Method for prducing curable composition

Abstract

The present invention involves: a dehydration step for adding (B) an amidine structure-containing compound and (C) an alkoxysilane-containing dehydration agent to a system including (A) an organic polymer that has a reactive silicon group represented by -SiX3 (X represents a hydroxy group or a hydrolyzable group), and stirring same at 10°C-90°C under a pressure at which the alkoxysilane-containing dehydration agent (C) does not substantially volatilize; a devolatilization step for devolatilizing a volatile component included in the system including the organic polymer (A) after the dehydration step under reduced pressure; and a mixing step for mixing (C') an alkoxysilane-containing dehydration agent with the system including the organic polymer (A) after the devolatilization step. The amount of the alkoxysilane-containing dehydration agent (C) added in the dehydration step is set such that the total amount in moles of alkoxy groups directly bonded to silicon atoms contained in the alkoxysilane-containing dehydration agent (C) is 100%-300% by mol with respect to 100% by mol of the moisture content of the system including the organic polymer (A) before the dehydration step.

Description

Method for producing a curable composition

[0001] The present invention relates to a method for producing a curable composition containing an organic polymer having a silicon group bonded to a silicon atom and having a hydroxyl group or a hydrolyzable group (hereinafter also referred to as a "reactive silicon group").

[0002] It is known that an organic polymer having a reactive silicon group has a property that, even at room temperature, it crosslinks by forming a siloxane bond accompanied by a hydrolysis reaction of a silyl group due to moisture or the like, and a rubber-like cured product is obtained. Such an organic polymer having a reactive silicon group has already been industrially produced and is widely used in applications such as sealing materials, adhesives, paints, and waterproof materials.

[0003] In order to promote the curing reaction in a short time, a curing catalyst (also referred to as a silanol condensation catalyst) is usually blended in a curable composition containing an organic polymer having a reactive silicon group. As such a curing catalyst, an organotin compound having a carbon-tin bond, typified by dibutyltin bis(acetylacetonate), is known. However, since organotin-based compounds require attention from the viewpoint of environmental safety, non-tin-based curing catalysts are being studied.

[0004] In Patent Document 1, it is disclosed that an amidine structure-containing compound such as DBU (1,8-diazabicyclo[5.4.0]-7-undecene) is used as a non-tin-based curing catalyst.

[0005] On the other hand, when producing a curable composition containing an organic polymer having a reactive silicon group, in order to ensure the storage stability of the curable composition, first, the organic polymer having a reactive silicon group is mixed with additives such as a filler and a plasticizer, and then, after removing moisture under reduced pressure under heating at 100°C or higher, a curing catalyst and an adhesion-imparting agent are added (see, for example, paragraphs

[0179] -

[0180] of Patent Document 1).

[0006] It is also known to blend an alkoxysilane-containing dehydrating agent such as vinyltrimethoxysilane as a dehydrating agent (see, for example, paragraph

[0171] of Patent Document 1).

[0007] International Publication No. 2007-037483

[0008] Amidine-containing compounds such as DBU (1,8-diazabicyclo[5.4.0]-7-undecene) are promising as non-tin curing catalysts, but they tend to take a long time to cure, and there is room to improve their curability.

[0009] In view of the above situation, the present invention aims to provide a method for producing a curable composition comprising a reactive silicon group-containing organic polymer and an amidine structure-containing compound, wherein the curability is improved.

[0010] As a result of diligent research to solve the above-mentioned problems, the inventors of the present invention have found that when preparing a curable composition containing a reactive silicon group-containing organic polymer and an amidine structure-containing compound, the curability can be improved by adding the amidine structure-containing compound together with an alkoxysilane-containing dehydrating agent to a system containing the reactive silicon group-containing organic polymer, performing dehydration by stirring, then performing defloration under reduced pressure, and finally adding the alkoxysilane-containing dehydrating agent again. This led to the completion of the present invention.

[0011] In other words, the present invention relates to the following general formula (1): -SiX ３ (1) A method for producing a curable composition containing an organic polymer (A) having a reactive silicon group represented by the formula (wherein X is the same or different, representing a hydroxyl group or a hydrolyzable group), comprising: a dehydration step of adding an amidine structure-containing compound (B) and an alkoxysilane-containing dehydrating agent (C) to a system containing the organic polymer (A), and stirring at 10 to 90°C and under pressure in which the alkoxysilane-containing dehydrating agent (C) does not substantially volatilize; a defloration step of deflorating the volatile components contained in the system containing the organic polymer (A) after the dehydration step under reduced pressure; and a mixing step of mixing an alkoxysilane-containing dehydrating agent (C') to the system containing the organic polymer (A) after the defloration step, The present invention relates to a method for producing a curable composition, wherein the amount of the alkoxysilane-containing dehydrating agent (C) added in the dehydration step is such that, relative to the 100 mol% water content of the system containing the organic polymer (A) before the dehydration step, the total number of moles of alkoxy groups directly attached to silicon atoms in the alkoxysilane-containing dehydrating agent (C) is 100 mol% or more and 300 mol% or less.

[0012] According to the present invention, it is possible to provide a method for producing a curable composition having improved curability, comprising a reactive silicon group-containing organic polymer and an amidine structure-containing compound.

[0013] According to a preferred embodiment of the present invention, a curable composition can be provided that has a low moisture content, good storage stability, and improved curability. Furthermore, according to a preferred embodiment of the present invention, a curable composition can be provided that exhibits good tensile properties and / or adhesive properties after curing.

[0014] Embodiments of the present invention will be described in detail below. However, the present invention is not limited to the embodiments described below, and various modifications are possible within the scope defined in the claims. Furthermore, the configurations described below can be combined in any way, and such combinations may also constitute an embodiment of the present invention.

[0015] (Reactive silicon group-containing organic polymer (A)) The curable composition according to this disclosure contains a reactive silicon group-containing organic polymer (A) as a curable resin. The reactive silicon group-containing organic polymer (A) has a polymer skeleton (also called a main chain structure) and polymer chain ends bonded to the polymer skeleton. The polymer skeleton is a structure in which multiple monomers are bonded together by polymerization, condensation, etc., to form multiple monomer units in a continuous manner. There may be one type of monomer, or multiple types may be bonded together in a mixture.

[0016] The aforementioned polymer chain ends refer to the regions located at the ends of the reactive silicon group-containing organic polymer (A). The number of polymer chain ends in the reactive silicon group-containing organic polymer (A) is 2 if the polymer skeleton is entirely linear, and 3 or more if the polymer skeleton is entirely branched. Furthermore, if the polymer skeleton is a mixture of linear and branched structures, the average number may be between 2 and 3.

[0017] The reactive silicon groups of the organic polymer (A) may be present in the polymer backbone and / or at the polymer chain ends. Furthermore, two or more reactive silicon groups may be present at a single polymer chain end. When the curable composition according to this disclosure is used as an adhesive, sealant, elastic coating agent, or adhesive, it is preferable that the reactive silicon groups are contained within the polymer chain ends of the organic polymer (A).

[0018] The organic polymer (A) has a reactive silicon group represented by the following general formula (1): -SiX ３ (1) (In the formula, X represents a hydroxyl group or a hydrolyzable group, either the same or different.)

[0019] In general formula (1), X represents a hydroxyl group or a hydrolyzable group. The hydrolyzable group is not particularly limited and may be any known hydrolyzable group, such as a hydrogen atom, a halogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, a mercapto group, or an alkenyloxy group. Among these, alkoxy groups, acyloxy groups, ketoximate groups, and alkenyloxy groups are preferred. Because they are mildly hydrolyzable and easy to handle, alkoxy groups are more preferred, methoxy groups and ethoxy groups are even more preferred, and methoxy groups are particularly preferred. Multiple Xs may be the same or different from each other.

[0020] In the reactive silicon group described above, three X atoms are bonded to one silicon atom. Such a reactive silicon group has higher reactivity and better curability compared to reactive silicon groups having two or fewer X atoms. Furthermore, although storage stability tends to be low in general, the method for producing a curable composition according to this disclosure makes it possible to obtain a curable composition with low moisture content and good storage stability.

[0021] The reactive silicon group represented by general formula (1) is not particularly limited, but examples include trimethoxysilyl group, triethoxysilyl group, tris(2-propenyloxy)silyl group, and triacetoxysilyl group. Among these, the trimethoxysilyl group is preferred because it is easy to synthesize. Furthermore, a cured product exhibiting a high recovery rate and low water absorption rate can be obtained.

[0022] (Main chain structure of reactive silicon group-containing organic polymer (A)) The main chain structure (also called the polymer backbone) of reactive silicon group-containing organic polymer (A) is not particularly limited, and various main chain structures can be used. Specifically, polyoxyalkylene polymers such as polyoxyethylene, polyoxypropylene, polyoxybutylene, polyoxytetramethylene, polyoxyethylene-polyoxypropylene copolymer, and polyoxypropylene-polyoxybutylene copolymer; hydrocarbon polymers such as ethylene-propylene copolymer, polyisobutylene, copolymers of isobutylene and isoprene, and hydrogenated polyolefin polymers obtained by hydrogenation of these polyolefin polymers; and polyolefins obtained by condensation of dibasic acids such as adipic acid with glycol, or by ring-opening polymerization of lactones. Examples include ester polymers; (meth)acrylic acid ester polymers obtained by radical polymerization of (meth)acrylic acid ester monomers such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and stearyl (meth)acrylate; vinyl copolymers obtained by radical polymerization of (meth)acrylic acid ester monomers, vinyl acetate, acrylonitrile, styrene, and other monomers; polysulfide polymers; polyamide polymers; polycarbonate polymers, diallyl phthalate polymers, etc. In the above description, (meth)acrylic refers to acrylic and / or methacrylic.

[0023] Among these, saturated hydrocarbon polymers such as polyisobutylene, hydrogenated polyisoprene, and hydrogenated polybutadiene, polyoxyalkylene polymers, and (meth)acrylate polymers are preferred because they have a relatively low glass transition temperature and the resulting cured products have excellent cold resistance. Only one of these may be used, or two or more may be used in combination.

