Curable resin composition

Abstract

The present invention provides a means that is capable of maintaining resistance to a coolant. A moisture-curable resin composition according to the present invention contains the following components (A) to (D): Component (A): an organic polymer having a hydrolyzable silyl group; component (B): an organic zinc catalyst; component (C): (C-1) a monoamine compound having a C7-C20 alkyl group and / or (C-2) a diamine compound which has a nitrogen atom and is such that a C5 or less alkyl group is directly bonded to the nitrogen atom; and component (D): a silane coupling agent having an epoxy group.

Description

Curable resin composition

[0001] The present invention relates to a curable resin composition that is resistant to coolants (antifreeze).

[0002] Coolant (antifreeze) sealants are needed as sealants for the periphery of automotive drive components and on-board components. However, as coolants become more sophisticated, conventional sealants are unable to provide satisfactory sealing properties. JP 2008-274119 A describes a photocurable composition that is resistant to coolants. However, in the case of photocurable compositions, if fillers, coloring powders, etc. are included, the light energy may not reach the interior of the composition, resulting in the interior remaining uncured. Furthermore, JP 2008-274119 A does not describe adhesion to adherends, and peeling from the adherend causes the sealant to lose its function.

[0003] Aluminum components are widely used in automotive drivetrains, on-board components, radiators, etc. Conventional sealants have poor adhesion and sealing properties to metals such as aluminum, making it difficult to maintain resistance to coolants.

[0004] As a result of extensive research into achieving the above object, the present inventors discovered a method for producing a curable resin composition that is resistant to coolants, and thus completed the present invention.

[0005] The gist of the present invention is described below. [1] A moisture-curable resin composition comprising the following components (A) to (D): Component (A): an organic polymer having a hydrolyzable silyl group; Component (B): an organozinc catalyst; Component (C): (C-1) a monoamine compound having an alkyl group of 7 to 20 carbon atoms and / or (C-2) a diamine compound in which an alkyl group having less than 5 carbon atoms is directly bonded to a nitrogen atom; and Component (D): a silane coupling agent having an epoxy group. [2] The moisture-curable resin composition according to [1], wherein the main skeleton of the organic polymer of component (A) is a (meth)acrylic polymer. [3] The moisture-curable resin composition according to [1] or [2], wherein the hydrolyzable silyl group of component (A) is a dialkoxysilyl group. [4] The moisture-curable resin composition according to any one of [1] to [3], wherein component (C) is present in an amount of 0.1 to 20 parts by mass per part by mass of component (B). [5] The moisture-curable resin composition according to any one of [1] to [4], wherein the amount of the (D) component is 0.1 to 11 parts by mass per part by mass of the (C) component. [6] A two-part moisture-curable resin composition comprising a component A containing the following components (A) to (C) and a component B containing the following component (D): Component (A): an organic polymer having a hydrolyzable silyl group; Component (B): an organic zinc catalyst; Component (C): (C-1) a monoamine compound having an alkyl group of 7 to 20 carbon atoms and / or (C-2) a diamine compound having an alkyl group of less than 5 carbon atoms directly bonded to a nitrogen atom; and Component (D): a silane coupling agent having an epoxy group. [7] A cured product obtained by curing the moisture-curable resin composition according to any one of [1] to [6]. [8] The moisture-curable resin composition according to any one of [1] to [6], wherein the adherend is aluminum and / or polyphenylene sulfide.

[0006] One aspect of the present invention is a moisture-curable resin composition comprising the following components (A) to (D): component (A): an organic polymer having a hydrolyzable silyl group; component (B): an organozinc catalyst; component (C): (C-1) a monoamine compound having an alkyl group of 7 to 20 carbon atoms and / or (C-2) a diamine compound in which an alkyl group having less than 5 carbon atoms is directly bonded to a nitrogen atom; and component (D): a silane coupling agent having an epoxy group.

[0007] The moisture-curable resin composition according to the present invention has high adhesiveness and sealing properties to metals such as aluminum, and a cured product of the moisture-curable resin composition according to the present invention can have excellent resistance to coolants.

[0008] The details of the present invention will now be described.

[0009] The component (A) that can be used in the present invention is an organic polymer having one or more hydrolyzable silyl groups per molecule. Considering reactivity, it is preferable for one molecule to have two or more hydrolyzable silyl groups. The hydrolyzable silyl groups can be present either in the side chains of the organic polymer or at the terminals of the main backbone of the organic polymer. From the viewpoint of rubber elasticity and flexibility, it is preferable for the hydrolyzable silyl groups to be present at both terminals of the main backbone of the polymer. The component (A) may be used alone or in combination of two or more. Examples of the main backbone of the component (A) include polyoxyalkylene, polyester, polycarbonate, polyurethane, polyamide, polyurea, polyimide, polyethylene, polypropylene, polyisobutylene, (meth)acrylic polymer, polystyrene, polyvinyl chloride, polybutadiene, polyisoprene, polyvinyl butyral, and polyvinyl ether. From the viewpoint of coolant resistance, the main backbone of the component (A) is preferably a polymer of a (meth)acrylic monomer. That is, the component (A) is preferably an organic polymer having a main skeleton of a (meth)acrylic polymer whose main monomer component is a (meth)acrylic monomer, and having one or more hydrolyzable silyl groups in each molecule.

