Curable composition and cured product

Abstract

To provide a curable composition that has high storage stability.SOLUTION: A curable composition according to one embodiment of the present invention comprises component A: a (meth)acrylic block copolymer having a silyl group, component B: a (meth)acrylic random copolymer having a silyl group, component C: a polyvalent amine, and component D: a curing catalyst. The component A and the component B are copolymers that satisfy specific conditions.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a curable composition and a cured product.

Background Art

[0002] Polymer molecules having silyl groups form siloxane bonds with other polymer molecules by hydrolysis of the silyl groups. A rubbery cured product is obtained by this cross-linking reaction. Curable compositions containing such polymer molecules are used in sealing materials, adhesives, paints, etc. (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The curable compositions disclosed in the prior art such as Patent Document 1 had room for improvement in storage stability.

[0005] One aspect of the present invention aims to provide a curable composition having high storage stability.

Means for Solving the Problems

[0006] In order to solve the above problems, a curable composition according to one aspect of the present invention contains the following components A to D: Component A: A (meth)acrylic block copolymer having a silyl group; Component B: A (meth)acrylic random copolymer having a silyl group; Component C: A polyvalent amine; Component D: A curing catalyst; Here, the above Component A is It has an XY diblock structure or an XYX triblock structure having an X block and a Y block in the molecule, The repeating unit derived from the silyl group-containing (meth)acrylate monomer contained in the X block is more than 2.0 on average, The repeating unit derived from the silyl group-containing (meth)acrylate monomer contained in the Y block is 0% by weight or more and less than 5% by weight based on the weight of all the repeating units contained in the Y block, The molecular weight distribution (Mw / Mn) is 1.8 or less; Here, the component B has an average of 1.0 or more silyl groups per molecule derived from the silyl group-containing (meth)acrylate monomer, The molecular weight distribution (Mw / Mn) is more than 1.8.

Advantages of the Invention

[0007] According to one aspect of the present invention, a curable composition with high storage stability is provided.

Modes for Carrying Out the Invention

[0008] Hereinafter, an example of an embodiment of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and various modifications may be made within the scope shown in the claims. Embodiments in which technical means described in different embodiments are combined are also included in the technical scope of the present invention.

[0009] Unless otherwise specified in this specification, "A~B" representing a numerical range means "A or more and B or less". In this specification, "(meth)acryl" means "acryl and / or methacryl". Unless otherwise specified in this specification, "silyl group" means "hydrolyzable silyl group". In one embodiment, the silyl group is an alkoxysilyl group.

[0010] 〔1. Components of the curable composition〕 The curable composition according to one aspect of the present invention contains Component A: a (meth)acrylic block copolymer having a silyl group, Component B: a (meth)acrylic random copolymer having a silyl group, Component C: a polyvalent amine, and Component D: a curing catalyst. The curable composition may contain, as an optional component, Component E: a polyoxyalkylene polymer having a silyl group. The curable composition may contain other components. Each of these components may contain only one type or may contain two or more types.

[0011] [1.1. Component A: (meth)acrylic block copolymer having a silyl group] Component A is a (meth)acrylic block copolymer having a silyl group. Component A has a silyl group derived from a silyl group-containing (meth)acrylic acid ester monomer. Component A has an X block with a high frequency of silyl group appearance and a Y block with a low frequency of silyl group appearance. Component A can be polymerized, for example, by changing the monomer composition during polymerization.

[0012] [1.1.1. Structure of Component A] Component A has an X block and a Y block and contains an XY diblock structure or an XYX triblock structure in the molecule. Note that the overall structure of Component A is not particularly limited as long as it contains an XY diblock structure or an XYX triblock structure, and may be, for example, an XYXY tetrablock structure.

[0013] Here, the "XYX triblock structure" means the "ABA triblock structure" generally referred to among those skilled in the art. The ratio of X / Y in Component A is preferably (5 / 95) to (60 / 40), and more preferably (15 / 85) to (40 / 60).

[0014] In one embodiment, the molecule of component A has an XY diblock structure. In the molecule with an XY diblock structure, the X block can be a region of 40% or less, 30% or less, or 25% or less from one end of the molecule (assuming the total repeating units contained in the molecule is 100%). Here, the X block is the block where silyl groups are relatively more distributed.

[0015] In one embodiment, the molecule of component A has an XYX triblock structure. In the molecule with an XYX triblock structure, the X block can be a region of 40% or less, 30% or less, or 25% or less from the ends of the molecule (assuming the total repeating units contained in the molecule is 100%). Here, the X blocks are located at both ends of the molecule.

[0016] Component A has repeating units derived from a silyl group-containing (meth)acrylate monomer. The repeating units derived from the silyl group-containing (meth)acrylate monomer are relatively more contained in the X block. The average number of repeating units derived from the silyl group-containing (meth)acrylate monomer contained in the X block is more than 2.0. When component A has two or more X blocks in one molecule, the total number of repeating units derived from the silyl group-containing (meth)acrylate monomer contained in the plurality of X blocks is more than 2.0 on average. On the other hand, the repeating units derived from the silyl group-containing (meth)acrylate monomer contained in the Y block are 0 wt% or more and less than 5 wt% based on the weight of all the repeating units contained in the Y block.

[0017] The number of repeating units derived from the silyl group-containing (meth)acrylate monomer contained in the X block is more than 2.0 on average, preferably 2.1 or more, more preferably 2.2 or more, still more preferably 2.3 or more, and particularly preferably 2.5 or more. Similarly, the repeating units derived from the silyl group-containing (meth)acrylate monomer contained in the X block are preferably 0.5% by weight or more, more preferably 2.0% by weight or more, and still more preferably 3.0% by weight or more based on the weight of all the repeating units contained in the X block. The upper limit of the repeating units derived from the silyl group-containing (meth)acrylate monomer contained in the X block is preferably 90% by weight or less, more preferably 60% by weight or less, and still more preferably 30% by weight or less.

[0018] The upper limit of the repeating units derived from the silyl group-containing (meth)acrylate monomer contained in the Y block is less than 5% by weight, preferably 4% by weight or less, more preferably 3% by weight or less, still more preferably 2% by weight or less, and particularly preferably 1% by weight or less based on the weight of all the repeating units contained in the Y block. The lower limit of the repeating units derived from the silyl group-containing (meth)acrylate monomer contained in the Y block is preferably 0% by weight or more, and more preferably more than 0% by weight based on the weight of all the repeating units contained in the Y block.

[0019] The number of silyl groups introduced into Component A is more than 2.0 on average, preferably 2.2 or more, more preferably 2.6 or more, still more preferably 3.0 or more, and particularly preferably 3.4 or more as a whole molecule. The upper limit of the number of silyl groups introduced into the (meth)acrylic polymer is preferably 10.0 or less, more preferably 8.0 or less, still more preferably 6.0 or less, and particularly preferably 5.0 or less. When the number of silyl groups is within the above range, a curable composition and a cured product with good physical properties can be obtained.

[0020] Specific examples of the silyl group-containing (meth)acrylic acid ester monomer include 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, and 3-acryloxypropyltrimethoxysilane.

[0021] Component A may contain a repeating unit derived from a (meth)acrylic monomer having a long side chain. As used herein, the "(meth)acrylic monomer having a long side chain" refers to a monomer represented by the formula: CH2=C(R 1 )COOR 2 . In the formula, R 1 is a hydrogen atom or a methyl group. R 2 is a group having 9 or more carbon atoms.

[0022] The content of the repeating unit derived from the (meth)acrylic monomer having a long side chain is preferably 1% by weight or more based on all the constituent units contained in Component A. Component A containing such a repeating unit may have improved compatibility with a polyoxyalkylene polymer or improved physical properties of the resulting cured product. The upper limit of the content of the repeating unit derived from the (meth)acrylic monomer having a long side chain is preferably 5% by weight or less, more preferably 3% by weight or less. If the content is within the above range, the production cost of Component A can be kept from rising extremely.

[0023] Examples of the (meth)acrylic monomer having a long side chain include nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, icosyl (meth)acrylate, docosyl (meth)acrylate, oleyl (meth)acrylate, linoleyl (meth)acrylate, and isobornyl (meth)acrylate.

[0024] Among the above-mentioned monomers, one or more selected from octadecyl (meth)acrylate, oleyl (meth)acrylate, and linoleyl (meth)acrylate are preferable. These monomers are liquid at room temperature and have the advantage of high polymerization stability. Further, by blending these monomers, a (meth)acrylic acid polymer having high compatibility with the polyoxyalkylene polymer can be obtained.

