TW202348597A - Novel diamine, method for producing the same, and polyamic acid and polyimide produced from the diamine - Google Patents

Abstract

Provided are a diamine represented by formula (1), a method for producing the same, and a polyamic acid and polyimide produced from the diamine.

Description

Novel diamine and its production method, as well as polyamic acid and polyimide produced from the diamine

The present invention relates to a novel ester group-containing diamine that can be used as a raw material for polyimide resin and the like, a method for producing the same, and polyamic acid and polyimide produced from the diamine.

Polyimide combines the highest levels of heat resistance, chemical resistance, electrical insulation, radiation resistance, etc. among existing resins. It can be easily combined with the characteristics of various uses through the combination of raw materials, so it can Used in a wide range of fields.

Among them, as for the use of polyimide, with the popularity of fifth-generation communication systems in recent years, it has focused on flexible printed wiring boards (FPC). Polyimide, which is a substrate material for FPC, undergoes dimensional changes due to exposure to various thermal cycles during the packaging step. Therefore, in order to suppress this, it is desirable to make polyimide with high heat resistance (for example, glass The transfer temperature (Tg) is higher than the step temperature), and the linear thermal expansion coefficient (CTE) is as low as possible (for example, the same as or lower than the CTE of copper foil (about 20 ppm/K)).

A diamine represented by the following formula (8) is known as a polyimide diamine that provides such high heat resistance and has low CTE (Patent Document 1).

[Prior technical literature]

[Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 08-048773

However, the diamine represented by the above formula (8) has extremely poor solvent solubility. Therefore, in order to polymerize in a homogeneous system, the diamine must be completely dissolved under heating and mixed with the acid dianhydride. Therefore, there are problems. This may cause problems such as manufacturing steps becoming complicated or production efficiency being reduced.

An object of the present invention is to provide a novel diamine having a structure similar to the diamine represented by the above formula (8) and having excellent solvent solubility.

As a result of intensive research, the present inventors found that the diamine represented by the following formula (1) exhibits excellent solvent solubility and can solve the aforementioned problems. Specifically, the present invention includes the following inventions.

[1] A diamine represented by the following formula (1),

[2] A method for producing the diamine described in [1], which is to reduce the dinitro compound represented by the following formula (2):

[3] A dinitro compound represented by the following formula (2),

[4] A polyamide having a repeating unit represented by the following general formula (3),

(式中，A表示4價之芳香族基或4價之脂肪族基。)。

(In the formula, A represents a tetravalent aromatic group or a tetravalent aliphatic group.).

[5] A polyimide having a repeating unit represented by the following general formula (4),

(式中，A表示4價之芳香族基或4價之脂肪族基。)。

(In the formula, A represents a tetravalent aromatic group or a tetravalent aliphatic group.).

[6] A polyamic acid solution containing the polyamic acid described in [4] and a solvent.

[7] A film containing the polyamide according to [4].

[8] A film containing the polyimide according to [5].

[9] A laminated body having a layer containing the polyimide according to [5].

The diamine of the present invention (diamine represented by the above formula (1)) has excellent solvent solubility although it has a similar structure to the diamine represented by the above formula (8). Therefore, the reaction can proceed uniformly around room temperature (25°C) without special heating. Therefore, the polymerization reaction can sufficiently proceed around room temperature (25°C), and oligomerization or coagulation can be suppressed. After gelation, a homogeneous solution of the polyamic acid of the present invention (polyamic acid having a repeating unit represented by the above general formula (3)) is obtained.

Furthermore, the polyimide of the present invention (polyimide having a repeating unit represented by the general formula (4)) produced from the diamine of the present invention not only has high Tg and low CTE, but also has low dielectric properties. (Low dielectric constant, low dielectric loss tangent) is also excellent. In recent years, FPC substrate materials for 5G applications are required to have low dielectric properties (low dielectric constant, low dielectric loss tangent) from the perspective of reducing transmission loss (Transmission Loss). Therefore, the polyethylene of the present invention An amine can be suitably used as an FPC substrate material, especially a high-frequency FPC substrate material (for example, a resin substrate in a laminated body such as a flexible copper foil laminated board or a cover layer film).

Figure 1 is a ¹ H-NMR chart of the dinitro compound represented by the above formula (2) obtained in Example 1.

Figure 2 is a ¹ H-NMR chart of the diamine represented by the above formula (1) obtained in Example 2.

Figure 3 is an LC-MS chart of the diamine represented by the above formula (1) obtained in Example 2.

In this specification, when a numerical range is expressed as "A to B", it means above A and below B.

<Diamine of the present invention>

The diamine system of the present invention has a structure represented by the above formula (1).

The diamine system of the present invention can be obtained by, for example, reacting tert-butylhydroquinone or its derivatives with 4-nitrobenzoic acid or its derivatives to obtain the dinitro compound represented by the above formula (2) ( It is produced by reducing the nitro group of the dinitro compound (amination reaction).

Examples of the method for the above-mentioned esterification reaction include: direct dehydration reaction between tert-butylhydroquinone and 4-nitrobenzoic acids at high temperature; use of N,N'-dicyclohexylcarbodiimide, etc. Dehydration reagent is a method of dehydrating and condensing tert-butylhydroquinone and 4-nitrobenzoic acids; reacting the diacetate ester of tert-butylhydroquinone with 4-nitrobenzoic acids at high temperature. A method of removing acetic acid and performing esterification (ester exchange method); a method of reacting tert-butylhydroquinone and 4-nitrobenzoyl chloride in the presence of an oxygen scavenger (halide method); using toluene sulfonate A method for activating the carboxyl group of 4-nitrobenzoic acids and reacting it with tert-butylhydroquinone using a chloride/N,N-dimethylformamide/pyridine mixture wait. Among these methods, the chlorination method is preferred from the viewpoint of economy and reactivity. Hereinafter, the chlorination method will be described in detail.

