JP2005126672A - Curable composition, sealing material and adhesive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a curable composition which gives a cured product having good elongation properties and exhibiting good rubber elasticity, a sealing material and an adhesive. <P>SOLUTION: The curable composition comprises an organic polymer (a) bearing a crosslinkable hydrolyzable silyl group and at least one filler (b) selected from among silica, alumina, silicon carbide, zirconia, diamond, boron nitride, aluminum nitride and boron nitride. Preferably, the curable composition further contains a layered silicate. The sealing material comprises the curable composition. The adhesive comprises the curable composition. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a curable composition, a sealing material, and an adhesive that are crosslinked and cured by moisture in an atmosphere, and more specifically, an organic polymer containing a crosslinkable hydrolyzable silyl group. The present invention relates to a curable composition that gives a cured product having good elongation properties and high elasticity, a sealing material and an adhesive using the curable composition.

  Conventionally, various curable compositions mainly comprising a (meth) acrylic polymer having an alkoxysilyl group have been proposed (see, for example, Patent Document 1). These curable compositions are crosslinked by moisture in the atmosphere to give a cured product excellent in durability, weather resistance, transparency, and adhesiveness. Therefore, the said curable composition is used for various uses, such as a sealing material, an adhesive agent, a pressure sensitive adhesive, a coating material, a coating material, a sealant, and a primer.

  When the curable composition is used as a sealing material, the cured product may be required to be rubbery and have sufficient elongation.

  As the curable composition, it is reported that calcium carbonate is used as a filler in a vinyl polymer having an alkoxysilyl group in order to improve tensile properties after curing. For example, a blend of heavy and light calcium carbonate or calcium carbonate subjected to surface treatment is disclosed (for example, see Patent Document 1), and a blend of uniform cubic calcium carbonate is disclosed (for example, Patent Document 2).

JP 57-179210 A JP-A-61-37839

  However, in the conventional curable composition using calcium carbonate as a filler, although the elongation of the cured product is improved, the rubber-like elasticity of the cured product is still insufficient.

  An object of the present invention is to provide a curable composition, a sealing material, and an adhesive that give a cured product having good elongation characteristics of the cured product and further having a good rubber-like elasticity in view of the current state of the prior art described above. It is in.

  In order to achieve the above object, the invention described in claim 1 includes an organic polymer (a) containing a crosslinkable hydrolyzable silyl group, silica, alumina, silicon carbide, zirconia, diamond, boron nitride, aluminum nitride. And a curable composition comprising at least one filler (b) selected from boron nitride.

  Moreover, invention of Claim 2 provides the curable composition of Claim 1 which further contains a layered silicate.

  Moreover, invention of Claim 3 provides the sealing material which consists of a curable composition of Claim 1 or 2.

  Moreover, invention of Claim 4 provides the adhesive agent which consists of a curable composition of Claim 1 or 2.

Details of the present invention will be described below.
The curable composition of the present invention is selected from an organic polymer (a) containing a crosslinkable hydrolyzable silyl group and silica, alumina, silicon carbide, zirconia, diamond, boron nitride, aluminum nitride and boron nitride. And at least one filler (b).

(Organic polymer (a))
The organic polymer used in the present invention has at least one hydrolyzable silyl group that can be crosslinked by forming a siloxane bond. This siloxane bond is, for example, a hydroxyl group or hydrolyzable group bonded to a silicon atom. It is formed by.

  Examples of hydrolyzable groups bonded to silicon atoms include hydrogen, halogen atoms, alkoxy groups, acyl oxide groups, ketoximate groups, amino groups, amide groups, acid amide groups, aminooxy groups, mercapto groups, alkenyl oxide groups, and the like. Is a preferred example.

  Examples of the alkoxy group include a methoxy group, an ethoxy group, a propyloxy group, an isopropyloxy group, a butoxy group, a tert-butoxy group, a phenoxy group, and a benzyloxy group. Examples of the alkoxysilyl group to which the alkoxy group is bonded include, for example, a trialkoxysilyl group such as a trimethoxysilyl group, a triethoxysilyl group, a triisopropoxysilyl group, a triphenoxysilyl group; a dimethoxymethylsilyl group, a diethoxymethylsilyl group And dialkoxysilyl groups such as methoxydimethylsilyl group and ethoxydimethylsilyl group. These may be used alone or in combination of two or more.

  As the hydrolyzable silyl group, an alkoxysilyl group such as a methoxysilyl group or an ethoxysilyl group is preferably used because no harmful by-product is formed after the reaction.

(Vinyl polymer)
The main chain of the organic polymer having at least one hydrolyzable silyl group capable of crosslinking by forming a siloxane bond is not particularly limited. Examples thereof include a polymer, a polyester-based polymer, a polycarbonate-based polymer, a polyolefin-based polymer, and the like, and preferably a vinyl-based polymer and / or a polyether-based polymer. That is, the main chain may have one or both of a vinyl polymer portion and a polyether polymer portion. These may be used alone or in combination of two or more.

  The vinyl polymer part constituting the vinyl polymer may be a polymer obtained by polymerizing a vinyl monomer, such as polyethylene, polypropylene, polyisobutylene, poly (meth) acrylate, polystyrene, Examples thereof include polyvinyl chloride, polyvinylidene chloride, polybutadiene, polyisoprene, polyvinyl acetate, polyvinyl alcohol, polyvinyl acetal, and polyvinyl ether. Moreover, the copolymer which has these vinyl-type polymer parts may be sufficient. Preferably, poly (meth) acrylate having a number average molecular weight of 5,000 to 200,000 and a copolymer thereof having a good balance between cohesive strength and adhesiveness are preferable. Here, (meth) acrylate means methacrylate or acrylate.

