JPH05170906A - Amorphous polyimide powder and its production - Google Patents

Abstract

PURPOSE:To obtain amorphous polyimide powder having excellent moldability, processability and adhesiveness, containing a polymer molecule end hindered with a dicarboxylic acid anhydride by reacting a diamine with a tetracarboxylic acid dianhydride and a dicarboxylic acid anhydride. CONSTITUTION:(A) 1mol 3,3'-diaminobenzophenone of formula I is reacted with (B) 0.8-lmol 3,3',4,4'-benzophenonetetracarboxylic acid dianhydride of formula II and (C) 0.001-1mol dicarboxylic acid anhydride of formula III (Z is 6-27C bifunctional group such as monocyclic aromatic group or condensed polycyclic aromatic group) in the presence of 10-1,000mol% based on the component B of an organic solvent (preferably phenolic solvent) at 100-400 deg.C and the prepared polymer is discharged to a poor solvent (0.5-10 times as much as the organic solvent) uniformly mixable with the organic solvent to give amorphous polyimide powder comprising a repeating structural unit of formula IV as a basic skeleton, having a polymer molecule end hindered with a dicarboxylic acid anhydride of formula III, not containing a reactive group at the polymer molecule end.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to amorphous polyimide powder. More specifically, it relates to an amorphous polyimide powder having good thermal stability and moldability, a method for producing the powder, and a heat-resistant adhesive and a bonding method using the powder.

[0002]

2. Description of the Related Art Conventionally, a polyimide obtained by the reaction of a tetracarboxylic dianhydride and a diamine has not only high heat resistance but also excellent mechanical strength and dimensional stability, flame retardancy, and electrical insulation. In order to have both, it is used in the fields of electrical and electronic equipment, aerospace equipment, transportation equipment, etc., and is expected to be widely used in the fields where co-heat resistance is required in the future.

Conventionally, various polyimides having excellent characteristics have been developed. In particular, the formula (1)

[Chemical 13] The polyimide represented by has already been found by Proger et al. (USP 4,065,345), as a polyimide showing excellent mechanical properties, thermal properties, electrical properties, solvent resistance, heat resistance, and melt flowability. Was known. But,
This polyimide also has a higher melt viscosity than engineering plastics other than ordinary extrusion-moldable and injection-moldable polyimides, and injection molding, extrusion molding and the like were difficult.

In order to solve these problems, the present applicants basically have the basic structure of the above formula (1) and regulate the molecular weight of the polymer by sealing the end of the reactive polymer. Then, a polyimide that can be injected and extruded was found (JP-A-2-018419). However, this polyimide is also Ohta et al, 35th International
As disclosed in SAMPE Symposium, April 2-5, P1030 (1990), it has a melting point near 360 ° C and must be amorphized in order to be used for molding and bonding at low temperature. It had drawbacks. The polyimide of the above formula (1) can be used as an adhesive having excellent heat resistance, and is currently mainly used for adhesion of metal, prepreg, ceramics, etc., adhesion of polyimide film for FPC substrate, etc. However, due to its thermoplasticity, it is expected to develop as a wider adhesive.

The conventional adhesion techniques are as follows: 1) a method in which a polyamic acid varnish as a precursor is applied to the adhesive surface, and pressure and heat are applied to remove the solvent and imidize, and 2) a polyimide film is applied to the adhesive surface. Method of adhering by scissors, pressurization, heating, 3) Suspending polyimide powder in a solvent that easily volatilizes (eg alcohol) and then applying it to the adhering surface, and coating by volatilizing only the solvent, pressing, heating Then, a method of bonding and the like is used. In addition, many studies have been conducted in which a prepreg is prepared by uniformly impregnating carbon powder or the like with a polyimide powder suspended in a solvent, and using this prepreg to manufacture a composite, which is used as a structural base material. In the case of adhesion using a polyimide powder in this way, the conventional crystalline polyimide powder of the above formula (1) cannot be adhered unless its melting point is exceeded.

[0006]

An object of the present invention is to provide an amorphous polyimide powder having a repeating structural unit represented by the above formula (1). Also, the above formula
It is an object of the present invention to provide an amorphous polyimide powder which can be processed at a lower temperature than conventional ones, that is, at a melting point or less, in addition to the excellent heat resistance inherent to polyimide in (1). Further, it is to provide a heat-resistant adhesive and an adhesive method capable of adhering at a lower temperature than before, that is, at a lower temperature than the melting point, in addition to the excellent adhesiveness peculiar to the polyimide of the formula (1).

[0007]

Means for Solving the Problems The present inventors basically have a method capable of molding or bonding at a lower temperature while maintaining the high heat resistance of a polyimide having the basic structure of the above formula (1). , The amorphous polyimide in which the molecular end of the polymer is sealed with a dicarboxylic acid anhydride is excellent in moldability at a lower temperature, and is also found to have excellent adhesiveness at a lower temperature, The present invention has been completed.

