JP5158554B2 - Curable composition - Google Patents

Description

  The present invention relates to a curable composition.

A curable composition comprising a polymer having a hydrolyzable silicon group at the terminal of a polyoxyalkylene chain (also referred to as a modified silicone polymer) is cured by moisture to form a cured product having excellent rubber elasticity. Therefore, the curable composition is widely used as an adhesive, a coating agent, and a sealing material. Among them, a curable composition comprising a polymer having a methyldimethoxysilyl group at the end of a polyoxyalkylene chain is widely accepted as a sealing material and an adhesive because of its excellent elongation properties (patent document) 1). However, for applications that require long-term weather resistance and fast curability, the curable composition has a problem that weather resistance and fast curability are not sufficient.
As a method for improving the problems of such oxyalkylene polymers, a method of blending a methyldimethoxysilyl group-terminated oxyalkylene polymer with a (meth) acrylic acid ester polymer having a reactive silicon group has been proposed. (See Patent Document 2).
However, in the curable composition of Patent Document 2, the weather resistance is improved, but the curing rate is not sufficient.

Japanese Patent Laid-Open No. 03-072527 Japanese Patent Laid-Open No. 06-172631

An object of this invention is to provide the curable composition which was excellent in the weather resistance of hardened | cured material and was excellent in the cure rate.

As a result of intensive studies, the present inventors have found that an oxyalkylene polymer having a specific reactive silicon group containing a specific ratio or more of a specific trialkoxysilyl group and a (meth) acrylic acid ester having a specific reactive silicon group It discovered that the curable composition containing a polymer was excellent in the weather resistance of cured | curing material, and was excellent in the cure rate, and came to complete this invention.
That is, the present invention provides an oxyalkylene polymer (A) having a reactive silicon group represented by the following formula (2) and a (meth) acrylic polymer having a reactive silicon group represented by the following formula (2). A curable composition containing a combination (B), wherein the reactive silicon group (S1) represented by the formula (1) is contained in the reactive silicon group of the oxyalkylene polymer (A) having a reactive silicon group. ) And a (meth) acrylic polymer (B) having a reactive silicon group is a polymer containing a (meth) acrylic acid alkyl ester monomer unit as an essential component. ) Acrylic acid alkyl ester monomer unit is a (meth) acrylic acid alkyl ester monomer unit having 1 to 2 carbon atoms in the alkyl group, and an alkyl (meth) acrylate having 3 to 6 carbon atoms in the alkyl group. Ester amount Ri Do from the body unit, and an unsaturated group-containing monomer having a reactive silicon group, the carbon number of the alkyl group is 1 to 2 and (meth) acrylic acid alkyl ester monomer, carbon atoms of the alkyl group 3 a 6 of (meth) having been that the reactive silicon group obtained by polymerizing a monomer consisting of acrylic acid alkyl ester monomer (meth) acrylic polymer, an oxyalkylene polymer having a reactive silicon group 10 to 70 parts by mass of (meth) acrylic polymer (B) having a reactive silicon group with respect to 100 parts by mass of the total amount of (A) and the (meth) acrylic polymer (B) having a reactive silicon group A curable composition is provided.

-Si (OR) ₃ (1)
(In the formula, R is independently an organic group having 1 to 6 carbon atoms.)
-SiX ¹ _a R ¹ _3-a (2)
(In the formula, R ¹ is an optionally substituted monovalent organic group having 1 to 20 carbon atoms, X ¹ is a hydroxyl group or a hydrolyzable group, and a is an integer of 1 to 3. there. However, may be different or a plurality of R ¹ is each independently when R ¹ there are a plurality, the plurality of X ¹ may be the same or different when X ¹ is more present.)

Also, in the above curable composition, the monomer to be polymerized to have the reactive silicon group-containing (meth) acrylic polymer (B), the carbon number of the alkyl group is 1 to 2 ( The curing according to claim 1 , wherein the mass ratio of the (meth) acrylic acid alkyl ester monomer / (meth) acrylic acid alkyl ester monomer having 3 to 6 carbon atoms of the alkyl group is 97/3 to 40/60. A sex composition is provided.
Further, the present invention provides a monomer polymerized to the (meth) acrylic polymer (B) having a reactive silicon group, wherein the alkyl group has 1 to 2 carbon atoms (meth) acrylic acid alkyl ester. The mass ratio of the (meth) acrylic acid alkyl ester monomer having 3 to 6 carbon atoms in the body / alkyl group is 90/10 to 45/55, and provides the curable composition according to claim 1 or 2. .
Moreover, this invention is the said curable composition, R of the formula (1) in the reactive silicon group of the oxyalkylene polymer (A) which has the said reactive silicon group is a C1-C6 alkyl group. The content rate of a certain reactive silicon group (S1) is 50 to 100%, The curable composition in any one of Claims 1-3 is provided.
In the curable composition, the oxyalkylene polymer (A) having a reactive silicon group may have a trimethoxysilyl group content in the reactive silicon group of 50 to 100%. The curable composition in any one of 1-4 is provided.
Moreover, this invention provides the curable composition whose said reactive silicon group (S1) is a reactive silicon group represented by following formula (3) in the said curable composition.
-Si (OCH ₃ ) ₃ (3)
In the curable composition, the oxyalkylene polymer (A) having a reactive silicon group is represented by the following formula (4): a polymer having a polyoxyalkylene chain and a hydroxyl group. Provided is a curable composition which is a polymer (A1) obtained by subjecting a compound to a urethanization reaction.

X ¹ _a R ¹ _3-a Si—R ² —NCO (4)
^(Wherein, X 1, ^{R 1} is .a is the same as ^X 1, ^{R 1} in the formula (1) is an integer of 1-3. However, a plurality of ^{R 1 when R 1} there are a plurality may be the same or different from each other, a plurality of X ¹ may be the same or different when X ¹ is more present.)
In the curable composition, the present invention provides the reactive silicon group (S2) represented by the above formula (1) in the reactive silicon group of the (meth) acrylic polymer (B). A curable composition comprising 100% is provided.
In the curable composition, the present invention provides the curable composition wherein the reactive silicon group (S2) of the (meth) acrylic polymer (B) is a reactive silicon group represented by the above formula (3). A composition is provided.

  The curable composition of the present invention can form a cured product excellent in rubber elasticity by moisture curing, the weathered product has excellent weather resistance, and the curing speed when cured. The curable composition of the present invention is useful as a sealing material, an adhesive and the like used for various applications.

The oxyalkylene polymer (A) having a reactive silicon group used in the curable composition of the present invention is an oxyalkylene polymer (A) having a reactive silicon group represented by the following formula (2): The reactive silicon group contains 10 to 100% of the reactive silicon group (S1) represented by the formula (1).
-Si (OR) ₃ (1)
(In the formula, R is independently an organic group having 1 to 6 carbon atoms.)
-SiX ¹ _a R ¹ _3-a (2)
(In the formula, R ¹ is an optionally substituted monovalent organic group having 1 to 20 carbon atoms, X ¹ is a hydroxyl group or a hydrolyzable group, and a is an integer of 1 to 3. there. However, may be different or a plurality of R ¹ is each independently when R ¹ there are a plurality, the plurality of X ¹ may be the same or different when X ¹ is more present.)

The oxyalkylene polymer (A) having a reactive silicon group preferably has a main chain substantially consisting of a polyoxyalkylene chain. Here, that the main chain substantially consists of a polyoxyalkylene chain means that a small amount of other chemical structures may be included. As other chemical structures, for example, the chemical structure of the initiator for producing an oxyalkylene polymer and a linking group with a reactive silicon group are included in the oxyalkylene polymer. Examples include the structure. The oxyalkylene unit is preferably 50% by mass or more, and more preferably 80% by mass or more, based on the total mass of the oxyalkylene polymer (A) having a reactive silicon group.