[0010] A hydrolyzable silyl group is a group that can crosslink by forming a siloxane bond through a condensation reaction, and is a functional group having one to three hydrolyzable groups bonded to a silicon atom. Examples of the hydrolyzable group include an alkoxy group, an alkenyloxy group, an acyloxy group, an amino group, an aminooxy group, an oxime group, and an amide group. Examples of the hydrolyzable silyl group include an alkoxysilyl group, an alkenyloxysilyl group, an acyloxysilyl group, an aminosilyl group, an aminooxysilyl group, an oximesilyl group, and an amidesilyl group. From the viewpoint of ease of handling, the hydrolyzable silyl group is preferably an alkoxysilyl group.

[0011] The alkoxy group bonded to the silicon atom of the alkoxysilyl group is not particularly limited. The alkoxy group is, for example, a linear or branched alkoxy group having 1 to 20 carbon atoms, preferably a linear or branched alkoxy group having 1 to 8 carbon atoms. Examples of the alkoxy group include a methoxy group, an ethoxy group, and a propoxy group. A group other than an alkoxy group may be bonded to the silicon atom of the alkoxysilyl group. Examples of groups other than an alkoxy group include a hydrogen atom, an alkyl group, an alkenyl group, and an arylalkyl group. Among these, the group other than an alkoxy group is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, more preferably a linear or branched alkyl group having 1 to 8 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, or an isopropyl group. Examples of alkoxysilyl groups include alkyldialkoxysilyl groups (dialkoxysilyl groups), trialkoxysilyl groups, trimethoxysilyl groups, triethoxysilyl groups, triisopropoxysilyl groups, methyldimethoxysilyl groups, and methyldiethoxysilyl groups. In consideration of reactivity, the hydrolyzable silyl group of component (A) is preferably an alkyldialkoxysilyl group, and most preferably a methyldimethoxysilyl group.

[0012] The (meth)acrylic monomer constituting the (meth)acrylic polymer as the main skeleton is not particularly limited, and various types can be used. The (meth)acrylic monomer is a monomer having an acrylic group (acryloyl group) (H ２ C=CH-C(=O)-) or methacryl group (methacryloyl group) (H ２ C=C(CH ３)-C(=O)-) is a general term for monomers having the formula: Examples of the (meth)acrylic monomer include (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, phenyl (meth)acrylate, toluyl (meth)acrylate, benzyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, Examples of the (meth)acrylic polymer include, but are not limited to, propyl, stearyl (meth)acrylate, glycidyl (meth)acrylate, 2-aminoethyl (meth)acrylate, γ-(methacryloyloxypropyl)trimethoxysilane, ethylene oxide adduct of (meth)acrylic acid, trifluoromethylmethyl (meth)acrylate, 2-trifluoromethylethyl (meth)acrylate, 2-perfluoroethylethyl (meth)acrylate, 2-perfluoroethyl-2-perfluorobutylethyl (meth)acrylate, 2-perfluoroethyl, perfluoromethyl (meth)acrylate, diperfluoromethylmethyl (meth)acrylate, 2-perfluoromethyl-2-perfluoroethylmethyl (meth)acrylate, 2-perfluorohexylethyl (meth)acrylate, 2-perfluorodecylethyl (meth)acrylate, and 2-perfluorohexadecylethyl (meth)acrylate. The (meth)acrylic polymer according to the present invention can be obtained by polymerizing a selected (meth)acrylic monomer. The (meth)acrylic monomer is preferably a (meth)acrylic monomer having a hydrocarbon group.

[0013] In the (meth)acrylic polymer that is the main skeleton, the constituent units derived from (meth)acrylic monomers are preferably 50 mol % or more, more preferably 70 mol % or more, even more preferably 90 mol % or more, and most preferably 100 mol %.

[0014] The (meth)acrylic polymer as the main skeleton may contain structural units derived from other monomers copolymerizable with the (meth)acrylic monomer. Examples of such other monomers include amide group-containing monomers such as (meth)acrylamide and N-methylol(meth)acrylamide, amino group-containing monomers such as aminoethyl vinyl ether, and monomers such as acrylonitrile, styrene, α-methylstyrene, alkyl vinyl ether, vinyl chloride, vinyl acetate, vinyl propionate, and ethylene.

[0015] The number average molecular weight (Mn) of the organic polymer of component (A) is preferably 500 or more, more preferably 3,000 or more. The number average molecular weight (Mn) of the organic polymer of component (A) is preferably 100,000 or less, more preferably 50,000 or less. When the number average molecular weight of the organic polymer is 500 or more, the elasticity of the cured product of the moisture-curable resin composition of the present invention is easily expressed. When the number average molecular weight of the organic polymer is 100,000 or less, the viscosity of the moisture-curable resin composition of the present invention can be adjusted appropriately, and stringiness when the moisture-curable resin composition of the present invention is suppressed when it is applied. The number average molecular weight of the organic polymer of component (A) can be measured by gel permeation chromatography (GPC) using polystyrene as a standard substance. The viscosity of the organic polymer of component (A) affects the viscosity of the moisture-curable resin composition of the present invention, so considering the coatability, it is preferably 100 to 1,000 Pa·s at 23 to 25°C.

[0016] The organic polymer of component (A) can be obtained by various polymerization methods, and the method is not particularly limited. The polymerization method is preferably a radical polymerization method in terms of the versatility of the monomer and ease of reaction control. The radical polymerization is preferably controlled radical polymerization, more preferably living radical polymerization, and particularly preferably atom transfer radical polymerization. The method of introducing a hydrolyzable silyl group into the (meth)acrylic polymer main skeleton is a known method, and is described in JP-A-09-272714 (U.S. Pat. No. 5,986,014), JP-A-11-043512, etc.

