JP3175886B2 - Method for producing curable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modified curable composition, and more particularly to a curable composition having remarkably excellent adhesion, weather resistance and mechanical properties.

[0002]

2. Description of the Related Art Various polymers having a hydrolyzable silicon group at the terminal, such as conventionally known as denatured silicone resins, are known as coating compositions and sealing compositions utilizing the characteristic that cured products have rubber elasticity. It is used for such purposes.

Known polymers having a terminal hydrolyzable silicon group are disclosed, for example, in JP-B-45-36319, JP-B-46-12154, and JP-B-49-32.
673, JP-A-50-156599, JP-A-51-73561, JP-A-54-6096, JP-A-55-82123, and JP-A-55-12.
3620, JP-A-55-125121, JP-A-55-131022, JP-A-55-1351
No. 35, JP-A-55-137129, and the like.

[0004]

All of these organic polymers have weaknesses in performance due to the structure of the main chain and the like. For example, the polymer described in JP-A-51-73561 has a urethane bond at the main chain and at the terminal, and therefore has poor weather resistance. Japanese Patent Laid-Open No. 50-
The polymer described in 156599 has insufficient adhesion to various adherends, and has a problem in weather resistance due to hydrogen atoms bonded to tertiary carbon because the main chain is polyether. is there.

In order to solve these drawbacks, JP-A-59-122541 proposes a composition comprising a polyether containing a reactive silicon group and a vinyl polymer having a reactive silicon group. Have been. According to this method, although the adhesiveness and weather resistance are improved to some extent, physical properties such as elongation and strength of the cured product are insufficient.

[0006]

DISCLOSURE OF THE INVENTION The present invention is intended to solve such a drawback, and uses a polyoxyalkylene polymer polymerized by using a specific catalyst as a main chain to improve weather resistance. An object of the present invention is to provide a method for producing a curable composition which is excellent and has excellent properties such as elongation. That is, at the terminal of a polyoxyalkylene polymer (D) having a number average molecular weight of 5,000 or more obtained by polymerizing an alkylene oxide with an initiator using a double metal cyanide complex (C) as a catalyst, a compound represented by the following general formula (1) is provided. Introduce at least 0.3 silicon-containing groups per molecule on average for all molecules
To produce an organic polymer (A) , and then , based on 100 parts by weight of the polymer , a polymerizable unsaturated group having at least one silicon-containing group represented by the following general formula (1) per polymer molecule. A method for producing a curable composition, comprising mixing 0.1 to 1000 parts by weight of a polymer (B) of a contained monomer . ^{_{-SiX a R 1 3-a ···}} (1) where the monovalent hydrocarbon group wherein R ¹ is a substituted or unsubstituted 1 to 20 carbon atoms, X is a hydrolyzable group, a is 1, 2
Or 3.

In the present invention, the polyoxyalkylene polymer (D) used as the main chain of the organic polymer (A) is an initiator such as a hydroxy compound having at least one hydroxyl group in the presence of the double metal cyanide complex (C). And a hydroxyl-terminated one produced by reacting the compound with an alkylene oxide.

By using the double metal cyanide complex (C), M _w / M _n is narrower than that of a polyoxyalkylene polymer produced using a conventional alkali metal catalyst,
It is possible to obtain a higher molecular weight, lower viscosity polyoxyalkylene polymer (D).

The complex metal cyanide complex (C) is preferably a complex containing zinc hexacyanocobaltate as a main component, and more preferably an ether and / or alcohol complex thereof. Its composition can be essentially the one described in JP-B-46-27250. As the ether, glymes such as glyme and diglyme are preferable, and glyme is particularly preferable from the handling during the production of the complex. As the alcohol, t-butanol described in JP-A-4-145123 is preferable.

The number of functional groups of the polyoxyalkylene polymer (D) is preferably 2 or more, and more preferably 2 to 4. Specific examples include a polyoxyethylene compound, a polyoxypropylene compound, a polyoxybutylene compound, a polyoxyhexylene compound, a polyoxytetramethylene compound, and / or a copolymer thereof.

