JP2019108492A - Curable composition and cured article - Google Patents

Abstract

To provide a curable composition excellent in storage stability under a high temperature condition.SOLUTION: There is provided a curable composition, containing a polymer having a reactive silicon group, an organic silicon compound represented by (R(CH)SiO)R, and organosilazane represented by (R)SiNHSi(R)with percentage content of the organosilazane of less than 0.2 mass% based on he organic silicon compound. In the formula, Rand Rrepresent saturated or unsaturated monovalent hydrocarbon group having 1 to 4 carbon atoms, Rrepresents a residue excluding a part or all hydroxyl groups from a hydroxyl group-containing compound, and n represents a positive integer.SELECTED DRAWING: None

Description

  The present invention relates to a moisture-curable curable composition containing a polymer having a reactive silicon group and an organic silicon compound, a sealant material, an adhesive and a cured product thereof.

  A polymer having at least one reactive silicon group in the molecule causes hydrolysis of the reactive silicon group by moisture and the like in the air even at room temperature, and forms a siloxane bond to crosslink and form a rubber-like polymer. It is known to have the property that a cured product is obtained.

  Among these polymers having a reactive silicon group, a polymer whose main chain skeleton is polyoxyalkylene, a polymer which is a saturated hydrocarbon, a polyacrylic acid alkyl ester copolymer, and a polymethacrylic acid alkyl ester co-polymer Polymers are already produced industrially and widely used in applications such as sealants, adhesives, paints and the like (for example, Patent Document 1).

  Curable compositions containing these reactive silicon group-containing polymers sometimes suffer from insufficient elongation of the cured product or residual tack on the surface, depending on the compounding and use conditions. In order to solve such problems, a propylene oxide-based polymer having at least one reactive silicon functional group in the molecule, a compound having one silanol group in the molecule, and / or reaction with water are carried out. There is disclosed a curable composition comprising a compound capable of forming a compound having one silanol group in the molecule (Patent Document 2).

Japanese Patent Application Laid-Open No. 05-287187 Japanese Patent Application Laid-Open No. 61-034066

A curable composition comprising a conventional polyoxyalkylene polymer having a reactive silicon group and a compound capable of reacting with a compound having a silanol group in the molecule and / or water to form a compound having a silanol group in the molecule Since the compound of the present invention contains a compound having a silanol group in the molecule by reacting with a compound having a silanol group in the molecule and / or water, the storage stability may be poor such as gelation may occur depending on the storage conditions.
In particular, when the curable composition placed in a storage container in summer is stored in a warehouse without temperature control equipment, the curable composition is exposed to a considerably high temperature. In addition, when transported by ship, it is likely to travel near the equator for several months and be exposed to high temperature conditions for a long time. Conventional curable compositions often have increased viscosity under such conditions, and sufficient storage stability may not be obtained.

In the present invention, even when the curable composition contains a compound having a silanol group in the molecule and / or a compound capable of reacting with water to form a compound having the silanol group in the molecule, the above compound If the content of organosilazane relative to is less than a certain amount, it is found that good storage stability can be obtained by suppressing an increase in viscosity and the like.
An object of the present invention is to provide a curable composition excellent in storage stability with a small change in viscosity even under high temperature storage conditions. The curable composition of the present invention has a small change in viscosity even under storage conditions, particularly at temperatures above 50 ° C. The present invention provides an adhesive and a sealant material containing a curable composition excellent in storage stability even under high temperature storage conditions, and provides a cured product obtained by curing the above-mentioned curable composition.

The present invention is the following [1] to [9].
[1] A curable composition comprising a polymer having a reactive silicon group represented by the following formula 1, an organosilicon compound represented by the following formula 2, and an organosilazane represented by the following formula 3:
The curable composition whose content rate of the said organosilazane is less than 0.2 mass% with respect to the said organosilicon compound.
-SiX _a (R ¹ ) _(3-a) ... Formula 1
[In Formula 1, R ¹ is a monovalent organic group having 1 to 20 carbon atoms and represents an organic group other than a hydrolysable group, X represents a hydroxyl group or a hydrolysable group, and a is 1 to 3] And when a is 1, R ¹ may be the same as or different from each other. When a is 2 or more, X may be the same or different. ]
(R ² (CH ₃ ) ₂ SiO) _n R ³ ... Formula 2
[In Formula 2, R ² represents a saturated or unsaturated monovalent hydrocarbon group having 1 to 4 carbon atoms, and R ³ represents a residue obtained by removing some or all of the hydroxyl groups from the hydroxyl group-containing compound , N represents a positive integer. ].
(R ⁴ ) ₃ SiNHSi (R ⁴ ) ₃ ... Formula 3
[In Formula 3, R ⁴ represents a saturated or unsaturated monovalent hydrocarbon group having 1 to 4 carbon atoms, and may be the same as or different from each other. ].
[2] The main chain skeleton of the polymer having a reactive silicon group is either a polymer having a unit based on an alkylene oxide monomer, an alkyl acrylate ester or a unit based on a methacrylic alkyl ester, or both Curable composition of [1] which is 1 type chosen from the group which consists of a polymer and a saturated hydrocarbon polymer.
[3] The curable composition according to [1] or [2], wherein the polymer having a reactive silicon group includes a polymer having a main chain skeleton having a unit based on an alkylene oxide monomer.
[4] The curable composition of [2] or [3], wherein the molecular weight distribution of the polymer having a unit based on the alkylene oxide monomer is 1.0 to 1.6.
[5] The curable composition according to [1] to [4], wherein the organic silicon compound is either or both of phenyltrimethylsilyl ether and trimethylolpropane tris (trimethylsilyl) ether.
[6] The curable composition of [1] to [5], wherein the organic silicon compound is one in which the organosilazane is reduced.
[7] The curable composition of [1] to [6], wherein the organosilazane is hexamethyldisilazane.
[8] The curable composition of [1] to [7] which is for an adhesive.
[9] The curable composition of [1] to [7], which is for a sealant material.
[10] A cured product obtained by curing the curable composition of [1] to [7].

  ADVANTAGE OF THE INVENTION According to this invention, even when it preserve | saves on high temperature conditions, the curable composition which is small in the change of a viscosity, and is excellent in storage stability can be obtained. According to the present invention, it is possible to obtain a curable composition for an adhesive agent or a sealant material which is excellent in storage stability even under high temperature storage conditions, and to obtain a cured product obtained by curing the above-mentioned curable composition. Can.

  In the present specification and claims, the terms are defined and described as follows.

The (meth) acrylic acid alkyl ester means either or both of an acrylic acid alkyl ester and a methacrylic acid alkyl ester.
The poly (meth) acrylic acid alkyl ester copolymer means a polymer containing a unit based on a (meth) acrylic acid alkyl ester.
The "unit" in the polymer is an atomic group derived from the monomer (i.e., "monomer unit") formed by polymerizing the monomer, and the polymer by processing the polymer. It means a group of atoms in which some of the groups have been converted to another structure.

