KR20150141839A - Preparation method of polyimide using water as a dispersion medium - Google Patents

Abstract

The present invention relates to a novel method for synthesizing polyimide and, more specifically, to a method for manufacturing polyimide by dispersing a dianhydride compound and a diamine compound in water and then reacting the same in a sealed pressure vessel under the condition of a temperature higher than 5°C with pressure. In the method for synthesizing polyimide in accordance with the present invention, water is used as a dispersion medium for the reaction, so no organic waste liquid is created. Therefore, the method has advantages of: being eco-friendly; low manufacturing costs; no decrease in physical properties due to a residual solvent by minimization of the residual solvent after drying; and lower reaction temperature, less reaction steps, and shorter reaction time than the conventional method. The manufactured polyimide has higher thermostability and molecular weight than polyimide manufactured by the conventional synthesis method.

Description

Preparation method of polyimide using water as a dispersion medium "

More particularly, the present invention relates to a process for producing a polyimide, which comprises using water as a dispersion medium to produce an organic solvent-free waste liquid, which is environmentally friendly, low in production cost, and capable of minimizing residual solvent after drying, To a process for producing a polyimide.

Polyimide and other highly heat-resistant polymer materials are essential materials for miniaturization, high performance, and high reliability of products in accordance with the development of advanced technology. They are used in the form of films, molded products, fibers, paints, adhesives and composites, / Electronics, automobiles and precision instruments. Among these films, they have been developed as electronic materials and packaging materials. If they are classified as such, general-purpose engineering plastic films mainly composed of polyester films, poly-urea resins having high heat resistance, excellent chemical resistance and electrical properties, A mid-film, an aramid film having high elasticity properties, a fluorine film, and a super engineering thermoplastic film. Among them, the film can be classified as a special film for various purposes depending on its heat resistance and usage. The use of these materials is steadily increasing with the development of the IT industry.

Among these materials, polyimide (PI) has excellent mechanical strength, chemical resistance, weather resistance and heat resistance based on the chemical stability of the imide ring. In addition, it is easy to synthesize, can form a thin film and does not need a crosslinking agent for curing. Due to its excellent electrical properties, it is widely regarded as a highly functional polymer material ranging from microelectronics and optical fields.

In recent years, weight reduction and miniaturization of products have been emphasized in the field of display, but the glass substrates currently used are heavy and broken, and continuous process is difficult. Therefore, a polyimide substrate having advantages of being light, flexible, and continuous process can be manufactured by replacing a glass substrate, and a surface protective material or base resin such as an insulating film or a protective coating of a semiconductor device, a flexible circuit substrate or an integrated circuit, But also in the case of forming an interlayer insulating film or a protective film of a circuit. In particular, when used as a coating material, a protective material to which a molded article such as a polyimide film is adhered with an adhesive, a liquid polyimide resin solution, or the like can be used.

There are four main methods of polyimide synthesis reported so far. As a first method, it is a general method composed of two steps of synthesizing polyamic acid (PAA) as a precursor by the reaction of dianhydride and diamine, and imidizing polyamic acid in the next step.

In the first step, the dianhydride is added to the reaction solution in which the diamine is dissolved as a step of preparing the polyamic acid, whereby the polyamic acid is formed due to the ring opening and the middle portion reaction. The reaction solvent to be used is N, N-dimethylacetamide, N, N-dimethylformamide, N-methylpyrrolidone, meta-polar organic solvent such as cresol are mainly used.

In the second step, the polyamic acid prepared in step 1 may be imidized by a chemical method or a dehydration and ring-closing reaction through a thermal method to form a polyimide.

The chemical imidization method is a method of adding a dehydrating agent represented by an acid anhydride such as acetic anhydride and a imidization catalyst represented by a tertiary amine such as pyridine to a polyamic acid solution which is a precursor. And is chemically imidized using a solvent which is easy to form hydrates such as pyridine, which is useful for the production of amorphous polyimide films. The thermal imidization method is the simplest method for thermally imidizing a polyamic acid solution, which is a precursor, by heating to 250 to 300 캜.

The fully aliphatic polyimide synthesized using the general polyimide synthesis method described above generally has a low molecular weight and thus has poor mechanical properties. In particular, when an aliphatic diamine is used, the basicity of the amino group of the diamine is high, so that the diamine does not participate in the polymerization reaction but forms a salt with the ammic acid, so that a high molecular weight polyimide can not be obtained.