[0025] In the present specification, the "(meth)acrylic monomer having a non-long-chain side chain" means, in the above formula, a monomer in which R 2 is a group having 8 or less carbon atoms. Examples of such monomers include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, isopropoxyethyl (meth)acrylate, benzyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, glycidyl (meth)acrylate, 1-ethylcyclopentyl ether (meth)acrylate, and dimethylaminoethyl (meth)acrylate.

[0026] Among the above-mentioned monomers, one or more selected from methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate are preferable. These monomers have low procurement costs and are suitable for the purpose of reducing the manufacturing cost of Component A.

[0027] Furthermore, from the perspective of the glass transition point, one or more selected from n-butyl acrylate and 2-ethylhexyl acrylate are preferred. Component A obtained from these monomers has a low glass transition point, and the viscosity of the polymer becomes low. Therefore, a curable composition that is easy to use in a low-temperature environment can be obtained.

[0028] Component A may have a repeating unit derived from a monomer other than the (meth)acrylate monomer. In component A, the proportion of the repeating unit derived from the (meth)acrylate monomer is preferably 50% by weight or more, more preferably 70% by weight or more, and even more preferably 90% by weight or more of the total weight of component A.

[0029] [1.1.2. Silyl group possessed by component A] The silyl group possessed by component A may be derived from a silyl group-containing (meth)acrylate monomer. In one embodiment, the silyl group is represented by the following general formula (1). -[Si(R 3 ) 2-b (Y) b O] m -Si(R 4 ) 3-a (Y) a (1)

[0030] In formula (1), R 3 and R 4 are independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, a methoxymethyl group, or a triorganosiloxy group represented by (R’)3SiO-. R’ is a monovalent hydrocarbon group having 1 to 20 carbon atoms. The three R’s present may be the same or different. R 3 or R 4When there are two or more of them, they may be the same or different. Y represents a hydroxyl group or a hydrolyzable group. Examples of the hydrolyzable group include an alkoxy group, an acetoxy group, and an oxime group. In one embodiment, Y is a hydroxyl group, a methoxy group, an ethoxy group, or an isopropoxy group. When a plurality of X are contained in one silyl group, they may be the same or different. When a plurality of silyl groups are contained in one molecule of component A, Y may be different for each silyl group. a is 0, 1, 2, or 3. b is 0, 1, or 2. m is an integer from 0 to 19. However, the relationship a + mb ≥ 1 is satisfied.

[0031] The specific structure of the silyl group-containing (meth)acrylic acid ester monomer is not particularly limited. As an example, a monomer represented by the following general formula can be mentioned. H2C=C(R 5 )C(=O)-O-(CH2) m -SiR 6 n (OR 7 ) 3-n

[0032] In the formula, R 5 is hydrogen or a methyl group. R 6 and R 7 are one or more selected from the group consisting of hydrogen, a methyl group, and an ethyl group. When there are a plurality of R 6 and / or R 7 , they may be the same or different. m is an integer from 0 to 10. n is an integer from 0 to 2.

[0033] Specific examples of the silyl group-containing (meth)acrylic acid ester monomer include 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, and 3-acryloxypropyltrimethoxysilane.

[0034] [1.1.3. Physical properties of component A] In one embodiment, the lower limit of the number average molecular weight of component A is preferably 2,000 or more, more preferably 10,000 or more, and even more preferably 15,000 or more. The upper limit of the number average molecular weight of component A is preferably 50,000 or less, more preferably 30,000 or less, and even more preferably 20,000 or less. If the number average molecular weight of component A is within the above range, the viscosity of the curable composition will not become too high, and sufficient workability can be ensured.

[0035] In one embodiment, the molecular weight distribution of component A is 1.8 or less, preferably 1.5 or less, 1.4 or less, 1.3 or less, or 1.2 or less. If the molecular weight distribution is within the above range, the viscosity of the polymer tends to decrease and the workability tends to improve. The molecular weight distribution is a value given by "weight average molecular weight ÷ number average molecular weight".

[0036] The weight average molecular weight and the number average molecular weight are measured by gel permeation chromatography (GPC). For GPC measurement, chloroform is used as the mobile phase and a polystyrene gel column is used as the stationary phase. The molecular weight obtained by the measurement is the molecular weight in terms of standard polystyrene.

[0037] [1.1.4. Method for Producing Component A] The polymerization method of component A is not particularly limited, and known polymerization methods can be used (radical polymerization method, cationic polymerization method, anionic polymerization method, etc.). The polymerization method called SGO (Solid Grade Oligomer; high-temperature continuous bulk polymerization) is preferred because component A can be obtained with little use of a polymerization solvent, a polymerization initiator, a chain transfer agent, etc. The living polymerization method is preferred because a functional group can be introduced near the terminal of the polymer molecule and component A with a small molecular weight distribution can be synthesized. Examples of the living polymerization method include a living radical polymerization method, a living cationic polymerization method, and a living anionic polymerization method. Among them, the living radical polymerization method is suitable for the polymerization of (meth)acrylic monomers. Examples of the living radical polymerization method include the following. · Atom Transfer Radical Polymerization (ATRP) (see J. Am. Chem. Soc. 1995, 117, 5614; Macromolecules. 1995, 28, 1721) · Single Electron Transfer Polymerization (SET-LRP) (see J. Am. Chem. Soc. 2006, 128, 14156; JPSChem 2007, 45, 1607) · Reversible Chain Transfer Catalyzed Polymerization (RTCP) (see "Living Radical Polymerization Controlled by Organocatalysts", Polymer Journal 68, 223 - 231 (2011); JP-A-2014-111798) · Reversible Addition - Fragmentation Chain Transfer Polymerization (RAFT polymerization) · Nitroxide Radical Method (NMP method) · Polymerization Method Using Organotellurium Compounds (TERP method) · Polymerization Method Using Organoantimony Compounds (SBRP method) · Polymerization Method Using Organobismuth Compounds (BIRP method) · Iodine Transfer Polymerization Method

[0038] Examples of methods for introducing a silyl group into Component A include the method described in JP-A-2018-162394. The method disclosed in this document introduces a silyl group into Component A by copolymerizing a (meth)acrylate monomer and a silyl group-containing (meth)acrylate monomer. More specifically, by controlling the input amount of the silyl group-containing (meth)acrylate monomer according to the progress stage of living polymerization, a silyl group is introduced near the terminal of the Component A molecule. Component A obtained by these methods may have a silyl group locally at the terminal or near the terminal of the molecule.

[0039] [1.2. Component B: (Meth)acrylic Random Copolymer Having a Silyl Group] Component B is a (meth)acrylic random copolymer having a silyl group. Component B has a silyl group derived from a silyl group-containing (meth)acrylate monomer. Component B is obtained, for example, by free radical polymerization of monomers. The curable composition containing Component B has improved storage stability.

[0040] [1.2.1. Structure of Component B] Component B has a main chain derived from a (meth)acrylate monomer. This (meth)acrylate monomer includes a silyl group-containing (meth)acrylate monomer. Therefore, Component B has a silyl group derived from a silyl group-containing (meth)acrylate monomer.

[0041] Since Component B is a random copolymer, the insertion positions of the silyl groups are also random. That is, in the polymer molecules constituting Component B, the insertion positions of the silyl groups can be near the ends of the molecular chains or in the central part of the molecular chains. On average, there is no region in Component B where the silyl groups are localized like the X block of Component A.

[0042] Component B may contain a repeating unit derived from a (meth)acrylic monomer having a long side chain. In this specification, the “(meth)acrylic monomer having a long side chain” refers to the formula: CH2=C(R 1 )COOR 2 is a monomer represented by. In the formula, R 1 is a hydrogen atom or a methyl group. R 2 is a group having 9 or more carbon atoms. Examples of such monomers and suitable types of monomers are as described in Section [1.1.1.]. The suitable content of the (meth)acrylic monomer having a long side chain is also as described in Section [1.1.1.].

[0043] In addition, examples and suitable types of (meth)acrylate monomers that can constitute Component B are as described in Section [1.1.1.].

[0044] [1.2.2. Silyl group possessed by Component B] In one embodiment, the silyl group possessed by Component B is represented by the following general formula (2). -W-(CH2) n -Si(R 8 ) 3-a (X) a (2)

[0045] In formula (2), W is a divalent group other than CH2. The number of carbon atoms contained in W is, for example, 1 to 30, 1 to 20, 1 to 10, or 1 to 5.

