Curable resin composition and method for producing the same

Abstract

The present invention provides a curable resin composition containing a vinyl polymer having a reactive silyl group, which exhibits excellent weather resistance and good extensibility. [Solution] A curable resin composition comprising a vinyl polymer (A), wherein the vinyl polymer (A) has a main chain having repeating units of polymerizable vinyl monomers and reactive silyl groups bonded to the vinyl polymer main chain via a urethane structure, and the vinyl polymer (A) is a polymer obtained by silylation of the plurality of hydroxyl groups of a vinyl polymer (a) having a plurality of hydroxyl groups and a weight-average molecular weight / hydroxyl value of more than 4,000.

Description

[Technical Field]

[0001] This disclosure relates to a curable resin composition and a method for producing the same. [Background technology]

[0002] In recent years, with the increasing need to extend the lifespan and durability of buildings, similar properties are required of sealing materials, leading to increased demand for polymers (polymers) for this purpose. Vinyl polymers having reactive silyl groups at the ends of their main chains are widely used as building sealants due to their excellent balance of properties.

[0003] Patent Document 1 describes an alkyl (meth)acrylate polymer. This alkyl (meth)acrylate polymer is characterized by having a weight-average molecular weight (Mw) of 30,000 to 150,000 as measured by gel permeation chromatography (GPC), a number-average molecular weight (Mn) of 20,000, 1.1 to 3.0 methyldimethoxysilyl groups per molecule by weight, more than 0.5 methyldimethoxysilyl groups in the side chains of the molecular chain, and more than 0.5 methyldimethoxysilyl groups at the end of the molecular chain.

[0004] Patent Document 2 describes a curable resin composition. This curable resin composition contains a vinyl polymer (A), a vinyl monomer (B), and a curing catalyst (C). The vinyl polymer (A) has reactive silyl groups at the ends and side chains of its molecular chain, the molecular chain has repeating units made of polymerizable vinyl monomers, and on average per molecule, the number of reactive silyl groups is greater than 1, the number of reactive silyl groups at the ends is greater than 0.5, the number of reactive silyl groups on the side chains is greater than 0.5, the weight-average molecular weight is 30,000 to 110,000, the number-average molecular weight is 9,000 to 40,000, and the glass transition temperature is -100 to -10 degrees Celsius. The vinyl monomer (B) does not have reactive silyl groups, its molecular chain has repeating units made of polymerizable vinyl monomers, and its weight-average molecular weight is 20,000 or less. The vinyl polymer (A) has repeating units made of polymerizable vinyl monomers and has specific reactive silyl groups at the ends of its molecular chains. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2019 / 039537 [Patent Document 2] International Publication No. 2019 / 187701 [Overview of the project] [Problems that the invention aims to solve]

[0006] Among the reactive polymers used as sealants, urethane polymers with a polyether main chain may not have sufficient resistance to light and heat. Such polymers may be unsuitable for use as sealants, especially in applications exposed to the elements. In particular, urethane polymers with a polypropylene glycol (PPG) backbone may not achieve sufficient weather resistance.

[0007] In contrast, polymers having an acrylic backbone and reactive silyl groups (silylated vinyl polymers) exhibit excellent weather resistance. However, conventional silylated vinyl polymers, when having reactive silyl groups at both ends of the main chain, sometimes resulted in excessively high manufacturing costs.

[0008] The present invention aims to provide a curable resin composition containing a vinyl polymer having a reactive silyl group, which can provide a cured product exhibiting good weather resistance and good mechanical properties, while potentially being more cost-effective than conventional silylated vinyl polymer-containing compositions. [Means for solving the problem]

[0009] One aspect of the present invention for solving the above problems relates to the curable resin compositions of the following <Aspect 1> to <Aspect 5>. <Aspect 1> A curable resin composition containing a vinyl polymer (A), The vinyl polymer (A) has a main chain having repeating units derived from a polymerizable vinyl monomer, and reactive silyl groups bonded to the main chain via a urethane structure. The vinyl polymer (A) is A curable resin composition, which is a polymer obtained by silylation of the multiple hydroxyl groups of a vinyl polymer (a) having multiple hydroxyl groups and a weight-average molecular weight / hydroxyl value of more than 4,000. <Aspect 2> The curable resin composition according to embodiment 1, wherein the vinyl polymer (A) has a weight-average molecular weight Mw of 10,000 or more. <Aspect 3> The curable resin composition according to embodiment 1 or 2, wherein the vinyl polymer (A) has a weight-average molecular weight to number-average molecular weight ratio (Mw / Mn) of 4.0 or more. <Aspect 4> The curable resin composition according to embodiment 1 or 2, wherein the vinyl polymer (A) has the reactive silyl group at least at both ends of the main chain, or has the reactive silyl group at at least one end of the main chain and the reactive silyl group on side chains located at random positions on the main chain. <Aspect 5> A method for producing a curable resin composition, The steps include: preparing a vinyl polymer (A) having a main chain having repeating units derived from a polymerizable vinyl monomer and reactive silyl groups bonded to the main chain via a urethane structure by silylation of the multiple hydroxyl groups of a vinyl polymer (a) having multiple hydroxyl groups and a weight-average molecular weight / hydroxyl value of more than 4,000; The step includes mixing the vinyl polymer (A) with other components. A method for producing a curable resin composition. [Effects of the Invention]

[0010] According to the present invention, a curable resin composition containing a vinyl polymer having a reactive silyl group is provided, which can yield a cured product exhibiting good weather resistance and good mechanical properties, while potentially being more cost-effective in manufacturing than conventional silylated vinyl polymer-containing compositions.

[0011] The applications of the curable resin composition according to the present invention are not particularly limited, but it is especially suitable for sealing and waterproofing applications in outdoor environments. [Modes for carrying out the invention]

[0012] <<Curable resin composition>> The curable resin composition according to the present invention comprises a vinyl polymer (A), The vinyl polymer (A) has a main chain having repeating units derived from a polymerizable vinyl monomer, and reactive silyl groups bonded to the main chain via a urethane structure. The vinyl polymer (A) is a polymer obtained by silylating a plurality of hydroxyl groups of a vinyl polymer (a) having a plurality of hydroxyl groups and having a weight average molecular weight / hydroxyl value of more than 4,000.

[0013] The inventors of the present invention have found that in a vinyl polymer having a main chain having repeating units derived from a polymerizable vinyl monomer and a reactive silyl group bonded to the vinyl polymer main chain via a urethane structure, by limiting the number of silyl groups and the average molecular weight to a specific range, a curable resin composition capable of providing a cured product having sufficient weather resistance and exhibiting improved mechanical properties (particularly elongation) can be provided, and thus the present invention has been achieved.

[0014] According to the present invention, a curable resin composition particularly suitable for a sealing material used in an outdoor environment can be provided. The curable resin composition according to the present invention exhibits good weather resistance as compared with a conventional curable resin composition containing a silylated polymer having a main chain having repeating units derived from polypropylene glycol (PPG). Further, the curable resin composition according to the present invention exhibits good elongation because the content ratio of the silyl groups of the vinyl polymer (A) is limited to a specific range. Although there is no intention to be limited by theory, it is considered that by setting the content ratio of the silyl groups within a certain range, the distance between crosslinking points is limited to a specific range, and sufficient extensibility is ensured. According to the present invention, even if the vinyl polymer does not have reactive silyl groups at both ends of the main chain, good extensibility can be obtained, which can be advantageous in terms of production cost as compared with a conventional composition containing a silylated vinyl polymer.

[0015] In addition, the curable resin composition according to the present invention can have a relatively low molecular weight required to obtain sufficient extensibility as compared with a conventional curable resin composition containing a vinyl polymer in which a reactive silyl group is not bonded to the main chain via a urethane bond. Due to the low molecular weight of the polymer contained, the curable resin composition according to the present invention can have a relatively low viscosity and can have more excellent workability.

