JPH0723462B2 - Heat resistant adhesive - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heat-resistant adhesive, and particularly to an adhesive excellent in strong adhesive force and heat resistance.

[Prior Art] Heretofore, adhesives composed of various organic synthetic polymers have been known. Among them, as a material having excellent heat resistance, adhesives such as polybenzimidazole-based and polyimide-based adhesives have been developed. ing. In addition to the above-mentioned adhesives, fluorine-based resin, polyamide-imide, silicone, epoxy novolac, epoxy acrylic, nitrile rubber phenol or polyester adhesives have been developed, but these are also satisfactory in terms of heat resistance. Those having poor adhesive strength, and those having excellent adhesive strength, on the other hand, have poor heat resistance are not satisfactory.

[Problems to be solved by the invention]

An object of the present invention is to obtain a novel heat-resistant adhesive having heat resistance in which the adhesive force does not decrease during use and after use even when used at high temperature, and a stronger adhesive force.

[Means for solving problems]

The present inventors have conducted intensive studies to achieve the above-mentioned object, and completed the present invention.

That is, the heat-resistant adhesive of the present invention has the formula (I) (Where X is Represents Y, pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 2,2 ′, 3,3 ′
-Benzophenone tetracarboxylic dianhydride, 3,3 ', 4,
4'-biphenyltetracarboxylic dianhydride, 2,2 ', 3,
3'-biphenyltetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2
-Tetravalent derived from bis (2,3-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride or bis (3,4-dicarboxyphenyl) sulfone dianhydride Represents an aromatic group of R ₁ ,
R ₂ and R ₃ each represent a hydrogen atom or a methyl group. ) A heat-resistant adhesive comprising a polymer composed of repeating units represented by

The heat-resistant adhesive of the present invention is a polymer composed of repeating units represented by the above formula (I), that is, a polyamic acid and / or a polyimide having repeating units represented by the above formula (I).

The polymer which is the heat-resistant adhesive of the present invention has the formula (II) as the diamine component. (Wherein R ₁ , R ₂ and R ₃ each represent a hydrogen atom or a methyl group), that is, 2,2-bis [4-
(3-Aminophenoxy) phenyl] propane is used as a methyl-substituted product, and specifically, 2- [4-
(3-Aminophenoxy) phenyl] -2- [4- (3
-Aminophenoxy) -3-methylphenyl] propane, 2,2-bis [4- (3-aminophenoxy) -3-
Methylphenyl] propane, 2- [4- (3-aminophenoxy) phenyl] -2- [4- (3-aminophenoxy) -3,5-dimethylphenyl] propane, 2,2-bis [4- (3 -Aminophenoxy) -3,5-dimethylphenyl] propane, which is obtained by reacting this with one or more tetracarboxylic acid dianhydrides and / or further dehydration and cyclization thereof. The resulting polyimide.

It is not known at all to use a polymer obtained from an etherdiamine having an ether bond and an aromatic amino group in the same molecule and a tetracarboxylic dianhydride as an adhesive.

These polymers can be usually produced by reacting the above ether diamine with tetracarboxylic dianhydride in an organic solvent.

The tetracarboxylic dianhydride, for example, ethylenetetracarboxylic dianhydride, cyclopentanecarboxylic dianhydride, pyromellitic dianhydride, 3,3 ', 4,4'-benzophenone tetracarboxylic dianhydride, 2,2 ', 3,3'-benzophenone tetracarboxylic dianhydride, 3,3', 4,4 '
-Biphenyltetracarboxylic dianhydride, 2,2 ', 3,3'
-Biphenyltetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2
-Bis (2,3-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, 1,1- Bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, 2,3,6 , 7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride,
1,2,3,4-benzenetetracarboxylic dianhydride, 3,4,9,1
Examples thereof include 0-perylenetetracarboxylic dianhydride, 2,3,6,7-anthracenetetracarboxylic dianhydride, and 1,2,7,8-phenanthrenetetracarboxylic dianhydride.

In the present invention, the formula (III) (In the formula, Y is pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 2,2 ′, 3,3′-
Benzophenone tetracarboxylic dianhydride, 3,3 ', 4,
4'-biphenyltetracarboxylic dianhydride, 2,2 ', 3,
3'-biphenyltetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2
-Tetravalent derived from bis (2,3-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride or bis (3,4-dicarboxyphenyl) sulfone dianhydride Represents an aromatic group. ) Tetracarboxylic acid dianhydride is used.

