JPS60161429A - Preparation of heat-resistant resin - Google Patents

Abstract

PURPOSE:To prepare a heat-resistant resin having extremely high thermal decomposition starting temperature, improved wear resistance, chemical resistance, etc., by reacting a specific tetracarboxylic acid dianhydride with a specified amine in an anhydrous state under an inert gas condition. CONSTITUTION:A tetracarboxylic acid dianhydride consisting of 99-80mol% tetracarboxylic acid dianhydride such as pyromellitic dianhydride shown by the formula I (R1 is benzene ring or condensed benzene ring) and 1-20mol% tetracarboxylic acid deanhydride such as benzophenone-tetracarboxylic acid dianhydride shown by the formula II (X1 is -CO-, -SO2-, etc.) is reacted with a diamine shown by the formula H2N-R2-NH2 (R2 is as shown for R1) such as 99-60mol% paraphenylenediamine and 1-40mol% diamine 4,4'-diaminodiphenyl ether shown by the formula III (X2 is as shown in X1) in an anhydrous state in an inert gas atomosphere in an organic polar solvent at 0-100 deg.C, to prepare a resin having 0.5-2.5 intrinsic viscosity of reaction product of polyamic acid, and 480-580 deg.C thermal decomposition starting temperature of a cured material after imidation.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a heat-resistant resin using a tetracarboxylic dianhydride and a diamine as raw materials. The purpose of this is that the cured resin imidized by the ring-closing process has a significantly high thermal decomposition onset temperature, and that it has good abrasion resistance, chemical resistance, electrical insulation, and film properties as a polyamide resin. , excellent mechanical properties, adhesion, flexibility, etc.
The object of the present invention is to provide a heat-resistant resin useful as an electrical insulating material, a doping agent, an adhesive, a paint, a molded product, a laminate, a fiber or a film material, etc.

Conventionally, diamines containing at least two carbon atoms are
A tetravalent group containing a tetravalent group containing at least two carbon atoms, and in which at most two of the carbonyl groups of the dianhydride group are bonded to any one of the carbon atoms of the tetravalent group. reacted with a carboxylic dianhydride to form a cibolyamic acid product, which was then heated at 50'C.
It is well known to produce polyimides by heating to high temperatures to convert the bulk polyamic acid product to polyimide. The produced polyimides are characterized by having repeating units consisting of diamine and tetracarboxylic dianhydride groups, and furthermore, the siaquine group is a divalent group containing at least two carbon atoms. group, once the tetracarboxylic dianhydride group contains a divalent group containing at least 2 carbon atoms, at most two of the carbonyl groups of the dianhydride group are tetravalent groups. It is also known that it is characterized in that it is bonded to any one of the carbon atoms. Furthermore, bitetracarboxylic dianhydride is used as tetracarboxylic dianhydride.

Benzophenone tetracarboxylic dianhydride, 2. &6.
7-Naphthalenetetracarboxylic dianhydride, 3°3?
4.4'-diphenyltetracarboxylic dianhydride.

1+ 2-5.6-Naphthalenetetracarboxylic dianhydride.

2+2'=3+3', -diphenyltetracarboxylic dianhydride.