Examples of the 4-nitrobenzyl halides in the above-mentioned chloride method include 4-nitrobenzyl chloride, 4-nitrobenzyl bromide, 4-nitrobenzyl iodide, and the like. Among these 4-nitrobenzoyl halides, 4-nitrobenzoyl chloride is preferred. For example, the usage amount of 4-nitrobenzoyl halide is 2 to 4 moles, preferably 2 to 3 moles, based on 1 mole of tert-butylhydroquinone. If the usage amount is 2 moles or more, a sufficient reaction rate can be obtained, and if it is 4 moles or less, the amount of unreacted 4-nitrobenzoyl halide can be reduced, and the properties of the obtained diamine of the present invention can be further improved. Purity.

Examples of the oxygen scavenger in the above-mentioned halogen method include organic tertiary amines such as pyridine, triethylamine, N,N-dimethylaniline, propylene oxide, allylglycidyl ether, etc. Epoxy; potassium carbonate, sodium hydroxide and other inorganic bases, etc. These oxygen scavengers may be used alone, or two or more types may be used in combination. Among these oxygen scavengers, pyridine is preferred because it is cheap and easy to separate and remove after the reaction. For example, the amount of the oxygen scavenger used is 2 moles to 4 moles, preferably 2 moles to 3 moles, based on 1 mole of tert-butylhydroquinone. If the usage amount is 2 moles or more, sufficient reaction speed can be obtained, and if it is 4 moles or less, the generation of impurities can be suppressed.

烷、環戊基甲基醚、二甘醇二甲醚、三甘醇二甲醚等醚系溶劑；甲苯、二甲苯等芳香族烴系溶劑；氯苯、二氯苯等鹵化芳香族烴系溶劑；乙腈、丙腈、丁腈、異丁腈、戊腈、異戊腈、苯甲腈等腈系溶劑；N-甲基-2-吡咯啶酮、N,N-二甲基乙醯胺、N,N-二乙基乙醯 胺、N,N-二甲基甲醯胺、1,3-二甲基-2-咪唑啶酮等醯胺系溶劑等。此等溶劑之中，從取得性及操作性之點而言，以醚系溶劑、芳香族烴系溶劑、腈系溶劑為佳。此等溶劑可單獨使用，亦可併用2種以上。又，相對於第三丁基氫醌1重量倍，使用溶劑時之使用量，例如為1重量倍至30重量倍，較佳係1重量倍至5重量倍。 The halogenation method is usually carried out in the presence of a solvent. Examples of solvents that can be used in the halogenation method include ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclohexanone, and acetophenone; 1,2 -Dimethoxyethane, 1,2-diethoxyethane, tetrahydrofuran, dibutyl ether, diethyl ether, 1,4-di

Ether solvents such as alkane, cyclopentyl methyl ether, diglyme, triglyme and other ether solvents; aromatic hydrocarbon solvents such as toluene and xylene; halogenated aromatic hydrocarbon solvents such as chlorobenzene and dichlorobenzene. Solvents; nitrile solvents such as acetonitrile, propionitrile, butyronitrile, isobutyronitrile, valeronitrile, isovaleronitrile, and benzonitrile; N-methyl-2-pyrrolidone, N,N-dimethylacetamide , N,N-diethyl acetamide, N,N-dimethylformamide, 1,3-dimethyl-2-imidazolidinone and other amide solvents. Among these solvents, ether solvents, aromatic hydrocarbon solvents, and nitrile solvents are preferred from the viewpoint of availability and workability. These solvents can be used alone, or two or more types can be used in combination. Moreover, the usage amount when using a solvent is, for example, 1 to 30 weight times, preferably 1 to 5 weight times, relative to 1 weight of tert-butylhydroquinone.

The halogenation method is implemented, for example, at -10°C to 120°C, preferably at -5°C to 100°C, and more preferably at 20°C to 90°C. If the reaction temperature is 120°C or lower, by-products can be further reduced, and if the reaction temperature is -10°C or higher, a sufficient reaction rate can be obtained.

Examples of the halogen method include: adding a separately prepared tert-butyl group to a solution containing 4-nitrobenzoyl halide and the above-mentioned solvent intermittently or continuously under stirring so that the temperature range becomes the above-mentioned range. After the solution of hydroquinone, oxygen scavenger and the above solvent, the reaction is further continued in the above temperature range, or in a solution containing 4-nitrobenzoyl halide, tert-butylhydroquinone and the above solvent, to A method in which an oxygen scavenger or a solution containing an oxygen scavenger and the above solvent is added intermittently or continuously to achieve the above temperature range, and then the reaction is further continued in the above temperature range, etc.

After the halogenation method is carried out, the reaction mixture obtained can be used directly in the amination reaction described below, or can be carried out by commonly used purification methods (extraction, washing, adsorption, steam distillation, crystallization, column purification, etc.) Purification. In addition, the purification system may be performed only once or a plurality of times.

Examples of the amination reaction method include: dissolving the dinitro compound represented by the above formula (2) in an inert solvent, and supporting transition metal atoms such as palladium or platinum on activated carbon in a hydrogen atmosphere. Catalyst and reduction method (contact reduction method), etc.

