JP2008001791A - Soluble terminal-modified amic acid silyl ester oligomers and varnishes and cured products thereof - Google Patents

Abstract

（式中、Ｒ_１は２価の芳香族ジアミン残基を、Ｒ_２は４価の芳香族テトラカルボン酸類残基を、Ｒ_３は１価の有機ケイ素基を表し、ｎは１≦ｎ≦２０の関係を満たす。）
【選択図】なし[PROBLEMS] A novel terminal modification having excellent solubility in low-boiling organic solvents other than amide solvents and moldability such as low melt viscosity, and high mechanical properties such as heat resistance and elastic modulus, tensile strength and elongation of cured products. Amidic acid silyl ester oligomers and varnishes and terminal-modified imide oligomers and cured products thereof are provided.
The soluble terminal-modified amic acid silyl ester oligomer of the present invention is represented by the general formula (1).

(In the formula, R ₁ represents a divalent aromatic diamine residue, R ₂ represents a tetravalent aromatic tetracarboxylic acid residue, R ₃ represents a monovalent organosilicon group, and n represents 1 ≦ n ≦ Satisfies 20 relationships.)
[Selection figure] None

Description

  The present invention relates to a terminal-modified imide oligomer used in a wide field where high heat resistance is required including aircraft and space industry equipment, a terminal-modified amic acid silyl ester oligomer as a precursor thereof, and a cured product thereof.

Aromatic polyimide is used in a wide range of fields because it has the highest level of heat resistance in a polymer material system and has excellent mechanical and electrical characteristics.
On the other hand, aromatic polyimide is generally poor in processability, and is not particularly suitable for use as a matrix resin for melt molding or fiber reinforced composite materials. For this reason, an imide oligomer having a terminal modified with a thermal crosslinking group has been proposed. Among them, an imide oligomer having a terminal modified with 4- (2-phenylethynyl) phthalic anhydride is considered to have an excellent balance of moldability, heat resistance, and mechanical properties. For example, Patent Document 1, Patent Document 2, and Non-Patent Document It is introduced in Patent Document 1 and Non-Patent Document 2. Patent Document 1 aims to provide a terminal-modified imide oligomer having excellent heat resistance and mechanical properties of the cured product and high practicality, and 2,3,3 ′, 4′-biphenyl. End-modified imide oligomer obtained by reacting tetracarboxylic dianhydride, aromatic diamine compound and 4- (2-phenylethynyl) phthalic anhydride, having a logarithmic viscosity of 0.05 to 1 dL / g and its curing Things are disclosed. As an effect of the invention, a novel terminal-modified imide oligomer having high practicality can be obtained, and a novel terminal-modified imide oligomer having excellent mechanical properties such as heat resistance, elastic modulus, tensile strength and elongation. It is described that a cured product can be obtained.

However, these terminal-modified imide oligomers are in an organic solvent such as N-methyl-2-pyrrolidone (hereinafter abbreviated as NMP) at room temperature (herein, room temperature means 23 ° C. ± 2 ° C.). Only 20% by mass or less can be dissolved, and if this varnish is stored, a phenomenon of gelation is often observed after several days, and it is difficult to stably store a high concentration varnish for a long period of time. ing. Therefore, instead of the terminal-modified imide oligomer, a solution of a terminal-modified amic acid oligomer that is a soluble precursor is used, but the terminal-modified amic acid oligomer is NMP (boiling point 202 ° C.) or N, N-dimethylacetamide (DMAc). ) (Boiling point 165 ° C.). Furthermore, it is known that an amic acid oligomer forms a complex with an amide solvent such as NMP or DMAc, and the solvent continues to evaporate until imidization is completed even when heated to a boiling point or higher specific to the solvent. In this way, the amide acid oligomer contains an amide-based high-boiling solvent that is difficult to remove, so that the residual solvent volatilizes during heat curing and voids are formed in the molded product, or the temperature is increased while containing the solvent. There exists a problem that a viscosity falls rapidly and resin flows out.
Japanese Patent No. 3551846 Special table 2003-526704 gazette PM Hergenrother and JG Smith Jr., Polymer, 35, 4857 (1994). R. Yokota, S. Yamamoto, S. Yano, T. Sawaguchi, M. Hasegawa, H. Yamaguchi, H. Ozawa and R. Sato, High Perform. Polym., 13, S61 (2001).

As one of the methods for synthesizing polyimide used as a thin film, for example, as in Non-Patent Document 3 and Patent Document 3, a ring-opening polyaddition reaction of N, N′-disilylated diamine and tetracarboxylic dianhydride, or diamine, A method is known in which a polyamic acid silyl ester is first produced by a reaction with a silylating agent and tetracarboxylic dianhydride and then cyclized by heat treatment to obtain a polyimide with elimination of silanol. This polyamic acid silyl ester, which is a precursor of this polyimide, has high solubility and is also soluble in non-amide low-boiling solvents such as tetrahydrofuran. However, it is difficult to form a thick plate and it is limited to thin film applications. In thin film production, the removal of the solvent is easy even with a high boiling point solvent, so the advantage that the polyamic acid silyl ester is soluble in the low boiling point solvent is not great. .
Y. Oishi, M. Kakimoto and Y. Imai, Macromolecules, 24, 3475 (1991). JP 2002-322275 A

  Thick plates and fiber reinforced composite materials are required for materials that can be used in a wide range of fields that require easy moldability and high heat resistance such as aircraft and space industry equipment. When the solvent is used, it is difficult to completely remove the solvent, so that the residual solvent volatilizes during heat curing and voids are formed in the molded body, or the viscosity rapidly decreases when the temperature is increased while containing the solvent. There is a problem that the resin flows out. Therefore, a terminal-modified imide oligomer precursor that is soluble in a low-boiling non-amide solvent is required in order to prevent void generation and resin outflow.

  The present invention is excellent in moldability such as solubility in low-boiling organic solvents other than amide-based high-boiling solvents and low melt viscosity, and has high mechanical properties such as heat resistance and elastic modulus, tensile strength and elongation of cured products. It is an object to provide a terminal-modified amic acid silyl ester oligomer and varnish, a terminal-modified imide oligomer, and a cured product thereof.

（式中、Ｒ_１は２価の芳香族ジアミン残基を、Ｒ_２は４価の芳香族テトラカルボン酸類残基を、Ｒ_３は式２で表される１価の有機ケイ素基を表し、ｎは１≦ｎ≦２０の関係を満たす。）

（式中、Ｒ_４、Ｒ_５、Ｒ_６はそれぞれ独立して炭素数１〜４のアルキル基または１価の芳香族基を表す。） The present invention provides an oligomer represented by the general formula (1) as a novel terminal-modified amic acid silyl ester oligomer.