The number average molecular weight (hereinafter referred to as "Mn") and the weight average molecular weight (hereinafter referred to as "Mw") are determined by gel permeation chromatography (hereinafter referred to as "GPC") based on tetrahydrofuran (hereinafter referred to as "THF"). Is calculated as polystyrene equivalent molecular weight. Molecular weight distribution is the ratio of Mw to Mn.
When the molecular weight of the polymer before reactive silicon group introduction and the molecular weight of the polymer into which reactive silicon group is introduced is compared, the molecular weight of the polymer into which reactive silicon group is introduced usually tends to be slightly larger, but the difference is large There is no.
The numerical range represented by "-" means the numerical range which makes the numerical value before and behind "-" a lower limit and an upper limit.

The present invention comprises a polymer having a reactive silicon group, a specific organosilicon compound and an organosilazane, and the content of the organosilazane is less than 0.2% by mass with respect to the organosilicon compound. It relates to a composition.
<Reactive silicon group>
The reactive silicon group is a group represented by the following formula 1. The reactive silicon group is a group having a hydroxyl group or a hydrolyzable group bonded to a silicon atom and capable of forming a siloxane bond to be crosslinked by a reaction promoted by a curing catalyst. The reactive silicon group is preferably introduced at the main chain terminal of the polymer forming the main chain skeleton.

-SiX _a R ¹ _3-a Formula 1
[Wherein, R ¹ is each independently a monovalent organic group having 1 to 20 carbon atoms, and represents an organic group other than a hydrolysable group, X represents a hydroxyl group or a hydrolysable group, and a is 1 R ¹ may be the same or different from each other when a is 1; When a is 2 or more, X may be the same or different. ]
The a is preferably 1 or 2, and more preferably 2 because the resulting cured product is flexible and has good adhesion.

The R ¹ is preferably at least one selected from the group consisting of an alkyl group, a cycloalkyl group, an aryl group, an α-chloroalkyl group and a triorganosiloxy group. At least one selected from the group consisting of linear or branched alkyl groups having 1 to 4 carbon atoms, cyclohexyl group, phenyl group, benzyl group, α-chloromethyl group, trimethylsiloxy group, triethylsiloxy group and triphenylsiloxy group It is more preferable that A methyl group or an ethyl group is preferable because the balance between the curability and the stability of the polymer having a reactive silicon group is good, and an α-chloromethyl group is preferable because the curing speed of the cured product is fast. Methyl is particularly preferred as it is readily available.

Specifically, the hydrolyzable group of X is a hydrogen atom, a halogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amido group, an acid amide group, an aminooxy group, a mercapto group, an alkenyloxy group It can be mentioned. An alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amido group, an aminooxy group, a mercapto group and an alkenyloxy group are preferable, and an alkoxy group is more preferable because the hydrolysis is mild and easy to handle. As an alkoxy group, a methoxy group, an ethoxy group, and an isopropoxy group are preferable, and a methoxy group or an ethoxy group is more preferable. When X is a methoxy group or an ethoxy group, it is easy to rapidly form a siloxane bond and form a crosslinked structure in the cured product, and the physical property value of the cured product tends to be good.
a is more preferably 2 or 3 from the viewpoint of good reactivity. When a is 2 or 3, X may be the same or different.

In the reactive silicon group, the greater the number of hydrolysable groups bonded to silicon atoms, the higher the reactivity, so the curing rate of the curable composition becomes higher, and the elongation properties of the cured product tend to be degraded. . In particular, the tendency tends to be remarkable as the number of hydrolyzable groups bonded to the same silicon atom increases.
It is also possible to introduce different types of reactive silicon groups into one molecule of polymer. The kind and introduction ratio of the reactive silicon group to be introduced can be appropriately determined so as to obtain a desired elongation property and a curing rate in the cured product.
Specific examples of the reactive silicon group include trimethoxysilyl group, triethoxysilyl group, triisopropoxysilyl group, dimethoxymethylsilyl group, diethoxymethylsilyl group, diisopropoxymethylsilyl group, methoxydimethylsilyl group, ethoxy A dimethyl silyl group, the (alpha)-chloromethyl dimethoxy silyl group, and the (alpha)-chloromethyl diethoxy silyl group are mentioned. A trimethoxysilyl group, a triethoxysilyl group, and a dimethoxymethylsilyl group are preferable, and a trimethoxysilyl group is more preferable, because they have high activity and good curability can be obtained. The dimethoxymethyl silyl group tends to have good storage stability, and the triethoxy silyl group tends to be highly safe because the alcohol produced along with the hydrolysis reaction of the reactive silicon group is ethanol.
The method for obtaining a polymer having a reactive silicon group is, for example, reacting a polymer having a hydroxyl group in the molecule with an organic compound having a group having reactivity with the above hydroxyl group and an unsaturated group, A conventionally known method can be used, such as a method of obtaining a polymer containing and then reacting the hydrosilane compound having a reactive silicon group to effect hydrosilylation.

<Polymer Having Reactive Silicon Group>
The polymer having a reactive silicon group in the curable composition of the present invention is not particularly limited, and one having a polymer containing units based on various monomers as a main chain skeleton can be used.
Examples of the main chain skeleton include polyoxyalkylene polymers described later, saturated hydrocarbon polymers described later, poly (meth) acrylic acid alkyl ester polymers described below, polyester polymers, polysulfide polymers, polyamide polymers, Polycarbonate polymers and diallyl phthalate polymers are exemplified.
As the main chain skeleton of the polymer having a reactive silicon group, the balance of the elongation properties, modulus, weather resistance and the like in the cured product of the curable composition can be easily adjusted, so the polyoxyalkylene polymer described later, poly described later At least one selected from the group consisting of (meth) acrylic acid alkyl ester polymers and the above-mentioned saturated hydrocarbon polymers is preferred. In order to be excellent in adhesiveness and weather resistance, either one or both of the below-mentioned polyoxyalkylene polymer or the below-mentioned (meth) acrylic acid alkyl ester polymer is more preferable.
(Polyoxyalkylene polymer)
The polymer having a reactive silicon group is a polymer whose main chain skeleton has a unit based on an alkylene oxide monomer (hereinafter, referred to as "polyoxyalkylene polymer") (hereinafter, "reactive silicon" Group is referred to as "polyoxyalkylene polymer having a group".
A polyoxyalkylene polymer having a reactive silicon group can be produced by a conventionally known method, and can be obtained by introducing the above-mentioned reactive silicon group into a hydroxyl group-containing polyoxyalkylene polymer.

