JP2748992B2 - Crystalline polyimide and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyimide for melt molding. More specifically, the present invention relates to a crystalline polyimide for melt molding having excellent moldability and a method for producing the same.

[0002]

2. Description of the Related Art A polyimide obtained by reacting a tetracarboxylic dianhydride with a diamine has extremely high heat resistance, and also has excellent mechanical strength and dimensional stability, flame retardancy,
Also excellent in electrical insulation. Since polyimide has such preferable performance, conventionally, it has been used in the fields of electric / electronic equipment, aerospace equipment, transportation equipment, etc., and in the future, will be increasingly used in fields where heat resistance is required. It is a functional resin that is expected to be used. With the expansion of such fields of application, the required application methods have been diversified, and various polyimides exhibiting excellent properties that meet these requirements have been developed.

However, these polyimides include:
Some have excellent heat resistance but do not have a clear glass transition temperature, so if they are used as molding materials, they must be processed using techniques such as sintering. However, they are soluble in solvents such as halogenated hydrocarbons and have problems in solvent resistance, and polyimides that have already been developed have advantages and disadvantages in their performance.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a crystalline polyimide for melt molding which has excellent processability and good chemical resistance in addition to the excellent heat resistance inherent to polyimide. That is.

[0005]

Means for Solving the Problems The present inventors have made intensive studies in order to solve this object, and as a result, completed the present invention. That is, according to the present invention, the polymer molecule terminal is blocked with phthalic anhydride,

Embedded image A crystalline polyimide for melt molding, comprising a repeating structural unit represented by the following formula, wherein the terminal of the polymer molecule is represented by formula (3a) or (3b):

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[0006] And this polyimide is represented by the following formula (4)

Embedded image 3,4'-diaminodiphenyl ether represented by the formula (b): Formula (5)

Embedded image 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride represented by the formula: (c) Formula (1)

Embedded image With phthalic anhydride represented by

(D) The amount of the phthalic anhydride of the formula (1) is 0.001 to 1.0 mole per mole of the 3,4'-diaminodiphenyl ether of the formula (4), and the polyamic acid obtained by the reaction is heated. Obtained chemically or chemically by imidization,
This is a method for producing a crystalline polyimide for melt molding, comprising a repeating structural unit of the formula (2), and the terminal of the polymer molecule represented by the formula (3a) or (3b).

Embedded image

Embedded image

In the polyimide of the present invention, the molecular terminal of the polymer is represented by the formula (1)

Embedded image And sealed with phthalic anhydride represented by the formula (2)

Embedded image This is a crystalline polyimide for melt molding, which comprises a repeating structural unit represented by the following formula, and the terminal of the polymer molecule is represented by the formula (3a) or (3b).

Embedded image

Embedded image

The polyimide of the present invention has the formula (4)

Embedded image 3,4′-diaminodiphenyl ether represented by the formula (5)

Embedded image 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride represented by the formula (1)

Embedded image Can be produced by thermally or chemically imidizing a polyamic acid obtained by reacting with phthalic anhydride represented by

The polyimide of the present invention uses 3,4'-diaminodiphenyl ether as a raw material as a diamine component, but may be mixed with other diamines within a range that does not impair the good physical properties of the polyimide. Can also be used. As a diamine that can be used by mixing,
For example, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether,
2,2'-diaminodiphenyl ether, 2,3'-diaminodiphenyl ether, 2,4'-diaminodiphenyl ether, bis (3-aminophenyl) sulfide, (3-aminophenyl) (4-aminophenyl) sulfide, bis (4 -Aminophenyl) sulfide, bis (3-aminophenyl) sulfoxide, (3-aminophenyl)
(4-aminophenyl) sulfoxide, bis (4-aminophenyl) sulfoxide, bis (3-aminophenyl) sulfone, (3-aminophenyl) (4-aminophenyl) sulfone, bis (4-aminophenyl) sulfone, 3 , 3'-Diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-
Diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, bis [4-
(3-aminophenoxy) phenyl] methane, bis [4
-(4-aminophenoxy) phenyl] methane, 1,1-
Bis [4- (3-aminophenoxy) phenyl] ethane, 1,1-bis [4- (4-aminophenoxy) phenyl] ethane, 1,2-bis [4- (3-aminophenoxy) phenyl] ethane, 1,2-bis [4- (4-aminophenoxy) phenyl] ethane, 2,2-bis [4- (3
-Aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane,
2,2-bis [4- (3-aminophenoxy) phenyl]
Butane, 2,2-bis [4 (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2
-Bis [4 (4-aminophenoxy) phenyl] -1,1,
1,3,3,3-hexafluoropropane,

