JP2005290268A - Curable composition, sealing material and adhesive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a curable composition whose odor is low and which gives good work environments. <P>SOLUTION: This curable composition comprises (a) a (meth)acrylate-based polymer having cross-linkable silyl groups represented by formula (1): -[Si(R<SP>1</SP>)<SB>2-b</SB>(Y)<SB>b</SB>O]<SB>m</SB>-Si(R<SP>2</SP>)<SB>3-a</SB>(Y)<SB>a</SB>[R<SP>1</SP>and R<SP>2</SP>are each a 1 to 20C alkyl, a 6 to 20C aryl, a 7 to 20C aralkyl, or (R')<SB>3</SB>Si- (R' is a 1 to 20C monovalent hydrocarbon group, provided that three R' groups may be identical or different); Y is OH or a hydrolyzable group; (a) is 0, 1, 2 or 3; (b) is 0, 1 o 2; (m) is an integer of 0 to 19, where (a)+(m)(b)≥1], at the terminals, and (b) a primary or secondary amino group-having compound. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a hydrolyzable silyl group-containing (meth) acrylic acid ester-based polymer that is crosslinked by moisture in the atmosphere and gives a cured product excellent in durability, and a curable composition using the polymer, and more Specifically, the present invention relates to a (meth) acrylic acid ester-based polymer and a curable composition having a small residual monomer odor and excellent work environment characteristics.

  Vinyl polymers having an alkoxysilyl group are disclosed, for example, in Patent Documents 1 to 3 below. The vinyl polymer having an alkoxysilyl group is crosslinked by moisture in the atmosphere to give a cured product excellent in durability, weather resistance, transparency and adhesiveness. Accordingly, the alkoxysilyl group-containing vinyl polymer is used in a wide range of applications such as paints, coating agents, adhesives, pressure-sensitive adhesives, sealants, and sealing materials.

  In order to make the composition containing the alkoxysilyl group-containing vinyl polymer into a liquid composition so that the coating operation is easy and the cured product after curing has rubber elasticity, A (meth) acrylic acid ester polymer is preferably used.

However, in the production of (meth) acrylic acid ester polymer, after polymerization of (meth) acrylic acid ester monomer, (meth) acrylic acid ester monomer remains and all monomers are completely converted to polymer. It was difficult.

  Normally, it is possible to remove the residual (meth) acrylic acid ester monomer having high volatility under reduced pressure and heating, but it is difficult to completely remove the monomer. Moreover, it was difficult to remove the (meth) acrylic acid ester monomer having a high boiling point more completely. If the (meth) acrylic acid ester monomer remains in the curable composition, the odor remains strong and the working environment is significantly impaired. Moreover, irritation | stimulation was sometimes given to skin by contact with skin.

JP 57-179210 A JP-A-4-202585 JP 11-43512 A

  An object of the present invention is to provide a curable composition that has a remarkably low odor due to residual (meth) acrylic acid ester monomer and that can provide a good working environment, and a sealing material and an adhesive using the cured composition. It is to provide.

The curable composition according to the present invention comprises a (meth) acrylic acid ester polymer (a) having a crosslinkable silyl group represented by the formula (1) and a compound having a primary or secondary amino group (b) And a curable composition.
_{^{- [Si (R 1) 2}} -b (Y) b O] m -Si (R 2) 3-a (Y) a (1)
(In the formula, R ¹ and R ² are all alkyl groups having 1 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms, or aralkyl groups having 7 to 20 carbon atoms, or (R ′) ₃ Si— ( R ′ represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, and three R ′ may be the same or different, and represents a triorganosiloxy group represented by R ¹ Alternatively, when two or more R ² are present, they may be the same or different, Y represents a hydroxyl group or a hydrolyzable group, and when two or more Y are present, they are the same. A may be 0 or 1, 2, or 3, and b may be 0, 1, or 2. m is an integer of 0 to 19, provided that a + mb ≧ 1 to be satisfied.)

In a specific aspect of the curable composition according to the present invention, the residual (meth) acrylic acid ester monomer concentration in the composition is 0.5% by weight or less.
In the curable composition which concerns on this invention, Preferably, the boiling point of the said compound (b) which has the primary or secondary amino group is 50 to 200 degreeC at 1 atmosphere.

