JP2010254838A - Curable resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermosetting resin composition producing a cured article having curability at low temperature and heat resistance, and to provide a cured article obtained by curing the same. <P>SOLUTION: The thermosetting resin composition includes a particular cyanic acid ester compound, an epoxy resin, a metal catalyst and a particular amine compound. The cured article is obtained by curing the thermosetting resin composition. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a novel one-component curable resin composition. Such a curable resin composition is excellent in fluidity, heat resistance and storage stability, and suitable for sports applications such as golf shafts, fishing rods, and other general industrial applications, including structural materials for aircraft and railway vehicles. Resin compositions corresponding to the matrix of applicable fiber reinforced composite materials can be used, as well as electrical insulating materials, resist resins, semiconductor sealing resins, printed wiring board adhesives, electrical laminates, and prepregs. It can be used for a wide range of applications such as matrix resin, build-up laminate material, fiber reinforced plastic resin, liquid crystal display panel sealing resin, liquid crystal color filter resin, paint, various coating agents, adhesives, etc. .

  In recent years, with the expansion of applications of fiber reinforced composite materials, fiber reinforced composite materials are required to have physical properties such as high strength, high elastic modulus, high heat resistance, high moisture resistance, and flame resistance. A fiber reinforced composite material is manufactured by various methods. Resin Transfer Molding (RTM) is obtained by injecting a liquid thermosetting resin into a mold in which a reinforced fiber base material is disposed and heat-curing to obtain a fiber reinforced composite material. Is a method with excellent productivity. In particular, the method of injecting a thermosetting resin by depressurizing the inside of a mold with a vacuum pump is called Vacuum Assisted Resin Transfer Molding (VaRTM), and is attracting attention as a low-cost molding method. ing.

  As matrix resins generally used for fiber reinforced composite materials, thermosetting resins such as phenol resins, melamine resins, bismaleimide resins, unsaturated polyester resins, cyanate ester resins, and epoxy resins are used depending on the application. However, in terms of heat resistance, high elastic modulus, and high moisture resistance, cyanate ester-epoxy resins are excellent and are preferably used. From the above background, a cyanate ester-epoxy resin composition that is liquid at room temperature and has high heat resistance, high elastic modulus, and high moisture resistance when cured is desired.

  In general, in order to cure a cyanate ester-epoxy resin, it is necessary to cure at a high temperature of 200 ° C. or higher. (See, for example, Patent Document 1) Such high-temperature curing conditions are not preferable because they are not economically superior in molding large composite structures such as aircraft wings, fuselage, and railway vehicles. As an improvement, examples using amine curing agents such as dicyandiamide and dihydrazide have also been proposed (see, for example, Patent Document 2). Primary and secondary amines having active hydrogen react with glycidyl groups at room temperature. Therefore, when these curing agents are used, sufficient storage stability cannot be obtained.

  On the other hand, an example of using a latent cured product obtained by reacting an amine compound having a specific structure, a polyamine compound having two or more amino groups in the molecule, an organic polyisocyanate compound, or an epoxy compound has been proposed. However, in this case, the glass transition point is measured for a sample cured at a high temperature of 300 ° C., and there is no mention of compatibility between low temperature curing and high heat resistance.

  Although the composition of the combined use of a metal complex catalyst, a bisphenol compound, and imidazole is disclosed (see, for example, Patent Document 4), in this case, the bisphenol used is one that melts near the curing temperature, or the epoxy resin and cyanate resin at room temperature. It is described that it is desirable to be slightly soluble. Therefore, the composition does not become a uniform solution and cannot be said to be suitable for the RTM method. Moreover, although the combined composition of a metal chelating agent and an acid anhydride is disclosed as a curing agent (see, for example, Patent Document 5), further reduction of the curing temperature and improvement in heat resistance of the cured product are required.

Japanese Patent Laid-Open No. 08-283409 JP 2001-302767 A JP 2009-13205 A Japanese Patent Laid-Open No. 11-106481 JP 2000-336245 A

  An object of the present invention is to provide a curable resin composition that is liquid at room temperature and can be cured at low temperature.

  As a result of intensive studies, the present inventors have found that the cyanide ester represented by the following formula (1), the epoxy resin, the metal complex catalyst, and the conjugate acid have a pKa of 5.0 or more and 12.0 or less on the nitrogen atom. The inventors have found that a curable resin composition comprising an amine compound having no active hydrogen has excellent low-temperature curability and heat resistance, and has completed the present invention. That is, the present invention is as follows.

（式中Ｒ１とＲ２は異なる基であって、Ｒ１は水素または炭素数１〜４のアルキル基、Ｒ２は炭素数１〜４のアルキル基を示す。） 1. (A) 100 parts by weight of a cyanate ester represented by the following formula (1), which is an amorphous liquid at 50 ° C., (B) 20 to 250 parts by weight of an epoxy resin, (C) a metal complex catalyst, and (D) A curable resin composition that is liquid at 50 ° C., comprising an amine compound having a pKa of a conjugate acid of 5.0 to 12.0 and having no active hydrogen on a nitrogen atom.