Particularly preferred polyoxyalkylene polymers are polyoxypropylene diol, polyoxypropylene triol and polyoxypropylene tetraol. When used in the following methods (a) and (d), olefin-terminated polyoxyalkylene polymers such as allyl-terminated polyoxypropylene monol can also be used.

R ¹ in the general formula (1) is a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms, preferably an alkyl group having 8 or less carbon atoms, a phenyl group or a fluoroalkyl group. . Particularly preferred are a methyl group, an ethyl group, a propyl group, a propenyl group, a butyl group, a hexyl group, a cyclohexyl group, a phenyl group and the like.

X in the general formula (1) is a hydrolyzable group, for example, a halogen atom, an alkoxy group, an acyloxy group, an amide group, an amino group, an aminooxy group, a ketoximate group, an acid amide group, and a hydride group. . Among these, the carbon number of the hydrolyzable group having a carbon atom is preferably 6 or less, and particularly preferably 4 or less. Preferred hydrolyzable groups include lower alkoxy groups having 4 or less carbon atoms, especially methoxy, ethoxy, propoxy and propenyloxy groups.

A in the general formula (1) is 1, 2 or 3, and particularly preferably 2 or 3.

Next, a method for producing the organic polymer (A) will be described. The organic polymer (A) in the present invention is preferably produced by introducing a silicon-containing group into the terminal of a polyoxyalkylene polymer having a functional group as described below. Such compounds are liquid at room temperature, and
The cured product retains flexibility even at a relatively low temperature, and has preferable characteristics when used as a sealing material, an adhesive or the like.

(A) A method of reacting a polyoxyalkylene compound having a functional group with an olefin group introduced at a terminal thereof with a hydrosilyl compound represented by the following general formula (4). ^{_{HSiX a R 1 3-a ···}} (4) provided that wherein R ^1, X, a is as defined above. Here, as a method of introducing an olefin group, a method of reacting a compound having an unsaturated group and a functional group with a terminal hydroxyl group of a polyoxyalkylene compound, and bonding the compound with an ether bond, an ester bond, a urethane bond, a carbonate bond, or the like, Alternatively, when polymerizing an alkylene oxide, a method of adding an olefin group-containing epoxy compound such as allyl glycidyl ether and copolymerizing to add an olefin group to a side chain may be used.

(B) A method of reacting a compound represented by the following general formula (5) with a terminal of a polyoxyalkylene compound having a functional group. R ¹³ _-a SiX _a -R ⁵ NCO (5) wherein R ¹ , X and a are the same as above, and R ⁵ is a divalent hydrocarbon group having 1 to 17 carbon atoms.

(C) The terminal of the polyoxyalkylene compound having a functional group is reacted with a polyisocyanate compound such as tolylene diisocyanate to form an isocyanate group terminal, and the isocyanate group is represented by the following general formula (6). A method of reacting a W group of a silicon compound. ^{_{R 1 3-a -SiX a -R}} 5 W ··· (6) provided that wherein R ^1, R ^5, X, a are as defined above, W is a hydroxyl group, a carboxyl group, a mercapto group and an amino group (1 Active hydrogen-containing group selected from primary or secondary).

(D) An olefin group is introduced into the terminal of the polyoxyalkylene compound having a functional group, and the olefin group is reacted with a mercapto group of a silicon compound represented by the general formula (6) wherein W is a mercapto group. How to let.

The number of silicon-containing groups is 0.3 or more per molecule on the average of all molecules.

As the organic polymer (A) in the present invention, an organic polymer having a number average molecular weight of 5,000 to 30,000 can be used. The number average molecular weight of the organic polymer (A) is 500
When it is lower than 0, the cured product is hard and the elongation is low, and when the number average molecular weight exceeds 30,000, the flexibility and elongation of the cured product are not problematic, but the viscosity of the polymer itself becomes extremely high, Practicality decreases. The number average molecular weight is particularly preferably from 8,000 to 30,000.

The component (B) used in the present invention comprises a polymerizable unsaturated group-containing monomer (F) represented by the following general formula (2), a carbon-carbon double bond and the above-mentioned general formula (1). Compound containing a silicon-containing group (G)
It is preferably a polymer that can be produced by copolymerization with CH ₂ ＣC (R ² ) (R ³ ) (2) wherein R ² is a hydrogen atom, a halogen atom or a monovalent organic group having 1 to 10 carbon atoms, and R ³ is a 1 to 1 carbon atom. 20 is a monovalent organic group. It is.