The polyoxyalkylene polymer is preferably obtained by reacting a cyclic ether in the presence of a catalyst using a compound containing active hydrogen which can react with the cyclic ether as an initiator. The active hydrogen is preferably hydrogen based on a hydroxyl group.
Examples of the initiator include compounds exemplified below or compounds obtained by adding a small amount of cyclic ether to the compounds. The compounds exemplified below may be one kind or a mixture of two or more kinds.
As the initiator, monools or polyhydric alcohols are preferable, and polyhydric alcohols are more preferable in that the elongation property of the cured product is good.
As monools, alcohols or alkanolamines having 1 to 6 carbon atoms are preferable, and methanol, ethanol, proparel, butanol, monoethanolamine are more preferable in that the viscosity of the curable composition can be lowered, and methanol or More preferred is butanol.
Examples of polyhydric alcohols include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, tripropylene glycol, 1,2-butanediol, 1,4-butanediol, 1,6-hexanediol, glycerin and trimethylolpropane. 1,2,6-hexanetriol, pentaerythritol, diglycerin, tetramethylol cyclohexane, sorbitol, mannitol, diethanolamine, triethanolamine, isopropanolamine. Ethylene glycol, propylene glycol, glycerin, pentaerythritol or sorbitol is preferable, and ethylene glycol, propylene glycol, and glycerol are more preferable in that the elongation property of the cured product is good.

The cyclic ether is preferably a 3- to 6-membered cyclic ether compound having one oxygen atom in the ring. Ethylene oxide (hereinafter referred to as "EO"), propylene oxide (hereinafter referred to as "PO") or butylene oxide is more preferable, and EO, PO, or a combination of EO and PO is more preferable. When it is used for a sealant material or an adhesive, it is preferable to contain PO because it is amorphous and has a relatively low viscosity.
The cyclic ether may be used alone or in combination of two or more. When using 2 or more types together, they may be mixed and made to react, or you may make it react sequentially.

The polyoxyalkylene polymer in the polyoxyalkylene polymer having a reactive silicon group is, for example, a polymerization method using an alkali catalyst such as KOH, a transition such as a complex obtained by reacting an organoaluminum compound and porphyrin It can be manufactured by a conventionally known method such as a polymerization method using a metal compound-porphyrin complex catalyst, a polymerization method using a composite metal cyanide complex catalyst, and a polymerization method using a catalyst comprising a phosphazene compound.
When a composite metal cyanide complex catalyst is used, the molecular weight distribution of the resulting polymer can be narrowed, and a curable composition having a low viscosity is easily obtained, which is preferable.
The composite metal cyanide complex catalyst is preferably one in which an organic ligand is coordinated to a reaction product obtained by reacting a metal halide and an alkali metal cyanometalate. As the organic ligand, at least one compound selected from the group consisting of alcohol, ether, ketone, ester, amine and amide is preferable, and from the viewpoint of being able to narrow the molecular weight distribution, one containing t-butyl alcohol is preferable. More preferred is t-butyl alcohol. When a composite metal cyanide complex catalyst in which t-butyl alcohol is coordinated is used, a polymer having a molecular weight distribution of 1.01 to 1.4 tends to be obtained.

  For example, JP-B-45-36319, JP-A-50-156599, JP-A-61-197631, JP-A-3-72527, and JP-A-Hei. The methods proposed in the respective publications, such as 8-231707, U.S. Pat. No. 3,632,557, U.S. Pat.

  The number of reactive silicon groups introduced per molecule of the polyoxyalkylene polymer having a reactive silicon group is preferably 0.8 or more, more preferably 1 or more, and 1. More preferably, it is two or more. The larger the number of reactive silicon groups, the better the curability and the less the stickiness occurs in the cured product.

3,000-100,000 are preferable, as for Mn of the polyoxyalkylene polymer containing a reactive silicon group, 4,000-50,000 are more preferable, and 5,000-40,000 are more preferable. Within the above range, the curability of the cured product is likely to be good, and the elongation properties of the resulting cured product are likely to be good.
The Mw / Mn of the reactive silicon group-containing polyoxyalkylene polymer is preferably 1.0 to 1.6, more preferably 1.01 to 1.4, and still more preferably 1.02 to 1.3. Within the above range, the curability of the cured product is likely to be good, and the elongation properties of the resulting cured product are likely to be good.
The polyoxyalkylene polymer having a reactive silicon group may be used alone or in combination of two or more.

(Poly (meth) acrylic acid alkyl ester copolymer having a reactive silicon group)
The polymer having a reactive silicon group may include a poly (meth) acrylic acid alkyl ester copolymer in which the main chain skeleton has a unit based on a (meth) acrylic acid alkyl ester monomer (hereinafter referred to as “ “Poly (meth) acrylic acid alkyl ester copolymer having a reactive silicon group”
The poly (meth) acrylic acid alkyl ester copolymer is a polymer having a unit based on a (meth) acrylic acid alkyl ester monomer.
About the said (meth) acrylic-acid alkylester monomer, the polymerization method of this monomer, and the introduction method of the reactive silicon group to a copolymer, Unexamined-Japanese-Patent 2002-179904, Unexamined-Japanese-Patent 2011-94160 The monomers, polymerization method and introduction method of reactive silicon group described in can be used.
As said (meth) acrylic-acid alkylester monomer, the carbon number of the alkyl group is 1 to 8 (meth) acrylic-acid alkylester monomer, and the carbon number of the alkyl group is 10 or more. Those having both of the ester monomers are preferred.
As the (meth) acrylic acid alkyl ester monomer having 1 to 8 carbon atoms of alkyl group, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, (meth) acrylic acid Isopropyl acid, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate 2-ethylhexyl (meth) acrylate is preferable, and methyl (meth) acrylate, n-butyl (meth) acrylate, cyclohexyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate are more preferable.
As the (meth) acrylic acid alkyl ester monomer having 10 or more carbon atoms, a (meth) acrylic acid alkyl ester monomer having 10 to 22 carbon atoms is preferable, and (meth) acrylic acid dodecyl, (meth) acrylic acid Hexadecyl acid, octadecyl (meth) acrylate and docosyl (meth) acrylate are more preferable, and dodecyl (meth) acrylate and octadecyl (meth) acrylate are more preferable.
When the (meth) acrylic acid alkyl ester monomer having 1 to 8 carbon atoms in the alkyl group and the (meth) acrylic acid alkyl ester monomer having 10 or more carbon atoms in the alkyl group are used in combination, the ratio is particularly limited Although not preferred, the weight ratio of the former to the latter is preferably 95/5 to 40/60, more preferably 90/10 to 50/50.
As a method for introducing a reactive silicon group into a copolymer, the method described in the above-mentioned document can be used without particular limitation, but when polymerizing the (meth) acrylic acid alkyl ester monomer, formula 1 is used. The method of using together the unsaturated group containing monomer which has the reactive silicon group represented is preferable.
Examples of the unsaturated group-containing monomer having a reactive silicon group represented by the above formula 1 include vinylsilane and (meth) acrylic acid silyl ester.
Examples of vinylsilanes include vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinyltrimethoxysilane and vinyltriethoxysilane.
As (meth) acrylic acid silyl ester, (meth) acrylic acid-3- (methyldimethoxysilyl) propyl, (meth) acrylic acid-3- (trimethoxysilyl) propyl, (meth) acrylic acid-3- (methyl) Diethoxy silyl) propyl and (meth) acrylic acid 3- (triethoxy silyl) propyl are mentioned.

