JP2023100363A - Curable composition and cured product thereof - Google Patents

Abstract

To provide a curable composition which contains an organic polymer having a reactive silicon group and can form a cured product having high strength.SOLUTION: There is provided a curable composition which comprises a (meth)acrylic ester-based copolymer (A) having a reactive silicon group and a polyester (B) having a reactive silicon group. A monomer component constituting the (meth)acrylic ester-based copolymer (A) contains a (meth)acrylic ester (a1), a polymer (a2) having more than one (meth)acryloyl group in the molecule and a chain transfer agent (a3) having a mercapto group. The monomer component further contains a monomer (a4) having a reactive silicon group and a polymerizable unsaturated group and/or the chain transfer agent (a3) having a mercapto group further contains a reactive silicon group.SELECTED DRAWING: None

Description

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

An organic polymer having a hydroxyl group or a hydrolyzable group on a silicon atom and having a silicon group capable of forming a siloxane bond by a hydrolysis/condensation reaction (hereinafter also referred to as a "reactive silicon group") can be used even at room temperature. Reacts with moisture, etc. It is known that a rubber-like cured product can be obtained by cross-linking such an organic polymer through a siloxane condensation reaction of reactive silicon groups.

Among these organic polymers, a polyoxyalkylene polymer having a reactive silicon group has a relatively low viscosity, so that it is excellent in workability when preparing or using a blended composition. In addition, since the resulting cured product has a good balance of performance such as mechanical properties, weather resistance, and dynamic durability, it is widely used for applications such as sealants, adhesives, and paints (see Patent Document 1).

In order to improve the weather resistance and adhesiveness of polyoxyalkylene polymers having reactive silicon groups, a combination of reactive silicon group-containing polyoxyalkylene polymers and reactive silicon group-containing (meth)acrylic acid ester polymers was used. A curable composition is known (see Patent Document 2). The curable compositions are used as highly weather-resistant sealants and industrial adhesives.

On the other hand, in Patent Document 3, for the purpose of eliminating the drawback that the curing speed of one-component moisture-curable adhesives using modified silicone or acrylic-modified silicone is slow, a curing agent having a high curing speed and excellent adhesiveness is disclosed. A reactive silicon synthesized by radically polymerizing an oligomer having a polyether skeleton and double bonds at both ends, a vinyl monomer such as a (meth)acrylic acid ester, and a chain transfer agent as a reactive resin. Group-containing graft copolymers are described.

JP-A-52-73998 JP-A-59-122541 Japanese Patent No. 5082851

A curable composition containing an organic polymer having a reactive silicon group is preferably cured to form a cured product with high strength.

An object of the present invention is to provide a curable composition containing an organic polymer having a reactive silicon group and capable of forming a cured product having high strength.

As a result of intensive studies to solve the above problems, the present inventors have found that a reactive silicon group-containing (meth)acrylic acid ester polymer is composed of a specific monomer and a chain transfer agent, and has a reactive The inventors have found that the above problems can be solved by using a silicon-containing polyester in combination, and have completed the present invention.

That is, the present invention provides a (meth)acrylic acid ester copolymer (A) having a reactive silicon group represented by the following general formula (1), and
Containing a polyester (B) having a reactive silicon group represented by the following general formula (1),
The monomer component constituting the (meth)acrylic acid ester copolymer (A) is
(meth) acrylic acid ester (a1),
A polymer (a2) having more than one (meth)acryloyl group in the molecule, and
containing a chain transfer agent (a3) having a mercapto group,
The monomer component further contains a monomer (a4) having a reactive silicon group and a polymerizable unsaturated group, and/or the chain transfer agent (a3) having a mercapto group is a reactive silicon It relates to a curable composition further comprising groups.
—SiR ¹ _3-a X _a (1)
(Wherein, R ¹ represents a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms; X represents a hydroxyl group or a hydrolyzable group; a is 2 or 3.)
Preferably, the polymer (a2) is a polyoxyalkylene polymer (a2″) having more than one (meth)acryloyl group in the molecule.
Preferably, the polymer (a2) is a (meth)acrylate polymer (a2') having more than one (meth)acryloyl group in the molecule.
Preferably, the molar ratio of polymer (a2)/chain transfer agent (a3) having a mercapto group is 0.05 or more.
Preferably, the polyester (B) has crystallinity.
The curable composition is preferably a hot-melt curable composition.
The present invention also relates to a cured product obtained by curing the curable composition.

ADVANTAGE OF THE INVENTION According to this invention, the curable composition which contains the organic polymer which has a reactive silicon group, and can form a hardened|cured material with high strength can be provided.
The curable composition according to the present invention can be suitably used as a hot-melt curable composition.

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

The curable composition according to this embodiment contains a (meth)acrylic acid ester copolymer (A) having a reactive silicon group and a polyester (B) having a reactive silicon group.

<<(Meth)acrylic acid ester copolymer (A) having a reactive silicon group>>
<Reactive silicon group>
The (meth)acrylic ester-based copolymer (A) has a reactive silicon group represented by the following general formula (1) at the molecular chain terminal and/or side chain (non-terminal site).
—SiR ¹ _3-a X _a (1)
(Wherein, R ¹ represents a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms; X represents a hydroxyl group or a hydrolyzable group; a represents 2 or 3.)

The number of carbon atoms in the hydrocarbon group of R ¹ is preferably 1-10, more preferably 1-5, even more preferably 1-3. Specific examples of R ¹ include methyl group, ethyl group, chloromethyl group, methoxymethyl group and N,N-diethylaminomethyl group. Preferred are methyl group, ethyl group, chloromethyl group and methoxymethyl group, and more preferred are methyl group and methoxymethyl group.

Examples of X include halogen, alkoxy group, acyloxy group, ketoximate group, amino group, amide group, acid amide group, aminooxy group, mercapto group and alkenyloxy group. Among these, an alkoxy group is more preferable, and a methoxy group and an ethoxy group are particularly preferable, since they are moderately hydrolyzable and easy to handle.

Specific examples of the reactive silicon group possessed by the (meth)acrylate copolymer (A) include 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, and the like. Among these are methyldimethoxysilyl, trimethoxysilyl, triethoxysilyl, (chloromethyl)dimethoxysilyl, (methoxymethyl)dimethoxysilyl, (methoxymethyl)diethoxysilyl, (N,N- Diethylaminomethyl)dimethoxysilyl group is preferred because it exhibits high activity and gives a cured product with good mechanical properties, and a trimethoxysilyl group and a triethoxysilyl group are more preferred because a cured product with a high Young's modulus is obtained. , and a trimethoxysilyl group are more preferred.

The reactive silicon group equivalent of the (meth)acrylate copolymer (A) is not particularly limited, but is preferably 0.2 mmol/g or more, more preferably 0.5 mmol/g or more, and 0.6 mmol/g. The above is more preferable. In addition, 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 and highly flexible cured product, the reactive silicon group equivalent is particularly preferably 0.5 mmol/g or more and 1.0 mmol/g or less.

<Monomer component>
The (meth)acrylic acid ester-based copolymer (A) includes at least a (meth)acrylic acid ester (a1), a polymer (a2) having more than one (meth)acryloyl group in the molecule, and a mercapto It is a polymer formed by copolymerizing a monomer component containing a chain transfer agent (a3) having a group. In the present application, "(meth)acryl" means "acryl and/or methacryl".

The (meth)acrylic ester-based copolymer (A) has reactive silicon groups by satisfying either one or both of the following two conditions.
Condition 1: The monomer component further contains a monomer (a4) having a reactive silicon group and a polymerizable unsaturated group.
Condition 2: The chain transfer agent (a3) having a mercapto group further has a reactive silicon group.
A curable composition containing a reactive silicon group-containing (meth)acrylic acid ester copolymer (A) that satisfies the above requirements can be cured to form a cured product having high strength. .

In order to obtain a cured product with high elongation, it is preferable that the number of reactive silicon groups introduced under condition 2 is larger than the number of reactive silicon groups introduced under condition 1. Specifically, the reactive silicon group equivalent introduced under Condition 1 is preferably 0.01 mmol/g or more, more preferably 0.03 mmol/g or more, and even more preferably 0.05 mmol/g or more. Further, the reactive silicon group equivalent introduced under Condition 1 is preferably 1.0 mmol/g or less, more preferably 0.5 mmol/g or less. On the other hand, the reactive silicon group equivalent introduced under Condition 2 is preferably 0.2 mmol/g or more, more preferably 0.3 mmol/g or more, and even more preferably 0.5 mmol/g or more. In addition, the reactive silicon group equivalent introduced under Condition 2 is preferably 1.5 mmol/g or less, more preferably 1.0 mmol/g or less.

In order to obtain a cured product having high strength, it is preferable to introduce a reactive silicon group under both conditions 1 and 2. Specifically, the reactive silicon group equivalent introduced under Condition 1 is preferably 0.1 mmol/g or more, more preferably 0.2 mmol/g or more, and even more preferably 0.3 mmol/g or more. Further, the reactive silicon group equivalent introduced under Condition 1 is preferably 1.8 mmol/g or less, more preferably 1.0 mmol/g or less. On the other hand, the reactive silicon group equivalent introduced under Condition 2 is preferably 0.1 mmol/g or more, more preferably 0.2 mmol/g or more, and even more preferably 0.3 mmol/g or more. In addition, the reactive silicon group equivalent introduced under Condition 2 is preferably 1.5 mmol/g or less, more preferably 1.0 mmol/g or less.

<(Meth) acrylic acid ester (a1)>
The (meth)acrylic acid ester (a1) is not particularly limited, and examples thereof include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, (meth) ) n-butyl acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) ) n-heptyl acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, (meth)acrylic stearyl acid, 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-perfluorohexyl (meth)acrylate Ethyl, 2-perfluorodecylethyl (meth)acrylate, 2-perfluorohexadecylethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, chloroethyl (meth)acrylate, tetrahydrofuran (meth)acrylate furyl, glycidyl (meth)acrylate, 2-aminoethyl (meth)acrylate and the like. Only one type may be used, or two or more types may be used in combination.
The (meth)acrylic acid ester (a1) is preferably a (meth)acrylic acid alkyl ester.

