JP6652213B2 - Curable composition and cured product - Google Patents

Description

  The present invention relates to a curable composition containing a polymer having a reactive silicon group, and a cured product thereof.

  The liquid curable composition containing the oxyalkylene polymer having a reactive silicon group is cured by a hydrolysis reaction with a catalyst or the like, and forms a flexible rubber-like cured product. Such cured products are widely used as sealants, adhesives, coatings and the like.

  Patent Document 1 describes a curable composition having good curability, elongation after curing, durability, and good suppression of surface stickiness. This curable composition has a polymer (A) having an oxyalkylene polymer as a main chain and having two to three terminals, and each terminal having 1.0 or less reactive silicon groups introduced thereinto, And at least two kinds of compounds (B) that generate trimethylsilanol. The favorable properties described above can be adjusted by the combination and compounding ratio of the compound (B). Further, it is shown that when the compound (B) is contained in an amount of more than 2 parts by mass with respect to 100 parts by mass of the polymer (A), the curability is remarkably deteriorated (Test No. 31).

  Patent Literature 2 describes an invention which aims to provide a curable composition having excellent curability, flexibility after curing, and recovery rate. As an example of the curable composition, a polymer (A) having an average of more than 1.0 reactive silicon groups at each of two terminals of a polymer having a main chain such as an oxyalkylene polymer And a compound containing a compound (B) which generates silanol by hydrolysis. Specifically, a curable composition containing 0.75 parts by mass of the compound (B) with respect to 100 parts by mass of the polymer (A) or the comparative polymer is described (Examples 1, 3 and Comparative Examples). Examples 2, 4, 5). The compounding amount of the compound (B) used in Patent Document 2 is within the range of the compounding amount considered good in Patent Document 1, and in order to avoid the deterioration of the curability as shown in Patent Document 1. The compounding amount of the compound (B) is kept low.

JP 2015-10162 A JP 2015-105323 A

In recent years, with the improvement of the service life of a detached house, the sealing material is required to have a longer-term durability (ie, fatigue resistance) than before. At this time, from the viewpoint of shortening the construction period, the curability of the cured product is equal to or higher than the conventional one, and the surface of the cured material is less sticky in order to keep the surface of the cured sealing material clean, Desired.
The present invention provides a curable composition that is excellent in curability, has less stickiness on the surface of a cured product, and is excellent in fatigue resistance.

[1] An oxyalkylene polymer having an average of more than 1.0 reactive silicon groups represented by the following formula 1 at one main chain terminal and a silanol represented by the following formula Z by hydrolysis: A curable composition comprising: a silicon compound to be produced; and 1.0 to less than 4.0 parts by mass of the silicon compound with respect to 100 parts by mass of the oxyalkylene polymer.
—SiX _a R _3-a (Formula 1)
L ₃ SiOH (Formula Z)
[In the formula 1, R is a monovalent organic group having 1 to 20 carbon atoms and represents an organic group other than a hydrolyzable group, and X represents a hydroxyl group or a hydrolyzable group. a is an integer of 1 to 3. When a is 1, R may be the same or different. When a is 2 or more, Xs may be the same or different. In Formula Z, L independently represents a substituted or unsubstituted monovalent hydrocarbon group or a hydrogen atom. ]
[2] The curable composition according to [1], wherein at least one main chain terminal of the oxyalkylene polymer is an atomic group represented by the following formula 2.

[Wherein, R ¹ and R ³ each independently represent a divalent bonding group having 1 to 6 carbon atoms, and the atoms bonded to the carbon atoms in the bonding group are a carbon atom, a hydrogen atom, an oxygen atom, It is a nitrogen atom or a sulfur atom. R ² and R ⁴ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. n shows the integer of 1-10. R ⁵ is each independently a monovalent organic group having 1 to 20 carbon atoms, and represents an organic group other than a hydrolyzable group, and Y each independently represents a hydroxyl group or a hydrolyzable group. b is an integer of 1 to 3. When a plurality of R ⁵ are present, R ⁵ may be the same or different from each other. When a plurality of Ys are present, the Ys may be the same or different. ]
[3] The terminal group at the main chain terminal of the oxyalkylene polymer is any of a reactive silicon group, an active hydrogen-containing group, or an unsaturated group represented by the formula 1, [1] or [2]. ] The curable composition as described in [1].
[4] The oxyalkylene polymer has two main chain terminals in one molecule, and each main chain terminal has any one of a reactive silicon group, an active hydrogen-containing group and an unsaturated group represented by the above formula 1. The curable composition according to any one of [1] to [3], which has two terminal groups.
[5] The terminal group at the terminal of the main chain is any of a reactive silicon group, an active hydrogen-containing group, or an unsaturated group represented by the above formula 1, and on the average of one main chain terminal in the above formula 1, The curable composition according to any one of [1] to [4], further including an oxyalkylene polymer having more than 0.5 and not more than 1.0 reactive silicon groups represented.
[6] The terminal group at one terminal of the main chain is an inactive monovalent organic group, and the number of reactive silicon groups represented by the above formula 1 is zero on average at each main chain terminal in one molecule. The curable composition according to any one of [1] to [5], further comprising an oxyalkylene polymer having more than 0.5 oxyalkylene polymer.
[7] The silicon compound according to [1] to [6], wherein the silicon compound is at least one selected from the group consisting of phenoxytrimethylsilane, trimethylolpropane tris (trimethylsilyl) ether, tetramethyldisilazane, and hexamethyldisilazane. The curable composition according to claim 1.
[8] The curable composition according to any one of [1] to [7], which is used for a sealing material.
[9] A cured product of the curable composition according to any one of [1] to [8].

The curable composition of the present invention is excellent in curability, has little stickiness on the surface of the cured product, and is excellent in fatigue resistance.
According to the composition for a sealing material of the present invention, it is excellent in curability, so that it is possible to prevent the application period from being prolonged, and since the surface of the cured sealing material has a low stickiness, it is difficult for dust to be attached, and is excellent in fatigue resistance. Therefore, the service life of a building such as a house can be extended.

The definitions of the terms in this specification are as follows.
The numerical range represented by “to” means a numerical range in which the numerical values before and after the lower limit are the lower limit and the upper limit.
The “unit” constituting the polymer means an atomic group directly formed by polymerization of a monomer.
"Oxyalkylene polymer" means a polymer having a polymer chain formed from units based on alkylene oxide monomers.
“Main chain terminal” means an atomic group bonded to a terminal atom constituting the main chain.
The “(meth) acrylate polymer” means a polymer having a polymer chain formed from a unit based on an alkyl (meth) acrylate.
“(Meth) acrylic acid” means one or both of acrylic acid and methacrylic acid.

An “unsaturated group” as a terminal group is a monovalent group containing a carbon-carbon unsaturated bond.
The “active hydrogen-containing group” is at least one group selected from the group consisting of a hydroxyl group, a carboxy group, an amino group, a secondary amino group, a hydrazide group and a sulfanyl group.
“Active hydrogen” is a hydrogen atom based on the above active hydrogen-containing group.
"Silylation rate" is the number of the reactive silicon groups based on the total number of terminal groups, which are either reactive silicon groups, active hydrogen-containing groups or unsaturated groups, introduced into the main chain terminal of the polymer. Is the ratio of The value of the silylation rate can be measured by NMR analysis. Further, the ratio of the number of silyl groups of the added silylating agent to the number of terminal groups at the ends of the main chain when the reactive silicon group is introduced into the main chain terminals of the polymer by the silylating agent described below ( Mol%).
“Silylating agent” means a compound having a functional group that reacts with an active hydrogen-containing group or an unsaturated group and a reactive silicon group.
The number average molecular weight (hereinafter referred to as “Mn”) and the weight average molecular weight (hereinafter referred to as “Mw”) are molecular weights in terms of polystyrene obtained by gel permeation chromatography (GPC) measurement. The molecular weight distribution is a value calculated from Mw and Mn, and is a ratio of Mw to Mn.

  The curable composition of the present invention is an oxyalkylene polymer having an average of more than 1.0 reactive silicon groups represented by the following formula 1 at one main chain terminal (hereinafter referred to as “polymer A”). ) And a silicon compound that produces a silanol represented by the following formula Z when hydrolyzed (hereinafter, referred to as “silicon compound Z”).

<Reactive silicon group>
The reactive silicon group is represented by the following formula 1. The reactive silicon group has a hydroxyl group or a hydrolyzable group bonded to the silicon atom, and can form a siloxane bond to crosslink. The reaction to form siloxane bonds is promoted by the curing catalyst.
—SiX _a R _3-a Formula 1

In Formula 1, R represents a monovalent organic group having 1 to 20 carbon atoms. R does not contain a hydrolyzable group.
R is preferably at least one selected from the group consisting of a hydrocarbon group having 1 to 20 carbon atoms and a triorganosiloxy group.

