Moisture-curable resin composition

Abstract

To provide a moisture-curable resin composition which can be easily disassembled at any desired timing, while having adhesiveness and sealability.SOLUTION: [1] A moisture-curable resin composition contains the following components (A) to (C). Component (A): an organic polymer having two or more alkoxysilyl groups. Component (B): thermally expansible particles. Component (C): an organometallic catalyst.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a moisture-curable resin composition that is excellent in dismantling ability.

[0002] In recent years, aluminum members have been widely used in automotive parts to reduce their weight. Furthermore, there is a demand for sealants for automotive parts that can be cured at room temperature in order to improve production efficiency. Patent Document 1 discloses a moisture-curable resin composition that has excellent adhesion to aluminum, as well as excellent moisture-induced rapid curing and thick-film curing properties. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2022 / 064931 publication Summary of the Invention [Problem to be solved by the invention]

[0004] On the other hand, when adhesion failure occurs or when reusing lithium-ion batteries in automobiles, rework is required, but peeling off the cured material has been difficult. Conventional methods include peeling off the material using a crane or cutting it with piano wire, but these methods require specialized equipment and have the drawback of making it difficult to reuse the workpiece because the peeled-off adherend deforms.

[0005] As a result of intensive research to achieve the above object, the inventors discovered a method for producing a moisture-curable resin composition that has adhesive and sealing properties while being easily dismantled at any time, and thus completed the present invention. [Means for solving the problem]

[0006] The gist of the present invention will now be described. [1] A moisture-curable resin composition comprising the following components (A) to (C): Component (A): an organic polymer having two or more alkoxysilyl groups Component (B): Thermally expandable particles (C) Component: Organometallic catalyst [2] The moisture-curable resin composition according to [1], wherein the component (B) is a microcapsule-type heat-expandable particle. [3] The moisture-curable resin composition according to [1] or [2], comprising 10 parts by mass or more and 200 parts by mass or less of the (B) component per 100 parts by mass of the (A) component. [4] The moisture-curable resin composition according to [1] or [2], wherein the component (C) is an organic zinc catalyst. [5] The moisture-curable resin composition according to [1] or [2], further comprising a plasticizer as component (D). [6] The moisture-curable resin composition according to [1] or [2], further comprising a silane compound having an alkoxysilyl group (excluding the component (A)) as component (E). [7] The moisture-curable resin composition according to [1] or [2], further comprising an inorganic filler as the component (F). [8] The moisture-curable resin composition according to [1] or [2], comprising 50 to 200 parts by mass of the component (F) per 100 parts by mass of the component (A). [9] A sealant or adhesive comprising the moisture-curable resin composition having thermal dismantling properties described in [1] or [2].

[10] A cured product obtained by applying the moisture-curable resin composition having thermal dismantling properties described in [1] or [2] to an adherend and curing it.

[11] A disassembly method for disassembling the cured product according to

[10] from an adherend by heating. [Effects of the Invention]

[0007] The present invention provides a moisture-curable resin composition that has high adhesiveness and sealing properties and excellent dismantling properties. Here, dismantling properties refer to the ease with which adherends bonded and sealed with the moisture-curable resin composition of the present invention can be easily separated by heating. DETAILED DESCRIPTION OF THE INVENTION

[0008] The present invention will be described in detail below. In the present specification, the expression "X to Y" means that X and Y are numerical values, and X and Y are used to mean the lower limit and upper limit, respectively. In addition, in the present invention, (meth)acrylate means both acrylate and methacrylate.

[0009] The component (A) that can be used in the present invention is an organic polymer having two or more alkoxysilyl groups in the molecule. In particular, because of its excellent sealing properties, it is preferable that the organic polymer be linear and have alkoxysilyl groups at both ends. The alkoxysilyl groups undergo a crosslinking reaction with the component (C) described below in response to moisture (water) that enters the composition from the outside air. Specific examples of the component (A) include the component (A-1) in which the organic polymer of the component (A) is polyoxyalkylene, and the component (A-2) in which the organic polymer of the component (A) is poly(meth)acrylate. Considering dismantling properties, the component (A) preferably contains the component (A-1), and more preferably is the component (A-1).

[0010] Examples of the alkoxysilyl group of component (A) include trialkoxysilyl groups such as trimethoxysilyl, triethoxysilyl, triisopropoxysilyl, and triphenoxysilyl, dialkoxysilyl groups such as methyldimethoxysilyl and methyldiethoxysilyl, and monoalkoxysilyl groups such as dimethylmethoxysilyl and dimethylethoxysilyl. Considering the effect of achieving excellent heat resistance in the cured product, dialkoxysilyl and trialkoxysilyl groups are preferred, and trimethoxysilyl and triethoxysilyl groups are most preferred.

[0011] From the viewpoint of ease of handling, component (A) is preferably liquid at 25°C. The viscosity of component (A) at 25°C is preferably 0.5 to 500 Pa·s, more preferably 1 to 200 Pa·s, and most preferably 3 to 150 Pa·s. A viscosity of 0.5 to 500 Pa·s provides even better sealing properties. Unless otherwise specified, the viscosity was measured at 25°C using a cone-plate viscometer in accordance with JIS K6833-1:2008.

[0012] Commercially available products of the component (A-1) include, but are not limited to, SAT010, SAX115, SAT030, SAT030, SAT200, SAT350, SAT400, SAX220, SAX510, SAX520, SAX530, SAX575, SAX580, SAX710, SAX720, SAX725, SAX770, S203, S303, S203H, S303H, S943S, S911S, MA440, MA447, MA451, MA903, MA903M, MA904, S943, MAX923, and MAX951 manufactured by Kaneka Corporation.