[0046] In formula (2), n is an integer from 5 to 20. Preferably, n is an integer from 5 to 10. More preferably, n is an integer from 5 to 7.

[0047] In formula (2), R 8 represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. The number of carbon atoms in the hydrocarbon group is preferably 1 to 10, more preferably 1 to 5. R 8 may be substituted with a heteroatom-containing group. Examples of heteroatoms include an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, and a halogen atom (fluorine atom, chlorine atom, bromine atom, and iodine atom). In one embodiment, R 8 is a hydrogen atom, a methyl group, or an ethyl group, preferably a methyl group. When a plurality of R 8 are contained in one silyl group, they may be the same or different. When a plurality of silyl groups are contained in one molecule of Component B, R 8 may be different for each silyl group.

[0048] In formula (2), X represents a hydroxyl group or a hydrolyzable group. Examples of the hydrolyzable group include an alkoxy group, an oxime group, and an acetoxy group. In one embodiment, X is a hydroxyl group, a methoxy group, an ethoxy group, or an isopropoxy group. Preferably, X is a hydroxyl group. When a plurality of X are contained in one silyl group, they may be the same or different. When a plurality of silyl groups are contained in one molecule of component A, X may be different for each silyl group.

[0049] In formula (2), a is 1, 2, or 3.

[0050] The number of silyl groups that component B has is 1.0 or more on average per molecule, preferably 1.5 or more, and more preferably 2.0 or more. The upper limit of the number of silyl groups that component B has can be 5.0 or less, 4.0 or less, 3.0 or less, or 2.0 or less on average per molecule. If the number of silyl groups is within the above range, the silyl groups are sufficiently crosslinked by moisture, and a cured product with sufficient strength can be obtained.

[0051] [Physical properties of 1, 2, and 3. Component B] In one embodiment, the lower limit of the number average molecular weight of component B is preferably 2,000 or more, more preferably 10,000 or more, and even more preferably 15,000 or more. The upper limit of the number average molecular weight of component B is preferably 50,000 or less, more preferably 30,000 or less, and even more preferably 20,000 or less. If the number average molecular weight of component B is within the above range, the viscosity of the curable composition does not become too high, and sufficient workability can be ensured.

[0052] In one embodiment, the molecular weight distribution of component B is more than 1.8, preferably 1.9 or more, and 2.0 or more. The upper limit of the molecular weight distribution of component B can be 4 or less or 3 or less. The molecular weight distribution is a value given by "weight average molecular weight ÷ number average molecular weight".

[0053] In the present invention, when comparing the molecular weight distributions of component A and component B, component A has a smaller value. This is mainly due to the difference in the polymerization method. Component A is generally synthesized by living radical polymerization. Therefore, a polymer product with a relatively narrow molecular weight distribution tends to be obtained. On the other hand, component B is generally synthesized by free radical polymerization. Therefore, a polymer product with a broad molecular weight distribution tends to be obtained.

[0054] The weight average molecular weight and the number average molecular weight are measured by gel permeation chromatography (GPC). For GPC measurement, chloroform is used as the mobile phase and a polystyrene gel column is used as the stationary phase. The molecular weight obtained by the measurement is the molecular weight in terms of standard polystyrene.

[0055] [1.2.4. Method for Producing Component B] The method for producing component B is not particularly limited, and known methods can be mentioned. For example, free radical polymerization can be employed. Specific examples of free radical polymerization include solution polymerization in which a polymerization initiator, a chain transfer agent, a solvent, etc. are added to the polymerization system and polymerized at 50 to 150 °C; continuous bulk polymerization in which an acrylic acid ester monomer is polymerized at high temperature and high pressure (see JP-A-2001-207157), and the like.

[0056] Examples of polymerization initiators include azo compounds (2,2'-azobis(2-methylbutyronitrile), dimethyl 2,2'-azobis(2-methylpropionate), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis[N-(2-propenyl)-2-methylpropionamide], 1,1'-azobis(cyclohexane-1-carbonitrile), etc.); diacyl peroxides (benzoyl peroxide, isobutyryl peroxide, isononanoyl peroxide, decanoyl peroxide, lauroyl peroxide, parachlorobenzoyl peroxide, di(3,5,5-trimethylhexanoyl) peroxide, etc.); peroxydicarbonates (diisopropyl peroxydicarbonate, di-sec-butyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-1-methylheptyl peroxydicarbonate, di-3-methoxybutyl peroxydicarbonate, dicyclohexyl peroxydicarbonate, etc.); peroxy esters (tert-butyl perbenzoate, tert-butyl peracetate, tert-butyl per-2-ethylhexanoate, tert-butyl perisobutyrate, tert-butyl perpivalate, tert-butyl diperadipate, cumyl perneodecanoate, etc.); ketone peroxides (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.); dialkyl peroxides (di-tert-butyl peroxide, dicumyl peroxide, tert-butyl cumyl peroxide, 1,1-di(tert-hexylperoxy)-3,3,5-trimethylcyclohexane, etc.); hydroperoxides (cumene hydroperoxide, tert-butyl hydroperoxide, etc.); and other peroxides (1,1-di(tert-hexylperoxy)-3,3,5-trimethylcyclohexane, etc.). The polymerization initiator may be used alone or in combination of two or more kinds.

[0057] Examples of the chain transfer agent include mercapto group-containing compounds. Examples of the compounds having a mercapto group include n-dodecyl mercaptan, tert-dodecyl mercaptan, and lauryl mercaptan. Further, by using a compound having a mercapto group and a silyl group, a silyl group can be introduced to the molecular chain end of Component B. Examples of such compounds include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, mercaptomethyltrimethoxysilane, and (mercaptomethyl)dimethoxymethylsilane. Only one kind of chain transfer agent may be used, or two or more kinds may be used. The chain transfer agent may have an adverse effect on weather resistance. Therefore, the usage amount of the chain transfer agent is preferably 2% by weight or less of the total amount of the monomers, and it is more preferable not to use it.

[0058] Examples of the solvent include aromatic compounds (such as toluene, xylene, styrene, ethylbenzene, para-dichlorobenzene, di-2-ethylhexyl phthalate, and di-n-butyl phthalate); hydrocarbon compounds (such as hexane, heptane, octane, cyclohexane, and methylcyclohexane); carboxylic acid ester compounds (such as butyl acetate, n-propyl acetate, and isopropyl acetate); ketone compounds (such as methyl isobutyl ketone and methyl ethyl ketone); dialkyl carbonate compounds (such as dimethyl carbonate and diethyl carbonate); and alcohol compounds (such as 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, and amyl alcohol). Among these, one or more selected from dialkyl carbonate compounds and alcohol compounds are preferable. These substances are not the substances for which the Ministry of Health, Labour and Welfare has set guideline values, have little odor, and have a low environmental load. In particular, dimethyl carbonate, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, and tert-butyl alcohol are more preferable, and 2-propanol and isobutyl alcohol are even more preferable. These substances have a high boiling point and can reduce the emission of total volatile organic compounds.

[0059] [1.3. Component C: Polyvalent Amine] Component C is a polyvalent amine. A polyvalent amine is a compound having two or more amino groups or substituted amino groups in total. Examples of Component C include compounds having two amino groups or substituted amino groups (ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, etc.); compounds having three amino groups or substituted amino groups (diethylenetriamine, pentamethyldiethylenetriamine, trimer of ethyleneimine, etc.); compounds having four or more amino groups or substituted amino groups (triethylenetetramine, N,N'-bis(3-aminopropyl)butane-1,4-diamine, tetramer of ethyleneimine, etc.). Component C may be a polymer having a large number of amino groups or substituted amino groups.