  R 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 a linear or branched alkyl group having 1 to 4 carbon atoms, a cyclohexyl group, a phenyl group, a benzyl group, an α-chloromethyl group, a trimethylsiloxy group, a triethylsiloxy group and a triphenylsiloxy group Is more preferable. A methyl group or an ethyl group is preferable because the curability and stability of the polymer having a reactive silicon group are well balanced. An α-chloromethyl group is preferred because the curing rate of the cured product is high. A methyl group is particularly preferred because it is easily available.

In Formula 1, X represents a hydroxyl group or a hydrolyzable group.
Examples of the hydrolyzable group include a hydrogen atom, a halogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, a sulfanyl group, and an alkenyloxy group.
Alkoxy groups are preferred from the viewpoint of gentle hydrolysis and easy handling. The alkoxy group is preferably a methoxy group, an ethoxy group, or an isopropoxy group, and more preferably a methoxy group or an ethoxy group. When the alkoxy group is a methoxy group or an ethoxy group, a siloxane bond is quickly formed, a crosslinked structure is easily formed in the cured product, and the physical properties of the cured product are easily improved.

In Formula 1, a represents an integer of 1 to 3. When a is 1, R may be the same or different from each other. When a is 2 or more, Xs may be the same or different from each other.
A is preferably 1 or 2, and a is more preferably 2, in order to further enhance the effects of the curable composition of the present invention such as curability, fatigue resistance after curing, and suppression of surface stickiness.

  The reactive silicon group represented by the formula 1 includes a trimethoxysilyl group, a triethoxysilyl group, a triisopropoxysilyl group, a tris (2-propenyloxy) silyl group, a triacetoxysilyl group, a dimethoxymethylsilyl group, Examples include an ethoxymethylsilyl group, a dimethoxyethylsilyl group, a diisopropoxymethylsilyl group, a (α-chloromethyl) dimethoxysilyl group, and an (α-chloromethyl) diethoxysilyl group. Trimethoxysilyl, triethoxysilyl, dimethoxymethylsilyl and diethoxymethylsilyl groups are preferred, and dimethoxymethylsilyl and trimethoxysilyl groups are more preferred, in that high activity and good curability are obtained.

  The main chain structure of the polymer A is preferably linear, and may have a branched chain. In the main chain of the polymer A, a site where 20 or more units constituting the polymer A are linked is regarded as the main chain. Therefore, both chains extending from the branch point of the branched chain may be regarded as the main chain. Branch points are not considered ends of the main chain.

The main chain of the polymer A is a polymer chain composed of an oxyalkylene polymer formed by polymerization of one or more alkylene oxide monomers. When it is a copolymer chain formed by polymerization of two or more alkylene oxide monomers, those alkylene oxide monomers may form a block polymer or a random polymer. Good.
As a polymer chain consisting of an oxyalkylene polymer, a polymer chain consisting of an ethylene oxide monomer, a polymer chain consisting of a propylene oxide monomer, a polymer chain consisting of a butylene oxide monomer, a polymer chain consisting of a tetramethylene oxide monomer, Examples thereof include a copolymer chain of an ethylene oxide monomer and a propylene oxide monomer, and a copolymer chain of a propylene oxide monomer and a butylene oxide monomer. Particularly, a polymer chain composed of a propylene oxide monomer is preferable.

  It is preferable that at least one main chain terminal of the polymer A is an atomic group represented by the following formula 2.

In Formula 2, R ¹ and R ³ each independently represent a divalent bonding group having 1 to 6 carbon atoms, and the atoms bonded to the carbon atoms in the bonding group are a carbon atom, a hydrogen atom, an oxygen atom, It is a nitrogen atom or a sulfur atom.
_-CH 2 as R ^{1, R 3} is _{-, - C 2 H 4 -} , - C 3 H 6 -, - C 4 H 8 -, - C 5 H 10 -, - C 6 H 12 -, - C ( _{CH 3) 2 -, - CH} 2 -O-CH 2 -, - CH 2 -O-CH 2 -O-CH 2, -C = C -, - C≡C -, - CO -, - CO-O -, -CO-NH-, -CH = N-, -CH = NN-CH =.
R ¹ is _{-CH 2 OCH 2 -, - CH} 2 O -, - CH 2 - are _preferred, -CH ₂ OCH 2 - is more preferable.
R ³ is preferably —CH ₂ — or —C ₂ H ₄ —, and more preferably —CH ₂ —.

In Formula 2, R ² and R ⁴ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. As the hydrocarbon group, a linear or branched alkyl group having 1 to 10 carbon atoms is preferable.
Examples of the linear alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.
Examples of the branched alkyl group include isopropyl, s-butyl, t-butyl, 2-methylbutyl, 2-ethylbutyl, 2-propylbutyl, 3-methylbutyl, 3-ethylbutyl, and 3-propyl. Butyl, 2-methylpentyl, 2-ethylpentyl, 2-propylpentyl, 3-methylpentyl, 3-ethylpentyl, 3-propylpentyl, 4-methylpentyl, 4-ethylpentyl , 4-propylpentyl, 2-methylhexyl, 2-ethylhexyl, 2-propylhexyl, 3-methylhexyl, 3-ethylhexyl, 3-propylhexyl, 4-methylhexyl, 4-ethylhexyl Group, 4-propylhexyl group, 5-methylhexyl group, 5-ethylhexyl group, 5-propylhexyl Group can be exemplified.
R ² and R ⁴ are each preferably a hydrogen atom, a methyl group, or an ethyl group, and more preferably a hydrogen atom or a methyl group.

  In Formula 2, n represents an integer of 1 to 10. n is preferably 1 to 7, more preferably 1 to 5, and still more preferably 1.

In Formula 2, R ⁵ is each independently a monovalent organic group having 1 to 20 carbon atoms, and represents an organic group other than a hydrolyzable group, and Y each independently represents a hydroxyl group or a hydrolyzable group. . b is an integer of 1 to 3. When a plurality of R ⁵ are present, R ⁵ may be the same or different from each other. When a plurality of Ys are present, the Ys may be the same or different.
R ^{5 in} Formula 2 is the same as R in Formula 1.
Y in Equation 2 is the same as X in Equation 1.
B in Equation 2 is the same as a in Equation 1.

Mn of the polymer A is preferably from 3,000 to 100,000, more preferably from 4,000 to 50,000, and still more preferably from 5,000 to 30,000. When Mn is at least the lower limit of the above range, the amount of the reactive silicon group introduced per mass of the polymer A is not too large, which is preferable in view of production cost. When it is less than the upper limit, the viscosity becomes sufficiently low and the workability is easily improved.
The molecular weight distribution of the polymer A is preferably 1.80 or less, more preferably 1.50 or less, further preferably 1.40 or less, and particularly preferably 1.20 or less. When the molecular weight distribution is less than the above upper limit, the fatigue resistance of the cured product tends to be improved.

The total number of divalent or higher valent atoms contained in one main chain terminal of the polymer A is preferably 80 or less, more preferably 50 or less, and even more preferably 40 or less.
The total number of divalent or higher valent atoms contained in one main chain terminal is preferably 1 or more, more preferably 4 or more, further preferably 10 or more, and particularly preferably 20 or more.
As the divalent or higher valent atom, one or more atoms selected from a carbon atom, a nitrogen atom, an oxygen atom, a sulfur atom and a silicon atom are preferable, and one or more atoms selected from a carbon atom, a nitrogen atom, an oxygen atom and a silicon atom are preferable. The above atoms are more preferable, and one or more atoms selected from a carbon atom, an oxygen atom and a silicon atom are more preferable.
The polymer A preferably has 2 to 8 main chain terminals in one molecule, more preferably has 2 to 6 main chain terminals, more preferably has 2 or 3 main chains, and particularly preferably has 2 main chain terminals. .
The polymer A has two main chain terminals in one molecule, and each main chain terminal has a terminal group which is any of a reactive silicon group, an active hydrogen-containing group or an unsaturated group represented by the above formula 1. It is more preferable that the compound has four or more terminal groups in one molecule and has a silylation rate of more than 50 mol% and 100 mol% or less.
In the case where two terminal groups are provided at one main chain terminal and four terminal groups are present in one molecule, if the molecular weight and the silylation rate are the same, the terminal group is connected to one main chain. It has one at the chain end, and tends to have larger elongation properties than a polymer having four terminal groups in one molecule.
The polymer A is obtained by introducing more than one reactive silicon group on the average into one main chain terminal of the precursor polymer.
The method for producing the polymer A is such that, after an average of more than 1.0 unsaturated groups are introduced into one main chain terminal of the precursor polymer, the unsaturated group is reacted with the silylating agent. The method is preferred.
The precursor polymer of the polymer A is an oxyalkylene polymer obtained by ring-opening addition polymerization of an alkylene oxide monomer to active hydrogen of an initiator having an active hydrogen-containing group in the presence of a ring-opening polymerization catalyst. The number of active hydrogens of the initiator, the number of main chain terminals of the precursor polymer, and the number of main chain terminals of the polymer A are the same. Mn of the precursor polymer is substantially equal to Mn of the polymer A.
The precursor polymer is preferably a polymer obtained by subjecting an alkylene oxide monomer to ring-opening addition polymerization with an initiator having a hydroxyl group, wherein the terminal group at the terminal of the main chain is a hydroxyl group.
As the initiator, an initiator having 2 to 8 hydroxyl groups is preferable, an initiator having 2 to 6 hydroxyl groups is more preferable, and an initiator having 2 hydroxyl groups or an initiator having 3 hydroxyl groups is further preferable. One type of initiator may be used alone, or two or more types may be used in combination.
Examples of the initiator having two hydroxyl groups include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, and a low molecular weight. Of polyoxypropylene glycol can be exemplified.
Examples of the initiator having three hydroxyl groups include glycerin, trimethylolpropane, trimethylolethane, and low molecular weight polyoxypropylene triol.
Examples of the initiator having four or more hydroxyl groups include pentaerythritol and sorbitol.
The main chain of the polymer A is preferably straight-chain from the viewpoint of excellent elongation properties of the cured product. Therefore, as the initiator, a compound having two active hydrogen-containing groups is preferable, and a compound having two hydroxyl groups is more preferable.