[0013] Commercially available products of the component (A-2) include SA110S, SA100S, SA120S, and OR110S manufactured by Kaneka Corporation, but are not limited to these.

[0014] Component (B) of the present invention is a thermally expandable particle. Component (B) can be any conventionally known material that expands in volume upon heating. This does not include expanded thermally expandable particles. By using component (B) in the present invention, the cured product of the present invention can be made thermally dismantlable. Specifically, the moisture-curable resin composition of the present invention is applied to adherends, and the adherends are bonded and cured at a temperature lower than the expansion initiation temperature of component (B). Next, by heating the cured product at a temperature higher than the expansion initiation temperature of component (B) at any desired timing, the cured coating expands, creating voids between the adherends, allowing the adherends to be easily dismantled.

[0015] Known thermally expandable particles that can be used in the present invention include, for example, inorganic compounds with thermal expansion such as ammonium carbonate, ammonium bicarbonate, ammonium nitrite, ammonium borohydride, and azides; organic compounds with thermal expansion such as fluorinated alkanes such as trichloromonofluoromethane, azo compounds such as azobisisobutyronitrile, hydrazine compounds such as paratoluenesulfonylhydrazide, semicarbazide compounds such as p-toluenesulfonylsemicarbazide, triazole compounds such as 5-morpholyl-1,2,3,4-thiatriazole, and N-nitroso compounds such as N,N'-dinitrosoterephthalamide; carbon materials containing a liquid encapsulated between layers of flake graphite that expands upon heating and vaporization; and microcapsule-based thermally expandable particles containing low-boiling hydrocarbon compounds encapsulated in microcapsules. Microcapsule-based thermally expandable particles are particularly preferred in the present invention.

[0016] The average particle size of component (B) can be appropriately selected depending on the workability and application method of the moisture-curable resin composition. The average particle size of the thermally expandable particles, such as microspheres, can be selected, for example, from a range of preferably 1 μm to 100 μm, more preferably 2 μm to 80 μm, and particularly preferably 3 μm to 50 μm. The particle size of the thermally expandable particles may be adjusted during the production process of the thermally expandable particles, or may be adjusted using known techniques (e.g., classification) on commercially available thermally expandable particles. In the present invention, the average particle size refers to the particle size (volume average) at 50% cumulative volume in the particle size distribution determined by, for example, laser diffraction / scattering (also referred to as D50). From the perspective of variation in the expansion onset temperature, it is preferable that the particle size of the thermally expandable particles be uniform. The difference between D10 (the particle size at 10% cumulative volume in the particle size distribution) and D90 (the particle size at 90% cumulative volume in the particle size distribution) and D50 is preferably within 35 μm, and more preferably within 30 μm.

[0017] The microcapsule-based heat-expandable particles are microcapsules with a gas-barrier thermoplastic resin shell containing a low-boiling compound. When heated, the thermoplastic resin shell softens and the low-boiling compound vaporizes, increasing the volume of the microcapsules and causing them to expand into hollow spheres.

[0018] Examples of thermoplastic resins that make up the shells of the microcapsules include vinylidene chloride, acrylonitrile, polystyrene, polymethacrylate, and polyvinyl alcohol. Because thermoplastic resins typically have gas barrier properties, low-boiling substances are retained within the particles even when heated and expanded. Examples of low-boiling compounds encapsulated in the shells include hydrocarbon compounds that are liquid at room temperature and have a boiling point of approximately 100°C, such as isopentane (boiling point approximately 28°C), n-pentane (boiling point approximately 36°C), cyclopentane (boiling point approximately 49°C), n-hexane (boiling point approximately 67°C), isohexane (boiling point approximately 62°C), cyclohexane (boiling point approximately 81°C), 3-methylhexane (boiling point approximately 92°C), n-heptane (boiling point approximately 98°C), isooctane (boiling point approximately 99°C), and petroleum ether (boiling point 40-60°C). Among these, isopentane and n-pentane are particularly suitable, as they are easily gasified.

[0019] In the present invention, the microcapsule-based thermally expandable particles may be commercially available products known in the art. Examples of commercially available microcapsule-based thermally expandable particles include Expancel 053WU40 and 053DU40 (both with an expansion start temperature of 96-103°C), 031WU40 and 031DU40 (both with an expansion start temperature of 80-95°C), 007WU40 (with an expansion start temperature of 91-99°C), 909DU80 (with an expansion start temperature of 120-130°C), 920DU40 (with an expansion start temperature of 123-133°C), and 930DU120 (with an expansion start temperature of 122-132°C), all of which are manufactured by Nippon Phillite Co., Ltd.; and Matsumoto Microsphere F-30 (with an expansion start temperature of 70-80°C), F-36 (with an expansion start temperature of 70-80°C), F-36LV (with an expansion start temperature of 75-85°C), and F-40 (both of which are manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.). Examples of commercially available products include F-8 (expansion start temperature 90 to 100°C), F-50 (expansion start temperature 95 to 105°C), F-65 (expansion start temperature 105 to 115°C), F-190D (expansion start temperature 160 to 170°C), F-100M (expansion start temperature 115 to 125°C), FN-100S (expansion start temperature 125 to 135°C), FN-100SS (expansion start temperature 120 to 130°C), FN-100 (expansion start temperature 120 to 135°C), FN-100M (expansion start temperature 125 to 135°C), FN-100M (expansion start temperature 125 to 135°C), and the Kureha Microsphere series manufactured by Kureha Corporation. These commercially available products may be used alone or in combination of two or more. The expansion starting temperature here refers to the temperature at which the thermally expandable particles start to expand when expanded by the TMA method at a temperature increase rate of 10 to 20°C / min.

