JPH11140184A - Novel polyimide precursor, polyimide and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyimide excellent in heat resistance and processability by reacting a dicyclohexyl-2,3,3',4-tetracarboxylic acid compd. or a diester or dianhydride thereof with a diamine. SOLUTION: One mol of a dicyclohexyl-2,3,3',4-tetracarboxylic acid compd. or a diester or dianhydride thereof is added to, stirred with, and reacted with 0.95-1.05 mol of a diamine of the formula: H2 N-R2 -NH2 dissolved in an aprotic solvent (e.g. N-methyl-2-pyrrolidone) to give a polyimide precursor comprising a polyamic acid or an ester thereof having structural units represented by formulas I to IV. The precursor is subjected to ring closure by dehydration or dealcoholation to give a polyimide. p-Phenylenediamine, 4,4'-diaminodiphenyl ether, and 1,2-bis(4-aminophenoxy)ethane are examples of the diamine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyimide precursor which is a novel polyamic acid or a polyamic acid ester, a method for producing the same, and a novel polyimide and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a polyimide using an aromatic tetracarboxylic anhydride as a tetracarboxylic acid component has high heat resistance but poor processability and is colored.
It is not soluble in solvents and cannot be used for some applications that require high transparency and solubility in solvents. On the other hand, 1, 2,
3,4-butanetetracarboxylic dianhydride and 1,2,2
A polyimide using an aliphatic tetracarboxylic acid such as 4,5-cyclohexanetetracarboxylic dianhydride or an alicyclic tetracarboxylic acid as a tetracarboxylic acid component is not practical because it has extremely low heat resistance and is brittle.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyimide having heat resistance and excellent processability, transparency, solvent solubility, and polymer phase solubility, a precursor thereof, and a method for producing the same. To provide.

[0004]

That is, the present invention provides:
The following general formula [1], [2], [3] or [4]

[0005]

Embedded image

(Wherein, R ₁ represents a hydrogen atom or a monovalent hydrocarbon group, R ₂ represents a divalent hydrocarbon group, and m represents an integer.) The present invention relates to a polyimide precursor which is a polyamic acid or a polyamic acid ester. The present invention also relates to dicyclohexyl-
2,3,3 ', 4'-tetracarboxylic acid, its diester or its dianhydride and the following general formula [5]

[0007]

Embedded image

Wherein R ₂ represents a divalent hydrocarbon group. A process for producing a polyimide precursor as the above-mentioned polyamic acid or polyamic acid ester, characterized by reacting with a diamine represented by the formula: About. Further, the present invention provides the following general formula [6]

[0009]

Embedded image

(Wherein R ₂ represents a divalent hydrocarbon group;
m represents an integer. The present invention relates to a polyimide having a structural unit represented by the formula: Further, the present invention relates to a method for producing a polyimide, characterized in that the polyimide precursor is subjected to a dehydration or dealcohol reaction to effect ring closure.

The dicyclohexyl-2,3,3 ', 4'-tetracarboxylic acid compound (acid,
Acid diesters, acid dianhydrides) include dicyclohexyl-2,3,3 ', 4'-tetracarboxylic acid, dicyclohexyl-2,3,3', 4'-tetracarboxylic acid methyl ester, dicyclohexyl-2,3 , 3 ', 4'-
Tetracarboxylic acid ethyl ester, dicyclohexyl-
2,3,3 ′, 4′-tetracarboxylic acid propyl ester, dicyclohexyl-2,3,3 ′, 4′-tetracarboxylic acid butyl ester, dicyclohexyl-2,3
3 ', 4'-tetracarboxylic dianhydride and the like can be mentioned.