That is, the present invention uses the formula (1)

[Chemical 14] Having a repeating structural unit represented by
The end of the polymer molecule is formula (2)

[Chemical 15] (In the formula, Z is a monocyclic aromatic group having 6 to 27 carbon atoms, a condensed polycyclic aromatic group, or a non-condensed polycyclic aromatic group in which the aromatic groups are directly or mutually linked by a bridging member. An amorphous polyimide powder which is encapsulated with a dicarboxylic acid anhydride represented by a divalent group selected from the group consisting of) and which has essentially no reactive group at the polymer molecular end and which has good moldability. Powder to formula (3)

[Chemical 16] And 3,3′-diaminobenzophenone represented by the formula (4)

[Chemical 17] 3,3 ', 4,4'-benzophenone tetracarboxylic acid dianhydride represented by the formula (2)

[Chemical 18] (In the formula, Z is a monocyclic aromatic group having 6 to 27 carbon atoms, a condensed polycyclic aromatic group, or a non-condensed polycyclic aromatic group in which aromatic groups are connected to each other directly or by a crosslinking member. A dicarboxylic acid anhydride represented by a divalent group selected from the group consisting of) is mixed in an organic solvent in the presence of an organic base and reacted at a temperature of 100 to 400 ° C. The obtained polymer is discharged into a poor solvent that is uniformly mixed with the organic solvent to produce the polymer.

In this method, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride of the formula (4) is used per mol of 3,3'-diaminobenzophenone of the formula (3). 0.8 to 1.0 mol and 0.001 to dicarboxylic acid anhydride represented by the formula (2)
React 1.0 mol. The organic solvent used is preferably a phenolic solvent. Further, the amount of organic base is 10 with respect to tetracarboxylic dianhydride.
The amount of the poor solvent is preferably 0.5 to 100 times the amount of the organic solvent which is the polymerization solvent. The polyimide powder of the present invention essentially has the formula (1)

[Chemical 19] Having a repeating structural unit represented by
This molecular end has the formula (2)

[Chemical 20] (In the formula, Z is as described above), which is an amorphous polyimide powder sealed with a dicarboxylic acid anhydride and further discharged into a poor solvent and precipitated. The amorphous polyimide powder of the present invention includes 3,3′-diaminobenzophenone of the above formula (3) and 3,3 ′, 4,4′-of the above formula (4).
Benzophenone tetracarboxylic dianhydride and the above formula
The dicarboxylic acid anhydride represented by (2) is mixed in an organic solvent in the presence of an organic base, and the mixture is heated at 100 to 400 ° C.
After the reaction is carried out at the above temperature, the obtained polymer can be produced by discharging it into a poor solvent which is uniformly mixed with the reaction solvent used.

The method for producing the amorphous polyimide powder of the present invention will be described below. In the polyimide powder of the present invention, the diamine compound as a raw material is the above 3,3′-
Although diaminobenzophenone is used, other diamines can be mixed and used within a range that does not impair the good physical properties of this polyimide.

Examples of diamines that can be mixed and used include 4,4'-diaminobenzophenone, 3,4'-diaminobenzophenone, m-phenylenediamine and o-.
Phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, 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-amino Phenyl) (4-aminophenyl) sulfone, bis (4-aminophenyl) sulfone, 3,
3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 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] diphenyl sulfone, bis [4- {4- (4-aminophenoxy) phenoxy} phenyl] sulfone, 1,4-bis [4-
Examples include (4-aminophenoxy) -α, α-dimethylbenzyl] benzene and 1,3-bis [4- (4-aminophenoxy) -α, α-dimethylbenzyl] benzene, which may be used alone or in combination of two kinds. The above is mixed and used.

As the tetracarboxylic dianhydride as another raw material, 3,3 ', 4,4'-benzophenone tetracarboxylic dianhydride of the formula (4) is used. In the method of the present invention, the amount of the diamine compound and the tetracarboxylic dianhydride used is a tetracarboxylic acid dianhydride 0.8 to 1.0 mol ratio per 1 mol of the diamine compound,
From the viewpoint that the obtained polyimide powder has a more excellent balance of thermal oxidation stability and molding processability, it is preferably 0.
90 to 0.99 molar ratio.

Further, the formula (2) used in the method of the present invention.
The dicarboxylic acid anhydride of is represented by the following formula in which Z has 6 to 27 carbon atoms and

[Chemical 21] A monocyclic aromatic group represented by

[Chemical formula 22] A condensed polycyclic aromatic group represented by or

[Chemical formula 23] (In the formula, X ₁ is a direct bond, -O-, -S-, -SO _2- , -CH _2- , -CO
-, -C (CH ₃ ) _2- , -C (CF ₃ ) _2- ,

[Chemical formula 24] And Y is a direct bond, -O-, -S-, -SO _2- , -CH _2- , -CO
_{-, - C (CH 3)} 2 -, - C (CF 3) 2 - a is) aromatic group is a non-fused polycyclic aromatic group connected to each other than a direct bond or a bridge member represented by ..

