JP2019156862A - Rubber modified polyimide resin and polyimide resin solution - Google Patents

Abstract

To provide a novel polyimide resin capable of being used in various applications because it is excellent in heat resistance and has also solubility to methyl ethyl ketone or toluene or the like, which is a general-purpose organic solvent having low boiling point.SOLUTION: There is provided a rubber modified polyimide resin having a repeating unit represented by the following formula (1), where m and n are average repeating numbers, and represents a positive number satisfying relationships of 0<m≤200 and 0<n≤200, Qeach independently represents a bivalent aromatic group, Qeach independently represents a tetravalent aromatic group, and R each independently represents a bivalent aliphatic group.SELECTED DRAWING: None

Description

  The present invention relates to a polyimide resin having a high glass transition point, which is a rubber-modified polyimide resin soluble in a low-boiling general-purpose organic solvent.

  Polyimide resins have excellent heat resistance, electrical insulation, mechanical properties, and chemical resistance, and are therefore widely used in electrical, electronic components, semiconductors, communication devices, circuit components, and peripheral devices. However, since polyimide resin is poorly soluble in organic solvents, the film is processed by a process such as applying a polar solvent solution of polyamic acid, which is a raw material of polyimide resin, to a base material, etc., and then dehydrating and ring-closing to imidize. It has been a long-standing challenge to be a material that is difficult to apply except in the form of a material.

  Patent Document 1 discloses a polyimide resin having a phenolic hydroxyl group that is soluble in γ-butyrolactone. In recent years, polyimide resins having solubility in polar solvents such as N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, and dimethyl sulfoxide have also been found. It is applied to insulating films for flexible substrates. However, since these solvents have a high boiling point, the problem is that they can only be used in processes capable of high-temperature treatment, and polyimide resins soluble in methyl ethyl ketone and toluene, which are low-boiling general-purpose organic solvents, have been demanded.

Patent Document 2 discloses a block copolymerized polyimide soluble in a ketone solvent, an ether solvent, and an ester solvent, obtained from a diamine such as tetracarboxylic dianhydride and silicone diamine. The positive photosensitive composition containing the polyimide has excellent resolution, and the polyimide film made of the composition has the effect of not whitening due to moisture absorption by the solvent in the atmosphere, but is satisfactory in terms of adhesion and heat resistance. It is not possible.
In other words, polyimide resins that still have excellent properties such as heat resistance inherent in polyimide resins and that have low boiling points such as methyl ethyl ketone and toluene and that can satisfy solubility in general-purpose organic solvents are still not found in the market. The situation has not been issued.

Republished WO2010 / 044381 Republished WO2003 / 060010

  The present invention has been made in view of the above points, and is used for various applications by having excellent heat resistance and the like, and having solubility in methyl ethyl ketone, toluene and the like, which are low-boiling and general-purpose organic solvents. An object of the present invention is to provide a novel polyimide resin that can be used.

As a result of intensive studies, the present inventors have used the rubber-modified polyimide resin, which is a block copolymer having a polycondensation structure of a polyimide resin having a specific structure and a rubber-like aliphatic resin having a specific structure. The present inventors have found that the problem can be solved and completed the present invention.
That is, the present invention
[1] The following formula (1)

(In the formula (1), m and n are average repeat numbers and represent positive numbers satisfying the relationship of 0 <m ≦ 200 and 0 <n ≦ 200. Q ₁ is independently a divalent aromatic group. a tetravalent aromatic group in Q ₂ is independently, a rubber-modified polyimide resin having a repeating unit represented by the representative.) a divalent aliphatic group each R is independently,
[2] The following formula (1-1) or (1-2)

(Formula (1-1) and (1-2) _{in, m, n, Q 1,} Q 2 and R m in the formula (1) according to item _{[1], n, Q 1} , Q 2 and The same meaning as R.) The rubber-modified polyimide resin according to [1],
[3] A polyimide resin solution containing the rubber-modified polyimide resin and the organic solvent according to [1] or [2] above,
[4] The polyimide resin solution according to [3] above, which contains an organic solvent having a boiling point of 140 ° C. or lower, and [5] the polyimide resin solution according to [4], wherein the organic solvent contains at least one of methyl ethyl ketone or toluene. ,
About.