[0060] [1.4. Component D: Curing Catalyst] Examples of the curing catalyst include tin-based curing catalysts. Specific examples of the tin-based curing catalysts include dialkyltin carboxylates (dibutyltin dilaurate, dibutyltin diacetate, dibutyltin diethylhexanoate, dibutyltin dioctate, dibutyltin dimethylmaleate, dibutyltin diethylmaleate, dibutyltin dibutylmaleate, dibutyltin diisooctylmaleate, dibutyltin ditridecylmaleate, dibutyltin dibenzylmaleate, dibutyltin maleate, dioctyltin diacetate, dioctyltin distearate, dioctyltin dilaurate, dioctyltin diethylmaleate, dioctyltin diisooctylmaleate, etc.); dialkyltin oxides (dibutyltin oxide, dioctyltin oxide, a mixture of dibutyltin oxide and phthalic acid ester, etc.); reaction products of tetravalent tin compounds (dialkyltin oxide, dialkyltin diacetate, etc.) and silyl group-containing low molecular weight silicon compounds (tetraethoxysilane, methyltriethoxysilane, diphenyldimethoxysilane, phenyltrimethoxysilane, etc.); divalent tin compounds (tin octylate, tin naphthenate, tin stearate, etc.); monoalkyltins (monobutyltin compounds (monobutyltin trisoctoate, monobutyltin triisopropoxide, etc.), monooctyltin compounds, etc.); reaction products or mixtures of amine compounds and organotin compounds (reaction products or mixtures of laurylamine and tin octylate, etc.); chelate compounds (dibutyltin bisacetylacetonate, dioctyltin bisacetylcetonate, dibutyltin bisethylacetonate, dioctyltin bisethylacetonate, etc.); tin alcoholates (dibutyltin dimethylate, dibutyltin diethylate, dioctyltin dimethylate, dioctyltin diethylate, etc.).

[0061] Among these, chelate compounds (such as dibutyltin bisacetylacetonate) and tin alcoholates are preferred in that they have high activity as silanol condensation catalysts. Also, dibutyltin dilaurate is preferred in that it causes little coloring even when added to the curable composition, is inexpensive, and is easily available.

[0062] [1.5. Polyoxyalkylene Polymer Having Silyl Group] [1.5.1. Main chain of Component E] The molecular structure of Component E may be linear or branched. It may also be a mixture of molecules having these structures. Among these, a main chain derived from one or more selected from the group consisting of polyoxypropylene diol and polyoxypropylene triol is particularly preferred.

[0063] Examples of the main chain structure of Component E include structures represented by the following general formula. In the formula, R 6 is a divalent alkylene group. -R 6 -O-

[0064] The structure represented by the above general formula preferably occupies 50% by weight or more, more preferably 70% by weight or more, and even more preferably 90% by weight or more of the total weight of Component E.

[0065] R 6 The structure of is not particularly limited as long as it is a divalent alkylene group. R 6 is preferably an alkylene group having 1 to 14 carbon atoms, and more preferably a linear or branched alkylene group having 2 to 4 carbon atoms.

[0066] Specific examples of the repeating unit represented by the above general formula include -CH2O-, -CH2CH2O-, -CH2CH(CH3)O-, -CH2CH(C2H5)O-, -CH2C(CH3)2O-, -CH2CH2CH2CH2O-. Among these, the main chain of Component E is preferably polypropylene oxide consisting of -CH2CH(CH3)O-.

[0067] [1.5.2. Silyl group possessed by Component E] In one embodiment, the structure of the silyl group contained in Component E is represented by the following general formula (3). -Si(R 9 ) 3-a (X) a (3)

[0068] In formula (3), R 9 represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. The number of carbon atoms in the hydrocarbon group is preferably 1 to 10, more preferably 1 to 5. R 9 may be substituted with a heteroatom-containing group. Examples of heteroatoms include an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, and a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom). In one embodiment, R 9 is an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. When a plurality of R 9 are included in one silyl group, they may be the same or different. When a plurality of silyl groups are included in one molecule of component E, R 9 may be different for each silyl group.

[0069] In formula (3), X represents a hydroxyl group or a hydrolyzable group. Examples of hydrolyzable groups include an alkoxy group, an oxime group, and an acetoxy group. In one embodiment, X is a hydroxyl group, a methoxy group, an ethoxy group, or an isopropoxy group. When a plurality of X are included in one silyl group, they may be the same or different. When a plurality of silyl groups are included in one molecule of component E, X may be different for each silyl group.

[0070] In formula (3), a is 1, 2, or 3.

[0071] Examples of the silyl group contained in component E include a dimethoxysilyl group, a trimethoxysilyl group, a diethoxysilyl group, a triethoxysilyl group, a triisopropoxysilyl group, a dimethoxymethylsilyl group, a diethoxymethylsilyl group, and a diisopropoxymethylsilyl group.

[0072] The number of silyl groups introduced into Component E is preferably more than 1.2 per molecule, more preferably 1.2 to 4.0, and even more preferably 1.5 to 2.5. If the number of silyl groups is within the above range, good curability can be imparted to the curable composition.

[0073] Alternatively, it is also possible to use a polyoxyalkylene polymer having only one silyl group at the terminal. Such a polymer can replace the plasticizer component. Furthermore, it is possible to use a polyoxyalkylene polymer obtained by the synthesis method described in JP-A-2021-75722.

[0074] The silyl group of Component E is preferably located at one or more molecular terminals, and more preferably at two or more molecular terminals. If the silyl group is located at the molecular terminal, good elongation can be imparted to the cured product.

[0075] Component E may be a commercially available product. Examples of commercially available Component E include Kaneka MS Polymer (registered trademark) S810, S257, S327 (all from Kaneka Corporation); Silyle (registered trademark) SAX220, SAT400, SAX510, SAX520, SAX580, SAX750, SAT145 (all from Kaneka Corporation); Exesta (registered trademark) ES-S2410, ES-S2420, ES-S3630 (all from AGC Inc.); HMS-1603, HMS-1207 (both from Huangma Technology).

[0076] [1.5.3. Physical Properties of Component E] The lower limit of the number average molecular weight of Component E is not particularly limited, preferably 2,000 or more, more preferably 10,000 or more, and even more preferably 20,000 or more. The upper limit of the number average molecular weight of Component E is preferably 50,000 or less, and preferably 30,000 or less.

[0077] The molecular weight distribution of Component E is preferably 1.6 or less, more preferably 1.5 or less, and even more preferably 1.2 or less. If the molecular weight distribution is too large, the viscosity of the curable composition increases, and the workability tends to deteriorate.

[0078] Such Component E can be obtained by the methods described in

[0011] to

[0058] of JP-A-2021-55010.

[0079] [1.6. Other Components] The curable composition may contain various additives in addition to the components described above. By containing these additives, various physical properties of the curable composition and the cured product can be adjusted. Examples of the additives are as follows. These additives may be used alone or in combination of two or more.

[0080] (Adhesion Promoter) The curable composition may contain an adhesion promoter. By adding an adhesion promoter, the risk of the sealing material peeling off from an adherend such as a siding board can be reduced (this peeling occurs due to fluctuations in the joint width or the like caused by an external force). In addition, the need to use a primer for improving adhesion may be eliminated. In this case, simplification of the construction work is expected.

[0081] Examples of the adhesion promoter include silane coupling agents. Specific examples of the silane coupling agents include isocyanate group-containing silanes (γ-isocyanatopropyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropylmethyldiethoxysilane, γ-isocyanatopropylmethyldimethoxysilane, etc.); amino group-containing silanes (γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldiethoxysilane, γ-ureidopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-benzyl-γ-aminopropyltrimethoxysilane, N-vinylbenzyl-γ-aminopropyltriethoxysilane, etc.); mercapto group-containing silanes (γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, etc.); carboxysilanes (β-carboxyethyltriethoxysilane, β-carboxyethylphenylbis(2-methoxyethoxy)silane, N-(β-carboxymethyl)aminoethyl-γ-aminopropyltrimethoxysilane, etc.); vinyl-type unsaturated group-containing silanes (vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane, γ-acryloyloxypropylmethyltriethoxysilane, etc.); halogen-containing silanes (γ-chloropropyltrimethoxysilane, etc.); isocyanurate silanes (tris(trimethoxysilyl)isocyanurate, etc.).In addition, amino-modified silyl polymers, silylated amino polymers, unsaturated amino-silane complexes, phenylamino long-chain alkylsilanes, aminosilylated silicones, silylated polyesters, etc., which are derivatives obtained by modifying silane coupling agents, can also be used as silane coupling agents.

[0082] When the content of component A is 100 parts by weight, the content of the adhesion promoter is preferably 0.1 to 20 parts by weight, and more preferably 0.5 to 10 parts by weight.