The above-mentioned dicyclohexyl-2,3,3 ',
The 4′-tetracarboxylic acid compound is, for example, biphenyl-
2,3,3 ', 4'-Tetracarboxylic acid alkyl ester is dissolved in a solvent, a hydrogenation reaction is carried out in the presence of a hydrogenation catalyst, and hydrolysis is carried out to give dicyclohexyl-2,3,2.
3 ', 4'-Tetracarboxylic acid is obtained, and in the case of diester, it is reacted with alcohol to form a half ester, and dianhydride dehydrates dicyclohexyl-2,3,3', 4'-tetracarboxylic acid. It can be obtained by ring closure and dehydration.

The above-mentioned biphenyl-2,3,3 ', 4'-
The tetracarboxylic acid alkyl ester is a known compound, for example, Japanese Patent Publication No. 60-33379, Japanese Patent Publication No.
It can be produced by the method described in 1-57821. For example, a phthalic acid diester is subjected to a coupling reaction in the presence of oxygen using a catalyst of oxygen, a palladium salt and 1,10-phenanthroline or bipyridyl, and then formed biphenyl-2,3,3 ′, 4′-methyl tetracarboxylate After removing a catalyst and a solvent from a mixture containing an alkyl ester such as an ester, the mixture can be obtained by a distillation method.

The dicyclohexyl-2,3,3 ', 4'-tetracarboxylic acid compound used in the present invention can be preferably produced as follows. That is, the above-mentioned biphenyl-2,3,3 ', 4'-tetracarboxylic acid ester is dissolved in a solvent such as an alcohol or an ester and the hydrogenation reaction is carried out in the presence of a hydrogenation catalyst such as a noble metal powder or a supported catalyst thereof. Is performed. When the reaction is completed, the catalyst is removed from the reaction mixture by a filtration operation,
The system is further reduced in pressure to remove the solvent, followed by distillation under reduced pressure to obtain dicyclohexyl-2,3,3 ', 4'-tetracarboxylic acid ester. Then, the aforementioned dicyclohexyl-
2,3,3 ′, 4′-Tetracarboxylic acid ester is hydrolyzed by a heat hydrolysis method, an acid hydrolysis method or an alkali hydrolysis method to obtain dicyclohexyl-2,3.
3 ', 4'-Tetracarboxylic acid is obtained. Furthermore, dicyclohexyl-2,3,3 ', 4'-tetracarboxylic dianhydride can be obtained by heating dicyclohexyl-2,3,3', 4'-tetracarboxylic acid to dehydrate it and deactivate it by ring closure. Can be. Also, dicyclohexyl-2,3,
The 3 ', 4'-tetracarboxylic diester is reacted with dicyclohexyl-2,3,3', 4'-tetracarboxylic dianhydride and an alcohol such as methanol to form a half ester (diester). Can be obtained.

As the diamine represented by the general formula [5] in the present invention, an aromatic diamine is preferable, but an aliphatic diamine, an alicyclic diamine or diaminopolysiloxane can be used. Examples of the diamine include para-phenylenediamine, meta-phenylenediamine, 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, and 4,4′-
Diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfide, 2,2-bis (4-aminophenoxyphenyl) propane, 4,4'-bis (3-aminophenoxy) phenylsulfone, 1,2-bis (4- Aminophenoxy) ethane, bis [2- (4-aminophenoxy) ethyl] ether, 1,2-bis [2- (4-aminophenoxy) ethoxy] ethane, bis [2- (2-
(4-aminophenoxy) ethoxy] ethyl ether,
1,5-naphthalenediamine, 4,4′-diaminodiphenylether-3-sulfonamide, 3,4′-diaminodiphenylether-4-sulfonamide, 3,
4'-diaminodiphenylether-4-sulfonamide, 3,4'-diaminodiphenylether-3'-sulfonamide, 3,3'-diaminodiphenylether-4-sulfonamide, 4,4 '-Diaminodiphenylmethane-3-sulfonamide, 3,4'-diaminodiphenylmethane-4-sulfonamide, 4,4'-diaminodiphenylether-3-carbonamide, 3,4'
-Diaminozophenyl ether-4-carbonamide,
3,4'-diaminodiphenylether-4-carbonamide, 3,4'-diaminodiphenylether-3 '
-Carbonamide, 4,4'-diaminodiphenylmethane-3-carbonamide, 3,3'-diaminodiphenylmethane-4-carbonamide, hexamethylenediamine, octamethylenediamine, 1,4-diaminocyclohexane, the number of siloxane bonds is 3 The diaminopolysiloxane containing a methyl group or a phenyl group at -75 is exemplified.

