JPH06220317A - Production of curable composition - Google Patents

Abstract

PURPOSE:To obtain a curable composition containing a polymer dispersed in a polyether having silyl group. CONSTITUTION:This curable composition can be produced by polymerizing glycidyl methacrylate and acrylonitrile in toluene, mixing the polymer with a polyoxypropylene having terminal silyl group and distilling out the unreacted monomer and toluene. The content of the polymer in the composition can easily be varied.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to a method of making improved curable compositions. Especially excellent mechanical properties,
The present invention relates to a curable composition having adhesiveness and excellent workability.

[0002]

2. Description of the Related Art Polyethers having at least one reactive silyl group in the molecule are used for coating compositions, sealing compositions and the like, taking advantage of the fact that cured products have rubber elasticity. The strength of the cured product is insufficient for applications such as adhesives and waterproofing agents, which poses a practical problem.

For example, when this is used as an adhesive, there arises a problem that the shear adhesive strength is insufficient,
When used as a waterproofing agent, there arises a problem that the strength of the film is insufficient. However, when trying to improve the strength of the cured product in order to solve these problems,
Generally, a cured product becomes hard and brittle, and a sufficient elongation at break cannot be obtained. Further, depending on the composition, the viscosity becomes extremely high, which poses a practical problem.

The present inventor has proposed a composition of a polymer of a polyether having at least one reactive silyl group in the molecule and a polymer of a polymerizable unsaturated group-containing monomer to obtain a polymer of the polymerizable unsaturated group-containing monomer. By uniformly dispersing in the polyether, it is found that a curable composition that eliminates the above disadvantages, is excellent in workability, and gives a cured product that has both remarkably excellent mechanical strength and elongation at break is obtained, I applied for a patent (Japanese Patent Application No. 4-253861).
(See Japanese Patent Application Nos. 4-253862 and 4-253863).

A specific example of the method for producing such a curable composition is a method of polymerizing a polymerizable unsaturated group-containing monomer in a polyether containing at least one reactive silyl group in the molecule. However, this method has a drawback that the viscosity of the curable composition after polymerization is significantly increased when the polyether contains an unsaturated group. Further, when several curable compositions having different polymer contents were produced at the same time, the polymerization reaction had to be carried out in different reactors, which was very inefficient.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks and to provide a curable composition having excellent mechanical properties, adhesiveness and workability. It is a thing.

[0007]

SUMMARY OF THE INVENTION The present invention provides a polymerizable unsaturated unsaturated polymer which does not cause significant thickening even when a polyether having an unsaturated group is used and which can easily change the content of the polymer. An object of the present invention is to provide a method for producing a polyether compound having a polymer of a group-containing monomer uniformly dispersed in a system and having at least one reactive silyl group in the molecule.

That is, after polymerizing a polymerizable unsaturated group-containing monomer in a solvent to obtain a polymer uniformly dispersed in the solvent, a polymer containing a silyl group containing at least one reactive silyl group in the molecule is obtained. This is a method for producing a curable composition, which comprises mixing with ether and distilling off the solvent.

The silyl group-containing polyether containing at least one reactive silyl group in the molecule of the present invention has one or more reactive silyl groups in one molecule and the main chain is substantially a polyether chain. Is a polymer consisting of

For example, JP-A-3-43449, JP-A-3-47825, JP-A-3-72527, JP-A-3-79627, and JP-B-46-307.
No. 11, Japanese Patent Publication No. 45-36319, Japanese Patent Publication No. 4
It is a polymer proposed in Japanese Patent Laid-Open No. 6-17553, in which the main chain skeleton consists essentially of polyether. A method for producing such a polymer is exemplified in the above-mentioned document.

The reactive silyl group, like a silanol group or a hydrolyzable silyl group, is capable of promoting a high molecular weight polyether by causing a condensation reaction with moisture or a curing agent.

The polyether is obtained by reacting an initiator such as a hydroxy compound having at least one hydroxyl group with a monoepoxide such as alkylene oxide in the presence of a catalyst such as an alkali metal catalyst, a complex metal cyanide complex catalyst, and a metal porphyrin. It is a polyether having a functional group capable of introducing a reactive silyl group such as a hydroxyl group-terminated one to be produced. The functional group is particularly preferably a hydroxyl group, and the number of functional groups of the polyether having a functional group is preferably 2 or more, and particularly 2
Or 3 is preferable.

