CN114195697B - Dichloro diphthalimide intermediate and synthetic method and application thereof - Google Patents
Dichloro diphthalimide intermediate and synthetic method and application thereof Download PDFInfo
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- CN114195697B CN114195697B CN202111567674.6A CN202111567674A CN114195697B CN 114195697 B CN114195697 B CN 114195697B CN 202111567674 A CN202111567674 A CN 202111567674A CN 114195697 B CN114195697 B CN 114195697B
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- C07D209/00—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom
- C07D209/02—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom condensed with one carbocyclic ring
- C07D209/44—Iso-indoles; Hydrogenated iso-indoles
- C07D209/48—Iso-indoles; Hydrogenated iso-indoles with oxygen atoms in positions 1 and 3, e.g. phthalimide
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- C08G75/00—Macromolecular compounds obtained by reactions forming a linkage containing sulfur with or without nitrogen, oxygen, or carbon in the main chain of the macromolecule
- C08G75/02—Polythioethers
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- C08G75/0227—Polyarylenethioethers derived from monomers containing two or more aromatic rings
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- C08G75/00—Macromolecular compounds obtained by reactions forming a linkage containing sulfur with or without nitrogen, oxygen, or carbon in the main chain of the macromolecule
- C08G75/02—Polythioethers
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Abstract
The invention relates to a dichloro diphthalimide intermediate, a synthesis method and application thereof, wherein the chloro-phthalic anhydride and diamine compound react for 5-20 hours in a nitrogen atmosphere at 50-200 ℃ in the presence of a solvent, a catalyst and a dehydrating agent, after the reaction is finished, the temperature is reduced and the filtration is carried out, and the filter cake is recrystallized, washed by alcohol or water and then filtered to obtain the dichloro diphthalimide. The synthesis process of the dichloro diphthalimide intermediate provided by the invention is simple, the acid is used as a catalyst to reduce the activation energy required by the reaction, and the provided acid environment well inhibits the reaction of the intermediate product polycondensation to generate polyamide. The method also uses the anhydride of the corresponding catalyst as a dehydrating agent, and the corresponding acid is further generated after the dehydration, so that the content of the catalyst is increased.
Description
Technical Field
The invention relates to a dichloro diphthalimide intermediate, a synthesis method and application thereof, and belongs to the technical field of fine organic synthesis.
Background
The novel engineering plastics of polyimide and polyetherimide are one of the organic high polymer materials with the best comprehensive performance at present, and have dual temperature resistance performance of high temperature resistance and low temperature resistance, and the long-term use temperature range is-200 ℃ to 300 ℃. High insulation, low dielectric loss, high toughness, high strength and chemical corrosion resistance. As a special engineering material, the material has been widely used in the fields of aviation, aerospace, microelectronics, nanometer, liquid crystal, separation membrane, laser and the like. In the last 60 th century, various countries are listing the research, development and utilization of polyimides into one of the most promising engineering plastics in the 21 st century. Because of the outstanding characteristics of the material in terms of performance and synthesis, the great application prospect of the material is fully recognized as a structural material or a functional material.
Therefore, the dichlorine diphthalimide intermediate has important industrial value and significance as an imide monomer which is more beneficial to preparing polyimide and polyetherimide engineering plastics.
In addition, the imide monomer can be widely used for the mixing modification of other special engineering plastics. Such as polyphenylene sulfide, polyphenyl ether and other special engineering plastics with high performance. Polyphenylene Sulfide (PPS) has good mechanical properties and high temperature resistance, excellent flame retardancy, excellent chemical resistance, oil resistance, and the like, can be used as a substitute for many conventional thermosetting plastics or metal materials, and can withstand very severe high-temperature environments and mechanical loads. PPS and reinforced polyphenylene sulfide composite materials such as glass fibers, carbon nanotube graphene, and the like are widely used in electronics, automobiles, precision instruments, chemical industry, aerospace, and other wide industrial fields. If the dichloro diphthalimide intermediate is synthesized and purified and then is used in the polycondensation process of PPS, the PPS is subjected to chemical modification, and the obtained polyphenylene sulfide/polyimide copolymer has the excellent performances of polyphenylene sulfide and polyimide, so that the polyphenylene sulfide/polyimide copolymer has great market prospect and great technical advantage.
In the prior patents and reports, the synthesis of imide intermediates from chlorophthalic anhydride and diamine compounds is rarely reported. Patent CN 108164452A of scoliol chemical industry limited uses inert solvents such as paraffin, and no catalyst and dehydrating agent are added, and the intermediate of dichloro diphthalimide is synthesized from halogenated phthalic anhydride and diamine compound. The method has the advantages of no catalyst, slower reaction, lower yield, easy agglomeration of intermediate products or byproducts in the process and difficult dispersion in solvents such as paraffin. The reaction process is not easy to control.
