Two-component curable resin composition and cured product thereof

Abstract

The purpose of the present invention is to provide a two-component curable resin composition which can maintain flexibility at low temperatures, does not become too soft even at high temperatures, and can obtain a cured product having excellent creep resistance. A two-component curable resin composition containing the following components (A)-(D), the amount of component (C) being 27-80 parts by mass per 100 parts by mass of component (A). Component (A): an epoxy resin, component (B): a metal catalyst, component (C): an organic polymer having a hydrolyzable silyl group, and component (D): a curing agent for an epoxy resin.

Description

Technical Field

[0001] This invention relates to a two-component curable resin composition that maintains flexibility at low temperatures and exhibits excellent creep resistance at high temperatures. Background Technology

[0002] In recent years, the demand for motors used to drive the wheels of electric and hybrid vehicles has been expanding. In motors, adhesives are mostly used to fix magnets, such as for bonding the stator and magnets, and the rotor and magnets. Japanese Patent Application Publication No. 8-283687 discloses that heat-curing epoxy resin is suitable as an adhesive for motors due to its high bonding strength. Furthermore, in recent years, there has been a desire for miniaturization and high output power in motors, leading to the use of neodymium magnets. However, due to the characteristic of neodymium magnets expanding at low temperatures and contracting at high temperatures, epoxy resin is not flexible enough to withstand low or high temperatures caused by changes in external temperature and motor drive, resulting in problems such as the neodymium magnets peeling off due to insufficient adhesion.

[0003] Therefore, methods for incorporating modified silicone resins are known to impart flexibility to epoxy resins. As such a technology, Japanese Patent Application Publication No. 2019-183090 discloses a two-component curable resin composition comprising epoxy resin, a metal catalyst, a modified silicone polymer, and an epoxy resin curing agent. Summary of the Invention

[0004] However, for such a disclosed two-component curable resin composition, due to the characteristics of the modified silicone resin, although it has good flexibility at low temperatures, there is a problem that the resin becomes too soft at high temperatures and its creep resistance deteriorates.

[0005] The present invention was made in view of the above-mentioned situation, and its object is to provide a two-component curable resin composition that can maintain flexibility at low temperatures and has excellent creep resistance at high temperatures.

[0006] The main idea of ​​the present invention will now be described. The embodiments of the present invention overcome the aforementioned problems of the prior art.

[0007] [1] A two-component curable resin composition comprising the following components (A) to (D), wherein component (C) comprises 27 to 80 parts by weight relative to 100 parts by weight of component (A). (A) Components: Epoxy resin, (B) Components: Metal catalyst, (C) Ingredients: Organic polymers containing hydrolyzable silanes. (D) Component: Curing agent for epoxy resin.

[0008] [2] The two-component curable resin composition according to [1] comprises Agent A and Agent B, Agent A being a composition containing component (A) and component (B), and Agent B being a composition containing component (C) and component (D).

[0009] [3] The two-component curable resin composition according to [1] or [2], wherein the above-mentioned component (A) comprises (a1) a bisphenol type epoxy resin and / or (a2) a hydrogenated bisphenol type epoxy resin.

[0010] [4] The two-component curable resin composition according to any one of [1] to [3], wherein the above-mentioned component (B) is a chelate-based titanium catalyst.

[0011] [5] A two-component curable resin composition according to any one of [1] to [4], wherein the above-mentioned component (C) comprises (c1) an organic polymer containing dimethoxysilyl and / or (c2) an organic polymer containing trimethoxysilyl.

[0012] [6] A two-component curable resin composition according to any one of [1] to [5] is used for bonding motor magnets.

[0013] [7] A cured product obtained by curing any two-component curable resin composition described in any one of [1] to [6].

[0014] [8] An electric motor that uses any one of the two-component curable resin compositions described in any one of [1] to [7]. Detailed Implementation

[0015] The present invention will now be described in detail. It should be noted that in this specification, "X to Y" is used to mean "above X and below Y" as a lower and upper limit value, encompassing the numerical values ​​(X and Y) described before and after it. Furthermore, in this specification, the term "(meth)acrylic acid" refers to acrylic acid and / or methacrylic acid.

[0016] This invention relates to a two-component curable resin composition containing components (A) to (D) below, wherein component (C) comprises 27 to 80 parts by weight relative to 100 parts by weight of component (A). (A) Components: Epoxy resin, (B) Components: Metal catalyst, (C) Ingredients: Organic polymers containing hydrolyzable silanes. (D) Component: Curing agent for epoxy resin.

[0017] The two-component curable resin composition of the present invention, having such a configuration, can maintain flexibility at low temperatures and exhibit excellent creep resistance at high temperatures.