(Wherein R1 and R2 are different groups, R1 represents hydrogen or an alkyl group having 1 to 4 carbon atoms, and R2 represents an alkyl group having 1 to 4 carbon atoms.)

  2. (A) The cyanate ester is 1,1-bis (4-cyanatophenyl) ethane, 2,2-bis (4-cyanatophenyl) butane, 1,1-bis (4-cyanatophenyl) isobutane and 2 The curable resin composition according to the above item 1, which is at least one selected from the group consisting of 2, bis (4-cyanatophenyl) -4-methylpentane.

  3. (D) The curable resin composition according to the above item 1 or 2, wherein the amine compound has a tertiary amino group and has a boiling point of 120 ° C. or higher at normal pressure.

  4). (D) The curable resin composition according to the above item 1 or 2, wherein the amine compound has a pyridine skeleton or a quinoline skeleton, and has a boiling point of 120 ° C. or higher at normal pressure.

  5. (D) The curable resin according to the above item 1 or 2, wherein the amine compound is one or more selected from the group consisting of 2-dimethylaminoethanol, 4-dimethylaminopyridine and 2,6-lutidine. Composition.

  6). (B) The curable resin composition according to any one of Items 1 to 5, wherein the epoxy resin is liquid at 50 ° C.

  7). (B) In the first to fifth items, the epoxy resin is at least one selected from the group consisting of a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a phenol novolac type epoxy resin, and a dihydroxynaphthalene type epoxy resin. The curable resin composition described.

  8). (C) The curable resin composition according to any one of Items 1 to 7, wherein the metal complex catalyst is a metal carboxylate or a metal acetylacetonate complex.

  9. (C) Curable resin composition of said 1st-8th item whose metal complex catalyst is 0.01-0.1 weight part with respect to 100 weight part of (A) cyanate ester resin.

10. (D) Curable resin composition of said 1st-9th item whose amine compound is 0.05-1.0 weight part with respect to 100 weight part of (B) epoxy resins.

11. Hardened | cured material formed by hardening | curing the composition described in said 1st-10th item | term.

12. Hardened | cured material of the said 11th item formed by thermosetting at the temperature of 180 degrees C or less.

13. Hardened | cured material of the said 11th item formed by thermosetting at the temperature of 160 degrees C or less.

The curable resin composition of the present invention is liquid at room temperature, has low temperature curability and high heat resistance, and thus is extremely useful as a high-functional polymer material, and has excellent thermal, electrical and mechanical properties. In addition to electrical insulating materials, adhesives, laminated materials, resists, build-up laminated board materials as materials, fixing materials in the fields of civil engineering / architecture, electricity / electronics, automobiles, railways, ships, aircraft, sports equipment, arts and crafts, etc. It is preferably used for structural members, reinforcing agents, molding materials and the like. Among these, a wide range of applications such as aircraft structural members, satellite structural members and railway vehicle structural members that require weather resistance, flame resistance and high mechanical strength, fiber reinforced composite materials for sports, that is, golf club shafts, fishing rods, etc. Can be used for

1H-NMR spectrum of 1,1-bis (4-cyanatophenyl) ethane 1H-NMR spectrum of 2,2-bis (4-cyanatophenyl) butane 1H-NMR spectrum of 1,1-bis (4-cyanatophenyl) isobutane 1H-NMR spectrum of 2,2-bis (4-cyanatophenyl) -4-methylpentane

  In the present invention, (A) a cyanate ester represented by formula (1), which is an amorphous liquid at 50 ° C., (B) an epoxy resin, (C) a metal complex catalyst, and (D) a pKa of a conjugate acid It is a curable resin composition that is liquid at 50 ° C. and contains an amine compound that is 5.0 or more and 12.0 or less and has no active hydrogen on a nitrogen atom. In this composition, (A) 40 to 250 parts by weight of (B) epoxy resin, (C) metal complex catalyst, (D) pKa of conjugate acid with respect to 100 parts by weight of cyanate ester compound represented by formula (1) Is not less than 5.0 and not more than 12.0, and it is essential to contain an amine compound having no active hydrogen on the nitrogen atom, but if it is liquid at room temperature, a cyanate ester compound other than the component (A), an oxetane resin It is also possible to add a compound having a polymerizable unsaturated group and / or the like.