[0020] The expansion onset temperature of the thermoexpandable particles of the present invention refers to the temperature at which the thermoexpandable particles begin to expand. From the perspective of the stability of the cured product before disassembly, the temperature at which expansion begins is preferably 70 to 230°C, particularly preferably 100 to 200°C, and most preferably 110 to 180°C. The expansion onset temperature is typically allowed to vary by 20°C, preferably 15°C, and more preferably 10°C, depending on particle variation. In practice, it is difficult to precisely control the temperature of the cured product of the present invention before disassembly, i.e., the temperature present in the narrow gaps between the adherends, just before disassembly. Therefore, a realistic heating condition is to gradually heat from room temperature to a temperature within the above-mentioned expansion onset temperature range or higher, whereby the thermoexpandable particles expand as the temperature increases, resulting in the disassembly of the adherends.

[0021] In the present invention, the (B) component is preferably contained in an amount of 10 parts by mass or more, more preferably 18 parts by mass or more, and most preferably 30 parts by mass or more, per 100 parts by mass of the (A) component. An amount of 10 parts by mass or more enables the adherend to be disassembled in a shorter time. Furthermore, the (B) component is preferably contained in an amount of 200 parts by mass or less, more preferably 150 parts by mass or less, and most preferably 100 parts by mass or less, per 100 parts by mass of the (A) component. By containing 200 parts by mass or less, the adhesiveness of the moisture-curable resin composition of the present invention is not reduced.

[0022] The component (C) that can be used in the present invention is an organometallic catalyst. Component (C) is a catalyst that cures the composition. It is sufficient that component (C) has the effect of promoting dealcoholization condensation between components (A) themselves, between component (A) and a silane compound having an alkoxysilyl group (excluding component (A)) described below, or between silane compounds having an alkoxysilyl group (excluding component (A)). Specific examples of curing catalysts include organotin catalysts, organotitanium catalysts, organozirconium catalysts, and organozinc catalysts. From the perspectives of the variety of catalyst types that can be used, reactivity, and cost, organotin catalysts, organotitanium catalysts, or organozinc catalysts are preferred, and organozinc catalysts are most preferred. Furthermore, because there is a risk of interference between the ligands of each component, which can reduce catalytic activity, it is preferable to use one type of component (C) alone without mixing them.

[0023] Specific examples of organotin catalysts include, but are not limited to, divalent organotin catalysts such as tin octoate and tin naphthenate; tetravalent organotin compounds such as dibutyltin dioctoate, dibutyltin dilaurate, dibutyltin diacetate, dibutyltin dimaleate, dibutyltin distearate, dioctyltin dilaurate, dioctyltin diversatate, dibutyltin oxide, dibutyltin bis(triethoxysilicate), dioctyltin dilaurate, and dibutyltin oxide and phthalate esters; and chelate tin compounds such as dibutyltin bis(acetylacetonate) and other tin-based chelate compounds.

[0024] Specific examples of organic titanium catalysts include, but are not limited to, tetraisopropyl titanate, tetra-n-butyl titanate, butyl titanate dimer, tetraoctyl titanate, titanium acetylacetonate, titanium octylene glycolate, titanium tetraacetylacetonate, titanium ethylacetoacetate, polyhydroxytitanium stearate, titanium lactate, titanium triethanolamine, titanium diisopropoxybis(ethylacetoacetate), etc. Specific examples of organic zirconium catalysts include, but are not limited to, tetra-n-propoxyzirconium, tetra-n-butoxyzirconium, zirconium tetraacetylacetonate, zirconium monobutoxyacetylacetonatebis(ethylacetoacetate), zirconium dibutoxybis(ethylacetoacetate), zirconium tetraacetylacetonate, zirconium tributoxystearate, etc.

[0025] Specific examples of organozinc catalysts include zinc(1-butylimidazole)2(acetate)2, zinc(1-methylimidazole)2(acetate)2, zinc(imidazole)2(acetate)2, zinc(1,2-dimethylimidazole)2(acetate)2, zinc(tetramethylguanidine)2(acetate)2, zinc(DBN)2(acetate)2, zinc(DBU)2(acetate)2, zinc(1-butylimidazole)2(acetate)2, zinc(1-methylimidazole)2(formate)2, zinc(imidazole)2(formate)2, zinc(1,2-dimethylimidazole) Zinc(1-butylimidazole)2(neodecanoic acid)2, Zinc(1-methylimidazole)2(neodecanoic acid)2, Zinc(imidazole)2(neodecanoic acid)2, Zinc(1,2-dimethylimidazole)2(neodecanoic acid)2, Zinc(tetramethylguanidine)2(neodecanoic acid)2, Zinc(DBN)2(neodecanoic acid)2, Zinc(DBU)2(neodecanoic acid)2 and the like.

[0026] Examples of the organic zinc catalyst include a complex compound having zinc (divalent) as the central metal. When the component (C) contains a ligand, examples of the ligand include a carboxylate compound, a β-ketoester compound, and a β-diketone compound, with amine compounds and carboxylate compounds being preferred.

[0027] Examples of the carboxylate compounds include acetic acid, formic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and neodecanoic acid. Examples of the β-ketoester compounds include methyl acetoacetate, ethyl acetoacetate, n-propyl acetoacetate, isopropyl acetoacetate, n-butyl acetoacetate, sec-butyl acetoacetate, and t-butyl acetoacetate. Examples of the β-diketone compounds include acetylacetone, hexane-2,4-dione, heptane-2,4-dione, heptane-3,5-dione, octane-2,4-dione, nonane-2,4-dione, and 5-methyl-hexane-2,4-dione. These compounds may be used alone or in combination.