2.2-hyx (3w4-dicarboxydiphenyl)
Furopansi m hydrate, 3*4+9dO-perylenetetracarboxylic dianhydride, bis(3,4-dicarboxydiphenyl)ether dianhydride, ethylenetetracarboxylic dianhydride, s7talene-1=2-4*5- Tetracarboxylic dianhydride, naphthalene-1s4+5+8-tetracarboxylic dianhydride-decahydronaphthalene-1,4,5,
8-Tetracarboxylic dianhydride 54-8-dimethyl-1
*2-3,5,6,7-hexahyto is naphthalene-1+
2.5,6-Tetracarboxylic dianhydride 2,6-cyclonaphthalene-1m44*8-Tetracarboxylic dianhydride, 2,7-dichloro-naphthalene-1,4°5.8
-Tetracarboxylic dianhydride, 2.3.4.7-titrachlorona7talene-L4. L8-Nato 2 carboxylic acid dianhydride, 7 enanthrene! $8-9110-9) Lacarboxylic dianhydride, cyclopentane-L2.3゜4-tetracarboxylic dianhydride, pyrrolidine-2゜3,415
-tetracarboxylic dianhydride, pyrazine-2,3,5,
6-tetracarboxylic dianhydride, 2,2-bis(2,5
-dicarboxyphenyl)propane dianhydride, 1. l-
Bis(213-dicarboxyphenyl)ethane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, bis(3,4- dicarboxyphenyl)
Methane dianhydride, bis(L4.-dicarboxyphenyl)sulfone dianhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, etc. are used, and diamines such as m-phenylenediamine and p-7enyl dianhydride are used. diamine,
4.4'-diaminodiphenylmethane, 4.4'-diaminodiphenylmethane, benzidine, 4.4'-diaminodiphenylsulfide, 4.4'-diaminodiphenylsulfone, L3'-') aminodiphenylsulfone, 4-4'- Diaminodiphenyl ether, 2,6-diadenoviridine, bis(4-aminophenyl)phosphine oxyto, bis(4-aminophenyl)-N-methylamine, l,5-diaminonaphthalene, 3,3'-dimethyl-414 '-Diaminobiphenyl, 3゜3'-dimethoxybenzidine, 2,4-bis(β-amino-t-butyl)toluene, bis(p-β-amino-t-butylphenyl)ether, p-bis(2- Methyl-4-aminopentyl)benzene, p-bis(1,1-dimethyl-5
-aminopentyl)benzene, m-xylylenediamine, p-xylylenediamine, bis(p-aminoschifftetrahexyA/)methane, ethylenediamine, tetrapyrenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nona methylene diamine,
Decamethylenecyadenine, 3-methylhbutamethylenediamine, 4I4-dimethylhbutamethylenediamine, 2t
ll-cyaelectronododecane, 1,2-bis(3-aminopropoxy)ethane, 2,2-dimethylp4pyrenethia 2
3-methoxyhexamethylene diane, 2,5-dimethylhexylylene diamine, 5-methylnonamethylene diane, 1゜4-diaminoxyhexane, 1+12
-cyaminooctadecane, 2,5-diamino-1t3.
The use of 4-oxadiazole, etc. has also already been demonstrated.

However, in electronics, OA equipment, robots, nuclear power, aerospace, and other so-called cutting-edge technology industries, there is a strong demand for equipment to become more highly integrated, lighter, thinner, and smaller, and ultra-precise in harsh usage environments. Initially, there was a strong demand for polyimide resins used in these products to have very high heat resistance, but until now no one had been found that had a thermal decomposition onset temperature of 480°C or higher. For example, DuP
Polyimide resin varnish PyreML manufactured by ont (USA)
The thermal decomposition initiation temperature of the cured product (2) is only 400°C.

The present inventors have conducted intensive research with the aim of increasing the thermal decomposition initiation temperature to 480°C or higher while maintaining the excellent properties of polyimide resin (R1 is a benzene ring, a condensed benzene ring). Tetracarboxylic dianhydride (A
)99~8O-f-ruqk and (X, -CO-1-needle, -SO, -1-S-1-CH
Tetracarboxylic dianhydride represented by 2-1 @1-2
Tetracarboxylic acid dianhydride consisting of 0 molti and the general formula H, N -R, li- (R, is a benzene ring, fused benzene ring) (X, ei-
A diamine consisting of 1 to 40 moles of cyanine represented by CO-1-CH, -5O2-1-S-1-CH,-1 is added to an organic diamine in an inert gas atmosphere under anhydrous conditions. By reacting in a polar solvent at 0 to 100°C and adjusting the intrinsic viscosity of the polyamic acid product to α15° to 25, a completely new and highly heat-resistant polyimide resin with a thermal decomposition onset temperature of 480 to 580°C can be obtained. This fact was discovered and the present invention was completed.