[0018] [(A) Ingredient]

[0019] As component (A) of the present invention, it is an epoxy resin. As component (A), any compound having one or more epoxy groups can be solid or liquid, without particular limitation. From the viewpoint of excellent curability at room temperature and creep resistance at high temperature, it is preferable to include an epoxy resin having two or more epoxy groups. The epoxy groups in the epoxy resin are preferably 6, 4, or 3 or less. Furthermore, from the viewpoint of the operability of the two-component curable resin composition, it is preferable to be in a liquid state at 25°C. Specific examples of component (A) include, for instance, bisphenol-type epoxy resins, hydrogenated epoxy resins obtained by hydrogenating epoxy resins having aromatic rings, 1,2-butanediol diglycidyl ether, 1,3-butanediol diglycidyl ether, 1,4-butanediol diglycidyl ether, (poly)ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 2,3-butanediol diglycidyl ether, 1,5-pentanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopentanediol diglycidyl ether, etc. Alkylene glycol-type epoxy resins such as oil ether and 1,4-cyclohexanediethanol diglycidyl ether; phenolic varnish-type epoxy resins such as phenolic varnish-type epoxy resins and cresol varnish-type epoxy resins; glycidylamine compounds such as N,N-diglycidyl-4-glycidoxyaniline, 4,4'-methylenebis(N,N-diglycidylaniline), tetraglycidyldiaminodiphenylmethane, and tetraglycidylm-phenylenediamine; and naphthalene-type epoxy resins having four glycidyl groups. These can be used alone or in combination of two or more. From the perspective of excellent creep resistance at high temperatures, component (A) preferably includes (a1) bisphenol-type epoxy resin and / or (a2) hydrogenated epoxy resin, more preferably includes (a1) bisphenol-type epoxy resin and (a2) hydrogenated epoxy resin, and most preferably includes only (a1) bisphenol-type epoxy resin and (a2) hydrogenated epoxy resin. It should be noted that the silane coupling agent described later is not treated as component (A), but rather as an arbitrary component.

[0020] The aforementioned bisphenol-type epoxy resins are not particularly limited to any epoxy resin with a bisphenol backbone. Examples include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type, bisphenol AD ​​type epoxy resin, urethane-modified bisphenol type epoxy resin, rubber-modified bisphenol type epoxy resin, and polyoxyethylene-modified bisphenol type epoxy resin. They can be used alone or in combination of two or more. From the perspective of superior creep resistance at high temperatures, bisphenol A type epoxy resin and / or bisphenol F type epoxy resin are preferred.

[0021] Commercially available bisphenol-type epoxy resins are not specifically limited in type. Examples include JER828, 834, 1000, 1001, 806, 807 (manufactured by Mitsubishi Chemical Corporation), EPICLON830, 850, 830LVP, 850CRP, 835LV, 860, 1050 (manufactured by DIC Corporation), ADEKA RESIN EP4100, EP4400, EP4901, EP4000, EP4000S (manufactured by ADEKA Corporation), DER-331, 332, 334 (manufactured by The Dow Chemical Company), YD-115, YD-127, YDF-170, YDF-2001 (manufactured by NIPPON STEEL Chemical & Material Co., Ltd.). These can be used individually or in combination of two or more.

[0022] There are no particular limitations on the hydrogenated epoxy resins mentioned above. Examples include hydrogenated bisphenol A type epoxy resin, hydrogenated bisphenol F type epoxy resin, hydrogenated bisphenol E type epoxy resin, and other hydrogenated bisphenol type epoxy resins; hydrogenated cresol phenolic varnish type epoxy resin; hydrogenated phenol phenolic varnish type epoxy resin, etc. Among these, hydrogenated bisphenol type epoxy resins are preferred from the perspective of excellent creep resistance at high temperatures. They can be used individually or in combination.

[0023] Commercially available hydrogenated epoxy resins include, but are not limited to, YX8000, YX8034 (manufactured by Mitsubishi Chemical Corporation), RIKARESIN HBE-100 (manufactured by Shin Nippon Rikka Co., Ltd.), EP-4080E (manufactured by ADEKA Corporation), ST-3000 (manufactured by NIPPON STEEL Chemical & Material Co., Ltd.), and DENACOLEX-252 (manufactured by Nagase ChemteX Corporation). These can be used individually or in combination.

[0024] Preferably, the above-mentioned bisphenol-type epoxy resin and hydrogenated epoxy resin are used in combination. The mass ratio of bisphenol-type epoxy resin to hydrogenated epoxy resin is not particularly limited, but is, for example, in the range of 20:80 to 80:20, preferably in the range of 30:70 to 70:30, and more preferably in the range of 40:60 to 60:40. By using the above ranges, a cured product with superior creep resistance at high temperatures can be obtained.

