Hardening components and hardening agents

Abstract

To provide a curable composition that is less prone to gelation when stored at high temperatures, has a moderately low viscosity, and yields a cured product with excellent tensile strength, and a cured product of the curable composition. [Solution] In a curable composition comprising a polyoxyalkylene polymer (A) having reactive silicon groups, a (meth)acrylic polymer (B) having reactive silicon groups, and a curing catalyst (D), the (meth)acrylic polymer (B) is a (meth)acrylic polymer having constituent units derived from an epoxy group-containing (meth)acrylic acid ester, and the curable composition contains a polyfunctional thiol (C).

Description

Technical Field

[0001] The present invention relates to a curable composition containing a polyoxyalkylene polymer (A) having a reactive silicon group, a (meth)acrylic polymer (B) having a reactive silicon group, a polyfunctional thiol (C), and a curing catalyst (D), and a cured product of the curable composition.

Background Art

[0002] An organic polymer having at least one reactive silicon group in the molecule can crosslink by forming a siloxane bond accompanied by a hydrolysis reaction of the silyl group due to moisture or the like even at room temperature. It is known that an organic polymer having a reactive silicon group has a property of giving a rubbery cured product by such a crosslinking reaction.

[0003] Among organic polymers having a reactive silicon group, polyoxyalkylene polymers having a reactive silicon group are widely used in building sealing materials and industrial sealing materials. In these applications, long-term excellent weather resistance is required for the cured product of the curable composition containing a polyoxyalkylene polymer having a reactive silicon group.

[0004] As a method for improving the weather resistance of a cured product, it is known to combine and blend a (meth)acrylic polymer having a reactive silicon group and a polyoxyalkylene polymer having a reactive silicon group in a curable composition (see Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Architectural and industrial sealants require that they do not gel when stored at high temperatures and exhibit a moderately low viscosity for ease of application. If the viscosity is too low, dripping may occur, and it may be difficult to adjust the amount of sealant injected from the injection device used for sealing. If the viscosity is too high, it may be difficult to achieve uniform and stable application. Furthermore, sealants are often required to form cured products with excellent mechanical properties such as tensile strength (Tb). However, in curable compositions containing a polyoxyalkylene polymer having reactive silicon groups and a (meth)acrylic polymer having reactive silicon groups, as described in Patent Document 1, the curable composition may gel when stored at high temperatures, and it is difficult to achieve both a moderately low viscosity and excellent tensile strength in the cured product.

[0007] The present invention has been made in view of the above problems, and aims to provide a curable composition that does not easily gel when stored at high temperatures, has a moderately low viscosity, and gives a cured product having excellent tensile strength, and a cured product of the curable composition. [Means for solving the problem]

[0008] The present inventors have found that the above problems can be solved by using a (meth)acrylic polymer having constituent units derived from an epoxy group-containing (meth)acrylic acid ester as the (meth)acrylic polymer (B) in a curable composition comprising a polyoxyalkylene polymer (A) having a reactive silicon group, a (meth)acrylic polymer (B) having a reactive silicon group, and a curing catalyst (D), and by including a polyfunctional thiol (C) in the curable composition, thereby completing the present invention.

[0009] More specifically, the present invention provides the following (1) to (8). (1) comprising a polyoxyalkylene polymer having a reactive silicon group (A), a (meth)acrylic polymer having a reactive silicon group (B), a polyfunctional thiol (C), and a curing catalyst (D), (Meta)acrylic polymer (B) has a molecular chain containing a structural unit derived from (meta)acrylic acid ester and a structural unit derived from (meta)acrylic acid ester having an epoxy group. The ratio of the weight of the structural unit derived from (meta)acrylic acid ester having an epoxy group to the weight of (meta)acrylic polymer (B) is 0.1 to 5% by weight. The reactive silicon group is represented by the following formula (1): -SiR 1 a X 3-a (1) (In formula (1), R 1 is a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms, or a triorganosiloxy group represented by R 0 3SiO-, R 0 is a hydrocarbon group having 1 to 20 carbon atoms, X is a hydroxyl group or a hydrolyzable group, and a is 0, 1, or 2.) A curable composition represented by the group. (2) The curable composition according to (1), which contains a tertiary amine (E). (3) The number average molecular weight of the polyoxyalkylene polymer (A) is 5,000 to 30,000, The weight average molecular weight of the polyoxyalkylene polymer (A) is 20,000 to 36,000, and the curable composition according to (1) or (2). (4) The number average molecular weight of the (meta)acrylic polymer (B) is 3,000 to 60,000, (The weight average molecular weight of the (meta)acrylic polymer (B) is 6,000 to 180,000, and the curable composition according to any one of (1) to (3). (5) The ratio W A of the polyoxyalkylene polymer (A) to the weight W B of the (meta)acrylic polymer (B) is 95 / 5 to 5 / 95, and the curable composition according to any one of (1) to (4). A / W B is 95 / 5 to 5 / 95, and the curable composition according to any one of (1) to (4). (6) The curable composition according to any one of (1) to (5), wherein the polyfunctional thiol (C) is a compound having a secondary thiol group. (7) The curable composition according to any one of (1) to (6), wherein the amount of polyfunctional thiol (C) is 0.01 to 20 parts by weight per 100 parts by weight of the total weight of polyoxyalkylene polymer (A) and (meth)acrylic polymer (B). (8) The curable composition according to (2), wherein the amount of tertiary amine (E) is 0.01 to 10 parts by weight with respect to 100 parts by weight of the total weight of polyoxyalkylene polymer (A) and (meth)acrylic polymer (B). (9) A cured product of any one of the curable compositions described in (1) to (8). [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a curable composition that does not easily gel when stored at high temperatures, has a moderately low viscosity, and gives a cured product having excellent tensile strength, as well as a cured product of the curable composition. [Modes for carrying out the invention]

[0011] The present invention will be described in detail below.

[0012] ≪Curable composition≫ The curable composition comprises a polyoxyalkylene polymer (A) having reactive silicon groups, a (meth)acrylic polymer (B) having reactive silicon groups, a polyfunctional thiol (C), and a curing catalyst (D). The molecular chain of the (meth)acrylic polymer (B) contains constituent units derived from (meth)acrylic acid ester, and also contains constituent units derived from (meth)acrylic acid ester having an epoxy group. The ratio of the weight of the constituent units derived from the epoxy group-containing (meth)acrylic acid ester to the weight of the (meth)acrylic polymer (B) is 0.1 to 5% by weight. The curable composition may optionally contain various other additives.

[0013] The above curable composition is less prone to gelation when stored at high temperatures, has a moderately low viscosity, and yields a cured product with excellent tensile strength.

[0014] The following describes the essential and optional components that the curable composition may contain.

[0015] <Polyoxyalkylene polymer (A)> The polyoxyalkylene polymer (A) (hereinafter sometimes simply referred to as "polymer (A)") has reactive silicon groups. The reactive silicon group is the group represented by the following formula (1). -SiR 1 a X 3-a (1) In formula (1), R 1 is a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms, or R 0 It is a triorganosiloxy group represented as 3SiO-. In the triorganosiloxy group, there are three R 0 These are hydrocarbon groups with 1 to 20 carbon atoms. 0 They may be the same or they may be different. X is a hydroxyl group or a hydrolyzable group. a is 0, 1, or 2. R 1 For each of , and X, if there are multiple of them, then multiple R 1 , and multiple X's, may be the same or different.

[0016] Polymer (A) has a polymer backbone and polymer chain ends bonded to the polymer backbone. In the specification and claims of this application, the polymer backbone is also referred to as the "main chain structure". The polymer backbone is a structure in which multiple structural units derived from monomers are continuously bonded together. There may be one type of monomer or multiple types.

[0017] Polymer chain ends are the parts located at the ends of polymer (A). The number of polymer chain ends in polymer (A) is 2 if the main chain structure is linear, and 3 or more if the polymer backbone is branched. If polymer (A) is a mixture of polymers with a linear main chain structure and polymers with a branched main chain structure, the number of polymer chain ends will be between 2 and 3 on average.

[0018] Reactive silicon groups can be present in the polymer backbone and at the polymer chain ends. Furthermore, two or more reactive silicon groups may be present at the polymer chain ends. When using a curable composition in adhesives, sealants, elastic coatings, or other adhesives, it is preferable that the reactive silicon groups in polymer (A) are present at the polymer chain ends.

[0019] (Reactive silicon group) Reactive silicon groups are groups that can generate silanol groups through hydrolysis. When reactive silicon groups generate silanol groups, polymer (A) is crosslinked by condensation reactions between the silanol groups. As mentioned above, the reactive silicon group is the group represented by formula (1) above.

[0020] R in equation (1) 1 Specific examples include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-hexyl, 2-ethylhexyl, and n-dodecyl; unsaturated hydrocarbon groups such as vinyl, isopropenyl, and allyl; alkoxymethyl groups such as methoxymethyl; halogenated methyl groups such as chloromethyl; cycloalkyl groups such as cyclohexyl; aryl groups such as phenyl, toluyl, and 1-naphthyl; and aralkyl groups such as benzyl. Among these groups, alkyl groups and aryl groups are preferred, methyl, ethyl, and phenyl groups are more preferred, methyl and ethyl groups are even more preferred, and methyl groups are particularly preferred. 1 If multiple R 1 These may be the same group, or a combination of two or more different groups.

[0021] In formula (1), X is a hydroxyl group or a hydrolyzable group. The hydrolyzable group is not particularly limited and may be any known hydrolyzable group. Specific examples of hydrolyzable groups include hydrogen atoms, halogen atoms, alkoxy groups, acyloxy groups, ketoximate groups, amino groups, amide groups, acid amide groups, aminooxy groups, mercapto groups, and alkenyloxy groups. Among these, alkoxy groups, acyloxy groups, ketoximate groups, and alkenyloxy groups are preferred, and alkoxy groups such as methoxy groups and ethoxy groups are more preferred because they are mildly hydrolyzable and easy to handle. Methoxy groups are preferred because they allow for easy adjustment of the curability of the curable composition.

[0022] The reactive silicon group represented by formula (1) is not particularly limited. Specific examples of the reactive silicon group represented by formula (1) include dimethoxymethylsilyl group, diethoxymethylsilyl group, trimethoxysilyl group, triethoxysilyl group, dimethoxyphenylsilyl group, methoxymethyldimethoxysilyl group, methoxymethyldiethoxysilyl group, triisopropenyloxysilyl group, and triacetoxysilyl group. Among these, the dimethoxymethylsilyl group and the trimethoxysilyl group are preferred because they facilitate the synthesis of polymer (A). The trimethoxysilyl group and the methoxymethyldimethoxysilyl group are preferred because they exhibit excellent curability. The dimethoxymethylsilyl group is particularly preferred because of its excellent stability.

[0023] (Regarding the main chain structure of polymer (A)) Polymer (A) is a polyoxyalkylene polymer. Therefore, the main chain structure of the polymer consists of a polyoxyalkylene polymer. Specifically, the main chain structure of polymer (A) can be made of polyoxyalkylene polymers such as polyoxyethylene polymer, polyoxypropylene polymer, polyoxybutylene polymer, polyoxytetramethylene polymer, polyoxyethylene-polyoxypropylene copolymer, and polyoxypropylene-polyoxybutylene copolymer.

