JPH0196219A - Aromatic polyimide copolymer - Google Patents

Abstract

PURPOSE:To provide the titled copolymer free from deterioration when subjected to molding, outstanding in heat and solvent resistances and mechanical properties, useful for electrical or electronic parts, etc., produced from a specific aromatic tetracarboxylic dianhydride component and ether-based aromatic diamine component, etc. CONSTITUTION:A polymerization is carried out on heating between (A) an aromatic tetracarboxylic dianhydride of formula I (Ar2 is tetravalent aromatic residue) (e.g. 3,3'4,4'-biphenyltetracarboxylic dianhydride), (B) an ether-based aromatic diamine of formula II [X is O or C(CH3)2; Ar1 is divalent aromatic residue] [e.g., 4,4'-bis(4-aminophenoxy)diphenylsulfone], and (C) a thioether-based aromatic diamine of formula III (Ar3 is divalent aromatic residue) [e.g. 4,4'-bis(4- aminophenylthio)diphenylsulfide] to obtain the objective copolymer constituted of (1) 51-99mol.% of recurring units of formula IV and (2) 49-1mol. of other recurring units of formula V.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a novel polyimide copolymer.

The aromatic polyimide copolymer produced by the present invention is
It is useful for super engineering plastics, heat-resistant fibers, heat-resistant films, heat-resistant coating materials, etc.

[Conventional technology]

It is known that an aromatic polyimide with excellent heat resistance can be obtained by the reaction of an aromatic tetracarboxylic dianhydride with an aromatic diamine (C1E 5ROOG, "Journal of Polymer Science", Macromolecules). Review, Vol. 11, p. 161, 1976). However, the aromatic polyimides that have been proposed for boat fishing have been difficult to melt and mold, and their uses have been limited.

In order to improve this drawback, an aromatic polyimide using an aryloxy dianhydride as the 11-acid anhydride was studied (Japanese Patent Publication Nos. 57-20966 and 57-2).
No. 0967, etc.), Polyetherimide Ultem”
(General Electric Company's product name). This type of aromatic polyimide has excellent melt moldability (injection molding, extrusion molding).

On the other hand, (2) aromatic polyimide obtained by the reaction of an aromatic diamine having a (thio)ether bond with pyromellitic dianhydride (JP-A-59-170122, JP-A-61-250031, etc.) , polyimide sulfone resin (U.S. Patent No. 4.398.021, etc.), etc.
Examples have also been reported in which melt molding is possible without significantly reducing heat resistance.

[Problem that the invention seeks to solve]

However, the material (1) described above, on the other hand, has lower heat resistance and solvent resistance than conventional aromatic polyimides.

Furthermore, the method (2) is still insufficiently practical in the engineering and electronics fields, which require a balance between heat resistance and mechanical properties. In many cases, bending C such as 10-, 13O□-, and -0- is introduced into Hi to ensure formability.
H.

Due to the effects of the sexual linking groups and meta-bonds, there were problems such as a decrease in environmental resistance and thermal deterioration during molding.

[Means for solving problems]

The present inventors have discovered that in aromatic polyimides that use ether-based aromatic diamines as the main component, by combining them with aromatic diamines having a thioether bond, superior properties can be achieved compared to when ether-based aromatic diamines are used alone. It was confirmed that the moldability could be improved while maintaining the physical properties, and the present invention was completed.

That is, the present invention provides the following novel polyimide copolymer.

(1) Aromatic polyimide H3 (in the formula, -X - represents -o-, -c-, -Ar,
-H3 and -Arz- are divalent aromatic residues, :;ArZ<
is a tetravalent aromatic residue. ) In particular, (2) the divalent aromatic residue is (A is O, Co, 50. SOz, CyHzy).

However, y is an integer from 1 to 10. Y is an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, and 3 carbon atoms.
-20 cycloalkyl group, C6-20 aryl group, halogen group, and nitro group. a, b, c, d,
e and f represent integers of 0 to 4. An aromatic polyimide copolymer (X represents a number of 0 to 20), and (3
) A tetravalent aromatic residue, (B+-, -82- is -o-, -s-, -co-.

-5O2+, -NHC-. Further, a and a' are O or 1. -Ara- is a divalent aromatic residue. ) aromatic polyimide copolymer.

The aromatic polyimide copolymer of the present invention has improved moldability while maintaining excellent physical properties compared to existing aromatic polyimide (co)polymers.

