JPH0269526A - Polyimide resin and its manufacture - Google Patents

Abstract

PURPOSE: To provide the subject resin soluble in an organic solvent, excellent in heat resistance and useful for film by reacting a specified diamine with a tetracarboxylic dianhydride in an organic solvent.

CONSTITUTION: A diamine represented by the formula, H₂N-Ar-NH₂ (Ar is divalent tetraphenylfurane) [e.g. 3,4-bis(4-aminophenyl)-2,5-diphenylfurane or the like] is reacted with a tetracarboxylic dianhydride represented by the formula (R is tetravalent aromatic group) (e.g. pyromellitic dianhydride) in an organic solvent (e.g. cresol, nitrobenzene or the like), whereby the objective resin represented by formula II [(n) is 10-200] is provided.

COPYRIGHT: (C)1990,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a polyimide resin, particularly a novel polyimide resin that is soluble in various organic solvents and has a high glass transition temperature, and a method for producing the same.

(Prior Art) Conventionally, aromatic polyimide resins have excellent heat resistance as well as excellent electrical and mechanical properties, and have been widely used as industrial materials. However, many of these polyimide resins are insoluble in various organic solvents and mineral acids, and are also thermally infusible, making it extremely difficult to mold them.

(Problem to be solved by the invention) In the conventional aromatic polyimide resin as described above,
There are almost no aromatic polyimide resins that have a high glass transition temperature, excellent heat resistance, and good solubility in organic solvents, and that have both such heat resistance and processability. This has been a major problem in the commercial use of this resin. Therefore, an object of the present invention is to provide a novel polyimide resin that is soluble in various organic solvents and has a high glass transition temperature, and a method for producing the same.

(Means for Solving the Problems) The present inventors have worked diligently to produce a polyimide resin that is soluble in various organic solvents and mineral acids and has a high glass transition point, and have completed the present invention.

The first invention of the present invention is to react a diamine represented by the general formula with a tetracarboxylic dianhydride represented by the general formula (wherein R represents a tetravalent aromatic group) in an organic solvent. It is a polyimide resin represented by the formula - (wherein R is a tetravalent aromatic group, Ar is a divalent tetraphenylfuran group, and n is an integer from 1O to 200).

The second invention of the present invention has the following formula: This is a method for producing a polyimide resin represented by a furan group (n is an integer of 10 to 200).

The third invention of the present invention provides a diamine represented by the general formula % formula % () (in the formula, Ar represents a divalent tetraphenylfuran group) and a diamine represented by the general formula (in the formula, R represents a tetravalent aromatic By reacting a tetracarboxylic acid dithioanhydride represented by (representing a group) in an organic solvent, - maximum (wherein R is a tetravalent aromatic group, Ar is a divalent tetraphenylfuran group, n is an integer from 10 to 200).

Hereinafter, the structure of the present invention will be explained in further detail along with its operation.

The polyimide resin represented by the above-mentioned maximum N) and the diamine represented by the above-mentioned maximum N (II) and the above-mentioned diamine represented by the above-mentioned formula
), or a diamine represented by the above-mentioned maximum (II) and the above-mentioned maximum (T
It is produced from the tetracarboxylic acid dithioanhydride represented by V), but as the diamine, a diamine consisting of a divalent tetraphenylfuran group can be used alone, or one or more divalent diamines can be used. It is also possible to use a mixture of diamines consisting of an aromatic group.

The diamine consisting of a divalent tetraphenylfuran group represented by maximum (II) above refers to 3,4-bis(4-aminophenyl)-2,5-diphenylfuran.

This diamine is synthesized by converting paranitrobenzyl phenyl ketone into a diketone compound through an oxidative coupling reaction, converting this into a dinitrofuran compound through a dehydration cyclization reaction, and reducing the diketone compound.

