JP7404105B2 - curable composition - Google Patents

Description

The present invention relates to a multi-component curable composition.

In order to reduce the weight of vehicles, aircraft, and railways, structural members are increasingly being replaced with lightweight materials other than steel, such as aluminum, magnesium, and carbon fiber composite materials. It is increasing. Since spot welding and laser welding can sometimes be difficult to join dissimilar materials, adhesive joining using adhesives is attracting attention. Steel plates, aluminum alloys, and fiber-reinforced composites each have different coefficients of linear expansion, so the adhesive is required to have flexibility that can follow thermal distortion. For this reason, the high rigidity of epoxy resins can be disadvantageous, and there is a need for new structural adhesives that have high modulus and flexibility.

As adhesives, compositions made of reactive silicon group-containing polyoxyalkylene polymers and epoxy resins that have both high strength at break and flexibility are known (see, for example, Patent Document 1); In some cases, the adhesive did not have sufficient strength.

On the other hand, in Patent Document 2, agent A contains a polyoxyalkylene polymer having more than one reactive silicon group at one end, a reactive silicon group-containing (meth)acrylic acid ester polymer, It is disclosed that a multi-component curable composition containing Part B containing an epoxy resin forms a cured product exhibiting high strength, high rigidity, and flexibility, and can be used as a structural adhesive.

Japanese Patent Application Publication No. 02-214759 International Publication No. 2019/069866

It is desirable that the curable composition has high thixotropy from the viewpoint of workability during construction. Furthermore, the elastic modulus of a cured product obtained by curing the curable composition depends on the environmental temperature, and in conventional compositions, the elastic modulus tends to decrease significantly when the environmental temperature becomes high. Since the temperature range of actual use is wide, it is desirable that the elastic modulus decreases little at high temperatures.

In view of the above-mentioned current situation, the present invention provides a curable composition that exhibits high thixotropy and can provide a cured product with suppressed decline in elastic modulus at high temperatures, and a cured product obtained by curing the composition. The purpose is to provide

As a result of extensive studies to solve the above problems, the present inventors have developed a reactive silicon group-containing polyoxyalkylene polymer, a reactive silicon group-containing (meth)acrylate ester polymer, and an epoxy resin. The present inventors have discovered that the above-mentioned problems can be solved by using a plurality of specific epoxy resins and a specific filler in a multi-component curable composition containing the same, and have completed the present invention.

（式中、Ｒ^１，Ｒ^３はそれぞれ独立に２価の炭素数１～６の結合基であり、Ｒ^１，Ｒ^３に隣接するそれぞれの炭素原子と結合する原子は、炭素、酸素、窒素のいずれかである。Ｒ^２，Ｒ^４はそれぞれ独立に水素、または炭素数１～１０の炭化水素基である。ｎは１～１０の整数である。Ｒ^５は、置換又は非置換の炭素数１～２０の炭化水素基である。Ｘは水酸基または加水分解性基である。ｃは０または１を示す。）で表される。
好ましくは、Ｒ^１がＣＨ_２ＯＣＨ_２であり、Ｒ^３がＣＨ_２である。
好ましくは、Ｒ^２及びＲ^４がそれぞれ水素原子である。
好ましくは、（メタ）アクリル酸エステル系重合体（Ｂ）が、反応性ケイ素基と重合性不飽和基を有する単量体（ｂ１）、及び重合性不飽和基を有する（メタ）アクリル酸エステル系重合体であるマクロモノマー（ｂ２）を構成単量体とする重合体である。
好ましくは、前記アミノフェノール型エポキシ樹脂が、トリグリシジルｐ－アミノフェノールである。
好ましくは、前記ナフタレン型エポキシ樹脂が、１，６－ビス（グリシジルオキシ）ナフタレンである。
また本発明は、前記多液型の硬化性組成物からなる構造用接着剤にも関する。
さらに本発明は、前記多液型の硬化性組成物を硬化させて得られる硬化物にも関する。 That is, the present invention provides a polyoxyalkylene polymer (A) having a reactive silicon group represented by the general formula (1), a (meth)acrylic acid ester polymer having a reactive silicon group represented by the general formula (1) (B) and an epoxy resin curing agent (D) having a tertiary amine; and a B agent containing an epoxy resin (C). The resin (C) contains a bisphenol A-type epoxy resin (C1) and an aminophenol-type epoxy resin and/or a naphthalene-type epoxy resin (C2), and either or both of the A agent and the B agent are fumed silica. The present invention relates to a multi-component curable composition containing (E).
-SiR ⁵ _c X _3-c (1)
(In the formula, R ⁵ is a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. X represents a hydroxyl group or a hydrolyzable group. c represents 0 or 1.)
Preferably, the reactive silicon group of the polyoxyalkylene polymer (A) is a trimethoxysilyl group.
Preferably, the reactive silicon group of the (meth)acrylic acid ester polymer (B) is a trimethoxysilyl group.
Preferably, the terminal portion of the polyoxyalkylene polymer (A) has the general formula (2):

(In the formula, R ¹ and R ³ are each independently a divalent bonding group having 1 to 6 carbon atoms, and the atoms bonded to each carbon atom adjacent to R ¹ and R ³ are carbon, oxygen, nitrogen, R ² and R ⁴ are each independently hydrogen or a hydrocarbon group having 1 to 10 carbon atoms. n is an integer of 1 to 10. R ⁵ is a substituted or unsubstituted carbon It is a hydrocarbon group of numbers 1 to 20. X is a hydroxyl group or a hydrolyzable group. c represents 0 or 1).
Preferably R ¹ is CH ₂ OCH ₂ and R ³ is CH ₂ .
Preferably, R ² and R ⁴ are each a hydrogen atom.
Preferably, the (meth)acrylic ester polymer (B) includes a monomer (b1) having a reactive silicon group and a polymerizable unsaturated group, and a (meth)acrylic ester having a polymerizable unsaturated group. This is a polymer whose constituent monomer is macromonomer (b2), which is a system polymer.
Preferably, the aminophenol type epoxy resin is triglycidyl p-aminophenol.
Preferably, the naphthalene type epoxy resin is 1,6-bis(glycidyloxy)naphthalene.
The present invention also relates to a structural adhesive comprising the multi-component curable composition.
Furthermore, the present invention also relates to a cured product obtained by curing the multi-component curable composition.

According to the present invention, there is provided a curable composition that exhibits high thixotropy and can provide a cured product with suppressed decrease in elastic modulus at high temperatures, and a cured product obtained by curing the composition. be able to.

Embodiments of the present invention will be specifically described below, but the present invention is not limited to these embodiments.

<<Polyoxyalkylene polymer (A) having reactive silicon group>>
<Reactive silicon group>
The polyoxyalkylene polymer (A) has a reactive silicon group represented by the general formula (1).
-SiR ⁵ _c X _3-c (1)
(In the formula, R ⁵ is a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. X represents a hydroxyl group or a hydrolyzable group. c represents 0 or 1.)

The number of carbon atoms in the hydrocarbon group of R ⁵ is preferably 1 to 10, more preferably 1 to 5, and even more preferably 1 to 3. Specific examples of R ⁵ include, for example, a methyl group, an ethyl group, a chloromethyl group, a methoxymethyl group, and an N,N-diethylaminomethyl group, but preferably a methyl group, an ethyl group, and a chloromethyl group. and methoxymethyl group, more preferably methyl group and methoxymethyl group.

Examples of X include hydroxyl group, halogen, alkoxy group, acyloxy group, ketoximate group, amino group, amide group, acid amide group, aminooxy group, mercapto group, and alkenyloxy group. Among these, alkoxy groups such as a methoxy group and an ethoxy group are more preferable, and a methoxy group and an ethoxy group are particularly preferable because they are mildly hydrolyzable and easy to handle.

Specifically, the reactive silicon group possessed by the polyoxyalkylene polymer (A) includes a trimethoxysilyl group, a triethoxysilyl group, a tris(2-propenyloxy)silyl group, a triacetoxysilyl group, and a dimethoxymethyl group. Silyl group, diethoxymethylsilyl group, dimethoxyethylsilyl group, (chloromethyl)dimethoxysilyl group, (chloromethyl)diethoxysilyl group, (methoxymethyl)dimethoxysilyl group, (methoxymethyl)diethoxysilyl group, (N , N-diethylaminomethyl)dimethoxysilyl group, (N,N-diethylaminomethyl)diethoxysilyl group, and the like, but are not limited to these. Among these, methyldimethoxysilyl group, trimethoxysilyl group, triethoxysilyl group, (chloromethyl)dimethoxysilyl group, (methoxymethyl)dimethoxysilyl group, (methoxymethyl)diethoxysilyl group, (N,N- Diethylaminomethyl) dimethoxysilyl group is preferred because it exhibits high activity and can yield a cured product with good mechanical properties, and trimethoxysilyl group and triethoxysilyl group are more preferred because they yield a highly rigid cured product. More preferred is a trimethoxysilyl group.

The polyoxyalkylene polymer (A) may have more than one reactive silicon group on average at one terminal site. Having more than one reactive silicon group on average at one terminal site means that the polyoxyalkylene polymer (A) has two or more reactive silicon groups at one terminal site as shown in the following general formula (2). This indicates that polyoxyalkylene having more than one reactive silicon group is included. That is, the polyoxyalkylene polymer (A) may contain only polyoxyalkylene having two or more reactive silicon groups at one terminal site, or may contain only polyoxyalkylene having two or more reactive silicon groups at one terminal site. It may contain both a polyoxyalkylene having a reactive silicon group and a polyoxyalkylene having one reactive silicon group at one terminal site. In addition, as the plurality of terminal moieties that one molecule of polyoxyalkylene has, there may be both a terminal moiety having two or more reactive silicon groups and a terminal moiety having one reactive silicon group. Furthermore, the polyoxyalkylene polymer (A) as a whole has more than one reactive silicon group on average at one terminal site, but the polyoxyalkylene polymer (A) has a terminal site having no reactive silicon group. It may also contain oxyalkylene.

(In the formula, R ¹ and R ³ are each independently a divalent bonding group having 1 to 6 carbon atoms, and the atoms bonded to each carbon atom adjacent to R ¹ and R ³ are carbon, oxygen, nitrogen, R ² and R ⁴ are each independently hydrogen or a hydrocarbon group having 1 to 10 carbon atoms. n is an integer of 1 to 10. R ⁵ , X, and c are represented by the formula (1 ) as described above.)

R ¹ and R ³ may be a divalent organic group having 1 to 6 carbon atoms, or a hydrocarbon group which may contain an oxygen atom. The hydrocarbon group preferably has 1 to 4 carbon atoms, more preferably 1 to 3 carbon atoms, and even more preferably 1 to 2 carbon atoms. Specific examples of R ¹ include, for example, CH ₂ OCH ₂ , CH ₂ O, and CH ₂ , and preferably CH ₂ OCH ₂ . Specific examples of R ³ include, for example, CH ₂ and CH ₂ CH ₂ , preferably CH ₂ .

The number of carbon atoms in the hydrocarbon group of R ² and R ⁴ is preferably 1 to 5, more preferably 1 to 3, and even more preferably 1 to 2. Specific examples of R ² and R ⁴ include, for example, a hydrogen atom, a methyl group, and an ethyl group, preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom.