Particularly preferred polyethers are polyoxypropylene diols and polyoxypropylene triols. When used in the method (a) below, olefin-terminated polyethers such as allyl-terminated polyoxypropylene monool can also be used.

The reactive silyl group is preferably a silyl group represented by the general formula (1). —SiX _a R ¹ _3-a (1) In the formula, R ¹ is a monovalent hydrocarbon group (having 20 or less carbon atoms) or a halogenated hydrocarbon group (having 20 or less carbon atoms), and preferably having a carbon number. An alkyl group having 6 or less or a fluoroalkyl group. Particularly preferred is a lower alkyl group such as a methyl group or an ethyl group.

X is a hydroxyl group or a hydrolyzable group, and examples thereof include a halogen atom, an alkoxy group, an acyloxy group, an amide group, an amino group, an aminoxy group and a ketoximate group. Of these, the hydrolyzable group having a carbon atom preferably has 6 or less carbon atoms, and particularly preferably 4 or less carbon atoms.
A preferred hydrolyzable group is a lower alkoxy group having 4 or less carbon atoms, particularly a methoxy group or an ethoxy group. a is 1, 2 or 3, and particularly preferably 2 or 3.

The reactive silyl group represented by the general formula (1) is 50% on average in all terminal groups of the silyl group-containing polyether.
The content is preferably not less than 65%, more preferably not less than 65%.
The method of introducing the reactive silyl group represented by the general formula (1) into the polyether is not particularly limited, but it can be introduced, for example, by the following method.

(A) A method of reacting a terminal unsaturated group of a polyether with a hydrosilyl compound represented by the general formula (2). HSiX _a R ¹ _3-a (2) (wherein R ¹ , X and a are the same as above)

As a method for introducing an olefin group, a compound having an unsaturated group and a functional group is reacted with a terminal hydroxyl group of a polyether and bonded by an ether bond, an ester bond, a urethane bond or a carbonate bond. Alternatively, when the alkylene oxide is polymerized, a method of introducing an olefin group into the side chain by adding an olefin group-containing epoxy compound such as allyl glycidyl ether and copolymerizing the same can be mentioned.

(B) A method of reacting a polyether terminal hydroxyl group with a compound represented by the general formula (3). R ¹ _3-a —SiX _a —R ² —NCO (3) (wherein R ¹ , X, and a are the same as above. R ² has 1 to 1 carbon atoms.
A divalent hydrocarbon group of 7. )

The following compounds may be shown as the organosilicon compound represented by the general formula (3). (C ₂ H ₅ O) ₃ Si- (CH ₂ ) _3- NCO (CH ₃ O) ₃ Si- (CH ₂ ) ₃ -NCO (CH ₃ ) (CH ₃ O) ₂ Si- (CH ₂ ) _3- NCO (CH ₃ O) ₃ Si-NCO (CH ₃ O) ₂ Si (NCO) ₂

(C) After the end of the polyether is reacted with a polyisocyanate compound such as tolylene diisocyanate to form an isocyanate group end, the isocyanate group is reacted with the W group of the silicon compound represented by the general formula (4). How to make.

R ¹ _3-a -SiX _a -R ² W (4) (wherein R ¹ , R ² , X and a are the same as above. W is a hydroxyl group,
An active hydrogen-containing group selected from a carboxyl group, a mercapto group and an amino group (primary or secondary). )

(D) A method of introducing an olefin group into the end of the polyether and reacting the olefin group with the mercapto group of the silicon compound represented by the general formula (4) in which W is a mercapto group.

The molecular weight of the silyl group-containing polyether in the present invention is preferably 6000 to 50,000, more preferably 7,000 to 30,000, and especially 15,000 to 300.
00 is preferable.

The following compounds may be mentioned as specific examples of the polymerizable unsaturated group monomer in the present invention. In the case of (meth) allyl or (meth) acryl, the former means both allyl and methallyl, and the latter means both acryl and methacryl (hereinafter the same).