[0083] (Filler) The curable composition may contain a filler. Examples of fillers include wood powder; reinforcing fillers (pulp, cotton chips, asbestos, mica, walnut shell powder, rice husk powder, graphite, clay, silica (fumed silica, precipitated silica, crystalline silica, fused silica, dolomite, anhydrous silicic acid, hydrous silicic acid, etc.), carbon black, etc.); fillers (heavy calcium carbonate, colloidal calcium carbonate, magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium oxide, bentonite, organic bentonite, ferric oxide, red iron oxide, aluminum fine powder, flint powder, zinc oxide, activated zinc white, zinc powder, zinc carbonate, shirasu balloon, etc.); fibrous fillers (asbestos, glass fiber and glass filament, carbon fiber, Kevlar fiber, polyethylene fiber, etc.).

[0084] When the total content of component A is 100 parts by weight, the content of the filler is preferably 5 to 5000 parts by weight, more preferably 10 to 2500 parts by weight, and particularly preferably 15 to 1500 parts by weight.

[0085] (Physical property modifier) The curable composition may contain a physical property modifier for adjusting the tensile properties of the cured product. By using the physical property modifier, the hardness of the cured product can be increased, or conversely, the hardness of the cured product can be decreased and the elongation can be increased.

[0086] Examples of the physical property adjuster include alkylalkoxysilanes (such as methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, n-propyltrimethoxysilane, etc.); alkylisopropenoxysilanes (such as dimethyldiisopropenoxysilane, methyltriisopropenoxysilane, etc.); alkoxysilanes having functional groups (such as vinyldimethylmethoxysilane, γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)aminopropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, etc.); silicone varnishes; polysiloxanes.

[0087] When the total content of component A is 100 parts by weight, the content of the physical property adjuster is preferably 0.1 to 80 parts by weight, and more preferably 0.1 to 50 parts by weight.

[0088] (Thixotropic agent (anti-sagging agent)) The curable composition may contain a thixotropic agent (anti-sagging agent) in order to prevent sagging and improve workability.

[0089] Examples of the thixotropic agent include polyamide waxes; hydrogenated castor oil derivatives; metal soaps (such as calcium stearate, aluminum stearate, barium stearate, etc.).

[0090] When the total content of component A is 100 parts by weight, the content of the thixotropic agent is preferably 0.1 to 50 parts by weight, and more preferably 0.2 to 25 parts by weight.

[0091] (Photo-curable substance) The curable composition may contain a photocurable substance. A photocurable substance is a substance that undergoes a chemical change in a short time under the action of light and causes a physical property change (such as curing). By containing a photocurable substance, the adhesiveness (residual tack) of the cured product surface can be reduced. A typical photocurable substance can be cured, for example, by standing at room temperature for one day at a sunlit position indoors (such as near a window). Many photocurable substances are known, such as organic monomers, oligomers, resins, and compositions containing these, and the types thereof are not particularly limited. Examples of photocurable substances include unsaturated acrylic compounds, vinyl polycinnamates, and azide resins.

[0092] Specific examples of unsaturated acrylic compounds include (meth)acrylate esters of low molecular weight alcohols (such as ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, neopentyl alcohol, etc.); (meth)acrylate esters of alcohols modified with acids (such as bisphenol A, isocyanuric acid) or low molecular weight alcohols with ethylene oxide, propylene oxide, etc.; (meth)acrylate esters (such as polyether polyols having a polyether main chain and a hydroxyl group at the end, polymer polyols obtained by radical polymerization of vinyl monomers in polyols having a polyether main chain, polyester polyols having a polyester main chain and a hydroxyl group at the end, polyols having a vinyl-based or (meth)acrylic copolymer main chain and a hydroxyl group in the main chain, etc.); epoxy acrylate-based oligomers obtained by reacting epoxy resins (such as bisphenol A type, novolac type, etc.) with (meth)acrylic acid; urethane acrylate-based oligomers having a urethane bond and a (meth)acrylic group in the molecular chain obtained by reacting polyols, polyisocyanates, hydroxyl group-containing (meth)acrylates, etc.

[0093] When the total content of component A is 100 parts by weight, the content of the photocurable substance is preferably 0.01 to 30 parts by weight.

[0094] (Antioxidants and light stabilizers) The curable composition may contain an antioxidant and / or a light stabilizer. Various types of antioxidants and light stabilizers are known. For example, substances described in [Kenichi Saruwatari et al., "Antioxidant Handbook", Taiseisha, 1976] [Yoshijiro Oosawa, ed., "Deterioration and Stabilization of Polymer Materials", CMC, 1990, pages 235 - 242] and the like can be mentioned.

[0095] Examples of antioxidants include thioether-based antioxidants such as AdekaStab PEP-36 and AdekaStab AO-23 (all of the above are manufactured by ADEKA CORPORATION); phosphorus-based antioxidants such as Irgafos 38, Irgafos 168, and Irgafos P-EPQ (all of the above are manufactured by Ciba Specialty Chemicals); and hindered phenol-based antioxidants. Among those described above, hindered phenol-based antioxidants are preferred.

[0096] Specific examples of the hindered phenol-based antioxidant include 2,6-di-t-butyl-4-methylphenol, 2,6-di-t-butyl-4-ethylphenol, mono(or di or tri)(α-methylbenzyl)phenol, 2,2'-methylenebis(4-ethyl-6-t-butylphenol), 2,2'-methylenebis(4-methyl-6-t-butylphenol), 4,4'-butylidenebis(3-methyl-6-t-butylphenol), 4,4'-thiobis(3-methyl-6-t-butylphenol), 2,5-di-t-butylhydroquinone, 2,5-di-t-amylhydroquinone, triethylene glycol-bis-[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-t-butylanilino)-1,3,5-triazine, pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2'-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), 3,5-di-t-butyl-4-hydroxy-benzylphosphonate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, bis(3,5-di-t-butyl-4-hydroxybenzylphosphonic acid ethyl)calcium, tris-(3,5-di-t-butyl-4-hydroxybenzyl)isocyanurate, 2,4-bis[(octylthio)methyl]o-cresol, N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine, tris(2,4-di-t-butylphenyl)phosphite, 2-(5-methyl-2-hydroxyphenyl)benzotriazole, 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, 2-(3,5-Di-t-butyl-2-hydroxyphenyl)benzotriazole, 2-(3-t-butyl-5-methyl-2-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3,5-di-t-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3,5-di-t-amyl-2-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)-benzotriazole, methyl 3-[3-t-butyl-5-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]propionate-polyethylene glycol (molecular weight about 300) condensate, hydroxyphenylbenzotriazole derivative, 2-(3,5-di-t-butyl-4-hydroxybenzyl)-2-n-butylmalonic acid bis(1,2,2,6,6-pentamethyl-4-piperidyl), 2,4-di-t-butylphenyl 3,5-di-t-butyl-4-hydroxybenzoate may be mentioned.,

[0097] Examples of commercially available antioxidants include Nocrack 200, Nocrack M-17, Nocrack SP, Nocrack SP-N, Nocrack NS-5, Nocrack NS-6, Nocrack NS-30, Nocrack 300, Nocrack NS-7, Nocrack DAH (all of the above, manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.); AdekaStab AO-30, AdekaStab AO-40, AdekaStab AO-50, AdekaStab AO-60, AdekaStab AO-616, AdekaStab AO-635, AdekaStab AO-658, AdekaStab AO-80, AdekaStab AO-15, AdekaStab AO-18, AdekaStab 328, AdekaStab AO-37 (all of the above, manufactured by Adeka Corporation); Irganox-245, Irganox-259, Irganox-565, Irganox-1010, Irganox-1024, Irganox-1035, Irganox-1076, Irganox-1081, Irganox-1098, Irganox-1222, Irganox-1330, Irganox-1425WL (all of the above, manufactured by Ciba Specialty Chemicals); Sumilizer GM, Sumilizer GA-80, Sumilizer GS (all of the above, manufactured by Sumitomo Chemical Co., Ltd.).

[0098] Examples of the light stabilizer include ultraviolet absorbers (benzotriazole compounds such as Tinuvin P, Tinuvin 234, Tinuvin 320, Tinuvin 326, Tinuvin 327, Tinuvin 329, Tinuvin 213 (all of the above are from Ciba Specialty Chemicals)); triazine-based light stabilizers such as Tinuvin 1577; benzophenone compounds such as Chimassorb 81; benzoate compounds such as Tinuvin 120 (Ciba Specialty Chemicals); and hindered amine compounds). Among those described above, hindered amine compounds are preferred.