  Examples of the monomer for obtaining poly (meth) acrylate and its copolymer include 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, isomyristyl (meth) acrylate, stearyl (meth) acrylate , Isobornyl (meth) acrylate, benzyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, glycidyl (meth) acrylate, tetrahydro Rufuryl (meth) acrylate, hexanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol di (Meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy acrylate, Polyester acrylate, urethane acrylate, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropy (Meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 5-hydroxypentyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 3-hydroxy-3-methylbutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, pentaerythritol tri (meth) acrylate, 2-[(meth) acryloyloxy] ethyl 2-hydroxyethylphthalic acid, 2-[(meth) acryloyloxy] ethyl 2-hydroxypropylphthalic acid,

[Compound 1]
CH2 = CH-C (O) O-CH2CH2O-
[C (O) CH2CH2CH2CH2CH2O] n-H
(N = 1-10)
[Compound 2]
CH2 = C (CH3) -C (O) O-CH2CH2O-
[C (O) CH2CH2CH2CH2CH2O] n-H
(N = 1-10)
[Compound 3]
CH2 = CH-C (O) O- (CH2CH2O) n-H
(N = 1-12)
[Compound 4]
CH2 = C (CH3) -C (O) O- (CH2CH2O) n-H
(N = 1-12)
[Compound 5]
CH2 = CH-C (O) O- [CH2CH (CH3) O] n-H
(N = 1-12)
[Compound 6]
CH2 = C (CH3) -C (O) O- [CH2CH (CH3) O] n-H
(N = 1-12)
[Compound 7]
CH2 = C (CH3) -C (O) O- (CH2CH2O) n-
[CH2CH (CH3) O] m-H
(M, n = 1-12)
[Compound 8]
CH2 = CH-C (O) O- (CH2CH2O) n-
[CH2CH (CH3) O] m-H
(M, n = 1-12)
[Compound 9]
CH2 = C (CH3) -C (O) O- (CH2CH2O) n-
(CH2CH2CH2CH2O) mH
(M, n = 1-12)
[Compound 10]
CH2 = CH-C (O) O- (CH2CH2O) n-
(CH2CH2CH2CH2O) mH
(M, n = 1-12)
[Compound 11]
CH2 = CH-C (O) O- (CH2CH2O) n-CH3
(N = 1-10)
[Compound 12]
CH2 = C (CH3) -C (O) O- (CH2CH2O) n-CH3
(N = 1-30)
[Compound 13]
CH2 = CH-C (O) O- [CH2CH (CH3) O] n-CH3
(N = 1-10)
[Compound 14]
CH2 = C (CH3) -C (O) O- [CH2CH (CH3) O] n-CH3
(N = 1-10)
[Compound 15]
CH2 = C (CH3) -C (O) O- (CH2CH2O) n-
[CH2CH (CH3) O] m-H
(M, n = 1-10)
[Compound 16]
CH2 = CH-C (O) O- (CH2CH2O) n-
[CH2CH (CH3) O] m-H
(M, n = 1-10)
[Compound 17]
CH2 = CH-C (O) O- [CH2CH (CH3) O] n
-C (O) -CH = CH2
(N = 1-20)
[Compound 18]
CH2 = C (CH3) -C (O) O- [CH2CH (CH3) O] n
-C (O) -C (CH3) = CH2
(N = 1-20)
[Compound 19]
CH2 = CH-C (O) O- (CH2CH2O) n-C (O) -CH = CH2
(N = 1-20)
[Compound 20]
CH2 = C (CH3) -C (O) O- (CH2CH2O) n
-C (O) -C (CH3) = CH2
(N = 1-20)
Etc.

  Examples of other vinyl monomers include styrene such as styrene, indene, α-methylstyrene, p-methylstyrene, p-chlorostyrene, p-chloromethylstyrene, p-methoxystyrene, p-tert-butoxystyrene, divinylbenzene, and the like. Derivatives; for example, compounds having vinyl ester groups such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl benzoate, vinyl cinnamate; maleic anhydride, N-vinylpyrrolidone, N-vinylmorpholine, (Meth) acrylonitrile, (meth) acrylamide, N-cyclohexylmaleimide, N-phenylmaleimide, N-laurylmaleimide, N-benzylmaleimide, n-propylvinylether, n-butylvinylether, isobutylvinylether, ter -Butyl vinyl ether, tert-amyl vinyl ether, cyclohexyl vinyl ether, 2-ethylhexyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether, 2-chloroethyl vinyl ether, ethylene glycol butyl vinyl ether, tritylene glycol methyl vinyl ether, benzoic acid (4-vinyloxy) butyl, ethylene Glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, tetraethylene glycol divinyl ether, butane-1,4-diol-divinyl ether, hexane-1,6-diol-divinyl ether, cyclohexane-1,4-dimethanol -Divinyl ether, di (4-vinyloxy) butyl isophthalate, glu Di (4-vinyloxy) butyl tartrate, di (4-vinyloxy) butyl trimethylolpropane trivinyl ether, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, 6-hydroxyhexyl vinyl ether, cyclohexane-1,4-di succinate Mention may be made of compounds having a vinyloxy group such as methanol-monovinyl ether, diethylene glycol monovinyl ether 3-aminopropyl vinyl ether, 2- (N, N-diethylamino) ethyl vinyl ether, urethane vinyl ether, polyester vinyl ether and the like.

  A known method can be used for producing the vinyl polymer. For example, a free radical polymerization method, an anionic polymerization method, a cationic polymerization method, a UV radical polymerization method, a living anion polymerization method, a living cation polymerization method, a living radical polymerization method, etc. can be used, and depending on the polymerizable reaction of the monomer A polymerization method may be appropriately selected.