[0024] Polyoxyalkylene polymers and (meth)acrylate polymers are particularly preferred because they have high moisture permeability, are excellent in deep part curability when made into a one-component curable composition, and are also excellent in adhesiveness. Polyoxyalkylene polymers are more preferred, and polyoxypropylene is even more preferred.

[0025] (Meth)acrylate polymers are useful because by variously combining the monomer composition constituting the polymer, effects such as improving adhesiveness, improving heat resistance and weather resistance, and lowering the water absorption of the cured product obtained by curing the curable composition can be obtained.

[0026] The polyoxyalkylene polymer preferably has a repeating unit represented by -R-O- (wherein R is a linear or branched alkylene group having 1 to 14 carbon atoms). More preferably, R is a linear or branched alkylene group having 2 to 4 carbon atoms. Specific examples of the repeating unit represented by -R-O- include -CH ２ O-, -CH ２ CH ２ O-, -CH ２ CH(CH ３ )O-, -CH ２ CH(C ２ H ５ )O-, -CH ２ C(CH ３ )(CH ３ )O-, -CH ２ CH ２ CH ２ CH ２ O-, etc. The main chain structure of the polyoxyalkylene polymer may consist of only one type of repeating unit or may consist of two or more types of repeating units.

[0027] In particular, when the curable composition according to this disclosure is used as a sealant, adhesive, etc., a polyoxypropylene polymer having oxypropylene repeating units at a concentration of 50% by weight or more, more preferably 80% by weight or more, of the polymer main chain structure is preferred because it is amorphous and has relatively low viscosity.

[0028] The main chain structure of the polyoxyalkylene polymer may be linear or branched. When branched, the number of branches is preferably 1 to 6 (i.e., 3 to 8 terminal hydroxyl groups), more preferably 1 to 4 (i.e., 3 to 6 terminal hydroxyl groups), and most preferably 1 (i.e., 3 terminal hydroxyl groups). Having branched chains improves the resilience of the cured product. It can also be expected to reduce the water absorption of the cured product. When branched chains are present and the reactive silicon group is a trimethoxysilyl group, a cured product with particularly low water absorption can be obtained.

[0029] Polyoxyalkylene polymers are preferably obtained by a ring-opening polymerization reaction of a cyclic ether compound using a polymerization catalyst in the presence of an initiator.

[0030] 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 the cyclic ether compounds, propylene oxide is particularly preferred because it yields an amorphous and relatively low-viscosity polyether polymer.

[0031] 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 hydroxyl-terminated polyoxyalkylene polymers with a number average molecular weight of 300 to 4,000, such as polyoxypropylenediol, polyoxypropylenetriol, polyoxyethylenediol, and polyoxyethylenetriol.

[0032] Examples of synthesis methods for polyoxyalkylene polymers include, but are not limited to, polymerization methods using alkaline catalysts such as KOH, polymerization methods 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 methods using complex metal cyanide complex catalysts as shown in Japanese Patent Publication Nos. 46-27250, 59-15336, U.S. Patent Nos. 3278457, 3278458, 3278459, 3427256, 3427334, and 3427335, polymerization methods using catalysts consisting of polyphosphazene salts as exemplified in Japanese Patent Publication No. 10-273512, and polymerization methods 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.

[0033] As the reactive silicon group-containing organic polymer (A), polyoxyalkylene polymers containing other bonds such as urethane bonds and urea bonds in the main chain structure may be used, as long as the effects of the invention are not significantly impaired. A specific example of such a polymer is a polyurethane prepolymer.

[0034] Polyurethane prepolymers can be obtained by known methods, for example, by reacting a polyol compound with a polyisocyanate compound.

[0035] Examples of polyol compounds include polyether polyols, polyester polyols, polycarbonate polyols, and polyether polyester polyols.

[0036] Examples of polyisocyanate compounds include diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, methylene-bis(cyclohexyl isocyanate), isophorone diisocyanate, and hexamethylene diisocyanate. The polyurethane prepolymer may have either hydroxyl or isocyanate groups at its ends.

[0037] In terms of obtaining a curable composition with excellent storage stability and workability, it is particularly preferable that the reactive silicon group-containing organic polymer (A) is a polyoxyalkylene polymer that does not contain urethane bonds, urea bonds, ester bonds, or amide bonds in its main chain structure.

[0038] The reactive silicon group-containing organic polymer (A) is preferably obtained by introducing reactive silicon groups into the polymer by any of the following methods (a) to (d): (a) Converting the terminal hydroxyl groups of a hydroxyl-terminated organic polymer to carbon-carbon unsaturated groups, then HSiX ３ A method for reacting (wherein X is the same as that shown for general formula (1)).

[0039] (b) OCN-W-SiX at the terminal hydroxyl group of the hydroxyl-terminated organic polymer. ３ A method for reacting an isocyanate group-containing silane compound represented by the formula (wherein W is a divalent organic group, and X is the same as shown for general formula (1)).

[0040] (c) After converting the terminal hydroxyl groups of the hydroxyl-terminated organic polymer to carbon-carbon unsaturated groups, HS-W-SiX ３ A method for reacting a mercapto group-containing silane compound represented by the formula (wherein W is a divalent organic group, and X is the same as shown for general formula (1)).

[0041] (d) After synthesizing an NCO group-terminated organic polymer by reacting a hydroxyl group-terminated organic polymer with a polyisocyanate compound, HNR-W-SiX ３ (wherein W is a divalent organic group, R is hydrogen or an alkyl group, and X is the same as shown for general formula (1)) or HS-W-SiX ３ A method for reacting a silane compound represented by the formula (wherein W is a divalent organic group and X is the same as shown for general formula (1)).

[0042] 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.

[0043] In each of the above methods, the reactive silicon group-containing organic polymer (A) obtained using a silane compound in which W is represented by a methylene group is preferred in that it exhibits very high curability.

[0044] Method (a) is preferred because it tends to yield a reactive silicon group-containing organic polymer (A) with good storage stability. Methods (b), (c), and (d) are preferred because they yield a high conversion rate with a relatively short reaction time.

[0045] The introduction of reactive silicon groups by method (a) has been proposed in various publications, including 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 those described in Japanese Patent Publication Nos. 61-197631, 61-215622, 61-215623, and 61-218632, which introduce reactive silicon groups to polyoxypropylene polymers with a high molecular weight and narrow molecular weight distribution, having a number average molecular weight of 6,000 or more and an Mw / Mn ratio of 1.6 or less, by hydrosilylation, etc., and those proposed in Japanese Patent Publication No. 3-72527.

[0046] The molecular weight distribution (Mw / Mn) of the reactive silicon group-containing organic polymer (A) is not particularly limited, but is preferably 1.6 or less, more preferably 1.5 or less, and particularly preferably 1.4 or less. Furthermore, from the viewpoint of improving various mechanical properties such as the durability and elongation of the cured product, it is preferably 1.2 or less.

[0047] The number-average molecular weight of the reactive silicon group-containing organic polymer (A) is preferably 3,000 to 100,000, more preferably 5,000 to 50,000, and particularly preferably 8,000 to 35,000, as polystyrene-equivalent molecular weight in GPC. When the number-average molecular weight is within these ranges, the cured product has excellent mechanical properties, and the amount of reactive silicon groups introduced is appropriate, allowing for the production of an organic polymer (A) that exhibits good curability, has an easy-to-handle viscosity, and has excellent workability while keeping manufacturing costs within a reasonable range.

[0048] The molecular weight of reactive silicon-containing organic polymer (A) can also be expressed as the molecular weight of the end groups, determined by directly measuring the end group concentration by 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 organic polymer (degree of branching determined by the polymerization initiator used). The molecular weight of the end groups of organic polymer (A) can also 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 molecular weight of the end groups, and then converting the number average molecular weight obtained by GPC of organic polymer (A) to the molecular weight of the end groups.

[0049] To obtain a good rubber-like cured product, it is preferable that the reactive silicon groups of the organic polymer (A) are located at the ends of the polymer chains. Since this exhibits good curability and readily shows rubber elastic behavior, the number of reactive silicon groups is preferably 0.5 or more on average per polymer chain end of the organic polymer (A), more preferably 0.6 or more, even more preferably 0.7 or more, and particularly preferably 0.8 or more.

[0050] The number of polymer chain ends per molecule of organic polymer (A) is preferably 2 to 8, more preferably 2 to 4, and particularly preferably 2 or 3. The number of reactive silicon groups in one molecule of organic polymer (A) is preferably 1 to 7 on average, more preferably 1 to 3.4, and particularly preferably 1 to 2.6.

[0051] When the reactive silicon group-containing organic polymer (A) is branched, the reactive silicon group may be located at the end of the main chain, at the end of a side chain (branched chain), or both. In particular, when the reactive silicon group is at the end of the main chain, it is preferable because the molecular weight between crosslinking points becomes longer, making it easier to obtain a rubbery cured product with high strength, high elongation, and low modulus of elasticity.

[0052] As described in International Publication No. 2013 / 180203, using an organic polymer having two or more carbon-carbon unsaturated bonds at the end of one polymer chain, the organic polymer (A) obtained by the above methods (a) and (c) has two or more reactive silicon groups at the end of one polymer chain. Such organic polymer (A) exhibits high curability, and the resulting cured product can be expected to have high strength and high resilience.

[0053] Specific product examples of reactive silicon group-containing organic polymers (A) include various reactive silicon group-containing polyoxypropylene products from Kaneka Corporation under the trademark names Kaneka MS Polymer or Kaneka Cyril, reactive silicon group-containing poly(meth)acrylic acid esters such as Kaneka TA Polymer or Kaneka XMAP, and reactive silicon group-containing polyisobutylene such as Kaneka EPION.