[0024] Because it exhibits excellent deep curing properties as a one-component composition, and also has excellent adhesive properties, polyoxypropylene is preferred as the main chain structure among polyoxyalkylene polymers.

[0025] Polyoxyalkylene polymers are -R 3 It is a polymer having repeating units represented by -O-. 3 R is a linear or branched alkylene group having 1 to 14 carbon atoms. 3 As such, linear or branched alkylene groups having 2 to 4 carbon atoms are more preferred. -R 3 Specific examples of repeating units represented by -O- include -CH2O-, -CH2CH2O-, -CH2CH(CH3)O-, -CH2CH(C2H5)O-, -CH2C(CH3)(CH3)O-, and -CH2CH2CH2CH2O-. The main chain structure of a polyoxyalkylene polymer may consist of only one type of repeating unit or of two or more types of repeating units. In particular, when the curable composition is used as a sealant, adhesive, etc., a polyoxypropylene polymer having 50% or more, preferably 80% or more by weight of oxypropylene repeating units in the polymer main chain structure is preferred as the polyoxyalkylene polymer. This is because such a polyoxyalkylene polymer is amorphous and has relatively low viscosity.

[0026] The main chain structure of the polyoxyalkylene polymer may be linear or branched.

[0027] As for polyoxyalkylene polymers, polymers obtained by a ring-opening polymerization reaction of a cyclic ether compound using a polymerization catalyst in the presence of an initiator are preferred.

[0028] Examples of cyclic ether compounds include ethylene oxide, propylene oxide, butylene oxide, tetramethylene oxide, and tetrahydrofuran. These cyclic ether compounds may be used individually or in combination of two or more. Among these cyclic ether compounds, propylene oxide is particularly preferred because it yields amorphous and relatively low-viscosity polyether polymers.

[0029] Specific examples of initiators include alcohols such as butanol, ethylene glycol, propylene glycol, propylene glycol monoalkyl ether, butanediol, hexamethylene glycol, neopentyl glycol, diethylene glycol, dipropylene glycol, triethylene glycol, glycerin, trimethylolmethane, trimethylolpropane, pentaerythritol, and sorbitol; and polyoxyalkylene polymers such as polyoxypropylenediol, polyoxypropylenetriol, polyoxyethylenediol, and polyoxyethylenetriol.

[0030] The method for synthesizing polyoxyalkylene polymers is not particularly limited. Examples of synthesis methods for polyoxyalkylene polymers include polymerization using alkaline catalysts such as KOH, polymerization using transition metal compound-porphyrin complex catalysts such as the complex obtained by reacting an organoaluminum compound with porphyrin as shown in Japanese Patent Publication No. 61-215623, polymerization using complex metal cyanide complex catalysts as shown in Japanese Patent Publication No. 46-27250, Japanese Patent Publication No. 59-15336, U.S. Patent No. 3278457, U.S. Patent No. 3278458, U.S. Patent No. 3278459, U.S. Patent No. 3427256, U.S. Patent No. 3427334, and U.S. Patent No. 3427335, etc., polymerization using catalysts consisting of polyphosphazene salts as exemplified in Japanese Patent Publication No. 10-273512, and polymerization using catalysts consisting of phosphazene compounds as exemplified in Japanese Patent Publication No. 11-060722. Polymerization using complex metal cyanide catalysts is more preferable due to reasons such as lower manufacturing costs and the ability to obtain polymers with a narrow molecular weight distribution.

[0031] The main chain structure of polymer (A) may be a polyoxyalkylene polymer containing urethane bonds and other bonds other than ether bonds, such as urea bonds, to the extent that the desired effect is not significantly impaired. Specific examples of polymers having such a main chain structure include polyurethane prepolymers and polyurea prepolymers.

[0032] Polyurethane prepolymers can be obtained by known methods, such as reacting a polyol compound with a polyisocyanate compound. Polyurea prepolymers can be obtained by known methods, such as reacting a polyamine compound with a polyisocyanate compound. The main chain structure may be a prepolymer having a combination of urethane and urea bonds, obtained by reacting a polyol compound and a polyamine compound with a polyisocyanate compound.

[0033] Specific examples of polyol compounds include polyether polyols, polyester polyols, polycarbonate polyols, and polyether polyester polyols.

[0034] Specific examples of polyisocyanate compounds include diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, methylene-bis(cyclohexyl isocyanate), isophorone diisocyanate, and hexamethylene diisocyanate.

[0035] The ends of the polyurethane prepolymer may be either hydroxyl groups or isocyanate groups. The ends of the polyurea prepolymer may be either amino groups or isocyanate groups.

[0036] In curable compositions containing polymer (A) having one or more bonds selected from urethane bonds, urea bonds, and ester bonds in its main chain structure, the strength of the cured product may decrease due to cleavage of the urethane bonds, urea bonds, or ester bonds in the main chain structure caused by heat or other factors.

[0037] When polymers containing amide bonds in their main chain structure are used as organic polymers, the curability of the curable composition may be improved. For example, amide bonds can be represented as -NR. 4 It is represented as -C(=O)-. 4 This is an organic group that may have a hydrogen atom or a substituent. When the amount of amide bonds in the main chain structure is within an appropriate range, the viscosity of the polymer is low, and the decrease in strength of the cured product due to cleavage of amide bonds due to heat, etc., and the increase in viscosity of the curable composition due to storage are less likely to occur, resulting in good workability of the curable composition.

[0038] When polymer (A) contains amide bonds in its main chain structure, the number of amide bonds is preferably 1 to 10, more preferably 1.5 to 5, and even more preferably 2 to 3, on average per molecule. When the number of amide bonds on average per molecule is within this range, the curability of the curable composition is good, the viscosity of polymer (A) is low, and both polymer (A) and the curable composition are easy to handle.

[0039] Of the polymers (A) described above, polyoxyalkylene polymers that do not contain urethane bonds, urea bonds, ester bonds, or amide bonds in their main chain structure are most preferred, in terms of obtaining a curable composition with excellent storage stability and workability.

[0040] As polymer (A), a polymer obtained by introducing reactive silicon groups into the polymer by any of the following methods (a) to (d) is preferred. (a) After converting the terminal hydroxyl groups of the hydroxyl-terminated organic polymer to carbon-carbon unsaturated groups, the carbon-carbon unsaturated groups are converted to HSiR 1 a X 3-a A method of hydrosilylation using a hydrosilane represented by R. 1 X and a are the same as those in equation (1), respectively. (b) OCN-W-SiR 1 a X 3-aA method for reacting an isocyanate alkylsilane compound represented by . W is a divalent organic group. R 1 X and a are the same as those in equation (1), respectively. (c) After converting the terminal hydroxyl groups of the hydroxyl-terminated organic polymer to carbon-carbon unsaturated groups, the carbon-carbon unsaturated groups and HS-W-SiR 1 a X 3-a A method for carrying out an en-thiol reaction with a mercaptoalkylsilane compound represented by . W is a divalent organic group. R 1 X and a are the same as those in equation (1), respectively. (d) After synthesizing an NCO group-terminated organic polymer by reacting a hydroxyl group-terminated organic polymer with a polyisocyanate compound, the terminal NCO group is HNR 5 -W-SiR 1 a X 3-a , or HS-W-SiR 1 a X 3-a A method of reacting with a silane compound represented by . W is a divalent organic group. R 5 R is a hydrogen atom or an alkyl group. 1 X and a are the same as those in equation (1), respectively.

[0041] In the methods described in (a) and (c) above, examples of terminal carbon-carbon unsaturated groups include vinyl groups, allyl groups, methallyl groups, allenyl groups, and propargyl groups.

[0042] In any of the methods (b) to (d) above, the polymer (A) obtained using a silane compound in which W is methylene exhibits very high curability.

[0043] Method (a) is preferred because it is easy to obtain polymer (A) which has good storage stability. Methods (b), (c), and (d) are preferred because a high conversion rate can be obtained with a relatively short reaction time.

[0044] Methods for introducing reactive silicon groups by method (a) are proposed in the following publications: Japanese Patent Publication Nos. 45-36319, 46-12154, Japanese Patent Publication Nos. 50-156599, 54-6096, 55-13767, 55-13468, 57-164123, Japanese Patent Publication No. 3-2450, U.S. Patent No. 3632557, U.S. Patent No. 4345053, U.S. Patent No. 4366307, and U.S. Patent No. 4960844. Examples include the methods described, or the methods proposed in Japanese Patent Publication Nos. 61-197631, 61-215622, 61-215623, and 61-218632, which introduce reactive silicon groups to a high molecular weight polyoxypropylene polymer with a number average molecular weight of 6,000 or more, an Mw / Mn ratio of 1.6 or less, and a narrow molecular weight distribution, by hydrosilylation, etc., or the method proposed in Japanese Patent Publication No. 3-72527. Furthermore, as a method for introducing more than one reactive silicon group at the molecular end, the method proposed in Japanese Patent No. 6096320 can be cited.

[0045] The number-average molecular weight (Mn) of polymer (A) is not particularly limited. The number-average molecular weight of polymer (A) is preferably 5,000 to 30,000, and more preferably 6,000 to 25,000, as polystyrene-equivalent molecular weight in GPC. The weight-average molecular weight (Mw) of polymer (A), expressed as polystyrene-based molecular weight in GPC, is preferably 20,000 to 36,000, and more preferably 22,000 to 35,000. With respect to polymer (A), it is particularly preferable that the number-average molecular weight is 5,000 to 30,000 and the weight-average molecular weight is 20,000 to 36,000.

[0046] The molecular weight of polymer (A) can also be expressed as the end-group-reduced molecular weight, obtained by directly measuring the end-group concentration of the polymer precursor before the introduction of reactive silicon groups using titration analysis based on the principles of the hydroxyl value measurement method specified in JIS K 1557 and the iodine value measurement method specified in JIS K 0070, and considering the structure of the polymer (degree of branching determined by the polymerization initiator used). Alternatively, the end-group-reduced molecular weight of polymer (A) can be determined by creating a calibration curve between the number-average molecular weight obtained by general GPC measurement of the polymer precursor and the above-mentioned end-group-reduced molecular weight, and then converting the number-average molecular weight obtained by GPC of polymer (A) to the end-group-reduced molecular weight.

[0047] The molecular weight distribution (Mw / Mn) of polymer (A) is not particularly limited. A narrow molecular weight distribution of polymer (A) is preferred. Specifically, the molecular weight distribution is preferably 1.6 or less, more preferably 1.4 or less, even more preferably 1.3 or less, and particularly preferably 1.2 or less. The molecular weight distribution of polymer (A) can be determined from the number-average molecular weight and weight-average molecular weight obtained by GPC measurement.

[0048] To obtain a good rubber-like cured product, it is preferable that the reactive silicon groups of polymer (A) are present at the ends of the polymer chains. The number of reactive silicon groups is preferably 0.5 or more and 3.0 or less on average per polymer chain end, more preferably 0.6 or more and 2.5 or less, even more preferably 0.7 or more and 2.2 or less, and particularly preferably 0.8 or more and 2.0 or less. When the number of reactive silicon groups is 0.5 or more, the curability of polymer (A) and the curable composition is good, and the cured product of the curable composition has good rubber elasticity.

[0049] The number of reactive silicon groups in one molecule is preferably 1 to 7 on average, more preferably 1 to 4, and particularly preferably 1 to 3.