  Since the tensile strength of the cured product of the resulting copolymer is good, a copolymer comprising a styrene monomer and a (meth) acrylic acid alkyl ester monomer or an acrylic acid alkyl ester monomer and an alkyl methacrylate A poly (meth) acrylic acid alkyl ester copolymer consisting of at least one or both of ester monomers is preferred, and a copolymer consisting of a styrene monomer and an acrylic acid alkyl ester monomer or an acrylic acid alkyl ester monomer The polyacrylic acid alkyl ester copolymer which consists of these is more preferable.

  As a process for producing the poly (meth) acrylic acid alkyl ester copolymer having the reactive silicon group, bulk polymerization, solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization, etc. are not particularly limited and known methods may be used. Can. For example, the free radical polymerization method using a chain transfer agent described in JP-B-3-14068, JP-B-4-55444 or JP-A-6-211922, JP-A-9-272714, Matyjaszewski et al. Journal of American Chemical Society (J. Am. Chem. Soc.) 1995, 117, 5614, and the atom transfer radical described in JP 2011-94160 A, JP 2012-31423 A Living radical polymerization method can be used.

  The molecular weight distribution of the poly (meth) acrylic acid alkyl ester copolymer having a reactive silicon group can be controlled by the polymerization conditions such as the type of initiator and the polymerization temperature. A polymer obtained by a conventional free radical polymerization method using an azo compound, a peroxide or the like as a polymerization initiator tends to have a large molecular weight distribution. The polymer obtained by the living radical polymerization method tends to have a small molecular weight distribution.

The said monomer which comprises the poly (meth) acrylic-acid alkylester copolymer which has the said reactive silicon group may superpose | polymerize in presence of the polyoxyalkylene polymer which has a reactive silicon group. In this case, the dispersibility of the poly (meth) acrylic acid alkyl ester copolymer having a reactive silicon group in the curable composition is likely to be improved. In the presence of components of a curable composition other than a reactive silicon group-containing polyoxyalkylene polymer, the above-mentioned monomers constituting a poly (meth) acrylic acid alkyl ester copolymer having a reactive silicon group It may be polymerized or may be polymerized in the absence of the components of the curable composition. Furthermore, the obtained poly (meth) acrylic acid alkyl ester copolymer having a reactive silicon group may be mixed with the polyoxyalkylene polymer having a reactive silicon group.
A commercially available polymer can also be used for the poly (meth) acrylic acid alkyl ester copolymer which has the said reactive silicon group. As a commercially available (meth) acrylic acid alkyl ester copolymer, for example, XMAP S type (for example, SA100S, SA110S, SA310S, OR100S, all are product names of Kaneka Corporation), Alfone (for example, US-6170, US-6190) All of which are product names of Toa Gosei Co., Ltd. and Actflow (NE-1000 and NE-3000, both of which are product names of SOKEN CHEMICAL CO., LTD.).

  The average number of reactive silicon groups per polymer chain of the poly (meth) acrylic acid alkyl ester copolymer having the reactive silicon group is preferably 0.05 to 5, and 0.1 to 3 The number is more preferably 0.1 to 2. Within the above range, the crosslink density of the cured product is easily obtained, and the breaking strength tends to be good.

The Mn of the poly (meth) acrylic acid alkyl ester copolymer having the reactive silicon group is preferably 3,000 to 100,000, more preferably 4,000 to 50,000, and 5,000 to 40,000. More preferable. It is preferable at the point which is excellent in the elongation and weather resistance of hardened | cured material being in the said range.
1.0-6 are preferable, as Mw / Mn of the poly (meth) acrylic-acid alkylester copolymer which has the said reactive silicon group, 1.01-4 are more preferable, and 1.02-3 are more preferable. It is preferable at the point which is excellent in the elongation and weather resistance of hardened | cured material being in the said range.
The poly (meth) acrylic acid alkyl ester copolymer having a reactive silicon group may be used alone or in combination of two or more.

(Saturated hydrocarbon polymer having a reactive silicon group)
The polymer having a reactive silicon group may contain a polymer whose main chain skeleton is a saturated hydrocarbon polymer. When the main chain skeleton is a saturated hydrocarbon polymer, it tends to be excellent in heat resistance, weather resistance, durability, and moisture blocking property.
The above-mentioned saturated hydrocarbon polymer is preferably a polymer having a unit based on an olefin compound having 2 to 6 carbon atoms, or a polymer having a unit based on a diene compound.
Ethylene, propylene, 1-butene, and isobutylene can be illustrated as said C2-C6 olefin compound. Examples of the diene compound include butadiene, isoprene and chloroprene. The saturated hydrocarbon polymer may have units based on acrylonitrile and styrene, in addition to the above compounds.
As the above-mentioned saturated hydrocarbon polymer, a polymer consisting of only a monomer based on isobutylene, a polymer consisting only of a monomer based on butadiene, a polymer consisting only of a monomer based on isoprene, a monomer based on chloroprene Polymers consisting only of a body, polymers having units based on ethylene and propylene, polymers having units based on isobutylene and isoprene, polymers having units based on isoprene and acrylonitrile, polymers having units based on isoprene and styrene , Polymers having units based on butadiene and acrylonitrile, polymers having units based on butadiene and styrene, polymers having units based on isoprene, acrylonitrile and styrene, monomers based on butadiene, acrylonitrile and styrene Polymer can be exemplified with.
The saturated hydrocarbon polymer may be a polymer obtained by hydrogenating after obtaining a polymer having a unit based on the olefin compound (hereinafter, referred to as “hydrogenated olefin polymer”).
As the hydrogenated olefin polymer, a polymer obtained by obtaining a polymer having a unit based on isobutylene and then hydrogenated, or a polymer obtained by obtaining a polymer having a unit based on butadiene and then hydrogenated can be exemplified.

The polymer having a unit based on isobutylene may be formed only from a unit based on isobutylene or may be a copolymer having a unit based on a monomer other than isobutylene; From the aspect, one containing 50 mass% or more of a unit based on isobutylene is preferable, one containing 80 mass% or more is more preferable, and one containing 90 to 99 mass% is more preferable.
As the above-mentioned saturated hydrocarbon polymer, a hydrogenated olefin polymer is preferable because it is easy to introduce a functional group at the terminal, easy to control the molecular weight, and can increase the number of terminal functional groups, and is based on isobutylene After obtaining a polymer having a unit, a hydrogenated polymer or a polymer having a unit based on butadiene is preferably obtained and then a hydrogenated polymer is more preferable, and a polymer having a unit based on isobutylene is obtained by living cationic polymerization. Further preferred is a hydrogenated polymer.