The cyanate ester represented by the formula (1) used in the present invention is a group in which R1 and R2 are different, R1 is hydrogen or an alkyl group having 1 to 4 carbon atoms, and R2 is a group having 1 to 4 carbon atoms. An alkyl group is meant. These cyanate esters are non-crystalline liquids having a low viscosity at 50 ° C., and their viscosity is 20 to 10,000 cP at 25 ° C. Examples of cyanate esters of formula (1) include 1,1-bis (4-cyanatophenyl) ethane, 1,1-bis (4-cyanatophenyl) propane, 1,1-bis (4-silane). Anatophenyl) butane, 1,1-bis (4-cyanatophenyl) isobutane, 1,1-bis (4-cyanatophenyl) pentane, 1,1-bis (4-cyanatophenyl) -3-methylbutane, 1,1-bis (4-cyanatophenyl) -2-methylbutane, 1,1-bis (4-cyanatophenyl) -2,2-dimethylpropane, 2,2-bis (4-cyanatophenyl) butane 2,2-bis (4-cyanatophenyl) pentane, 2,2-bis (4-cyanatophenyl) hexane, 2,2-bis (4-cyanatophenyl) -3-methylbutane, 2,2- Bis (4-cyanatofe ) -4-methylpentane, 2,2-bis (4-cyanatophenyl) -3-methylpentane, 2,2-bis (4-cyanatophenyl) -3,3-dimethylbutane, 3,3- Bis (4-cyanatophenyl) hexane, 3,3-bis (4-cyanatophenyl) heptane, 3,3-bis (4-cyanatophenyl) octane, 3,3-bis (4-cyanatophenyl) 2-methylpentane, 3,3-bis (4-cyanatophenyl) -2-methylhexane, 3,3-bis (4-cyanatophenyl) -2,2-dimethylpentane, 4,4-bis ( 4-cyanatophenyl) -3-methylheptane, 3,3-bis (4-cyanatophenyl) -2-methylheptane, 3,3-bis (4-cyanatophenyl) -2,2-dimethylhexane, 3,3-bis (4-si Natophenyl) -2,4-dimethylhexane, 3,3-bis (4-cyanatophenyl) -2,2,4-trimethylpentane, and 1,1-bis (4-cyanatophenyl) ethane; , 1-bis (4-cyanatophenyl) propane, 1,1-bis (4-cyanatophenyl) butane, 1,1-bis (4-cyanatophenyl) isobutane, 2,2-bis (4-si Anatophenyl) butane, 2,2-bis (4-cyanatophenyl) hexane, 2,2-bis (4-cyanatophenyl) -4-methylpentane, 2,2-bis (4-cyanatophenyl)- 3,3-dimethylbutane, 3,3-bis (4-cyanatophenyl) hexane, 3,3-bis (4-cyanatophenyl) -2-methylpentane are preferred, and 1,1-bis (4-si Anatophenyl) More preferred are 1,1-bis (4-cyanatophenyl) isobutane, 2,2-bis (4-cyanatophenyl) butane, and 2,2-bis (4-cyanatophenyl) -4-methylpentane. .

  The cyanate ester compound of component (A) can be obtained by derivatizing phenol having a corresponding structure to a cyanate ester. As a method for cyanating phenol, IAN HAMERTON, “Chemistry and Technology of Cyanate Esters Resins”, BLACKIE ACADEMIC & PROFESSIONAL describes a general method for synthesizing cyanate compounds. In addition, US Pat. No. 3,553,244 provides a method of reacting in a solvent so that cyan halide is always present in excess in the presence of a base in a solvent. JP-A-7-53497 discloses a tertiary as a base. A method of synthesizing using amine and using it in excess of cyan chloride is disclosed in JP-T-2000-501138, and a method of reacting trialkylamine and cyanogen halide in a continuous plug flow method is disclosed in JP-T-2001. JP-A-504835 discloses a method of treating a tert-ammonium halide as a by-product with a cation and an anion exchange pair when a phenol and a cyanogen halide are reacted in a non-aqueous solution of tert-amine. In addition, in Patent No. 291054, a tertiary amine and a cyanogen halide are simultaneously added and reacted in the presence of a solvent capable of separating a phenol compound from water, followed by washing with water and separation from the resulting solution. A method for precipitation purification using a poor solvent for tertiary alcohols and hydrocarbons is disclosed in Japanese Patent Application Laid-Open No. 2007-277102. Naphthols, cyanogen halides, and tertiary amines are mixed in two phases, water and an organic solvent. A process for producing a cyanate ester characterized by reacting under acidic conditions in a system solvent is described.

  Usually, as a synthesis procedure of a cyanate ester, a phenol compound is dissolved in an organic solvent, a basic compound such as a tertiary amine is added, and then reacted with an excess of cyanogen halide. In this system, since cyan halide is always present in excess, it is said that imidocarbonate produced by reaction of phenolate anion with cyanate ester can be suppressed. However, since excess cyanogen halide and tertiary amine react to produce dialkylcyanamide, the reaction temperature must be kept at 10 ° C. or lower, preferably 0 ° C. or lower, more preferably −10 ° C. or lower.