The patent CN106232678A adopts solvents such as melted diphenyl sulfone, sulfolane and the like, and reacts the substituted phthalic anhydride with organic diamine to directly prepare the dichloro diphthalimide intermediate. The method does not need to add a catalyst, but the method has extremely strict requirements on the water content in a reaction system, and the water molecule content is required to be less than 100ppm, so that the method has extremely strict requirements on the realization of industrial production and equipment. And the product purification is also difficult.
Therefore, it is very necessary to develop a method which has simple reaction process, easy control of reaction, simple post-treatment and good product quality and is beneficial to industrialized production of the dichloro diphthalimide intermediate.
Disclosure of Invention
The invention solves the problems of low yield and difficult separation and purification in the process of producing the dichloro diphthalimide intermediate in the prior production technology. The synthesis process has the advantages of simple steps, convenient operation, easy control of reaction, safe process and suitability for industrial production.
In order to solve the problems, the invention adopts the following technical scheme:
a dichloro diphthalimide intermediate has a structural general formula:
wherein R in the general structural formula is different according to the difference of the selected diamine compound.
A synthesis method of a dichloro diphthalimide intermediate comprises the following steps:
reacting chlorophthalic anhydride and diamine compound in the presence of solvent, catalyst and dehydrating agent at 50-200 deg.c in nitrogen atmosphere for 5-20 hr, cooling and filtering after the reaction, re-crystallizing the filter cake, alcohol washing or water washing and filtering to obtain the dichloro diphthalimide intermediate.
Wherein the chlorophthalic anhydride is 3-chlorophthalic anhydride or 4-chlorophthalic anhydride or a mixture of 3-chlorophthalic anhydride and 4-chlorophthalic anhydride.
Diamine compounds useful in this synthetic process include, but are not limited to: diamine compounds such as p-phenylenediamine, m-phenylenediamine, ethylenediamine, 1, 3-propylenediamine, 1, 4-butylenediamine, 1, 6-hexamethylenediamine, 4-diaminodiphenyl ether, etc.
The molar ratio of the chlorophthalic anhydride to the diamine compound is 1.2-3:1, preferably 2-3:1, and more preferably 2-2.5:1. The solvent dosage is 3-20 times of the total mass of the chlorophthalic anhydride and the diamine compound.
In the invention, the specific implementation mode of the feeding process is as follows: the chlorophthalic anhydride is directly and completely added into the reaction system, the diamine compound can be directly and completely added into the reaction system, can be completely dissolved in the reaction solvent and added in batches or continuously added dropwise into the reaction system through a metering pump or an equilibrium feeder, can also be partially and directly added into the reaction system, and can be partially added in batches or continuously added dropwise into the reaction system through a metering pump or an equilibrium feeder.
In the invention, the solvent is liquid at normal temperature, and the boiling point is more than 150 ℃ and does not participate in the synthesis process of the imide intermediates, such as aprotic solvents of DMAc, DMF, NMP and the like; DMAc/HAc, NMP/HAc, DMAc/H 3 PO 4 And mixed solvents; acid solvents such as phosphoric acid. DMAc is preferred.
In the invention, the catalyst is an acid substance with high boiling point, such as sulfuric acid, phosphoric acid and the like; acids that form azeotropes with solvents, such as acetic acid, are also possible. The molar ratio of the added catalyst to the diamine compound is 0.01-0.1:1.
In the invention, the dehydrating agent is acetic anhydride, sulfur trioxide, phosphorus pentoxide and the like. The content of the added dehydrating agent is 0.5-2:1 of the molar ratio of the dehydrating agent to the diamine compound.
In the invention, the filtrate generated after the reaction system is filtered can be directly recycled to enter the synthesis of the next batch, and can also be subjected to recovery treatment of the solvent.
In the invention, the specific implementation mode of the synthesis process is as follows: the temperature of the reaction system is maintained between 50 and 200 ℃, nitrogen is always introduced into the system, and the reaction is carried out for 5 to 20 hours. After the reaction is completed, recrystallizing a filter cake obtained after suction filtration of the reaction system, and washing the obtained filter cake with alcohol or water after suction filtration. And then filtering and drying to obtain the product of the imide intermediate.
The product obtained by the invention can be used as imide monomer for preparing engineering plastics.
In the invention, the solvent used in the recrystallization process is a solvent which has a certain solubility to the product imide intermediate at a high temperature and has a lower solubility at a low temperature, and the solvent also has a better solubility to the diamine compound and the chlorophthalic anhydride at a low temperature. Solvents used include, but are not limited to, DMAc, DMF, NMP, acetonitrile, acetone, and the like. DMAc is preferred.