From the viewpoint of achieving both flexibility and high rigidity, the content of the (meth)acrylic acid ester (a1) is 30% relative to the total amount of the monomer components constituting the (meth)acrylic acid ester copolymer (A). It is preferably at least 40% by weight, even more preferably at least 45% by weight. The upper limit is preferably 80% by weight or less, more preferably 70% by weight or less, and even more preferably 65% by weight or less.

The (meth)acrylic acid ester (a1) preferably contains an alkyl (meth)acrylic acid ester in which the alkyl has 1 to 4 carbon atoms, since a cured product with high strength can be obtained. The (meth)acrylic acid alkyl ester in which the alkyl has 1 to 4 carbon atoms is contained in an amount of 30% by weight or more based on the total amount of the monomer components constituting the (meth)acrylic acid ester-based copolymer (A). 35% by weight or more is more preferable, and 40% by weight or more is even more preferable. The upper limit is preferably 70% by weight or less, more preferably 60% by weight or less, and even more preferably 55% by weight or less.

(Meth)acrylic acid ester (a1) can form a hard polymer chain to obtain a cured product with high strength. It preferably contains at least one monomer selected from the group consisting of dicyclopentanyl. In particular, among the total amount of the monomer components excluding the polymer (a2), at least one selected from the group consisting of methacrylate, isobornyl acrylate, dicyclopentenyl acrylate, and dicyclopentanyl acrylate The proportion of the seed monomer is preferably 60% by weight or more, more preferably 70% by weight or more.

<Polymer (a2) having more than one (meth)acryloyl group in the molecule>
Although the polymer (a2) is itself a polymer, it is one of the monomers constituting the (meth)acrylate copolymer (A). Since the polymer (a2) has a (meth)acryloyl group, it can be copolymerized with other monomers such as (meth)acrylic acid ester (a1). Moreover, since the polymer (a2) has more than one (meth)acryloyl group in one molecule, it can function as a so-called polyfunctional macromonomer. The main chain skeleton (second molecular chain described later) of the polymer (a2) is mainly composed of the (meth)acrylic acid ester (a1) in the (meth)acrylic acid ester-based copolymer (A) 2 It can form a structure that crosslinks the molecular chains (the first molecular chain described later). Hereinafter, the polymer (a2) is also referred to as polyfunctional macromonomer (a2).

The (meth)acryloyl group possessed by the polyfunctional macromonomer (a2) is preferably represented by the following formula (4).
_CH2 =C( ^R7 )-COO-Z (4)
(In the formula, R ⁷ represents hydrogen or a methyl group. Z represents the main chain skeleton of the polyfunctional macromonomer (a2).)

The polyfunctional macromonomer (a2) has more than one (meth)acryloyl group in one molecule on average. The average number of (meth)acryloyl groups per molecule of the polyfunctional macromonomer (a2) is preferably 1.1-5, more preferably 1.3-4, and 1.6-2. 5 is more preferred, and 1.8 to 2.0 is particularly preferred. As the (meth)acryloyl group, the polyfunctional macromonomer (a2) may have only an acryloyl group, may have only a methacryloyl group, or may have both an acryloyl group and a methacryloyl group. You may

The polyfunctional macromonomer (a2) can have a (meth)acryloyl group at either or both of the molecular chain terminal and the side chain of the polymer. From the standpoint of excellent mechanical properties, it is preferred to have it at the end of the molecular chain. In particular, it is particularly preferred that the polyfunctional macromonomer (a2) has a linear main chain skeleton and (meth)acryloyl groups at both ends of the molecular chain.

The main chain skeleton of the polyfunctional macromonomer (a2) is preferably a (meth)acrylate polymer or a polyoxyalkylene polymer. In the following, the polyfunctional macromonomer (a2) whose main chain skeleton is a (meth)acrylic acid ester polymer is denoted as (a2′), and the main chain skeleton is a polyoxyalkylene polymer. Macromonomer (a2) is denoted as (a2″).

First, the polyfunctional macromonomer (a2') will be described.
The monomer constituting the main chain skeleton of the polyfunctional macromonomer (a2') is not particularly limited, and various (meth)acrylic monomers 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, ( meth) n-butyl acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, ( meth)n-heptyl acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, (meth)acrylate 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)acrylic acid -trifluoropropyl, 3,3,4,4,4-pentafluorobutyl (meth)acrylate, 2-perfluoroethyl-2-perfluorobutylethyl (meth)acrylate, trifluoromethyl (meth)acrylate , (meth) perfluoroethyl acrylate, bis (trifluoromethyl) methyl (meth) acrylate, 2-trifluoromethyl-2-perfluoroethyl ethyl (meth) acrylate, 2-perfluoro (meth) acrylate Hexylethyl, 2-perfluorodecylethyl (meth)acrylate, 2-perfluorohexadecylethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, chloroethyl (meth)acrylate, tetrahydro(meth)acrylate furfuryl, glycidyl (meth)acrylate, 2-aminoethyl (meth)acrylate and the like.

Furthermore, other monomers that are copolymerizable with the above (meth)acrylic monomers may be used in combination. Other monomers include, for example, styrene-based monomers such as styrene, vinyltoluene, α-methylstyrene, chlorostyrene, and styrenesulfonic 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, and maleic acid dialkyl ester; Fumaric acid and its derivatives such as fumaric acid, fumaric acid monoalkyl ester, and fumaric acid dialkyl ester; Maleimide-based monomers such as maleimide, methylmaleimide, ethylmaleimide, propylmaleimide, butylmaleimide, hexylmaleimide, octylmaleimide, dodecylmaleimide, stearylmaleimide, phenylmaleimide, and 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; Vinyl monomers such as vinyl, vinylidene chloride, allyl chloride, allyl alcohol, ethyl vinyl ether and butyl vinyl ether are included. Other monomers may be used alone or in combination of two or more.

The main chain skeleton of the polyfunctional macromonomer (a2') is preferably composed of a soft polymer. Specifically, the monomer component forming the main chain skeleton of the polyfunctional macromonomer (a2′) is an acrylate ester (however, isobornyl acrylate, dicyclopentenyl acrylate, and dicyclopentaacrylate excluding nil) is preferably 60% by weight or more, more preferably 70% by weight or more. The upper limit may be 100% by weight.

Although the method for synthesizing the polyfunctional macromonomer (a2') is not particularly limited, for example, the method shown below can be used. The following methods may be used in combination.
(i) a copolymer obtained by copolymerizing a monomer having a reactive functional group (V group) (e.g., acrylic acid, 2-hydroxyethyl acrylate) with a (meth)acrylic monomer; with a compound having a functional group and (meth)acryloyl group that reacts with group V (eg, 2-isocyanatoethyl (meth)acrylate).
(ii) A method of polymerizing a (meth)acrylic monomer by a living radical polymerization method and then introducing (meth)acryloyl groups to the ends of the molecular chain (preferably both ends of the molecular chain).
Among these methods, it is preferable to use the method (ii) because it is possible to introduce a (meth)acryloyl group at the molecular chain terminal. The "living radical polymerization method" uses a cobalt porphyrin complex as shown, for example, in J. Am. Chem. Soc., 1994, 116, 7943. Those using nitroxide radicals as shown in JP-A-2003-500378, organic halides and sulfonyl halide compounds as shown in JP-A-11-130931 as initiators. , Atom Transfer Radical Polymerization (ATRP method) using a transition metal complex as a catalyst, and the like. Atom transfer radical polymerization is most preferred because it facilitates the introduction of (meth)acryloyl groups to the ends of the molecular chains.

Alternatively, a method of obtaining a (meth)acrylic polymer using a metallocene catalyst and a thiol compound having at least one reactive silicon group in the molecule as disclosed in JP-A-2001-040037 is used. is also possible.

Next, the polyfunctional macromonomer (a2″) will be described.
The polyoxyalkylene polymer that is the main chain skeleton of the polyfunctional macromonomer (a2″) is not particularly limited, and examples include polyoxyethylene, polyoxypropylene, polyoxybutylene, polyoxytetramethylene, and polyoxyethylene. -polyoxypropylene copolymer, polyoxypropylene-polyoxybutylene copolymer, etc. Among them, polyoxypropylene is preferred.

The main chain skeleton of the polyoxyalkylene polymer may be linear or branched, but is preferably linear.

Although the method for synthesizing the polyfunctional macromonomer (a2″) is not particularly limited, for example, a polyoxyalkylene polymer having more than one hydroxyl group in the molecule (preferably, a linear A method of preparing a polyoxyalkylene-based polymer) and introducing a (meth)acryloyl group using the hydroxyl group.

As an example of the method for synthesizing the polyfunctional macromonomer (a2″), a polyoxyalkylene polymer having a hydroxyl group is reacted with a compound having an isocyanate group and a (meth)acryloyl group to form a urethane bond. can introduce a (meth)acryloyl group.
Specific examples of the compound having an isocyanate group and a (meth)acryloyl group include isocyanatoethyl (meth)acrylate, isocyanatopropyl (meth)acrylate, isocyanatobutyl (meth)acrylate, isocyanatohexyl (meth)acrylate, and the like. be done.

As another example of the method for synthesizing the polyfunctional macromonomer (a2″), a polyoxyalkylene polymer having a hydroxyl group is reacted with a diisocyanate compound to introduce an isocyanate group into the polymer, and then the hydroxyl group and ( A (meth)acryloyl group can also be introduced by reacting a compound having a meth)acryloyl group.
Specific examples of the diisocyanate compound include tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-diphenylmethane diisocyanate, and the like.
Specific examples of the compound having a hydroxyl group and a (meth)acryloyl group include, for example, hydroxybutyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxyethyl (meth)acrylate, polyethylene glycol mono(meth)acryl acid esters, polypropylene glycol mono(meth)acrylic acid esters, and the like.