(Wherein R ₁ represents a divalent aromatic diamine residue, R ₂ represents a tetravalent aromatic tetracarboxylic acid residue, R ₃ represents a monovalent organosilicon group represented by Formula 2, n satisfies the relationship 1 ≦ n ≦ 20.)

(Wherein _represents R _4, R 5, _{R 6} each independently represents an alkyl group or a monovalent aromatic group having 1 to 4 carbon atoms.)

Moreover, this invention provides the varnish containing the terminal modified amidic acid silyl ester oligomer represented by Formula (1).
In addition, the present invention provides a terminal-modified amide silyl ester oligomer represented by formula (1) or a terminal-modified imide oligomer obtained by heating the varnish and a cured product thereof.

  According to the present invention, it is excellent in moldability such as solubility in low-boiling organic solvents other than amide-based high-boiling solvents, low melt viscosity, and high mechanical properties such as heat resistance and elastic modulus, tensile strength and elongation of cured products. Terminal-modified amic acid silyl ester oligomers and varnishes, terminal-modified imide oligomers and cured products thereof can be obtained.

  The terminal-modified amidic acid silyl ester oligomer represented by the general formula (1) of the present invention is a solution obtained by reacting an aromatic diamine with an silylating agent in an amount equivalent to the amino group equivalent of the aromatic diamine. And an aromatic tetracarboxylic acid compound and phenylethynyl phthalic anhydride such as 4- (2-phenylethynyl) phthalic anhydride (hereinafter sometimes abbreviated as PEPA), and the total equivalent amount of each acid group An amic acid silyl ester oligomer obtained by reacting in a solvent such that the equivalent amount of amino group is approximately equivalent, and the terminal (preferably both terminals) of the amic acid silyl ester oligomer An acetylenic addition-curable unsaturated end group based on 4- (2-phenylethynyl) phthalic anhydride and an amide in the main chain of the amide silyl ester oligomer The case and side chain having a silyl ester bond, preferably terminal-modified amic acid silyl ester oligomer is a relatively low molecular weight which satisfies the relationship of 1 ≦ n ≦ 20. Further, a terminal-modified amic acid that can be dissolved in an organic solvent other than an amide solvent such as 2-butanone, tetrahydrofuran, cyclohexanone, 1,4-dioxane, and 2-methoxyethyl acetate at room temperature in a solid content range of 20 to 50% by mass. Silyl ester oligomers are preferred. Furthermore, a terminal-modified amic acid silyl ester oligomer having a glass transition temperature (Tg) after curing of the oligomer of 250 ° C. or higher is preferred.

  Examples of the aromatic diamine compound include 1,4-diaminobenzene, 1,3-diaminobenzene, 1,2-diaminobenzene, 2,6-diethyl-1,3-diaminobenzene, 4,6-diethyl- 2-methyl-1,3-diaminobenzene, 3,5-diethyl-2,6-diaminotoluene, 4,4′-diaminodiphenyl ether (4,4′-ODA), 3,4′-diaminodiphenyl ether (3,3) 4′-ODA), 3,3′-diaminodiphenyl ether, 3,3′-diaminobenzophenone, 4,4′-diaminobenzophenone, 3,3′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, bis (2, 6-diethyl-4-aminophenyl) methane, 4,4′-methylene-bis (2,6-diethylaniline), bi (2-ethyl-6-methyl-4-aminophenyl) methane, 4,4′-methylene-bis (2-ethyl-6-methylaniline), 2,2-bis (3-aminophenyl) propane, 2, 2-bis (4-aminophenyl) propane, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, benzidine, 3,3′-dimethylbenzidine, 2,2-bis (4-aminophenoxy) propane, 2,2-bis (3-aminophenoxy) propane, 2 , 2-bis [4 ′-(4 ″ -aminophenoxy) phenyl] hexafluoropropane, 9,9-bis (4-aminophenyl) fluorene, 9,9-bis [4 (4-aminophenoxy) phenyl] fluorene, and the like, can be used in combination thereof alone, or two or more. In particular, as aromatic diamine compounds, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 1,3-bis (4-aminophenoxy) benzene, or 9,9-bis [4- (4-amino Phenoxy) phenyl] fluorene is preferred.

  Examples of the aromatic tetracarboxylic acid compound include 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3 ′, 4′-biphenyltetracarboxylic acid 2 Anhydride (a-BPDA), 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride (i-BPDA), 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride (BTDA) ), Pyromellitic dianhydride (PMDA), bis (3,4-dicarboxyphenyl) methane dianhydride, bis (3,4-carboxyphenyl) ether dianhydride, and their tetracarboxylic acids or tetra Derivatives such as esters or salts of carboxylic acids can be mentioned, and these can be used alone or in combination of two or more. In particular, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and 2,3,3', 4'-biphenyltetracarboxylic dianhydride are suitable.

  Examples of the organosilicon group of the terminal-modified amic acid silyl ester oligomer represented by the general formula (1) of the present invention include, for example, a trimethylsilyl group, a dimethylphenylsilyl group, a methyldiphenylsilyl group, a triethylsilyl group, a tripropylsilyl group, Examples thereof include dimethylpropylsilyl group, butyldimethylsilyl group, and butyldiphenylsilyl group.

  Examples of the silylating agent used in the present invention include chlorosilane-based silylating agents such as chlorotrimethylsilane, chlorotriethylsilane, and chlorodimethylphenylsilane, bis (trimethylsilyl) acetamide, trimethylsilylacetamide, trimethylsilyl-N-methylacetamide, and bis (trimethylsilyl). ) Silylamide silylating agents such as trifluoroacetamide, trimethylsilyl trifluoroacetamide, trimethylsilyl-N-methyltrifluoroacetamide, bis (trimethylsilyl) urea, trimethylsilyldiphenylurea and the like. These silylating agents may be used alone or in combination of two or more. In particular, bis (trimethylsilyl) acetamide and bis (trimethylsilyl) trifluoroacetamide are suitable as silylating agents.

  In the present invention, phenylethynyl phthalic anhydride, preferably 4- (2-phenylethynyl) phthalic anhydride is used as the unsaturated acid anhydride for terminal modification (end cap). The phenylethynyl phthalic anhydride is preferably used in a proportion in the range of 3 to 200 mol%, particularly 5 to 150 mol%, based on the total amount of acids.