1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene,
1,4-bis (3-aminophenoxy) benzene, 1,4-
Bis (4-aminophenoxy) benzene, 4,4′-bis (3-aminophenoxy) biphenyl, 4,4′-bis (4
-Aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (4-
Aminophenoxy) phenyl] ketone, bis [4- (3
-Aminophenoxy) phenyl] sulfide, bis [4
-(4-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfoxide, bis [4- (4-aminophenoxy) phenyl]
Sulfoxide, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (4 -Aminophenoxy) phenyl] ether, 1,4-bis [4-
(3-aminophenoxy) benzoyl] benzene, 1,3
-Bis [4- (3-aminophenoxy) benzoyl] benzene, 4,4'-bis [3- (4-aminophenoxy) benzoyl] diphenyl ether, 4,4'-bis [3- (3
-Aminophenoxy) benzoyl] diphenyl ether, 4,4'-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] benzophenone, 4,4'-bis [4- (4-amino-α, α -Dimethylbenzyl) phenoxy] diphenylsulfone, bis [4- {4- (4-aminophenoxy) phenoxy} phenyl] sulfone, bis [4- {4- (4-aminophenoxy) phenoxy}
Phenyl] sulfone, 1,4-bis [4- (4-aminophenoxy) -α, α-dimethylbenzene, 1,3-bis [4- (4-aminophenoxy) -α, α-dimethylbenzene and the like. These may be used alone or in combination of two or more.

Further, it is not possible to substitute a part of the phthalic anhydride represented by the formula (1) for use in the present invention with another dicarboxylic anhydride as long as the good physical properties of the polyimide are not impaired. No problem. Examples of the dicarboxylic anhydride that can be used as a partial substitute include 2,3-benzophenone dicarboxylic anhydride, 3,4-benzophenone dicarboxylic anhydride, 2,3-dicarboxyphenylphenyl ether anhydride, 4-dicarboxyphenylphenyl ether anhydride, 2,3-biphenyldicarboxylic anhydride, 3,4-biphenyldicarboxylic anhydride, 2,3-dicarboxyphenylphenylsulfone anhydride, 3,4-dicarboxyphenylphenyl Sulfone anhydride, 2,3-dicarboxyphenylphenyl sulfide anhydride, 3,4-dicarboxyphenylphenyl sulfide anhydride, 1,2-
Naphthalenedicarboxylic anhydride, 2,3-naphthalenedicarboxylic anhydride, 1,8-naphthalenedicarboxylic anhydride, 1,2-anthracenedicarboxylic anhydride, 2,3-anthracenedicarboxylic anhydride, 1,9- And anthracene dicarboxylic anhydride.

The amount of phthalic anhydride used in the present invention is 0.001 to 1.0 mol per mol of 3,4'-diaminodiphenyl ether represented by the formula (4).
If the amount is less than 0.001 mol, an increase in viscosity is observed during high-temperature molding, which causes a reduction in moldability. On the other hand, if it exceeds 1.0 mol, the mechanical properties deteriorate. The preferred amount is 0.01 to 0.5.
It is a mole ratio.