According to a particularly preferred embodiment of the terminal portion represented by general formula (2), R ¹ is CH ₂ OCH ₂ , R ³ is CH ₂ , and R ² and R ⁴ are each a hydrogen atom. n is preferably an integer of 1 to 5, more preferably 1 to 3, and even more preferably 1 or 2. However, n is not limited to one value, and may be a mixture of a plurality of values.

The polyoxyalkylene polymer (A) preferably has an average of more than 1.0 reactive silicon groups per terminal site, more preferably 1.1 or more. , more preferably 1.5 or more, even more preferably 2.0 or more. Moreover, it is preferable that it is 5 or less, and it is more preferable that it is 3 or less.

The number of terminal moieties having more than one reactive silicon group contained in one molecule of the polyoxyalkylene polymer (A) is preferably 0.5 or more on average, and 1.0 It is more preferable that the number is 1.1 or more, even more preferably 1.5 or more. Moreover, it is preferable that it is 4 or less, and it is more preferable that it is 3 or less.

The polyoxyalkylene polymer (A) may have reactive silicon groups in areas other than the terminal parts, but having them only in the terminal parts makes it possible to obtain a rubber-like cured product with high elongation and low elastic modulus. This is preferable because it makes it easier to

The average number of reactive silicon groups per molecule of the polyoxyalkylene polymer (A) is preferably more than 1.0, more preferably 1.2 or more, further preferably 1.3 or more. It is preferably 1.5 or more, even more preferably 1.7 or more. Further, the number is preferably 6.0 or less, more preferably 5.5 or less, and most preferably 5.0 or less. If the average number of reactive silicon groups per molecule is 1.0 or less, a cured product with high strength may not be obtained. If the average number of reactive silicon groups per molecule exceeds 6.0, a cured product with high elongation may not be obtained.

<Main chain structure>
The main chain skeleton of the polyoxyalkylene polymer (A) is not particularly limited, and examples thereof include polyoxyethylene, polyoxypropylene, polyoxybutylene, polyoxytetramethylene, polyoxyethylene-polyoxypropylene copolymer, Examples include polyoxypropylene-polyoxybutylene copolymer. Among them, polyoxypropylene is preferred.

The number average molecular weight of the polyoxyalkylene polymer (A) is 3,000 to 100,000, more preferably 3,000 to 50,000, particularly preferably 3,000 to 30, in terms of polystyrene equivalent molecular weight in GPC. It is 000. If the number average molecular weight is less than 3,000, a large amount of reactive silicon groups will be introduced, which may be inconvenient in terms of manufacturing costs, and if it exceeds 100,000, the viscosity will be high, resulting in poor workability. There is an inconvenient tendency.

The molecular weight of the polyoxyalkylene polymer (A) is determined by measuring the hydroxyl value of the organic polymer precursor before introduction of reactive silicon groups using the hydroxyl value measurement method specified in JIS K 1557 and the iodine value measurement method specified in JIS K 0070. Directly measure the terminal group concentration by titration analysis based on the principle of the measurement method, and express it as the terminal group equivalent molecular weight determined by taking into account the structure of the organic polymer (branching degree determined by the polymerization initiator used). You can also do it. The molecular weight in terms of terminal groups of the polyoxyalkylene polymer (A) was determined by creating a calibration curve between the number average molecular weight determined by general GPC measurement of an organic polymer precursor and the above molecular weight in terms of terminal groups. It is also possible to calculate the number average molecular weight determined by GPC of the polymer (A) by converting it into a terminal group equivalent molecular weight.

The molecular weight distribution (Mw/Mn) of the polyoxyalkylene polymer (A) is not particularly limited, but is preferably narrow, preferably less than 2.0, more preferably 1.6 or less, and even more preferably 1.5 or less. , 1.4 or less is particularly preferable. The molecular weight distribution of the polyoxyalkylene polymer (A) can be determined from the number average molecular weight and weight average molecular weight obtained by GPC measurement.

Moreover, the main chain structure of the polyoxyalkylene polymer (A) of the present invention may be linear or branched.

<Synthesis method of polyoxyalkylene polymer (A)>
Next, a method for synthesizing the polyoxyalkylene polymer (A) will be explained.
The polyoxyalkylene polymer (A) having more than 1.0 reactive silicon groups on average at one terminal site has two reactive silicon groups at one terminal of the hydroxyl group-terminated polymer obtained by polymerization. After introducing the above carbon-carbon unsaturated bond, it is preferable to react with a reactive silicon group-containing compound that reacts with the carbon-carbon unsaturated bond. The above preferred synthesis method will be explained below.

(polymerization)
The polyoxyalkylene polymer (A) is preferably produced by polymerizing an epoxy compound with an initiator having a hydroxyl group using a multimetal cyanide complex catalyst such as a zinc hexacyanocobaltate glyme complex.

Examples of initiators with a hydroxyl group include ethylene glycol, propylene glycol, glycerin, pentaerythritol, low molecular weight polyoxypropylene glycol, polyoxypropylene triol, allyl alcohol, polypropylene monoallyl ether, polypropylene monoalkyl ether, etc. Examples include those having the above.

Examples of the epoxy compound include alkylene oxides such as ethylene oxide and propylene oxide, and glycidyl ethers such as methyl glycidyl ether and allyl glycidyl ether. Among these, propylene oxide is preferred.

(Introduction of carbon-carbon unsaturated bond)
A method for introducing two or more carbon-carbon unsaturated bonds into one terminal is to react a hydroxyl-terminated polymer with an alkali metal salt and then react with an epoxy compound having carbon-carbon unsaturated bonds. It is preferable to use a method in which a halogenated hydrocarbon compound having a carbon-carbon unsaturated bond is then reacted. By using this method, it becomes possible to efficiently and stably introduce reactive groups while controlling the molecular weight and molecular weight distribution of the polymer main chain depending on the polymerization conditions.

The alkali metal salt used in the present invention is preferably sodium hydroxide, sodium methoxide, sodium ethoxide, potassium hydroxide, potassium methoxide, or potassium ethoxide, and more preferably sodium methoxide or potassium methoxide. Sodium methoxide is particularly preferred in terms of availability.

The temperature at which the alkali metal salt is applied is preferably 50°C or higher and 150°C or lower, more preferably 110°C or higher and 140°C or lower. The time for allowing the alkali metal salt to act is preferably 10 minutes or more and 5 hours or less, more preferably 30 minutes or more and 3 hours or less.

As the epoxy compound having a carbon-carbon unsaturated bond used in the present invention, in particular, general formula (3):

A compound represented by (in the formula, R ¹ and R ² are the same as above) can be preferably used. Specifically, allyl glycidyl ether, methallyl glycidyl ether, glycidyl acrylate, glycidyl methacrylate, butadiene monoxide, and 1,4-cyclopentadiene monoepoxide are preferred from the viewpoint of reaction activity, and allyl glycidyl ether is particularly preferred.

The amount of the epoxy compound having a carbon-carbon unsaturated bond used in the present invention can be arbitrarily determined in consideration of the amount of carbon-carbon unsaturated bond introduced into the polymer and the reactivity. In particular, the molar ratio to the hydroxyl groups of the hydroxyl-terminated polymer is preferably 0.2 or more, more preferably 0.5 or more. Further, it is preferably 5.0 or less, more preferably 2.0 or less.

In the present invention, the reaction temperature when performing a ring-opening addition reaction of an epoxy compound having a carbon-carbon unsaturated bond to a polymer containing a hydroxyl group is preferably 60°C or higher and 150°C or lower, More preferably, the temperature is 110°C or higher and 140°C or lower.

Examples of the halogenated hydrocarbon compound having a carbon-carbon unsaturated bond used in the present invention include vinyl chloride, allyl chloride, methallyl chloride, vinyl bromide, allyl bromide, methallyl bromide, vinyl iodide, allyl iodide, and iodine. Examples include methallyl chloride, and it is more preferable to use allyl chloride and methallyl chloride for ease of handling.

The amount of the halogenated hydrocarbon compound having the above-mentioned carbon-carbon unsaturated bond added is not particularly limited, but the molar ratio to the hydroxyl group possessed by the hydroxyl group-terminated polymer is preferably 0.7 or more, and 1.0 or more. More preferred. Moreover, 5.0 or less is preferable, and 2.0 or less is more preferable.

The temperature at which the halogenated hydrocarbon compound having a carbon-carbon unsaturated bond is reacted is preferably 50°C or more and 150°C or less, more preferably 110°C or more and 140°C or less. The reaction time is preferably 10 minutes or more and 5 hours or less, more preferably 30 minutes or more and 3 hours or less.

(Introduction of reactive silicon group)
The method for introducing the reactive silicon group is not particularly limited, and any known method can be used. The introduction method is illustrated below.
(i) A method in which a hydrosilane compound is added to a polymer having a carbon-carbon unsaturated bond by a hydrosilylation reaction.
(ii) a polymer having a carbon-carbon unsaturated bond and a compound having both a group capable of reacting with the carbon-carbon unsaturated bond and a reactive silicon group (also called a silane coupling agent); How to react. Groups that can react with carbon-carbon unsaturated bonds to form bonds include, but are not limited to, mercapto groups.
(iii) A method of reacting a reactive group-containing polymer with a silane coupling agent. Combinations of reactive groups in the reactive group-containing polymer and the silane coupling agent include hydroxyl group and isocyanate group, hydroxyl group and epoxy group, amino group and isocyanate group, amino group and thioisocyanate group, amino group and epoxy group, and amino group. Examples include, but are not limited to, a group and an α,β-unsaturated carbonyl group (reaction by Michael addition), a carboxy group and an epoxy group, an unsaturated bond and a mercapto group, and the like.

Method (i) is preferable because the reaction is simple, the amount of introduced reactive silicon groups can be adjusted, and the physical properties of the resulting reactive silicon group-containing polyoxyalkylene polymer (A) are stable. Methods (ii) and (iii) are preferable because they have many reaction options and can easily increase the rate of introduction of reactive silicon groups.

Hydrosilane compounds that can be used in method (i) are not particularly limited, but include, for example, trimethoxysilane, triethoxysilane, tris(2-propenyloxy)silane, triacetoxysilane, dimethoxymethylsilane, diethoxymethylsilane, Dimethoxyethylsilane, (chloromethyl)dimethoxysilane, (chloromethyl)diethoxysilane, (methoxymethyl)dimethoxysilane, (methoxymethyl)diethoxysilane, (N,N-diethylaminomethyl)dimethoxysilane, (N,N- (diethylaminomethyl)diethoxysilane and the like.

The amount of the hydrosilane compound to be used is such that the molar ratio (number of moles of hydrosilane/number of moles of carbon-carbon unsaturated bonds) to the carbon-carbon unsaturated bonds in the precursor polymer is from 0.05 to 10. It is preferable from the viewpoint of performance, and 0.3 to 2 is more preferable from the viewpoint of economy.

Hydrosilylation reactions are accelerated by various catalysts. As the hydrosilylation catalyst, known catalysts such as various complexes of cobalt, nickel, iridium, platinum, palladium, rhodium, ruthenium, etc. may be used. For example, platinum supported on a carrier such as alumina, silica, or carbon black; chloroplatinic acid; chloroplatinic acid complexes consisting of chloroplatinic acid and alcohols, aldehydes, ketones, etc.; platinum-olefin complexes [e.g., Pt(CH ₂ = CH ₂ ) ₂ (PPh ₃ ), Pt(CH ₂ =CH ₂ ) ₂ Cl ₂ ]; platinum-vinylsiloxane complex [Pt{(vinyl)Me ₂ SiOSiMe ₂ (vinyl)}, Pt{Me(vinyl) SiO} ₄ ]; platinum-phosphine complex [Ph(PPh ₃ ) ₄ , Pt(PBu ₃ ) ₄ ]; platinum-phosphite complex [Pt{P(OPh) ₃ } ₄ ], and the like can be used. From the viewpoint of reaction efficiency, it is preferable to use a platinum catalyst such as chloroplatinic acid or a platinum vinyl siloxane complex.