[0099] Specific examples of the hindered amine compounds include dimethyl succinate-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly[{6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidyl)imino}], N,N'-bis(3-aminopropyl)ethylenediamine-2,4-bis[N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino]-6-chloro-1,3,5-triazine condensate, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, and bis(2,2,6,6-tetramethyl-4-piperidinyl) succinate ester.

[0100] Examples of commercially available light stabilizers include Tinuvin 622LD, Tinuvin 144, Chimassorb 944LD, Chimassorb 119FL; (all of the above are from Ciba Specialty Chemicals), AdekaStab LA-52, AdekaStab LA-57, AdekaStab LA-62, AdekaStab LA-67, AdekaStab LA-63, AdekaStab LA-68, AdekaStab LA-82, AdekaStab LA-87 (all of the above are from ADEKA Corporation); Sanol LS-770, Sanol LS-765, Sanol LS-292, Sanol LS-2626, Sanol LS-1114, Sanol LS-744, Sanol LS-440 (all of the above are from Ciba Specialty Chemicals).

[0101] The antioxidant and the light stabilizer may be used in combination. By using them in combination, their respective effects may be further improved, and the heat resistance, weather resistance, etc. of the cured product may be improved. For example, in order to improve weather resistance, an ultraviolet absorber and a hindered amine compound (HALS) can be combined. This combination can further improve the effects of each drug and is preferable.

[0102] When the total content of component A is 100 parts by weight, the content of the antioxidant and / or the light stabilizer is preferably 0.1 to 20 parts by weight, respectively.

[0103] [2. Composition of the curable composition] In the curable composition, the lower limit of the content ratio (weight ratio) of component A / component B is preferably 1 / 99 or more, more preferably 10 / 90 or more, and even more preferably 20 / 80 or more. The upper limit of the content ratio (weight ratio) of component A / component B is preferably 99 / 1 or less, more preferably 90 / 10 or less, and even more preferably 80 / 20 or less. Blending both components within the above range tends to improve the storage stability of the curable composition.

[0104] In the curable composition, when the total content of component A, component B, and component E is 100 parts by weight, the lower limit of the content of component C is preferably 0.01 part by weight or more, more preferably 0.05 part by weight or more, still more preferably 0.1 part by weight or more, and particularly preferably 0.5 part by weight or more. When the total content of component A, component B, and component E is 100 parts by weight, the upper limit of the content of component C is preferably 10 parts by weight or less, more preferably 8 parts by weight or less, and still more preferably 5 parts by weight or less.

[0105] In the curable composition, when the total content of component A, component B, and component E is 100 parts by weight, the lower limit of the content of component D is preferably 0.1 part by weight or more, and more preferably 0.5 part by weight or more. When the total content of component A, component B, and component E is 100 parts by weight, the upper limit of the content of component D is preferably 5 parts by weight or less, and more preferably 3 parts by weight or less.

[0106] In the curable composition, when the total content of component A and component B is 100 parts by weight, the lower limit of the content of component E is preferably 8 parts by weight or more, and more preferably 10 parts by weight or more. When the total content of component A and component B is 100 parts by weight, the upper limit of the content of component E is preferably 200 parts by weight or less, more preferably 150 parts by weight or less, still more preferably 100 parts by weight or less, and particularly preferably 50 parts by weight or less.

[0107] 〔3. Form of the curable composition〕 The curable composition containing components A to D may be of a one-component type or a multi-component type. The one-component type curable composition is obtained by premixing all the compounding components and then storing them in a sealed manner. The one-component type curable composition cures due to moisture in the environment after use. In the multi-component type curable composition, a curing catalyst and other components are prepared separately and mixed together at the time of use. The multi-component type curable composition may be provided with other agents (such as colorants) having an optional configuration in addition to the above components.

[0108] When the curable composition is prepared as a multi-component type, a colorant can be further added when the components are mixed. For example, a colorant obtained by mixing a pigment, a plasticizer, and, if necessary, a filler and pasting it is preferable because of its high workability.

[0109] In addition, a retarder can be added to the multi-component curable composition when the main agent and the curing agent are mixed. Thereby, the curing rate can be finely adjusted at the work site.

[0110] 〔4. Cured product〕 A cured product is obtained from the above-mentioned curable composition by a known method. For example, the above-mentioned curable composition can absorb ambient moisture and spontaneously change into a cured product. The use of the cured product is not particularly limited. As an example, building and industrial sealants, electrical and electronic component materials (such as back sealants for solar cells), electrical insulation materials (such as insulating coating materials for wires and cables), adhesives, bonding agents, elastic adhesives, contact adhesives, adhesives for tiles, paints, coating materials, seal materials such as can lids, potting agents for electrical and electronics, films, gaskets, casting materials, various molding materials, artificial marble, rust and waterproof sealants for cut portions of wired glass or laminated glass, and waterproof agents can be mentioned.

[0111] In one embodiment, the cured product is in the form of a film. The lower limit of the thickness of the film to be produced can be 0.1 mm or more, 0.5 mm or more, 1 mm or more, 5 mm or more, or 10 mm or more. The upper limit of the thickness of the film to be produced can be 100 mm or less, 90 mm or less, 80 mm or less, 70 mm or less, 60 mm or less, or 50 mm or less.

[0112] The film-like cured product can be produced, for example, by applying the curable composition to a substrate and then curing it. It may be used in a state where the film is peeled off from the substrate, or it may be used in a state where the substrate and the film are integrated. Examples of the uses of the film-like cured product include sealants, coating agents, and adhesives.

[0113] 〔5. Summary〕 The present invention includes the following aspects. <1> A curable composition containing the following components A to D: Component A: A (meth)acrylic block copolymer having a silyl group; Component B: A (meth)acrylic random copolymer having a silyl group; Component C: A polyvalent amine; Component D: A curing catalyst; Here, the above Component A has an XY diblock structure or an XYX triblock structure having an X block and a Y block in the molecule, the repeating unit derived from the silyl group-containing (meth)acrylate monomer contained in the above X block is more than 2.0 on average, the repeating unit derived from the silyl group-containing (meth)acrylate monomer contained in the above Y block is 0 wt% or more and less than 5 wt% based on the weight of all the repeating units contained in the above Y block, the molecular weight distribution (Mw / Mn) is 1.8 or less; Here, the above Component B has an average of 1.0 or more silyl groups derived from the silyl group-containing (meth)acrylate monomer per molecule, the molecular weight distribution (Mw / Mn) is more than 1.8. <2> The above Component A and / or the above Component B contains 1 wt% or more of a repeating unit derived from CH2=C(R 1 )COOR 2 (wherein R 1 is a hydrogen atom or a methyl group, and R 2 is a group having 9 or more carbon atoms), the curable composition according to <1>. <3> The number average molecular weight of the above Component A and / or the above Component B is 2,000 to 50,000, the curable composition according to <1> or <2>. <4> The silyl group possessed by the above Component B is represented by the following general formula (2), the curable composition according to any one of <1> to <3>: -W-(CH2) n -Si(R6 ) 3-a (X) a (2) In the formula, W is a divalent group other than CH2, n is an integer of 5 to 20, R 8 represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms, R 8 may be substituted with a heteroatom-containing group, When a plurality of R 8 are contained in one silyl group, they may be the same or different, R 8 may be different for each silyl group, X represents a hydroxyl group or a hydrolyzable group, When a plurality of X are contained in one silyl group, they may be the same or different, X may be different for each silyl group, a is 1, 2 or 3. <5> The curable composition according to any one of <1> to <4>, further containing the following component E: Component E: a polyoxyalkylene polymer having a silyl group; Here, the above component E has one or more silyl groups represented by the following general formula (3) in the molecule: -Si(R 9 ) 3-a (X) a (3) In the formula, R 9 represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms, R 9 may be substituted with a heteroatom-containing group, When a plurality of R 9 are contained in one silyl group, they may be the same or different, R 9 may be different for each silyl group, X represents a hydroxyl group or a hydrolyzable group, When a plurality of X are contained in one silyl group, they may be the same or different, X may be different for each silyl group, a is 1, 2 or 3. <6> The curable composition according to <5>, wherein the number average molecular weight of the above component E is 3,000 to 50,000. <7> A cured product obtained by curing the curable composition according to any one of <1> to <6>.