[0025] [(B) Component]

[0026] The component (B) used in this invention is a metal catalyst. There are no particular limitations on component (B) as long as it is a component that cures component (C) described later. Specific examples of component (B) include tin catalysts such as dibutyltin dilaurate, dibutyltin dioxide, dibutyltin diacetate, dibutyltin distearate, dibutyltin dilaurate oxide, dibutyltin diacetylacetone, dibutyltin dioleoyl maleate, dibutyltin octanoate, dioctyltin dioxide, dioctyltin dilaurate, and reactants of dioctyltin salts with silicates; titanium catalysts such as tetraisopropoxide titanium, diisopropyl di(acetylacetone)titanate, diisopropyl di(acetoacetate)titanate, tetratert-butyl titanate, and tetra-n-butoxytitanium; bismuth catalysts such as bismuth carboxylate, bismuth neodecanoate, bismuth subcarbonate, bismuth benzoate, bismuth rosinate, bismuth neorosinate, and bismuth octanoate; aluminum catalysts; zirconium catalysts; and zinc catalysts. From an environmental perspective, titanium catalysts (other than tin catalysts), bismuth catalysts, aluminum catalysts, zirconium catalysts, and zinc catalysts are preferred. From the perspective of obtaining cured products with excellent curability and low-temperature flexibility, titanium catalysts are most preferred, and chelate-based titanium catalysts such as di(acetylacetonyl)titanate and di(ethyl acetoacetate)titanate are more preferred. They can be used alone or in combination of two or more.

[0027] Commercially available products for component (B) above are not particularly limited. Examples of tin catalysts include NEOSTANNU-100, U-130, U-200, and U-303 (manufactured by Nitto Kasei Corporation). Examples of titanium catalysts include TA-8, TA-10, TA-21, TA-23, TA-30, TA-80, TC-100, TC-120, and TC-401 (manufactured by Matsumoto Fine Chemical Co., Ltd.). Examples of bismuth catalysts include K-KAT348, XK-628, and XK-640 (manufactured by King Industries, Inc.), PUCAT B7, 25, bismuth neodecanoate (manufactured by Nippon Kagaku Sangyo Co., Ltd.), Borchi Kat315, Kat320, and Kat24 (manufactured by Borchers Corporation). Examples of zirconium catalysts include ZA-45 (manufactured by Matsumoto Fine Chemical Co., Ltd.). Examples of aluminum catalysts include DX-9740 (Shin-Etsu Chemical Industry Co., Ltd.), AMD, ASBD, AIPD, ALCH, ALCH-TR, Alumichelate M, Alumichelate D, and Alumichelate A (manufactured by Kawaken FineChemicals Co., Ltd.). Examples of zinc catalysts include K-KAT 670 (manufactured by King Industries, Inc.).

[0028] The amount of component (B) added is 0.1 to 50 parts by mass relative to 100 parts by mass of component (C) described later, more preferably 0.5 to 30 parts by mass, particularly preferably 1 to 15 parts by mass, most preferably 3 to 15 parts by mass, and even more preferably in the range of 5 to 10 parts by mass. By adding 0.1 parts by mass or more, excellent curing properties at room temperature are obtained; by adding 50 parts by mass or less, a cured product with excellent flexibility at low temperatures can be obtained. It should be noted that when two or more components (B) are used, the above content refers to their total amount.

[0029] [(C) Component]

[0030] The component (C) used in this invention is an organic polymer containing hydrolyzable silanes. There are no particular limitations on component (C) as long as it is an organic polymer containing hydrolyzable silanes in its molecule. From the perspective of balancing flexibility at low temperatures and creep resistance at high temperatures, organic polymers containing two or more hydrolyzable silanes are preferred, and those containing hydrolyzable silanes at the terminal are even more preferred. Examples of hydrolyzable silanes include alkoxysilanes, such as dimethoxysilane, trimethoxysilane, diethoxysilane, and triethoxysilane. From the perspective of excellent curability, dimethoxysilane and / or trimethoxysilane are preferred. These components can be used individually or in combination of two or more. From the perspective of excellent curability, component (C) preferably includes (c1) an organic polymer having a dimethoxysilyl group and / or (c2) an organic polymer having a trimethoxysilyl group. From the perspective of improving creep resistance at high temperatures, it is more preferable to include (c1) an organic polymer having a dimethoxysilyl group and (c2) an organic polymer having a trimethoxysilyl group. Furthermore, from a disposal perspective, component (C) is preferably liquid at 25°C. It should be noted that the silane coupling agent and preservation stabilizer described later are not treated as component (C), but are treated as optional components. It should be noted that when (c1) and (c2) are used together, the mass ratio of (c1) to (c2) is preferably 30:70 to 70:30, and more preferably 40:60 to 60:40.

[0031] The structure of the organic polymer in component (C) above is not particularly limited, and examples include structures such as polyoxyethylene, polyester, polycarbonate, polyurethane, polyamide, polyurea, polyimide, polyethylene, polypropylene, polyisobutylene, (meth)acrylic polymers, polystyrene, polyvinyl chloride, polybutadiene, polyisoprene, polyvinyl butyral, and polyvinyl ether. From the perspective of balancing flexibility at low temperatures and creep resistance at high temperatures, the organic polymer in component (C) preferably contains a polyoxyethylene structure. That is, component (C) preferably contains a polyoxyethylene polymer containing hydrolyzable silane groups. These can be used alone or in combination of two or more.