[0028] Commercially available organic zinc catalysts are not particularly limited, and examples thereof include K-KAT 670 and K-KAT XK-648 manufactured by KING INDUSTRIES, and Borchikat 0244, Borchika 15, and Borchika 22 manufactured by OMG Borchers GmbH, but are not limited thereto.

[0029] The blending amount of component (C) is in the range of 0.01 to 25 parts by mass, more preferably 0.01 to 20 parts by mass, and particularly preferably 0.01 to 10 parts by mass, per 100 parts by mass of component (A). By being in the above range, the moisture-curable resin composition has excellent sealing properties.

[0030] Furthermore, the moisture-curable resin composition of the present invention may further contain a plasticizer as component (D), provided that the object of the present invention is not impaired. Component (D) can be broadly classified into phthalate ester plasticizers and non-phthalate plasticizers. Non-phthalate ester plasticizers are preferred because they are less carcinogenic and can maintain the effects of the present invention. Non-phthalate plasticizers are not particularly limited, but examples include (meth)acrylic polymer plasticizers obtained by polymerizing (meth)acrylic monomers; polyether polyol plasticizers such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol; polyester plasticizers obtained from dibasic acids such as sebacic acid and adipic acid and dihydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, and propylene glycol; process oil plasticizers; alkylsulfonic acid phenyl esters; and acetyl tributyl citrate.

[0031] Commercially available non-phthalate plasticizers include Adeka Cizer PN-7160, PN-160, and PN-9302, which are polyester plasticizers derived from adipic acid; Mezamol (registered trademark) manufactured by LANXESS, which is an alkylsulfonic acid phenyl ester; and Adeka Cizer PN-6810, which is acetyl tributyl citrate.

[0032] The amount of component (D) added is preferably within a range from 5 to 300 parts by mass, more preferably from 10 to 150 parts by mass, even more preferably from 12 to 75 parts by mass, particularly preferably from 15 to 70 parts by mass, and most preferably from 20 to 60 parts by mass, per 100 parts by mass of component (A) of the present invention. By keeping the amount within the above range, even better sealing properties are achieved.

[0033] Furthermore, the moisture-curable resin composition of the present invention may contain a silane compound having an alkoxysilyl group as component (E), provided that the object of the present invention is not impaired. The silane compound having an alkoxysilyl group refers to a silane compound, excluding component (A), particularly a compound having a molecular weight of 1,000 or less. Examples of component (E) include (E1) a silane compound having a reactive functional group other than an alkoxysilyl group, and (E2) a silane compound having no reactive functional group other than an alkoxysilyl group. (E1) can act as an adhesion promoter to improve adhesion, while (E2) can act as a storage stabilizer. Examples of reactive functional groups other than alkoxysilyl groups include, but are not limited to, vinyl groups, epoxy groups, (meth)acrylic groups, amino groups, isocyanurate groups, ureido groups, mercapto groups, isocyanate groups, acid anhydride groups, and carboxy groups.

[0034] Specific examples of (E1) include silane compounds having a vinyl group, such as vinyltrimethoxysilane and vinyltriethoxysilane; and amino groups, such as N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane. silane compounds having an epoxy group such as 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-glycidoxysilyltriethoxysilane; and silane compounds having a (meth)acrylic group such as 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, and 3-(meth)acryloxypropyltriethoxysilane. Among these, it is preferable to include a silane compound having an amino group as (E1) from the viewpoint of adhesive strength, and N-2-(aminoethyl)-3-aminopropyltrimethoxysilane is more preferable. The amount of (E1) added is in the range of 0.05 to 10 parts by mass, more preferably 0.5 to 7 parts by mass, and particularly preferably 1 to 4 parts by mass, per 100 parts by mass of component (A).

[0035] Specific examples of (E2) include silicate compounds such as methyl silicate, ethyl silicate, propyl silicate, and butyl silicate; silane compounds having an alkyl group such as dimethyldimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, and hexyltrimethoxysilane; and silane compounds having a phenyl group such as phenyltrimethoxysilane, diphenyldimethoxysilane, and phenyltriethoxysilane. Among these, a silane compound having an alkyl group is preferred as (E2) from the viewpoint of storage stability, and methyltrimethoxysilane is even more preferred. The amount of (E2) added is in the range of 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, and particularly preferably 3 to 10 parts by mass, per 100 parts by mass of component (A). A content of (E2) in the range of 0.05 to 10 parts by mass improves storage stability and prevents deterioration of curability.

[0036] The moisture-curable resin composition of the present invention may further contain an inorganic filler as component (F), provided that the object of the present invention is not impaired. Component (F) is not particularly limited, but examples include talc powder, silica powder, clay powder, calcium carbonate powder, magnesium carbonate powder, calcium silicate powder, glass powder, alumina powder, zinc oxide powder, magnesium oxide powder, aluminum nitride powder, boron nitride powder, carbon powder, diamond powder, gold powder, silver powder, copper powder, and nickel powder, excluding component (B). Component (F) may also be surface-treated with a fatty acid soap or the like. These may be used alone or in combination.