The production of the polyimide of the present invention is particularly preferably carried out in an organic solvent. Examples of the organic solvent used include N, N-dimethylformamide and N, N-
Dimethylacetamide, N, N-diethylacetamide,
N, N-dimethylmethoxyacetamide, N-methyl-2
-Pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-methylcaprolactam, 1,2-dimethoxyethanebis (2-methoxyethyl) ether, 1,2-bis (2-methoxyethoxy) ethane, bis ｛ 2- (2-methoxyethoxy) ethyl ether, tetrahydrofuran, 1,3-dioxane, 1,4-dioxane, pyridine,
Picoline, dimethyl sulfoxide dimethyl sulfone, tetramethyl urea, hexamethyl phosphoramide, phenol, o-cresol, m-cresol, p-cresol, m-cresylic acid, p-chlorophenol, anisole and the like. These organic solvents may be used alone or in combination of two or more.

In the method of the present invention, 3,4 ′ is added to the organic solvent.
-Diaminodiphenyl ether, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and phthalic anhydride can be added and reacted as follows: (a) 3,3', 4,4'-biphenyltetracarboxylic After reacting acid dianhydride with 3,4'-diaminodiphenyl ether, phthalic anhydride is added to continue the reaction. (B) 3,4'-diaminodiphenyl ether is added with phthalic anhydride to react. After that, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride is added and the reaction is further continued. (C) 3,3', 4,4'-biphenyltetracarboxylic dianhydride , 3,4'-diaminodiphenyl ether and phthalic anhydride may be added simultaneously to cause a reaction.

The reaction temperature is usually 250 ° C. or lower, preferably 50 ° C.
It is below ° C. The reaction pressure is not particularly limited, and the reaction can be sufficiently performed at normal pressure. The reaction time varies depending on the type of the solvent and the reaction temperature, and usually 4 to 24 hours is sufficient. Further, the obtained polyamic acid is heated to 100 to 400 ° C. to be imidized, or is chemically imidized using an imidizing agent such as acetic anhydride to obtain a polyimide having a repeating structural unit corresponding to the polyamic acid. Is obtained.

Also, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and 3,4'-diaminodiphenyl ether,
It is also possible to obtain a polyimide by suspending or dissolving phthalic anhydride in an organic solvent, heating, and performing imidation simultaneously with generation of the polyamic acid, which is a precursor of the polyimide. That is, polyimide in the form of a film or powder can be obtained using a conventionally known technique.

When the polyimide of the present invention is subjected to melt molding, other thermoplastic resins such as polyethylene, polypropylene, polycarbonate, polyarylate, polyamide, polysulfone, polyethersulfone and the like can be used as long as the object of the present invention is not impaired. An appropriate amount of polyether ketone, polyphenylene sulfide, polyamide imide, polyether imide, modified polyphenylene oxide or the like can be blended according to the purpose.

Further, the following fillers and the like used in ordinary resin compositions may be used to the extent that the object of the invention is not impaired. In other words, graphite, carborundum, silica powder, molybdenum disulfide, abrasion resistance improvers such as fluororesin, glass fiber, carbon fiber, boron fiber, silicon carbide fiber, carbon whisker, asbestos, metal fiber, ceramic fiber, etc. Materials, flame retardant improvers such as antimony trioxide, magnesium carbonate, calcium carbonate, and electrical property improvers such as clay and mica,
Tracking resistance improver such as asbestos, silica, graphite, acid resistance improver such as barium sulfate, silica, calcium metasilicate, thermal conductivity improver such as iron powder, zinc powder, aluminum powder, copper powder, other glass beads,
Glass spheres, talc, diatomaceous earth, alumina, shirasubarun, hydrated alumina, metal oxides, coloring agents and the like.