[0050] Furthermore, as described in Publication No. WO2013 / 180203, organic polymers having two or more reactive silicon groups at the ends of the polymer chains can also be used as polymer (A). Such polymers (A) exhibit high curability, and the resulting cured product can be expected to have high strength and high resilience.

[0051] Specific examples of commercially available polymer (A) products include Kaneka MS Polymer (registered trademark) and various reactive silicon group-containing polyoxypropylene products such as Kaneka Cyril (registered trademark). All of these commercially available polymers (A) are products of Kaneka Corporation. In addition, AGC Inc.'s Exester (registered trademark), WACKER's GENIOSIL (registered trademark), and RISUN POLYMER's STP can also be used.

[0052] <(meth)acrylic polymer (B)> (Meth)acrylic polymer (B) (hereinafter sometimes simply referred to as "polymer (B)") has reactive silicon groups. The reactive silicon group is not particularly limited as long as it can form a siloxane bond. The reactive silicon group represented by formula (1) above is preferred. Polymer (B) has a polymer skeleton and polymer chain ends bonded to the polymer skeleton. The polymer skeleton is a structure in which multiple structural units derived from monomers are continuously bonded. There may be one or more types of monomers.

[0053] Polymer chain ends are the parts located at the ends of polymer (B). The number of polymer chain ends in polymer (B) is 2 if the main chain structure is linear, and 3 or more if the polymer backbone is branched. If polymer (B) is a mixture of polymers with a linear main chain structure and polymers with a branched main chain structure, the number of polymer chain ends is, on average, between 2 and 3.

[0054] Reactive silicon groups can be present in the polymer backbone and at the polymer chain ends. Furthermore, two or more reactive silicon groups may be present at the polymer chain ends. When using a curable composition in adhesives, sealants, elastic coatings, or other adhesives, it is preferable that the reactive silicon groups in polymer (B) are present at the polymer chain ends.

[0055] The reactive silicon groups of polymer (B) may be the same as or different from the reactive silicon groups of polymer (A).

[0056] (Regarding the main chain structure of polymer (B)) Polymer (B) contains constituent units derived from (meth)acrylic acid ester. Furthermore, polymer (B) contains constituent units derived from (meth)acrylic acid ester having epoxy groups. The ratio of the weight of constituent units derived from epoxy group-containing (meth)acrylic acid ester to the weight of polymer (B) is 0.1 to 5% by weight, preferably 0.2 to 4% by weight, more preferably 0.3 to 3% by weight, even more preferably 0.4 to 2.5% by weight, and particularly preferably 0.5 to 2% by weight. In particular, if the ratio of the weight of constituent units derived from (meth)acrylic acid esters having epoxy groups to the weight of polymer (B) is 2.5% by weight or less, the curable composition is less likely to thicken when stored for a long period of time.

[0057] (Meth)acrylate alkyl ester means alkyl acrylate and / or alkyl methacrylate. Specific examples of alkyl acrylates include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-decyl acrylate, n-undecyl acrylate, lauryl acrylate, n-tridecyl acrylate, myristyl acrylate, cetyl acrylate, and stearyl acrylate, behenyl acrylate, and others.

[0058] Specific examples of alkyl methacrylates include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-decyl methacrylate, n-undecyl methacrylate, lauryl methacrylate, n-tridecyl methacrylate, myristyl methacrylate, cetyl methacrylate, stearyl methacrylate, and behenyl methacrylate.

[0059] The ratio of the total weight of constituent units derived from alkyl (meth)acrylate and the total weight of constituent units derived from epoxy group-containing (meth)acrylate to the weight of polymer (B) is preferably 50% by weight or more, more preferably 70% by weight or more, even more preferably 80% by weight or more, particularly preferably 90% by weight or more, and most preferably 100% by weight.

[0060] From the viewpoint of the compatibility of polymer (B) with polymer (A) and the stability of polymer (B), the alkyl (meth)acrylate ester used to prepare polymer (B) is preferably an alkyl (meth)acrylate ester having an alkyl group with 1 to 30 carbon atoms.

[0061] Alkyl (meth)acrylate esters having an alkyl group with 1 to 30 carbon atoms are defined by the following formula (B1): CH2=CR b1 COOR b2 (B1) (In formula (B1), R b1 R is a hydrogen atom or a methyl group. b2 (These are alkyl groups with 1 to 30 carbon atoms.) It is represented as follows.

[0062] In equation (B1), R b2 Examples include alkyl groups having 1 to 30 carbon atoms, such as methyl group, ethyl group, n-propyl group, n-butyl group, tert-butyl group, 2-ethylhexyl group, lauryl group, n-tridecyl group, cetyl group, and stearyl group. R b2 The number of carbon atoms in the alkyl group is more preferably 1 to 20.

[0063] Examples of (meth)acrylic acid esters having epoxy groups include aliphatic (meth)acrylic acid esters having linear aliphatic epoxy groups, alicyclic (meth)acrylates having alicyclic epoxy groups, and aromatic (meth)acrylic acid esters containing aromatic groups and having epoxy groups.

[0064] Examples of aliphatic (meth)acrylic acid esters having a linear aliphatic epoxy group include epoxyalkyl (meth)acrylates and epoxyalkyloxyalkyl (meth)acrylates, in which the linear aliphatic epoxy group is bonded to the oxy group (-O-) in the ester bond (-O-CO-).

[0065] The chain-like aliphatic epoxy group of such (meth)acrylic acid ester may contain one or more oxy groups (-O-) in the chain. The number of carbon atoms in the chain-like aliphatic epoxy group is not particularly limited, but is preferably 3 to 20, more preferably 3 to 15, and particularly preferably 3 to 10.

[0066] Specific examples of the above aliphatic (meth)acrylic acid esters include epoxyalkyl (meth)acrylates such as glycidyl (meth)acrylate, 2-methylglycidyl (meth)acrylate, 3,4-epoxybutyl (meth)acrylate, and 6,7-epoxyheptyl (meth)acrylate; epoxyalkyloxyalkyl (meth)acrylates such as 2-glycidyloxyethyl (meth)acrylate, 3-glycidyloxy-n-propyl (meth)acrylate, 4-glycidyloxy-n-butyl (meth)acrylate, 5-glycidyloxy-n-hexyl (meth)acrylate, and 6-glycidyloxy-n-hexyl (meth)acrylate; (3,4-epoxycyclohexyl)(meth)acrylate, 3,4-epoxy-6-methylcyclohexylmethyl (meth)acrylate, and 3,4-epoxytricyclo[5.2.1.0 2,6 Examples include alicyclic (meth)acrylates such as decane-8-(or 9-)yl(meth)acrylate.

[0067] Specific examples of the aromatic (meth)acrylic acid esters mentioned above include 4-glycidyloxyphenyl (meth)acrylate, 3-glycidyloxyphenyl (meth)acrylate, 2-glycidyloxyphenyl (meth)acrylate, 4-glycidyloxyphenyl methyl (meth)acrylate, 3-glycidyloxyphenyl methyl (meth)acrylate, and 2-glycidyloxyphenyl methyl (meth)acrylate.

[0068] The monomers for producing polymer (B) may include alkyl (meth)acrylates and other monomers other than (meth)acrylates having epoxy groups. Other monomers include acrylic acid and methacrylic acid; (meth)acrylamides such as acrylamide, methacrylamide, N-methylolacrylamide, and N-methylolmethacrylamide; amino group-containing unsaturated compounds such as 2-(N,N-diethylamino)ethyl methacrylate and 2-aminoethyl vinyl ether; acrylonitrile and methacrylonitrile; styrenes such as styrene and α-methylstyrene; alkyl vinyl ethers; vinyl chloride; fatty acid vinyl esters such as vinyl acetate and vinyl propionate.

[0069] The number-average molecular weight (Mn) of polymer (B) is not particularly limited. The number-average molecular weight of polymer (B) is preferably 3,000 to 60,000, and more preferably 4,000 to 50,000, as polystyrene-equivalent molecular weight in GPC. The weight-average molecular weight (Mw) of polymer (B) is preferably 6,000 to 180,000, and more preferably 7,000 to 160,000, as the polystyrene-based molecular weight in GPC. With respect to polymer (B), it is particularly preferable that the number-average molecular weight is 3,000 to 60,000 and the weight-average molecular weight is 6,000 to 180,000.

[0070] The molecular weight distribution (Mw / Mn) of polymer (B) is not particularly limited. A narrow molecular weight distribution of polymer (B) is preferred. Specifically, the molecular weight distribution is preferably 1.6 or less, more preferably 1.4 or less, even more preferably 1.3 or less, and particularly preferably 1.2 or less. The molecular weight distribution of polymer (B) can be determined from the number-average molecular weight and weight-average molecular weight obtained by GPC measurement.

[0071] Polymer (B) can be produced by conventional vinyl polymerization methods. Examples of vinyl polymerization methods include solution polymerization by radical reaction and bulk polymerization. However, vinyl polymerization methods are not limited to these methods. The polymerization reaction described above is typically carried out at 50-150°C in the presence of monomers, radical initiators, chain transfer agents, and solvents. The conditions for the polymerization reaction are not limited to those described above.

[0072] Specific examples of radical initiators include azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), and benzoyl peroxide. Specific examples of chain transfer agents include mercaptans such as n-dodecyl mercaptan, tert-dodecyl mercaptan, and lauryl mercaptan, as well as halogen-containing compounds. As solvents, solvents that are inert to polymerization reactions, such as ethers, hydrocarbons, and esters, can preferably be used.

[0073] Various methods are known for introducing reactive silicon groups into (meth)acrylic polymers. For example, I) A method for copolymerizing a compound having an ethylenically unsaturated double bond and a reactive silicon group with an alkyl (meth)acrylate represented by formula (B1); II) A copolymer obtained by copolymerizing a compound having an ethylenically unsaturated double bond and a reactive functional group (e.g., acrylic acid) with an alkyl (meth)acrylate represented by formula (B1), wherein the reactive functional group is reacted with reactive silicon and a compound capable of reacting with the reactive group (e.g., a reactive silicon group-containing isocyanate compound); III) A method for polymerizing an alkyl (meth)acrylate represented by formula (B1) in the presence of a mercaptan having a reactive silicon group as a chain transfer agent; VI) A method for polymerizing an alkyl (meth)acrylate represented by formula (B1) using an azobisnitrile compound having a reactive silicon group or a disulfide compound having a reactive silicon group as an initiator; and V) A method is used in which a reactive silicon group is introduced at the end of the molecular chain in a polymer obtained by polymerizing an alkyl (meth)acrylate represented by formula (B1) using a living radical polymerization method. The method for introducing reactive silicon groups into (meth)acrylic polymers is not limited to the method described above.

[0074] The compound having an ethylenically unsaturated double bond and a reactive silicon group used in the method described in I) above is the following formula (B2): CH2=CR b5 COOR b6 -SiR 1 a X 3-a (B2) (In formula (B2), R 1 , X, and a are R in equation (1) 1 , X, and a are the same. R b5 R is a hydrogen atom or a methyl group. b6 (This refers to an alkylene group with 1 to 6 carbon atoms.) Compounds represented by are preferred.