[0032] Commercially available examples of polyoxyethylene polymers containing hydrolyzable silyl groups as component (C) above include SAT010, SAX115, SAT030, SAT030, SAT200, SAT350, SAT400, SAX220, SAX510, SAX530, SAX575, SAX580, SAX710, SAX720, SAX725, SAX750, SAX770, S203, S303, S203H, S303H, S943S, S911S, MA440, MA447, MA451, MA903, MA903M, MA904, S943, MAX923, MAX951, SAX510, SAX520, SAX530, SAX580, etc. (Kaneka) Corporation), ES-S2410, ES-S2420, ES-S3430, ES-S3610, ES-S3630 (manufactured by Asahi Glass Co., Ltd.).

[0033] As for the amount of component (C) added, relative to 100 parts by mass of component (A), component (C) is 27 to 80 parts by mass, more preferably 30 to 75 parts by mass. By adding 27 parts by mass or more, excellent flexibility at low temperatures is achieved; by adding 80 parts by mass or less, a cured product with excellent creep resistance at high temperatures can be obtained. It should be noted that when two or more components (C) are used, the above content refers to their total amount.

[0034] [(D) component]

[0035] As component (D) of the present invention, the curing agent for epoxy resin is not particularly limited, as long as it is a compound capable of curing component (A). Examples of components (D) include amine compounds, polythiol compounds, and acid anhydride compounds, with amine compounds being preferred from the viewpoint of excellent room temperature curing properties. From the viewpoint of curing properties and workability after mixing, the above-mentioned component (D) is preferably in a liquid state at 25°C. They can be used alone or in combination of two or more. It should be noted that the silane coupling agent described later is not treated as component (D), but is treated as an arbitrary component.

[0036] Examples of the aforementioned amine compounds include primary amines, secondary amines, tertiary amines, amine adducts, polyamide compounds, and imidazole compounds. From the viewpoint of excellent curability at room temperature and creep resistance at high temperatures, primary amines, secondary amines, and tertiary amines are preferred, secondary amines and tertiary amines are further preferred, and tertiary amines are most preferred. They can be used alone or in combination of two or more.

[0037] Examples of primary amines include aliphatic primary amines, alicyclic primary amines, and aromatic primary amines. Among the aforementioned aliphatic primary amines, there are no particular limitations; examples include ethylenediamine, diethylenetriamine, triethylenetetramine, and hexamethylenediamine. Furthermore, examples of the aforementioned alicyclic primary amines include menthol diamine, isophorone diamine, N-aminoethylpiperazine, diaminodicyclohexylmethane, and norbornene diamine. Furthermore, examples of aromatic primary amines include dimethylaminomethylphenol, m-phenylenediamine, m-phenylenediamine, diaminodiphenylmethane, diaminodiphenyl sulfone, and diaminodiethyldiphenylmethane.

[0038] There are no particular limitations on the secondary or tertiary amines mentioned above, and examples include piperidine, pyridine, benzyldimethylamine, 2-(dimethylaminomethyl)phenol, triethylenediamine, dimethylcyclohexylamine, dimethylbenzylamine, dimethylhexylamine, dimethylaminophenol, dimethylaminop-cresol, piperidine, 1,4-diazabicyclo[2.2.2]octane, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo[5.4.0]undecene-1. From the viewpoint of excellent curability at room temperature and creep resistance at high temperatures, compounds having aromatic rings are preferred as secondary or tertiary amines, and 2,4,6-tris(dimethylaminomethyl)phenol is even more preferred. Commercially available products include, for example, K-54 (Air Products Japan KK).

[0039] There are no particular limitations on the imidazoles mentioned above, and examples include 2-methylimidazole, 1,2-dimethylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1-isobutyl-2-methylimidazole, 2-phenyl-4-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 2,4-diamino-6(2'-methylimidazole (1')) ethyltriazine, 2,4-diamino-6(2'-undecylimidazole (1')) ethyltriazine, 2,4-diamino-6(2'-ethyl, 4-Methylimidazole (1') ethyltriazine, 2-phenyl-3,5-dihydroxymethylimidazole, 2-phenyl-4-hydroxymethyl-5-methylimidazole, 1-cyanoethyl-2-phenyl-3,5-dicyanoethoxymethylimidazole, etc.

[0040] Examples of the aforementioned amine adduct compounds include compounds that cause the addition of tertiary amines or imidazole compounds to epoxy resins, thereby halting the reaction midway. Considering storage stability and curability, fine powders obtained by pulverizing the aforementioned epoxy adduct compounds are most preferred. Commercially available epoxy adduct compounds include the Amicure series manufactured by Ajinomoto Fine-TechnoCo., Inc., the Fujicure series manufactured by T&K TOKA Corporation, and the Novacure series manufactured by Asahi KaseiCorp.