[0054] (Amidine structure-containing compound (B)) In the method for producing the curable composition according to this disclosure, an amidine structure-containing compound (B) is used. The amidine structure-containing compound is not particularly limited as long as it is a compound containing an amidine structure, but it can be represented by the following general formula (2). R ２ N = CR ３ -NR ４ ２ (2) (wherein, R ２ , R ３ , and R ４These represent, either identical or different, a hydrogen atom, or a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. ４ They may be the same or they may be different. ２ , R ３ , and two R ４ Any two or more of these may be joined together to form a ring structure.

[0055] R ２ Since this enhances the curability of the curable composition, it is preferably a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and more preferably a hydrocarbon group in which the carbon atom adjacent to the nitrogen atom (the carbon atom at the α-position) does not have an unsaturated bond. ２ The number of carbon atoms is preferably 1 to 10, and more preferably 1 to 6, due to their availability.

[0056] R ３ This enhances the curability of the curable composition, and therefore hydrogen atoms or -NR ６ ２ It is preferable that the organic group is represented by -NR ６ ２ It is more preferable that the organic group is represented by , provided that there are two R ６ Each of these independently represents a hydrogen atom or an organic group having 1 to 20 carbon atoms. In this case, the compound represented by general formula (2) is called a guanidine compound.

[0057] Also, R ３ Because the resulting cured product has good physical properties, -NR ７ -C (=NR ８ ) - NR ９ ２ , or -N = C(NR １０ ２ ) - NR １１ ２ It is preferable that the organic group is represented by R. ７ , R ８ and two R ９ Each of these independently represents a hydrogen atom or an organic group with 1 to 6 carbon atoms. １０ and two R １１Each of these independently represents a hydrogen atom or an organic group having 1 to 6 carbon atoms. In this case, the compound represented by general formula (2) is called a biguanide compound.

[0058] The two R's in general formula (2) ４ It is preferable that the element represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and more preferably a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, because it is readily available and enhances the curability of the curable composition.

[0059] The number of carbon atoms in the amidine structure-containing compound is preferably 2 or more, more preferably 6 or more, and particularly preferably 7 or more. There is no particular upper limit to the number of carbon atoms, but it is preferably 10,000 or less.

[0060] Furthermore, the molecular weight of the amidine structure-containing compound is preferably 60 or more, more preferably 120 or more, and particularly preferably 130 or more. There is no particular upper limit to the molecular weight, but it is preferably 100,000 or less.

[0061] The amidine structure-containing compounds are not particularly limited, but examples include pyrimidine compounds such as pyrimidine, 2-aminopyrimidine, 6-amino-2,4-dimethylpyrimidine, 2-amino-4,6-dimethylpyrimidine, 1,4,5,6-tetrahydropyrimidine, 1,2-dimethyl-1,4,5,6-tetrahydropyrimidine, 1-ethyl-2-methyl-1,4,5,6-tetrahydropyrimidine, 1,2-diethyl-1,4,5,6-tetrahydropyrimidine, 1-n-propyl-2-methyl-1,4,5,6-tetrahydropyrimidine, 2-hydroxy-4,6-dimethylpyrimidine, 1,3-diazanaphthalene, and 2-hydroxy-4-aminopyrimidine; Imidazolin compounds such as 2-imidazoline, 2-methyl-2-imidazoline, 2-ethyl-2-imidazoline, 2-propyl-2-imidazoline, 2-vinyl-2-imidazoline, 1-(2-hydroxyethyl)-2-methyl-2-imidazoline, 1,3-dimethyl-2-iminoimidazolidine, and 1-methyl-2-iminoimidazolidine-4-one; amidine compounds such as 1,8-diazabicyclo[5.4.0]undeca-7-ene (DBU), 1,5-diazabicyclo[4.3.0]nona-5-ene (DBN), 2,9-diazabicyclo[4.3.0]nona-1,3,5,7-tetraene, and 6-(dibutylamino)-1,8-diazabicyclo[5,4,0]undecene-7 (DBA-DBU);Guanidine, dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, 1,1-dimethylguanidine, 1,3-dimethylguanidine, 1,2-diphenylguanidine, 1,1,2-trimethylguanidine, 1,2,3-trimethylguanidine, 1,1,3,3-tetramethylguanidine, 1,1,2,3,3-pentamethylguanidine, 2-ethyl-1,1,3,3-tetramethylguanidine, 1,1,3,3-tetramethyl-2-n-propylguanidine, 1,1,3,3-tetramethyl-2-isopropylguanidine, 2-n-butyl-1,1,3,3-tetramethylguanidine, 2-tert-butyl-1,1,3,3-tetramethylguanidine, 1,2,3-Tricyclohexylguanidine, 1-Benzyl-2,3-dimethylguanidine, 1,5,7-Triazabicyclo[4.4.0]deca-5-ene, 7-Methyl-1,5,7-Triazabicyclo[4.4.0]deca-5-ene, 7-Ethyl-1,5,7-Triazabicyclo[4.4.0]deca-5-ene, 7-n-Propyl-1,5,7-Triazabicyclo[4.4.0] Guanidine compounds such as deca-5-ene, 7-isopropyl-1,5,7-triazabicyclo[4.4.0]deca-5-ene, 7-n-butyl-1,5,7-triazabicyclo[4.4.0]deca-5-ene, 7-cyclohexyl-1,5,7-triazabicyclo[4.4.0]deca-5-ene, and 7-n-octyl-1,5,7-triazabicyclo[4.4.0]deca-5-ene;Biguanides, 1-methyl biguanide, 1-ethyl biguanide, 1-n-butyl biguanide, 1-(2-ethylhexyl) biguanide, 1-n-octadecyl biguanide, 1,1-dimethyl biguanide, 1,1-diethyl biguanide, 1-cyclohexyl biguanide, 1-allyl biguanide, 1-phenyl biguanide, 1-(o-tolyl) biguanide, 1-morpholinobiguanide, Examples include biguanide compounds such as 1-n-butyl-N2-ethyl biguanide, 1,1'-ethylenebisbiguanide, 1,5-ethylene biguanide, 1-[3-(diethylamino)propyl]biguanide, 1-[3-(dibutylamino)propyl]biguanide, and N',N''-dihexyl-3,12-diimino-2,4,11,13-tetraazatetradecanediamidine. Only one type of amidine structure-containing compound may be used, or two or more types may be used in combination.

[0062] The amidine structure-containing compound is preferably an amidine compound or a guanidine compound, with DBU, DBA-DBU, DBN, or phenylguanidine being more preferred, DBU, DBA-DBU, or DBN being even more preferred, and DBU being particularly preferred.

[0063] (Alkoxysilane-containing dehydrating agent (C) or (C')) An alkoxysilane-containing dehydrating agent refers to an alkoxysilane compound that functions as a dehydrating agent. This alkoxysilane compound is a compound having an alkoxy group directly attached to a silicon atom, and the alkoxy group reacts with water to hydrolyze and produce an alcohol, thereby reducing the water content of the system containing the organic polymer (A). However, alkoxysilane compounds having an amino group do not qualify as alkoxysilane-containing dehydrating agents because, although they function as dehydrating agents, they have the problem of adhering to the walls of the mixer during the dehydration process and being difficult to remove.

[0064] Alkyloxysilane-containing dehydrating agents used in the dehydration process are denoted with (C), and alkoxysilane-containing dehydrating agents used in the mixing process are denoted with (C'). Components (C) and (C') may be the same alkoxysilane-containing dehydrating agent or different alkoxysilane-containing dehydrating agents.

[0065] In alkoxysilane-containing dehydrating agents, the number of carbon atoms in the alkoxy group directly bonded to the silicon atom is not particularly limited, but is usually around 1 to 3. The alkoxy group is preferably a methoxy group or an ethoxy group, with the methoxy group being more preferred.

[0066] The molecular weight of the alkoxysilane-containing dehydrating agent is not particularly limited, but is usually in the range of 100 to 1,500. The lower limit of the molecular weight may be 150 or more. The upper limit may be 1,000 or less, or 500 or less.

[0067] The alkoxysilane-containing dehydrating agent may be a compound having an alkoxy group directly attached to a silicon atom and a reactive group other than an amino group, or it may be a compound that does not have a reactive group other than an alkoxy group directly attached to a silicon atom.

[0068] Specific examples of alkoxysilane-containing dehydrating agents include epoxy-containing silanes such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltriethoxysilane; and isocyanate-containing silanes such as γ-isocyanatetopropyltrimethoxysilane, γ-isocyanatetopropyltriethoxysilane, γ-isocyanatetopropylmethyldiethoxysilane, γ-isocyanatetopropylmethyldimethoxysilane, (isocyanatemethyl)trimethoxysilane, and (isocyanatemethyl)dimethoxymethylsilane. Silanes containing mercapto groups such as γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, and mercaptomethyltriethoxysilane; carboxysilanes such as β-carboxyethyltriethoxysilane, β-carboxyethylphenylbis(2-methoxyethoxy)silane, and N-β-(carboxymethyl)aminoethyl-γ-aminopropyltrimethoxysilane; silanes containing vinyl-type unsaturated groups such as vinyltrimethoxysilane, vinylmethyldimethoxysilane, and vinyltriethoxysilane; silanes containing (meth)acrylic-type unsaturated groups such as γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-acryloxypropylmethyltriethoxysilane, and γ-acryloxypropyltrimethoxysilane; Examples include silanes without reactive groups such as methyltrimethoxysilane, dimethyldimethoxysilane, n-propyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, dimethoxydiphenylsilane, hexyltrimethoxysilane, 1,6-bis(trimethoxylyl)hexane, (methoxymethyl)trimethoxysilane, and p-styryltrimethoxysilane; halogen-containing silanes such as γ-chloropropyltrimethoxysilane; and isocyanurate silanes such as tris(trimethoxysilyl)isocyanurate.Alkoxysilane-containing dehydrating agents may be used individually or in combination of two or more. Partial hydrolysis condensates of the silane compounds listed above can also be used. Examples include Evonik's Dynasylan 6490 and Dynasylan 6498.

[0069] Because they exhibit good dehydration performance, the alkoxysilane-containing dehydrating agent is preferably vinyltrimethoxysilane, methyltrimethoxysilane, phenyltrimethoxysilane, or (methoxymethyl)trimethoxysilane, more preferably vinyltrimethoxysilane or (methoxymethyl)trimethoxysilane, and particularly preferably vinyltrimethoxysilane.