[0075] In equation (B2), R b6 The alkylene group is an alkylene group having 1 to 6 carbon atoms, such as a methylene group, an ethane-1,2-diyl group (ethylene group), and a propane-1,3-diyl group (trimethylene group), and preferably an alkylene group having 1 to 4 carbon atoms.

[0076] Specific examples of compounds having an ethylenically unsaturated double bond and a reactive silicon group include γ-methacryloxypropyl alkoxysilanes such as γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, and γ-methacryloxypropyltriethoxysilane; γ-acryloxypropyl alkoxysilanes such as γ-acryloxypropyltrimethoxysilane, γ-acryloxypropylmethyldimethoxysilane, and γ-acryloxypropyltriethoxysilane; and vinyl alkoxysilanes such as vinyltrimethoxysilane, vinylmethyldimethoxysilane, and vinyltriethoxysilane.

[0077] Examples of reactive functional groups in compounds having an ethylenically unsaturated double bond and a reactive functional group used in method II) above include amino groups, hydroxyl groups, and carboxyl groups. Examples of groups that can react with these reactive functional groups include isocyanate groups. Furthermore, as described in other publications such as Japanese Patent Publication No. 54-36395, Japanese Patent Publication No. 01-272654, and Japanese Patent Publication No. 02-214759, allyl groups can be used as reactive functional groups. Silicon hydride (H-Si) groups can react with allyl groups.

[0078] Examples of mercaptans containing reactive silicon groups as chain transfer agents used in method III) above include γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, and γ-mercaptopropyltriethoxysilane.

[0079] Examples of azobisnitrile compounds and disulfide compounds having a reactive silicon group used in the method described in IV) above include azobisnitrile compounds having an alkoxysilyl group and disulfide compounds having an alkoxysilyl group as described in Japanese Patent Publication No. 60-23405 and Japanese Patent Publication No. 62-70405, etc.

[0080] An example of the method described in (V) above is the method described in Japanese Patent Publication No. 09-272714, etc.

[0081] Other methods include those described in Japanese Patent Publication No. 59-168014 and Japanese Patent Publication No. 60-228516, which involve the combined use of a mercaptan having a reactive silicon group and a radical polymerization initiator having a reactive silicon group.

[0082] The number of reactive silicon groups in polymer (B) is not particularly limited. Preferably, polymer (B) has an average of 0.1 to 2.0 reactive silicon groups per molecule, and more preferably 0.5 to 1.5 reactive silicon groups.

[0083] The amount of polymer (B) used in the curable composition is not particularly limited, as long as the desired effect is not impaired. In a curable composition, the weight W of the polyoxyalkylene polymer (A) A And the weight W of (meth)acrylic polymer (B) B The ratio W A / W B However, 95 / 5 to 5 / 95 is preferred, 90 / 10 to 20 / 80 is more preferred, and 80 / 20 to 50 / 50 is even more preferred.

[0084] It is common practice among those skilled in the art to select the monomer composition of polymer (B) according to the application and purpose of the curable composition. When a curable composition is used in applications requiring strength, such as adhesives, it is preferable that the glass transition temperature (Tg) of polymer (B) is relatively high. Specifically, the Tg of the (meth)acrylic acid ester polymer (B) is preferably 0 to 200°C, and more preferably 20 to 100°C. The Tg can be determined from the following Fox formula.

[0085] Fox's formula: 1 / (Tg(K))=Σ(Mi / Tgi) (In the formula, Mi is the weight fraction of monomer i that constitutes the polymer, and Tgi is the glass transition temperature (K) of the homopolymer of monomer i.)

[0086] For example, polymethyl methacrylate is known as a (meth)acrylic polymer with a relatively high glass transition temperature (Tg). Therefore, in the monomer used to produce polymer (B), the larger the ratio of methyl methacrylate to the weight of the monomer, the higher the glass transition temperature (Tg) of polymer (B) tends to be. Conversely, the smaller the ratio of methyl methacrylate to the weight of the monomer, the lower the glass transition temperature (Tg) of polymer (B) tends to be. When the curable composition is used as an adhesive, it is preferable that the weight ratio of methyl methacrylate to the weight of the monomer used in the production of polymer (B) is 50% or more, as this facilitates the formation of a high-strength cured product. When the curable composition is used as a sealant, it is preferable that the weight ratio of methyl methacrylate to the weight of the monomer used in the production of polymer (B) is less than 50%, as this results in a low viscosity and good workability of the curable composition.

[0087] <Polyfunctional Thiol (C)> The curable composition contains a polyfunctional thiol (C). The polyfunctional thiol reacts with the epoxy groups of the polymer (B) to accelerate the curing of the curable composition.

[0088] As the polyfunctional thiol (C), any polyfunctional thiol compound that has been conventionally used as a curing agent for epoxy compounds can be used without any particular restrictions. As the polyfunctional thiol (C), a compound having two or more thiol groups in one molecule is preferred in terms of reactivity with the polymer (B). The thiol groups of the polyfunctional thiol (C) may be primary, secondary, or tertiary thiol groups. The polyfunctional thiol (C) may have a combination of two or more groups selected from primary, secondary, and tertiary thiol groups. It is preferable that the polyfunctional thiol (C) is a compound having a secondary thiol group.

[0089] Preferred examples of polyfunctional thiols (C) include trimethylolpropane tri(3-mercaptopropionate), pentaerythritol tetra(3-mercaptopropionate), dipentaerythritol hexa(3-mercaptopropionate), tris-[2-(3-mercaptopropionyloxy)ethyl]isocyanurate, tetraethylene glycol di(3-mercaptopropionate), trimethylolpropane di(3-mercaptopropyl) ether, and pentaerythritol tri(3-mercaptopropyl) ether. Examples include polyfunctional thiols having primary thiol groups such as tel and pentaerythritol tetra(3-mercaptopropyl) ether; and polyfunctional thiols having secondary thiol groups such as pentaerythritol tetra(3-mercaptobutyrate), 1,4-butanediol bis(3-mercaptobutyrate), 1,3,5-tris[2-(3-mercaptobutanoyloxy)ethyl]-1,3,5-triazine-2,4,6(1H,3H,5H)trione, and trimethylolpropanetri(3-mercaptobutyrate).

[0090] Among these, pentaerythritol tetra(3-mercaptobutyrate), 1,4-butanediol bis(3-mercaptobutyrate), 1,3,5-tris[2-(3-mercaptobutanoyloxy)ethyl]-1,3,5-triazine-2,4,6(1H,3H,5H)trione, and trimethylolpropane tri(3-mercaptobutyrate) are preferred.

[0091] The polyfunctional thiol (C) may be used alone or in combination of two or more types.

[0092] The amount of polyfunctional thiol (C) is preferably 0.01 to 20 parts by weight, more preferably 0.03 to 10 parts by weight, even more preferably 0.05 to 5 parts by weight, and particularly preferably 0.1 to 2 parts by weight, based on 100 parts by weight of the total weight of polyoxyalkylene polymer (A) and (meth)acrylic polymer (B).

[0093] <Curing catalyst (D)> The curable composition contains a curing catalyst (D) for the purpose of promoting the hydrolysis condensation reaction between the reactive silicon groups of polymer (A) and polymer (B), thereby extending or crosslinking the polymer chains. Examples of curing catalysts (D) include organotin compounds, metal carboxylate salts, amine compounds, carboxylic acids, and alkoxy metals. Furthermore, when a compound corresponding to a tertiary amine (E), described later, is used as the curing catalyst (D), the tertiary amine possesses both the function of a tertiary amine (E) and the function of a curing catalyst (D).

[0094] Specific examples of organotin compounds include dibutyltin dilaurate, dibutyltin dioctanoate, dibutyltin bis(butylmaleate), dibutyltin diacetate, dibutyltin oxide, dibutyltin diacetylacetonate, dioctyltin diacetylacetonate, dioctyltin dilaurate, dioctyltin distearate, dioctyltin diacetate, dioctyltin oxide, reaction products of dibutyltin oxide and silicate compounds, reaction products of dioctyltin oxide and silicate compounds, and reaction products of dibutyltin oxide and phthalate esters.

[0095] Specific examples of metal carboxylate salts include tin carboxylate, bismuth carboxylate, titanium carboxylate, zirconium carboxylate, and iron carboxylate. Furthermore, salts combining the following carboxylic acids with various metals can be used as metal carboxylate salts.

[0096] Specific examples of amine compounds include amines such as octylamine, 2-ethylhexylamine, laurylamine, and stearylamine; nitrogen-containing heterocyclic compounds such as pyridine, 1,8-diazabicyclo[5,4,0]undecene-7 (DBU), and 1,5-diazabicyclo[4,3,0]nonene-5 (DBN); guanidines such as guanidine, phenylguanidine, and diphenylguanidine; biguanides such as butyl biguanide, 1-o-tolylbiguanide, and 1-phenylbiguanide; amino group-containing silane coupling agents; and ketimine compounds.

[0097] Specific examples of carboxylic acids include acetic acid, propionic acid, butyric acid, 2-ethylhexanoic acid, lauric acid, stearic acid, oleic acid, linoleic acid, neodecanoic acid, and versatic acid.

[0098] Specific examples of alkoxy metals include titanium compounds such as tetrabutyl titanate, titanium tetrakis (acetylacetonate), and diisopropoxytitanium bis (ethylacetoacetate), as well as aluminum compounds such as aluminum tris (acetylacetonate) and diisopropoxyaluminum ethylacetoacetate, and zirconium compounds such as zirconium tetrakis (acetylacetonate). Other silanol condensation catalysts that can be used include fluorine anion-containing compounds, photoacid generators, and photobase generators. The curing catalyst (D) may be used in combination with two or more different catalysts. The amount of curing catalyst (D) used is preferably 0.001 to 20 parts by weight, more preferably 0.01 to 15 parts by weight, and particularly preferably 0.01 to 10 parts by weight, based on 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

[0099] <Tertiary amine (E)> The curable composition may contain a tertiary amine (E). The tertiary amine (E) accelerates the curing of the curable composition.

[0100] Tertiary amines (E) are compounds that have a tertiary amino group in which three carbon atoms are bonded to a nitrogen atom. The number of tertiary amino groups in one molecule of tertiary amine (E) is preferably two or more, and more preferably three or more. The tertiary amine (E) may have a combination of a tertiary amino group, a primary amino group, and / or a secondary amino group. In the specification and claims of this application, compounds having a combination of a tertiary amino group, a primary amino group, and / or a secondary amino group are conveniently defined as "tertiary amines."

[0101] Suitable examples of tertiary amines (E) include chain-like aliphatic tertiary amines such as triethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-octylamine, N,N-dimethylethylenediamine, N,N,N',N'-tetramethylethylenediamine, polyethyleneimine, and triethanolamine; N-methylmorpholine, N-ethylmorpholine, N-methylpiperidine, N-ethylpiperidine, N-methylpiperazine, N,N'-ethylpiperazine, N,N'-dimethylpiperazine, N,N'-diethylpiperazine, 1,8-diazabicyclo(5,4, Examples include alicyclic tertiary amines such as 0)-undecene-7 (DBU), 1,5-diazabicyclo(4,3,0)-nonene-5 (DBN), and 1,4-diazabicyclo[2.2.2]octane (DABCO); and aromatic group-containing tertiary amines such as methyldiphenylamine, ethyldiphenylamine, dimethylphenylamine (N,N-dimethylaniline), diethylphenylamine (N,N-diethylaniline), triphenylamine, methyldibenzylamine, ethyldibenzylamine, dimethylbenzylamine, diethylbenzylamine, tripenzylamine, 4-dimethylaminopyridine, and 2,4,6-tri(dimethylaminomethyl)phenol.