When obtaining the precursor polymer, as a catalyst for ring-opening addition polymerization of an alkylene oxide monomer as an initiator, a double metal cyanide complex, an alkali metal such as potassium hydroxide, and a transition metal compound such as an organoaluminum compound Metal porphyrin, phosphazene, etc., such as a complex obtained by reacting porphyrin with porphyrin. The complex metal cyanide complex is preferable because the molecular weight distribution of the obtained polymer can be narrowed and a curable composition having a low viscosity is easily obtained.
As the double metal cyanide complex, a conventionally known compound can be used, and a known method can be adopted as a method for producing a polymer using the double metal cyanide complex. For example, WO2003 / 063011, WO2004 / 067633, JP-A-2004-269776, JP-A-2005-15786, WO2013 / 065802, JP-A-2015-010162 The compounds and production methods disclosed in the above can be used.
The double metal cyanide complex is preferably a double metal cyanide complex in which glyme or t-butyl alcohol is coordinated as an organic ligand to the catalyst skeleton. The catalyst skeleton is more preferably Zn ₃ [Co (CN) ₆ ] ₂ (that is, a zinc hexacyanocobaltate complex). The double metal cyanide complex using t-butyl alcohol as the organic ligand can easily control the molecular weight distribution of the obtained precursor polymer to 1.20 or less.

  As a method of introducing an average of more than 1.0 unsaturated groups into one main chain terminal of the precursor polymer, an alkali metal salt is allowed to act on the precursor polymer, and then an epoxy group having an unsaturated group is introduced. A method of reacting a compound and then reacting a halogenated hydrocarbon compound having an unsaturated group is preferred.

  As the epoxy compound having an unsaturated group, a compound represented by the following formula 3 is preferable.

^R 1, ^{R 2} of formula 3 is the same as ^R 1, ^{R 2} of Formula 2.
Examples of the epoxy compound having an unsaturated group include allyl glycidyl ether, methallyl glycidyl ether, glycidyl acrylate, glycidyl methacrylate, butadiene monoxide, and 1,4-cyclopentadiene monoepoxide. Allyl glycidyl ether is preferred.
As a method for introducing more than 1.0 unsaturated groups into one main chain terminal of the precursor polymer, known methods can be used without any particular limitation. For example, WO 2013/180203, WO 2014/192842, JP-A-2015-105293, JP-A-2005-105322, JP-A-2015-105323, JP-A-2015-105324, WO 2015/080067, WO 2015/2015 / 105122, WO 2015/111577, WO 2016/002907, JP-A-2006-216633, and JP-A-2017-39792.

By the above reaction, an unsaturated group derived from the epoxy compound having an unsaturated group is introduced into the main chain terminal of the precursor polymer, and then an intermediate having an unsaturated group derived from the halogenated hydrocarbon compound is introduced. can get. The intermediate may be an unreacted active hydrogen-containing group at a part of the terminal group at the main chain terminal.
The number of active hydrogen-containing groups contained in one molecule of the intermediate is preferably 0.3 or less, more preferably 0.1 or less from the viewpoint of storage stability.

The polymer A is obtained by reacting the unsaturated group of the intermediate with a silylating agent to introduce a reactive silicon group at the terminal of the main chain.
As the silylating agent, a compound having both a group capable of forming a bond by reacting with an unsaturated group (for example, a sulfanyl group) and the above reactive silicon group, a hydrosilane compound (for example, HSiX _a R _3-a ; , R, and a are the same as those in the above formula 1.). Specifically, for example, trimethoxysilane, triethoxysilane, triisopropoxysilane, tris (2-propenyloxy) silane, triacetoxysilane, dimethoxymethylsilane, diethoxymethylsilane, dimethoxyethylsilane, diisopropoxymethyl Examples thereof include silane, (α-chloromethyl) dimethoxysilane, and (α-chloromethyl) diethoxysilane. Trimethoxysilane, triethoxysilane, dimethoxymethylsilane, and diethoxymethylsilane are preferred, and dimethoxymethylsilane or trimethoxysilane is more preferred, in that high activity and good curability are obtained.

  By the above reaction, the terminal group at the terminal of the main chain is any of the above reactive silicon group, active hydrogen-containing group or unsaturated group, and more than 1.0 of the above reactive groups are averaged at one main chain terminal. A polymer A having a silicon group is obtained.

  The terminal group at the main chain terminal of the polymer A is any of a reactive silicon group, an active hydrogen-containing group, or an unsaturated group represented by the above formula 1, because the elongation property of the cured product is easily improved. Is preferred. The polymer A is a cured product in which the mechanical properties are good and the elongation properties are easily obtained, and the terminal group at the main chain terminal is a reactive silicon group represented by the above formula 1, an active hydrogen-containing group, or an unsaturated group. Group, and preferably has two terminal groups at one main chain terminal, and more preferably has three or more terminal groups in one molecule.

The silylation rate of the polymer A is preferably more than 50 mol% and 100 mol% or less, more preferably 60 to 97 mol%, and further preferably 65 to 95 mol%.
In the case of having two terminal groups at one main chain terminal, if the silylation ratio is more than 50%, more than 1.0 reactive silicon groups are present on average at one main chain terminal.
The silylation rate can be adjusted by the amount of the reactive silicon group-containing compound reacted with the unsaturated group of the intermediate.
When the curable composition described below contains two or more types of polymer A, the average silylation rate in the entire polymer A may be within the above range. The average silylation rate can be calculated as a weighted average of the silylation rates of the respective polymers A.

  Since the reactive silicon group of the polymer A contained in the curable composition of the present invention has a hydroxyl group or a hydrolyzable group bonded to a silicon atom, it can form a siloxane bond. The reaction for forming a siloxane bond is promoted by a curing catalyst described later.

  The polymer A contained in the curable composition of the present invention may be one type or two or more types. For example, it may be one kind of polymer having one kind of main chain structure, or a mixture of two or more kinds of polymers having different main chain structures.

  The curable composition of the present invention may contain an oxyalkylene polymer other than the polymer A. Specifically, for example, it may include one or both of a polymer B and a polymer C described below.

<Silicon compound Z>
The silicon compound Z is a compound that generates a silanol represented by the following formula Z by hydrolysis, and contains a group represented by the following formula Z1. The water required for the hydrolysis can be supplied from the air in the environment where the curable composition of the present invention is applied. The generated silanol can react with the polymer A and a polymer B described later. Since the curable composition of the present invention contains a specific amount of the silicon compound Z, the curable composition is excellent in curability, the surface of the cured product after curing is less sticky, and the cured product has improved fatigue resistance.
L ₃ SiOH (Formula Z)
L ₃ Si- ··· (formula Z1)
[In the formulas Z and Z1, L independently represents a substituted or unsubstituted monovalent hydrocarbon group or a hydrogen atom. ]

L in the formulas Z and Z1 is preferably independently a hydrogen atom, a linear or branched alkyl group having 1 to 20 carbon atoms, or an aromatic group having 6 to 20 carbon atoms. As the linear or branched alkyl group having 1 to 20 carbon atoms, a linear or branched alkyl group having 1 to 4 carbon atoms is preferable, and a linear alkyl group having 1 to 4 carbon atoms is more preferable. preferable. L is preferably a hydrogen atom, a methyl group or an ethyl group, and more preferably a methyl group.
The molecular weight of the silicon compound Z is preferably 2,000 or less, more preferably 500 or less, from the viewpoint of increasing the dispersibility in the curable composition, suppressing the surface stickiness of the cured product, and the like.
The number of groups represented by the above formula Z1 in the silicon compound Z is preferably 0.5 to 8.0 on average in one molecule, and more preferably 0.9 to 4.0 on average.