Examples of the tetracarboxylic dianhydride derivatives represented by maximum (I[I) used in the present invention include pyromellitic dianhydride, 2.3.6.7-naphthalenetetracarboxylic dianhydride, 3.4.3'4'-Biphenyltetracarboxylic dianhydride, 2゜3,2',3'-biphenyltetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, 2 ,2-bis(
3,4-dicarboxyphenyl)propanihydride, bis(3,4-dicarboxyphenyl)ether dianhydride, bis(3,4-dicarboxyphenyl)sulfone dianhydride, 3゜4,3',4'- Examples include benzophenone tetracarboxylic dianhydride and 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride.

The tetracarboxylic acid dithioanhydride derivatives represented by the maximum (IV) used in the present invention include pyromellitic acid dithioanhydride, 2.3.6.7-naphthalenetetracarboxylic acid dithioanhydride, 3.4.3'4'-Biphenyltetracarboxylic acid thioni anhydride, 2, 3.2', 3
' -Biphenyltetracarboxylic acid dithioanhydride, bis(3,4-dicarboxyphenyl)methanethioanhydride, 2,2-bis(3,4-dicarboxyphenyl)propanethioanhydride, bis(3,4- dicarboxyphenyl)ether nitioanhydride, bis(3,4-dicarboxyphenyl)sulfonithioanhydride, 3.4.3',
Examples include 4'-benzophenonetetracarboxylic acid dithioanhydride and 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropanethioanhydride. These tetracarboxylic dithioanhydrides can be easily synthesized by reacting the corresponding tetracarboxylic dianhydride with sodium sulfide.

The method for producing the polyimide resin represented by the above-mentioned maximum (1) from the diamine represented by the above-mentioned maximum (If) and the tetracarboxylic dianhydride represented by the above-mentioned maximum (1) comprises substantially under anhydrous conditions, a diamine represented by -max (If) above and a diamine represented by -max (II) above;
The tetracarboxylic dianhydride derivative represented by I) is 0
After reacting at ~100°C for several tens of minutes to several days, 80~
This is carried out by reacting at 400''C for several tens of minutes to several days.

Here, the degree of polymerization n of the polyimide resin represented by -maximum (1) is the same as the diamine represented by -maximum (II), and -
It is limited by the charged amount of the tetracarboxylic dianhydride derivative represented by maximum (III), and when equimolar amounts of these reaction components are used, it is possible to produce a polyimide resin represented by maximum (1) above with a high degree of polymerization. Can be done. - The reason why the maximum (1) polyimide resin is limited to an integer between lθ and 200 is that when n is smaller than 10, the mechanical properties and heat resistance of the molded product, such as a film, are insufficient. This is because when n exceeds 200, solubility in organic solvents and moldability deteriorate.

Organic solvents that can be used in this method include amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone, sulfur solvents such as dimethyl sulfoxide and tetramethylene sulfone, and anisole. , diphenyl ether, nitrobenzene, benzonitrile, cresol, benzene solvents such as phenol, and the like. In particular, when using a solvent that can azeotrope with water, such as cresol or nitrobenzene, the latter stage of the reaction can be carried out at the boiling point of these solvents, and if the solvent is removed at the same time by distillation, even higher efficiency can be obtained. The reaction can proceed. Moreover, at this time, there is no problem even if the reaction is carried out by adding an additive such as isoquinoline.

In the present invention, the diamine represented by the above-mentioned maximum (n) is reacted with the tetracarboxylic dianhydride derivative represented by the above-mentioned maximum (III), group, Ar is a divalent tetraphenylfuran group, and n is an integer from 1O to 200).

Sroog, Macromolecular 5ynt
The polyimide resin of the present invention represented by -maximum (I) can also be produced by the method described in Heses CoCollactive Volume Volume 1, Page 295 (1977). The polyamic acid derivative represented by the above-mentioned maximum (V) is obtained by adding the diamine represented by the above-mentioned maximum (n) and the tetracarboxylic dianhydride derivative represented by the above-mentioned maximum (1) under substantially anhydrous conditions. It can be easily obtained by reaction.

The degree of polymerization of the polyamic acid derivative represented by the maximum (V) above is determined by the amount of the diamine represented by the maximum ([[)] and the tetracarboxylic dianhydride derivative represented by the maximum (n[) above. If these reaction components are used in equimolar amounts, it is possible to produce a polyamic acid derivative having a high degree of polymerization and having the above maximum (V).