These tetracarboxylic dianhydrides may be used alone or in admixture of two or more.

The polymer formation reaction is usually carried out in an organic solvent. As the organic solvent used in this reaction, for example, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethylmethoxyacetamide, N-methyl-2-pyrrolidone, 1, 3-dimethyl-
2-imidazolidinone, N-methylcaprolactam, 1,
2-dimethoxyethane, bis (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,
Examples thereof include dimethyl sulfone, tetramethyl urea, hexamethyl phosphoramide and the like. These organic solvents may be used alone or in combination of two or more.

The reaction temperature is usually 60 ° 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 ether diamine, tetracarboxylic dianhydride, solvent used and reaction temperature, and the reaction is carried out for a time sufficient to complete the production of polyamic acid. Usually 4 to 24 hours is sufficient.

By such a reaction, in the following formula (I), X is (In the formula, Y, R ₁ , R ₂ and R ₃ are the same as described above.) A polyamic acid having a repeating unit is obtained.

Further, the polyamic acid thus obtained is dehydrated by heating at 100 to 300 ° C. or chemically treated with a dehydrating agent such as acetic anhydride. X is (In the formula, Y, R ₁ , R ₂ and R ₃ are the same as above.) A corresponding polyimide having a repeating unit is obtained.

In particular, the thus obtained polyimide used in the method of the present invention has the property of being soluble in various solvents including aliphatic halogenated hydrocarbons, and therefore, for example, as an electric wire varnish and a coverlay. When used, or in the production of films or as adhesives, processability,
It has a great feature that it is easy to handle and work.

In the method of the present invention, when the polymer thus obtained is used as an adhesive, (1) mainly as an adhesive solution containing the above polyamic acid, and (2) mainly having the above polyimide. It is roughly divided into.

In the case of (1), the adhesive solution mainly containing the polyamic acid is a solution in which polyamic acid is dissolved in an organic solvent, and is obtained by reacting ether diamine and tetracarboxylic dianhydride in the organic solvent. It may be a reaction product liquid containing the obtained polyamic acid. It may also contain a polyamic acid as a main component and a polyimide which is a cyclized product of the polyamic acid. Therefore, the polyamic acid-containing adhesive solution may be a solution or suspension partially containing polyimide.

When using an adhesive containing such a polyamic acid, a thin layer of a polyamic acid adhesive is applied to the adherend to be laminated, and then the adherend is adhered in air for a required time of 220 Preheat to about ℃ to remove excess solvent, to convert the polyamic acid adhesive to a more stable polyimide, then press-bond at a pressure of 1-1000 kg / cm ² and a temperature of 50-400 ℃, 100-400 Curing at a temperature of ℃ makes it possible to firmly bond the adherend.

In the case of (2), the above-mentioned polyimide is, for example, a film-like substance obtained by heating the above-mentioned polyamic acid by heat dehydration or a chemical treatment with a dehydrating agent such as acetic anhydride, or a powder-like substantially polyimide itself. Further, a part of the above polyamic acid may be contained.

When using such a substantially polyimide, insert a film or powder between the adherends, 1-1000 kg / c
By pressure bonding at a pressure of m ² at a temperature of 50 to 400 ° C. and curing at a temperature of 100 to 400 ° C., the adhesive substance can be firmly bonded.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to Synthesis Examples and Examples.

Synthesis Example-1 2,2-bis [4- (3-aminophenoxy) -3-methylphenyl] propane used in the present invention was obtained as follows.

1,2-Bis (4-hydroxy-
3-methylphenyl) propane 64 g (0.25 mol), m-
Dinitrobenzene (100.9 g, 0.6 mol), potassium carbonate (82.8 g) and N, N-dimethylformamide (650 ml) were charged, and the mixture was reacted at 145 to 150 ° C for 8 hours. After completion of the reaction, cool down 3
Of 2,2-bis [3-methyl-4- (3
The tar of [nitrophenoxy) phenyl] propane was separated. This tar-like material was washed with water, then charged into a 1 glass reaction vessel, further activated carbon 12 g, ferric chloride.
Charge 1.2 g of hexahydrate and 630 ml of methyl cellosolve,
Stir under reflux for 30 minutes. Then, 50 g (1.0 mol) of hydrazine hydrate was added dropwise at 70-80 ° C over 2 hours, and the mixture was refluxed for 6 hours.
Stir the time. After the completion of the reaction, the catalyst was removed by cooling and filtering, the methyl cellosolve was distilled off, and then 500 ml of a 20% aqueous methanol solution and 62.5 g of concentrated hydrochloric acid were added and dissolved by heating.
When 60 g is added and cooled to 20 to 25 ° C, crystals precipitate. After filtering this off, 450 ml of a 20% aqueous methanol solution was added again to dissolve it by heating, 45 g of sodium chloride was added, and the mixture was stirred and cooled to 20 to 25 ° C. to precipitate crystals. This is separated by filtration, neutralized with aqueous ammonia in water, filtered and washed with water, the obtained crystals are heated and melted in toluene, and then the aqueous layer is separated. Then, n-heptane is added to precipitate crystals. The precipitated crystal was separated by filtration and dried to obtain a light brown crystal of 2,2-bis [4- (3-aminophenoxy) -3-methylphenyl] propane.