[0037] To impart a high modulus to the cured product of a moisture-curable resin composition, component (F) is preferably talc powder, silica powder, clay powder, calcium carbonate powder, magnesium carbonate powder, calcium silicate powder, or glass powder, with calcium carbonate powder being particularly preferred. Furthermore, calcium carbonate powder preferably includes one that has been surface-treated with a fatty acid soap or the like. More preferably, surface-treated calcium carbonate powder and untreated calcium carbonate powder are used in combination. Next, to impart thermal conductivity to the moisture-curable resin composition, component (F) is preferably a thermally conductive powder such as alumina powder, zinc oxide powder, magnesium oxide powder, aluminum nitride powder, boron nitride powder, carbon powder, or diamond powder. To impart flame retardancy to the moisture-curable resin composition, component (F) is preferably aluminum hydroxide powder. To impart conductivity to the moisture-curable resin composition, conductive fillers such as gold powder, silver powder, copper powder, or nickel powder are preferred.

[0038] From the viewpoint of obtaining a moisture-curable resin composition having excellent sealing properties, the average particle size (50% average particle size) of the component (F) is preferably 0.001 to 90 μm, more preferably 0.005 to 50 μm, even more preferably 0.01 to 20 μm, particularly preferably 0.01 to 10 μm, and most preferably 0.03 to 5 μm. In the present invention, the average particle size refers to the particle size (volume average) at 50% of the cumulative size in a particle size distribution determined by, for example, a laser diffraction / scattering method (also referred to as D50).

[0039] In one embodiment, when surface-treated calcium carbonate and non-surface-treated calcium carbonate are used in combination as component (F), the average particle size of each calcium carbonate is different, thereby improving adhesion to aluminum. For example, the average particle size of the surface-treated calcium carbonate is preferably 0.001 to 10 μm, more preferably 0.005 to 5 μm, even more preferably 0.01 to 1 μm, particularly preferably 0.01 to 0.5 μm, and most preferably 0.01 to 0.3 μm. For example, the average particle size of the non-surface-treated calcium carbonate is preferably 0.01 to 90 μm, more preferably 0.05 to 50 μm, even more preferably 0.1 to 20 μm, particularly preferably 0.5 to 10 μm, and most preferably 0.7 to 5 μm.

[0040] The amount of component (F) blended is preferably in the range of 2 to 400 parts by mass, more preferably 10 to 300 parts by mass, even more preferably 30 to 200 parts by mass, particularly preferably 50 to 180 parts by mass, and most preferably 100 to 170 parts by mass, per 100 parts by mass of component (A). By being within the above range, adhesion to aluminum is further improved. When two or more types of component (F) are used in combination, the above blending amount is the combined amount.

[0041] In one embodiment, when surface-treated calcium carbonate and non-surface-treated calcium carbonate are used in combination as component (F), the mass ratio of the surface-treated calcium carbonate to the non-surface-treated calcium carbonate (surface-treated calcium carbonate:(non-surface-treated calcium carbonate) is preferably 10:1 to 1:10, more preferably 5:1 to 1:5, and even more preferably 3:1 to 1:3. By using surface-treated calcium carbonate and non-surface-treated calcium carbonate in the above mass ratio in combination as component (F), it is possible to achieve even better adhesiveness.

[0042] The moisture-curable resin composition of the present invention may further contain an aromatic secondary amine compound as component (G) within the scope of the present invention, excluding the component (E). The addition of component (G) has the effect of improving heat resistance. Specific examples of component (G) include phenylenediamine compounds and diphenylamine compounds, with phenylenediamine compounds being most preferred from the viewpoint of not impairing sealing properties. A single compound may be used, or two or more compounds may be used in combination.

[0043] Specific examples of the phenylenediamine compounds include N,N'-di-2-naphthyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylenediamine, N-phenyl-N'-(3-methacryloyloxy-2-hydroxypropyl)-p-phenylenediamine, 4-(anilinophenyl)methacrylamide, 2-[(mercaptoacetyl)oxy]ethyl-3-[[4-(phenylamino)phenyl]amino]butanate, N,N'-bis(1- Examples of the diamine include, but are not limited to, N,N-bis(1,4-dimethylpentyl)-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, N-cyclohexyl-N'-phenyl-p-phenylenediamine, 2,4,6-tris(N-1,4-dimethylpentyl-p-phenylenediamino)1,3,5-triazine, diallyl-p-phenylenediamine mixture, and phenyl-octyl-p-phenylenediamine. From the viewpoint of excellent heat resistance, N,N'-di-2-naphthyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamine, N-isopropyl-N'-phenylene-p-phenylenediamine, and N-phenyl-N'-(3-methacryloyloxy-2-hydroxypropyl)-p-phenylenediamine are preferred, and N,N'-di-2-naphthyl-p-phenylenediamine is particularly preferred.

[0044] Specific examples of the diphenylamine compounds include, but are not limited to, 4,4'-bis(α,α-dimethylbenzyl)diphenylamine, p-(p-toluenesulfonylamido)diphenylamine, 4,4'-distyryldiphenylamine, 4,4'-dioctyldiphenylamine, octylated diphenylamine, bis(phenyl-isopropylidene)-4,4-diphenylamine, 4-(α-phenylethyl)diphenylamine, 4,4'-bis(α-phenylethyl)diphenylamine, and di-tert-butyldiphenylamine. From the viewpoint of not interfering with sealing properties, 4,4'-bis(α,α-dimethylbenzyl)diphenylamine, p-(p-toluenesulfonylamido)diphenylamine, 4,4'-distyryldiphenylamine, 4,4'-dioctyldiphenylamine, octylated diphenylamine, or bis(phenyl-isopropylidene)-4,4-diphenylamine is preferred, and 4,4'-bis(α,α-dimethylbenzyl)diphenylamine is particularly preferred.