As yet another example of a method for synthesizing the polyfunctional macromonomer (a2″), a polyoxyalkylene polymer having a hydroxyl group is reacted with an acid anhydride to introduce a carboxyl group into the polymer, followed by epoxy A (meth)acryloyl group can also be introduced by reacting the group with a compound having a (meth)acryloyl group.
Specific examples of the acid anhydride include succinic anhydride, maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, and methyl anhydride. Himic acid, trimellitic anhydride, methyl nadic anhydride, dodecyl succinic anhydride and the like.
Specific examples of the compound having an epoxy group and a (meth)acryloyl group include glycidyl (meth)acrylate.

Still another example of the method for synthesizing the polyfunctional macromonomer (a2″) is a method of dehydration condensation of methacrylic acid and acrylic acid on a polyoxyalkylene polymer having a hydroxyl group. In order to carry out under mild conditions, methacrylic acid chloride, methacrylic acid bromide, methacrylic acid iodide, acrylic acid chloride, acrylic acid bromide, acrylic acid iodide, etc. are reacted with a polyoxyalkylene polymer having a hydroxyl group. There is a way.

The number average molecular weight of the polyfunctional macromonomer (a2) is not particularly limited, but is preferably 500 or more from the viewpoint of achieving both the mechanical properties and adhesiveness exhibited by the cured product and the ease of handling of (a2). ,000 or more is more preferable, and 2,000 or more is even more preferable. Also, it is preferably 100,000 or less, more preferably 50,000 or less, even more preferably 40,000 or less, and particularly preferably 30,000 or less.

The weight average molecular weight of the polyfunctional macromonomer (a2) is not particularly limited, but is preferably 500 or more from the viewpoint of achieving both the mechanical properties and adhesive properties exhibited by the cured product and the ease of handling of (a2). ,000 or more is preferable, and 2,500 or more is more preferable. Also, it is preferably 130,000 or less, more preferably 65,000 or less, even more preferably 60,000 or less, and even more preferably 30,000 or less.

The molecular weight distribution (weight average molecular weight (Mw)/number average molecular weight (Mn)) of the polyfunctional macromonomer (a2) is not particularly limited, but is preferably narrow, specifically less than 2.0. 6 or less is more preferable, 1.5 or less is more preferable, 1.4 or less is even more preferable, 1.3 or less is particularly preferable, and 1.2 or less is most preferable.

The number average molecular weight (Mn) and weight average molecular weight (Mw) of the polyfunctional macromonomer (a2) are values measured by GPC (converted to polystyrene), and detailed measurement methods are described in Examples.

The (meth)acrylic acid ester-based copolymer (A) has a molecular chain mainly composed of the (meth)acrylic acid ester (a1) and a molecule derived from the main chain skeleton of the polyfunctional macromonomer (a2). have chains. Since the polyfunctional macromonomer (a2) has more than one (meth)acryloyl group in one molecule, which is a polymerizable group, the (meth)acrylic acid ester copolymer (A) is a polyfunctional macro It may have a structure in which more than one molecular chain mainly composed of the (meth)acrylic acid ester (a1) is bonded to one molecular chain derived from the main chain skeleton of the monomer (a2). The molecular chain derived from the main chain skeleton of the polyfunctional macromonomer (a2) is introduced into either the terminal or the side chain (non-terminal portion) of the molecular chain mainly composed of the (meth)acrylic acid ester (a1). However, from the viewpoint of adhesiveness, it is preferably introduced into the side chain.

In particular, when the polyfunctional macromonomer (a2) has a (meth)acryloyl group at each of both ends of the main chain skeleton, each of both ends of the molecular chain derived from the main chain skeleton of the polyfunctional macromonomer (a2) , an H-type structure can be formed in which molecular chains composed mainly of (meth)acrylic acid ester (a1) are bonded. Here, the molecular chain derived from the main chain skeleton of the polyfunctional macromonomer (a2) corresponds to the horizontal bar of H, and the molecular chain mainly composed of the (meth)acrylic acid ester (a1) Corresponds to the two vertical bars included. The H-shaped structure will be described later.

The content of the polyfunctional macromonomer (a2) is preferably 1% by weight or more and 70% by weight or less with respect to the total amount of the monomer components constituting the (meth)acrylate copolymer (A). , 5 wt % or more and 60 wt % or less, more preferably 10 wt % or more and 50 wt % or less, and particularly preferably 15 wt % or more and 45 wt % or less. Above all, when obtaining a cured product with a high Young's modulus, the content of the polyfunctional macromonomer (a2) is preferably less than 35% by weight. On the other hand, when obtaining a cured product with a low Young's modulus, the content of the polyfunctional macromonomer (a2) is preferably 35% by weight or more.

In addition, the content of the polyfunctional macromonomer (a2) is 0.05 mol% or more and 6.0 mol% or less in the monomer components constituting the (meth)acrylate copolymer (A). It preferably accounts for 0.1 mol % or more and 2.3 mol % or less, and even more preferably 0.2 mol % or more and 1.5 mol % or less. Within the above range, the effect of using the polyfunctional macromonomer (a2) can be achieved while suppressing gelation during the synthesis of the (meth)acrylate copolymer (A).

The average number of polyfunctional macromonomers (a2) per molecule of (meth)acrylic acid ester copolymer (A) is 0.05 or more and 2.0 or less from the viewpoint of the strength of the resulting cured product. is preferred. The lower limit is more preferably 0.07 or more, and even more preferably 0.08 or more. The upper limit is more preferably 1.5 or less, even more preferably 1.0 or less. The average number can be calculated by the following formula.
Formula: Number average molecular weight (g / mol) of (meth) acrylic ester copolymer (A) / ((meth) acrylic ester copolymer (A) weight (g) / (polyfunctional macro Number of moles of monomer (a2)))

<Chain transfer agent (a3) having a mercapto group>
A polyfunctional macromonomer (a2) is used by including a chain transfer agent (a3) having a mercapto group in the monomer component constituting the (meth)acrylate copolymer (A). Nevertheless, the molecular weight distribution of the (meth)acrylic acid ester copolymer (A) is relatively narrowed, and gelation is suppressed when synthesizing the (meth)acrylic acid ester copolymer (A). can do. In addition, it becomes possible to preferentially synthesize a polymer molecule in which one molecule of the polyfunctional macromonomer (a2) is introduced into one molecule of the (meth)acrylate copolymer (A).

The chain transfer agent (a3) having a mercapto group may not have a reactive silicon group, but preferably has a reactive silicon group. The reactive silicon group is a reactive silicon group represented by formula (1) described above. When the chain transfer agent (a3) having a mercapto group has a reactive silicon group, a reactive silicon group can be introduced at the end of the molecular chain mainly composed of the (meth)acrylic acid ester (a1). .

Although the chain transfer agent (a3) having a mercapto group is not particularly limited, examples thereof include 3-mercaptopropyldimethoxymethylsilane, 3-mercaptopropyltrimethoxysilane, (mercaptomethyl)dimethoxymethylsilane, (mercaptomethyl)trimethoxysilane. , n-dodecylmercaptan, tert-dodecylmercaptan, laurylmercaptan and the like.

The content of the chain transfer agent (a3) having a mercapto group is 1% by weight or more and 15% by weight or less with respect to the total amount of the monomer components constituting the (meth)acrylate copolymer (A). is preferred, more preferably 2 wt % or more and 10 wt % or less, and more preferably 3 wt % or more and 8 wt % or less.

In addition, the content of the chain transfer agent (a3) having a mercapto group accounts for 0.1 mol% or more and 20 mol% or less of the monomer components constituting the (meth)acrylate copolymer (A). preferably 0.4 mol% or more and 15 mol% or less, more preferably 0.5 mol% or more and 10 mol% or less, and 0.6 mol% or more and 8 mol% or less is particularly preferred. Within the above range, the effect of using the chain transfer agent (a3) having a mercapto group can be achieved.

The content of the polyfunctional macromonomer (a2) and the content of the chain transfer agent (a3) having a mercapto group improve the strength of the resulting cured product, so that the polyfunctional macromonomer (a2)/mercapto group The molar ratio of the chain transfer agent (a3) to have is preferably 0.03 or more, more preferably 0.05 or more, still more preferably 0.09 or more, and particularly preferably 0.1 or more. Although the upper limit of the molar ratio is not particularly limited, it is preferably 1 or less, more preferably 0.5 or less, and even more preferably 0.3 or less.

The (meth)acrylic acid ester copolymer (A) may have a substituent derived from the chain transfer agent (a3) having a mercapto group (structure represented by -SR ⁸ described later). Therefore, it may contain sulfur atoms. The sulfur atom concentration in the (meth)acrylate copolymer (A) is preferably 700 ppm or more and 20,000 ppm or less, more preferably 1,000 ppm or more and 15,000 ppm or less.

A method for measuring the sulfur atom concentration is not particularly limited. It can be measured by known elemental analysis methods such as organic elemental analysis and fluorescent X-ray analysis. Further, the sulfur atom concentration is calculated from the total amount of the monomer components used in the production of the (meth)acrylate copolymer (A) and the amount (a3) of the chain transfer agent having a mercapto group. It may be a theoretical value.

<Monomer (a4) having a reactive silicon group and a polymerizable unsaturated group>
The monomer (a4) having a reactive silicon group and a polymerizable unsaturated group is an arbitrary monomer and may not be used, but is preferably used. The reactive silicon group possessed by the monomer (a4) is the reactive silicon group represented by formula (1) described above. By using the monomer (a4), a reactive silicon group can be introduced into the side chain (non-terminal portion) of the molecular chain mainly composed of the (meth)acrylic acid ester (a1).