Examples

[0114] 〔Measurement method〕 [Number average molecular weight] The following apparatus was used for the measurement of the number average molecular weight. The measured value is the polystyrene equivalent molecular weight. ·Liquid delivery system: HLC-8120GPC (Tosoh Corporation) ·Column: TSK-GEL H type (Tosoh Corporation) ·Solvent: THF

[0115] [Introduction rate of terminal silyl group] 1 The introduction rate of the terminal silyl group was calculated from the results of 1H-NMR measurement. 1 The following apparatus was used for 1H-NMR measurement. ·Measuring instrument: JNM-LA400 (JEOL Ltd.) ·Solvent: CDCl3

[0116] [Tensile properties of cured product] The curable composition was cured under the conditions of 23 °C and 50% RH to obtain a cured product. According to JIS K 6251, a dumbbell-shaped No. 3 test piece was obtained from the cured product, and the tensile properties were measured. The measurement of the tensile properties was carried out at 23 °C and 55% RH using an autograph. The evaluation items were the stress at 100% elongation, the stress at break, and the elongation at break.

[0117] [Viscosity of curable composition] The viscosity of the prepared curable composition was measured using an E-type viscometer (VICOMETER TV-25type H, Toki Sangyo Co., Ltd.). The measurement temperature was 23°C.

[0118] Also, the prepared curable composition was placed in a storage container and stored at 50°C for 1 week or 2 weeks. The viscosity of the curable composition after storage was measured by the above-described method.

[0119] 〔Materials〕 The materials used in the examples and comparative examples are as follows. ● Component A: (Meth)acrylic block copolymer having a silyl group · That obtained in Production Example 1 ● Component B: (Meth)acrylic random copolymer having a silyl group · That obtained in Production Example 2 ● Component C: Polyvalent amine · Modified aliphatic polyamine (FXJ-8074-D, T&K TOKA Co., Ltd.) ● Component D: Curing catalyst · Curing catalyst (Neostan U-220H, Nitto Kasei Co., Ltd., dibutyltin) ● Component E: Polyoxyalkylene polymer having a silyl group · That obtained in Production Example 3 ● Adhesion promoter · N-2-(Aminoethyl)-3-aminopropyltrimethoxysilane (KBM-603, Shin-Etsu Chemical Co., Ltd.) ● Dehydrating agent · Vinyltrimethoxysilane (Silquest A-171, MOMENTIVE)

[0120] 〔Production Example 1: Synthesis of (Meth)acrylic Block Copolymer (A)〕 A (meth)acrylic block copolymer (A) having a silyl group was synthesized by the following procedure. (Preparation) 1. A 2000 mL three-necked flask was prepared. 108 g of ethyl acrylate, 707 g of n-butyl acrylate and 186 g of octadecyl acrylate were charged into the flask and mixed. This mixture is referred to as the “(meth)acrylate monomer mixture”. 2. Another stirring container was prepared. 52.7 mg of cupric bromide (CuBr2), 54.4 mg of hexamethyltris(2-aminoethyl)amine (Me6TREN) and 1.82 g of methanol were charged into the stirring container and stirred under a nitrogen stream until a homogeneous solution was obtained. This homogeneous solution is referred to as the “copper solution”. The copper contained in the copper solution corresponds to 15 ppm with respect to the total amount of the (meth)acrylate monomer mixture. 3. Yet another stirring container was prepared. 30.8 mL of methanol, 1.0 g of ascorbic acid and 1.6 mL of triethylamine were charged into the stirring container and stirred under a nitrogen stream to obtain a homogeneous solution. This homogeneous solution is referred to as the “ascorbic acid solution”. (First step) 4. Into a stirrer were charged 5.60 g of ethyl α-bromobutyrate (initiator; 0.029 mol), 20 wt% of the total amount of the (meth)acrylate monomer mixture, 10 g of 3-methacryloxypropylmethyldimethoxysilane (0.045 mol; 1.5 molar equivalents with respect to the initiator), 107.68 g of methanol, and the total amount of the copper solution, and the mixture was stirred for 30 minutes under a nitrogen stream to obtain a homogeneous solution. The stirrer used at this time was a jacket temperature-controlled stirring device, and the jacket temperature was set at 45°C. 5. When the temperature in the polymerization system reached 40°C or higher, the polymerization reaction was initiated by continuously dropping the ascorbic acid solution. The dropping rate of the ascorbic acid solution at this time was set such that 144 mg of ascorbic acid was introduced into the polymerization system per hour. 6. When the temperature in the polymerization system was monitored, the temperature increased simultaneously with the start of the dropwise addition of ascorbic acid. After reaching the maximum temperature, the temperature gradually decreased. When the temperature difference obtained by subtracting the jacket temperature from the temperature in the polymerization system reached 1°C, a small amount of the reaction solution in the polymerization system was sampled and analyzed by gas chromatography. As a result, 90% by weight of the (meth)acrylic acid ester monomer mixture initially charged had been consumed. (Second step) 7. The remainder of the (meth)acrylic acid ester monomer mixture that had not been charged in the first step (80% by weight of the total amount) was continuously dropped into the polymerization system over 90 minutes. The dropping rate of the ascorbic acid solution at this time was set such that 48 mg of ascorbic acid was charged into the polymerization system per hour. Also, sampling was carried out sequentially and analyzed by gas chromatography. Then, polymerization was carried out until 88% by weight of the total amount of the (meth)acrylic acid ester monomer mixture charged into the polymerization system had been consumed. (Third step) 8. 11 g of 3-methacryloxypropylmethyldimethoxysilane (0.049 mol; 1.6 molar equivalents relative to the initiator) was charged into the polymerization system. The continuous dropping of the ascorbic acid solution was continued until 98% by weight of the total amount of the (meth)acrylic acid ester monomer mixture charged into the polymerization system had been consumed. Thereafter, the dropping of the ascorbic acid solution was terminated and the polymerization was terminated. 9. After changing the jacket temperature to 80°C, the solvent was devolatilized. For devolatilization, first a diaphragm pump was used, and then a vacuum pump was used. After completion of devolatilization, it was cooled until the jacket temperature became 60°C or lower. (Purification) 10. 1000 g of butyl acetate was charged into the jacket temperature-controlled stirring device and mixed and stirred until it became a homogeneous solution with the polymer after devolatilization. An adsorbent was added to this homogeneous solution and stirred for 1 hour. As the adsorbent, 10 g of Kyoward 500SH (Kyowa Chemical Industry Co., Ltd.) and 10 g of Kyoward 700SEN-S (Kyowa Chemical Industry Co., Ltd.) were used. 11. After the stirring was completed, the obtained mixture was filtered through a filter equipped with a bag filter cloth. As a result, a clear polymer solution was obtained. To this solution, 1.5 g of an antioxidant (Sumilizer GS, Sumitomo Chemical Co., Ltd.) was added and mixed until homogeneous. Then, the solvent was removed from the solution using a diaphragm pump first and then a vacuum pump. Thus, a (meth)acrylic block copolymer (A) having a silyl group was obtained.

[0121] (Meth)acrylic block copolymer (A) is an XYX type block copolymer with a number average molecular weight of 55,000, a molecular weight distribution of 1.11, and 2.1 silyl groups introduced per molecule. In addition, the X block of the (meth)acrylic block copolymer (A) had an average of 2.1 repeating units derived from a silyl group-containing (meth)acrylic acid ester monomer per molecule of the copolymer. The Y block of the (meth)acrylic block copolymer (A) had 1.1% by weight of repeating units derived from a silyl group-containing (meth)acrylic acid ester monomer (based on the weight of all repeating units contained in the Y block). Note that the number of repeating units derived from the silyl group-containing (meth)acrylic acid ester monomer contained in the Y block is extremely small. Therefore, when calculated to two significant figures, both the repeating units derived from the silyl group-containing (meth)acrylic acid ester monomer contained in the whole molecule and those contained in the whole X block are 2.1.