[0017] Specific examples (commercially available products) of component (A) include, but are not limited to, KANEKA XMAP (registered trademark) series SA110S, SA100S, SA120S, and OR110S manufactured by Kaneka Corporation.

[0018] The component (B) that can be used in the present invention is an organozinc catalyst. The component (B) can cause a condensation reaction of the hydrolyzable silyl group of the component (A). The component (B) may also contain a component that activates the catalyst.

[0019] Specific examples of organozinc catalysts include, but are not limited to, zinc acrylate, zinc acetate, zinc citrate, zinc salicylate, zinc oxalate, zinc adipate, zinc carbamate, zinc phthalocyanine, zinc thiolate, zinc stearate, zinc naphthenate, zinc decanoate, zinc butyrate, zinc neodecanoate, zinc isobutyrate, zinc benzoate, zinc octoate, zinc 2-ethylhexanoate, zinc octoate, zinc naphthenate, zinc hexacyanocobaltate complex, and 1-methylimidazole-bis(2-hexanoate)zinc complex.

[0020] Examples of commercial products of component (B) include, but are not limited to, the K-KAT series manufactured by King Industries (670, XK-648, XK-635, XK-614, XK-661, XK-633, etc.).

[0021] The moisture-curable resin composition according to the present invention preferably contains 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and most preferably 0.07 to 3 parts by mass of component (B) per 100 parts by mass of component (A). When the content of component (B) is 0.01 part by mass or more, the initial adhesive strength is improved, and when the content of component (B) is 10 parts by mass or less, the coolant resistance is excellent.

[0022] The component (C) that can be used in the present invention is (C-1) a monoamine compound having an alkyl group of 7 to 20 carbon atoms and / or (C-2) a diamine compound in which an alkyl group having less than 5 carbon atoms is directly bonded to the nitrogen atom. The reaction of component (C) with component (D), described below, improves the coolant resistance of the cured product according to the present invention. In (C-1), the alkyl group having 7 to 20 carbon atoms may have a linear or branched structure. The nitrogen atom of the monoamine in (C-1) may have one or more alkyl groups having 7 to 20 carbon atoms, and from the viewpoint of initial adhesive strength, it preferably has one alkyl group having 7 to 20 carbon atoms. In (C-1), the alkyl group having 7 or more carbon atoms increases electron donation to the amino group, and it is believed that (C-1) can preferentially react with the epoxy group (glycidyl group) of component (D), described below, over the reaction with the hydrolyzable silyl group (e.g., alkoxysilyl group) of component (A). In (C-1), by having 20 or less carbon atoms, the reaction product between (C-1) and component (D) does not become too large and is more likely to migrate toward the interface, which is thought to contribute to coolant resistance. Examples of (C-1) include, but are not limited to, 1-aminoheptane, 1-aminooctane, 1-aminononane, 1-aminodecane, 2-methylhexylamine, 2-ethylhexylamine, 2-propylhexylamine, 2-butylhexylamine, 3-ethylhexylamine, 3-propylhexylamine, and 3-butylhexylamine. In (C-2), it is sufficient that one or more alkyl groups having less than 5 carbon atoms (4 or less) are directly bonded to the nitrogen atom of the diamine, and from the viewpoint of coolant resistance, it is preferable that two alkyl groups are directly bonded to the nitrogen atom of the diamine. "Direct" refers to a bond without any other atoms between the nitrogen atom and the alkyl group. In (C-2), the number of carbon atoms in the alkyl group may be less than 5 (4 or less), and from the viewpoint of adhesive strength, it is more preferably less than 3 (2 or less), and most preferably less than 2 (1). In (C-2), when the number of carbon atoms in the alkyl group is less than 5 (4 or less), the reaction product of (C-2) and component (D) does not become too bulky, and it is thought that this makes it easier to migrate to the vicinity of the interface, which can contribute to coolant resistance.Examples of (C-2) include, but are not limited to, 3-diethylaminopropylamine, 4-diethylaminobutylamine, 5-diethylaminopentylamine, 3-dimethylaminopropylamine, 4-dimethylaminobutylamine, 5-dimethylaminopentylamine, 1,3-bis(methylamino)propane, 1,3-bis(ethylamino)propane, and N,N-dibutyl-1,3-propanediamine.

[0023] The moisture-curable resin composition according to the present invention preferably contains 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass, and most preferably 1 to 10 parts by mass of component (C) per 1 part by mass of component (B). When the content of component (C) is 0.1 part by mass or more, the coolant resistance of the cured product according to the present invention is improved. When the content of component (C) is 20 parts by mass or less, the storage stability of the moisture-curable resin composition according to the present invention is improved.

[0024] The component (D) that can be used in the present invention is a silane coupling agent having an epoxy group (excluding the component (A)). A silane coupling agent is a compound having one of the above-mentioned hydrolyzable silyl groups in the molecule. The hydrolyzable silyl group is most preferably an alkoxysilyl group. Furthermore, the component (D) preferably contains one epoxy group in the molecule. Addition of the component (D) increases the initial adhesive strength of the moisture-curable resin composition according to the present invention, and also improves the coolant resistance of the cured product according to the present invention after curing.

[0025] Specific examples of component (D) include, but are not limited to, 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropylmethyldiethoxysilane. Commercially available products of component (D) include, but are not limited to, KBM-403 and KBE-402 manufactured by Shin-Etsu Chemical Co., Ltd.