As the silicon compound Z, a compound obtained by trialkylsilyloxylation of a hydroxyl group of a hydroxy compound or a compound represented by the formula Z1-1 is preferable.
L ₃ Si—NH—U (Formula Z1-1)
[Wherein, L is the same as in Formula Z or Z1, and U represents a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms, or SiL ₃ (L is the same as described above). . ]
As L in formula Z1-1, each independently preferably represents a hydrogen atom or a linear alkyl group having 1 to 4 carbon atoms, and more preferably a hydrogen atom, a methyl group or an ethyl group.
The U in formula Z1-1, number 1-6 haloalkyl group carbon, preferably a carbonyl group or SiL ₃ of 1 to 6 carbon atoms, a chloroalkyl group having 1 to 6 carbon atoms, fluoroalkyl of 1 to 6 carbon atoms A carbonylalkyl group having 1 to 4 carbon atoms or SiL ₃ in which L is each independently a hydrogen atom, a methyl group or an ethyl group, is more preferable, and a monochloromethyl group, a monofluoromethyl group, a dichloromethyl group, a difluoromethyl group, or L is each independently a hydrogen atom, more preferably SiL ₃ is a methyl group or an ethyl group, L is each independently a hydrogen atom, is SiL ₃ is a methyl group or an ethyl group is particularly preferred.
Examples of the compound obtained by subjecting the hydroxyl group of the hydroxy compound to trialkylsilyloxylation include, for example, CH ₃ OSi (CH ₃ ) ₃ , CH ₃ CH ₂ OSi (CH ₃ ) ₃ , and CH ₃ CH (CH ₃ ) OSi (CH ₃ ) ) ₃ , CH ₃ CHClCH ₂ OSi (CH ₃ ) ₃ , ClCH ₂ CH ₂ OSi (CH ₃ ) ₃ , C ₆ H ₅ OSi (CH ₃ ) ₃ (phenoxytrimethylsilane), m-CH ₃ C ₆ H ₄ OSi _{(CH 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 C _{2 OSi (CH 3) 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 Phenoxytrimethylsilane or TMP-3TMS is preferred because of its good reactivity with the union A and the polymer B described below.

  Examples of the compound represented by the above formula Z1-1 include tetramethyldisilazane, N-trimethylsilylacetamide, bis (chloromethyl) tetramethyldisilazane, and hexamethyldisilazane. Tetramethyldisilazane or hexamethyldisilazane is preferred because of its good reactivity with B.

The curable composition of the present invention may contain only one kind of the silicon compound Z, or may contain two or more kinds thereof.
As the silicon compound Z, it is preferable to use one or more selected from the group consisting of phenoxytrimethylsilane, TMP-3TMS, tetramethyldisilazane and hexamethyldisilazane, and either one of phenoxytrimethylsilane and TMP-3TMS or It is preferable to include both.
When two or more silicon compounds Z are used in combination, the hydrolysis rates of the silicon compounds Z are preferably different from each other.
The hydrolysis rate of the silicon compound Z may be faster, the same as, or slower than the hydrolysis rate of the reactive silicon group of the polymer A.

Examples of the combination of the silicon compounds Z having different hydrolysis rates include a combination of phenoxytrimethylsilane and TMP-3TMS.
TMP-3TMS has a lower hydrolysis rate than phenoxytrimethylsilane and a lower hydrolysis rate than the hydrolysis rate of the reactive silicon group represented by the above formula 1. Therefore, when TMP-3TMS is used as the silicon compound Z, the curing reaction of the polymer A easily proceeds quickly, and contributes to excellent curability.
Phenoxytrimethylsilane has a higher hydrolysis rate than TMP-3TMS, and has a higher hydrolysis rate than the hydrolysis rate of the reactive silicon group represented by the above formula (1). Therefore, when phenoxytrimethylsilane is used as the silicon compound Z, the curing reaction of the polymer A is slowed down, but contributes to the excellent fatigue resistance of the cured product.
When both TMP-3TMS and phenoxytrimethylsilane are included, the mass ratio (TMP-3TMS / phenoxytrimethylsilane) of the amounts of both is preferably 10/90 to 90/10, and 20/80 to 80/20. More preferred.
When the mass ratio is within the above range, the effects of curability and fatigue resistance can be obtained in a well-balanced manner.
The total ratio of TMP-3TMS and phenoxytrimethylsilane to the total mass of the silicon compound Z contained in the curable composition of the present invention is preferably 60% by mass or more, more preferably 80% by mass or more, and 100% by mass. % Is more preferred.
When the above ratio is equal to or more than the above lower limit, the effects of curability and fatigue resistance can be obtained in a well-balanced manner.

<Polymer B>
In the curable composition of the present invention, the terminal group at the terminal of the main chain is any of a reactive silicon group, an active hydrogen-containing group, or an unsaturated group represented by the above formula 1, and the terminal group has an average And an oxyalkylene polymer having more than 0.5 and not more than 1.0 reactive silicon groups represented by the above formula 1 (hereinafter, referred to as “polymer B”).
Examples of the main chain of the polymer B are the same as those of the main chain of the polymer A.
The number of the terminal groups in one molecule of the polymer B is preferably 2 to 6, and more preferably 2 to 3. Two or more terminal groups present in one molecule of the polymer B may be the same or different.
The polymer B contained in the curable composition of the present invention may be one type or two or more types.

Mn of the polymer B is preferably from 4,000 to 50,000, more preferably from 5,000 to 40,000, even more preferably from 6,000 to 30,000. When Mn is equal to or more than the lower limit of the above range, the curability of the curable composition of the present invention is excellent, the stickiness of the surface of the cured product is easily suppressed, and the fatigue resistance is easily excellent.
The molecular weight distribution of the polymer B is preferably 1.8 or less. From the viewpoint of viscosity reduction, the molecular weight distribution is preferably smaller, more preferably 1.5 or less, still more preferably 1.4 or less, and particularly preferably 1.2 or less.

The polymer B preferably has an average of 0.6 to 0.97 reactive silicon groups represented by the above formula 1 at one main chain terminal, and preferably 0.7 to 0.95. Is more preferable.
The total number of divalent or higher valent atoms contained in one main chain terminal of the polymer B is preferably 80 or less, more preferably 50 or less, and even more preferably 40 or less.
The total number of divalent or higher valent atoms contained in the one main chain terminal is preferably one or more, more preferably two or more, still more preferably four or more, and particularly preferably eight or more.
The kind of the divalent or higher valent atom is the same as that of the polymer A, and the preferable range is also the same.
The polymer B having a reactive silicon group is obtained by introducing a reactive silicon group into the main chain terminal of the precursor polymer.
The precursor polymer of the polymer B can be produced in the same manner as the precursor polymer of the polymer A, and the preferred embodiment is also the same. Specific examples of the initiator having two or three hydroxyl groups are the same as those of the initiator of the polymer A.

The method for producing the polymer B is such that, after introducing one or more unsaturated groups into one main chain terminal of the precursor polymer and two or more in one molecule, the unsaturated group is reacted with a silylating agent. Is preferred.
When the precursor polymer has a hydroxyl group bonded to the terminal of the main chain, the polymer B can be produced also by a method of introducing a reactive silicon group via a bonding group that reacts with the hydroxyl group.

  As a method for producing the polymer B, conventionally known methods can be used. For example, JP-B-45-36319, JP-A-50-156599, JP-A-61-197631, and JP-A-319763. The methods proposed in JP-A-72527, JP-A-8-231707, U.S. Pat. No. 3,632,557, and U.S. Pat. No. 4,960,844 can be used without limitation.

The silylation ratio of the polymer B is preferably more than 50 mol% and 100 mol% or less, more preferably 55 to 97 mol%, and still more preferably 60 to 95 mol%.
When the curable composition of the present invention contains two or more types of polymer B, the average silylation rate of the entire polymer B may be within the above range.