  As a method for introducing a crosslinkable hydrolyzable silyl group, a method of initiating polymerization using an initiator having a crosslinkable hydrolyzable silyl group, or a chain transfer agent having a crosslinkable hydrolyzable silyl group is used. A method of introducing a silyl group simultaneously with polymerization, such as a method, a method of copolymerizing a monomer having a crosslinkable hydrolyzable silyl group (for example, JP 54-123192 A, JP 57-179210 A). , JP-A-59-78220, JP-A-60-23405) or a method of synthesizing a vinyl polymer having an alkenyl group and then introducing an alkoxysilyl group by hydrosilylation (for example, No. 54-40893 and Japanese Patent Laid-Open No. 11-80571). The production method of the vinyl polymer constituting the present invention can use any of the known production techniques as described above without any problem as long as the vinyl polymer is obtained.

  Examples of the chain transfer agent for introducing a crosslinkable hydrolyzable silyl group include functional groups having high chain transfer such as mercaptomethyltrimethylsilane, 3-mercaptopropyltrimethoxysilane, and 3-mercaptopropyldimethoxymethylsilane. And alkoxysilane having a group.

  Examples of the copolymerizable monomer having a crosslinkable hydrolyzable silyl group include N- (3-acryloyloxy-2-hydroxypropyl) -3-aminopropyltriethoxysilane, 3-acryloyloxypropyldimethylmethoxysilane, 3- Acryloyloxypropylmethyldimethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3-acryloyloxypropylmethylbis (trimethylsiloxy) silane, allyltriethoxysilane, allyltrimethoxysilane, 3-allylaminopropyltrimethoxysilane, 3- Methacryloyloxypropyldimethylmethoxysilane, 3-methacryloyloxypropyldimethylethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, 3-methacryloylio Cypropylmethyldiethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropenyltrimethoxysilane, vinylmethyldiacetoxysilane, vinyltriacetoxysilane, vinyldimethylmethoxysilane, vinyldimethylethoxysilane, vinylmethyldiethoxy Silane, vinyltrimethoxysilane, vinyltriethoxysilane, binletriisopropoxysilane, vinyltriphenoxysilane, vinyldimethylisopentenyloxysilane, vinyldimethyl-2-((2-ethoxyethoxy) ethoxy) silane, vinyltris (1- Methylvinyloxy) silane, vinyltris (2-methoxyethoxy) silane, phenylvinyldiethoxysilane, diphenylvinylethoxysilane, 6- It can be mentioned Li triethoxysilyl-2-norbornene, oct-7-enyl trimethoxy silane, styrylethyltrimethoxysilane, the alkoxysilanes having a polymerizable unsaturated group such as.

  The blending amount of the chain transfer agent or copolymerizable monomer for introducing the hydrolyzable silyl group is preferably 0.01 to 20 parts by weight with respect to 100 parts by weight of the vinyl polymerizable monomer. Preferably, it is 0.1 to 5 parts by weight.

  In the present invention, in order to make yellowing of the cured product difficult to occur, the vinyl polymer is preferably obtained by a radical polymerization method using a peroxide as a polymerization initiator. Examples of the peroxide used as the polymerization initiator include benzoyl peroxide, isobutyryl peroxide, isononanoyl peroxide, decanoyl peroxide, lauroyl peroxide, parachlorobenzoyl peroxide, di (3, 5, Diacyl peroxides such as 5-trimethylhexanoyl) peroxide; diisopropyl purge carbonate, di-sec-butyl purge carbonate, di-2-ethylhexyl purge carbonate, di-1-methylheptyl purge carbonate, di-3-methoxybutyl purge Peroxydicarbonates such as carbonate and dicyclohexyl purge carbonate; tert-butyl perbenzoate, tert-butyl peracetate, tert-butyl per-2- Peroxyesters such as tilhexanoate, tert-butyl perisobutyrate, tert-butyl perpivalate, tert-butyl diperadipate, cumyl perneodecanoate; ketones such as methyl ethyl ketone peroxide and cyclohexanone peroxide Peroxides; dialkyl such as di-tert-butyl peroxide, dicumyl peroxide, tert-butyl cumyl peroxide, 1,1-di (t-hexylperoxy) -3,3,5-trimethylcyclohexane Peroxides; hydroperoxides such as cumene hydroxy peroxide and tert-butyl hydroperoxide.

  As for the said peroxide, only 1 type may be used and multiple types may be used together. Further, the peroxide may be added at once or may be added sequentially over a plurality of times.

As another method of introducing the hydrolyzable silyl group, there is a method of synthesizing a polymer having a functional group and then introducing the hydrolyzable silyl group using the functional group. This method is preferable because it is easy to reliably introduce a hydrolyzable silyl group as represented by the formula (1) to the end of the polymer.
-C (R ¹ ) (R ² ) (X) (1)
(In the formula, R ^1, R ² represents a group bonded to an ethylenically unsaturated group of a vinyl monomer. In addition, X represents chlorine, bromine, or halogen atom iodine,.)

  As a method for introducing the hydrolyzable silyl group, for example, an organic halide or a sulfonyl halide compound is used as an initiator, and the vinyl monomer is polymerized using a transition metal complex as a catalyst. And a method of producing a polymer having a halogen at the terminal and converting the halogen of the formula (1) into a hydrolyzable silyl group. In this case, a polymer having halogen at both ends can be obtained by using an initiator having two halogens that serve as polymerization initiation base points.

  The method for converting the halogen of the above formula (1) into a hydrolyzable silyl group is not particularly limited. For example, a compound having an alkenyl group and a hydrolyzable silyl group, a compound having a silyl group and a stabilized carbanion, etc. A compound having a polymerizable alkenyl group and another alkenyl group, an organometallic compound having an alkenyl group, a carboxylic acid metal salt having an alkenyl group, a compound having an alkenyl group and a stabilized carbanion, and the like. Examples include a method in which a halogen of formula (1) is substituted with an alkenyl group, and then a hydrosilane having a hydrolyzable silyl group is reacted with the alkenyl group.

