JPH07133349A - Copolyimide and its production - Google Patents

Abstract

PURPOSE:To advantageously industrially a copolyimide which is excellent in various characteristics such as heat resistance and has high mechanical strengths, a low coefficient of linear, thermal expansion, and an excellent thermal dimensional stability. CONSTITUTION:A copolyimide mainly comprising repeating units of formulas I and II (R<1> is a tetravalent arom. hydrocarbon group) is produced by copolymerizing an arom. diamine component mainly comprising a 4,4'- diaminodiphenyl ester and 4,4'-diaminodiphenyl ether with a tetracarboxylic dianhydride and subjecting the resulting polyamic acid copolymer to cyclization by dehydration thermally or chemically.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention is excellent in various properties such as heat resistance, has high mechanical strength and a low coefficient of thermal expansion, and is suitable as a base material for fine patterned flexible printed wiring boards and the like. The present invention relates to a polyimide copolymer and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
Polyimide resin is known to have various properties such as excellent heat resistance, chemical resistance, electrical properties, and mechanical properties. As a polyimide resin, Japanese Patent Publication No. 36-10
Those obtained from 4,4′-diaminodiphenyl ether and pyromellitic dianhydride described in Japanese Patent Publication No. 999 are well known. However, since this polyimide resin contains a flexible ether bond in the main chain, it is highly flexible even though it is a wholly aromatic polyimide, but it has a low coefficient of elasticity and a large linear expansion coefficient and poor thermal dimensional stability. There was a problem. In particular, the polyimide resin that has been widely used in the past has a large linear expansion coefficient of about 3 × 10 ⁻⁵ / ° C., has poor thermal dimensional stability, and is liable to warp or curl when laminated with a metal or the like. It was

On the other hand, in recent years, there has been an increasing demand for polyimide resins having more excellent thermal dimensional stability and mechanical strength. Therefore, various studies have been conducted for improving the properties of polyimide resins, and in particular, many efforts are made to improve mechanical strength, thermal dimensional stability, etc. by using two or more kinds of aromatic diamines. However, in any of these approaches, the thermal dimensional stability and mechanical properties of the polyimide resin could not be satisfied at the same time.

The present invention has been made in view of the above circumstances.
It has excellent properties such as heat resistance and high mechanical strength.
Another object of the present invention is to provide a polyimide copolymer having excellent thermal dimensional stability and an industrially advantageous method for producing the polyimide copolymer.

[0005]

Means and Actions for Solving the Problems The present inventor has conducted extensive studies to achieve the above object, and as a result, 4,4′-
The following general formula obtained by dehydrating and ring-closing a polyamic acid copolymer obtained by polymerizing an aromatic diamine containing diaminodiphenyl ester and 4,4′-diaminodiphenyl ether as main components and tetracarboxylic dianhydride The polyimide copolymer containing the repeating unit represented by (1) and the repeating unit represented by the following general formula (2) as a main constituent unit at a molar ratio of preferably 5/95 to 85/15 is heat resistant. In addition to being excellent in various properties, such as high mechanical strength, low thermal expansion coefficient and water absorption rate, high elastic modulus and flexibility, it has excellent thermal dimensional stability. Invented.

[0006]

[Chemical 2] (However, in the formula, R ¹ is a tetravalent aromatic hydrocarbon group.)

Therefore, the present invention comprises a polyimide copolymer characterized by containing a repeating unit represented by the general formula (1) and a repeating unit represented by the general formula (2) as main constituent units, and An aromatic diamine containing 4,4'-diaminodiphenyl ester and 4,4'-diaminodiphenyl ether as main components is polymerized with a tetracarboxylic acid dianhydride to obtain a polyamic acid copolymer, and then the polyamic acid copolymer is obtained. There is provided a method for producing the above polyimide copolymer, which comprises subjecting the polymer to dehydration ring closure.

The present invention will be described in more detail below. The polyimide resin of the present invention has a repeating unit represented by the following general formula (1) and a repeating unit represented by the following general formula (2) as main constituent units. It includes.