Yield 79.5g (72.6% yield), mp 146-148 ° C. The purity measured by high performance liquid chromatography was 99.6%.

IR (KBr cm ^-1 ): 1225 (ether bond) 3470 and 3390 (amino group) Synthesis example-2 2- [4- (3-aminophenoxy) phenyl] -2- [4- (3 used in the present invention -Aminophenoxy)
-3-Methylphenyl] propane was obtained as follows.

6-0.5 g (0.25 mol) of 2- (4-hydroxyphenyl) -2- (4-hydroxy-3-methylphenyl) propane and m-dinitrobenzene 100.9 in a glass reaction vessel.
g (0.6 mol), 82.8 g of potassium carbonate and 650 ml of N, N-dimethylformamide are charged and the reaction is carried out at 140 to 150 ° C for 12 hours. After completion of the reaction, the mixture was cooled and discharged into water 3 to give crude 2-
A tar-like product of (3-nitrophenoxy) phenyl] -2- (3-methyl-4- (3-nitrophenoxy) phenyl] propane was separated, washed with water, and then charged into one glass container. 12g activated carbon, ferric chloride
Add 1.2 g of hexahydrate and 600 ml of isopropyl alcohol and stir under reflux for 30 minutes. Next, 50 g (1.0 mol) of hydrazine hydrate was added dropwise at 70 to 80 ° C. over 2 hours, and the mixture was stirred under reflux for 6 hours. After cooling, the catalyst was filtered off and the methyl cellosolve was distilled off, then 10% aqueous methanol solution 500 ml
And 62.6 g of concentrated hydrochloric acid were added and dissolved by heating, and 50 g of salt was further added,
Crystals precipitate when cooled to 20-25 ° C with stirring.
After filtering this off, 450 ml of 10% aqueous methanol solution was added and dissolved by heating, 45 g of salt was added, and crystals were precipitated by cooling with stirring to 20-25 ° C. This is separated by filtration, neutralized with aqueous ammonia while stirring with toluene, heated and dissolved to separate the aqueous layer. Then, n-heptane is added to precipitate crystals. The precipitated crystals were separated by filtration, dried and then 2- [4-
(3-Aminophenoxy) phenyl] -2 [4- (3-
A slightly dried crystal of aminophenoxy) -3-methylphenyl] propane was obtained.

Yield 74.8 g (70.5% yield), mp 114-116 ° C. The purity measured by high performance liquid chromatography was 99.3%.

IR (KBr cm ^-1 ): 1225 (ether bond) 3440 and 3360 (amino group) Synthesis example-3 2,2-bis [4- (3-aminophenoxy) -3,5-dimethylphenyl used in the present invention ] Propane was obtained as follows.

1,2-Bis (4-hydroxy-
71 g (0.25 mol) of 3,5-dimethylphenyl) propane, m
-Dinitrobenzene 100.9g (0.6mol), potassium carbonate 8
Charge 2.8 g and 660 ml of N, N-dimethylformamide,
React at 140-150 ℃ for 15 hours. After completion of the reaction, the mixture was cooled to separate potassium sulfite by filtration, then the solvent of the filtrate was distilled off under reduced pressure, cooled to 90 ° C., 700 ml of water was charged, and the mixture was stirred for 1.0 hour. The crystals were separated by filtration and washed with water to obtain crude brown crystals of 2,2-bis [3.5-dimethyl-4- (3-nitrophenoxy) phenyl] propane. Then, the crystals were placed in a glass reaction vessel, 13 g of activated carbon, and ferric chloride hexahydrate 1.3 g.
Add g and 550 ml of methyl cellosolve, and stir under reflux for 30 minutes. Next, 50 g (1.0 mol) of hydrazine hydrate was added dropwise at 70 to 80 ° C over 2 hours, and the mixture was stirred at 70 to 80 ° C for 7 hours. After cooling, the catalyst was removed by filtration, the methyl cellosolve was distilled off, 250 g of 30% hydrochloric acid aqueous solution was added, then 120 ml of methanol was added, and 30 g of sodium chloride was further added, stirring for 20 to 20
Crystals precipitate when cooled to 25 ° C. After filtering this off, 560 ml of 50% aqueous methanol solution was added, 50 g of sodium chloride was further added, and the mixture was stirred and cooled to 20 to 25 ° C. to precipitate crystals. This was separated by filtration, neutralized with aqueous ammonia in water, filtered, washed with water, dried, and recrystallized from a mixed solvent of toluene and n-heptane to give 2,2-bis [4- (3-aminophenoxy).
A slightly brown crystal of -3,5-dimethylphenyl] propane was obtained.