[0016] The present invention will be described in detail below.

[0017] In this specification, numerical ranges expressed using "~" mean a range that includes the numbers before and after "~" as the lower and upper limits. In this specification, the method of manufacturing each component is not particularly limited. For example, conventionally known methods are included. In this specification, unless otherwise specified, each component may use the substances corresponding to that component individually or in combination of two or more. If a component contains two or more substances, the content of the component means the total content of the two or more substances.

[0018] In this specification, (meth)acrylate refers to acrylate or methacrylate. (meth)acrylic refers to acrylic or methacrylic. Poly(meth)acrylate refers to polyacrylate, polymethacrylate, or a copolymer of acrylate and methacrylate.

[0019] <Vinyl polymer (A)> The vinyl polymer (A) has a main chain having repeating units derived from a polymerizable vinyl monomer and reactive silyl groups bonded to the main chain via a urethane structure. The shape of the main chain of the vinyl polymer (A) is not particularly limited, but may be, for example, linear, or in a form in which multiple (particularly two) molecular chains are linked by crosslinking or the like. The content of the vinyl polymer (A) in the curable resin composition is not particularly limited, but may be, for example, 5 parts by mass or more, 10 parts by mass or more, or 20 parts by mass or more, and / or 95 parts by mass or less, 90 parts by mass or less, or 80 parts by mass or less, per 100 parts by mass of the curable resin composition. In one preferred embodiment, the content of the vinyl polymer (A) is 25 to 70 parts by mass per 100 parts by mass of the curable resin composition.

[0020] Vinyl polymer (A) has a structure obtained by silylation of the multiple hydroxyl groups of vinyl polymer (a), which has multiple hydroxyl groups and a weight-average molecular weight / hydroxyl value of more than 4,000. The multiple hydroxyl groups of vinyl polymer (a) may be silylated by one compound, or by a combination of two or more compounds.

[0021] More specifically, for example, vinyl polymer (A) has a structure obtained by the reaction of multiple hydroxyl groups of vinyl polymer (a) having multiple hydroxyl groups with a weight-average molecular weight / hydroxyl value of more than 4,000 with the isocyanate groups of an isocyanate silane compound. In this case, for example, vinyl polymer (A) according to the present invention may be a polymer obtained by the reaction of a polyacrylic polyol with an isocyanate silane compound.

[0022] For example, vinyl polymer (A) has a structure obtained when a vinyl polymer (a) having multiple hydroxyl groups with a weight-average molecular weight / hydroxyl value of more than 4,000 reacts with one isocyanate group of a diisocyanate compound to form an intermediate, in which the remaining isocyanate groups derived from the diisocyanate compound further react with an aminosilane compound to undergo aminosilylation. That is, for example, it may have a structure obtained by isocyanating the hydroxyl groups with a diisocyanate compound and then alkoxysilylation with an aminosilane compound.

[0023] (Main chain) The main chain of vinyl polymer (A) has repeating units derived from polymerizable vinyl monomers. The repeating units comprising polymerizable vinyl monomers that constitute the main chain are not particularly limited as long as they are repeating units of compounds having carbon-carbon double bonds. For example, they may be olefin monomers such as ethylene; (meth)acrylic monomers such as (meth)acrylate, (meth)acrylamide, and (meth)acrylic acid; hydroxyl group-containing (meth)acrylic monomers such as hydroxyalkyl (meth)acrylate; or repeating units of aromatic vinyl monomers such as styrene.

[0024] The main chain of vinyl polymer (A) has repeating units made of polymerizable vinyl monomers and may be substantially hydrocarbon. Here, "substantially" means that the molecular chain of vinyl polymer (A) may further contain repeating units other than -[CC]-, but the -[CC]- content is 50% by mass or more of the total repeating units of vinyl polymer (A). Preferably, the -[CC]- content is 80% by mass or more, and more preferably 90% by mass or more, of the total repeating units of vinyl polymer (A).

[0025] Polymerizable vinyl monomers may be a combination of hydroxyalkyl (meth)acrylate and alkyl (meth)acrylate ester, from the viewpoint of superior weather resistance, curability, or handling properties. The hydrocarbon groups constituting the ester portion of these monomers may be, for example, aliphatic hydrocarbon groups (linear, branched, or cyclic), aromatic hydrocarbon groups, or a combination thereof. From the viewpoint of superior weather resistance, curability, or handling properties, the ester residues (hydrocarbon groups constituting the ester) in these monomers preferably have hydrocarbon groups having 1 to 18 carbon atoms (particularly 1 to 12). The hydrocarbon groups having 1 to 18 carbon atoms (particularly 1 to 12) may be, for example, aliphatic hydrocarbon groups such as propyl, butyl, pentyl, hexyl, octyl, 2-ethylhexyl, isononyl, and lauryl groups; or they may be aliphatic hydrocarbon groups with a hydrogen atom removed from these, with a valency of 2 or higher.

[0026] Alkyl (meth)acrylates may include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, lauryl (meth)acrylate, myristyl (meth)acrylate, isomiristyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, isobornyl (meth)acrylate, etc. These may be used individually or in combination of two or more.

[0027] The hydroxyalkyl (meth)acrylate may be, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, or 4-hydroxybutyl (meth)acrylate. These may be used individually or in combination of two or more.

[0028] The vinyl polymer (A) may contain structural units derived from polymerizable vinyl monomers in its main chain in an amount of 50% or more by mass, 60% or more by mass, 70% or more by mass, or 80% or more by mass, preferably 90% or more by mass, more preferably 95% or more by mass, and even more preferably 98% or more by mass.

[0029] The vinyl polymer (A) of the present invention may contain structural units derived from other copolymerizable monomers, and may also contain structural units derived from polymerizable monomers other than polymerizable vinyl monomers. The content of such structural units derived from other monomers may be 50% by mass or less, 40% by mass or less, 30% by mass or less, or 20% by mass or less of the total structural units constituting the polymer, preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 2% by mass or less.

[0030] The vinyl polymer (A) may contain structural units derived from the polymerization initiator. For example, when a hydroxyl group-containing initiator is used as the polymerization initiator, a hydrogen group is introduced to one end. In this case, the vinyl polymer (A) has a structure in which a reactive silyl group is bonded to one end of the main chain via a urethane structure. Examples of hydroxyl group-containing initiators include hydroxyethyl-2-bromopropionate.

[0031] (Urethane structure) The reactive silyl group is bonded to the main chain of the vinyl polymer (A) via a urethane structure. The urethane structure is formed, for example, by the reaction of an isocyanate group and a hydroxyl group.

[0032] (Reactive silyl group) The vinyl polymer (A) has reactive silyl groups bonded to the vinyl polymer main chain via a urethane structure.

[0033] Reactive silyl groups may be present at least at the ends or side chains of the main chain of vinyl polymer (A). In one embodiment, reactive silyl groups may be present at at least both ends of the main chain. In another embodiment, reactive silyl groups may be located at at least one end of the main chain of vinyl polymer (A) and also on the side chains of vinyl polymer (A). If reactive silyl groups are present on the side chains of vinyl polymer (A), those side chains may be located at random positions on the main chain. For example, vinyl polymer (A) may have reactive silyl groups at at least one end of the main chain and reactive silyl groups on side chains located at random positions on the main chain. Note that "randomly located" on the main chain means that the side chains are located at unspecified (randomly selected) positions on the main chain.

[0034] The reactive silyl group may be included, for example, as part of the repeating units that make up the main chain of the vinyl polymer (A).

[0035] The reactive silyl group is not particularly limited as long as it is a reactive group having a silicon atom. For example, the reactive silyl group may be a silyl group in which one to three hydrolyzable groups are bonded to one silicon atom. From the viewpoint of superior weather resistance, curability, and workability, the reactive silyl group of vinyl polymer (A) is preferably a silyl group in which two or three hydrolyzable groups are bonded to one silicon atom. The hydrolyzable group may be, for example, hydrogen, halogen atom, alkoxy group, acyl oxide group, ketoximate group, amino group, amide group, acid amide group, aminooxy group, mercapto group, or alkenyl oxide group. Among these, alkoxy groups are preferred.