[0041] There are no particular limitations on the polythiol compounds mentioned above, and examples include 3,3'-dithiodipropionic acid, trimethylolpropane tris(thioglycolate), pentaerythritol tetra(thioglycolate), ethylene glycol dithioglycolate, 1,4-bis(3-mercaptobutyryloxy)butane, tris[(3-mercaptopropionyloxy)-ethyl]-isocyanurate (TEMPIC), and 1,3,5-tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine- Alkyl polythiols such as 2,4,6(1H,3H,5H)-trione, trimethylolpropane tris(3-mercaptopropionate) (TMMP), pentaerythritol tetra(3-mercaptopropionate) (PEMP), pentaerythritol tetra(3-mercaptobutyrate), dipentaerythritol hexa(3-mercaptopropionate) (DPMP), 1,4-butanedithiol, 1,6-hexanedithiol, and 1,10-decanedithiol; polysulfides containing terminal thiol groups, etc.

[0042] There are no particular limitations on the aforementioned acid anhydride compounds, and examples include tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylneodymethylenetetrahydrophthalic anhydride, trialkyltetrahydrophthalic anhydride, methylnadic anhydride, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and maleic anhydride.

[0043] The amount of component (D) added relative to 100 parts by weight of component (A) is 0.1 to 50 parts by weight, more preferably 1 to 20 parts by weight, more preferably 1 to 10 parts by weight, and most preferably 1 to 5 parts by weight. When the amount is 0.1 parts by weight or more, excellent curing properties at room temperature are obtained; when the amount is 50 parts by weight or less, a cured product with excellent flexibility at low temperatures can be obtained. It should be noted that when two or more components (D) are used, the above content refers to their total amount.

[0044] For the purposes of this invention, as any component, additives such as curing accelerators, fillers, various elastomers such as styrene copolymers, reactive diluents, silane coupling agents, preservation stabilizers, antioxidants, light stabilizers, heavy metal passivators, plasticizers, defoamers, pigments, dyes, solvents, rust inhibitors, leveling agents, dispersants, rheology modifiers, flame retardants, and surfactants may be used without prejudice to the purpose of this invention.

[0045] In order to improve the flexibility at low temperatures and the creep resistance at high temperatures, filler materials can be added to this invention. Specifically, examples include organic powders, inorganic powders, and metallic powders. Examples of inorganic powder filler materials include glass, talc, fumed silica, mica, ceramics, silicone rubber powder, calcium carbonate, carbon powder, kaolin, dried clay minerals, and dried diatomaceous earth. Examples of organic powder filler materials include polyethylene, polypropylene, nylon, cross-linked acrylics, cross-linked polystyrene, polyester, polyvinyl alcohol, polyvinyl butyral, and polycarbonate. Examples of metallic powder filler materials include gold, silver, copper, alumina, aluminum nitride, and aluminum hydroxide. The amount of filler material added is not particularly limited, but is preferably 0.1 to 90% by mass, more preferably 0.5 to 85% by mass, and most preferably 1 to 80% by mass, relative to the total amount of the two-component curable resin composition. By using a concentration of 0.1% or more by mass, excellent creep resistance at high temperatures can be obtained; by using a concentration of 90% or less by mass, a cured product with excellent flexibility at low temperatures can be obtained.

[0046] The aforementioned fumed silica is formulated to adjust the viscosity of the two-component curable resin composition or to improve the resin strength of the cured product. Preferably, fumed silica that has undergone surface treatment with dimethylsilane, trimethylsilane, alkylsilane, methacryloxysilane, organochlorosilane, polydimethylsiloxane, hexamethyldisilazane, etc., is used. Commercially available fumed silica products include, for example, AEROSIL R972, R972V, R972CF, R974, R976, R976S, R9200, RX50, NAX50, NX90, RX200, RX300, R812, R812S, R8200, RY50, NY50, RY200S, RY200, RY300, R104, R106, R202, R805, R816, T805, R711, RM50, R7200 (manufactured by Nippon Aerosil Co., Ltd.), and TS720 (Cabot Corporation).

[0047] Examples of the aforementioned preservation stabilizers include tetramethoxysilanes, tetraethoxysilanes, and other tetrafunctional alkoxysilanes; methyltrimethoxysilanes, methyltriethoxysilanes; ethyl silicate, propyl silicate, and butyl silicate, representing silicate compounds. These can be used alone or in combination of two or more. The preservation stabilizers are not treated as components (C) above or as silane coupling agents described later.