Examples of the silane coupling agent that can be used in the method (ii) or (iii) above include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyldimethoxymethylsilane, and 3-mercaptopropyltrimethoxysilane, which react with unsaturated bonds. Mercaptosilanes such as ethoxysilane, mercaptomethyltriethoxysilane, mercaptomethyldimethoxymethylsilane; 3-isocyanatepropyltrimethoxysilane, 3-isocyanatepropyldimethoxymethylsilane, 3-isocyanatepropyltriethoxysilane, isocyanate that reacts with hydroxyl groups Isocyanate silanes such as methyltrimethoxysilane, isocyanatemethyltriethoxysilane, and isocyanatemethyldimethoxymethylsilane; 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyldimethoxy that reacts with hydroxyl, amino, or carboxy groups Epoxysilanes such as methylsilane, 3-glycidoxypropyltriethoxysilane, glycidoxymethyltrimethoxysilane, glycidoxymethyltriethoxysilane, and glycidoxymethyldimethoxymethylsilane; reacts with isocyanate groups or thioisocyanate groups 3-aminopropyltrimethoxysilane, 3-aminopropyldimethoxymethylsilane, 3-aminopropyltriethoxysilane, 3-(2-aminoethyl)propyltrimethoxysilane, 3-(2-aminoethyl)propyldimethoxymethyl Silane, 3-(2-aminoethyl)propyltriethoxysilane, 3-(N-ethylamino)-2-methylpropyltrimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N- Phenyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltrimethoxysilane, N-cyclohexylaminomethyltriethoxysilane, N-cyclohexylaminomethyldiethoxymethylsilane, N-phenylaminomethyltrimethoxysilane, Aminosilanes such as (2-aminoethyl)aminomethyltrimethoxysilane, N,N'-bis[3-(trimethoxysilyl)propyl]ethylenediamine, and bis(3-(trimethoxysilyl)propyl)amine; 3-hydroxy Examples include hydroxyalkylsilanes such as propyltrimethoxysilane and hydroxymethyltriethoxysilane.

The main chain of the polymer (A) includes an ester bond or general formula (4) within a range that does not impair the effects of the present invention.
-NR ⁶ -C(=O)- (4)
(wherein R ⁶ represents an organic group having 1 to 10 carbon atoms or a hydrogen atom) may contain an amide segment.

A cured product obtained from a curable composition containing a polymer (A) containing an ester bond or an amide segment may have high hardness and strength due to the action of hydrogen bonds and the like. However, the polymer (A) containing an amide segment or the like may be cleaved by heat or the like. Further, a curable composition containing a polymer (A) containing an amide segment or the like tends to have a high viscosity. Considering the above advantages and disadvantages, polyoxyalkylene containing an amide segment etc. may be used as the polymer (A), or a polyoxyalkylene containing no amide segment etc. may be used. .

The amide segment represented by the general formula (4) includes, for example, a reaction between an isocyanate group and a hydroxyl group, a reaction between an amino group and a carbonate, a reaction between an isocyanate group and an amino group, a reaction between an isocyanate group and a mercapto group. Examples include those formed by, etc. Moreover, those formed by the reaction of the above-mentioned amide segment containing an active hydrogen atom and an isocyanate group are also included in the amide segment represented by the general formula (4).

As a method for producing the polymer (A) containing an amide segment, for example, a polyoxyalkylene having an active hydrogen-containing group at the end is reacted with an excess polyisocyanate compound to produce a polymer having an isocyanate group at the end. After or simultaneously with the synthesis, general formula (5):
Z-R ⁷ -SiR ⁵ _c X _3-c (5)
(In the formula, R ⁵ , X and c are the same as above. R ⁷ is a divalent organic group, preferably a divalent hydrocarbon group having 1 to 20 carbon atoms. Z is a hydroxyl group, (carboxy group, mercapto group, primary amino group or secondary amino group)
A method can be mentioned in which the Z group of the silicon compound represented by is reacted with all or part of the isocyanate groups of the synthesized polymer.

There are no particular limitations on the silicon compound represented by the general formula (5), but examples include γ-aminopropyldimethoxymethylsilane, γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyl Silanes containing amino groups such as trimethoxysilane, N-(β-aminoethyl)-γ-aminopropyldimethoxymethylsilane, (N-phenyl)-γ-aminopropyltrimethoxysilane, N-ethylaminoisobutyltrimethoxysilane, etc. Silanes containing a hydroxyl group such as γ-hydroxypropyltrimethoxysilane; Silanes containing a mercapto group such as γ-mercaptopropyltrimethoxysilane and mercaptomethyltriethoxysilane; and the like. Also, JP-A No. 6-211879 (US Patent No. 5364955), JP-A No. 10-53637 (US Patent No. 5756751), JP-A No. 10-204144 (EP0831108), JP-A No. 2000-169544, and JP-A No. 2000-169545. As described in the issue, Michael addition reaction products of various α,β-unsaturated carbonyl compounds and primary amino group-containing silanes, or various (meth)acryloyl group-containing silanes and primary amino group-containing compounds. The Michael addition reaction product can also be used as the silicon compound represented by the general formula (5).

Further, as a method for producing the polymer (A) containing an amide segment, for example, polyoxyalkylene having an active hydrogen-containing group at the terminal is added to the general formula (6):
O=C=NR ⁷ -SiR ⁵ _c X _3-c (6)
(In the formula, R ⁷ , R ⁵ , X and c are the same as above.)
A method of reacting a reactive silicon group-containing isocyanate compound shown in the following can be mentioned.

The reactive silicon group-containing isocyanate compound represented by the general formula (6) is not particularly limited, but examples thereof include γ-trimethoxysilylpropylisocyanate, γ-triethoxysilylpropylisocyanate, γ-methyldimethoxysilylpropylisocyanate, γ-Methyldiethoxysilylpropylisocyanate, γ-(methoxymethyl)dimethoxysilylpropylisocyanate, trimethoxysilylmethylisocyanate, triethoxymethylsilylmethylisocyanate, dimethoxymethylsilylmethylisocyanate, diethoxymethylsilylmethylisocyanate, (methoxymethyl) Examples include dimethoxysilylmethylisocyanate.

When the polymer (A) contains an amide segment, the number (average value) of amide segments per molecule of the polymer (A) is preferably 1 to 10, more preferably 1.5 to 5, and 2 to 3. Particularly preferred. If this number is less than 1, the curability may not be sufficient, whereas if it is greater than 10, the polymer (A) may have a high viscosity and may be difficult to handle. In order to lower the viscosity of the curable composition and improve workability, the polymer (A) preferably does not contain an amide segment.

<<Reactive silicon group-containing (meth)acrylic acid ester polymer (B)>>
As a (meth)acrylic ester monomer constituting the main chain of a reactive silicon group-containing (meth)acrylic ester polymer (B) (also referred to as "(meth)acrylic ester polymer (B)") is not particularly limited, and various types can be used. Specifically, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate. , tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, n-heptyl (meth)acrylate, n-(meth)acrylate -Octyl, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, phenyl (meth)acrylate, tolyl (meth)acrylate, (meth)acrylate Benzyl acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, Stearyl (meth)acrylate , glycidyl (meth)acrylate, (3-trimethoxysilyl)propyl (meth)acrylate, (3-dimethoxymethylsilyl)propyl (meth)acrylate, (2-trimethoxysilyl)ethyl (meth)acrylate, (2-dimethoxymethylsilyl)ethyl (meth)acrylate, trimethoxysilylmethyl (meth)acrylate, (dimethoxymethylsilyl)methyl (meth)acrylate, ethylene oxide adduct of (meth)acrylic acid, (meth) Trifluoromethylmethyl acrylate, 2-trifluoromethylethyl (meth)acrylate, 2-perfluoroethylethyl (meth)acrylate, 2-perfluoroethyl-2-perfluorobutylethyl (meth)acrylate, ( Perfluoroethyl acrylate, (meth)trifluoromethyl acrylate, bis(trifluoromethyl)methyl (meth)acrylate, 2-trifluoromethyl-2-perfluoroethylethyl (meth)acrylate, (meth)acrylate ) (meth)acrylic acid monomers such as 2-perfluorohexylethyl acrylate, 2-perfluorodecylethyl (meth)acrylate, and 2-perfluorohexadecylethyl (meth)acrylate.

Examples of monomer units other than those mentioned above include acrylic acids such as acrylic acid and methacrylic acid; monomers containing amide groups such as N-methylol acrylamide and N-methylol methacrylamide; glycidyl acrylate and glycidyl methacrylate; , a monomer containing an epoxy group, a monomer containing a nitrogen-containing group such as diethylaminoethyl acrylate, diethylaminoethyl methacrylate, and the like.

As the (meth)acrylic acid ester polymer (B), a polymer obtained by copolymerizing a (meth)acrylic acid ester monomer and a vinyl monomer copolymerizable with the same can also be used. Vinyl monomers are not particularly limited, and include, for example, styrene monomers such as styrene, vinyltoluene, α-methylstyrene, chlorostyrene, styrenesulfonic acid and its salts; perfluoroethylene, perfluoropropylene, vinylidene fluoride, etc. fluorine-containing vinyl monomers; silicon-containing vinyl monomers such as vinyltrimethoxysilane and vinyltriethoxysilane; maleic anhydride, maleic acid, monoalkyl esters and dialkyl esters of maleic acid; fumaric acid, monoalkyl esters of fumaric acid and dialkyl esters; maleimide monomers such as maleimide, methylmaleimide, ethylmaleimide, propylmaleimide, butylmaleimide, hexylmaleimide, octylmaleimide, dodecylmaleimide, stearylmaleimide, phenylmaleimide, cyclohexylmaleimide; nitrile groups such as acrylonitrile and methacrylonitrile Containing vinyl monomers: Vinyl monomers containing amide groups such as acrylamide and methacrylamide; Vinyl ester monomers such as vinyl acetate, vinyl propionate, vinyl pivalate, vinyl benzoate, and vinyl cinnamate; Alkenyl monomers such as ethylene and propylene Monomers: Conjugated diene monomers such as butadiene and isoprene; examples include vinyl chloride, vinylidene chloride, allyl chloride, and allyl alcohol, and it is also possible to use a plurality of these as copolymerization components.

Among the (meth)acrylic acid ester polymers obtained from the above-mentioned monomers, a copolymer consisting of a (meth)acrylic acid ester monomer and optionally a styrene monomer is preferred because of its excellent physical properties. (Meth)acrylic ester polymers made of acid ester monomers and methacrylic ester monomers are more preferred, and acrylic ester polymers made of acrylic ester monomers are particularly preferred.

The (meth)acrylic acid ester polymer (B) has a reactive silicon group represented by the general formula (1) shown above. The reactive silicon group possessed by the (meth)acrylic acid ester polymer (B) may be the same as or different from the reactive silicon group possessed by the polyoxyalkylene polymer (A).
Specific examples of R ⁵ include a methyl group, an ethyl group, a chloromethyl group, a methoxymethyl group, and an N,N-diethylaminomethyl group, with preference given to a methyl group and an ethyl group.

