JP5564997B2 - Curable composition and method for producing the same - Google Patents

Description

  The present invention relates to a curable composition containing a polymer having a reactive silicon group and curable at room temperature by moisture in the air.

  The polymer having a reactive silicon group is crosslinked by the hydrolysis and condensation reaction of the reactive silicon group to form a siloxane bond. Therefore, it can be cured by moisture in the air at room temperature, and becomes a cured product having rubber elasticity after curing. Since the obtained cured product has excellent characteristics for various adherends, it is widely used as a base material for sealing materials, adhesives, coatings or sealing compositions.

In general, a curable composition used for a sealing material, an adhesive or the like is preferably a cured product that is flexible and stretches well. For this purpose, a plasticizer is blended in the curable composition.
As the plasticizer, aromatic carboxylic acid esters, aliphatic carboxylic acid esters, glycol esters, phosphate esters, epoxy plasticizers, chlorinated paraffins and the like are generally used.
It is also known to use an acrylic polymer or a polyether polymer as a plasticizer (Patent Document 1).
However, since these plasticizers have migratory properties, they easily flow out of the cured product, and there are problems such as contamination around the sealing portion, adverse effects on adhesion, contamination on the surface coating, and poor adhesion.

  On the other hand, it has been proposed to use a low molecular weight polymer having a reactive silicon group as a plasticizer having low migration. For example, in Patent Document 2, a high molecular weight polymer (I) having a molecular weight of 8,000 to 50,000 having an average of 1 to 1.5 reactive silicon groups per molecule and an average of 0.5 to 1 per molecule. A curable composition is described in combination with a low molecular weight polymer (II) having 300 reactive molecular groups and a molecular weight of 300 to 8,000. In Patent Document 2, as examples of the high molecular weight polymer (I), polymers A to C having a molecular weight of 18,000 having an average of 1.2 to 1.8 methyldimethoxysilylpropyl groups per molecule are described. Has been.

Japanese Patent Laid-Open No. 10-60253 JP-A-9-95619

By the way, in order to develop excellent elongation properties, it is preferable that the high molecular weight polymer having a reactive silicon group has a higher molecular weight than the conventional high molecular weight polymer. However, the high molecular weight polymer has a high viscosity, and there is a problem that workability is impaired when the cured product is used as a sealing material or an adhesive. In order to obtain a curable composition for a sealing material or an adhesive by using a high molecular weight polymer, a larger amount of plasticizer is required. However, since problems such as contamination around the sealing portion, adverse effects on adhesiveness, contamination on the surface coating and lowering of adhesiveness appear remarkably, improvement has been particularly demanded.
In addition, according to the knowledge of the present inventors, even in a method using a low molecular weight polymer having a reactive silicon group as a plasticizer having low migration, the cured product has flexibility, elongation, durability, or coating contamination. It turned out to be inferior and needed to be improved.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a curable composition in which the cured product has good flexibility, elongation and durability and is free from coating film contamination.

The present invention is the following [1] to [ 10 ].
[1] A polymer obtained by introducing a reactive silicon group represented by the following formula (1) into a linear precursor polymer (A ′) capable of introducing reactive silicon groups at both ends. there are a number average molecular weight of 20,000 or more, 40,000 Ri der hereinafter polymer molecular weight distribution Ru der 1.0 to 1.2 (a), and a linear, reactive silicon group at one end Is a polymer obtained by introducing a reactive silicon group represented by the following formula (1) into a precursor polymer (B ′) into which a number average molecular weight is 3,000 or more and 20,000 or less And the ratio of the terminal group substituted with the reactive silicon group in the terminal group capable of introducing the reactive silicon group of the precursor polymer (B ′) is 60 to 100 mol% (B And a mass ratio (A / B) of the content of the polymer (A) and the content of the polymer (B) is 95/5 to 5/95. Composition.
-SiX ¹ ₂ R ¹ (1)
[Wherein, R ¹ represents an optionally substituted monovalent organic group having 1 to 20 carbon atoms (excluding a hydrolyzable group), and X ¹ represents a hydroxyl group or a hydrolyzable group. . Two X ¹ may be the same or different from each other. ]

[2] The curable composition according to [1] , which does not contain the following polymer (Z) .
Polymer (Z): A polymer having a branched polyoxyalkylene chain and having a reactive silicon group.
[3] The curable composition according to [1] or [2], wherein the polymer (B) has a molecular weight distribution (Mw / Mn) of 1.0 to 1.8.
[4] In the polymer (A), the ratio of terminal groups substituted with the reactive silicon group among the terminal groups into which the reactive silicon group of the precursor polymer (A ′) can be introduced is 70 to 100. Curable composition of [1]-[3] which is mol%.
[5] The precursor polymer (A ′) is a precursor polymer (A′1) produced by ring-opening addition polymerization of alkylene oxide to an initiator having two active hydrogens in the presence of a catalyst. [1]-[4] curable composition.
[6] Hydroxyl group of a polymer in which the precursor polymer (A ′) is produced by ring-opening addition polymerization of alkylene oxide to an initiator having two active hydrogens in the presence of a catalyst. Of [1] to [4], which is a precursor polymer (A′2) produced by a method in which is alcoholated to -OM (M is an alkali metal) and then reacted with an unsaturated group-containing halogenated hydrocarbon Curable composition.

[7] The precursor polymer (B ′) is a precursor polymer (B′1) produced by ring-opening addition polymerization of an alkylene oxide to an initiator having one active hydrogen in the presence of a catalyst. [1]-[6] curable composition.
[8] A hydroxyl group of a polymer in which the precursor polymer (B ′) is produced by ring-opening addition polymerization of alkylene oxide to an initiator having one active hydrogen in the presence of a catalyst, and one end of which is a hydroxyl group Of [1] to [6], which is a precursor polymer (B′2) produced by a method in which is alcoholated to -OM (M is an alkali metal) and then reacted with an unsaturated group-containing halogenated hydrocarbon Curable composition.
[9] The curable composition of [1] to [8], which is for a sealing material or an adhesive.
[10] An initiator having two active hydrogens is subjected to a step of addition polymerization of an alkylene oxide monomer using a zinc hexacyanocobaltate t-butanol complex catalyst to form a linear polyoxyalkylene chain. And a step of obtaining a precursor polymer (A ′) capable of introducing a reactive silicon group at both ends, and a reactive silicon group represented by the following formula (1) in the precursor polymer (A ′): Introducing, a step of obtaining a polymer (A) having a number average molecular weight of 20,000 or more and 40,000 or less, and a step of addition polymerization of an alkylene oxide monomer to an initiator having one active hydrogen, A step of obtaining a precursor polymer (B ′) that is linear, has a polyoxyalkylene chain and can introduce a reactive silicon group at one end, and the precursor polymer (B ′) has the following formula (1) ), The number average molecular weight is 3, The ratio of the terminal group substituted with the reactive silicon group in the terminal group capable of introducing the reactive silicon group of the precursor polymer (B ′) is from 60 to 100 mol%. And the mass ratio (A / B) of the content of the polymer (A) and the content of the polymer (B) is 95/5 to 5/95. The manufacturing method of a curable composition which has the process to mix.
-SiX ¹ ₂ R ¹ (1)
[Wherein, R ¹ represents an optionally substituted monovalent organic group having 1 to 20 carbon atoms (excluding a hydrolyzable group), and X ¹ represents a hydroxyl group or a hydrolyzable group. . Two X ¹ may be the same or different from each other. ]

  According to the curable composition of the present invention, it is possible to obtain a cured product having good flexibility, elongation and durability in the cured product and having no coating film contamination.

The mass average molecular weight (Mw, hereinafter also referred to as “Mw”) and the number average molecular weight (Mn, hereinafter also referred to as “Mn”) in the present specification are molecular weights in terms of polystyrene measured by gel permeation chromatography (GPC). . The molecular weight distribution in the present specification (hereinafter also referred to as “Mw / Mn”) is a value calculated from Mw and Mn measured by the above-described method, and is a mass average molecular weight (Mw) with respect to the number average molecular weight (Mn). The ratio (Mw / Mn).
In the present specification, the molecular weight converted from the hydroxyl value is referred to as “hydroxyl converted molecular weight MW (OH)”. That is, the relationship between the hydroxyl value (the amount of hydroxyl group contained in the polymer (unit: mg KOH / g)) and the hydroxyl equivalent molecular weight MW (OH) is represented by the following formula.
Hydroxyl equivalent molecular weight MW (OH) = number of hydroxyl groups per molecule of the compound used as the initiator of the polymer × 56,100 / hydroxyl value The hydroxyl value in the present specification is a method based on JIS K1557-1. It is a measured value.
The viscosity value (unit: mPa · s or Pa · s) in this specification is determined using an E-type viscometer at 25 ° C. 4 rotor (cone rotor: 3 ° × R14), or No. It is a value measured using one rotor (cone rotor: 1 ° 34 ′ × R24).