Examples of the monomer (a4) having a reactive silicon group and a polymerizable unsaturated group include 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 3-( Compounds having a (meth)acryloxy group and a reactive silicon group, such as meth)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 use only 1 type and may use 2 or more types together.

When using the monomer (a4), the content of the monomer (a4) is 0.1 weight with respect to the total amount of the monomer components constituting the (meth)acrylic acid ester copolymer (A) % or more and 50 wt % or less, more preferably 0.5 wt % or more and 30 wt % or less, even more preferably 1 wt % or more and 20 wt % or less, and particularly preferably 2 wt % or more and 15 wt % or less. Moreover, the content of the monomer (a4) is preferably 10% by weight or less from the viewpoint of improving the thixotropy of the curable composition and obtaining a cured product with high elongation.

<Other monomer (b5)>
The monomer component constituting the (meth)acrylic acid ester-based copolymer (A) contains another monomer (b5) that does not correspond to any of (a1) to (a4) detailed above. It may contain, or may not contain.
Other monomers (b5) include (meth)acrylic esters (a1) and monomers (a4) having a reactive silicon group and a polymerizable unsaturated group (meth)acrylic monomers and monomers other than the (meth)acrylic monomer. Specifically, other monomers described above for multifunctional macromonomer (a2') can be used.

<Molecular weight of (meth)acrylate copolymer (A)>
The number average molecular weight of the (meth)acrylic acid ester copolymer (A) is not particularly limited, but is preferably 500 or more and 50,000 or less, preferably 500 or more and 30,000 or less, in terms of polystyrene equivalent molecular weight by GPC measurement. More preferably, 1,000 or more and 10,000 or less are particularly preferable. Among them, the number average molecular weight is preferably 7,000 or less because a (meth)acrylate copolymer (A) having a low viscosity can be obtained. In addition, the number average molecular weight is preferably 3,500 or less because good adhesiveness can be exhibited with low viscosity.

The weight average molecular weight of the (meth)acrylic acid ester copolymer (A) is not particularly limited, but the polystyrene equivalent molecular weight by GPC measurement is preferably 500 or more and 80,000 or less, and 3,000 or more and 70,000. The following are more preferable, and 5,000 or more and 65,000 or less are particularly preferable. Among them, the weight-average molecular weight is preferably 20,000 or less because a cured product having a low viscosity and a high strength can be obtained.

Regarding the weight average molecular weight of the (meth)acrylate copolymer (A) and the weight average molecular weight of the polyfunctional macromonomer (a2), the value calculated by the following formula is 1.1 or more. is preferred.
Formula: (weight average molecular weight of copolymer (A))/(weight average molecular weight of polyfunctional macromonomer (a2))
The fact that the value calculated by the above formula is 1.1 or more means that the average number of introduction of the polyfunctional macromonomer (a2) in one molecule of the (meth)acrylic acid ester copolymer (A) is large. It means that the strength of the resulting cured product can be further improved.
From the viewpoint of the strength of the cured product, the value calculated by the above formula is preferably 1.1 or more, more preferably 1.2 or more, and even more preferably 1.3 or more. Although the upper limit is not particularly limited, it is preferably 10 or less, more preferably 5 or less.

The molecular weight distribution of the (meth)acrylic acid ester copolymer (A) is not particularly limited, but from the viewpoint of making the (meth)acrylic acid ester copolymer (A) low in viscosity, it is 3.0 to 11.0. The following is preferable, 3.2 to 10.0 is more preferable, and 3.4 to 8.0 is even more preferable. The molecular weight distribution of the (meth)acrylate copolymer (A) can be determined from the number average molecular weight and weight average molecular weight obtained by GPC measurement.

<Structure of (meth)acrylate copolymer (A)>
According to a preferred embodiment, the (meth)acrylate copolymer (A) may contain a triblock copolymer. The triblock copolymer comprises a structure in which two first molecular chains are linked via one second molecular chain. The first molecular chain is mainly composed of a molecular chain obtained by polymerizing the (meth)acrylic acid ester (a1), and the second molecular chain is composed of the main chain skeleton of the polyfunctional macromonomer (a2). .

The first molecular chain is a molecular chain formed by copolymerization of (a1), (meth)acryloyl groups in (a2), (a3), optional (a4), and optional other monomers. . A reactive silicon group is attached to this first molecular chain. When the chain transfer agent (a3) having a mercapto group has a reactive silicon group, a reactive silicon group is bonded to the end of the first molecular chain, and a monomer having a reactive silicon group and a polymerizable unsaturated group ( When a4) is used, a reactive silicon group is attached to the non-terminal portion of the first molecular chain.
On the other hand, the second molecular chain corresponds to the main chain skeleton of the (meth)acrylate polymer or polyoxyalkylene polymer in the polyfunctional macromonomer (a2).

The bonding method of two first molecular chains and one second molecular chain is different from that of ordinary ABA-type triblock copolymers, and both ends of the second molecular chain are respectively non-terminal sites of the first molecular chain. is a form that is bound to That is, the triblock copolymer comprises an H-type structure, where two vertical bars in H correspond to two first molecular chains and one horizontal bar in H corresponds to one second molecular chain. It corresponds to a molecular chain.

However, the (meth)acrylic acid ester-based copolymer (A) is not limited to a triblock copolymer with an H-type structure, and in addition to a triblock copolymer with an H-type structure, It may contain a block copolymer having Block copolymers having such other structures include, for example, block copolymers having a structure in which three first molecular chains are bonded via two second molecular chains.

The first molecular chain and the second molecular chain have an ester bond derived from the (meth)acryloyl group in the polyfunctional macromonomer (a2) (that is, an ester bond corresponding to the ester bond in the formula (4)). are connected through

When the first molecular chain is composed of a hard polymer and the second molecular chain is composed of a soft polymer, it is preferable because a cured product having high strength and high elongation can be obtained. Here, a hard polymer refers to a polymer with a high glass transition temperature. A soft polymer refers to a polymer with a low glass transition temperature.

When the first molecular chain is composed of a rigid polymer, the monomer components constituting the first molecular chain (that is, the monomer components excluding the polyfunctional macromonomer (a2)) are methacrylic acid esters, It preferably contains at least one monomer selected from the group consisting of isobornyl acrylate, dicyclopentenyl acrylate, and dicyclopentanyl acrylate. The ratio of the monomers to the total amount of monomer components constituting the first molecular chain is preferably 60% by weight or more, more preferably 70% by weight or more. The upper limit may be 100% by weight.

In addition, when the second molecular chain is composed of a soft polymer, the second molecular chain may be the main chain skeleton of a polyoxyalkylene-based polymer, or a (meth)acrylic acid ester-based polymer. There may be. However, in the latter case, the monomer component constituting the second molecular chain (the monomer component forming the main chain skeleton of (a2′)) is an acrylate ester (however, isobornyl acrylate, dicycloacrylate excluding pentenyl and dicyclopentanyl acrylate). The acrylic acid ester accounts for preferably 60% by weight or more, more preferably 70% by weight or more, of the monomer components constituting the second molecular chain. The upper limit may be 100% by weight.

Since the first molecular chain is a molecular chain formed by reacting the chain transfer agent (a3) having a mercapto group, at either end of the first molecular chain, as a substituent derived from (a3) , —SR ⁸ . In the above formula, S represents a sulfur atom and ^R8 represents a hydrocarbon group which may have a reactive silicon group. The hydrocarbon group includes an alkyl group having 1 to 20 carbon atoms, an aryl group, an aralkyl group, and the like. The said reactive silicon group is a reactive silicon group represented by Formula (1) mentioned above. Specific examples of R ⁸ include reactive silicon group-containing methyl group, reactive silicon group-containing propyl group, n-dodecyl group, tert-dodecyl group, lauryl group and the like.

Corresponding to the molar ratio of the polyfunctional macromonomer (a2) / chain transfer agent (a3) having a mercapto group, from the viewpoint of improving the strength of the resulting cured product, a (meth) acrylic acid ester copolymer In (A), the molar ratio of the main chain skeleton of the polyfunctional macromonomer (a2) to the -SR ⁸ is preferably 0.03 or more, more preferably 0.05 or more, and 0.05 or more. 09 or more is more preferable, and 0.1 or more is particularly preferable. Although the upper limit of the molar ratio is not particularly limited, it is preferably 1 or less, more preferably 0.5 or less, and even more preferably 0.3 or less.

<Method for producing (meth)acrylate copolymer (A)>
The (meth)acrylate copolymer (A) can be produced by polymerizing the above monomer components. The polymerization method is not particularly limited, but may be general free radical polymerization. According to the present embodiment, although it is a free radical polymerization, the polymerization can be controlled, and the (meth)acrylic acid ester copolymer (A), which is a block copolymer, can be produced. , its molecular weight distribution can be relatively narrow.

Polymerization initiators that can be used in the free radical polymerization include, for example, 2,2′-azobis(2-methylbutyronitrile), dimethyl 2,2′-azobis(2-methylpropionate), 2,2 '-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis [N- (2-propenyl) -2- methyl propionamide], 1,1'-azobis (cyclohexane-1-carbonitrile) and other azo compounds; benzoyl peroxide, isobutyryl peroxide, isononanoyl peroxide, decanoyl peroxide, lauroyl peroxide, para diacyl peroxides such as chlorobenzoyl peroxide and di(3,5,5-trimethylhexanoyl) peroxide; diisopropyl purge carbonate, di-sec-butyl purge carbonate, di-2-ethylhexyl purge carbonate, di-1-methylheptyl Peroxydicarbonates such as purged carbonate, di-3-methoxybutyl purged carbonate, dicyclohexyl purged carbonate; tert-butyl perbenzoate, tert-butyl peracetate, tert-butyl per-2-ethylhexanoate, tert-butyl perisobutyl Peroxyesters such as lactate, tert-butyl perpivalate, tert-butyl diperadipate, cumyl perneodecanoate; ketone peroxides such as methyl ethyl ketone peroxide, cyclohexanone peroxide; di-tert-butyl peroxide, dicumyl peroxide, tert-butyl cumyl peroxide, dialkyl peroxides such as 1,1-di(tert-hexylperoxy)-3,3,5-trimethylcyclohexane; cumene hydroxyl peroxide, tert-butyl hydro hydroperoxides such as peroxides; peroxides such as 1,1-di(tert-hexylperoxy)-3,3,5-trimethylcyclohexane; These polymerization initiators may be used alone or in combination of two or more.