The novel polyimide precursor of the present invention comprises a dicyclohexyl-2,3,3 ', 4'-tetracarboxylic acid compound and a diamine, preferably in an inert aprotic polar solvent, in a solvent. It can be obtained by reacting in a solvent. This dicyclohexyl-2,
The ratio of the 3,3 ′, 4′-tetracarboxylic acid compound to the diamine is dicyclohexyl-2,3,3 ′,
The diamine is 0.95-1.05, particularly 0.98-1. It is preferably O2. Examples of the aprotic polar solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide,
N-vinylpyrrolidone and the like can be mentioned. In carrying out the above method preferably, the diamine is dissolved in an inert aprotic polar solvent, and then dicyclohexyl-2,3,3 ′, 4′-tetracarboxylic dianhydride is added. What is necessary is just to stir. The reaction proceeds rapidly, the viscosity of the reaction mixture gradually increases, and polyamic acid is generated.

[0017] Alternatively, the novel polyimide precursor of the present invention can be obtained by converting the carboxylic acid group of the polyamic acid obtained by the above-mentioned method into metal, ethanol or isopropanol.
And esterification by reacting with alcohols such as toluene and normal propanol, and dicyclohexyl-2,3
The 3 ', 4'-tetracarboxylic dianhydride can be obtained by a method in which a ring-opened diesterified 3', 4'-tetracarboxylic dianhydride is reacted with a diamine compound in a solvent.

The polyimide precursor of the present invention is prepared by preparing a polyimide precursor solution dissolved in the aprotic polar solvent or dioxane, ethylene glycol-n-butyl ether, ethylene glycol monoethyl ether, or the like. It can be used as a varnish for coatings or as a varnish for coatings such as ceramic substrates or conductive substrates. The varnish preferably has a polyimide precursor concentration of about 5 to 50% by weight. The polyimide of the present invention can be used as a film or a polyimide film.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments.
In addition, the physical properties of the polyimide film were evaluated as follows. (1) Using a transmittance spectrophotometer (U-3000 spectrophotometer type double beam spectrophotometer manufactured by Hitachi, Ltd.)
Wavelength 700nm, 600nm, 500nm, 400nm
Was measured for visible light transmittance. (2) Glass transition temperature (Tg) Using a dynamic viscoelasticity measuring device (RSA2 manufactured by Rheometric Scientific), the film was 5 m wide.
m, 25 mm in length, measured at a gripping interval of 22 mm, at a frequency of 1 Hz, and at a heating rate of 10 ° C./min. The temperature at which the loss elastic modulus peaked was defined as Tg. (3) Thermal decomposition temperature 1 mg of the polyimide film was measured with a thermal analyzer (TG-DTA2000S type, manufactured by Mac Science) at a heating rate of 10 ° C./min in an air stream. The temperature at which the weight was reduced by 5% was defined as the pyrolysis temperature.