<Polymer (A)>
The polymer (A) used in the present invention has a reactive silicon group represented by the above formula (1).
In Formula (1), R ¹ represents a monovalent organic group having 1 to 20 carbon atoms (excluding a hydrolyzable group) which may have a substituent. R ¹ is preferably a hydrocarbon group having 8 or less carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, a cyclohexyl group, and a phenyl group. A methyl group and a phenyl group are more preferable, and a methyl group is particularly preferable.

In the formula (1), X ¹ represents a hydroxyl group or a hydrolyzable group. Two X ¹ existing in one molecule may be the same as or different from each other.
The hydrolyzable group refers to a substituent that is directly bonded to a silicon atom and can form 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, and an alkenyloxy 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. More specifically, X ¹ is particularly preferably a methoxy group or an ethoxy group.

The polymer (A) is a polymer obtained by introducing reactive silicon groups into a precursor polymer (A ′) that is linear and capable of introducing reactive silicon groups at both ends. That is, it is a polymer in which part or all of both terminal groups of the linear precursor polymer (A ′) are substituted with reactive silicon groups.
When there is a reactive silicon group at the terminal of the polymer (A), the elongation property, internal curability and surface curability of the cured product are likely to be good.

The polymer (A) is a compound in which both terminal groups of the precursor polymer (A ′) are reactive and has both a group that reacts with the terminal group and a reactive silicon group (hereinafter referred to as “silylating agent”). And a precursor polymer (A ′) can be reacted to introduce a reactive silicon group.
It is preferable that both terminal groups of the precursor polymer (A ′) are each independently a monovalent group (hereinafter referred to as an unsaturated group) or a hydroxyl group containing an unsaturated double bond.

The polymer (A) is preferably obtained through a step of addition polymerization of an alkylene oxide monomer and / or a (meth) acrylic acid alkyl ester monomer to an initiator having two active hydrogens.
That is, it is preferable that the repeating unit in the precursor polymer (A ′) and the polymer (A) includes an alkylene oxide monomer unit and / or a (meth) acrylic acid alkyl ester monomer unit. It is preferable to have at least a chain of alkylene oxide monomer units, that is, a polyoxyalkylene chain.
When the polymer (A) has a polyoxyalkylene chain, there are advantages such as low temperature dependence, easy flexibility of the cured product, and excellent price.

Alternatively, as a part or all of the polymer (A), the repeating unit in the precursor polymer (A ′) and the polymer (A) includes a (meth) acrylic acid alkyl ester monomer unit, and a polyoxyalkylene chain. You may use the acrylic polymer which does not have. Such a polymer contributes to improving the mechanical strength of the cured product and improving the weather resistance of the curable composition and the cured product.
In this specification, the (meth) acrylic acid alkyl ester monomer unit means a repeating unit derived from a (meth) acrylic acid alkyl ester. (Meth) acrylic acid alkyl ester means acrylic acid alkyl ester, methacrylic acid alkyl ester or a mixture of both.

As the precursor polymer (A ′), a linear precursor polymer (A′1) having a polyoxyalkylene chain and both ends being hydroxyl groups; or having a polyoxyalkylene chain and both ends being A linear precursor polymer (A′2) which is an unsaturated group is preferred.
The precursor polymer (A′1) can be produced by subjecting an alkylene oxide to ring-opening addition polymerization to an initiator having two active hydrogens in the presence of a catalyst.
As the initiator, a compound having two hydroxyl groups is preferable. Specific examples include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, 1,4-butanediol, and 1,6-hexanediol. Of these, propylene glycol and dipropylene glycol are more preferable. Further, polyoxyalkylene diol having a hydroxyl equivalent molecular weight MW (OH) of 190 to 20,000 obtained by ring-opening addition polymerization of alkylene oxide to a compound having two hydroxyl groups can be used as an initiator. An initiator may be used individually by 1 type and may use 2 or more types together.

The alkylene oxide used for the synthesis of the precursor polymer (A′1) or the initiator preferably has 2 to 20 carbon atoms, and specific examples include propylene oxide, butylene oxide, ethylene oxide and the like. Propylene oxide is particularly preferred. An alkylene oxide may be used individually by 1 type, and may use 2 or more types together. When the polyoxyalkylene chain is composed of two or more oxyalkylene monomer units, the arrangement of the monomer units may be block or random.
Examples of the catalyst include an alkali metal catalyst, a double metal cyanide complex catalyst, and a metal porphyrin. In particular, a double metal cyanide complex catalyst is preferable because the molecular weight distribution of the polymer (A) tends to be small.

In the presence of a catalyst, the linear precursor polymer (A′2) having a polyoxyalkylene chain and unsaturated groups at both ends opens an alkylene oxide to an initiator having two active hydrogens. A polymer produced by cycloaddition polymerization and having hydroxyl groups at both ends, that is, the hydroxyl group (—OH) of the precursor polymer (A′1) is alcoholated to -OM (M is an alkali metal), and then allyl chloride And a method of reacting with an unsaturated group-containing halogenated hydrocarbon such as methallyl chloride. This method is general and preferable in terms of easy availability of raw materials and high yield.
Alternatively, a compound having a functional group capable of reacting with a hydroxyl group and an unsaturated group is reacted with the precursor polymer (A′1) to introduce an unsaturated group via an ester bond, a urethane bond, a carbonate bond, or the like. can get.

As a method for obtaining the polymer (A) by introducing a reactive silicon group into the terminal unsaturated group of the precursor polymer (A′2), a known method can be used. For example, the following method [1] or [2] can be used.
[1] A method of reacting a terminal unsaturated group with a silicon hydride compound represented by the following formula (2) in the presence of a catalyst. However, X ¹ and R ¹ in the formula (2) are the same as in the above formula (1).
HSiX ¹ ₂ R ¹ (2)
[2] A method of reacting a terminal unsaturated group with a mercapto group of a silicon compound represented by the following formula (3).
W ¹ R ² —SiX ¹ ₂ R ¹ (3)
X ¹ and R ¹ in the formula (3) are the same as those in the above formula (1). R ² is a divalent organic group, and W ¹ is a mercapto group.

A known method is used to obtain a polymer (A) by introducing a reactive silicon group into the terminal hydroxyl group of the precursor polymer (A′1) without going through the precursor polymer (A′2). Can do. For example, the following method [3] or [4] can be used.
[3] A method in which a terminal hydroxyl group and an isocyanate silane compound (U) represented by the following formula (4) are urethanated. This reaction may be performed in the presence of a urethanization catalyst.
^{_{NCO- (CH 2) n -SiX 1}} 2 R 1 ... (4)
X ¹ and R ¹ in the formula (4) are the same as in the above formula (1). n is an integer of 1 to 8, preferably 1 to 3.
Preferred examples of the isocyanate silane compound (U) include 1-isocyanate methyldimethoxymethylsilane, 1-isocyanatemethyldiethoxyethylsilane, 1-isocyanatepropyldimethoxymethylsilane, 3-isocyanatepropyldimethoxymethylsilane, 3-isocyanatepropyldiethoxy. Examples include ethylsilane.
The urethanization catalyst to be used is not specifically limited, A well-known urethanization catalyst can be used suitably. For example, organic tin compounds (dibutyltin dilaurate, dioctyltin dilaurate, etc.), metal catalysts such as bismuth compounds, and base catalysts such as organic amines are used. The reaction temperature is preferably 20 to 200 ° C, particularly preferably 50 to 150 ° C. The urethanization reaction is preferably performed in an inert gas (nitrogen gas is preferred) atmosphere.

[4] A group represented by W ² of a silicon compound represented by the following formula (5) after reacting a terminal hydroxyl group with a polyisocyanate compound such as tolylene diisocyanate to convert the terminal to an isocyanate group. How to react.
_{^{W 2 R 3 -SiX 1 2 R}} 1 ... (5)
X ¹ and R ¹ in the formula (5) are the same as in the above formula (1). R ³ is a divalent organic group, and W ² is an active hydrogen-containing group selected from a hydroxyl group, a carboxyl group, a mercapto group, and an amino group (primary or secondary).

In the polymer (A), the proportion of the terminal group of the precursor polymer (A ′) substituted with the reactive silicon group among the terminal groups capable of introducing the reactive silicon group (hereinafter referred to as “silylation rate”) Is also preferably 70 to 100 mol%.
The silylation rate in the polymer (A) can be controlled by the molar ratio between the terminal group and the reactive silicon group when the terminal group of the precursor polymer (A ′) is reacted with the silylating agent.
The value of the silylation rate in this specification can be measured by NMR analysis. Or, since the reaction rate between the precursor polymer (A ′) produced using methallyl chloride and the silylating agent can be regarded as almost 100%, silylation with respect to the charged amount of the precursor polymer (A ′). You may use the value calculated from the preparation amount of an agent. In the reaction between the precursor polymer (A ′) produced using allyl chloride and the silylating agent, a side reaction occurs. Approximately 10 mol% of the allyl group of the precursor polymer (A ′) produced using allyl chloride is isomerized and not silylated, so that 100% silylation is difficult. However, in a silylation with a silylation rate of up to 90%, the reaction rate can be regarded as almost 100%. Therefore, when the silylation rate of the polymer (A) to be obtained by the reaction between the precursor polymer (A ′) produced using allyl chloride and the silylating agent is less than 90%, the polymer ( As the value of the silylation rate in A), a value calculated from the charged amount of the silylating agent with respect to the charged amount of the precursor polymer (A ′) may be used.
When two or more kinds of polymers corresponding to the polymer (A) are mixed and used, the silylation rate in the mixture after mixing may be within the above range, and one of the polymers (A) before mixing. A part having a silylation rate of less than 70% may be used.
The same applies to the polymer (B) described later.