That is, the feature of the present invention is that Ml! As a result of a detailed study of the cause, the new knowledge was obtained that the degree of polymerization of the resin as well as the resin structure has a significantly large influence. Until now, various efforts have been made to improve the heat resistance of K. That is, the first method is to increase the stability of the bonds contained in the resin, or in other words, the energy of the bonds as much as possible. The heat resistance of aliphatic chain resins consisting only of single bonds is extremely poor. This means that the bond energy of a single bond is, for example, C-C (80Kcal/mo
l), CN (62Kcal/mol), which is small. On the other hand, the bond energies of double bonds and triple bonds are, for example, C=C (142Kcal/mol), C=
C (j86Kcal/mol), C=N (121K
cal/mol), CE N (191Kcal/
mol) It's as big as you can get. Therefore, in order to improve heat resistance, it is necessary to introduce multiple bonds, aromatic rings, etc. into the main chain of the resin. Since aromatic rings and polychoric rings are stabilized by resonance, they are considered to be advantageous in further improving heat resistance.

The second method is to introduce an aromatic ring with good symmetry into the main chain of the resin to increase the melting point and glass transition point. In general, the melting point (hereinafter referred to as Tm) and the enthalpy of melting (hereinafter referred to as △
b) and the melting end. Here △b
is related to the intermolecular force, and 68m is a quantity mainly related to the flexibility and symmetry of molecules. It is known that Tm is often influenced more by 68m than by ΔHm, and the more para-bonded aromatic rings there are in the main chain of the resin, the smaller 68m becomes and the higher Tm becomes. That is, in order to improve heat resistance, it is necessary to introduce an aromatic ring with good symmetry. The theory for improving heat resistance has been developed based on this model, and the molecular structure of heat-resistant resins has been designed based on this theory. However, the heat resistance referred to here refers to the so-called thermal decomposition temperature, and research has mainly focused on the temperature at which decomposition occurs violently. In the present invention, the problem is not the conventional thermal decomposition temperature, but the thermal decomposition initiation temperature, which is the temperature at which decomposition begins. There has not been much research on this until now. As a result of the inventors' detailed study of thermal decomposition temperature and thermal decomposition initiation temperature, we found that a high thermal decomposition temperature does not necessarily mean a high thermal decomposition initiation temperature. I have learned that there is no limit. Of course, in order to improve heat resistance, molecular design based on the theory is basic, and it is clear that the multimolecular structure has the greatest effect, but on top of that, the degree of resin polymerization is extremely high as it does not reach the thermal decomposition initiation temperature. I discovered that. In other words, this is a completely new finding that the lower the resin polymerization degree, the higher the thermal decomposition initiation temperature. Generally, the higher the resin polymerization degree, the higher the thermal decomposition temperature, and this is theoretically clear. However, it was not known until now that the temperature at which thermal decomposition begins is lower.

The thermal decomposition initiation temperature referred to herein refers to the temperature at which the loss of shrinkage due to heating begins as measured by differential thermal balance analysis. The reason why the thermal decomposition onset temperature is low is not clear, but in addition to the original thermal decomposition in which side chain functional groups with weak bonding energy or single bonds in the main chain are broken due to the molecular structure, polyamic acid In resins with a high degree of polymerization, volatile components such as water, unreacted raw materials, and residual bath agents generated during ring-closing treatment by methods such as heating generally cannot be volatilized due to their high melt viscosity and are stuck in the cured resin. It is thought that this is because it becomes engrossed. The degree of resin polymerization is mainly determined by the molar ratio of raw materials tetracarboxylic dianhydride and diamine, and increases as the molar ratio approaches 1. However, even if the molar ratio is constant, reaction conditions such as raw materials It can be adjusted by adjusting the purity, water content, reaction temperature, reaction time, amount of reaction terminator, reaction solvent system, etc.

The method of the present invention uses 99 to 80 moles of tetracarboxylic dianhydride represented by υ U (Ro is a benzene ring, fused benzene ring) and -CH
Tetracarboxylic dianhydride represented by 2-1 @1-2
Tetracarboxylic dianhydride consisting of 0 molti and the general formula H2N -R2-NH2 (R1 is a benzene ring, fused benzene ring) (x2 is (needle,
A diamine consisting of 1 to 40 mol of diamine (2) represented by -can, -SO, -1-S-1-CH2=, under anhydrous conditions, in an inert gas atmosphere, in an organic polar solvent. The polyamic acid product reacted at 0 to 100°C has an intrinsic viscosity of 0.5 to 2.5, and the heat-resistant resin has a thermal decomposition initiation temperature of the cured product after imidization of 480 to 580°C. This is the manufacturing method.