Various known polymerization methods can be used as a synthesis method of the saturated hydrocarbon polymer having a reactive silicon group.
Examples of the process for producing the saturated hydrocarbon polymer having a reactive silicon group include, for example, JP-B-4-69659, JP-B-7-108928, JP-A-63-254149, JP-A-64-22904, The methods described in the disclosures of JP-A-1-197509, Patent Publication No. 2539445, Patent Publication No. 2873395, and JP-A-7-53882 can be used without particular limitation.
The number of reactive silicon groups introduced per molecule of the saturated hydrocarbon polymer having a reactive silicon group is preferably 0.8 or more, and more preferably 1 or more. It is more preferable that it is .2 or more. The larger the number of reactive silicon groups, the better the curability and the less the stickiness occurs in the cured product.

3,000-100,000 are preferable, as for Mn of the saturated hydrocarbon polymer which has the said reactive silicon group, 4,000-50,000 are more preferable, and 5,000-40,000 are more preferable. Within the above range, the curability of the cured product is likely to be good, and the elongation properties of the resulting cured product are likely to be good.
1-6 are preferable, as Mw / Mn of the saturated hydrocarbon polymer which has the said reactive silicon group, 1.01-4 are more preferable, and 1.02-3 are more preferable. Within the above range, the curability of the cured product is likely to be good, and the elongation properties of the resulting cured product are likely to be good.
The saturated hydrocarbon polymer having a reactive silicon group may be used alone or in combination of two or more.

(Polymer having a reactive silicon group)
The above-mentioned polymer having a reactive silicon group may be used alone or in combination of two or more. Specifically, from the group consisting of a polyoxyalkylene polymer having a reactive silicon group, a poly (meth) acrylic acid alkyl ester copolymer having a reactive silicon group, and a saturated hydrocarbon polymer having a reactive silicon group One or more selected can be used.
When the polyoxyalkylene polymer having a reactive silicon group is contained, the content of the polyoxyalkylene polymer having a reactive silicon group is 20 to 100 mass with respect to 100 parts by mass of the polymer having a reactive silicon group. A part is preferable and 30-80 mass parts is more preferable. Within the above range, a curable composition having a low viscosity is easily obtained, and a cured product having good elongation is easily obtained.
When it contains a poly (meth) acrylic acid alkyl ester copolymer having a reactive silicon group, a poly (meth) acrylic acid alkyl ester having a reactive silicon group to 100 parts by mass of the polymer having a reactive silicon group 10-80 mass parts is preferable, and, as for content of a copolymer, 20-70 mass parts is more preferable. If the content is in the above range, the weather resistance tends to be good.
In the case of containing a saturated hydrocarbon polymer having a reactive silicon group, the content of the saturated hydrocarbon polymer having a reactive silicon group is 5 to 70 mass with respect to 100 parts by mass of the polymer having a reactive silicon group. Part is preferable and 10 to 50 parts by mass is more preferable. The intensity | strength of hardened | cured material tends to become high as it is in the said range.

  The number of reactive silicon groups introduced into one molecule of polymer in the polymer having a reactive silicon group is preferably at least 0.8 or more on average, more preferably one or more. And 1.2 or more are more preferable. When the number of reactive silicon groups contained in one molecule of the polymer is within the above range, good curability is easily obtained, and good elongation property is easily expressed. The number of reactive silicon groups introduced into one polymer molecule in the polymer having a reactive silicon group is a mixture of the entire Mn of the polymer having a reactive silicon group and the polymer having a reactive silicon group And the value of the number of reactive silicon groups per 1 g of the polymer obtained from the NMR measurement of

The total Mn of the polymer having a reactive silicon group is 3,000 or more and 100,000 or less, more preferably 4,000 or more and 50,000 or less, and still more preferably 5,000 or more and 40,000 or less is there. If Mn is in the above range, good elongation characteristics of the cured product can be easily obtained, and the viscosity can be easily adjusted. The total Mn of the polymer having a reactive silicon group is a value obtained by analyzing all GPC charts of the polymer having a reactive silicon group.
1.0-6 are preferable, as for the molecular weight distribution of the whole polymer which has a reactive silicon group, 1.01-4 are more preferable, and 1.02-3 are more preferable. If the molecular weight distribution is in the above range, the viscosity of the curable composition tends to be low, and the workability tends to be good. The overall molecular weight distribution of the polymer having a reactive silicon group is a value obtained by analyzing all the GPC charts of the polymer having a reactive silicon group.

<Organic silicon compound>
The curable composition of the present invention comprises the polymer having the reactive silicon group, the organosilicon compound represented by the following formula 2, and an organosilazane, and the content of the organosilazane is relative to the organosilicon compound. It is less than 0.2% by mass. The organic silicon compound is a compound that generates silanol by reaction.
(R ² (CH ₃ ) ₂ SiO) _n R ³ ... Formula 2
[Wherein, R ² represents a saturated or unsaturated monovalent hydrocarbon group having 1 to 4 carbon atoms. R ³ represents a residue obtained by removing some or all of the hydroxyl groups from the hydroxyl group-containing compound. n is a positive integer. ].
R ² is preferably a methyl group, an ethyl group, an isopropyl group or a vinyl group, and a methyl group is more preferable since it is easily available.
Examples of the hydroxyl group-containing compound which can be a residue obtained by removing some or all of the hydroxyl groups from the hydroxyl group-containing compound of R ³ include, for example, methanol, ethanol, normal butanol, isobutal, normal pentanol, isopentanol, benzyl alcohol, Alcohols having 30 or less carbon atoms such as cyclohexanol, 2-chloroethanol, 2-chloropropanol, ethylene glycol, propanediol, propylene glycol, butanediol, glycerin, trimethylolpropane, etc .; phenol, cresol, chlorphenol, bisphenol A, A C6-C30 substituted or unsubstituted aromatic hydroxy compound, such as a naphthol, a hydroquinone, a hydronaphthoquinone, etc. are mentioned. Phenol, propylene glycol, glycerin and trimethylolpropane are preferable, and phenol and trimethylolpropane are more preferable because the reaction rate with the polymer having a reactive silicon group is appropriate.
The compound that can be R ³ preferably does not contain a hetero atom other than oxygen and a halogen atom, and is a compound having a substituted or unsubstituted phenyl group in order to be easily available and to exert a preferable effect.
Examples of the organic silicon compound include CH ₃ OSi (CH ₃ ) ₃ , CH ₃ CH ₂ OSi (CH ₃ ) ₃ , CH ₃ CH (CH ₃ ) OSi (CH ₃ ) ₃ , and CH ₃ CHClCH ₂ OSi (CH ₃ ). ₃ ) ₃ , ClCH ₂ CH ₂ OSi (CH ₃ ) ₃ , C ₆ H ₅ OSi (CH ₃ ) ₃ (trimethylphenoxysilane, hereinafter referred to as “PTMS”), m-CH ₃ C ₆ H ₄ OSi (CH ₃ ) _{3) 3, m-ClC 6} H 4 OSi (CH 3) 3, (CH 3) 3 SiOCH 2 CH 2 OSi (CH 3) 3, (CH 3) 3 SiOCH 2 CH (CH 3) OSi (CH 3) _{3, (CH 3) 3 SiOCH} 2 CH 2 OSi (CH 3) 3, (CH 3) 3 SiOCH 2 CH 2 OCH 2 CH 2 OSi (CH _{) 3, (CH 3) 3} SiO (CH 2 CH (CH 3) O) 2 Si (CH 3) 3, (CH 3) 3 SiO (CH 2 CH 2 O) 3 Si (CH 3) 3, (CH _{3) 3 SiO (CH 2 CH} (CH 3) O) 3 Si (CH 3) 3, (CH 3) 3 SiO (CH 2 CH (OSi (CH 3) 3) CH 2) OSi (CH 3) 3, _{((CH 3) 3 SiOCH 2} ) 3 CCH 2 CH 3 ( trimethylolpropane tris (trimethylsilyl) ether. hereinafter referred to as _{"TMP-3TMS".), (CH 3) 3} SiOCH 2 CH 2 OCH 2 CH 2 CH 3 _{, (CH 3) 3 SiO (} CH 2) 4 OSi (CH 3) 3, p- (CH 3) 3 SiOC 6 H 4 OSi (CH 3) 3, ClCH 2 CH 2 (OSi ( _{H 3) 2 CH = CH 2} ), include _{(CH 2 = CH (CH 3} ) 2 SiO) (CH 2) 2 (OSi (CH 3) 2 CH = CH 2).
140 or more are preferable and, as for the formula weight of the said organic silicon compound, 150 or more are more preferable from the point of improvement of a modulus or elongation. The amount of formula of the organosilicon compound is preferably 5,000 or less, and 2,000 or less is preferable from the viewpoint of improving modulus and elongation.
One or both of PTMS and TMP-3TMS are more preferable because they are easily available.
When PTMS and TMP-3TMS are contained, the mass ratio of PTMS to TMP-3TMS is preferably 20/80 to 80/20, and more preferably 30/70 to 70/30. When the mass ratio of the two contents is within the above range, good curability and the effect of improving the repeated stretch durability of the cured product can be obtained in a well-balanced manner, and although the elastic modulus is relatively high, It is easy to obtain a cured product having good repeated stretch durability.