[0048] Examples of silane coupling agents that can be used in this invention include, for example, silane coupling agents containing glycidyl groups such as 3-glycidylpropoxypropyltriethoxysilane, 3-glycidylpropoxypropylmethyldimethoxysilane, 3-glycidylpropoxypropyltrimethoxysilane, and 3-glycidylpropoxypropylmethyldiethoxysilane; silane coupling agents containing vinyl groups such as vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, and vinyltrimethoxysilane; and silane coupling agents containing (β-methoxyethoxy) groups such as 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, and 3-methacryloyloxypropyltrimethoxysilane. The preferred silane coupling agents are those containing amino groups, such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, and their oligomers. Considering excellent creep resistance at high temperatures, silane coupling agents containing glycidyl groups and silane coupling agents containing amino groups are preferred. Further preferred are silane coupling agents containing glycidyl groups and silane coupling agents containing amino groups used in combination. Most preferred are 3-glycidoxypropyltrimethoxysilane and 3-(2-aminoethyl)aminopropyltrimethoxysilane used in combination. These can be used alone or in combination of two or more. From the perspective of further improving creep resistance at high temperatures, it is more preferable to use a silane coupling agent containing glycidyl groups and a silane coupling agent containing amino groups. Furthermore, as a two-component curable resin composition, from the viewpoint of excellent preservation, it is preferable to contain a silane coupling agent containing glycidyl groups in a liquid different from component (D) above, and it is preferable to contain a silane coupling agent containing amino groups in a liquid different from component (A) above. In addition, the aforementioned silane coupling agents are not treated as components (A) to (D). Furthermore, the silane compounds contained in the preservation stabilizer are not treated as silane coupling agents.

[0049] There are no particular limitations on commercially available silane coupling agents. Examples include KBM-1003, KBE-1003, KBM-303, KBM-403, KBE-403, KBM-502, KBE-502, KBM-503, KBE-503, KBM-5103, KBM-1403, KBM-602, KBM-603, KBM-903, KBE-903 (manufactured by Shin-Etsu Chemical Industry Co., Ltd.), Z-6610, Z-6044, Z-6825, Z-6033, Z-6062, and Z-6094 (manufactured by Toray-Dow Corning Co., Ltd.).

[0050] The content of the silane coupling agent, relative to the combined amount of components (A) and (C) of 100 parts by mass, is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, and most preferably 0.5 to 5 parts by mass. A content of 0.1 parts by mass or more results in excellent creep resistance at high temperatures, while a content of 20 parts by mass or less yields a cured product with excellent flexibility at low temperatures. It should be noted that when two or more silane coupling agents are used, the above content refers to their combined amount.

[0051] Examples of plasticizers that can be used in this invention include, for example, aromatic polycarboxylate plasticizers; dioctyl phthalate (DOP), dibutyl phthalate (DBP), diheptyl phthalate (DHP), diisononyl phthalate (DINP), diisodecyl phthalate (DIDP), and butyl benzyl phthalate (BBP) plasticizers; trioctyl trimellitate (TOTM) and triisodecyl trimellitate (TITM) plasticizers; tetraoctyl pyromellitic ester plasticizers; and di-2-ethylhexyl adipate (DOA) and isodecanyl adipate plasticizers. Examples of phosphate ester plasticizers include DIDA, di-2-ethylhexyl sebacate (DOS), dibutyl sebacate (DBS), di-2-ethylhexyl maleate (DOM), dibutyl fumarate (DBF), di-2-ethylhexyl azelate (DOZ), di-2-ethylhexyl phthalate, trioctyl citrate, and glyceryl triacetate. Examples of phosphate ester plasticizers include trimethyl phosphate, tributyl phosphate, tri(2-ethylhexyl) phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, alkylaryl phosphate, triethyl phosphate, tri(chloroethyl) phosphate, tri(dichloropropyl) phosphate, tri(β-chloropropyl) phosphate, octyl diphenyl phosphate, tri(isopropylphenyl) phosphate, and toluene phenyl phosphate, but these are not limited to these. They can be used alone or in combination of two or more.

[0052] The two-component curable resin composition of the present invention preferably consists of agent A and agent B, where agent A is a composition containing components (A) and (B), and agent B is a composition containing components (C) and (D). By separating the components into different liquids as described above, unwanted reactions during storage can be suppressed, thereby improving storage stability. Any component such as the silane coupling agent and filler can be included in either agent A or agent B, but from the perspective of improving adhesion to the base agent and excellent creep resistance, the silane coupling agent is preferably included in agent A and agent B at a mass ratio of 10:90 to 90:10, more preferably 20:80 to 80:20, and most preferably 20:80 to 60:40. The amount of filler contained in agent A can be more or less than the amount of filler contained in agent B, or it can be the same as the amount of filler contained in agent B. The filler material is preferably contained in agent A and agent B in a mass ratio of 5:95 to 95:5, more preferably 10:90 to 90:10, and most preferably 20:80 to 80:20. The two-component curable resin composition is used by mixing the two liquids. It should be noted that the mixing ratio of agent A to agent B, by mass ratio, is in the range of 95:5 to 5:95, more preferably 90:10 to 10:90, particularly preferably in the range of 80:20 to 20:80, and most preferably 80:20 to 50:50. By using the above ranges, a cured product with excellent creep resistance at high temperatures and flexibility at low temperatures can be obtained.