Examples of the catalyst system in the contact reduction method include a catalyst in which transition metal atoms such as palladium or platinum are supported on activated carbon. Among them, from the viewpoint of reaction speed, it is preferable to support palladium on activated carbon. Catalyst (palladium/carbon) or catalyst (platinum/carbon) formed by loading platinum on activated carbon. These catalysts can be used alone, or two or more types can be used in combination. Regarding the weight of transition metal atoms in the catalyst, relative to 1 weight times of the dinitro compound represented by the above formula (2), the usage amount of these catalysts is, for example, 0.0001 to 0.01 weight times.

烷、環戊基甲基醚、二甘醇二甲醚、三甘醇二甲醚等醚系溶劑；乙酸乙酯、乙酸丁酯、乙酸異丁酯、γ-丁內酯、γ-戊內酯、δ-戊內酯、γ-己內酯、ε-己內酯、α-甲基-γ-丁內酯等酯系溶劑；丙酮、甲基乙基酮、甲基異丁基酮、二異丁基酮、環己酮、苯乙酮等酮系溶劑；氯仿、二氯甲烷、三氯甲烷、1,2-二氯乙烷等鹵烷系溶劑；甲苯、二甲苯等芳香族烴系溶劑；N-甲基-2-吡咯啶酮、N,N-二甲基乙醯胺、N,N-二乙基乙醯胺、N,N-二甲基甲醯胺、1,3-二甲基-2-咪唑啶酮等醯胺系溶劑；二甲基亞碸、環丁碸等碸系溶劑；甲基吡啶；吡啶等。此等溶劑之中，以醯胺系溶劑為較佳。此等溶劑係可單獨使用，亦可併用2種以上。相對於上述式(2)所示的二硝基化合物1重量倍，作為此等溶劑之使用量例如為2至10重量倍。 As a solvent in the contact reduction method, for example, as long as it does not react with the dinitro compound represented by the above formula (2) or the diamine represented by the above formula (1) that is a product, and during the contact reduction method Those that do not react need only be used, and examples include: 1,2-dimethoxyethane, 1,2-diethoxyethane, tetrahydrofuran, dibutyl ether, diethyl ether, 1,4-dimethoxyethane,

Alkane, cyclopentyl methyl ether, diglyme, triglyme and other ether solvents; ethyl acetate, butyl acetate, isobutyl acetate, γ-butyrolactone, γ-valerolactone ester, δ-valerolactone, γ-caprolactone, ε-caprolactone, α-methyl-γ-butyrolactone and other ester solvents; acetone, methyl ethyl ketone, methyl isobutyl ketone, Ketone solvents such as diisobutyl ketone, cyclohexanone, and acetophenone; haloalkane solvents such as chloroform, dichloromethane, chloroform, and 1,2-dichloroethane; aromatic hydrocarbons such as toluene and xylene Solvents; N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylformamide, 1,3 - Amide solvents such as dimethyl-2-imidazolidinone; styrene solvents such as dimethyl tyrosine and cyclotenine; methylpyridine; pyridine, etc. Among these solvents, amide solvents are preferred. These solvents can be used alone, or two or more types can be used in combination. The usage amount of these solvents is, for example, 2 to 10 times by weight relative to 1 time by weight of the dinitro compound represented by the above formula (2).

From the viewpoint of increasing the reaction speed and suppressing the generation of impurities, the contact reduction method is implemented at, for example, 20°C to 160°C, preferably 20°C to 100°C.

After performing the contact reduction method, for example, removing the catalyst by filtration, the reaction mixture obtained is dropped into a solvent in which the diamine is hardly soluble (hereinafter, a solvent in which the target substance is hardly soluble) represented by the above formula (1) is sometimes referred to as The diamine represented by the above formula (1) can be separated by a method such as "weak solvent"). The diamine represented by the above formula (1) obtained in this way can be used directly in subsequent steps, but it can also be purified by commonly used purification methods (extraction, washing, adsorption, steam distillation, crystallization, column purification etc.) for purification. In addition, the purification system may be performed only once, or may be performed a plurality of times.

<Polyamide of the present invention and its production method>

The polyamide of the present invention has a repeating unit represented by the above general formula (3). In addition, in the above general formula (3), the two carboxyl groups bonded to the structural unit A are described as cis positions for convenience, but in reality, cis positions and trans positions are mixed.

The structural unit A of the general formula (3) represents a tetravalent aromatic group or a tetravalent aliphatic group. Furthermore, the tetravalent aromatic group is derived from aromatic tetracarboxylic dianhydride, and the tetravalent aliphatic group is derived from aliphatic tetracarboxylic acid.

The structural unit A in the general formula (3) preferably includes at least one of the structures represented by the following formulas (5) to (7). In addition, * represents a bonding point.

The molecular weight of the polyamide of the present invention is, for example, 10,000 to 500,000 in terms of weight average molecular weight, preferably 10,000 to 300,000, more preferably 20,000 to 200,000. If the molecular weight of polyamide is more than 10,000, it can easily maintain good mechanical properties. In addition, if the molecular weight of the polyamide acid is 500,000 or less, the molecular weight can be easily controlled during synthesis, and a solution of appropriate viscosity can be easily obtained, and the operation is often easy. In addition, the molecular weight of polyamide can be measured by a common method such as GPC (gel permeation chromatography) method.