[0026] The moisture-curable resin composition according to the present invention preferably contains 0.1 to 11 parts by mass, more preferably 0.5 to 9 parts by mass, and most preferably 1 to 7 parts by mass of component (D) per part by mass of component (C). When the content of component (D) is 0.1 parts by mass or more, the coolant resistance of the cured product according to the present invention after curing can be improved. When the content of component (D) is 11 parts by mass or less, the moisture-curable resin composition according to the present invention exhibits an improved reaction rate and improved initial bond strength.

[0027] The moisture-curable resin composition according to the present invention may contain, as component (E), at least one of (e1) a compound having at least one group selected from the group consisting of a phenyl group, a vinyl group, and an alkyl group and one hydrolyzable silyl group, and (e2) a tetraalkoxysilane compound, as long as the object of the present invention is not impaired. The compound (e1) is a compound having at least one group selected from the group consisting of a phenyl group, a vinyl group, and an alkyl group and one hydrolyzable silyl group in the molecule. The addition of component (E) provides excellent adhesion to aluminum. Among the above, component (E) is preferably a compound having at least one alkyl group and one hydrolyzable silyl group, as this provides good rapid moisture-induced curing properties.

[0028] Here, the alkyl group in compound (e1) is preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, and even more preferably an alkyl group having 1 to 4 carbon atoms. The alkyl group may be linear, branched, or cyclic. The alkyl group is preferably a linear alkyl group. The hydrolyzable silyl group in compound (e1) can be the same as the hydrolyzable silyl group in component (A). The alkoxy group in the tetraalkoxysilane compound (e2) is preferably an alkoxy group having 1 to 10 carbon atoms, more preferably an alkoxy group having 1 to 6 carbon atoms, and even more preferably an alkoxy group having 1 to 4 carbon atoms. The alkoxy group may be linear, branched, or cyclic. The alkoxy group is preferably a linear alkoxy group.

[0029] In the compound (e1), examples of compounds having at least one phenyl group and one hydrolyzable silyl group include phenyltrimethoxysilane, diphenyldimethoxysilane, and phenyltriethoxysilane. Examples of compounds having at least one vinyl group and one hydrolyzable silyl group include vinyltrimethoxysilane and vinyltriethoxysilane. Examples of compounds having at least one alkyl group and one hydrolyzable silyl group include dimethyldimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, and hexyltrimethoxysilane. Examples of (e2) tetraalkoxysilane compounds include ethyl silicate, propyl silicate, and butyl silicate. Component (E) may be used alone or in combination of two or more.

[0030] In the moisture-curable resin composition according to the present invention, the amount (content) of component (E) added is preferably 0.01 to 30 parts by mass, more preferably 0.5 to 20 parts by mass, even more preferably 0.7 to 15 parts by mass, particularly preferably 1 to 10 parts by mass, and most preferably 1.5 to 5 parts by mass, relative to 100 parts by mass of component (A). By being within the above range, the moisture-curable resin composition has excellent initial bond strength.

[0031] As long as the properties of the moisture-curable resin composition according to the present invention and the physical properties of the cured product according to the present invention are not impaired, other components besides the essential components (A) to (D) and the optional component (E) may be added to adjust these properties. Examples of other components include silane coupling agents other than component (D), inorganic fillers, organic fillers, antioxidants, antiaging agents, plasticizers, physical property adjusters, color powders, etc.

[0032] An inorganic filler can be added to the moisture-curable resin composition of the present invention for purposes such as viscosity adjustment and toughness improvement. Examples of inorganic fillers include, but are not limited to, silica powder, fumed silica powder, calcium carbonate powder (heavy calcium carbonate powder, light calcium carbonate powder, etc.), alumina powder, and talc powder. The inorganic fillers may be used alone or in combination of two or more. The powder surface may be treated or untreated. Surface-treated powders are preferably surface-treated because they are easier to knead into the moisture-curable resin composition. Examples of surface treatment agents include fatty acids such as stearic acid, silane-based coupling agents, titanium-based coupling agents, and aluminum-based coupling agents. Considering nozzle clogging during dispense application, the average particle size of the inorganic filler is preferably 0.001 to 50 μm. The average particle size of the inorganic filler can be measured by observation with an electron microscope or a laser diffraction / scattering measurement device using dynamic light scattering. Here, the average particle size refers to the 50% average particle size measured with a laser diffraction / scattering measuring device when it is on the order of μm, and refers to the average particle size observed with an electron microscope when it is on the order of nm. The amount (content) of the inorganic filler added is not particularly limited, but is preferably 50 to 150 parts by mass per 100 parts by mass of component (A). When two or more types of inorganic fillers are contained, the amount (content) of the inorganic fillers added is the total amount.

[0033] The calcium carbonate powder contains calcium carbonate powder treated with a fatty acid for the purpose of improving ease of kneading into the moisture-curable resin composition. From the viewpoint of initial adhesive strength, the moisture-curable resin composition according to the present invention preferably contains calcium carbonate treated with a fatty acid. Commercially available calcium carbonate powders include, but are not limited to, Kalfain Series 200M manufactured by Maruo Calcium Co., Ltd., Softon 1800 manufactured by Shiraishi Calcium Co., Ltd., and NCC#110 manufactured by Nitto Funka Kogyo Co., Ltd.