The tetracarboxylic dianhydride (2) in the present invention has the effect of increasing the thermal decomposition initiation temperature.

Among the compounds represented by the above, those in which R1 is a benzene ring or a fused benzene ring are highly effective, and among these, pyromellitic dianhydride is particularly excellent. When the proportion of tetracarboxylic dianhydride in the tetracarboxylic dianhydride component in the resin is high, the thermal decomposition initiation temperature becomes high, but the resin becomes rigid.

The tetracarboxylic dianhydride (B) in the present invention has the effect of improving the rigidity of the resin.

The compound represented by has excellent flexibility due to the single bond in the main chain sandwiching X□ that connects the aromatic rings.

As for Xo, -C0-1-ken, -SO□-1-8-, -
CH2-, benzophenone tetracarboxylic dianhydride is excellent. The higher the proportion of tetracarboxylic dianhydride (6) in the tetracarboxylic dianhydride component in the resin, the better the rigidity will be, but since the desired thermal decomposition initiation temperature will be lowered, It is preferable that the amount of the anhydride is 80 mol or more, whereas the amount of the tetracarboxylic dianhydride CB) is 20 mol or less.

The diamine (C) in the present invention has the effect of increasing the thermal decomposition initiation temperature.

Among the compounds represented by the general formula H2N -R2-NH2, those in which R2 is a benzene ring or a condensed benzene ring are highly effective, and among these, Temovara phenylenediamine is particularly excellent. The higher the proportion of diamine (C) in the diamine component in the resin, the higher the temperature at which thermal decomposition starts, but the resin becomes more rigid.

The diamine (b) in the present invention is a compound that is expressed by changing the rigidity of the resin and has excellent flexibility due to the main chain single bond sandwiching x2 that connects the aromatic ring.

For X2, -α, -needle, -5O2-1-s-1-C
H2-14,47-diamitudiphenyl ether is excellent.

The higher the proportion of diamine in the diamine component in the resin, the better the rigidity will be, but the target thermal decomposition start temperature will be lower. It is preferable that

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 diamine. 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. A typical example of this type of solvent is N,N-dimethylsulfone.

N,N-dimethylacetamide, N,N-diethylformamide, N,N-diethylacetamide, N,N-dimethylmethoxyacetamide, dimethylsulfoxide,
Examples include hexamethylphosphoamide, N-methyl-2-pyrrolidone, pyridine, dimethylsulfone, tetramethylenesulfone, and dimethyltetramethylenesulfone, and these solvents may be used alone or in combination. Benzene is also used in combination as a sacrificial medium.

Benzonitrile, dioxane, butyrolactone.

xylene, toluene, cyclohexane nanononsolvents,
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 inactive, and there is a risk of stopping the reaction. For this reason, it is necessary to remove both the moisture in the raw materials and the moisture in the solvent. However, in order to adjust the progress of the reaction and control the degree of resin polymerization, water is sometimes intentionally added.

Further, the present invention is preferably carried out in an inert gas atmosphere. This is to prevent oxidation of the diamine. Dry phonetic gas is generally used as the inert gas.

The reaction in the present invention can be carried out in the following various ways.

(2) Diamine and tetracarboxylic dianhydride are mixed in advance, and the mixture is added little by little into 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 of adding a solvent to a mixture of diamine and tetracarboxylic dianhydride while stirring.

(2) A commonly used method is to dissolve only the diamine in a solvent, and then add tetracarboxylic dianhydride to it in a proportion that allows the reaction rate to be controlled.

■It is also possible to dissolve the diamine and the tetracarboxylic dianhydride separately in a solvent and slowly add the two solutions in a reactor.

■In summer, it is also possible to prepare in advance a polyamic acid product containing an excess of diamine and a polyamic acid product containing an excess of tetracarboxylic dianhydride, and then further react them in a reactor. The reaction temperature is preferably 0 to 100°C. This is because if the temperature is below 0°C, the reaction rate is slow, and if it is above 100°C, the produced polyamic acid gradually starts the ring-closing reaction.