[0009]

[Chemical 3]

R ¹ in the above formula is a tetravalent aromatic hydrocarbon group, which is derived from the main skeleton of the tetracarboxylic dianhydride. Specifically, as tetracarboxylic dianhydride, pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3,3 ′,
4'-biphenyltetracarboxylic dianhydride, 3,3 '
4,4'-benzophenone tetracarboxylic dianhydride,
2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl)
Propane dianhydride, bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane Dianhydride, 3,4,9,10
-Berylene tetracarboxylic dianhydride, benzene-1,
2,3,4-tetracarboxylic dianhydride, 2,3,6
7-anthracene tetracarboxylic dianhydride, 1,2,
7,8-Phenylenelentetracarboxylic dianhydride and the like can be mentioned, and one of these can be used alone or two or more can be used in combination.

Here, the repeating unit of the above formula (1) and the repeating unit of the above formula (2) are contained in the polyimide copolymer in a molar ratio of 5/95 to 85/15, particularly 20/80 to 70 /. Thirty
It is preferable to exist in the ratio of. If the molar ratio of the repeating unit of the formula (1) exceeds 85%, the flexibility of the polyimide copolymer may be extremely lowered, and if the molar ratio of the repeating unit of the formula (2) exceeds 95%, the polyimide copolymer In some cases, the effects of improving the linear expansion coefficient, water absorption coefficient and elastic modulus of the polymer may not be sufficiently obtained.

The above-mentioned polyimide copolymer is a high molecular weight polymer and has a viscosity of 0.5 as a polyamic acid.
Measured temperature 30 when measured in g / 100 ml DMF
The logarithmic viscosity at 0 ° C. is preferably 0.5 to 5.

The above-mentioned polyimide copolymer of the present invention has 4,
An aromatic diamine containing 4'-diaminodiphenyl ester and 4,4'-diaminodiphenyl ether as main components is polymerized with the tetracarboxylic acid dianhydride to obtain a polyamic acid copolymer, and then the polyamic acid copolymer is prepared. It can be produced by subjecting the polymer to dehydration ring closure.

Here, the mixing ratio of 4,4'-diamino ester of aromatic diamine and 4,4'-diaminodiphenyl ether is 5/95 to 85/15, especially 20/80 to 70/30 in terms of molar ratio. It is preferable that

In the present invention, the aromatic diamine is 4,
Although it is most preferable to use only 4'-diamino ester and 4,4'-diaminodiphenyl ether, other aromatic polyvalent amine compounds can be used in combination with these aromatic diamines.

Specific examples of the aromatic diamine compound that can be used in combination include 4,4'-bis (4-aminophenoxy) biphenyl, 4,4'-diaminodiphenyl sulfone,
3,3′-diaminodiphenyl sulfone, bis [4-
(4-Aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (2-aminophenoxy) phenyl] sulfone, 1,4-bis (4-aminophenoxy) benzene , 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene,
1,4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] ether,
4,4'-diaminodiphenylmethane, bis (3-methyl-4-aminophenyl) methane, bis (3-chloro-
4-aminophenyl) methane, 3,3′-dimethoxy-
4,4'-diaminobiphenyl, 3,3'-dimethyl-
4,4'-diaminobiphenyl, 3,3'-dichloro-
4,4'-diaminobiphenyl, 2,2 ', 5,5'-
Tetrachloro-4,4'-diaminobiphenyl, 3,
3'-dicarboxy-4,4'-diaminobiphenyl,
3,3′-dihydroxy-4,4′-diaminobiphenyl, 4,4′-diaminodiphenyl sulfide, 3,
3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4'-diaminobiphenyl, 4,4'-diaminooctafluorobiphenyl, 2,4-diaminotoluene, paraphenylenediamine , Metaphenylenediamine, 4,4'-diaminobenzanilide, 3,4'-
Diaminobenzanilide, 4,3'-diaminobenzanilide, 2,2-bis [4- (4-aminophenoxy)
Phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,
2-bis (3-hydroxy-4-aminophenyl) propane, 2,2-bis (3-hydroxy-4-aminophenyl) hexafluoropropane, 9,9-bis (4-aminophenyl) 10-hydro-anthracene , Orthotrizine sulfone and the like. In addition to the above diamine compounds, some tetraamines such as 3,3′4,4′-biphenyltetraamine and 3,3′4,4′-tetraaminodiphenyl ether can also be used.