In the invention, the solvent used in the alcohol washing process is low-carbon alcohol such as methanol, ethanol and the like.
The reaction equation of the invention is:
in the method, the acid substances not only serve as catalysts to reduce the activation energy required by the reaction; and the acid environment provided well inhibits the reaction of the intermediate product polycondensation to generate polyamide.
The dehydrating agent used in the invention is preferably anhydride corresponding to the catalyst, and corresponding acid is further generated after dehydration so as to increase the content of the catalyst.
The system after the reaction is uniform solid suspension, and the content of the product dichloro diphthalimide which is still dissolved in the solvent after cooling is very low, thus being very beneficial to the filtration post-treatment of the system after the reaction. And recrystallizing the filtered filter cake with a solvent, and further purifying. The purified filter cake is subjected to solvent replacement by alcohol washing, so that the filter cake is convenient to dry and further dissolves unreacted raw materials, and the high purity of the product is ensured. The steps are simple and convenient, the operation is easy, the reaction filtrate, the recrystallization mother liquor and the alcohol washing filtrate can be fully recycled for a plurality of times, the process cost is greatly reduced, and the method is suitable for industrial production.
Drawings
FIG. 1 shows the results of IR detection of the product of example 1;
FIG. 2 shows the IR detection results of the product of example 2;
FIG. 3 shows the IR detection of the product of example 3.
Detailed Description
The present invention will be described in further detail with reference to the following specific examples, but the present invention is not limited to the following examples, and the implementation conditions adopted in the following examples may be further adjusted according to different requirements of specific applications, and the implementation conditions that are not specified are all other examples obtained by those skilled in the art without making any creative effort, and are all within the scope of protection of the present invention.
Example 1:
10.00 g of 3-chlorophthalic anhydride (0.0548 mol), 2.963 g of p-phenylenediamine (0.0274 mol), 200mL of DMAc (anhydrous), 0.049 g of 98% sulfuric acid, 0.9864 g of acetic anhydride were charged to a 500mL four-necked round bottom flask equipped with a stirring paddle. The flask was then fitted with a condenser and nitrogen fitting and purged with high flow nitrogen for several minutes to give N 2 Filling the flask interior. The nitrogen purge was maintained at a stirring speed of 300rpm, the temperature of the liquid in the flask was raised to 160℃using an oil bath, and the reaction was refluxed for 10 hours, and then cooled to room temperature. The reaction mixture was filtered under reduced pressure to give a crude product cake, and the filtrate was collected and used as the reaction solvent for the next batch. The crude product was transferred to another 500mL four-necked round bottom flask equipped with a stirrer, nitrogen tap and condenser, and 200mL of DMAc (anhydrous) was added, stirred well, heated to 160℃under nitrogen, refluxed for 1 hour, and then cooled to room temperature. The mixture was filtered under reduced pressure to give a DMAc reslurry cake, and the filtrate was collected and distilled under reduced pressure to recover DMAc. The reslurry filter cake was transferred to a 500mL three-necked round bottom flask equipped with stirring paddles and a condenser, and 200mL of absolute ethanol was added, stirred well, heated to 80 ℃, refluxed for 1 hour, and then cooled to room temperature. The mixture was filtered under reduced pressure to give an ethanol reslurry cake, and the filtrate was collected and distilled to recover ethanol. Transferring the ethanol reslurry filter cake to a surface dish, drying in a vacuum oven at 80deg.C and 90kPa to constant weight to obtain 11.205 g of pure product with a yield of 93.55%, and detecting purity by HPLC>99%. The results of IR detection of the product are shown in FIG. 1.
The IR detection results of the product of example 1 are shown in FIG. 1, and are located at 1777 cm to 1719cm -1 Carbonyl stretching vibration at-1357 cm -1 The C-N bond stretching vibration at the position is characteristic absorption of the imide ring. The presence of imide rings was demonstrated.
Example 2:
186.6 g of 4-chloro are reactedPhthalic anhydride (1.01 mol), 27.02 g of m-phenylenediamine (0.25 mol), 102.1 g of acetic anhydride (1.0 mol), 1200mL of DMAc (anhydrous), 1000mL of the previous batch of reaction filtrate, and 1.00 g of 98% sulfuric acid were charged into a 3000mL four-necked round bottom flask equipped with a stirring paddle. Another 27.02 g of m-phenylenediamine (0.25 mol) was dissolved in 300mL of DMAc (anhydrous) and charged into a 500mL balance feeder. The balance feeder was then mounted on the flask, and a condenser and nitrogen fitting were mounted on the flask, purged with high flow nitrogen for several minutes to allow N 2 Filling the flask interior. The nitrogen purge was maintained at a stirring speed of 240rpm, the temperature of the liquid in the flask was raised to 166℃using an oil bath, and then a m-phenylenediamine solution was slowly added dropwise thereto, and the reaction was refluxed for 10 hours, and then cooled to room temperature. The reaction mixture is filtered under reduced pressure to obtain a crude product filter cake, and the filtrate is recovered for recycling. Adding the crude product into DMAc and clear water in sequence, stirring, re-pulping, filtering, drying the filter cake in a vacuum oven at 100 ℃ and 85kPa vacuum degree to constant weight to obtain 207.5 g of pure product, obtaining the yield of 94.92%, and detecting the purity by HPLC>99%. The results of IR detection of the product are shown in FIG. 2.