  The rubber-modified polyimide resin of the present invention is soluble in a solvent having a low boiling point such as methyl ethyl ketone and toluene while having a high heat resistance with a glass transition point of 170 ° C. or higher. Therefore, the low boiling point solvent solution of the polyimide resin can be used for various applications in a low temperature treatment process of 170 ° C. or lower.

Hereinafter, embodiments of the present invention will be described.
The rubber-modified polyimide resin of the present invention is a block copolymer of an aromatic polyimide resin having amino groups at both ends, which is a condensate of an aromatic tetracarboxylic dianhydride and an aromatic diamine compound, and an aliphatic dicarboxylic acid. It is.
When the aromatic polyimide resin and aliphatic dicarboxylic acid are copolymerized with an aromatic polyimide resin having an excess molar ratio to the aliphatic dicarboxylic acid, a rubber-modified polyimide resin having amino groups at both ends is obtained. However, the rubber-modified polyimide resin is further modified with a compound that can be reacted with an amino group, and the block copolymer that has been further modified with a compound that can react with the terminal substituent. Block copolymers are also included in the category of the rubber-modified polyimide resin of the present invention.
In addition, when copolymerizing the aromatic polyimide resin and the aliphatic dicarboxylic acid, an aliphatic dicarboxylic acid having an excess molar ratio with respect to the aromatic polyimide is used to obtain a rubber-modified polyimide resin having carboxyl groups at both ends. However, the rubber-modified polyimide resin is further modified with a compound that can be further reacted with a carboxyl group, and the block copolymer that has been further modified with a compound that can react with the terminal substituent. The block copolymer is also included in the category of the rubber-modified polyimide resin of the present invention.

  That is, the rubber-modified polyimide resin of the present invention has a repeating unit represented by the following formula (1).

In the formula (1), m and n are average repeat numbers, and represent positive numbers satisfying the relationship of 0 <m ≦ 200 and 0 <n ≦ 200. Q ₁ is independently a divalent aromatic group, Q ₂ is independently a tetravalent aromatic group, and R is independently a divalent aliphatic group.
The divalent aromatic group represented by Q _{1 in the} formula (1) is a divalent linking group obtained by removing two amino groups from an aromatic diamine. Specific examples of the aromatic diamine that can be a divalent aromatic group represented by Q ₁ include m-phenylenediamine, p-phenylenediamine, and phenylenediamines such as m-tolylenediamine, 4,4′-diaminodiphenyl ether. 3,3′-dimethyl-4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether and diaminodiphenyl ethers such as 4,4′-diaminodiphenylthioether, 3,3′-dimethyl-4,4′- Diaminodiphenylthioethers such as diaminodiphenylthioether, 3,3′-diethoxy-4,4′-diaminodiphenylthioether, 3,3′-diaminodiphenylthioether and 3,3′-dimethoxy-4,4′-diaminodiphenylthioether 4,4'-diaminobenzophenone comparable Diaminobenzophenones such as 3,3′-dimethyl-4,4′-diaminobenzophenone, diaminodiphenyl sulfones such as 4,4′-diaminodiphenyl sulfoxide and 4,4′-diaminodiphenyl sulfone, benzidine, Bendidines such as 3,3′-dimethylbenzidine and 3,3′-dimethoxybenzidine; diaminobiphenyls such as 3,3′-diaminobiphenyl, p-xylylenediamine, m-xylylenediamine and o- Xylylenediamines such as xylylenediamine, diaminodiphenylmethanes such as 4,4′-diaminodiphenylmethane, 3,7-diamino-2,8-dimethyl-dibenzothiophene, 2,8-diamino-3,7-dimethyl- Dibenzothiophene, 3,7-diamino-2,6-dimethyl-dibenzo Offene and diamino-dibenzothiophenes such as 3,7-diamino-2,8-diethyl-dibenzothiophene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, bis [4- (4-amino Phenoxy) phenyl] propane, bis [4- [4-aminophenoxy] phenyl] sulfone, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexa Fluoropropane, 3,3′-bistrifluoromethyl-5,5′-diaminobiphenyl diamine, 4,4′-bis (4-aminotetrafluorophenoxy) tetrafluorobenzene, 4,4′-bis (4-amino) Tetrafluorophenoxy) octafluorobiphenyl, 3,5-diaminobenzotrifluoride, 2,5- Aminobenzotrifluoride, 3,3′-bistrifluoromethyl-4,4′-diaminobiphenyl, 3,3′-bistrifluoromethyl-5,5′-diaminobiphenyl, bis (trifluoromethyl) -4,4 ′ Examples include diamines such as -diaminodiphenyl, 4,4'-bis (4-aminotetrafluorophenoxy) tetrafluorobenzene, and 4,4'-bis (4-aminotetrafluorophenoxy) octafluorobiphenyl.