  In another specific aspect of the curable composition according to the present invention, the compound (b) having the primary or secondary amino group is 0 with respect to 100 parts by weight of the methacrylic ester polymer (a). .1 to 20 parts by weight.

In still another specific aspect of the curable composition according to the present invention, a polyether polymer (c) having a hydrolyzable silyl group is further included.
In still another specific aspect of the curable composition according to the present invention, a layered silicate is further contained.

The sealing material and the adhesive according to the present invention are characterized by comprising the curable composition according to the present invention.
Details of the present invention will be described below.

((Meth) acrylic acid ester polymer (a))
The curable composition of the present invention contains a (meth) acrylic acid ester polymer (a) having the general formula (1) at its terminal.
_{^{- [Si (R 3) 2}} -b (Y) b O] m -Si (R 4) 3-a (Y) a (1)
(In the formula, R ¹ and R ² are all alkyl groups having 1 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms, or aralkyl groups having 7 to 20 carbon atoms, or (R ′) ₃ Si— ( R ′ represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, and three R ′ may be the same or different, and represents a triorganosiloxy group represented by R ¹ Alternatively, when two or more R ² are present, they may be the same or different, Y represents a hydroxyl group or a hydrolyzable group, and when two or more Y are present, they are the same. A may be 0 or 1, 2, or 3, and b may be 0, 1, or 2. m is an integer of 0 to 19, provided that a + mb ≧ 1 to be satisfied.)

  The hydrolyzable group represented by Y is not particularly limited, and examples thereof include an alkoxy group such as hydrogen, a halogen atom, a methoxy group, and an ethoxy group, an acyl oxide group, a ketoximate group, an amino group, an amide group, and an acid amide group. An aminooxy group, a mercapto group, an alkenyl oxide group and the like are preferable examples, and an alkoxy group that is easy to handle and does not generate harmful by-products during the reaction is particularly preferable. The hydroxyl group and hydrolyzable group can be bonded to one silicon atom in the range of 1 to 3, and the total number of hydroxyl groups and hydrolyzable groups in the formula (1), that is, a + mb is 1 to 1 A range of 5 is preferred. When two or more hydrolyzable groups or hydroxyl groups are bonded to the crosslinkable silicon group, they may be the same or different. The number of silicon atoms constituting the crosslinkable silicon compound may be one or two or more. In the case of silicon atoms linked by a siloxane bond, up to about 20 silicon atoms may be used.

  In addition, the number average molecular weight of the (meth) acrylic acid ester polymer (a) is excellent in the balance between cohesive force and adhesiveness and elongation of the cured product, so the number average molecular weight is in the range of 5,000 to 200,000. It is desirable that Note that (meth) acryl is used as an expression including both acrylic and methacrylic.

(Meth) acrylic acid ester polymer (a)
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, tetrahydrofurfuryl (meth) acrylate, hexanediol di (meth) acrylate, ethyl 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-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydride Xylbutyl (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 to 20).

  Moreover, as a monomer used in obtaining the (meth) acrylic acid ester-based polymer according to the present invention, not only the above (meth) acrylic acid ester-based monomer but also the following copolymerizable monomer is used in combination. May be. Examples of such copolymerizable monomers include styrene, indene, α-methylstyrene, p-methylstyrene, p-chlorostyrene, p-chloromethylstyrene, p-methoxystyrene, p-tert-butoxystyrene, divinyl. Styrene derivatives such as benzene; maleic anhydride, N-vinylpyrrolidone, N-vinylmorpholine, (meth) acrylonitrile, (meth) acrylamide, N-cyclohexylmaleimide, N-phenylmaleimide, N-laurylmaleimide, N-benzylmaleimide Compounds having a vinyl ester group such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl benzoate, vinyl cinnamate; n-propyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether , Tert-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 Chill, di (4-vinyloxy) butyl glutarate, di (4-vinyloxy) butyl trimethylolpropane trivinyl ether, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, 6-hydroxyhexyl, vinyl ether, cyclohexane-1 Examples thereof include compounds having a vinyloxy group such as 4-dimethanol-monovinyl ether, diethylene glycol monovinyl ether, 3-aminopropyl vinyl ether, 2- (N, N-diethylamino) ethyl vinyl ether, urethane vinyl ether, and polyester vinyl ether.

  It is preferable that the compounding quantity of the (meth) acrylic acid ester monomer containing an alkoxy silyl group is 0.01-20 weight part with respect to 100 weight part of polymerizable monomers, More preferably, it is 0.1-5 weight Part.