The reaction temperature when producing the polyamic acid derivative represented by the above-mentioned maximum (V) can be selected between 0 and 300"C, but the reactants at high temperatures will have a polyimide structure that has undergone further reaction. It is preferable to control the reaction temperature to 60°C or less.Also, as an organic solvent that can be used for this reaction, it is possible to use a polyimide resin without going through the polyamic acid derivative represented by the general formula (V). The same organic solvents as those used in the above-mentioned case for the production of can be exemplified.

One of the methods for converting the polyamic acid derivative represented by the above-mentioned maximum (V) thus obtained into the polyimide resin represented by the above-mentioned maximum (1) is to convert the polyamic acid derivative represented by the above-mentioned maximum (V) into a polyimide resin represented by the above-mentioned maximum (1). This is a method of heating to a temperature of 150°C to 400°C.

This heating time varies depending on the heating temperature, but is generally between several minutes and several tens of hours. Alternatively, the polyamic acid derivative represented by the maximum (V) above can be easily converted into polyimide resin by chemical treatment such as treatment with an acid anhydride such as acetic acid, propionic acid, butyric acid, or benzoic acid. Cyclization can be achieved. Here, pyridine or the like can be used in combination as a substance that promotes the cyclization reaction.

Furthermore, as an alternative method for producing the polyimide resin represented by maximum (1) above, the reaction is allowed to proceed by the same method as the method for producing the polyamic acid derivative represented by formula (V) above, and then In the above period, additives such as acetic anhydride are added without isolating the polyamic acid derivative represented by formula (V) above, and further O'C ~ 300
The reaction is carried out for several minutes to several tens of hours at a temperature of 100°C.

The additives used in this reaction include the chemical treatment of the polyamic acid derivative represented by the formula (V).
Additives similar to those used in producing the polyimide resin represented by formula (1) can be used.

The method for producing the polyimide resin represented by the above formula (1) from the diamine represented by the above formula (II) and the tetracarboxylic acid dithioanhydride represented by the above formula (TV) comprises substantially above under anhydrous conditions -
Diamine represented by formula (n) and the above formula (IV)
The tetracarboxylic acid dithioanhydride derivative represented by 0
This is carried out by reacting at ~200°C for several tens of minutes to several days. Since this reaction involves the generation of hydrogen sulfide, the reaction can be considered to have ended when the generation of hydrogen sulfide is no longer observed. In this method, the degree of polymerization n of the polyimi F represented by the general formula (1) and the resin is determined by the diamine represented by the -C formula (II) and the tetracarboxylic acid dithioanhydride derivative represented by the formula (IV). It is limited by the amount of charge, and if equimolar amounts of these reaction components are used, a high degree of polymerization can be achieved by the above-mentioned formula (1).
) can be produced. - In the polyimide resin of formula ([), if n is smaller than 10, the mechanical properties and heat resistance of the molded product formed into a film etc. will be insufficient, and if n exceeds 200, the solubility in organic solvents etc. will be poor. or the moldability deteriorates.

Organic solvents that can be used in this method include amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, sulfur solvents such as dimethyl sulfoxide and tetramethylene sulfone, and anisole. , diphenyl ether, nitrohenzene, hendinitrile, cresol, benzene solvents such as phenol, and the like.

The organic solvent may be used in an amount sufficient to dissolve one of the reaction components. Usually, polyimide with a high degree of polymerization can be obtained by using the reaction component in an amount of 0.05 to 50%.

The polymerization reaction may proceed in a solution state, or the polymer may precipitate from the reaction system. Molded articles such as polyimide resin films can be directly formed from this polymerization solution.