Aromatic polyvalent amine compounds other than 4,4'-diaminodiphenyl ester and 4,4'-diaminodiphenyl ether can be used within a range that does not impair the objects and effects of the present invention. The amount is preferably not more than 10 mol%, particularly not more than 5 mol%.

In the polymerization reaction of the aromatic diamine and the tetracarboxylic dianhydride, the two compounds are mixed in an organic polar solvent at a molar ratio of 100 to 100 parts of the aromatic diamine and 95 to 105 of the tetracarboxylic dianhydride. It is particularly desirable to mix them in equimolar proportions.

Further, as the organic polar solvent, for example, sulfoxide-based solvent such as dimethyl sulfoxide, N, N
-Formamide solvents such as dimethylformamide, N, N-diethylformamide, acetamide solvents such as N, N-dimethylacetamide, N, N-diethylacetamide, N-methyl-2-pyrrolidone, N-vinyl-2
-Pyrrolidone-based solvents such as pyrrolidone, phenol, o
Examples of the solvent include phenol solvents such as-, m- or p-cresol, xylenol, halogenated phenol, and catechol, hexamethylphosphorum amide, and γ-butyrolactone. These organic polar solvents are 1
The types may be used alone or in combination of two types,
Further, an aromatic hydrocarbon-based organic nonpolar solvent such as xylene or toluene can be used in combination. The amount of the above organic polar solvent used is not particularly limited, but the polyamic acid copolymer obtained by the polymerization reaction is 5 to 3 in the organic polar solvent.
It is desirable to determine the amounts of aromatic diamine, tetracarboxylic dianhydride, and organic polar solvent used so that 0% by weight, particularly 10 to 20% by weight, is dissolved.

The above polymerization reaction conditions are 0 to 70 ° C., especially 0
It is preferable to carry out at a temperature of -30 ° C for 1 to 50 hours, particularly 3 to 20 hours, and a polyamic acid copolymer can be efficiently obtained by this polymerization reaction.

The dehydration ring closure of the above polyamic acid copolymer can be carried out by a usual method, and thermal or chemical dehydration ring closure can be preferably adopted. Here, as the thermal dehydration ring-closing method, a method of heating at 200 to 500 ° C. for 5 to 120 minutes is preferable.

A method using a dehydrating agent and a catalyst is suitable for chemically dehydrating and ring-closing the polyamic acid copolymer. In this case, as the dehydrating agent, for example, aliphatic acid anhydride, aromatic acid anhydride, N, N′-dialkylcarbonimide, lower fatty acid halide, halogenated lower fatty acid halide, halogenated lower fatty acid anhydride, allyl Examples thereof include phosphonic acid dihalides and thionyl halides, which may be used alone or in combination of two or more. The amount of the dehydrating agent used is preferably about 0.5 to 10 mols, and particularly preferably 2 to 6 mols per repeating unit of the polyamic acid.

Examples of the catalyst include aliphatic tertiary amines such as triethylamine, aromatic tertiary amines such as dimethylaniline, and heterocyclic tertiary amines such as pyridine, β-picoline and isoquinoline. These can be used alone or in combination of two or more. The amount of the catalyst used is about 0. per repeating unit of polyamic acid.
An amount of 01 to 4 molar amount, particularly 0.1 to 2 molar amount is preferable.