[0122] [Production Example 2: Synthesis of (meth)acrylic random copolymer (B)] A (meth)acrylic random copolymer (B) having a silyl group was synthesized according to the following procedure. 1. A separable flask equipped with a stirrer and a reflux condenser was prepared. 210.0 g of butyl acetate was charged and nitrogen bubbling was carried out at room temperature for 30 minutes. Thus, a polymerization solvent was obtained. 2. A three-necked flask equipped with a stirrer was prepared. 294.0 g of butyl acrylate and 6.0 g of 3-methacryloxypropylmethyldimethoxysilane were charged and a homogeneous solution was obtained by stirring and mixing. Thereafter, nitrogen bubbling was carried out for 30 minutes. In this way, a monomer solution was obtained. 3. A two-necked flask was prepared. 2.97 g of azobis-2-methylbutyronitrile was charged and stirred and mixed with 29.7 g of butyl acetate to obtain a homogeneous solution. Thereafter, nitrogen bubbling was carried out for 30 minutes. In this way, an initial initiator solution was obtained. 4. Another two-necked flask was prepared. 1.19 g of azobis-2-methylbutyronitrile was charged and stirred and mixed with 11.90 g of butyl acetate to obtain a homogeneous solution. Thereafter, nitrogen bubbling was carried out for 30 minutes. In this way, an additional initiator solution was obtained. 5. The entire amount of the initial initiator solution obtained in Step 3 was added to the monomer solution obtained in Step 2. Thereafter, nitrogen bubbling was carried out for 15 minutes. 6. A separable flask charged with a polymerization solvent was heated in an oil bath to an internal temperature of 105 °C. The mixture obtained in Step 5 was dropped into the polymerization solvent to initiate polymerization. The dropping rate was adjusted so that the entire amount of the mixture obtained in Step 5 was dropped over about 5 hours. 7. After completion of dropping, the contents of the separable flask were stirred for about 1 hour. 8. The entire amount of the additional initiator solution was added to the separable flask over about 0.5 hours. 9. The contents of the separable flask were stirred for about 2 hours. Thereafter, the pressure was reduced using an evaporator to remove butyl acetate. In this way, a (meth)acrylic random copolymer (B) was obtained. The (meth)acrylic random copolymer has a structure in which dimethoxysilyl groups are randomly introduced into the main chain mainly composed of butyl acrylate. The number average molecular weight of the (meth)acrylic random copolymer (B) was 13,700, the weight average molecular weight was 26,100, and the molecular weight distribution was 1.9.

[0123] [Production Example 3: Synthesis of a polyoxyalkylene polymer (E) having a silyl group] A polyoxyalkylene polymer (E) having a silyl group was synthesized according to the following procedure. 1. Propylene oxide was polymerized to obtain a polypropylene oxide having a number average molecular weight of about 16,400. Polyoxypropylene triol (molecular weight: about 3,000) was used as the initiator. A zinc hexacyanocobaltate glyme complex was used as the catalyst. The obtained polypropylene oxide had hydroxyl groups at three terminals of the molecule. 2. 1.2 equivalents of NaOMe was added as a methanol solution to the hydroxyl groups at the terminals of the polypropylene oxide molecule. Methanol was distilled off. 3. Allyl chloride was added to convert the hydroxyl groups at the terminals of the polypropylene oxide molecule into allyl groups. Thereby, unpurified allyl group-terminated polypropylene oxide was obtained. 4. 300 parts by weight of n-hexane and 300 parts by weight of water were mixed with 100 parts by weight of the unpurified allyl group-terminated polypropylene oxide and stirred. Thereafter, water was removed by centrifugation. 5. 300 parts by weight of water was mixed again with the obtained solution and stirred. Thereafter, water was removed by centrifugation. 6. n-Hexane was removed by devolatilization under reduced pressure. Thereby, purified allyl group-terminated polypropylene oxide was obtained. 7. 1.80 parts by weight of methyldimethoxysilane was added to 100 parts by weight of the purified allyl group-terminated polypropylene oxide, and the mixture was reacted at 90 °C for 2 hours. A platinum vinylsiloxane complex isopropanol solution (platinum content: 3 wt%) was used as the catalyst. The in-system concentration of the catalyst was 150 ppm. Thereby, a polyoxyalkylene polymer was obtained.

[0124] The polyoxyalkylene polymer (E) is a polypropylene oxide having a methyldimethoxysilyl group introduced at the terminal, and the number average molecular weight was about 16,400. 1 When measured by 1H-NMR, the introduction rate of the methyldimethoxysilyl group at the molecular terminal of the polyoxyalkylene polymer (E) was 70%.

[0125] [Examples 1 to 4, Comparative Example 1, Reference Example 1] Samples for physical property evaluation were prepared according to the following procedure. 1. Each component was prepared in the amounts (unit: g) shown in Table 1. 2. Each component was put into a 150 cc plastic cup and stirred with a spatula. 3. Using a planetary stirring and degassing device (ARE-310, Shinki Co., Ltd.), stirring (1600 rpm × 90 seconds) and degassing (2200 rpm × 300 seconds) were performed to obtain a curable composition.

[0126] [Results] The results are shown in Table 1. [Table 1]

[0127] The curable composition according to Comparative Example 1 contained only Component A and did not contain Component B. The curable composition according to Comparative Example 1 gelled within one week after storage at 50°C. On the other hand, the curable compositions according to Examples 1 to 4 contained both Component A and Component B. These curable compositions did not gel even after 2 weeks had passed after storage at 50°C. From this, it was shown that by incorporating Component B into a curable composition containing Component A, the storage stability was improved. Also, depending on the incorporation of Component B, the mechanical properties of the resulting cured product did not change significantly. Note that the cured product obtained from the curable composition according to Reference Example 1 had significantly different mechanical properties compared to the cured products according to the Examples and Comparative Example (in particular, the stress at break and the elongation at break were significantly reduced). That is, it was shown that it was necessary to contain Component A in order to ensure sufficient mechanical properties of the cured product. [Industrial Applicability]

[0128] The curable composition according to one embodiment of the present invention can be suitably used for adhesives, sealing materials, adhesives, mold release agents, vibration damping materials, vibration control materials, sound insulation materials, foaming materials, paints, spraying materials, etc.

Claims

1. A curable composition containing the following components A to D: Component A: A (meth)acrylic block copolymer having a silyl group; Component B: A (meth)acrylic random copolymer having a silyl group; Component C: A polyvalent amine; Component D: A curing catalyst; Here, the above Component A has an XY diblock structure or an XYX triblock structure having an X block and a Y block in the molecule, the repeating unit derived from the silyl group-containing (meth)acrylate monomer contained in the above X block is more than 2.0 on average, the repeating unit derived from the silyl group-containing (meth)acrylate monomer contained in the above Y block is 0% by weight or more and less than 5% by weight based on the weight of all the repeating units contained in the above Y block, the molecular weight distribution (Mw / Mn) is 1.8 or less; Here, the above Component B has an average of 1.0 or more silyl groups derived from the silyl group-containing (meth)acrylate monomer per molecule, the molecular weight distribution (Mw / Mn) is more than 1.

8.

2. The above component A and / or the above component B is CH ２ =C(R １ )COOR ２ (In the formula, R １ is a hydrogen atom or a methyl group, and R ２ is a group having 9 or more carbon atoms), and contains 1% by weight or more of a repeating unit derived therefrom. The curable composition according to claim 1.

3. The curable composition according to claim 1, wherein the number average molecular weight of the above Component A and / or the above Component B is 2,000 to 50,000.

4. The curable composition according to claim 1, wherein the silyl group possessed by the above Component B is represented by the following general formula (2): -W-(CH ２ ) ｎ -Si(R ６ ) ３－ａ (X) ａ (2) In the formula, W is a divalent group other than CH ２ and is a divalent group other than n is an integer of 5 to 20, R ８ represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms, R ８ which may be substituted with a heteroatom-containing group, R is included in one of the silyl groups ８ When a plurality of them are included, they may be the same or different, R ８ may vary for each cyryl group, X represents a hydroxyl group or a hydrolyzable group, when a plurality of Xs are contained in one silyl group, they may be the same or different, X may be different for each silyl group, a is 1, 2 or 3.

5. The curable composition according to claim 1, further containing the following Component E: Component E: A polyoxyalkylene-based polymer having a silyl group; Here, the above Component E has one or more silyl groups represented by the following general formula (3) in the molecule: -Si(R ９ )( ３－ａ (X) ａ (3) In the formula, R ９ represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms, R ９ which may be substituted with a heteroatom-containing group, R is included in one of the silyl groups ９ When a plurality of them are included, they may be the same or different R ９ may vary for each silyl group, X represents a hydroxyl group or a hydrolyzable group, when a plurality of Xs are contained in one silyl group, they may be the same or different, X may be different for each silyl group, a is 1, 2 or 3.

6. The curable composition according to claim 5, wherein the number average molecular weight of the above Component E is 3,000 to 50,000.

7. A cured product obtained by curing the curable composition according to any one of claims 1 to 6.

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