In the curable composition of the present invention, the higher the amount of the polymer (B), the lower the viscosity. On the other hand, when the polymer (B) is blended with the polymer (A) and cured, the polymers (A) are cross-linked and a part of the polymer (A) reacts with the polymer (B). Since the polymer (B) has a reactive silicon group only at one end, the polymer (A) reacts with the polymer (B) to inhibit the crosslinking of the polymer (A). Therefore, when there are too many compounding quantities of a polymer (B), it will be hardened | cured and may become uncured.
That is, in order to make the curable composition have a lower viscosity and not to cause poor curing, it is advantageous that the amount of the polymer (B) is large and the silylation rate of the polymer (A) is high. The higher the silylation rate of the polymer (A), the more the polymer (B) is blended, the more difficult the crosslinking is due to the quantitative ratio, and the harder it becomes uncured.
Therefore, the silylation rate of the polymer (A) needs to be in a range where good curability can be obtained in the curable composition in which the polymer (B) is blended, and the higher silylation rate is. The amount of the polymer (B) added can be increased. Since the one where there is much blending quantity of a polymer (B) becomes lower viscosity, workability | operativity becomes better as a curable composition for sealing materials and adhesives.

When the precursor polymer (A ′) has a hydroxyl group as a terminal group into which a reactive silicon group can be introduced, the ratio of the terminal group substituted with the reactive silicon group (silylation rate) among all the hydroxyl groups is: 70 mol% or more is preferable, and 75 mol% or more is more preferable. If it is less than 70 mol%, it becomes a gel-like material that does not harden depending on the formulation, and there is a possibility that a sealing material and an adhesive cannot be produced. The silylation rate may be 100 mol%.
Further, when the precursor polymer (A ′) has an unsaturated group as a terminal group capable of introducing a reactive silicon group, for the same reason, the silylation rate is preferably 70 mol% or more, and 75 mol% or more. More preferred. The silylation rate may be 100 mol%.

The number average molecular weight (Mn) of the polymer (A) is 20,000 or more and 40,000 or less, preferably 20,000 or more and 30,000 or less. If it is 20,000 or more, the outflow of the polymer (B) from the cured product is satisfactorily suppressed. Moreover, durability of hardened | cured material becomes favorable. When the ratio is 40,000 or less, the composition tends to have a low viscosity, which is preferable for obtaining good workability. In particular, 20,000 or more and 28,000 or less are preferable in that excellent elongation of the cured product can be easily obtained.
1.0-1.8 are preferable and, as for molecular weight distribution (Mw / Mn) of a polymer (A), 1.0-1.3 are more preferable. If the molecular weight distribution (Mw / Mn) is within the above range as a polymer having a number average molecular weight (Mn) of 20,000 or more and 40,000 or less, the polymer has a number average molecular weight (Mn) of 100,000 or more and is heavy. The viscosity is low as a coalescence, but on the other hand, since there are few low molecular components with low viscosity, it is easy to obtain excellent elongation as a cured product. In view of this, 1.0 to 1.2 is more preferable.
The molecular weight distribution (Mw / Mn) of the polymer (A) can be controlled by the type of catalyst and polymerization conditions (temperature, stirring conditions, pressure, etc.).
When two or more kinds of polymers corresponding to the polymer (A) are used in combination, the number average molecular weight (Mn) and molecular weight distribution (Mw / Mn) per terminal in each of the polymers (A) before mixing. Should just be in said range.
The same applies to the polymer (B) described later.

Although the polymer (A) may have a reactive silicon group other than the reactive silicon group represented by the formula (1), the reaction of the polymer (A) from the viewpoint of excellent storage stability and elongation property. The reactive silicon group is preferably only the reactive silicon group represented by the formula (1).
The polymer (A) may be used alone or in combination of two or more.
When two or more kinds of polymers corresponding to the polymer (A) coexist in the curable composition, their reactive silicon groups may be the same as or different from each other.

<Polymer (B)>
The polymer (B) has a reactive silicon group represented by the above formula (1).
The reactive silicon group of the polymer (A) coexisting in the curable composition and the reactive silicon group of the polymer (B) may be the same or different from each other.

The polymer (B) is a polymer obtained by introducing a reactive silicon group into a precursor polymer (B ′) that is linear and capable of introducing a reactive silicon group at one end.
Specifically, one terminal group of both ends of the precursor polymer (B ′) is a reactive group, preferably a hydroxyl group or an unsaturated group, a group that reacts with the terminal group, and reactive silicon. It is preferable to introduce a reactive silicon group by reacting a compound having a group with the precursor polymer (B ′). The other terminal group of the precursor polymer (B ′) is preferably an inert organic group that does not have reactivity with the compound having a reactive silicon group.

The polymer (B) is preferably obtained by subjecting an initiator having one active hydrogen to an addition polymerization of an alkylene oxide monomer and / or a (meth) acrylic acid alkyl ester monomer.
That is, the repeating unit in the precursor polymer (B ′) and the polymer (B) preferably includes an alkylene oxide monomer unit and / or a (meth) acrylic acid alkyl ester monomer unit. It is preferable to have at least a chain of alkylene oxide monomer units, that is, a polyoxyalkylene chain.
It is preferable that the polymer (B) has a polyoxyalkylene chain because the compatibility with the polymer (A) is good and the storage stability is good.
Alternatively, as a part or all of the polymer (B), the repeating unit in the heavy precursor polymer (B ′) and the polymer (B) includes a (meth) acrylic acid alkyl ester monomer unit, and a polyoxyalkylene chain You may use the acrylic polymer which does not have. Such a polymer contributes to the weather resistance of the cured product, the adhesion between the cured product surface and the coating material, and the reduction of contamination.

As the precursor polymer (B ′), a linear precursor polymer (B′1) having a polyoxyalkylene chain and one end being a hydroxyl group; having a polyoxyalkylene chain and having one end not A linear precursor polymer (B′2) which is a saturated group is preferred.
The linear precursor polymer (B'1), which has a polyoxyalkylene chain and one end is a hydroxyl group, undergoes ring-opening addition of alkylene oxide to an initiator having one active hydrogen in the presence of a catalyst. It can be produced by polymerization.
Specific examples of the initiator include an aliphatic monool having 1 to 20 carbon atoms, an alicyclic monool having 1 to 20 carbon atoms, an aromatic monool having 1 to 20 carbon atoms, a thiol, a secondary amine, and a carboxylic acid. Or a polyoxyalkylene monool having a hydroxyl equivalent molecular weight MW (OH) of 300 to 5,000 obtained by ring-opening addition polymerization of alkylene oxide to the monool. More preferred is a polyoxyalkylene monool having a hydroxyl equivalent molecular weight MW (OH) of 300 to 3,300. An unsaturated group-containing monohydroxy compound such as allyl alcohol can also be used. An initiator may be used individually by 1 type and may use 2 or more types together.
The alkylene oxide and catalyst used for the synthesis of the precursor polymer (B′1) or initiator are the same as the alkylene oxide and catalyst used for the synthesis of the precursor polymer (A′1) described above, including preferred embodiments. is there.
The precursor polymer (B′1) is preferably a polyoxypropylene monool.

The linear precursor polymer (B′2) having a polyoxyalkylene chain and one end being an unsaturated group is a hydroxyl group (—OH) of the precursor polymer (B′1) having one end being a hydroxyl group. ) Is converted to -OM (M is an alkali metal) and then reacted with an unsaturated group-containing halogenated hydrocarbon such as allyl chloride. This method is general and is preferable in terms of easy availability of raw materials and high reaction yield.
Alternatively, a method in which a compound having a functional group capable of reacting with a hydroxyl group and an unsaturated group is reacted with the precursor polymer (B′1) to introduce an unsaturated group via an ester bond, a urethane bond, a carbonate bond, or the like. can get.

As a method for obtaining the polymer (B) by introducing a reactive silicon group into the terminal unsaturated group of the precursor polymer (B′2), a known method can be used. For example, the above method [1] or [2] can be used.
As a method for obtaining the polymer (B) by introducing a reactive silicon group into the terminal hydroxyl group of the precursor polymer (B′1), a known method can be used. For example, the above method [3] or [4] can be used.