The tetravalent aromatic group represented by Q _{2 in the} formula (1) is a tetravalent linking group obtained by removing four carboxyl groups from the hydrate of aromatic tetracarboxylic dianhydride. Specific examples of the tetracarboxylic dianhydride that can be a tetravalent aromatic group represented by Q ₂ include 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA), 3,3. ', 4,4'-Benzophenone tetracarboxylic dianhydride (BTDA), 3,3', 4,4'-biphenyl ether tetracarboxylic dianhydride (OPDA), 3,3 ', 4 4′-diphenylsulfonetetracarboxylic dianhydride (DSDA), bicyclo (2,2,2) -oct-7ene-2,3,5,6-tetracarboxylic dianhydride (BCD), 1, 2,4,5-cyclohexanetetracarboxylic dianhydride (H-PMDA), pyromellitic dianhydride (PMDA), 2,2-bis (3,4-dicarbonoxyphenyl) hexafluoropropane Dianhydrides (6FDA) and 5- (2,5-di Kiso-tetrahydrofuryl) -3-methyl-3-cyclo-hexene-1,2-dicarboxylic acid anhydride (CP), and the like.

The divalent aliphatic group represented by R in the formula (1) is a divalent linking group obtained by removing two carboxyl groups from an aliphatic dicarboxylic acid. The aliphatic dicarboxylic acid that can be a divalent aliphatic group represented by R is not particularly limited as long as it is an aliphatic resin having an aliphatic chain as a main chain and having carboxyl groups at both ends. The hydrogen atom in the main chain of the aliphatic resin may be substituted with a substituent, and the main chain may be modified, but the butadiene-acrylonitrile copolymer, butadiene copolymer, hydrogenated butadiene-acrylonitrile copolymer An aliphatic resin having a polymer or hydrogenated butadiene copolymer as the main chain is preferred. The number average molecular weight of these aliphatic resins is usually 200 to 10,000, preferably 500 to 5,000.
As a specific example of a commercially available product of an aliphatic dicarboxylic acid that can be a divalent aliphatic group represented by R in the formula (1), HYPRO CTBN 1300 × 8 (glass transition point: −52 ° C.) manufactured by CVC Thermoset Specialist, HYPRO CTBN 1300X31 (glass transition point: -66 ° C), HYPRO CTBN 1300X13 (glass transition point: -39 ° C), and the like.

Aromatic diamine compounds having a partial structure Q _1, the partial structure Q aromatic tetracarboxylic acid dianhydride with ₂ and partial building block at both ends is an amino group or a carboxyl group derived from only aliphatic dicarboxylic acid co with R The compound that can further modify the polymer is not particularly limited as long as it is a compound having a substituent such as a glycidyl ether group or an isocyanate group capable of reacting with an amino group or a carboxyl group, and a compound having the above substituent The compound that can further modify the block copolymer further modified in (1) is not particularly limited as long as it is a compound that can react with a substituent at the terminal of the further modified block copolymer.
The scope of the rubber-modified polyimide resin of the present invention, aliphatic dicarboxylic acids having aromatic diamine compound having the following partial structure to Q ₁ above, the aromatic tetracarboxylic acid dianhydride having a partial structure Q ₂ and the partial structure R not only block copolymer obtained from only, but the block copolymer is included more block copolymers that are organized in various compounds, as the rubber-modified polyamide resin of the present invention, having the partial structure Q ₁ aromatic diamine compounds, an aromatic tetracarboxylic dianhydride and the partial structure block copolymer obtained only from aliphatic dicarboxylic acids having R having the partial structure Q _2, i.e., the following formula (1-1) or (1 -2) is more preferable.