[0070] (Curing Catalyst) The curable composition according to this disclosure contains a curing catalyst to promote the hydrolysis and condensation reaction of the reactive silicon groups of the organic polymer (A). The amidine structure-containing compound (B) functions as the curing catalyst. The curable composition according to this disclosure may contain only the amidine structure-containing compound (B) as the curing catalyst, but may further contain a curing catalyst other than the amidine structure-containing compound (B). Examples of curing catalysts other than component (B) include organotin compounds, metal carboxylic acid salts, amine compounds other than the amidine structure-containing compound, carboxylic acids, metal alkoxides, and inorganic acids.

[0071] The curable composition according to this disclosure may contain a titanium compound or its condensate (D) as a curing catalyst, but it is preferable that it does not contain one. If component (D) is not included, the problem of discoloration caused by the titanium compound can be avoided.

[0072] The titanium compound is represented by the following general formula (3): Ti(OR ５ ) ｄ Y ４－ｄ (3) (wherein, R ５ (where represents a substituted or unsubstituted hydrocarbon group with 1 to 20 carbon atoms; Y represents a chelate coordination compound; and d represents 0 or an integer from 1 to 4.)

[0073] A condensate of the titanium compound represented by the general formula (3) can also be used as component (D). This condensate can be obtained by adding water to the titanium compound and reacting it. Alternatively, the titanium compound and the condensate of the titanium compound may be used in combination.

[0074] R ５ The substituted or unsubstituted hydrocarbon group indicated by is preferably a substituted or unsubstituted aliphatic or aromatic hydrocarbon group, with aliphatic hydrocarbon groups being preferred. Examples of aliphatic hydrocarbon groups include saturated or unsaturated hydrocarbon groups. Examples of saturated hydrocarbon groups include linear or branched alkyl groups. The number of carbon atoms in the hydrocarbon group is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 4.

[0075] R ５ Examples of hydrocarbon groups represented by include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, nonyl, and decyl. Examples of substituents that the hydrocarbon group may have include methoxy, ethoxy, hydroxyl, and acetoxy groups. ５ If multiple instances exist, they may be identical or different from one another.

[0076] The chelate-coordinating compound represented by Y may be any known compound that is known to coordinate to titanium. While not particularly limited, examples include 1-aryl-1,3-butanedione such as 2,4-pentanedione, 2,4-hexanedione, 2,4-pentadecanedione, 2,2,6,6-tetramethyl-3,5-heptanedione, 1-phenyl-1,3-butanedione, 1-(4-methoxyphenyl)-1,3-butanedione, 1,3-diaryl-1,3-propanedione such as 1,3-diphenyl-1,3-propanedione, 1,3-bis(2-pyridyl)-1,3-propanedione, and 3-benzyl Examples include diketones such as -2,4-pentanedione; ketoesters such as methyl acetate, ethyl acetate, butyl acetate, t-butyl acetate, and ethyl 3-oxohexanoate; ketoamides such as N,N-dimethylacetate, N,N-diethylacetate, and acetacetanilide; malonic acid esters such as dimethyl malonate, diethyl malonate, and diphenyl malonate; and malonic acid amides such as N,N,N',N'-tetramethylmalonamide and N,N,N',N'-tetraethylmalonamide. Among these, diketones and ketoesters are preferred. If there are multiple Ys, they may be the same or different from each other.

[0077] d represents 0 or an integer from 1 to 4. In order for the curable composition according to this disclosure to exhibit better curability and to exhibit greater elongation after curing, d is preferably 0 or an integer from 1 to 3, more preferably an integer from 1 to 3, and particularly preferably 2.

[0078] Specific examples of titanium compounds or condensates represented by general formula (3) include tetramethoxytitanium, trimethoxyethoxytitanium, trimethoxyisopropoxytitanium, trimethoxybutoxytitanium, dimethoxydiethoxytitanium, dimethoxydiisopropoxytitanium, dimethoxydibutoxytitanium, methoxytriethoxytitanium, methoxytriisopropoxytitanium, methoxytributoxytitanium, tetraethoxytitanium, triethoxyisopropoxytitanium, triethoxybutoxytitanium, diethoxydiisopropoxytitanium, diethoxydibutoxytitanium Examples include toxicitamin, ethoxytriisopropoxytitamin, ethoxytributoxytitamin, tetraisopropoxytitamin, triisopropoxybutoxytitamin, diisopropoxydibutoxytitamin, tetrabutoxytitamin, tetratert-butoxytitamin, diisopropoxytitamin bis(acetylacetonate), diisopropoxytitamin bis(ethylacetoacetate), diisobutoxytitamin bis(ethylacetoacetate); and condensates of titanium alkoxides such as tetrabutoxytitamin dimer and tetrabutoxytitamin tetramer. Only one type of titanium compound or its condensate may be used, or two or more types may be used in combination.

[0079] Because good curability can be obtained and large elongation can be observed after curing, the titanium compound represented by general formula (3) is preferably a compound containing a chelate coordination compound represented by Y, and specifically, diisopropoxytitanium bis(acetylacetonate), diisopropoxytitanium bis(ethylacetoacetate), and diisobutoxytitanium bis(ethylacetoacetate) are particularly preferred.

[0080] (Adhesion-imparting agent) The curable composition according to this disclosure does not need to contain an adhesion-imparting agent, but it is preferable that it contains one. By incorporating an adhesion-imparting agent, the adhesion of the cured product obtained by curing the curable composition to various substrates can be improved.

[0081] Examples of adhesion-imparting agents include silane compounds (also called aminosilanes) having a hydrolyzable silicon group and a substituted or unsubstituted amino group. The hydrolyzable silicon group refers to a silicon atom-containing group to which a hydrolyzable group is bonded, and the reactive silicon group of an organic polymer (A) can also be represented by the general formula (1) described above. However, in the case of the hydrolyzable silicon group, the number of X groups per silicon atom is not limited to 3, but may be any of 1 to 3.

[0082] The hydrolyzable groups included in the hydrolyzable silicon group are not particularly limited, and examples 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, alkoxy groups such as methoxy groups and ethoxy groups are more preferred because they are mildly hydrolyzable and easy to handle, with methoxy groups and ethoxy groups being particularly preferred.

[0083] In some cases, it is preferable to have three hydrolyzable groups bonded to silicon atoms in the silane compound, which is an adhesion promoter, in order to ensure good adhesion. In other cases, it may be preferable to have two groups to ensure the storage stability of the curable composition.

[0084] The substituents on the substituted amino group are not particularly limited and include, for example, alkyl groups, aralkyl groups, and aryl groups.

[0085] The molecular weight of the silane compound used as an adhesion promoter is not particularly limited, but is usually in the range of 100 to 1,500. The lower limit of the molecular weight may be 150 or more. The upper limit may be 1,000 or less, or 500 or less.

[0086] Specific examples of silane compounds that act as adhesion promoters include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-(2-aminoethyl)aminopropylmethyldimethoxysilane, γ-(2-aminoethyl)aminopropyltriethoxysilane, γ-(2-aminoethyl)aminopropylmethyldiethoxysilane, γ-(2-(2-aminoethyl)aminoethyl)aminopropyltrimethoxysilane, γ-(6-aminohexyl)aminopropyltrimethoxysilane, 3-(N-ethylamino)-2-methylpropyltrimethoxysilane, γ-ureidopropyltrimethoxysilane, γ-ureidopropyl Examples of amino group-containing silanes include Idopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-benzyl-γ-aminopropyltrimethoxysilane, N-vinylbenzyl-γ-aminopropyltriethoxysilane, N-cyclohexylaminomethyltriethoxysilane, N-cyclohexylaminomethyldiethoxymethylsilane, N-phenylaminomethyltrimethoxysilane, N-butylaminopropyltrimethoxysilane, (2-aminoethyl)aminomethyltrimethoxysilane, 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. In addition, partially hydrolyzed condensates of the amino group-containing silanes mentioned above, or partially hydrolyzed condensates of amino group-containing silanes with other alkoxysilanes (for example, reaction products of amino group-containing silane and epoxy group-containing silane, reaction products of amino group-containing silane and (meth)acrylic group-containing silane), etc., can also be used. Only one type of silane compound may be used, or two or more types may be used in combination.

[0087] To achieve good adhesion, the silane compound used as the adhesion imparting agent is preferably γ-aminopropyltrimethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, or γ-(2-aminoethyl)aminopropylmethyldimethoxysilane. Silane coupling agents obtained by partially condensing hydrolyzable silicon groups to form oligomers are suitable in terms of safety and stability. The silane coupling agents to be condensed may be a single type or multiple types. Examples of oligomerized silane coupling agents include Dynasylan 1146 from Evonik. To ensure the storage stability of the curable composition, γ-aminopropyltrimethoxysilane and γ-(2-aminoethyl)aminopropylmethyldimethoxysilane are preferred.

[0088] (Dehydration step) In the method for producing a curable composition according to the present disclosure, first, an organic polymer (A) is prepared, and after adding any additive such as a plasticizer or filler to the organic polymer (A), a dehydration step is performed. This makes it possible to reduce the water content of the system containing the organic polymer (A).

[0089] Conventional methods, such as those described in the examples of Patent Document 1, involved a dehydration process in which water was evaporated by heating to a high temperature of 100°C or higher and under reduced pressure. However, while curable compositions obtained by such physical dehydration had good storage stability, their curability was sometimes insufficient.

[0090] In contrast to such conventional methods, the method for producing a curable composition according to this disclosure involves chemical dehydration using an alkoxysilane-containing dehydrating agent (C). In this chemical dehydration, the alkoxy groups in the alkoxysilane-containing dehydrating agent (C) react with water and undergo hydrolysis to produce alcohol, thereby reducing the water content of the system containing the organic polymer (A). The curable composition obtained by the production method including chemical dehydration according to this disclosure can have significantly improved curability compared to a curable composition obtained by physical dehydration in the conventional method.