[0045] Examples of commercially available products of component (G) include, but are not limited to, the Nocrac series manufactured by Ouchi Shinko Chemical Industry Co., Ltd., such as PA, ODA, ODA-N, AD-F, CD, TD, White, 810-NA, 6C, and G-1, and products manufactured by Seiko Chemical Co., Ltd., such as Nonflex OD-3, Nonflex DCD, and Steerer LAS.

[0046] The amount of (G) added is preferably 0.01 to 20 parts by mass, and more preferably 0.5 to 5.0 parts by mass, per 100 parts by mass of component (A).Within this range, there is no risk of impairing sealing properties.

[0047] Additives such as curing accelerators, thioether antioxidants, solvents, light stabilizers, heavy metal deactivators, tackifiers, antifoaming agents, dyes, pigments, rust inhibitors, leveling agents, dispersants, rheology modifiers, and surfactants may also be used in the present invention, provided that the purpose of the present invention is not impaired.

[0048] The curing accelerator may be an amine compound. Specific examples include primary amines, secondary amines, and tertiary amines. However, the above-mentioned components (E) and (G) are excluded. Examples of the primary amine include N-propylamine, N-isopropylamine, N-butylamine, N-benzylamine, N-hexylamine, N-cyclohexylamine, Nn-octylamine, N-(2-ethylhexyl)amine, N-(2-phenylethyl)amine, N-(3-methoxypropyl)amine, N-decylamine, N-dodecylamine, and ethylenediamine. Examples of the secondary amines include N,N-dipropylamine, N,N-diisopropylamine, N,N-dibutylamine, N,N-dihexylamine, N,N-dicyclohexylamine, N,N-bis(2-methoxyethyl)amine, N,N-dioctylamine, N,N-bis(2-ethylhexyl)amine, N,N-diisononylamine, N,N-bis(tridecyl)amine, morpholine, 2,2,6,6-tetramethylpiperidine, N,N'-dimethylethylenediamine, N,N'-diethylethylenediamine, and N,N'-diisopropylethylenediamine. Examples of the tertiary amines include 3-diethylaminopropylamine, imidazole, 1-methylimidazole, 1-butylimidazole, 1,2-dimethylimidazole, tetramethylguanidine, DBU, and DBN.

[0049] The present invention can include the thioether-based antioxidant. Examples of thioether-based antioxidants include pentaerythritol tetrakis[3-(dodecylthio)propionate], pentaerythrityl tetrakis(3-laurylthiopropionate), dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, and distearyl-3,3'-thiodipropionate. One or more types of thioether-based antioxidants may be used. Commercially available thioether-based antioxidants include Adeka STAB AO-503, AO-26, and AO-412S (manufactured by ADEKA Corporation).

[0050] The present invention can include the above-mentioned solvents. Specific examples of the solvent include ketone-based solvents, alcohol-based solvents, glycol-based solvents, hydrocarbon-based solvents, and ester-based solvents.

[0051] <Curing method and cured product> The present invention can be made into a one-component or two-component composition. Here, the term "two-component" refers to a form in which the composition is cured by mixing two components when used. When the moisture-curable resin composition of the present invention is made into a two-component composition, the storage stability can be improved by separating the components (B) and (C) into two components, and it does not matter whether the component (A) is contained in either component. The moisture-curable resin composition of the present invention can be cured by the humidity and temperature of the ambient air. Furthermore, curing can be accelerated using a hot air drying oven or the like as long as the temperature is below the thermal expansion temperature of the component (B). Specific curing conditions are, for example, a temperature range of 5 to 50°C, a humidity range of 40 to 70% RH, and a curing time of 5 minutes to 10 days. Furthermore, a cured product obtained by curing the moisture-curable resin composition of the present invention also constitutes one aspect of the present invention.

[0052] <Application> Since the cured product of the present invention has excellent sealing properties and dismantling properties, it is preferably used in various applications such as adhesives, sealing agents, potting agents, coating agents, thermally conductive resins, flame-retardant resins, and conductive pastes, and is particularly used in applications such as automobile parts, electrical and electronic parts, and building materials.

[0053] Examples of the automobile parts include 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, in-vehicle electronic boards, nickel batteries, Li batteries, and fuel cells. In particular, the automobile parts are suitable for use as reusable components because they can be easily disassembled.

[0054] Furthermore, when thermal conductivity is imparted to the present invention, it can be used in a variety of applications, such as heat dissipation from electronic substrates, heat dissipation from electronic devices such as mobile phones and personal computers, heat dissipation from lighting such as LEDs, heat dissipation from optical pickup modules, heat dissipation from camera modules, heat dissipation from sensing devices, heat dissipation from power semiconductors, heat dissipation from inverters, heat dissipation from converters, and heat dissipation from ECU components.

[0055] The present invention can be adhered to various adherends. In particular, because of its excellent adhesion to aluminum, it is suitable for use as an adhesive or sealant in applications where aluminum is used. Examples of applications where aluminum is used include backsheets containing an aluminum layer used in solar cells, heat dissipation fins, battery cases, etc.

[0056] <How to use> Sealing techniques using the present invention are not particularly limited, but a representative example is FIPG (formed-in-place gasketing). FIPG is a technique in which the present invention is applied to a flange of a sealed part using an automatic application device or the like, and then the flange is bonded to another flange, and the moisture-curable resin composition is cured to form an adhesive seal. 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, the method comprising the steps of: applying the moisture-curable resin composition described above to the surface of at least one of the 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 moisture-curable resin composition to seal at least a portion of the gap between the at least two flanges.