The second method uses N - silylation reaction. In the first method, diamine and chlorotrimethylsilane are reacted with each other to prevent formation of salt to increase the molecular weight. The diamine protected by N - trimethylsilyl group is synthesized, The diamine is used to synthesize a polyimide. In this method, an organic solvent is used for the synthesis of the diamine protected by the N - trimethylsilyl group and for the polyimide synthesis.

N - chamber as a disadvantage of the correlation method is N - trimethylsilyl and the group difficulty in handling very sensitive to the expensive water price of the aliphatic diamine chloro trimethyl silane reagent for synthesizing min protect a number average molecular weight of the polyimide Is about 10,000, and the polyimide synthesis method has a disadvantage that it becomes more complicated than the general synthesis method.

The third method is a method of using meta-cresol as a solvent, in which meta-cresol is added as a solvent, dianhydride and diamine are added, and the temperature is increased stepwise to react for a long time.

The meta-cresol method has a long reaction time of more than 64 hours and a molecular weight that can not be satisfied with a number-average molecular weight of about 10,000. The meta-cresol solvent has a disadvantage that the drying time is long and the irritating odor is severe Lt; / RTI >

The fourth method is an in - situ method for solving the disadvantage that the N - seal relation method is moisture sensitive. After adding diamine to a reactor containing an organic solvent, chlorotrimethylsilane was added at a low temperature and then dianhydride was added to synthesize a polyamic acid protected with N - trimethylsilyl group. After removing the protecting group, the polyimide was passed through polyamic acid, .

In - situ The disadvantage of the yarn relation synthetic methods are long reaction times the molecular weight has not still satisfactory extent can has improved average molecular weight of 80,000 molecular weight, and chloro trimethyl silane reagent is expensive and has already the necessary and the drying time encoding the catalyst a long N - A reprecipitation process is required to synthesize a polyamic acid from which a protecting group has been removed from a polyamic acid protected with a trimethylsilyl group and a sufficient degree of transparency can not be secured even in the case of a battery cyclic polyimide.

With respect to the polyimide synthesis method using an organic solvent, the wholly aromatic polyimide synthesis method is High Performance Polymers , 15: 269-279, 2003 and High Performance Polymers , 18: 31-44, 2006. In this method, first, dianhydride is added to water and heated at a reflux temperature to hydrolyze tetracarboxylic acid. When diamine is added to this solution, salt precipitates of tetracarboxylic acid and diamine are formed. Thereafter, the mixture of the precipitate and water is transferred to a glass liner of a pressure device, air is taken out, and nitrogen is filled into the nitrogen atmosphere. Nitrogen is added to the mixture, the pressure is raised to 20 psi, and the mixture is heated at 135 ° C for 1 hour and 180 ° C for 2 hours. The resulting product is filtered and washed with water to obtain a powder, which is washed successively with hot water, methanol, acetone and dichloromethane. The obtained product is placed in a vacuum oven and heated at 40 DEG C overnight to obtain a polyimide powder. However, this method has a disadvantage in that it requires cumbersome synthesis steps and increases manufacturing cost.

Korean Registered Patent No. 1,004,096 Korea Patent No. 449,798 Korean Patent No. 0717377 U.S. Patent No. 7,053,168 International Patent Application No. 2012-091231 (WO2012 / 91231) International patent application PCT / JP2011 / 066144 (WO 2012/008543)

Polymer Science and Technology Vol. 24, No. 1, pp. 3-9, Park Jin-Young et al., Fabrication and Application of Polyimide-Based Particles Macromolecules 2002, 35, 2277-2281 Yasufumi Watanabe, Yoshimasa Sakai, Yuji Shibasaki, Shinji Ando, and Mitsuru Ueda Synthesis of Wholly Alicyclic Polyimides from N-Silylated Alicyclic Diamines and Alicyclic Dianhydrides Yoshiharu Terui, and Kazuhiko Maeda Synthesis of Fluorine-Containing wholly Alicyclic Polyimide by In Situ Silylation Method (in Japanese), Journal of photopolymer science and technology Volume 16, Number 2 (2003) Youshiyuki Oishi; Shu Ondera; Jan Oravec; Kunio Mori; Shinji Ando; Macromolecules 2009, 42, 5892-5894 Dulce M. Munoz, Mariola Calle, Jose G. de la Campa, Javier de Abajo, and Angel E. Lozano An Improved Method for Preparing Very High Molecular Weight Polyimides Macromolecular Research, Vol. 15, No. 2, pp 114-128 (2007) Anu Stella Mathews, Il Kim, and Chang-Sik Ha Synthesis, Characterization, and Properties of Fully Aliphatic Polyimides and Their Derivatives for Microelectronics and Optoelectronics Applications High Performance Polymers, 15: 269-279, 2003 John Chiefari, Buu Dao, Andrew M. Groth and Jonathan H. Hodgkin Water as Solvent in Polyimide Synthesis: Thermoset and Thermoplastic Examlpes High Performance Polymers, 18: 31-44, 2006 John Chiefari, Buu Dao, Andrew M. Groth and Jonathan H. Hodgkin Water as Solvent in Polyimides Synthesis II: Processable Aromatic Polyimide