Equation (1-1) and formula (1-2), m, _n, Q 1, _{Q 2} and R represents m, _n, the same meaning as Q 1, _{Q 2} and R in the formula (1).

Next, a method for producing the rubber-modified polyimide resin of the present invention will be described.
The rubber-modified polyimide resin of the present invention is a block copolymer of an aromatic polyimide resin having amino groups at both ends, which is a condensate of aromatic tetracarboxylic dianhydrides and aromatic diamines, and an aliphatic dicarboxylic acid. It is a coalescence.
Specifically, first, an aromatic polyimide resin having amino groups at both ends is synthesized, and an aliphatic resin having carboxyl groups at both ends is added to a resin solution cooled to 110 ° C. or lower after the synthesis. The block copolymer in the present invention can be obtained by performing a condensation reaction between the end of the resin and the end of the aliphatic resin. The block copolymer may be purified according to a conventional method.

To make both ends of the aromatic polyimide resin, which is a condensate of aromatic tetracarboxylic dianhydrides and aromatic diamines, with amino groups, the total number of moles of aromatic tetracarboxylic dianhydrides On the other hand, the condensation reaction is carried out using an excess of aromatic diamines having a total molar number. In this case, the closer the total number of moles of aromatic tetracarboxylic dianhydrides and the total number of moles of aromatic diamines, the longer the aromatic polyimide resin having a larger weight average molecular weight, and the aromatic tetracarboxylic dianhydride. The shorter the total number of moles of the aromatics and the total number of moles of the aromatic diamines, the shorter the weight average molecular weight of the short-chain aromatic polyimide resin (Flory rule in the condensation polymer polymerization reaction).
The condensation reaction between the aromatic tetracarboxylic dianhydrides and the aromatic diamines may be performed by a conventionally known method.

  The weight average molecular weight of the aromatic polyimide resin is preferably 5,000 to 200,000, and more preferably 20,000 to 60,000. When the weight average molecular weight is less than 5,000, the toughness of the film is deteriorated and the film cannot be formed. When the weight average molecular weight is larger than 200,000, the solvent solubility of the block copolymer is deteriorated and film formation is impossible. In addition, the weight average molecular weight in this invention means the weight average molecular weight computed in polystyrene conversion based on the measurement result of GPC.

The rubber-modified polyimide resin of the present invention is a condensate of the above-described aromatic polyimide resin having amino groups at both ends and an aliphatic resin having carboxylic acid groups at both ends. -342366 can be synthesized according to the method described in the publication.
That is, in the rubber-modified polyimide resin represented by the above formula (1-1), both ends of the aliphatic dicarboxylic acid, which is a condensate of an aromatic tetracarboxylic dianhydride and an aromatic diamine compound, are amino. Is a block copolymer obtained by using an excessive number of moles of aromatic polyimide resin, and the rubber-modified polyimide resin represented by the above formula (1-2) is composed of aromatic tetracarboxylic dianhydride and aromatic It is a block copolymer obtained by using an aliphatic dicarboxylic acid in an excessive number of moles relative to an aromatic polyimide resin having amino groups at both ends, which is a condensate with a diamine compound.

  A conventionally well-known thing can be used for the condensing agent at the time of condensing the aliphatic resin which has a carboxyl group at both ends with the aromatic polyimide resin which has an amino group at both ends. Specific examples of the condensing agent include dicyclohexylcarbodiimide, carbonyldiimidazole, ethyl (hydroxyimino) cyanoacetate, hydroxybenzotriazole and the like.

The rubber-modified polyimide resin is produced by first synthesizing an aromatic polyimide resin having amino groups at both ends and then condensing a fatty dicarboxylic acid with the terminal amino group. A method of synthesizing a polyamic acid from anhydrides and aromatic diamines and then obtaining a condensate of the polyamic acid and an aliphatic dicarboxylic acid, followed by a ring-closing reaction (imidization) may be used.
However, aromatic polyimide resins require a high temperature of 350 ° C. or higher when no catalyst is used during the ring-closing reaction, and even when a catalyst is used, a high temperature of at least 170 ° C. is required. Therefore, the aliphatic resin deteriorates during the ring-closing reaction. There is a risk. Therefore, a synthesis method in which after completing the ring-closure reaction of the aromatic polyimide resin and cooling to 110 ° C. or lower, an aliphatic resin is added and condensed is more preferable.