Further, when producing a polymer having a terminal of formula (1), an organic halide having a hydrolyzable silyl group is used as an initiator, and a halogen is present at one end and a hydrolyzable at the other end. After synthesizing a polymer having a silyl group, a polymer having hydrolyzable silyl groups at both ends may be prepared by reacting with halogen and glycol, diamine, dicarboxylic acid or the like. After synthesizing a polymer having a hydrolyzable silyl group at the other end,
Halogen may be converted to a hydrolyzable silyl group by the above reaction. Alternatively, after synthesizing a polymer having a halogen at one end and a hydrolyzable silyl group at the other end, the halogen is converted to an alkenyl group by the reaction described above, and then further converted to a hydrolyzable silyl group. May be.

  In addition, when producing a polymer having a terminal of formula (1), an organic halide having an alkenyl group is used as an initiator, and a polymer having a halogen at one end and an alkenyl group at the other end And a method of converting the alkenyl group to a hydrolyzable silyl group by the above-described method after the halogen is converted to an alkenyl group.

(Polyether polymer)
Examples of the polyether polymer include those in which the main chain consists essentially of a polyether polymer, and polymers in which the main chain consists of polyether and (meth) acrylate. By blending this polyether polymer, the water resistance of the cured product can be increased. When the vinyl polymer and the polyether polymer are used in combination, the blending ratio is 0.1 to 200 parts by weight of the polyether polymer with respect to 100 parts by weight of the vinyl polymer. It is preferable to add, More preferably, it is 0.5-100 weight part.

  When the blending ratio of the polyether polymer is less than 0.1 parts by weight, the effect of improving water resistance may be reduced, and when it exceeds 200 parts by weight, the weather resistance may be lowered and the effect of improving water resistance may be obtained. It may not be so high.

  The above-mentioned polyether polymer essentially represents a general formula [— (R—O) n—, wherein R represents an alkylene group having 1 to 4 carbon atoms. ] A polymer containing a hydrolyzable silyl group which can be cross-linked at the terminal.

  The polyether polymer is synthesized, for example, by reacting a polyalkylene oxide having an allyl group at the terminal with a hydrosilane compound represented by the following formula (2) in the presence of a group VIII transition metal.

Wherein R ³ is a group selected from a monovalent hydrocarbon group and a halogenated monovalent hydrocarbon group, a is an integer of 0, 1 or 2, X is a halogen atom, an alkoxy group, an acyloxy group and Means an atom or group selected from a ketoximate group.)
Examples of the polyalkylene oxide that is the main chain of the polymer include polyethylene oxide, polypropylene oxide, and polybutylene oxide. Polypropylene oxide is preferable in that the cured product of the room temperature curable composition is excellent in water resistance. preferable.

  If the number average molecular weight of the polyether-based polymer is small, the elongation of the cured product is not sufficient, the followability to the joint surface is lowered, and if it is large, the viscosity before curing is increased and the workability of the blending process is deteriorated. Therefore, the number average molecular weight is preferably 4,000 to 30,000, more preferably 10,000 to 30,000, and the molecular weight distribution is preferably 1.6 or less.

  Examples of the polyether polymer include, for example, trade name “MS polymer” (manufactured by Kaneka Chemical Co., Ltd.), MS polymer S-203, S-303, etc. As a product), Cyril SAT-200, SAT-350, SAT-400, as trade name "Exester" (Asahi Glass Co., Ltd.), Exester ESS-3620, ESS-3430, ESS-2420, ESS-2410, etc. Is commercially available.

(Filler (b))
In the curable composition according to the present invention, at least one filler (b) selected from silica, alumina, silicon carbide, zirconia, diamond, boron nitride, aluminum nitride, and boron nitride is added.

  The particle size of the filler (b) is preferably 0.1 to 100 μm, and more preferably 0.1 to 50 μm. If it is less than 0.1 μm, the improvement in elasticity by the filler (b) may not be expected, and if it exceeds 100 μm, the surface of the cured product may be uneven or may not be sufficiently stretched.

The blending ratio of the filler (b) is preferably 10 to 200 parts by volume, more preferably 50 to 150 parts by volume with respect to 100 parts by volume of the organic polymer (a). If the amount is less than 10 parts by volume, the improvement of elasticity by the filler (b) may not be expected. If the amount exceeds 200 parts by volume, the composition may no longer be fluid.
In addition, the volume in the said volume part is calculated | required by dividing a weight by true specific gravity.

  Since the filler (b) has a high particle hardness and is a hard filler, the curable composition to which the filler is added can give a cured product with excellent elasticity, and can absorb and absorb strain. It can be preferably used for a joint part that needs to be restored when released from the joint, a joint part that receives a history of strain, a joint part that requires impact resistance and creep resistance, and the like.

(Layered silicate)
The layered silicate preferably used in the present invention means a silicate mineral having exchangeable cations between layers. The layered silicate used in the present invention is not particularly limited, and examples thereof include smectite clay minerals such as montmorillonite, saponite, hectorite, beidellite, stevensite, nontronite, vermiculite, halloysite, and swelling mica. It is done. Among these, montmorillonite and swellable mica are preferable. The layered silicate may be a natural product or a synthetic product, and these may be used alone or in combination of two or more.

  As the layered silicate, it is more preferable to use smectites or swelling mica having a large shape anisotropy effect defined by the following formula from the viewpoint of improving the mechanical strength and gas barrier property of the curable composition. In addition, the crystal | crystallization surface (A) and crystal | crystallization end surface (B) of layered silicate are typically shown in FIG.