The aromatic polyimide copolymer of the present invention has the following formula (I[I)
51 to 99 mol% of ether aromatic diamine represented by
and 49 to 1 mol % of an aromatic diamine having a thioether bond represented by the following formula (IV) are reacted with an aromatic polycarboxylic dianhydride represented by the following formula (V).

[In the formula, X, Ar+, ^rZ+ Ar3 are the above formula (I
).

Same as (If)] The following two methods are preferable.

However, it is not limited to this.

(1) - Step method A method for obtaining polyimide by heating an aromatic diamine and a carboxylic dianhydride in a solution or molten state, and polymerizing the resulting water while removing it from the system.

(2) Two-step method An aromatic diamine and a carboxylic dianhydride are reacted in a solution state to obtain a polyamic acid (first step).

The polyamic acid is dehydrated and ring-closed in a solution state or a solid phase state to obtain a polyimide (second step).

A two-step method.

Let me explain these two methods in more detail.
- and as follows.

(1) - A method for producing an aromatic polyimide copolymer by a stepwise method.

Ether aromatic diamine represented by formula (III) 0.
51 to 0.99 mol, 0.49 to 0.01 mol of thioether aromatic diamine represented by formula (IV), and formula (V
) Aromatic polycarboxylic dianhydride 0.90~
1.10 mol (preferably 0.95-1.05 mol)
and dissolved or dispersed in an organic solvent, and
The polymer is obtained by heating to 0°C, preferably 150 to 250°C (solution method).

At this time, it is effective to use an azeotropic solvent useful for removing water, such as benzene, toluene, xylene, and chlorobenzene.

Moreover, it may be preferable to simultaneously add an organic acid such as p-)luenesulfonic acid or benzenesulfonic acid as a catalyst.

Organic solvents used in this method (solution method) include halogenated aromatic hydrocarbons, such as dichlorobenzene, trichlorobenzene, chlornaphthalene, etc.; phenolic compounds, such as phenol, cresol, chlorophenol, xylenol, etc.; aliphatic Carboxylic acids, such as acetic acid, propionic acid, etc.: aprotic polar solvents, such as N,
N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethylpropionamide, N,N-dimethylbenzamide, N-methylpyrrolidone, N-methylpiperidone, N-methyl-ε-caprolactam, hexamethylphosphoramide, Tetramethylurea, 1.3-
Dimethyl-2-imidazolidinone, sulfolane, dimethyl sulfoxide, etc.; aliphatic glycol ethers, such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, etc.; and mixtures thereof. Among these, dichlorobenzene, trichlorobenzene, cresol, chlorophenol, N,N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, diethylene glycol dimethyl ether and the like are particularly preferred.

In addition, as a -step method, 0.51 to 0.99 mol of ether aromatic diamine represented by formula (III) and formula (I
V) Thioether aromatic diamine 0.49~
0.01 mol and 0.90 to 1.10 mol (preferably 0.01 mol) of the aromatic polycarboxylic dianhydride represented by formula (V).
．． 95 to 1.05 mol) and heated to 150 to 400°C.
A method of obtaining the polymer by heating it in a molten state (preferably 250 to 350°C) (melt method) may be adopted.

At this time, polymerization is accelerated by forcibly removing generated water from the system.

(2) A method for producing an aromatic polyimide copolymer by a two-step method.

i) Polyamic acid manufacturing process (first step).

Ether aromatic diamine represented by formula (III) 0.
51 to 0.99 mol, 0.49 to 0.01 mol of thioether aromatic diamine represented by formula (IV), and formula (V
) Aromatic polycarboxylic dianhydride 0.90~
1.10 mol (preferably 0.95-1.05 mol)
A polyamic acid solution is obtained by dissolving and mixing in an organic solvent at -20 to +80°C (preferably -1O to +60°C) (first step).

The organic polar solvents used in this step include aprotic polar solvents (N,N-dimethylformamide, N,N-
Dimethylacetamide, N,N-dimethylpropionamide, N,N-dimethylbenzamide, N-methylpyrrolidone, N-methylpiperidone, N-methyl-ε-caprolactam, hexamethylphosphoramide, tetramethylurea, 1,3-dimethyl -2-imidazolidinone,
sulfolane, dimethyl sulfoxide, etc.); aliphatic glycol ethers (ethylene glycol dimethyl ether,
(diethylene glycol dimethyl ether, etc.); and mixtures thereof. Among these, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, sulfolane, diethylene glycol dimethyl ether and the like are particularly preferred.

vinegar 1i) l'lmid production process (second process).