In the formula (2), R ¹ is a monovalent organic group having 1 to 20 carbon atoms that may have a substituent. R ¹ is preferably an alkyl group having 8 or less carbon atoms, a fluoroalkyl group having 8 or less carbon atoms, or a phenyl group, more preferably an alkyl group having 1 to 6 carbon atoms, and a methyl group. Particularly preferred. When a plurality of R ¹ are present in the same molecule, the plurality of R ¹ may be the same as or different from each other.
In Formula (2), X ¹ is a hydroxyl group or a hydrolyzable group. Here, the hydrolyzable group refers to a substituent that is directly bonded to a silicon atom and can generate a siloxane bond by a hydrolysis reaction and / or a condensation reaction. Examples of the hydrolyzable group include a halogen atom, an alkoxy group, an acyloxy group, an alkenyloxy group, a carbamoyl group, an amino group, an aminooxy group, and a ketoximate group. When the hydrolyzable group has a carbon atom, the number of carbon atoms is preferably 6 or less, and more preferably 4 or less.

X ¹ is particularly preferably an alkoxy group having 4 or less carbon atoms or an alkenyloxy group having 4 or less carbon atoms, and particularly preferably a methoxy group or an ethoxy group. Incidentally, when the X ¹ there are a plurality in the same molecule, the plurality of X ¹ may be the same or different from each other.

R in the above formula (1) is, for example, a group selected from an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, a cycloalkyl group having 5 to 6 carbon atoms, and a phenyl group. Can be mentioned. Accordingly, examples of the OR group of the formula (1) include a methoxy group, an ethoxy group, a propoxy group, a propenyloxy group, and a phenoxy group. Of these, a methoxy group and an ethoxy group are preferable, and a methoxy group is more preferable.
The above formula (1) is preferably a group bonded to the polyoxyalkylene chain end via a divalent linking group (preferably a divalent organic group having 1 to 20 carbon atoms).

The oxyalkylene polymer (A) having a reactive silicon group has a faster hydrolysis and crosslinking rate by linking the reactive silicon group (S1) to the oxyalkylene polymer, and has fast curability even at room temperature. Can be obtained. In particular, in order to obtain high reactivity and fast curability, it is particularly preferable to use a trimethoxysilyl group as the reactive silicon group (S1).
The oxyalkylene polymer (A) having a reactive silicon group contains 10 to 100% of the reactive silicon group (S1) represented by the formula (1) in the reactive silicon group.
When the trialkoxysilyl group represented by the formula (1) is less than 10%, a sufficient curing rate cannot be obtained.

Moreover, in order to adjust a cure rate and physical property, as a reactive silicon group (S1) represented by Formula (1), 1 or more types which consist of a trimethoxysilyl group and a C2-C6 alkoxysilyl group. A trialkoxy group may be used in combination. In this case, the molar ratio in the case where a trimethoxysilyl group and one or more trialkoxy groups composed of an alkoxysilyl group having 2 to 6 carbon atoms are used in combination is within a preferable range of mechanical properties of the resulting curable composition. It can be determined appropriately so that it can be adjusted. For example, when two types of trimethoxysilyl group and triethoxysilyl group are used as the functional group of the silicon group-containing oxyalkylene polymer to be used, trimethoxysilyl group (TMS) and triethoxysilyl group (TES) in the entire polymer are used. ) Is preferably TMS / TES = 5/95 to 95/5. By setting TMS to 5 mol% or more of the total of both, the curing rate of the curable composition can be sufficiently increased, and a curable composition having excellent workability can be obtained, and TMS is reduced to 95% or less. By doing this, the curing rate can be adjusted.

The oxyalkylene polymer (A) having a reactive silicon group uses, as a raw material, an oxyalkylene polymer having a functional group at the molecular end, and the reactive silicon group is bonded to the molecular end via an organic group or directly. It is preferable to manufacture. The oxyalkylene polymer used as a raw material is preferably a hydroxyl-terminated polymer obtained by subjecting a cyclic ether to a ring-opening polymerization reaction in the presence of a catalyst and an initiator.

As the initiator, a compound having one or more active hydrogen atoms per molecule, for example, a hydroxy compound having one or more hydroxyl groups per molecule can be used. Examples of the initiator include ethylene glycol, propylene glycol, dipropylene glycol, butanediol, hexamethylene glycol, hydrogenated bisphenol A, neopentyl glycol, polybutadiene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, allyl alcohol, and methallyl alcohol. , Glycerin, trimethylolmethane, trimethylolpropane, pentaerythritol, and the like, and hydroxyl-containing compounds such as alkylene oxide adducts of these compounds.
An initiator can use only 1 type and can also use 2 or more types together.

When ring-opening polymerization of a cyclic ether in the presence of an initiator, a polymerization catalyst can be used. Examples of the polymerization catalyst include potassium compounds such as potassium hydroxide and potassium methoxide, and alkali metal compounds such as cesium compounds such as cesium hydroxide; double metal cyanide complexes; metal porphyrin complexes; and P = N bonds A compound etc. can be illustrated.

The polyoxyalkylene chain in the oxyalkylene polymer (A) having a reactive silicon group is preferably composed of polymerized units of oxyalkylene formed by ring-opening polymerization of an alkylene oxide having 2 to 6 carbon atoms. More preferably, it is composed of polymerized units of oxyalkylene formed by ring-opening polymerization of one or more alkylene oxides selected from the group consisting of oxide and butylene oxide, and polymerization of oxyalkylene formed by ring-opening polymerization of propylene oxide Particular preference is given to units. When the polyoxyalkylene chain is composed of two or more oxyalkylene polymer units, the arrangement of the two or more oxyalkylene polymer units may be block or random.

The method for producing the oxyalkylene polymer (A) having a reactive silicon group is not particularly limited, but the oxyalkylene polymer (A) having a reactive silicon group has a polyoxyalkylene chain and a hydroxy group. A polymer and a polymer obtained by urethanation of a compound having a group represented by the general formula (1) and an isocyanate group are preferable. When the oxyalkylene polymer is used, a curable composition having a higher curing rate can be obtained.
In the case of using a method of introducing a reactive silicon group at the molecular terminal by using an addition reaction of hydrosilane or mercaptosilane to an unsaturated group described below, an oxyalkylene polymer having an unsaturated group, for example, allyl alcohol is used. An allyl-terminated polyoxypropylene monool obtained by polymerizing alkylene oxide as an initiator can also be used.

  As for Mn of the oxyalkylene polymer (A) which has a reactive silicon group, 5000-30000 are preferable and 8000-25000 are especially preferable. Further, the Mw / Mn of the polymer is preferably 3.0 or less, more preferably 1.6 or less, and particularly preferably 1.5 or less. In order to obtain an oxyalkylene polymer (A) having a reactive silicon group with a small Mw / Mn, it can be obtained by polymerizing a cyclic ether in the presence of an initiator, particularly using the following composite metal cyanide complex as a catalyst. It is particularly preferable to use an oxyalkylene polymer, and the method of modifying the terminal of such a raw material oxyalkylene polymer into a reactive silicon group is most preferable.

The oxyalkylene polymer (A) having a reactive silicon group has the above reactive silicon group at least at a part of its molecular terminals, and at least one, preferably 1.1 to 5, more preferably in the molecule. Preferably it has 1.1 to 3 reactive silicon groups. When the number of silicon groups in one molecule is less than one, a curable composition having sufficient hardness and curability may not be obtained, and when the number of reactive silicon groups exceeds 5, it was used. The elongation of the cured product obtained from the curable composition may be insufficient.

The method for introducing a reactive silicon group into the terminal group of a hydroxyl-terminated oxyalkylene polymer (hereinafter also referred to as a raw material oxyalkylene polymer) obtained by ring-opening polymerization of a cyclic ether in the presence of an initiator is not particularly limited. In general, a method of producing an oxyalkylene polymer (A) having a reactive silicon group by further connecting a reactive silicon group to the terminal group via an organic group is preferred. The oxyalkylene polymer (A) having a reactive silicon group obtained by using this production method has a group represented by the following formula (5), and is a group represented by the formula (5). 10 to 100% is a group represented by the formula (6).
^{_{-R 2 -SiR 1 3-a X}} 1 a ·· (5)
—R ² —Si (OR) ₃ ... (6)
In the above formula (5), R ¹ , X ¹ and a are the same as in the above (2), and in the formula (6), R is the same as R in the above formula (1). R ²
Is a divalent organic group, preferably a divalent hydrocarbon group having 1 to 17 carbon atoms, and particularly preferably a trimethylene group (—CH ₂ CH ₂ CH ₂ —).