[0057] <Disassembly method> The cured product of the moisture-curable resin composition of the present invention can be disassembled from the adherend by heating. For example, the entire adherend, including the cured product, can be heated using a temperature-controllable hot air drying oven, or a heat gun capable of heating only a portion of the adherend can be used. The disassembly temperature applied to the cured product during disassembly is preferably 70 to 400°C, particularly preferably 100 to 350°C, and most preferably 110 to 300°C. The disassembly time is preferably 1 to 600 seconds, particularly preferably 5 to 300 seconds, and most preferably 10 to 100 seconds. The component (B) begins to expand at the expansion initiation temperature, continues to expand as the temperature increases, and stops expanding once the temperature reaches a certain level. Therefore, the higher the temperature applied to the cured product, the easier it is to disassemble the adherends. In practice, it is difficult to precisely control the temperature of the cured product of the present invention before disassembly, i.e., the temperature of the cured product present in the narrow gaps between the adherends, just before the adherends are disassembled. Therefore, a realistic heating condition is to gradually heat from room temperature to the above-mentioned expansion starting temperature range or higher, whereby the thermally expandable particles expand as the temperature rises, and the adherends are disassembled. Furthermore, the cured product can be easily disassembled by applying force to it after thermal expansion. The force applied during disassembly is, for example, 400 g / cm. 2 Less than 100 g / cm is preferred 2 More preferably, 40 g / cm 2 The following is most preferred. The disintegration state of the cured product will be either interfacial failure or cohesive failure, depending on the content of thermally expandable particles, the adhesive strength between the adherend and the cured product, and the thermal conductivity of the adherend. Specifically, due to reasons such as the high thermal conductivity of the adherend, particles expand near the interface of the adherend upon heating, creating voids between the cured product and the adherend, resulting in interfacial failure. Furthermore, uniform thermal expansion of the entire cured product will make the cured product itself brittle, resulting in failure with the cured product remaining on the surface of the adherend, i.e., cohesive failure. Considering the possibility of reusing the adherend, it may be possible to perform a process such as scraping off the cured product after thermal expansion from the adherend. [Example]

[0058] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Hereinafter, the resin composition may be simply referred to as the composition.

[0059] The following raw materials were used to prepare Examples 1 to 6 and Comparative Example 1. Component (A): an organic polymer having two or more alkoxysilyl groups in the molecule a1: A linear polyoxyalkylene having trimethoxysilyl groups at both ends and a viscosity of 50 Pa·s at 25°C (Silyl SAX575, manufactured by Kaneka Corporation) Component (B): Thermally expandable particles b1: Microcapsules with a shell made of acrylic polymer and an expansion component made of isopentane (expansion starting temperature 123-133°C, particle size before expansion (D50) 12 μm, (D10) 7.3 μm, (D90) 19 μm, manufactured by Nippon Phillite Co., Ltd., Expancel920DU40) b2: Microcapsules with a shell made of acrylic polymer and an expansion component made of isopentane (expansion starting temperature 120-130°C, particle size before expansion (D50) 21 μm, (D10) 12 μm, (D90) 34 μm, manufactured by Nippon Phillite Co., Ltd., Expancel909DU80) b3: Microcapsules with a shell made of acrylic polymer and an expansion component made of isobutane (expansion starting temperature 122-132°C, particle size before expansion (D50) 35 μm, (D10) 19 μm, (D90) 58 μm, manufactured by Nippon Phillite Co., Ltd., Expancel930DU120) b4: Microcapsules with a shell made of acrylic polymer and an expansion component made of isopentane (expansion starting temperature 160-170°C, particle size before expansion (D50) 35 μm, (D10) 7.5 μm, (D90) 45 μm, Matsumoto Yushi Pharmaceutical Co., Ltd. Matsumoto Microsphere F-190D) (C) Component: Organometallic catalyst c1: Organozinc catalyst containing alkylamine (KING INDUSTRIES K-KAT670) (D) Component: Plasticizer d1: Alkyl sulfonic acid phenyl ester (Mezamol, manufactured by Lanxess KK) Component (E1): a silane compound having a reactive group other than an alkoxysilyl group e1: N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.) Component (E2): a silane compound having no reactive groups other than alkoxysilyl groups e2: Methyltrimethoxysilane (KBM-13, manufactured by Shin-Etsu Chemical Co., Ltd.) (F) Ingredient: inorganic filler f1: Calcium carbonate treated with fatty acid soap (average particle size 0.05 μm, manufactured by Maruo Calcium Co., Ltd., Calfine 500) f2: Untreated calcium carbonate (average particle size 1.3 μm, Softon 1800 manufactured by Bihoku Funka Kogyo Co., Ltd.) (G) Component: Aromatic secondary amine compound g1: N,N'-di-2-naphthyl-p-phenylenediamine (Nocrac White, manufactured by Ouchi Shinko Chemical Industry Co., Ltd.)

[0060] Components (A), (B), (F), and (G) were weighed into a stirring vessel and stirred at 80°C for 90 minutes with a stirrer while vacuum degassing. After cooling with a chiller until the liquid temperature reached 40°C or below, component (D) was weighed and stirred for 30 minutes in a 25°C atmosphere while vacuum degassing. Next, components (C) and (E) were stirred for 10 minutes in a 25°C atmosphere. Note that detailed amounts prepared are shown in Table 1, and all values ​​are expressed in parts by mass.

