JPS61176631A - Production of heat-resistant resin - Google Patents

Abstract

PURPOSE:To obtain a polyimide resin, having balanced heat-resistance, flexibility, colorlessness and adhesivity, 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 a tetracarboxylic acid dianhydride component composed of (>=20mol%) 3,3',4,4'- benzophenonetetracarboxylic acid dianhydride and a diamine component composed of (0.5-50mol%) 2,8-diaminodiphenylene oxide, (>=20mol%) 3,3'- diaminodiphenylsulfone and (0.1-30mol%) 1,3-bis(3-aminopropyl) tetramethyldisiloxane. The reaction of both components is carried out preferably at an equimolar ratio.

Description

Detailed Description of the Invention [Field of Industrial Application] 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 heptad ring in the polymer main chain. It is something. The purpose of this is that the cured resin diimidized by the ring-closing process has excellent heat resistance, abrasion resistance, chemical resistance, electrical insulation, film-forming properties, flexibility, mechanical properties, etc. as a polyimide resin. We provide heat-resistant resins that are useful as materials for electronic devices, electrical insulation materials, coatings, adhesives, paints, molded products, laminates, fibers, and film materials, among others, especially liquid crystals for electronic devices. An object of the present invention is to provide a heat-resistant resin useful as an alignment film for display elements.

[Prior art]

Conventionally, polymers having heterocycles such as imide, imidazole, thiazole, oxazole, oxadiazole, triazole, quinoxaline, thiadiazole, oxazinone, quinazoline, imidazopyrrolone, isoindoroquinazolone, etc. in the main chain of the polymer 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, elongation, or adhesiveness. Therefore, when used as an alignment film for liquid crystal, for example, it cannot withstand rubbing work and cannot fully align the liquid crystal, making it unable to function as a display element. In addition, when these polymers are heated during curing, they become significantly colored, becoming brown or blackish-brown. Therefore, when used as an alignment film for liquid crystal, for example, the liquid crystal display element becomes brownish, the field of view becomes dark, and the contrast deteriorates, resulting in poor display. It no longer functions as an element. From this point of view, various studies have been made in the past in order to achieve a balance between heat resistance, flexibility, light color property, and adhesiveness, but it has generally been the case that when one is good, the other is bad.

[Purpose of the invention]

As a result of studies aimed at overcoming these drawbacks, the present invention uses 2,8-diaminodiphenylene oxide, 3,3'-diaminodiphenylsulfone, and 1,3-bis(3-aminodiamine) as diamine components. Propyl) tetramethyldisiloxane and 3,3',4,4'-benzophenonetetracarboxylic dianhydride are used as essential components to improve heat resistance and flexibility. The present invention was completed based on the discovery that a heat-resistant resin with a good balance of light color and adhesiveness can be obtained.

[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
'-diaminodiphenylsulfone and 1,3-bis(3
-aminopropyl)tetrame, tildisiloxane and 3,3',4,4 as tetracarboxylic acid dianhydride.
This is a method for producing a heat-resistant resin, characterized in that '-benzophenone tetracarboxylic dianhydride is used as an essential component.

Among the diamines used in the present invention, essential components are 2°8-diaminodiphenylene oxide, 3,3'-diaminodiphenylsulfont, and 1,3-bis(3-aminopropyl)tetramethyldisiloxane. The reaction formula for one method of producing 2,8-diaminodiphenylene oxide is as follows.

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-phenyl diamine, p-7
22 diamine, 4.4'-diaminodiphenylpropane, 4.4'-diaminodiphenylmethane, benzici:y, 4e4'-diaminodiphenylsulfite, 4゜4'-diaminodiphenyl sulfone, 4.4'-diaminodiphenyl ether , 2,6-diamitubiridine, bis(4-7minophenyl)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-butylphenyl)ether,
p-bis(2methyl-4-7minopentyl)benzene,
p-bis(1,1-dimethyl-5-aminopentyl)benzene, m-xylylenediamine, p-xylylenediamine, bis(p-aminocyclohexyl)methane, ethylenediamine, propylenediamine, hexamethylenediamine, heptamethylenediamine , octamethylene diamine, nonamethylene diamine, decamethylene diamine,
3-methylhbutamethylenediamine, 4,4-dimethylhbutamethylenediamine, 2゜11-diaminodecane, 1.2-bis(3-aminopropoxy)ethane, 2.
2-dimethylpropylenediamine, 3-methoxyhexamethylenediamine, 2.5-dimethylhexamethylenediamine, 2.5-dimethylnonamethylenediamine, 1-
These include 4-diaminocyclohexane, 2,12-diaminooctadecane, and 2,5-diamino-1,3,4-oxadiazole.