  Shape anisotropy effect = area of crystal surface (A) / area of crystal end face (B)

  As shown in FIG. 2, the exchangeable cations existing between the layers of the layered silicate are ions such as sodium and calcium on the crystal surface, and these ions have ion exchange properties with a cationic substance. Therefore, various substances having a cationic property can be trapped (intercalated) between the layers of the layered silicate.

  Although it does not specifically limit as a cation exchange capacity | capacitance of the said layered silicate, It is preferable that it is 50-200 milliequivalent / 100g. If it is less than 50 milliequivalents / 100 g, the amount of the cationic surfactant that can be trapped (intercalated) between the crystal layers by ion exchange decreases, so the layers may not be sufficiently nonpolarized. On the other hand, when it exceeds 200 milliequivalents / 100 g, the bonding force between the layers of the layered silicate becomes strong, and it may be difficult to increase the distance between the crystal flakes constituting each layer of the layered silicate.

  The layered silicate is blended in an amount of 0.1 to 100 parts by weight with respect to 100 parts by weight of the organic polymer (a). More preferably, it is 0.5 to 50 parts by weight, and particularly preferably 1 to 10 parts by weight. If it is less than 0.1 part by weight, it is difficult for the effect of improving the weather resistance and flame retardancy of the cured product to be exhibited, and if it exceeds 100 parts by weight, the viscosity of the curable composition is increased and workability and productivity are reduced. There is.

  The layered silicate preferably has an average interlayer distance of (001) plane measured by wide-angle X-ray diffraction measurement method of 3 nm or more and dispersed including those existing in 5 layers or less. When the average interlayer distance is 3 nm or more and the dispersion is 5 layers or less, it is advantageous for the weather resistance and flame retardancy performance of the curable composition.

  In the present specification, the average interlayer distance of the layered silicate is an average interlayer distance when the fine flaky crystal is used as a layer, and is obtained by X-ray diffraction peak and transmission electron microscope photography, that is, wide-angle X It can be calculated by a line diffraction measurement method. The state where the layers are cleaved to 3 nm or more and dispersed including those existing in 5 layers or less means that a part or all of the layered silicate laminate is dispersed, This is because the interaction between layers is weakened.

  Furthermore, when the average interlayer distance of the layered silicate is 6 nm or more, it is particularly advantageous for expressing functions such as flame retardancy, mechanical properties, and heat resistance. If the average interlaminar distance is 6 nm or more, the lamellar silicate crystal flake layers separate into layers, and the interaction of the lamellar silicate weakens so that it can be almost ignored. The dispersion state in progresses in the direction of delamination stabilization. That is, the layered silicate is present in a stabilized state in the curable composition in a state where the layered silicates are separated in a flake form one by one.

  As a dispersion state of the layered silicate, it is preferable that the flaky crystals of the layered silicate are highly dispersed in the organic polymer (a). More specifically, it is preferable that 10% by weight or more of the layered silicate is dispersed in a state where it is present in 5 layers or less, more preferably, 20% by weight or more of the layered silicate is 5 layers or less. It is desirable to exist in a state. Furthermore, if the number of laminated flaky crystals is 5 or less, the effect of the addition of the layered silicate can be obtained satisfactorily, but if it is 3 or less, it is more preferable, and it is dispersed in a single layer. More desirable.

  The layered silicate in the present invention is preferably a layered silicate treated with a quaternary ammonium salt. This is because the dispersibility of the layered silicate in the organic polymer (a) can be improved by treating with a quaternary ammonium salt. Further, quaternary ammonium salts are known to have a catalytic action on the crosslinking reaction of the organic polymer (a), and dispersibility is improved by dispersing in the organic polymer (a) together with the layered silicate. At the same time, the curing rate can be accelerated.

  Examples of the quaternary ammonium salt include lauryl trimethyl ammonium salt, stearyl trimethyl ammonium salt, trioctyl ammonium salt, distearyl dimethyl ammonium salt, di-cured tallow dimethyl ammonium salt, distearyl dibenzyl ammonium salt, and N-polyoxyethylene. -N-lauryl-N, N-dimethylammonium salt and the like can be mentioned, and these quaternary ammonium salts may be used alone or in combination of two or more. Among them, a quaternary alkyl ammonium ion salt having an alkyl chain having 6 or more carbon atoms or a polyoxyalkylene chain is preferable because good dispersibility can be obtained.

  Various stirrers can be used to disperse the layered silicate, but if it is difficult to disperse, it may be easy to obtain a desired dispersion state by dispersing using a high shearing device such as a three roll.

(Ultraviolet absorber and light stabilizer)
The curable composition of the present invention preferably contains various ultraviolet absorbers and light stabilizers in order to improve the weather resistance. This is because the layered silicate acts so as to suppress bleeding out of various ultraviolet absorbers and light stabilizers in combination with the layered silicate, so that these are retained in the cured product for a long period of time.

  Examples of the UV absorber include known UV absorbers such as benzotriazole and benzophenone, and among them, a benzotriazole UV absorber is preferable because of its high UV absorption performance. When blending the ultraviolet absorber, 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight is blended with respect to 100 parts by weight of the organic polymer (a). preferable. If the amount is less than 0.1 parts by weight, the effect of improving weather resistance may be insufficient. If the amount exceeds 20 parts by weight, problems such as a loss of appearance as a sealing material due to coloration occur.

  As the light stabilizer, for example, a hindered amine light stabilizer is used. A hindered amine light stabilizer generally exhibits an excellent effect when used in combination with an ultraviolet absorber. Among the hindered amine light stabilizers (hereinafter referred to as light stabilizers), those having a group having a structure represented by the following chemical formula (3) in the molecule are particularly effective when used in combination with a layered silicate. Examples of such hindered amine light stabilizers include bis (2,2,6,6-tetramethyl-4-piperidine) sebacate and poly [{6- (1,1,3,3, -tetramethylbutyl). Amino-1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidine) imino} hexamethylene {(2,2,6,6-tetramethyl- 4-piperidine) imino}] and the like. These may be used alone or in combination of two or more.