Examples of solvents that can be used in the free radical polymerization include aromatic solvents such as toluene, xylene, styrene, ethylbenzene, paradichlorobenzene, di-2-ethylhexyl phthalate, and di-n-butyl phthalate; hexane, Aliphatic hydrocarbon solvents such as heptane, octane, cyclohexane, and methylcyclohexane; carboxylic acid ester compounds such as butyl acetate, n-propyl acetate, and isopropyl acetate; ketone compounds such as methyl isobutyl ketone and methyl ethyl ketone; dimethyl carbonate, diethyl carbonate, etc. alcohol compounds such as n-propanol, 2-propanol, n-butanol, 2-butanol, isobutanol, tert-butanol, and amyl alcohol; Among them, alcohol compounds are preferable because they have a narrow molecular weight distribution. Aromatic solvents are preferred because of their high dissolving power. Aliphatic hydrocarbon solvents are preferred because of their low odor. The molecular weight distribution of the (meth)acrylate copolymer (A) is affected by the amount of the chain transfer agent (a3) added and the solvent. When the amount of chain transfer agent (a3) added is 3% by weight or less, it is greatly affected by the type of solvent. When it is desired to obtain a (meth)acrylate copolymer (A) with a narrow molecular weight distribution, isobutanol is preferably used as the solvent.

As described above, the (meth)acrylic acid ester copolymer (A) uses a monomer (a4) having a reactive silicon group and a polymerizable unsaturated group, or reacts in addition to a mercapto group By using a chain transfer agent (a3) having a reactive silicon group, it will have a reactive silicon group. Both methods may be used in combination. By using a monomer (a4) having a reactive silicon group and a polymerizable unsaturated group, reactive silicon is randomly added to the side chains of the molecular chain mainly composed of the (meth)acrylic acid ester (a1) groups can be introduced. Further, by using a chain transfer agent (a3) having a reactive silicon group in addition to a mercapto group, a reactive silicon group is added to the end of the molecular chain mainly composed of the (meth)acrylic acid ester (a1). can be introduced.

However, in order to further introduce a reactive silicon group into the (meth)acrylic acid ester copolymer (A), the following methods can be used in combination.
(iii) After copolymerizing a monomer having a reactive functional group (V group) with a (meth)acrylic acid ester (a1) or the like, the resulting copolymer is reacted with a functional group that reacts with the V group. a method of reacting a compound having a silicon group. Specifically, after copolymerizing 2-hydroxyethyl acrylate, a method of reacting an isocyanate silane compound having a reactive silicon group, or after copolymerizing glycidyl acrylate, an aminosilane compound having a reactive silicon group is used. A reaction method and the like can be exemplified.
(iv) A method of modifying terminal functional groups of a (meth)acrylic acid ester-based copolymer synthesized by a living radical polymerization method to introduce a reactive silicon group. A (meth)acrylic ester copolymer obtained by a living radical polymerization method is easy to introduce a functional group into the terminal of the polymer, and by modifying this, a reactive silicon group can be introduced into the terminal of the polymer.

Examples of the compound having a reactive silicon group and a functional group that reacts with group V used in method (iii) include 3-isocyanatopropyldimethoxymethylsilane, 3-isocyanatopropyltrimethoxysilane, and 3-isocyanatopropyltriethoxysilane. , isocyanatomethyldimethoxymethylsilane, isocyanatomethyltrimethoxysilane, isocyanatomethyltriethoxysilane; 3-glycidoxypropyldimethoxymethylsilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyl Epoxysilane compounds such as triethoxysilane, glycidoxymethyldimethoxymethylsilane, glycidoxymethyltrimethoxysilane, glycidoxymethyltriethoxysilane; 3-aminopropyldimethoxymethylsilane, 3-aminopropyltrimethoxysilane, 3 -aminopropyltriethoxysilane, aminomethyldimethoxymethylsilane, aminomethyltrimethoxysilane, aminomethyltriethoxysilane, N-cyclohexylaminomethyldimethoxymethylsilane, N-cyclohexylaminomethyltrimethoxysilane, N-cyclohexylaminomethyltriethoxysilane Examples include aminosilane compounds such as silane.

In method (iv), any modification reaction can be used. A method of introducing a double bond at the end of a polymer using a compound having a reactive group capable of reacting with a double bond and then introducing a reactive silicon group using a hydrosilylation reaction or the like.

<<Polyester (B) having a reactive silicon group>>
The curable composition according to the present embodiment can form a cured product with relatively high strength by containing the polyester (B) having a reactive silicon group. In addition, the curable composition according to the present embodiment is solid at room temperature, but can be applied to a substrate by being fluidized by heating and melting, and can be used as a hot-melt curable composition. can be done. Hereinafter, the polyester (B) having a reactive silicon group is also abbreviated as "polyester (B)".
Polyester (B) has a reactive silicon group represented by formula (1) described above. The reactive silicon group possessed by the polyester (B) may be the same as or different from the reactive silicon group possessed by the (meth)acrylate polymer (A).

Specific examples of the reactive silicon group possessed by the polyester (B) include a trimethoxysilyl group, a triethoxysilyl group, a tris(2-propenyloxy)silyl group, a triacetoxysilyl group, a dimethoxymethylsilyl group, a diethoxy methylsilyl 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 thereto.

The polyester (B) preferably has one or more reactive silicon groups on average per molecule, and particularly preferably has a reactive silicon group at both ends of the main chain skeleton of the polyester.

The polyester (B) preferably has crystallinity at room temperature because it has good compatibility with the (meth)acrylic acid ester copolymer (A). The crystallinity can be evaluated by the crystallinity of a polymer solidified by cooling at a cooling rate of 10 ° C./min from a molten state by an X-ray diffraction method (Ruland method) (for example, "polymer X-ray diffraction", written by LE Alexander, translated by Ichiro Sakurada, Kagaku Dojin, 1972, p125). The crystallinity of polyester (B) is preferably 30% or more, preferably 40% or more, and more preferably 50% or more.

The main chain skeleton of the polyester (B) can be formed by a known method such as condensation of a dibasic acid such as adipic acid and a diol, or ring-opening polymerization of lactones.
Examples of the dibasic acid include oxalic acid, malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3 , 3-diethylsuccinic acid, suberic acid, azelaic acid, sebacic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, 1,20-eicosanedicarboxylic acid, etc. Saturated aliphatic dicarboxylic acids; maleic acid, fumaric acid, citraconic acid, mesaconic acid, 2-pentenedioic acid, methylenesuccinic acid, allylmalonic acid, isopropylidene succinic acid, 2,4-hexadienedioic acid, acetylenedicarboxylic acid, etc. Saturated dicarboxylic acids; alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; phthalic acid, isophthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalene Dicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, dibenzoic acid, 4,4'-oxydibenzoic acid, diphenylmethane-4,4' -dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, 4,4'-biphenyldicarboxylic acid and other aromatic dicarboxylic acids; These dibasic acids may be used alone or in combination of two or more.
Among them, saturated aliphatic dicarboxylic acids are preferred, and succinic acid, suberic acid, adipic acid, sebacic acid and 1,12-dodecanedicarboxylic acid are more preferred. Further, when the polyester (B) has crystallinity, 1,12-dodecanedicarboxylic acid, sebacic acid, adipic acid, and succinic acid are preferable because they increase the crystallinity of the polyester.
Furthermore, polyvalent carboxylic acids such as trimellitic acid, trimesic acid and pyromellitic acid may be used in combination.

Examples of the diol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 3- methyl-1,3-butanediol, 2-methyl-1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1, 5-heptanediol, 1,7-heptanediol, 3,4-heptanediol, 3,5-heptanediol, 1,2-octanediol, 1,8-octanediol, 1,9-nonanediol, 1,2 -decanediol, 1,10-decanediol, 1,12-dodecanediol, 1,16-hexadecanediol, 1,18-octadecanediol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, 1,2-cyclopentanediol, 1,3-cyclopentanediol, 1,2-cyclododecanediol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polycaprolactonediol and the like. These diols may be used alone or in combination of two or more.
In addition, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,4-bis(β-hydroxyethoxy)benzene, 2,2-bis(4-hydroxyethoxyphenyl) in which carbon atoms are partially substituted with oxygen atoms or aromatic rings Propane and the like can also be used.
Diols having 2 to 20 carbon atoms are preferred, and diols having 2 to 10 carbon atoms are more preferred, from the viewpoint of availability and workability. In particular, ethylene glycol, 1,6-hexanediol, and butanediol are preferable from the viewpoint of availability and improvement of crystallinity of polyester.

A polyester resin having hydroxyl groups at both ends of the main chain skeleton can be obtained by carrying out a normal polycondensation reaction using the dibasic acid and the diol. Usually, the equivalent ratio of the hydroxyl group of the diol to the carboxyl group of the dibasic acid (hydroxyl group/carboxyl group) is preferably 1.02 to 1.5, more preferably 1.05 to 1.3. Specifically, the dibasic acid or its ester and the diol are esterified by polycondensation in the presence or absence of a catalyst at a temperature range of about 150 to 250° C. for about 1 to 50 hours. Alternatively, transesterification may be performed.

In the polycondensation, a polyester resin having hydroxyl groups at both ends of the molecule can be obtained by setting the number of moles of the diol charged to n+1 with respect to the number of moles of the dibasic acid charged. Also, by adjusting the numbers of n and n+1, the number average molecular weight of the polyester resin can be adjusted.