The rubber-modified polyimide resin of the present invention has an effect that it is excellent in solubility in an organic solvent. Therefore, it is a preferable aspect to use for various uses as a polyimide resin solution dissolved in an organic solvent.
The organic solvent that can be used in the polyimide resin solution of the present invention is not particularly limited. For example, lactones such as γ-butyrolactone and γ-valerolactone, N-methylpyrrolidone (NMP), N, N-dimethylformamide (DMF), N Amide solvents such as N, N-dimethylacetamide, N, N-dimethylimidazolidinone, sulfones such as tetramethylene sulfone, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether monoacetate, Ether solvents such as propylene glycol monobutyl ether, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, Examples include aromatic solvents such as toluene and xylene.

Among these, by using an organic solvent having a relatively low boiling point such as methyl ethyl ketone or toluene, the rubber-modified polyimide resin of the present invention having excellent heat resistance can be used in various applications at a process of 170 ° C. or lower.
The content of the rubber-modified polyimide in the polyimide resin solution is usually 5 to 90% by mass, preferably 10 to 80% by mass.

When the rubber-modified polyimide resin of the present invention has a reactive substituent (for example, amino group or carboxyl group) at the terminal, it can be used as a polyimide resin composition in which a compound capable of reacting with the polyimide resin is used in combination. In the case where the end of the rubber-modified polyimide resin of the present invention is further modified with a compound capable of reacting with an amino group or a carboxyl group, and the modified site has a reactive substituent. Can also be used as a polyimide resin composition in combination with a compound capable of reacting with the reactive substituent at the modified site.
The compound that can be used in combination with the rubber-modified polyimide resin is not particularly limited as long as it is a compound that can react with a reactive substituent at the terminal (or modified site), but a polyfunctional epoxy resin should be used in combination. Is preferred. By reacting the reactive substituent which the rubber-modified polyimide resin has at the terminal (or modified site) with the polyfunctional epoxy resin, the effect of improving the mechanical strength and solvent resistance of the cured product can be expected.
The polyfunctional epoxy resin that can be used in combination with the rubber-modified polyimide resin in the polyimide resin composition is preferably one containing an aromatic ring. More specifically, an epoxy resin having an aromatic ring such as a benzene ring, a biphenyl ring or a naphthalene ring and having two or more epoxy groups in one molecule is preferable. Specific examples of the polyfunctional epoxy resin satisfying the above conditions include novolak type epoxy resin, xylylene skeleton-containing phenol novolak type epoxy resin, biphenyl skeleton containing novolak type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, tetra Examples thereof include, but are not limited to, methyl biphenol type epoxy resins.

  The amount of the compound capable of reacting with the rubber-modified polyimide resin in the polyimide resin composition is not particularly limited, but usually the reactive group that the rubber-modified polyimide resin has at the terminal (or modified site) reacts with the rubber-modified polyimide resin. The reactive group possessed by the compound which can be used is equivalent to one or a small excess equivalent.

It is preferable to use a curing accelerator in the polyimide resin composition in order to quickly carry out a crosslinking reaction.
For example, specific examples of the curing accelerator in the case of using an epoxy resin together include 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl. Imidazoles such as -4-methyl-5-hydroxymethylimidazole, tertiary amines such as 2- (dimethylaminomethyl) phenol and 1,8-diaza-bicyclo (5,4,0) undecene-7 And phosphines such as triphenylphosphine, and metal compounds such as tin octylate.
For example, when an epoxy resin is used in combination, the curing accelerator is preferably 10 parts by mass or less, more preferably 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the epoxy resin as necessary.

An organic solvent may be used in combination with the polyimide resin composition.
The organic solvent that can be used in combination is not particularly limited, and examples thereof include the same organic solvents that can be used in the above-described polyimide resin solution. However, it is preferable to use an organic solvent having a boiling point of 140 ° C. or lower. More preferably, an organic solvent having a boiling point of 110 ° C. or lower is used in combination.
The content of the organic solvent in the polyimide resin composition is preferably 90% by mass or less, more preferably 10 to 80% by mass in the polyimide resin composition.

