JP5423426B2 - Curable composition - Google Patents

Description

  The present invention contains a specific methacrylic copolymer and a curing accelerator, is cured with moisture in the air, and gives a cured product excellent in adhesion to an adherend made of a resin or the like and tensile properties. The present invention relates to a curable composition. Further, the present invention provides a compatibility between the methacrylic copolymer and the oxyalkylene polymer without using a compatibilizing agent when an oxyalkylene polymer having a hydrolyzable silyl group is blended. The present invention relates to an excellent curable composition.

  Conventionally, a polymer having a functional group at a side chain or terminal is crosslinked by itself or in combination with a curing agent to give a cured product excellent in adhesiveness, heat resistance, durability, and the like. ing. Among them, a polymer having a crosslinkable silyl group is a typical one. For example, a polymer having a crosslinkable silyl group at the end absorbs moisture in the air in the presence of an appropriate curing agent. Gives a cured product.

  The main chain skeleton of such a polymer having a crosslinkable silyl group includes: (meth) acrylic acid ester polymer; polyether polymer such as polyethylene oxide, polypropylene oxide, polytetramethylene oxide; polybutadiene, poly Hydrocarbon polymers such as isoprene, polychloroprene, polyisobutylene or hydrogenated products thereof; polyester polymers such as polyethylene terephthalate, polybutylene terephthalate, polycaprolactone, etc. are known, and the main chain skeleton and cross-linked form It is used for various purposes.

Patent documents 1 and 2 are known as a curable composition which gives the hardened material which uses a (meth) acrylic acid ester system polymer.
In Patent Document 1, an oxyalkylene polymer having a silicon-containing functional group that can be crosslinked by forming a siloxane bond, which gives a cured product having excellent mechanical properties and adhesive properties, is crosslinked by forming a siloxane bond. Having a silicon-containing functional group and a molecular chain substantially having a (meth) acrylic acid alkyl ester monomer unit having an alkyl group having 1 to 2 carbon atoms and an alkyl group having 7 to 9 carbon atoms A curable resin composition containing a copolymer composed of (meth) acrylic acid alkyl ester monomer units and a curing accelerator is disclosed.

  Further, Patent Document 2 is a composition that gives sufficient extensibility as a sealing material and tensile strength, and gives excellent adhesion to an adherend that is difficult to adhere, such as a fluororesin steel plate. A polymer whose main chain is essentially a polyalkylene oxide and having a hydrolyzable silyl group which can be crosslinked at the terminal, an acrylic copolymer having a hydrolyzable silyl group which can be crosslinked, and an amino group And a compound having an alkoxysilyl group, and a room temperature curable composition are disclosed.

International Publication WO 03/035755 JP-A-8-225707

When preparing a curable composition using a (meth) acrylic polymer and an oxyalkylene polymer, depending on the configuration of the (meth) acrylic polymer, the compatibility of both is not sufficient, The composition may become cloudy. Moreover, even if it was excellent in compatibility, the cured | curing material excellent in the adhesiveness with a to-be-adhered body, and a tensile characteristic might not be obtained.
The object of the present invention is to provide a cured product that contains a methacrylic copolymer and a curing accelerator, cures with moisture in the air, and gives a cured product having excellent adhesion and adherence to an adherend made of a resin or the like. The composition (moisture curable composition), and further, the present invention, when blended with an oxyalkylene polymer having a hydrolyzable silyl group, without using a compatibilizing agent, It is to provide a curable composition excellent in compatibility with the oxyalkylene polymer.

The present invention is as follows.
1. In the curable composition containing (A) a methacrylic copolymer , (B) a curing accelerator and (C) an oxyalkylene polymer having a hydrolyzable silyl group , the methacrylic copolymer (A) is: , A structural unit derived from butyl methacrylate (a1), a structural unit derived from methyl acrylate, a structural unit derived from methyl methacrylate, a structural unit derived from ethyl acrylate, and a structure derived from ethyl methacrylate It has at least one kind of structural unit (a2) selected from the units and a hydrolyzable silyl group, and the content ratio of the structural unit (a1) and the structural unit (a2) is 100 mass in total. %, 35 to 90% by mass and 10 to 65% by mass, respectively, and the methacrylic copolymer (A) has a number average molecular weight of 2,000 to 10%. The curable composition characterized by being 1,000,000.
2. The content ratio of the methacrylic copolymer (A) and the oxyalkylene polymer (C) is 20 to 90% by mass and 10 to 80% by mass, respectively, when the total of both is 100% by mass. The curable composition according to 1 above.
3. The curable composition according to 1 or 2 above, wherein the content of the curing accelerator (B) is 0.01 to 20 parts by mass when the methacrylic copolymer (A) is 100 parts by mass. .
4). The curable composition according to any one of the above 1 to 3, which is used as an adhesive or a sealing agent.
5 . The methacrylic copolymer (A) is a polymerizable copolymer having butyl methacrylate, at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate, and a hydrolyzable silyl group. Any one of the above 1 to 4 , which is a polymer obtained by polymerizing a monomer mixture containing a saturated compound and a polymerization initiator at a temperature of 150 ° C. to 350 ° C. while continuously supplying it to the reaction system A curable composition according to any one of the above.
6 . The methacrylic copolymer (A) is produced by living radical polymerization of a monomer component containing butyl methacrylate and at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate. 5. The curable composition according to any one of 1 to 4 above, which is an obtained polymer.