The polyamide of the present invention is, for example, a diamine represented by the above formula (1) (hereinafter, sometimes referred to as "the diamine of the present invention") and, if necessary, other diamines other than the diamine of the present invention. A solution (hereinafter, a polymerization solvent) can be obtained by a method such as a method in which an amine (hereinafter, sometimes referred to as "other diamine") is dissolved in a solvent (polymerization solvent), and then acid dianhydride powder is added and polymerized. Sometimes called "polyamide solution"). Since the diamine solvent of the present invention has excellent solubility, the reaction can proceed uniformly at room temperature (25°C) without heating, and polymerization can be fully carried out at room temperature (25°C). The reaction also inhibits oligomerization or gelation, thereby obtaining a homogeneous solution of the polyamide of the present invention. Therefore, the temperature during polymerization is preferably 10°C to 30°C.

唑、9,9-雙[4-(4-胺基苯氧基)苯基]茀、2,2’-雙(3-磺丙氧基)-4,4’-二胺基聯苯、4,4’-雙(4-胺基苯氧基)聯苯-3,3’-二磺酸等。此等其他二胺係可使用1種或併用2種以上。併用其他二胺時，全部二胺中之其他二胺之使用量例如為90重量%以下，較佳係70重量%以下。 Examples of other diamines include aromatic diamines, aliphatic diamines, alicyclic diamines, and the like. More specifically, examples include: 1,4-diaminobenzene, 1,3-diaminobenzene, 2,4-diaminotoluene, 4,4-diaminodiphenylmethane, 4, 4'-Diaminodiphenyl ether, 3,4'-Diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-diamine Methyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,7-diamino-dimethylbiphenyl Benzothiophene-5,5-dioxide, 4,4-diaminobenzophenone, 3,3'-diaminobenzophenone, 4,4'-bis(4-aminophenyl) ) thioether, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminobenzoaniline, 1,3-bis(4-aminophenoxy)propane, 1,4- Bis(4-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)pentane, 1,3-bis(4-aminophenoxy)-2,2-bis Methylpropane, 1,2-bis[2-(4-aminophenoxy)ethoxy]ethane, 9,9-bis(4-aminophenyl)fluoride, 1-(4-amino Phenyl)-2,3-dihydro-1,3,3-trimethyl-1H-indene-5-amine, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis (4-Aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'- Bis(3-aminophenoxy)biphenyl, 2,2-bis(4-aminophenoxyphenyl)propane, bis[4-(4-aminophenoxy)phenyl]terine, bis [4-(3-Aminophenoxy)phenyl]trines, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 3,3'-dicarboxy-4 ,4'-Diaminodiphenylmethane, 4,6-dihydroxy-1,3-phenylenediamine, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 2,2- Bis(3-amino-4-hydroxyphenyl)-hexafluoropropane, 3,3',4,4'-tetraaminobiphenyl, 1,6-diaminohexane, 1,3-bis( 3-Aminopropyl)-1,1,3,3-tetramethyldisiloxane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, 4 ,4'-methylenebis(4-cyclohexylamine), 1,4-diaminocyclohexane, bicyclo[2.2.1]heptanebis(methylamine), tricyclo[3.3.1.13.7 ] Decane-1,3-diamine, 4-aminobenzoic acid-4-aminophenyl ester, 2-(4-aminophenyl)-5-aminobenzo

Azole, 9,9-bis[4-(4-aminophenoxy)phenyl]fluorine, 2,2'-bis(3-sulfopropoxy)-4,4'-diaminobiphenyl, 4,4'-bis(4-aminophenoxy)biphenyl-3,3'-disulfonic acid, etc. These other diamines can be used alone or in combination of two or more types. When other diamines are used together, the usage amount of other diamines in all diamines is, for example, 90% by weight or less, preferably 70% by weight or less.

Examples of acid dianhydrides include: pyromelite acid anhydride, oxyphthalic acid dianhydride, biphenyl-3,4,3',4'-tetracarboxylic dianhydride, benzophenone-3,4, 3',4'-tetracarboxylic dianhydride, diphenylsine- 3,4,3',4'-tetracarboxylic dianhydride, 4,4'-(2,2-hexafluoroisopropylidene) diphthalic acid dianhydride, m-terphenyl-3,4, 3',4'-tetracarboxylic dianhydride, p-terphenyl-3,4,3',4'-tetracarboxylic dianhydride, cyclobutane-1,2,3,4-tetracarboxylic acid dianhydride, 1-carboxymethyl-2,3,5-cyclopentanetricarboxylic acid-2,6:3,5-dicanhydride, cyclohexane-1,2,4,5-tetracarboxylic dianhydride , Butane-1,2,3,4-tetracarboxylic dianhydride, 4-phenylethynyl phthalic anhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, bis(1,3-di Side oxygen group-1,3-dihydroisobenzofuran-5-carboxylic acid) 1,4-phenylene ester, etc. Among these acid dianhydrides, preferred ones corresponding to the structural unit A in the above general formula (3) are pyromelite acid anhydride and biphenyl-3,4,3',4'-tetrakis. Carboxylic dianhydride, bis(1,3-dihydroisobenzofuran-5-carboxylic acid) 1,4-phenylene ester. These acid dianhydrides may be used alone, or two or more types may be used in combination. For example, when the diamine of the present invention and other diamines are used together, the usage amount of the acid dianhydride is 0.9 mole to 1.1 mole relative to 1 mole of all diamines including other diamines, thereby further improving polymerization. From a temperature perspective, the preferred range is 0.95 mol to 1.05 mol.