[0102] The amount of tertiary amine (E) is preferably 0.01 to 10 parts by weight, more preferably 0.01 to 5 parts by weight, and even more preferably 0.01 to 2 parts by weight, based on 100 parts by weight of the total weight of polyoxyalkylene polymer (A) and (meth)acrylic polymer (B).

[0103] <Other additives> The curable composition may contain other additives besides polymer (A), polymer (B), polyfunctional thiol (C), curing catalyst (D), and tertiary amine (E), to the extent that the desired effect is not impaired. Examples of other additives include curing catalysts, fillers, adhesion promoters, plasticizers, solvents, diluents, thixotropic agents, antioxidants, light stabilizers, UV absorbers, property modifiers, tackifying resins, compounds containing epoxy groups, photocurable substances, oxygen-curable substances, epoxy resins, other resins, surface modifiers, foaming agents, curing modifiers, flame retardants, silicates, radical inhibitors, metal deactivators, phosphorus-based peroxide decomposers, lubricants, pigments, and antifungal agents.

[0104] (Filler) Various fillers may be added to the curable composition. Examples of fillers include reinforcing fillers such as fumed silica, precipitated silica, crystalline silica, fused silica, dolomite, anhydrous silicic acid, hydrated silicic acid, and carbon black; fillers such as heavy calcium carbonate, colloidal calcium carbonate, magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium dioxide, bentonite, organic bentonite, ferric oxide, aluminum powder, flint powder, zinc oxide, activated zinc oxide, and resin powder; and fibrous fillers such as asbestos, glass fibers, and filaments. Examples of resin powders include PVC powder and PMMA powder. When using a filler, the amount of filler used is preferably 1 to 300 parts by weight, and more preferably 10 to 200 parts by weight, per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

[0105] When a hardened product with high strength is desired using these fillers, fillers selected from fumed silica, precipitated silica, crystalline silica, fused silica, dolomite, anhydrous silicic acid, hydrated silicic acid, carbon black, surface-treated fine calcium carbonate, calcined clay, clay, and activated zinc oxide are preferably used. In terms of the strength of the cured product, the preferred amount of these fillers to use is 1 to 200 parts by weight per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B). Furthermore, if it is desired to obtain a cured product with low strength and high elongation at break, fillers selected mainly from titanium dioxide, calcium carbonate, magnesium carbonate, talc, ferric oxide, zinc oxide, and shirasu balloons can be preferably used. In terms of the elongation at break of the cured product, the preferred amount of these fillers to use is 5 to 200 parts by weight per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

[0106] Generally, the larger the specific surface area of ​​calcium carbonate, the greater the improvement in the fracture strength, elongation at fracture, and adhesion of the cured product. These fillers may be used individually or in mixtures of two or more types. Fatty acid surface-treated colloidal calcium carbonate and untreated heavy calcium carbonate or other calcium carbonate with a particle size of 1 μm or larger can be used in combination.

[0107] The curable composition may contain spherical hollow bodies, such as balloons, for the purpose of reducing the weight (specific gravity) of the cured product. A balloon is a hollow, spherical filler. Examples of balloon materials include inorganic materials such as glass, shirasu (volcanic ash), and silica, and organic materials such as phenolic resin, urea resin, polystyrene, saran, and acrylonitrile. However, the balloon material is not limited to these materials. The balloon material may be a composite material consisting of inorganic and organic materials. Furthermore, the balloon material may consist of multiple layers laminated together. In addition, a single type of balloon may be used, or two or more types may be used in combination. The surface of the balloon may be surface-treated, coated, or treated with various surface treatment agents. For example, organic balloons coated with calcium carbonate, talc, titanium dioxide, etc., or inorganic balloons surface-treated with silane coupling agents can be used.

[0108] The balloon particle size is preferably 3 μm to 200 μm, and particularly preferably 10 μm to 110 μm. When the balloon particle size is within the above range, the cured product can be made lighter to the desired extent by using an appropriate amount of balloons, and the cured product can be formed while suppressing the occurrence of surface irregularities and a decrease in elongation.

[0109] When using balloons, slip-preventing agents such as those described in Japanese Patent Publication No. 2000-154368 and amine compounds that create an uneven and matte surface on the cured product, as described in Japanese Patent Publication No. 2001-164237, can be added to the curable composition. Among the aforementioned amine compounds, primary and / or secondary amines with a melting point of 35°C or higher are particularly preferred.

[0110] Specific examples of balloons are described in Japanese Patent Publication Nos. Hei 2-129262, Hei 4-8788, Hei 4-173867, Hei 5-1225, Hei 7-113073, Hei 9-53063, Hei 10-251618, Hei 2000-154368, Hei 2001-164237, WO97 / 05201, and others.

[0111] The amount of spherical hollow bodies (balloons) used is preferably 0.01 to 30 parts by weight per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B). The lower limit is more preferably 0.1 parts by weight, and the upper limit is more preferably 20 parts by weight. Using an amount of spherical hollow bodies within the above range results in a good curable composition and makes it easy to form a cured product with excellent elongation and tensile strength.

[0112] (Adhesion-enhancing agent) The curable composition may contain an adhesion promoter. An example of an adhesion promoter is a silane coupling agent. Silane coupling agents are compounds having a hydrolyzable silicon group and a functional group other than a hydrolyzable silicon group in their molecule. When a curable composition is applied to various substrates, such as inorganic substrates like glass, aluminum, stainless steel, zinc, copper, and mortar, and organic substrates like vinyl chloride, acrylic, polyester, polyethylene, polypropylene, and polycarbonate, a significant improvement in adhesion is observed under non-primer conditions or primer-treated conditions. The effect of improving adhesion to various substrates is particularly pronounced when the curable composition is used under non-primer conditions. In addition to the above functions, silane coupling agents can also function as dehydrating agents, property modifiers, and dispersibility modifiers for inorganic fillers.

[0113] The hydrolyzable groups in the hydrolyzable silicon groups of the silane coupling agent are not particularly limited. Examples of hydrolyzable groups include hydrogen atoms, halogen atoms, alkoxy groups, aryloxy groups, alkenyloxy groups, acyloxy groups, ketoximate groups, amino groups, amide groups, acid amide groups, aminooxy groups, and mercapto groups. Among these, halogen atoms, alkoxy groups, alkenyloxy groups, and aryloxy groups are preferred due to their high activity. Chlorine atoms and alkoxy groups are preferred because they are easily introduced into the silane coupling agent. Alkoxy groups such as methoxy groups and ethoxy groups are more preferred, with methoxy groups and ethoxy groups being particularly preferred, due to their mild hydrolysis and ease of handling. Furthermore, ethoxy groups and isopropenyloxy groups are preferred in terms of safety because the compounds eliminated by the reaction are ethanol and acetone, respectively. The number of hydrolyzable groups bonded to the silicon atoms in the silane coupling agent may be preferably three to ensure good adhesion. Alternatively, two may be preferable to ensure the storage stability of the curable composition.

[0114] When using a silane coupling agent as an adhesion promoter, an aminosilane coupling agent having a hydrolyzable silicon group and a substituted or unsubstituted amino group is preferred because it has a greater adhesion-improving effect. The substituent on the substituted amino group is not particularly limited. Examples of such substituents include alkyl groups, aralkyl groups, and aryl groups.

[0115] Specific examples of aminosilane coupling agents include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltriisopropoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethylamino)propylmethyldimethoxysilane, 3-(2-aminoethylamino)propyltriethoxysilane, 3-(2-aminoethylamino)propylmethyldiethoxysilane, 3-(2-aminoethylamino)propyltriisopropoxysilane, 3-(2-(2-aminoethylamino)ethylamino)propyltrimethoxysilane, 3-(6-aminohexylamino)propyltrimethoxysilane, and 3-ethylamino-2-methylpropyltrimethoxysilane. Examples of amino group-containing silanes include 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-benzylaminopropyltrimethoxysilane, 3-(vinylbenzylamino)propyltriethoxysilane, N-cyclohexylaminomethyltriethoxysilane, N-cyclohexylaminomethyldiethoxymethylsilane, N-phenylaminomethyltrimethoxysilane, N-butylaminopropyltrimethoxysilane, (2-aminoethylamino)methyltrimethoxysilane, N,N'-bis[3-(trimethoxysilyl)propyl]ethylenediamine, and bis(trimethoxysilylpropyl)amine; and ketimine-type silanes such as N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propanamine.

[0116] Of these, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, and 3-(2-aminoethylamino)propylmethyldimethoxysilane are preferred in terms of good adhesion of the cured product. One aminosilane coupling agent may be used, or two or more may be used in combination. It has been noted that 3-(2-aminoethylamino)propyltrimethoxysilane is more irritating than other aminosilanes. Irritation can be mitigated by reducing the amount of 3-(2-aminoethylamino)propyltrimethoxysilane and using 3-aminopropyltrimethoxysilane in combination. Furthermore, silane coupling agents oligomerized by partially condensing hydrolyzable silicon groups can also be suitably used in terms of safety and stability. The silane coupling agents to be condensed may be a single agent or multiple agents. Examples of oligomerized silane coupling agents include Dynasylan 1146 from Evonik. In terms of good storage stability of the curable composition, 3-aminopropyltrimethoxysilane and 3-(2-aminoethylamino)propylmethyldimethoxysilane are preferred.

[0117] Specific examples of silane coupling agents other than aminosilane coupling agents include epoxy group-containing silane coupling agents such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane; isocyanate group-containing silane coupling agents such as 3-isocyanatetopropyltrimethoxysilane, 3-isocyanatetopropyltriethoxysilane, 3-isocyanatetopropylmethyldiethoxysilane, 3-isocyanatetopropylmethyldimethoxysilane, (isocyanatemethyl)trimethoxysilane, and (isocyanatemethyl)dimethoxymethylsilane; and 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane. Examples include mercapto group-containing silane coupling agents such as 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, and mercaptomethyltriethoxysilane; carboxysilane coupling agents such as 2-carboxyethyltriethoxysilane, 2-carboxyethylphenylbis(2-methoxyethoxy)silane, and N-2-(carboxymethylamino)ethyl-3-aminopropyltrimethoxysilane; vinyl-type unsaturated group-containing silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, and 3-acryloyloxypropylmethyltriethoxysilane; halogen-containing silane coupling agents such as 3-chloropropyltrimethoxysilane; and isocyanurate silane coupling agents such as tris(trimethoxysilyl)isocyanurate. In addition, condensates obtained by partially condensing the above silane coupling agents can also be used. Examples of such condensates include Dynasylan6490 and Dynasylan6498 from Evonik.Furthermore, modified derivatives of these, such as amino-modified silyl polymers, silylated amino polymers, unsaturated aminosilane complexes, phenylamino long-chain alkylsilanes, aminosilylated silicones, and silylated polyesters, can also be used as silane coupling agents.

[0118] Of these, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, and 3-glycidoxypropylmethyldimethoxysilane are preferred in terms of good adhesion of the cured product.

