-UHFFFAOYSA-N 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/82—Purification; Separation; Stabilisation; Use of additives
- C07C209/84—Purification
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2602/00—Systems containing two condensed rings
- C07C2602/02—Systems containing two condensed rings the rings having only two atoms in common
- C07C2602/04—One of the condensed rings being a six-membered aromatic ring
- C07C2602/08—One of the condensed rings being a six-membered aromatic ring the other ring being five-membered, e.g. indane
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a crystallization method of an indane structural compound for an epoxy resin curing agent, which comprises the following steps: s1, 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan, isopropanol and petroleum ether are mixed and heated to 60-70 ℃ to be completely dissolved; s2, slowly cooling to 40-45 ℃ to start turbidity and precipitate solids, preserving heat for 0.5-2 h, quickly cooling to-5-0 ℃ and preserving heat for 1-6 h; s3, filtering and drying to obtain PIDA crystals; the method solves the problem of difficult crystallization of PIDA, the purity of the product is over 99.8 percent, the yield is over 90 percent, the isomer ratio is close to 1:1, the solvent is easy to obtain, the operation is simple, and the method is convenient for industrial production.
Description
Technical Field
The invention relates to the technical field of organic synthesis crystallization, in particular to a crystallization method of an indane structure compound for an epoxy resin curing agent.
Background
5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan, abbreviated as: PIDA, a mixture of a pair of isomers, CAS number: 104983-63-3, isomer ratio: 45/55+ -5, structural formula:
;
the molecule contains a cyclic indane structure, has good thermal stability and oxidation resistance, and the methyl in the molecule leads benzene rings to generate induced dipoles, so that the molecule has good compatibility with a plurality of high polymer materials, and is often used as a curing agent of epoxy resin. The PIDA melting point is lower, the curing temperature of a curing system is reduced, but the cured product still has better heat resistance. In addition, PIDA has higher solubility in common organic solvents, is also an excellent diamine monomer for preparing soluble polyimide, and the purity of PIDA is a key factor for preparing soluble polyimide.
PIDA has a low melting point, is a mixture of diamine monomers, and has the problems of difficult crystallization, easy precipitation of oily matters, low product yield, large deviation of isomer ratio and the like in the purification process. U.S. Pat. nos. 3856752 and 3983092 use PIDA monomers to make XU218 without purification of the PIDA, and use of toluene-containing melts has potential health hazards and quality disadvantages. The patent US4454347 uses acetic acid for washing and acid clay treatment to eliminate polyamino compounds, then uses toluene and n-heptane for crystallization, and has the advantages of longer crystallization time, complex operation process and lower production efficiency.
Disclosure of Invention
The invention provides a crystallization method of an indane structure compound for an epoxy resin curing agent.
The scheme of the invention is as follows:
a crystallization method of an indane structural compound for an epoxy resin curing agent, comprising the steps of:
s1, mixing 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan, isopropanol and petroleum ether, heating and completely dissolving;
s2, slowly cooling to 40-45 ℃ to start turbidity and precipitate solids, preserving heat for 0.5-2 h, quickly cooling to-5-0 ℃ and preserving heat for 1-6 h;
s3, filtering and drying to obtain the 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan crystal.
As a preferable technical scheme, the mass ratio of the 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindane to the isopropanol in the S1 is 1:1-3; the mass ratio of the 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan to the petroleum ether is 1:2-10.
As a preferable technical scheme, 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan, isopropanol and petroleum ether in the S1 are added into a crystallization kettle, the crystallization kettle is provided with a stirring device and a heating jacket, and the temperature is raised to 60-70 ℃.
As an optimal technical scheme, the slow cooling speed in the S2 is 2-10 ℃/h, and the fast cooling speed is 20-30 ℃/h.
As a preferable technical scheme, the filtering in the S3 is carried out in an environment with the temperature of-5 to 0 ℃.
As a preferable technical scheme, the drying process in the step S3 is that the drying is carried out for 1-3 hours at 20-30 ℃ under vacuum condition, and then the temperature is raised to 50-60 ℃ for 3-6 hours.
Because the technical scheme is adopted, the crystallization method of the indane structural compound for the epoxy resin curing agent comprises the steps of S1, mixing the 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindane, isopropanol and petroleum ether, heating and completely dissolving; s2, slowly cooling to 40-45 ℃ to start turbidity and precipitate solids, preserving heat for 0.5-2 h, quickly cooling to-5-0 ℃ and preserving heat for 1-6 h; s3, filtering and drying to obtain the 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan crystal.
The invention has the advantages that:
the method solves the problem of difficult crystallization of PIDA, the purity of the product is over 99.8 percent, the yield is over 90 percent, the isomer ratio is close to 1:1, the solvent is easy to obtain, the operation is simple, and the method is convenient for industrial production.
Detailed Description
The invention provides a crystallization method of an indane structure compound for an epoxy resin curing agent.