The polyamic acid obtained in the first step above is dehydrated and ring-closed,
It is converted into the aromatic polyimide copolymer of the present invention (second step). This operation may be performed in either a liquid phase state or a solid phase state.

Ring closure methods in a liquid phase include thermal ring closure methods and chemical ring closure methods.

The thermal ring-closing method is a method in which a polyamic acid solution is heated to 50 to 400°C, preferably 150 to 250°C, and at this time, an azeotropic solvent (such as benzene, toluene, xylene, chlorobenzene, etc. ) and/or a catalyst (for example, p-toluenesulfonic acid, benzenesulfonic acid, etc.) is more effective.

The chemical ring closure method uses fatty acid anhydrides (acetic anhydride, propionic anhydride, etc.) - tertiary amines (triethylamine, pyridine,
4-dimethylaminopyridine, isoquinoline, etc.); halogen compounds (phosphorus oxychloride, thionyl chloride, etc.); chemical dehydrating agents (molecular sieve, silica gel, alumina, phosphorus pentoxide, etc.), etc. are added to the polyamic acid solution, and
The reaction is carried out at 120°C, preferably 10-80"C.

The aromatic polyimide copolymer produced by ring closure in a liquid phase may precipitate or remain in a solution state. If it precipitates, it can be isolated by filtering it, but if it remains in a solution state, it can be diluted with a solvent that does not dissolve the polymer and is easily compatible with the reaction solvent to precipitate the polymer. It is isolated by filtering it.

On the other hand, the ring closure method in a solid phase state is achieved by first introducing a polyamic acid solution into water or methanol, precipitating and separating the polymer, and heat-treating it at 150 to 350°C. However, care must be taken because if the treatment is carried out at a high temperature of 250° C. or higher for too long, the fluidity during melting and the balance of mechanical properties will deteriorate.

Specific examples of the ether aromatic diamine represented by the formula (I [ .4-bis(3-aminophenoxy)
Benzene, 1,4-bis(4-aminophenoxy)benzene, 2-methyl-1,4-bis(4-aminophenoxy)benzene, 4.4'-bis(3-aminophenoxy)biphenyl, 4°4' -bis(4-aminophenoxy)biphenyl, 3,3'-dibromo-4,4'-bis(
4-aminophenoxy)biphenyl, 4,4'-bis(
3-aminophenoxy)diphenyl sulfide, 4.4
'-Bis(4-aminophenoxy) diphenyl sulfide, 4.4'-bis(3-aminophenoxy)benzophenone, 4.4'-bis(4-aminophenoxy)benzophenone, 4.4'-bis(3-amino phenoxy)
Diphenyl ether, 4.4'-bis(4-aminophenoxy)diphenyl ether, 4.4'-bis(3-aminophenoxy)diphenyl sulfoxide, 4.4'-
Bis(4-aminophenoxy)diphenylsulfoxide, 4.4'-bis(3-aminophenoxy)diphenylsulfone, 4.4'-bis(4-aminophenoxy)diphenylsulfone, 3.3'-bis(4-amino phenoxy)diphenylsulfone, 4.4'-dinitro-3゜3'-bis(3-aminophenoxy)diphenylsulfone, 2.2'-bis(4-(4-aminophenoxy)phenyl]propane, 2.2' -bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis(4-
(4-aminophenoxy)phenylcomethane, 414'
-(m-phenylenediisopropylidene)bisaniline, 4.4' -(p-phenylenediisopropylidene)bisaniline, 3°3'-(m-phenylenediisopropylidene)bis72'J 7.3.3' -(p-phenylenediisopropylidene)bisaniline, and the like.

At least one of these is used. Also, the formula (I[
The amount of diamine represented by l) used is: 51 to 99 mol%.