The production method of the (meth) acrylic acid ester polymer having a crosslinkable silyl group of formula (1) at the end is not particularly limited. For example, an organic halide or a sulfonyl halide compound is used as an initiator, transition metal By polymerizing the (meth) acrylate monomer using the complex as a catalyst, a (meth) acrylate polymer having a terminal structure represented by the formula (2) is produced, and the halogen of the formula (2) is represented by the formula ( The method of converting into the crosslinkable silyl group containing substituent shown to 1) is mentioned.
-C (R ³ ) (R ⁴ ) (X) (2)
(In the formula, R ^3, R ⁴ represents a group bonded to an ethylenically unsaturated group of a vinyl monomer. In addition, X represents chlorine, bromine, or halogen atom iodine,.)
It is.

  The method for converting the halogen of the above formula (2) into the crosslinkable silyl group-containing substituent represented by the formula (1) is not particularly limited. For example, a compound having an alkenyl group and a crosslinkable silyl group, a silyl group, A method of reacting a compound having a stabilized carbanion, 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, an alkenyl group and a stabilized carbanion For example, a method in which a halogen compound represented by formula (2) is substituted with an alkenyl group and then a hydrosilane having a crosslinkable silyl group is reacted with the alkenyl group.

  Moreover, when manufacturing the (meth) acrylic acid ester-type polymer which has a crosslinkable silyl group of Formula (1) at the terminal, the organic halide which has a crosslinkable silyl group is used as an initiator, and one end is used. After synthesizing a (meth) acrylic acid ester polymer having a halogen and a crosslinkable silyl group at the other end, the polymer is reacted with halogen, glycol, diamine, dicarboxylic acid or the like to have a crosslinkable silyl group at both ends. A polymer may be prepared, or after synthesizing a polymer having a halogen at one end and a crosslinkable silyl group at the other end, the halogen may be converted to a crosslinkable silyl group by the above reaction. . Alternatively, after synthesizing a polymer having a halogen at one end and a crosslinkable silyl group at the other end, the halogen may be converted to an alkenyl group by the above-described reaction, and then further converted to a crosslinkable silyl group. good.

  In addition, when producing a (meth) acrylic acid ester polymer having a crosslinkable silyl group of formula (1) at the terminal, an organic halide having an alkenyl group is used as an initiator, and halogen is added at one end. Examples thereof include a method in which a polymer having an alkenyl group at the other end is synthesized, a halogen is converted into an alkenyl group, and then the alkenyl group is converted into a crosslinkable silyl group by the above-described method.

(Compound (b) having primary or secondary amino group)
The compound (b) having a primary or secondary amino group used in the present invention is not particularly limited as long as it is a compound containing a primary or secondary amino group having active hydrogen in one molecule. A compound having both a primary amino group and a secondary amino group may be used.

  In the present invention, the compound (b) acts to reduce the (meth) acryloyl group by causing a Michael addition reaction with the residual (meth) acrylic acid ester monomer. Accordingly, the compound (b) is preferably a compound that gives a product having low volatility even after the Michael addition reaction, and a compound having a boiling point of 50 ° C. or more and 200 ° C. or less at 1 atm. Moreover, the compound which has a primary amino group which is easy to cause a Michael addition reaction is preferable. Further, a compound having one amino group in one molecule, which is unlikely to cause aggregation due to hydrogen bonding between the compounds (b), is preferable.

  Examples of the compound having a primary amino group include methylamine, ethylamine, propylamine, butylamine, pentylamine, octylamine, laurylamine, stearylamine, ethylenediamine, hexamethylenediamine, and other alkylamines; cyclohexylamine, 1-adamantanamine, Benzylamine; α, ω-diaminopropylene glycol; α, ω-diaminoethylene glycol; aromatic amines such as aniline, methylaniline, methylenediphenyldiamine; γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane It is done.

  Examples of the compound having a secondary amino group include dimethylamine, diethylamine, dipropylamine, dibutylamine, dipentylamine, dioctylamine, dilaurylamine, distearylamine, diphenylamine, N-methylaniline, and N-ethylaniline. Can be mentioned.