A polyester (B) having a reactive silicon group can be obtained by introducing a reactive silicon group into the polyester resin having a hydroxyl group obtained by the polycondensation.
The method for introducing a reactive silicon group into a polyester resin is not particularly limited, and a known method may be used as appropriate. A method of reacting a reactive silicon group-containing compound having In particular, a method of reacting a reactive silicon group-containing compound having an isocyanate group is preferred.
Examples of the reactive silicon group-containing compound having an isocyanate group include 3-isocyanatopropyldimethoxymethylsilane, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, isocyanatomethyldimethoxymethylsilane, isocyanatomethyltrimethoxy silane, isocyanatomethyltriethoxysilane, and the like.
When the compound is reacted with a polyester resin having a hydroxyl group, it is preferable to use a catalyst such as mercaptotin.

The number average molecular weight of the polyester (B) is not particularly limited, but from the viewpoint of the strength of the cured product and usability as a hot-melt curable composition, the polystyrene equivalent molecular weight measured by GPC is preferably 500 to 30,000. 1,000 to 20,000 is more preferred, 2,000 to 10,000 is even more preferred, and 2,000 to 4,500 is particularly preferred.

The blending amount of the polyester (B) is 1 per 100 parts by weight of the (meth)acrylic acid ester copolymer (A) from the viewpoint of the strength of the cured product and usability as a hot-melt curable composition. 80 parts by weight is preferable, 3 to 60 parts by weight is more preferable, 5 to 50 parts by weight is more preferable, and 10 to 45 parts by weight is particularly preferable.

<<Polyoxyalkylene Polymer (C) Having Reactive Silicon Group>>
The curable composition according to one embodiment of the present invention, in addition to the (meth) acrylic acid ester copolymer (A) having a reactive silicon group described above, a polyoxyalkylene polymer having a reactive silicon group Coalesced (C) (hereinafter also simply referred to as "polyoxyalkylene polymer (C)") may be contained.

<Reactive silicon group>
The polyoxyalkylene polymer (C) has a reactive silicon group represented by formula (1) described above. The reactive silicon group of the polyoxyalkylene polymer (C) may be the same as or different from the reactive silicon group of the (meth)acrylate copolymer (A).

Specific examples of the reactive silicon group possessed by the polyoxyalkylene polymer (C) include a trimethoxysilyl group, a triethoxysilyl group, a tris(2-propenyloxy)silyl group, a triacetoxysilyl group, and dimethoxymethyl 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 thereto. Among these are methyldimethoxysilyl, trimethoxysilyl, triethoxysilyl, (chloromethyl)dimethoxysilyl, (methoxymethyl)dimethoxysilyl, (methoxymethyl)diethoxysilyl, (N,N- diethylaminomethyl)dimethoxysilyl group is preferred because it exhibits high activity and gives a cured product with good mechanical properties; A trimethoxysilyl group is more preferred.

The polyoxyalkylene polymer (C) may have an average of 1 or less reactive silicon groups at one terminal site, or an average of more than 1 reactive silicon group at one terminal site may have a silicon group. Here, having more than one reactive silicon group on average at one terminal site means that the polyoxyalkylene polymer (C) has two or more reactive silicon groups at one terminal site. It shows that polyoxyalkylene is included.

A terminal site having two or more reactive silicon groups can be represented, for example, by the following general formula (2).

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

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

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

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

The polyoxyalkylene polymer (C) may have an average of 1.0 or less reactive silicon groups at one terminal site. In this case, the average number is preferably 0.4 or more, more preferably 0.5 or more, even more preferably 0.6 or more.

Moreover, the polyoxyalkylene polymer (C) may have more than 1.0 reactive silicon groups on average at one terminal site. In this case, the average number is more preferably 1.1 or more, still more preferably 1.5 or more, and even more preferably 2.0 or more. Moreover, the average number is preferably 5 or less, more preferably 3 or less.

The polyoxyalkylene polymer (C) may have reactive silicon groups in addition to the terminal sites, but if it has only the terminal sites, a rubber-like cured product exhibiting high elongation and low elastic modulus can be obtained. It is preferable because it becomes easy to be

The average number of reactive silicon groups per molecule of the polyoxyalkylene polymer (C) is preferably more than 1.0, more preferably 1.2 or more, from the viewpoint of the strength of the cured product. , is more preferably 1.3 or more, even more preferably 1.5 or more, and particularly preferably 1.7 or more. The average number may be 2.0 or less, or may be more than 2.0. From the viewpoint of elongation of the cured product, the number is preferably 6.0 or less, more preferably 5.5 or less, and most preferably 5.0 or less.

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

The main chain structure of the polyoxyalkylene polymer (C) may be linear or branched.

The number average molecular weight of the polyoxyalkylene polymer (C) is preferably 3,000 or more and 100,000 or less, more preferably 3,000 or more and 50,000 or less, and particularly preferably It is 3,000 or more and 30,000 or less.

Although the molecular weight distribution (Mw/Mn) of the polyoxyalkylene polymer (C) is not particularly limited, it is preferably narrow, specifically less than 2.0, more preferably 1.6 or less. 5 or less is more preferable, and 1.4 or less is particularly preferable. Moreover, from the viewpoint of improving various mechanical properties such as improving the durability and elongation of the cured product, it is preferably 1.2 or less. The molecular weight distribution of the polyoxyalkylene polymer (C) can be obtained from the number average molecular weight and weight average molecular weight obtained by GPC measurement.

<Method for synthesizing polyoxyalkylene polymer (C)>
The method for synthesizing the polyoxyalkylene polymer (C) is not particularly limited. To explain an example, first, an initiator having a hydroxyl group is polymerized with an epoxy compound to obtain a hydroxyl group-terminated polymer. After reacting the hydroxyl groups of the polymer with an alkali metal salt (for example, sodium methoxide), a halogenated hydrocarbon compound having a carbon-carbon unsaturated bond (for example, allyl chloride) is reacted to attach a carbon- Introduce carbon unsaturated bonds. Then, by reacting a reactive silicon group-containing hydrosilane compound (eg, dimethoxymethylsilane, trimethoxysilane), a reactive silicon group-containing polyoxyalkylene polymer (C) can be obtained.

A polyoxyalkylene polymer (C) having an average of more than 1.0 reactive silicon groups at one terminal site, which is a preferred embodiment, can be obtained as follows. After reacting the hydroxyl group of the hydroxyl-terminated polymer with the alkali metal salt in the same manner as described above, an epoxy compound having a carbon-carbon unsaturated bond (eg, allyl glycidyl ether) is first reacted, and then the carbon-carbon unsaturated bond is reacted. Two or more carbon-carbon unsaturated bonds are introduced at one end by reacting a halogenated hydrocarbon compound having a saturated bond (eg, allyl chloride). After that, a reactive silicon group-containing hydrosilane compound may be reacted.

It is also possible to introduce a reactive silicon group into the polymer by using a reactive silicon group-containing mercaptosilane instead of the reactive silicon group-containing hydrosilane compound.

The main chain of the polyoxyalkylene polymer (C) is an ester bond or the general formula (3):
-NR ⁶ -C(=O)- (3)
(wherein R ⁶ represents an organic group having 1 to 10 carbon atoms or a hydrogen atom).

A cured product obtained from a curable composition containing a polyoxyalkylene polymer (C) 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 polyoxyalkylene polymer (C) containing amide segments and the like may be cleaved by heat or the like. Moreover, a curable composition containing a polyoxyalkylene polymer (C) containing an amide segment or the like tends to have a high viscosity. Considering the above merits and demerits, as the polyoxyalkylene polymer (C), a polyoxyalkylene containing an amide segment or the like may be used, or a polyoxyalkylene containing no amide segment or the like may be used. You may

Examples of the amide segment represented by the general formula (3) include the reaction between an isocyanate group and a hydroxyl group, the reaction between an amino group and a carbonate, the reaction between an isocyanate group and an amino group, and the reaction between an isocyanate group and a mercapto group. and the like. The amide segment represented by the general formula (3) also includes those formed by the reaction of the amide segment containing an active hydrogen atom with an isocyanate group.

As an example of a method for producing the polyoxyalkylene polymer (C) containing an amide segment, a polyoxyalkylene having an active hydrogen-containing group at its terminal is reacted with a polyisocyanate compound to produce a polymer having an isocyanate group at its terminal. A compound having both a functional group (for example, a hydroxyl group, a carboxyl group, a mercapto group, a primary amino group or a secondary amino group) capable of reacting with the isocyanate group and a reactive silicon group after or simultaneously with the synthesis of the coalescence. A method of reacting is mentioned. Another example is a method of reacting a polyoxyalkylene having an active hydrogen-containing group at its end with a reactive silicon group-containing isocyanate compound.

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

A method of blending a (meth)acrylic acid ester copolymer (A) and a polyoxyalkylene polymer (C) is disclosed in JP-A-59-122541, JP-A-63-112642, and JP-A-6. -172631, Japanese Patent Application Laid-Open No. 11-116763, and the like. Alternatively, a method of polymerizing a (meth)acrylic acid ester-based monomer in the presence of a polyoxypropylene-based polymer having a reactive silicon group can be used.

When the polyoxyalkylene polymer (C) and the (meth)acrylic acid ester copolymer (A) are used in combination, the weight ratio (C):(A) is 95:5 to 50:50, that is, The proportion of (C) is preferably 50% by weight or more and 95% by weight or less. Within this range, a cured product exhibiting flexibility and high shear adhesive strength can be obtained. Further, from the viewpoint of achieving both high strength and flexibility, (C):(A) is preferably 80:20 to 50:50, more preferably 70:30 to 50:50.

<<Silanol condensation catalyst>>
The silanol condensation catalyst is an optional component, but the condensation reaction of the reactive silicon groups of the (meth)acrylic acid ester copolymer (A), the polyester (B), and the polyoxyalkylene polymer (C) It is preferable to be blended because it can promote

Examples of silanol condensation catalysts include organic tin compounds, carboxylic acid metal salts, amine compounds, carboxylic acids, and alkoxy metals.