  In addition to the above method, the order of pouring in the reaction can be arbitrarily selected. For example, after a phenol compound is dissolved in a solvent, a basic compound such as a tertiary amine and a cyanogen halide or a solution thereof may be dropped alternately or simultaneously. Further, a mixed solution of a phenol compound and a basic compound such as a tertiary amine and a cyanogen halide or a solution thereof can be simultaneously supplied. In either case, the reaction is a large exothermic reaction, but it is necessary to keep the reaction temperature at 10 ° C. or lower, preferably 0 ° C. or lower, more preferably −10 ° C. or lower for the purpose of suppressing side reactions.

  Any form of the reaction can be used, and the reaction may be performed in a batch system, a semi-batch system, or a continuous flow system.

  A basic compound such as a tertiary amine and a cyanogen halide are added in an amount of 0.1 to 8 times mol, preferably 1 to 5 times mol to the phenolic hydroxyl group of the phenol compound, and reacted. In particular, when there is a sterically hindered substituent at the ortho position of the hydroxyl group, the basic compound such as a tertiary amine and the required amount of cyanogen halide are increased as compared with the case where no substituent is present. As the cyanide halide to be used, cyan chloride, cyanogen bromide and the like can be used. As the basic compound to be used, either an organic base or an inorganic base may be used, but when an organic solvent is used, an organic base having high solubility is preferable. Of these, tertiary amines with few side reactions are preferred. The tertiary amine may be any of alkylamine, arylamine, and cycloalkylamine, specifically, trimethylamine, triethylamine, methyldiethylamine, tripropylamine, tributylamine, methyldibutylamine, dinonylmethylamine, dimethylstearylamine, Examples include dimethylcyclohexylamine, diethylaniline, pyridine, and quinoline.

  Solvents used in the reaction include ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, aromatic solvents such as benzene, toluene, and xylene, diethyl ether, dimethyl cellosolve, diglyme, tetrahydrofuran, methyltetrahydrofuran, dioxane, and tetraethylene. Ether solvents such as glycol dimethyl ether, halogenated hydrocarbon solvents such as methylene chloride, chloroform, carbon tetrachloride, chlorobenzene, alcohol solvents such as methanol, ethanol, isopropanol, methylsolvosolve, propylene glycol monomethyl ether, N, N -Aprotic polar solvents such as dimethylformamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidone, dimethyl sulfoxide; Nitrile solvents such as nitrile and benzonitrile, nitro solvents such as nitromethane and nitrobenzene, ester solvents such as ethyl acetate and ethyl benzoate, and hydrocarbon solvents such as cyclohexane can be used. 1 type or 2 types or more can be used in combination.

  As a post-treatment after the reaction, the hydrogen chloride salt of a basic compound such as a tertiary amine produced as a by-product is usually filtered or removed by washing with water. On the other hand, when a solvent miscible with water is used, the obtained reaction solution is poured into water and then extracted with an organic solvent immiscible with water, or the precipitated crystals are collected by filtration. Can be obtained. Moreover, in order to remove excess amines in the washing | cleaning process, the method of using acidic aqueous solutions, such as a thin hydrochloric acid, is also taken. In order to remove water from the sufficiently washed reaction solution, a drying operation can be performed using a general method such as sodium sulfate or magnesium sulfate.

  After these operations, concentration and, in some cases, distillation purification are performed. At the time of concentration and distillation purification, since the cyanate ester compound has an unstable structure, a method of reducing the pressure while suppressing the temperature to 150 ° C. or lower is employed.

  As the epoxy resin as component (B), generally known epoxy resins can be used. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, biphenyl type epoxy resin, dihydroxynaphthalene type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, xylene novolac type epoxy resin, triglycidyl isocyanurate, alicyclic And epoxy resin, dicyclopentadiene novolac epoxy resin, biphenyl novolac epoxy resin, phenol aralkyl novolac epoxy resin, and naphthol aralkyl novolac epoxy resin. These epoxy resins can be used alone or in combination.

  Even if these epoxy resins are solid, they can be used as long as they can be made into a liquid resin composition at 50 ° C. by using another cyanate ester or epoxy resin together. The epoxy resin is preferably a liquid epoxy resin at a temperature, and more preferably a liquid epoxy resin at room temperature. Specific examples of epoxy resins that are liquid at normal temperature include “Epicoat 828 (manufactured by Japan Epoxy Resin Co., Ltd.)”, “Epicoat 815 (same)”, and “Epicron 840 (DIC Corporation)”. Etc.) are "Epicoat 806 (Japan Epoxy Resin Co., Ltd.)", "Epicoat 807 (same)", "Epicron S-129 (DIC Corporation)", "Epicron" "830 (same as above)", "Epicoat 152 (manufactured by Japan Epoxy Resin Co., Ltd.)" as the phenol novolac type epoxy resin, and "Epiclon HP-4032 (manufactured by DIC Corporation)" as the dihydroxynaphthalene type epoxy resin. Or the like.