Reference Example 1 Preparation of dicyclohexyl-2,3,3 ', 4'-tetracarboxylic acid methyl ester Biphenyl-2,3 having a melting point of 75 ° C. was placed in a 1-liter autoclave equipped with a stirrer. , 3 ′, 4′-tetracarboxylic acid methyl ester (orthophthalic acid dimethyl ester is heated at normal pressure in the presence of oxygen with a catalyst of palladium acetate and 1,10-phenanthroline at normal pressure for 5 to 10 hours to form a coupling reaction. Biphenyl-
From a mixture containing an alkyl ester such as 2,3,3 ', 4'-tetracarboxylic acid methyl ester, the catalyst is reduced and filtered, the solvent is removed under reduced pressure, and distillation and crystallization by methyl alcohol are carried out. 77.1)
g (0.2 mol), 386 g of tetrahydrofuran, and 7.7 g of a catalyst in which 5% by weight of rhodium is supported on activated carbon (manufactured by N-Chemcat), and hydrogen pressure of 30
The hydrogenation reaction was performed at a reaction temperature of 100 ° C./kg/cm ² until a predetermined amount of hydrogen was absorbed. After the reaction, the catalyst was removed by filtration, and the solvent was removed by heating at 50 ° C. by evaporation to remove tetrahydrofuran as a solvent, and dicyclohexyl-2,3,3 ′, 4′-tetracarboxylic acid methyl ester as a white wax was obtained. 73.0 g (0.19 mol) were obtained. This white wax-like substance has an infrared absorption spectrum (JASCO FT / IR-5300 manufactured by JASCO Corporation).
Nuclear magnetic resonance spectrum: ¹ H-NMR (GSX manufactured by JEOL Ltd.)
As a result of analysis by -400 type nuclear magnetic resonance spectrometer), since the hydrogenation reaction was completed, it was confirmed to be dicyclohexyl-2,3,3 ', 4'-tetracarboxylic acid methyl ester. Was.

Reference Example 2 Production of dicyclohexyl-2,3,3 ', 4'-tetracarboxylic acid Dicyclohexyl-2,3,3', 4'- was added to a 1-liter autoclave equipped with a stirrer. 40 g (0.1 mol) of tetracarboxylic acid methyl ester and 800 g of water were charged, and the inside of the tank was inactivated with nitrogen. The mixture was heated to 200 ° C. and stirred for 8 hours to react. After completion of the reaction, excess water was removed from the reaction solution by evaporation, and the reaction solution was dried.
3.2 g (0.097 mol) of dicyclohexyl-2,3,3 ′, 4′-tetracarboxylic acid as white powdery crystals was obtained.

Reference Example 3 Production of dicyclohexyl-2,3,3 ', 4'-tetracarboxylic dianhydride Dicyclohexyl-2,3,3', 4'-tetracyclohexyl-2,3,3 ', 4'-tetracarboxylic acid Carboxylic acid 13.7
g (0.04 mol), pressure 1 mmHg, temperature 2
The dehydration reaction was performed at 00 ° C. for 10 hours. After cooling, 13.
0 g (0.038 mol) of dicyclohexyl-2,3,3 ′, 4′-tetracarboxylic dianhydride (melting point: 87.3-90.8 ° C.) as white powdery crystals was obtained.

Example 1 300 equipped with thermometer, stirrer and calcium chloride tube
34.6 g (0.08 mol) of 4,4′-bis (4-aminophenoxy) diphenylsulfone and 140 g of N-methyl-2-pyrrolidone as a reaction solvent were placed in a 3-ml three-necked flask, and the mixture was stirred at room temperature (25 ° C.). ) To dissolve with stirring.
In addition, dicyclohexyl-2,3, produced in Reference Example
27.4 g of 3 ', 4'-tetracarboxylic dianhydride
(0.08 mol) was added and stirring was continued at room temperature for 5 hours.
During this time, the viscosity of the polyamic acid reaction liquid increases with the elapse of the reaction time, and the viscosity when stirring for 5 hours is 40
Poise. The reaction solution was applied on a glass plate and dried. Next, after the temperature was increased stepwise from 80 ° C. to 240 ° C. and heat-treated, the film was peeled off from the glass plate,
A polyimide film having good thickness and good transparency was obtained. Next, the physical properties of this polyimide film were evaluated. The results are summarized in Table 1.