[0034] Examples of fumed silica powder include, but are not limited to, hydrophilic types in which silanol remains on the untreated surface, and hydrophobic types in which silanol is treated with dimethyldichlorosilane, dimethylsilicone, or the like to hydrophobize the silica surface. In the moisture-curable resin composition according to the present invention, the fumed silica powder is preferably dimethylsilicone-treated fumed silica powder from the viewpoint of initial adhesive strength. Specific examples of hydrophilic types include Aerosil 90, 130, 150, 200, 255, 300, and 380 manufactured by Nippon Aerosil Co., Ltd. Specific examples of hydrophobic products include Aerosil R972 (dimethyldichlorosilane treated), R974 (dimethyldichlorosilane added), R104 (octamethylcyclotetrasiloxane treated), R106 (octamethylcyclotetrasiloxane treated), R202 and RY200 (polydimethylsiloxane treated), R805 (octylsilane treated), R812 (hexamethyldisilazane treated), R816 (hexadecylsilane treated), and R711 (methacrylsilane treated), all manufactured by Nippon Aerosil Co., Ltd. Specific examples of other fumed silica powder products include the Cabosil series, which are fumed silica products manufactured by Cabot Corporation.

[0035] In the moisture-curable resin composition according to the present invention, from the viewpoint of initial adhesive strength, it is preferable to use a combination of fatty acid-treated calcium carbonate powder and hydrophobic fumed silica powder. The mass ratio of the fatty acid-treated calcium carbonate powder to the hydrophobic fumed silica powder (fatty acid-treated calcium carbonate powder:hydrophobic fumed silica powder) is preferably 60:40 to 99:1, more preferably 70:30 to 98:2, and most preferably 80:20 to 97:3.

[0036] The moisture-curable resin composition according to the present invention may contain an antioxidant. The purpose of this is to prevent deterioration of the cured product due to the external environment. Examples of antioxidants include, but are not limited to, phenol-based antioxidants, thioether-based antioxidants, phosphorus-based antioxidants, and nitroxide-based antioxidants. Taking into account resistance to coolants, the antioxidant is preferably a thioether-based antioxidant. The amount (content) of the antioxidant added is preferably 0.1 to 5.0 parts by mass per 100 parts by mass of component (A).

[0037] The moisture-curable resin composition according to the present invention may contain a plasticizer. The purpose of the plasticizer may include imparting flexibility and pliability to the cured product. From the viewpoint of workability, the plasticizer is preferably liquid at 25°C. The plasticizer is not particularly limited as long as it is compatible with component (A). Specific examples of plasticizers include propylene carbonate, DOS (di-2-ethylhexyl sebacate), DOP (dioctyl phthalate), DINP (diisononyl phthalate), DIDP (diisodecyl phthalate), DBP (dibutyl phthalate), DMS (dimethyl maleate), DOA (dioctyl adipate), DINA (diisononyl adipate), TCP (tricresyl phosphate), DMS (dimethyl maleate), and (meth)acrylic polymers that are liquid at 25°C, but are not limited thereto. From the viewpoint of not reducing the initial adhesive strength, the moisture-curable resin composition according to the present invention preferably contains a plasticizer having a diester structure, more preferably dimethyl maleate. The plasticizer may be used alone or in combination of two or more.

[0038] The moisture-curable resin composition of the present invention may be a one-component type containing all of the components, or a two-component type in which each component is separated into two and then mixed to form a single component. Separating the components into two, component A and component B, can suppress unnecessary reactions during storage and improve storage stability, so the moisture-curable resin composition of the present invention is preferably a two-component type. The moisture-curable resin composition of the present invention, which is a two-component type, contains component A containing component (B) and component (C), and component B containing component (D). Component (A) and other components, such as fillers (inorganic fillers and organic fillers), plasticizers, and antioxidants, may be contained in both component A and component B, or in either component A or component B. Whether the moisture-curable resin composition of the present invention is a one-component or two-component type, it can be cured by leaving it in an environment of 20 to 27°C and 30 to 70% RH, or by leaving it in an atmosphere of 30 to 100°C. The curing (standing) time is 10 minutes to 10 days.

[0039] When the moisture-curable resin composition according to the present invention is a two-component mixture type, the method for mixing component A and component B is not particularly limited as long as they can be mixed uniformly. Examples of the mixing method include a method using a mixer, a planetary stirrer, or the like, a method of manually stirring using a glass rod, or a method using a static mixer. Since the moisture-curable resin composition according to the present invention is a two-component mixture type, and components A and B react when mixed, it is preferable to mix them at 40°C or less.

[0040] The agent A of the moisture-curable resin composition of the present invention, which is a two-component mixture type, preferably contains the component (A) in addition to the components (B) and (C). In the agent A, the amount (content) of the component (B) added is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and most preferably 0.07 to 3 parts by mass, relative to 50 parts by mass of the component (A). The amount (content) of the component (C) added is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 7 parts by mass, and most preferably 0.05 to 4 parts by mass, relative to 50 parts by mass of the component (A). By being within the above range, an agent A with high storage stability can be obtained.

[0041] When the agent A of the moisture-curable resin composition according to the present invention is a two-component mixture type and contains the (E) component, the amount (content) of the (E) component added is preferably 0.01 to 30 parts by mass per 50 parts by mass of the (A) component. When the agent A contains an inorganic filler, the amount (content) of the inorganic filler added is preferably 25 to 75 parts by mass per 50 parts by mass of the (A) component. When the agent A contains an antioxidant, the amount (content) of the antioxidant added is preferably 0.05 to 2.5 parts by mass per 50 parts by mass of the (A) component. When the agent A contains a plasticizer, the amount (content) of the plasticizer added is preferably 1 to 40 parts by mass per 50 parts by mass of the (A) component. By being within the above range, an agent A with excellent workability and high storage stability can be obtained.