In the present invention, a new manufacturing method using water as a dispersion medium is proposed to solve environmental pollution, increase in manufacturing cost, residual solvent, and the like caused by using an organic solvent in the conventional process for producing polyimide. The present invention also provides a novel method for manufacturing a polyimide which is significantly simpler than the conventional polyimide manufacturing method.

In addition, the present invention provides a polyimide having a high molecular weight as compared with a polymer produced by a conventional synthesis method, and having excellent mechanical properties and high thermal properties.

The present invention provides a process for producing a polyimide by dispersing a dianhydride compound and a diamine compound in water and then reacting the polyimide in a sealed pressure vessel under a temperature condition of 5 DEG C or higher and a pressure applied, Polyimide can be produced in a simple, inexpensive and environmentally friendly manner, and there is no problem of a residual solvent and a very high molecular weight as compared with the polyimide produced by a conventional synthetic method, so that polyimide having excellent mechanical properties and high thermal properties can be manufactured can do.

In the present invention, since water is used as a reaction dispersion medium in the production of polyimide, an organic waste solution is not generated, thus being environmentally friendly, low in production cost, minimized in residual solvent after drying, and there is no problem of deterioration of physical properties by residual solvent .

In addition, the present invention has the advantages of lowering the reaction temperature, lowering the reaction step and shortening the reaction time as compared with the conventional production method by applying pressure during the production of the polyimide. The polyimide thus produced has a polyimide , It has a high thermal stability and a high molecular weight. Further, there is an advantage that all of the fully aromatic polyimide, the partially aliphatic polyimide and the fully aliphatic polyimide can be produced.

1 is an FT-IR spectrum of pyromellitic dianhydride and 4,4'-oxydianiline polyimide according to Example 1.
2 is an FT-IR spectrum of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 4,4'-oxydianiline polyimide according to Example 2. Fig.
3 is an FT-IR spectrum of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 4,4-methylenebis (2-methylcyclohexylamine) polyimide according to Example 3.
4 is a graph showing the FT-IR spectra of 1,2,3,4-cyclopentane-tetracarboxylic dianhydride and 3- (aminomethyl) -3,5,5-trimethylcyclohexaneamine polyimide according to Comparative Example 1 to be.
5 shows the FT-IR spectra of 3- (aminomethyl) -3,5,5-trimethylcyclohexaneamine and 3- (aminomethyl) -3,5,5-trimethylcyclohexaneamine polyimide according to Comparative Example 2 to be.
6 shows the FT-IR spectra of 3- (aminomethyl) -3,5,5-trimethylcyclohexaneamine and 3- (aminomethyl) -3,5,5-trimethylcyclohexaneamine polyimide according to Comparative Example 3 to be.
7 is a graph showing the FT-IR spectrum of 1,2,3,4-cyclopentane-tetracarboxylic dianhydride and 3- (aminomethyl) -3,5,5-trimethylcyclohexaneamine polyimide according to Comparative Example 4 to be.

The present invention relates to a process for producing a polyimide by dispersing a dianhydride compound and a diamine compound in water, placing the mixture in a sealed pressure vessel and reacting the mixture under pressure at a reaction temperature in the range of 5 to 400 캜, Meade. ≪ / RTI >

More particularly, the present invention relates to a process for preparing a dianhydride compound, comprising: a) dispersing a dianhydride compound and a diamine compound in water; And b) placing the dispersion in a sealed pressure vessel and reacting the dianhydride compound and the diamine compound at a temperature of 5 to 400 캜 and under a pressure condition.