The thus produced polyimide resin represented by the general formula (1) is determined by the manufacturing method used, the type and amount of other diamines that can be used in combination with the diamine represented by the formula (■), and the general formula (III) used. Although the solubility varies depending on the type of the tetracarboxylic dianhydride derivative represented by the formula (IV) and the tetracarboxylic dithioanhydride derivative represented by the formula (IV), in many polyimide resins, mineral acids such as sulfuric acid are used. becomes soluble in In some resins, N, N-dimethylformamide, N, N
dimethylacetamide, N-methyl-2-pyrrolidone,
It becomes soluble in all or part of solvents such as dimethylimidazolidinone, dimethyl sulfoxide, and cresol.

Most of the polyimide resins represented by the above formula (1) have a high glass transition point of 300°C or higher, are thermally stable, and do not undergo thermal decomposition even when heated to around 500°C.

(Example) Hereinafter, the present invention will be explained in more detail with reference to Examples.

1L0=3.4-bis(4-aminophenyl)-2,5-diphenylfuran 0.403 g (1 mmol) and 0.4
g of isoquinoline was dissolved in 5 mL of purified metacresol and heated to 40° C. under nitrogen flow. To this solution was added 0.322 g (1 mmol) of 3.4.3',
4'-benzophenonetetracarboxylic dianhydride was added. This solution was reacted at 45°C for 3 hours and at 150°C for 3 hours with stirring. A distillation device was attached to the reaction apparatus, and the solvent metacresol was distilled under a nitrogen stream at an oil bath temperature of 240°C. At this time, metacresol containing 0.5% isoquinoline was added so as to maintain the liquid volume in the reactor at about 4 mL. After performing this operation for 5 hours, the mixture was cooled to room temperature under a nitrogen stream to obtain a yellow polyimide resin solution. A portion of this solution was poured into 300 mL of methanol to obtain a polyimide resin precipitate, which was filtered and dried under vacuum at 100"C.The remaining polymerization solution was cast onto a glass plate.
This was vacuum dried at 100°C and then at 180°C to obtain a polyimide film.

Intrinsic viscosity: 0.45 dL/g (measured in N-methylpyrrolidone at a concentration of 0.5 g/dL at 30°C) Infrared absorption spectrum (film): 1770.1?1
0゜1355, 720 cm-' (Both are characteristic absorptions of imide bonds) Elemental analysis values Carbon Hydrogen Nitrogen Calculated values (%) 78.48 3.51 4.0
7 Actual value (%) 77.63 3.32 3.
80 Glass transition temperature = 340°C 10% weight loss 485°C in air, 56°C in nitrogen
It was 0°C.

Solubility: Soluble in sulfuric acid, metacresol, orthochlorophenol, pyridine, dimethylimidazolidinone, N-methylpyrrolidone, etc.

1 ± 1 0.805 g (2 mmol) of 3.4-bis(4-aminophenyl-2,5-diphenylfuran) was dissolved in 3 mL of purified N-methylpyrrolidone.
, 436 g (2 mmol) of pyromellitic anhydride was added under a nitrogen stream and heated at 12-15 °C for 1 hour at 20-25 °C.
The reaction was carried out at C for 5 hours. A portion of the obtained polymerization solution was
The polyamic acid was poured into 0 mL of methanol to precipitate it, and after filtration, it was vacuum dried at room temperature (intrinsic viscosity: 0.40 dL/
g, in dimethylacetamide, concentration 0.5 g/d
On the other hand, the remaining polymerization solution was cast on a glass plate and dried at 80°C to obtain a polyamic acid film.The film was heated at 100°C at 120°C.
A polyimide film was obtained by heat treatment at 0°C and 300°C for 1 hour each.

Infrared absorption spectrum (film) 71775.1?1
5゜1355, 720 ell-' (both characteristic absorption of imide bond) Intrinsic viscosity: 0.35 dL/g (
Measured in sulfuric acid at a concentration of 0.5 g/dL at 30°C) Elemental analysis carbon hydrogen nitrogen calculated value (%) 78.08 3.45 4.7
9 Actual value (%) 77.31 3,20 4.
54 Glass transition temperature = 396°C 1O% weight loss temperature: 550°C in air, 57°C in nitrogen
It was 0”C.

Solubility: Soluble only in sulfuric acid.