Furthermore, among the tetracarboxylic dianhydrides used in the present invention, an essential component is 3.3', 4,4'-benzophenone tetracarboxylic dianhydride. However, other tetracarboxylic dianhydrides can of course also be used. For example, pyromellitic dianhydride, 2,3゜6.7-naphthalenetetracarboxylic dianhydride, 3゜3', 4,4
'-Diphenyltetracarboxylic dianhydride, It 2.
5.6-Naphthalenetetracarboxylic dianhydride, 2,2
', 3.3'-diphenyltetracarboxylic dianhydride, 2.2-bis(3,4-dicarboxydiphenyl)propane 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 Anhydride, 4,8-dimethyl-1,2°3.5,
6.7-Hexahydronaphthalene-1,2-5t6-tetracarboxylic dianhydride, 2.6-cyclonaphthalene-1.4,5t8-tetracarboxylic dianhydride, 2.7
-cyclonaphthalene-1.4,5.8-tetracarboxylic dianhydride, 2,3,4.7-titrachloronaphthalene-1.4,5.8-tetracarboxylic dianhydride, 7-enanthrene-1 .2,9.10-tetracarboxylic dianhydride, cyclopentane-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)propane dianhydride, 1,1-bis(2,3
-dicarboxyphenyl)ethane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride,
Bis(2,3-dicarboxyphenyl)methane dianhydride, bis(3,4-dicarboxyphenyl)sulfonic anhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, 1,2.3 .4-butanetetracarboxylic dianhydride, thiophene-213,4,5-tetracarboxylic dianhydride, and the like. The amount of 2,8-diaminodiphenylene oxide, which is an essential component, is 0.5 to 50 mol%.
It seems to contain. 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 2.
The amount is preferably 0 mole or more, and if it is less than this, the effect of improving coloration is small. Further, the amount of 1,3-bis(3-aminopropyl)tetramethyldisiloxane used is 0.1 to 30
The content is preferably mol%. If the amount is less than 0.1 mole, the effects of color-free and adhesive improvement will be small, and if it is more than 30 mole, the cured product will be brittle.

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 q/b 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, and N,N-dimethylformamide.
-diethylformamide, N,N-diethylacetamide, N,N-dimethylmethoxyacetamide, dimethylsulfoxide, hexamethylphosphoamide, N-methyl-2-pyrrolidone, pyridine, dimethylsulfone, tetramethylenesulfone, dimethyltetramethylenesulfone, 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, butyrolactone, 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 is ring-opened by water, becomes inactivated, and there is a risk of 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 the following various ways.

(1) Diamines and tetracarboxylic dianhydride are mixed in advance, and the mixture is added little by little to an organic solvent while stirring. This method is relatively advantageous in exothermic reactions such as those for polyimide resins.

(2) Conversely, there is also a method in which a solvent is added to a mixture of diamines and tetracarboxylic dianhydride while stirring once.

(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 the 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 diamino compound of 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. This is because if the temperature is 0°C or lower, the reaction rate is slow, and if the temperature is 100°C or higher, the produced polyamic acid gradually starts the ring-closing reaction.

Usually, the reaction is carried out at around 20°C. The degree of polymerization of polyamic acid can be controlled in a planned manner.

In order to control the degree of polymerization, it is also possible to end-block with phthalic anhydride or aniline, or add water to ring-open one of the acid anhydride groups to inactivate it.