Specific examples of the polymerizable unsaturated group-containing monomer (F) include styrene monomers such as styrene and α-methylstyrene; acrylic acid, methacrylic acid or their esters, and acrylic and methacrylic acids such as acrylamide and methacrylamide. A monomer containing a cyano group such as acrylonitrile or 2,4-dicyanobutene-1; a vinyl ester-based monomer such as vinyl acetate; a diene-based monomer such as isoprene, butadiene, or the like; a glycidyl group-containing monomer such as glycidyl acrylate or glycidyl methacrylate; And other olefins, unsaturated esters, halogenated olefins, vinyl ethers and the like.

The silicon compound (G) containing a carbon-carbon double bond and a silicon-containing group is represented by the following general formula (3). R ⁴ SiX _a R ¹³ _-a (3) wherein R ¹ , X and a are the same as above, and R ⁴ is an organic residue having a polymerizable unsaturated group.

Specific examples of the silicon compound (G) represented by the general formula (3) include vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyl Vinylsilanes such as trichlorosilane; acryloxysilanes such as 3-acryloxypropylmethyldimethoxysilane and 3-acryloxypropyltrimethoxysilane; methacryloxy such as 3-methacryloxypropylmethyldimethoxysilane and 3-methacryloxypropyltrimethoxysilane Although silane and the like can be mentioned, 3-methacryloxypropyltrimethoxysilane is particularly preferable. Other than these, for example, a polysiloxane compound having 2 to 30 silicon atoms, which has a silicon atom bonded to a C-C double bond and a hydrolyzable group, can be used.

The polymerizable unsaturated group-containing monomer (F) and the silicon compound (G) can be appropriately selected according to the purpose, but a cyano group-containing monomer such as acrylonitrile and an epoxy group-containing monomer such as glycidyl acrylate and glycidyl methacrylate. Use of a styrene-based monomer such as styrene or 3-methacryloxypropyltrimethoxysilane is preferable because particularly excellent adhesion and mechanical properties can be exhibited. In particular, when rubber elasticity is required after curing, it is preferable to use an acrylate ester.

In the present invention, one type of these polymerizable unsaturated group-containing monomers (F) may be used alone, or two or more types may be used in combination. Alternatively, the polymerizable unsaturated group-containing monomer (F) may be polymerized so that the olefin group remains on the side chain or terminal, and then reacted with the silicon compound (G).

The silicon compound (G) represented by the general formula (3) is compared with the polymerizable unsaturated group-containing monomer (F).
It is good to use in the range of 0.001 to 50% by weight,
When rubber elasticity is required after curing, it is preferably used in the range of 0.01 to 10% by weight, particularly preferably 0.1 to 5% by weight.

The polymerization of the polymerizable unsaturated group-containing monomer can be carried out by a usual method. As the polymerization initiator, various compounds capable of polymerizing a monomer having a polymerizable unsaturated group such as a radical generator can be used, and in some cases, polymerization can be performed by radiation or heat without using a polymerization initiator.
As the polymerization initiator, for example, peroxide-based, azo-based,
Alternatively, there are a redox-based polymerization initiator and a metal compound catalyst. Specific examples of frequently used polymerization initiators include, for example, azobisisobutyronitrile, benzoyl peroxide, t-alkylperoxyester, acetyl peroxide, diisopropylperoxycarbonate and the like. In addition, a solvent can be used if necessary.

In the present invention, a curing catalyst can be used if necessary. As the curing catalyst, a compound known as a catalyst for hydrolysis and condensation of a hydrolyzable silicon group can be used. Metal salts of carboxylic acids such as alkyl titanates, organosilicon titanates, tin octylate and dibutyltin dilaurate; amine salts such as dibutylamine-2-ethylhexoate; and other acidic catalysts and Basic catalysts can be used. The amount of the curing catalyst used is preferably in the range of 0.001 to 10 parts by weight based on 100 parts by weight of the total of the components (A) and (B).
It is preferred to use parts by weight.