  Examples of the solvent include ketone solvents such as 2-butanone and cyclohexanone, ether solvents such as 1,4-dioxane and tetrahydrofuran, and ester solvents such as 2-methoxyethyl acetate. These solvents may be used alone or in combination of two or more.

（式中、Ｒ_１は２価の芳香族ジアミン残基を、Ｒ_２は４価の芳香族テトラカルボン酸類残基を、Ｒ_３は式２で表される１価の有機ケイ素基を、Ｘは水素原子またはＲ_３を表すが、少なくとも１つはＲ_３を表し、ｎは１≦ｎ≦２０の関係を満たす。）

（式中、Ｒ_４、Ｒ_５、Ｒ_６はそれぞれ独立して炭素数１〜４のアルキル基または１価の芳香族基を表す。） Hereinafter, an example of the manufacturing method will be described. The synthesis scheme is shown in Formula (3).

(Wherein R ₁ represents a divalent aromatic diamine residue, R ₂ represents a tetravalent aromatic tetracarboxylic acid residue, R ₃ represents a monovalent organosilicon group represented by Formula 2, X Represents a hydrogen atom or R ₃ , at least one represents R ₃ , and n satisfies the relationship 1 ≦ n ≦ 20.)

(Wherein _represents R _4, R 5, _{R 6} each independently represents an alkyl group or a monovalent aromatic group having 1 to 4 carbon atoms.)

  The terminal-modified amic acid silyl ester oligomer of the present invention includes, for example, an aromatic diamine and 0.5 to 3 equivalents, preferably 0.5 to 1 equivalents of a silylating agent with respect to the amino group equivalent of the aromatic diamine. The amino group is silylated by reacting in the above-mentioned organic solvent preferably at a temperature of −20 ° C. to 60 ° C., and an aromatic tetracarboxylic acid compound (especially this acid anhydride) and phenylethynyl phthalic anhydride are added to this solution. The total amount of acid anhydride groups (or adjacent dicarboxylic acid groups) of all the components and the total amount of amino groups are used in an approximately equal amount, and each component is used in the aforementioned solvent at about 100 ° C. or less, particularly Polymerized at a reaction temperature of 80 ° C. or lower, and “oligomer having amide-silyl ester bond” (amidyl silyl ester oligomer or amic acid silyl ester oligomer) in one pot Say) can be obtained.

  Next, the amidic acid silyl ester oligomer is desilanol-cyclized by a method of heating to a high temperature of 140 to 275 ° C., or after hydrolyzing the silyl ester bond with water or alcohol to form an amic acid oligomer, about 0 By dehydration and cyclization by a method of adding an imidizing agent at a temperature of ˜140 ° C., an imide oligomer having a 4- (2-phenylethynyl) phthalic anhydride residue at the terminal can be obtained.

  Furthermore, the cured product can be formed into a film by, for example, applying the above-mentioned terminal-modified amic acid silyl ester oligomer varnish to a support and heating and curing at 280 to 500 ° C. The terminal-modified imide oligomer powder can be filled in a mold such as a mold and heated and pressurized at 280 to 500 ° C. to obtain a cured product.

  As a particularly preferred production method of the terminal-modified amic acid silyl ester oligomer of the present invention, for example, an aromatic diamine is uniformly dissolved or dispersed in the aforementioned solvent, and then a silylating agent is added to the solution to react at 0 ° C. to 40 ° C. Stir at temperature for about 1 to 180 minutes. Aromatic tetracarboxylic dianhydride is added to the reaction solution and dissolved uniformly, and then stirred at a reaction temperature of about 5 to 60 ° C. for about 1 to 240 minutes. Phenylethynyl phthalic anhydride is added to the reaction solution. In addition, a method of obtaining the above-mentioned terminal-modified amic acid silyl ester oligomer by uniformly stirring and reacting at a reaction temperature of about 5 to 60 ° C. for about 1 to 240 minutes can be mentioned. In the above reaction, it is preferable that all or some of the reaction steps are performed in an atmosphere of an inert gas such as nitrogen gas or argon gas or under reduced pressure.

  The terminal-modified amic acid silyl ester oligomer produced as described above can be used as a solution composition (varnish) of the terminal-modified amidic acid silyl ester oligomer as it is or by concentrating or diluting it appropriately. May be. The terminal-modified oligomer of the present invention may be a mixture of different molecular weights. The terminal-modified amic acid silyl ester oligomer of the present invention may be mixed with other soluble amic acid silyl esters.

  The amidic acid silyl ester oligomer is heated at 140 to 275 ° C. for about 10 to 300 minutes to desilanol and cyclize to obtain an imide oligomer having a phenylethynyl phthalic anhydride residue at the terminal.

The cured product of the terminal-modified amic acid silyl ester oligomer of the present invention is prepared by, for example, applying the above-mentioned terminal-modified amic acid silyl ester oligomer varnish to a support and heating at 140 to 275 ° C. for about 10 to 300 minutes. -After cyclization and solvent removal, the film can be cured by heating at 280 to 500 ° C for 5 to 200 minutes. The terminal-modified imide oligomer powder is filled in a mold such as a mold, and a preform is formed by compression molding at 1 to 1000 kg / cm ² at 10 to 280 ° C. for about 1 second to 100 minutes. The preform can be heated at 280 to 500 ° C. for about 10 minutes to 40 hours to obtain a cured product.

The following examples are given to illustrate the invention, but are not intended to limit the invention. The measurement conditions for each characteristic were as follows.
Test method (1) Infrared spectroscopic analysis (IR): Measured using FT / IR7300 type manufactured by JASCO Corporation.
(2) Elemental analysis: Measured using an organic trace element analyzer 2400 manufactured by PerkinElmer.
(3) Molecular weight measurement: It measured in polystyrene conversion using the Tosoh high speed GPC system HLC-8220.
(4) Thermogravimetric analysis: TG / DTA320 type thermogravimetric analyzer (TGA) manufactured by Seiko Instruments Inc. was used and measured at a heating rate of 10 ° C./min in a nitrogen stream.
(5) Glass transition temperature: Measured using a DSC-60 type differential scanning calorimeter (DSC) manufactured by Shimadzu Corporation at a rate of temperature increase of 20 ° C./min under a nitrogen stream.
(6) Tensile test: TENSILON / UTM-II-20 manufactured by Orientec Co., Ltd. was used at room temperature at a tensile speed of 5 mm / min. The specimen shape was a film having a length of 20 mm, a width of 3 mm, and a thickness of 80 to 120 μm.