[0042] The component B of the moisture-curable resin composition of the present invention, which is a two-component mixture, preferably contains the component (A) in addition to the component (D). The amount (content) of the component (D) added is preferably 0.1 to 11 parts by mass, more preferably 0.5 to 9 parts by mass, and most preferably 1 to 7 parts by mass, per 50 parts by mass of the component (A). By keeping the amount within the above range, it is possible to obtain the component B with high storage stability, and when mixed with the component A and cured, the cured product of the present invention can have high coolant resistance.

[0043] When the component B of the moisture-curable resin composition according to the present invention is a two-component mixture type, the amount (content) of the inorganic filler added is preferably 30 to 90 parts by mass per 50 parts by mass of the component (A). When the component B contains an antioxidant, the amount (content) of the antioxidant added is preferably 0.05 to 2.5 parts by mass per 50 parts by mass of the component (A). When the component B contains a plasticizer, the amount (content) of the plasticizer added is preferably 1 to 40 parts by mass per 50 parts by mass of the component (A). By being within the above range, a component B with excellent workability and high storage stability can be obtained.

[0044] In the moisture-curable resin composition of the present invention, which is a two-component mixture type, the amount of component B is preferably 10 to 300 parts by mass, more preferably 30 to 200 parts by mass, and even more preferably 50 to 150 parts by mass, based on 100 parts by mass of component A. The amount of component B is preferably 10 to 300 ml, more preferably 30 to 200 ml, and even more preferably 50 to 150 ml, based on 100 ml of component A. By being within the above range, the initial adhesive strength is excellent.

[0045] Another aspect of the present invention is a cured product obtained by curing the moisture-curable resin composition described above. In one embodiment, the cured product is obtained by mixing the components A and B constituting the two-component moisture-curable resin composition, and curing the two-component moisture-curable resin composition.

[0046] The moisture-curable resin composition according to the present invention has excellent adhesion to aluminum and is therefore preferably used in various applications such as adhesives, sealants, potting agents, coating agents, thermally conductive resins, flame-retardant resins, and conductive pastes, and is particularly used in the above applications relating to automobile parts, electrical and electronic parts, building materials, and the like.

[0047] Examples of automotive parts include radiators, PCU cooling systems, oil pans, transmissions, oil pressure switches, air flow meters, cam position sensors, water temperature sensors, crank position sensors, intake air temperature sensors, vehicle speed sensors, automotive electronic boards, nickel batteries, Li batteries, fuel cells, etc. In automotive parts, the moisture-curable resin composition according to the present invention can be suitably used as an adhesive, sealant, potting agent, etc.

[0048] In automotive applications, the coolant in a water-cooled cooling system contains chemicals such as LLC (registered trademark), and is also called antifreeze, radiator fluid, or coolant. The main components of the coolant include ethylene glycol and propylene glycol, with other components including phosphate-chloride corrosion inhibitors, rust inhibitors, and water. Deterioration of the cured product by the coolant can lead to a deterioration in sealing properties, which can cause the cured product to peel off from the adherend or crack, potentially resulting in coolant leakage. The cured product of the present invention is resistant to coolants and is suitable for use in sealing coolants. Resistance to coolants refers to the absence of coolant leakage even when the coolant and the cured product of the present invention are in contact for a long period of time.

[0049] Aluminum alloys, polyphenylene sulfide resins, etc. are used for automobile parts because of their heat resistance and light weight. The moisture-curable resin composition according to the present invention is suitable for use with aluminum and / or polyphenylene sulfide because of its excellent adhesiveness to aluminum, polyphenylene sulfide resins, etc.

[0050] The sealing method using the moisture-curable resin composition according to the present invention is not particularly limited. Typical examples of sealing methods include FIPG (formed-in-place gasket), CIPG (cured-in-place gasket), MIPG (molded-in-place gasket), and liquid injection molding. The moisture-curable resin composition according to the present invention can be suitably used as FIPG.

[0051] FIPG is a technique for adhesively sealing a flange of a sealed part by applying the moisture-curable resin composition of the present invention using an automatic coating device or the like, and then bonding the flange to the other flange and curing the moisture-curable resin composition. More specifically, this is a method for sealing at least a portion of the space between at least two flanges of a sealed part having at least two flanges, comprising the steps of: applying the moisture-curable resin composition of the present invention to the surface of at least one of the at least two flanges; bonding the one flange coated with the moisture-curable resin composition to the other flange via the moisture-curable resin composition; and curing the curable resin composition to seal at least a portion of the space between the at least two flanges.

[0052] CIPG is a technique in which a bead of the moisture-curable resin composition of the present invention is applied to a flange of a sealed part using a screen printing applicator, an automatic applicator, or the like, and the moisture-curable resin composition is cured to form a gasket, which is then bonded to the other flange for compression sealing. More specifically, this is a method for sealing at least a portion of the gap between at least two flanges of a sealed part having at least two flanges, comprising the steps of: applying the moisture-curable resin composition of the present invention to at least one of the at least two flanges; curing the applied moisture-curable resin composition to form a gasket made of the cured product of the moisture-curable resin composition; and placing the other flange on the gasket and crimping the one flange coated with the moisture-curable resin composition to the other flange via the gasket to seal at least a portion of the gap between the at least two flanges.