The composition of the present invention may contain fillers, reinforcing agents, anti-sagging agents, adhesives and the like. As a filler,
Talc, clay, silica, etc .; carbon black, fine powder silica, etc. as reinforcing agents; inorganic pigments, such as iron oxide, chromium oxide, titanium oxide, etc .; and organic pigments, such as phthalocyanine blue, phthalocyanine green, etc .; Are organic acid-treated calcium carbonate, hydrogenated castor oil, calcium stearate, zinc stearate, finely divided silica, and the like; examples of the adhesive include aminosilane and epoxysilane.

In the present invention, a plasticizer can be optionally used. As the plasticizer, known plasticizers can be used, and specifically, dioctyl phthalate, dibutyl phthalate,
Phthalates such as butylbenzyl phthalate; aliphatic carboxylic esters such as dioctyl adipate, isodecyl succinate, dibutyl sebacate and butyl oleate; glycol esters such as pentaerythritol ester; trioctyl phosphate and tricresyl phosphate Epoxide plasticizers such as epoxidized soybean oil and benzyl epoxy stearate; chlorinated paraffins and the like can be used alone or as a mixture of two or more.

The composition of the present invention may further contain various known additives and the like. As the additive, an adhesion imparting agent such as a phenol resin and an epoxy resin, various antioxidants, an ultraviolet absorber and the like can be used.

The curable composition of the present invention comprises a sealing agent,
Can be used for waterproofing agents, adhesives, coatings, etc.,
In particular, it is suitable for applications requiring sufficient strength and high adhesiveness of the cured product itself.

[0035]

EXAMPLES The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples.

Reference Examples 1 and 2 show production examples of the organic polymer (A), and Reference Example 3 shows production examples of the organic polymer used in Comparative Examples. Next, Production Examples of the polymer (B) of the polymerizable unsaturated group-containing monomer will be described with reference to Reference Examples 4 and 5.

Reference Example 1 Polymerization of propylene oxide was carried out with a zinc hexacyanocobaltate glyme complex using a diethylene glycol-propylene oxide adduct having a molecular weight of 1,000 as an initiator according to the method described in JP-A-3-72527. A polyoxypropylene diol having an average molecular weight of 19000 was obtained, the terminal hydroxyl group was converted to an allyl ether group, and methyldimethoxysilane was added and reacted with chloroplatinic acid as a catalyst.
An organic polymer (P1) having six silicon-containing groups was obtained.

Reference Example 2 Propylene oxide was polymerized with a zinc hexacyanocobaltate glyme complex using a glycerin-propylene oxide adduct having a molecular weight of 1,000 as an initiator according to the method described in JP-A-3-72527. Polyoxypropylene triol having an average molecular weight of 15,000 was obtained, the terminal hydroxyl group was converted to an allyl ether group, and methyldimethoxysilane was added and reacted with chloroplatinic acid as a catalyst to obtain an organic compound having an average of 1.4 silicon-containing groups per molecule. A polymer (P2) was obtained.

Reference Example 3 Polyoxypropylene diol having a number average molecular weight of 4000 was reacted with bromochloromethane based on the method described in JP-B-61-49332, and the terminal hydroxyl group was further reacted with allyl chloride.
After the terminal allyl ether group, methyldimethoxysilane was subjected to an addition reaction using chloroplatinic acid as a catalyst to obtain an organic polymer (P3). The number average molecular weight of this organic polymer in terms of polyoxypropylene diol was 11,000.

Reference Example 4 Glycidyl methacrylate 6
0 g, acrylonitrile 30 g, 3-methacryloxypropyltrimethoxysilane 10 g, toluene 100 g as a solvent, azobisisobutyronitrile 1 as an initiator
g of the polymer (P4) in a N ₂ atmosphere at 90 ° C. for 4 hours to obtain a 50% solution of the polymer (P4).

Reference Example 5 n-butyl acrylate 95
g, 3-methacryloxypropyltrimethoxysilane 5
g of azobisisobutyronitrile as an initiator and polymerized at 90 ° C. for 5 hours under N ₂ atmosphere to obtain a polymer (P
5) was obtained.