In one embodiment according to the present invention, the polyimide prepared according to the process may be a fully aromatic polyimide, a partially aliphatic polyimide or a fully aliphatic polyimide.

The dianhydride compounds that can be used in the present invention are substituted or unsubstituted aromatic or aliphatic dianhydride compounds.

In an embodiment of the present invention, substituted or unsubstituted aromatic or aliphatic dianhydrides represented by the following formula (1) may be used as the dianhydride.

≪ Formula 1 >

In the general formula 1 R ₁ is

≪ / RTI >

In one embodiment according to the present invention, the dianhydride compound may use one or more dianhydrides.

In one embodiment according to the present invention, the diamines may be substituted or unsubstituted aromatic or aliphatic diamines.

In one embodiment according to the present invention, the diamine may be a substituted or unsubstituted aromatic or aliphatic diamine represented by the following formula (2).

(2)

It is in Formula ₂ R 2,

≪ / RTI >

In one embodiment of the present invention, one or more diamines may be used as the diamine compound.

In one embodiment of the present invention, water may be used in any state of water, such as distilled water, deionized water, tap water or the like.

In one embodiment according to the present invention, the reaction temperature is preferably in the range of from 5 캜 to 400 캜. More specifically from 20 캜 to 250 캜. When the reaction temperature is lower than 5 ° C, the reaction rate is too slow to produce polyimide. When the temperature is higher than 400 ° C, thermal decomposition of monomers or polymers may occur.

In one embodiment according to the present invention, the reaction time of step b) preferably ranges from 5 minutes to 5 days. More specifically 10 minutes to 10 hours, more particularly 10 minutes to 5 hours. When the reaction time is less than 5 minutes, the reaction does not proceed well. If the reaction time is more than 5 days, hydrolysis of the polymer may occur.

In one embodiment according to the present invention, the pressing conditions of step b) preferably have a range of from 1 bar to 1000 bar. More specifically from 1 bar to 500 bar. If the reaction pressure is less than 1 bar, the reaction does not proceed well. If the reaction pressure is more than 1000 bar, the reaction vessel may be damaged.

In one aspect of the present invention, the method of pressurizing is configured in one or more ways selected from the group consisting of forming a water vapor pressure inside the pressure vessel, injecting an inert gas into the pressure vessel, or compressing the pressure vessel do. Wherein the inert gas is at least one gas selected from the group consisting of nitrogen, argon, helium, neon, krypton and xenon.

In one embodiment according to the present invention, the reaction product of step b) may be further filtered and dried to obtain a polyimide.

In another embodiment according to the present invention, there is provided a polyimide film prepared by dissolving polyimide prepared according to the above method in an organic solvent and applying the solution to a substrate. Examples of the organic solvent include N -methylpyrrolidone, N, N -dimethylacetamide, N, N -dimethylformamide, N -vinylpyrrolidone, N -methylcaprolactam, dimethylsulfoxide, tetra But are not limited to, methyl urea, pyridine, dimethylsulfone, hexamethylsulfoxide, meta-cresol, gamma-butyrolactone, ethylcellosolve, butylcellosolve, ethylcarbitol, butylcarbitol, ethylcarbitol acetate, butylcarbitol acetate , Ethylene glycol, ethyl lactate, butyl lactate, cyclohexanone, and cyclopentanone may be used. Also, here, the concentration of the polyimide in the solution may be 1 to 90 wt%. If the polyimide solution is difficult to prepare because of low solubility of the polyimide, the polyamic acid is dissolved in an organic solvent and applied to a substrate, followed by thermal imidization to produce a polyimide film.

In an embodiment of the present invention, a small amount of an additive such as a wettability improver may be added to the polyimide or polyamic acid solution if necessary. The additive is preferably added in an amount of 0.001 to 5 wt% based on the polyimide or polyamic acid. More specifically, 0.01 to 2% by weight may be added.

In one embodiment of the present invention, the method of applying the polyimide or polyamic acid composition for forming the polyimide film may be a spin coating method, a dipping method, a flexographic printing method, an inkjet printing method, a spraying method, A printing method and the like can be used. Among these methods, a bar coating method, a slit coating method, a screen printing method, a spin coating method and the like are preferable as a method for obtaining a thick film of 10 탆 or more.

According to another aspect of the present invention, there is provided a molded article produced by compression molding, injection molding, slush molding, blow molding, extrusion molding or spinning of a polyimide produced by the above method.