Examples of the method for introducing a reactive silicon group into the raw material oxyalkylene polymer through the organic group R ² as described above include the following methods (a) to (d). In order to obtain a polymer in which 10 to 100% of the reactive silicon group represented by the formula (5) is the reactive silicon group represented by the following formula (6), the following (a) to (b) According to (d), a polymer having a group represented by the formula (5) other than the formula (6) at the molecular terminal and a polymer having a group represented by the formula (6) at the molecular terminal, respectively, What is necessary is just to mix. Further, according to the following (A) to (D), a silicon compound corresponding to the group represented by the formula (5) other than the formula (6), and a silicon compound corresponding to the group represented by the formula (6) The silicon compound corresponding to the group represented by formula (6) can be used at the same time to modify the terminal of the raw material oxyalkylene polymer. In the polymer (A), 10 to 100% of the reactive silicon groups represented by the formula (5) is a reactive silicon group represented by the following formula (6). 100% is particularly preferred.

(A) A method in which an unsaturated group is introduced at the end of a raw material oxyalkylene polymer having a hydroxyl group, and then a reactive silicon group is bonded to the unsaturated group. Examples of this method include the following two methods (A-1) and (A-2).
(A-1) A method using a so-called hydrosilylation reaction in which a hydrosilyl compound represented by the following formula (7) is reacted with the unsaturated group in the presence of a catalyst such as a platinum compound.
HSiR ¹ _3-a X ¹ _a (7)
In the above formula ^{(7), R 1, X} 1 and a are as defined above (2).

(I-2) A method of reacting a mercaptosilane compound represented by the following formula (8) with an unsaturated group.
R ¹ _3-a X ¹ _a Si—R ² —SH (8)
In the formula ^{(8), R 1, X} 1 and a are as defined above (2). R ² is a divalent organic group having 1 to 20 carbon atoms, preferably a divalent hydrocarbon group having 1 to 17 carbon atoms, and particularly preferably a trimethylene group (—CH ₂ CH ₂ CH ₂ —). It is.
Examples of the mercaptosilane compound represented by the above formula (8) include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyltriisopropenyloxysilane, 3-mercaptopropylmethyldimethoxysilane, Examples include 3-mercaptopropyldimethylmonomethoxysilane and 3-mercaptopropylmethyldiethoxysilane.

  When reacting an unsaturated group with a mercapto group, a compound such as a radical generator used as a radical polymerization initiator may be used. If desired, the reaction is performed by radiation or heat without using a radical polymerization initiator. May be. Examples of the radical polymerization initiator include peroxide-based, azo-based, and redox-based polymerization initiators, and metal compound catalysts. Specifically, 2,2′-azobisisobutyronitrile, 2, Examples thereof include 2′-azobis-2-methylbutyronitrile, benzoyl peroxide, tert-alkyl peroxy ester, acetyl peroxide, and diisopropyl peroxy carbonate. When an unsaturated group and a mercapto group are reacted using a radical polymerization initiator, the reaction temperature is generally 20 to 200 ° C., preferably 50 to 150 ° C., depending on the decomposition temperature (half-life temperature) of the polymerization initiator. Thus, it is preferable to carry out the reaction for several hours to several tens of hours.

  As a method for introducing an unsaturated group at the terminal of the raw material oxyalkylene polymer, a functional group that can be linked to the terminal hydroxyl group of the raw material oxyalkylene polymer by an ether bond, an ester bond, a urethane bond, a carbonate bond, or the like. Examples thereof include a method in which a reactive agent having both groups is reacted with a raw material oxyalkylene polymer. In addition, when a cyclic ether is polymerized in the presence of an initiator, an unsaturated group is introduced into at least a part of the terminal of the raw material oxyalkylene polymer by copolymerizing an unsaturated group-containing epoxy compound such as allyl glycidyl ether. A method can also be used. The reaction is preferably performed at a temperature of 60 to 120 ° C., and the hydrosilylation reaction generally proceeds sufficiently within a reaction time of several hours.

(B) A method in which a raw material oxyalkylene polymer having a hydroxyl group at the terminal is reacted with an isocyanate silane compound having a reactive silicon group represented by the following formula (9).
_{^{R 1 3-a X 1 a}} Si-R 2 - NCO ·· (9)
In the above formula ^{(9), R 1, X} 1 and a are as defined above (2). R ² is a divalent organic group, preferably a divalent hydrocarbon group having 1 to 17 carbon atoms, and particularly preferably a trimethylene group. Examples of the compound represented by the formula (9) include 1-isocyanate methyltrimethoxysilane, 1-isocyanatemethyltriethoxysilane, 1-isocyanatepropyltrimethoxysilane, 1-isocyanatepropyltriethoxysilane, and 3-isocyanatepropyltrimethoxysilane. Silane, 3-isocyanatopropyltriethoxysilane, 1-isocyanatomethylmethyldimethoxysilane, 1-isocyanatemethyldimethylmonomethoxysilane, 1-isocyanatemethylmethyldiethoxysilane, 1-isocyanatopropylmethyldimethoxysilane, 1-isocyanatopropyldimethylmono Methoxysilane, 1-isocyanatopropylmethyldiethoxysilane, 3-isocyanatopropylmethyldimethoxysilane, 3-iso Isocyanate silane compound such as A sulfonate dimethyl monomethoxy silane and 3-isocyanate propyl methyl diethoxy silane, can be exemplified. Among these, 3-isocyanatopropyltrimethoxysilane and 1-isocyanatomethylmethyldimethoxysilane are more preferable, and 3-isocyanatepropyltrimethoxysilane is particularly preferable.

In the present invention, the reaction is carried out so that the isocyanate group (NCO) of the isocyanate silane compound has a molar ratio of NCO / OH = 0.80 to 1.05 with respect to the hydroxyl group (OH) of the raw material oxyalkylene polymer. Preferably it is done. Since this method has a small number of manufacturing steps, the process time can be greatly shortened, there are no impurities by-produced during the manufacturing process, no complicated operation such as purification is required, and the silicon group-containing oxy-acid obtained by this method is also available. The feature that the storage stability of the room temperature curable resin composition containing an alkylene polymer is excellent can be obtained.
A more preferable ratio of NCO groups to OH groups is NCO / OH (molar ratio) = 0.85 to 1.00. When the NCO ratio is small, a reaction between the remaining OH group and the alkoxysilyl group occurs, which is not preferable for storage stability. In such a case, it is preferable to react with an isocyanate silane compound or a monoisocyanate compound newly, consume excess OH groups, and adjust to a predetermined silylation rate.

When the hydroxyl group of the raw material oxyalkylene polymer is reacted with the compound of the above formula (9), a known urethanization reaction catalyst may be used. Although the reaction temperature and the reaction time required for completion of the reaction vary depending on whether or not the urethanization catalyst is used and the amount used, the reaction is generally carried out at a temperature of 20 to 200 ° C., preferably 50 to 150 ° C. for several hours. preferable.

(C) A polyisocyanate compound is reacted with an oxyalkylene polymer having a hydroxyl group at the molecular terminal under an excess of isocyanate groups to produce an oxyalkylene polymer having an isocyanate group at at least a part of the terminal. A method of reacting a W group of a silicon compound represented by the following formula (10).
R ¹ _3-a X ¹ _a Si—R ² —W (10)

In the above formula ^{(10), R 1, X} 1 and a are as defined above (2). R ² is a divalent organic group, preferably a divalent hydrocarbon group having 1 to 17 carbon atoms, and particularly preferably a trimethylene group. W represents an active hydrogen-containing group selected from the group consisting of a hydroxyl group, a carboxyl group, a mercapto group, a primary amino group, and a secondary amino group. Examples of the silicon compound represented by the formula (10) include N-phenyl-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, and N-phenyl-3-aminopropyl. Aminosilane compounds such as methyldimethoxysilane, 3-aminopropylmethyldimethoxysilane, and 3-aminopropylmethyldiethoxysilane; and mercaptosilane compounds such as 3-mercaptopropyltrimethoxysilane and 3-mercaptopropylmethyldimethoxysilane Can be illustrated.
When reacting the hydroxyl group of the raw material oxyalkylene polymer with the compound of the above formula (10), a known urethanization reaction catalyst may be used. Although the reaction temperature and the reaction time required for completion of the reaction vary depending on whether or not the urethanization catalyst is used and the amount used, the reaction is generally carried out at a temperature of 20 to 200 ° C., preferably 50 to 150 ° C. for several hours. preferable.