Examples of X include hydroxyl group, hydrogen, halogen, alkoxy group, acyloxy group, ketoximate group, amino group, amide group, acid amide group, aminooxy group, mercapto group, and alkenyloxy group. Among these, alkoxy groups such as a methoxy group and an ethoxy group are more preferable, and a methoxy group and an ethoxy group are particularly preferable because they are mildly hydrolyzable and easy to handle.

Specifically, the reactive silicon group possessed by the (meth)acrylic acid ester polymer (B) includes a trimethoxysilyl group, a triethoxysilyl group, a tris(2-propenyloxy)silyl group, and a triacetoxysilyl group. , dimethoxymethylsilyl group, diethoxymethylsilyl group, dimethoxyethylsilyl group, (chloromethyl)dimethoxysilyl group, (chloromethyl)diethoxysilyl group, (methoxymethyl)dimethoxysilyl group, (methoxymethyl)diethoxysilyl group , (N,N-diethylaminomethyl)dimethoxysilyl group, (N,N-diethylaminomethyl)diethoxysilyl group, etc., but are not limited to these. Among these, methyldimethoxysilyl group, trimethoxysilyl group, triethoxysilyl group, (chloromethyl)dimethoxysilyl group, (methoxymethyl)dimethoxysilyl group, (methoxymethyl)diethoxysilyl group, (N,N- Diethylaminomethyl)dimethoxysilyl group is preferred because it exhibits high activity and can yield a cured product with good mechanical properties, and trimethoxysilyl group and triethoxysilyl group are more preferred because they yield a cured product with a high Young's modulus. , trimethoxysilyl group is more preferred.

The reactive silicon group equivalent of the (meth)acrylic acid ester polymer (B) is not particularly limited, but is preferably 0.1 mmol/g or more, more preferably 0.5 mmol/g or more, and 0.6 mmol/g or more. is even more preferable. The reactive silicon group equivalent is preferably 2.0 mmol/g or less, and more preferably 1.0 mmol/g or less from the viewpoint of suppressing a decrease in elongation of the cured product. Moreover, in order to obtain a highly rigid cured product with a high Young's modulus, it is particularly preferable that the reactive silicon group equivalent is 0.6 mmol/g or more and 1.0 mmol/g or less.

The method for introducing reactive silicon groups into the (meth)acrylic acid ester polymer is not particularly limited, and for example, the following method can be used.
(iv) A method of copolymerizing a compound having a polymerizable unsaturated group and a reactive silicon-containing group with the above monomer. Using this method, reactive silicon groups tend to be introduced randomly into the polymer backbone.
(v) A method of polymerizing a (meth)acrylic acid ester polymer using a mercaptosilane compound having a reactive silicon-containing group as a chain transfer agent. Using this method, reactive silicon groups can be introduced at the ends of the polymer.
(vi) A method of copolymerizing a compound having a polymerizable unsaturated group and a reactive functional group (V group), and then reacting the compound with a reactive silicon group and a functional group that reacts with the V group. Specifically, after copolymerizing 2-hydroxyethyl acrylate, an isocyanate silane having a reactive silicon-containing group is reacted, or after copolymerizing glycidyl acrylate, an aminosilane compound having a reactive silicon-containing group is reacted. An example is a method of reacting.
(vii) A method of modifying the terminal functional group of a (meth)acrylic acid ester polymer synthesized by a living radical polymerization method to introduce a reactive silicon group. (Meth)acrylic acid ester polymers obtained by living radical polymerization can easily introduce functional groups at the polymer ends, and by modifying this, reactive silicon groups can be introduced at the polymer ends.

Examples of silicon compounds that can be used to introduce reactive silicon groups into the (meth)acrylic acid ester polymer (B) using the above method include the following compounds. Compounds having a polymerizable unsaturated group and a reactive silicon-containing group used in method (iv) include 3-(dimethoxymethylsilyl)propyl (meth)acrylate and 3-(trimethoxysilyl) (meth)acrylate. Propyl, 3-(triethoxysilyl)propyl (meth)acrylate, (dimethoxymethylsilyl)methyl (meth)acrylate, (trimethoxysilyl)methyl (meth)acrylate, (triethoxysilyl) (meth)acrylate Methyl, 3-((methoxymethyl)dimethoxysilyl)propyl (meth)acrylate, and the like. From the viewpoint of availability, 3-(dimethoxymethylsilyl)propyl (meth)acrylate and 3-(trimethoxysilyl)propyl (meth)acrylate are particularly preferred.

Mercaptosilane compounds having reactive silicon-containing groups used in method (v) include 3-mercaptopropyldimethoxymethylsilane, 3-mercaptopropyltrimethoxysilane, (mercaptomethyl)dimethoxymethylsilane, (mercaptomethyl)trimethoxy Examples include silane.

Compounds having a reactive silicon group and a functional group reactive with a V group used in method (vi) include 3-isocyanatepropyldimethoxymethylsilane, 3-isocyanatepropyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, Isocyanate silane compounds such as isocyanatemethyldimethoxymethylsilane, isocyanatemethyltrimethoxysilane, isocyanatemethyltriethoxysilane; 3-glycidoxypropyldimethoxymethylsilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltri Epoxysilane compounds such as ethoxysilane, glycidoxymethyltrimethoxysilane, glycidoxymethyldimethoxymethylsilane, glycidoxymethyltriethoxysilane; 3-aminopropyldimethoxymethylsilane, 3-aminopropyltrimethoxysilane, 3- Aminopropyltriethoxysilane, aminomethyldimethoxymethylsilane, aminomethyltrimethoxysilane, aminomethyltriethoxysilane, N-cyclohexylaminomethyldimethoxymethylsilane, N-cyclohexylaminomethyltrimethoxysilane, N-cyclohexylaminomethyltriethoxysilane Examples include aminosilane compounds such as .

In method (vii), any modification reaction can be used; for example, a method using a compound having a functional group and a reactive silicon group that can react with the terminal reactive group obtained by polymerization, or a method using a compound having a reactive silicon group and a functional group that can react with the terminal reactive group obtained by polymerization; A method can be used in which a double bond is introduced at the end of a polymer using a compound having a reactive functional group and a double bond, and a reactive silicon group is introduced into this by hydrosilylation or the like.

Note that these methods may be used in any combination. For example, by combining method (vi) and method (v), it is possible to obtain a (meth)acrylic acid ester polymer (B) having reactive silicon groups at both the end of the molecular chain and/or the side chain.

The (meth)acrylic acid ester polymer (B) is highly likely to contain a polymer containing 40% by weight or more of an alkyl (meth)acrylate in which the alkyl has 1 to 3 carbon atoms based on the total monomers. This is preferable because it provides rigidity. The (meth)acrylic acid ester polymer (B) consists only of a polymer containing 40% by weight or more of an alkyl (meth)acrylate in which the alkyl has 1 to 3 carbon atoms based on the total monomers. However, together with the polymer, it also contains a polymer containing 40% by weight or more of alkyl (meth)acrylate in which the alkyl has 4 to 30 carbon atoms, and both are blended. This is preferable because rigidity, elongation, and strength are improved.

In addition, the (meth)acrylic acid ester polymer (B) contains at least 40% by weight of alkyl (meth)acrylate in which the alkyl has 1 to 3 carbon atoms, and the alkyl has 4 to 3 carbon atoms. It is also preferable to contain a polymer obtained by copolymerizing a monomer mixture containing 40% by weight or more of alkyl (meth)acrylate of No. 30 based on the total monomers, since rigidity, elongation, and strength are improved.

Next, the (meth)acrylic ester polymer (B) polymerized using a macromonomer, which is one of the preferred embodiments of the (meth)acrylic ester polymer (B) used in the present invention, will be explained. do.

The (meth)acrylic acid ester polymer (B) polymerized using a macromonomer is a monomer (b1) having a reactive silicon group and a polymerizable unsaturated group represented by the above-mentioned general formula (1). , and a macromonomer (b2) which is a (meth)acrylic acid ester polymer having a polymerizable unsaturated group as a constituent monomer. The polymer may further include a (meth)acrylic acid alkyl ester (b3) in which the alkyl has 1 to 3 carbon atoms as a constituent monomer. In addition, in this application, "(meth)acrylic" represents "acrylic and/or methacrylic."

(Monomer (b1) having a reactive silicon group and a polymerizable unsaturated group)
Examples of the monomer (b1) having a reactive silicon group and a polymerizable unsaturated group include 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 3-( Compounds having silicon groups reactive with (meth)acryloxy groups such as meta)acryloxypropyldimethoxymethylsilane, (meth)acryloxymethyltrimethoxysilane, and (meth)acryloxymethyldimethoxymethylsilane; vinyltrimethoxysilane, vinyl Examples include compounds having a vinyl group and a reactive silicon group, such as triethoxysilane. These compounds may be used alone or in combination of two or more.

The total content of the monomer (b1) having a reactive silicon group and a polymerizable unsaturated group is the total content of all the monomers constituting the (meth)acrylic acid ester polymer (B) polymerized using a macromonomer. It is preferably 0.1 to 50% by weight, more preferably 0.5 to 30% by weight, and even more preferably 1 to 20% by weight.

(Macromonomer (b2))
The macromonomer (b2) is a (meth)acrylic acid ester polymer having a polymerizable unsaturated group. The macromonomer (b2) is itself a polymer, but can be copolymerized with the monomer (b1) having a reactive silicon group and a polymerizable unsaturated group by the polymerizable unsaturated group, It is a monomer constituting the (meth)acrylic acid ester polymer (B).

The main chain skeleton of the macromonomer (b2) is a (meth)acrylic acid ester polymer. The monomer constituting the main chain skeleton of the macromonomer (b2) is not particularly limited, and various types can be used. Examples of (meth)acrylic monomers include (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, ( n-butyl meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, ( n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, (meth) Stearyl acrylate, phenyl (meth)acrylate, toluyl (meth)acrylate, benzyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, (meth)acrylic acid 2-hydroxyethyl, 2-hydroxypropyl (meth)acrylate, ethylene oxide adduct of (meth)acrylic acid, 2,2,2-trifluoroethyl (meth)acrylate, 3,3,3 (meth)acrylate -Trifluoropropyl, 3,3,4,4,4-pentafluorobutyl (meth)acrylate, 2-perfluoroethyl-2-perfluorobutylethyl (meth)acrylate, trifluoromethyl (meth)acrylate , perfluoroethyl (meth)acrylate, bis(trifluoromethyl)methyl (meth)acrylate, 2-trifluoromethyl-2-perfluoroethylethyl (meth)acrylate, 2-perfluoro(meth)acrylate Hexylethyl, 2-perfluorodecylethyl (meth)acrylate, 2-perfluorohexadecylethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, chloroethyl (meth)acrylate, tetrahydro (meth)acrylate Examples include furfuryl, glycidyl (meth)acrylate, and 2-aminoethyl (meth)acrylate.