Usually, the reaction is carried out at around 20°C in a reactor, and cooling is required because it is an exothermic reaction. The degree of polymerization of polyamic acid can be controlled in a planned manner. When the tetracarboxylic dianhydride and diamine are close to 100 molar, the degree of polymerization becomes large. If either one of the raw materials is present in an amount of 5 or more, the degree of polymerization decreases significantly. Generally, it is common practice to use 1 to 3 times more of one raw material in terms of workability and processability. In order to control the degree of polymerization, one of the acid anhydride groups can be ring-opened and inactivated by adding water to the end-capped group with phthalic anhydride or aniline.

The intrinsic viscosity of the polyamic acid product in the present invention is 0.
5 to 2.5 is preferable, and lower than L-h00.5 is good for improving the thermal decomposition start temperature, but the thermal decomposition temperature should be low.
Film forming properties are also reduced. If it is higher than 2.5, the film forming property will be excellent, but the thermal decomposition starting temperature will be lowered.

When using the polyamic acid product produced by the method of the present invention, various silane coupling agents, borane coupling agents, titanate coupling agents, aluminum coupling agents and other chelate-based adhesives can be used. Properties improvers, various solvents, and flow agents may be added, and in addition to these, small amounts of ordinary acid curing agents, amine curing agents, boria curing agents, and curing accelerators such as imidazole and tertiary amines may be added. Also, flexibility additives and viscosity modifiers such as polysulfide, polyester, low molecular epoxy, Merck, clay, mica, feldspar powder,
Fillers such as quartz powder, magnesium oxide, coloring agents such as carbon black and ferrocyanine blue, flame retardants such as tetrabromophenylmethane and triptyl phosphate, antimony trioxide, and barium metaphoate. Small amounts of combustion aids may also be added, and their addition opens up many applications.

Specifically, the present invention is used as a coating film for preserving the surface 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/sisters, linear ICs, hybrid ICs, light emitting diodes, LSIs, and very large scale integrated circuits. Furthermore, it is used for other purposes such as imparting heat resistance to various materials, preventing microwaves, and preventing radiation. Examples include waveguides for combinators, nuclear equipment, interior materials for X-ray equipment, and the like.

Next, it is used as a high-temperature coating varnish, such as electric wire coating, magnet wire, dip coating for various electrical parts, and eye protection coating for metal parts.It is also used as an impregnation varnish for glass cloth, fused silica cloth, etc.
It is used to impregnate graphite and boron fibers for use in radar domes, printed circuit boards, radioactive waste containers, turbine blades, spacecraft and other structural components that require high temperature performance and excellent electrical properties. Graphite powder, graphite fiber, polydenum disulfide, and polytetrafluoroethylene are also added as molding materials and used to create self-lubricating sliding surfaces for piston rings, valve seats, bearings, seals, etc. It is also used to add glass fiber, graphite fiber and boron fiber to jet engine parts,
High-strength structural molded parts are made. Furthermore, it is used as a high-temperature adhesive for bonding electrical circuit parts and structural parts of spacecraft.

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

Example 1 1 mol of the purified anhydrous diamine listed in Table 1 was added to a 4-tube flask equipped with a temperature needle, a stirrer, and a dry nitrogen gas inlet, and then anhydrous N was added.

A mixed solvent of 95% of N-dimethylacetamide and 5% of anhydrous diacetone alcohol was added and dissolved in an amount sufficient to make the solid content of the total raw materials 15%. Next, 1 liter of the purified anhydrous tetracarboxylic dianhydride listed in Table 1 was added little by little while stirring, while cold water at about 15°C was circulated to stop the rapid exothermic reaction from outside. It was cooled down. After the addition, the internal temperature was set at 20°C and stirring was continued for 10 hours to advance the reaction, but the viscosity of the reaction system gradually increased. During this process, samples were taken one after another and their characteristics were determined using the method described below. That is, a portion of the collected sample was poured into water to precipitate polyamic acid, which was filtered and dried under reduced pressure. The product was dissolved in 100111t of QN-methyl 2-pyrrolidone and its intrinsic viscosity was measured at a temperature of 30°C using an Ubbelohde capillary viscometer. Further, another portion of the collected sample was diluted with N-methyl-2-pyrrolidone to a concentration of 5% and cast onto a glass plate while rotating a wheeler at tsorpm/min. Under reduced pressure,
0°C, then 150°C, 250°C, 350°C and 3 times each time.
When heated sequentially for 0 minutes at a time, dehydration and ring closure occur, resulting in imidization, and a film with a thickness of 2 to 3 μm is completed. The thermal decomposition start temperature and thermal decomposition temperature of the film were measured using a differential thermal balance analyzer at a heating rate of 5° C./min in air.