Epoxy group-containing monomer: unsaturated hydrocarbon oxide such as 1-vinylcyclohexane-3,4-epoxide and butadiene monoxide; unsaturated glycidyl ethers such as vinyl glycidyl ether and (meth) allyl glycidyl ether; glycidyl (Meth) acrylate, glycidyl crotonate, glycidyl cinnamate,
Glycidyl esters of unsaturated monocarboxylic acids such as glycidyl vinyl benzoate; monoalkyl monoglycidyl esters or diglycidyl esters of unsaturated dicarboxylic acids.

Reactive silyl group-containing monomer: γ- (meth) acryloxypropyltrimethoxysilane, γ-
Reactive silyl group-containing (meth) acryloxyalkyl compounds such as (meth) acryloxypropylmethyldimethoxysilane; reactions of vinylmethyldimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyl (β-methoxyethoxy) silane, etc. Vinyl compounds containing silyl groups.

Polymerizable monomer having a hydroxyl group: vinyl alcohol, (meth) allyl alcohol, crotyl alcohol, isocrotyl alcohol, 1-buten-3-ol, 2-buten-1-ol, 2-butene-1, Unsaturated monohydric or polyhydric alcohols such as 4-diol; N-alkylol acrylamides such as N-methylol acrylamide and N-ethylol acrylamide; hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate , Polyoxyethylene (meth) acrylic acid, polyoxypropyl (meth) acrylic acid, polyoxyethylene-polyoxypropylene (meth) acrylic acid and other polymerizable unsaturated carboxylic acid glycol esters.

Polymerizable monomer having amino group: N, N
-Unsaturated hydrocarbon amines such as dimethyl (meth) allylamine; unsaturated ether amines such as vinyl-N, N-dimethylaminoethyl ether; dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, 3- Amino group-containing unsaturated esters such as dimethylamino-2-hydroxypropyl (meth) acrylate, morpholinoethyl (meth) acrylate, and dimethylaminoethyl crotonate; Amino group-containing unsaturated amides such as dimethylaminopropyl (meth) acrylamide Unsaturated heterocyclic amines such as 2-vinylpyridine.

Other polymerizable functional group-containing monomer having a reactive functional group: equimolar reaction products of hydroxyethyl (meth) acrylate and organic diisocyanate or thioglycolic acid, acrylic acid, methacrylic acid and the like.

Other polymerizable unsaturated group-containing monomers: Styrene-based monomers such as styrene, α-methylstyrene and chlorostyrene; methyl (meth) acrylate, (meth)
Esters of (meth) acrylic acid such as ethyl acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and benzyl (meth) acrylate; amides of (meth) acrylic acid such as (meth) acrylamide. Acrylonitrile, etc .; Acrylonitrile, 2,4-dicyanobutene-1 and other cyano group-containing monomers; Vinyl acetate, vinyl propionate and other vinyl ester monomers; Butadiene, isoprene, chloroprene and other diene monomers; and others Olefins, unsaturated esters, halogenated olefins, vinyl ethers.

The type and combination of these polymerizable unsaturated group-containing monomers can be appropriately selected according to the purpose of modifying the cured product, but the polymer or copolymer is in the form of fine particles. It is necessary to be able to disperse uniformly and stably in a solvent and a silyl group-containing polyether.

When the polymer is compatible with the solvent or the silyl group-containing polyether and dissolves uniformly, problems such as a decrease in rubber elasticity of the cured product and an increase in the viscosity of the composition may occur. It becomes impossible to realize excellent mechanical properties and workability. Further, the fine particles of the polymer which can be uniformly dispersed in the polyether preferably have a glass transition point Tg of 50 ° C. or higher from the viewpoint of exhibiting excellent mechanical strength in the cured product.

From these points, specifically, a cyano group-containing monomer such as acrylonitrile as a main component,
It is preferable to use a glycidyl group-containing monomer such as glycidyl methacrylate and a styrene-based monomer such as styrene. In particular, when a glycidyl group-containing monomer is selected as the main component, excellent adhesion to various substrates can be imparted at the same time.