  The ratio of the component (A) to the component (B) is preferably 20 to 250 parts by weight of the component (B) with respect to 100 parts by weight of the component (A). The cyanate ester and the epoxy resin each react and cure independently, but the cured product of the cyanate ester alone has high elasticity and therefore lacks toughness, and the cured product of the epoxy resin alone lacks heat resistance. However, when a cyanate ester and an epoxy resin are used in combination, these competitive reactions occur in parallel, and an oxazolidine ring can be formed, making it possible to achieve both toughness and heat resistance.

  As the metal complex catalyst of the component (C), generally known catalysts can be used. For example, there are metal naphthenates such as cobalt, zinc, chromium, copper, iron, manganese, nickel, and titanium, acetylacetonates, salts of derivatives thereof, and organic acid salts such as various carboxylate alkoxides. You may mix and use. Moreover, it is preferable that the usage-amount of the metal complex catalyst of (C) component is 0.01 to 0.1 weight part with respect to 100 weight part of cyanate ester of (A) component. If it is less than 0.01 parts by weight, the reaction promoting effect is low, and the curing time may be long. On the other hand, if it exceeds 0.1 parts by weight, the usable time and the shelf life of the product may be impaired. For the above reasons, the amount of the component (C) metal complex catalyst used is more preferably 0.015 parts by weight to 0.08 parts by weight with respect to 100 parts by weight of the component (A) cyanate ester, and 0.02 parts by weight. To 0.075 parts by weight is more preferable.

  The amine compound having no active hydrogen on the nitrogen atom of component (D) preferably has a pKa of the conjugate acid of 5.0 or more and 12.0 or less. If it is lower than 5.0, sufficient catalytic action cannot be obtained, low temperature curability is impaired, and it is difficult to obtain sufficient physical properties of the cured product. On the other hand, if it is higher than 12.0, the reactivity is too high and the curing partially proceeds at room temperature, so that the storage stability cannot be ensured. For the above reasons, the pKa of the conjugate acid is more preferably from 7.0 to 12.0, and even more preferably from 8.0 to 11.0. The amount of the amine compound having no active hydrogen on the nitrogen atom of the component (D) is preferably 0.05 to 1.0 part by weight with respect to 100 parts by weight of the epoxy resin of the component (B). . If the amount is less than 0.05 parts by weight, the reaction promoting effect is low and the curing time may be long. On the other hand, if it exceeds 1.0 part by weight, the pot life and the shelf life of the product may be impaired. For the above reasons, the amount of the metal complex catalyst used as the component (D) is more preferably 0.15 parts by weight to 0.8 parts by weight with respect to 100 parts by weight of the epoxy resin as the component (B). 0.75 part by weight is more preferable.

  The amine compound having no active hydrogen on the nitrogen atom of component (D) is preferably one having a high boiling point in order to control the vacuum defoaming step and the dissipation during curing. Specifically, the boiling point of the amine compound having no active hydrogen on the nitrogen atom of component (D) is preferably 120 ° C. or higher at normal pressure, more preferably 130 ° C. or higher, and 150 ° C. or higher. More desirable. As an amine compound having no active hydrogen on the nitrogen atom of the component (D), a compound having a certain degree of polarity is more excellent because the compatibility with the resin is enhanced and the reaction promoting effect is enhanced.