[0091] In the manufacturing method described herein, since chemical dehydration is performed, it is preferable not to perform a physical dehydration step that involves heating to a high temperature of 100°C or higher. This makes it possible to reduce the energy and costs required for physical dehydration.

[0092] The amount of alkoxysilane-containing dehydrating agent (C) added in the dehydration step is set so that the total number of moles of alkoxy groups directly attached to silicon atoms in the alkoxysilane-containing dehydrating agent (C) is between 100 mol% and 300 mol% relative to the 100 mol% water content of the system containing the organic polymer (A) before the dehydration step. If the total number of moles of alkoxy groups relative to 100% of the moles of water is less than 100 mol%, the amount of dehydrating agent present is insufficient, making it difficult to sufficiently reduce the water content of the system and thus preventing the achievement of good storage stability. Preferably, the total number of moles of alkoxy groups is 150 mol% or more.

[0093] Furthermore, if the total number of moles of alkoxy groups exceeds 300 mol%, the alkoxysilane-containing dehydrating agent (C) may react with the reactive silicon groups of the organic polymer (A), resulting in insufficient improvement in curability. The total number of moles of the alkoxy groups is preferably 250 mol% or less, and more preferably 200 mol% or less.

[0094] In the dehydration step, an amidine structure-containing compound (B) is added to the system containing the organic polymer (A) in addition to an alkoxysilane-containing dehydrating agent (C). The amidine structure-containing compound (B) functions as a catalyst (i.e., a dehydration catalyst) that promotes the reaction between component (C) and water, and can efficiently reduce the water content of the system. Furthermore, component (B) can also function as a curing catalyst when curing the curable composition.

[0095] Even when using only an alkoxysilane-containing dehydrating agent (C) without adding the amidine structure-containing compound (B), the water content of the system does not decrease sufficiently, and good storage stability or curability cannot be achieved. Similarly, the same result occurs when amine compounds other than component (B) are added, and good storage stability or curability cannot be achieved.

[0096] The amount of the amidine structure-containing compound (B) added in the dehydration process can be appropriately set from the viewpoint of promoting the reaction between component (C) and water and promoting the curing reaction. Specifically, from the viewpoint of improving storage stability and curability by adding component (B), it is preferable that the amount is 0.1 parts by weight or more, more preferably 0.2 parts by weight or more, even more preferably 0.3 parts by weight or more, even more preferably 0.4 parts by weight or more, and particularly preferably 0.5 parts by weight or more, per 100 parts by weight of organic polymer (A).

[0097] (B) There is no particular upper limit to the amount of component added, but since adding a large amount of component (B) can cause the problem of bleed-out to the surface after curing, it is more preferable to add 2 parts by weight or less, even more preferable to add 1.5 parts by weight or less, and particularly preferable to add 1 part by weight or less.

[0098] The amidine structure-containing compound (B) and the alkoxysilane-containing dehydrating agent (C) are added to the system containing the organic polymer (A). The "system containing the organic polymer (A)" may consist only of the organic polymer (A), but it is preferable that it is a mixture containing the organic polymer (A) and additives such as plasticizers and fillers.

[0099] As additives that can be incorporated into the above mixture, additives known to be incorporated into curable compositions containing organic polymers having reactive silicon groups can be used as appropriate. Specifically, these include, but are not limited to, plasticizers, fillers, property modifiers, anti-sagging agents (thixotropic agents), antioxidants, light stabilizers, UV absorbers, conductive fillers, flame retardants, curing modifiers, radical inhibitors, metal deactivators, ozone degradation inhibitors, phosphorus-based peroxide decomposers, lubricants, pigments, foaming agents, solvents, and antifungal agents. Any of these additives can be any component, but it is preferable to use at least one selected from the group consisting of plasticizers and fillers.

[0100] When adding the amidine structure-containing compound (B) and the alkoxysilane-containing dehydrating agent (C) to a system containing the organic polymer (A), they may be added sequentially or simultaneously. Furthermore, the order of sequential addition is not particularly limited. Alternatively, components (B) and (C) may be mixed beforehand before being added to the system containing the organic polymer (A).

[0101] After adding components (B) and (C) to a system containing organic polymer (A), the system is stirred for a predetermined time to allow the reaction between component (C) and water to proceed and reduce the water content of the system. The stirring method is not particularly limited and can be carried out using conventionally known apparatus.

[0102] During the stirring process, the temperature of the system should be within the range of 10 to 90°C. If the temperature is below 10°C, the reaction between component (C) and water may not proceed sufficiently, making it difficult to sufficiently reduce the water content of the system. Conversely, if the temperature exceeds 90°C, it may also be difficult to sufficiently reduce the water content of the system. The lower limit of the temperature is preferably 20°C or higher, more preferably 30°C or higher, even more preferably 40°C or higher, even more preferably 50°C or higher, and particularly preferably 60°C or higher. The upper limit of the temperature is preferably 80°C or lower, more preferably 70°C or lower.

[0103] The stirring is preferably carried out under pressure at which component (C) does not substantially volatilize. Stirring under pressure at which component (C) volatilizes does not sufficiently achieve the effect of reducing the water content of the system. Here, pressure at which component (C) does not substantially volatilize means pressure at which, during stirring that satisfies the above temperature conditions, the amount of reduction of component (C) due to volatilization is 10% or less (preferably 1% or less).

[0104] Examples of atmospheric pressure at which component (C) does not substantially volatilize include atmospheric pressure or above, or a reduced pressure to the extent that component (C) does not substantially volatilize. Preferably, it is atmospheric pressure or above, and more preferably atmospheric pressure.

[0105] The time for which the stirring is performed is preferably the time required for the reaction between component (C) and water to proceed and for the water content of the system to be sufficiently reduced. Typically, such dehydration takes longer than the time required for stirring aimed solely at uniformly mixing each component. The stirring time required for dehydration can be determined by measuring the water content of the system and depends on the temperature and pressure conditions, but is usually preferably 10 minutes or more, more preferably 20 minutes or more, and even more preferably 30 minutes or more. There is no particular upper limit to the stirring time, but since the progress of the reaction due to stirring will plateau, it may be, for example, 120 minutes or less, 90 minutes or less, or 60 minutes or less.

[0106] The dehydration process described above can reduce the water content of the system containing the organic polymer (A). From the viewpoint of achieving good storage stability, the water content of the system after the dehydration process is preferably 1,200 ppm or less, more preferably 1,000 ppm or less, and even more preferably 800 ppm or less.

[0107] On the other hand, the water content of the system containing the organic polymer (A) before the dehydration step is not particularly limited, but since there is great significance in reducing the water content by applying the manufacturing method according to this disclosure, it is preferably 1,500 ppm or more, and more preferably 2,000 ppm or more. The upper limit is not particularly limited, but for example, it may be 10,000 ppm or less, 5,000 ppm or less, or 3,000 ppm or less.

[0108] (Devolatilization Step) In the method for producing a curable composition according to the present disclosure, following the dehydration step described above, a defoliation step is performed to defoliate volatile components contained in the system containing the organic polymer (A) under reduced pressure. Since alcohol is generated by the reaction of component (C) with water in the dehydration step, the system after the dehydration step will contain alcohol. In the defoliation step, this alcohol is removed by volatilization. Furthermore, if the system after the dehydration step contains unreacted component (C), this component (C) can also be removed by volatilization. Moreover, by removing the alcohol product, the reaction between component (C) and water will proceed further, and it can be expected that the water content of the system will be further reduced.

[0109] If the defoliation process is not performed, the curable composition will contain volatile components such as alcohol, which raises concerns about hazards due to these volatile components. Furthermore, there is a concern that the sealed container may expand when the curable composition is stored in a sealed container, especially in high temperatures such as during the summer.

[0110] The defoliation process is carried out under reduced pressure. The degree of reduced pressure is not particularly limited; it should be sufficient to cause the alcohol produced in the dehydration process to volatilize, depending on the type of alcohol produced.

[0111] The temperature in the defoliation process is not particularly limited and can be determined according to the type of alcohol product and the degree of reduced pressure, but it may be within the range of approximately 10 to 90°C. The upper limit of the temperature may be 70°C or less, or 50°C or less. The temperature may also be room temperature (approximately 15 to 25°C).

[0112] (Mixing step) Next, a step is performed in which an alkoxysilane-containing dehydrating agent (C') is mixed with the system containing the organic polymer (A) after the defoliation step. This improves the storage stability of the curable composition containing the organic polymer (A) which has a reactive silicon group in which three X atoms are bonded to one silicon atom.

[0113] The amount of alkoxysilane-containing dehydrating agent (C') added in the mixing step can be set appropriately from the viewpoint of storage stability, but specifically, it is preferably 1 part by weight or more, more preferably 2 parts by weight or more, even more preferably 3 parts by weight or more, even more preferably 4 parts by weight or more, and particularly preferably 5 parts by weight or more, per 100 parts by weight of organic polymer (A).

[0114] There is no particular upper limit to the amount of component (C') added, but since the storage stability improvement effect achieved by adding component (C') plateaus, it is preferably 15 parts by weight or less, more preferably 10 parts by weight or less, even more preferably 8 parts by weight or less, and particularly preferably 6 parts by weight or less.

[0115] In the method for producing the curable composition according to this disclosure, it is preferable that the alkoxysilane-containing dehydrating agent is added only twice, in the dehydration step and the mixing step.

[0116] In this mixing step, a curing catalyst and / or adhesion promoter may be further mixed with the alkoxysilane-containing dehydrating agent (C'). Further mixing of an adhesion promoter is particularly preferable. The mixing of an adhesion promoter improves the adhesion of the cured product obtained by curing the curable composition to various substrates. The aminosilanes mentioned above can be used as adhesion promoters.

[0117] The amount of adhesion promoter added is not particularly limited and can be set appropriately depending on the type of adhesion promoter and the desired adhesion, but it is preferably 0 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, and even more preferably 1 to 8 parts by weight per 100 parts by weight of organic polymer (A).