[0119] The above silane coupling agents may be used individually or in combination of two or more types. The amount of silane coupling agent used is preferably 0.1 to 20 parts by weight, and more preferably 0.5 to 10 parts by weight, per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

[0120] (Plasticizer) The curable composition may contain a plasticizer. By adding a plasticizer, the viscosity and slump of the curable composition, as well as mechanical properties such as the tensile strength and elongation of the cured product, can be adjusted.

[0121] Specific examples of plasticizers include phthalate ester compounds such as dibutyl phthalate, diisononyl phthalate (DINP), diheptyl phthalate, di(2-ethylhexyl) phthalate, diisodecyl phthalate (DIDP), and butyl benzyl phthalate; terephthalate ester compounds such as bis(2-ethylhexyl)-1,4-benzenedicarboxylate; hydrogenated phthalate compounds such as 1,2-cyclohexanedicarboxylic acid diisononyl ester; dioctyl adipate, dioctyl sebacate, dibutyl sebacate, and disuccinate. Examples include aliphatic polycarboxylic acid ester compounds such as isodecyl and tributyl acetylcitrate; unsaturated fatty acid ester compounds such as butyl oleate and methyl acetylricinoleate; alkyl sulfonate phenyl esters; phosphate ester compounds such as tricresyl phosphate and tributyl phosphate; trimellitic acid ester compounds; chlorinated paraffin; hydrocarbon oils such as alkyldiphenyl and partially hydrogenated terphenyl; process oils; epoxy plasticizers such as epoxidized soybean oil and benzyl epoxy stearate. A specific example of a terephthalate ester compound is EASTMAN 168 (trade name, manufactured by EASTMAN CHEMICAL). A specific example of a non-phthalate ester compound is Hexamoll DINCH (trade name, manufactured by BASF). A specific example of an alkylsulfonate phenyl ester is Mesamoll (trade name, manufactured by LANXESS).

[0122] High molecular weight plasticizers can also be used. Using high molecular weight plasticizers allows the initial properties of the cured product to be maintained over a longer period compared to using low molecular weight plasticizers. Furthermore, the drying properties (coatability) when alkyd paint is applied to the cured product are improved.

[0123] Specific examples of polymeric plasticizers include vinyl polymers, which are polymers of vinyl monomers; esters of polyalkylene glycols and polyols such as diethylene glycol dibenzoate, triethylene glycol dibenzoate, and pentaerythritol ester; polyester plasticizers obtained from dibasic acids such as sebacic acid, adipic acid, azelaic acid, and phthalic acid, and dihydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, and dipropylene glycol; polyether polyols (polyoxyalkylene compounds) such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol with a number average molecular weight of 500 or more, and even 1,000 or more; derivatives of these polyether polyols obtained by converting the hydroxyl groups to ester groups, ether groups, etc.; polystyrenes such as polystyrene and poly-α-methylstyrene; and polybutadiene, polybutene, polyisobutylene, butadiene-acrylonitrile, and polychloroprene. Polymeric plasticizers are not limited to these.

[0124] The polymeric plasticizer is preferably compatible with polyoxyalkylene polymers (A) and / or (meth)acrylic polymers (B). From this point of view, polyethers and vinyl polymers are preferred. When polyethers are used as plasticizers, surface curability and deep curability are improved, and curing delay after storage does not occur. Among polyethers, polypropylene glycol is more preferred. Vinyl polymers are also preferred in terms of compatibility with polyoxyalkylene polymers (A) and / or (meth)acrylic polymers (B), as well as the weather resistance and heat resistance of the cured product. Among vinyl polymers, acrylic polymers and / or methacrylic polymers are preferred, and acrylic polymers such as alkyl polyacrylates are even more preferred. As for the synthesis method of vinyl polymers, living radical polymerization is preferred, and atom transfer radical polymerization is even more preferred, as it yields polymers with a narrow molecular weight distribution and low viscosity. Furthermore, the so-called SGO process, described in Japanese Patent Publication No. 2001-207157, which involves continuous bulk polymerization of alkyl acrylate monomers at high temperature and high pressure, is also a preferred method for producing vinyl polymers.

[0125] The number-average molecular weight of the polymeric plasticizer is preferably 500 to 15,000, more preferably 800 to 10,000, even more preferably 1,000 to 8,000, particularly preferably 1,000 to 5,000, and most preferably 1,000 to 3,000. When the number-average molecular weight of the polymeric plasticizer is within the above range, the leaching of the plasticizer from the cured product over time due to heat, rainfall, etc., can be suppressed, the initial physical properties of the cured product can be maintained for a long period of time, the curable composition has an appropriate viscosity, and the curable composition has good workability. The molecular weight distribution of the polymeric plasticizer is not particularly limited, but a narrow distribution is preferred. Specifically, the molecular weight distribution is preferably less than 1.80, more preferably 1.70 or less, even more preferably 1.60 or less, still more preferably 1.50 or less, particularly preferably 1.40 or less, and most preferably 1.30 or less.

[0126] The number-average molecular weight of vinyl polymers is measured by GPC (Geomorphic Spectroscopy). The number-average molecular weight of polyether polymers is measured by end-group analysis. Furthermore, the molecular weight distribution (Mw / Mn) is measured by GPC (polystyrene equivalent).

[0127] The polymeric plasticizer may or may not have reactive silicon groups. If the polymeric plasticizer has reactive silicon groups, it acts as a reactive plasticizer, preventing the migration of the plasticizer from the cured product. When the polymeric plasticizer has reactive silicon groups, the number of reactive silicon groups is preferably one or less on average per molecule, and more preferably 0.8 or less. When using a plasticizer having reactive silicon groups, particularly a polyether polymer having reactive silicon groups, its number-average molecular weight must be lower than the number-average molecular weight of the polyoxyalkylene polymer (A) and / or the (meth)acrylic polymer (B).

[0128] Among the plasticizers described above, at least one selected from the group consisting of phthalate esters, hydrogenated phthalate esters, and polyoxyalkylene compounds is preferred.

[0129] The amount of plasticizer used is preferably 5 to 150 parts by weight, more preferably 10 to 120 parts by weight, and even more preferably 20 to 100 parts by weight, per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B). When the amount of plasticizer used is within the above range, it is possible to form a cured product with excellent mechanical strength while fully obtaining the desired effect of using the plasticizer. The plasticizer may be used alone or in combination of two or more types. A low molecular weight plasticizer and a high molecular weight plasticizer may be used in combination. These plasticizers may be blended into the polyoxyalkylene polymer (A) or the (meth)acrylic polymer (B) when producing the polyoxyalkylene polymer (A) or the (meth)acrylic polymer (B).

[0130] (Solvents, diluents) The curable composition may contain a solvent or a diluent. The solvent and diluent are not particularly limited. Examples of solvents and diluents include aliphatic hydrocarbons, aromatic hydrocarbons, alicyclic hydrocarbons, halogenated hydrocarbons, alcohols, esters, ketones, and ethers. When using a solvent or diluent, to address the issue of air pollution when the curable composition is used indoors, the boiling point of the solvent is preferably 150°C or higher, more preferably 200°C or higher, and particularly preferably 250°C or higher. The solvent or diluent may be used alone or in combination of two or more.

[0131] (Tixotropic agent) The curable composition may contain a thixotropic agent as needed to prevent sagging and improve workability. The thixotropic agent is not particularly limited. Examples of thixotropic agents include polyamide waxes and hydrogenated castor oil derivatives. These thixotropic agents may be used alone or in combination of two or more. The amount of thixotropic agent used is preferably 0.1 to 20 parts by weight per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

[0132] (Antioxidant) The curable composition may contain an antioxidant (anti-aging agent). Using an antioxidant can improve the weather resistance of the cured product. Examples of antioxidants include hindered phenol compounds, monophenol compounds, bisphenol compounds, and polyphenol compounds. For example, Irganox 245, Irganox 1010, Irganox 1035, Irganox 1076, Irganox 1135, Irganox 1330, and Irganox 1520 (all manufactured by BASF); SONGNOX 1076 (manufactured by SONGWON); and BHT are examples of suitable antioxidants. Similarly, hindered amine-based light stabilizers such as Chinuvin 622LD, Chinuvin 144, Chinuvin 292, CHIMASSORB944LD, and CHIMASSORB119FL (all manufactured by BASF); Adekastab LA-57, Adekastab LA-62, Adekastab LA-67, Adekastab LA-63, and Adekastab LA-68 (all manufactured by ADEKA Corporation); Sanol LS-2626, Sanol LS-1114, and Sanol LS-744 (all manufactured by Sankyo Life Tech Co., Ltd.); and Nocrack CD (manufactured by Ouchi Shinko Chemical Industry Co., Ltd.) can also be used. Other antioxidants such as SONGNOX4120, Nowguard445, and OKABEST CLX050 can also be used. Specific examples of antioxidants are described in Japanese Patent Publication No. 4-283259 and Japanese Patent Publication No. 9-194731. The amount of antioxidant used is preferably 0.1 to 10 parts by weight, and more preferably 0.2 to 5 parts by weight, per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

[0133] (Light stabilizer) The curable composition may contain a light stabilizer. Using a light stabilizer can prevent photo-oxidative degradation of the cured product. Examples of light stabilizers include benzotriazole compounds, hindered amine compounds, and benzoate compounds. The amount of light stabilizer used is preferably 0.1 to 10 parts by weight, and more preferably 0.2 to 5 parts by weight, per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B). Specific examples of light stabilizers are described, for example, in Japanese Patent Publication No. 9-194731.

[0134] (UV absorber) The curable composition may contain an ultraviolet absorber. Using an ultraviolet absorber can improve the surface weather resistance of the cured product. Examples of ultraviolet absorbers include benzophenone compounds, benzotriazole compounds, salicylate compounds, triazine compounds, substituted tolyl compounds, and metal chelate compounds. Among these, benzotriazole compounds are particularly preferred. Specific examples of benzotriazole compounds include tinubine 234, tinubine 326, tinubine 327, tinubine 328, tinubine 329, tinubine 350, tinubine 571, tinubine 900, tinubine 928, tinubine 1130, tinubine 1600 (all manufactured by BASF); and SONGSORB 3290 (manufactured by SONGWON). Specific examples of triazine compounds include Tinuvin 400, Tinuvin 405, Tinuvin 477, and Tinuvin 1577ED (all manufactured by BASF); and SONGSORB CS400 and SONGSORB 1577 (manufactured by SONGWON). Specific examples of benzophenone compounds include SONGSORB 8100 (manufactured by SONGWON). The amount of UV absorber used is preferably 0.1 to 10 parts by weight, and more preferably 0.2 to 5 parts by weight, per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B). It is preferable to use a combination of a phenolic antioxidant or a hindered phenolic antioxidant, a hindered amine light stabilizer, and a benzotriazole UV absorber. AddworksIBC760 (manufactured by Clariant) can be used as a product containing antioxidants, light stabilizers, and UV absorbers.