Furthermore, other monomers that exhibit copolymerizability with the above (meth)acrylic monomer may also be used. Other monomers include, for example, styrene monomers such as styrene, vinyltoluene, α-methylstyrene, chlorostyrene, and styrene sulfonic acid; fluorine-containing vinyls such as perfluoroethylene, perfluoropropylene, and vinylidene fluoride. Monomer; maleic acid and its derivatives such as maleic acid, maleic anhydride, maleic acid monoalkyl ester, maleic acid dialkyl ester; fumaric acid and its derivatives such as fumaric acid, fumaric acid monoalkyl ester, fumaric acid dialkyl ester; Maleimide monomers such as maleimide, methylmaleimide, ethylmaleimide, propylmaleimide, butylmaleimide, hexylmaleimide, octylmaleimide, dodecylmaleimide, stearylmaleimide, phenylmaleimide, cyclohexylmaleimide; vinyl acetate, vinyl propionate, vinyl pivalate, Vinyl ester monomers such as vinyl benzoate and vinyl cinnamate; Olefin monomers such as ethylene and propylene; Conjugated diene monomers such as butadiene and isoprene; (meth)acrylamide; (meth)acrylonitrile; chloride Examples include vinyl monomers such as vinyl, vinylidene chloride, allyl chloride, allyl alcohol, ethyl vinyl ether, butyl vinyl ether. Only one type of other monomers may be used, or two or more types may be used in combination.

The macromonomer (b2) has a polymerizable unsaturated group, and thereby exhibits polymerizability. In the macromonomer (b2), the polymerizable unsaturated group may be introduced at either the molecular chain end or the side chain of the (meth)acrylic acid ester polymer, but from the viewpoint of adhesiveness, the polymerizable unsaturated group may be introduced at the molecular chain end. It is preferable that the

The polymerizable unsaturated group possessed by the macromonomer (b2) is not particularly limited as long as it is an unsaturated group that exhibits polymerizability in a general radical polymerization method, and includes, for example, an acryloyl group, a methacryloyl group, a vinyl group, and an allyl group. , methallyl group, etc. Acryloyl groups and methacryloyl groups are preferred because they exhibit good polymerizability.

The method for introducing the polymerizable unsaturated group into the macromonomer (b2) is not particularly limited, and for example, the methods shown in (viii) to (x) below can be used.
(viii) A method of copolymerizing a monomer having two types of polymerizable unsaturated groups with different reactivities (for example, allyl acrylate) together with a monomer having a (meth)acrylic structure.
(ix) After copolymerizing a compound having a polymerizable unsaturated group and a reactive functional group (Z group) (for example, acrylic acid, 2-hydroxyethyl acrylate) with a monomer having a (meth)acrylic structure, polymerization A method of reacting a compound having a sexually unsaturated group and a functional group that reacts with a Z group (for example, diethyl isocyanate (meth)acrylate).
(x) A method in which a monomer having a (meth)acrylic structure is polymerized by a living radical polymerization method, and then a polymerizable unsaturated group is introduced at the end of the molecular chain.

Note that these methods may be used in any combination.
Among these methods, method (x) is preferably used because it allows the introduction of a polymerizable unsaturated group at the end of the molecular chain. The "living radical polymerization method" uses a cobalt porphyrin complex as shown in, for example, Journal of the American Chemical Society (J.Am.Chem.Soc.), 1994, vol. 116, p. 7943. Those using nitroxide radicals as shown in Japanese Patent Publication No. 2003-500378, and those using organic halides and halogenated sulfonyl compounds as shown in JP-A No. 11-130931 as initiators. , atom transfer radical polymerization (ATRP method) using a transition metal complex as a catalyst, and the like. The atom transfer radical polymerization method is most preferable because it is easy to introduce a polymerizable unsaturated group at the terminal.

Alternatively, a method for obtaining a (meth)acrylic polymer using a metallocene catalyst and a thiol compound having at least one reactive silicon group in the molecule as shown in JP-A No. 2001-040037 is used. It is also possible.

The polymerizable unsaturated group contained in the macromonomer (b2) preferably has a structure represented by the following general formula (7).
CH ₂ =C(R ⁶ )-COO-Z (7)
(In the formula, R ⁶ represents hydrogen or a methyl group. Z represents the main chain skeleton of the macromonomer (b2).)

The number average molecular weight of the macromonomer (b2) is preferably 1,000 or more, more preferably 3,000 or more, even more preferably 5,000 or more, and preferably 50,000 or less, more preferably 30,000 or more. It is as follows. When the number average molecular weight of the macromonomer (b2) is small, the viscosity of the (meth)acrylic acid ester polymer (B) becomes low, but there is a tendency that good adhesiveness cannot be obtained. On the other hand, if the number average molecular weight of the macromonomer (b2) is too large, the viscosity tends to become too high and handling becomes difficult.

The molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) of the macromonomer (b2) is not particularly limited, but is preferably narrow, more preferably less than 2.0, even more preferably 1.6 or less, It is particularly preferably 1.5 or less, more particularly preferably 1.4 or less, even more particularly preferably 1.3 or less, and most preferably 1.2 or less.

The number average molecular weight (Mn) and weight average molecular weight (Mw) of the macromonomer (b2) are values measured by GPC (polystyrene equivalent), and detailed measurement methods will be described in Examples.

The (meth)acrylic acid ester polymer (B) is composed of the macromonomer (b2) and other monomers, but the main chain of the (meth)acrylic acid ester polymer (B) is the main chain. A polymer chain derived from the macromonomer (b2) and branched from the main chain is called a branch chain. The monomers constituting the main chain and branch chains are composed of the monomers mentioned above, and are not particularly limited. The Tg of the branch chain is preferably lower than the Tg of the main chain because good adhesion can be obtained.

The Tg of the main chain is preferably -60°C to 150°C, more preferably 0°C to 130°C, even more preferably 30°C to 100°C.

The Tg of the branch chain is preferably -100°C to 150°C, more preferably -90°C to 100°C, even more preferably -80°C to 50°C. Tg is obtained from the following Fox formula.
Fox's formula:
1/(Tg(K))=Σ(Mi/Tgi)
(In the formula, Mi represents the weight fraction of monomer i component constituting the polymer, and Tgi represents the glass transition temperature (K) of the homopolymer of monomer i.)

For the glass transition temperature of the homopolymer, the glass transition temperature (Tg) described in POLYMER HANDBOOK-FOURTH EDITION- (J. Brandrup et al.) is referred to. When Tg is calculated using the Fox formula, the monomer having a reactive silicon group is not included in the calculation.

The total content of the macromonomer (b2) is preferably 1 to 50% by weight, more preferably 5 to 40% by weight, based on the total monomers constituting the (meth)acrylic acid ester polymer (B), and 10% by weight. ˜30% by weight is even more preferred.

The macromonomer (b2) may be introduced at either the end of the molecular chain or the side chain of the (meth)acrylic acid ester polymer (B), but it should be introduced at the side chain from the viewpoint of adhesiveness. is preferred. The average number of macromonomers contained in one molecule of the (meth)acrylic acid ester polymer (B) is preferably 0.01 or more, more preferably 0.03 or more, and still more preferably 0.05 or more. , and is also preferably 2.0 or less, more preferably 1.5 or less, still more preferably 1.3 or less.

((meth)acrylic acid alkyl ester (b3))
The alkyl group constituting the (meth)acrylic acid alkyl ester (b3) has 1 to 3 carbon atoms. Specific examples of (b3) include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and isopropyl (meth)acrylate. These may be used alone or in combination of two or more.

From the viewpoint of achieving both flexibility and high rigidity, the total content of (meth)acrylic acid alkyl ester (b3) is determined from the viewpoint of achieving both flexibility and high rigidity. It is preferably 40% by weight or more, more preferably 45% by weight or more, and even more preferably 50% by weight or more based on the monomer. In order to ensure compatibility with the polyoxyalkylene polymer (A), the content is preferably 70% by weight or less, more preferably 65% by weight or less.

The (meth)acrylic acid ester polymer (B) polymerized using a macromonomer comprises at least a monomer (b1) having a reactive silicon group and a polymerizable unsaturated group, and a macromonomer (b2). Although the polymer is used as a monomer, it may contain (meth)acrylic acid alkyl ester (b3) in which the alkyl has 1 to 3 carbon atoms or other monomers as constituent monomers. . Examples of such monomers include (meth)acrylic monomers that do not fall under (b1) to (b3) and other monomers other than (meth)acrylic monomers. It is possible to use the various monomers exemplified for the macromonomer (b2) above.

The (meth)acrylic acid ester polymer (B) polymerized using a macromonomer is obtained by copolymerizing a monomer (b1) having a reactive silicon group and a polymerizable unsaturated group with another monomer. It is synthesized by This allows reactive silicon groups to be randomly introduced into the main chain of the polymer. However, in order to further introduce reactive silicon groups into the (meth)acrylic acid ester polymer (B), the above-mentioned methods can also be used in combination.

The monomer composition of the (meth)acrylic acid ester polymer (B) can be selected depending on the use and purpose. For uses that require strength, it is preferable to use one with a relatively high glass transition temperature (Tg). , preferably 0°C or more and 200°C or less, and more preferably 20°C or more and 100°C or less. Note that Tg is obtained from the above-mentioned Fox equation.

The number average molecular weight of the (meth)acrylic acid ester polymer (B) is not particularly limited, but it is preferably 500 to 50,000, more preferably 500 to 30,000, and more preferably 1,000 in polystyrene equivalent molecular weight by GPC measurement. ~10,000 is particularly preferred. Among these, the number average molecular weight of the (meth)acrylic acid ester polymer (B) is preferably 3000 or less, since it exhibits good adhesion even after a heat and humidity test.

The method of blending the (meth)acrylic acid ester polymer (B) and the polyoxyalkylene polymer (A) is disclosed in JP-A-59-122541, JP-A-63-112642, JP-A-6- This method has been proposed in JP-A No. 172631, Japanese Patent Laid-Open No. 11-116763, etc. In addition, a method of polymerizing a (meth)acrylic acid ester monomer in the presence of a polyoxypropylene polymer having a reactive silicon group can be used.

The weight ratio (A):(B) of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B) is preferably 95:5 to 50:50. Within this range, a cured product exhibiting flexibility and high shear adhesive strength can be obtained. Furthermore, in terms of achieving both high rigidity and flexibility, the ratio of (A):(B) is preferably 80:20 to 50:50, more preferably 70:30 to 50:50.

<<Epoxy resin (C)>>
As the epoxy resin (C), at least a bisphenol A type epoxy resin (C1) and an aminophenol type epoxy resin and/or a naphthalene type epoxy resin as the component (C2) are used in combination. In the present invention, by using bisphenol A type epoxy resin (C1) and component (C2) together, agent B shows high thixotropy before curing, and after curing, the modulus of elasticity at high temperatures decreases. A cured product with suppressed deterioration can be formed.

Bisphenol A type epoxy resin (C1) is a compound having a structure derived from bisphenol A and an epoxy group. Specifically, bisphenol A type epoxy resins produced by a condensation reaction of epichlorohydrin and bisphenol A, glycidyl ether type epoxy resins of tetrabromobisphenol A, glycidyl ether type epoxy resins of bisphenol A propylene oxide adducts, and the like can be mentioned.

Component (C2) may be either an aminophenol type epoxy resin or a naphthalene type epoxy resin, or a combination of both resins.
The aminophenol type epoxy resin (C2) is a compound having a structure derived from aminophenol and an epoxy group. Specific examples include triglycidyl p-aminophenol and m-aminophenol epoxy resins.
The naphthalene type epoxy resin (C2) is a compound having a naphthalene skeleton and an epoxy group. Specific examples include 1,6-bis(glycidyloxy)naphthalene and the like.