[0036] From the viewpoint of superior storage stability, curability, and / or workability, alkyldialkoxysilyl groups, trialkoxysilyl groups, or combinations thereof are preferred as the reactive silyl group. In particular, the reactive silyl group is a methyldimethoxysilyl group, a trimethoxysilyl group, or a combination thereof.

[0037] In alkyldialkoxysilyl groups and trialkoxysilyl groups (particularly methyldimethoxysilyl and trimethoxysilyl groups), the other hydrocarbon group that can be bonded to the silicon atom is not particularly limited and may be, for example, an alkyl group (particularly a methyl or ethyl group).

[0038] The vinyl polymer (A) may be a mixture of polymers having reactive silyl groups at various positions in the main chain. For example, the vinyl polymer (A) may be a mixture of (i) vinyl polymers having reactive silyl groups at the ends (one or both ends) of the main chain, (ii) vinyl polymers having reactive silyl groups in the side chains of the main chain, and (iii) vinyl polymers having reactive silyl groups at the ends (one or both ends) of the main chain and in the side chains.

[0039] (average molecular weight) The weight-average molecular weight (Mw) of vinyl polymer (A) may be 10,000 or more, 15,000 or more, 20,000 or more, 25,000 or more, or 30,000 or more, and / or 70,000 or less, 60,000 or less, 55,000 or less, or 50,000 or less. The weight-average molecular weight of vinyl polymer (A) is preferably 15,000 to 60,000, more preferably 20,000 to 50,000. Having the weight-average molecular weight within the above range may result in superior weather resistance, curability, and handling properties.

[0040] The ratio of the weight-average molecular weight to the number-average molecular weight (Mw / Mn) of the vinyl polymer (A) may be 2.0 or higher, or more preferably 3.0 or higher, and more preferably 4.0 or higher. In particular, the Mw / Mn of the vinyl polymer (A) may be 3.6 or higher, 3.8 or higher, 4.0 or higher, or 4.2 or higher, and / or 7.0 or lower, 6.5 or lower, 6.0 or lower, or 5.5 or lower. When the Mw / Mn is within the above range, it may be advantageous from the viewpoint of the fluidity of the curable resin composition.

[0041] The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of a polymer can be calculated using gel permeation chromatography (GPC). For example, a vinyl polymer (A) can be analyzed using gel permeation chromatography (GPC), and its weight-average molecular weight or number-average molecular weight can be calculated on a polystyrene basis.

[0042] The viscosity of the vinyl polymer (A) in the curable resin composition according to the present invention is not particularly limited. The viscosity (Pa·s) of the curable resin composition according to the present invention can be measured by an E-type viscometer at a temperature of 20°C.

[0043] (Mw / Hydroxyl value) As described above, vinyl polymer (A) is a polymer obtained by silylation of the multiple hydroxyl groups of vinyl polymer (a), which has multiple hydroxyl groups and a weight-average molecular weight (Mw) / hydroxyl value (unit: mg KOH / g) of more than 4,000. The Mw / hydroxyl value of the hydroxyl group-containing vinyl polymer may be 4,200 or more, or more preferably 4,500 or more. The Mw / hydroxyl value is preferably 5,000 or more, more preferably 6,000 or more, even more preferably 7,000 or more, and particularly preferably 8,000 or more. The upper limit of the Mw / hydroxyl value may be 20,000 or less, 15,000 or less, 12,000 or less, or even more preferably 10,000 or less.

[0044] While there is no intention to limit the theory, it is believed that when the Mw / hydroxyl value is within the above range, the molecular weight between crosslinking points is limited to a specific range, thereby improving the physical properties of the cured resin composition, such as elongation.

[0045] <Vinyl polymer having multiple hydroxyl groups (a)> "Vinyl polymer (a) having multiple hydroxyl groups" has a main chain having repeating units derived from a polymerizable vinyl monomer, and multiple hydroxyl groups (OH groups) bonded to the main chain. For "polymerizable vinyl monomer" and "main chain having repeating units derived from polymerizable vinyl monomer," refer to the above description of vinyl polymer (A). Each of the multiple hydroxyl groups may be independently bonded directly to the carbon atoms constituting the main chain or via a linking group. The linking group may be an alkylene group or a -COOR group. A It may also be the case. Alkylene group and R A Each of these may independently be an alkylene group having 1 to 20 carbon atoms, 1 to 10 carbon atoms, 1 to 5 carbon atoms, or even 2 to 4 carbon atoms.

[0046] The vinyl polymer (a) having multiple hydroxyl groups may be, for example, a polyacrylic polyol.

[0047] (Polyacrylic polyol) The polyacrylic polyol may be a polymer of a (meth)acrylate having a hydroxyl group.

[0048] The method for providing polyacrylic polyols is not particularly limited. Monomers that can be used in synthesizing polyacrylic polyols may be, for example, a combination of a hydroxyalkyl (meth)acrylate for introducing hydroxyl groups and a (meth)acrylic acid ester.

[0049] The alkyl portion of the hydroxyalkyl(meth)acrylate is not particularly limited, but it is preferably a linear, branched, or cyclic alkyl group having 1 to 18 (particularly 1 to 12) carbon atoms. The hydroxyalkyl(meth)acrylate may be, for example, 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, or 4-hydroxybutyl(meth)acrylate. These may be used individually or in combination of two or more.

[0050] The alkyl portion of the alkyl ester of (meth)acrylic acid ester is not particularly limited, but it is preferably a linear, branched, or cyclic alkyl group having 1 to 18 (particularly 1 to 12) carbon atoms. Examples of alkyl esters of (meth)acrylic acid include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, and tridecyl (meth)acrylate. These may be tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, 2-methylpropyl (meth)acrylate, 1,1-dimethylethyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 3-methylbutyl (meth)acrylate, 8-methylnonyl (meth)acrylate, or cyclohexyl (meth)acrylate. These may be used individually or in combination of two or more.

[0051] Polyacrylic polyols may be copolymers obtained by copolymerizing a (meth)acrylate having a hydroxyl group with another (meth)acrylate.

[0052] Other (meth)acrylates may have a carboxyl group and a (meth)acryloyloxy group in their molecule. For example, (meth)acrylic acid, 2-carboxyethyl (meth)acrylate, 4-carboxybutyl (meth)acrylate, etc.

[0053] Furthermore, other (meth)acrylates may have a glycidyl group and a (meth)acryloyloxy group in one molecule. For example, glycidyl (meth)acrylate, 2-epoxyethyl (meth)acrylate, 4-epoxybutyl (meth)acrylate, etc.

[0054] Furthermore, other (meth)acrylates may have both a phenyl group and a vinyl group in one molecule. For example, styrene, vinyltoluene (which may be ortho, meta, or para), etc.

[0055] The form of the vinyl polymer (a) (e.g., polyacrylic polyol) having multiple hydroxyl groups can be selected in various ways. For example, it may be a form in which OH groups are located at both ends of the polymer, a form in which OH groups are located at random positions on the main chain of the polymer, or a form in which OH groups are located at one end of the polymer and at random positions on the main chain of the polymer.

[0056] The weight-average molecular weight Mw of vinyl polymer (a) having multiple hydroxyl groups may be 9,000 or more, 10,000 or more, 12,000 or more, 15,000 or more, 20,000 or more, or 25,000 or more, and / or 65,000 or less, 60,000 or less, 55,000 or less, 50,000 or less, or 45,000 or less. The weight-average molecular weight of vinyl polymer (A) may be, for example, 9,000 to 65,000, or even 15,000 to 45,000. The weight-average molecular weight of vinyl polymer having multiple hydroxyl groups may be, for example, 10,000 to 60,000, or even 15,000 to 50,000.