[0135] (Property modifier) The curable composition may optionally contain a property modifier to adjust the tensile properties of the cured product. The property modifier is not particularly limited. Examples of property modifiers include alkylalkoxysilanes such as methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, and n-propyltrimethoxysilane; alkylisopropenoxysilanes such as dimethyldiisopropenoxysilane, methyltriisopropenoxysilane, and 3-glycidoxypropylmethyldiisopropenoxysilane; alkoxysilanes having functional groups such as 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyldimethylmethoxysilane, 3-aminopropyltrimethoxysilane, N-2-aminoethyl-3-aminopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-mercaptopropylmethyldimethoxysilane; silicone varnishes; and polysiloxanes. By using property modifiers, it is possible to increase the hardness of the cured material or, conversely, decrease its hardness and increase its elongation at break. These property modifiers may be used alone or in combination of two or more types.

[0136] In particular, compounds that produce a compound having a monovalent silanol group in the molecule upon hydrolysis have the effect of lowering the modulus of the cured product without worsening the stickiness of the surface of the cured product. Among the compounds that produce a compound having a monovalent silanol group in the molecule upon hydrolysis, compounds that produce trimethylsilanol are particularly preferred. Examples of compounds that produce a compound having a monovalent silanol group in the molecule upon hydrolysis include the compounds described in Japanese Patent Publication No. 5-117521. In addition, examples of compounds that produce trialkylsilanols such as trimethylsilanol upon hydrolysis include derivatives of alkyl alcohols such as hexanol, octanol, and decanol, and derivatives of polyhydric alcohols having 3 or more hydroxyl groups such as trimethylolpropane, glycerin, pentaerythritol, or sorbitol, which produce trialkylsilanols such as trimethylsilanol upon hydrolysis, as described in Japanese Patent Publication No. 11-241029. Examples include derivatives of oxyalkylene polymers that produce silicon compounds that generate trialkylsilanols such as trimethylsilanol upon hydrolysis, as described in Japanese Patent Publication No. 7-258534. Furthermore, polymers having a crosslinkable hydrolyzable silicon-containing group and a silicon-containing group that can become a monosilanol-containing compound upon hydrolysis, as described in Japanese Patent Publication No. 6-279693, can also be used. The property modifier is used in an amount of 0.1 to 20 parts by weight, preferably 0.5 to 10 parts by weight, per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

[0137] (Adhesive-forming resin) The curable composition may contain a tackifying resin for purposes such as improving the adhesion and bonding of the cured product to the substrate. There are no particular restrictions on the tackifying resin, and any tackifying resin commonly used in various curable compositions can be used. Specific examples of tackifying resins include terpene resins, aromatically modified terpene resins, hydrogenated terpene resins, terpene-phenol resins, phenol resins, modified phenol resins, xylene-phenol resins, cyclopentadiene-phenol resins, coumarone-indene resins, rosin resins, rosin ester resins, hydrogenated rosin ester resins, xylene resins, low molecular weight polystyrene resins, styrene copolymer resins, styrene block copolymers, hydrogenated styrene block copolymers, petroleum resins, hydrogenated petroleum resins, and DCPD resins. Examples of petroleum resins include C5 hydrocarbon resins, C9 hydrocarbon resins, and C5C9 hydrocarbon copolymer resins. These may be used individually or in combination of two or more types. The amount of tackifying resin used is preferably 2 to 100 parts by weight, more preferably 5 to 50 parts by weight, and even more preferably 5 to 30 parts by weight, per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B). Using an amount of tackifying resin within this range allows for the formation of a cured product with good adhesion and bonding to the substrate. The curable composition has an appropriate viscosity and is easy to handle.

[0138] (Compounds containing epoxy groups) The curable composition may contain compounds containing epoxy groups. Using compounds with epoxy groups can improve the resilience of the cured product. Examples of compounds with epoxy groups include epoxidized unsaturated oils and fats, epoxidized unsaturated fatty acid esters, alicyclic epoxy compounds, epichlorohydrin derivatives, and mixtures thereof. Specific examples of compounds with epoxy groups include epoxidized soybean oil, epoxidized linseed oil, bis(2-ethylhexyl)-4,5-epoxycyclohexane-1,2-dicarbonoxylate (E-PS), epoxyoctyl stearate, and epoxybutyl stearate. The amount of epoxy group-containing compound used is preferably 0.5 to 50 parts by weight per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

[0139] (Epoxy resin) The curable composition may contain an epoxy resin. Curable compositions containing an epoxy resin are preferred as adhesives, particularly as adhesives for exterior wall tiles. Examples of epoxy resins include bisphenol A type epoxy resins and novolac type epoxy resins. The ratio of the total weight of polyoxyalkylene polymer (A) and (meth)acrylic polymer (B) to the weight of epoxy resin is preferably in the range of 100 / 1 to 100 / 100, expressed as (weight of polymer (A) and polymer (B)) / (weight of epoxy resin). When polymer (A) and polymer (B) and epoxy resin are used in the above ratio, it is easy to form a high-strength cured product with excellent impact strength and toughness. When using epoxy resin, the curing composition may contain a curing agent along with the epoxy resin. The type of curing agent is not particularly limited, and commonly used curing agents can be used. The amount of hardener used is preferably 0.1 to 300 parts by weight per 100 parts by weight of epoxy resin.

[0140] (light curing substance) The curable composition may contain a photocurable substance. Using a photocurable substance forms a film of the photocurable substance on the surface of the cured product, improving the stickiness and weather resistance of the cured product. Various compounds such as organic monomers, oligomers, and resins are known as photocurable substances. Numerous compositions containing photocurable substances are also known. Representative photocurable substances include unsaturated acrylic compounds, polyvinyl polycinnamates, and azidized resins. Examples of unsaturated acrylic compounds include monomers, oligomers, or mixtures thereof having one or more acrylic or methacrylic unsaturated groups. The amount of photocurable material used is preferably 0.1 to 20 parts by weight, and more preferably 0.5 to 10 parts by weight, per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B). When an amount of photocurable material within this range is used, it is easy to form a flexible cured product with excellent weather resistance and suppressed cracking.

[0141] (oxygen curing substance) The curable composition may contain an oxygen-curable substance. Examples of oxygen-curable substances include unsaturated compounds that can react with oxygen in the air. When the curable composition contains an oxygen-curable substance, the oxygen-curable substance reacts with oxygen in the air to form a cured film near the surface of the cured product. The formation of a cured film on the surface of the cured product prevents stickiness and the adhesion of dirt and dust to the surface of the cured product. Specific examples of oxygen-curable substances include drying oils such as tung oil and linseed oil; various alkyd resins obtained by modifying drying oils; acrylic polymers, epoxy resins, and silicone resins modified with drying oils; and liquid polymers such as 1,2-polybutadiene, 1,4-polybutadiene, or polymers of C5-C8 dienes obtained by polymerizing or copolymerizing diene compounds such as butadiene, chloroprene, isoprene, or 1,3-pentadiene. These may be used individually or in combination of two or more. The amount of oxygen-curable substance used is preferably 0.1 to 20 parts by weight, and more preferably 0.5 to 10 parts by weight, per 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B). Using an amount of oxygen-curable substance within this range makes it easier to form a cured product that is less susceptible to contamination by dirt and dust on the surface and has excellent mechanical properties such as tensile strength. As described in Japanese Patent Publication No. 3-160053, the oxygen-curable substance is preferably used in combination with a photocurable substance.

[0142] Preparation of curable compositions The curable composition can be prepared as a one-component type, where all components are pre-mixed and sealed for storage, and then cured by moisture in the air after application. Alternatively, a curing agent containing a curing catalyst (D), filler, plasticizer, water, etc., can be prepared separately, and this mixture can be mixed with a polymer composition containing a polyoxyalkylene polymer (A) and a (meth)acrylic polymer before use to create a two-component type. From the viewpoint of workability, a one-component type is preferred.

[0143] When the curable composition is a one-component type, all components are mixed in advance. Therefore, it is preferable that components containing water be dehydrated and dried before use, or that they be dehydrated during mixing by reduced pressure or the like. In addition to the dehydration drying method, the storage stability of the curable composition is further improved by adding alkoxysilane compounds such as methyltrimethoxysilane, phenyltrimethoxysilane, n-propyltrimethoxysilane, vinyltrimethoxysilane, vinylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, and γ-glycidoxypropyltrimethoxysilane to the curable composition.

[0144] Uses of curable compositions Curable compositions can be used as building sealants, industrial adhesives, waterproof coating formation compositions, and adhesive raw materials. They can also be used as sealants for buildings, ships, automobiles, and roads. Furthermore, curable compositions can adhere to a wide range of substrates, including glass, porcelain, wood, metal, and resin molded products, either alone or with the help of a primer. Therefore, curable compositions can be used as various types of sealing and adhesive compositions. In addition to being ordinary adhesives, curable compositions can also be used as contact adhesives. Moreover, curable compositions are useful as food packaging materials, casting rubber materials, molding materials, and paints. The cured products of the above curable compositions exhibit low water absorption. Therefore, the above curable compositions and their cured products are particularly suitable for use as waterproofing materials such as sealants, waterproofing adhesives, and waterproof coatings. [Examples]

[0145] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples.

[0146] The number-average molecular weight in the examples is the GPC molecular weight measured under the following conditions. Liquid delivery system: Tosoh HLC-8220GPC Column: Tosoh TSKgel SuperH series Solvent: THF Molecular weight: Polystyrene equivalent Measurement temperature: 40℃

[0147] (Synthesis Example 1-1) Production of polymer (F-1) Using polyoxypropylene diol with a number average molecular weight of approximately 4,500 as an initiator, polymerization of propylene oxide was carried out in the presence of a zinc hexacyanocobaltate grime complex catalyst to obtain a hydroxyl-terminated polyoxypropylene polymer (F-1) with a number average molecular weight of approximately 28,000 and a linear structure.

[0148] (Synthesis Example 2-1) Production of polymer (A-1) After adding 1.2 equivalents of a methanol solution of sodium methoxide to the hydroxyl groups of polymer (F-1), the methanol was removed by distillation at 140°C. Then, 1.6 equivalents of 3-chloro-2-methyl-1-propene were added to the hydroxyl groups of polymer (F-1) to convert the terminal hydroxyl groups to methallyl groups. Next, 100 parts by weight of the resulting methallyl-terminated polyoxypropylene polymer were mixed with 100 ppm of a platinum divinyldisiloxane complex solution (isopropyl alcohol solution at a concentration of 3% by mass in terms of platinum), 100 ppm of a sulfur solution (hexane solution at a concentration of 0.25% by weight), and 2.3 parts by weight of (methoxymethyl)dimethoxysilane. The reaction was continued at 100°C until the remaining amount of methallyl groups was less than 1% of the amount before the reaction started. By removing excess (methoxymethyl)dimethoxysilane and other components through vacuum defloration, a linear polyoxypropylene (A-1) having (methoxymethyl)dimethoxysilyl groups at the terminals was obtained, with a silyl group / terminal group ratio of 0.7 and a number-average molecular weight of 28,500.

[0149] (Synthesis Example 3-1) Production of (meth)acrylic polymers 76.4 parts by weight of butyl acetate was added to a four-necked flask equipped with a stirrer. After creating a nitrogen atmosphere in the flask, the butyl acetate was heated to 110°C. Then, a mixed solution of 11.5 parts by weight of methyl methacrylate, 68.2 parts by weight of butyl acrylate, 14.9 parts by weight of stearyl methacrylate, 2.4 parts by weight of (3-methacryloylpropyl)methyldimethoxysilane, 3.0 parts by weight of glycidyl methacrylate, and 1.1 parts by weight of 2,2'-azobis(2-methylbutyronitrile) dissolved in 39.6 parts by weight of butyl acetate was added dropwise to the flask over 5 hours. Furthermore, 10.3 parts by weight of a 3.9 wt% butyl acetate solution of 2,2'-azobis(2-methylbutyronitrile) was added dropwise to a flask at 110°C for 1 hour, followed by polymerization for 2 hours to obtain a butyl acetate solution (solid content concentration 45 wt%) of a (meth)acrylic acid ester polymer (B-1) with a number average molecular weight of 10,428 and a weight average molecular weight of 31,173.