The reaction conditions for the above chemical dehydration ring closure are as follows:
0.2 to 20 hours at 70 to 400 ° C, especially 100 to 30
Preference is given to 0 ° C. for 1 to 5 hours.

In order to obtain a polyimide copolymer in the form of a film, an organic polar solvent solution of the above polyamic acid copolymer is cast or applied on a support such as an endless belt to form a film, and this film is 100-150. Dry at 10 ° C and add 10-
A self-supporting membrane of polyamic acid containing 30% is obtained.
Next, after peeling off this film from the support and fixing the end portion, the film is heated to about 200 to 250 ° C. to eliminate the solvent, and dehydrated and imidized at 300 to 500 ° C. to have a thickness of 10 to 150 μm. A polyimide film can be obtained.

[0026]

INDUSTRIAL APPLICABILITY The polyimide copolymer of the present invention has excellent properties such as heat resistance, high mechanical strength, low linear expansion coefficient, and excellent thermal dimensional stability. Therefore, it is suitable as a film material such as an electrically insulating material or a fine patterned flexible wiring board. Further, according to the production method of the present invention, the polyimide copolymer can be industrially advantageously produced.

[0027]

EXAMPLES The present invention will be specifically described below with reference to Reference Examples, Examples and Comparative Examples, but the present invention is not limited to the following Examples.

Reference Example 4,4′-diaminodiphenyl ester was synthesized by the following method. Tetrahydrofuran 5
00 ml and p-nitrophenol 43.8 g (0.25
mol) and 28.3 g (0.28 mo) of triethylamine
l) was dissolved and cooled to 0 ° C., and then, 46.4 g of p-nitrobenzoyl chloride was added to 100 ml of tetrahydrofuran.
The temperature of the reaction solution is 1 when the solution of (0.25 mol) is dissolved.
It was added dropwise so as to be 0 ° C. or lower. Then return to room temperature,
Stirring was continued for 2 hours.

Next, the precipitate was filtered, washed with tetrahydrofuran, further washed with water and methanol, and then dried to obtain white crystals of 4,4'-dinitrodiphenyl ester. The yield was 68.9 g (yield 95.6%). The crude crystal was treated with N, N'-dimethylformamide (D
It was recrystallized from MF) / methanol to obtain a pure product.

52.0 of 4,4'-dinitrodiphenyl ester obtained above in 1000 ml autoclave
g (0.18 mol) was added together with 3 g of 5% Pd / C and 600 ml of dimethylformamide. Hydrogen was introduced with vigorous stirring at 60 ° C., and stirring was continued until hydrogen absorption was no longer observed. After cooling, it is filtered and the catalyst (Pd
/ C) was removed, the mixture was further concentrated under reduced pressure, poured into 1000 ml of water, and the precipitate was filtered. After washing with water and methanol,
After drying under reduced pressure, white crystals of 4,4'-diaminodiphenyl ester were obtained. Yield 40.9g (Yield 99.6%)
Met. The crude crystal was recrystallized with a mixed solvent of dimethylformamide / methanol to obtain a pure product.

Comparative Example 1 DM was added to a 500 ml flask.
Put F188.3g, 4,4 'while flowing nitrogen gas
-Diaminodiphenyl ether 10.102 g (0.0
50 mol) was added and dissolved in DMF. Pyromellitic dianhydride 10.906g (0.050mo
1) was added and reacted at 25 ° C. for 3 hours.

Next, these amic acid solutions were thinly spread on a glass plate with an applicator, dried in an oven at 110 ° C. for 60 minutes, peeled off, fixed on an iron frame, and fixed at 200 ° C.
When desolvation was carried out for 60 minutes at 300 ° C. for 60 minutes, a film having a thickness of about 25 μm was obtained. When the characteristics of the film were measured by the following methods, the results shown in Table 1 were obtained. Mechanical Properties (Tensile Strength, Elastic Modulus, Elongation ) Measured based on ASTM D882-88. Linear expansion coefficient Using a thermal analyzer TMA-7000 manufactured by Vacuum Riko Co., Ltd., an average value of linear expansion coefficients at 150 to 200 ° C was obtained at a temperature rising rate of 5 ° C / minute. Water absorption The polyimide film was left at 90% RH for 24 hours, and the weight before and after that was measured to determine the water absorption. The logarithmic viscosity polyamic acid concentration was 0.5 g / 100 ml DMF, and the measurement temperature was 30 ° C.