The IR detection results of the product of example 2 are shown in FIG. 2, at 1774 cm to 1718cm -1 Carbonyl stretching vibration at-1357 cm -1 The C-N bond stretching vibration at the position is characteristic absorption of the imide ring. The presence of imide rings was demonstrated.
Example 3:
the m-phenylenediamine type dichlorophthalimide intermediate generated in the embodiment 2 is used for synthesizing polyimide thioether special engineering plastics. 14.01g of sodium hydrosulfide, 10.25g of sodium hydroxide, 7.5g of catalyst, 4.1g of auxiliary agent and 550g of solvent are taken, the raw materials are pre-dehydrated in an autoclave under the nitrogen protection atmosphere, 169g of m-phenylenediamine type dichlorophthalimide intermediate synthesized in the example 2 is added after most of water in the system is removed, a certain amount of solvent is added, and high-temperature polycondensation is carried out in the autoclave under the nitrogen protection atmosphere. And after the polycondensation reaction is finished, sequentially carrying out high-temperature sedimentation on the reaction slurry, re-pulping, washing with a solvent, and washing with water to obtain the refined polyimide thioether special functional plastic. 94.1g of the product is obtained, the yield is 94.57%, the particle shape is obtained, and the molecular weight of the high molecular product is more than 30000 measured by an intrinsic viscosity method. The results of IR detection of the product are shown in FIG. 3.
The IR detection results of the products of the application examples are shown in FIG. 3, at 1773 cm to 1715cm -1 The carbonyl stretching vibration at the position of 1362cm -1 The C-N bond stretching vibration at the position is characteristic absorption of the imide ring. The infrared characteristic absorption of the imide ring is satisfied.
Claims (1)
1. A synthesis method of a dichloro-diphthalimide intermediate, wherein the dichloro-diphthalimide intermediate has a structural general formula:
wherein R in the structural general formula is determined by diamine compounds selected to participate in synthesis;
the method is characterized by comprising the following steps of:
reacting chlorophthalic anhydride and diamine compound in the presence of solvent, catalyst and dehydrating agent at 50-200 deg.c in nitrogen atmosphere for 5-20 hr, cooling and filtering after the reaction, re-crystallizing the filter cake, alcohol washing or water washing and filtering to obtain dichloro diphthalimide intermediate;
the diamine compound is p-phenylenediamine and m-phenylenediamine;
the chlorophthalic anhydride is 3-chlorophthalic anhydride or 4-chlorophthalic anhydride or a mixture of 3-chlorophthalic anhydride and 4-chlorophthalic anhydride;
the catalyst is sulfuric acid;
the dehydrating agent is acetic anhydride;
the solvent is DMAc; the feeding mole ratio of the chlorophthalic anhydride to the diamine compound is 1.2-3:1, and the solvent dosage is 3-20 times of the total mass of the chlorophthalic anhydride and the diamine compound; the mol ratio of the added catalyst to the diamine compound is 0.01-0.1:1;
the molar ratio of the amount of the dehydrating agent to the diamine compound is 0.5-2:1.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101463132A (en) * | 2007-12-19 | 2009-06-24 | 中国科学院宁波材料技术与工程研究所 | Polythioether acid imide and preparation thereof |
| CN101538366A (en) * | 2009-04-28 | 2009-09-23 | 四川大学 | Polyarylene imide sulfide polymer and preparation method thereof |
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| CN101392055B (en) * | 2007-09-18 | 2011-08-03 | 中国科学院宁波材料技术与工程研究所 | Iso-poly(sulfide-imide) and preparation method thereof |
| CN108164452B (en) * | 2018-02-09 | 2019-06-18 | 苏州科尔力化工有限公司 | A kind of preparation method of bis- (chlorophthalimides) |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101463132A (en) * | 2007-12-19 | 2009-06-24 | 中国科学院宁波材料技术与工程研究所 | Polythioether acid imide and preparation thereof |
| CN101538366A (en) * | 2009-04-28 | 2009-09-23 | 四川大学 | Polyarylene imide sulfide polymer and preparation method thereof |
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