According to the curable composition of the present invention, since it contains a specific methacrylic copolymer , a curing accelerator, and (C) an oxyalkylene polymer having a hydrolyzable silyl group, it is cured with moisture in the air. In addition, it is possible to obtain a cured product excellent in adhesiveness and tensile properties to an adherend made of a resin or the like.
The compositions of the present invention, further, because it contains oxyalkylene polymer (C) having a hydrolyzable silyl group, without using a compatibilizing agent, the methacrylic copolymer and the oxyalkylene A curable composition having excellent compatibility with a polymer can be obtained, and cured with moisture in the air to obtain a cured product having excellent adhesion to an adherend made of a resin and tensile properties. it can. And when the content rate of the said methacrylic copolymer (A) and the said oxyalkylene type polymer (C) makes both total 100 mass%, 20-90 mass% and 10-80 mass respectively. because it is%, the performance is particularly excellent.

  Furthermore, in the case where the methacrylic copolymer (A) is a polymer obtained by a specific production method, the physical properties are compared with the case where a conventionally known polymer is used. From this, a stable composition can be formed.

The present invention will be described in detail below.
In the present specification, “(meth) acryl” means acryl and methacryl, and “(co) polymer” means a homopolymer and a copolymer.
In addition, the number average molecular weight (hereinafter sometimes referred to as “Mn”) and the weight average molecular weight (hereinafter sometimes referred to as “Mw”) of the polymer are both determined by gel permeation chromatography (GPC). ) Measured in terms of polystyrene.

The curable composition of the present invention is a curable composition containing (A) a methacrylic copolymer , (B) a curing accelerator and (C) an oxyalkylene polymer having a hydrolyzable silyl group. The methacrylic copolymer (A) has a structural unit (a1) derived from butyl methacrylate, a structural unit derived from methyl acrylate, a structural unit derived from methyl methacrylate, a structural unit derived from ethyl acrylate, And having at least one structural unit (a2) selected from structural units derived from ethyl methacrylate and a hydrolyzable silyl group, and containing the structural unit (a1) and the structural unit (a2) The proportions are 35 to 90% by mass and 10 to 65% by mass, respectively, when the total of both is 100% by mass, and the number average fraction of the methacrylic copolymer (A). The number of children is 2,000 to 10,000.

（式中、Ｒ^１は、それぞれ、独立に、炭化水素基であり、Ｘは、それぞれ、独立に、ハロゲン原子、水素原子、ヒドロキシル基、アルコキシ基、アシルオキシ基、ケトキシメート基、アミド基、酸アミド基、メルカプト基、アルケニルオキシ基及びアミノオキシ基より選ばれる反応性基であり、ｎは、０、１又は２である。） The hydrolyzable silyl group contained in the methacrylic copolymer (A) has a silicon atom, a hydroxyl group and / or a hydrolyzable functional group bonded to the silicon atom, and a curing accelerator (B ) Is a group capable of forming a siloxane bond and forming a crosslinked structure. Although it does not specifically limit as a hydrolysable silyl group, The group represented by following General formula (1) from the point which is easy to bridge | crosslink is preferable.

(Wherein R ¹ is independently a hydrocarbon group, and X is independently a halogen atom, hydrogen atom, hydroxyl group, alkoxy group, acyloxy group, ketoximate group, amide group, acid amide) A reactive group selected from a group, a mercapto group, an alkenyloxy group and an aminooxy group, and n is 0, 1 or 2.)

In the general formula (1), R ¹ is preferably an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 0 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. When n = 2, the plurality of R ¹ may be the same as or different from each other.
When n = 0 or 1, the plurality of Xs may be the same as or different from each other. X in the general formula (1) is preferably an alkoxy group.

  When the methacrylic copolymer (A) contains a hydrolyzable silyl group, Si—O—Si bonds are formed by hydrolysis condensation, and a cured product such as a film having excellent strength may be formed. it can.