Specific examples of organic tin compounds include dibutyltin dilaurate, dibutyltin dioctanoate, dibutyltin bis(butyl maleate), dibutyltin diacetate, dibutyltin oxide, dibutyltin bis(acetylacetonate), dioctyltin bis(acetylacetonate), phosphate), dioctyltin dilaurate, dioctyltin distearate, dioctyltin diacetate, dioctyltin oxide, reaction products of dibutyltin oxide and silicate compounds, reaction products of dioctyltin oxide and silicate compounds, dibutyltin oxide and phthalates and the like.

Specific examples of carboxylate metal salts include tin carboxylate, bismuth carboxylate, titanium carboxylate, zirconium carboxylate, and iron carboxylate. As the carboxylic acid metal salt, the following carboxylic acid 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), 1,5 - nitrogen-containing heterocyclic compounds such as diazabicyclo[4,3,0]nonene-5(DBN); guanidines such as guanidine, phenylguanidine and diphenylguanidine; butylbiguanide, 1-o-tolylbiguanide and 1-phenylbiguanide biguanides such as; amino group-containing silane coupling agents; and 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, and versatic acid.

Specific examples of alkoxy metals include titanium compounds such as tetrabutyl titanate titanium tetrakis (acetylacetonate), diisopropoxytitanium bis (ethylacetoacetate), aluminum tris (acetylacetonate), and diisopropoxyaluminum ethylacetoacetate. and zirconium compounds such as zirconium tetrakis (acetylacetonate).

When using a silanol condensation catalyst, the amount used is 100 parts by weight of the (meth)acrylic acid ester copolymer (A) from the viewpoint of promoting the condensation reaction of the reactive silicon group [however, polyoxyalkylene polymer When coalescence (C) is contained, a total of 100 parts by weight of the (meth)acrylate copolymer (A) and the polyoxyalkylene polymer (C). hereinafter the same], it is preferably 0.001 to 20 parts by weight, more preferably 0.01 to 15 parts by weight, and even more preferably 0.01 to 10 parts by weight.

<<Other Additives>>
The curable composition according to the present embodiment includes, in addition to the (meth)acrylic acid ester copolymer (A), the polyester (B), the polyoxyalkylene polymer (C), and the silanol condensation catalyst, As agents, plasticizers, fillers, adhesiveness imparting agents, dehydrating agents, rheology control agents, antioxidants, light stabilizers, ultraviolet absorbers, and other resins may be added.

In addition, various additives may be added to the curable composition according to the present embodiment as necessary for the purpose of adjusting various physical properties of the curable composition or cured product. Examples of such additives include solvents, diluents, photo-curing substances, oxygen-curing substances, surface property modifiers, silicates, curability modifiers, radical inhibitors, metal deactivators, ozone Degradation inhibitors, phosphorus-based peroxide decomposers, lubricants, pigments, antifungal agents, flame retardants, foaming agents and the like.

<Plasticizer>
The curable composition may contain a plasticizer. By blending the plasticizer, the viscosity of the curable composition can be lowered and handling becomes easier.

Examples of plasticizers include, but are not limited to, dibutyl phthalate, diisononyl phthalate (DINP), diheptyl phthalate, di(2-ethylhexyl) phthalate, diisodecyl phthalate (DIDP), and phthalate compounds such as butylbenzyl phthalate; (2-ethylhexyl)-1,4-benzenedicarboxylate and other terephthalic acid ester compounds; 1,2-cyclohexanedicarboxylic acid diisononyl ester and other non-phthalic acid ester compounds; dioctyl adipate, dioctyl sebacate, dibutyl sebacate, Aliphatic polyvalent carboxylic acid ester compounds such as diisodecyl succinate and acetyl tributyl citrate; unsaturated fatty acid ester compounds such as butyl oleate and methyl acetylricinoleate; phosphate ester compounds; trimellitate ester compounds; paraffins; hydrocarbon oils such as alkyldiphenyl and partially hydrogenated terphenyl; process oils; epoxidized soybean oil, epoxidized linseed oil, bis(2-ethylhexyl)-4,5-epoxycyclohexane-1,2-di Epoxy plasticizers such as carboxylate (E-PS), epoxyoctyl stearate, epoxybutylstearate and epoxybenzyl stearate; alkyl sulfonate esters, and the like.

Polymeric plasticizers can also be used as plasticizers. Specific examples of polymeric plasticizers include vinyl polymers; polyester plasticizers; polyether polyols such as polyethylene glycol and polypropylene glycol having a number average molecular weight of 500 or more; polyether plasticizers such as derivatives converted to polystyrenes; polybutadiene, polybutene, polyisobutylene, butadiene-acrylonitrile, polychloroprene and the like.
Among them, polymer plasticizers are preferred, polyether plasticizers are more preferred, and polypropylene glycol is particularly preferred.
As the plasticizer, only one type may be used, or two or more types may be used in combination.

The blending amount of the plasticizer is preferably 5 to 150 parts by weight, more preferably 10 to 120 parts by weight, more preferably 20 to 100 parts by weight with respect to 100 parts by weight of the (meth)acrylic acid ester copolymer (A). Parts by weight are particularly preferred.

<Filler>
A filler can be blended into the curable composition. The strength of the cured product can be improved by adding a filler.

Fillers include ground calcium carbonate, colloidal calcium carbonate, magnesium carbonate, diatomaceous earth, clay, talc, titanium oxide, fumed silica, precipitated silica, crystalline silica, fused silica, anhydrous silicic acid, hydrous silicic acid, Alumina, carbon black, ferric oxide, fine aluminum powder, zinc oxide, activated zinc white, PVC powder, PMMA powder, glass fiber and filament, and the like. Organic balloons and inorganic balloons may be added for the purpose of weight reduction (lower specific gravity) of the composition. Only one type of filler may be used, or two or more types may be used in combination.

The amount of the filler compounded is preferably 1 to 300 parts by weight, more preferably 10 to 250 parts by weight, per 100 parts by weight of the (meth)acrylate copolymer (A).

<Adhesion imparting agent>
The curable composition may contain an adhesive agent.
A silane coupling agent or a reactant of the silane coupling agent can be added as the adhesion imparting agent.

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-isocyanatopropyltrimethoxysilane, γ-isocyanatopropyltrimethoxysilane; isocyanate group-containing silanes such as ethoxysilane, γ-isocyanatopropylmethyldimethoxysilane, α-isocyanatomethyltrimethoxysilane, α-isocyanatomethyldimethoxymethylsilane; γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, mercapto group-containing silanes such as γ-mercaptopropylmethyldimethoxysilane; epoxy group-containing silanes such as γ-glycidoxypropyltrimethoxysilane and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; . Reaction products of various silane coupling agents can also be used. The adhesion imparting agent may be used alone or in combination of two or more.

The amount of the adhesion-imparting agent is preferably 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight, per 100 parts by weight of the (meth)acrylate copolymer (A).

<Dehydrating agent>
A dehydrating agent can be added to the curable composition. Here, the dehydrating agent is preferably a compound that can react with water, more preferably a silicon compound that can react with water (excluding compounds corresponding to adhesiveness-imparting agents), and particularly a trialkoxysilane compound. preferable.

Specific examples of the dehydrating agent include, but are not particularly limited to, vinyl group-containing silanes such as vinyltrimethoxysilane, vinyltriethoxysilane, and vinylmethyldimethoxysilane. Only one type of dehydrating agent may be used, or two or more types may be used.

The amount of the dehydrating agent is preferably 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight, and 1 to 10 parts by weight with respect to 100 parts by weight of the (meth)acrylate copolymer (A). 5 parts by weight is more preferred.

<Rheology control agent>
If necessary, a rheology control agent may be added to the curable composition to prevent sagging and improve workability.

The rheology control agent is not particularly limited, but examples thereof include fatty acid amide waxes, hydrogenated castor oil derivatives; metallic soaps such as calcium stearate, aluminum stearate and barium stearate; dry silica, wet silica and the like. These rheology control agents may be used alone or in combination of two or more.

The amount of the rheology control agent compounded is preferably 0.1 to 20 parts by weight per 100 parts by weight of the (meth)acrylic acid ester copolymer (A).

<Antioxidant>
An antioxidant (antiaging agent) can be used in the curable composition. The use of an antioxidant can enhance 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 content of the antioxidant is preferably 0.1 to 10 parts by weight, more preferably 0.2 to 5 parts by weight, per 100 parts by weight of the (meth)acrylate copolymer (A).

<Light stabilizer>
A light stabilizer can be used in the curable composition. The use of a light stabilizer can prevent photo-oxidative deterioration of the cured product.
Benzotriazole-based, hindered amine-based, and benzoate-based compounds can be exemplified as light stabilizers, and hindered amine-based compounds are particularly preferred.
The blending amount of the light stabilizer is preferably 0.1 to 10 parts by weight, more preferably 0.2 to 5 parts by weight, per 100 parts by weight of the (meth)acrylic acid ester copolymer (A).

<Ultraviolet absorber>
A UV absorber can be used in the curable composition. The use of an ultraviolet absorber can enhance the surface weather resistance of the cured product.
Examples of UV absorbers include benzophenone-based, benzotriazole-based, salicylate-based, substituted tolyl-based and metal chelate-based compounds, and benzotriazole-based compounds are particularly preferred. Tinuvin 327, Tinuvin 328, Tinuvin 329, and Tinuvin 571 (manufactured by BASF).
The blending amount of the ultraviolet absorber is preferably 0.1 to 10 parts by weight, more preferably 0.2 to 5 parts by weight, per 100 parts by weight of the (meth)acrylate copolymer (A).