[0061] The test methods used in the examples and comparative examples in Table 1 are as follows. [Tensile shear adhesive strength test] Using aluminum (A1050P) test pieces measuring 25 mm wide, 100 mm long, and 1 mm thick, two test pieces were bonded together with a composition over a 10 mm x 25 mm adhesive area (1 mm clearance), and then left to cure for 7 days in an atmosphere of 23°C and 50% RH 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 the tensile shear adhesive strength (MPa). Considering sealing properties, the tensile shear adhesive strength is preferably 1.0 MPa or more. The peeling condition was also visually confirmed. To maintain sealing properties for a long time, it is preferable that the disassembly condition be "○". <Evaluation criteria> ○: 80% to 100% of the demolished surface is cohesive failure. ×: Cohesive failure occurs on 0% or more but less than 80% of the demolished surface.

[0062] [Initial pressure resistance test] The compositions listed in Table 1 were applied to a pressure-resistant flange made of JIS G 3101 SS400 material with a flange width of 10 mm and a flange frame size (inside) of 60 mm across the entire flange width using a dispenser. A spacer was installed to maintain the thickness of the applied composition at 500 μm, and the flanges were then assembled with bolts. Ninety minutes after assembly, pressurized air was pumped into the flange using a pressure pump, and the presence or absence of air leakage was confirmed. The pressure at which air began to leak was recorded as the "initial pressure resistance (MPa)." All of the assembled flanges were blind flanges, with one end equipped with a nozzle capable of introducing pressurized air into the flange. Considering sealing performance, the initial pressure resistance is preferably 0.03 MPa or greater.

[0063] [Dismantling test] Using steel (SPCC-SD) test pieces measuring 25 mm wide x 100 mm long x 1.6 mm thick, two test pieces were bonded together with a composition over a 10 mm x 25 mm adhesive area (1 mm clearance). The test pieces were then left at 23°C and 50% RH for 7 days to cure the composition and produce test pieces. Next, the upper end of the test piece was fixed, and a 100 g weight was attached to the lower end. A heat gun was then applied to one side of the adhesive surface of the test piece, and the time until the test piece fell off was recorded as "dismantleability (seconds)." The test was performed with a distance of approximately 1 cm between the overlapping surface of the test piece and the heat gun nozzle. The temperature measured with a thermocouple approximately 1 cm from the heat gun nozzle was 230°C. Dismantleability was preferably achieved within 100 seconds, and more preferably within 70 seconds. If the test piece did not fall off after 300 seconds, it was recorded as "-" in Table 1.

[0064] [Table 1]

[0065] Furthermore, the temperature-dependent expansion coefficients of Examples 4 and 6 were examined. The compositions were cured by leaving them in an atmosphere of 23°C and 50% RH for 7 days, and then cut into test pieces measuring 10 mm wide x 60 mm long x 2 mm thick. The cured products were heated in a thermostatic chamber from 90 to 190°C in 10°C increments for 1 hour. Dimensions were measured with calipers, and the expansion coefficient (%) was calculated as (width direction after heating, mm) x (length direction after heating, mm) / (10 mm x 60 mm) x 100. At 160°C, Example 4 expanded 259% and Example 6 expanded 165%. At 180°C, Example 4 expanded 341% and Example 6 expanded 214%. At 190°C, Example 4 expanded 270% and Example 6 expanded 151%. The decrease in expansion coefficient at 190°C is due to the cracking of the thermally expandable particles, resulting in gas release and shrinkage.

[0066] According to Table 1, Comparative Example 1 does not contain component (B), and therefore does not have dismantling properties. On the other hand, Examples 1 to 6 are moisture-curable resin compositions that have adhesive and sealing properties and can be easily dismantled at any time. Examples 1 to 4 differ in particle size and expansion start temperature of component (B), but are also dismantling properties. Example 5 has an extremely small amount of component (B), which results in poor dismantling properties, but the tensile shear bond strength is high. Example 6 reduces the amount of component (B) to half that of Examples 1 to 4, but it is clear that this does not have a significant effect on adhesive properties, sealing properties, or dismantling properties. [Industrial Applicability]

[0067] The moisture-curable resin composition of the present invention has excellent dismantling properties and is therefore industrially useful since it can be applied in a wide range of fields, such as in equipment and machinery that require part replacement.

Claims

1. A moisture-curable resin composition comprising the following components (A) to (C): Component (A): an organic polymer having two or more alkoxysilyl groups Component (B): thermally expandable particles (C) Component: Organometallic catalyst

2. 2. The moisture-curable resin composition according to claim 1, wherein the component (B) is a microcapsule-type heat-expandable particle.

3. The moisture-curable resin composition according to claim 1 or 2, comprising 10 parts by mass or more and 200 parts by mass or less of the component (B) per 100 parts by mass of the component (A).

4. 3. The moisture-curable resin composition according to claim 1, wherein the component (C) is an organic zinc catalyst.

5. The moisture-curable resin composition according to claim 1 or 2, further comprising a plasticizer as component (D).

6. The moisture-curable resin composition according to claim 1 or 2, further comprising a silane compound having an alkoxysilyl group (excluding the component (A)) as a component (E).

7. The moisture-curable resin composition according to claim 1 or 2, further comprising an inorganic filler as the component (F).

8. 3. The moisture-curable resin composition according to claim 1, comprising 50 to 200 parts by mass of the component (F) per 100 parts by mass of the component (A).

9. A sealant or adhesive comprising the moisture-curable resin composition having thermal dismantling properties according to claim 1 or 2.

10. A cured product obtained by applying the moisture-curable resin composition having thermal dismantling properties according to claim 1 or 2 to an adherend and curing the composition.

11. A disassembly method for disassembling the cured product according to claim 10 from an adherend by heating.

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