The polyimide synthesized by the production method of the present invention can be used in a wide range of industries including space, aviation, electric / electronic, semiconductor, transparent / flexible display, liquid crystal alignment film, automobile, precision instrument, packaging, medical material, separator, fuel cell, Can be used in the field.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples. It should be understood, however, that the following examples and experimental examples are provided to aid understanding of the present invention and are not intended to limit the scope of the present invention thereto.

Example  1-1: Wholly aromatic  Production of polyimide

22.6 g of pyromellitic dianhydride and 21.13 g of 4,4'-oxydianiline were dispersed in 200 mL of distilled water. The reaction solution was transferred to a 500-mL pressure vessel equipped with a stirrer, a nitrogen inlet, and a temperature controller. The air in the pressure vessel was replaced with nitrogen gas, and the temperature was adjusted to 135 ° C. The mixture was stirred at a pressure of 60 bar for 3 hours, Meade were synthesized.

In the infrared absorption spectrum (Fig. 1) of the synthesized polymer 1775 cm ^- an absorption band of the CN has already been deugi from C = O absorption band of deugi, 1367 cm ^-1 and 1715 cm ^-1 were observed in the ^first.

Example  1-2. Wholly aromatic  Production of polyimide

11.106 g of 4,4 '- (hexafluoroisopropylidene) dianiline and 8.005 g of 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl were dispersed in 200 mL of distilled water. The reaction solution was transferred to a 500-mL pressure vessel equipped with a stirrer, a nitrogen inlet, and a temperature controller. The air in the pressure vessel was replaced with nitrogen gas, and the temperature was adjusted to 135 ° C. The mixture was stirred at a pressure of 60 bar for 3 hours, Meade were synthesized.

In the infrared absorption spectrum of the polymer synthesized 1780 cm ^- an absorption band of the CN has already been deugi from C = O absorption band of deugi, 1369 cm ^-1 and 1718 cm ^-1 were observed in the ^first.

Example  2-1: Partial alicyclic  Production of polyimide

5.604 g of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 5.006 g of 4,4'-oxydianiline were dispersed in 200 mL of distilled water. The reaction solution was transferred to a 500-mL pressure vessel equipped with a stirrer, a nitrogen inlet, and a temperature controller. The air in the pressure vessel was replaced with nitrogen gas, and the temperature was adjusted to 135 ° C. The mixture was stirred at a pressure of 60 bar for 3 hours, Meade were synthesized.

Infrared absorption spectrum (Fig. 2) in 1778 cm of the composite ^polymer-1 and 1716 cm ^-1 in the image on the deugi C = O absorption band, already CN absorption band of deugi at 1365 cm ^-1 was observed.

Example  2-2: Partial alicyclic  Production of polyimide

8.3565 g of 4,4 '- (hexafluoroisopropylidene) dianiline and 5.604 g of 4,4'-oxydianiline were added to 200 mL of distilled water and dispersed. The reaction solution was transferred to a 500-mL pressure vessel equipped with a stirrer, a nitrogen inlet, and a temperature controller. The air in the pressure vessel was replaced with nitrogen gas, and the temperature was adjusted to 135 ° C. The mixture was stirred at a pressure of 60 bar for 3 hours, Meade were synthesized.

1779 cm in the infrared absorption spectrum of the synthesized ^polymer in the already deugi the C = O absorption band, 1362 cm ^-1 and 1718 cm ^-1 in the ^first absorption band of the CN has already deugi was observed.

Example  2-3: Partial alicyclic  Production of polyimide

5.604 g of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 5.006 g of 4,4'-oxydianiline were dispersed in 200 mL of distilled water. The reaction solution was transferred to a 500-mL pressure vessel equipped with a stirrer, a nitrogen inlet, and a temperature controller. The air in the pressure vessel was replaced with nitrogen gas and the temperature was adjusted to 180 ° C. The mixture was stirred at a pressure of 100 bar for 10 minutes, Meade were synthesized.

In the infrared absorption spectrum of the polymer synthesized 1778 cm ^{- 1} In the already deugi of the C = O absorption band, 1365 cm ^-1 from 1714 cm ^-1 The absorption band of CN already deugi was observed.