The results are shown in Table 1.

As shown in Table 1, the thermal decomposition initiation temperature increases as the intrinsic viscosity increases. This has been known for a long time and is no surprise. However, when looking at the thermal decomposition start temperature, it is higher for #1, which has a lower intrinsic viscosity. This fact was completely unknown and surprising. It is not clear why the smaller the intrinsic viscosity, the higher the temperature at which thermal decomposition begins, but it is due to the inherent heat that breaks the side chain functional group, which has a weak bond energy in the molecular structure, or the single bond in the main chain. In addition to decomposition, volatile components such as water, unreacted raw materials, and residual solvents generated when polyamic acid is subjected to ring-closing treatment by methods such as heating, are released due to the high melt viscosity of resins with a high degree of polymerization. This is thought to be because it is trapped in the cured resin without being able to volatilize.

Furthermore, as shown in Table 1, the compounds that can maintain a thermal decomposition initiation temperature of 480°C or higher are pyromellitic dianhydride (working number A1.2.3.4) and 2.3.6.7-naphthalene. The tetracarboxylic dianhydride component of tetracarboxylic dianhydride (working number 6, 7.8), p-phenylenediamine (working number 1.6) and m-phenylenediamine (
The main diamine components are 2.7-diamitunaphthalene (2.7) and 2.7-diamitunaphthalene (43.8). limited to those that Among these, those containing a benzene ring are better, but this is because the chemical reactivity of the fused benzene ring is somewhat low, and the molecular arrangement during heat curing is well ordered due to its structural cover. This is thought to be because it is not carried out. Furthermore, among those containing a benzene ring, when p-phenylenediamine and m-phenylenediamine are compared, p-phenylenediamine is superior. This is considered to be due to the thermodynamically obvious reason that the entropy change of p-bonds is smaller than that of m-bonds.

Furthermore, as is clear from Table 1, the film properties are better as the intrinsic viscosity increases. This fact has been known for a long time. Furthermore, it can be seen that compounds having a flexible single bond in their molecular structure, ie, benzophenone tetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether, are excellent. However, on the contrary, it is inferior in heat resistance.

Example 2 According to Example 1, pyromellitic dianhydride was selected as the tetracarboxylic dianhydride component, which had the highest thermal decomposition initiation temperature, and p-phenylenediamine was selected as the amine component, and tetracarboxylic acid, which had the best film properties, was selected. Selecting benzophenonetetracarboxylic dianhydride as the acid dianhydride component and 4゜4'-diaminodiphenyl ether as the amine component, they were reacted using the same method as in Example 1 at the charging ratios shown in Table 2, and their properties were determined. was measured.

The results are shown in Table 2.

According to Table 2, those having thermal decomposition start temperatures of 480° C. or higher are implementation numbers A1-4.6-9.11-14. Among the tetracarboxylic dianhydride components, when the charging ratio of benzophenone tetracarboxylic dianhydride exceeds 20 molt (Example No. 416.17.18.19.20), the thermal decomposition initiation temperature decreases below 480 ° C. become. Next, among the diamine components, the charging ratio of 4゜4'-diaminodiphenyl ether exceeds 40 molt (Execution number / I65.10.1
Similarly to 5.20), the thermal decomposition start temperature does not reach 480°C. As a result, in order to set the thermal decomposition initiation temperature to 480°C, the amount of pyrmellitic dianhydride in the tetracarboxylic dianhydride component was increased to 80 mol or more, and the amount of p-phenylenediamine in the diamine component was increased to 60 mol or more. I understand that it is necessary. Film properties are largely related to intrinsic viscosity, and it is considered that the film cannot be used unless the intrinsic viscosity is 05 or higher.

Further, those having an intrinsic viscosity of more than 2.5 have excellent film properties by themselves, but the thermal decomposition initiation temperature becomes lower than 480°C. This results in an intrinsic viscosity of 0.5 to 2.5
I know it has to be.