  The homogenous coating film or film of the rubber-modified polyimide resin or polyimide resin composition of the present invention can be obtained, for example, by applying the polyimide resin solution or the polyimide resin composition containing the organic solvent of the present invention to a substrate such as glass on a spin coater or applicator. Etc., and after evaporating the solvent by heating in a dry gas such as air, nitrogen or argon, if a polyimide resin composition is used, it is further cured by heating and then peeled off from the substrate. Can be obtained. The thickness of the homogeneous film thus obtained is preferably 5 μm to 1 mm, and more preferably 10 to 200 μm.

EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to these Examples. In addition, “parts” in the description in the examples means parts by mass.
In addition, the weight average molecular weight in an Example measured the molecular weight using the solvent which added the lithium bromide of the density | concentration of 0.5M to the NMP solvent by the gel permeation chromatography (GPC) method, and created it with standard polystyrene. This is a value calculated from a calibration curve.

Example 1 (Synthesis of rubber-modified polyimide resin of the present invention)
To a glass reactor equipped with a thermometer, a reflux condenser, a Dean-Stark tube, a dropping funnel, a nitrogen introducing device and a stirring device, APB-N (1,3-bis (3-aminophenoxy) benzene, manufactured by Mitsui Chemicals, While charging 5.85 parts of molecular weight 292.33) and 5.96 parts of ODPA (3,3 ′, 4,4′-diphenyl ether tetracarboxylic dianhydride, Manac, molecular weight 310.22), flowing dry nitrogen 135 parts of N-methyl-2-pyrrolidone, 10 parts of toluene and 1 part of pyridine were added and stirred. The reaction was carried out at 180 ° C. for 2 hours while removing water produced by the reaction, and then the flow rate of dry nitrogen was increased and toluene in the system was extracted from the Dean-Stark tube. After the reactor was cooled to 95 ° C., 10 parts of triphenyl phosphite and 5 parts of pyridine were added while continuing stirring at the same temperature, and then a carboxyl-terminated butadiene-acrylonitrile copolymer (HYPRO CTBN 1300 × 8 CVC thermo). The total amount of a solution obtained by dissolving 12 parts of N-methyl-2-pyrrolidone in 12 parts of N-methyl-2-pyrrolidone was added dropwise over 30 minutes. After completion of dropping, the reaction was further carried out at 95 ° C. for 2 hours to obtain a solution containing a block copolymer of an aromatic polyimide resin and an aliphatic resin (rubber-modified polyimide resin of the present invention).
After cooling this reaction liquid to room temperature, it was diluted with 50 parts of methanol and then added dropwise to 500 parts of ion-exchanged water, and the precipitated powder was collected by filtration. The powder was boiled with ion-exchanged water and filtered four times, and then dried in an oven at 70 ° C. to obtain 19.3 parts of powder of the rubber-modified polyimide resin (polyimide resin 1) of the present invention. . The weight average molecular weight of this resin powder was 52,200.

Example 2 (Synthesis of rubber-modified polyimide resin of the present invention)
To a glass reactor equipped with a thermometer, a reflux condenser, a Dean-Stark tube, a dropping funnel, a nitrogen introducing device and a stirring device, APB-N (1,3-bis (3-aminophenoxy) benzene, manufactured by Mitsui Chemicals, While charging 5.85 parts of molecular weight 292.33) and 5.74 parts of ODPA (3,3 ′, 4,4′-diphenyl ether tetracarboxylic dianhydride, Manac, molecular weight 310.22), flowing dry nitrogen 134 parts of N-methyl-2-pyrrolidone, 10 parts of toluene and 1 part of pyridine were added and stirred. The reaction was carried out at 180 ° C. for 2 hours while removing water produced by the reaction, and then the flow rate of dry nitrogen was increased, and toluene in the system was extracted from the Dean-Stark tube. After the reactor was cooled to 95 ° C., 10 parts of triphenyl phosphite and 5 parts of pyridine were added while continuing stirring at the same temperature, and then a carboxyl-terminated butadiene-acrylonitrile copolymer (HYPRO CTBN 1300 × 8 CVC thermo). The total amount of a solution obtained by dissolving 12 parts of N-methyl-2-pyrrolidone in 12 parts of N-methyl-2-pyrrolidone was added dropwise over 30 minutes. After completion of dropping, the reaction was further carried out at 95 ° C. for 2 hours to obtain a solution containing a block copolymer of an aromatic polyimide resin and an aliphatic resin (rubber-modified polyimide resin of the present invention).
After cooling this reaction liquid to room temperature, it was diluted with 50 parts of methanol and then added dropwise to 500 parts of ion-exchanged water, and the precipitated powder was collected by filtration. The powder was boiled with ion-exchanged water and filtered four times, and then dried in an oven at 70 ° C. to obtain 21.1 parts of powder of rubber-modified polyimide resin (polyimide resin 2) of the present invention. . The weight average molecular weight of this resin powder was 47,800.