The (meth) acrylic polymer (B) having a reactive silicon group used in the curable composition of the present invention contains a (meth) acrylic acid alkyl ester monomer unit as an essential component in its main chain, A polymer having a reactive silicon group represented by the following formula (2) is preferred.
-SiX ¹ _a R ¹ _3-a (2)
In the above formula (2), X ¹ , a and R ¹ are the same as in the case of the oxyalkylene polymer (A). The main chain may be a polymer containing only a (meth) acrylic acid alkyl ester monomer unit as a monomer unit, or may be a polymer further containing an unsaturated group-containing monomer other than this. May be.

  The polymer containing a (meth) acrylic acid alkyl ester monomer unit means a polymer having a repeating unit composed of a (meth) acrylic acid alkyl ester, and the polymer is usually an alkyl (meth) acrylate. It produces | generates by superposing | polymerizing the polymerizable unsaturated group containing monomer which has an ester monomer as an essential component. In the present invention, the polymerizable unsaturated group-containing monomer is a compound having a polymerizable unsaturated bond (preferably a carbon-carbon double bond) and capable of forming a polymer. The (meth) acrylic acid alkyl ester means an acrylic acid alkyl ester or a methacrylic acid alkyl ester.

Furthermore, in the present invention, the reactive silicon group of the (meth) acrylic polymer (B) preferably contains 10 to 100% of a reactive silicon group (S2) represented by the following formula (1).
-Si (OR) ₃ (1)
In said formula (1), R is the same as that of the said oxyalkylene polymer (A).
It is more preferable that the reactive silicon group (S2) of the (meth) acrylic polymer (B) is a reactive silicon group represented by the following formula (3).
-Si (OCH ₃ ) ₃ (3)

In the present invention, the reactive silicon group of the (meth) acrylic polymer (B) having a reactive silicon group contains 1 to 3 hydroxyl groups or hydrolyzable groups, but has a fast curing rate. In order to obtain a product, the trialkoxysilyl group represented by the formula (1) is preferably 10% or more, and the trialkoxysilyl group is more preferably a trimethoxysilyl group. When the trialkoxysilyl group represented by the following formula (1) is less than 10%, a sufficient curing rate cannot be obtained. By including a trialkoxysilyl group, the curing rate tends to be further increased.

The (meth) acrylic polymer (B) in the present invention contains a (meth) acrylic acid alkyl ester monomer represented by the following general formula (11) as a monomer unit.
CH ₂ = CR ⁴ COOR ⁵ (11)
In Formula (11), R ⁴ is a hydrogen atom or a methyl group, and R ⁵ is an alkyl group that may be substituted with a hydrocarbon group. R ⁵ may be a linear or branched alkyl group or an alkyl group having a cyclic structure such as a cycloalkylalkyl group. R ⁵ may be substituted with a hydrocarbon group other than an alkyl group such as an aryl group.

  As long as the (meth) acrylic polymer (B) contains the (meth) acrylic acid alkyl ester monomer represented by the formula (11) as a monomer unit, The number is not limited. For example, only one or two or more (meth) acrylic acid alkyl ester monomers represented by the formula (11) may be used as a monomer unit, or other than the monomer. One type or two or more types of saturated group-containing monomers may be further included as monomer units. The ratio of the monomer unit derived from the (meth) acrylic acid alkyl ester monomer represented by the formula (11) is 30% by mass or more with respect to the entire (meth) acrylic acid alkyl ester copolymer. Is preferable, and it is more preferable that it is 50 mass% or more.

(Meth) acrylic polymer (B), the (meth) acrylic acid alkyl ester monomer unit, the number of carbon atoms in the alkyl group 1 to 2 (meth) acrylic acid alkyl ester monomer unit, an alkyl group It is a polymer composed of (meth) acrylic acid alkyl ester monomer units having 3 to 6 carbon atoms . That is, the (meth) acrylic acid alkyl ester copolymer is a (meth) acrylic acid alkyl ester monomer having a repeating unit composed of a (meth) acrylic acid alkyl ester monomer and having an alkyl group having 1 to 2 carbon atoms. And a (meth) acrylic acid alkyl ester monomer unit having 3 to 6 carbon atoms in the alkyl group .

Specific examples of the (meth) acrylic acid alkyl ester monomer in the present invention include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and (meth) acrylic acid. -n-butyl, isobutyl (meth) acrylate, (meth) -tert- butyl acrylate, and (meth)-n-hexyl acrylate.

In the case where the (meth) acrylic acid alkyl ester monomer having 1 to 2 carbon atoms in the alkyl group and the (meth) acrylic acid alkyl ester monomer having 3 to 6 carbon atoms in the alkyl group are used in combination, (Meth) acrylic acid alkyl ester monomer having 1 to 2 carbon atoms / (meth) acrylic acid alkyl ester monomer having 3 to 6 carbon atoms (mass ratio) is 97/3 to 40 / 60, more preferably 90/10 to 45/55, still more preferably 80/20 to 50/50, and particularly preferably 75/25 to 50/50 .

The (meth) acrylic polymer (B) in the present invention is, for example, the above-mentioned unsaturated group-containing monomer having a (meth) acrylic acid alkyl ester monomer as an essential component, radical polymerization, anionic polymerization, cationic polymerization. It is obtained by polymerizing by the above. In particular, radical polymerization is preferable, and the form thereof may be any of solution polymerization, emulsion polymerization, suspension polymerization, and bulk polymerization.
When a (meth) acrylic acid alkyl ester copolymer is produced by radical polymerization, a polymerization initiator is usually added as a radical generating source to the unsaturated group-containing monomer. As the polymerization initiator, the same ones as mentioned in the description of the reaction between the polyoxyalkylene chain-containing polymer having an unsaturated group and the mercapto compound are used. In addition, when activating by a radiation or a heat | fever, a polymerization initiator is not necessarily required. The reaction is preferably performed at 20 to 200 ° C. (preferably 50 to 150 ° C.) for several hours to several tens of hours.

In radical polymerization, a chain transfer agent may be used for the purpose of controlling the molecular weight.
Examples of the chain transfer agent include alkyl mercaptans such as n-dodecyl mercaptan, t-dodecyl mercaptan, and n-butyl mercaptan, α-methylstyrene dimer, and the like.
A curable composition can be prepared by preparing a (meth) acrylic acid alkyl ester copolymer in advance by a method such as radical polymerization and mixing it with other components. Alternatively, an unsaturated group-containing monomer may be polymerized in the presence of other components in the curable composition to produce a (meth) acrylic acid alkyl ester copolymer. In this case, it is preferable to polymerize the unsaturated group-containing monomer in the presence of the oxyalkylene polymer (A). Thereby, the mixing step can be omitted, and it becomes easy to uniformly disperse the (meth) acrylic acid alkyl ester copolymer in the oxyalkylene polymer (A). Furthermore, in the polymerization process, a part of the unsaturated group-containing monomer may be graft-polymerized to the oxyalkylene polymer (A) having a reactive silicon group. In this case, the graft polymer functions as a compatibilizing agent, and the dispersibility of the (meth) acrylic acid alkyl ester copolymer is further improved.

Examples of the method for introducing a reactive silicon group into the (meth) acrylic polymer include the following methods (i), (ii), (iii) and (iv). A plurality of methods selected from these methods may be combined.
(I): When a (meth) acrylic polymer is synthesized by polymerization of an unsaturated group-containing polymer, the unsaturated group-containing monomer having a reactive silicon group represented by the formula (2) is copolymerized. Method.
(Ii): A method of using a chain transfer agent having a reactive silicon group represented by formula (2) when a (meth) acrylic polymer is synthesized by polymerization of an unsaturated group-containing polymer.
(Iii): A method of using an initiator having a reactive silicon group represented by formula (2) when a (meth) acrylic polymer is synthesized by polymerization of an unsaturated group-containing polymer.
(Iv): A (meth) acrylic polymer having a functional group such as a hydroxyl group, an amino group, a carboxyl group, an isocyanate group, or an epoxy group is synthesized, and a functional group that reacts with the functional group and the formula (2) A method of reacting a compound having a reactive silicon group.