烷、環戊基甲基醚、二甘醇二甲醚、三甘醇二甲醚等醚系溶劑；丙酮、甲基乙基酮、甲基異丁基酮、二異丁基酮、環己酮、苯乙酮等酮系溶劑；甲苯、二甲苯等芳香族烴系溶劑；氯苯、二氯 苯等鹵化芳香族烴系溶劑；二甲基亞碸、環丁碸等碸系溶劑等。此等聚合溶劑之中，以N,N-二甲基甲醯胺、N,N-二甲基乙醯胺、N-甲基-吡咯啶酮等醯胺系溶劑為佳。此等聚合溶劑係可單獨使用，亦可併用2種以上。 Examples of the polymerization solvent include N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-diethylacetamide, and N,N-dimethylformamide. Amine, 1,3-dimethyl-2-imidazolidinone and other amide solvents; ethyl acetate, butyl acetate, isobutyl acetate, γ-butyrolactone, γ-valerolactone, δ-valerolactone Ester solvents such as ester, γ-caprolactone, ε-caprolactone, α-methyl-γ-butyrolactone; carbonate solvents such as ethyl carbonate and propyl carbonate; triethylene glycol, ethylene glycol, etc. Baserosu, butylcellosu, propylene glycol methyl ether acetate, 2-methylcellosu acetate, ethylcellosu acetate, butylcellosu acetate, diethyl Diol-based solvents such as diol; phenol-based solvents such as phenol, o-cresol, m-cresol, p-cresol, 3-chlorophenol, 4-chlorophenol; 1,2-dimethoxyethane, 1,2-diethoxyethane, tetrahydrofuran, dibutyl ether, diethyl ether, 1,4-di

Alkanes, cyclopentyl methyl ether, diglyme, triglyme and other ether solvents; acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclohexane Ketone-based solvents such as ketone and acetophenone; aromatic hydrocarbon-based solvents such as toluene and xylene; halogenated aromatic hydrocarbon-based solvents such as chlorobenzene and dichlorobenzene; dimethyl sulfoxide, cyclobutane and other styrene-based solvents, etc. Among these polymerization solvents, amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-pyrrolidone are preferred. These polymerization solvents may be used alone, or two or more types may be used in combination.

The amount used as the polymerization solvent is such that the total concentration of the monomer components (diamine + acid dianhydride) in the reaction system is usually 5 to 40% by weight, preferably 10 to 30% by weight. . By performing polymerization in a monomer concentration range of 5% to 40% by weight, a polyamide solution with a high degree of polymerization can be obtained uniformly. In addition, if the polymerization is performed at a concentration lower than the above-mentioned monomer concentration range, the degree of polymerization of the polyamide acid is not high enough, and the final polyimide film will be brittle. If the polymerization is performed at a concentration higher than the above-mentioned monomer concentration range, When polymerizing at a certain concentration, the monomer may not be fully dissolved or the reaction solution may become uneven and gel. The polyamide solution represented by the general formula (3) obtained by the above method is usually used directly in the polyamide imidization step performed by the method described below.

<Polyimide of the present invention and its manufacturing method>

The polyimide system of the present invention has repeating units represented by the above general formula (4). In addition, the structural unit A in the above-mentioned general formula (4) is the same as the structural unit A in the above-mentioned general formula (3), and the preferred aspects thereof are also the same.

The polyimide of the present invention can be produced by subjecting the polyamide of the present invention obtained by the above method to a dehydration ring-closure reaction (imidization reaction). Examples of methods for the imidization reaction include thermal imidization and chemical imidization. First, the thermal imidization method will be described in detail.

Examples of the thermal imidization method include a method in which the polyamide solution of the present invention obtained by the above method is poured onto a glass plate and heated in a vacuum, in an inert gas such as nitrogen, or in air. More specifically, for example, the polyamide solution of the present invention is poured into Inject it on the glass plate, heat it in an oven at 50°C to 190°C, preferably 100°C to 180°C, and dry it to form a polyamide film (thin film). Furthermore, heat it at 200°C to 400°C. Heating at ℃, preferably at 230℃ to 350℃, to carry out the imidization reaction, a polyimide film (film) can be obtained. In addition, the imidization reaction is preferably carried out in vacuum or in an inert gas.

Next, the chemical imidization method will be described in detail. Examples of the chemical imidization method include a method in which the polyamic acid of the present invention obtained by the above method is subjected to a dehydration ring-closure reaction in a solution in the presence of an anhydride of an organic acid and a base. More specifically, for example, a solvent is added to the polyamic acid solution as necessary to adjust the viscosity of the solution to an appropriate solution that is easy to stir, and a dehydration ring-closing agent composed of an anhydride of an organic acid and a base is added thereto while stirring. Chemical imidization agent), stir at 0°C to 100°C, preferably at 10°C to 50°C for 1 hour to 72 hours, to carry out the imidization reaction to obtain polyimide. Examples of solvents that can be used include those that are the same as the polymerization solvent for polyamide acid, and preferred embodiments are also the same. Examples of organic acid anhydrides that can be used include acetic anhydride, propionic anhydride, and the like. Among them, acetic anhydride is preferred in terms of ease of handling or separation. Examples of the base include tertiary amines such as pyridine, triethylamine, and quinoline. Among them, pyridine is preferred in terms of ease of handling and separation. Relative to the theoretical dehydration amount of polyamide 1 mole, the usage amount of organic acid anhydride is usually 1 mole to 10 mole, preferably 2 mole to 5 mole. In addition, the usage amount of the base is usually 0.1 mole to 2 mole, preferably 0.2 mole to 1 mole, based on 1 mole of the anhydride of the organic acid.