The ratio of the bisphenol A type epoxy resin (C1) and component (C2) used is not particularly limited, but from the viewpoint of improving thixotropy and suppressing a decrease in the elastic modulus of the cured product, a weight ratio of 10:90 to 90:10 is preferable. , 20:80 to 80:20 are more preferred, 30:70 to 70:30 are even more preferred, and 40:60 to 60:40 are particularly preferred.

The epoxy resin (C) may contain only the components (C1) and (C2), or may contain other epoxy resins in addition to these. The ratio of the total weight of components (C1) and (C2) to the total weight of epoxy resin (C) is not particularly limited, but is preferably 50 to 100% by weight, more preferably 70 to 100% by weight. It is preferably 90 to 100% by weight, and more preferably 90 to 100% by weight.

Epoxy resins other than components (C1) and (C2) are not particularly limited, but include, for example, flame-retardant epoxy resins such as epichlorohydrin-bisphenol F epoxy resin, novolak epoxy resin, hydrogenated bisphenol A epoxy resin, p - Oxybenzoic acid glycidyl ether ester type epoxy resin, diaminodiphenylmethane epoxy resin, urethane-modified epoxy resin, various alicyclic epoxy resins, N,N-diglycidylaniline, N,N-diglycidyl-o-toluidine, triglycidyl isocyanate Examples include glycidyl ethers of polyhydric alcohols such as nurate, polyalkylene glycol diglycidyl ether, and glycerin, hydantoin type epoxy resins, and epoxidized products of unsaturated polymers such as petroleum resins.

As the epoxy resin (C), an epoxy resin having at least two epoxy groups in one molecule is preferable because it has high reactivity during curing and the cured product can easily form a three-dimensional network.

The amount of epoxy resin (C) used is the total of polyoxyalkylene polymer (A) and (meth)acrylic acid ester polymer (B), and the weight ratio of epoxy resin (C) [(A+B):( C)] is preferably used in a ratio of 90:10 to 50:50. If the ratio of (A+B) is more than 90%, the strength will decrease, and if it is less than 50%, the flexibility will decrease and it will become too hard. Furthermore, the ratio of 80:20 to 60:40 is more preferable in terms of the balance between flexibility and strength.

Young's modulus is an index showing rigidity, and the Young's modulus of the cured product obtained by curing the curable composition of the present invention can be controlled by using the polyoxyalkylene polymer (A) and (meth) defined in the present invention. It is possible to arbitrarily adjust the weight ratio of the acrylic ester polymer (B) and the epoxy resin (C). For example, in order to prepare a cured product with a Young's modulus of less than 100 MPa measured at 23°C, (A):(B) should be 95:5 to 60:40, and (A+B):(C) should be 90:10. It is preferable to set the ratio to 60:40.

In addition, in order to prepare a cured product with a Young's modulus of 100 MPa or more when measured at 23°C, (A):(B) should be 80:20 to 50:50, and (A+B):(C) should be 70:30. It is preferable to set the ratio to 50:50.

<<Epoxy resin curing agent (D) having tertiary amine>>
As the epoxy resin curing agent (D) for curing the epoxy resin (C), it is preferable to use an epoxy resin curing agent having a tertiary amine. By using the epoxy resin curing agent (D) containing a tertiary amine, a cured product with high rigidity, high strength, and high elongation can be obtained.

As the epoxy resin curing agent (D) having a tertiary amine, any compound having a tertiary amine can be used. Specifically, for example, N,N,N',N'-tetramethyl-1,3-diaminopropane, N,N,N',N'-tetramethyl-1,6-diaminohexane, N,N -dimethylbenzylamine, N-methyl-N-(dimethylaminopropyl)aminoethanol, (dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol, tripropylamine, DBU, DBN, and these Examples include salts of tertiary amines, but are not limited thereto. Moreover, two or more types may be used in combination, and a known epoxy resin curing agent other than component (D) may be further added.

The epoxy resin curing agent (D) having a tertiary amine is preferably an aromatic amine, and more preferably has three or more amino groups. A specific example is 2,4,6-tris(dimethylaminomethyl)phenol.

The amount of the epoxy resin curing agent (D) used is preferably 0.1 to 60 parts by weight, more preferably 0.1 to 45 parts by weight, based on 100 parts by weight of the epoxy resin (C). More preferably, the amount is 0.5 to 30 parts by weight.

<<Fumed Silica (E)>>
Fumed silica (E) is blended into either or both of the A agent and the B agent. By blending fumed silica (E), the viscosity of Part A and/or Part B increases before curing, and also shows high thixotropy, and after curing, the elastic modulus decreases at high temperatures. It is possible to form a cured product in which the

The fumed silica (E) is not particularly limited, and commercially available products can be used. Since high thixotropy is obtained, the specific surface area measured by the BET method is preferably 50 m ² /g or more, more preferably 200 m ² /g or more, and even more preferably 300 m ² /g or more. Since a curable composition that can be handled at room temperature is obtained, the area is preferably 600 m ² /g or less, more preferably 450 m ² /g or less.

Both hydrophobic fumed silica and hydrophilic fumed silica can be used. Here, hydrophobic fumed silica is a product in which functional groups such as organosilicon compounds and silicone oil are chemically immobilized on the particle surface by utilizing the reaction between hydroxyl groups on the surface of fumed silica and organic compounds. Refers to a hydrophobized product. As the surface treatment agent, specifically, dimethyldichlorosilane, polydimethylsiloxane, hexamethyldisilazane, octyltrimethoxysilane, octyltrichlorosilane, etc. are used, but are not limited thereto. Hydrophilic fumed silica refers to fumed silica that has not been subjected to the above surface treatment, and the particles exhibit hydrophilicity.

Hydrophobic fumed silica and hydrophilic fumed silica may be used alone, but from the viewpoint of improving thixotropy and suppressing a decrease in the elastic modulus of the cured product, hydrophobic fumed silica and hydrophilic fumed silica may be used alone. It is preferable to use fumed silica together. In that case, the weight ratio of hydrophobic fumed silica to hydrophilic fumed silica is preferably 10:90 to 90:10, more preferably 20:80 to 80:20.

The amount of fumed silica (E) used is the total amount of polyoxyalkylene polymer (A) and (meth)acrylic acid ester polymer (B) when blending fumed silica (E) with agent A. Based on 100 parts by weight, the amount is preferably 1 part by weight or more, more preferably 3 parts by weight or more, even more preferably 5 parts by weight or more, and preferably 40 parts by weight or less. It is more preferably 30 parts by weight or less, and even more preferably 20 parts by weight or less. When fumed silica (E) is blended into agent B, it is preferably 1 part by weight or more, more preferably 2 parts by weight or more, and 3 parts by weight based on 100 parts by weight of the epoxy resin (C). It is more preferably the above amount, preferably 40 parts by weight or less, preferably 30 parts by weight or less, and even more preferably 20 parts by weight or less.

<<Silanol condensation catalyst (F)>>
In the present invention, for the purpose of promoting the reaction of condensing the reactive silicon groups of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B) and chain-extending or crosslinking the polymer, Preference is given to using a silanol condensation catalyst (F).

Examples of the silanol condensation catalyst (F) include organic tin compounds, carboxylic acid metal salts, amine compounds, carboxylic acids, alkoxy metals, and the like.

Specific examples of organotin compounds include dibutyltin dilaurate, dibutyltin dioctanoate, dibutyltin bis(butyl maleate), dibutyltin diacetate, dibutyltin oxide, dibutyltin bis(acetylacetonate), and dioctyltin bis(acetylacetonate). dioctyltin dilaurate, dioctyltin distearate, dioctyltin diacetate, dioctyltin oxide, reaction product of dibutyltin oxide and silicate compound, reaction product of dioctyltin oxide and silicate compound, dibutyltin oxide and phthalate ester Examples include reactants of

Specific examples of carboxylic acid metal salts include tin carboxylate, bismuth carboxylate, titanium carboxylate, zirconium carboxylate, iron carboxylate, and the like. As the carboxylic acid metal salt, the following carboxylic acids and various metals can be combined.

Specific examples of amine compounds include amines such as octylamine, 2-ethylhexylamine, laurylamine, and stearylamine; pyridine, 1,8-diazabicyclo[5,4,0]undecene-7 (DBU), 1, Nitrogen-containing heterocyclic compounds such as 5-diazabicyclo[4,3,0]nonene-5 (DBN); guanidines such as guanidine, phenylguanidine, and diphenylguanidine; butyl biguanide, 1-o-tolyl biguanide, and 1- Examples include biguanides such as phenylbiguanide; amino group-containing silane coupling agents; ketimine compounds.

Specific examples of carboxylic acids include acetic acid, propionic acid, butyric acid, 2-ethylhexanoic acid, lauric acid, stearic acid, oleic acid, linoleic acid, neodecanoic acid, versatic acid, and the like.

Specific examples of alkoxy metals include titanium compounds such as tetrabutyl titanate titanium tetrakis (acetylacetonate), diisopropoxy titanium bis (ethyl acetocetate), aluminum tris (acetylacetonate), diisopropoxy aluminum ethyl acetoacetate, etc. and zirconium compounds such as zirconium tetrakis (acetylacetonate).

When using the silanol condensation catalyst (F), the amount used is 0.00 parts by weight based on a total of 100 parts by weight of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B). The amount is preferably from 0.001 to 20 parts by weight, more preferably from 0.01 to 15 parts by weight, and particularly preferably from 0.01 to 10 parts by weight.

<<Water (G)>>
Water (G) may be added to the B agent of the composition of the present invention. By adding water, the curing of the polyoxyalkylene polymer (A) and (meth)acrylic acid ester polymer (B) is accelerated when the A and B agents are mixed.

The amount of water (G) added is preferably 0.1 to 10 parts by weight based on a total of 100 parts by weight of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B), More preferably 0.1 to 5 parts by weight, even more preferably 0.1 to 2 parts by weight. Moreover, the composition of the present invention may contain, in addition to the A agent and the B agent, a C agent containing water (G). In this case, the composition of the present invention will be of a three-component type.

<<Other additives>>
The composition of the present invention includes a polyoxyalkylene polymer (A), a (meth)acrylic acid ester polymer (B), an epoxy resin (C), an epoxy resin curing agent (D), and a fumed silica (E). ), silanol condensation catalyst (F), and water (G), as additives, fillers other than fumed silica, adhesive agents, anti-sagging agents, antioxidants, light stabilizers, ultraviolet absorbers, A tackifier resin and other resins may be added. Furthermore, various additives may be added to the curable composition of the present invention as necessary for the purpose of adjusting various physical properties of the curable composition or cured product. Examples of such additives include, for example, plasticizers, solvents, diluents, photocurable substances, oxygen curable substances, surface modifiers, silicates, curing modifiers, radical inhibitors, metal deactivators. agents, ozone deterioration inhibitors, phosphorous peroxide decomposers, lubricants, pigments, fungicides, flame retardants, foaming agents, etc.

<Filler>
The composition of the present invention may contain fillers other than fumed silica. Such fillers include ground calcium carbonate, colloidal calcium carbonate, magnesium carbonate, diatomaceous earth, clay, talc, titanium oxide, precipitated silica, crystalline silica, fused silica, wet silica, anhydrous silicic acid, and hydrated silica. Examples include acid, alumina, carbon black, ferric oxide, fine aluminum powder, zinc oxide, activated zinc white, PVC powder, PMMA powder, glass fiber, and filament.

The amount of filler other than fumed silica used is preferably 1 to 300 parts by weight based on the total of 100 parts by weight of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B). , particularly preferably 10 to 250 parts by weight.