In the polymer (B), the ratio (silylation rate) of the terminal group substituted with the reactive silicon group among the terminal groups capable of introducing the reactive silicon group in the precursor polymer (B ′) is 60 to 100 mol. %.
The silylation rate in the polymer (B) is determined by reacting the terminal reactive group of the precursor polymer (B ′) with a compound having a reactive silicon group. And the reactive silicon group and the molar ratio can be controlled.
When the silylation rate at one end of the polymer (B) is 60 mol% or more, the plasticizer has low migration and the contamination around the sealing material portion and adhesion are improved.
In particular, when the precursor polymer (B ′) has a hydroxyl group as a terminal group capable of introducing a reactive silicon group, the ratio of the terminal group substituted with the reactive silicon group out of all the hydroxyl groups (silylation rate) Is preferably 60 mol% or more, more preferably 75 mol% or more from the above point.
Similarly, when the precursor polymer (B ′) has an unsaturated group as a terminal group capable of introducing a reactive silicon group, for the same reason, the silylation rate is preferably 60 mol% or more, preferably 75 mol%. The above is more preferable. The silylation rate may be 100 mol%.

The number average molecular weight (Mn) of the polymer (B) is 3,000 or more and 20,000 or less, preferably 3,000 or more and 15,000 or less, more preferably 5,000 or more and 12,000. It is as follows. If the number average molecular weight (Mn) is 3,000 or more, even if the polymer (B) has a reactive silicon group, there is no contamination around the sealing material part, the adhesion is improved, and the cured product is Good physical properties. When it is 20,000 or less, the viscosity of the polymer (B) becomes low, and it works effectively as a plasticizer.
1.0-1.8 are preferable and, as for molecular weight distribution (Mw / Mn) of a polymer (B), 1.0-1.3 are more preferable. It is easy to manufacture in this range. Moreover, workability when the viscosity as a polymer is low and a curable composition is obtained is improved, and stickiness at the time of curing can be reduced. More preferable Mw / Mn is 1.0 to 1.3.
The molecular weight distribution (Mw / Mn) of the polymer (B) can be controlled by the type of catalyst and polymerization conditions (temperature, stirring conditions, pressure, etc.).

The polymer (B) may have a reactive silicon group other than the reactive silicon group represented by the formula (1), but from the viewpoint of excellent storage stability and elongation property, the polymer (B) The reactive silicon group is preferably only the reactive silicon group represented by the formula (1).
A polymer (B) may be used individually by 1 type, and may use 2 or more types together.
When two or more kinds of polymers corresponding to the polymer (B) coexist in the curable composition, their reactive silicon groups may be the same as or different from each other.
In the polymer (B), the molecular end group other than the reactive silicon group is preferably an inert organic group. For example, when an unsaturated group-containing monohydroxy compound such as allyl alcohol is used as an initiator, a precursor polymer (B′1) is obtained in which one terminal group is a hydroxyl group and the other terminal group is an unsaturated group. . When a reactive silicon group is introduced into the terminal unsaturated group to obtain the polymer (B), the terminal hydroxyl group is preferably converted to an inert organic group by a method such as reacting with benzoyl chloride.

The curable composition of this invention contains a polymer (A) and a polymer (B). The mass ratio (A / B) of the content of the polymer (A) and the content of the polymer (B) is 95/5 to 5/95, preferably 85/15 to 50/50, more preferably 80. / 20 to 50/50.
Of the total 100% by mass of the polymer (A) and the polymer (B), a sufficient low viscosity effect is obtained when the polymer (B) is 5% by mass or more, and the curability is 95% by mass or less. The composition is cured and is useful as a curable composition for sealing materials and adhesives.

<Other ingredients>
The curable composition of this invention can contain a well-known component in a curable composition other than a polymer (A) and (B). Specifically, a curing catalyst, a filler, an additive, a solvent, a plasticizer, and the like. In addition, as an optional component, a polymer other than the polymers (A) and (B) is an acrylic or polyisobutylene having a reactive silicon group in order to improve the weather resistance and adhesion as long as the physical properties are not impaired. , Silicon or polyurethane polymers can be used.

<Curing catalyst>
The following compounds can be used as the curing catalyst.
Metal salts such as alkyl titanates, organosilicon titanates, bismuth tris-2-ethylhexoate; acidic compounds such as phosphoric acid, p-toluenesulfonic acid, phthalic acid; butylamine, hexylamine, octylamine, decylamine Aliphatic diamines such as ethylenediamine and hexanediamine; aliphatic polyamines such as diethylenetriamine, triethylenetetramine and tetraethylenepentamine; heterocyclic amines such as piperidine and piperazine; metaphenylene Amine compounds such as aromatic amines such as diamines; ethanolamines; various modified amines used as curing agents for triethylamine and epoxy resins.
A mixture of divalent tin such as tin dioctylate (bis (2-ethylhexanoate) tin), tin dinaphthenate and tin distearate and the above amines as a co-catalyst.

Dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate and the following carboxylic acid type organic tin compounds; a mixture of these carboxylic acid type organic tin compounds and the above amines.
_{(N-C 4 H 9)} 2 Sn (OCOCH = CHCOOCH 3) 2,
_{(N-C 4 H 9)} 2 Sn (OCOCH = CHCOOC 4 H 9 -n) 2,
_{(N-C 8 H 17)} 2 Sn (OCOCH = CHCOOCH 3) 2,
_{(N-C 8 H 17)} 2 Sn (OCOCH = CHCOOC 4 H 9 -n) 2,
_{(N-C 8 H 17)} 2 Sn (OCOCH = CHCOOC 8 H 17 -iso) 2.

The following sulfur-containing organotin compounds.
_{(N-C 4 H 9)} 2 Sn (SCH 2 COO),
_{(N-C 8 H 17)} 2 Sn (SCH 2 COO),
_{(N-C 8 H 17)} 2 Sn (SCH 2 CH 2 COO),
_{(N-C 8 H 17)} 2 Sn (SCH 2 COOCH 2 CH 2 OCOCH 2 S),
_{(N-C 4 H 9)} 2 Sn (SCH 2 COOC 8 H 17 -iso) 2,
_{(N-C 8 H 17)} 2 Sn (SCH2COOC 8 H 17 -iso) 2,
_{(N-C 8 H 17)} 2 Sn (SCH2COOC 8 H 17 -n) 2,
_{(N-C 4 H 9)} 2 SnS.

_{(N-C 4 H 9)} 2 SnO, (n-C 8 H 17) 2 organotin oxide SnO or the like; and these organic tin oxide and ethyl silicate, dimethyl maleate, diethyl maleate, dioctyl maleate, phthalic Reaction products with ester compounds such as dimethyl acid, diethyl phthalate and dioctyl phthalate.

The following chelated tin compounds and reaction products of these tin compounds and alkoxysilanes (where acac is an acetylacetonato ligand).
_{(N-C 4 H 9)} 2 Sn (acac) 2,
_{(N-C 8 H 17)} 2 Sn (acac) 2,
_{(N-C 4 H 9)} 2 (C 8 H 17 O) Sn (acac).

The following tin compounds.
_{(N-C 4 H 9)} 2 (CH 3 COO) SnOSn (OCOCH 3) (n-C 4 H 9) 2,
_{(N-C 4 H 9)} 2 (CH 3 O) SnOSn (OCH 3) (n-C 4 H 9) 2.

<Filler>
As the filler, for example, the following fillers can be used.
Calcium carbonate whose surface is treated with a fatty acid or resin acid organic substance, finely powdered colloidal calcium carbonate having an average particle size of 1 μm or less, light calcium carbonate having an average particle size of 1 to 3 μm and an average particle produced by a precipitation method Calcium carbonate such as heavy calcium carbonate having a diameter of 1 to 20 μm, fume silica, precipitated silica, anhydrous silicic acid, hydrous silicic acid and carbon black, magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium oxide, bentonite, Organic bentonite, organic resin balloon, ferric oxide, zinc oxide, activated zinc white, shirasu balloon, wood flour, pulp, cotton chip, mica, walnut flour, rice flour, graphite, aluminum fine powder, flint powder, etc. Filler. Fibrous fillers such as asbestos, glass fiber, glass filament, carbon fiber, Kevlar fiber, polyethylene fiber.

  The amount of the filler used is preferably 1 to 1,000 parts by mass and more preferably 50 to 250 parts by mass with respect to 100 parts by mass in total of the polymer (A) and the polymer (B). These fillers may be used alone or in combination of two or more.

<Plasticizer>
A plasticizer may be contained in addition to the polymer (B).
Examples of the plasticizer include dioctyl phthalate, dibutyl phthalate, diisononyl phthalate (diisononyl phthalate), phthalic acid alkyl esters such as butyl benzyl phthalate; dioctyl adipate, diisodecyl succinate, dibutyl sebacate, butyl oleate, etc. Aliphatic carboxylic acid alkyl esters; glycol esters such as pentaerythritol ester; phosphate esters such as trioctyl phosphate and tricresyl phosphate; epoxy plasticizers such as epoxidized soybean oil and epoxy benzyl stearate; Paraffin; etc. can be used alone or in a mixture of two or more.
However, among such plasticizers, there is a problem that a low molecular weight plasticizer tends to bleed out after curing of the curable composition of the present invention. Therefore, it is preferable not to use a low molecular weight plasticizer. That is, when the curable composition of the present invention further contains a plasticizer, it is preferable not to contain a low molecular weight plasticizer as the plasticizer. The low molecular weight plasticizer refers to a plasticizer whose compound itself has a low molecular weight and does not have a reactive group. For example, alkyl phthalates.
Polyoxyalkylene polyols such as polypropylene polyol can also be used as a plasticizer. The number average molecular weight (Mn) of the polyoxyalkylene polyol is preferably 1,000 to 20,000, more preferably 3,000 to 15,000.