Example 2 16.0 g of 4,4'-diaminodiphenyl ether
(0.08 mol), dicyclohexyl-2,3,3 ′,
27.4 g of 4'-tetracarboxylic dianhydride (0.08
Mol) and 92 g of N-methyl-2-pyrrolidone were used in the same manner as in Example 1 to obtain a polyamic acid solution. Then, it was cast and dried in the same manner as in Example 1 and heat-treated at a maximum heating temperature of 250 ° C. for 1 hour to produce a polyimide film. The results are summarized in Table 1.

Comparative Example 1 11.9 g (0.11 mol) of para-phenylenediamine, 34.4 g (0.11 mol) of 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, N-methyl −
A polyamic acid solution was obtained in the same manner as in Example 1 except that 180 g of 2-pyrrolidone was used. Then, it was cast and dried in the same manner as in Example 1,
Heat treatment was performed for a time to produce a polyimide film. Table 1 shows the results of the evaluation.

Comparative Example 2 18.0 g of 4,4'-diaminodiphenyl ether
(0.09 mol), 26.5 g (0.11 mol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride,
A polyamic acid solution was obtained in the same manner as in Example 1 except that 180 g of N-methyl-2-pyrrolidone was used. Then
In the same manner as in Example 1, it was cast, dried and heat-treated at a maximum heating temperature of 400 ° C. for 1 hour to produce a polyimide film. Table 2 shows the results of the evaluation.

Comparative Example 3 3,4.6 g (0.08 mol) of 4,4'-bis (4-aminophenoxy) diphenyl sulfone, 2,3,3 ',
23.5 g of 4'-biphenyltetracarboxylic dianhydride
(0.08 mol), N-methyl-2-pyrrolidone 218
A polyamic acid solution was obtained in the same manner as in Example 1 except that g was used. Then, it was cast and dried in the same manner as in Example 1 and heat-treated at a maximum heating temperature of 350 ° C. for 1 hour to produce a polyimide film. Table 2 shows the results of the evaluation.

COMPARATIVE EXAMPLE 3 18.0 g of 4,4'-diaminodiphenyl ether
(0.09 mol), 2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride 26.5 g (0.09 mol),
A polyamic acid solution was obtained in the same manner as in Example 1 except that 120 g of N-methyl-2-pyrrolidone was used. Then
In the same manner as in Example 1, it was cast, dried and heat-treated at a maximum heating temperature of 350 ° C. for 1 hour to produce a polyimide film. Table 2 shows the results of the evaluation.

[0029]

[Table 1]

[0030]

[Table 2]

[0031]

According to the present invention, it is possible to obtain a polyimide precursor which is a novel polyamic acid or a polyamic acid ester which gives a polyimide having excellent heat resistance and transparency, and a novel polyimide.

Further, according to the present invention, it is possible to produce a polyimide precursor which is a novel polyamic acid or a polyamic acid ester which gives a polyimide having excellent heat resistance and transparency, and a novel polyimide.

Claims (4)

[Claims] 1. The following general formula [1], [2], [3] or [4] (Wherein, R ₁ represents a hydrogen atom or a monovalent hydrocarbon group, R ₂ represents a divalent hydrocarbon group, and m represents an integer.) A polyimide precursor which is a polyamic acid ester. 2. Dicyclohexyl-2,3,3 ′, 4 ′
A dicyclohexyl-2,3,3 ′, 4′-tetracarboxylic acid compound which is a tetracarboxylic acid, a diester or a dianhydride thereof, and a compound represented by the following general formula [5]: The polyamic acid or the polyamic acid ester according to claim 1, wherein the diamine is reacted with a diamine represented by the formula (wherein, R ₂ represents a divalent hydrocarbon group). Law. 3. The following general formula [6]: (Wherein, R ₂ represents a divalent hydrocarbon group, and m represents an integer.) A polyimide having a structural unit represented by the following formula: 4. A method for producing a polyimide, comprising subjecting the polyimide precursor according to claim 1 to a dehydration or dealcohol reaction to effect ring closure.