Specifically, phthalic anhydride, 2,3-benzophenone dicarboxylic acid anhydride, 3,4-benzophenone dicarboxylic acid anhydride, 2,3-dicarboxyphenyl phenyl ether anhydride, 3,4-dicarboxyl Phenyl phenyl ether anhydride, 2,3-biphenyl dicarboxylic acid anhydride, 3,4-biphenyl dicarboxylic acid anhydride, 2,3-dicarboxyphenyl phenyl sulfone anhydride, 3,4-dicarboxyphenyl phenyl sulfone anhydride, 2,3-dicarboxyphenyl
Phenyl sulfide anhydride, 3,4-dicarboxyphenyl phenyl sulfide anhydride, 1,2-naphthalene dicarboxylic acid anhydride, 2,3-naphthalene dicarboxylic acid anhydride, 1,2-anthracene dicarboxylic acid anhydride, 2,3 -Anthracene dicarboxylic acid anhydride, 1,9
-Anthracene dicarboxylic acid anhydride and the like may be mentioned, and these may be used alone or in admixture of two or more. In the method of the present invention, the amount of the dicarboxylic acid anhydride used is 0.001 to 1.0 mol per mol of 3,3′-diaminobenzophenone of the formula (3). 0.
When the amount is less than 001 mol, the viscosity is increased during high temperature molding, which causes deterioration of moldability. Further, if it exceeds 1.0 mol, the mechanical properties are deteriorated. The preferred usage is
It is a ratio of 0.01 to 0.5 mol.

As the polymerization method in the present invention, a known polyimide polymerization method can be applied, but a general-purpose organic solvent is used as a reaction solvent. For example, N, N'-diethylformamide, 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, 1,3
-Dioxane, 1,4-dioxane, pyridine, α-picoline, β-picoline, γ-picoline, dimethyl sulfoxide, dimethyl sulfone, tetramethylurea, hexaphosphorotriamide, diphenyl sulfone, diphenyl ether, benzene, toluene, xylene, Examples thereof include anisole and triethylamine. Particularly, it is a preferable method to carry out the reaction in a phenolic solvent. Particularly preferred phenolic organic solvents used in this reaction include, for example, phenol, o-cresol, m-cresol,
p-cresol, o-chlorophenol, p-chlorophenol, m-chlorophenol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol,
2,6-xylenol, 3,4-xylenol, 3,5
-Xylenol and the like. In addition, these organic solvents may be used alone or in combination of two or more kinds. The amount of the solvent used is 1 to 50 times, preferably 2 to 10 times the total amount of the polyimide starting materials used in the reaction. If the amount is less than 1 time, the stirring becomes difficult and the reaction cannot be sufficiently performed.

As the organic base used in the method of the present invention, any organic base effective for polyimide polymerization can be used. For example, pyridine, α-picoline, β-picoline, γ-picoline, trimethylamine, triethylamine and the like are preferable. The amount is 1 to 1000 mol% with respect to the tetracarboxylic dianhydride, but preferably 10 to 30
It is 0 mol%. In the method of the present invention, 3,3 'was added to the organic solvent.
-A method of adding and reacting diaminobenzophenone, 3,3 ', 4,4'-benzophenone tetracarboxylic acid dianhydride and dicarboxylic acid anhydride is (a) 3,3', 4,4'-benzophenone tetracarboxylic acid A method of reacting a carboxylic acid dianhydride with 3,3′-diaminobenzophenone and then adding a dicarboxylic acid anhydride to continue the reaction. (B) 3,3′-diaminobenzophenone, dicarboxylic acid anhydride is added and reacted, and then 3,3 ′, 4,4′-
A method of adding benzophenone tetracarboxylic acid dianhydride and continuing the reaction. (C) Any addition method such as a method of simultaneously adding 3,3 ′, 4,4′-benzophenone tetracarboxylic acid dianhydride, 3,3′-diaminobenzophenone and dicarboxylic acid anhydride to cause a reaction may be used. ..

The reaction produces a polyamic acid and imidizes it to obtain a polyimide. First, in the polyamic acid formation reaction, the reaction temperature is usually 250 ° C or lower, preferably 50 ° C or lower. The reaction pressure is not particularly limited and can be carried out at normal pressure. The reaction time varies depending on the type of solvent and the reaction temperature, and is usually 0.1 to 24 hours. Further, the obtained polyamic acid is heated to 100 to 400 ° C. for imidization, or an imidizing agent such as acetic anhydride is used. By chemically imidizing using, a polyimide having a repeating unit corresponding to a polyamic acid is obtained. Also,
3,3 ′, 4,4′-benzophenone tetracarboxylic acid dianhydride and 3,3′-diaminobenzophenone and dicarboxylic acid dianhydride are suspended or dissolved in an organic solvent and then heated to remove polyimide. It is also possible to obtain a polyimide by simultaneously producing a precursor polyamic acid and imidizing it.