In order to make the technical means, the creation characteristics, the achievement of the purpose and the effect of the present invention easy to understand, the present invention is further described below with reference to the specific embodiments.
Example 1:
(1) Weighing a certain amount of PIDA (purity is 98.5%, proportion is 48:52), isopropanol and petroleum ether, adding into a crystallization kettle, setting a stirrer and a heating jacket in the crystallization kettle, wherein the mass ratio of the PIDA to the isopropanol is 1:2, the mass ratio of the PIDA to the petroleum ether is 1:6, and completely dissolving the PIDA and the petroleum ether at the internal temperature of 65 ℃;
(2) Slowly cooling to 40 ℃ at 5 ℃ per hour to start clouding and precipitating crystals, preserving heat for 1 hour, rapidly cooling to-2 ℃ at 20 ℃ per hour, and preserving heat for 2 hours; the heating medium in the heating jacket is changed into a refrigerating medium, and rapid cooling is performed, for example, a low-carbon alcohol refrigerating medium;
(3) Filtering at-2 ℃, drying at 25 ℃ for 2 hours under vacuum, heating to 55 ℃ and drying for 5 hours to obtain PIDA crystals. The purity of the test product is 99.9%, the ratio is 49:51, and the yield is 94%.
Example 2:
(1) Weighing a certain amount of PIDA (purity is 98.5%, proportion is 48:52), isopropanol and petroleum ether, adding into a crystallization kettle, setting a stirrer and a heating jacket in the crystallization kettle, wherein the mass ratio of the PIDA to the isopropanol is 1:1, the mass ratio of the PIDA to the petroleum ether is 1:2, and completely dissolving the PIDA and the petroleum ether at the internal temperature of 60 ℃;
(2) Slowly cooling to 40 ℃ at 2 ℃/h to start clouding and precipitating crystals, preserving heat for 0.5h, rapidly cooling to-5 ℃ at 25 ℃/h, and preserving heat for 1h;
(3) Filtering at-5 ℃, drying at 20 ℃ for 1h under vacuum, heating to 50 ℃ and drying for 3h to obtain PIDA crystals. The purity of the test product is 99.9%, the ratio is 49:51, and the yield is 93%.
Example 3:
(1) Weighing a certain amount of PIDA (purity is 98.5%, proportion is 48:52), isopropanol and petroleum ether, adding into a crystallization kettle, setting a stirrer and a heating jacket in the crystallization kettle, wherein the mass ratio of the PIDA to the isopropanol is 1:3, the mass ratio of the PIDA to the petroleum ether is 1:10, and completely dissolving the PIDA and the petroleum ether at the internal temperature rising temperature of 70 ℃;
(2) Slowly cooling to 40 ℃ at 10 ℃/h to start clouding and precipitating crystals, preserving heat for 2h, rapidly cooling to 0 ℃ at 30 ℃/h, and preserving heat for 6h;
(3) Filtering at 0 ℃, drying at 30 ℃ for 3 hours under vacuum, heating to 60 ℃ and drying for 6 hours to obtain PIDA crystals. The purity of the test product is 99.9%, the ratio is 49:51, and the yield is 96%.
Comparative example 1:
(1) Weighing a certain amount of PIDA (purity is 98.5%, proportion is 48:52), toluene and petroleum ether, adding into a crystallization kettle, setting a stirrer and a heating jacket in the crystallization kettle, wherein the mass ratio of the PIDA to the toluene is 1:2, the mass ratio of the PIDA to the petroleum ether is 1:6, and completely dissolving the PIDA and the petroleum ether at the internal temperature of 65 ℃;
(2) Slowly cooling to 40 ℃ at 5 ℃ per hour to separate out oily matters, and PIDA crystals cannot be obtained.
Comparative example 2
(1) Weighing a certain amount of PIDA (purity is 98.5%, proportion is 48:52), methylene dichloride and normal hexane, adding the PIDA, methylene dichloride and normal hexane into a crystallization kettle, setting a stirrer and a heating jacket in the crystallization kettle, wherein the mass ratio of the PIDA to the methylene dichloride is 1:2, the mass ratio of the PIDA to the normal hexane is 1:6, and completely dissolving the PIDA and the normal hexane by internal temperature rising to 60 ℃;
(2) Slowly cooling to 42 ℃ at 5 ℃/h to start turbid crystal precipitation, preserving heat for 1h, rapidly cooling to 0 ℃ at 20 ℃/h, and preserving heat for 2h;
(3) Filtering at 0 ℃, drying at 25 ℃ for 2 hours under vacuum, heating to 55 ℃ and drying for 6 hours to obtain PIDA crystals. The purity of the test product is 99.5%, the ratio is 91:9, and the yield is 52%.