[0033]

[Equation 1]

Comparative Example 2 DM was added to a 500 ml flask.
Put F224.0g, 4,4 'while flowing nitrogen gas
-Diaminodiphenyl ester 11.413 g (0.0
50 mol) was added and dissolved in DMF. Then, a film was obtained in the same manner as in Comparative Example 1. The characteristics of the film are as shown in Table 1 and were found to be extremely brittle.

Comparative Example 3 DM was added to a 500 ml flask.
Put F222.5g, while flowing nitrogen gas 4,4 '
-Diaminodiphenyl ether 10.102 g (0.0
50 mol) was added and dissolved in DMF. Then 3,
3'4,4'-biphenyltetracarboxylic acid 14.71
After adding 1 g (0.050 mol) and reacting at 25 ° C. for 3 hours, a film was obtained in the same manner as in Comparative Example 1. The characteristics of the film were as shown in Table 1.

Comparative Example 4 DM was added to a 500 ml flask.
Put F235.1g, while flowing nitrogen gas, 4, 4 '
-Diaminodiphenyl ester 11.413 g (0.0
50 mol) was added and dissolved in DMF. Then 3,
3'4,4'-biphenyltetracarboxylic acid 14.71
After adding 1 g (0.050 mol) and reacting at 25 ° C. for 3 hours, a film was obtained in the same manner as in Comparative Example 1. The characteristics of the film are as shown in Table 1 and were found to be extremely brittle.

[Examples 1 to 3] Both 4,4'-diaminodiphenyl ester and 4,4'-diaminodiphenyl ether were used as the aromatic diamine, and both compounds were used.
A film was obtained in the same manner as in Comparative Example 1 using pyromellitic dianhydride as shown in Table 1. The film properties are shown in Table 1.

Example 4 As aromatic diamine 4,
A film was obtained in the same manner as in Comparative Example 3 using 4′-diaminodiphenyl ester and 4,4′-diaminodiphenyl ether in a molar ratio of 1: 1. The film properties are shown in Table 1.

From the results shown in Table 1, it was confirmed that the polyimide copolymer of the present invention has excellent mechanical strength, low linear expansion coefficient and water absorption, high elastic modulus and flexibility.

[0040]

[Table 1]

[Procedure amendment]

[Submission date] January 10, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction content]

[0040]

[Table 1]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masahiro Yuyama, Inventor Masahiro Yuyama 1 Towada, Kamisu-cho, Kashima-gun, Ibaraki Shin-Etsu Chemical Co., Ltd., Polymer Functional Materials Research Center (72) Inventor Kiyoshi Motoumi Kashima-gun, Ibaraki Prefecture No. 1 Towada, Kamisu Town, Shin-Etsu Chemical Co., Ltd.

Claims (3)

[Claims] 1. A polyimide copolymer comprising a repeating unit represented by the following general formula (1) and a repeating unit represented by the following general formula (2) as main constituent units. [Chemical 1] (However, in the formula, R ¹ is a tetravalent aromatic hydrocarbon group.) 2. The polyimide according to claim 1, wherein the molar ratio of the repeating unit represented by the general formula (1) to the repeating unit represented by the general formula (2) is 5/95 to 85/15. Copolymer. 3. A polyamic acid copolymer is obtained by polymerizing an aromatic diamine containing 4,4′-diaminodiphenyl ester and 4,4′-diaminodiphenyl ether as main components and tetracarboxylic dianhydride, The polyimide copolymer according to claim 1, wherein the polyamic acid copolymer is subjected to dehydration ring closure.