To obtain the amorphous polyimide powder of the present invention, when the polyimide produced by the above-mentioned method is dissolved in the organic solvent used,
The reaction mixture containing the polyimide was added to a polymer weight of 5
Discharge or throw in ˜100 times the amount of poor solvent under high speed stirring. Further, in the polyimide produced by the above method, when the polyimide is not dissolved in the organic solvent used and is precipitated, the same or different organic solvent is further added to dilute, or the temperature at which it becomes a dissolved state After making it into a dissolved state by heating to a region, etc.,
Eject or throw in 1 to 500 times the amount of poor solvent under high speed stirring. Furthermore, if similarly precipitated, once the polyimide powder is isolated from the reaction mixture by a known method, the isolated polyimide is dissolved in an organic solvent in which the polyimide is soluble, and this solution is 1 to 1 parts by weight of the polyimide. Eject or pour into 500 times the amount of poor solvent with rapid stirring. Alternatively, in the reaction mixture obtained by the above reaction method, the solvent mixed in the reaction system other than polyimide, the catalyst, etc. are removed by heating or / and decompression to obtain the polyimide powder once isolated or obtained by the above method. The obtained powder is redissolved in an organic solvent similar to the above reaction solvent, and this solution is discharged or put into a poor solvent of 1 to 500 times the weight of the polymer under high speed stirring. Furthermore, the polyimide powder obtained by the known method or the method of the present invention is extruded, injected, and the molded article of the amorphous polyimide molded by various molding methods such as sintering may be crushed to obtain a polyimide powder. Absent. Also,
A molded product molded by the same method is dissolved in an organic solvent that dissolves the polyimide, and the polymer solution is discharged or put into a poor solvent whose amount is 1 to 500 times the polymer weight under high-speed stirring to obtain an amorphous polyimide powder. You can also get These methods are largely different from the conventional polyimide manufacturing methods, and the amorphous polyimide powder unique to the present application can be obtained by these methods.

In this precipitation method, examples of the solvent that can be used as the poor solvent include acetone, methyl ethyl ketone, methanol, ethanol, n-propanol,
i-propanol, pentane, hexane, heptane, octane, pentene, cyclohexane, cyclohexanol, 1,3-dioxane, 1,4-dioxane, benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, anisole , Acetophenone,
Pyridine, α-picoline, β-picoline, γ-picoline, diethyl ether, methyl acetate, acetaldehyde, acetonitrile, acrylonitrile, triethylamine, carbon tetrachloride, dichloromethane, chloroform,
Examples include 1,1,2-trichloroethane, 1,1,2,2-tetrachloroethane, chlorobenzene and the like. Preferred are acetone, methyl ethyl ketone, and toluene. Further, these precipitation solvents may be used as a mixture of two or more kinds in a range that does not impair the properties of the obtained polyimide powder. Furthermore, the temperature of the solution or reaction mixture containing polyimide at the time of discharging or charging is not particularly limited, but is preferably in the range of room temperature to 100 ° C. from the viewpoint of workability and stability.

The precipitation method is not particularly limited, and it can be precipitated by a known method.
The amorphous polyimide powder precipitated in the poor solvent can be separated by a conventional method to obtain the amorphous polyimide powder of the present invention. When this amorphous polyimide powder of the present invention is subjected to melt molding, other thermoplastic resin within a range that does not impair the object of the present invention, for example, polyethylene, polypropylene, polycarbonate, polyarylate, polyamide, polysulfone, polyether sulfone, Polyetherketone,
Polyphenylene sulfide, polyamide imide, polyether imide, modified polyphenylene oxide, polyimide other than the present invention and the like may be added in an appropriate amount according to the purpose.

Further, the following fillers used in ordinary resin compositions may be used to such an extent that the object of the invention is not impaired. That is, graphite, carborundum, silica powder, molybdenum disulfide, wear resistance improvers such as fluororesin, glass fiber, carbon fiber, boron fiber, silicon carbide fiber, carbon whiskers, asbestos, metal fibers, ceramic fibers and the like reinforcement Materials, flame retardants such as antimony trioxide, magnesium carbonate and calcium carbonate, 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, iron powder, zinc powder, aluminum powder,
Examples include thermoelectric conductivity improvers such as copper powder, glass beads, glass spheres, talc, diatomaceous earth, alumina, silasbaln, hydrated alumina, metal oxides, and colorants.