<Dehydrating agent>
In order to further improve the storage stability, a small amount of a dehydrating agent can be added to the curable composition as long as it does not adversely affect the curability and flexibility. Examples of the dehydrating agent include alkyl orthoformate such as methyl orthoformate and ethyl orthoformate, alkyl orthoacetate such as methyl orthoacetate and ethyl orthoacetate, methyltrimethoxysilane, vinyltrimethoxysilane, tetramethoxysilane and tetraethoxysilane. Examples include hydrolyzable organic silicon compounds and hydrolyzable organic titanium compounds. Among these, vinyltrimethoxysilane and tetraethoxysilane are particularly preferable from the viewpoint of cost and effect. In particular, it is effective to use a one-pack type agent in which the curable composition contains a curing catalyst and is filled in a moisture-proof container.

<Adhesive agent>
Specific examples of the adhesion-imparting agent include organosilane coupling agents such as silane having a vinyl group, silane having an epoxy group, silane having an amino group, and silane having a carboxy group; isopropyltri (N-aminoethyl-amino) And organic metal coupling agents such as ethyl) propyltrimethoxytitanate and 3-mercaptopropyltrimethotitanate; and epoxy resins.
Specific examples of the silane having an epoxy group include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, and 3-glycidyloxypropyltriethoxysilane.
Specific examples of the silane having an amino group include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxy. Silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, 3-ureidopropyltriethoxysilane, N-[(N- Vinylbenzyl) -2-aminoethyl] -3-aminopropyltrimethoxysilane, 3-anilinopropyltrimethoxysilane and the like.

<Other additives>
In the curable composition of the present invention, a reactive silicon group-containing compound having a molecular weight of less than 300 may be optionally added for the purpose of adjusting the physical properties and curability of the cured product. Specific examples of such compounds include tetramethyl silicate, vinyltrimethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, and the like, and compounds in which these methoxy groups are substituted with ethoxy groups.
Examples of other additives include a thixotropic agent; a pigment; various stabilizers; a photocurable compound for the purpose of surface modification such as an oligoester acrylate, and the like. A solvent can also be used for the purpose of adjusting the viscosity.

<Modulus modifier>
As other additives, a modulus adjusting agent may be used. The modulus modifier refers to a compound that can generate trimethylsilanol by hydrolysis. For example, a compound containing a trimethylsilyloxy group in the molecule. Trimethylsilanol generated by hydrolysis of the modulus modifier reacts with the polymer (A) or the polymer (B), and therefore the mechanical properties of the curable composition can be changed.
Specific examples of the modulus regulator include phenoxytrimethylsilane, 2,2-bis [(trimethylsiloxy) methyl] -1- (trimethylsiloxy) butane, and the like. 1 type may be used independently and 2 or more types may be used together.
The modulus modifier is not particularly limited as long as it has a functional group capable of generating trimethylsilanol, such as a trimethylsilyloxy group, but a compound having a molecular weight of 2,000 or less is preferable, and a compound having a molecular weight of 500 or less is more preferable. In addition, the average number of functional groups capable of generating trimethylsilanol is preferably 0.5 to 8.0 or less, and more preferably 0.9 to 4.0 on average.

Examples of the modulus regulator include monohydric alcohols such as methanol, ethanol, 2-ethylhexanol and phenol; polyhydric alcohols such as ethylene glycol, propanediol, trimethylolpropane, glycerin, pentaerythritol and sorbitol; hydroxyl groups of alcohols such as A compound obtained by trimethylsilyloxylation of is preferred. Examples of the compound to be trimethylsilyloxylated include 1,1,1,3,3,3-hexamethyldisilazane and trimethylchlorosilane.
Although the trimethylsilyloxylation rate in all the hydroxyl groups of a polyhydric alcohol can be adjusted arbitrarily, 50% or more is preferable and 80% or more is more preferable. Most preferably, substantially all hydroxyl groups are trimethylsilyloxylated.
The usage-amount of a modulus regulator is not specifically limited, A usage-amount can be freely set according to the physical property of the target hardened | cured material. Usually, 0.1-10.0 mass parts is preferable with respect to 100 mass parts of a polymer (A), and 0.1-5.0 mass parts is more preferable. In addition, for the purpose of adjusting the curing speed, several types of modulus adjusting agents may be used in combination.
Further, the modulus adjusting agent may be added in advance to one or both of the polymer A and the polymer B, or may be added when producing the curable composition.

<Curable composition>
The curable composition of the present invention can be prepared as a one-component type in which all compounding components are preliminarily blended and stored and cured by moisture in the air after construction. Polymers (A) and (B) In addition to the main component containing, a curing agent composition is prepared as a two-component type in which components such as a curing catalyst, a filler, and water are blended, and the curing agent composition and the main component are mixed before use. You can also.

In the case of the one-component type, since all the blended components are blended in advance, it is preferable that the blended components containing moisture be used after being dehydrated and dried in advance or dehydrated under reduced pressure during blending and kneading.
In the case of the two-component type, since there is no need to blend a curing catalyst in the main agent containing a polymer having a reactive silicon group, there is little concern about gelation even if some moisture is contained in the main agent, When long-term storage stability is required, it is preferable to perform dehydration drying.
As the dehydration and drying method, a heat drying method is preferable in the case of a solid substance such as a powder, and a dehydration method using a reduced pressure dehydration method or a synthetic zeolite, activated alumina, silica gel or the like is preferable in the case of a liquid material. Alternatively, a small amount of an isocyanate compound may be blended to react with an isocyanate group and water for dehydration. In addition to the dehydration drying method, lower alcohols such as methanol and ethanol; n-propyltrimethoxysilane, vinyltrimethoxysilane, vinylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxysilane, γ -Storage stability is further improved by adding an alkoxysilane compound such as glycidoxypropyltrimethoxysilane.
The amount of silicon compound capable of reacting with water such as dehydrating agent, especially vinyltrimethoxysilane, is 0.1 to 20.0 mass per 100 mass parts of the total amount of the polymer (A) and the polymer (B). Part is preferable, and 0.5 to 10.0 parts by mass is more preferable.

  The curable composition of the present invention comprises a sealing material (an elastic sealing material sealant for construction, a sealing material for multi-layer glass, etc.); a sealing agent (a sealing agent for rust prevention and waterproofing at the glass edge, a solar cell back surface sealing It is useful as an adhesive used in fields such as electrical insulating materials (insulating coatings for electric wires and cables). Moreover, the curable composition of this invention can be used also for uses, such as an adhesive, a coating material, a film material, a gasket material, a casting material.

The present invention will be specifically described below, but the present invention is not limited to the examples. Examples 2 to 5, 7 to 10, 12 to 15, 21 to 25, 31 to 33, 35 to 37, 5 to 54 are Examples, Examples 1, 6, 11, 26, 34, 38, 43, 55 -57 is a comparative example , and Examples 39-42 are reference examples .
<Production Example 1: Production of polymer (A-1)>
Polyoxypropylene diol (hydroxyl equivalent molecular weight MW (OH) 2,000) obtained by ring-opening addition polymerization of propylene oxide to propylene glycol was used as an initiator (referred to as initiator A).
Propylene oxide (512.8 g) was added to initiator A (64.1 g) in the presence of a t-butanol complex catalyst (0.03 g) of zinc hexacyanocobaltate, and the pressure of the reaction system was lowered at 120 ° C. The reaction was continued until it disappeared. As a result, a polymer (h1) having a polyoxypropylene chain and having two hydroxyl groups per molecule at the molecular end was obtained. The viscosity of the polymer (h1) at 25 ° C. was 17.4 Pa · s. Mn measured by GPC was 24,000, Mw was 26,000, and thus Mw / Mn was 1.1.

  To the obtained polymer (h1), a methanol solution containing 1.05 times moles of sodium methoxide with respect to the amount of hydroxyl groups of the polymer (h1) was added to alcoholate the polymer (h1). Next, after distilling off methanol by heating under reduced pressure, an excessive amount of allyl chloride was added relative to the amount of hydroxyl groups in the polymer (h1). As a result, a polymer (v1) having a polyoxypropylene chain and having an allyl group at the molecular end was obtained.