  The ratio of the total amount of PTMS and TMP-3TMS to the total amount of the organic silicon compound contained in the curable composition is preferably 60% by mass or more, more preferably 80% by mass or more, and further 100% by mass preferable.

<Organo silazane>
Organosilazane in the present invention is represented by Formula 3.
(R ⁴ ) ₃ SiNHSi (R ⁴ ) ₃ ... Formula 3
[Wherein, R ⁴ represents a saturated or unsaturated monovalent hydrocarbon group having 1 to 4 carbon atoms, which may be the same as or different from each other. ].
The R ^4, preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, further preferably a methyl group. R ⁴ is preferably identical, more preferably all are ethyl or methyl, and even more preferably all methyl.
The organosilazane is one of the raw materials for producing the organic silicon compound. In the conventional organic silicon compounds, the organosilazane used in the production process often remains. For example, when producing PTMS or TMP-3TMS, in the step of reacting phenol or trimethylolpropane as a raw material with chlorotrimethylsilane, neutralization of hydrochloric acid generated in the reaction and introduction of a trimethylsilyl group into phenol or trimethylolpropane as a raw material Organosilazanes such as hexamethyldisilazane are added for this purpose. The amount of the hexamethyldisilazane added is at least 1.1 molar equivalent relative to chlorotrimethylsilane in order to accelerate the reaction. Therefore, in the system after the reaction, hexamethyldisilazane which was not used in the reaction sometimes remained at about several mass% with respect to PTMS or TMP-3TMS.
In the present invention, in the case of a curable composition having a certain amount of organosilazane or less, thickening does not easily occur even under high temperature conditions severer than in the prior art, and storage stability is good, and the obtained cured product It was found that the elongation properties of were good.
As the organosilazane, hexamethyldisilazane and hexaethyldisilazane are preferable because they have high reactivity when producing an organic silicon compound, and hexamethyldisilazane is more preferable because they are easily available.
The organic silicon compound in the present invention is preferably one in which the content of organosilazane contained in the organic silicon compound is reduced.
As a method of reducing the organosilazane contained in the above organic silicon compound, for example, after adding an acid to make a salt, a method of extracting to the aqueous phase by oil-water separation, organosilazane having a low boiling point by vacuum degassing The method of distilling is mentioned. Since the yield is good, a method of distillation under reduced pressure degassing is preferred.
The content of the organosilazane can be quantified by an internal standard method by gas chromatography, and the following content can be calculated using the quantified value.
The content of the organosilazane is less than 0.2% by mass with respect to the organic silicon compound, preferably as low as possible, and 0.1% by mass or less is more preferable, and is not detected in the analysis by the following gas chromatography More preferable.

<Curable composition>
The curable composition of the present invention contains the polymer having the above reactive silicon group, the above organosilicon compound, and less than 0.2% by mass of organosilazane with respect to the above organosilicon compound.
The content of the polymer having a reactive silicon group in the curable composition is preferably 10 to 30 parts by mass, and more preferably 15 to 25 parts by mass with respect to 100 parts by mass of the curable composition. When the content of the polymer having a reactive silicon group is in the above range, the elongation and the strength of the cured product are likely to be good.
The total content of the organic silicon compound in the curable composition can be appropriately selected in accordance with the physical properties expected for the cured product, but 0.1 to 10 parts by mass relative to 100 parts by mass of the polymer having a reactive silicon group Preferably, 0.5 to 5 parts by mass is more preferable. When the content of the organic silicon compound is at least the lower limit value of the above range, the stickiness of the surface of the cured product is easily prevented. Favorable curability is easy to be obtained as it is below the upper limit of the said range.
The content of organosilazane in the curable composition is preferably less than 20 ppm, more preferably 10 ppm or less, and still more preferably not contained relative to 100 parts by mass of the polymer having a reactive silicon group. It is hard to be thickened even if it preserve | saves a curable composition at high temperature as it is in the said range, and storage stability tends to become favorable.
The content of organosilazane in the curable composition can be quantified by an internal standard method by gas chromatography.
A curable composition is obtained by mixing an organosilicon compound in which the content of organosilazane is reduced by the method of reducing the content of organosilazane contained in the above organosilicon compound with the polymer having a reactive silicon group. Is preferably obtained.
As a method of mixing the polymer having a reactive silicon group and the organic silicon compound, the conditions may be adjusted according to the properties of the organic silicon compound, and it may be uniformly dissolved and dispersed. At this time, it is not necessary to be in a completely uniform state, and even in an opaque state, it may be dispersed almost uniformly. Also, if necessary, a dispersibility improver such as a surfactant may be used in combination.
The organic silicon compound hydrolyzes to form a silanol compound when the curable composition cures, and reacts with the reactive silicon group or the hydrolyzed group in the polymer having a reactive silicon group. When organosilazane is contained in an amount of 0.2% by mass or more with respect to the organic silicon compound, the pH of the curable composition becomes high, and hydrolysis easily occurs, so that the curable composition is multimerized and thickened. When the content of organosilazane is less than 0.2% by mass with respect to the organic silicon compound, the pH of the curable composition becomes near neutral and hydrolysis is suppressed, so that the curable composition can be stored even under high temperature storage conditions. Can be prevented.