The amorphous polyimide powder of the present invention exhibits excellent adhesiveness as a heat resistant adhesive, especially at a low temperature of 300 ° C. or lower. The method of applying this amorphous polyimide powder as a heat-resistant adhesive is a thin layer on an adherend to which a suspension of this amorphous polyimide powder suspended in an easily volatile organic solvent is to be stuck. And then deposit the adherend in air for a required time of 10
Excessive solvent is removed by heating to about 0 to 300 ° C, then pressure bonding at 1 to 1000 kg / cm ² and pressure at 100 to 300 ° C, and curing at 100 to 300 ° C, the adherend Can be firmly adhered. Alternatively, the amorphous polyimide powder is inserted and adhered between the adherends, pressure-bonded at a pressure of 1 to 1000 kg / cm ² and a temperature of 100 to 300 ° C., and cured at a temperature of 100 to 300 ° C. The adhesive substance can be firmly adhered. Also,
When the heat-resistant adhesive is applied to the adherends to be bonded, good adhesive effect can be obtained by applying it to only one adherent or to both adherends respectively.

The surface of the adherend may be chemically or physically treated and then adhered. As the surface treatment method, chemical etching with acid or alkali,
Corona treatment, ultraviolet irradiation, radiation irradiation, sandblasting, heat treatment, plasma treatment, chemical treatment, homing treatment, plating treatment, oxide film treatment, degreasing treatment and the like are available.
When the heat-resistant adhesive of the present invention is used, it is possible to add another resin and bond it within a range that does not impair the characteristics of the heat-resistant adhesive of the present invention. Other resins to be added include nylons, polyacetals, polycarbonates, polyphenylene oxides, polyethylene terephthalates, polysulfones, polyether sulfones, polyarylates, polyamideimides, polyetherimides, polyetheretherketones, polyimides other than the present invention. , Fluororesin, polybismaleimide, epoxy resin and the like. One or more solid lubricants such as molybdenum disulfide, graphite, boron nitride, lead monoxide, and lead powder can be added to the heat-resistant adhesive of the present invention. Further, one or more reinforcing materials such as glass fiber, carbon fiber, aromatic polyamide fiber, potassium titanate fiber, glass beads and the like can be added. Furthermore, one or more ordinary additives such as antioxidants, heat stabilizers, ultraviolet absorbers, flame retardants, flame retardant aids, antistatic agents, and colorants may be added within a range that does not impair the object of the present invention. You can

[0024]

EXAMPLES Hereinafter, the present invention will be described with reference to Examples and Comparative Examples.
Further details will be described. The physical properties in Examples and Comparative Examples were measured by the following methods. Tg, Tc, Tm; (Shimadzu DT-40 series, DSC
-41M) Melting start temperature: Shimadzu Koka type flow tester CFT500
Measured with A at a load of 100 kg and a heating rate of 5 ° C / min. Adhesion test: Each polyimide powder was suspended in ethanol to form a paste, and then two cold-rolled steel sheets (JI
SG-3141, SPCC, SD, size 1.6x2
5 × 100 mm) and adhered with a hot press at 280 ° C. and 300 ° C. at 15 kg / cm ² . The method for measuring the tensile shear adhesive strength of the adhesive body was based on JIS K-6848.

Example 1 A container equipped with a stirrer, a reflux condenser, a water separator and a nitrogen inlet tube was provided with 12.72 of 3,3'-diaminobenzophenone.
g (0.06 mol), 3,3 ', 4,4'-benzophenone tetracarboxylic acid dianhydride 18.547 g (0.0
576 mol), 0.7104 g of phthalic anhydride (0.00
48 mol), γ-picoline 0.837 g (0.009 mol) and m-cresol 125.1 g were charged, and the mixture was heated to 150 ° C. with stirring under a nitrogen atmosphere.
During this period, about 2 cc of water was confirmed to be distilled. Furthermore, 15
The reaction was carried out at 0 ° C for 4 hours. Then cool to room temperature,
It was discharged into about 300 g of methyl ethyl ketone and filtered to obtain a polyimide powder. The polyimide powder was washed with about 300 g of methyl ethyl ketone and then dried in air at 50 ° C. for 12 hours and in nitrogen at 220 ° C. for 4 hours to obtain 29.16 g (yield 97.8%) of polyimide powder. The polyimide powder thus obtained had an inherent viscosity of 0.49 dl / g. The logarithmic viscosity is a value measured at 35 ° C. after 0.50 g of polyimide powder was dissolved by heating in 100 ml of p-chlorophenol / phenol (weight ratio 9/1) mixed solvent. The glass transition temperature of this polyimide powder is 240
And a 5% weight loss temperature in air was 550 ° C. The infrared absorption spectrum of this polyimide powder is shown in FIG. This spectrum diagram, the absorption near 1780 cm ^-1 and 1720 cm ^-1 imide characteristic absorption bands were remarkably observed.

The elemental analysis values of the obtained polyimide powder are as follows. C NH Calculated value (%) 72.29 5.62 2.81 Analytical value (%) 72.20 5.67 2.85 Furthermore, the X-ray diffraction pattern of the polyimide powder of this Example is shown in FIG. Show. The diffraction pattern shows that it is clearly amorphous. The melting start temperature of this polyimide powder was measured using a Koka type flow tester using a load of 100 kg and an orifice having a diameter of 0.1 cm and a length of 1 cm. The heating rate at this time is 5 ° C./min. The melting start temperature was 320 ° C. 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 is 35
The test was performed at 0 ° C. and a load of 100 kg. Results are shown in FIG. It can be seen that even if the residence time in the cylinder becomes long, the melt viscosity hardly changes, and the thermal oxidation stability is good. When an adhesion test was conducted using this polyimide powder, the tensile shear adhesive strength was 278 at a pressing temperature of 280 ° C.
kg / cm ² , 319 kg / cm at a press temperature of 300 ° C
^{Was 2} .