Yield 88.5 g (76% yield), mp 112-114 ° C. The purity measured by high performance liquid chromatography was 99.5%.

Synthesis Example-4 2- [4- (3-aminophenoxy) phenyl] -2- [4- (3-aminophenoxy) used in the present invention
-3,5-Dimethylphenyl] propane was obtained as follows.

64 g (0.25 mol) of 2- (4-hydroxyphenyl) -2- (4-hydroxy-3,5-dimethylphenyl) propane and m-dinitrobenzene in a glass reaction vessel.
00.9 g (0.6 mol), 82.8 g of potassium carbonate and 630 ml of N, N-dimethylformamide are charged, and the mixture is reacted at 140 to 150 ° C for 14 hours. After the reaction was completed, the reaction mixture was cooled and discharged into 3000 ml of water.
-[4- (3-Nitrophenoxy) phenyl] -2-
A tar-like product of (3,5-dimethyl-4- (3-nitrophenoxy) phenyl] propane was separated.

This tar-like substance is washed with water, then charged into a glass container, 12 g of activated carbon, 1.2 g of ferric chloride hexahydrate and 630 ml of methyl cellosolve are added, and the mixture is stirred for 30 minutes under reflux. Next, 50 g (1.0 mol) of hydrazine hydrate was added dropwise at 70 to 80 ° C. over 2 hours, and the mixture was stirred under reflux for 8 hours. After cooling, the catalyst was removed by filtration and the methyl cellosolve was distilled off.
Add 500 ml of 25% aqueous methanol solution and 62.5 g of concentrated hydrochloric acid to dissolve by heating, add 50 g of common salt and stir at 20-25 ° C.
Crystals precipitate when cooled to. After separating this by filtration, 400 ml of 25% aqueous methanol solution is added and dissolved by heating, and 40 g of sodium chloride is added and the mixture is stirred and cooled to 20 to 25 ° C. to precipitate crystals.
This is separated by filtration, neutralized with ammonia water in water, filtered, and washed with water, and toluene is added to the obtained crystals to melt them by heating to separate an aqueous layer, and then n-heptane is added to precipitate crystals. The precipitated crystals were separated by filtration and dried to give 2- [4- (3-aminophenoxy) phenyl] -2- [4- (3-aminophenoxy) -3,5-dimethylphenyl] propane as a slightly brown crystal. It was

Yield 82.1 g (75% yield), mp 137-139 ° C. The purity measured by high performance liquid chromatography was 99.2%.

IR (KBr cm ^-1 ): 1230 (ether bond) 3450 and 3370 (amino group) Example-1 A container equipped with a stirrer, a reflux condenser and a nitrogen inlet tube was charged with 2,2-bis [4- (3 -Aminophenoxy) -3-
Methylphenyl] propane 21.9 g (0.05 mol) and N, N-
Charge 98 g of dimethylacetamide, and add 10.7 g (0.0493 mol) of pyromellitic anhydride in a nitrogen atmosphere at room temperature while carefully dividing the solution so that the temperature of the solution does not exceed 30 ° C. Stir it.

The polyamic acid thus obtained had a logarithmic viscosity at a concentration of 0.5% in a N, N-dimethylacetamide solvent at 35 ° C (the same applies hereinafter) was 2.56 dl / g.

Cold rolled steel sheet (JIS G3141, SPCC / SD, 25 × 100 × 1.6 mm, washed with this polyamic acid solution with trichlorethylene.
The same applies below. ) And heat-dried at 100 ° C for 1 hour and 220 ° C for 1 hour, and then cold-rolled steel sheets are overlaid at 320 ° C, 20kg /
Pressure was applied at cm ² for 5 minutes for pressure bonding. The thickness of the applied adhesive was 25 μm.