The curable composition of the present invention can optionally contain known components in the curable composition. Specifically, curing catalysts, cocatalysts, fillers, thixotropic agents, stabilizers, adhesiveness imparting agents, flame retardants, curing regulators, radical inhibitors, metal deactivators, antiozonants, phosphorus Additives such as peroxide peroxide decomposition agents, lubricants, pigments, foaming agents, solvents, fungicides and the like can be mentioned. The curable composition may contain one or more of these various additives.
The method for preparing a curable composition containing such additive components is not particularly limited, and the additive components may be added all at once or several times during or after the production of the curable composition. It may be divided and added.

As a curing catalyst, 1 or more types of a curing catalyst as described in stage of Unexamined-Japanese-Patent No. 2011-178955 can be used. 0.01-15.0 mass parts is preferable with respect to a total of 100 mass parts of a polymer which has a reactive silicon group, and, as for content of a curing catalyst, 0.1-10 mass parts is more preferable. The curing reaction easily proceeds sufficiently when the content is at least the lower limit value of the above range, and no heat generation or foaming occurs locally at the curing when the content is no less than the upper limit value, and a good cured product is easily obtained.
As a cocatalyst, one or more of the cocatalysts described in WO 16/031913 can be used. As the co-catalyst, an amine, a carboxylic acid or a phosphoric acid is preferable, and an amine is more preferable, because the curing speed of the curable composition is fast and good mechanical properties of the cured product can be obtained. 0.01-15 mass parts is preferable with respect to a total of 100 mass parts of the polymer which has a reactive silicon group, and, as for content of a promoter, 0.1-5 mass parts is especially preferable. The curing reaction easily proceeds sufficiently when the content is at least the lower limit value of the above range, and no heat generation or foaming occurs locally at the curing when the content is no less than the upper limit value, and a good cured product is easily obtained.

As a filler, 1 or more types of the filler as described in stage of Unexamined-Japanese-Patent No. 2011-178955 can be used. The content of the filler is preferably 1 to 1,000 parts by mass, more preferably 10 to 400 parts by mass, and further preferably 50 to 300 parts by mass with respect to a total of 100 parts by mass of the polymer having a reactive silicon group. preferable.
As the thixotropic agent, one or more of the thixotropic agents described in paragraph [0086] of JP-A-2011-111525 can be used. The content of the thixotropic agent is preferably 0.1 to 20 parts by mass with respect to 100 parts by mass in total of the polymer having a reactive silicon group.

Examples of the stabilizer include antioxidants, light stabilizers, and ultraviolet light absorbers, and specific examples thereof include those described in paragraphs [0087] to [0090] of JP-A-2011-111525. One or more can be used.
The stabilizer may be used alone or in combination of two or more. In particular, by combining two or more of an antioxidant, a light stabilizer, and an ultraviolet light absorber, it is possible to improve the overall stability by taking advantage of the respective features.
The content in the case of containing an antioxidant, a light stabilizer or an ultraviolet light absorber is preferably 0.1 to 10 parts by mass with respect to a total of 100 parts by mass of the polymer having a reactive silicon group in each, 0.2 -5 mass parts are more preferable.

As an adhesion imparting agent, organosilane coupling agents such as a silane having a (meth) acryloyloxy group, a silane having an amino group, a silane having an epoxy group, and a silane having a carboxy group; isopropyltri (N-aminoethyl- Organometallic coupling agents such as aminoethyl) propyltrimethoxytitanate, 3-mercaptopropyltrimethoxitanate, etc .; compounds having an epoxy group. These may be used alone or in combination of two or more.
The content of the organic silane coupling agent and the organic metal coupling agent is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass in total of the polymer having a reactive silicon group in each.
As a compound which has an epoxy group, the compound as described in stage-of Unexamined-Japanese-Patent No. 2014-227427 is mentioned. The compound having an epoxy group is a compound having one or more epoxy groups in one molecule, and examples thereof include an epoxy resin and an epoxy group-containing silicon compound. From the viewpoint of balance of curability, adhesive strength, adherend versatility, water resistance, durability and workability, a bisphenol A epoxy resin or an epoxy group-containing silicon compound is preferable.
100 mass parts or less are preferable with respect to a total of 100 mass parts of the polymer which has a reactive silicon group, and, as for content of an epoxy resin, 5-80 mass parts is more preferable.
<Industrial applicability>
The curable composition of the present invention is a sealant material / adhesive agent (elastic sealant material for construction, sealant material for double glazing, etc.), sealant (anticorrosive / waterproof sealant for glass end, solar cell) Backside sealants, etc.), Sealants (Building sealants, marine sealants, automotive sealants, road sealants etc.), electric insulating materials (insulation coatings for electric wires and cables.) Are preferably used. In particular, it is suitable for applications requiring restorability, elongation properties, and repeated stretch durability, such as a sealant material applied outdoors such as a building outer wall, following expansion and contraction of the outer wall.

The present invention will be specifically described below, but the present invention is not limited to these examples. Examples 1, 2, 4 and 5 are examples and examples 3 and 6 are comparative examples.
(Storage stability test)
The prepared curable composition was stored at a temperature of 80 ° C. for 28 days. The viscosity of the curable composition before and after storage was measured with an E-type viscometer calibrated with a standard solution. The measurement conditions were a temperature of 25 ° C. and a rotation speed of 20 rpm.
(Quantification of hexamethyldisilazane)
Hexane was added to 10 g of the organic silicon compound and 0.1 g of ethylbenzene to adjust to 100 g, and the mixture was stirred to obtain a sample solution. The amount of hexamethylenedisilazane in the organosilicon compound was quantified by gas chromatography of the obtained sample solution. For the determination, a calibration curve obtained from the concentration ratio of hexamethyldisilazane and ethylbenzene with known concentrations and the area ratio of gas chromatography was used.
The measurement conditions for gas chromatography are as follows: DB-1 (film thickness: 0.25 μm, inner diameter: 0.25 mm, length: 30 m) is used as the column, helium inert gas, linear velocity 25.0 cm / sec (100 ° C.) ), The split ratio was 50. The temperature conditions of the oven were such that the temperature was raised to 325 ° C. at 10 ° C./min after holding at 50 ° C. for 2 minutes, the temperature of the vaporization chamber was set to 225 ° C., and the temperature of the FID detector was set to 350 ° C. The injection volume of the sample solution was 0.5 ul.