<Polymer C>
In the curable composition of the present invention, the terminal group at one main chain terminal is an inactive monovalent organic group, and is represented by the above formula 1 on average to each main chain terminal in one molecule. An oxyalkylene polymer having more than 0 and 0.5 or less reactive silicon groups (hereinafter, referred to as “polymer C”) may be included. The polymer C has at least two main chain terminals, has at least one terminal group which is an inactive monovalent organic group in one molecule, and has an average number of terminal groups at each main chain terminal in one molecule. And has more than 0 reactive silicon groups and 0.5 or less.
When the polymer C has two main chain terminals, the total number of the reactive silicon groups that the polymer C has is divided by the number of terminal groups present in one molecule of the polymer C. It has more than 0 and less than 0.5 reactive silicon groups, and has 0.25 or more and 0.5 or less (that is, 0.5 or more and 1.0 or less reactive silicon groups per molecule) ), More preferably 0.3 or more and 0.5 or less (that is, 0.6 or more and 1.0 or less per molecule). In this case, of the two terminal groups of the polymer C, the terminal group that is neither an inert monovalent organic group nor the reactive silicon group is an active hydrogen-containing group or an unsaturated group. preferable.
When the polymer C has three main chain terminals, the total number of the reactive silicon groups that the polymer C has is divided by the number of terminal groups present in one molecule of the polymer C. It has more than 0 and less than 0.5 reactive silicon groups, and has 0.1 or more and 0.4 or less (that is, 0.3 or more and 1.2 or less reactive silicon groups per molecule) ) Is preferred, and more preferably 0.15 or more and 0.35 or less (that is, 0.45 or more and 1.05 or less per molecule). In this case, of the three terminal groups of the polymer C, the terminal group that is neither the inactive monovalent organic group nor the reactive silicon group is an active hydrogen-containing group or an unsaturated group. preferable.
The curable composition of the present invention may contain one kind of the polymer C or two or more kinds. The polymer C acts as a reactive plasticizer and contributes to lowering the viscosity of the curable composition and improving paint stainability.
Examples of the main chain of the polymer C are the same as those of the main chain of the polymer A.

Mn of the polymer C is preferably from 2,000 to 20,000, more preferably from 2,200 to 15,000, and still more preferably from 2,500 to 10,000. When the Mn of the polymer C is within the above range, the cured product has excellent elongation properties and the cured product has excellent paint stainability.
The molecular weight distribution of the polymer C is preferably 1.8 or less. From the viewpoint of viscosity reduction, the molecular weight distribution is preferably smaller, more preferably 1.6 or less, still more preferably 1.5 or less, and particularly preferably 1.4 or less.

The polymer C is obtained by averaging the reactive silicon group at the main chain terminal of the precursor polymer in which the terminal group at one main chain terminal is an inactive monovalent organic group with respect to one main chain terminal. Introduced so that more than 0 and 0.5 or less (that is, when divided by the total number of main chain terminals of one molecule, more than 0 and 0.5 or less in one molecule on average) What is obtained by is preferred.
The total number of divalent or higher valent atoms contained in one main chain terminal of polymer C is the same as that of polymer B, and the preferred range is also the same.
As the inactive monovalent organic group, R ¹⁰ —O— (R ¹⁰ is a monovalent hydrocarbon group) is preferable. R ¹⁰ is preferably a branched or straight-chain alkyl group having 1 to 20 carbon atoms, more preferably a branched or straight-chain alkyl group having 1 to 10 carbon atoms, and a branched or straight-chain alkyl group having 1 to 4 carbon atoms. Or a linear alkyl group is more preferable, and a methyl group, an ethyl group, an isopropyl group, an n-butyl group or a t-butyl group is particularly preferable.
The precursor of the polymer C can be produced in the same manner as the precursor of the polymer A, except that an initiator having one active hydrogen-containing group is used. One initiator may be used alone, or two or more initiators may be used in combination.
As the active hydrogen-containing group, a hydroxyl group is preferable.
As the initiator having one hydroxyl group, a monohydric alcohol having a linear or branched hydrocarbon group is preferable. Specifically, methanol, ethanol, 2-propanol, n-butyl alcohol, isobutyl alcohol, 2-butyl alcohol, t-butyl alcohol, 2-ethylhexanol, decyl alcohol, lauryl alcohol, tridecanol, cetyl alcohol, stearyl alcohol, Oleyl alcohol and low molecular weight polyoxyalkylene monol can be exemplified.

The polymer C has two main chain terminals in one molecule, and the terminal group at one main chain terminal is any of the reactive silicon group, active hydrogen-containing group, or unsaturated group, and Is preferably an inactive monovalent organic group derived from a residue obtained by removing one active hydrogen from the initiator.
The silylation rate of the polymer C is preferably 45 to 100 mol%, more preferably 50 to 97 mol%, and still more preferably 55 to 95%.
When the curable composition contains two or more polymers C, the average silylation rate in the entire polymer C may be within the above range.

<Other ingredients>
The curable composition of the present invention may contain other components other than the polymer A, the polymer B, the polymer C, and the silicon compound Z. Other components include a curing catalyst (silanol condensation catalyst), a filler, a plasticizer, a thixotropy-imparting agent, a stabilizer, an adhesion-imparting agent, a physical property modifier, a tackifying resin, a reinforcing material such as a filler, and a surface modification. Agents (surfactants), flame retardants, blowing agents, solvents, and silicates.
Other components are WO 2013/180203, WO 2014/192842, WO 2016/002907, JP-A-2014-88481, JP-A-2015-10162, and JP 2015, respectively. Conventionally known compounds described in JP-A-105293, JP-A-2017-039728, JP-A-2017-214541 and the like can be used in combination without limitation.

<Curable composition>
The amount of the polymer A contained in the curable composition of the present invention is preferably 1 to 80% by mass, more preferably 3 to 60% by mass, and more preferably 5 to 50% by mass based on the total mass of the curable composition. More preferred. When the amount of the polymer A is not less than the lower limit of the above range, good tensile properties are easily obtained, and when it is not more than the upper limit, good workability is easily obtained.
The total amount of the silicon compound Z contained in the curable composition of the present invention is at least 1.0 part by mass and less than 4.0 parts by mass with respect to 100 parts by mass of the polymer A, and 3.8 parts by mass is preferable, and 1.4 to 3.5 parts by mass is more preferable. When the amount is equal to or more than the lower limit of the above range, the surface tackiness of the cured product is easily suppressed, the effects of curability and fatigue resistance can be obtained in a well-balanced manner, and the effect of adding the silicon compound Z is sufficiently obtained. Cheap. When it is at most the upper limit of the above range, good curability is likely to be obtained.
When the curable composition of the present invention contains the polymer B, the content of the polymer B is preferably 5 to 500 parts by mass, more preferably 10 to 400 parts by mass, based on 100 parts by mass of the polymer A. And more preferably 15 to 300 parts by mass. When the content of the polymer B is equal to or more than the lower limit, good elongation properties are easily obtained. When the content of the polymer B is equal to or less than the upper limit, the curing speed is easily increased, and good durability is easily obtained.
When the curable composition contains the polymer C, the content of the polymer C is preferably from 1 to 600 parts by mass, and more preferably from 10 to 500 parts by mass, based on 100 parts by mass of the polymer A and the polymer B in total. More preferably, the amount is 15 to 300 parts by mass. When the content of the polymer C is equal to or more than the lower limit of the above range, the viscosity is reduced and the workability is excellent, and the paint stainability is improved. When the content is less than the upper limit, the fatigue resistance is excellent.

When the curable composition of the present invention contains the polymer A and the polymer B, the content ratio of each polymer is, when the total of the polymer A and the polymer B is 100% by mass, the polymer A / The polymer B is preferably from 5 to 95% by mass / 5 to 85% by mass, more preferably from 20 to 91% by mass / 9 to 80% by mass, and still more preferably from 25 to 87% by mass / 13 to 75% by mass. Preferably, 30 to 85% by mass / 15 to 70% by mass is particularly preferable, and 50 to 80% by mass / 20 to 50% by mass is most preferable. Within the above range, the elongation of the cured product becomes good, and the balance between the curability and the fatigue resistance tends to be good.
When the curable composition of the present invention contains the polymer A and the polymer C, the content ratio of each polymer is as follows: when the total of the polymer A and the polymer C is 100% by mass, As polymer C, it is preferably 10 to 99.5% by mass / 0.5 to 90% by mass, more preferably 15 to 99% by mass / 1 to 85% by mass, and more preferably 20 to 95% by mass / 5 to 80% by mass. % By mass is more preferable, 25 to 90% by mass / 10 to 75% by mass is particularly preferable, and 30 to 85% by mass / 15 to 70% by mass is most preferable. Within the above range, the elongation of the cured product becomes good, and the balance between the curability and the fatigue resistance tends to be good.
When the curable composition of the present invention contains the polymer A, the polymer B, and the polymer C, the content ratio of each polymer is 100% by mass of the total of the polymer A, the polymer B, and the polymer C. In this case, the polymer A / polymer B / polymer C is preferably 6 to 94% by mass / 5 to 82% by mass / 1 to 86% by mass, and more preferably 10 to 94% by mass / 5 to 60% by mass. % / 1 to 85% by mass, more preferably 30 to 90% by mass / 5 to 40% by mass / 5 to 50% by mass. When it is within the above range, the viscosity of the curable composition is lower, the elongation of the cured product is good, and the balance between curability and fatigue resistance tends to be good.

The curable composition of the present invention is obtained by mixing a polymer to be mixed with the curable composition and components other than the polymer.
The curable composition of the present invention may be a one-component type, in which all the components are preliminarily blended, sealed and stored, and cured by the moisture in the air after application, and may be a main component containing at least a component having a reactive silicon group. The composition may be of a two-component type in which the product and the curing agent composition containing at least the curing catalyst are separately stored, and the curing agent composition and the base composition are mixed before use.