[0057] The hydroxyl value (mg KOH / g) of the vinyl polymer (a) having multiple hydroxyl groups may be 2.0 or higher, or more specifically, 3.0 or higher. In particular, the hydroxyl value of the vinyl polymer having multiple hydroxyl groups may be 4.0 or higher, 4.4 or higher, or 4.6 or higher, and / or 8.0 or lower, 7.5 or lower, or 7.0 or lower. The hydroxyl value of the vinyl polymer having multiple hydroxyl groups may be, for example, 3.0 to 8.0, or more specifically, 4.0 to 7.0.

[0058] The Mw / Mn of the vinyl polymer (a) having multiple hydroxyl groups may be 1.5 or more, or more specifically 2.0 or more, and preferably 4.0 or more. Preferably, the Mw / Mn of the vinyl polymer having multiple hydroxyl groups may be 4.2 or more, 4.4 or more, 4.6 or more, or 4.8 or more, and / or 7.5 or less, 7.0 or less, 6.5 or less, or 6.0 or less. When the Mw / Mn is within the above range, it may be advantageous from the viewpoint of the fluidity of the curable resin composition.

[0059] The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of vinyl polymer (a) having multiple hydroxyl groups can be calculated using gel permeation chromatography (GPC). For example, vinyl polymer (A) can be analyzed using gel permeation chromatography (GPC), and its weight-average molecular weight or number-average molecular weight can be calculated in polystyrene equivalents. The hydroxyl value (unit: mg KOH / g) of vinyl polymer having multiple hydroxyl groups can be determined by neutralization titration.

[0060] <Silylation of vinyl polymer (a)> The vinyl polymer (a) may be silylated using a compound that can introduce a reactive silyl group to the vinyl polymer (a) having multiple hydroxyl groups via a reaction between the hydroxyl groups and isocyanate groups. The compound may be a single compound or a combination of two or more compounds. If the compound is a combination of two or more compounds, at least one of the compounds has an isocyanate group. The compound that silylates the vinyl polymer (a) may be, for example, an isocyanate silane compound, or a combination of a diisocyanate compound and an aminosilane compound.

[0061] (Isocyanate silane compounds) The isocyanate silane compound may be an isocyanate having a reactive silyl group. For details regarding the "reactive silyl group" contained in the isocyanate silane compound, please refer to the above description concerning vinyl polymer (A).

[0062] The isocyanate silane compound may specifically be, for example, 3-isocyanatetopropyltrimethoxysilane, 3-isocyanatetopropylmethyldimethoxysilane, 3-isocyanatetopropyltriethoxysilane, or 3-isocyanatetopropylmethyldiethoxysilane. From the viewpoint of superior adhesive durability and excellent initial adhesion, 3-isocyanatetopropyldimethoxysilane is preferred, and 3-isocyanatetopropyltrimethoxysilane is preferred.

[0063] The isocyanate silane compound preferably has one isocyanate group per molecule.

[0064] The isocyanate silane compound may also be a compound represented by the following formula (II).

[0065] [ka]

[0066] In formula (II), R 1 , R 2 Each of these independently represents a monovalent hydrocarbon group. The monovalent hydrocarbon group may be, for example, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination thereof. The aliphatic hydrocarbon group may be linear, branched, or alicyclic, or a combination thereof. Among these, an aliphatic hydrocarbon group is preferred. The aliphatic hydrocarbon group may be, for example, a methyl group or an ethyl group. A portion of the compound may undergo hydrolysis to form a silanol group.

[0067] R 3 represents a divalent linking group. The divalent linking group may be a hydrocarbon group. The hydrocarbon group may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination thereof. The aliphatic hydrocarbon group may be linear, branched, or alicyclic, or a combination thereof. From the viewpoint of superior adhesive durability and excellent initial adhesion, an aliphatic hydrocarbon group is preferred, and a linear or branched aliphatic hydrocarbon group is more preferred. From the viewpoint of superior adhesive durability, a trimethylene group or a propylene group is particularly preferred, and a trimethylene group is more preferred. From the viewpoint of superior adhesive durability and excellent initial adhesion, the number of carbon atoms in the linking group (especially an aliphatic hydrocarbon group) is preferably 1 to 6, and more preferably 2 to 3. It is preferable that the linking group is formed from only carbon and hydrogen.

[0068] m is 1 to 3, preferably 2 to 3.

[0069] The isocyanate silane compound may also be a compound having the following chemical formula (III).

[0070] [ka]

[0071] (Combination of diisocyanate compound and aminosilane compound) As described above, vinyl polymer (a) may be silylated by a combination of a diisocyanate compound and an aminosilane compound. For example, the hydroxyl groups of vinyl polymer (a) having multiple hydroxyl groups can be isocyanated with a diisocyanate compound, and then alkoxysilylated with an aminosilane compound or the like. More specifically, for example, reactive silyl groups can be introduced by reacting the hydroxyl groups with a diisocyanate compound and then further reacting with a silane coupling agent such as an aminoalkoxysilane or mercaptoalkoxysilane.

[0072] Diisocyanate compounds include, for example, toluene diisocyanates such as 2,4-toluene diisocyanate and 2,6-toluene diisocyanate, diphenylmethane diisocyanates such as 4,4′-diphenylmethane diisocyanate, 2,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate, 1,2-phenylenediisocyanate, 1,3-phenylenediisocyanate, 1,4-phenylenediisocyanate, and 2,4,6-trimethylphenyl-1,3-diisocyanate. Examples include phenylenediisocyanates such as nate, 2,4,6-triisopropylphenyl-1,3-diisocyanate, naphthalenediisocyanates such as 1,4-naphthalenediisocyanate and 1,5-naphthalenediisocyanate, and aromatic diisocyanates such as chlorophenylene-2,4-diisocyanate, 4,4′-diphenyl ether diisocyanate, 3,3′-dimethyldiphenylmethane-4,4′-diisocyanate, and 3,3′-dimethoxydiphenyl-4,4′-diisocyanate. Other examples include aliphatic diisocyanates such as 1,6-hexamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, decamethylene diisocyanate, and lysine diisocyanate; aromatic aliphatic diisocyanates such as o-xylylene diisocyanate, m-xylylene diisocyanate, and p-xylylene diisocyanate; and alicyclic diisocyanates such as 1,4-cyclohexyl diisocyanate, isophorone diisocyanate, hydrogenated toluene diisocyanate, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Furthermore, polymeric isocyanates such as polymethylene polyphenyl diisocyanate and crude toluene diisocyanate may also be used. Furthermore, these diisocyanates may be modified to obtain modified isocyanates having one or more uretdione bonds, isocyanurate bonds, allophanate bonds, biuret bonds, uretonimine bonds, carbodiimide bonds, urethane bonds, or urea bonds.Preferably, the diisocyanate compound is selected from diphenylmethane diisocyanate (MDI), toluene diisocyanate (TDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), xylene diisocyanate (XDI), and norbornane diisocyanate (NBDI). These may be used individually or in combination of two or more.

[0073] The aminosilane compound may be a silane coupling agent such as aminoalkoxysilane or mercaptoalkoxysilane.

[0074] (Method for manufacturing vinyl polymer (A)) Vinyl polymer (A) can be obtained by a method that includes silylation of the multiple hydroxyl groups of vinyl polymer (a), which has multiple hydroxyl groups and a weight-average molecular weight / hydroxyl value of more than 4,000. For details on the silylation of vinyl polymer (a) having multiple hydroxyl groups, please refer to the above description.

[0075] More specifically, for example, a vinyl polymer (A) can be synthesized by reacting a polyacrylic polyol with an isocyanate silane compound (e.g., an alkoxysilane having an isocyanate group) under heating in the presence of a catalyst (e.g., a Bi catalyst). This reaction will produce a vinyl polymer (A) having a main chain with repeating units of polymerizable vinyl monomers and reactive silyl groups bonded to the main chain via a urethane structure.