Comparative Example 1 (Synthesis of polyimide resin for comparison)
To a glass reactor equipped with a thermometer, a reflux condenser, a Dean-Stark tube, a dropping funnel, a nitrogen introducing device and a stirring device, APB-N (1,3-bis (3-aminophenoxy) benzene, manufactured by Mitsui Chemicals, Molecular weight 292.3) 302.23 parts and ABPS (3,3'-diamino-4,4'-hydroxy-diphenylsulfone, Nippon Kayaku, molecular weight 280.3) 4.97 parts, N-methyl-2- After charging 1296 parts of pyrrolidone (NMP), stirring and dissolving at 70 ° C., ODPA (3,3 ′, 4,4′-diphenyl ether tetracarboxylic dianhydride, Manac, molecular weight 310.22) 313.7 Then, 68.2 parts of NMP, 198 parts of toluene and 16 parts of pyridine were added and stirred while flowing dry nitrogen. The reaction was carried out at 180 ° C. for 2 hours while removing the water produced by the reaction, and then the flow rate of dry nitrogen was increased to extract toluene in the system from the Dean-Stark tube. The solvent was recovered under reduced pressure to obtain a polyimide resin solution having a solid content of 28%. After diluting 15 parts of this polyimide resin solution with N, N-dimethylformamide and acetone, it was dropped into ion exchange water to precipitate a powdery resin. The precipitated powder was collected by filtration, boiled with ion-exchanged water and then filtered four times, followed by drying in an oven at 70 ° C. to obtain 4 parts of a comparative polyimide resin (polyimide resin 3) powder. It was. The weight average molecular weight of this resin powder was 58,800.

Comparative Example 2 (Synthesis of rubber-modified aramid resin for comparison)
A glass reactor equipped with a thermometer, a reflux condenser, a Dean-Stark tube, a dropping funnel, a nitrogen introducing device, and a stirring device was added to 3,4′-ODA (3,4′-oxydianiline, Seika, molecular weight 200). .24) 79.8 parts, 50.6 parts of isophthalic acid, 9.3 parts of 5-hydroxyisophthalic acid, and 7.6 parts of lithium chloride, and N-methyl-2-pyrrolidone (NMP) while flowing dry nitrogen 897 parts and 90 parts of pyridine were added and stirred. After dissolving at 95 ° C., 195 parts of triphenyl phosphite was added dropwise and stirred at 95 ° C. for 2 hours.
Next, the reactor was kept at 95 ° C., and a total amount of a solution in which 126 parts of a carboxyl-terminated butadiene / acrylonitrile copolymer (carboxyl equivalent = 0.052EPHR manufactured by HYPRO CTBN 1300X8 CVC Thermoset Specialist) was dissolved in 126 parts of NMP in 1 hour. The solution was added dropwise and stirred for another 2 hours.
Thereafter, the inside of the reactor was cooled to 70 ° C. or lower, and ion-exchanged water was dropped to deposit a powdery resin. The precipitated powder was collected by filtration, boiled with ion-exchanged water and then filtered four times, and then dried in an oven at 70 ° C. to obtain 246 parts of a comparative aramid resin (aramid resin 1) powder. It was. The weight average molecular weight of this resin powder was 96,700.