Comparative Example 1 A reactor similar to that used in Example 1 was charged with 12.72 g (0.016 mol) of 3,3'-diaminobenzophenone and 3,3'-diaminobenzophenone.
3 ', 4,4'-benzophenone tetracarboxylic dianhydride 18.547 g (0.0576 mol), phthalic anhydride 0.7104 g (0.0048 mol), γ-picoline 0.837 g (0.009 mol) , M-cresol 17
5.8 g was charged and the temperature was raised to 150 ° C. with stirring under a nitrogen atmosphere. During this period, about 2 cc of water was confirmed to be distilled. Further, the reaction was carried out at 150 ° C. for 4 hours.
Then, the mixture was cooled to 110 ° C., 116 g of toluene was added dropwise, and polyimide powder was deposited. The filtered polyimide powder was washed with about 150 g of toluene and then in air at 50 ° C.
Dried for 12 hours at 250 ° C. for 4 hours in nitrogen for 29.2.
8 g (yield 98.2%) of polyimide powder was obtained. The polyimide powder thus obtained had an inherent viscosity of 0.46 dl /
It was g. The glass transition temperature of this polyimide powder was 241 ° C, and the 5% weight loss temperature in air was 552 ° C. Furthermore, when the infrared absorption spectrum of this polyimide powder was measured, it was found to be an imide characteristic absorption band, 1780.
absorption in the vicinity of cm ^-1 and 1720cm ^-1 was observed significantly. The X-ray diffraction pattern of the polyimide powder of this comparative example is shown in FIG.
Shown in the figure. The diffraction pattern is clearly crystalline. Furthermore, the melting start temperature of this polyimide powder was 325 ° C. Further, when an adhesion test was conducted using this polyimide powder, the tensile shear adhesive strength was 0 at a pressing temperature of 280 ° C.
was 151 kg / cm ² in kg / cm ^2, 300 ℃.

Example 2 10 g of the polyimide powder obtained in Comparative Example 1 and 90 g of m-cresol were charged in the same reactor as in Example 1, and 15
The temperature was raised to 0 ° C. to dissolve it. Then, the mixture was cooled to room temperature, discharged into about 200 g of methyl ethyl ketone and filtered to obtain a polyimide powder. After washing this polyimide powder with 100 g of methyl ethyl ketone, it was heated at 50 ° C in air for 12
And dried in nitrogen at 220 ° C. for 4 hours.

The glass transition temperature of the polyimide powder obtained in this example was 240 ° C., and the X-ray diffraction pattern was amorphous. Further, the melting start temperature of this polyimide powder is 315 ° C., and the tensile shear adhesive strength is 280 kg / cm ² at a pressing temperature of 280 ° C. and 31 at 300 ° C.
It was 1 kg / cm ² .

Comparative Example 2 12.72 g (0.06 mol) of 3,3'-diaminobenzophenone, 3,3 ', was added to the same reactor as in Example 1.
4,4'-benzophenone tetracarboxylic acid dianhydride 1
8.547 g (0.0576 mol), phthalic anhydride 0.
7104 g (0.0048 mol), γ-picoline 5.5
8 g (0.06 mol) and 93.8 g of m-cresol were charged, and the mixture was heated to 150 ° C. with stirring under a nitrogen atmosphere. During this period, about 2 cc of water was confirmed to be distilled. Further, the reaction was carried out at 150 ° C. for 4 hours. Then 11
After cooling to 0 ° C., 116 g of toluene was added dropwise to deposit polyimide powder. The polyimide powder filtered out is about 15
After washing with 0 g of toluene, it was dried in air at 50 ° C. for 12 hours and in nitrogen at 250 ° C. for 4 hours to give 29.22 g.
(Yield 98.0%) was obtained. The polyimide powder thus obtained had an inherent viscosity of 0.45 dl / g. The glass transition temperature of this polyimide powder is 24
The temperature was 0 ° C., and the 5% weight loss temperature in air was 555 ° C. Further, the infrared absorption spectrum of this polyimide powder was measured to find that it was 178, which was an imide characteristic absorption band.
Absorption in the vicinity of 0cm ^-1 and 1720cm ^-1 was observed significantly. The X-ray diffraction pattern of the polyimide powder of this comparative example was clearly crystalline. Furthermore, the melting start temperature of this polyimide powder was 345 ° C., and the tensile shear adhesive strength was 0 kg / cm ² at a pressing temperature of 280 ° C. and 21 kg / cm ² at 300 ° C.