Example  2-4: Partial alicyclic  Production of polyimide

5.604 g of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 5.006 g of 4,4'-oxydianiline were dispersed in 200 mL of distilled water. The reaction solution was transferred to a 500-mL pressure vessel equipped with a stirrer, a nitrogen inlet, and a temperature controller. The air in the pressure vessel was replaced with nitrogen gas and the temperature was adjusted to 50 ° C. Meade were synthesized.

In the infrared absorption spectrum of the polymer synthesized 1776 cm ^- an absorption band of the CN has already been deugi from C = O absorption band of deugi, 1364 cm ^-1 and 1716 cm ^-1 were observed in the ^first.

Example  2-5: Partial alicyclic  Production of polyimide

5.604 g of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 5.006 g of 4,4'-oxydianiline were dispersed in 200 mL of distilled water. The reaction solution was transferred to a 500-mL pressure vessel equipped with a stirrer, a nitrogen injector and a temperature controller, and a high-pressure nitrogen gas was injected into the pressure vessel to form a pressure of 50 bar. The temperature was adjusted to 10 ° C, To synthesize polyimide.

In the infrared absorption spectrum of the polymer synthesized 1775 cm ^- an absorption band of the CN has already been deugi deugi in the C = O absorption band, 1364 cm ^-1 and 1717 cm ^-1 were observed in the ^first.

Example  3: Preparation of battery cyclic polyimide

5.9605 g of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 5.604 g of 4,4-methylenebis (2-methylcyclohexylamine) MMCA were added to 200 mL of distilled water and dispersed. The reaction solution was transferred to a 500-mL pressure vessel equipped with a stirrer, a nitrogen inlet, and a temperature controller. The air in the pressure vessel was replaced with nitrogen gas, and the temperature was adjusted to 135 ° C. The mixture was stirred at a pressure of 60 bar for 3 hours, Meade were synthesized.

In the infrared absorption spectrum (Fig. 3) of a synthetic polymeric 1773 cm ^- an absorption band of the CN has already been deugi deugi in the C = O absorption band, 1368 cm ^-1 and 1712 cm ^-1 it was observed in the ^first.

Example  4: Production of thin film of polyimide

Prior to the production of the thin film, a cleaning process of a silicon wafer to be used as a substrate was carried out. This process removes various contaminants such as particles, organic contaminants, metal contaminants, and natural oxide films. The contaminants were removed by heating at 120 ° C for 3 hours using a Piranha solution containing sulfuric acid and hydrogen peroxide in a ratio of 7: 3.

Then, 0.20 g of the synthesized polyimide was dissolved in 2.0 mL of N, N -dimethylacetamide or N, N -dimethylformamide, filtered through a fine filter having a pore size of 0.2 μm, and dried at 500 rpm 10 seconds and 1500 rpm for 50 seconds, followed by annealing after removing the solvent. Thus, a battery cyclic polyimide thin film was prepared. The polyimide solution was cast on a cleaned substrate, and then subjected to solvent removal and annealing to produce a battery cyclic polyimide thin film.

Comparative Example  1: Two-step preparation of battery cyclic polyimide

10 mL of N -methyl-2-pyrrolidone was added to a 50-mL 2-neck round bottom flask substituted with nitrogen gas, and 4.2028 g (2.00 mmol) of 1,2,3,4-cyclopentane-tetracarboxylic dianhydride was added thereto, And 3.406 g (2.00 mmol) of 3- (aminomethyl) -3,5,5-trimethylcyclohexaneamine were added thereto, followed by reaction at room temperature for 24 hours.

As a chemical imidization method, 5 mL of acetic anhydride and 3 mL of pyridine were added to this solution, refluxed at 170 ° C. for 5 hours, cooled to room temperature, and reprecipitated using an excessive amount of ice water. And washed with 100 mL of water and 100 mL of methyl alcohol, followed by vacuum drying to synthesize a battery cyclic polyimide.

As the thermal imidation method, polyimide was obtained by heating the synthesized polyamic acid solution at 250 to 300 ° C in an oven or hot plate stepwise and heating for 12 hours.

In the infrared absorption spectrum (Fig. 4) of the synthesized polymer 1774 cm ^{- 1} and 1713 cm ^- an absorption band of the CN already deugi from C = O absorption band, 1368 cm ^-1 of ^1-2 imide group was observed.