[0020]

The present invention will now be described by way of Examples and Comparative Examples.
This will be described in more detail. The physical properties in Examples and Comparative Examples were measured by the following methods. Tg, Tc, Tm; Measured with (Shimadzu DT-40 series, DSC-41M) 5% weight loss temperature; Measured with DTG (Shimadzu DT-40 series, DTG-40M) in air Melt viscosity; Measured with a flow tester CFT500A at a load of 100 kg

Example 1 120.0 g of 3,4'-diaminodiphenyl ether was placed in a vessel equipped with a stirrer, a reflux condenser, a water separator and a nitrogen inlet tube.
(0.6 mol), 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride 169.3 g (0.576 mol), phthalic anhydride 7.10 g
(0.048 mol), γ-picoline 8.4 g, m-cresol 12
145 g with stirring under a nitrogen atmosphere.
The temperature was raised to ℃. During this time, distillation of about 20 cc of water was confirmed. Further, the reaction was carried out at 140 to 150 ° C. for 4 hours. Thereafter, the mixture was cooled to room temperature and discharged into about 10 liters of methyl ethyl ketone, and then the polyimide powder was separated by filtration. After washing this polyimide powder with methyl ethyl ketone,
After drying under reduced pressure for 27 hours, 271.0 g (98.6%) of polyimide powder was obtained. The logarithmic viscosity of the polyimide powder thus obtained is 0.60
dl / g.

The logarithmic viscosity is a value measured at 35 ° C. after heating and dissolving 0.50 g of polyimide powder in 100 ml of a mixed solvent of p-chlorophenol / phenol (weight ratio: 9/1). The glass transition temperature of this polyimide powder is (Tg)
247 ° C, crystallization temperature (Tc) 275 ° C, crystal melting temperature 401
° C and the 5% weight loss temperature in air was 557 ° C. FIG. 1 shows an infrared absorption spectrum of this polyimide powder. This spectrum diagram, the absorption near 1240 cm ^-1 is 1780 cm ^-1 and 1720 cm ^-1 and near the characteristic absorption band of ether linkage is imide characteristic absorption bands were remarkably observed. The elemental analysis values of the obtained polyimide powder were as follows.

This polyimide powder is composed of methylene chloride,
It was insoluble in halogenated hydrocarbon solvents such as chloroform. The melt viscosity of the polyimide powder obtained in this example was measured using a Koka type flow tester with a load of 100 kg and an orifice having a diameter of 0.1 cm and a length of 1 cm. Four
The melt viscosity at 20 ° C. was 8,100 poise. The strand obtained here was light yellow and highly flexible. Further, the molding stability of the polyimide obtained in this example was measured by changing the residence time in the cylinder of the flow tester. The temperature was 420 ° C. and the load was 100 kg. Figure 2 shows the results.
Shown in Even if the residence time in the cylinder becomes longer, the melt viscosity hardly changes, indicating that the thermal stability is good.

Comparative Example 1 In the same reactor as in Example 1, 120.0 g (0.6 mol) of 3,4'-diaminodiphenyl ether, 125.57 g (0.576 mol) of pyromellitic dianhydride, 7.10 g (0.048 g) of phthalic anhydride Mol), 8.4 g of γ-picoline and 980 g of m-cresol, and polyimide powder 228.8 was prepared in the same manner as in Example 1.
g (99.0%). This polyimide powder had no clear glass transition temperature and did not melt and flow at 420 ° C.

Comparative Example 2 A polyimide powder was obtained in exactly the same manner as in Example 1 except that phthalic anhydride was not used. The glass transition temperature of polyimide powder is
At 246 ° C., the logarithmic viscosity was 0.60 dl / g. When the residence time in the flow tester cylinder was changed and the melt viscosity was measured in the same manner as in Example 1, the melt viscosity increased as the residence time became longer as shown in FIG.
The thermal stability was inferior to the polyimide obtained in the above.