Example 3 10 g of the polyimide powder obtained in Comparative Example 2 and 90 g of m-cresol were charged in the same reactor as in Example 1, and 19
The temperature was raised to 0 ° C. to dissolve it. Then, the mixture was cooled to room temperature, discharged into about 200 g of methyl ethyl ketone and filtered to obtain a polyimide powder. After washing this polyimide powder with 100 g of methyl ethyl ketone, it is heated at 50 ° C. in air for 12 hours.
And dried in nitrogen at 220 ° C. for 4 hours. The glass transition temperature of the polyimide powder obtained in this example was 239 ° C., and the X-ray diffraction pattern was amorphous. Furthermore, the melting start temperature of this polyimide powder is 310 ° C., and the tensile shear adhesive strength is 2 at a pressing temperature of 280 ° C.
Was 307kg / cm ² at 62kg / cm ^2, 300 ℃.

Comparative Example 3 In the same manner as in Example 1, 21.2 g (0.1 mol) of 3,3 ',-diaminobenzophenone and N-methyl-2 were placed in the reactor.
-Pyrrolidone (209.7 g) was charged, and 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride (31.23 g (0.097 mol)) was charged in portions under a nitrogen atmosphere while paying attention to the temperature rise. did. Then, phthalic anhydride 2.
66 g (0.018 mol) was charged and stirred for 24 hours. Furthermore, acetic anhydride 40.8 g (0.4 mol) and γ-
After 0.93 g (0.01 mol) of picoline was added dropwise, the temperature was raised to about 70 ° C. to precipitate polyimide powder.
The filtered polyimide powder is methyl ethyl ketone 280 m.
l, washed in air at 50 ° C for 12 hours, nitrogen in 250 ° C
After drying for 4 hours, 46.9 g (yield 96.0%) of polyimide powder was obtained. The polyimide powder thus obtained had an inherent viscosity of 0.46 dl / g. The glass transition temperature of this polyimide powder was 238 ° C, and the 5% weight loss temperature in air was 553 ° C. Furthermore, when the infrared absorption spectrum of this polyimide powder was measured,
Imide characteristic absorption bands of 1780 cm ^-1 and 1720 cm
Absorption around ^-1 was noticeable. The X-ray diffraction pattern of the polyimide powder of this comparative example is shown in FIG. Furthermore, the melting start temperature of this polyimide powder is 320 ° C., and
Tensile shear adhesive strength is 28 kg / at press temperature of 280 ° C
cm ² and 153 kg / cm ² at 300 ° C.

Example 4 10 g of the polyimide powder obtained in Comparative Example 3 and 90 g of m-cresol were charged in a reactor similar to that of Example 1, and 150
The temperature was raised to 0 ° C. to dissolve it. Then, the mixture was cooled to room temperature, discharged into about 200 g of methyl ethyl ketone and filtered to obtain a polyimide powder. The polyimide powder was washed with 100 g of methyl ethyl ketone and then dried in air at 50 ° C. for 12 hours and in nitrogen at 220 ° C. for 4 hours. The glass transition temperature of the polyimide powder obtained in this example is 240 ° C.,
The X-ray diffraction pattern was amorphous. Furthermore, the melting start temperature of this polyimide powder is 315 ° C., and the tensile shear adhesive strength is 263 kg at a pressing temperature of 280 ° C.
/ Cm ² and 324 kg / cm ² at 300 ° C.

Comparative Example 4 A polyimide powder was obtained in exactly the same manner as in Example 1, but without using phthalic anhydride. This polyimide powder had a glass transition temperature of 241 ° C. and a constant viscosity of 0.52 dl / g.
The melt viscosity was measured by changing the residence time in the flow tester cylinder in the same manner as in Example 1, and as shown in FIG. 3, the melt viscosity increased as the residence time increased. It was inferior in thermal stability to the obtained polyimide.

[0035]

EFFECT OF THE INVENTION The polyimide powder obtained according to the present invention is superior in melt flow stability at low temperature side and has greatly improved moldability as compared with conventionally known polyimide, and further has relatively low temperature side. Since it has sufficient adhesive strength, it can be used as a molding process or an adhesive.

[Brief description of drawings]

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

2 is an X-ray diffraction pattern of the polyimide powder obtained in Example 1. FIG.

FIG. 3 To compare the molding stability of the polyimide powder obtained in Example 1 and the polyimide powder of Comparative Example 4,
Melt viscosity of each polyimide powder measured at a temperature of 350 ° C. and a load of 100 kg while changing the residence time in the cylinder of the flow tester.

FIG. 4 is an X-ray diffraction pattern of the polyimide powder obtained in Comparative Example 1.

5 is an X-ray diffraction pattern of the polyimide powder obtained in Comparative Example 5. FIG. In addition, in FIGS. 2, 4 and 5, the horizontal axis represents a value twice as large as an angle (referred to as α) formed by an incident ray and a reflected ray during X-ray irradiation, that is, 2α (referred to as a scattering angle). The vertical axis represents the number of X-ray absorptions per second, that is, C
OUNT / SEC. (It is called cps).