(Example 1)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and 2-butanone (4 mL) were added, and bis (trimethylsilyl) acetamide (1.017 g, 5 mmol) was added thereto, followed by stirring at room temperature for 2 hours. To this solution, 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, and polymerization reaction was carried out in a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. An oligomer was produced. To this reaction solution, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and reacted at room temperature for 4 hours in a nitrogen stream to be terminally modified to obtain a uniform transparent solution of terminally modified amidic acid silyl ester oligomer. Got. A part of this solution was cast on a glass plate and dried under reduced pressure at 60 ° C. to obtain a powdered oligomer. The logarithmic viscosity was 0.18 dL / g (concentration 0.5 g / dL, measured in NMP at 30 ° C.). This terminal-modified amic acid silyl ester oligomer has the general formula (1), wherein R ₁ is a diphenyl ether group and a fluorenylidene diphenyl ether group (mixing ratio 50:50 mol%), R ₂ is a biphenyl group, and R ₃ is Represents a trimethylsilyl group, n = 4 on average.
IR (KBr, cm ⁻¹ ): 3344, 3060, 2956, 2215, 1656, 1603, 1541, 1498, 1408, 1220, 1169, 1046, 1014, 843
The remaining solution was cast on a glass plate, heated to 60 ° C., 150 ° C., 200 ° C., and 250 ° C. successively and dried under reduced pressure for 1 hour each to obtain a flaky terminal-modified imide oligomer.
IR (KBr, cm ⁻¹ ): 3053, 2212, 1776, 1719, 1614, 1499, 1371, 1236, 1168, 1111, 1081, 876, 826, 737
As is apparent from the IR spectra, 3344cm ^-1, disappeared amide bond derived from ^{1656cm -1, 1776cm -1, 1719cm -1} , 1371cm -1, occurs imide linkages derived from 737cm ^-1.
Elemental analysis: calculated value [calculated as C _218.5 H ₁₂₀ N ₁₀ O _27.5 ] carbon 78.92%, hydrogen 3.64%, nitrogen 4.21%; measured value carbon 78.54%, hydrogen 3.86%, nitrogen 4.46%
Average molecular weight (measured by standard polystyrene conversion using gel permeation chromatography): number average molecular weight 4200, polydispersity 1.5
This terminal-modified imide oligomer was heated at 370 ° C. for 1 hour with a hot press machine to obtain a film-like cured product.
IR (film, cm ⁻¹ ): 3058, 1776, 1718, 1615, 1499, 1371, 1236, 1168, 1081, 876, 827, 737
As is apparent from the IR spectrum of the cured product, the triple bond derived from 2212 cm ⁻¹ has disappeared.
Glass transition temperature (DSC measurement): 328 ° C
5% weight loss temperature (TGA measurement): 558 ° C
Tensile properties of thermosetting film (thickness 87 μm): elastic modulus 2.78 GPa, breaking strength 115 MPa, breaking elongation 10.8%

(Example 2)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and 2-butanone (4 mL) were added, and bis (trimethylsilyl) trifluoroacetamide (1.287 g, 5 mmol) was added thereto, followed by stirring at room temperature for 2 hours. To this solution, 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, and polymerization reaction was carried out in a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. An oligomer was produced. To this reaction solution, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and reacted at room temperature for 4 hours in a nitrogen stream to be terminally modified to obtain a uniform transparent solution of terminally modified amidic acid silyl ester oligomer. Got. A part of this solution was cast on a glass plate and dried under reduced pressure at 60 ° C. to obtain a powdered oligomer. The logarithmic viscosity was 0.18 dL / g (concentration 0.5 g / dL, measured in NMP at 30 ° C.). This terminal-modified amic acid silyl ester oligomer has the general formula (1), wherein R ₁ is a diphenyl ether group and a fluorenylidene diphenyl ether group (mixing ratio 50:50 mol%), R ₂ is a biphenyl group, and R ₃ is Represents a trimethylsilyl group, n = 4 on average.
IR (KBr, cm ⁻¹ ): 3344, 3060, 2956, 2215, 1656, 1603, 1541, 1498, 1408, 1220, 1169, 1046, 1014, 843
The remaining solution was cast on a glass plate, heated to 60 ° C., 150 ° C., 200 ° C., and 250 ° C. successively and dried under reduced pressure for 1 hour each to obtain a flaky terminal-modified imide oligomer.
IR (KBr, cm ⁻¹ ): 3053, 2212, 1776, 1719, 1614, 1499, 1371, 1236, 1168, 1111, 1081, 876, 826, 737
Elemental analysis: calculated value [calculated as C _218.5 H ₁₂₀ N ₁₀ O _27.5 ] carbon 78.92%, hydrogen 3.64%, nitrogen 4.21%; measured value carbon 78.63%, hydrogen 3.79%, nitrogen 4.41%
Average molecular weight (measured by standard polystyrene conversion using gel permeation chromatography): number average molecular weight 4200, polydispersity 1.5
This terminal-modified imide oligomer was heated at 370 ° C. for 1 hour with a hot press machine to obtain a film-like cured product.
IR (film, cm ⁻¹ ): 3058, 1776, 1718, 1615, 1499, 1371, 1236, 1168, 1081, 876, 827, 737
Glass transition temperature (DSC measurement): 328 ° C
5% weight loss temperature (TGA measurement): 559 ° C
Tensile properties of thermosetting film (thickness 88 μm): elastic modulus 2.79 GPa, breaking strength 115 MPa, breaking elongation 10.9%