Comparative example 3
(1) Weighing a certain amount of PIDA (purity is 98.5%, proportion is 48:52) and isopropanol, adding into a crystallization kettle, setting a stirrer and a heating jacket in the crystallization kettle, and heating to 60 ℃ for complete dissolution at an internal temperature of 1:2;
(2) Slowly cooling to 43 ℃ at 5 ℃/h to start clouding and precipitating crystals, preserving heat for 1h, rapidly cooling to 0 ℃ at 20 ℃/h, and preserving heat for 2h;
(3) Filtering at 0 ℃, drying at 25 ℃ for 2 hours under vacuum, heating to 55 ℃ and drying for 6 hours to obtain PIDA crystals. The purity of the test product is 99.6%, the ratio is 5:95, and the yield is 57%.
Comparing the product obtained in example 1 with comparative example 1, comparative example 2 and comparative example 3, and detailing the following tables 1 and 2, wherein the yield of each example in table 1 is above 90%, and the isomer ratio is close to 1:1;
table 1: comparative results Table for PIDA products obtained by the respective methods
As shown in Table 1, the crystallization method solves the problem of difficult crystallization of PIDA, the purity of the product of the crystallization method is over 99.8 percent, the yield is over 90 percent, the isomer ratio is close to 1:1, the solvent is easy to obtain, the operation is simple, and the industrial production is convenient.
Table 2: HPLC test results table for PIDA products obtained in examples and comparative examples
Remarks: RT is retention time in the liquid chromatogram; AREA is the percentage of peak AREA in the liquid chromatogram.
Polyamino product 1:polyamino product 2: />,
Product 1:product 2: />,
Isomer 1:isomer 2: />,
The "purity" in the table is: total purity of product 1 and product 2; the "yield" in the table is: total yield of product 1 and product 2.
The foregoing has shown and described the basic principles, main features and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (4)
1. A crystallization method of an indane structural compound for an epoxy resin curing agent, comprising the steps of:
s1, mixing 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan, isopropanol and petroleum ether, heating and completely dissolving; the mass ratio of the 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan to the isopropanol is 1:1-3; the mass ratio of the 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan to the petroleum ether is 1:2-10; adding the 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan, isopropanol and petroleum ether into a crystallization kettle which is provided with a stirring device and a heating jacket, and heating to 60-70 ℃;
s2, slowly cooling to 40-45 ℃ to start turbidity and precipitate solids, preserving heat for 0.5-2 h, quickly cooling to-5-0 ℃ and preserving heat for 1-6 h;
s3, filtering and drying to obtain the 5 (6) -amino-1- (4-aminophenyl) -1, 3-trimethylindan crystal.
2. A method for crystallizing an indane structured compound for an epoxy resin curing agent as claimed in claim 1, wherein: the slow cooling speed in the step S2 is 2-10 ℃/h, and the fast cooling speed is 20-30 ℃/h.
3. A method for crystallizing an indane structured compound for an epoxy resin curing agent as claimed in claim 1, wherein: and the filtering in the step S3 is carried out in an environment with the temperature of-5 to 0 ℃.
4. A method for crystallizing an indane structured compound for an epoxy resin curing agent as claimed in claim 1, wherein: and the drying process in the step S3 is that the drying is carried out for 1-3 hours at 20-30 ℃ under the vacuum condition, and then the temperature is increased to 50-60 ℃ for 3-6 hours.
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Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4454347A (en) * | 1983-02-11 | 1984-06-12 | Ciba-Geigy Corporation | Process for purification and isolation of diaminophenylindane |
CN111484412A (en) * | 2020-05-26 | 2020-08-04 | 上海华谊树脂有限公司 | Method for synthesizing compound containing indan structure |
CN112409187A (en) * | 2020-11-30 | 2021-02-26 | 山东华夏神舟新材料有限公司 | Synthesis method of 6-amino-1- (4-aminophenyl) -1,3,3-trimethylindane |
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- 2023-12-27 CN CN202311818829.8A patent/CN117466754B/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4454347A (en) * | 1983-02-11 | 1984-06-12 | Ciba-Geigy Corporation | Process for purification and isolation of diaminophenylindane |
CN111484412A (en) * | 2020-05-26 | 2020-08-04 | 上海华谊树脂有限公司 | Method for synthesizing compound containing indan structure |
CN112409187A (en) * | 2020-11-30 | 2021-02-26 | 山东华夏神舟新材料有限公司 | Synthesis method of 6-amino-1- (4-aminophenyl) -1,3,3-trimethylindane |
Non-Patent Citations (2)
Title |
---|
Chinnaswamy Thangavel Vijayakumar et al.Synthesis and Polymerization of Bismaleimide Derived from 5(6)-amino-1(4′-aminophenyl)-1,3,3′-trimethyl indane.Polymer-Plastics Technology and Engineering.2009,第48卷第141-151页. * |
凌钦才 等.5(6)-氨基-1-(4-氨基苯基)-1,3,3-三甲基茚满合成及工艺优化.广州化学.2019,第44卷(第6期),第36-40页. * |
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