Claims (9)

[Claims] 1. Formula (1): Having a repeating structural unit represented by
The polymer molecule end is represented by the formula (2): (In the formula, Z is a monocyclic aromatic group having 6 to 27 carbon atoms, a condensed polycyclic aromatic group, or a non-condensed polycyclic aromatic group in which the aromatic groups are directly or mutually linked by a bridging member. An amorphous polyimide powder which is encapsulated with a dicarboxylic acid anhydride represented by a divalent group selected from the group consisting of) and which essentially does not contain a reactive group at the polymer molecular end and which has good moldability. 2. Formula (3): 3,3′-diaminobenzophenone represented by the formula (4): 3,3 ′, 4,4′-benzophenone tetracarboxylic acid dianhydride represented by the formula and a compound represented by the formula (2): (In the formula, Z is a monocyclic aromatic group having 6 to 27 carbon atoms, a condensed polycyclic aromatic group, or a non-condensed polycyclic aromatic group in which aromatic groups are connected to each other directly or by a crosslinking member. A dicarboxylic acid anhydride represented by a divalent group selected from the group consisting of the following) is reacted in an organic solvent, and then the obtained polymer is uniformly mixed with the organic solvent in a poor solvent. The method for producing an amorphous polyimide powder according to claim 1, which has a repeating structural unit represented by the formula (1), which is discharged. 3. Formula (1): Having a repeating structural unit represented by
The polymer molecule ends are represented by the formula (2): (In the formula, Z is a monocyclic aromatic group having 6 to 27 carbon atoms, a condensed polycyclic aromatic group, or a non-condensed polycyclic aromatic group in which aromatic groups are connected to each other directly or by a crosslinking member. In a organic solvent that dissolves this polyimide powder, which is encapsulated with a dicarboxylic acid anhydride represented by a divalent group selected from the group consisting of The amorphous polyimide powder according to claim 1, which has a repeating structural unit represented by the formula (1), wherein the amorphous polyimide powder is dissolved in a solvent and the polymer solution is discharged into a poor solvent that is uniformly mixed with the organic solvent. A method of manufacturing. 4. The amount of 3,3 ′, 4,4′-benzophenonetetracarboxylic acid dianhydride of the formula (4) is 0.8 to 1. per mol of 3,3′-diaminobenzophenone of the formula (3).
The method for producing an amorphous polyimide powder according to claim 2, wherein 0 mol and 0.001 to 1.0 mol of the dicarboxylic acid anhydride represented by the formula (2) are reacted. 5. The method for producing an amorphous polyimide powder according to claim 2, wherein the organic solvent is a phenolic solvent. 6. The amount of the organic base is 10 to 1000 mol% with respect to the tetracarboxylic dianhydride, and the amount of the poor solvent is 1 to 100 times the amount of the organic solvent as the polymerization solvent. The method for producing an amorphous polyimide powder according to claim 2. 7. Formula (1): Having a repeating structural unit represented by
The polymer molecule ends are represented by the formula (2): (In the formula, Z is a monocyclic aromatic group having 6 to 27 carbon atoms, a condensed polycyclic aromatic group, or a non-condensed polycyclic aromatic group in which the aromatic groups are directly or mutually linked by a bridging member. A heat-resistant adhesive which is encapsulated with a dicarboxylic acid anhydride represented by a divalent group selected from the group consisting of) and which essentially contains an amorphous polyimide powder containing no reactive group at the polymer molecular end. Agent. 8. The formula (1): Having a repeating structural unit represented by
The polymer molecule ends are represented by the formula (2): (In the formula, Z is a monocyclic aromatic group having 6 to 27 carbon atoms, a condensed polycyclic aromatic group, or a non-condensed polycyclic aromatic group in which the aromatic groups are directly or mutually linked by a bridging member. An amorphous polyimide powder which is capped with a dicarboxylic acid anhydride represented by a divalent group selected from the group consisting of) and which does not essentially contain a reactive group at the polymer molecular end, or this amorphous polyimide. Insert or apply a suspension of powder between the adherends and
A method of bonding by pressure bonding at 0 to 300 ° C. 9. The amorphous polyimide powder comprises 3,3′-diaminobenzophenone and 3,3 ′, 4,4′-benzophenone tetracarboxylic acid dianhydride and a compound represented by the formula (2): (In the formula, Z is a monocyclic aromatic group having 6 to 27 carbon atoms, a condensed polycyclic aromatic group, or a non-condensed polycyclic aromatic group in which aromatic groups are connected to each other directly or by a crosslinking member. A dicarboxylic acid anhydride represented by a divalent group selected from the group consisting of) is reacted in an organic solvent, and then the obtained polymer is uniformly mixed with the organic solvent in a poor solvent. The bonding method according to claim 8, which is an amorphous polyimide powder obtained by discharging.