[0076] The reaction temperature in the silylation reaction of a vinyl polymer (a) having multiple hydroxyl groups may be, for example, 70°C to 120°C, or even 80°C to 100°C.

[0077] The NCO / OH index in the silylation reaction of vinyl polymer (a) having multiple hydroxyl groups may be 0.8 to 1.2, preferably 0.9 to 1.1, and more preferably 0.95 to 1.05.

[0078] <Other ingredients> The curable resin composition according to the present invention may contain other components besides vinyl polymer (A). These other components may include, for example, a curable resin other than vinyl polymer A, a curing catalyst (e.g., tin catalyst), a filler (e.g., calcium carbonate, carbon black, silica), a plasticizer, a hollow resin, titanium dioxide, a viscosity reducer (e.g., a solvent), a silane coupling agent, an adhesion promoter, a sagging inhibitor, an anti-aging agent (e.g., an ultraviolet absorber, an antioxidant, a light stabilizer), or a pigment. The curable resin composition according to the present invention may contain at least one of these other components.

[0079] (Curable resins other than vinyl polymer A) The curable resin other than vinyl polymer A is not particularly limited, but may be at least one selected from, for example, modified silicone polymer and epoxy resin. From the viewpoint of superior weather resistance, curability, and handling properties, the content of the curable resin other than vinyl polymer A is preferably 0 to 300 parts by mass, and more preferably 0 to 50 parts by mass, per 100 parts by mass of vinyl polymer (A).

[0080] (curing catalyst) The curing catalyst is not particularly limited, but may be any catalyst capable of acting on reactive silyl groups. The curing catalyst may be, for example, a conventionally known catalyst commonly used as a catalyst for hydrolysis and / or condensation of hydrolyzable silyl groups, or as a silanol condensation catalyst. For example, it may be a tin compound, a titanium compound, an acidic compound, or an amine compound. Among these, a tin compound (tin catalyst) is preferred from the viewpoint of excellent curing speed and / or storage stability. The tin compounds may include, for example, tetravalent dialkyltin compounds (e.g., dimethyltin compounds, dibutyltin compounds, dioctyltin compounds), reaction products of dibutyltin oxide and phthalate esters, dialkyltin alcoholates such as dialkylstanoxane dicarboxylate and dibutyltin dimethoxide, (dialkylstanoxane) disilicate compounds, and dialkyltin chelates such as dibutyltin diacetylacetonate; tetravalent monoalkyltin compounds such as monobutyltin trisoctoate, monobutyltin triisopropoxide, and monooctyltin compounds; and divalent tin compounds such as tin octoate, tin naphthenate, and tin stearate.

[0081] From the viewpoint of superior weather resistance, curability, and handling properties, the content of the curing catalyst is preferably 0.1 to 20 parts by mass, and more preferably 0.1 to 5.0 parts by mass, per 100 parts by mass of vinyl polymer (A).

[0082] (Filler) Fillers include, for example, calcium carbonate, organic fatty acid treated calcium carbonate, heavy calcium carbonate, colloidal calcium carbonate; carbon black, graphite; fumed silica, precipitated silica, crystalline silica, fused silica; dolomite; anhydrous silicic acid, hydrated silicic acid; talc, mica, kaolin, zeolite; diatomaceous earth, white clay, clay, calcined clay, talc, slate powder, anhydrous silicic acid, quartz powder; magnesium carbonate; alumina; calcium oxide; magnesium oxide; titanium oxide; bentonite, organic bentonite The fillers may include: ferric oxide; aluminum powder; flint powder; zinc oxide, zinc powder, activated zinc oxide; resin powder, e.g., fine powder of thermoplastic or thermosetting resin, PVC powder, PMMA powder; fibrous fillers, e.g., glass fibers and filaments, carbon fibers; inorganic balloon-like fillers, e.g., glass balloons, shirasu balloons, silica balloons, ceramic balloons; wood powder, walnut shell powder, rice husk powder, pulp powder, cotton chips, rubber powder; and flame retardant fillers, e.g., magnesium hydroxide, aluminum hydroxide. The fillers are preferably calcium carbonate, carbon black, and silica.

[0083] The filler content is preferably 10 to 300 parts by mass per 100 parts by mass of vinyl polymer (A).

[0084] (Plasticizer) The plasticizer may be, for example, phthalate esters such as dioctyl phthalate, diisononyl phthalate (DINP), dibutyl phthalate, or butyl benzyl phthalate; or aliphatic carboxylic acid esters such as dioctyl adipate, diisodecyl succinate, dibutyl sebacate, or butyl oleate. Alternatively, the plasticizer may be, for example, an acrylic plasticizer. The acrylic plasticizer may be, for example, a polymer having a (meth)acrylic skeleton as its main chain skeleton. Alternatively, the plasticizer may be, for example, a polyoxyalkylene polyol such as polyethylene glycol or polypropylene glycol, or a compound obtained by urethaneizing, etherifying, or esterifying a polyoxyalkylene monool, or a high molecular weight plasticizer with a number average molecular weight of 1,000 or more that does not react with the isocyanate group, for example, polystyrenes such as poly-α-methylstyrene; oxyalkylene polymers, or polyoxyalkylene polyols such as polyethylene glycol or polypropylene glycol.

[0085] From the viewpoint of superior weather resistance, curability, and handling properties, the plasticizer content is preferably 1 to 100 parts by mass, and more preferably 10 to 80 parts by mass, per 100 parts by mass of vinyl polymer (A).

[0086] (Hollow resin body) A resin hollow body (resin balloon) has an outer shell made of resin and a hollow interior. Resin hollow bodies can function as fillers. The material of the outer shell of a resin hollow body may be, for example, phenolic resin; urea resin; polystyrene resin; polyvinylidene chloride; acrylonitrile copolymer (e.g., copolymer of acrylonitrile and methacrylonitrile, copolymer of acrylonitrile and vinyl monomers such as butadiene and styrene copolymerizable with acrylonitrile, etc.), thermoplastic resin such as vinylidene chloride polymer, etc. From the viewpoint of superior weather resistance and / or handling properties, acrylonitrile copolymer is preferred as the material of the outer shell of a resin hollow body. The average particle size of a resin hollow body can be 20 μm or more, and is preferably 20 to 70 μm. The average particle size of a resin hollow body can be measured by laser diffraction. From the viewpoint of superior handling properties, the true specific gravity of a resin hollow body is preferably 0.05 to 0.35. The resin hollow body may expand upon heating. The temperature at which the resin hollow body can begin to expand (heat resistance temperature) can be, for example, 100 to 190°C. The resin hollow body may be coated with a filler such as calcium carbonate, talc, or titanium dioxide. From the viewpoint of superior weather resistance and / or handling, it is preferable that the resin hollow body is coated with a filler. The method for manufacturing the resin hollow body is not particularly limited and can be manufactured by conventionally known methods. A commercially available resin hollow body may be, for example, MFL-60CAS manufactured by Matsumoto Oil & Fat Pharmaceutical Co., Ltd.

[0087] From the viewpoint of superior handling properties, the content of the resin hollow body is preferably 1 to 30 parts by mass, more preferably 1 to 10 parts by mass, and even more preferably 1 to 5 parts by mass, per 100 parts by mass of vinyl polymer (A).

[0088] (Anti-aging agent)

[0089] The anti-aging agent may be, for example, an antioxidant, an ultraviolet absorber, or a light stabilizer, or a combination thereof. In one preferred embodiment, it may be a combination of a phenolic or hindered phenolic antioxidant, a hindered amine light stabilizer, and a benzotriazole ultraviolet absorber. In another preferred embodiment, it may be a hindered amine light stabilizer, a hindered phenolic antioxidant, or a mixture thereof.