  The weather resistance effect of the combined use of the light stabilizer and the layered silicate is considered to be mainly due to the bleedout prevention effect of the light stabilizer. That is, it is considered that the layered silicate interacts with the light stabilizer in the composition to prevent the light stabilizer from escaping from the system.

  When the light stabilizer is blended, 0.1 to 20 parts by weight, and more preferably 0.5 to 10 parts by weight is blended with respect to 100 parts by weight of the organic polymer (a). . If the amount is less than 0.1 parts by weight, the effect of improving the weather resistance may be insufficient. If the amount exceeds 20 parts by weight, coloring problems may occur and the appearance as a sealing material may be impaired.

(Other additives)
In the curable composition of the present invention, unless the effect is hindered from the object of the present invention, a curing accelerator for the organic polymer (a), a viscosity modifier for adjusting the viscosity characteristics of the composition, a thixotropic agent, tensile properties, etc. Physical property modifiers, extenders, reinforcing agents, plasticizers, colorants, flame retardants, UV absorbers, light stabilizers, antioxidants, anti-sagging agents, anti-aging agents, solvents, fragrances, pigments, dyes, A dehydrating agent or the like may be added.

  As the curing accelerator for the organic polymer (a), for example, an organometallic compound can be used. As an organic metal compound that can be suitably used, an organic metal compound obtained by substituting a metal element such as germanium, tin, lead, boron, aluminum, gallium, indium, titanium, and zirconium with an organic group can be given. For example, dibutyltin dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin phthalate, bis (dibutyltin laurate) oxide, dibutyltin bisacetylacetonate, dibutyltin bis (monoester malate), tin octylate, dibutyl Tin compounds such as tin octoate and dioctyl tin oxide, titanate compounds such as tetra-n-butoxy titanate and tetraisopropoxy titanate, and these may be used alone or in combination of two or more.

  As a viscosity modifier, it selects from the high molecular compound with a compatibility with an organic polymer (a), for example, and is suitably selected from the compound mix | blended. For example, acrylic polymers, methacrylic polymers, polyvinyl alcohol derivatives, polyvinyl acetate, polystyrene derivatives, polyesters, polyethers, polyisobutene, polyolefins, polyalkylene oxides, polyurethanes, polyamides, natural rubber, polybutadiene , Polyisoprene, NBR, SBS, SIS, SEBS, hydrogenated NBR, hydrogenated SBS, hydrogenated SIS, hydrogenated SEBS, and the like. Moreover, these copolymers and functional group modified products can be mentioned, and these may be combined as appropriate.

  The thixotropic agent is appropriately selected from substances whose composition exhibits thixotropic properties. For example, polyvinyl pyrrolidone, hydrophobized calcium carbonate, glass balloons, glass beads and the like can be mentioned. For selection of the thixotropic agent, it is desirable to have a surface having a high affinity for the organic polymer (a).

  Examples of physical property modifiers that improve tensile properties include various silane coupling agents such as vinyltrimethoxysilane, dimethyldimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, and phenyltrimethoxy. Silane, diphenyldimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- ( 2-aminoethyl) -3-aminopropyltriethoxysilane, N, N′-bis- [3- (trimethoxysilyl) propyl] ethylenediamine, N, N′-bis- [3- (triethoxysilyl) propyl] ethylene Amines, N, N′-bis- [3- (trimethoxysilyl) propyl] hexaethylenediamine, N, N′-bis- [3- (triethoxysilyl) propyl] hexaethylenediamine, and the like. Two or more kinds may be used in combination.

  As the extender, those which are added to the composition according to the present invention and do not exhibit thixotropic properties can be suitably used. For example, talc, clay, calcium carbonate, magnesium carbonate, calcium silicate, titanium dioxide, carbon black, etc. These may be used alone or in combination of two or more.

  Examples of the plasticizer include phosphate esters such as tributyl phosphate and tricresyl phosphate, phthalate esters such as dioctyl phthalate, fatty acid-basic acid esters such as glycerol monooleate, and dioctyl adipate. Examples include fatty acid dibasic acid esters and polypropylene glycols, and these may be used alone or in combination of two or more.

(Sealing material and adhesive)
Since the sealing material and the adhesive according to the present invention are configured using the above-described curable composition of the present invention, the cured product exhibits excellent elongation characteristics and excellent rubber elasticity, and further reduces viscosity. The coating workability and filling workability are excellent.

Since the curable composition of this invention consists of the above-mentioned structure, it can give the hardened | cured material which has the favorable elongation characteristic of hardened | cured material and has further favorable rubber-like elasticity. When the layered silicate is further included, the weather resistance of the cured product becomes more excellent.
In addition, since the sealing material and the adhesive of the present invention are configured using the curable composition of the present invention described above, they exhibit a low viscosity that is easy to apply and fill, and the cured product has elongation characteristics. It was possible to provide a cured product having good rubber elasticity.

  Hereinafter, the present invention will be described in more detail with reference to examples. In addition, this invention is not limited to a following example.

(Example 1)
(Preparation of organic polymer (a1))
In a 0.5 L separable flask equipped with a stirrer, a cooler, a thermometer, and a nitrogen gas inlet, 100 g of n-butyl acrylate (manufactured by Nippon Shokubai Co., Ltd.), 3-methacryloyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) , “KBM-503”) 0.5 g, 3-mercaptopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., “KBM-803”) 0.2 g, lauryl mercaptan (manufactured by Wako Pure Chemical Industries, Ltd.) 0.1 g and ethyl acetate 100 g After the dissolved oxygen was removed by bubbling with nitrogen gas for 20 minutes, the inside of the separable flask system was replaced with nitrogen gas and the mixture was stirred until it reached reflux. The temperature rose.