[0053] MIPG is a technique in which a mold is pressed against the flange of the part to be sealed, a moisture-curable resin composition is injected into the cavity formed between the mold and the flange, and cured to form a gasket, which is then bonded to the other flange for compression sealing. After the gasket is formed, it is preferable to coat the mold with a fluorine-based, silicone-based, or other mold release agent in advance to make it easier to remove from the mold. More specifically, the present invention relates to a method for sealing at least a portion of the gap between at least two flanges of a sealed part having at least two flanges, the method comprising the steps of: placing a gasket-forming mold on at least one of the at least two flanges; injecting the moisture-curable resin composition according to the present invention into at least a portion of the gap between the gasket-forming mold and the one flange on which the mold is placed; curing the moisture-curable resin composition to form a gasket made of the cured product of the moisture-curable resin composition; removing the mold from the one flange; placing the other flange on the gasket and crimping the one flange and the other flange together via the gasket, thereby sealing at least a portion of the gap between the at least two flanges.

[0054] Examples 1 to 4 and Comparative Examples 1 to 3 The following components were prepared to prepare moisture-curable resin compositions.Component (A): Organic polymer having a hydrolyzable silyl group - A polymer whose main skeleton is a polymer of an acrylic monomer and has two methyldimethoxysilyl groups in the molecule (KANEKA XMAP (registered trademark) SA110S, manufactured by Kaneka Corporation, viscosity: 500 Pa·s (23°C)) Component (B): Organic zinc catalyst - Organic zinc catalyst (XK-633, manufactured by King Industries) Component (B'): Organic metal catalyst other than component (B) - Titanium diisopropoxybis(ethyl acetoacetate) (Orgatix TC-750, manufactured by Matsumoto Fine Chemical Co., Ltd.) Component (C-1): Monoamine compound having an alkyl group having 7 to 20 carbon atoms - 1-aminooctane (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) - 2-ethylhexylamine (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) Component (C-2): a diamine compound in which an alkyl group having less than 5 carbon atoms is directly bonded to a nitrogen atom 3-diethylaminopropylamine (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) N,N-dibutyl-1,3-propanediamine (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) Component (C'): a monoamine compound other than component (C) 1-aminopropane (reagent, manufactured by Tokyo Chemical Industry Co., Ltd.) Component (D): a silane coupling agent having an epoxy group 3-glycidoxypropyltrimethoxysilane (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) Component (D'): a silane coupling agent other than component (D) N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.) Component (E): (e1) a compound having at least one group selected from the group consisting of a phenyl group, a vinyl group, and an alkyl group, and one hydrolyzable silyl group Methyltrimethoxysilane (KBM-13 (manufactured by Shin-Etsu Chemical Co., Ltd.) Inorganic filler: Hydrophobic calcium carbonate powder having an average particle size of 2.1 μm, apparent specific gravity of 0.61 g / ml, and DOP absorption of 16 ml / 100 g (NCC#110 manufactured by Nitto Funka Kogyo Co., Ltd.); Dimethyl silicone-treated fumed silica powder having an average particle size of 12 nm (AEROSIL RY200 manufactured by Nippon Aerosil Co., Ltd.) Plasticizer: Dimethyl maleate (DMS manufactured by Toyokuni Oil Mills Co., Ltd.) Antioxidant: Thioether-based antioxidant (liquid at 25°C) (ADK STAB AO-26 manufactured by ADEKA Corporation).

[0055] The moisture-curable resin compositions of Examples 1 to 4 and Comparative Examples 1 to 3 were prepared by the following method. First, half of the (A) component and half of the antioxidant were weighed into a stirring kettle as Agent A, and after stirring for 1 minute, half of the calcium powder was weighed and added to the stirring kettle. The mixture was stirred at 80°C for 90 minutes while vacuum degassing. Component (B) (or (B') component), component (C) (or (C') component), component (E) and half of the plasticizer were weighed and added to the stirring kettle. The mixture was stirred for 30 minutes while vacuum degassing to prepare Agent A. Next, the remaining component (A) and the remaining antioxidant were weighed and added to another stirring kettle as Agent B. After stirring for 1 minute, the fumed silica powder and the remaining calcium powder were weighed and added to the stirring kettle. The mixture was stirred at 80°C for 90 minutes while vacuum degassing. Component (D) (or (D') component) and the remaining plasticizer were added to the stirring kettle. The mixture was stirred for 1 hour while vacuum degassing to prepare Agent B. A moisture-curable resin composition was obtained by mixing 107.3 parts by mass of agent B with 100 parts by mass of agent A. Detailed blending amounts are shown in Table 1, and all values ​​are expressed in parts by mass. The blending amounts shown in Table 1 are the blending amounts after mixing agents A and B.

[0056] The test methods used in the examples and comparative examples in Table 1 are as follows.

[0057] [Measurement of Tensile Shear Adhesion Strength] Using aluminum members measuring 25 mm wide x 100 mm long x 1 mm thick, two members were bonded together with a moisture-curable resin composition over a 10 mm x 25 mm adhesive area (clearance 1 mm). The moisture-curable resin composition was cured by leaving the test piece in an atmosphere of 23 ° C and 50% RH for 7 days to prepare a test piece. The test piece was pulled at 50 mm / min using a tensile tester, and the maximum strength was recorded as "initial adhesive strength (MPa)". Considering peeling from the adherend, the initial tensile shear adhesive strength is preferably 0.6 MPa or more, more preferably 0.8 MPa. The test piece was then immersed in an aqueous solution containing 50% by volume of ethylene glycol (a reagent manufactured by Tokyo Chemical Industry Co., Ltd.), the main component of the coolant, and left at 120 ° C for 240 hours. The test piece was removed and the immersion liquid was wiped off. After leaving it at 23°C for 2 hours, the tensile shear adhesive strength was measured under the same conditions as above, and this was recorded as "adhesive strength after immersion (MPa)". Details of the tensile test were in accordance with JIS K 6249:2003. The "peel state" was confirmed visually according to the following evaluation criteria. The post-immersion adhesive strength is preferably 1.4 MPa or more. In order to maintain sealing properties against the immersion liquid, the peel state is preferably "○". Note that moisture-curable resin compositions that could not be measured due to poor curing are marked with "-". <Evaluation criteria> ○: Cohesive failure occurred on 50% to 100% of the peeled surface ×: Cohesive failure occurred on 0% to less than 50% of the peeled surface