[0090] From the viewpoint of being excellent in preventing cracks on the surface of the sealing material, the content of the anti-aging agent is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, even more preferably 0.1 to 10 parts by mass, and particularly preferably 0.1 to 5 parts by mass, per 100 parts by mass of vinyl polymer (A).

[0091] (Antioxidant) Using an antioxidant can improve the heat resistance of the cured product. The antioxidant is not particularly limited and may be, for example, a hindered phenol, monophenol, bisphenol, or polyphenol antioxidant, with hindered phenol antioxidants being preferred.

[0092] Examples of hindered phenol antioxidants include pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, N,N'-hexane-1,6-diyrbis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propioamide], 3,5-bis(1,-dimethylethyl)-4-hydroxyC7-C9 side-chain alkyl ester of benzenepropanoate, and 2,4-dimethyl-6-(1-methylpentadecyl)phenol.

[0093] The antioxidant may be butylhydroxytoluene (BHT), butylhydroxytolueneanisole (BHA), benzotriazole, 2-(5-chloro-2H-benzotriazole-2-yl)-4-methyl-6-tert-butylphenol, etc.

[0094] Specific examples of antioxidants are also described in Japanese Patent Publication No. 4-283259 and Japanese Patent Publication No. 9-194731.

[0095] The antioxidant is preferably used in an amount of 0.1 to 10 parts by weight, and more preferably 0.2 to 5 parts by weight, per 100 parts by weight of vinyl polymer (A).

[0096] (Light stabilizer) Using a light stabilizer can prevent photo-oxidative degradation of the cured product. The light stabilizer may be a benzotriazole, hindered amine, or benzoate compound, with hindered amine compounds being preferred.

[0097] Examples of hindered amine-based light stabilizers include bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(2,2,6,6-tetramethyl-1(octyloxy)-4-piperidyl) decandioate ester, bis(1,2,2,6,6-pentamethyl-4-piperidyl)[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]butylmalonate, and methyl 1,2,2,6 ,6-pentamethyl-4-piperidyl sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1-[2-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]ethyl]-4-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]-2,2,6,6-tetramethylpiperidine, 4-benzoyloxy- Low molecular weight compounds with a molecular weight of less than 1,000, such as 2,2,6,6-tetramethylpiperidine; dimethyl succinate-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly[{6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidyl)imino}hexamethylene Examples include {(2,2,6,6-tetramethyl-4-piperidyl)imino}], N,N'-bis(3-aminopropyl)ethylenediamine-2,4-bis[N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino]-6-chloro-1,3,5-triazine condensate, and high molecular weight compounds with a molecular weight of 1,000 or more, such as ADEKA's ADEKA Stab LA-63P and LA-68LD.

[0098] The hindered amine light stabilizers may also be those indicated as follows: Chinuvin 622LD, Chinuvin 144, CHIMASSORB944LD, CHIMASSORB119FL (all manufactured by Ciba Specialty Chemicals Co., Ltd.); MARKLA-57, MARKLA-62, MARKLA-67, MARKLA-63, MARKLA-68 (all manufactured by Asahi Denka Kogyo Co., Ltd.); Sanol LS-770, Sanol LS-765, Sanol LS-292, Sanol LS-2626, Sanol LS-1114, Sanol LS-744 (all manufactured by Sankyo Co., Ltd.). Examples of tertiary amine-containing hindered amine light stabilizers include Chinuvin 622LD, Chinuvin 144, and Chimassol B119FL (all manufactured by Ciba Specialty Chemicals Co., Ltd.); MARK LA-57, LA-62, LA-67, and LA-63 (all manufactured by Asahi Denka Kogyo Co., Ltd.); and Sanol LS-765, LS-292, LS-2626, LS-1114, and LS-744 (all manufactured by Sankyo Co., Ltd.).

[0099] The hindered phenol may also be, for example, 2,4,6-tris-(N-1,4-dimethylpentyl-p-phenylenediamino)-1,3,5-triazine.

[0100] Specific examples of light stabilizers are also shown in Japanese Patent Publication No. 9-194731.

[0101] The light stabilizer is preferably used in an amount of 0.1 to 10 parts by weight, and more preferably 0.2 to 5 parts by weight, per 100 parts by weight of vinyl polymer (A).

[0102] (UV absorber) The curable composition of the present invention may optionally contain an ultraviolet absorber. The use of an ultraviolet absorber can improve the surface weather resistance of the cured product. The ultraviolet absorber is not particularly limited and includes, for example, benzophenone-based, benzotriazole-based, salicylate-based, substituted tolyl-based, and metal chelate compounds, with benzotriazole-based compounds being preferred.

[0103] The benzotriazole-based UV absorber may be, for example, 2-(3,5-di-tert-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole. The triazine-based UV absorber may be, for example, 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[(hexyl)oxy]-phenol. The benzophenone-based UV absorber may be, for example, octabenzone. The benzoate-based UV absorber may be, for example, 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate.

[0104] The ultraviolet absorber is preferably used in an amount of 0.1 to 10 parts by weight, and more preferably 0.2 to 5 parts by weight, per 100 parts by weight of vinyl polymer (A).

[0105] (Silane coupling agent) The curable resin composition of the present invention may further contain a silane coupling agent from the viewpoint of excellent curability, adhesion, or storage stability. The silane coupling agent may be a compound having a hydrolyzable silicon group and other functional groups in its molecule. The hydrolyzable group of the silane coupling agent is not particularly limited and includes known hydrolyzable groups such as hydrogen atoms, halogen atoms, alkoxy groups, acyloxy groups, ketoximate groups, amino groups, amide groups, acid amide groups, aminooxy groups, mercapto groups, and alkenyloxy groups. Among these, hydrogen atoms, alkoxy groups, acyloxy groups, ketoximate groups, amino groups, amide groups, aminooxy groups, mercapto groups, and alkenyloxy groups are preferred, and alkoxy groups are more preferred because they are mildly hydrolyzable and easy to handle. Functional groups other than the hydrolyzable silicon group may be, for example, substituted or unsubstituted amino groups, mercapto groups, epoxy groups, carboxyl groups, vinyl groups, isocyanate groups, isocyanurates, halogens, etc. Among these, substituted or unsubstituted amino groups, epoxy groups, isocyanate groups, and isocyanurates are preferred due to their high adhesion-improving effect, with amino groups being particularly preferred.

[0106] The silane coupling agent may contain an alkoxysilyl group, and may be, for example, vinyltrimethoxysilane, vinylmethyldimethoxysilane, 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane, 3-glycidoxypropyltrimethoxysilane, or 3-glycidoxypropylmethyldiethoxysilane.

[0107] The silane coupling agent may be a ketimine-type silane, such as isocyanate silanes including γ-isocyanatetopropyltrimethoxysilane, γ-isocyanatetopropyltriethoxysilane, γ-isocyanatetopropylmethyldiethoxysilane, γ-isocyanatetopropylmethyldimethoxysilane, (isocyanatetomethyl)trimethoxysilane, and (isocyanatetomethyl)dimethoxymethylsilane; or N-(1,3-dimethylbutylidene)-3-(triethoxysilyl)-1-propanamine.

[0108] The silane coupling agent may be a mercaptosilane, for example, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, or mercaptomethyltriethoxysilane.

[0109] The silane coupling agent may be epoxysilanes, for example, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, or β-(3,4-epoxycyclohexyl)ethyltriethoxysilane.

[0110] The silane coupling agent may be a carboxysilane, for example, β-carboxyethyltriethoxysilane, β-carboxyethylphenylbis(2-methoxyethoxy)silane, or N-β-(carboxymethyl)aminoethyl-γ-aminopropyltrimethoxysilane.

[0111] The silane coupling agent may be a vinyl-type unsaturated group-containing silane, for example, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane, or γ-acryloyloxypropyltriethoxysilane.

[0112] The silane coupling agent may be a halogen-containing silane, for example, γ-chloropropyltrimethoxysilane.