  After refluxing, a solution obtained by diluting 0.024 g of 1,1-di (t-hexylperoxy) -3,3,5-trimethylcyclohexane as a polymerization initiator with 1 g of ethyl acetate was added to the polymerization system. After 1 hour, a solution prepared by diluting 0.036 g of 1,1-di (t-hexylperoxy) -3,3,5-trimethylcyclohexane with 1 g of ethyl acetate was added. Further, after 2, 3 and 4 hours after the start of polymerization, di (3,5,5-trimethylhexanoyl) peroxide 0.048 g, 0.12 g, and 0.36 g diluted with 1 g of ethyl acetate were sequentially added. I put it in. Seven hours after the first polymerization initiator was charged, the polymerization was terminated by cooling to room temperature. An ethyl acetate solution of an alkoxysilyl group-containing acrylate polymer having a number average molecular weight of about 50,000 (molecular weight by gel permeation chromatography, converted to polystyrene) was obtained. The average number of silyl functional groups was 1.5.

(Preparation of curable composition)
To 140 g of the ethyl acetate solution of the alkoxysilyl group-containing acrylate polymer prepared in Reference Example 1 above, 30 g of polypropylene glycol (manufactured by Wako Pure Chemical Industries, Ltd., molecular weight 3000) is added, and the ethyl acetate is removed by an evaporator. Toned composition was obtained. Thereafter, 113 g of boron nitride (average particle size: 5 μm, “SGP” manufactured by Tokuyama Co., Ltd.) and 3 g of a curing accelerator (dibutyltin dilaurate) are added to the viscous composition as a filler (b), and sealed. Mix until uniform with a stirrer. Thereafter, it was degassed under reduced pressure for 10 minutes to obtain a white paste-like curable composition.
The alkoxysilyl group-containing acrylate polymer in the ethyl acetate solution of the alkoxysilyl group-containing acrylate polymer was 70 g, the true specific gravity was 1.0, and the volume was 70 cm ³ . The true specific gravity of the boron nitride was 2.26, and the volume was 50 cm ³ . Therefore, the compounding ratio of the filler (b) was 71 parts by volume with respect to 100 parts by volume of the organic polymer (a).

[Adhesive strength]
The obtained curable composition was applied to the end of a pentite N steel plate (150 mm × 30 mm × 2 mm) so that the coating was 0.3 mm in an area of 25 mm × 25 mm, and a slate (150 mm × 30 mm × 8 mm) was applied. The samples were bonded so that the tensile shear adhesive force could be measured, and cooled to 25 ° C. after 7 days at 50 ° C. and 50% relative humidity. Thereafter, the tensile shear adhesive strength was measured at a test speed of 5 mm / min according to JIS K 6852. The results are shown in Table 1.

[Rubber properties]
The obtained curable composition was coated on a polyethylene plate so as to have a thickness of 2 mm, and cured for 7 days in an atmosphere of 20 ° C. and a relative humidity of 50% to obtain a rubbery sheet. The obtained rubber sheet was subjected to a tensile test in a No. 3 dumbbell shape at a crosshead speed of 500 mm / min in accordance with JIS K 6301 to obtain a breaking elongation (%) and a breaking stress (N / mm ² ). The results are shown in Table 1.

(Composition viscosity)
After the obtained curable composition was degassed under reduced pressure, the viscosity immediately after blending was measured using a B-type rotational viscometer (manufactured by Tokyo Keiki Co., Ltd.) under conditions of a rotation speed of 10 rpm and 25 ° C. Further, this curable composition was cured in an oven at 60 ° C. for 60 days, then cooled to 25 ° C., and the viscosity at 25 ° C. was measured again by the same method. The results are shown in Table 1,

[Coating workability]
A 333 mL sealing material cartridge was filled with the curable composition before curing, a discharge and bead coating test was performed using a caulking gun, and evaluation was performed according to the following criteria. The results are shown in Table 1.
○: Good discharge, good bead shape;
Δ: Dischargeable, bead shape defect;
×: Discharge not possible

(Example 2)
In Example 1, as filler (b), in the same manner as in Example 1 except that 100 g of silica (average particle size 0.3 μm, manufactured by Cyberco, “Siberite M6000”) was added instead of 113 g of boron nitride. A curable composition was prepared and evaluated in the same manner. The results are shown in Table 1. The silica had a true specific gravity of 2.0 and a volume of 50 cm 3. Therefore, the compounding ratio of the filler (b) was 71 parts by volume with respect to 100 parts by volume of the organic polymer (a).

(Example 3)
(Preparation of vinyl polymer (a2))
A 1 L three-necked round bottom flask equipped with a reflux tube was charged with cuprous bromide (6.25 g, 156 mmol), acetonitrile (50 mL), and pentamethyldiethylenetriamine (9.1 mL) and replaced with nitrogen gas. Acrylic acid-n-butyl (447 g, 3.9 mol) and diethyl-2,5-dibromoadipate (15.7 g, 43.6 mmol) were added, and the mixture was heated and stirred at 70 ° C. for 7 hours. The mixture was diluted with ethyl acetate and treated with activated alumina. Volatiles were distilled off under reduced pressure to obtain 350 g of poly (acrylic acid-n-butyl) having a halogen at the terminal. The number average molecular weight of the polymer was 10700 by GPC measurement (polystyrene conversion), and the molecular weight distribution was 1.15.