Since the reaction mixture obtained by the above chemical imidization method contains unreacted alkali, anhydride of organic acid, by-products, etc. (hereinafter, these are sometimes collectively referred to as impurities), these can be removed and Polyimide for isolation/purification. Known methods can be used as the purification method. For example, the following method can be applied: adding the reaction mixture obtained after the imidization reaction while stirring Methods such as precipitating polyimide in a large amount of weak solvent, recovering polyimide powder, repeatedly washing to remove impurities, and then drying under reduced pressure to obtain polyimide powder. At this time, the weak solvent that can be used is a solvent that can precipitate polyimide and effectively remove impurities, as long as it is easy to dry. Examples include: water; alcohols such as methanol, ethanol, isopropyl alcohol, etc. , and these systems can be mixed. When the concentration of the polyimide solution added to a weak solvent and precipitated is too high, the precipitated polyimide will turn into particles, and impurities may remain in the coarse particles, or the resulting polyimide may be It is time-consuming to redissolve the amine powder in the solvent. On the other hand, when the concentration of the polyimide solution is too thin, a large amount of weak solvent is required, and waste solvent treatment may increase the environmental load or increase the manufacturing cost. Therefore, the concentration of the polyimide solution when added to the weak solvent is 20% by weight or less, more preferably 10% by weight or less. The amount of the weak solvent used at this time is preferably the same amount (weight basis) or more as the polyimide solution, preferably 1.5 times to 10 times by weight. The obtained polyimide powder is recovered and the residual solvent is removed by vacuum drying or hot air drying. The drying temperature and time are not limited as long as the polyimide does not deteriorate, for example, drying at a temperature of 30°C to 150°C for 3 hours to 24 hours.

When forming a polyimide film from the polyimide powder represented by the above-mentioned general formula (4) obtained in this way, it is necessary to temporarily dissolve the polyimide powder represented by the above-mentioned general formula (4) in a solvent and form Polyimide solution. Examples of solvent systems that can be used include the same solvents as the above-mentioned polymerization solvents, and include turpentine, mineral spirits, naphtha-based solvents, and the like. These solvents can be used alone, or two or more types can be used in combination. The polyimide powder can be dissolved in the air or in an inert gas at a temperature ranging from room temperature to below the boiling point of the solvent for 1 to 48 hours, and formed into a polyimide solution.

The polyimide solution obtained in this manner is poured onto a glass plate and heated in a vacuum, in an inert gas such as nitrogen, or in air, thereby obtaining a polyimide film (thin film). For example, the polyimide film can be obtained by drying in an oven, usually at 200°C to 400°C, preferably at 250°C to 350°C. Preferably, the polyimide film is produced in a vacuum or in an inert gas.

The chemical imidization reaction can also be performed by immersing the polyamide film formed on the substrate in a solution containing a dehydration cyclization reagent such as acetic anhydride in the presence of a tertiary amine such as pyridine or triethylamine. In this way, a polyimide film that is partially or almost completely imidized can also be produced, and then heat-treated as above to obtain a polyimide film.

The molecular weight of the polyimide represented by the above general formula (4) obtained by the above method is based on the weight average molecular weight, and is preferably 10,000 to 500,000, more preferably 10,000 to 300,000, and 20,000. To 200,000 is even better. If the molecular weight of polyimide is above 10,000, it is moldable and can easily maintain good mechanical properties. In addition, if the molecular weight of the polyimide is 500,000 or less, it is easy to control the molecular weight during synthesis, and it is often easy to obtain a solution with appropriate viscosity and easy to handle. In addition, the molecular weight of polyimide can be measured by a common method such as GPC method.

[Example]

Examples of the present invention are shown below, but the present invention is not limited thereto. In addition, the values shown in each Example/Comparative Example are values analyzed by the following analysis method.

[HPLC purity]

The area percentage value when HPLC measurement was performed under the following measurement conditions was taken as the purity of each compound described in the Examples.

<Measurement conditions for liquid chromatography>

Device: LC-20AD manufactured by Shimadzu Corporation

Column: L-column2 ODS (3μm, 4.6mmφ×150mm)

Mobile phase: Liquid A = 50% acetonitrile water (add 0.1% by volume formic acid)

Liquid B = acetonitrile (add 0.1% by volume formic acid)

Mobile phase gradient: Solution B concentration: 50% (0 minutes) → 100% (after 15 minutes) → 100% (after 25 minutes)

Flow rate: 1.0ml/min

Column temperature: 40℃, detection wavelength: UV254nm

[NMR measurement]

¹ H-NMR was recorded with a JEOL-ESC400 spectrometer using tetramethylsilane as the internal standard and deuterated dimethylsulfoxide (DMSO) as the solvent.

[LC-MS measurement]

LC-MS uses the following measurement conditions to perform separation, mass analysis, and identification of the target substance.

<LC-MS measurement conditions>

Device: "Xevo G2 Q-Tof" manufactured by Waters Co., Ltd.