On the other hand, specific examples of the 1,000-onythyl aromatic diamine represented by the formula (IV) include 1,4-bis(4-aminophenylthio)benzene, 3-bis(4-aminophenylthio)benzene, 2.4-bis(aminophenylthio)nitrobenzene, 2.5-dimethyl-1,4-bis(4-aminophenylthio)benzene, 4.4'-bis(4-aminophenylthio)biphenyl, 4.4 '-bis(4-aminophenylthio)diphenyl ether, 4
．． 4'-bis(4-aminophenylthio)diphenyl sulfide, 1,4-bis(4-(4-aminophenylthio)phenylthio)benzene, α,ω-diaminopoly
(1,4-thiophenylene) oligomer, 4.4'-bis(4-aminophenylthio)benzophenone, 4.4
'-Bis(4-aminophenylthio)diphenylsulfoxide, 4,4'-bis(4-aminophenylthio)diphenylsulfone, 3,3'-bis(4-aminophenylthio)diphenylsulfone, 2,2-bis (4-(4
-aminophenylthio)phenyl)propane, 4.4'
-bis(4-aminophenylthio)diphenylmethane,
etc. can be mentioned.

At least one of these is used.

Further, the amount of diamine represented by formula (IV) used is 49 to
It is 1 mol%.

Specific examples of the aromatic polycarboxylic acid anhydride represented by the formula (V) used in the present invention include pyromellitic dianhydride, 3.3', 4.4'-bisphenyltetracarboxylic Acid dianhydride, 3.3', 4.4'
-diphenyl ether tetracarboxylic dianhydride, 31
3'14.4'-Diphenylsulfidetetracarboxylic dianhydride, 3.3', 4.4'-benzophenonetetracarboxylic dianhydride, 3.3', 4.4
'-Diphenylsulfonetetracarboxylic dianhydride, 3
．． 3',4.4'-benzanilidetetracarboxylic dianhydride, 1,4-bis(3,4-dicarboxyphenyl)benzene dianhydride, 4.4'-bis(3,4-
dicarboxyphenyl)biphenyl dianhydride, 4.4'
-bis(3,4-dicarboxyphenyl)diphenylsulfone dianhydride, 2,2-bis(4-(3,4-dicarboxyphenoxy)phenyl)propani dianhydride, 4.
4'-bis(3,4-dicarboxyphenoxy)diphenyl ether dianhydride, 4.4'-bis(3,4-dicarboxyphenoxy)penzophenone dianhydride, 4.4
'-Bis(3,4-dicarboxyphenylthio)diphenylsulfone dianhydride, 4.4'-bis(3,4-dicarboxyphenylthio)biphenyl dianhydride, 4.4'
-bis(3゜4-dicarboxybenzoyl)penzophenone dianhydride Th, 4,4'-bis(3,4-dicarboxybenzenesulfonyl)diphenylsulfone dianhydride,
4.4'-bis(3,4-dicarboxybenzamide)
Diphenyl ether dianhydride, etc. can be mentioned.

At least one of these is used.

The thus obtained aromatic compound consists of 51 to 99 mol% of the total repeating unit represented by the formula (I) and 49 to 1 mol% of the total repeating unit represented by the formula (II). The polyimide copolymer has a glass transition temperature of 100~
The temperature is 350°C (preferably 150 to 300°C).

[Processing/Applications]

When molding the polymer of the present invention, various known filler components can be included. Typical examples of filler components include (a) fibrous fillers such as glass fiber, carbon fiber,
Boron fiber, aramid fiber, alumina fiber, silicon nicarbide fiber, etc. (b) Inorganic filler: mica,
Examples include talc, clay, graphite, carbon black, silica, asbestos, molybdenum sulfide, magnesium oxide, and calcium oxide.

The polymer of the present invention can be used in a wide range of applications, including various parts in the electrical and electronic fields, housings, automobile parts, aircraft interior materials, sliding parts, gears, insulating materials, heat-resistant films, heat-resistant panels, and heat-resistant fibers. Is possible.

〔Example〕

Next, the present invention will be explained in more detail with reference to examples, but the scope of the present invention is not limited by these examples.

・Example 1 10100O? equipped with a thermometer, a water separator with a Dimroth cooling tube, a solid inlet, and a nitrogen gas inlet. 25.9 g (0.06 mol) of 4,4'-bis(4-7mi/phenoxy)diphenylsulfone was added to a 4-volume four-hole flask.
17.3 g (0.04 mol) of 4'-bis(4-aminophenylthio)diphenyl sulfide and 200 mf of dry N-methylpyrrolidone were charged. Next, under a nitrogen stream,
3.3',4.4'-Biphenyltetracarboxylic dianhydride 29.5g (0.10 mol) was heated to an internal temperature of 30
The mixture was added while maintaining the temperature below ℃.