Next, in the presence of chloroplatinic acid hexahydrate, 0.6 times moles of dimethoxymethylsilane is added to the terminal allyl group of the obtained polymer (v1), and the mixture is added at 70 ° C. for 5 hours. Reacted. As a result, a polymer (A-1) having a polyoxypropylene chain and having a dimethoxymethylsilyl group at the molecular end was obtained. The viscosity of the polymer (A-1) at 25 ° C. was 18.5 Pa · s. Mn measured by GPC was 24,000, Mw was 27,000, and thus Mw / Mn was 1.1. The polymer (A-1) was a polymer in which a dimethoxymethylsilyl group was introduced into 60% of the allyl groups at the molecular terminals of the polymer (v1).
The number of functional groups of the obtained polymer (A-1) (the number of active hydrogens in the initiator becomes the number of functional groups of the polymer. The same applies hereinafter), Mn, Mw / Mn, silylation rate (Si conversion rate) The viscosity at 25 ° C. is shown in Table 1 (the same applies hereinafter).

<Production Examples 2 and 3: Production of polymers (A-2) and (A-3)>
Except having adjusted the preparation amount of dimethoxymethylsilane, the polymer (A-2) and (A-3) were obtained like the synthesis | combination of the polymer (A-1).

<Production Example 4: Production of polymer (A-4)>
A polymer (h2) was obtained in the same manner as in Production Example 1 except that the amount of propylene oxide reacted with initiator A (64.1 g) in Production Example 1 was changed to 641.0 g. The viscosity of the polymer (h2) was 28.5 Pa · s, Mn was 27,000, Mw was 30,000, and Mw / Mn was 1.1.

  Subsequently, in the same manner as in Production Example 1, a polymer (v2) having a polyoxypropylene chain and having an allyl group at the molecular end is obtained from the polymer (h2), and this is reacted with dimethoxymethylsilane. Thus, a polymer (A-4) having a polyoxypropylene chain and having a dimethoxymethylsilyl group at the molecular end was obtained.

<Production Examples 5 and 6: Production of polymers (A-5) and (A-6)>
Except having adjusted the preparation amount of dimethoxymethylsilane, it carried out similarly to synthesize | combining a polymer (A-4), and obtained the polymer (A-5) and (A-6).

<Production Example 7: Production of polymer (A-7)>
In Production Example 1, a polymer (h3) was obtained in the same manner as in Production Example 1, except that the amount of propylene oxide reacted with initiator A (64.1 g) was changed to 705.1 g. The viscosity of the polymer (h3) at 25 ° C. was 38.0 Pa · s, Mn was 29,000, Mw was 38,000, and thus Mw / Mn was 1.3.

  Subsequently, except that a glyme complex catalyst of zinc hexacyanocobaltate was used instead of the t-butanol complex catalyst of zinc hexacyanocobaltate in Production Example 1, and methallyl chloride was used instead of allyl chloride, Production Example 1 and Similarly, a polymer (v3) having a polyoxypropylene chain and having a methallyl group at the molecular end is obtained, and this is reacted with dimethoxymethylsilane to have a polyoxypropylene chain and having dioxymethyl at the molecular end. A polymer (A-7) having a methylsilyl group was obtained.

<Production Examples 8 to 10: Production of polymers (A-8) to (A-10)>
Except having adjusted the preparation amount of dimethoxymethylsilane, it carried out similarly to synthesize | combining a polymer (A-7), and obtained the polymer (A-8)-(A-10).

<Production Example 11: Production of polymer (B-1)>
Polyoxypropylene monool obtained by ring-opening addition polymerization of propylene oxide to t-butanol (hydroxyl equivalent molecular weight MW (OH) 2,000) was used as an initiator (referred to as initiator B).
Propylene oxide (249.6 g) is added to initiator B (384 g) in the presence of a zinc hexacyanocobaltate t-butanol complex catalyst (0.03 g) until the pressure of the reaction system does not drop at 120 ° C. Reacted. As a result, a polymer (h4) having a polyoxypropylene chain and having one hydroxyl group per molecule at the molecular end was obtained. The viscosity of the polymer (h4) at 25 ° C. was 0.45 Pa · s. Mn measured by GPC was 4,700, Mw was 5,100, and thus Mw / Mn was 1.08.

  To the obtained polymer (h4), a methanol solution containing 1.05 times moles of sodium methoxide was added to the amount of hydroxyl groups of the polymer (h4) to alcoholate the polymer (h4). Next, after distilling off methanol by heating under reduced pressure, an excessive amount of allyl chloride relative to the amount of hydroxy groups of the polymer (h4) was added. Thereby, a polymer (v4) having a polyoxypropylene chain and having an allyl group at the molecular end was obtained.

Next, in the presence of chloroplatinic acid hexahydrate, 1.05 times moles of dimethoxymethylsilane with respect to the amount of allyl group at the terminal of the obtained polymer (v4) was added, and the mixture was kept at 70 ° C. for 5 hours. Reacted. Thereby, a polymer (B-1) having a polyoxypropylene chain and having a dimethoxymethylsilyl group at the molecular end was obtained.
The number of functional groups, Mn, Mw / Mn, silylation rate (Si conversion rate), and viscosity at 25 ° C. of the obtained polymer (B-1) are shown in Table 2 (the same applies hereinafter).

<Production Example 12: Production of polymer (B-2)>
In Production Example 11, the t-butanol complex catalyst of zinc hexacyanocobaltate was changed to 0.05 g, and the amount of propylene oxide reacted with initiator B (384 g) was changed to 576 g. Thus, a polymer (h5) was obtained. The viscosity of the polymer (h5) at 25 ° C. was 1.20 Pa · s, Mn was 7,300, Mw was 8,100, and Mw / Mn was 1.10.
Subsequently, a polymer (v5) having a polyoxypropylene chain and having an allyl group at the molecular end is obtained from the polymer (h5) in the same manner as in Production Example 11, and this is reacted with dimethoxymethylsilane. A polymer (B-2) having a polyoxypropylene chain and having a dimethoxymethylsilyl group at the molecular end was obtained.

<Production Example 13: Production of polymer (B-3)>
In Production Example 11, Production Example 11 except that the amount of zinc hexacyanocobaltate t-butanol complex catalyst used was changed to 0.07 g and the amount of propylene oxide reacted with initiator B (384 g) was changed to 960 g. In the same manner as above, a polymer (h6) having a polyoxypropylene chain and having one hydroxy group per molecule at the molecular end was obtained. The viscosity of the polymer (h6) at 25 ° C. was 3.3 Pa · s, Mn was 10,100, Mw was 11,700, and Mw / Mn was 1.15.

  Subsequently, a polymer (v6) having a polyoxypropylene chain and having an allyl group at the molecular end is obtained from the polymer (h6) in the same manner as in Production Example 11, and this is reacted with dimethoxymethylsilane. A polymer (B-3) having a polyoxypropylene chain and having a dimethoxymethylsilyl group at the molecular end was obtained.

<Production Example 14: Production of polymer (B-4)>
In Production Example 11, Production Example 11 except that the amount of zinc hexacyanocobaltate t-butanol complex catalyst used was changed to 0.09 g and the amount of propylene oxide reacted with initiator B (384 g) was changed to 1440 g. In the same manner as above, a polymer (h7) having a polyoxypropylene chain and having one hydroxy group per molecule at the molecular end was obtained. The viscosity of the polymer (h7) at 25 ° C. was 4.6 Pa · s, Mn was 14,100, Mw was 16,000, and Mw / Mn was 1.14.

  Subsequently, a polymer (v7) having a polyoxypropylene chain and having an allyl group at the molecular end was obtained from the polymer (h7) in the same manner as in Production Example 11, and this was reacted with dimethoxymethylsilane. A polymer (B-4) having a polyoxypropylene chain and having a dimethoxymethylsilyl group at the molecular end was obtained.

<Production Example 15: Production of comparative polymer (C-1)>
Comparative polymer (C-1) is a polyoxypropylene triol obtained by ring-opening addition polymerization of propylene oxide to glycerin (hydroxyl equivalent molecular weight MW (OH) 5,000) (referred to as initiator C), Polyoxypropylene diol (hydroxyl equivalent molecular weight MW (OH) 3,200) (referred to as initiator D) obtained by ring-opening addition polymerization of propylene oxide to propylene glycol was used as an initiator.
In the presence of a zinc hexacyanocobaltate glyme complex catalyst (0.23 g), initiator C (64.1 g) was reacted with propylene oxide (435.9 g) at 120 ° C. until the pressure of the reaction system was not lowered. It was. Next, initiator C (58.3 g) was added and propylene oxide (291.7 g) was reacted until the pressure in the reaction system did not drop. Subsequently, initiator D (57.6 g) was added, and propylene oxide (392.4 g) was reacted until the pressure in the reaction system did not drop.
Further, initiator D (44.4 g) was added, and propylene oxide (205.6 g) was reacted until the pressure in the reaction system did not drop. As a result, a polymer (h8) having a polyoxypropylene chain and having 2.4 hydroxyl groups per molecule at the molecular terminals was obtained. The viscosity of the polymer (h8) at 25 ° C. was 17.4 Pa · s. Mn measured by GPC was 19,000, Mw was 29,000, and thus Mw / Mn was 1.5.
To the obtained polymer (h8), a methanol solution containing 1.05 times moles of sodium methoxide was added to the polymer (h8) to form an alcoholate. Next, after distilling off methanol by heating under reduced pressure, an excessive amount of allyl chloride was added relative to the amount of hydroxy groups of the polymer (h8). As a result, a polymer (v5) having a polyoxypropylene chain and having allyl groups at all terminals was obtained.
Next, in the presence of 1,1,3,3-tetramethyldivinylsiloxane platinum complex, 0.84 times mol of dimethoxymethylsilane was added to the amount of allyl group at the terminal of the obtained polymer (v5). And reacted at 70 ° C. for 5 hours. Thereby, a polymer (C-1) having a polyoxypropylene chain and having a dimethoxymethylsilyl group at the molecular end was obtained. Table 3 shows the number of functional groups, Mn, Mw / Mn, silylation rate (Si conversion rate), and viscosity at 25 ° C. of the obtained comparative polymer (C-1). In addition, since a polymer (C-1) is a polymer manufactured using 2 types of initiators, the functional group number of a polymer is represented by an average functional group number. The average value of the number of active hydrogens in the initiator is the average number of functional groups of the polymer.