(Example 3)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and tetrahydrofuran (4 mL) were added, and bis (trimethylsilyl) acetamide (1.017 g, 5 mmol) was added thereto, followed by stirring at room temperature for 2 hours. To this solution, 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, and polymerization reaction was carried out in a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. An oligomer was produced. To this reaction solution, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and reacted at room temperature for 4 hours in a nitrogen stream to be terminally modified to obtain a uniform transparent solution of terminally modified amidic acid silyl ester oligomer. Got. A part of this solution was cast on a glass plate and dried under reduced pressure at 60 ° C. to obtain a powdered oligomer. The logarithmic viscosity was 0.18 dL / g (concentration 0.5 g / dL, measured in NMP at 30 ° C.). This terminal-modified amic acid silyl ester oligomer has the general formula (1), wherein R ₁ is a diphenyl ether group and a fluorenylidene diphenyl ether group (mixing ratio 50:50 mol%), R ₂ is a biphenyl group, and R ₃ is Represents a trimethylsilyl group, n = 4 on average.
IR (KBr, cm ⁻¹ ): 3344, 3060, 2956, 2215, 1656, 1603, 1541, 1498, 1408, 1220, 1169, 1046, 1014, 843
The remaining solution was cast on a glass plate, heated to 60 ° C., 150 ° C., 200 ° C., and 250 ° C. successively and dried under reduced pressure for 1 hour each to obtain a flaky terminal-modified imide oligomer.
IR (KBr, cm ⁻¹ ): 3053, 2212, 1776, 1719, 1614, 1499, 1371, 1236, 1168, 1111, 1081, 876, 826, 737
Elemental analysis: calculated value [calculated as C _218.5 H ₁₂₀ N ₁₀ O _27.5 ] carbon 78.92%, hydrogen 3.64%, nitrogen 4.21%; measured value carbon 78.63%, hydrogen 3.86%, nitrogen 4.48%
Average molecular weight (measured by standard polystyrene conversion using gel permeation chromatography): number average molecular weight 4200, polydispersity 1.5
This terminal-modified imide oligomer was heated at 370 ° C. for 1 hour with a hot press machine to obtain a film-like cured product.
IR (film, cm ⁻¹ ): 3058, 1776, 1718, 1615, 1499, 1371, 1236, 1168, 1081, 876, 827, 737
Glass transition temperature (DSC measurement): 328 ° C
5% weight loss temperature (TGA measurement): 560 ° C.
Tensile properties of thermosetting film (thickness 87 μm): elastic modulus 2.76 GPa, breaking strength 116 MPa, breaking elongation 11.0%

Example 4
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and cyclohexanone (4 mL) were added, and bis (trimethylsilyl) acetamide (1.017 g, 5 mmol) was added thereto, followed by stirring at room temperature for 2 hours. To this solution, 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, and polymerization reaction was carried out in a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. An oligomer was produced. To this reaction solution, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and reacted at room temperature for 4 hours in a nitrogen stream to be terminally modified to obtain a uniform transparent solution of terminally modified amidic acid silyl ester oligomer. Got. A part of this solution was cast on a glass plate and dried under reduced pressure at 60 ° C. to obtain a powdered oligomer. The logarithmic viscosity was 0.17 dL / g (concentration 0.5 g / dL, measured in NMP at 30 ° C.). This terminal-modified amic acid silyl ester oligomer has the general formula (1), wherein R ₁ is a diphenyl ether group and a fluorenylidene diphenyl ether group (mixing ratio 50:50 mol%), R ₂ is a biphenyl group, and R ₃ is Represents a trimethylsilyl group, n = 4 on average.
IR (KBr, cm ⁻¹ ): 3344, 3060, 2956, 2215, 1656, 1603, 1541, 1498, 1408, 1220, 1169, 1046, 1014, 843
The remaining solution was cast on a glass plate, heated to 60 ° C., 150 ° C., 200 ° C., and 250 ° C. successively and dried under reduced pressure for 1 hour each to obtain a flaky terminal-modified imide oligomer.
IR (KBr, cm ⁻¹ ): 3053, 2212, 1776, 1719, 1614, 1499, 1371, 1236, 1168, 1081, 876, 826, 737
Elemental analysis: calculated value [calculated as C _218.5 H ₁₂₀ N ₁₀ O _27.5 ] carbon 78.92%, hydrogen 3.64%, nitrogen 4.21%; measured value carbon 79.06%, hydrogen 3.93%, nitrogen 4.43%
Average molecular weight (measured in terms of standard polystyrene using gel permeation chromatography): number average molecular weight 4100, polydispersity 1.5
This terminal-modified imide oligomer was heated at 370 ° C. for 1 hour with a hot press machine to obtain a film-like cured product.
IR (film, cm ⁻¹ ): 3058, 1776, 1718, 1615, 1499, 1371, 1236, 1168, 1081, 876, 827, 737
Glass transition temperature (DSC measurement): 325 ° C
5% weight loss temperature (TGA measurement): 559 ° C
Tensile properties of thermosetting film (thickness 85 μm): elastic modulus 2.84 GPa, breaking strength 117 MPa, breaking elongation 11.8%

(Example 5)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and 1,4-dioxane (4 mL) were added, and bis (trimethylsilyl) acetamide (1.017 g, 5 mmol) was added thereto, followed by stirring at room temperature for 2 hours. To this solution, 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, and polymerization reaction was carried out in a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. An oligomer was produced. To this reaction solution, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and reacted at room temperature for 4 hours in a nitrogen stream to be terminally modified to obtain a uniform transparent solution of terminally modified amidic acid silyl ester oligomer. Got. A part of this solution was cast on a glass plate and dried under reduced pressure at 60 ° C. to obtain a powdered oligomer. The logarithmic viscosity was 0.16 dL / g (concentration 0.5 g / dL, measured in NMP at 30 ° C.). This terminal-modified amic acid silyl ester oligomer has the general formula (1), wherein R ₁ is a diphenyl ether group and a fluorenylidene diphenyl ether group (mixing ratio 50:50 mol%), R ₂ is a biphenyl group, and R ₃ is Represents a trimethylsilyl group, n = 4 on average.
IR (KBr, cm ⁻¹ ): 3344, 3060, 2956, 2215, 1656, 1603, 1541, 1498, 1408, 1220, 1169, 1046, 1014, 843
The remaining solution was cast on a glass plate, heated to 60 ° C., 150 ° C., 200 ° C., and 250 ° C. successively and dried under reduced pressure for 1 hour each to obtain a flaky terminal-modified imide oligomer.
IR (KBr, cm ⁻¹ ): 3053, 2212, 1776, 1719, 1614, 1499, 1371, 1236, 1168, 1111, 1081, 876, 826, 737
Elemental analysis: calculated value [calculated as C _218.5 H ₁₂₀ N ₁₀ O _27.5 ] carbon 78.92%, hydrogen 3.64%, nitrogen 4.21%; measured value carbon 78.71%, hydrogen 3.88%, nitrogen 4.38%
Average molecular weight (measured by standard polystyrene conversion using gel permeation chromatography): number average molecular weight 4000, polydispersity 1.5
This terminal-modified imide oligomer was heated at 370 ° C. for 1 hour with a hot press machine to obtain a film-like cured product.
IR (film, cm ⁻¹ ): 3058, 1776, 1718, 1615, 1499, 1371, 1236, 1168, 1081, 876, 827, 737
Glass transition temperature (DSC measurement): 327 ° C
5% weight loss temperature (TGA measurement): 560 ° C.
Tensile properties of thermosetting film (thickness 88 μm): elastic modulus 2.80 GPa, breaking strength 115 MPa, breaking elongation 11.1%