[0113] The silane coupling agent may be an isocyanurate silane, for example, tris(3-trimethoxysilylpropyl)isocyanurate.

[0114] The above silane coupling agents may be used individually or in combination of two or more. Condensed products obtained by partially condensing the above silanes can also be used. Furthermore, reaction products of the above silane coupling agents can also be used. In addition, derivatives obtained by modifying the above compounds, such as amino-modified silyl polymers, silylated amino polymers, unsaturated aminosilane complexes, phenylamino long-chain alkylsilanes, aminosilylated silicones, and silylated polyesters, can also be used as silane coupling agents.

[0115] From the viewpoint of excellent curability, adhesion, and storage stability, the silane coupling agent is preferably in an amount of 0.1 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass, per 100 parts by mass of vinyl polymer (A).

[0116] (Method for producing curable resin compositions) The method for producing the curable resin composition is not particularly limited. For example, the composition of the present invention can be produced by mixing the vinyl polymer (A) according to the present invention with a curing catalyst. Other components can be used as needed. The timing of adding the curing catalyst or other components is not particularly limited.

[0117] The curable resin composition may be produced by the manufacturing method according to the present invention, which includes the following steps: - A vinyl polymer (A) having a main chain having repeating units derived from a polymerizable vinyl monomer and reactive silyl groups bonded to the main chain via a urethane structure, by silylation of the multiple hydroxyl groups of vinyl polymer (a), which has multiple hydroxyl groups and a weight-average molecular weight / hydroxyl value of more than 4,000. - A step of mixing vinyl polymer (A) with other components.

[0118] Details and preferred ranges of each component of the method (vinyl polymer (a) having multiple hydroxyl groups, silylation of vinyl polymer (a), vinyl polymer (A), reactive silyl group, etc.) can be found in the description above.

[0119] For details regarding the steps for preparing vinyl polymer (A), refer to the above description of the production of vinyl polymer (A).

[0120] The step of mixing the vinyl polymer (A) with other components can be carried out as appropriate using methods known to those skilled in the art. The "other components" may include curing catalysts (e.g., tin catalysts), fillers (e.g., calcium carbonate, carbon black, silica), plasticizers, resin hollow bodies, titanium dioxide, viscosity reducers (e.g., solvents), silane coupling agents, adhesion promoters, anti-sagging agents, anti-aging agents (e.g., UV absorbers, antioxidants, light stabilizers), and pigments. Specific examples and preferred ranges of the "other components" can be found in the above description.

[0121] (Applicable base material) The substrates to which the curable resin composition of the present invention can be applied are not particularly limited. The substrates may be, for example, metals, plastics, rubber, glass, concrete, tiles, stone, etc. The method of applying the composition of the present invention to the substrate is not particularly limited.

[0122] (hardening) The curable resin composition of the present invention may be a moisture-curable resin composition that can be cured when used in the presence of moisture. The moisture is not particularly limited and can be, for example, moisture in the air. The temperature conditions when using or curing the composition of the present invention can be, for example, room temperature.

[0123] (Application) The applications of the curable resin composition of the present invention are not particularly limited, but may include, for example, sealants (e.g., for construction), waterproofing materials, adhesives, and coatings.

[0124] <Sealant> This disclosure includes sealing materials containing the vinyl polymer (A) of the present invention. That is, the curable resin composition of the present invention may be a sealing material. Since the curable resin composition of the present invention contains the vinyl polymer (A) according to the present invention, it can exhibit good weather resistance, as well as good tackiness, mechanical properties, handling properties, storage stability, and curability.

[0125] The sealing material of the present invention may contain, as necessary, catalysts, co-catalysts, dehydrating agents, fillers, anti-sagging agents, pigments, antioxidants, etc., to adjust the curing properties. [Examples]

[0126] The present invention will be described in more detail below with reference to examples, but the scope of the present invention is not limited to the examples.

[0127] <<Evaluation Method>> The physical properties of the examples and comparative examples were evaluated as follows.

[0128] <Potential properties of polymers> (viscosity) The viscosity (Pa·s) of the polymer was measured using an E-type viscometer at 20°C.

[0129] (average molecular weight) The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the polymer were measured by gel permeation chromatography (GPC).

[0130] <Weather resistance> The curable resin composition was cured for 7 days under conditions of 23°C and 50% RH (relative humidity). Subsequently, 5 mm thick samples were prepared from the resulting cured material. Each prepared sample was then measured using a metal halide weathermeter (conditions: 63°C, 50% RH, light energy 75 mW / cm²). 2 A weather resistance test was conducted by showering the samples with water for 120 seconds every two hours. After the weather resistance test, each sample was visually inspected, and the presence or absence of cracks was checked every 100 hours (100h) up to 600 hours. The evaluation criteria were as follows: (++) No clearly visible cracks were observed after more than 500 hours. (+) Clearly visible cracks between 400h and 500h (-) Clearly visible cracks between 200h and 400h (--) Clearly visible cracks between 100h and 200h (---)Cracks clearly visible by 100 h

[0131] <Mechanical properties> (50% modulus) The 50% modulus was evaluated based on the tensile properties of the 50% tensile stress (M 50 ) of the cured product of each obtained curable resin composition. The evaluation of the tensile properties was carried out in accordance with JIS K6251:2010 (Vulcanized rubber and thermoplastic rubber - Method for determining tensile properties). That is, the curable resin composition was cured at 23°C for 7 days and at 30°C for 7 days under the conditions of 23°C and 50% RH (relative humidity). Then, a JIS No. 3 dumbbell-shaped sample (initial sample) with a thickness of 2 mm was punched out from the obtained cured product. Using each prepared initial sample, a tensile test was carried out in accordance with JIS K6251:2010 (Vulcanized rubber and thermoplastic rubber - Method for determining tensile properties) under the conditions of a tensile speed of 500 mm / min and room temperature, and the 50% tensile stress (M 50 ) [N / mm 2 was measured at 23°C.

[0132] (Elongation at break) The curable resin composition was cured at 23°C for 7 days and at 30°C for 7 days under the conditions of 23°C and 50% RH (relative humidity). Then, a JIS No. 3 dumbbell-shaped sample (initial sample) with a thickness of 2 mm was punched out from the obtained cured product. Using each prepared initial sample, a tensile test was carried out in accordance with JIS K6251:2010 (Vulcanized rubber and thermoplastic rubber - Method for determining tensile properties) under the conditions of a tensile speed of 500 mm / min and room temperature, and the initial elongation at break (unit: %) was measured.

[0133] <Workability> "Workability" was evaluated as follows: [Initial viscosity] The viscosity of the curable resin composition after standing at 23°C for 1 day (initial) after kneading was measured at 23°C using a B-type viscometer (manufactured by Toki Sangyo Co., Ltd.) with a No. 7 rotor at rotation speeds of 1 and 10 rpm. [Storage stability] Storage stability was evaluated by the viscosity (Pa·s) of the curable resin composition after kneading and leaving it at 23°C for 1 day (initial state), and after heating and accelerating at 70°C for 1 day. The viscosity of the curable resin composition after kneading, leaving it at 23°C for 1 day (initial state), and heating and accelerating at 70°C for 1 day was measured using a Type B viscometer (manufactured by Toki Sangyo Co., Ltd.) and a No. 7 rotor, under conditions of 23°C at rotation speeds of 1 and 10 rpm. [Thixotropy Index (TI)] After preparing the curable resin composition, it was left at 23°C for 1 day (initial), then heated at 70°C for 1 day to accelerate the process, and then left at 23°C for 1 day. The viscosity was then measured at 23°C under the conditions described above, at rotational speeds of 1 rpm and 10 rpm, and the TI was calculated by applying the obtained viscosity values ​​to the following formula. TI is the ratio of the viscosity value at a rotational speed of 1 rpm to the viscosity value at a rotational speed of 10 rpm, as shown in the formula below. TI = (Viscosity value at 1 rpm) / (Viscosity value at 10 rpm) <Initial workability: Evaluation criteria> "Initial workability" was evaluated as follows: (+++) Thixotropy index is 6.0 or higher (++) Thixotropy index is 5.5 or higher and less than 6.0 (+) Thixotropy index is 5.0 or higher but less than 5.5 (-) Thixotropy index less than 5.0