The polyamic acid product produced by the method of the present invention can be used with various silane coupling agents, borane coupling agents, titanate coupling agents, aluminum coupling agents, and other chelate-based adhesives. -Adhesion improvers, various solvents, and flow agents may be added, and in addition to these, a small amount of a normal acid curing agent, amine curing agent, polyamide curing agent, and curing accelerator such as imidazole or tertiary amine may be added. Also, flexibility agents and viscosity modifiers such as rubber, polysulfide, polyester, and low-molecular epoxy, fillers such as talc, clay, mica, feldspar powder, quartz powder, and magnesium oxide, carbon black, and phthalocyanine blue. Small amounts of colorants such as, flame retardants such as tetrabromophenylmethane, tributyl phosphate, flame retardant aids such as antimony trioxide, barium metaborate, etc. may be added, and these additions can be used in many applications. will be held.

The polyamic 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, the atmosphere may be air, but it is often preferable to use a non-Australian atmosphere such as reduced pressure or an inert gas. As the latter dehydrating agent, carboxylic anhydrides such as acetic anhydride, propionic anhydride, and benzoic anhydride are often used. Examples of solid dehydrating agents include zeolite-based Molechier Sheep, silica gel, and activated alumina, which are more effective when used after being slightly heated.

〔Effect of the invention〕

According to the method of the invention, 2,8-diaminodiphenylene oxide, 3,3'-diaminodiphenylsulfone, 1,3-bis(3-aminopropyl)tetramethyldisiloxane, 3,3',4, A polymer containing 4'-benzophenone tetracarboxylic dianhydride as an essential component is an excellent heat-resistant resin that has a good balance of heat resistance, flexibility, light color, and adhesiveness.

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

Furthermore, by introducing 3,3'-diaminodiphenylsulfone and 4.4'-benzophenonetetracarboxylic dianhydride, a heat-resistant resin with less coloring can be obtained, probably because the main chain cannot form a conjugated structure. . Furthermore, by introducing 1,3-bis(3-aminopropyl)tetramethyldisiloxane, the imide group content is diluted, resulting in less coloring.
Moreover, a heat-resistant resin with good adhesiveness can be obtained.

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, it is a wiring structure for electronic circuits such as semiconductors, transistors, linear ICs, hybrid ICs, light emitting diodes, LSIs, and very large scale integrated circuits.

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 nemate liquid crystals such as ship base type liquid crystals, phenylcyclohexane type liquid crystals, azoxy type liquid crystals, azo type liquid crystals, biphenyl type liquid crystals, ester type liquid crystals, phenyl-pyrimidine type liquid crystals, and the above-mentioned liquid crystals. Examples include cholesteric liquid crystals in which optically active compounds such as optically active substances 5, cholesterol compounds, biphenyl derivatives having optically active substituents, and phenylbenzoates are added to nematic liquid crystals. It is also used as a coaching varnish for high temperatures, such as electric wire coating, magnet wire, dip coating for various electrical parts, and protective coating for metal parts.It is also used as an impregnating varnish for glass cloth, fused silica cloth, graphite fiber, and boron fiber. Used for impregnation, used in radar domes, printed circuit boards, radioactive waste containers, turbine blades, spacecraft and other structural parts that require high temperature performance and good electrical properties, and for microwave protection and radiation protection. It is also used as an interior material for waveguides in computers, atomic equipment, and X-ray equipment.

It is also used as a molding material to create self-lubricating sliding surfaces by adding graphite powder, graphite fiber, molybdenum disulfide, and polytetrafluoroethylene, and is used for piston rings, valve seats, bearings, seals, etc. In addition, by adding glass fiber, graphite fiber and boron 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 Purified anhydrous 2,8-diaminodiphenylene oxide 19.823 was placed in a four-neck separable flask equipped with a thermometer, a stirrer, a raw material inlet, and a dry nitrogen gas inlet.
F (10 moles), 3,3'-diaminodiphenylsulfone 173.810 f (70 moles), 1
, 49.704 PC (20 mol%) of 3-bis(3-aminopropyl)tetramethyldisiloxane), and a mixed solvent of 95% by weight of anhydrous N-methyl-2-pyrrolidone and 5% by weight of toluene was added to this. The solid content ratio in the raw material is 1
An amount sufficient to make 5% by weight was added and melted. Dry nitrogen gas was kept flowing throughout the entire process from the preparatory stage of the reaction to the removal of the product.