Column: Made by CELI

×100mm) L-column2 ODS (2μm, 2.1mm

×100mm)

Tube string temperature: 40℃

Detection wavelength: UV 220-550nm

Mobile phase: Liquid A = 10mM ammonium acetate water, Liquid B = acetonitrile,

Liquid C = isopropyl alcohol

Mobile phase flow: 0.4ml/min

Mobile phase gradient: A/B/C=40/50/10→0/90/10 (5.21 minutes)

Detection method: Q-Tof

Ionization method: ESI(+)(-) method

Ion Source: Voltage (+) 2.0kV, temperature 120℃

Sampling Cone: Voltage 30V, gas flow 50L/h

Desolvation Gas: Temperature 400℃, gas flow 1200L/h

[Measurement of melting point]

Using TG-DTA (TG-DTA 8121/S manufactured by RIGAKU Co., Ltd.), the temperature was raised from room temperature to 500°C at a rate of 10°C/min under nitrogen flow, and the melting point (peak temperature of the maximum peak of melting endotherm) was measured.

[Solvent solubility]

1 part by weight of the diamine compound and 5 parts by weight of the following solvent were mixed, and the solvent solubility was evaluated based on the following evaluation criteria.

<Solvent>

‧NMP (N-methylpyrrolidone)

‧DMAc(N,N-Dimethylacetamide)

‧DMF(N,N-dimethylformamide)

<Evaluation criteria>

○: Dissolve at room temperature

△: It dissolves when heated and does not crystallize even when cooled.

×: It will dissolve if heated, but crystals will precipitate if cooled, or it will not dissolve even if heated.

[Measurement of 5% weight loss temperature]

Using TG-DTA (TG-DTA 8121/S manufactured by RIGAKU Co., Ltd.), the temperature was raised from room temperature to 500°C at a rate of 10°C/min under nitrogen flow, and the 5% weight loss temperature (T _d ⁵ under nitrogen, ℃).

[Measurement of glass transition temperature]

Measurement was performed using DMA (SII DMS-6100 (manufactured by Hitachi High-Tech Science Co., Ltd.)) in the tensile mode (heating rate 5°C/min, frequency 1Hz, temperature 40°C-350°C) and calculated from the maximum value of the loss modulus. Get the glass transition temperature (Tg, ℃).

[Measurement of linear thermal expansion coefficient]

Using a thermomechanical analysis device (TMA-7100 manufactured by Hitachi High-Tech Science Co., Ltd.), the load (static load) was set to film thickness (μm) × 0.5 g weight, and a polyimide film of 5 mm × 10 mm was heated to 150 °C, cool to 40 °C. The average of the slopes of the TMA curve from 100°C to 200°C obtained by running twice to 450°C at 5°C/min was defined as the coefficient of linear thermal expansion (CTE, ppm/K).

[Determination of specific dielectric constant and dielectric loss tangent]

Using a vector network analyzer (Vector Network Analyzer) (manufactured by Anritsu Co., Ltd., trade name; MS46122B) and a TE mode cavity resonator (manufactured by AET Co., Ltd.), the specific dielectric constant and Dielectric loss tangent. In addition, the material used for the measurement is left at a temperature of 24°C to 26°C and a relative humidity of less than 25% for 24 hours.

[Example 1] (Production example of dinitro compound represented by the above formula (2))

Put 245.62g (1.32mol) of 4-nitrobenzyl chloride and 400g of acetonitrile into a four-necked flask equipped with a stirrer, a thermometer and a reflux cooling tube, and cool to 0°C while stirring. Then, 100.01 g (0.60 mol) of tert-butylhydroquinone, 400.00 g of acetonitrile, and 104.71 g of pyridine (1.32 mol) were mixed and dissolved while stirring, and the mixture was added dropwise over 20 minutes at 0°C to 15°C. Then, the temperature was raised to 20°C, and the reaction temperature was maintained at 20°C to 25°C while stirring for 15 hours. After the reaction, the precipitated crystals were filtered and dried to obtain 275.28 g of white powder of the dinitro compound represented by the above formula (2) (HPLC purity 98.28%, physical yield 98.51%). The spectral values of ¹ H-NMR are as follows, and the measurement chart is shown in Fig. 1 .

[ ¹ H-NMR (dimethylsulfoxide-d6)]

δ(ppm)=8.47-8.37ppm(8H,m), 7.42-7.39(2H,m), 7.33(1H,dd), 1.32(9H,s).

[Example 2] (Production example of diamine represented by the above formula (1))

A four-necked flask with a hydrogen gas inlet pipe was charged with 40.01 g (0.09 mol) of the dinitro compound represented by formula (2) obtained in Example 1 and palladium/carbon powder containing 50% by weight of water (palladium content : 5% by weight based on dry weight) 0.80g and 400.01g of N,N-dimethylformamide were replaced with hydrogen in the reaction vessel. The temperature was raised to 80°C while stirring to dissolve the dinitro compound represented by the formula (2), and then the mixture was stirred at 80°C for 2 hours to react. After the reaction is completed, the palladium/carbon powder is removed by filtration, and the filtrate is cooled to room temperature and then dropped into a large amount of water to precipitate crystals. The precipitated crystals were filtered, washed with methanol, and dried in vacuum at 90° C. for 6 hours to obtain 32.99 g of gray powder of the diamine represented by the above formula (1) (HPLC purity 99.81%, physical yield 94.68%). The melting point (TG-DTA) is 295.2°C. In addition, the spectral values of ¹ H-NMR and LC-MS are as follows, and each measurement chart is shown in FIGS. 2 and 3 respectively. In addition, the results of the solvent solubility evaluation based on the above evaluation criteria are shown in Table 1.