The tensile shear bond strength of this product is 340 kg / cm ² at room temperature.
It was 208 kg / cm ² when measured at a high temperature of 240 ° C. (The measuring method is based on JIS K6848 and 6850. The same applies to the following.) Also, after casting this polyamic acid solution on a glass plate, it was heated at 100 ° C, 200 ° C and 300 ° C for 1 hour each to obtain a polyimide film. The glass transition temperature of this polyimide film is 218 ° C (by TMA penetration method; the same applies below), and the 5% weight loss temperature in air is 480 ° C (DTA
-Measured by TG. The same applies below. )Met. This polyimide film was inserted between cold-rolled steel plates preheated to 130 ° C., and pressed at 320 ° C. for 20 minutes under a pressure of 20 kg / cm ² to be pressure-bonded. The tensile shear bond strength of this product at room temperature was 330 kg / cm ² , and when it was further measured at a high temperature of 240 ° C., it was 205
It was kg / cm ² .

Example-2 In a reaction vessel similar to that of Example-1, 2,2-bis [4- (3
-Aminophenoxy) -3-methylphenyl] propane
21.9 g (0.05 mol) and N, N-dimethylacetamide 113.
Charge 4g, cool to around 0 ℃, and under nitrogen atmosphere,
3 ', 4,4'-benzophenone tetracarboxylic acid dianhydride 1
2.88g (0.04mol) 4 while paying attention to the rise of solution temperature
After adding in portions and stirring for about 2 hours at around 0 ° C., the above solution was returned to room temperature, and further, under nitrogen atmosphere, 3,3 ′, 4,4 ′.
-Benzophenone tetracarboxylic acid dianhydride 3.02 g (0.0
(094 mol) was added, and the mixture was subsequently stirred under a nitrogen atmosphere for about 20 hours.

The polyamic acid thus obtained had an inherent viscosity of 1.20 dl / g.

A part of this polyamic acid solution was cast on a glass plate and then heated at 100 ° C., 200 ° C. and 300 ° C. for 1 hour to obtain a polyimide film. The glass transition temperature of this polyimide film was 194 ° C, and the 5% weight loss temperature in air was 482 ° C.

Furthermore, when a cold rolled steel sheet was pressure bonded under the same conditions as in Example-1 using this polyimide film, the tensile shear adhesive strength at room temperature was 300 kg / cm ² ,
It was 180 kg / cm ² when measured at a high temperature of 40 ° C.

Example-3 A container equipped with a stirrer, a reflux condenser and a nitrogen introducing tube was charged with 2- [4- (3-aminophenoxy) phenyl]-.
2- [4- (3-aminophenoxy) -3-methylphenyl] propane 21.2 g (0.05 mol) and N, N-dimethylacetamide 95.8 g were charged, cooled to around 0 ° C., and placed under a nitrogen atmosphere. , 8.72 g (0.04 mol) of pyromellitic dianhydride was added in 4 portions while paying attention to the rise of the solution temperature, and the mixture was stirred at about 0 ° C for about 2 hours, then returned to room temperature and further dried under a nitrogen atmosphere. Pyromellitic acid 2.02g (0.0093
Mol) and subsequently stirred under a nitrogen atmosphere for about 20 hours.

The polyamic acid thus obtained had an inherent viscosity of 2.10 dl / g.

The above polyamic acid solution was applied to a cold-rolled steel sheet that had been washed with trichlorethylene, dried by heating at 100 ° C for 1 hour and 220 ° C for 1 hour, and then the cold-rolled steel sheet was overlaid at 320 ° C, 20k.
Pressure was applied at g / cm ² for 5 minutes for pressure bonding.

The thickness of the applied adhesive was 24 μm.

The tensile shear bond strength of this product is 310 kg / cm ² at room temperature, and it is 215 kg / cm ² when measured at a high temperature of 240 ° C.
Met.

A part of this polyamic acid solution was taken, cast on a glass plate and then heated at 100 ° C, 200 ° C and 300 ° C for 1 hour to obtain a polyimide film. The glass transition temperature of this polyimide film was 229 ° C, and the 5% weight loss temperature in air was 475 ° C.

This polyimide film was inserted between cold-rolled steel plates preheated to 13 ° C., and pressure-bonded at 320 ° C. and 20 kg / cm ² for 5 minutes. The tensile shear bond strength of this product at room temperature is 300k.
It was g / cm ² , and when it was further measured at a high temperature of 240 ° C., it was 210 kg / cm ² .