Subsequently, the mixture was stirred at room temperature for 20 hours. Thereafter, the reaction mixture was diluted with 600 mJ of dry N-methylpyrrolidone, and then 8.1 ml (0.10 mol) of pyridine and 45.3 ml (0.41 mol) of acetic anhydride were added, keeping the internal temperature at 70°C. The mixture was added while stirring, and stirring was further continued at 70°C for 2 hours. After cooling to room temperature, acetone was added to the reaction mixture, and the precipitated polymer was filtered off, washed with acetone, and then dried in a vacuum oven.

(180°C, 24 hours).

Yield: 69.0 g (yield: 99.9%). Soluble in organic solvent (N-methylpyrrolidone). Glass transition temperature 268°C.

IR spectrum (KBr): 1770.1715
am-' (imide), 1230 c+n-' (ether), 1145 am-' (sulfone), 1075
am-' (thioether), 825°730 am
−' (aromatic ring).

This polymer could be compression molded at 380°C, and a brown resin plate was obtained.

- Comparative Example 1 In Example 1, 4.4'-bis(4-
aminophenoxy) diphenylsulfone 43.2g (0
, 10 mol) was used, but the polymerization was carried out in the same manner as in Example 1.

Yield: 69.1 g (yield 100%). Poorly soluble in organic solvents (N-methylpyrrolidone). Glass transition temperature 288°C.

IR spectrum (KBr): 1780.1720
cm-' (imide), 1240 cm-' (ether), 1150 cm-' (sulfone), 835.7
40 am-' (aromatic ring).

Compression molding of this polymer required 420°C, Example 1
Compared to the gap in glass transition temperature (20°C), the gap in temperature at which compression molding is possible was much larger (40°C), and the moldability was inferior.

・Example 2 In Example 1, 1,4'-bis(4-
Same as Example 1 except that 17.5 g (0.06 mol) of aminophenoxy)benzene and 18.6 g (0.04 mol) of 4,4'-bis(4-aminophenylthio)diphenylsulfone were used. Polymerization was carried out using the following method.

Yield 61.8g (yield 99.7%). Insoluble in organic solvent (N-methylpyrrolidone). Glass transition temperature 297°C.

IR spectrum (KBr): 1780.1720
crn-' (imide), 1225 as-' (ether), 1155 an-' (sulfone), 1080
cm-' (thioether), 830°765, 74
0 cm-' (aromatic ring).

This polymer could be compression molded at 400°C, and a brown resin plate was obtained. Although the glass transition temperature was about 10° C. higher than that of Comparative Example 1, it could be molded at a temperature 20° C. lower, and the molding processability was excellent.

・Example 3 In Example 1, 2,2-bis(4-(
4-aminophenoxy)phenyl]propane 24.6
g (0,06 mol) and 17.3 g (0,06 mol) of 4,4'-bis(4-aminophenylthio)diphenyl sulfide.
04 mol) and 3.3', 4.4 as anhydride.
'-benzophenone tetracarboxylic dianhydride 32.
Polymerization was carried out in the same manner as in Example 1, except that 2 g (0.10 mol) was used.

Yield: 70.1 g (yield: 99.4%). is insoluble in the organic solvent (N-methylpyrrolidone). Glass transition temperature 241°C. Thermal decomposition starting temperature is 447°C (in air).

IR spectrum (KBr): 1780, 1720
cm-' (imide), 1660 ell-' (
ketone), 1235 cm-' (ether), 10
80 am-' (thioether), 830°720
am-' (aromatic ring).

This polymer could be compression molded at 340°C, yielding a light amber transparent resin plate.

Also, the tensile strength (yield point) is 8801qr/co! , the tensile modulus was 29.300 kg/ci, and it was extremely tough.

・Comparative Example 2 In Example 3, 2,2-bis(4-(
4-aminophenoxy)phenyl]propane 41.0g
Polymerization was carried out in the same manner as in Example 3, except that (0.10 mol) was used.

Yield: 69.6 g (yield 100%). Insoluble in organic solvent (N-methylpyrrolidone). Glass transition temperature 246°C. Thermal decomposition starting temperature is 453°C (in air).

IR spectrum (KBr): 1780.1720
an-" (imide), 1665 am-' (ketone), 1240 am-' (ether), 825.
720 cm-' (aromatic ring).