<Production Example 16: Production of comparative polymer (C-2)>
In the presence of zinc hexacyanocobaltate complex catalyst (0.03 g), propylene oxide (320.5 g) was added to initiator A (64.1 g) and allowed to react at 120 ° C. until the pressure of the reaction system did not drop. It was. As a result, a polymer (h9) having a polyoxypropylene chain and having two hydroxyl groups per molecule at the molecular end was obtained. The viscosity of the polymer (h9) at 25 ° C. was 7.5 Pa · s. Mn measured by GPC was 17,000, Mw was 19,000, and thus Mw / Mn was 1.1.
To the obtained polymer (h9), a methanol solution containing 1.05 times moles of sodium methoxide with respect to the amount of hydroxyl group of the polymer (h9) was added to alcoholate the polymer (h9). Next, after distilling off methanol by heating under reduced pressure, an excessive amount of allyl chloride was added relative to the amount of hydroxyl group in the polymer (h9). As a result, a polymer (v6) having a polyoxypropylene chain and having allyl groups at all terminals was obtained.
Next, in the presence of chloroplatinic acid hexahydrate, 0.84 moles of dimethoxymethylsilane was added to the terminal allyl group of the obtained polymer (v6), and the mixture was added at 70 ° C. for 5 hours. Reacted. Thus, a polymer (C-2) having a polyoxypropylene chain and having a dimethoxymethylsilyl group at the molecular end was obtained. Table 3 shows the number of functional groups, Mn, Mw / Mn, silylation rate (Si conversion rate), and viscosity at 25 ° C. of the obtained comparative polymer (C-2).

<Other additives>
The additives used in the following examples are as follows.
[Plasticizer (1)] Diisononyl phthalate (abbreviation: DINP) (trade name: Vinicizer 90, manufactured by Kao Corporation).
[Plasticizer (2)] Polypropylene glycol (manufactured by Asahi Glass Co., Ltd., trade name: PREMINOL S4011, MW (OH) = 10,000).
[Filler (1)] Colloidal calcium carbonate (manufactured by Shiroishi Kogyo Co., Ltd., trade name: Baiyinhua CCR)
[Filler (2)] Heavy calcium carbonate (manufactured by Shiroishi Calcium Industry Co., Ltd., trade name: Whiten SB, average particle size 1.78 μm)
[Filler (3)] A mixture of the filler (1) / the filler (2) = 1/1 (mass ratio).
[Filler (4)] Organic balloon (Matsumoto Yushi Co., Ltd., trade name: 80-GCA)
[Filler (5)] Kaolin clay (manufactured by Takehara Chemical Industry Co., Ltd., trade name: Glomax LL)
[Filler (6)] Titanium oxide (Ishihara Sangyo Co., Ltd., trade name: R820). Weathering agent.
[Thixotropic agent (1)] Fatty acid amide type thixotropic agent (manufactured by Enomoto Kasei Co., Ltd., trade name: Disparon # 6500).
[Thixotropic agent (2)] Hydrogenated castor oil-based thixotropic agent (manufactured by Enomoto Kasei Co., Ltd., trade name: Disparon # 305).
[Modulus Modifier] Tristrimethylsilyl derivative of trimethylolpropane.
[Stabilizer (1)] Benzotriazole UV absorber (Ciba Specialty Chemicals, trade name: Tinuvin 326) / Hindered phenol antioxidant (Ciba Specialty Chemicals, product) Name: Irganox 1010) = 1/1 (mass ratio).
[Stabilizer (2)] A mixture of ultraviolet absorber, hindered amine and antioxidant (Ciba Specialty Chemicals, trade name: Tinuvin B75).
[Adhesiveness imparting agent] Vinyl group-containing silane coupling agent (Shin-Etsu Chemical Co., Ltd., trade name: KBM1003 / amino group-containing silane coupling agent (Shin-Etsu Chemical Co., Ltd., trade name: KBM603) / Epoxy group-containing silane cup Ring agent (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KBM403) = 3/1/1 (mass ratio).
[Photo-curable compound] Polyfunctional acrylic group-containing compound (trimethylolpropane triacrylate, manufactured by Toagosei Co., Ltd., trade name: Aronix M-309).
[One-component curing agent] Tetravalent organotin compound (Asahi Glass Co., Ltd .: EXCESTAR C201)
[Two-component curing agent composition] Mixtures (a) to (d) below.
(A) Mass ratio of bis (2-ethylhexanoic acid) tin (manufactured by API Corporation) as a curing catalyst and laurylamine (manufactured by Wako Pure Chemical Industries, Ltd.) as a cocatalyst (curing catalyst: cocatalyst) 4 parts by weight of 6: 1 mixture.
(B) 6 parts by mass of diisononyl phthalate (abbreviation: DINP, plasticizer (1)).
(C) 15 parts by mass of heavy calcium carbonate (trade name: Whiten SB, the filler (2)).
(D) 5 parts by mass of kaolin clay (trade name: Glomax LL, filler (5) above).

[Examples 1 to 15]
Using the polymer obtained in the above production example, each component was mixed according to the formulation shown in Table 4, and the viscosity at 25 ° C. of the obtained mixture was measured. The results are shown in Table 4.

  As shown in the results in Table 4, the viscosity of the mixture of the polymer (A) and the polymer (B) is lower than the viscosity of the polymer (A). The viscosity of Examples 2-5 is lower than the viscosity of Example 1, the viscosity of Examples 7-10 is lower than the viscosity of Example 6, and the viscosity of Examples 12-15 is lower than the viscosity of Example 11. That is, it can be confirmed that the polymer (B) works as a plasticizer.

[Examples 21-26, 31-43]
Using the polymers obtained in the above production examples, the components shown in Tables 5 and 6 were mixed to produce a one-component curable composition, and workability and tensile properties of the cured product were determined by the following method. Measured with The results are shown in Tables 5 and 6.

(Workability)
The spatability and ease of handling when a test piece of a cured product was prepared using each curable composition were evaluated. Spatility refers to the property when the paste-like curable composition before curing is handled with a spatula. If the curable composition easily pulls the yarn, it is difficult to handle and the workability is poor. . The ease of handling refers to the ease of handling when a paste-like curable composition before curing is kneaded with a spatula, and is affected by the viscosity and thixotropy of the curable composition. “◎ (excellent)” indicates that spatability and ease of handling are particularly good, “○ (good)” indicates that both are good, and “△ (possible)” indicates that one is good. Those that were not good in all were defined as “x (defect)”.

(Tensile properties)
A test piece made of a cured product of the curable composition obtained in each example was prepared, and a tensile test was performed. The tensile test was performed according to JIS K 6251.
Specifically, the curable composition was formed into a sheet having a thickness of 2 mm, cured for 7 days at 23 ° C. and 50% humidity, and then cured for 7 days at 50 ° C. and 65% humidity. Furthermore, it was left to stand for 24 hours or more at 23 ° C. and 50% humidity to obtain a cured product. The obtained sheet-like cured product was punched into a No. 3 dumbbell shape to obtain a test piece. After measuring the thickness of the test piece, using a Tensilon tester, the stress at 50% elongation (M50, unit: N / mm ² ), maximum tensile stress (Tmax, unit: N / mm ² ), fracture The amount of elongation at the time (E, unit:%) was measured.
The lower the M50, the higher the flexibility, the higher the Tmax, the higher the tensile bond strength, and the higher the E, the better the elongation.

As shown in Table 5, in Examples 21 to 25 in which the curable composition contains a polymer (A) and a polymer (B), and their mass ratio (A / B) is within the scope of the present invention. It was confirmed that the workability of the curable composition was good, and the tensile properties (flexibility (M50) and elongation (E)) of the cured product obtained by curing the curable composition were also good. In particular, M50 was low and elongation (E) was high. On the other hand, Example 26 which does not contain a polymer (B) has especially high M50 and low elongation (E) compared with Examples 21-25.
As shown in Table 6, in Examples 31 to 33, 35 to 37, and 39 to 42 in which the curable composition contains the polymer (A) and the polymer (B), the workability of the curable composition is good. The tensile properties (flexibility and elongation) of the cured product obtained by curing the curable composition were also confirmed to be good.
On the other hand, Examples 34, 38 and 43 which do not contain the polymer (B) have a particularly high M50 and a low elongation (E) as compared with Examples 33, 37 and 42, respectively.
In addition, the examples using the polymers (A-1) to (A-6) as the polymer A have better workability and the elongation than the examples using the polymers (A-7) to (A-10). (E) is excellent.