Example-4 In a reaction vessel similar to that in Example-1, 2 [4- (3-aminophenoxy) phenyl] -2- [4- (3-aminophenoxy) -3-methylphenyl] propane 21.2 g (0.05
Mol) and 111.3 g of N, N-dimethylacetamide are charged, and 15.9 g (0.0494 mol) of 3,3 ′, 4,4′-benzophenonetetracarboxylic acid dianhydride at room temperature under a nitrogen atmosphere at a solution temperature of The mixture was added in portions taking care not to exceed 30 ° C, and the mixture was stirred at room temperature for about 20 hours.

The polyamic acid thus obtained had an inherent viscosity of 1.95 dl / g.

After casting this polyamic acid solution on a glass plate,
By heating at 100 ° C., 200 ° C. and 300 ° C. for 1 hour each, a pale yellow transparent polyimide film was obtained. The glass transition temperature of this polyimide film was 209 ° C, and the 5% weight loss temperature in air was 485 ° C.

When a cold rolled steel sheet was pressure-bonded using this film under the same conditions as in Example-1, the tensile shear adhesive strength was 28 at room temperature.
It was 0 kg / cm ² , and when it was further measured at a high temperature of 240 ° C., it was 195 kg / cm ² .

Examples-5 to 8 Various diamines were used in place of 2,2-bis [4- (3-aminophenoxy) -3-methylphenyl] propane in Example-1, and the amount and aroma of N, N-dimethylacetamide were used. Changing the type and amount of group tetracarboxylic dianhydride,
Otherwise in the same manner as in Example-1, a polyamic acid and a polyimide film were obtained.

The results are shown in Table-1.

The results of Examples-1 to 4 are also shown in Table-1.

Example-9 40.9 g of the polyamic acid solution obtained in Example-5 was charged into a vessel equipped with a stirrer, a reflux condenser and a nitrogen introducing tube, and the temperature was raised to 70 ° C, and then 6.15 g of acetic anhydride ( 0.06 mol)
Then, 2.13 g (0.02 mol) of triethylamine was added dropwise, and the mixture was further stirred for 2 hours. The resulting solution is discharged into 100 g of water,
Wash with methanol, dry under reduced pressure at 150 ℃ for 8 hours, 9.8g
Of pale yellow powder was obtained.

The glass transition temperature of this powder measured by DSC was 249 ° C, and the 5% weight loss temperature in air was 460 ° C. The infrared absorption spectrum of the obtained powder is shown in FIG.

In this spectrum, the characteristic absorption band of imide is 1720 cm.
Absorption in the vicinity of ^-1 and around 1780cm ^-1 was observed significantly.

The polyimide powder obtained in this example is dichloromethane, 1,2-dichloroethane, 1,1,2-trichloroethane,
Aliphatic halogenated hydrocarbons such as 1,1,2,2-tetrachloroethane, chloroform, ethyl bromide, tetrabromoethane and N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N, N-dimethylformamide, 1,3
20% by weight or more was soluble in an organic solvent such as dimethyl-2-imidazolidine at room temperature.

The polyimide powder obtained in this example was washed with trichlene and inserted between cold-rolled steel sheets preheated to 130 ° C., 300
Pressure was applied at 20 ° C. and 20 kg / cm ² for 5 minutes for pressure bonding.

The tensile shear bond strength of this product at room temperature was 320 kg / cm ² , and when it was further measured at a high temperature of 240 ° C., it was 208
It was kg / cm ² .

〔The invention's effect〕

The present invention provides an adhesive that exhibits a strong adhesive force without lowering heat resistance and can maintain a high adhesive force even at high temperatures.

[Brief description of drawings]

FIG. 1 is an example of an infrared absorption spectrum diagram of the polyimide powder of the present invention.

Claims (1)

[Claims] 1. A formula (I) (Where X is Represents Y, pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 2,2 ′, 3,3 ′
-Benzophenone tetracarboxylic dianhydride, 3,3 ', 4,
4'-biphenyltetracarboxylic dianhydride, 2,2 ', 3,
3'-biphenyltetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2
-Tetravalent derived from bis (2,3-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride or bis (3,4-dicarboxyphenyl) sulfone dianhydride Represents an aromatic group of R ₁ ,
R ₂ and R ₃ each represent a hydrogen atom or a methyl group. )
A heat-resistant adhesive comprising a polymer having a repeating unit represented by: