JPS61176629A - Production of heat-resistant resin - Google Patents

Abstract

PURPOSE:To obtain a polyimide resin, having balanced heat-resistance, flexibility and colorlessness, and high light transmittance and toughness, by using a specific tetracarboxylic acid dianhydride and a specific diamine as essential components. CONSTITUTION:The objective polyimide resin is derived from 3,3',4,4'- benzophenonetetracarboxylic acid dianhydride and a diamine component consisting of 2,8-diaminodiphenylene oxide and 3,3'-diaminodiphenylsulfone. The tetracarboxylic acid dianhydride is the one containing >=20(mol)% 3,3',4,4'- benzophenonetetracarboxylic acid dianhydride and the diamine component contains 0.5-50% 2,8-diaminodiphenylene oxide and >=20% 3,3'- diaminodiphenylsulfone.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a strong heat-resistant resin having excellent light transmittance and having a hetero imide ring and a furan ring in the polymer main chain. It is. The purpose of this is to ensure that the cured resin that has been cured through the ring-closing process has the heat resistance, abrasion resistance, chemical resistance, electrical insulation, film-forming properties, flexibility, and mechanical properties of a polyimide resin. It provides heat-resistant resins with excellent properties and useful as materials for electronic devices, electrical insulating materials, coatings, adhesives, paints, molded products, laminates, fibers, and film materials, among others, especially for electronic devices. K provides heat-resistant resins useful as alignment films for liquid crystal display devices.

[Prior art]

Conventionally, polymers having heterocycles such as imide, imidazole, thiazole, oxazole, oxadiazole, triazole, quinoxaline, thiadiazole, oxazinone ζ quinazoline, imidazopyrrolone, isoindoroquinazolone, etc. in the polymer main chain have good heat resistance. It is well known that it is superior. However, these known polymers have rigid polymer main chains, and when formed into films, films, or coatings, they have poor flexibility, flexibility, and elongation. Therefore, for example, when used as an alignment film for liquid crystal,
It cannot withstand rubbing work and cannot fully align the liquid crystal, making it unable to function as a display element. Furthermore, when these polymers are heated during curing, they become significantly colored, becoming brown or blackish brown.

Therefore, when used as an alignment film for a liquid crystal, for example, the liquid crystal display element becomes brownish, the visual field becomes dark, the contrast decreases, and it no longer functions as a display element. From this point of view, various studies have been made in the past in order to achieve a balance between heat resistance, flexibility, and light color property, but it has generally been the case that when one is improved, the other becomes worse.

[Purpose of the invention]

As a result of studies aimed at overcoming such drawbacks, the present invention has developed 2,8-diaminodiphenylene oxide and 3,3'-diaminodiphenylsulfone as a diamine component, and a tetracarboxylic acid cyanhydride component. 3#3
It has been discovered that by using '$4.4'-benzophenonetetracarboxylic dianhydride as an essential component, a heat-resistant resin with a good balance of heat resistance, flexibility, and light color can be obtained. This has led to the completion of the present invention.

[Structure of the invention]

In the present invention, when forming an imide ring by reacting a diamine and a tetracarboxylic dianhydride, 2,8-diaminodiphenylene oxide and 3.3
'-Diamino diphenyl sulfone and 3°3'*4*4'-benzophenone tetracarboxylic dianhydride as an essential component. It's a method.

Among the diamines used in the present invention, essential components are 2°8-diaminodiphenylene oxide and 3,3'-diaminodiphenylsulfone. One way to make 2,8-diaminodiphenylene oxide is shown in the following t-reaction formula.

Diphenylene oxide 2,8-dibromodiphenylene oxide 2,8-diaminodiphenylene oxide Reference: University of Fukui Faculty of Engineering Research Report 16 (2) 238
('68) Of course, diamines other than those mentioned above can also be used. For example, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, benzidi',
4+4'') 7 minodiphenylsulfi)', 414
'-Diamino diphenyl sulfone, 4,4'-diaminodiphenyl ether, 2,6-diamitupyridine, bis(4-aminophenyl)phosphine oxyto, bis(4
-aminophenyl)-N-methylamine, 1,5-diaminonaphthalene, 3,3'-dimethyl-4゜4'-diaminobiphenyl, 3,3'-dimethoxybenzidine, 2
, 4-bis(β-amino-t-butyl)toluene, bis(p-β-amino-t-)f-ruphenyl)ether, p
-bis(2methyl-4-amitintyl)benzene, p
-Bis(l,1-dimethyl-5-aminopentyl)benzene, m-xylylenediamine, p-xylylenediamine, bis(p-aminocyclohexyl)methane, ethylenediamine, propylenediamine, hexamethylenediamine, hexamethylenediamine , octamethylene diamine, nonamethylene diamine, decamethylene diamine,
3-methylhbutamethylenediamine, 4,4-dimethylhbutamethylenediamine, 2゜11-diaminodecane,
1,2-bis(3-aminoprodoxy)ethane, 2,2
-dimethylpropylenediamine, 3-methoxyhexamethylenediamine, 2.5-dimethylhexamethylenediamine, 2.5-dimethylnonamethylenediamine, 1,4
-diaminocyclohexane, 2,12-diaminooctadecane, 2,5-diamino-1,3,4-oxadiazole, and the like.

Furthermore, among the tetracarboxylic dianhydrides used in the present invention,
The essential component is 313',4,4'-benzophenonetetracarboxylic dianhydride. However, other tetracarboxylic dianhydrides can of course also be used. For example, pyromellitic dianhydride, 2゜316, 7-7talentetracarboxylic dianhydride, 3,3', 4.4'-
Diphenyltetracarboxylic dianhydride, 1.2, 5.6
-Naphthalenetetracarboxylic dianhydride, 2,2'3
．． 3'-diphenyltetracarboxylic dianhydride, 2.2
-Bis(3,4-dicarboxydiphenyl)pronozone dianhydride, 3,4,9.10-perylenetetracarboxylic dianhydride, bis(3,4-dicarboxydiphenyl)
Ether dianhydride, ethylenetetracarboxylic dianhydride, naphthalene-1=2-4*5-tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, 4,8- Dimethyl-1,2゜3= L 6t
7-hexahydronaphthalene-1,2t5,6-tetracarboxylic dianhydride, 2.6-dichloronaphthalene-1.4,5.8-tetracarboxylic dianhydride, 2.7-
cyclonaphthalene-114.5.8-tetracarboxylic dianhydride, 2,3,417-titrachloronaphthalene-1.4.5.8-tetracarboxylic dianhydride, phenanthrene-1,2,9, 10-tetracarboxylic dianhydride, cycloadan-1.2.3.4-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride, pyrazine 2.3.5 .6-tetracarboxylic dianhydride, 2,2-bis(2,5-dicarboxyphenyl)furonozone dianhydride, 1,1-bis(2,3
-dicarboxyphenyl)ethane dianhydride, 1.1-bis(L4-dicarboxyphenyl)ethane dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride,
Bis(3,4-dicarboxyphenyl)sulfone dianhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, 1,2.3.4-butanetetracarboxylic dianhydride, thiophene-2 , 3,4,5=tetracarboxylic dianhydride, and the like. The amount of 2,8-diaminodiphenylene oxide, which is an essential component, is preferably 0.5 to 50 mol. If it is less than 0.5 mole, the effect of improving heat resistance strength is small, and if it is more than 50 mole, the molecular weight will not increase, probably due to steric hindrance of the molecular structure. In addition, the amount of 3.3'-diaminodiphenylsulfont 3.3', 4.4'-benzophenone tetracarboxylic dianhydride used was 20
It is preferable that the amount is more than 100%, and if it is less than this, the effect of improving coloration is small.

In the present invention, the reaction between diamines and tetracarboxylic dianhydrides is preferably carried out in equimolar amounts as much as possible;
The degree of polymerization also increases. If the amount of either raw material increases by 5% or more, the degree of polymerization will drop significantly and a low molecular weight product with poor film-forming properties will be produced, so care must be taken. Usually, it is common practice to use 1 to 3 more of one raw material in order to improve workability and processability.

The solvent of the reaction system in the present invention is an organic polar solvent whose functional group has a dipole moment that does not react with the tetracarboxylic dianhydride or diamines.

In addition to being inert to the system and being a solvent for the product, the organic polar solvent must be a solvent for at least one, and preferably both, of the reaction components.

Typical solvents of this type include N,N-dimethylformamide, N,N-dimethylacetamide, N,
N-diethylformamide, N,N-diethylacetamide, N,N-dimethylmethoxyacetamide, dimethylsulfoxide, hexamethylphosphoamide, N-methyl-2-pyrrolidone, pyridine, dimethylsulfone,
Tetramethylene sulfone, dimethyltetramethylene sulfone, etc. These solvents may be used alone or in combination.

Other non-solvents that can be used in combination as solvents include benzene, benzonitrile, dioxane, phthyrolactone, xylene, toluene, and cyclohexane.
It is used as a dispersion medium for raw materials, a reaction control agent, a volatilization control agent for solvents from products, a film smoothing agent, etc.

It is generally preferred that the present invention be carried out under anhydrous conditions.

This is because the tetracarboxylic dianhydride may be ring-opened by water, inactivating it, and stopping the reaction.

Therefore, it is necessary to remove both the moisture in the raw materials and the moisture in the solvent.

However, water is sometimes intentionally added to adjust the progress of the reaction and control the degree of resin polymerization.

Further, the present invention is preferably carried out in an inert gas atmosphere.

This is to prevent oxidation of diamines.

Dry nitrogen gas is generally used as the inert gas.

The reaction in the present invention can be carried out in various ways, including first-order.

(1) Preparation of diamines and tetracarboxylic dianhydride
This method is relatively advantageous in exothermic reactions such as & + fuimide resins.

(2) On the other hand, there is also a method of adding a solvent to a mixture of monocyanes and tetracarboxylic dianhydride while stirring.

(3) A commonly used method is to dissolve only diamines in a solvent and add tetracarboxylic dianhydride to this in a proportion that allows control of the reaction rate.

(4) It is also possible to dissolve diamines and tetracarboxylic dianhydride separately in a solvent and then slowly add the two solutions in a reactor.

(5) Furthermore, it is also possible to prepare in advance a polyamic acid product containing an excess of diamines and a polyamic acid product containing an excess of tetracarboxylic dianhydride, and then further react them in a reactor.

(6) Among the diamines, there is also a method in which a portion of the diamine compound and tetracarboxylic dianhydride are first reacted, and then the remaining diamine compound is reacted, or the reverse method.

(7) In addition, one in which a part of the diamine compound among the diamines is reacted with tetracarboxylic dianhydride, and one in which the remaining diamine compound and tetracarboxylic dianhydride are reacted, Another option is to mix it before use.

The reaction temperature is preferably 0 to 100°C. If the temperature is below 0°C, the reaction rate will be slow; if the temperature is above 100°C, the produced polyamic acid will gradually start the ring-closing reaction.
``Normally, the reaction is carried out at around 20°C. ,j? The degree of polymerization of IJ amic acid can be controlled in a planned manner.

To control the degree of polymerization, monophthalic anhydride and
It is also possible to end-block with aniline, or add water to open one of the acid anhydride groups and inactivate it.

Manufactured by the method of the present invention. When using the t' +7 amic acid product, various silane coupling agents, borane coupling agents, titanate coupling agents, aluminum coupling agents and other chelate adhesive/adhesion improvers, various solvents, 70-agents may be added, and in addition to these, conventional acid curing agents,
Amine curing agent, iriamide curing agent and imidazole, 3
Small amounts of hardening accelerators such as grade amines may also be added, as well as flexibility agents and viscosity modifiers such as rubber, monosulfides, -lyesters, low-molecular edoxys, talc, clay, mica, feldspar powder, quartz. Small amounts of powder, fillers such as magnesium oxide, colorants such as carbon black and 7-tawacyanine blue, flame retardants such as tetrabromophenylmethane and tributyl phosphate, and flame retardant aids such as antimony trioxide and barium metaborate. These additions open up many uses.