[0053] The cured product obtained by curing the two-component curable resin composition of the present invention is also an aspect of the invention. As a curing method, it is preferable to mix the two liquids separately at a predetermined ratio and then allow them to stand at 25°C for 12 to 240 hours, more preferably 72 to 240 hours, and most preferably 120 to 192 hours. Alternatively, the two-component curable resin composition can also be cured by heating. In the case of heating curing, the curing temperature is preferably 50 to 150°C, more preferably 60 to 120°C, and most preferably 70 to 100°C. Furthermore, the relative humidity is preferably 40%RH or higher, and the curing time is preferably 0.5 to 10 hours, more preferably 1 to 8 hours, and most preferably 3 to 6 hours.

[0054] The two-component curable resin composition of the present invention is preferably used in various applications such as adhesives, sealants, potting compounds, coatings, lining materials, heat dissipation materials, conductive pastes, and structural bonding. Among these applications, it is particularly preferred for bonding motor magnets, considering both creep resistance at high temperatures and flexibility at low temperatures. Furthermore, a motor bonded using the two-component curable resin composition of the present invention is also a manifestation of the present invention.

[0055] The two-component curable resin composition of the present invention is suitable as an adhesive. There are no particular limitations on the adherends; examples include metals to each other, metals to magnets, metals to plastics, metals to rubber, metals to glass, plastics to rubber, plastics to glass, plastics to each other, rubbers to each other, rubbers to glass, and glass to each other. Among these, metals to each other, metals to magnets, and metals to plastics are preferred, and from the perspective of excellent adhesion to motor magnets, the application of metals to magnets is preferred.

[0056] There are no particular limitations on the metals mentioned above; examples include gold, silver, iron, aluminum, magnesium, copper, steel, stainless steel, and titanium. As for magnets, examples include ferrite magnets, alloy magnets, and neodymium magnets. Neodymium magnets are suitable for bonding due to their ability to balance creep resistance at high temperatures and flexibility at low temperatures. Regarding plastics, there are no particular limitations; examples include fiber-reinforced plastics (FRP), carbon fiber-reinforced plastics (CFRP), polyacrylic acid, polyester, polyamide, acrylonitrile-butadiene-styrene, 6-nylon, polycarbonate, polyacetal, polyethylene terephthalate, polybutylene terephthalate, polyphenylene sulfide, polyphenylene ether, polyetheretherketone, polyethylene, and polypropylene. Regarding rubbers, there are no particular limitations; examples include nitrile rubber, butyl rubber, polyurethane rubber, silicone rubber, and EPDM. Bonding of at least two or more of these materials to each other is an example. Alternatively, the surface of the aforementioned materials can be pre-treated, or left untreated.

[0057] Example

[0058] The present invention will be described in more detail below with reference to specific embodiments, but the present invention is not limited to these embodiments.

[0059] <Preparation of Two-Component Curable Resin Compositions>

[0060] The test methods used in the examples and comparative examples are described below. The components were collected in parts by mass as shown in Table 1 and mixed at room temperature for 60 minutes using a mixer to prepare Agent A and Agent B, respectively, equivalent to the two-component curable resin composition. It should be noted that the detailed preparation quantities are based on Table 1, and all values ​​are expressed in parts by mass.

[0061] (A) Component: Epoxy resin

[0062] • (a1): Bisphenol A type epoxy resin (epoxy group: 2 functional, liquid at 25°C, manufactured by Mitsubishi Chemical Corporation, jER828)

[0063] • (a2): Hydrogenated bisphenol A type epoxy resin (epoxy group: 2 functional, liquid at 25°C, manufactured by Shin Nippon Rikka Co., Ltd., RIKARESIN HBE-100)

[0064] (B) Components: Metal catalyst

[0065] • Diisopropyl di(acetylacetonyl)titanate (manufactured by Matsumoto Fine Chemical Co., Ltd., TC-100)

[0066] (C) Ingredients: Organic polymers containing hydrolyzable silanes

[0067] • (c1) Polyoxyethylene with dimethoxysilyl groups at both ends (liquid at 25°C, manufactured by Kaneka Corporation, SAX-750)

[0068] • (c2) Polyoxyethylene with trimethoxysilyl groups at both ends (liquid at 25°C, manufactured by Kaneka Corporation, SAX-575)

[0069] (D) Component: Curing agent for epoxy resin

[0070] ·2,4,6-Tris(dimethylaminomethyl)phenol (manufactured by Air Products Japan KK, Ancamine K-54)

[0071] Any component

[0072] ·3-Epoxypropoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403)

[0073] ·3-(2-Aminoethyl)aminopropyltrimethoxysilane (manufactured by Dow Toray Co., Ltd., Z-6094)