Comparative Example 3 (synthesis of comparative aramid resin)
A glass reactor equipped with a thermometer, a reflux condenser, a Dean-Stark tube, a dropping funnel, a nitrogen introducing device, and a stirring device was added to 3,4′-ODA (3,4′-oxydianiline, Seika, molecular weight 200). .24) 163.4 parts, 130.25 parts isophthalic acid, and 2.91 parts 5-hydroxyisophthalic acid, 439 parts N-methyl-2-pyrrolidone (NMP) and 94.5 pyridine while flowing dry nitrogen Part was added and stirred. After dissolving at 90 ° C., 409.6 parts of triphenyl phosphite was added dropwise and stirred at 90 ° C. for 6 hours.
The reaction solution was dropped seven times with ion-exchanged water and the resin was precipitated and drained, and then diluted with 800 parts of γ-butyrolactone and dehydrated under reduced pressure to give 720 aramid resin solution having a solid content of 27%. I got a part. After diluting 15 parts of this aramid resin solution with N, N-dimethylformamide and acetone, the resin in a powder form was precipitated by adding dropwise to ion exchange water. The precipitated powder was collected by filtration, boiled with ion-exchanged water and then filtered four times, and then dried in an oven at 70 ° C. to obtain 4 parts of a comparative aramid resin (aramid resin 2) powder. It was. The weight average molecular weight of the resin contained in this solution was 94,900.

Examples 3 and 4 and Comparative Examples 4 to 6
(Solubility test)
Each resin obtained in Examples 1 and 2 and Comparative Examples 1 to 3 and each organic solvent described in Table 1 in an amount such that the resin concentration is 5% by mass are weighed into a glass bottle with a lid, and TUBE MIXER TRIO TM- Using 1F (manufactured by ASONE), after 5 minutes of shaking, the appearance after heat treatment in a 70 ° C. oven for 3 hours was visually observed, and the solubility of each resin in an organic solvent was evaluated according to the following evaluation criteria. The results are shown in Table 1.
Evaluation criteria 1; Transparent uniform solution, fluidity 2; Opaque uniform solution, fluidity 3; Swelled resin and solvent separated, resin fluidity 4; Swelled resin and solvent separated, resin No fluidity 5; Non-swelled resin and solvent separated, no resin fluidity

(Heat resistance evaluation)
Each resin obtained in Examples 1 and 2 and Comparative Examples 1 to 3 was dissolved in cyclopentanone to prepare each resin solution having a resin concentration of 30% by mass, and applied to a release PET film. Dry in oven for 10 minutes. The resin film was peeled off from the release PET film, fixed to a metal frame, and dried again in an inert oven at 170 ° C. for 30 minutes to obtain each resin film having a thickness of 10 to 30 μm.
A test piece of 20 mm × 5 mm × 15 μm was cut out from each of the obtained resin films, and using a dynamic viscoelasticity measuring device (DMA), a tensile mode, a distance between chucks of 10 mm, a measurement temperature of 25 to 280 ° C., and a heating rate of 5 The glass transition point was measured under the conditions of ° C / min and a measurement frequency of 1 Hz. The results are shown in Table 1.

  If the evaluation result of the solubility test is 1 or 2, it is a fluid uniform solution, so it can be used as a film as it is or in a coating process, so it can be applied to various applications. .

The rubber-modified polyimide resin of the present invention is soluble in a solvent having a low boiling point such as methyl ethyl ketone and toluene while having a high heat resistance with a glass transition point of 170 ° C. or higher. Therefore, the low boiling point solvent solution of the polyimide resin can be used for various applications in a low temperature treatment process of 170 ° C. or lower.

Claims (5)

Following formula (1)

(In the formula (1), m and n are average repeat numbers and represent positive numbers satisfying the relationship of 0 <m ≦ 200 and 0 <n ≦ 200. Q ₁ is independently a divalent aromatic group. Wherein Q ₂ is independently a tetravalent aromatic group, and R is each independently a divalent aliphatic group.) A rubber-modified polyimide resin having a repeating unit represented by: Following formula (1-1) or (1-2)

(In the formula (1-1) and the formula _{(1-2), m, n,} Q 1, Q 2 and R m in the formula (1) according to claim _{1, n, Q 1, Q} 2 and R The rubber-modified polyimide resin according to claim 1, which has the same meaning as A polyimide resin solution comprising the rubber-modified polyimide resin according to claim 1 or 2 and an organic solvent. The polyimide resin solution according to claim 3, comprising an organic solvent having a boiling point of 140 ° C. or lower. The polyimide resin solution according to claim 4, wherein the organic solvent contains at least one of methyl ethyl ketone and toluene.