  Examples of the unsaturated group-containing monomer having a reactive silicon group represented by the formula (2) used in the method (i) include vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldichlorosilane, Vinyl silanes such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, tris (2-methoxyethoxy) vinylsilane; 3-acryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, 3-acryloyloxypropyltri (Meth) acryloylo such as methoxysilane, 3-acryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane Shishiran and the like. These can be used alone or in combination of two or more.

The amount of the unsaturated group-containing monomer having a reactive silicon group is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of all monomers used for the synthesis of the acrylic polymer. 18 mass parts is more preferable, 0.1-15 mass parts is still more preferable, and 0.5-12 mass parts is especially preferable.
Examples of the chain transfer agent having a reactive silicon group used in the method (ii) include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltriethoxysilane, and 3-mercaptopropyl. Mercapto compounds having a reactive silicon group such as methyldiethoxysilane and 3-mercaptopropyltriisopropenyloxysilane, (CH ₃ O) ₃ Si—S—S—Si (OCH ₃ ) ₃ , (CH ₃ O) _{3 Si- (CH 2) 3 -S-} S- (CH 2) 3 -Si (OCH 3) 3 and the like.

The (meth) acrylic polymer (B) having a reactive silicon group obtained by the production methods (ii) to (iv) of the (meth) acrylic polymer has a reactive silicon group in a part of the molecule. And having at least 0.4, preferably 0.5 to 5, more preferably 0.5 to 2 reactive silicon groups in the molecule.
In the present invention, the number average molecular weight Mn of the (meth) acrylic polymer (B) having a reactive silicon group is preferably 500 to 100,000, and preferably 1,000 to 30,000 in terms of polystyrene-reduced number average molecular weight by the GPC method. Is more preferable. When the Mn of the (meth) acrylic polymer (B) having a reactive silicon group exceeds 100,000, the workability tends to decrease, and when the Mn is less than 500, the physical properties of the curable composition tend to decrease. It is in.

In the present invention, the reactive silicon group of the (meth) acrylic polymer (B) having a reactive silicon group is the reactive silicon group of the oxyalkylene polymer (A) when the curable composition is cured. It is thought that the mechanical strength of the curable composition after curing is improved by reacting with the compound. Moreover, the weather resistance of the curable composition and the cured product thereof is also improved.
In the present invention, the (meth) acrylic polymer (B) having a reactive silicon group preferably has a reactive silicon group at the terminal. Thereby, it becomes possible to further improve the elongation characteristics after curing of the curable composition. Such a (meth) acrylic acid alkyl ester copolymer (B) having a reactive silicon group at the terminal can be obtained by, for example, the method (ii) or the method (iii).

In the curable composition, from the viewpoint of improving the weather resistance, the (meth) acrylic polymer (B) having a reactive silicon group is used as the (meth) acrylic polymer having a oxyalkylene polymer (A) and a reactive silicon group. It contains 10-70 mass parts with respect to 100 mass parts of total amounts of a union (B) , and it is more preferable to contain 20-60 mass parts.
When the ratio of the (meth) acrylic polymer (B) having a reactive silicon group in the present invention is less than 10 parts by mass, the physical properties of the curable composition tend to be lowered. The viscosity of the composition tends to increase and workability tends to decrease.

The curable composition of the present invention is preferably added with other additives as required, for example, a curing catalyst, an adhesion-imparting agent, and a filler, and mixed, and further, a plasticizer, a dehydrating agent, and an anti-aging agent. , And an additive selected from a colorant and the like may be optionally added. What is necessary is just to select the compounding quantity of various additives suitably.

As the curing catalyst, the crosslinking reaction of the reactive silicon group contained in the oxyalkylene polymer (A) and the (meth) acrylic polymer (B) having a reactive silicon group in the present invention is a compound that accelerates the reaction. Although it proceeds even if it does not exist, a curing catalyst is used to develop a practically sufficient curing rate.

Curing catalysts include divalent tin compounds such as tin 2-ethylhexanoate, tin naphthenate, and stearate; dialkyltin dicarboxylates such as dibutyltin dilaurate, dibutyltin diacetate, dibutyltin monoacetate, dibutyltin malate, and dialkoxy Organotin carboxylates such as tin monocarboxylate, tin chelate compounds such as dialkyltin bisacetylacetonate and dialkyltin monoacetylacetonate monoalkoxide, reaction products of dialkyltin oxide and ester compounds, dialkyltin oxide and alkoxysilane compounds And tetravalent tin compounds such as dialkyltin dialkyl sulfide.

Examples of tin chelate compounds include dibutyltin bisacetylacetonate, dibutyltin bisethylacetoacetate, dibutyltin monoacetylacetonate monoalkoxide, and the like. Examples of the reaction product of dialkyl tin oxide and an ester compound include tin compounds in which dibutyl tin oxide and a phthalate such as dioctyl phthalate or diisononyl phthalate are mixed by heating and reacted to form a liquid. In this case, as the ester compound, aliphatic and aromatic carboxylic acid esters other than phthalic acid esters, tetraethyl silicate and partial hydrolysis condensates thereof can be used. Further, compounds obtained by reacting or mixing these tin compounds with low-molecular alkoxysilanes or the like can also be preferably used.

Moreover, as a curing catalyst other than a tin compound, divalent bismuth compounds such as organic carboxylic acid bismuth salts; acidic compounds such as phosphoric acid, p-toluenesulfonic acid, phthalic acid, di-2-ethylhexyl phosphate; butylamine, Aliphatic monoamines such as hexylamine, octylamine, decylamine, laurylamine, N, N-dimethyl-octylamine, aliphatic polyamine compounds such as ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, aromatic Amine compounds such as amine compounds, alkanolamines, aminosilane coupling agents such as N- (2-aminoethyl) -3-aminopropyltrimethoxysilane and 3-aminopropyltrimethoxysilane, and organic titanate compounds. It is below. A divalent tin compound or a divalent bismuth compound is preferably used in combination because the curing acceleration effect is improved when used in combination with a primary amine compound. The above curing catalysts can be used alone or in combination of two or more. When the curing catalyst is used, the addition amount of the curing catalyst is 0.1 to 10 with respect to 100 parts by mass in total of the oxyalkylene polymer (A) and the (meth) acrylic polymer (B) having a reactive silicon group. It is preferable to set it as a mass part.

Examples of the adhesion imparting agent include silane coupling agents such as (meth) acryloyloxy group-containing silanes, amino group-containing silanes, mercapto group-containing silanes, epoxy group-containing silanes, and carboxyl group-containing silanes.

The above compounds may be used alone or in combination of two or more. As for the usage-amount of a silane coupling agent, 0-30 mass parts is preferable with respect to 100 mass parts of a polymer.

As an adhesiveness imparting agent, an epoxy resin and, if desired, an epoxy resin and an epoxy resin curing agent may be used in combination. When adding an epoxy resin to a curable composition, the usage-amount is 100 mass parts or less with respect to 100 mass parts of silicon group containing oxyalkylene polymers. When the usage-amount of an epoxy resin exceeds 100 mass parts, the hardness of the hardened | cured material obtained may be high and a softness | flexibility may become small too much.
The amount of the epoxy resin curing agent used is preferably 300 parts by mass or less with respect to 100 parts by mass of the epoxy resin.