Then purified anhydrous 3.3', 4.4'-benzophenonetetracarboxylic dianhydride 3:11230 f
(100 mol mole was added little by little while stirring, but since it was an exothermic reaction, it was cooled by circulating cold water of about 15 °C in an external water tank.The internal temperature of the addition diameter was set at 20 °C, and it was cooled for 12 hours. The mixture was stirred to complete the reaction.

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 0.62 (30°C).

Next, a 5% by weight solution of this polyamic acid with N-dimethylacetamide was dropped onto a glass plate.
It was spun with a spinner at 40 Orpm/min for 10 seconds followed by 2000 rpm/min for 20 seconds to ensure uniform application. This was heated at 80°C for 150' under reduced pressure.
The mixture was sequentially heated at 1250° C. and 350° C. for 30 minutes each to cause dehydration and ring closure, thereby obtaining a pale yellow transparent and strong polyimide resin film with a thickness of 1 μm. Looking at the infrared absorption spectrum of this film, it is 1780 cm-1 and 730 cm-1.
"strong absorption based on the imide ring and 1200 cyn-
”, 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 500°C at a heating rate of 5°C/min, as measured by a differential thermal balance 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 93% at 400 nm. Furthermore, a sellotape peeling test on a glass plate (JIS-D-
0202) had a peeling rate of 0 and excellent adhesion.

Example 2 2,8-diaminodiphenylene oxide (39.646 f) was prepared using the same apparatus and method as in Example 1.
%) 3+3'-diaminodiphenylsulfone 14
&980f (60 mol qb) and 4,4'-diaminodiphenyl ether 20.0249 (10 mol qb) and 1
, 24.852 t (10 mol qb) of 3-bis(3-aminopropyl)tetramethyldisiloxane, 3.
3'1414'-benzophenonetetracarboxylic dianhydride 161.115P (50 mol%) and pyromellitic dianhydride 109.060? (50 molti) was reacted.

The obtained product was a transparent yellow and extremely viscous polyamic acid solution with an intrinsic viscosity of 0.75. The obtained film was pale yellow and transparent, and had excellent toughness, with a thermal decomposition initiation temperature of 505°C, a hot tensile strength of 16 kq/■, a light transmittance of 89%, and a peeling rate of cellophane tape of 0%. Ta.

Comparative Example 1 Using the same equipment and method as in Example 1, 3,3'-diaminodiphenylsulfone 24&300F (100% ruti)
and 3.3', 4.4'-benzophenonetetracarboxylic dianhydride 32λ230? (100 mol.

The obtained film had excellent light color property, but the thermal decomposition initiation temperature was only 305°C, the hot tensile strength was only 4 kf/2, and the cellophane tape peeling rate was 90 cm, which was poor. It was not something that could withstand rubbing work.

Comparative Example 2 Using the same apparatus and method as in Example 1, 3+3't=, diaminodiphenylsulfone 19 & 640 f (80 mol) and 1,3-bis(3-aminopropyl)tetramethyldisiloxa 749.704 f (20 MoA[) and 3
, 3', 4,4'-benzophenonetetracarboxylic dianhydride 322.230 r (100 mol %) were reacted.

The obtained film had excellent light color and good adhesion, but the thermal decomposition initiation temperature was only 320° C. and the hot tensile strength was less than 5 Ume/mL.

Comparative Example 3 Using the same apparatus and method as in Example 1, 2,8-diaminodiphenylene oxide 19.8239 (10 molti)
and 3,3'-diaminodiphenylsulfone 223.4
70? (%' to 90 mo) G, 3+ 3'+ 4+
4'-Hairsiphenone tetracarboxylic dianhydride 3
2Z230 F (100 mol qb).

The obtained film had excellent light color property, high thermal decomposition initiation temperature, and strong hot tensile strength, but the cellophane tape peeling rate was poor at 100%.

Claims (5)

[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, 3,3'-diaminodiphenylsulfone, and 1,3-bis(3-aminopropyl)tetramethyldisiloxane. (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. (5) The heat-resistant resin according to claim 1, which contains 0.1 to 30 mol% of 1,3-bis(3-aminopropyl)tetramethyldisiloxane as a diamine component. manufacturing method.