[0058]

[0059] According to Table 1, it can be seen that the cured products of the moisture-curable resin compositions of Examples 1 to 4 have good initial adhesive strength and coolant resistance. In the cured product of the moisture-curable resin composition of Comparative Example 1, component (C') was used instead of component (C), but the peeling state after immersion in coolant was poor. In addition, in the cured product of the moisture-curable resin composition of Comparative Example 2, component (B') was used instead of component (B), but the product did not cure. In the cured product of the moisture-curable resin composition of Comparative Example 3, component (D') was used instead of component (D), but the peeling state after immersion in coolant was poor.

[0060] Further, the moisture-curable resin compositions of Examples 1 to 3 and Comparative Example 1 were subjected to additional tests.

[0061] [Tensile Shear Adhesion Strength Measurement 2] Using aluminum members measuring 25 mm wide x 100 mm long x 1 mm thick, two members were bonded together with a moisture-curable resin composition over a 10 mm x 25 mm adhesive area (clearance 1 mm). Test pieces were prepared by leaving the test pieces in an atmosphere of 23 ° C and 50% RH for 7 days to cure the moisture-curable resin composition. The test pieces were immersed in an aqueous solution containing 50% by volume of ethylene glycol (reagent manufactured by Tokyo Chemical Industry Co., Ltd.), the main component of the coolant liquid, and left at 120 ° C for 500 hours. The test pieces were removed and wiped clean, then left at 23 ° C for 2 hours, and then pulled at 50 mm / min using a tensile tester. The maximum strength was recorded as "Al / Al post-immersion adhesive strength (MPa)". Details of the tensile test were in accordance with JIS K 6249:2003. In addition, the tensile shear adhesive strength was measured under the same conditions as above using a polyphenylene sulfide (PPS) member measuring 25 mm wide x 100 mm long x 2 mm thick, and this was taken as "PPS / PPS post-immersion adhesive strength (MPa)". The "peel state" was confirmed visually according to the following evaluation criteria. The post-immersion adhesive strength for Al / Al is preferably 1.2 MPa or more. The post-immersion adhesive strength for PPS / PPS is preferably 1.4 MPa or more. In order to maintain sealing properties against the immersion liquid, the peel state is preferably "○". <Evaluation criteria> ○: Cohesive failure occurs over 50% to 100% of the peeled surface ×: Cohesive failure occurs over 0% to less than 50% of the peeled surface

[0062]

[0063] Table 2 also shows that the moisture-curable resin composition of the present invention has good coolant resistance to both aluminum and polyphenylene sulfide. This test corresponds to use under harsh conditions for a sealant that comes into contact with coolant, and there is concern that the cured product may peel off from the adherend or deteriorate, resulting in deterioration of sealing properties and liquid leakage. The moisture-curable resin composition of the present invention and its cured product are sealants that can be used stably in such important areas.

[0064] The moisture-curable resin composition of the present invention has excellent adhesion to aluminum and is resistant to coolants, and is therefore suitable for a variety of applications, such as adhesives, sealants, potting agents, coating agents, thermally conductive resins, flame-retardant resins, and conductive pastes, etc. Therefore, the composition is industrially useful because it can be applied in a wide range of fields.

[0065] This application is based on Japanese Patent Application No. 2023-192774, filed on November 13, 2023, the disclosure of which is incorporated herein by reference in its entirety.

Claims

1. A moisture-curable resin composition comprising the following components (A) to (D): component (A): an organic polymer having a hydrolyzable silyl group; component (B): an organozinc catalyst; component (C): (C-1) a monoamine compound having an alkyl group having 7 to 20 carbon atoms and / or (C-2) a diamine compound in which an alkyl group having less than 5 carbon atoms is directly bonded to a nitrogen atom; and component (D): a silane coupling agent having an epoxy group.

2. The moisture-curable resin composition according to claim 1, wherein the main skeleton of the organic polymer of component (A) is a (meth)acrylic polymer.

3. The moisture-curable resin composition according to claim 1, wherein the hydrolyzable silyl group of the component (A) is a dialkoxysilyl group.

4. The moisture-curable resin composition according to claim 1, comprising 0.1 to 20 parts by mass of said component (C) per 1 part by mass of said component (B).

5. The moisture-curable resin composition according to claim 1, comprising 0.1 to 11 parts by mass of said component (D) per 1 part by mass of said component (C).

6. A two-part moisture-curable resin composition comprising an A component containing the following components (A) to (C) and a B component containing the following component (D): component (A): an organic polymer having a hydrolyzable silyl group; component (B): an organic zinc catalyst; component (C): (C-1) a monoamine compound having an alkyl group having 7 to 20 carbon atoms and / or (C-2) a diamine compound in which an alkyl group having less than 5 carbon atoms is directly bonded to a nitrogen atom; and component (D): a silane coupling agent having an epoxy group.

7. A cured product obtained by curing the moisture-curable resin composition according to claim 1 or 6.

8. The moisture-curable resin composition according to claim 1 or 6, wherein the adherend is aluminum and / or polyphenylene sulfide.

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