Comparative Example  2: Preparation of battery cyclic polyimide N - Thread relations  Manufacturing by method

To prepare an aliphatic diaminopolysiloxane, 25 mL of purified toluene was added to a 100 mL three-neck round bottom flask substituted with nitrogen gas, and 8.515 g (5.00 g) of 3- (aminomethyl) -3,5,5-trimethylcyclohexaneamine mmol) and 1.0864 g (10.0 mmol) of chlorotrimethylsilane were placed and reacted at 5 DEG C for 30 minutes. 0.5911 g (10.0 mmol) of trimethylamine was slowly added dropwise to this solution. After reacting at 5 ° C for 2 hours, the temperature was raised to 60 ° C, reacted for 24 hours, and vacuum dried to synthesize an aliphatic diaminopolysiloxane.

10 mL of N -methyl-2-pyrrolidone was added to a 50-mL 2-neck round bottom flask substituted with nitrogen gas, and 4.2028 g (2.00 mmol) of 1,2,3,4-cyclopentane-tetracarboxylic dianhydride was added thereto, And the aliphatic diaminopolysiloxane synthesized above (2.00 mmol) were added thereto, followed by reaction at room temperature for 24 hours.

The synthesized polyimide-siloxane was reprecipitated using distilled water. After filtration and vacuum drying, polyamic acid was synthesized.

As a chemical imidization method, 5 mL of acetic anhydride and 3 mL of pyridine were added to this solution, refluxed at 170 ° C. for 5 hours, cooled to room temperature, and reprecipitated using an excessive amount of ice water. And washed with 100 mL of water and 100 mL of methyl alcohol, followed by vacuum drying to synthesize a battery cyclic polyimide.

As the thermal imidation method, a polyimide was obtained by heating the synthesized polyamic acid solution at 250 to 300 ° C in an oven or a hot plate stepwise and heating for 12 hours.

Infrared absorption spectrum (Fig. 5) in 1778 cm of the composite ^polymer-1 and 1714 cm ^-1 in the image on the deugi C = O absorption band, already CN absorption band of deugi at 1368 cm ^-1 was observed.

Comparative Example  3: Battery of cyclic polyimide in - situ Thread relations  Manufacturing by method

10 mL of N -methyl-2-pyrrolidone (NMP) was added to a 50-mL 2-necked round bottom flask substituted with nitrogen gas, and 3.406 g of 3- (aminomethyl) -3,5,5-trimethylcyclohexaneamine 2.00 mmol) was added thereto, and 0.43456 g (4.0 mmol) of chlorotrimethylsilane was added thereto at 0 ° C, followed by stirring for 2 hours. Then, 4.2028 g (2.00 mmol) of 1,2,3,4-cyclopentane-tetracarboxylic dianhydride was added thereto and reacted at room temperature for 24 hours. The synthesized diaminopolysiloxane was reprecipitated using distilled water. After filtration and vacuum drying, polyamic acid was synthesized.

The chemical imidization furnace was prepared by adding 5 mL of acetic anhydride and 3 mL of pyridine to the solution, refluxing the mixture at 170 ° C. for 5 hours, reducing the temperature to room temperature, and reprecipitating the mixture using an excess of ice water. And washed with 100 mL of water and 100 mL of methyl alcohol, followed by vacuum drying to synthesize a battery cyclic polyimide.

As the thermal imidation method, a polyimide was obtained by heating the synthesized polyamic acid solution at 250 to 300 ° C in an oven or a hot plate stepwise and heating for 12 hours.

In the infrared absorption spectrum (Fig. 6) of the synthesized polymer 1776 cm ^- an absorption band of the CN has already been deugi from C = O absorption band of deugi, 1367 cm ^-1 and 1714 cm ^-1 were observed in the ^first.

Comparative Example  4: Battery of cyclic polyimide Meta - Preparation by cresol synthesis method

10 mL of meta-cresol was added to a 50 mL-2-necked round bottom flask substituted with nitrogen gas, and 4.2028 g (2.00 mmol) of 1,2,3,4-cyclopentane-tetracarboxylic dianhydride and 3- (aminomethyl ) -3,5,5-trimethylcyclohexaneamine (3.406 g, 2.00 mmol) were added and reacted at 100 ° C for 12 hours at 150 ° C for 4 hours and at 200 ° C for 48 hours. The synthesized solution was cooled to room temperature, washed with 100 mL of methacresol and 100 mL of methyl alcohol, filtered and vacuum dried at 60 ° C. to synthesize a battery cyclic polyimide.