<<Curable composition>>
The curable composition according to one embodiment of the present invention can be prepared as a one-component type in which all ingredients are pre-blended and stored in a sealed container, and cured by moisture in the air after application. In this case, it is preferable that the ingredients containing water are dehydrated and dried in advance before use, or dehydrated by decompression or the like during compounding and kneading.

Further, the curable composition according to one embodiment of the present invention includes a main agent containing a (meth)acrylic acid ester copolymer (A) and a polyester (B), a silanol condensation catalyst, a filler, a plasticizer, and water. It can also be prepared as a two-component type in which the main agent and the curing agent are mixed before use.

The method for preparing the curable composition according to one embodiment of the present invention is not particularly limited. For example, the above components are blended and kneaded at room temperature or under heating using a mixer, roll, kneader, etc., or a small amount of an appropriate solvent is used to dissolve and mix the above components. methods can be employed.

A curable composition according to an embodiment of the present invention can exhibit good adhesion to various adherends such as plastics, metals and composites. In addition, when used as an adhesive for non-polar materials such as polypropylene and engineering plastics with rigid molecular chains such as polyphenylene sulfide, in order to increase adhesion to these adherends and obtain stable adhesive strength, The adherend can be previously surface-treated by known methods. 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 release agents used during molding and remaining on the adherend surface.

Since the cured product obtained by curing the curable composition according to one embodiment of the present invention has good adhesion to various adherends, the curable composition can be used as an adhesive, a sealing It can be used as a material or an adhesive. In particular, the curable composition according to one embodiment of the present invention is solid at room temperature, but can be applied to a substrate by being fluidized by heating and melting, so it can be used as a hot-melt curable composition. can be preferably used.

The curable composition according to one embodiment of the present invention is preferably heated to a high temperature to reduce the viscosity in order to ensure workability when applied to an adherend. About 70 to 180°C is preferable, 90 to 160°C is more preferable, and 100 to 150°C is even more preferable. The heating method is not particularly limited, and conventionally known methods can be used.

The curable composition according to one embodiment of the present invention can exhibit desired physical properties by carrying out a long-term curing (curing) step after joining adherends. The conditions for the curing (curing) step are not particularly limited, but include, for example, a temperature of 5 to 90° C. and a time of 24 hours to 1 week.

When the curable composition according to one embodiment of the present invention is used as a hot-melt curable composition, it can be used as a reactive hot-melt adhesive. This curable composition can be used as an adhesive for joining panels of buses, trailers, trains, etc., as an adhesive for displays and housings in smartphones, tablet terminals, laptop computers, etc. -Also suitable for joining dissimilar materials such as composites and aluminum-composites. When dissimilar materials are joined, 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.

More specifically, the curable composition according to one embodiment of the present invention can be It is preferably used as an adhesive used in various machine parts.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the Examples are not intended to limit the present invention.

The number average molecular weight and weight average molecular weight in the examples are GPC molecular weights measured under the following conditions.
Liquid delivery system: Tosoh HLC-8120GPC
Column: TSK-GEL H type manufactured by Tosoh Solvent: THF
Molecular weight: Polystyrene equivalent Measurement temperature: 40°C

The terminal group equivalent molecular weights in the examples were obtained by determining the hydroxyl value by the measuring method of JIS K 1557, determining the iodine value by the measuring method of JIS K 0070, and determining the structure of the organic polymer (degree of branching determined by the polymerization initiator used). It is the molecular weight obtained by taking into consideration.

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

(sulfur atom concentration)
The sulfur atom concentration is a theoretical value calculated from the total amount of the monomer components used in the production of the (meth)acrylate copolymer (A) and the amount of the chain transfer agent (a3) having a mercapto group. be.

(Synthesis example 1)
Polyoxypropylene glycol with a number average molecular weight of about 4,020 (molecular weight as converted to terminal groups: 2,980) is used as an initiator, and propylene oxide is polymerized with a zinc hexacyanocobaltate glyme complex catalyst to have hydroxyl groups at both ends. , a number average molecular weight of 21,100 (termed molecular weight of terminal groups: 13,600) and a molecular weight distribution Mw/Mn of 1.21. 60 ppm of U-360 (dibutyltin bis (isooctyl mercaptopropionate, Nitto Kasei Co., Ltd.)) was added to the obtained polyoxypropylene, and Karenz AOI (2-isocyanato ethyl acrylate , Showa Denko Co., Ltd.) was dropped in an amount of 0.93 equivalents, and the mixture was reacted at 80°C for 1 hour in a nitrogen atmosphere containing 5.5% oxygen. Polyfunctional macromonomer (a2-1) which is a polyoxyalkylene polymer having about two acryloyl groups in one combined molecule), a number average molecular weight of 21,100, and a weight average molecular weight of 24,930 ).

(Synthesis example 2)
A four-necked flask equipped with a stirrer was charged with 44.8 parts by weight of isobutanol, and the temperature was raised to 105° C. under a nitrogen atmosphere. There, 41.2 parts by weight of methyl methacrylate, 4.0 parts by weight of butyl acrylate, 4.0 parts by weight of stearyl methacrylate, 4.1 parts by weight of 3-methacryloxypropyltrimethoxysilane, the polyfunctional 44.1 parts by weight of the macromonomer (a2-1), 2.6 parts by weight of 3-mercaptopropyltrimethoxysilane, and 0.9 parts by weight of 2,2'-azobis(2-methylbutyronitrile) were mixed with 28 parts by weight of isobutanol. A mixed solution dissolved in 0.5 parts by weight was added dropwise over 5 hours. Furthermore, a mixed solution of 0.3 parts by weight of 2,2'-azobis(2-methylbutyronitrile) dissolved in 9.5 parts by weight of isobutanol was added, and polymerization was carried out at 105°C for 2 hours. An isobutanol solution (solid content: 55%) of a reactive silicon group-containing (meth)acrylate copolymer (A-1) having a molecular weight of 490 (GPC) was obtained. The solid content of the solution has a polyfunctional macromonomer equivalent weight of 0.021 mmol/g, a reactive silicon group equivalent weight of 0.30 mmol/g, and a sulfur atom concentration of 4,238 ppm.

(Synthesis Example 3)
In a four-necked flask equipped with a stirrer, 100 parts by weight of HS 2H-500S (polyester polyol, manufactured by Toyokuni Oil Co., Ltd.) and Neostan U-360 (dibutyltin bis(isooctylthioglycolate), Nitto Kasei Co., Ltd. ) was added, and the temperature was raised to 90° C. under a nitrogen atmosphere. 7.5 parts by weight of 3-isocyanatopropyltrimethoxysilane was added dropwise thereto and allowed to react for 1 hour to obtain a polyester (B-1) having trimethoxysilyl groups at both ends.

(Example 1)
In an isobutanol solution of the (meth)acrylic acid ester copolymer (A-1) obtained in Synthesis Example 2, the polyester (B-1) obtained in Synthesis Example 3 is added to 100 parts by weight of the solid content. After mixing to 30 weight, isobutanol was heated to devolatilize to obtain a curable composition which is solid at room temperature.

(Tensile properties)
130 parts by weight of the resulting curable composition was heated and melted at 130° C., and 2 parts by weight of KBM-603 (N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.) was added. , and 0.2 parts by weight of U-810 (dioctyltin dilaurate, manufactured by Nitto Kasei Co., Ltd.) are added and mixed to prepare a sheet having a thickness of about 2 mm, and cured for 7 days under conditions of 23° C. and 50% RH. did The resulting sheet was punched into a No. 1 dumbbell shape (JIS K 6251) and subjected to a tensile strength test at 23°C and 50% RH to measure the stress at 30% elongation (M30) and the strength at break (TB). . Tensile physical properties were measured using an Autograph (AGS-X) manufactured by Shimadzu Corporation at a tensile speed of 50 mm/min. Table 1 shows the results.

(Comparative example 1)
Without using the polyester (B-1), isobutanol was heated and devolatilized from the isobutanol solution of the (meth)acrylic acid ester copolymer (A-1) obtained in Synthesis Example 2, and the copolymer obtained Using 100 parts by weight of polymer (A-1), a tensile strength test was conducted in the same manner as above. Table 1 shows the results obtained.

From Table 1, the curable composition of Example 1 containing the reactive silicon group-containing (meth)acrylic acid ester copolymer (A) and the reactive silicon group-containing polyester (B) was subjected to the reaction of Comparative Example 1. It can be seen that a cured product having a higher tensile strength than the (A) silicon group-containing (meth)acrylic acid ester copolymer is formed.

Claims (7)

(Meth)acrylic acid ester copolymer (A) having a reactive silicon group represented by the following general formula (1), and
Containing a polyester (B) having a reactive silicon group represented by the following general formula (1),
The monomer component constituting the (meth)acrylic acid ester copolymer (A) is
(meth) acrylic acid ester (a1),
A polymer (a2) having more than one (meth)acryloyl group in the molecule, and
containing a chain transfer agent (a3) having a mercapto group,
The monomer component further contains a monomer (a4) having a reactive silicon group and a polymerizable unsaturated group, and/or the chain transfer agent (a3) having a mercapto group is a reactive silicon A curable composition further comprising a group.
—SiR ¹ _3-a X _a (1)
(Wherein, R ¹ represents a substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms; X represents a hydroxyl group or a hydrolyzable group; a is 2 or 3.) 2. The curable composition according to claim 1, wherein the polymer (a2) is a polyoxyalkylene polymer (a2'') having more than one (meth)acryloyl group in the molecule. 2. The curable composition according to claim 1, wherein the polymer (a2) is a (meth)acrylate polymer (a2') having more than one (meth)acryloyl group in the molecule. 4. The curable composition according to any one of claims 1 to 3, wherein the molar ratio of polymer (a2)/chain transfer agent (a3) having a mercapto group is 0.05 or more. The curable composition according to any one of claims 1 to 4, wherein the polyester (B) has crystallinity. The curable composition according to any one of claims 1 to 5, which is a hot-melt curable composition. A cured product obtained by curing the curable composition according to any one of claims 1 to 6.