The one-component curable composition preferably does not contain moisture. It is preferable to previously dehydrate and dry the blended components containing water, or to dehydrate under reduced pressure during blending and kneading.
In the two-component type curable composition, the curing agent composition may contain water, and the base composition does not easily gel even if it contains a small amount of water, but from the viewpoint of storage stability, the components are previously dehydrated and dried. Is preferred. In order to improve the storage stability, a conventionally known dehydrating agent such as a lower alcohol such as methanol or ethanol or an alkoxysilane can be added to the one-component type curable composition or the two-component type main composition.

  When the elasticity of the cured product of the curable composition of the present invention is evaluated by the maximum elongation, the maximum elongation is preferably 700% or more, more preferably 750% or more, further preferably 800% or more, and more preferably 850% or more. Particularly preferred. The upper limit of the maximum elongation is not particularly limited, and is, for example, about 1500%. When the content is within the above range, the material is suitable for the use described later.

The curable composition of the present invention may be used as a sealing material (for example, an elastic sealing material for building, a sealing material for double glazing, a sealing material for rust prevention / waterproofing of glass edges, a sealing material for backside of solar cells, a building material). A sealing material for objects, a sealing material for ships, a sealing material for automobiles, a sealing material for roads), an electrical insulating material (insulating coating material for electric wires and cables), and an adhesive are preferable.
In particular, it is suitable for applications in which the cured product is required to have elongation properties and repeated stretching durability, and examples thereof include a sealing material applied outdoors.

  Since the curable composition of the present invention contains the silicon compound Z in a specific amount, the curable composition is excellent in curability, has less stickiness on the surface of the cured product, and is excellent in fatigue resistance.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.
The following measurement method was used.
[Mn and molecular weight distribution]
Using Tosoh's HLC-8220GPC (product name), Mw and Mn in terms of polystyrene were measured using tetrahydrofuran as an eluent. Using these, the value of the molecular weight distribution (hereinafter, referred to as “Mw / Mn”) was calculated.

[Silylation rate]
In the method of introducing an unsaturated group using an allyl chloride at the main chain terminal, and reacting the silylating agent with the unsaturated group to introduce a reactive silicon group, the unsaturated group introduced at the main chain terminal, The charged equivalent (molar ratio) of the reactive silicon group of the silylating agent was defined as a silylation rate (mol%).
In the reaction between the unsaturated group introduced using allyl chloride and the silylating agent, the unsaturated group which does not react with the silylating agent due to a side reaction is about 10 mol%. Therefore, when less than 90 mol% of the unsaturated groups are reacted with the silylating agent, the above-mentioned equivalent charge becomes the silylation rate.

<Sticky evaluation method>
The curable composition obtained in each example was placed in a container having a length of 2.5 cm × a width of 6.0 cm × a depth of 1.2 cm, cured at a temperature of 23 ° C. and a humidity of 65% for 1 week, and further cured at a temperature of 50 ° C. and humidity Cured at 65% for one week to prepare a cured product to be used as a test body. The obtained cured product is cut into a size of 0.5 cm long × 0.5 cm wide × 1.2 cm deep, and the tack on the surface of the cured product is measured using a probe tack tester NR-500 (manufactured by Tester Sangyo Co., Ltd.). did. The measurement was performed under the conditions of a contact time of 10 seconds and a peeling speed of 1.0 cm / sec.
Excellent when the measured value is 1.5 or less because there is no surface stickiness (）), when it is 2.0 or less, good because the surface stickiness is small (少 な い), and when it is 2.0 or more, the surface is sticky. Therefore, it was determined to be defective (x).

<Evaluation of curability (consistency)>
450 g of the curable composition obtained in each example was put into a container (size: 10.5 cm long × 7.0 cm wide × 4.0 cm deep), and nitrogen gas was blown from the surface to remove bubbles. Thereafter, the container was placed in an atmosphere of 10 ° C. so as to be horizontal and cured for 40 hours to obtain a sample. The consistency of the sample was measured using an automatic penetration / penetration tester (RPM-101 type). In the measurement, a stainless cone-shaped cone (tip 0.38 mm) was penetrated with a load of 100 g into the center of the surface of the sample under a load of 100 g, and the length penetrated for 5 seconds (penetration depth, unit: mm) ) Was measured, and the value obtained by multiplying the penetration depth by 10 was taken as the value of the consistency.
When the consistency value is 70 or less, the curability is excellent (◎). When the consistency value is 90 or less, the curability is good (○). When the consistency value is more than 90, the curability is normal (超). Sometimes the curability was determined to be poor (x).

<Fatigue resistance (durability) test method>
The test was performed according to the fatigue resistance classification CR90 in the fatigue resistance test described in 5.22 of JIS A 1439 (2016). As the adherend, surface anodized aluminum whose surface was treated with a primer (MP-2000 (product name), manufactured by Cemedine Co., Ltd.) was used.
A crack in the cured product was observed near the bonding interface between the adherend and the cured product every 500 times of stretching, and the number of stretching when the crack reached 2.5 mm or more was recorded. The greater the number of times of expansion and contraction, the better the fatigue resistance.
Excellent fatigue resistance when the number of expansions and contractions at the time is 5,000 or more (A), good fatigue resistance when the number of expansions and contractions is 4,000 or more (O), and 4,000 or less The fatigue resistance was determined to be normal (、) and the fatigue resistance was determined to be poor (×) when the fatigue resistance was 3,000 or less.

<Evaluation of tensile properties (H-type test)>
As an adherend, an H-type test piece was used in accordance with JIS A 1439, a method for testing a sealing material for building, using surface anodized aluminum having a surface treated with a primer (product name: MP-2000, manufactured by Cemedine Co., Ltd.). Was prepared and a tensile property test was performed.
Specifically, the prepared H-type specimen was cured at a temperature of 23 ° C. and a humidity of 65% for one week, and further cured at a temperature of 50 ° C. and a humidity of 65% for a week to prepare a cured product of the H-type specimen. . The cured product was measured for tensile properties (H-type properties) using a Tensilon tester, and the maximum elongation (unit:%) was measured. The larger the value of the maximum point elongation, the better the elongation.

<Paint contamination>
The curable composition was poured into a frame having a shape of 50 mm long, 50 mm wide and 10 mm thick placed on an aluminum plate, cured at 23 ° C. and 50% humidity for 48 hours and cured. 0.1 ml of a one-component aqueous reaction-curable silicone resin paint (Odefresh Si100II, product name of Nippon Paint Co., Ltd.) was applied on the cured product. Next, it was dried at 23 ° C. and a humidity of 50% for 3 days, further cured at 90 ° C. for 1 week, and left standing at 23 ° C. for 1 day. On the surface of the cured product, 0.5 g of the well-dried contaminated powder was sprinkled over the entire surface, allowed to stand for 10 minutes, and then the non-adhered contaminated powder was sieved off. It is excellent that the color of the cured product is maintained with almost no adhesion of contaminant powder on the surface of the cured product (◎), and that the color of the cured product is slightly adhered but the color of the cured product is good (◎) ）), Those with a large amount of contaminated powder adhering and impaired color of the cured product were judged to be defective (x). In addition, 1,8 kinds of JIS test powder (Kanto Rohm) (Japan Powder Industry Association) were used as the contaminated powder.

(Synthesis Example 1: Polymer A1)
Polyoxypropylene glycol having Mn of about 2,000 and having two terminal hydroxyl groups is used as an initiator, and a ligand is a zinc hexacyanocobaltate complex of t-butyl alcohol (hereinafter referred to as a TBA-DMC catalyst). Was used as a catalyst to polymerize propylene oxide to obtain an oxypropylene polymer (precursor polymer q1). The precursor polymer q1 had hydroxyl groups at both ends, Mn was 22,000, and Mw / Mn was 1.07.
A methanol solution in which the concentration of 1.15 molar equivalents of sodium methoxide relative to the hydroxyl groups of the obtained precursor polymer q1 was 28% by mass was added. After methanol was distilled off under reduced pressure, 1.05 molar equivalent of allyl glycidyl ether was added to the hydroxyl group of the precursor polymer q1, and the mixture was reacted at 130 ° C. for 2 hours. Thereafter, a methanol solution of 0.28 molar equivalent of sodium methoxide was added to remove methanol, and an excess amount (2.10 molar equivalents) of allyl chloride was added to the amount of hydroxyl groups of the precursor polymer q1. The reaction was carried out at 130 ° C. for 2 hours to convert the terminal group into an allyl group, and unreacted allyl chloride was removed from the system under reduced pressure to obtain a reaction solution containing NaCl as a by-product salt in the system.
Next, 1 part by mass of a block copolymer of an ethylene oxide monomer and a propylene oxide monomer and 5 parts by mass of water are added to 100 parts by mass of the reaction solution, and a liquid temperature of 80 ° C. is added under a nitrogen atmosphere. Then, NaCl as a by-product salt was extracted with water.
Next, while flowing nitrogen into the reactor, the mixture was heated to 80 ° C. and kept for 5 hours to evaporate water to precipitate NaCl crystals, followed by filtration. The obtained filtrate was dehydrated under reduced pressure. Thus, an oxypropylene polymer (polymer Q1) having an allyl group introduced into the main chain terminal was obtained. The average number of allyl groups introduced into one main chain terminal of the polymer Q1 was 2.0.