Example 3 According to the method of Example 2, with the raw material charging ratios listed in Table 3,
A polyamic acid product with an intrinsic viscosity of 1.5 was obtained. This product was diluted with N-methyl-2-pytetralidone to a concentration of 20
Using a spinner, the sample was cast to a thickness of about 10 μm onto the surface of a silicon semiconductor device on which a fine circuit was formed. This was heated to 80℃, then 150℃, 2
An imidized resin film was created by heating at 50°C and 350°C for 30 minutes each. The performance of this film is shown in Table 3.

Example No. A1 in Table 3 is a polyimide resin containing only pyromellitic dianhydride and p-phenyl diamine. Although it has excellent heat resistance and electrical properties, it is among the highest in class, but because the proportion of aromatic rings in one unit of the resin's molecular structure is too large, the resin is rigid, and the various coatings are different. It is difficult to use the product in an environment where there are mechanical shocks and frequent changes in temperature and humidity. Further, the shrinkage during curing is extremely large, and the film on the surface of an electronic circuit element on which a fine circuit is formed may break or damage the circuit due to the shrinkage, so that it lacks practical reliability. Also, implementation number A6.8 in Table 3
．． Sample No. 9 used a large amount of benzophenone tetracarboxylic acid anhydride or 4,4'-diaminodiphenyl ether, which was outside the scope of the present invention, so although the film properties were excellent, the thermal decomposition initiation temperature did not reach 480°C. The withstand voltage is also low. Such polyimide resins cannot withstand high temperatures during hermetic sealing of elements, and cannot be applied to power transistors that are loaded with high bias. In contrast, implementation numbers 42.3.4.5 and 7f1 in Table 3
7 is according to the present invention and is pyromellitic dianhydride 99-
Tetracarboxylic dianhydride consisting of 80 molt and 1 to 20 molt of benzophenone tetracarboxylic dianhydride, 99 to 60 molt of p-phenylenediamine, and 4.4'
- Diaminodiphenyl ether 1-40 min. As is clear from these results, the higher the proportion of benzophenonetetracarboxylic dianhydride in the tetracarboxylic dianhydride, the lower the thermal decomposition onset temperature becomes, but temperatures above 480°C are poor, and the electrical properties and film properties are excellent. There is. Furthermore, as the proportion of 4,4'-diaminodiphenyl ether in the diamine increases, the thermal decomposition initiation temperature decreases as described above, but it remains at 480 DEG C. or higher, and the electrical properties and film properties are excellent. Furthermore, #1, which has a large amount of 414'-diaminodiphenyl ether, has excellent adhesion to the substrate because it has one o-t- of ether in its molecular structure.

As described above, the polyimide resin of the present invention is a novel polymer having an unprecedentedly high thermal decomposition initiation temperature and excellent other properties.

applicant Sumitomo Bakelite Co., Ltd.

Claims (1)

[Scope of Claims] 1. Tetracarboxylic acid dianhydride (2) represented by the general formula (R, habenyne ring, condensed benzene ring) and (Xl is -CD-1-th, -5O2- 1-S-1-CH
Tetracarboxylic dianhydride represented by 2-1 @1-2
A tetracarboxylic dianhydride consisting of 0 molti and the general formula H, N -R, -NH. (R1 is a benzene ring, fused benzene ring) diamine (C) 99 to 60 mol and (x2 is -CO
-1-needle, -5O2-1S 1 to 40 mol of diamine (6) represented by 5-CH2-1 and a colored diamine are mixed under anhydrous conditions in an inert gas atmosphere in an organic polar solvent, A method for producing a heat-resistant resin, in which a polyamic acid product reacted at 0 to 100°C has an intrinsic viscosity of 0.5 to 2.5, and a cured product after imidization has a thermal decomposition initiation temperature of 480 to 580°C. 2. The method for producing a heat-resistant resin according to claim 1, wherein (A) is bitemellitic dianhydride and [F]) is benzophenone tetracarboxylic dianhydride. 3. (C) Kabala phenylene diamine (B)
The method for producing a heat-resistant resin according to claims 1 and 2, wherein is 4-4'-diaminodiphenyl ether.