[0118] The amount of curing catalyst added in the mixing step is not particularly limited and can be set according to the type of curing catalyst and the desired curability. For example, it may be 15 parts by weight or less, 10 parts by weight or less, or 5 parts by weight or less per 100 parts by weight of reactive silicon group-containing organic polymer (A). The lower limit is also not particularly limited and may be 0 parts by weight or more, 0.1 parts by weight or more, 0.5 parts by weight or more, or 1 part by weight or more. However, the addition of curing catalyst in the mixing step may be omitted.

[0119] By sealing the curable composition obtained through the processes described above into a sealable container, it is possible to prepare a one-component curable composition that hardens due to moisture in the air after application. According to the method for producing a curable composition of this disclosure, the moisture content of the system can be reduced by the dehydration process, so a one-component curable composition with good storage stability can be provided.

[0120] Furthermore, it is also possible to prepare a two-component curable composition by preparing the curable composition obtained through the processes described above as the main component, and separately preparing a curing agent containing components such as a curing catalyst and water, thereby mixing the main component and curing agent before use.

[0121] The curable composition according to this disclosure can be used as a building sealant, industrial adhesive, waterproof coating, or adhesive raw material. It can also be used as a sealant for buildings, ships, automobiles, roads, etc. Furthermore, since it can adhere to a wide range of substrates such as glass, porcelain, wood, metal, and resin molded products, either alone or with the help of a primer, it can also be used as various types of sealing and adhesive compositions. In addition to being an ordinary adhesive, it can also be used as a contact adhesive. Furthermore, it is useful as a food packaging material, casting rubber material, molding material, and paint.

[0122] The following sections list preferred embodiments of this disclosure, but the present invention is not limited to these sections. [Section 1] The following general formula (1): -SiX ３(1) A method for producing a curable composition containing an organic polymer (A) having a reactive silicon group represented by the formula (wherein X is the same or different, representing a hydroxyl group or a hydrolyzable group), comprising: a dehydration step of adding an amidine structure-containing compound (B) and an alkoxysilane-containing dehydrating agent (C) to a system containing the organic polymer (A), and stirring at 10 to 90°C and under pressure in which the alkoxysilane-containing dehydrating agent (C) does not substantially volatilize; a defloration step of deflorating the volatile components contained in the system containing the organic polymer (A) after the dehydration step under reduced pressure; and a mixing step of mixing an alkoxysilane-containing dehydrating agent (C') to the system containing the organic polymer (A) after the defloration step, A method for producing a curable composition, wherein the amount of the alkoxysilane-containing dehydrating agent (C) added in the dehydration step is such that the total number of moles of alkoxy groups directly attached to silicon atoms in the alkoxysilane-containing dehydrating agent (C) is 100 mol% or more and 300 mol% or less, relative to the 100 mol% water content of the system containing the organic polymer (A) before the dehydration step. [Item 2] The method for producing a curable composition, wherein the stirring time in the dehydration step is 20 minutes or more. [Item 3] The method for producing a curable composition, wherein the temperature in the dehydration step is 40°C or higher. [Item 4] The method for producing a curable composition, wherein the amount of the amidine structure-containing compound (B) added is 0.2 parts by weight or more per 100 parts by weight of the organic polymer (A). [Item 5] The amidine structure-containing compound (B) is the following general formula (2): R ２ N = CR ３ -NR ４ ２ (2) (wherein, R ２ , R ３ , and R ４ These represent, either identical or different, a hydrogen atom, or a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. ４ They may be the same or they may be different. ２ , R ３ , and two R ４Any two or more of these may be combined to form a cyclic structure.) A manufacturing method according to any one of items 1 to 4. [Item 6] A manufacturing method according to any one of items 1 to 5, wherein the addition of the alkoxysilane-containing dehydrating agent is performed only twice in total, in the dehydration step and the mixing step. [Item 7] A manufacturing method according to any one of items 1 to 6, wherein an adhesion promoter is further mixed in the mixing step. [Item 8] The curable composition is represented by the following general formula (3): Ti(OR ５ ) ｄ Y ４－ｄ (3) (wherein, R ５ A method for producing a titanium compound or its condensate (D) represented by (C) represents a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. Y represents a chelate coordination compound. d represents 0 or an integer from 1 to 4. [Item 9] A method for producing a titanium compound or its condensate (D) represented by (C) represents a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms Y represents a chelate coordination compound. d represents 0 or an integer from 1 to 4. [Item 10] A method for producing a titanium compound or its condensate (D) represented by (C) represents a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. [Item 11] A method for producing a titanium compound or its condensate (D) represented by (C) represents a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. [Item 9] A method for producing a titanium compound or its condensate (D) represented by (C) represents a chelate coordination compound.

[0123] The present invention will be described in more detail below with reference to specific examples, but the present invention is not limited to the following examples.

[0124] The number-average molecular weight in the examples is the GPC molecular weight measured under the following conditions: Liquid delivery system: Tosoh HLC-8420GPC Column: Tosoh TSKgel SuperH series Solvent: THF Molecular weight: Polystyrene equivalent Measurement temperature: 40°C

[0125] The average number of silyl groups per terminal or per molecule of the polymers shown in the examples was determined by 1H-NMR (using a Bruker AVANCE III HD-500) using CDClone. ３ The results were calculated by measurement (measured in a solvent).

[0126] <Synthesis of Organic Polymers> (Synthesis Example 1 (A-1)) Using polyoxypropylenediol with a molecular weight of approximately 2,000 as an initiator, propylene oxide was polymerized using a zinc hexacyanocobaltate grime complex catalyst to obtain polypropylene oxide with a number average molecular weight of 28,500 (polystyrene-equivalent molecular weight measured using a Tosoh HLC-8120GPC liquid delivery system, a Tosoh TSK-GEL H-type column, and THF solvent). Subsequently, 1.2 molar equivalents of a methanol solution of NaOMe was added to the hydroxyl groups of this hydroxyl-terminated polypropylene oxide, and the methanol was removed by distillation. Then, allyl chloride was added to convert the terminal hydroxyl groups to allyl groups. Unreacted allyl chloride was removed by defoliation under reduced pressure. To 100 parts by weight of the obtained unpurified allyl-terminated polypropylene oxide, 300 parts by weight of n-hexane and 300 parts by weight of water were mixed and stirred. The water was then removed by centrifugation, and another 300 parts by weight of water was mixed and stirred into the resulting hexane solution. The water was removed again by centrifugation, and the hexane was removed by defloration under reduced pressure. This yielded a bifunctional polypropylene oxide with a number-average molecular weight of approximately 28,500 and allyl groups at the ends. To 100 parts by weight of the obtained allyl-terminated polypropylene oxide, 0.8 molar equivalents of trimethoxysilane relative to the allyl groups of the allyl-terminated polypropylene oxide were reacted with 150 ppm of a 2-propanol solution of a platinum vinylsiloxane complex with a platinum content of 3 wt% as a catalyst at 90°C for 5 hours to obtain a trimethoxysilyl-terminated polyoxypropylene polymer (A-1). The number of trimethoxysilyl groups was approximately 0.8 per polymer chain end.

[0127] (Synthesis Example 2 (A-2)) Using a 1 / 1 (weight ratio) mixture of polyoxypropylenediol with a molecular weight of approximately 2,000 and polyoxypropylenetriol with a molecular weight of approximately 3,000 as an initiator, polymerization of propylene oxide was carried out using a zinc hexacyanocobaltate grime complex catalyst to obtain polypropylene oxide with a number average molecular weight of approximately 19,000 (polystyrene-equivalent molecular weight measured using a Tosoh HLC-8120GPC liquid delivery system, a Tosoh TSK-GEL H type column, and THF as the solvent). Subsequently, a methanol solution of NaOMe in an amount equivalent to 1.2 times the hydroxyl group of this hydroxyl-terminated polypropylene oxide was added, and the methanol was removed by distillation. Furthermore, allyl chloride was added to convert the terminal hydroxyl groups to allyl groups. Thus, polypropylene oxide with allyl groups at the ends and a number average molecular weight of approximately 19,000 was obtained. To 100 parts by weight of the obtained unpurified allyl-terminated polypropylene oxide, 300 parts by weight of n-hexane and 300 parts by weight of water were mixed and stirred. The water was then removed by centrifugation, and another 300 parts by weight of water was mixed and stirred into the resulting hexane solution. The water was removed again by centrifugation, and the hexane was removed by vacuum defloration to obtain purified allyl-terminated polypropylene oxide (hereinafter referred to as allyl polymer). To 100 parts by weight of the obtained allyl polymer, 0.7 molar equivalents of methyldimethoxysilane were reacted with 150 ppm of an isopropanol solution of a platinum vinylsiloxane complex with a platinum content of 3 wt% as a catalyst at 90°C for 5 hours to obtain methyldimethoxysilyl-terminated polypropylene oxide (A-3). There were approximately 0.7 methyldimethoxysilyl groups per polymer chain end.

[0128] (Synthesis Example 3 (A-3)) A trimethoxysilyl-terminated polyoxypropylene polymer (A-3) was obtained in the same manner as in Synthesis Example 1, except that 0.6 molar equivalents of trimethoxysilane were used. The number of trimethoxysilyl groups was approximately 0.6 per polymer chain end.

[0129] (Synthesis Example 4 (A-4)) Using polyoxypropylenediol with a molecular weight of approximately 2,000 as an initiator, propylene oxide was polymerized using a zinc hexacyanocobaltate grime complex catalyst to obtain polypropylene oxide with a number average molecular weight of approximately 28,500. Subsequently, 1.0 equivalent of a methanol solution of NaOMe was added to the hydroxyl groups of this hydroxyl-terminated polypropylene oxide, and the methanol was distilled off at 140°C. Then, 1.0 equivalent of allyl glycidyl ether was added and the reaction was carried out for 2 hours. Furthermore, allyl chloride was added to convert the terminal hydroxyl groups to allyl groups. As a result, an allyl polymer with multiple allyl groups at the ends and a number average molecular weight of approximately 28,500 was obtained. The allyl polymer was purified using the same procedure as in Synthesis Example 1. To 100 parts by weight of the obtained allyl polymer, a 150 ppm isopropanol solution of a platinum vinylsiloxane complex with a platinum content of 3 wt% was used as a catalyst to react with 0.8 molar equivalents of trimethoxysilane relative to the total allyl groups contained in the allyl polymer at 90°C for 5 hours to obtain trimethoxysilyl-terminated polypropylene oxide (A-4). The number of trimethoxysilyl groups was approximately 1.5 per polymer chain end.