Then, in the presence of a platinum divinyldisiloxane complex, 0.70-fold molar equivalent of dimethoxymethylsilane with respect to the allyl group of the polymer Q1 was added as a silylating agent and reacted at 70 ° C for 5 hours. The dimethoxymethylsilane of the reaction was removed under reduced pressure to obtain a polymer (polymer A1) having a dimethoxymethylsilyl group introduced as a reactive silicon group at the terminal of the main chain.
For the obtained polymer A1, Mn, Mw / Mn, the silylation rate, the average number of reactive silicon groups per molecule calculated based on the silylation rate, and the reactive silicon group per one main chain terminal Are shown in Table 3. Table 3 also shows the characteristics of the following polymers.

(Synthesis Example 2: Polymer A2)
After obtaining the polymer Q1 in the same manner as in Synthesis Example 1, in the presence of a platinum divinyldisiloxane complex, 0.80 moles of dimethoxymethylsilane was added as a silylating agent to the allyl group of the polymer Q1, After reacting at 70 ° C. for 5 hours, unreacted dimethoxymethylsilane was removed under reduced pressure to obtain a polymer having a dimethoxymethylsilyl group introduced into a main chain terminal (polymer A2).

(Synthesis Example 3: Polymer A3)
After obtaining the polymer Q1 in the same manner as in Synthesis Example 1, in the presence of a platinum divinyldisiloxane complex, 0.60 moles of dimethoxymethylsilane with respect to the allyl group of the polymer Q1 was added as a silylating agent, After reacting at 70 ° C. for 5 hours, unreacted dimethoxymethylsilane was removed under reduced pressure to obtain a polymer (polymer A3) having a dimethoxymethylsilyl group introduced into a main chain terminal.

(Synthesis Example 4: Polymer A4)
Except for adjusting the amount of propylene oxide to be polymerized, a polyoxypropylene having Mn of 17,000 and having hydroxyl groups at both ends was obtained in the same manner as in Synthesis Example 1. Mw / Mn was 1.06. In the same manner as in Synthesis Example 1, the end group of the obtained polyoxypropylene was converted to an allyl group, and a 0.70-fold molar amount of a silylating agent was reacted with respect to the allyl group to form a dimethoxymethylsilyl group. A polymer (polymer A4) introduced into the main chain terminal was obtained.

(Synthesis Example 5: Polymer A5)
A polyoxypropylene having Mn of 24,000 and having hydroxyl groups at both terminals was obtained in the same manner as in Synthesis Example 1 except that the amount of propylene oxide to be polymerized was adjusted. Mw / Mn was 1.08. In the same manner as in Synthesis Example 1, the terminal group of the obtained polyoxypropylene was converted to an allyl group, and a 0.80-fold molar amount of a silylating agent was reacted with respect to the allyl group to form a dimethoxymethylsilyl group. A polymer (polymer A5) introduced into the main chain terminal was obtained.

(Synthesis example 6: polymer A6)
Mn was about 29,000 as in Synthesis Example 1 except that Mn was about 330, polyoxypropylene triol having three terminal hydroxyl groups was used as an initiator, and the amount of propylene oxide to be polymerized was adjusted. An oxypropylene polymer having three hydroxyl groups per chain terminal was obtained. Mw / Mn was 1.17. In the same manner as in Synthesis Example 1, the terminal group of the obtained oxypropylene polymer was converted to an allyl group, and a 0.80-fold molar amount of a silylating agent was reacted with respect to the allyl group to obtain a dimethoxymethylsilyl group. Was obtained at the main chain terminal (polymer A6).

(Synthesis example 7: polymer B1)
In the same manner as in Synthesis Example 1, an oxypropylene polymer (precursor polymer q2) having hydroxyl groups at both ends, Mn of 22,000 and Mw / Mn of 1.07 was obtained.
A methanol solution of 28% by mass of sodium methoxide in an amount of 1.15 mol equivalent to the hydroxyl group of the obtained precursor polymer q2 was added. After distilling off methanol under reduced pressure, 1.5 molar equivalents of allyl chloride were added to the hydroxyl groups of the precursor polymer q2, and reacted at 130 ° C. for 2 hours to convert the terminal groups to allyl groups. An oxypropylene polymer (polymer Q2) was obtained. The average number of allyl groups introduced into one main chain terminal of polymer Q2 was 1.0.

Then, in the presence of a platinum divinyldisiloxane complex, 0.80 moles of dimethoxymethylsilane was added as a silylating agent to the allyl group of the polymer Q2, and reacted at 70 ° C for 5 hours. Was removed under reduced pressure to obtain a polymer (polymer B1) in which a dimethoxymethylsilyl group was introduced as a reactive silicon group at the terminal of the main chain. ^The polymer B1 had an average of 0.8 dimethoxymethylsilyl groups at one terminal as measured by ¹ H-NMR.

(Synthesis Example 8: Polymer B2)
Same as Synthesis Example 7 except that the amount of propylene oxide to be polymerized is adjusted using polyoxypropylene triol (molecular weight per functional group: 330) obtained by subjecting propylene oxide to ring-opening addition polymerization of glycerin as an initiator. Thus, an oxypropylene polymer (precursor polymer q3) was obtained. The obtained precursor polymer q3 had three hydroxyl groups per molecule at the terminal of the main chain, Mn was 29,000, and Mw / Mn was 1.17.
Next, allylation was performed on the terminal group of the precursor polymer q3 in the same manner as in Synthesis Example 7 to obtain an oxypropylene polymer having three allyl groups per molecule at the main chain terminal (polymer Q3). .
Next, silylation was performed on the allyl group of the polymer Q3 in the same manner as in Synthesis Example 7 to obtain an oxypropylene polymer (polymer B2) having an average of 0.8 dimethoxymethylsilyl groups at one terminal site. .

(Synthesis Example 9: Polymer C1)
A precursor polymer c1 having Mn of 7,500 was obtained in the same manner as in Synthesis Example 1 except that n-butyl alcohol was used as an initiator and the amount of propylene oxide to be polymerized was adjusted. The terminal group on the hydroxyl group side of the precursor polymer c1 was converted to an allyl group, and dimethoxymethylsilane was added as a silylating agent in an amount 0.80 times the mol of the allyl group, followed by reaction at 70 ° C. for 5 hours. A polyoxypropylene polymer (polymer C1) having a dimethoxymethylsilyl group introduced into the main chain terminal as a silicon group was obtained.

(Other components)
The additives described in Table 1 are as follows.
White glossy CCR: Colloidal calcium carbonate, product name of Shiraishi Industry Co., Ltd.
Whiten SB: heavy calcium carbonate having an average particle size of 1.78 μm, a product name of Shiraishi Industry Co., Ltd.
Titanium oxide R820: titanium oxide, product name of Ishihara Sangyo Co., Ltd.
Balloon 80GCA: Organic balloon, product name of Matsumoto Yushi Co., Ltd.
Balloon 81GCA: Organic balloon, product name of Matsumoto Yushi Co., Ltd.
PMLS4012: Preminol S4012, a high molecular weight polyol having two hydroxyl groups per molecule and Mn of 13,000, a product name of Asahi Glass Co., Ltd.
DIDP (abbreviation): diisodecyl phthalate, manufactured by Mitsubishi Chemical Corporation.
DINP (abbreviation): Diisononyl phthalate, SANSOSIZER DINP, product name of Shin Nippon Rika Co., Ltd.
Sansocizer EPS: 4,5-epoxycyclohexane-1,2-dicarboxylic acid-di-2-ethylhexyl, a product name of Shin Nippon Rika Co., Ltd.
Dispalon # 305: Hydrogenated castor oil-based thixotropic agent, Kusumoto Chemicals product name.
Dispalon # 308: Hydrogenated castor oil-based thixotropic agent, Kusumoto Chemicals product name.
M-309: Aronix M-309: Photocurable resin, product name of Toagosei Co., Ltd.
Tung oil: made by Kimura Corporation.
IRGANOX1135: hindered phenolic antioxidant, product name of BASF.
TINUVIN 326: benzotriazole-based ultraviolet absorber, BASF product name.
TINUVIN 765: hindered amine light stabilizer containing tertiary amine, product name of BASF.
TINUVIN 770: hindered amine light stabilizer containing secondary amine, product name of BASF.
KBM-403: 3-glycidyloxypropyltrimethoxysilane, a product name of Shin-Etsu Chemical Co., Ltd.