[Examples 1 to 3 and Comparative Examples 1 and 2] Among the organic polymers P1 to P3 produced in Reference Examples 1 to 3, 100 parts by weight of the organic polymer shown in Table 1 were used. After mixing the produced polymer (P4) of the unsaturated group-containing monomer by weight shown in Table 1, toluene was distilled off. 150 parts by weight of calcium carbonate, 20 parts by weight of titanium oxide, 50 parts by weight of dioctyl phthalate, hydrogenated castor oil 5
Parts by weight, 1 part by weight of a phenolic antioxidant, 1 part by weight of aminosilane, and 1 part by weight of dibutyltin dilaurate were kneaded under the condition that moisture does not enter to obtain a curable composition.

A sheet having a thickness of 2 mm was prepared from these sheets, cured at 20 ° C. for 7 days, and further cured at 50 ° C. for 7 days.
The punching properties were measured with a No. 3 dumbbell [50% modulus (M ₅₀ ), strength at break (T _s ), elongation at break (E
_l )]. Further, the tensile shear strength with respect to aluminum was measured according to JIS H4000 A1050P. Table 1 shows the results.

Example 4 and Comparative Examples 3 and 4 Instead of P4, the polymer of the polymerizable unsaturated group-containing monomer produced in Reference Example 5 was used with respect to 100 parts by weight of the organic polymer shown in Table 1. Except for mixing, a curable composition was obtained in the same manner as in Examples 1 to 3. The dumbbell properties were measured as in Examples 1 to 3, and the sunshine weatherometer 200 was used.
The surface after 0 hour was observed. Table 2 shows the results.

[0045]

[Table 1]

[0046]

[Table 2]

[0047]

EFFECTS OF THE INVENTION A mixture of an organic polymer having a silicon-containing group produced by using a double metal cyanide complex and a polymer of a polymerizable unsaturated group-containing monomer of the present invention having a silicon-containing group is mixed. The resulting composition has an effect of exhibiting excellent mechanical properties as well as excellent adhesiveness and weather resistance as compared with conventionally known compositions .

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-194679 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 1/00-101/16 C08G 65 / 00-65/48

Claims (5)

(57) [Claims] 1. A the end of the double metal cyanide complex (C) a number average molecular weight of 5000 or more polyoxyalkylene polymer obtained by polymerizing an alkylene oxide to an initiator as a catalyst (D), the following general formula (1 The silicon-containing group represented by) is introduced in an amount of 0.3 or more per molecule on the average of all molecules.
To produce an organic polymer (A) , and then , based on 100 parts by weight of the polymer , a polymerizable unsaturated group having at least one silicon-containing group represented by the following general formula (1) per polymer molecule. A method for producing a curable composition, comprising mixing 0.1 to 1000 parts by weight of a polymer (B) of a contained monomer . ^{_{-SiX a R 1 3-a ···}} (1) where the monovalent hydrocarbon group wherein R ¹ is a substituted or unsubstituted 1 to 20 carbon atoms, X is a hydrolyzable group, a is 1, 2
Or 3. Wherein a complex double metal cyanide complex (C) is a main component of zinc hexacyanocobaltate, a manufacturing method of claim 1. Is wherein at least one alkylene oxide is selected ethylene oxide, propylene oxide and butylene oxide, prepared according to claim 1 or 2
How . 4. A polymer (B) of a polymerizable unsaturated group-containing monomer, comprising a polymerizable unsaturated group-containing monomer (F) represented by the following general formula (2), a carbon-carbon double bond and hydrolysis: The polymer according to claim 1 , 2 or 3, which is a polymer which can be produced by copolymerization with a silicon compound (G) having a functional group .
Construction method . CH ₂ ＣC (R ² ) (R ³ ) (2) wherein R ² is a hydrogen atom, a halogen atom or a monovalent organic group having 1 to 10 carbon atoms, and R ³ is a 1 to 1 carbon atom. 20 is a monovalent organic group. 5. The silicon compound (G) is one or more kinds represented by the following general formula (3).
Manufacturing method . R ⁴ SiX _a R ¹³ _-a (3) wherein R ¹ , X and a are the same as above, and R ⁴ is an organic residue having a polymerizable unsaturated group.