[0130] (Synthesis Example 5 (A-5)) Using a polyoxypropylene triol with a molecular weight of approximately 4,500 as an initiator, propylene oxide was polymerized using a zinc hexacyanocobaltate glyme complex catalyst to obtain polyoxypropylene with a number average molecular weight of approximately 24,600. Subsequently, 1.2 molar equivalents of sodium methoxide in a 28% methanol solution were added to the hydroxyl groups of this hydroxyl-terminated polypropylene oxide. After removing methanol by vacuum defoliation, an additional 1.5 molar equivalents of allyl chloride were added to the hydroxyl groups of the polymer to convert the terminal hydroxyl groups into allyl groups. Thus, polyoxypropylene with allyl groups at the ends was obtained. The allyl polymer was purified using the same procedure as in Synthesis Example 1. To 100 parts by weight of the obtained allyl polymer, 2.1 molar equivalents of trimethoxysilane relative to the total allyl groups contained in the allyl polymer were reacted with 150 ppm of an isopropanol solution of a platinum vinylsiloxane complex with a platinum content of 3 wt% as a catalyst at 90°C for 5 hours to obtain trimethoxysilyl-terminated polypropylene oxide (A-5). The number of trimethoxysilyl groups was approximately 0.7 per polymer chain end.

[0131] (Synthesis Example 6 (A-6)) Using polyoxypropylene glycol with a number average molecular weight of approximately 4,500 as an initiator, propylene oxide was polymerized with a zinc hexacyanocobaltate-grime complex catalyst to obtain polyoxypropylene with a number average molecular weight of 27,900 having hydroxyl groups at both ends. To 100 parts by weight of the obtained polymer having hydroxyl groups at both ends, 30 ppm of a bismuth(III) 2-ethylhexanoic acid solution (Bi: 25%) and 0.95 molar equivalents of (3-isocyanatopropyl)trimethoxysilane relative to the hydroxyl groups of the polymer were added, and a urethane reaction was carried out on the hydroxyl groups of the polymer to obtain a linear silyl group-containing polyoxypropylene (A-6) without branching points. The number of trimethoxysilyl groups was approximately 0.9 per polymer chain end.

[0132] (Synthesis Example 7 (A-7)) A solution of 2,2'-azobis(2-methylbutyronitrile) (1.8 parts by weight) was added dropwise over 5 hours to a 2-butanol solution of the monomer mixture below heated to 105°C, and then "post-polymerization" was carried out for 1 hour to obtain (meth)acrylic acid ester copolymer (a-1). Monomer mixture composition: methyl methacrylate (65 parts by weight), 2-ethylhexyl acrylate (25 parts by weight), γ-methacryloxypropyltrimethoxysilane (10 parts by weight), 3-mercaptopropyltrimethoxysilane (7 parts by weight). Polymer (A-5) obtained in Synthesis Example 5 and polymer (a-1) were mixed in a solids weight ratio of 60 / 40, and then the solvent was removed by distillation to obtain polymer (A-7).

[0133] (Synthesis Example 8 (A-8)) Polymer (A-4) and polymer (a-1) obtained in Synthesis Example 4 were mixed in a solids weight ratio of 60 / 40, and then the solvent was removed by distillation to obtain polymer (A-8).

[0134] (Synthesis Example 9 (A-9)) 55.4 parts by weight of isobutyl alcohol were placed in a four-necked flask equipped with a stirrer and heated to 105°C under a nitrogen atmosphere. A mixed solution of 78.3 parts by weight of methyl methacrylate, 6.7 parts by weight of butyl acrylate, 15.0 parts by weight of stearyl methacrylate, 10.9 parts by weight of (3-mercaptopropyl)trimethoxysilane, and 0.35 parts by weight of 2,2'-azobis(2-methylbutyronitrile) dissolved in 16.3 parts by weight of isobutyl alcohol was added dropwise over 3.5 hours. Polymerization was then carried out at 105°C for 2 hours to obtain an isobutyl alcohol solution (60% by weight) of a (meth)acrylic acid ester polymer (a-2) with a number average molecular weight of 1,850 and a weight average molecular weight of 3,400.

[0135] Polymer (A-4) and polymer (a-2) obtained in Synthesis Example 4 were mixed in a solids weight ratio of 70 / 30, and then the solvent was removed by distillation to obtain polymer (A-9).

[0136] (Example 1) One-component curable composition <Main component preparation> For polymer (A-1), the following amounts are used for each component (unless otherwise specified, the unit is parts by weight; the same applies hereinafter): colloidal calcium carbonate (manufactured by Shiraishi Industries Co., Ltd., trade name: Shiratsuka CCR), heavy calcium carbonate (manufactured by Shiraishi Calcium Co., Ltd., trade name: Whiteon SB), pigment (manufactured by Ishihara Industries Co., Ltd., trade name: Typeque R820), plasticizer (manufactured by J-Plus Co., Ltd., trade name: DINP, diisononyl phthalate), and thixotropic agent (manufactured by ARKEMA, trade name: Crayvallac) SLT, an antioxidant (BASF, trade name: Irganox 1010), a UV absorber (BASF, trade name: Tinuvin 571), and a light stabilizer (BASF, trade name: Tinuvin 770) were added and mixed using a spatula. The mixture was then dispersed by passing it through a three-roll mill three times to obtain the main component. After this, a Karl Fischer moisture meter (EBU-610: Kyoto Electronics Manufacturing Co., Ltd.) was used to determine the concentration of Aquamicron titration solution SS 3 mg (potency 2.5-3.5 mgH). ２ 0 / mL (manufactured by Mitsubishi Chemical Corporation), and Aquamicron dehydrating agent CM (moisture content 0.3 mgH) ２ The water content in the main component was measured using a device manufactured by Mitsubishi Chemical Corporation (for use with a water content of 0 / mL or less).

[0137] <Dehydration Process> To the main component described above, the amounts of Dynasylan VTMO (alkoxysilane-containing dehydrating agent (C): vinyltrimethoxysilane, manufactured by Evonik) and DBU (amidine structure-containing compound (B): 1,8-diazabicyclo[5.4.0]-7-undecene, manufactured by Tokyo Chemical Industry Co., Ltd.) listed in Table 1 were added, and dehydration was carried out by stirring at 60°C under atmospheric pressure for 30 minutes using a planetary mixer. After this, a Karl Fischer moisture meter (EBU-610: manufactured by Kyoto Electronics Manufacturing Co., Ltd.) was used to determine the concentration of Aquamicron titration solution SS 3 mg (potency 2.5-3.5 mgH). ２ 0 / mL (manufactured by Mitsubishi Chemical Corporation), and Aquamicron dehydrating agent CM (moisture content 0.3 mgH) ２ The moisture content after the dehydration process was measured using a device manufactured by Mitsubishi Chemical Corporation (for use with a concentration of 0 / mL or less).

[0138] <Devolatilization Process> After the dehydration process, defoliation was carried out for 30 minutes under room temperature and reduced pressure to remove unreacted Dynasylan VTMO with methanol.

[0139] <Mixing Process> Next, the amounts of Dynasylan VTMO (alkoxysilane-containing dehydrating agent (C')) and Dynasylan DAMO (adhesion-imparting agent, 3-(2-aminoethylamino)propyltrimethoxysilane, manufactured by Evonik) listed in Table 1 were added and mixed. The resulting curable composition was filled into a moisture-proof cartridge and sealed to obtain a one-component curable composition.

[0140] (Comparative Example 1) A one-component curable composition was obtained in the same manner as in Example 1, except that polymer (A-2) was used instead of polymer (A-1).

[0141] (Evaluation) (Skinning time (curing properties)) The one-component curable composition was stored for 7 days in an atmosphere of 23°C and 50% relative humidity. The time it took to fill a mold with a thickness of approximately 5 mm with the obtained curable composition using a spatula and to smooth the surface was defined as the curing start time. The time it took for the composition to no longer adhere to the spatula when touched was measured. The obtained results are shown in Table 1 as "skinning time" (curing properties).

[0142]

[0143] (Evaluation Results) The curable composition of polymer (A-1) having a trimethoxysilyl group (Example 1) showed faster curing properties compared to polymer (A-2) having a methyldimethoxysilyl group (Comparative Example 1).

[0144] (Example 2) A one-component curable composition was prepared in the same manner as in Example 1, except that the stirring time in the dehydration step was extended to 60 minutes.

[0145] (Comparative Example 2) A one-component curable composition was prepared in the same manner as in Example 1, except that the amount of Dynasylan VTMO (alkoxysilane-containing dehydrating agent (C)) added in the dehydration step was changed to 10 by weight, and Dynasylan VTMO (alkoxysilane-containing dehydrating agent (C')) was not added in the mixing step.

[0146] (Comparative Example 3) A one-component curable composition was prepared in the same manner as in Comparative Example 2, except that the stirring time in the dehydration step was extended to 60 minutes. The skinning time (curing properties) was evaluated in the same manner as in Example 1. The results obtained are shown in Table 2.

[0147] (Dumbbell Tensile Properties) Under constant temperature and humidity conditions of 23°C and 50% relative humidity, the curable composition was filled into a 3 mm thick sheet-like mold. After curing at 23°C and 50% RH for 3 days, it was cured in a 50°C dryer for 4 days to obtain a sheet-like cured material. The obtained cured material was punched out into a No. 3 dumbbell shape according to JIS K 6251, and a tensile test (tensile speed 200 mm / min) was performed using an autograph to measure the stress at 50% elongation, stress at 100% elongation, stress at fracture, and elongation at fracture. The results are shown in Table 2.