[0074] <Dynamic Viscoelasticity Measurement (DMA) (After Curing)>

[0075] In an environment of 25°C and 50% RH, the A and B components of each two-component curable resin composition were mixed for 10 minutes using a wooden stick at a ratio equal to the total amount listed in Table 1. The mixed composition was then formed into sheets with a length of 60 mm, a width of 10 mm, and a thickness of 1.0 mm, and allowed to stand at 25°C for 168 hours to produce cured products. The cured products were then mounted on the tensile mode fixture of a dynamic viscoelasticity measuring apparatus DMS6100 manufactured by Hitachi High-Tech Science Co., Ltd., and measurements were taken at a frequency of 1 Hz in a temperature range of -50°C to 200°C. The "storage modulus of elasticity (Pa)" at -40°C and 160°C was confirmed at a frequency of 1 Hz. From the perspective of excellent flexibility at low temperatures, the "storage modulus of elasticity (-40°C)" is preferably 1.0 × 10⁻⁶. 9 Below Pa. Furthermore, considering excellent creep resistance at high temperatures, the "storage modulus (160℃)" is preferably 2.5 × 10⁻⁶. 7 Pa or higher, more preferably 4.0~6.0×10 Pa. 7 Pa.

[0076] <Preparation of the test piece>

[0077] At 25°C and 50% RH, the A and B components of each two-component curing resin composition were mixed for 10 minutes using a wooden stick at a ratio equal to the total amount described in Table 1. Next, the mixed composition was applied to an SPCC-SD sheet (100 mm long × 25 mm wide × 1.6 mm thick) with an adhesive area of ​​1 mm long × 3.5 mm wide and a resin thickness of 0.08 mm. Another SPCC-SD sheet was then attached and fixed. Test pieces were then prepared by incubating at 25°C for 168 hours.

[0078] <Creep Test>

[0079] A 750g weight was attached to one end of the test piece. Then, the piece was suspended with the opposite end facing upwards and placed in a hot air drying oven set at 160°C. After 800 hours, the test piece was removed from the oven, and visual inspection was performed to confirm whether the bonded areas had peeled off and whether the piece had detached. Then, creep resistance was assessed according to the evaluation criteria.

[0080] Evaluation Criteria

[0081] ○: The test piece did not fall off.

[0082] ×: Test piece detached

[0083] Based on the results of Examples 1-6 in Table 1, it was confirmed that the two-component curable resin compositions of the present invention exhibit excellent flexibility at low temperatures and excellent creep resistance at high temperatures. Specifically, for Examples 1-4 which use two or more of any of components (A) and (C), the storage modulus of elasticity at 160°C is 6.5 × 10⁻⁶. 7 Below Pa is a better result. In contrast, it was confirmed that in Comparative Examples 1 and 2, relative to 100 parts by mass of component (A), component (C) exceeded 80 parts by mass, therefore, the energy storage modulus at high temperature of 160°C was low and the creep resistance was poor. In addition, in Comparative Example 3, relative to 100 parts by mass of component (A), component (C) was less than 27 parts by mass, therefore, it was confirmed that the energy storage modulus at low temperature was high and the flexibility was poor.

[0084] Industrial applicability

[0085] The two-component curable resin composition of the present invention maintains flexibility at low temperatures and exhibits excellent creep resistance at high temperatures. Therefore, it is suitable for various applications such as adhesives, sealants, potting compounds, coatings, conductive pastes, heat dissipation agents, and flame retardants. Consequently, it can be applied in a wide range of fields and is therefore industrially useful.

[0086] This application is based on Japanese Patent Application No. 2023-193440, filed on November 14, 2023, the disclosure of which is referenced and incorporated herein by reference in its entirety.

Claims

1. A two-component curable resin composition comprising components (A) to (D) wherein, relative to 100 parts by weight of component (A), component (C) comprises 27 to 80 parts by weight. (A) Components: Epoxy resin, (B) Components: Metal catalyst, (C) Ingredients: Organic polymers containing hydrolyzable silanes. (D) Component: Curing agent for epoxy resin.

2. The two-component curable resin composition according to claim 1, comprising agent A and agent B, wherein agent A is a composition containing component (A) and component (B), and agent B is a composition containing component (C) and component (D).

3. The two-component curable resin composition according to claim 1, wherein, The component (A) comprises (a1) a bisphenol type epoxy resin and / or (a2) a hydrogenated bisphenol type epoxy resin.

4. The two-component curable resin composition according to claim 1, wherein, The component (B) is a chelate-based titanium catalyst.

5. The two-component curable resin composition according to claim 1, wherein, The (C) component comprises (c1) an organic polymer containing dimethoxysilyl and / or (c2) an organic polymer containing trimethoxysilyl.

6. The two-component curable resin composition according to claim 1, used for bonding motor magnets.

7. A cured product obtained by curing the two-component curable resin composition of claim 1.

8. An electric motor that uses the two-component curable resin composition of claim 1.

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