  Examples of the compound having both a primary amino group and a secondary amino group include diethylenetetramine, N- (3-aminoethyl) -1,3-propanediamine, and N- (3-aminopropyl) -1,3-propane. Examples include diamine, N- (3- (trimethoxysilyl) propyl) ethylenediamine, and N- (3- (trimethoxysilyl) propyl) diethyleneditetraamine.

(Curable composition)
The curable composition according to the present invention is obtained by mixing the (meth) acrylic acid ester polymer (a) having a crosslinkable silyl group and the compound (b) having a primary or secondary amino group. can get. In this case, it is preferable to mix | blend with 0.1-20 weight part with respect to 100 weight part of (meth) acrylic acid ester polymer (a), More preferably, it is 0.5-10 weight part, More preferably It mix | blends in the ratio of 1.0-5 weight part. If the compounding ratio of the compound (b) is less than 0.1 parts by weight, the effect of reducing the residual monomer odor may be impaired by the compound (b), and if it exceeds 20 parts by weight, the effect of reducing the residual monomer may be Although it is excellent, the adhesiveness and elongation of the cured product may be impaired by the excessive blending of the compound (b).

(Layered silicate)
In the curable composition concerning this invention, in order to improve a weather resistance, a layered silicate may be mix | blended.

  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 one or more of these may be used.

  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, more preferably 0.5 to 50 parts by weight, and particularly preferably 1 to 10 parts by weight with respect to 100 parts by weight of the base resin. When the amount is less than 0.1 part by weight, the effect of improving the weather resistance of the cured product and flame retardancy is hardly exhibited, and when the amount exceeds 10 parts by weight, the viscosity of the curable composition is increased and workability and productivity are reduced. There is.

  The base resin is the above-mentioned (meth) acrylic acid ester polymer (a), or the above-mentioned (meth) acrylic acid ester polymer (a) and a polyether polymer described later which is added as necessary. Is the sum of

  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 base resin. 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 of 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 base resin 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 (meth) acrylic acid ester polymer (a), and are dispersed by dispersing in the base resin together with the layered silicate. It becomes possible to accelerate the curing rate as well as to improve.

  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 bleed-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 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 the ultraviolet absorber is blended, it is preferably blended in an amount of 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight with respect to 100 parts by weight of the base resin. When the amount is less than 0.1 parts by weight, the effect of improving weather resistance may be insufficient. When the amount exceeds 20 parts by weight, problems such as deterioration of the 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 general formula (A) in the molecule are particularly effective when used in combination with a layered silicate. Examples of such a hindered amine light stabilizer include, for example, bis (2,2,6,6-tetramethyl-4-piperidine) sebacate, 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.

  It is considered that the weather resistance effect by the combined use with the layered silicate is mainly due to the bleed-out 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. In addition, it is considered that the bleedout of the light stabilizer is suppressed when the layered silicate acts like a plate that inhibits bleedout among the interactions. Among the light stabilizers, those having a group having the structure represented by the following general formula (A) in the molecule are considered to be particularly effective because the H atom bonded to the N atom is involved. .

  When the light stabilizer is blended, it is preferably blended in an amount of 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight with respect to 100 parts by weight of the base resin. If the amount is less than 0.1 part 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.

(Polyether polymer (c))
In the curable composition according to the present invention, a polyether polymer (c) having a main chain essentially composed of a polyether polymer and having a crosslinkable hydrolyzable silyl group may be blended. Examples of the polyether polymer (c) 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) acrylic acid ester. By blending this polyether polymer (c), the water resistance of the cured product can be increased, and the rubber elasticity when a sealing material is formed can be increased. When the (meth) acrylic acid ester polymer and the polyether polymer (c) are used in combination, the blending ratio is based on 100 parts by weight of the (meth) acrylic acid ester polymer. The blend (c) is preferably added at a rate of 0.1 to 100 parts by weight, more preferably 0.5 to 100 parts by weight.

  When the blending ratio of the polyether polymer (c) is less than 0.1 parts by weight, the effect of improving the adhesiveness may be reduced, and when it exceeds 200 parts by weight, the weather resistance may be lowered and the adhesiveness may be decreased. The improvement effect may not be so high.

  The polyether polymer (c) 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 polymer (c) is synthesized, for example, by reacting a polyalkylene oxide having an allyl group at the terminal with a hydrosilane compound represented by the following chemical formula (3) in the presence of a group VIII transition metal.