  As the amine compound having no active hydrogen on the nitrogen atom of component (D), any aliphatic amine or aromatic amine can be used as long as it does not have active hydrogen on the nitrogen atom. For example, N, N-dimethyldodecylamine, N, N-dimethylhexadecylamine, N, N-dimethyloctadecylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, N, N-dimethylcyclohexylamine, N, N-dimethylcyclohepentylamine, N, N-dicyclohexylmethylamine, 2- (diisopropylamino) ethanol, 2-dimethylaminoethanol, 3-dimethylamino-1-propanol 4-dimethylamino -1-butanol, 6-dimethylamino-1-hexanol, 8-dimethylamino-1-octanol, N-tert-butyldiethanolamine, 2-dibutylaminoethanol, 2- (2-diethylaminoethoxy) ethanol, 2- (diethylamino) ) Etano , 3- (diethylamino) -1-propanol, 2- [2-dimethylamino] ethoxy] ethanol, N, N-dimethyl-n-octylamine, N, N-dimethyldecylamine, N, N-dimethyltetradecyl Amine, N-ethyldiethanolamine, N-methyldiethanolamine, 1-methyl-3-piperidinemethanol, 1-methyl-2-piperidinemethanol, 4-hydroxy-1-methylpiperidine, 1-piperidineethanol, 1-piperidinepentanol, N-butyldiethanolamine, bis (2-hydroxyethyl) aminotris (hydroxymethyl) methane, N, N, N ′, N ″, N ″ -pentakis (2-hydroxypropyl) diethylenetriamine, N, N, N ′ , N ″, N ″ -pentamethyldiethyleneate Reamine, N, N, N ′, N′-tetramethyl 1,6-diaminohexane, N, N, N ′, N′-tetramethyl 1,4-diaminobutane, 2,6,10-trimethyl-2, 6,10-triazaundecane, bis (2-dimethylaminoethyl) disulfide, 1,4-diazabicyclo [2,2,2] octane, 2-dimethylaminoethanethiol, 2-diethylaminoethanethiol, quinuclidine, 3-quinuclidinol 3-quinuclidinone, triethanolamine, 8-mercaptoquinoline, 6,6′-dimethyl-2,2′-bipyridyl, 4,4′-dimethyl-2,2′-bipyridyl, cinchonidine, 4-dimethylaminopyridine, 2-dimethylaminopyridine, 4,4′-dipyridyl sulfide, di-2-pyridyl ketoxime, 2,6- Lutidine, 2,4,6-collidine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 4-pyrrolidinopyridine, 4- (4-pyridyl) morpholine and the like, 2- (diisopropylamino) Ethanol, 2-dimethylaminoethanol, 3-dimethylamino-1-propanol, 4-dimethylamino-1-butanol, N-tert-butyldiethanolamine, 2-dibutylaminoethanol, 2- (2-diethylaminoethoxy) ethanol, 2 -(Diethylamino) ethanol, 3- (diethylamino) -1-propanol, 2- [2-dimethylamino] ethoxy] ethanol, N, N-dimethyl-n-octylamine, N-ethyldiethanolamine, N-methyldiethanolamine, 1 -Methyl-3-piperidine Methanol, 1-methyl-2-piperidinemethanol, 4-hydroxy-1-methylpiperidine, 1-piperidineethanol, 1-piperidinepentanol, 1,4-diazabicyclo [2,2,2] octane, 2-dimethylaminoethane Thiol, 2-diethylaminoethanethiol, quinuclidine, 3-quinuclidinol, 3-quinuclidinone, triethanolamine, cinchonidine, 4-dimethylaminopyridine, 2-dimethylaminopyridine, 2,6-lutidine, 2,4,6-collidine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 4-pyrrolidinopyridine, 4- (4-pyridyl) morpholine are preferred, 2-dimethylaminoethanol, 3-dimethylamino-1-propanol, N-tert -Butyldietano Ruamine, 2- (diethylamino) ethanol, 3- (diethylamino) -1-propanol, 1-methyl-3-piperidinemethanol, 1-methyl-2-piperidinemethanol, 4-hydroxy-1-methylpiperidine, 1-piperidineethanol 1,4-diazabicyclo [2,2,2] octane, 2-dimethylaminoethanethiol, quinuclidine, 3-quinuclidinol, 3-quinuclidinone, cinchonidine, 4-dimethylaminopyridine, 2-dimethylaminopyridine, 2,6- Rutidine, 2,4,6-collidine, and 4- (4-pyridyl) morpholine are more preferable, and 2-dimethylaminoethanol, 4-dimethylaminopyridine, and 2,6-lutidine are more preferable.

  As the cyanate ester compound other than the component (A), generally known compounds can be used. For example, bisphenol A dicyanate, bisphenol F dicyanate, bisphenol P dicyanate, bisphenol Z dicyanate, 4,4 ′-(α-methylbenzylidene) bisphenol dicyanate, bisphenol fluorenediocyanate, phenol novolac cyanate, cresol novolac cyanate, dicyclo Pentadiene novolac-type cyanate, tetramethylbisphenol F dicyanate, biphenol dicyanate, 4,4 ′-(3,3,5-trimethylcyclohexylidene bisphenol dicyanate, bis (4-cyanatophenyl) ether, bis (4-si Anatophenyl) thioether, etc. These cyanate ester compounds can be used alone or in combination.

  As the oxetane resin, generally known oxetane resins can be used. For example, oxetane, 2-methyloxetane, 2,2-dimethyloxetane, 3-methyloxetane, alkyloxetane such as 3,3-dimethyloxetane, 3-methyl-3-methoxymethyloxetane, 3,3′-di (tri Fluoromethyl) perfluoxetane, 2-chloromethyloxetane, 3,3-bis (chloromethyl) oxetane, OXT-101 (trade name, manufactured by Toagosei Co., Ltd.), OXT-121 (trade name, manufactured by Toagosei Co., Ltd.), etc. Is mentioned. These oxetane resins can be used alone or in combination.