By the same operation as in Example 2, 3,4-bis(4-aminophenyl)-2,5-diphenylfuran 0.805
g (2 mmol) and 3.4.3', 4'-benzophenonetetracarboxylic dianhydride 0.645 g (
2 mmol) to polyamic acid (intrinsic viscosity 0.46 dL)
/ g, in dimethylacetamide, concentration 0.5 g/dL
, measured at 30°C), and heat-treated it to obtain a polyimide resin.

Infrared absorption spectrum: 17?0.1710.1355
．． 720ell-' (all characteristic absorption of imide bond)
Intrinsic viscosity: 0.35 dL/g, (in sulfuric acid, concentration 0.
5 g/dL, measured at 30°C) Glass transition temperature: 8344°C 1O% weight loss temperature: 490°C in air, 57°C in nitrogen
It was 0°C.

Solubility: Soluble only in sulfuric acid.

1 boat■ soil 3.4-bis(4-aminophenyl)-2,5-diphenylfuran 0.805 g (2n+mol) 10
Dissolved in mL of N-methylpyrrolidone. In addition to this, 3.
4. Add 0.709 g (2sv+ol) of 3'4'-benzophenonetetracarboxylic acid dithioanhydride,
The reaction was carried out at 0° C. for 10 hours under a nitrogen stream. A part of the polymerization solution was cast onto a glass plate and heated at 100°C and then 180"
A polyimide film was obtained by vacuum drying at C. The remaining polymerization solution was poured into 300 mL of methanol,
Polyimide was precipitated, filtered, and dried under reduced pressure at 100''C to obtain polyimide.

Infrared absorption spectrum: 1775.1?15.1360
．． 720C111-1 (both characteristic absorption of imide bond) Intrinsic viscosity: 0.49 dL/g (measured in N-methylpyrrolidone at a concentration of 0.5 g/dL at 30″C)
Elemental analysis carbon hydrogen nitrogen calculated value (%) 78.48 3.51 4.0
7 Actual value (%)? 7.69 3.23 3.96 Glass transition temperature: 340°C 10% weight loss 490°C in air and 5 in nitrogen
The temperature was 65°C.

Solubility: Soluble in sulfuric acid, metacresol, orthochlorophenol, pyridine, dimethylimidazolidinone, N-methylpyrrolidone, etc.

(Effects of the Invention) The present invention provides a polyimide resin represented by formula (I) and an advantageous method for producing the polyimide resin. Most conventional polyimide resins have low solubility in organic solvents and are therefore difficult to mold, whereas the polyimide resin of the present invention is soluble in organic solvents, and the production method of the present invention It has the characteristic that it can be obtained as an organic solvent solution by a method, and molded products such as polyimide resin films can be easily molded from this solution.Moreover, it has excellent heat resistance, so it has great value as an industrial material.

Claims (1)

[Claims] 1. General formula▲ Numerical formula, chemical formula, table, etc.▼ (In the formula, R is a tetravalent aromatic group, Ar is a divalent tetraphenylfuran group, and n is an integer from 10 to 200. Polyimide resin represented by 2. Diamine represented by the general formula H_2N-Ar-NH_2 (in the formula, Ar represents a divalent tetraphenylfuran group) and the general formula ▲ There are numerical formulas, chemical formulas, tables, etc. ▼ (in the formula, R represents a tetravalent tetraphenylfuran group) There are general formulas ▲ mathematical formulas, chemical formulas, tables, etc. that are characterized by reacting tetracarboxylic dianhydride represented by (representing an aromatic group) in an organic solvent. group group, Ar is a divalent tetraphenylfuran group, and n is an integer of 10 to 200). 3. Diamine represented by the general formula H_2N-Ar-NH_2 (in the formula, Ar represents a divalent tetraphenylfuran group), and the general formula ▲ There are numerical formulas, chemical formulas, tables, etc. ▼ (in the formula, R is tetraphenylfuran) The general formula is characterized by reacting tetracarboxylic acid dithioanhydride (representing a valent aromatic group) in an organic solvent. Ar is a divalent tetraphenylfuran group, and n is an integer of 10 to 200.