Wherein R 1 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 a ketoximate Means an atom or group selected from the group.)
Examples of the polyalkylene oxide that is the main chain of the polymer include polyethylene oxide, polypropylene oxide, polybutylene oxide, etc., but the cured product of the room temperature curable composition is excellent in water resistance and as a sealing material. Polypropylene oxide is preferable because it can ensure elasticity.

  As the crosslinkable hydrolyzable silyl group, those which do not generate harmful by-products after the reaction are preferable, and examples thereof include alkoxysilyl groups such as methoxysilyl group and ethoxysilyl group.

  When the number average molecular weight of the polyether polymer (c) decreases, the elongation of the cured product becomes insufficient, the followability to the joint surface decreases, and when it increases, the viscosity before curing increases, and the workability of the blending process increases. Becomes worse. 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 (c) include the trade name “MS polymer” (manufactured by Kaneka Chemical Co., Ltd.), MS polymer S-203, S-303, etc. As Sakai Chemical Industry Co., Ltd.), Silyl SAT-200, SAT-350, SAT-400, and trade name "Exester" (manufactured by Asahi Glass Co., Ltd.), Exester ESS-3620, ESS-3430, ESS-2420, ESS -2410 and the like are commercially available.

(Other ingredients)
In the curable composition according to the present invention, a curing catalyst, a curing co-catalyst, a viscosity modifier, a thixotropic agent, a physical property modifier, an extender, a reinforcing agent, a plasticizer, as long as the object and effect of the present invention are not impaired. Colorants, flame retardants, sagging inhibitors, antioxidants, anti-aging agents, solvents, fragrances, pigments, dyes, dehydrating agents, and the like may be added.

  Examples of the curing catalyst include dibutyltin dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin phthalate, bis (dibutyltin laurate) oxide, dibutyltin bisacetylacetonate, dibutyltin bis (monoester maleate), Tin compounds such as tin octylate, dibutyltin octoate and dioctyltin oxide; titanate compounds such as tetra-n-butoxy titanate and tetraisopropoxy titanate; amine salts such as dibutylamine-2-ethylhexoate; and others And acidic catalysts and basic catalysts. Further, in order to adjust the curing rate, divalent organic carboxylate tin having a relatively fast curing rate may be used, and these include tin stearate, stannous octoate, and dioctyl tin compounds. .

  The viscosity modifier is, for example, selected from a polymer compound having a good compatibility with a polymer composed of a repeating unit having a substantially (meth) acrylic acid ester having an alkoxysilyl group as a monomer, and appropriately selected from compounds to be blended Is done. 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. Examples thereof include colloidal silica, polyvinyl pyrrolidone, hydrophobized calcium carbonate, glass balloons, and glass beads. Regarding the selection of the thixotropic agent, it is desirable to have a surface having high affinity with a polymer composed of a repeating unit having a substantially (meth) acrylic acid ester having an alkoxysilyl group as a monomer.

  Examples of physical property modifiers that improve tensile properties include various silane coupling agents such as vinyltrimethoxysilane, dimethyldimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, and phenyltrimethoxysilane. Methoxysilane, 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 ] Echile And diamine, N, N′-bis- [3- (trimethoxysilyl) propyl] hexaethylenediamine, N, N′-bis- [3- (triethoxysilyl) propyl] hexaethylenediamine, and the like. Two or more types may be used in combination.

  As the extender, those which are added to the composition according to the present invention and do not express thixotropic properties can be suitably used. For example, talc, clay, calcium carbonate, magnesium carbonate, anhydrous silicon, hydrous silicon, calcium silicate, Examples thereof include titanium dioxide and carbon black, and 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 thereof include fatty acid dibasic acid esters and polypropylene glycols, and these may be used alone or in combination of two or more.

The curable composition according to the present invention is cured by reacting with moisture in the atmosphere to give a cured product having rubber elasticity.
In the curable composition according to the present invention, in the hydrolyzable silyl group-containing polymer, since the residual (meth) acrylic acid ester concentration is low, an unpleasant monomer odor hardly occurs, and thus the working environment can be improved. .