  As the compound having a polymerizable unsaturated group, generally known compounds can be used. For example, vinyl compounds such as ethylene, propylene, styrene, divinylbenzene, divinylbiphenyl, methyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, polypropylene glycol di (meth) acrylate, Mono- or polyhydric alcohol (meth) acrylates such as trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol Epoxy (meth) acrylates such as A-type epoxy (meth) acrylate and bisphenol F-type epoxy (meth) acrylate, benzocyclobutene resin, (bis) male Mid resin etc. are mentioned. These compounds having an unsaturated group can be used alone or in combination.

  When using the compound which has a polymerizable unsaturated group, a well-known polymerization initiator can be used as needed. As the polymerization initiator, generally known polymerization initiators can be used. For example, peroxides such as benzoyl peroxide, p-chlorobenzoyl peroxide, di-t-butyl peroxide, diisopropyl peroxycarbonate, di-2-ethylhexyl peroxycarbonate, or azo such as azobisisobutyronitrile Compounds and the like.

  The curable resin composition of the present invention obtained by the above-described method can be cured by heat. The curing temperature is preferably in the range of 60 ° C. or higher and 300 ° C. or lower. If the curing temperature is too low, curing does not proceed. If the curing temperature is too high, the cured product itself may deteriorate or heat may be exerted on other members to be connected. Furthermore, when applied to molding large composite structures such as aircraft wings, fuselage, and railway vehicles, the curing temperature is preferably lower. For the above reasons, the range of 80 ° C. or higher and 200 ° C. or lower is more preferable, the range of 100 ° C. or higher and 180 ° C. or lower is more preferable, and the range of 120 ° C. or higher and 160 ° C. or lower is even more preferable.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not particularly limited to the following examples.

(I) Synthesis of cyanate ester Synthesis Example 1
Synthesis of 1,1-bis (4-cyanatophenyl) ethane 100 mmol of 1,1-bis (4-hydroxyphenyl) ethane (manufactured by Wako Pure Chemical Industries, Ltd.) and 280 mmol of triethylamine were dissolved in 100 mL of tetrahydrofuran (Solution 1) ) Solution 1 was added dropwise over 1.5 hours at −10 ° C. to a mixture of 46.2 g of 300 mmol of methylene chloride solution of cyanogen chloride and 100 mL of tetrahydrofuran. When the completion of the reaction was confirmed, the reaction solution was concentrated, and the resulting crude product was dissolved in 300 mL of methylene chloride. This was washed with 1M hydrochloric acid and distilled water, and dried over anhydrous magnesium sulfate. By distilling off methylene chloride, 23.1 g of the target 1,1-bis (4-cyanatophenyl) ethane was obtained. The resulting cyanate ester was liquid at 50 ° C. The structure was identified by NMR spectrum.
1H-NMR: (270 MHz, chloroform-d, internal standard TMS)
δ (ppm)
1.62 (d, 3H), 4.22 (q, 1H), 7.42 (complex, 8H)

Synthesis example 2
Synthesis of 2,2-bis (4-cyanatophenyl) butane 2,2-bis (4-hydroxyphenyl) butane (manufactured by Tokyo Chemical Industry Co., Ltd.) instead of 1,1-bis (4-hydroxyphenyl) ethane Was carried out in the same manner as in Synthesis Example 1 except that 29.4 g of 2,2-bis (4-cyanatophenyl) butane was obtained. The resulting cyanate ester was liquid at 50 ° C. The structure was identified by NMR spectrum.
1H-NMR: (270 MHz, chloroform-d, internal standard TMS)
δ (ppm)
0.73 (t, 3H), 1.61 (s, 3H), 2.14 (q, 2H), 7.22 (complex, 8H)

Synthesis example 3
Synthesis of 1,1-bis (4-cyanatophenyl) isobutane 1,1-bis (4-hydroxyphenyl) isobutane (Wako Pure Chemical Industries, Ltd.) instead of 1,1-bis (4-hydroxyphenyl) ethane ) Was used in the same manner as in Synthesis Example 1 to obtain 28.3 g of 1,1-bis (4-cyanatophenyl) isobutane. The resulting cyanate ester was liquid at 50 ° C. The structure was identified by NMR spectrum.
1H-NMR: (270 MHz, chloroform-d, internal standard TMS)
δ (ppm)
0.88 (d, 6H), 2.41 (m, 1H), 3.51 (d, 1H), 7.20-7.35 (complex, 8H)

Synthesis example 4
Synthesis of 2,2-bis (4-cyanatophenyl) -4-methylpentane 2,2-bis (4-hydroxyphenyl) -4-methylpentane instead of 1,1-bis (4-hydroxyphenyl) ethane Except having used (Tokyo Chemical Industry Co., Ltd.), it implemented similarly to the synthesis example 1, and obtained 31.7g of 2, 2-bis (4-cyanatophenyl) -4-methylpentane. The resulting cyanate ester was liquid at 50 ° C. The structure was identified by NMR spectrum.
1H-NMR: (270 MHz, chloroform-d, internal standard TMS)
δ (ppm)
0.73 (d, 6H), 1.53 (m, 1H), 2.05 (s, 3H), 7.18-7.26 (complex, 8H)