The monoreamic acid product produced by the method of the present invention is diimidized and cured by heating or by using a dehydrating agent. The heating temperature for the former heating dehydration treatment is usually 50°C or higher, especially 15°C.
The temperature range is preferably 0°C or higher and 200 to 400°C. In this case, air may be used as the atmosphere, but non-oxidizing conditions such as reduced pressure or inert gas are often preferable. As the latter dehydrating agent, carboxylic anhydrides such as acetic anhydride, propionic anhydride, and benzoic anhydride are often used, but these are most effective when used in the presence of a basic substance such as pyridine or quinoline. In addition, solid dehydrating agents such as zeolite-based moles, silica gel, activated alumina, etc. are more effective when used after being slightly heated.

〔Effect of the invention〕

A polymer prepared according to the method of the present invention using 2,8-diaminodiphenylene oxide, 3,3'-diaminodiphenylsulfone and 3=3',4t4'-benzophenonetetracarboxylic dianhydride as essential components. is an excellent heat-resistant resin with a good balance of heat resistance, flexibility, and light color.

That is, the polymer synthesized by the method of the present invention has a 2.8-
Due to the use of diaminodiphenylene oxide, it has a large number of aromatic rings and heterocycles in its molecular structure) and has excellent heat resistance. In addition, the main chain has a spiral shape, which is thought to provide excellent flexibility due to a spring-like effect.

Furthermore, 3.3'-diaminodiphenylsulfont, 3.3
'.

4. A heat-resistant resin with less coloring can be obtained, probably because the main chain cannot form a conjugated structure by introducing the 4'-benzophenonetetracarboxylic dianhydride.

Specifically, the present invention is used as a coating film for protecting the surfaces of various electronic equipment, and as a heat-resistant insulating film for forming multilayer wiring thereon.

For example, semiconductors, transistors, and linear ICs.

High Prix) IC, light emitting diode, LSI, ultra-L
This is a wiring structure for electronic circuits such as SI.

Next, since the heat-resistant resin of the present invention is light in color, it can also be used as an alignment film for liquid crystal display devices.

That is, the polymer solution of the present invention is applied to a glass substrate or a plastic film substrate on which a transparent conductive film containing tin oxide or indium oxide as a main component is formed by a dipping method, a spin coating method, a spray method, a printing method, etc. After heating and curing,
Rubbing treatment. The rubbing method can be performed using gauze, puff polishing, or other conventional means. Liquid crystals that can be used in combination with the alignment film of the present invention include nematic liquid crystals such as Schiff base liquid crystals, phenylcyclohexane type liquid crystals, azoxy type liquid crystals, azo type liquid crystals, piphenyl type liquid crystals, ester type liquid crystals, and phenyl-pyrimidine type liquid crystals; Examples include cholesteric liquid crystals in which optically active compounds such as optically active substances, cholesterol compounds, piphenyl derivatives having optically active substituents, and phenylbenzoate are added to nematic liquid crystals. Other high-temperature coaching varnishes are used as electric wire coatings, magnet wires, dip coatings for various electrical parts, and insulation coatings for metal parts. /
Used for fiber impregnation, radar domes, printed circuit boards,
Used in radioactive waste storage containers, turbine blades, spacecraft and other structural components that require high-temperature performance and excellent electrical properties.
It is also used as an interior material for waveguides in convenience stores, atomic equipment, and X-ray equipment to prevent microwaves and radiation.

It is also used as a molding material by adding graphite powder, graphite fiber, molybdenum disulfide, and tetrafluoroethylene to create self-lubricating sliding surfaces, which are used for piston rings, valve seats, bearings, seals, etc. Also, by adding glass fiber, graphite fiber and poron fiber,
Jet engine parts and high-strength structural molded parts are made here.

It is also used as a high-temperature adhesive for bonding electrical circuit parts and structural parts of spacecraft.

〔Example〕

The present invention will be explained below with reference to Examples.

Example 1 19.82 of purified anhydrous 2,8-diaminodiphenylene oxide was placed in a four-neck Seno Z rubble flask equipped with a thermometer, a stirrer, a raw material inlet, and a dry nitrogen gas inlet.
3f (10 mol S>) and 223.470 ? (90 mol qk) of 3,3'-diaminodiphenylsulfone were added to 95% by weight of anhydrous N-methyl-2-pyrrolidone and 5% by weight of toluene. The mixed solvent was added in an amount sufficient to make the solid content of the total raw materials 15% by weight and dissolved.Dry nitrogen gas was used during the preparation stage of the reaction and throughout the entire process up to product removal. I left it running.