This polymer requires 360°C for compression molding and has a glass transition temperature gap of 5°C compared to the polymer of Example 3.
Compared to this, the temperature gap (20° C.) at which compression molding was possible was large, and the molding processability was inferior. Further, discoloration occurred during molding, and thermal stability was also insufficient.

- Example 4 In Example 3, 20.6 g of 4.4'-(m-phenylene diisopropylidene) bisaniline was used as the diamine (
Polymerization was carried out in the same manner as in Example 3, except that 16.0 g (0.04 mol) of 4,4'-bis(4-aminophenylthio)biphenyl were used.

Yield: 68.5 g (yield: 99.6%). Insoluble in organic solvent (N-methylpyrrolidone). Glass transition temperature 226°C.

IR spectrum (KBr): 1775.1710
cn-' (imide), 1660 cm-' (ketone), 1080 an-' (ether), 850
．． 825.810.7050-1 (aromatic ring).

This polymer can be compression molded at 340°C, and a wet orange transparent and strong resin plate could be obtained.

・Example 5 10100O with thermometer, water separator with Dimroth cooling pipe, solid inlet, and nitrogen gas inlet! 20.4 g (0.07 mol) of 1,3-bis(4-aminophenoxy)benzene and 4°4'-bis(4-
Aminophenylthio)biphenyl 12.0g (0.03
mol) and 200 ml of dry N-methylpyrrolidone. Next, under a nitrogen stream, 25.8 g of 3.3',4.4'-benzophenonetetracarboxylic dianhydride
(0.08 mol) and 4.4 g of pyromellitic dianhydride
(0.02 mol) was added while keeping the internal temperature below 30°C. Subsequently, the mixture was stirred at room temperature for 20 hours. Then p-
Toluenesulfonic acid 0. ．． 1 g (0,0053 mol), 450 ml of dry N-methylpyrrolidone. xylene 1
00ml and heated to 180℃ for 1 hour.
Stirred at this temperature for 8 hours. Note that the water produced at this time was removed by azeotropy with xylene. After cooling to room temperature, the reaction mixture was poured into water to precipitate the polymer, which was filtered off, ground, washed with water, and then dried in a vacuum oven. (
180°C, 24 hours).

Yield: 59.0 g (yield: 100%). Insoluble in organic solvent (N-methylpyrrolidone). Glass transition temperature 263°C.

IR spectrum (KBr): 1780.1720
am-' (imide), 1665 cm-' (ketone), 1210 c+n-' (1-tel), 10
90 crn-' (thioether), 855°8
25, 720.705 cm-' (aromatic ring).

This polymer could be compression molded at 370°C, and a strong brown resin plate was obtained.

[Brief explanation of the drawing]

Figure 1 shows the infrared absorption spectrum of the aromatic polyimide copolymer obtained in Example 2, and Figure 2 shows the infrared absorption spectrum of the aromatic polyimide copolymer obtained in Example 5. be. Patent applicant Mitsubishi Yuka Co., Ltd.

Claims (3)

[Claims] (1) An aromatic polyimide copolymer comprising 51 to 99 mol% of the total repeating units represented by the following formula (I), and 49 to 1 mol% of the total comprising repeating units represented by the following formula (II). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) (In the formula, -X- represents -O-, ▲There are mathematical formulas, chemical formulas, tables, etc.) , -Ar_1- and -Ar_4- are divalent aromatic residues, and ■Ar_2■ is a tetravalent aromatic residue.) (2) Divalent aromatic residues are as follows: ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲mathematical formulas, chemical formulas,
There are tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas, chemical formulas,
There are tables, etc. ▼ (In the formula, A is O, CO, SO, SO_2, C_yH_2
Either _y. However, y is an integer of 1 to 10, Y is an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, Represents a halogen group or a nitro group. a, b, c, d, e, and f represent integers of 0 to 4. x represents a number from 0 to 20. ) The copolymer according to claim 1, which is selected from the following. (3) Tetravalent aromatic residues are as follows: ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲mathematical formulas, chemical formulas,
There are tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (-B_1-, -B_2- are -O-, -S-, -CO
-, -SO_2-, ▲There are mathematical formulas, chemical formulas, tables, etc.▼
, either. Further, a and a' are 0 or 1. -Ar_4- is a divalent aromatic residue. ) The copolymer according to claim 1, which is selected from the following.