(II) Preparation of composition Each raw material was blended in the blending ratios (parts by weight) of the respective examples and comparative examples shown in the table, mixed uniformly with a mixer, and then vacuum degassed to obtain a composition. About the obtained composition, after observing the property in 50 degreeC, a composition is used for a glass plate (120mmx120mmx5mmt), a polyimide film (Kapton 200H: Toray DuPont Co., Ltd.), a fluororubber O-ring (S- 100: manufactured by Mori Seika Co., Ltd.) and cured by heating in an oven at 150 ° C. for 3 hours. After cooling, the polyimide film was removed by polishing to obtain a cured product.

(III) Evaluation of composition (1) Property: About the composition before hardening prepared by the said method, the presence or absence of insoluble matter and progress of hardening were visually confirmed at 50 degreeC. A uniform clear liquid is desirable.
(2) Curability: Infrared absorption of the cured product by ATR method using a Fourier transform infrared spectroscopic analyzer (Thermo Scientific, FT-IR Nicolet 6700) for the cured product obtained by the above method. The spectrum was measured. Regarding the remaining absorption at 920 cm ⁻¹ and 2250 cm ⁻¹ , neither was observed (◯), either was observed (Δ), and both were observed (×). Absorption at each wave number corresponds to a glycidyl group and a cyanato group, respectively, and it is desirable that the corresponding absorption cannot be confirmed.
(3) Glass transition temperature (Tg): For the cured product that has been cured by the above-described evaluation, in accordance with JIS-K7121, a differential scanning calorimeter (manufactured by Shimadzu Corporation, DSC-50) is used under a nitrogen stream. The temperature was raised to 200 ° C. at a rate of temperature increase of 10 ° C./min, held at 200 ° C. for 10 minutes after the temperature was raised, cooled, and subjected to differential scanning calorimetry when reheated at a rate of temperature increase of 10 ° C./min. The intermediate point glass transition temperature at that time was defined as the glass transition temperature. It can be said that the higher the glass transition temperature, the better the heat resistance.

Claims (13)

(A) 100 parts by weight of a cyanate ester represented by the following formula (1), which is an amorphous liquid at 50 ° C., (B) 20 to 250 parts by weight of an epoxy resin, (C) a metal complex catalyst, and (D) A curable resin composition which is liquid at 50 ° C. and comprises an amine compound having a pKa of a conjugate acid of 5.0 to 12.0 and having no active hydrogen on a nitrogen atom.

In the formula, R1 and R2 are different groups, R1 represents hydrogen or an alkyl group having 1 to 4 carbon atoms, and R2 represents an alkyl group having 1 to 4 carbon atoms.   (A) The cyanate ester is 1,1-bis (4-cyanatophenyl) ethane, 2,2-bis (4-cyanatophenyl) butane, 1,1-bis (4-cyanatophenyl) isobutane and 2 The curable resin composition according to claim 1, which is one or more selected from the group consisting of 1,2-bis (4-cyanatophenyl) -4-methylpentane.   (D) The curable resin composition of Claim 1 or 2 whose amine compound has a tertiary amino group and whose boiling point in a normal pressure is 120 degreeC or more.   (D) The curable resin composition according to claim 1, wherein the amine compound has a pyridine skeleton or a quinoline skeleton, and has a boiling point of 120 ° C. or higher at normal pressure.   (D) The curable resin composition according to claim 1 or 2, wherein the amine compound is one or more selected from the group consisting of 2-dimethylaminoethanol, 4-dimethylaminopyridine and 2,6-lutidine.   (B) The curable resin composition according to any one of claims 1 to 5, wherein the epoxy resin is liquid at 50 ° C.   (B) The epoxy resin is one or more selected from the group consisting of a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a phenol novolac type epoxy resin, and a dihydroxynaphthalene type epoxy resin. The curable resin composition described in 1.   (C) The curable resin composition according to any one of claims 1 to 7, wherein the metal complex catalyst is a metal carboxylate or a metal acetylacetonate complex.   (C) Curable resin composition in any one of Claims 1-8 whose metal complex catalyst is 0.01-0.1 weight part with respect to 100 weight part of (A) cyanate ester resin. (D) An amine compound is 0.05-1.0 weight part with respect to 100 weight part of (B) epoxy resins, The curable resin composition in any one of Claims 1-9. Hardened | cured material formed by hardening the curable resin composition as described in any one of Claims 1-10. The hardened | cured material of Claim 11 formed by thermosetting at the temperature of 180 degrees C or less. The hardened | cured material of Claim 11 formed by thermosetting at the temperature of 160 degrees C or less.

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