Catalyst A is a composition obtained by mixing the following components at the mass ratios shown in Table 2.
Curing catalyst: a mixture of stanoct and laurylamine mixed at a mass ratio of 6: 1.
Stanocto: Stannous octylate, product name of Mitsubishi Chemical Corporation.
Whiteton SB: As described above.
Glomax LL: calcined kaolin, product name of Takehara Chemical Industries.

<Preparation of curable composition>
Examples 13 to 15 in Table 4 are Examples, Examples 1 to 12 in Table 4 and 31 to 39 in Table 6 are Reference Examples , and Examples 16 to 24 in Table 5 are Comparative Examples.
A curable composition was prepared by mixing a polymer having reactive silicon having the composition shown in Tables 4 to 6, the silicon compound Z, and each component having the composition shown in Tables 1 and 2.
In Tables 4 to 6, "TMP-3TMS" is a tristrimethylsilyl derivative of trimethylolpropane, and "Phenoxysilane" is phenoxytrimethylsilane.
Each test described above was performed on the cured product of the obtained curable composition. The results are shown in Tables 4 to 6.
In addition, the curable compositions of Examples 25 to 30, which are not shown in the tables, were prepared by changing Formulation 1 of the additive compounding formulation in Table 4 in Examples 1 and 9 to Formulations 3 to 5 described in Table 1, respectively. Obtained. Examples 25 to 30 are reference examples . Examples 25 and 26 are examples in which Formulation 3 described in Table 1 was added, Examples 27 and 28 were examples in which Formulation 4 described in Table 1 was added, and Examples 29 and 30 were compositions in which Formulation 3 described in Table 1 was added. This is an example in which 5 is added. The obtained curable composition is placed in a container having a length of 2.5 cm × a width of 6.0 cm × a depth of 1.2 cm, cured for one week at a temperature of 23 ° C. and a humidity of 65%, and further cured at a temperature of 50 ° C. and a humidity of 65%. Cured for one week to obtain a cured product. In all of Examples 25 to 30, curing was excellent.

Examples 1 to 15 and Examples 31 to 39 in which the total mass of the silicon compound Z contained in the curable composition is 1.0 part by mass or more and less than 4.0 parts by mass with respect to 100 parts by mass of the polymer A, The curability (consistency) is excellent (◎) or good (○), and the surface of the cured product is excellent (◎) or good (○), and the fatigue resistance is excellent (◎) or good. (○).
In Examples 1, 5, 14 and 15, the paint stain was also excellent (優秀) or good (○).
In Examples 16 and 17 in which the total mass of the silicon compound Z contained in the curable composition was less than 1.0 part by mass with respect to 100 parts by mass of the polymer A, the surface tackiness of the cured product was poor (x). Was.
In Example 18, in which the total mass of the silicon compound Z contained in the curable composition is 4.0 parts by mass or more based on 100 parts by mass of the polymer A, curing is insufficient, and a cured product suitable for a test is obtained. I couldn't do that.
In Example 19 in which the curable composition did not contain the polymer A but only the polymer B1, the curing was insufficient, and a cured product suitable for the test could not be obtained.
For Examples 18 and 19 with insufficient curing, it was clear that the surface was not sticky (x).
In Examples 20 to 24 in which the curable composition did not contain the polymer A but only the polymer B2, all of the curability, stickiness, and fatigue resistance could not be satisfied.
From the above, it can be seen that the curable composition according to the present invention is excellent in curability, has little stickiness on the surface of the cured product, and is excellent in fatigue resistance.

Claims (9)

The terminal group at the terminal of the main chain is any of a reactive silicon group, an active hydrogen-containing group or an unsaturated group represented by the following formula 1, and the number of active hydrogen-containing groups contained in one molecule is averaged. Less than or equal to 0.3, having an average of more than 1.0 of the reactive silicon groups at one main chain terminal, and a ratio of the number of the reactive silicon groups to the total of the terminal groups. silylation of 50 mole percent represented state, and are less 97 mol%, and the oxyalkylene polymer A is a number average molecular weight of 4,000～50,000 and molecular weight distribution of 1.20 or less,
The terminal group at the terminal of the main chain is any of a reactive silicon group, an active hydrogen-containing group or an unsaturated group represented by the following formula 1, and is represented by the following formula 1 on average at one main chain terminal An oxyalkylene polymer B having more than 0.5 and not more than 1.0 reactive silicon groups,
A silicon compound that produces a silanol represented by the following formula Z by hydrolysis :
Per 100 parts by mass of pre-Symbol oxyalkylene polymer A, it contains less than 1.2 part by weight to 4.0 parts by weight of the silicon compound, the curable composition.
—SiX _a R _3-a (Formula 1)
L ₃ SiOH (Formula Z)
[In the formula 1, R is a monovalent organic group having 1 to 20 carbon atoms and represents an organic group other than a hydrolyzable group, and X represents a hydroxyl group or a hydrolyzable group. a is an integer of 1 to 3. When a is 1, R may be the same or different. When a is 2 or more, Xs may be the same or different. In Formula Z, L independently represents a substituted or unsubstituted monovalent hydrocarbon group or a hydrogen atom. ]   The terminal group at one main chain terminal is an inactive monovalent organic group, and more than 0 reactive silicon groups represented by the above formula 1 are averaged at each main chain terminal in one molecule. The curable composition according to claim 1, further comprising an oxyalkylene polymer C having 5 or less.   The terminal group at the terminal of the main chain is any of a reactive silicon group, an active hydrogen-containing group or an unsaturated group represented by the following formula 1, and the number of active hydrogen-containing groups contained in one molecule is averaged. Less than or equal to 0.3, and having an average of more than 1.0 of the reactive silicon groups at one main chain terminal, and a ratio of the number of the reactive silicon groups to the total of the terminal groups. An oxyalkylene polymer A having a expressed silylation ratio of more than 50 mol% and 97 mol% or less, a number average molecular weight of 4,000 to 50,000 and a molecular weight distribution of 1.20 or less;
  The terminal group at one main chain terminal is an inactive monovalent organic group, and more than 0 reactive silicon groups represented by the following formula 1 are averaged at each main chain terminal in one molecule. An oxyalkylene polymer C having 5 or less,
  A silicon compound that produces a silanol represented by the following formula Z by hydrolysis:
  A curable composition comprising 1.2 parts by mass or more and less than 4.0 parts by mass of the silicon compound based on 100 parts by mass of the oxyalkylene polymer A.
  -SiX _a R _3-a     (Equation 1)
  L ₃ SiOH (Formula Z)
[In the formula 1, R is a monovalent organic group having 1 to 20 carbon atoms and represents an organic group other than a hydrolyzable group, and X represents a hydroxyl group or a hydrolyzable group. a is an integer of 1 to 3. When a is 1, R may be the same or different. When a is 2 or more, Xs may be the same or different. In the formula Z, L independently represents a substituted or unsubstituted monovalent hydrocarbon group or a hydrogen atom. ] The curable composition according to any one of claims 1 to 3, wherein at least one main chain terminal of the oxyalkylene polymer A is an atomic group represented by the following formula 2.

[Wherein, R ¹ and R ³ each independently represent a divalent bonding group having 1 to 6 carbon atoms, and the atoms bonded to the carbon atoms in the bonding group are a carbon atom, a hydrogen atom, an oxygen atom, It is a nitrogen atom or a sulfur atom. R ² and R ⁴ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. n shows the integer of 1-10. R ⁵ is each independently a monovalent organic group having 1 to 20 carbon atoms, and represents an organic group other than a hydrolyzable group, and Y each independently represents a hydroxyl group or a hydrolyzable group. b is an integer of 1 to 3. When a plurality of R ⁵ are present, R ⁵ may be the same or different from each other. When a plurality of Ys are present, the Ys may be the same or different. ] The curing according to any one of claims 1 to 4 , wherein the content of the silicon compound is 2.5 parts by mass or more and less than 4.0 parts by mass with respect to 100 parts by mass of the oxyalkylene polymer A. Composition. The oxyalkylene polymer A has two main chain terminals in one molecule, and is a reactive silicon group, an active hydrogen-containing group or an unsaturated group represented by the formula 1 at each main chain terminal. The curable composition according to any one of claims 1 to 5 , which has two terminal groups.   The silicon compound according to any one of claims 1 to 6, wherein the silicon compound is at least one selected from the group consisting of phenoxytrimethylsilane, trimethylolpropane tris (trimethylsilyl) ether, tetramethyldisilazane, and hexamethyldisilazane. The curable composition according to the above.   The curable composition according to any one of claims 1 to 7, which is used for a sealing material.   A cured product of the curable composition according to claim 1.