The polymer of the polymerizable unsaturated group-containing monomer may be used in the range of 0.1 to 100 parts by weight based on 100 parts by weight of the polyether containing at least one reactive silyl group in the molecule. From the viewpoint that the coalesced fine particles are uniformly dispersed in the polyether, it is preferably used in the range of 0.1 to 60 parts by weight, and particularly preferably in the range of 5 to 40 parts by weight. When the content of the polymer is large, the elongation at break of the cured product is significantly reduced depending on the composition.

The solvent used in the present invention can be appropriately selected according to the type of the unsaturated group-containing monomer used for the polymerization, but a solvent which can be uniformly dispersed without being dissolved in the polymer is selected. Is essential. As such a solvent, an aromatic organic solvent is preferable.

When a cyano group-containing monomer, a glycidyl group-containing monomer or a styrene-based monomer is used as the polymerizable unsaturated group-containing monomer in the present invention, it is particularly preferable to use toluene as the solvent.

For the polymerization of the polymerizable unsaturated group-containing monomer, specifically, a method of adding a radical-generating polymerization initiator and a polymerizable unsaturated group-containing monomer to a solvent and heating with stirring can be applied. The method of adding the polymerization initiator and the polymerizable unsaturated group-containing monomer is not particularly limited, a solvent, a polymerization initiator, a method of actively mixing the polymerizable unsaturated group-containing monomer,
A method of dropping a polymerizable unsaturated group-containing monomer in which a polymerization initiator is dissolved in a solvent can be appropriately used.

The polymerization initiator is not limited to the radical generator, and various compounds capable of polymerizing the polymerizable unsaturated group-containing monomer may be used. In some cases, the polymerization initiator may be used without radiation or radiation. It can be polymerized by heat. Examples of the polymerization initiator include peroxide-based, azo-based, or redox-based polymerization initiators and metal compound catalysts. Specific examples of the polymerization initiator often used include azobisisobutyronitrile, benzoyl peroxide, t-alkylperoxy ester, acetyl peroxide, diisopropyl peroxy carbonate and the like.

After the polymerization of the monomer is completed, the monomer is mixed with a polyether containing at least one reactive silyl group in the molecule, and then the solvent is distilled off while stirring under reduced pressure to obtain the desired polymerizable unsaturated. It is possible to obtain a polyether compound having a polymer of a group-containing monomer uniformly dispersed in the system and having at least one reactive silyl group in the molecule. The solvent may not be completely distilled off but may be left as it is.

In curing the curable composition of the present invention, a curing accelerating catalyst for accelerating the curing reaction of the reactive silyl group may be used. Alkyl titanates, organosilicon titanates, bismuth tris-2 are used as the curing acceleration catalyst.
-Metal salts of carboxylic acids such as ethylhexoate, tin octylate and dibutyltin dilaurate: amine salts such as dibutylamine-2-ethylhexoate: and other acidic and basic catalysts may be used. If necessary, the composition of the present invention further comprises a reinforcing agent, a filler, a plasticizer,
An anti-sagging agent may be included.

Carbon black, finely divided silica, etc. are used as the reinforcing agent, calcium carbonate, talc, clay, silica, etc. are used as the filler, and dioctyl phthalate, dibutyl phthalate, dioctyl adipate, chlorinated paraffin and petroleum-based materials are used as the plasticizer. Plasticizers, inorganic pigments such as iron oxide, chromium oxide, titanium oxide, and organic pigments such as phthalocyanine blue and phthalocyanine green are used as anti-sagging agents, organic acid-treated calcium carbonate, hydrogenated castor oil, calcium stearate, stearin. Examples thereof include zinc acid and fine powder silica.

The curable composition of the present invention comprises a sealing agent,
It can be used as a waterproofing agent, an adhesive, a coating agent, etc., and is particularly suitable for applications in which the cured product itself requires sufficient strength.

[0044]

【Example】

(Production Example 1) Polyoxypropylenediol was obtained by polymerizing propylene oxide with a zinc hexacyanocobaltate catalyst using diethylene glycol as an initiator.
Allyl chloride was added to this to convert the terminal hydroxyl group into an allyl group. Then, methyldimethoxysilane was reacted in the presence of a platinum catalyst to convert 100% of the terminal allyl group into a methyldimethoxysilyl group, and an average molecular weight of 2000
0 polyether A was obtained.