An organic balloon or an inorganic balloon may be added for the purpose of making the composition lighter (lower specific gravity).

<Adhesive agent>
An adhesion-imparting agent can be added to the composition of the present invention.
As the adhesion imparting agent, a silane coupling agent or a reaction product of a silane coupling agent can be added.

Specific examples of silane coupling agents include γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β-aminoethyl-γ-aminopropyltrimethoxysilane, N-β-aminoethyl-γ- Amino group-containing silanes such as aminopropylmethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, (2-aminoethyl)aminomethyltrimethoxysilane; γ-isocyanatepropyltrimethoxysilane, γ-isocyanatepropyltrimethoxysilane Isocyanate group-containing silanes such as ethoxysilane, γ-isocyanatepropylmethyldimethoxysilane, α-isocyanatemethyltrimethoxysilane, α-isocyanatemethyldimethoxymethylsilane; γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, Examples include mercapto group-containing silanes such as γ-mercaptopropylmethyldimethoxysilane; epoxy group-containing silanes such as γ-glycidoxypropyltrimethoxysilane and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. .

The above-mentioned adhesion imparting agent may be used alone or in combination of two or more types. Moreover, reactants of various silane coupling agents can also be used.

The amount of the silane coupling agent used is preferably 0.1 to 20 parts by weight based on the total of 100 parts by weight of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B), Particularly preferred is 0.5 to 10 parts by weight.

<Anti-sagging agent>
If necessary, an anti-sagging agent may be added to the composition of the present invention in order to prevent sagging and improve workability. Anti-sagging agents include, but are not particularly limited to, polyamide waxes; hydrogenated castor oil derivatives; metal soaps such as calcium stearate, aluminum stearate, and barium stearate. These anti-sagging agents may be used alone or in combination of two or more.

The amount of the anti-sag agent used is preferably 0.1 to 20 parts by weight based on the total of 100 parts by weight of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B).

<Antioxidant>
Antioxidants (antiaging agents) can be used in the compositions of the present invention. Use of an antioxidant can improve the weather resistance of the cured product. Examples of antioxidants include hindered phenols, monophenols, bisphenols, and polyphenols. Specific examples of antioxidants are also described in JP-A-4-283259 and JP-A-9-194731.

The amount of the antioxidant to be used is preferably 0.1 to 10 parts by weight, particularly based on 100 parts by weight of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B). 0.2 to 5 parts by weight is preferred.

<Light stabilizer>
Light stabilizers can be used in the compositions of the invention. Use of a light stabilizer can prevent photooxidative deterioration of the cured product. Examples of light stabilizers include benzotriazole compounds, hindered amine compounds, and benzoate compounds, and hindered amine compounds are particularly preferred.

The amount of the light stabilizer to be used is preferably 0.1 to 10 parts by weight, particularly based on 100 parts by weight of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B). 0.2 to 5 parts by weight is preferred.

<Ultraviolet absorber>
Ultraviolet absorbers can be used in the compositions of the invention. Use of an ultraviolet absorber can improve the surface weather resistance of the cured product. Examples of ultraviolet absorbers include benzophenone, benzotriazole, salicylate, substituted tolyl, and metal chelate compounds, but benzotriazole compounds are particularly preferred, with commercial names such as Tinuvin P, Tinuvin 213, Tinuvin 234, Tinuvin 326, Examples include Tinuvin 327, Tinuvin 328, Tinuvin 329, and Tinuvin 571 (all manufactured by BASF).

The amount of the ultraviolet absorber to be used is preferably 0.1 to 10 parts by weight based on the total of 100 parts by weight of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B), particularly 0.2 to 5 parts by weight is preferred.

<Tackifying resin>
A tackifying resin can be added to the composition of the present invention for the purpose of improving adhesion or adhesion to a substrate, or for other purposes as necessary. There are no particular restrictions on the tackifying resin, and commonly used tackifying resins can be used.

Specific examples include terpene resins, aromatic modified terpene resins, hydrogenated terpene resins, terpene-phenolic resins, phenolic resins, modified phenolic resins, xylene-phenolic resins, cyclopentadiene-phenolic resins, coumaron-indene resins, and rosin-based resins. Resins, rosin ester resins, hydrogenated rosin ester resins, xylene resins, low molecular weight polystyrene resins, styrene copolymer resins, styrene block copolymers and their hydrogenated products, petroleum resins (e.g. C5 hydrocarbon resins, C9 Hydrocarbon resins, C5C9 hydrocarbon copolymer resins, etc.), hydrogenated petroleum resins, DCPD resins, and the like. These may be used alone or in combination of two or more.

The amount of the tackifying resin used is preferably 2 to 100 parts by weight, and 5 to 50 parts by weight based on the total of 100 parts by weight of the polyoxyalkylene polymer (A) and the (meth)acrylic acid ester polymer (B). More preferably, the amount is 5 to 30 parts by weight.

<<Preparation of curable composition>>
The curable composition of the present invention contains, as agent A, a polyoxyalkylene polymer (A), an acrylic ester polymer (B), an epoxy resin curing agent (D), and other additives; It is preferable to mix the epoxy resin (C) and other additives as the agent and prepare it as a two-component type in which the A agent and the B agent are mixed before use. Fumed silica (E) may be blended into either or both of the A agent and the B agent. In addition, in order to accelerate the curing reaction between the polyoxyalkylene polymer (A) and the acrylic ester polymer (B), a silanol condensation catalyst (F) and/or water (G) is added to the B agent. You may do so.

The curable composition of the present invention may be cured at room temperature or by heating. When joining dissimilar materials with an adhesive, especially when heat curing, thermal distortion due to the difference in linear expansion coefficients of the dissimilar materials may become a problem. Normally, when reaction-curing adhesives such as epoxy compositions and highly rigid urethane compositions are heated and cured, high adhesive strength is obtained, but flexibility is greatly reduced, resulting in thermal distortion when cooled. may occur. On the other hand, the curable composition of the present invention remains rubber-like with a Young's modulus of several MPa to several tens of MPa even when heat-cured to the extent that high adhesive strength is obtained, and the occurrence of thermal distortion can be suppressed. . Furthermore, since high rigidity can be developed through subsequent curing at room temperature, it is possible to produce a highly rigid adhesive that does not generate thermal distortion.

<<Surface treatment of adherend>>
The curable composition of the present invention can exhibit good adhesion to various adherends such as plastics, metals, and composite materials. In addition, when used as an adhesive for non-polar materials such as polypropylene or engineering plastics with rigid molecular chains such as polyphenylene sulfide, in order to improve adhesion to these adherends and obtain stable adhesive strength, The adherend can be surface-treated in advance by a known method. For example, surface treatment techniques such as sanding, flame treatment, corona discharge, arc discharge, plasma treatment, etc. can be used. Plasma treatment is preferred because it causes less damage to the adherend and provides stable adhesion. These surface treatments are also effective for removing the mold release agent used during molding and remaining on the surface of the adherend.

The curable composition of the present invention exhibits the desired physical properties by performing a long curing (curing) step after bonding the adherends. After obtaining a semi-cured product by subjecting the curable composition to a relatively short heating process, it is preferable to perform a long curing (curing) process. In this case, the structural adhesive of the present invention can be suitably used to bond adherends in a continuous line production system.

The conditions for the above-mentioned short-time heating step are not particularly limited, but include, for example, a temperature of 50 to 200°C and a time of 1 minute to 1 hour.

Furthermore, the conditions for the final curing (curing) step, which is carried out after the above-mentioned short-time heating step, in order for the curable composition of the present invention to exhibit the desired physical properties, are not particularly limited, but include, for example, temperature For example, the temperature may be 5 to 50°C, and the time may be 24 hours to 1 week.

<<Applications>>
The composition of the present invention is suitable for use as an adhesive composition, and can be used for sealing materials, adhesives, pressure-sensitive adhesives, waterproof materials, etc. for buildings, ships, automobiles, roads, etc. The cured product obtained by curing the curable composition of the present invention has flexibility despite being highly rigid, and among the above uses, it can be used as an adhesive, especially a structural adhesive. More preferred. In particular, when joining dissimilar materials such as aluminum-steel and aluminum-composite materials, thermal distortion occurs due to temperature changes because the linear expansion coefficients of the two materials are different. In such a case, an adhesive having high elongation is preferred in order to cope with thermal deformation, so the curable composition of the present invention can be suitably used for joining the dissimilar materials. When joining dissimilar materials, it is preferable to cover the joint with a sealer to prevent corrosion. As a sealer, it is possible to use a polymer having reactive silicon groups as shown in this application. The curable composition of the present invention is used in automobile parts such as vehicle panels, large vehicle parts such as trucks and buses, train vehicle parts, aircraft parts, marine parts, electrical parts, various mechanical parts, etc. Preferably, it is used as an adhesive.

The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to the Examples.

The number average molecular weight in the examples is the GPC molecular weight measured under the following conditions.
Liquid feeding system: Tosoh HLC-8120GPC
Column: Tosoh TSK-GEL H type Solvent: THF
Molecular weight: polystyrene equivalent Measurement temperature: 40°C

In the examples, the terminal group equivalent molecular weight was determined by determining the hydroxyl value by the measuring method of JIS K 1557, the iodine value by the measuring method of JIS K 0070, and calculating the structure of the organic polymer (branching degree determined by the polymerization initiator used). This is the molecular weight taken into consideration.

The average number of carbon-carbon unsaturated bonds introduced per terminal of the polymer (Q) shown in the examples was calculated using the following formula.
(Average number of introductions) = [unsaturated group concentration of polymer (Q) determined from iodine value (mol/g) - unsaturated group concentration of precursor polymer (P) determined from iodine value (mol/g)] /[hydroxyl group concentration (mol/g) of precursor polymer (P) determined from hydroxyl value].

The average number of silyl groups introduced per terminal of the polymer (A) shown in Examples was calculated by NMR measurement.

(Synthesis example 1)
Polyoxypropylene glycol with a number average molecular weight of about 2,000 is used as an initiator, and propylene oxide is polymerized with a zinc hexacyanocobaltate glyme complex catalyst. Polyoxypropylene (P-1) having a molecular weight of 17,700) and a molecular weight distribution Mw/Mn of 1.21 was obtained. 1.0 molar equivalent of sodium methoxide was added as a 28% methanol solution to the hydroxyl groups of the obtained hydroxyl group-terminated polyoxypropylene. After methanol was distilled off by vacuum devolatilization, 1.0 molar equivalent of allyl glycidyl ether was added to the hydroxyl group of the hydroxyl-terminated polyoxypropylene, and a reaction was carried out at 130° C. for 2 hours. Thereafter, 0.28 molar equivalent of a methanol solution of sodium methoxide was added to remove methanol, and 1.79 molar equivalent of allyl chloride was further added to convert the terminal hydroxyl group to an allyl group. After mixing and stirring 300 parts by weight of n-hexane and 300 parts by weight of water with respect to 100 parts by weight of the obtained unpurified allyl group-terminated polyoxypropylene, the water was removed by centrifugation, and the obtained hexane solution was obtained. Further, 300 parts by weight of water was mixed and stirred, water was removed by centrifugation again, and hexane was removed by devolatilization under reduced pressure. Through the above steps, polyoxypropylene (Q-1) having a terminal structure having two or more carbon-carbon unsaturated bonds was obtained. It was found that the polymer (Q-1) had an average of 2.0 carbon-carbon unsaturated bonds introduced into one terminal site.