A known filler can be used as the filler, but it is not necessary to use it. Specific examples of the filler include the following. These fillers may be used alone or in combination of two or more.
Heavy calcium carbonate with an average particle diameter of 1 to 20 μm, light calcium carbonate with an average particle diameter of 1 to 3 μm produced by a precipitation method, colloidal calcium carbonate whose surface is treated with a fatty acid or a resin acid organic substance, light calcium carbonate, etc. Calcium carbonate; fumed silica; precipitated silica; surface silicone-treated silica fine powder; silicic anhydride; hydrous silicic acid; carbon black; magnesium carbonate; diatomaceous earth; calcined clay; clay; talc; Iron; zinc oxide; activated zinc flower; Shirasu balloon, perlite, glass balloon, silica balloon, fly ash balloon, alumina balloon, zirconia balloon, carbon balloon and other inorganic hollow bodies; phenol resin balloon, epoxy resin balloon, urea resin balloon , Saran balloon, po Organic resin hollow bodies such as restyrene balloon, polymethacrylate balloon, polyvinyl alcohol balloon, styrene-acrylic resin balloon, polyacrylonitrile balloon; resin beads, wood flour, pulp, cotton chips, mica, walnut flour, rice flour flour, graphite, Examples thereof include powder fillers such as aluminum fine powder and flint powder; and fiber fillers such as glass fiber, glass filament, carbon fiber, Kevlar fiber, and polyethylene fiber.

These fillers may be used alone or in combination of two or more. Among these, it is preferable to use calcium carbonate, and it is particularly preferable to use heavy calcium carbonate and colloidal calcium carbonate in combination. By using a hollow body, a curable composition and its hardened | cured material can be reduced in weight. In addition, by using a hollow body, it is possible to improve the workability by improving the stringiness of the composition. The hollow body may be used alone or in combination with other fillers such as calcium carbonate.

  As the plasticizer, a known plasticizer can be used, but it is not necessary to use it. Phthalic acid esters such as dioctyl phthalate, dibutyl phthalate, butyl benzyl phthalate, isononyl phthalate; aliphatic carboxylic acid esters such as dioctyl adipate, diisodecyl succinate, dibutyl sebacate, butyl oleate; pentaerythritol ester, etc. Alcohol esters; phosphate esters such as trioctyl phosphate, tricresyl phosphate; epoxy plasticizers such as epoxidized soybean oil, dioctyl 4,5-epoxyhexahydrophthalate, benzyl epoxy stearate; chlorinated paraffins; 2 Polyester plasticizers such as polyesters obtained by reacting basic acids with dihydric alcohols; polyoxypropylene glycol and its derivatives, such as the hydroxyl group of polyoxypropylene glycol, sealed with alkyl ether Polyethers, poly-α-methylstyrene, polystyrene oligomers such as polystyrene, polybutadiene, butadiene-acrylonitrile copolymer, polychloroprene, polyisoprene, polybutene, hydrogenated polybutene, oligomers such as epoxidized polybutadiene, etc. Examples include molecular plasticizers. These plasticizers can be used in combination of two or more different types such as phthalate ester and epoxy plasticizer.

  In order to further improve the storage stability of the curable composition of the present invention, a small amount of a dehydrating agent can be added within a range that does not adversely affect the curability and flexibility. Specifically, alkyl orthoformate such as methyl orthoformate and ethyl orthoformate, alkyl orthoacetate such as methyl orthoacetate and ethyl orthoacetate, methyltrimethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, etc. Hydrolyzable organosilicon compounds, hydrolyzable organotitanium compounds and the like can be used. Vinyltrimethoxysilane and tetraethoxysilane are particularly preferable from the viewpoint of cost and effect. Such a dehydrating agent is particularly effective in a product in which a curing catalyst is added to a blend and filled in a moisture-proof container, which is known as a one-component blend.

In the present invention, a thixotropic agent may be used for improving the sagging property. As such a thixotropic agent, hydrogenated castor oil, fatty acid amide and the like are used in an arbitrary amount.
In the present invention, generally used antioxidants, ultraviolet absorbers, and light stabilizers can be appropriately used as the antioxidant. Hindered amine, benzotriazole, benzophenone, benzoate, cyanoacrylate, acrylate, hindered phenol, phosphorus, and sulfur compounds can be used as appropriate. In particular, the use of two or all of light stabilizers, antioxidants, and ultraviolet absorbers in combination may improve the effect as a whole by taking advantage of the respective characteristics, and thus is a preferable method. Specifically, the tertiary is particularly effective when a secondary hindered amine light stabilizer, benzotriazole ultraviolet absorber, hindered phenol and / or phosphite antioxidant is combined.

  The curable composition of the present invention can further contain and add various known additives. For example, the following known additives can be exemplified. As a surface modifier, a solvent, a modulus regulator such as a compound that generates trimethylsilanol by hydrolysis such as phenoxytrimethylsilane, a compound that cures by air such as tung oil, a compound that cures by light such as trimethylolpropane triacrylate, and a pigment Inorganic pigments such as iron oxide, chromium oxide and titanium oxide, and organic pigments such as phthalocyanine blue and phthalocyanine green can be used. The use of the pigment is effective not only for coloring but also for the purpose of improving the weather resistance. It is optional to add a known flame retardant or fungicide. It is also possible to add a matting agent used in paint applications.

The curable composition of the present invention can give a cured product by crosslinking a silicon group-containing oxyalkylene polymer by hydrolysis and crosslinking reaction of hydrolyzable silicon groups by moisture in the air at room temperature.
In addition, the curing method of the curable composition of the present invention is not particularly limited, and the curable composition of the present invention and other desired components are mixed and sealed and stored. A curing method for a one-component curing composition for curing the composition, a curing method for a two-component curing composition in which the curable composition of the present invention and other desired components are mixed in use and cured appropriately It is preferable to do this.
The curable composition of the present invention has high curability and storage stability, and can form a cured product having good mechanical properties. The curable composition of the present invention is useful as a coating / sealing curable composition as an architectural sealant, waterproof material, adhesive, or coating agent, and particularly useful as an architectural sealant or adhesive.
As a preferred use mode of the architectural sealant or adhesive comprising the curable composition of the present invention, the curable composition of the present invention and other desired components are stored in a sealed state, and in use, they are stored in the air. Examples thereof include a one-component curable adhesive that cures an adhesive with moisture, and a two-component curable adhesive that mixes and cures the curable composition of the present invention and other components as desired.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to these examples.
In addition, the mass average molecular weight (Mw), the number average molecular weight (Mn), and the molecular weight distribution (Mw / Mn) of various polymers in the following examples and comparative examples are measured using gel permeation chromatography (GPC). It is the value. Specifically, a column in which two Multipore HxLs (manufactured by Tosoh Corporation) were connected in series was used as a GPC column, tetrahydrofuran was used for the mobile phase, and the temperature was measured at 40 ° C. Moreover, the value of Mw, Mn, and Mw / Mn was calculated | required as a polystyrene conversion molecular weight using the calibration curve created using the polystyrene standard sample (Polymer Laboratories PS-2) with known molecular weight.

(Production example)
The oxyalkylene polymer (A) having a reactive silicon group and the (meth) acrylic polymer (B) having a reactive silicon group were produced as follows. In the following production examples, the synthesis reaction was performed using a pressure-resistant reaction vessel equipped with a nitrogen introduction tube and a stirring device and capable of adjusting the internal temperature.

(Production Example 1: Production of oxyalkylene polymer (A1) having reactive silicon group)
In the presence of a zinc hexacyanocobaltate-glyme complex catalyst, polyoxypropylene diol (Mn 1000) is subjected to ring-opening polymerization of propylene oxide to produce polyoxypropylene diol (Mn 16000, hydroxyl value 7.7) (polymer (P-1)). Got. 3000 g of the polymer (P-1) was placed in a pressure resistant reactor (internal volume 5 L), and dehydrated under reduced pressure while maintaining the internal temperature at 110 ° C. Next, the atmosphere in the reactor was replaced with nitrogen gas, and while maintaining the internal temperature at 50 ° C., 86 of 3-isocyanatopropyltrimethoxysilane (purity 95%) was adjusted so that NCO / OH was 0.97. .1 g was charged. Subsequently, the internal temperature is maintained at 80 ° C. for 8 hours, and the polymer (P-1) and 3-isocyanatopropyltrimethoxysilane are subjected to a urethanation reaction, whereby an oxyalkylene polymer having a trimethoxysilyl group at the terminal ( A1) was obtained.
The viscosity of the obtained oxyalkylene polymer (A1) was 20.0 Pa · s (25 ° C.), Mn was 16100, and Mw / Mn was 1.38.