In the infrared absorption spectrum (Fig. 7) of the synthesized polymer 1773 cm ^- an absorption band of the CN has already been deugi deugi in the C = O absorption band, 1367 cm ^-1 and 1712 cm ^-1 were observed in the ^first.

As shown in Table 1, in Examples 1 to 3 of the present invention, the maximum imidization temperature is low, the reaction time is short, and the reaction step is small as compared with Comparative Examples 1 to 4 which are conventional methods. In addition, there is an advantage that the reaction proceeds in water without using a catalyst and an organic solvent. It was confirmed that the polyimides synthesized in Examples 1 to 3 had higher pyrolysis temperatures and higher molecular weights than the polyimides synthesized in Comparative Examples 1 to 4.

Therefore, the polyimide synthesizing method of the present invention is simpler and more environmentally friendly than the conventional method, and the polyimide synthesized by the method of the present invention has a higher molecular weight than the polyimide produced by the conventional synthetic method, It has thermal properties.

Claims (23)

a) dispersing the dianhydride compound and the diamine compound in water; And b) placing the dispersion in a sealed pressure vessel and reacting the dianhydride compound and the diamine compound at a temperature of 5 to 400 캜 and under a pressure condition.
The method according to claim 1,
Wherein the polyimide is a wholly aromatic polyimide, a partial alicyclic polyimide or a battery cyclic polyimide.
The method according to claim 1,
Wherein the dianhydride compound is a substituted or unsubstituted aromatic or aliphatic dianhydride.
The method of claim 3,
Wherein the substituted or unsubstituted aromatic or aliphatic dianhydride is a dianhydride of formula (1): < EMI ID =
&Lt; Formula 1 &gt;

Wherein R &lt; ₁ &gt;

&Lt; / RTI &gt;
The method according to claim 1,
Wherein the dianhydride compound is one or more than one dianhydride.
The method according to claim 1,
Wherein the diamine compound is a substituted or unsubstituted aromatic or aliphatic diamine.
The method according to claim 6,
Wherein the substituted or unsubstituted aromatic or aliphatic diamine is a diamine of formula (2): < EMI ID =
(2)

Here, R ₂ is

&Lt; / RTI &gt;
The method according to claim 1,
Wherein the diamine compound is one or more diamines.
The method according to claim 1,
and the reaction of step (b) is carried out at a temperature of 20 ° C to 250 ° C.
The method according to claim 1,
and the reaction of step b) is carried out for 5 minutes to 5 days.
The method according to claim 1,
and the reaction of step b) is carried out for 10 minutes to 10 hours.
The method according to claim 1,
and the reaction of step b) is carried out for 10 minutes to 5 hours.
The method according to claim 1,
and the pressure condition of step (b) is a pressure condition in the range of 1 bar to 1000 bar.
The method according to claim 1,
and the step b) is a pressure condition in the range of 1 bar to 500 bar.
The method according to claim 1,
Wherein the pressurizing condition is one or two or more selected from the group consisting of forming a water vapor pressure inside the pressure vessel, injecting an inert gas into the pressure vessel, or compressing the pressure vessel .
16. The method of claim 15,
Wherein the inert gas is at least one gas selected from the group consisting of nitrogen, argon, helium, neon, krypton, and xenon.
The method according to claim 1,
further comprising, after step b), filtering and drying the reaction product of step b) to obtain a polyimide.
17. A polyimide prepared according to the process of any one of claims 1 to 17.
Dissolving the polyimide according to claim 18 in an organic solvent to prepare a solution; And
And applying the solution to a substrate.
20. The method of claim 19,
Organic solvents, N - methylpyrrolidone, N, N - dimethyl acetamide, N, N - dimethyl-formamide, N - vinyl pyrrolidone, N - methyl caprolactam, dimethyl sulfoxide, tetramethylurea, But are not limited to, pyridine, dimethyl sulfone, hexamethyl sulfoxide, meta-cresol, gamma-butyrolactone, ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, butyl carbitol acetate, , Ethyl lactate, butyl lactate, cyclohexanone, and cyclopentanone. &Lt; RTI ID = 0.0 &gt; 8. &lt; / RTI &gt;
20. The method of claim 19,
Wherein the concentration of the polyimide in the solution is 1 to 90 wt%.
22. A polyimide film produced according to the method of any one of claims 19 to 21.
A molded product obtained by molding the polyimide according to claim 18 by a method selected from the group consisting of compression molding, injection molding, slush molding, blow molding, extrusion molding and spinning.

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