The curable composition according to the present invention comprises a (meth) acrylic ester polymer (a) having a hydrolyzable silyl group and a compound (b) having a primary or secondary amino group, Since residual monomer is reduced by (b), the monomer odor is remarkably reduced and a curable composition excellent in work environment can be provided. Moreover, the curable composition which concerns on this invention hardens | cures rapidly with the humidity in atmosphere, and gives the hardened | cured material which has elasticity.
In particular, the crosslinkable silyl group-containing vinyl polymer (a) of the present invention has a crosslinkable silyl group at the terminal as described above, so that it has a crosslinkable silyl group in the side chain. The cured product exhibits excellent elongation and elasticity despite its low viscosity before curing and easy handling with little stringing.
Therefore, according to the present invention, it is possible to provide a curable composition that is suitably used for various adhesives, sealing materials, and the like and that is excellent in work environment.

  Hereinafter, the present invention will be described in more detail by describing specific examples of the present invention. The present invention is not limited to the following examples.

(Example 1)
(Preparation of vinyl polymer (a))
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 (500 mL, 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 (polymerization yield: 87%). 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), synthesized in Production Example 2 4 -A potassium salt of 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.

(Example 1)
After mixing 100 g of an ethyl acetate solution of the alkoxysilyl group-containing (meth) acrylic acid ester polymer (a) obtained above and 50 g of polypropylene glycol (manufactured by Wako Pure Chemical Industries, Ltd., average molecular weight 3000), a rotary evaporator. Was used to remove ethyl acetate to obtain a viscous liquid curable composition (about 30,000 cps, 25 ° C.). The residual monomer amount of butyl acrylate at this time was measured by the method described later and found to be 0.8% by weight. 10 g of α, ω-diaminopropylene glycol (manufactured by Texaco Chemical Co., JEFFAMINE D-230) was added to the obtained liquid curable composition, and the mixture was allowed to stand at room temperature for 6 hours. It was 0.1 weight% when measured. To the curable composition left for 6 hours, further add 20 g of fatty acid surface-treated calcium carbonate, 50 g of heavy calcium carbonate, and 3 g of a curing accelerator (dibutyltin dilaurate), and mix until uniform with a sealed stirrer. Thereafter, the mixture was degassed under reduced pressure for 10 minutes to obtain a room temperature curable composition of a white paste. No odor due to residual monomer was felt.

  The obtained curable composition was coated on a polyethylene plate so as to have a film thickness of 2.5 mm, and then cured for 7 days in an environment of 20 ° C. and a relative humidity of 50% to form a rubber-like sheet coating. Obtained. The rubber properties of this sheet coating were evaluated in the following manner. The elongation at break was 550% and the break stress was 0.21 N / mm 2.

(Measurement of residual monomer)
Using Shimadzu Corporation gas chromatography (GC14A), after preparing a calibration curve with a monomer dilution solution whose concentration is known in advance, a sample of unknown concentration is quantitatively diluted with acetone, and the diluted solution is subjected to gas chromatography. The amount of residual monomer was quantified based on the above calibration curve.

(Evaluation of rubber properties)
The above rubber-like sheet coating cured for 7 days in an atmosphere of 20 ° C. and 50% relative humidity is subjected to a tensile test at a crosshead speed of 500 mm / min in a No. 3 dumbbell shape according to JIS K6301, and elongation at break (%) And the breaking stress (N / mm @ 2) were determined.

(Example 2)
After mixing 100 g of an ethyl acetate solution of the (meth) acrylate polymer (a) obtained in Reference Example 1 and 50 g of polypropylene glycol (manufactured by Wako Pure Chemical Industries, Ltd., average molecular weight 3000), a rotary evaporator was used. By removing the solvent, a viscous liquid curable composition was obtained (viscosity was about 30,000 cps, 25 ° C.). The residual monomer amount of butyl acrylate at this time was measured in the same manner as in Example 1 and found to be 0.8% by weight. When 5 g of n-octylamine (manufactured by Wako Pure Chemical Industries, Ltd.) was added to the obtained liquid curable composition and allowed to stand at room temperature for 6 hours, the residual monomer amount of butyl acrylate was measured again. %Met. To the curable composition left for 6 hours, 20 g of fatty acid surface-treated calcium carbonate, 50 g of heavy calcium carbonate, and 3 g of a curing accelerator (dibutyltin dilaurate) are added and mixed with a sealed stirrer until uniform. Defoaming was performed under reduced pressure for 10 minutes to obtain a room temperature curable composition of a white paste. No odor due to residual monomer was felt.