(Production Example 2: Production of oxyalkylene polymer (A2) having reactive silicon group)
Using 1000 g of polyoxypropylene diol (Mn 3200) as an initiator, 4000 g of propylene oxide was polymerized in the presence of 1.6 g of zinc hexacyanocobaltate-glyme complex catalyst. Add 1.05 equivalents of a methanol solution of sodium methoxide to the hydroxyl group of the resulting polyoxypropylene diol, and distill off the methanol under heating and reduced pressure to convert the terminal hydroxyl group of the polyoxyalkylene diol to sodium methoxide. did. Next, 1.20 equivalent of allyl chloride was added and reacted. After the reaction, unreacted allyl chloride was removed under reduced pressure, and further purified to remove by-produced salts to obtain an allyl group-terminated oxyalkylene polymer. To 1000 g of this polymer, 17.6 g of 3-mercaptopropyltrimethoxysilane and 2.5 g of 2,2′azobis (2-methylbutyronitrile) were added, and the reaction was performed by heating at 70 ° C. for 12 hours. An oxyalkylene polymer (A2-1) having a trimethoxysilyl group at the end of the polymer was obtained. The number average molecular weight (Mn) of this polymer was 16000, and Mw / Mn was 1.2.

Further, 100 g of polyoxypropylene triol (Mn 1500) was used as an initiator, and 1233 g of propylene oxide was polymerized in the presence of 0.16 g of a zinc hexacyanocobaltate-glyme complex catalyst. Using the obtained polyoxyalkylene triol, an allyl group-terminated oxyalkylene polymer was obtained in the same manner as described above. To 1000 g of this polymer, 21.1 g of 3-mercaptopropyltrimethoxysilane and 3.0 g of 2,2′azobis (2-methylbutyronitrile) were added and reacted by heating at 70 ° C. for 12 hours. An oxyalkylene polymer (A2-2) having a trimethoxysilyl group at the end of the polymer was obtained. The number average molecular weight (Mn) of this polymer was 20000, and Mw / Mn was 1.3.
The above polymers (A2-1) and (A2-2) are mixed at a mass ratio of 7: 3 to obtain an oxyalkylene polymer (A2) having a reactive silicon group with an average functional group number of 2.3. It was. The number average molecular weight of this polymer was 17,200.

(Production Example 3: Production of oxyalkylene polymer (A3) having a reactive silicon group)
Propylene oxide was reacted with polyoxypropylene triol (Mn1000) as an initiator in the presence of a zinc hexacyanocobaltate-glyme complex catalyst to obtain a polyoxypropylene triol having an Mn of 17000 and Mw / Mn of 1.4. . Using this polyoxypropylene triol, an allyl group-terminated polyoxyalkylene polymer having a viscosity of 7.0 Pa · s (25 ° C.) was obtained in the same manner as in Production Example 2.
Furthermore, this polymer was reacted with methyldimethoxysilane in the presence of a platinum catalyst to obtain an oxyalkylene polymer (A3) having a methyldimethoxysilyl group at the terminal.
The viscosity of the obtained oxyalkylene polymer (A3) was 9.0 Pa · s (25 ° C.), Mn was 17000, and Mw / Mn was 1.4.

(Production Example 4: Production of (meth) acrylic polymer (B1) having a reactive silicon group)
140 g of oxyalkylene polymer (A1) was put into a pressure-resistant reactor equipped with a stirrer, and the temperature was raised to about 67 ° C. While maintaining the internal temperature of the reaction vessel at about 67 ° C. and stirring under a nitrogen atmosphere, 72 g of methyl methacrylate, 6.5 g of acrylate-n-butyl, 29.0 g of methacrylic acid-n-butyl, 3-methacryloyloxypropyltri A predetermined amount of a monomer selected from 15.0 g of ethoxysilane and 14.0 g of normal dodecyl mercaptan, and 2,2′-azobis (2,4-dimethylvaleronitrile) (trade name “V65” manufactured by Wako Pure Chemical Industries, Ltd.) A (meth) acrylic polymer containing a reactive silicon group containing an oxyalkylene polymer (A1) is polymerized by adding 2.5 g of the mixed solution dropwise to the oxyalkylene polymer (A1) over 8 hours. (B1) was obtained. Moreover, after dissolving the obtained polymer in hexane, it centrifuged, extracted, and measured the number average molecular weight (Mn) of the (meth) acrylic polymer (B1). The number average molecular weight (Mn) of this (meth) acrylic polymer (B1) was 4000.

(Production Example 5: Production of (meth) acrylic polymer (B2) having a reactive silicon group)
140 g of the oxyalkylene polymer (A1) having a reactive silicon group was put in a pressure-resistant reactor equipped with a stirrer, and the temperature was raised to about 67 ° C. While maintaining the reaction vessel internal temperature at about 67 ° C. and stirring in a nitrogen atmosphere, methyl methacrylate 72 g, butyl acrylate 6.5 g, butyl methacrylate 29.0 g, 3-methacryloyloxypropyltrimethoxysilane 12.7 g, And a predetermined amount of a monomer selected from 14.0 g of normal dodecyl mercaptan and 2.5 g of 2,2′-azobis (2,4-dimethylvaleronitrile) (trade name “V65” manufactured by Wako Pure Chemical Industries, Ltd.) Is dropped into the oxyalkylene polymer (A1) having a reactive silicon group over 8 hours to perform polymerization, and has a reactive silicon group including the oxyalkylene polymer (A1) having a reactive silicon group. A (meth) acrylic polymer (B2) was obtained. Moreover, after dissolving the obtained polymer in hexane, it centrifuges and extracts, The number average molecular weight (Mn) and molecular weight distribution (Mw / Mn) of (meth) acrylic polymer (B2) are obtained. It was measured. The number average molecular weight (Mn) of this (meth) acrylic polymer (B2) was 4000.

(Production Example 6: Production of (meth) acrylic polymer (B3) having a reactive silicon group)
Except that the oxyalkylene polymer (A1) was changed to the oxyalkylene polymer (A2), the same operation as in Production Example 5 was performed, and the reactive silicon group containing the oxyalkylene polymer (A2) having a reactive silicon group was changed. A (meth) acrylic polymer (B3) was obtained.

(Production Example 7: Production of (meth) acrylic polymer (B4) having a reactive silicon group)
Except that the oxyalkylene polymer (A1) was changed to the oxyalkylene polymer (A3), the same operation as in Production Example 4 was performed, and the reactive silicon group containing the oxyalkylene polymer (A3) having a reactive silicon group was changed. A (meth) acrylic polymer (B4) was obtained.

(Production Example 8: Production of (meth) acrylic polymer (B5) having a reactive silicon group)
140 g of oxyalkylene polymer (A1) was put into a pressure-resistant reactor equipped with a stirrer, and the temperature was raised to about 67 ° C. While maintaining the internal temperature of the reaction vessel at about 67 ° C. and stirring in a nitrogen atmosphere, 72 g of methyl methacrylate, 6.5 g of acrylic acid-n-butyl, 29.0 g of methacrylate-n-butyl, 3-methacryloyloxypropylmethyl A predetermined amount of a monomer selected from 12.0 g of dimethoxysilane and 14.0 g of normal dodecyl mercaptan, and 2,2′-azobis (2,4-dimethylvaleronitrile) (trade name “V65” manufactured by Wako Pure Chemical Industries, Ltd.) 2.5 g of the mixed solution is dropped into the oxyalkylene polymer (A1) over 8 hours to perform polymerization, and an acrylic polymer (B5) containing a reactive silicon group containing the oxyalkylene polymer (A1). ) Moreover, after dissolving the obtained polymer in hexane, it centrifuged, extracted, and measured the number average molecular weight (Mn) of the (meth) acrylic polymer (B5). The number average molecular weight (Mn) of this (meth) acrylic polymer (B5) was 4000.

(Production Example 9: Production of (meth) acrylic polymer (B6) having a reactive silicon group)
Except that the oxyalkylene polymer (A1) was changed to the oxyalkylene polymer (A3), the same operation as in Production Example 8 was performed, and the reactive silicon group containing the oxyalkylene polymer (A3) having a reactive silicon group was changed. A (meth) acrylic polymer (B6) was obtained.