[0148] (Adhesion) The curable composition was applied to various substrates shown in Table 2 to ensure close adhesion, and cured for 7 days under constant temperature and humidity conditions of 23°C and 50% relative humidity. A 90° hand peel test was performed on the resulting cured material, and the fracture state was observed. The fracture state was defined as cohesive fracture (failure in the curable composition portion) as CF and interfacial fracture (peeling at the interface between the curable composition and the substrate) as AF, and confirmed visually. The results are shown in Table 2.

[0149]

[0150] (Evaluation Results) In the dehydration step, an alkoxysilane-containing dehydrating agent (C) and an amidine structure-containing compound (B) were added, the mixture was stirred at 60°C and atmospheric pressure, followed by defloration under reduced pressure, and then the alkoxysilane-containing dehydrating agent (C') was added to prepare the curable compositions (Examples 1 and 2). These compositions showed faster curing compared to curable compositions (Comparative Examples 1 and 2) prepared by adding twice the amount of alkoxysilane-containing dehydrating agent in the dehydration step but not in the mixing step. Furthermore, the curable compositions (Examples 1 and 2) exhibited good tensile properties and adhesive properties.

[0151] (Comparative Example 4) A one-component curable composition was prepared in the same manner as in Example 1, except that the alkoxysilane-containing dehydrating agent (C) was volatilized at 60°C under reduced pressure without adding DBU (amidine structure-containing compound (B)) in the dehydration step, and DBU was added in the mixing step. Measurements were performed in the same manner as in Example 1. The results obtained are shown in Table 3.

[0152]

[0153] (Evaluation Results) The curable composition prepared by adding an alkoxysilane-containing dehydrating agent (C) and an amidine structure-containing compound (B) and performing dehydration (Example 1) showed faster curing properties compared to the curable composition prepared by using only the alkoxysilane-containing dehydrating agent (C) and then adding the amidine structure-containing compound (B) (Comparative Example 4).

[0154] (Example 3) A one-component curable composition was prepared in the same manner as in Example 1, except that the amount of Dynasylan VTMO (alkoxysilane-containing dehydrating agent (C)) added in the dehydration step was changed to 3 parts by weight. Measurements were performed in the same manner as in Example 1. The results obtained are shown in Table 4.

[0155]

[0156] (Evaluation Results) The curable composition of Example 3 showed good curability, tensile properties, and adhesive properties.

[0157] (Examples 4 and 5) As shown in Table 5, a one-component curable composition was prepared in the same manner as in Example 1, except that Dynasilan AMMO (adhesion fertilizer, 3-aminopropyltrimethoxysilane, manufactured by Evonik) or Dynasilan 1146 (adhesion fertilizer, aminosilane oligomer, manufactured by Evonik) was used instead of Dynasilan DAMO in the mixing step. Measurements were performed in the same manner as in Example 1. The obtained results are shown in Table 5.

[0158]

[0159] (Evaluation Results) The curable compositions of Examples 4 and 5 showed good curability, tensile properties, and adhesive properties.

[0160] (Example 6) A one-component curable composition was prepared in the same manner as in Example 1, except that the organic polymer (A-3) listed in Table 6 was used.

[0161] (Comparative Example 5) A one-component curable composition was prepared in the same manner as in Comparative Example 4, except that the organic polymer (A-3) listed in Table 6 was used. Measurements were performed in the same manner as in Example 1. The results obtained are shown in Table 6.

[0162]

[0163] (Evaluation Results) The curable composition (Example 6) prepared by dehydrating with an alkoxysilane-containing dehydrating agent (C) and an amidine structure-containing compound (B) showed faster curing properties compared to the curable composition (Comparative Example 5) prepared by dehydrating using only the alkoxysilane-containing dehydrating agent (C) and then adding the amidine structure-containing compound (B). Furthermore, the curable composition (Example 6) also exhibited good tensile properties and adhesive properties.

[0164] (Examples 7-9) A one-component curable composition was prepared in the same manner as in Example 1, except that the organic polymer (A-4) and adhesion promoter listed in Table 7 were used.

[0165] (Comparative Example 6) A one-component curable composition was prepared in the same manner as in Comparative Example 4, except that the organic polymer (A-4) listed in Table 7 was used. Measurements were performed in the same manner as in Example 1. The results obtained are shown in Table 7.

[0166]

[0167] (Evaluation Results) The curable compositions prepared by adding an alkoxysilane-containing dehydrating agent (C) and an amidine structure-containing compound (B) and performing dehydration (Examples 7-9) showed faster curing compared to the curable composition prepared by using only the alkoxysilane-containing dehydrating agent (C) and then adding the amidine structure-containing compound (B) (Comparative Example 6). Furthermore, the curable compositions (Examples 7-9) also exhibited good tensile properties and adhesive properties.

[0168] (Examples 10-12) A one-component curable composition was prepared in the same manner as in Example 1, except that the organic polymer (A-5) and adhesion promoter listed in Table 8 were used.

[0169] (Comparative Example 7) A one-component curable composition was prepared in the same manner as in Comparative Example 4, except that the organic polymer (A-5) listed in Table 8 was used. Measurements were performed in the same manner as in Example 1. The results obtained are shown in Table 8.

[0170]

[0171] (Evaluation Results) The curable compositions prepared by adding an alkoxysilane-containing dehydrating agent (C) and an amidine structure-containing compound (B) and performing dehydration (Examples 10-12) showed faster curing compared to the curable composition prepared by using only the alkoxysilane-containing dehydrating agent (C) and then adding the amidine structure-containing compound (B) (Comparative Example 7). Furthermore, the curable compositions (Examples 10-12) also showed good tensile properties and adhesive properties.

[0172] (Examples 13 and 14) A one-component curable composition was prepared in the same manner as in Example 1, except that the organic polymer (A-6) and adhesion promoter listed in Table 9 were used.

[0173] (Comparative Example 8) A one-component curable composition was prepared in the same manner as in Comparative Example 4, except that the organic polymer (A-6) listed in Table 9 was used. Measurements were performed in the same manner as in Example 1. The results obtained are shown in Table 9.

[0174]

[0175] (Evaluation Results) The curable compositions prepared by adding an alkoxysilane-containing dehydrating agent (C) and an amidine structure-containing compound (B) and performing dehydration (Examples 13 and 14) showed faster curing compared to the curable composition prepared by using only the alkoxysilane-containing dehydrating agent (C) and then adding the amidine structure-containing compound (B) (Comparative Example 8). Furthermore, the curable compositions (Examples 13 and 14) also exhibited good tensile properties and adhesive properties.

[0176] (Examples 15-17) One-component curable compositions were prepared in the same manner as in Example 1, except that organic polymers (A-7), (A-8), or (A-9) listed in Table 10 were used. Measurements were performed in the same manner as in Example 1. The results obtained are shown in Table 10.

[0177]

[0178] (Evaluation Results) The curable compositions of Examples 15 to 17 all exhibited good curability, tensile properties, and adhesive properties.

Claims

1. The following general formula (1): -SiX ３ (1) A method for producing a curable composition containing an organic polymer (A) having a reactive silicon group represented by the formula (wherein X is the same or different, representing a hydroxyl group or a hydrolyzable group), comprising: a dehydration step of adding an amidine structure-containing compound (B) and an alkoxysilane-containing dehydrating agent (C) to a system containing the organic polymer (A), and stirring at 10 to 90°C and under pressure in which the alkoxysilane-containing dehydrating agent (C) does not substantially volatilize; a defloration step of deflorating the volatile components contained in the system containing the organic polymer (A) after the dehydration step under reduced pressure; and a mixing step of mixing an alkoxysilane-containing dehydrating agent (C') to the system containing the organic polymer (A) after the defloration step, A method for producing a curable composition, wherein the amount of the alkoxysilane-containing dehydrating agent (C) added in the dehydration step is such that, with respect to the 100 mol% water content of the system containing the organic polymer (A) before the dehydration step, the total number of moles of alkoxy groups directly attached to silicon atoms in the alkoxysilane-containing dehydrating agent (C) is 100 mol% or more and 300 mol% or less.

2. The manufacturing method according to claim 1, wherein the stirring time in the dewatering step is 20 minutes or more.

3. The manufacturing method according to claim 1, wherein the temperature in the dehydration step is 40°C or higher.

4. The manufacturing method according to claim 1, wherein the amount of the amidine structure-containing compound (B) added is 0.2 parts by weight or more per 100 parts by weight of the organic polymer (A).

5. The amidine structure-containing compound (B) is represented by the following general formula (2): R ２ N = CR ３ -NR ４ ２ (2) (In the formula, R ２ , R ３ , and R ４ are the same or different and each represents a hydrogen atom, or a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. Two R ４ may be the same or different. Any two or more of R ２ , R ３ , and two R ４ may combine to form a cyclic structure.) The production method according to claim 1.

6. The manufacturing method according to claim 1, wherein the alkoxysilane-containing dehydrating agent is added only twice in total, during the dehydration step and the mixing step.

7. The manufacturing method according to claim 1, wherein an adhesion promoter is further mixed in the mixing step.

8. The curable composition is of the following general formula (3): Ti(OR ５ ) ｄ Y ４－ｄ (3) (wherein, R ５ The method for producing the product according to claim 1, wherein the titanium compound represented by (D) (where ) represents a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms, Y represents a chelate coordination compound, and d represents 0 or an integer from 1 to 4) is not contained.

9. The manufacturing method according to claim 1, wherein the amount of the alkoxysilane-containing dehydrating agent (C') added is 1 to 15 parts by weight per 100 parts by weight of the organic polymer (A).

10. The manufacturing method according to claim 1, wherein the alkoxysilane-containing dehydrating agent (C) or (C') is a vinyl-type unsaturated group-containing silane.

11. The manufacturing method according to claim 10, wherein the alkoxysilane-containing dehydrating agent (C) or (C') is vinyltrimethoxysilane.

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