(Example 6)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and 2-methoxyethyl acetate (4 mL) were added, and bis (trimethylsilyl) acetamide (1.017 g, 5 mmol) was added thereto, followed by stirring at room temperature for 2 hours. To this solution, 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, and polymerization reaction was carried out in a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. An oligomer was produced. To this reaction solution, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and reacted at room temperature for 4 hours in a nitrogen stream to be terminally modified to obtain a uniform transparent solution of terminally modified amidic acid silyl ester oligomer. Got. A part of this solution was cast on a glass plate and dried under reduced pressure at 60 ° C. to obtain a powdered oligomer. The logarithmic viscosity was 0.16 dL / g (concentration 0.5 g / dL, measured in NMP at 30 ° C.). This terminal-modified amic acid silyl ester oligomer has the general formula (1), wherein R ₁ is a diphenyl ether group and a fluorenylidene diphenyl ether group (mixing ratio 50:50 mol%), R ₂ is a biphenyl group, and R ₃ is Represents a trimethylsilyl group, n = 4 on average.
IR (KBr, cm ⁻¹ ): 3344, 3060, 2956, 2215, 1656, 1603, 1541, 1498, 1408, 1220, 1169, 1046, 1014, 843
The remaining solution was cast on a glass plate, heated to 60 ° C., 150 ° C., 200 ° C., and 250 ° C. successively and dried under reduced pressure for 1 hour each to obtain a flaky terminal-modified imide oligomer.
IR (KBr, cm ⁻¹ ): 3053, 2212, 1776, 1719, 1614, 1499, 1371, 1236, 1168, 1111, 1081, 876, 826, 737
Elemental analysis: calculated value [calculated as C _218.5 H ₁₂₀ N ₁₀ O _27.5 ] carbon 78.92%, hydrogen 3.64%, nitrogen 4.21%; measured value carbon 78.62%, hydrogen 3.94%, nitrogen 4.50%
Average molecular weight (measured by standard polystyrene conversion using gel permeation chromatography): number average molecular weight 4000, polydispersity 1.5
This terminal-modified imide oligomer was heated at 370 ° C. for 1 hour with a hot press machine to obtain a film-like cured product.
IR (film, cm ⁻¹ ): 3058, 1776, 1718, 1615, 1499, 1371, 1236, 1168, 1081, 876, 827, 737
Glass transition temperature (DSC measurement): 326 ° C
5% weight loss temperature (TGA measurement): 560 ° C.
Tensile properties of thermosetting film (thickness 90 μm): elastic modulus 2.79 GPa, breaking strength 115 MPa, breaking elongation 10.9%

(Example 7)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube, 0.100 g (0.5 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (1.065 g, 2 mmol) and tetrahydrofuran (4 mL) were added, and bis (trimethylsilyl) acetamide (1.017 g, 5 mmol) was added thereto, followed by stirring at room temperature for 2 hours. To this solution, 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, and polymerization reaction was carried out in a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. An oligomer was produced. To this reaction solution, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and reacted at room temperature for 4 hours in a nitrogen stream to be terminally modified to obtain a uniform transparent solution of terminally modified amidic acid silyl ester oligomer. Got. A part of this solution was cast on a glass plate and dried under reduced pressure at 60 ° C. to obtain a powdered oligomer. The logarithmic viscosity was 0.19 dL / g (concentration 0.5 g / dL, measured in NMP at 30 ° C.). This terminal-modified amic acid silyl ester oligomer has the following general formula (1): R ₁ is a diphenyl ether group and a fluorenylidene diphenyl ether group (mixing ratio 20:80 mol%), R ₂ is a biphenyl group, R ₃ is Represents a trimethylsilyl group, n = 4 on average.
IR (KBr, cm ⁻¹ ): 3344, 3060, 2956, 2213, 1656, 1601, 1542, 1499, 1408, 1218, 1169, 1046, 1014, 843
The remaining solution was cast on a glass plate, heated to 60 ° C., 150 ° C., 200 ° C., and 250 ° C. successively and dried under reduced pressure for 1 hour each to obtain a flaky terminal-modified imide oligomer.
IR (KBr, cm ⁻¹ ): 3053, 2212, 1776, 1719, 1614, 1499, 1371, 1238, 1168, 1111, 1082, 876, 826, 737
Elemental analysis: calculated value [calculated as C ₂₅₆ H ₁₄₄ N ₁₀ O ₂₉ ] carbon 80.41%, hydrogen 3.80%, nitrogen 3.66%; measured value carbon 79.99%, hydrogen 3.89%, nitrogen 3.60%
Average molecular weight (measured by standard polystyrene conversion using gel permeation chromatography): number average molecular weight 4400, polydispersity 1.5
This terminal-modified imide oligomer was heated at 370 ° C. for 1 hour with a hot press machine to obtain a film-like cured product.
IR (film, cm ⁻¹ ): 3058, 1776, 1718, 1615, 1499, 1371, 1236, 1168, 1081, 876, 827, 737
Glass transition temperature (DSC measurement): 326 ° C
5% weight loss temperature (TGA measurement): 553 ° C
Tensile properties of thermosetting film (thickness 107 μm): elastic modulus 2.74 GPa, breaking strength 114 MPa, breaking elongation 11.1%

(Example 8)
In a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube, 1.332 g (2.5 mmol) of 9,9-bis [4- (4-aminophenoxy) phenyl] fluorene and tetrahydrofuran were added. 4 mL was added, 1.017 g (5 mmol) of bis (trimethylsilyl) acetamide was added thereto, and the mixture was stirred at room temperature for 2 hours. To this solution, 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, and polymerization reaction was carried out in a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. An oligomer was produced. To this reaction solution, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and reacted at room temperature for 4 hours in a nitrogen stream to be terminally modified to obtain a uniform transparent solution of terminally modified amidic acid silyl ester oligomer. Got. A part of this solution was cast on a glass plate and dried under reduced pressure at 60 ° C. to obtain a powdered oligomer. The logarithmic viscosity was 0.19 dL / g (concentration 0.5 g / dL, measured in NMP at 30 ° C.). The terminal-modified amic acid silyl ester oligomer is represented by the general formula (1), wherein R ₁ represents a fluorenylidene diphenyl ether group, R ₂ represents a biphenyl group, and R ₃ represents a trimethylsilyl group, and n = 4 on average. .
IR (KBr, cm ⁻¹ ): 3344, 3060, 2956, 2213, 1656, 1603, 1540, 1499, 1408, 1220, 1168, 1046, 1014, 843
The remaining solution was cast on a glass plate, heated to 60 ° C., 150 ° C., 200 ° C., and 250 ° C. successively and dried under reduced pressure for 1 hour each to obtain a flaky terminal-modified imide oligomer.
IR (KBr, cm ⁻¹ ): 3053, 2212, 1776, 1720, 1615, 1498, 1374, 1238, 1170, 1112, 1084, 876, 826, 738
Elemental analysis: calculated value [calculated as C ₂₈₁ H ₁₆₀ N ₁₀ O ₃₀ ] carbon 81.20%, hydrogen 3.88%, nitrogen 3.37%; measured value carbon 80.89%, hydrogen 3.98%, nitrogen 3.30%
Average molecular weight (measured by standard polystyrene conversion using gel permeation chromatography): number average molecular weight 4500, polydispersity 1.5
This terminal-modified imide oligomer was heated at 370 ° C. for 1 hour with a hot press machine to obtain a film-like cured product.
IR (film, cm ⁻¹ ): 3058, 1776, 1719, 1615, 1498, 1373, 1238, 1168, 1082, 876, 827, 737
Glass transition temperature (DSC measurement): 321 ° C
5% weight loss temperature (TGA measurement): 551 ° C
Tensile properties of thermosetting film (thickness: 119 μm): elastic modulus 2.78 GPa, breaking strength 110 MPa, breaking elongation 10.2%