  The obtained curable composition was coated on a polyethylene plate so as to have a film thickness of 2.5 mm, and then cured for 7 days in an environment of 20 ° C. and a relative humidity of 50%. A sheet film was obtained. When the rubber physical properties of this sheet coating were evaluated in the same manner as in Example 1, the elongation at break was 550% and the stress at break was 0.21 N / mm 2.

(Comparative Example 1)
After mixing 100 g of the (meth) acrylic acid ester polymer (a) obtained in Reference Example 1 and 50 g of polypropylene glycol (manufactured by Wako Pure Chemical Industries, Ltd., average molecular weight 3000), ethyl acetate was mixed using a rotary evaporator. Removal of a viscous liquid curable composition was obtained. The viscosity of this viscous liquid curable composition at 25 ° C. was about 30,000 cps. The amount of residual butyl acrylate monomer in the curable composition was 0.8% by weight.

  Furthermore, 20 g of fatty acid surface-treated calcium carbonate, 50 g of heavy calcium carbonate, and 3 g of a curing accelerator (dibutyltin dilaurylate) are added to the above viscous curable composition and mixed with a sealed stirrer until uniform. Defoaming was performed under reduced pressure for 10 minutes to obtain a room temperature curable composition of a white paste. Odor due to residual monomer was felt.

  The obtained curable composition was coated on a polyethylene plate so as to have a film thickness of 2.5 mm, and then cured for 7 days in an environment of 20 ° C. and a relative humidity of 50%. A film was obtained. The rubber properties of the sheet film were evaluated in the same manner as in Example 1. As a result, the elongation at break was 530% and the stress at break was 0.20 N / mm 2.

(Example 3)
During the preparation of the curable composition, 10 g of layered silicate Somasifu MPE-100 (swelling fluorinated mica organically treated with polyoxypropylene diethyl quaternary ammonium salt, manufactured by Co-op Chemical), tinuvin 770 (hindered amine light stabilizer, A curable composition was obtained in the same manner as in Example 1 except that 5 g of Ciba Specialty Chemicals Co., Ltd.) and 5 g of Tinuvin 327 (benzotriazole ultraviolet absorber, Ciba Specialty Chemicals Co., Ltd.) were added.

(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) plane spacing of stratified silicate, θ (degree) is a 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 [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. Irradiation with light was performed for 150 hours and 400 hours under the conditions, the surface state was visually confirmed, and those without cracks were determined as ◯.

-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)
Although the light irradiation evaluation by the eye super UV tester varies depending on the material system and test conditions, it cannot be generally stated. However, it is usually 10 times more severe than the evaluation by the sunshine weatherometer. Has been. The results are shown in Table 1 below.

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 (8)

It comprises a (meth) acrylic acid ester polymer (a) having a crosslinkable silyl group represented by the general formula (1) at the terminal and a compound (b) having a primary or secondary amino group. Curable composition.
_{^{- [Si (R 1) 2}} -b (Y) b O] m -Si (R 2) 3-a (Y) a (1)
(In the formula, R ¹ and R ² are all alkyl groups having 1 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms, or aralkyl groups having 7 to 20 carbon atoms, or (R ′) ₃ Si— ( R ′ represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, and three R ′ may be the same or different, and represents a triorganosiloxy group represented by R ¹ Alternatively, when two or more R ² are present, they may be the same or different, Y represents a hydroxyl group or a hydrolyzable group, and when two or more Y are present, they are the same. A may be 0 or 1, 2, or 3, and b may be 0, 1, or 2. m is an integer of 0 to 19, provided that a + mb ≧ 1 to be satisfied.)   The curable composition according to claim 1, wherein the residual (meth) acrylic acid ester monomer concentration in the composition is 0.5% by weight or less.   The curable composition according to claim 1, wherein the compound (b) having a primary or secondary amino group has a boiling point of 50 ° C. or more and 200 ° C. or less at 1 atmosphere.   The compound (b) having the primary or secondary amino group is blended in an amount of 0.1 to 20 parts by weight with respect to 100 parts by weight of the (meth) acrylic acid ester polymer (a). The curable composition according to any one of claims 1 to 3.   The curable composition according to any one of claims 1 to 4, further comprising a polyether polymer (c) having a hydrolyzable silyl group.   The curable composition according to any one of claims 1 to 5, further comprising a layered silicate.   A sealing material comprising the curable composition according to any one of claims 1 to 6. An adhesive comprising the curable composition according to claim 1.

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