Example 1
Collagen calcium carbonate (commodity) dried at 120 degrees for 12 hours with respect to 100 parts by mass of the (meth) acrylic polymer (B1) containing a reactive silicon group containing the oxyalkylene polymer (A1) obtained in Production Example 4. Name “Shiraka Hana CCR” (manufactured by Shiraishi Calcium Co., Ltd.) 50 parts by mass, heavy calcium carbonate (trade name “NS-400”, manufactured by Toshin Kasei Co., Ltd.) dried at 120 ° C. for 12 hours and planetary stirring The mixture was stirred and mixed using a vessel (Kurabo). After the temperature of the obtained mixture is lowered to room temperature, 5 parts by mass of vinyltrimethoxysilane (trade name “KBM-1003”, manufactured by Shin-Etsu Chemical Co., Ltd.) is added as a dehydrating agent, and the mixture is stirred and mixed. N-2 (aminoethyl) 3-aminopropyltrimethoxysilane (trade name “KBM-603”, manufactured by Shin-Etsu Chemical Co., Ltd.) 3 parts by mass, and 3-glycidoxypropyltrimethoxysilane (trade name “KBM-403”) “Shin-Etsu Chemical Co., Ltd.) 1 part by mass was added and stirred and mixed. 2 parts by mass of 918 (manufactured by Sansha Co., Ltd.) was added and mixed uniformly to prepare a curable composition.

(Examples 2-6 and Comparative Examples 1-4)
A curable composition was prepared in the same manner as in Example 1 except that the compositions shown in Tables 1 and 2 were used.

(Evaluation of curable composition)
(Surface tack test of curable composition)
A surface tack test was performed on each of Examples 1 to 6 and Comparative Examples 1 to 4. The surface tack test was performed according to JIS A1439. Specifically, when the surface of the cured product obtained by curing the prepared composition was touched with a finger, the time when the cured product did not adhere to the finger was measured as a tack-free time (minutes).

(Weather resistance test)
A mixture of an oxyalkylene polymer, a (meth) acrylic polymer, a filler, a silane coupling agent, and a curing catalyst prepared in Examples 1 to 6 in Table 1 and Comparative Examples 1 to 4 in Table 2 was used. The mixture was lightly stirred with a spatula and then kneaded using a planetary stirrer (manufactured by Kurashiki Boseki Co., Ltd.) to obtain a curable composition. Next, the curable composition was applied to a thickness of 5.0 mm on the surface of a siding board (product name: HONBA, manufactured by Asahi Glass Co., Ltd.) measuring 5 cm in length and 5 cm in width. This was cured for 1 week under conditions of a temperature of 23 ° C. and a humidity of 60% to obtain a weather resistance test sample. The sample was evaluated for weather resistance using a sunshine weatherometer, which is a weather resistance acceleration tester. The surface condition of each sample when the test time was 500, 1000, and 1500 hours was visually observed, and the surface of the weather resistance test sample started to fade (whitening), and the surface color completely faded. The sample was marked with ×, and the sample surface color that was not changed from the state before the start of the test was marked with ○.

  As shown in Table 1, the curable compositions of Examples 1 to 5 were excellent in weather resistance and fast in tack-free time (curing speed). On the other hand, as shown in Table 2, Comparative Example 3 using only the oxyalkylene polymer having a reactive silicon group has a slow tack-free time and has a problem in weather resistance. The tack-free time was fast, but there was a problem in weather resistance. Moreover, the rise of hardness was slow. Further, Comparative Example 4 using an oxyalkylene polymer having a reactive silicon group containing only a methyldimethoxysilyl group and a (meth) acrylic polymer was excellent in weather resistance, but had a problem that tack-free time was slow. It was.

The present invention can be suitably used as a curable composition having good weather resistance and a high curing rate.

Claims (9)

Contains an oxyalkylene polymer (A) having a reactive silicon group represented by the following formula (2) and a (meth) acrylic polymer (B) having a reactive silicon group represented by the following formula (2) In the reactive silicon group of the oxyalkylene polymer (A) having a reactive silicon group, the reactive silicon group (S1) represented by the formula (1) is contained in an amount of 10 to 100%. The (meth) acrylic polymer (B) having a reactive silicon group is a polymer containing a (meth) acrylic acid alkyl ester monomer unit as an essential component, The monomer unit is a (meth) acrylic acid alkyl ester monomer unit having 1 to 2 carbon atoms in the alkyl group and a (meth) acrylic acid alkyl ester monomer unit having 3 to 6 carbon atoms in the alkyl group. Do Ri, reaction An unsaturated group-containing monomer having a functional silicon group, a (meth) acrylic acid alkyl ester monomer having 1 to 2 carbon atoms in the alkyl group, and a (meth) acryl having 3 to 6 carbon atoms in the alkyl group an acid alkyl ester by polymerizing a monomer comprising a monomer having a reactive silicon group that obtained (meth) acrylic polymer, an oxyalkylene polymer having a reactive silicon group (a) and a reactive silicon Curing characterized by containing 10 to 70 parts by mass of (meth) acrylic polymer (B) having a reactive silicon group with respect to 100 parts by mass of the total amount of (meth) acrylic polymer (B) having a group Sex composition.
-Si (OR) ₃ (1)
(In the formula, R is independently an organic group having 1 to 6 carbon atoms.)
-SiX ¹ _a R ¹ _3-a (2)
(In the formula, R ¹ is an optionally substituted monovalent organic group having 1 to 20 carbon atoms, X ¹ is a hydroxyl group or a hydrolyzable group, and a is an integer of 1 to 3. there. However, may be different or a plurality of R ¹ is each independently when R ¹ there are a plurality, a plurality of X ¹ may be the same or different when X ¹ is more present.) In the monomer polymerized to the (meth) acrylic polymer (B) having a reactive silicon group, the alkyl group having 1 to 2 carbon atoms (meth) acrylic acid alkyl ester monomer / alkyl group carbon 2. The curable composition according to claim 1 , wherein the mass ratio of the (meth) acrylic acid alkyl ester monomer having 3 to 6 is 97/3 to 40/60. In the monomer polymerized to the (meth) acrylic polymer (B) having a reactive silicon group, the alkyl group having 1 to 2 carbon atoms (meth) acrylic acid alkyl ester monomer / alkyl group carbon The curable composition according to claim 1 or 2, wherein the mass ratio of the (meth) acrylic acid alkyl ester monomer having 3 to 6 is 90/10 to 45/55. The content ratio of the reactive silicon group (S1) in which R in the reactive silicon group of the oxyalkylene polymer (A) having the reactive silicon group is an alkyl group having 1 to 6 carbon atoms is 50. It is -100%, The curable composition in any one of Claims 1-3. The content ratio of the trimethoxysilyl group in the reactive silicon group of the oxyalkylene polymer (A) which has the said reactive silicon group is 50 to 100%, The curable composition in any one of Claims 1-3 . The curable composition according to any one of claims 1 to 5, wherein the reactive silicon group (S1) is a reactive silicon group represented by the following formula (3).
-Si (OCH ₃ ) ₃ (3) The oxyalkylene polymer (A) having a reactive silicon group is a polymer obtained by subjecting a polymer having a polyoxyalkylene chain and a hydroxyl group and a compound represented by the formula (4) to a urethanization reaction. It is a coalescence (A1), The curable composition in any one of Claims 1-6.
X ¹ _a R ¹ _3-a Si—R ² —NCO (4)
^(Wherein, X 1, ^{R 1} is .a is the same as ^X 1, ^{R 1} in the formula (1) is an integer of 1-3. However, a plurality of ^{R 1 when R 1} there are a plurality may be the same or different from each other, a plurality of X ¹ may be the same or different when X ¹ is more present.) The reactive silicon group (S2) represented by the said Formula (1) is included in the reactive silicon group of the said (meth) acrylic polymer (B) in any one of Claims 1-7. Curable composition. The curable composition according to any one of claims 1 to 8, wherein the reactive silicon group (S2) of the (meth) acrylic polymer (B) is a reactive silicon group represented by the following formula (3). .
-Si (OCH ₃ ) ₃ (3)