A platinum divinyl disiloxane complex (3% by weight in terms of platinum in isopropanol solution) was added to 100 parts by weight of the obtained polyoxypropylene (Q-1) having an average of 2.0 carbon-carbon unsaturated bonds at one terminal site. 36 ppm was added, and 2.2 parts by weight of trimethoxysilane was slowly added dropwise while stirring. After reacting the mixed solution at 90°C for 2 hours, unreacted trimethoxysilane was distilled off under reduced pressure, resulting in an average of 1.6 trimethoxysilyl groups per molecule. A linear reactive silicon group-containing polyoxypropylene polymer (A-1) having an average of 3.2 silicon groups and a number average molecular weight of 28,500 was obtained.

(Synthesis example 2)
0.42 parts by weight of cuprous bromide and 20.0 parts by weight of butyl acrylate were added to the reactor in a deoxidized state, and the mixture was heated and stirred. 8.8 parts by weight of acetonitrile as a polymerization solvent and 1.90 parts by weight of ethyl 2-bromoadipate as an initiator were added and mixed, and the temperature of the mixture was adjusted to about 80°C. ) was added to start the polymerization reaction. Next, 80.0 parts by weight of butyl acrylate was successively added to advance the polymerization reaction. During the polymerization, triamine was added as appropriate to adjust the polymerization rate. The total amount of triamine used during polymerization was 0.15 parts by weight. When the monomer conversion rate (polymerization reaction rate) reached about 95% or more, volatile components were removed by devolatilization under reduced pressure to obtain a polymer concentrate.

Dilute the above concentrate with toluene, add a filter aid, adsorbent (Kyoward 700SEN: manufactured by Kyowa Chemical), and hydrotalcite (Kyoward 500SH: manufactured by Kyowa Chemical), and heat and stir to about 80 to 100°C. After that, solid components were removed by filtration. The filtrate was concentrated under reduced pressure to obtain a crudely purified polymer.

The crudely purified polymer, 1.98 parts by weight of potassium acrylate, 100 ppm of 4-hydroxy-TEMPO, and 100 parts by weight of dimethylacetamide as a solvent were added, and after reacting at 70°C for 3 hours, the solvent was distilled off under reduced pressure to obtain a polymer. A concentrate was obtained. The concentrate was diluted with toluene and the solid components were filtered off. The filtrate was concentrated under reduced pressure to obtain a macromonomer (b2-1) having an acryloyl group at one end, a number average molecular weight of 10,500 (GPC molecular weight), and a molecular weight distribution (Mw/Mn) of 1.18.

(Synthesis example 3)
48.0 parts by weight of isobutanol was placed in a four-necked flask equipped with a stirrer, and the temperature was raised to 105° C. under a nitrogen atmosphere. There, 60.0 parts by weight of methyl methacrylate, 10.0 parts by weight of stearyl methacrylate, 20 parts by weight of the macromonomer (b2-1) prepared in Synthesis Example 2, 10.0 parts by weight of 3-methacryloxypropyltrimethoxysilane, A mixed solution of 7.2 parts by weight of 3-mercaptopropyltrimethoxysilane and 2.5 parts by weight of 2,2'-azobis(2-methylbutyronitrile) dissolved in 22.7 parts by weight of isobutanol was heated for 5 hours. dripped. Polymerization was further carried out at 105°C for 2 hours, and an isobutanol solution (solid content 60 %) was obtained. The solid content of the solution has a macromonomer equivalent of 0.018 mmol/g and a reactive silicon group equivalent of 0.72 mmol/g.

(Example 1)
42 parts by weight of the reactive silicon group-containing polyoxypropylene polymer (A-1) obtained in Synthesis Example 1 and the (meth)acrylic acid ester polymer (B-1) obtained in Synthesis Example 3 were solidified. After mixing in such a manner that the amount of the components was 28 parts by weight, isobutanol was devolatilized by heating. To the resulting mixture were added 7 parts by weight of Ancamine K54 (2,4,6-tris(dimethylaminomethyl)phenol manufactured by Evonik) as an epoxy resin curing agent (D) and KBM-603 (N-(2-aminomethyl) as a silane coupling agent). 2 parts by weight of ethyl)-3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.), 4 parts by weight of TS720 (hydrophobic fumed silica manufactured by CABOT) as fumed silica (E), and AEROSIL 200 (hydrophilic Agent A was prepared by mixing 2 parts by weight of fumed silica (manufactured by Nippon Aerosil Co., Ltd.).

18 parts by weight of jER828 (bisphenol A epoxy resin manufactured by Mitsubishi Chemical Corporation) as bisphenol A epoxy resin (C1), jER630 (triglycidyl p-aminophenol manufactured by Mitsubishi Chemical Corporation) as aminophenol epoxy resin (C2) ) 18 parts by weight as fumed silica (E), 1.5 parts by weight of TS720 (hydrophobic fumed silica manufactured by CABOT), 4 parts by weight of Cylohobic 200 (hydrophobic colloidal silica manufactured by Fuji Silysia Chemical Co., Ltd.) as wet silica A B agent was prepared by mixing 0.3 parts by weight of Neostane U-810 (dioctyltin dilaurate manufactured by Nitto Kasei Co., Ltd.) as a silanol condensation catalyst (F) and 0.5 parts by weight of water.

(viscosity)
The viscosity of each of Agent A and Agent B was measured using a parallel disk plate with a diameter of 25 mm as a jig, setting the gap to 0.5 mm, and setting the rotation speed to 0.2 sec ^-1 or 10 sec ^-1 . . The device used was a rheometer (ARES-G2) manufactured by TA Instruments. The results obtained are shown in Table 1. Further, Table 1 shows the ratio of the viscosity at 0.2 sec ^-1 to the viscosity at 10 sec ^-1 as a viscosity ratio.

(Complex elastic modulus G*)
A sheet with a thickness of about 2 mm was prepared by mixing Agents A and B, and after heating at 80°C for 15 minutes, it was further cured for 7 days at 23°C and 50% RH, and then additionally cured at 80°C. I went there for one day. A 10 mm x 40 mm test piece was punched out from the obtained sheet, and a viscoelasticity test was conducted at a frequency of 1 Hz in the range of -80 to 100°C, and the complex modulus of elasticity G* was measured. The device used was a rheometer (ARES-G2) manufactured by TA Instruments. Table 1 shows the measurement results of the complex modulus at 23°C or 80°C. Further, Table 1 shows the numerical value of the complex elastic modulus at 80°C x 100 with respect to the complex elastic modulus at 23°C as a retention rate (%).

(Example 2 and Comparative Example 1-3)
A composition was prepared in the same manner as in Example 1 except that the formulation shown in Table 1 was changed, and the viscosity and complex modulus of elasticity were evaluated. The results are shown in Table 1.

In addition, in Table 1, the following compounds were used.
(1): 2,4,6-tris(dimethylaminomethyl)phenol (Evonik)
(2): N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd.)
(3): Hydrophobic fumed silica (CABOT)
(4): Hydrophilic fumed silica (Evonik)
(5): Bisphenol A epoxy resin (Mitsubishi Chemical Corporation)
(6): Triglycidyl p-aminophenol (Mitsubishi Chemical Corporation)
(7): 1,6-bis(glycidyloxy)naphthalene (DIC Corporation)
(8): Hydrophobic wet silica (Fuji Silysia Chemical Co., Ltd.)
(9): Dioctyltin dilaurate (Nitto Kasei Co., Ltd.)

As shown in Table 1, as the epoxy resin (C), an aminophenol type epoxy resin or a naphthalene type epoxy resin (C2) is blended together with a bisphenol A type epoxy resin (C1), and fumed silica (E) is added. The blended Examples 1 and 2 have a larger viscosity ratio than Comparative Example 1 which does not contain component (C2) or Comparative Example 3 which does not contain fumed silica (E). It can be seen that the elasticity is high, and the retention rate of the elastic modulus is large, and the elastic modulus decreases little from room temperature to high temperature.
In addition, Comparative Example 2 in which neither component (C2) nor fumed silica (E) was blended, and Comparative Example 1 in which fumed silica (E) was blended but component (C2) was not blended. In comparison, both comparative examples have the same retention rate of elastic modulus, so in a system that does not contain component (C2), even if fumed silica (E) is blended, the retention rate of elastic modulus is the same. I know it won't improve.
From the above, it can be seen that the combination of the aminophenol type epoxy resin or the naphthalene type epoxy resin (C2) and the fumed silica (E) can specifically suppress the decrease in the elastic modulus.

Claims (11)

A polyoxyalkylene polymer (A) having a reactive silicon group represented by general formula (1), a (meth)acrylic acid ester polymer (B) having a reactive silicon group represented by general formula (1), and , an epoxy resin curing agent (D) having a tertiary amine;
B agent containing epoxy resin (C),
A multi-component curable composition comprising:
The epoxy resin (C) contains a bisphenol A type epoxy resin (C1), and an aminophenol type epoxy resin and/or a naphthalene type epoxy resin (C2),
Either or both of the A agent and the B agent contain fumed silica (E),
A multi-component curable composition in which hydrophobic fumed silica and hydrophilic fumed silica are used together in a weight ratio of 20:80 to 80:20 as fumed silica (E) .
-SiR ⁵ _c X _3-c (1)
(In the formula, R ⁵ is a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. X represents a hydroxyl group or a hydrolyzable group. c represents 0 or 1.) The multi-component curable composition according to claim 1, wherein the reactive silicon group of the polyoxyalkylene polymer (A) is a trimethoxysilyl group. The multi-component curable composition according to claim 1 or 2, wherein the reactive silicon group of the (meth)acrylic acid ester polymer (B) is a trimethoxysilyl group. The terminal portion of the polyoxyalkylene polymer (A) has the general formula (2):

(In the formula, R ¹ and R ³ are each independently a divalent bonding group having 1 to 6 carbon atoms, and the atoms bonded to each carbon atom adjacent to R ¹ and R ³ are carbon, oxygen, nitrogen, R ² and R ⁴ are each independently hydrogen or a hydrocarbon group having 1 to 10 carbon atoms. n is an integer of 1 to 10. R ⁵ is a substituted or unsubstituted carbon The polycarbonate according to any one of claims 1 to 3, which is a hydrocarbon group of numbers 1 to 20. X is a hydroxyl group or a hydrolyzable group. c represents 0 or 1. Liquid type curable composition. The multi-component curable composition according to claim 4, wherein R ¹ is CH ₂ OCH ₂ and R ³ is CH ₂ . The multi-component curable composition according to claim 4 or 5, wherein R ² and R ⁴ are each a hydrogen atom. The (meth)acrylic acid ester polymer (B) is a monomer (b1) having a reactive silicon group and a polymerizable unsaturated group, and a (meth)acrylic acid ester polymer having a polymerizable unsaturated group. The multi-component curable composition according to any one of claims 1 to 6, which is a polymer comprising macromonomer (b2) as a constituent monomer. The multi-part curable composition according to any one of claims 1 to 7, wherein the aminophenol type epoxy resin is triglycidyl p-aminophenol. The multi-component curable composition according to any one of claims 1 to 7, wherein the naphthalene-type epoxy resin is 1,6-bis(glycidyloxy)naphthalene. A structural adhesive comprising the multi-component curable composition according to any one of claims 1 to 9. A cured product obtained by curing the multi-component curable composition according to any one of claims 1 to 9.