Example 9
In a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube, 1.332 g (2.5 mmol) of 9,9-bis [4- (4-aminophenoxy) phenyl] fluorene and tetrahydrofuran were added. 4 mL was added, 1.017 g (5 mmol) of bis (trimethylsilyl) acetamide was added thereto, and the mixture was stirred at room temperature for 2 hours. To this solution, 0.441 g (1.5 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 0.155 g (0.5 mmol) of bis (3,4-carboxyphenyl) ether dianhydride And a polymerization reaction was carried out in a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours to produce a amide silyl ester oligomer. To this reaction solution, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and reacted at room temperature for 4 hours in a nitrogen stream to be terminally modified to obtain a uniform transparent solution of terminally modified amidic acid silyl ester oligomer. Got. A part of this solution was cast on a glass plate and dried under reduced pressure at 60 ° C. to obtain a powdered oligomer. The logarithmic viscosity was 0.19 dL / g (concentration 0.5 g / dL, measured in NMP at 30 ° C.). This terminal-modified amic acid silyl ester oligomer has the general formula (1) in which R ₁ is a fluorenylidene diphenyl ether group, R ₂ is a biphenyl group and a diphenyl ether group (mixing ratio 75:25 mol%), and R ₃ is Represents a trimethylsilyl group, n = 4 on average.
IR (KBr, cm ⁻¹ ): 3344, 3060, 2956, 2213, 1656, 1603, 1542, 1498, 1408, 1220, 1169, 1046, 1014, 843
The remaining solution was cast on a glass plate, heated to 60 ° C., 150 ° C., 200 ° C., and 250 ° C. successively and dried under reduced pressure for 1 hour each to obtain a flaky terminal-modified imide oligomer.
IR (KBr, cm ⁻¹ ): 3053, 2212, 1775, 1720, 1614, 1499, 1374, 1238, 1170, 1113, 1086, 876, 826, 740
Elemental analysis: calculated value [calculated as C ₂₈₁ H ₁₆₀ N ₁₀ O ₃₁ ] carbon 80.89%, hydrogen 3.86%, nitrogen 3.36%; measured value carbon 80.51%, hydrogen 3.95%, nitrogen 3.31%
Average molecular weight (measured by standard polystyrene conversion using gel permeation chromatography): number average molecular weight 4500, polydispersity 1.5
This terminal-modified imide oligomer was heated at 370 ° C. for 1 hour with a hot press machine to obtain a film-like cured product.
IR (film, cm ⁻¹ ): 3058, 1776, 1719, 1615, 1499, 1371, 1236, 1168, 1081, 876, 827, 737
Glass transition temperature (DSC measurement): 319 ° C
5% weight loss temperature (TGA measurement): 552 ° C
Tensile properties of thermosetting film (thickness 104 μm): elastic modulus 2.78 GPa, breaking strength 112 MPa, breaking elongation 10.4%

(Example 10)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube, 0.73 g (2.5 mmol) of 1,3-bis (4-aminophenoxy) benzene and 4 mL of tetrahydrofuran were added. To the solution, 1.017 g (5 mmol) of bis (trimethylsilyl) acetamide was added and stirred at room temperature for 2 hours. To this solution, 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, and polymerization reaction was carried out in a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. An oligomer was produced. To this reaction solution, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and reacted at room temperature for 4 hours in a nitrogen stream to be terminally modified to obtain a uniform transparent solution of terminally modified amidic acid silyl ester oligomer. Got. A part of this solution was cast on a glass plate and dried under reduced pressure at 60 ° C. to obtain a powdered oligomer. The logarithmic viscosity was 0.16 dL / g (concentration 0.5 g / dL, measured in NMP at 30 ° C.). The terminal-modified amidic acid silyl ester oligomer in the general formula (1), R ₁ represents a phenylene phenyl ether group, R ₂ represents a biphenyl group, R ₃ represents a trimethylsilyl group, and n = 4 on average.
IR (KBr, cm ⁻¹ ): 3344, 3060, 2956, 2213, 1657, 1603, 1541, 1498, 1408, 1220, 1169, 1046, 1014, 843
The remaining solution was cast on a glass plate, heated to 60 ° C., 150 ° C., 200 ° C., and 250 ° C. successively and dried under reduced pressure for 1 hour each to obtain a flaky terminal-modified imide oligomer.
IR (KBr, cm ⁻¹ ): 3053, 2212, 1775, 1720, 1614, 1498, 1374, 1238, 1171, 1113, 1086, 876, 826, 740
Elemental analysis: calculated value [calculated as C ₁₈₆ H ₁₀₀ N ₁₀ O ₃₀ ] carbon 75.61%, hydrogen 3.41%, nitrogen 4.74%; measured value carbon 75.22%, hydrogen 3.53%, nitrogen 4.68%
Average molecular weight (measured by standard polystyrene conversion using gel permeation chromatography): number average molecular weight 3500, polydispersity 1.5
This terminal-modified imide oligomer was heated at 370 ° C. for 1 hour with a hot press machine to obtain a film-like cured product.
IR (film, cm ⁻¹ ): 3058, 1776, 1718, 1615, 1499, 1371, 1236, 1168, 1081, 876, 827, 737
Glass transition temperature (DSC measurement): 252 ° C
5% weight loss temperature (TGA measurement): 548 ° C
Tensile properties of thermosetting film (thickness 104 μm): elastic modulus 2.54 GPa, breaking strength 108 MPa, breaking elongation 15.4%

(Comparative Example 1)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and 2-butanone (4 mL) were added, and 0.53 g (3 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added to the suspension. And stirred at 60 ° C. for 2 hours and at room temperature for 2 hours. Next, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and stirred for 4 hours at room temperature under a nitrogen stream. However, the solution remained a cloudy heterogeneous solution with no dissolution.