[0134] <Storage Stability: Evaluation Criteria> "Storage stability" was evaluated as follows: (+++) Thixotropy index is 5.5 or higher (++) Thixotropy index is between 4.0 and 5.5 (+) Thixotropy index is 3.0 or higher but less than 4.0 (-) Thixotropy index less than 3.0

[0135] <Curability> "Hardness" was evaluated as follows: [Tack Free Time] A curable resin composition was cast onto a slate board in a bead shape approximately 20 mm wide x 10 mm high x 100 mm long, and left to stand in an environment of 5°C 40% RH or 23°C 50% RH. A 0.1 mm thick polyethylene film was brought into contact with the surface of the curable composition, and the time until the curable resin composition did not adhere to the polyethylene film was measured. (++) Less than 5 hours (+) More than 5 hours and less than 10 hours (-) Over 10 hours [Deep hardenability] Two 10mm thick polyethylene square backing materials were stacked to create a 20mm thick frame. Using this, a 50mm x 50mm square frame was prepared on a slate board. The curable compositions of Examples 1-4 and Comparative Examples 1-2 were immediately poured into the frame and leveled with a spatula to a thickness of 20mm to prepare the test specimens. After the test specimens were left to stand for a predetermined time (7 days) in an environment of 23°C and 50%RH, the cross-section of the composition was cut with a cutter to reveal it, and the surface-hardened portion was removed and its thickness (mm) was measured.

[0136] <<Examples 1-3 and Comparative Examples 1-5>> In Examples 1-3 and Comparative Examples 2-5, vinyl polymers having reactive silane groups were prepared and their properties evaluated using polyacrylic polyols and isocyanate silane compounds having various average molecular weights and hydroxyl values ​​(OH values, unit: mg KOH / g) as shown in Table 2 below. In Comparative Example 1, a reactive silylated polymer with polypropylene glycol (PPG) as the main chain was prepared and its properties evaluated.

[0137] <Example 1> In Example 1, a vinyl polymer having a reactive silane group was prepared as described below, and its properties were evaluated. (i) The polyacrylic polyols shown in Table 2 were reacted with (3-isocyanatetopropyl)dimethoxymethylsilane to silylate them, thereby obtaining vinyl polymers having a main chain with repeating units of polymerizable vinyl monomers and reactive silyl groups bonded to the main chain via a urethane structure. The synthesis conditions were 90°C, Bi catalyst, and an NCO / OH index of 1.0. (ii) A curable resin composition was prepared using the obtained vinyl polymer. The curable resin composition was prepared according to the formulations shown in Table 1 below: (iii) The obtained compositions were subjected to various property evaluations according to the evaluation methods described above. The results are shown in Table 2.

[0138] [Table 1]

[0139] <Examples 2-3> In Examples 2 and 3, compositions were prepared and their properties evaluated in the same manner as in Example 1, except that a vinyl polymer (A) having the properties described in Table 2 below was prepared.

[0140] <Comparative Example 1> In Comparative Example 1, a reactive silylated polymer having a polypropylene glycol main chain as described in Table 2 below was prepared, and its properties were evaluated in the same manner as in Example 1.

[0141] <Comparative Examples 2-5> In Comparative Examples 2 to 5, compositions were prepared and their properties evaluated in the same manner as in Example 1, except that vinyl polymers having the properties described in Table 2 below were prepared. In Comparative Example 2, polymers having an OH group at one end of the polymer were generated and linked together to form polymers with OH groups at both ends. A polymer was obtained.

[0142] <Reference examples 1~2> As a reference example, Table 2 also shows the results of characterization of a polymer having silyl groups at both ends of the main chain of an acrylic polymer and not containing urethane bonds (Reference Example 1). Furthermore, as a reference example, the results of characterization of a terminally silylated acrylic polymer containing a polymer with silyl groups at the ends of the main chain and side chains and not containing urethane bonds (Reference Example 2) are also shown.

[0143] [Table 2]

[0144] In Table 2, "both ends" indicates a configuration in which the polymer has OH groups at both ends, and "one end + random" indicates a configuration in which the polymer has an OH group at one end, as well as an OH group at a randomly located side chain on the main chain.

[0145] As can be seen in Table 2, the compositions of Examples 1 to 3, which contained a vinyl polymer obtained by silylation of a polyacrylic polyol, a vinyl polymer having a Mw / hydroxyl value of over 4,000 and multiple hydroxyl groups, with an isocyanate silane compound, showed better weather resistance compared to the case where a silylated polymer with polypropylene glycol as the main chain was used (Comparative Example 1), and showed better elongation compared to the case where a polyacrylic polyol having a Mw / hydroxyl value of less than 4,000 was used (Comparative Examples 2 to 5). The curable resin compositions of Examples 1 to 3 also showed good workability, storage stability, and curability.

[0146] Furthermore, as can be seen in Table 2, the elongation of the composition tended to be proportional to the distance between the crosslinking points of the polyacrylic polyol. Specifically, when the average distance between crosslinking points was 4,000 or less, the elongation was low; when it was greater than 4,000 (Example 1), the elongation was significantly improved; and when it was greater than 6,000 (Examples 2-3), the elongation characteristics were further improved.

[0147] Furthermore, as can be seen in Table 2, when a reactive silyl group-containing vinyl polymer has urethane bonds, the molecular weight required to ensure sufficient elongation is reduced compared to when it does not have urethane bonds. For example, to achieve an elongation of approximately 370%, a molecular weight of approximately 46,000 is required for a reactive silyl group-containing vinyl polymer (Example 3), while a molecular weight of approximately 71,000 is required for a terminally silylated acrylic polymer without urethane bonds (Reference Example 2). The viscosity of a reactive silyl group-containing vinyl polymer is approximately proportional to the molecular weight between crosslinking points, with higher molecular weight resulting in higher viscosity.

Claims

1. A curable resin composition containing a vinyl polymer (A), The vinyl polymer (A) has a main chain having repeating units derived from a polymerizable vinyl monomer, and reactive silyl groups bonded to the main chain via a urethane structure. The vinyl polymer (A) has multiple hydroxyl groups and is a polymer obtained by silylation of the multiple hydroxyl groups of vinyl polymer (a), which has a weight-average molecular weight / hydroxyl value greater than 4,000 and 12,000 or less. The vinyl polymer (A) is a curable resin composition whose main component is polymer (A-1), which has the reactive silyl group at at least one terminal of the main chain and the reactive silyl group on side chains located at random positions on the main chain.

2. The curable resin composition according to claim 1, wherein the vinyl polymer (A) has a weight-average molecular weight Mw of 10,000 or more and 46,481 or less.

3. The curable resin composition according to claim 1 or 2, wherein the vinyl polymer (A) has a weight-average molecular weight to number-average molecular weight ratio (Mw / Mn) of 4.0 or more.

4. A method for producing a curable resin composition, The steps include: preparing a vinyl polymer (A) having a main chain having repeating units derived from a polymerizable vinyl monomer and reactive silyl groups bonded to the main chain via a urethane structure by silylation of the multiple hydroxyl groups of a vinyl polymer (a) having multiple hydroxyl groups and a weight-average molecular weight / hydroxyl value greater than 4,000 and less than or equal to 12,000; The step includes mixing the vinyl polymer (A) with other components, The vinyl polymer (A) mainly comprises polymer (A-1) having the reactive silyl group at least one of the ends of the main chain and the reactive silyl group on side chains located at random positions on the main chain. A method for producing a curable resin composition.

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