Example 2 In a vessel equipped with a stirrer, a reflux condenser and a nitrogen inlet tube,
12.00 g (0.06 mol) of 3,4'-diaminodiphenyl ether, 118.6 g of N, N-dimethylacetamide, 3,3 ',
4,4'-biphenyltetracarboxylic dianhydride 17.47 g
(0.0594 mol) was added in portions, paying attention to the rise in solution temperature, and stirred at room temperature for about 20 hours. Thereafter, 0.177 g (1.2 × 10 ⁻³ mol) of phthalic anhydride was added, and stirring was further continued for 3 hours. The logarithmic viscosity of the polyamic acid thus obtained was 1.06 dl / g. The logarithmic viscosity of polyamic acid is 0.5 g / N, N-dimethylacetamide as a solvent.
This is a value measured at 35 ° C in a 100 ml solvent. After taking a part of this polyamic acid solution and casting it on a glass plate, 100
℃, 200 ℃ and 250 ℃ for 1 hour each, about 50 thickness
A μm polyimide film was obtained. The tensile strength of this polyimide film is 16.1kg / mm ² , tensile modulus 340kg
/ Mm ² , and the tensile elongation was 5.7%. (Measurement method is AS
TM D-822).

[0027]

The polyimide of the present invention uses 3,4'-diaminodiphenyl ether as a diamine component and 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride as a tetracarboxylic dianhydride component. Characterized by using
It is a crystalline polyimide for melt molding that is thermoplastic while having excellent heat resistance and is excellent in processability. Furthermore, the polyimide of the present invention has excellent chemical resistance. Considering the above-mentioned excellent workability, it can be used as a base material for space and aircraft, a base material for electric and electronic parts, and a heat-resistant adhesive. It is a very useful polyimide as an agent. As described above, the polyimide of the present invention is a crystalline polyimide which is superior in melt flow stability as compared with conventionally known polyimides and has greatly improved moldability.

[Brief description of the drawings]

FIG. 1 is a diagram of an infrared absorption spectrum of a polyimide powder obtained in Example 1.

FIG. 2 shows the molding stability of the polyimide powder obtained in Example 1 compared with the polyimide powder obtained in Comparative Example 2 at a temperature of 420.
FIG. 6 is a diagram showing the results of measurement at a temperature of 100 ° C. and a load of 100 kg while changing the residence time in the cylinder of the flow tester.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-215024 (JP, A) JP-A-62-27733 (JP, A) JP-A-61-95029 (JP, A) JP-A-2- 18419 (JP, A) JP-A-59-170122 (JP, A) JP-B-38-5997 (JP, B1) JP-A-63-500870 (JP, A) APPL. POLYM. SCI. , 32 (1) 3133-3149 (34 DDE + BPDA). A. ADROVA, ETC "PO LYIMIDES A NEW CLASS OF HEAT-RESISTANT NT POLYMERS" (ISRAE L PROGRAM FOR SCIE NTIFIC TRANSLATION S JERUSALEM 1969) "Polymer Shinsaku Tatsuo Kataoka" Kyoritsu Shuppan) 92 pages (58) Field surveyed (Int. Cl. ⁶ , DB name) C08G 73/10 CA (STN)

Claims (2)

(57) [Claims] 1. A polymer molecule having a terminal represented by the formula (1) : Embedded image with phthalic anhydride represented by the formula (2) In Ri Do repeating structural unit represented by, the polymer content
Melt molding in which the ends of the child are formulas (3a) and (3b)
Crystalline polyimide for use . Embedded image Embedded image 2. (a) Formula (4) 3,4'-diaminodiphenyl ether represented by the formula : (b) Formula (5) 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride represented by the following formula : and (c) a compound represented by the formula (1) : And phthalic anhydride represented in the amount of phthalic anhydride (d) formula (1) has the formula (4) of 3,4 '
-0.001 to 1. per mole of diaminodiphenyl ether.
The polyamic acid obtained by reacting at 0 mole
Or a compound of formula (2) obtained by chemically imidizing Consisting of a repeating structural unit represented by
For melt molding is terminated formula child (3a) Contact and (3b)
A method for producing a crystalline polyimide. Embedded image Embedded image