Next, in a 2 L three-necked round bottom flask equipped with a reflux tube, poly (acrylic acid-n-butyl) having halogen at the terminal obtained as described above (350 g), potassium salt of 4-pentenoic acid ( 22.3 g, 161 mmol) and dimethylacetamide (350 mL) were charged and reacted at 70 ° C. for 4 hours in a nitrogen atmosphere. The mixture was diluted with ethyl acetate and washed with 2% hydrochloric acid, brine. The organic layer was dried over Na ₂ SO ₄ and the polymer was isolated by removing the volatiles under reduced pressure. An equivalent amount of aluminum silicate (manufactured by Kyowa Chemical Co., Ltd .: Kyowaard 700PEL) was added to the polymer and stirred at 100 ° C. for 4 hours to obtain poly (butyl acrylate) having an alkenyl group at the terminal. According to ¹ H-NMR analysis, 1.82 alkenyl groups were introduced per oligomer-1 molecule.

Next, the polymer (150 g), dimethoxymethylhydrosilane (18 mL, 145 mmol), dimethyl orthoformate (2.6 mL, 24.2 mmol), and a platinum catalyst were charged into a 200 mL pressure-resistant glass reaction vessel. However, the amount of platinum catalyst used was 2 × 10 ⁻⁴ equivalent in terms of molar ratio to the alkenyl group of the polymer. The reaction mixture was heated at 100 ° C. for 4 hours. The volatile component of the mixture was distilled off under reduced pressure to obtain poly (acrylic acid-n-butyl) having a silyl group at the terminal. According to ¹ H-NMR analysis, 1.46 silyl groups were introduced per oligomer-1 molecule.

  In Example 1, using the organic polymer (a2) obtained above instead of the organic polymer (a1), a curable composition was prepared in the same manner as in Example, and various evaluations were performed. The results are shown in Table 1.

(Comparative Example 1)
A curable composition was obtained in the same manner as in Example 1 except that 100 g of fatty acid-treated calcium carbonate (manufactured by Calcium Shiraishi, “Biscolite U”) was added as a filler (b) in place of 113 g of boron nitride. .

  About the obtained curable composition, it carried out similarly to Example 1, and evaluated adhesive force, rubber | gum physical property, composition viscosity, and application | coating workability, and these results were shown in Table 1.

  From Table 1, it can be seen that those using the filler (b) have high breaking stress and excellent rubber-like elasticity.

Example 4
In Example 1, when preparing the curable composition, 10 g of layered silicate “Somasifu MPE-100” (swelling fluorinated mica organically treated with polyoxypropylene diethyl quaternary ammonium salt, manufactured by Coop Chemical Co., Ltd.) 770 "(hindered amine light stabilizer, manufactured by Ciba Specialty Chemicals) and 5 g of" Tinubin 327 "(benzotriazole ultraviolet absorber, manufactured by Ciba Specialty Chemicals) were added in the same manner as in Example 1. Thus, a curable composition was obtained.

(Measurement of average interlayer distance of layered silicate)
The average interlayer distance of the layered silicate in the curable composition obtained in Example 3 was measured as follows.

  Using a X-ray diffraction measurement device (RINT1100, manufactured by Rigaku Corporation), 2θ of the diffraction peak obtained by diffraction of the layered surface of the layered silicate is measured, and the (001) surface of the layered silicate using the following black diffraction equation The interval was calculated. The following d was defined as the average interlayer distance, and the average interlayer distance was well dispersed as 3 nm or more.

λ = 2 dsin θ
In the formula, λ (nm) = 0.154, d (nm) is the surface spacing of the layered silicate, and θ (degree) is the diffraction angle.

[Confirmation of dispersion state of layered silicate]
The dispersion state of the layered silicate in the cured product was observed with a transmission electron microscope (TEM “JEM-1200EX II” manufactured by JEOL Ltd.), and was present in 5 layers or less.

(Weather resistance evaluation)
The weather resistance of the curable compositions obtained in Examples 1 and 3 was evaluated by the following method. Each compounded composition was applied to a stainless steel plate of 50 mm × 150 mm (thickness 1 mm) at a thickness of 0.5 mm, allowed to stand for 7 days (168 hours) in an atmosphere of 20 ° C. × 60% RH, and then cured and cured. Under the conditions, light irradiation was performed for 150 hours and 400 hours, and the surface state was visually confirmed. The case where there were no cracks was judged as ◯, and the case where some cracks occurred was judged as Δ. The results are shown in Table 2 below.

Light irradiation condition Test apparatus: Eye super UV tester (SUV-F11 type), manufactured by Iwasaki Electric Co., Ltd. Irradiation intensity: 100 mW / cm 2
Limited wavelength: 295 nm to 450 nm
Black panel temperature: 63 ° C
Irradiation distance: 235mm (between light source and sample)
(Note that the light irradiation evaluation by the eye super UV tester varies depending on the material system and test conditions, so it cannot be said unconditionally. However, it is usually about 10 times as severe as that of the sunshine weatherometer. It is said that)

  From Table 2, it can be seen that those with the addition of layered silicate have better weather resistance.

  According to the present invention, it is possible to provide a curable composition that gives a cured product having excellent elongation characteristics and rubber elasticity. Furthermore, the said curable composition can be used for various uses, such as a sealing material, an adhesive agent, a pressure sensitive adhesive, a coating material, a coating material, a sealant, and a primer.

The schematic diagram for demonstrating the crystal | crystallization surface (A) and crystal | crystallization end surface (B) of the flaky crystal | crystallization of a layered silicate. The schematic diagram for demonstrating the exchangeable cation between the layers of layered silicate.

Claims (4)

  An organic polymer (a) containing a crosslinkable hydrolyzable silyl group and at least one filler (b) selected from silica, alumina, silicon carbide, zirconia, diamond, boron nitride, aluminum nitride and boron nitride The curable composition characterized by including these.   The curable composition according to claim 1, further comprising a layered silicate.   A sealing material comprising the curable composition according to claim 1. An adhesive comprising the curable composition according to claim 1 or 2.

Images