[0150] (Synthesis Example 4-1) 70 parts by weight of polymer (A-1) obtained in Synthesis Example 2-1 and a butyl acetate solution of polymer (B-1) obtained in Synthesis Example 3-1 were mixed so that the mass ratio of polymer (A-1) to polymer (B-1) was 70 / 30 (polymer (A-1) / polymer (B-1)). Then, using a rotary evaporator, butyl acetate was removed from the resulting mixture under reduced pressure at 110°C to obtain polymer mixture (M-1) with a solid content of 99% or more and a mass ratio of polymer (A-1) / polymer (B-1) of 70 / 30. The viscosity of polymer mixture (M-1) at 23°C was 48 Pa·s.

[0151] (Synthesis Example 4-2) (Meth)acrylic polymer (B-2) was obtained in the same manner as in Synthesis Example 3-1, except for changing the monomer composition as shown in Table 1. The polymer (A-1) obtained in Synthesis Example 2-1 and a butyl acetate solution of polymer (B-2) were mixed in the same manner as in Synthesis Example 4-1, and the butyl acetate was removed by vacuum distillation to obtain polymer mixture (M-2) with a solid content of 99% or more and a mass ratio of polymer (A-1) / polymer (B-2) of 70 / 30. The viscosity of polymer mixture (M-2) at 23°C was 47 Pa·s.

[0152] (Comparative Synthesis Example 4-1) (Meth)acrylic polymer (B-3) was obtained in the same manner as in Synthesis Example 3-1, except for changing the monomer composition as shown in Table 1. The polymer (A-1) obtained in Synthesis Example 2-1 and a butyl acetate solution of polymer (B-3) were mixed in the same manner as in Synthesis Example 4-1, and the butyl acetate was removed by vacuum distillation to obtain polymer mixture (M-3) with a solid content of 99% or more and a mass ratio of polymer (A-1) / polymer (B-3) of 70 / 30. The viscosity of polymer mixture (M-3) at 23°C was 47 Pa·s.

[0153] (Comparative Synthesis Example 4-2) 67.0 parts by weight of isobutyl alcohol were added to a four-necked flask equipped with a stirrer. After creating a nitrogen atmosphere in the flask, the isobutyl alcohol was heated to 105°C. Then, a mixed solution of 14.5 parts by weight of methyl methacrylate, 68.2 parts by weight of butyl acrylate, 14.9 parts by weight of stearyl methacrylate, 2.4 parts by weight of (3-methacryloylpropyl)methyldimethoxysilane, and 0.47 parts by weight of 2,2'-azobis(2-methylbutyronitrile) dissolved in 16.3 parts by weight of isobutyl alcohol was added dropwise to the flask over 3.5 hours. Furthermore, 3 parts by weight of a 3% by weight solution of 2,2'-azobis(2-methylbutyronitrile) in isobutyl alcohol was added dropwise to a flask at 105°C for 2 hours to carry out polymerization, yielding an isobutyl alcohol solution (solid content concentration 60% by weight) of a (meth)acrylic acid ester polymer (B-4) with a number average molecular weight of 20,600 and a weight average molecular weight of 39,100.

[0154] The polymer (A-1) obtained in Synthesis Example 2-1 and the isobutyl alcohol solution of the polymer (B-4) obtained in Comparative Synthesis Example 4-2 were mixed in the same manner as in Synthesis Example 4-1, and the isobutyl alcohol was removed by vacuum distillation to obtain a polymer mixture (M-4) with a solid content of 99% or more and a mass ratio of polymer (A-1) / polymer (B-4) of 70 / 30. The viscosity of this polymer mixture (M-4) at 23°C was 55 Pa·s.

[0155] [Table 1]

[0156] [Examples 1-5 and Comparative Examples 1-4] In the examples and comparative examples, the polymer mixtures (M-1) to (M-4) obtained in the above synthesis example were used as the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

[0157] Furthermore, in the examples and comparative examples, the following materials were used as components other than polymers. (Polyfunctional thiol (C)) Pentaerythritol tetra (3-mercaptobutyrate) (Karenz MT® PE1, manufactured by Resonac Co., Ltd.) Trimethylolpropanetri(3-mercaptobutyrate) (Kalenz MT® TPMB, manufactured by Resonac Co., Ltd.) 1,4-Butanediol di(3-mercaptobutyrate) (Kalenz MT® BD1, manufactured by Resonac Co., Ltd.) (Curing catalyst (D)) Dibutyltin bis(acetylacetonate) (Neostan U-220H, manufactured by Nitto Kasei Co., Ltd.) (Tertiary amine (E)) 2,4,6-tri(dimethylaminomethyl)phenol (manufactured by Tokyo Chemical Industry Co., Ltd.) Polyethyleneimine (number average molecular weight (Mn): 600) (manufactured by Tokyo Chemical Industry Co., Ltd.) (Dehydrating agent) Vinyltrimethoxysilane (Silquest A171, manufactured by Momentive Co., Ltd.) (Adhesion-enhancing agent) N-2-(aminoethyl)-3-aminopropyltrimethoxysilane (KBM-603, manufactured by Shin-Etsu Chemical Co., Ltd.) γ-Glycidoxypropyltrimethoxysilane (Silquest A187, manufactured by Momentive Co., Ltd.)

[0158] According to the compositions shown in Table 2, each component listed in Table 2 was mixed to obtain a mixture. The obtained mixture was uniformly kneaded and degassed using a rotary-orbit mixer to obtain the curable compositions of Examples 1-5 and Comparative Examples 1-4. The initial viscosity and the viscosity increase rate when stored at 50°C were measured for the obtained curable compositions according to the following method. The cured products obtained by curing the obtained curable compositions under a constant temperature and humidity atmosphere of 23°C and 50% relative humidity were evaluated as follows.

[0159] (viscosity) Initial viscosity V is the viscosity of the curable composition immediately after preparation. I The viscosity was measured at 23°C using a viscometer (manufactured by Toki Sangyo Co., Ltd., model number: TV-25). Furthermore, the viscosity V of the curable composition when the curable composition is held at 50°C for two weeks. 2W The viscosity V of the curable composition when the curable composition is held at 50°C for 4 weeks. 4W The viscosity was measured using the same method as for measuring the initial viscosity. Furthermore, the ratio of the viscosity after storage to the initial viscosity of the curable composition was determined. Specifically, the viscosity increase ratio when the curable composition was held at 50°C for 2 weeks and the viscosity increase ratio when the curable composition was held at 50°C for 4 weeks were calculated according to the following formula. Thickening ratio (50°C, 2 weeks) = V 2W / V I Thickening ratio (50°C, 4 weeks) = V 4W / V I

[0160] (mechanical properties) The curable composition was filled into a 2 mm thick sheet-like mold at 23°C and 50% relative humidity. The sheet was cured for 7 days at 23°C and 50% relative humidity to obtain a sheet-like cured material. The obtained cured material was punched out into a No. 3 dumbbell shape to obtain test specimens according to JIS K 6251. Using the obtained test specimens, a tensile test (tensile speed 200 mm / min) was performed using an autograph at 23°C and 50% relative humidity, and the stress at 100% elongation (M100), stress at fracture (tensile strength) (Tb), and elongation at fracture (Eb) were measured. In the case of Comparative Example 3, since it gelled when stored at high temperatures, the mechanical properties were not evaluated.

[0161] [Table 2]

[0162] According to Table 2, the curable composition of the example, comprising a polyoxyalkylene polymer (A) having a reactive silicon group, a (meth)acrylic polymer (B) having a reactive silicon group, a polyfunctional thiol (C), and a curing catalyst (D), wherein the ratio of the weight of constituent units derived from epoxy group-containing (meth)acrylic acid ester to the weight of polymer (B) is in the range of 0.1 to 5% by weight, yields a cured product that is less likely to gel even when stored at high temperatures for a long period of time, exhibits a moderately low viscosity of about 22.6 to 29.5 Pa·s, and has high tensile strength (Tb). On the other hand, comparative curable compositions in which the ratio of the weight of constituent units derived from epoxy-grouped (meth)acrylic acid ester to the weight of polymer (B) was outside the range of 0.1 to 5% by weight, or polymer (B) did not contain constituent units derived from epoxy-grouped (meth)acrylic acid ester, or did not contain polyfunctional thiol (C), resulted in cured products that gelled upon long-term storage at high temperatures, exhibited excessively low viscosity, or had poor tensile strength (Tb).

Claims

1. The material comprises a polyoxyalkylene polymer having a reactive silicon group (A), a (meth)acrylic polymer having a reactive silicon group (B), a polyfunctional thiol (C), and a curing catalyst (D). The molecular chain of the (meth)acrylic polymer (B) contains a structural unit derived from a (meth)acrylic acid ester, and also contains a structural unit derived from a (meth)acrylic acid ester having an epoxy group. The ratio of the weight of the constituent units derived from the epoxy group-containing (meth)acrylic acid ester to the weight of the (meth)acrylic polymer (B) is 0.1 to 5% by weight. The reactive silicon group is represented by the following formula (1): -SiR １ ａ X ３－ａ (1) (In formula (1), R １ is a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms, or R ０ ３ It is a triorganosiloxy group represented by SiO-, and R ０ (where is a hydrocarbon group having 1 to 20 carbon atoms, X is a hydroxyl group or a hydrolyzable group, and a is 0, 1, or 2.) A curable composition whose group is represented by [this symbol].

2. The curable composition according to claim 1, comprising a tertiary amine (E).

3. The number-average molecular weight of the polyoxyalkylene polymer (A) is 5,000 to 30,000. The curable composition according to claim 1, wherein the weight-average molecular weight of the polyoxyalkylene polymer (A) is 20,000 to 36,000.

4. The number average molecular weight of the (meth)acrylic polymer (B) is 3,000 to 60,000. The curable composition according to claim 1, wherein the weight-average molecular weight of the (meth)acrylic polymer (B) is 6,000 to 180,000.

5. The weight W of the polyoxyalkylene polymer (A) Ａ and the weight W of the (meth)acrylic polymer (B) Ｂ The ratio W Ａ / W Ｂ is 95 / 5 to 5 / 95, and the curable composition according to claim 1.

6. The curable composition according to claim 1, wherein the polyfunctional thiol (C) is a compound having a secondary thiol group.

7. The curable composition according to claim 1, wherein the amount of the polyfunctional thiol (C) is 0.01 to 20 parts by weight with respect to 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

8. The curable composition according to claim 2, wherein the amount of the tertiary amine (E) is 0.01 to 10 parts by weight with respect to 100 parts by weight of the total weight of the polyoxyalkylene polymer (A) and the (meth)acrylic polymer (B).

9. A cured product of a curable composition according to any one of claims 1 to 8.

Images