Then purified anhydrous 3.3',4,4'-benzophenonetetracarboxylic dianhydride 32Z23 f (10
0 mol. The internal temperature of the addition diameter was set at 20° C., and the reaction was completed by stirring for 10 hours.

The obtained product was a transparent yellow and extremely viscous polyamic acid solution, and the intrinsic viscosity of the 0.5% by weight solution of N-methyl-2-pyrrolidone was 0.81 (30°C).

Next, a 5% by weight solution of this boriaelectric acid in N-dimethylacetamide was dropped onto a glass plate and spun at 40 Orpm/min for 10 seconds and then at 2000 rpm/min for 20 seconds using a spinner. ,
Applied evenly. Under reduced pressure, 80°C, 150°C,
The mixture was sequentially heated at 250° C. and 350° C. for 30 minutes each to cause dehydration and ring closure, thereby obtaining a pale yellow transparent and tough polyimide resin film with a thickness of 1 μm. Looking at the infrared absorption spectrum of this film, it is 1780 cys-” and 730 as-
“Strong absorption based on the K imide ring and 1200CIK-1
A strong absorption based on the furan ring was observed.

This film has extremely excellent heat resistance, and the thermal decomposition initiation temperature in air was 505°C at a heating rate of 5°C/min, as measured using an indicative thermobalance analyzer. The film strength is also high, with a tensile strength of 15 kg / 200℃ hot.
It was excellent. Further, the film had excellent light color property, and the light transmittance was 91% at 400 nm.

Example 2 Using the same apparatus and method as in Example 1, 39.646 f (20 mol L) of 2,8-diaminodiphenylene oxide
II) 3#3'-diaminodiphenylsulfone 17
3.810 f (70 mol qb) and 20.024 f (10 mol qb) of 4,4'-diaminodiphenyl ether were combined with 161.0 f (10 mol qb) of 3,3',4,4'-hensiphenonetetracarboxylic dianhydride. 115S' (50%
Le*),! :Pirome! J 7 ) [Dianhydride 109.
060 f <50-E:%).

The obtained product was a transparent yellow and extremely viscous iliamic acid solution with an intrinsic viscosity of 0.90. In addition, the obtained film is pale yellow and transparent and has high toughness, with a thermal decomposition initiation temperature of 520°C and a hot tensile strength of 16 kg/w.
The n1 light transmittance was excellent at 88 inches.

Comparative Example 1 3,3'-diaminodiphenylsulfone 248.30 f (100 mol e
s) was reacted with 322.23 t (10 mol l) of 3.3', 4+ 4'-benzophenonetetracarboxylic dianhydride.

The obtained film was pale yellow and transparent, but its thermal decomposition initiation temperature was only 305°C and its tensile strength was 4-/-, meaning it could not withstand rubbing work at all.

Comparative Example 2 Using the same apparatus and method as in Example 1, 99.115 f (50 mol) of 2,8-diaminodiphenylene oxide and 100.12 mol of 4,4'-diaminodiphenyl ether were prepared.
0 f (50 mol %) and pyromellitic dianhydride 21 & 120 f (100 mol %) were reacted.

Although the obtained film was heat resistant and tough, it had a light transmittance of only 55SL and could not be used as a liquid crystal aligning film at all.

Claims (4)

[Claims] (1) 3,3',4,4'-benzophenone tetracarboxylic dianhydride is used as the tetracarboxylic dianhydride component of the polyimide resin consisting of tetracarboxylic dianhydride and diamine, and 2 , 8-diaminodiphenylene oxide and 3,3'-diaminodiphenylsulfone as essential components. (2) Claim 1, characterized in that it contains 20 mol% or more of 3,3',4,4'-benzophenone tetracarboxylic dianhydride as a tetracarboxylic dianhydride component. A method for producing the heat-resistant resin described above. (3) The method for producing a heat-resistant resin according to claim 1, which contains 0.5 to 50 mol% of 2,8-diaminodiphenylene oxide as a diamine component. (4) The method for producing a heat-resistant resin according to claim 1, which contains 20 mol% or more of 3,3'-diaminodiphenylsulfone as a diamine component.