(Comparative Example 2)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and tetrahydrofuran (4 mL) were added. To this suspension was added 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (0.588 g, 2 mmol). The mixture was stirred at 60 ° C. for 2 hours and at room temperature for 2 hours under a nitrogen stream. Next, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and stirred for 4 hours at room temperature under a nitrogen stream. However, the solution remained a cloudy heterogeneous solution with no dissolution.

(Comparative Example 3)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and cyclohexanone (4 mL) were added, and after dissolution, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (0.588 g, 2 mmol) was added to the solution. The mixture was stirred under a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. Next, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and stirred for 4 hours at room temperature under a nitrogen stream. However, the solution remained a cloudy heterogeneous solution with no dissolution.

(Comparative Example 4)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and 1,4-dioxane (4 mL) were added, and 0.53 g (3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride) was added to the suspension. 2 mmol), and stirred under a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. Next, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and stirred for 4 hours at room temperature under a nitrogen stream. However, the solution remained a cloudy heterogeneous solution with no dissolution.

(Comparative Example 5)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube was added 0.250 g (1.25 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (0.666 g, 1.25 mmol) and 2-methoxyethyl acetate (4 mL) were added, and 0.53 g (3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride) was added to the suspension. 2 mmol), and stirred under a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. Next, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and stirred for 4 hours at room temperature under a nitrogen stream. However, the solution remained a cloudy heterogeneous solution with no dissolution.

(Comparative Example 6)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube, 0.100 g (0.5 mmol) of 4,4′-diaminodiphenyl ether, 9,9-bis [4- (4- Aminophenoxy) phenyl] fluorene (1.065 g, 2 mmol) and tetrahydrofuran (4 mL) were added, and 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (0.588 g, 2 mmol) was added to the suspension. The mixture was stirred at 60 ° C. for 2 hours and at room temperature for 2 hours under an air stream. Next, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and stirred for 4 hours at room temperature under a nitrogen stream. However, the solution remained a cloudy heterogeneous solution with no dissolution.

(Comparative Example 7)
In a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube, 1.332 g (2.5 mmol) of 9,9-bis [4- (4-aminophenoxy) phenyl] fluorene and tetrahydrofuran were added. 4 mL was added, 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added to this solution, and the mixture was stirred at 60 ° C. for 2 hours and at room temperature for 2 hours under a nitrogen stream. Next, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and stirred for 4 hours at room temperature under a nitrogen stream. However, the solution remained a cloudy heterogeneous solution with no dissolution.

(Comparative Example 8)
In a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube, 1.332 g (2.5 mmol) of 9,9-bis [4- (4-aminophenoxy) phenyl] fluorene and tetrahydrofuran were added. 4 mL was added to this solution and 0.441 g (1.5 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 0.155 g of bis (3,4-carboxyphenyl) ether dianhydride ( 0.5 mmol), and stirred under a nitrogen stream at 60 ° C. for 2 hours and at room temperature for 2 hours. Next, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and stirred for 4 hours at room temperature under a nitrogen stream. However, the solution remained a cloudy heterogeneous solution with no dissolution.

(Comparative Example 9)
To a three-necked 100 mL flask equipped with a thermometer, a stirrer, a condenser tube, and a nitrogen inlet tube, 0.73 g (2.5 mmol) of 1,3-bis (4-aminophenoxy) benzene and 4 mL of tetrahydrofuran were added. 0.588 g (2 mmol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added to the suspension, and the mixture was stirred at 60 ° C. for 2 hours and at room temperature for 2 hours under a nitrogen stream. Next, 0.248 g (1 mmol) of 4- (2-phenylethynyl) phthalic anhydride was added and stirred for 4 hours at room temperature under a nitrogen stream. However, the solution remained a cloudy heterogeneous solution with no dissolution.

  The present invention is excellent in solubility in low-boiling organic solvents other than amide solvents and moldability such as low melt viscosity, can be easily formed into a film, and has a machine such as heat resistance and elastic modulus, tensile strength and elongation of a cured product. Terminal-modified amic acid silyl ester oligomers and varnishes with high mechanical properties, terminal-modified imide oligomers and cured products thereof, and a wide range that requires easy moldability and high heat resistance including aircraft and space industry equipment Provide materials available in the field.

Claims (6)

A terminal-modified amic acid silyl ester oligomer represented by the general formula (1).

(Wherein R ₁ represents a divalent aromatic diamine residue, R ₂ represents a tetravalent aromatic tetracarboxylic acid residue, R ₃ represents a monovalent organosilicon group represented by Formula 2, n satisfies the relationship 1 ≦ n ≦ 20.)

(Wherein _represents R _4, R 5, _{R 6} each independently represents an alkyl group or a monovalent aromatic group having 1 to 4 carbon atoms.)   A varnish obtained by dissolving the terminal-modified amic acid silyl ester oligomer according to claim 1 in an organic solvent in an amount of 20 to 50% by mass. A terminally modified amidic acid silyl ester oligomer represented by the general formula (1) or a varnish thereof reacted in one pot from an aromatic diamine, a silylating agent, an aromatic tetracarboxylic acid, a phenylethynyl phthalic anhydride terminal agent in an organic solvent Manufacturing method.

(Wherein R ₁ represents a divalent aromatic diamine residue, R ₂ represents a tetravalent aromatic tetracarboxylic acid residue, R ₃ represents a monovalent organosilicon group represented by Formula 2, n satisfies the relationship 1 ≦ n ≦ 20.)

(Wherein _represents R _4, R 5, _{R 6} each independently represents an alkyl group or a monovalent aromatic group having 1 to 4 carbon atoms.)   A terminal-modified imide oligomer obtained by heating the terminal-modified amic acid silyl ester oligomer according to claim 1 or the varnish according to claim 2.   A cured product obtained by heating the terminal-modified amic acid silyl ester oligomer according to claim 1 or the varnish according to claim 2.   The hardened | cured material of Claim 5 whose glass transition temperature (Tg) is 250 degreeC or more.