[Examples 51 to 57]
Using the polymer obtained in the above production example, the components shown in Table 7 were mixed to produce a two-component curable composition (main agent). About 100 parts by mass of the main agent and 10 parts by mass of the two-component curing agent composition, and curing the mixture, the H-type physical properties / tensile properties, coating film contamination, durability, surface The stickiness was evaluated by the following method. The results are shown in Table 7.
(H type physical properties and tensile properties)
Aluminum was used as the adherend, and a tensile property test was performed in accordance with the test method for architectural sealant of JIS A 1439. In the tensile property test, using a Tensilon tester, the stress at 50% elongation (M50, unit: N / mm ² ), the maximum tensile stress (Tmax, unit: N / mm ² ), and the elongation at break (E, unit:%) was measured.

(Coating contamination)
When using the hardened | cured material of the curable composition of this invention as a sealing material, a coating material may be applied on top. Along with the adhesion between the cured product and the paint, it is necessary that the cured product does not deteriorate the curing performance of the paint. The coating film contamination property represents the influence of the cured product on the curing performance of the paint. A curable composition was applied to an aluminum plate in a shape of 50 mm in length, 50 mm in width, and 10 mm in thickness, and cured and cured at 23 ° C. and 50% humidity for 48 hours. A one-component aqueous reaction-curable silicone resin paint (manufactured by Nippon Paint Co., Ltd., trade name: Odefresh Si100II) was applied thereon. Thereafter, after curing at 50 ° C. for 1 week, the sample was left for 1 day under the condition of 23 ° C., then the well-dried contaminated powder was sprinkled on the entire surface and allowed to stand for 10 minutes, and then the contaminated powder that did not adhere was screened off. “◎ (excellent)” indicates that the color of the curable composition is maintained with little adhesion of the contaminated powder, and “A (excellent)” indicates that the color of the curable composition is maintained even though the contaminated powder is slightly adhered. “Good (good)” means that a large amount of contaminating powder is adhered and the color of the curable composition is impaired. In addition, JIS test powders 1 and 8 (Kanto Loam) (manufactured by Japan Powder Industrial Technology Association) were used as contaminated powder.

(durability)
An endurance test was conducted in accordance with JIS A 1439 architectural sealing material test method using aluminum as the adherend. The stretch test was performed 2,000 times or 4,000 times. “X (defect)” indicates that a crack occurred between the adherend and the cured curable composition after the stretch test. “Good (good)” means that no cracks occurred but slight dents occurred. No cracks or dents were generated, and a good one was designated as “◎ (excellent)”.

(Surface stickiness)
A curable composition is applied to a polyethylene terephthalate film in a shape of approximately 150 mm in length, 50 mm in width, and 5 mm in thickness, cured and cured at 23 ° C. and 50% humidity for 8 hours, and the stickiness of the surface is evaluated by touch. did. A sample having no stickiness was designated as “◯ (good)”, and a sticky product was designated as “x (defective)”.

From the results of Table 7, in Examples 51 to 54, in which the curable composition contains the polymer (A) and the polymer (B), the H-type physical properties / tensile properties, the film contamination property, the durability, and the surface stickiness Both were good. Further, in Examples 53 and 54 using the polymers (B-3) and (B-4) having a high molecular weight among the polymers (B), it was particularly difficult for the contaminated powder to adhere to the coating film.
On the other hand, the polymer (A) is not used, and instead, a comparative polymer (C-1) which is not linear but has a number average molecular weight of less than 20,000 and a molecular weight distribution of 1.5. In Examples 55 and 56 used, the elongation (E) is low, the coating film contamination property and the surface stickiness are poor, and the durability is also inferior.
In addition, Example 57 using a comparative polymer (C-2) that does not use the polymer (A) but instead has a linear shape, a number average molecular weight of less than 20,000, and a molecular weight distribution of 1.1 is The elongation (E) was low and the durability was poor.

Claims (10)

A reactive silicon group represented by the following formula (1) is introduced into a precursor polymer (A ′) that is linear, has a polyoxyalkylene chain, and can introduce reactive silicon groups at both ends. a resulting polymer, a number average molecular weight of 20,000 or more state, and are 40,000 or less, the polymer molecular weight distribution Ru der 1.0 to 1.2 (a), and a linear, polyoxy A polymer obtained by introducing a reactive silicon group represented by the following formula (1) into a precursor polymer (B ′) having an alkylene chain and capable of introducing a reactive silicon group at one end: The number average molecular weight is 3,000 or more and 20,000 or less, and among the terminal groups capable of introducing the reactive silicon group of the precursor polymer (B ′), the terminal group substituted with the reactive silicon group The polymer (B) whose ratio is 60 to 100 mol% is contained, and the content of the polymer (A) and the content of the polymer (B) The curable composition whose mass ratio (A / B) of quantity is 95/5-5/95.
-SiX ¹ ₂ R ¹ (1)
[Wherein, R ¹ represents an optionally substituted monovalent organic group having 1 to 20 carbon atoms (excluding a hydrolyzable group), and X ¹ represents a hydroxyl group or a hydrolyzable group. . Two X ¹ may be the same or different from each other. ] The curable composition of Claim 1 which does not contain the following polymer (Z).
Polymer (Z): A polymer having a branched polyoxyalkylene chain and having a reactive silicon group.   The curable composition according to claim 1 or 2, wherein the polymer (B) has a molecular weight distribution (Mw / Mn) of 1.0 to 1.8.   In the polymer (A), the proportion of the terminal group substituted with the reactive silicon group among the terminal groups capable of introducing the reactive silicon group of the precursor polymer (A ′) is 70 to 100 mol%. The curable composition as described in any one of Claims 1-3 which is.   The said precursor polymer (A ') is a precursor polymer (A'1) produced by ring-opening addition polymerization of alkylene oxide to an initiator having two active hydrogens in the presence of a catalyst. The curable composition as described in any one of -4.   The precursor polymer (A ′) was prepared by subjecting an alkylene oxide to a ring-opening addition polymerization to an initiator having two active hydrogens in the presence of a catalyst, and alcoholating the hydroxyl groups of the polymer having both ends hydroxyl groups. -OM (M is an alkali metal), and then is a precursor polymer (A'2) produced by a method of reacting with an unsaturated group-containing halogenated hydrocarbon according to any one of claims 1 to 4. The curable composition as described.   2. The precursor polymer (B′1) produced by ring-opening addition polymerization of alkylene oxide to an initiator having one active hydrogen in the presence of a catalyst in the presence of a catalyst. The curable composition as described in any one of -6.   The precursor polymer (B ′) is produced by alcoholating a hydroxyl group of a polymer having a hydroxyl group at one end, which is produced by ring-opening addition polymerization of alkylene oxide to an initiator having one active hydrogen in the presence of a catalyst. -OM (M is an alkali metal), and then a precursor polymer (B'2) produced by a method of reacting with an unsaturated group-containing halogenated hydrocarbon. The curable composition as described.   The curable composition according to any one of claims 1 to 8, which is used for a sealing material or an adhesive. An initiator having two active hydrogens is subjected to a step of addition polymerization of an alkylene oxide monomer using a zinc hexacyanocobaltate t-butanol complex catalyst, and is linear and has a polyoxyalkylene chain. Obtaining a precursor polymer (A ′) capable of introducing reactive silicon groups at both ends;
  Introducing a reactive silicon group represented by the following formula (1) into the precursor polymer (A ′) to obtain a polymer (A) having a number average molecular weight of 20,000 or more and 40,000 or less; ,
  Precursor polymer having a linear, polyoxyalkylene chain and capable of introducing a reactive silicon group at one end through a step of addition polymerization of an alkylene oxide monomer to an initiator having one active hydrogen Obtaining (B ′);
  A reactive silicon group represented by the following formula (1) is introduced into the precursor polymer (B ′), the number average molecular weight is 3,000 or more and 20,000 or less, and the precursor polymer (B A step of obtaining a polymer (B) in which the proportion of the terminal group substituted with the reactive silicon group in the terminal group capable of introducing the reactive silicon group in ') is 60 to 100 mol%;
  Curable composition which has the process of mixing so that mass ratio (A / B) of content of the said polymer (A) and content of the said polymer (B) may be set to 95 / 5-5 / 95. Manufacturing method.
  -SiX ¹ ₂ R ¹ ... (1)
  [Wherein R ¹ Represents a monovalent organic group having 1 to 20 carbon atoms which may have a substituent (excluding a hydrolyzable group), and X ¹ Represents a hydroxyl group or a hydrolyzable group. 2 X ¹ May be the same as or different from each other. ]