(Production Example 2) Propylene oxide was polymerized with zinc hexacyanocobaltate catalyst using diethylene glycol as an initiator to obtain polyoxypropylene diol. Allyl chloride was added to this to convert the terminal hydroxyl group into an allyl group. Then, methyldimethoxysilane was reacted in the presence of a platinum catalyst to convert 70% of the terminal allyl groups into methyldimethoxysilyl groups to obtain polyether B having an average molecular weight of 17,000.

(Examples 1 to 3) 100 g of toluene was placed in a four-necked flask and 30 g of monomer was added while keeping the temperature at 100 ° C.
A mixture of and 0.6 g of azobisisobutyronitrile was added dropwise over 2 hours with stirring under a nitrogen atmosphere.
Then, stirring was continued for 0.5 hours at the same temperature. After completion of the reaction, Xg of polyether A or polyether B was added and mixed by stirring, and then toluene and unreacted monomer were mixed with 1 while stirring.
The mixture was heated at 10 ° C. and 0.1 mmHg for 2 hours under reduced pressure for deaeration and distilled off to obtain a curable composition of interest. Table 1 shows the type of polyether and the type of monomer used, X, and the viscosity (unit: cps) of the obtained curable composition at 25 ° C.

COMPARATIVE EXAMPLE 1 Polyether B (50 g, 4)
A mixture of 50 g of the same polyether, 30 g of a monomer, and 0.6 g of azobisisobutyronitrile was placed in a two-necked flask while maintaining the temperature at 110 ° C. and added dropwise over 2 hours while stirring under a nitrogen atmosphere. Then, stirring was continued for 0.5 hours at the same temperature. After the reaction is completed, the unreacted monomer is heated to 110 ° C,
The target curable composition was obtained by degassing by heating under reduced pressure at 0.1 mmHg for 2 hours. Table 1 shows the types of polyether and the types of monomers used, and the viscosity (unit: cps) of the obtained curable composition at 25 ° C.

(Comparative Examples 2 and 3) Data of polyether A or polyether B alone are shown in Table 1 as Comparative Examples 2 and 3.

[0049]

[Table 1]

Dibutyltin dilaurate was added as a curing catalyst to the curable compositions obtained in Examples 1 to 4 and the polyethers of Comparative Examples 2 and 3 to prepare a 2 mm thick sheet at 20 ° C. for 7 days. The physical properties were measured after curing and curing at 50 ° C. for 7 days. The results are shown in Table 2. Further, the curable compositions obtained in Examples 1 to 4 and Comparative Examples 2 and 3
Dibutyltin dilaurate was added to the polyether as a curing catalyst, and the adhesion strength to mortar was tested in accordance with JIS-A5548, 5.3.3. The results are shown in Table 3.

[0051]

[Table 2]

[0052]

[Table 3]

[0053]

According to the present invention, a curable composition in which polymer particles are uniformly dispersed in a polyether having at least one reactive silyl group in the molecule can be obtained. According to the method of the present invention, even when the silyl group-containing polyether has an unsaturated group, no significant thickening is accompanied. further,
It was also easy to change the content of the polymer to be dispersed.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display area C09J 133/18 JDD 7921-4J

Claims (6)

[Claims] 1. A polymer having a polymerizable unsaturated group-containing monomer is polymerized in a solvent to obtain a polymer uniformly dispersed in the solvent, and then a silyl group-containing polypolymer containing at least one reactive silyl group in the molecule. A method for producing a curable composition, which comprises mixing with ether and further distilling off the solvent. 2. The method according to claim 1, wherein the solvent is an aromatic organic solvent. 3. The method according to claim 2, wherein the aromatic organic solvent is toluene. 4. The method according to claim 1, wherein the polymerizable unsaturated group-containing monomer is a monomer selected from a cyano group-containing monomer, a glycidyl group-containing monomer and a styrene-based monomer. 5. A polymer of a polymerizable unsaturated group-containing monomer 0.1 to 1 relative to 100 parts by weight of a silyl group-containing polyether.
The manufacturing method according to claim 1, comprising 100 parts by weight. 6. The silyl group-containing polyether has a molecular weight of 60.
The manufacturing method of Claim 1 which is 00-50000.