[ ¹ H-NMR (dimethylsulfoxide-d6)]

δ(ppm)=7.82-7.78ppm(4H,m), 7.14-7.09(3H,m), 6.66-6.62(4H,m), 6.19-6.15(4H,m), 1.29(9H,s).

[LC-MS]

Mass spectrum value ([M+H] ⁺ ): 405.1822

(Calculated molecular weight (ESI ⁺ ; [C ₂₄ H ₂₄ N ₂ O ₄ +H] ⁺ ) of the diamine represented by the above formula (1): 405.1809).

[Comparative Example 1] (Compound represented by the above formula (8))

The solvent solubility of the compound represented by the above formula (8) (HPLC purity: 99.68%) was evaluated based on the above evaluation criteria. The results are presented in Table 1.

[Reference Example 1] (Compound represented by the following formula (9))

The solvent solubility of the compound represented by the following formula (9) (HPLC purity: 99.51%) was evaluated based on the above evaluation criteria. The results are presented in Table 1.

[Table 1]

[Example 3] (Example of production of polyamide having a repeating unit represented by the above general formula (3) and polyimide having a repeating unit represented by the above general formula (4))

6.08 g (15.00 mmol) of the diamine represented by the above formula (1) obtained in Example 2 was dissolved in 24.46 g of dehydrated N-methylpyrrolidone (hereinafter, sometimes referred to as "NMP"). Then, 4.41 g (15.00 mmol) of biphenyl-3,4,3',4'-tetracarboxylic dianhydride (hereinafter, sometimes referred to as "BPDA") was gradually added (total solute concentration: 30% by weight) ) and stirred at room temperature for 24 hours. The viscosity increased and stirring became difficult. Therefore, dehydrated NMP was appropriately added while stirring for another 48 hours to obtain a polyamide having a repeating unit represented by the above general formula (3). Solution (final solute concentration: 18.53 wt%). Then, the obtained polyamic acid solution was coated on a glass plate, heated at 80°C for 3 hours to obtain a polyamic acid film, and then heated at 250°C for 1 hour and 300°C for 1 hour. Thermal imidization. Then, in order to remove residual stress, the film was peeled off from the glass substrate and heated at 310° C. for 1 hour to obtain a polyimide film having a repeating unit represented by the above general formula (4). For the obtained polyimide film, the glass transition temperature, 5% weight loss temperature, linear thermal expansion coefficient, specific dielectric constant and dielectric loss tangent were measured. The measurement results are presented in Table 2.

[Reference Example 2] (Polyimide obtained from the diamine represented by the above formula (8) and BPDA)

1.05g (3.00mmol) of the diamine represented by the above formula (8) was added to 7.71g of dehydrated NMP, and the mixture was stirred at room temperature for a while, but it was not completely dissolved. Here, the diamine was dissolved by heating to 95°C, and then 0.88g (3.00mmol) of BPDA was slowly added while heating at 95°C (total solute concentration: 30% by weight), and then cooled to room temperature and reacted for 2 hours. The viscosity increased and stirring became difficult, so dehydrated NMP was used to dilute to 15.15% by weight, and stirring was continued to obtain a polyamic acid solution (a total of 72 hours of stirring were carried out after adding BPDA until polyamic acid was obtained). The obtained polyamide solution was coated on a glass plate, heated at 80°C for 3 hours to form a polyamide film, and then heated at 250°C for 1 hour and 300°C for 1 hour. Perform thermal imidization. Ran Then, in order to remove residual stress, it was peeled off from the glass substrate and heated at 310° C. for 1 hour to obtain a polyimide film. For the obtained polyimide film, the glass transition temperature, 5% weight loss temperature, linear thermal expansion coefficient, specific dielectric constant and dielectric loss tangent were measured. The measurement results are presented in Table 2.

[Reference Example 3] (Polyimide obtained from the diamine represented by the above formula (9) and BPDA)

Except that 3.62 g (10.00 mmol) of the diamine represented by the above formula (9) was used instead of the diamine represented by the above formula (8), the same operation as Reference Example 2 was performed to obtain a polyimide film. For the obtained polyimide film, the glass transition temperature, 5% weight loss temperature, linear thermal expansion coefficient, specific dielectric constant and dielectric loss tangent were measured. The measurement results are presented in Table 2.

[Reference Example 4] (Polyimide obtained from the diamine represented by the following formula (10) and BPDA)

Except that 0.69 g (1.50 mmol) of the diamine represented by the above formula (10) was used instead of the diamine represented by the above formula (8), the same operation as in Reference Example 2 was performed to obtain a polyimide film. For the obtained polyimide film, the glass transition temperature, 5% weight loss temperature, linear thermal expansion coefficient, specific dielectric constant and dielectric loss tangent were measured. The measurement results are presented in Table 2.

[Table 2]

Claims (9)

A diamine represented by the following formula (1),

A method for producing the diamine according to claim 1, which is to reduce the dinitro compound represented by the following formula (2),

A dinitro compound represented by the following formula (2),

A polyamide having repeating units represented by the following general formula (3),

In the formula, A represents a tetravalent aromatic group or a tetravalent aliphatic group. A polyimide having repeating units represented by the following general formula (4),

In the formula, A represents a tetravalent aromatic group or a tetravalent aliphatic group. A polyamide solution containing the polyamide described in claim 4 and a solvent. A film containing the polyamide according to claim 4. A film containing the polyimide described in claim 5. A laminated body having a layer containing the polyimide according to claim 5.

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