(Production Example: Production of Polymer A1)
Polyoxypropylene triol (molecular weight: 330 per functional group) obtained by ring-opening addition polymerization of propylene oxide to glycerin was used as an initiator (hereinafter referred to as "initiator A").
Propylene oxide (1,522 g) was added to initiator A (64.1 g) in the presence of t-butyl alcohol complex catalyst (0.08 g) of zinc hexacyanocobaltate, and the pressure of the reaction system did not fall at 120 ° C. It was made to react. Thus, a precursor polymer a1 having a polyoxypropylene chain and having three hydroxyl groups per molecule at the end of the main chain was obtained. The viscosity of the precursor polymer a1 at 25 ° C. was 24 Pa · s, the Mn was 30,000, and the Mw / Mn was 1.17.
The precursor polymer a1 was alcoholated by adding a methanol solution containing 1.05 moles of sodium methoxide to the amount of hydroxyl groups of the precursor polymer a1 to the precursor polymer a1. Next, after distilling off methanol by heating and pressure reduction, an excess amount of allyl chloride was added to the amount of hydroxyl groups of the precursor polymer a1. Thus, a polymer having a polyoxypropylene chain and having an allyl group at all of the main chain terminals was obtained.
Next, in the presence of chloroplatinic acid hexahydrate, 0.72 times equivalent amount of dimethoxymethylsilane with respect to the equivalent of the allyl group at the main chain end of the polymer having an allyl group at the entire main chain end obtained. The reaction solution was added and reacted at 70 ° C. for 5 hours to obtain a polymer A1 having a polyoxypropylene chain and a dimethoxymethylsilyl group at the main chain terminal.

(Process 1 of organic silicon compound)
10 kg of crude PTMS (Hexamethyldisilazane content: 0.2% by mass, described as "unrefined PTMS" in Table 1) is charged into a 20 L reactor, and the temperature is raised from normal temperature to 60 ° C. At the same time as the start, depressurization was started so as to be 10 mmHg from normal pressure. After the internal pressure of the reactor reached 10 mmHg, the content of hexamethyldisilazane in the system was determined by the above method after degassing under reduced pressure for 2 hours and after degassing under reduced pressure for 4 hours. 100 ppm of hexamethyldisilazane was contained in PTMS after vacuum degassing for 2 hours. (Hereafter, it is called "PTMS-A."). The amount of hexamethyldisilazane in PTMS after vacuum degassing for 4 hours was below the detection limit (hereinafter referred to as "PTMS-B").
(Process 2 of organic silicon compound)
Crude PTMS is crude TMP-3TMS (hexamethyldisilazane content: 0.2% by mass, referred to as "unrefined TMPS" in Table 2), and the temperature is 120 ° C. It operated. 100 ppm of hexamethyldisilazane was contained in TMP-3TMS after vacuum degassing for 2 hours (hereinafter referred to as "TMPS-A"). The amount of hexamethyldisilazane in TMP-3TMS after vacuum degassing for 4 hours was below the detection limit (hereinafter referred to as "TMPS-B").

(Example 1)
A curable composition was obtained by mixing 5 parts by weight of tung oil, 1 part by weight of an organic silicon compound, and 200 ppm of water with 100 parts by weight of the polymer A1 obtained in Synthesis Example 1. The results of the storage stability test conducted on the obtained curable composition are shown in Table 1.
(Example 2-3)
A curable composition was obtained in the same manner as in Example 1 except that the composition shown in Table 1 was used. Table 1 shows the results of the storage stability test.
(Examples 4 to 6)
A curable composition was obtained in the same manner as in Example 1 except that the formulations shown in Table 2 were used. Table 2 shows the results of the storage stability test.

  In Example 3 which used PTMS which did not process, thickening was seen by preservation | save compared with Example 1 or Example 2. In Example 6 which used TMP-3TMS which did not process, thickening was seen by preservation | save as Example 4 and Example 5.

  The curable composition of the present invention is excellent in storage stability under conditions of higher temperature than the conventional ones, so it is resistant to deterioration even in long-term transportation through the vicinity of the equator, such as shipping. The curable composition of the present invention comprises an adhesive, a sealant (elastic sealant for construction, a sealant for double glazing, etc.), a sealant (a rustproof / waterproof sealant for a glass end, a solar cell). Back surface sealants etc.), Sealants (Building sealants, Marine sealants, Automotive sealants, Road sealants etc.), Electrical insulating materials (Insulation coatings for electric wires and cables), etc. It is suitably used in the field.

Claims (10)

A curable composition comprising a polymer having a reactive silicon group represented by the following formula 1, an organosilicon compound represented by the following formula 2, and an organosilazane represented by the following formula 3:
The curable composition whose content rate of the said organosilazane is less than 0.2 mass% with respect to the said organosilicon compound.
-SiX _a (R ¹ ) _(3-a) ... Formula 1
[In Formula 1, R ¹ is a monovalent organic group having 1 to 20 carbon atoms and represents an organic group other than a hydrolysable group, X represents a hydroxyl group or a hydrolysable group, and a is 1 to 3] And when a is 1, R ¹ may be the same as or different from each other. When a is 2 or more, X may be the same or different. ]
(R ² (CH ₃ ) ₂ SiO) _n R ³ ... Formula 2
[In Formula 2, R ² represents a saturated or unsaturated monovalent hydrocarbon group having 1 to 4 carbon atoms, and R ³ represents a residue obtained by removing some or all of the hydroxyl groups from the hydroxyl group-containing compound , N represents a positive integer. ].
(R ⁴ ) ₃ SiNHSi (R ⁴ ) ₃ ... Formula 3
[In Formula 3, R ⁴ represents a saturated or unsaturated monovalent hydrocarbon group having 1 to 4 carbon atoms, and may be the same as or different from each other. ].   The main chain skeleton of the polymer having a reactive silicon group is a polymer having a unit based on an alkylene oxide monomer, a polymer having one or both units based on an alkyl acrylate ester or an alkyl methacrylate ester. The curable composition according to claim 1, which is one selected from the group consisting of and saturated hydrocarbon polymers.   The curable composition according to claim 1, wherein the polymer having a reactive silicon group includes a polymer having a main chain skeleton having a unit based on an alkylene oxide monomer.   The curable composition according to claim 2, wherein a molecular weight distribution of the polymer having a unit based on the alkylene oxide monomer is 1.0 to 1.6.   The curable composition according to any one of claims 1 to 4, wherein the organic silicon compound is either or both of phenyltrimethylsilyl ether and trimethylolpropane tris (trimethylsilyl) ether.   The curable composition according to any one of claims 1 to 5, wherein the organic silicon compound has a reduced content of the organosilazane contained in the organic silicon compound.   The curable composition according to any one of claims 1 to 6, wherein the organosilazane is hexamethyldisilazane.   The curable composition according to any one of claims 1 to 7, which is for an adhesive.   The curable composition according to any one of claims 1 to 7, which is for a sealant material.   Hardened | cured material formed by hardening | curing the curable composition as described in any one of Claims 1-7.