  The average value f (Si) of the number of hydrolyzable silyl groups contained in the methacrylic copolymer (A) is preferably 0.5 from the viewpoint of adhesion to the adherend and tensile properties of the cured product. -3.0, More preferably, it is 1.0-2.8, More preferably, it is 1.5-2.5. When this f (Si) is too small, the crosslink density of the obtained cured product is lowered, and the adhesion to the adherend may not be sufficient. On the other hand, if f (Si) is too large, the crosslinking density becomes too high, and a cured product that is brittle and inferior in impact resistance may be formed. The method for calculating f (Si) will be described later.

The position of the hydrolyzable silyl group contained in the methacrylic copolymer (A) is not particularly limited, and can be a side chain and / or a terminal of the polymer.
When the hydrolyzable silyl group is present in the side chain of the polymer, the structural unit containing the hydrolyzable silyl group is a compound having a polymerizable unsaturated bond and a hydrolyzable silyl group (hereinafter referred to as “hydrolysis”). Or a polymerizable unsaturated compound having a polymerizable silyl group.).

（式中、Ｒ^３は、水素原子又はメチル基であり、Ｒ^４は、それぞれ、独立に、炭素数１〜２０の炭化水素基であり、Ｚは、直接結合、又は、−ＣＯＯＲ^６−（Ｒ^６は、炭素数１〜６の２価のアルキレン基）、−ＣＨ_２Ｃ_６Ｈ_４ＣＨ_２ＣＨ_２−、−ＣＨ_２ＯＣＯＣ_６Ｈ_４ＣＯＯ（ＣＨ_２）_３−等の２価の有機基であり、Ｘは、それぞれ、独立に、ハロゲン原子、水素原子、ヒドロキシル基、アルコキシ基、アシルオキシ基、ケトキシメート基、アミド基、酸アミド基、メルカプト基、アルケニルオキシ基及びアミノオキシ基より選ばれる反応性基であり、ｍは、０、１又は２である。） Examples of the compound having a polymerizable unsaturated bond and a hydrolyzable silyl group (polymerizable unsaturated compound having a hydrolyzable silyl group) include compounds represented by the following general formula (2).

(In the formula, R ³ is a hydrogen atom or a methyl group, R ⁴ is each independently a hydrocarbon group having 1 to 20 carbon atoms, and Z is a direct bond or —COOR ⁶ — ( R ⁶ is a divalent organic group having 1 to 6 carbon atoms), —CH ₂ C ₆ H ₄ CH ₂ CH ₂ —, —CH ₂ OCOC ₆ H ₄ COO (CH ₂ ) ₃ — and the like. Each X is independently selected from a halogen atom, a hydrogen atom, a hydroxyl group, an alkoxy group, an acyloxy group, a ketoximate group, an amide group, an acid amide group, a mercapto group, an alkenyloxy group, and an aminooxy group. A reactive group, and m is 0, 1 or 2.)

The hydrocarbon group having 1 to 20 carbon atoms represented by R ⁴ in the general formula (2) is preferably an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 0 carbon atoms, or an aralkyl having 7 to 20 carbon atoms. It is a group. When m = 2, the plurality of R ² may be the same as or different from each other.
When m = 0 or 1, the plurality of Xs may be the same as or different from each other.

Examples of the polymerizable unsaturated compound having a hydrolyzable silyl group represented by the general formula (2) include CH ₂ ═CHSi (CH ₃ ) (OCH ₃ ) ₂ , CH ₂ ═CHSi (CH ₃ ) Cl _2. CH ₂ = CHSi (OCH ₃ ) ₃ , CH ₂ = CHSiCl ₃ , CH ₂ = CHCOO (CH ₂ ) ₂ Si (CH ₃ ) (OCH ₃ ) ₂ , CH ₂ = CHCOO (CH ₂ ) ₂ Si (OCH ₃ ) ₃ , CH ₂ = CHCOO (CH ₂ ) ₂ Si (CH ₃ ) Cl ₂ , CH ₂ = CHCOO (CH ₂ ) ₂ SiCl ₃ , CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₂ Si (CH ₃ ) ) (OCH ₃ ) ₂ , CH ₂ ═C (CH ₃ ) COO (CH ₂ ) ₂ Si (OCH ₃ ) ₃ , CH ₂ ═C (CH ₃ ) COO (CH ₂ ) ₃ Si (CH ₃ ) (O _{CH 3) 2, CH 2 =} C (CH 3) COO (CH 2) 3 Si (OCH 3) 3, CH 2 = C (CH 3) COO (CH 2) 2 Si (CH 3) Cl 2, CH 2 _{= C (CH 3) COO (} CH 2) 2 SiCl 3, CH 2 = CHCH 2 OC (O) -Ph-COO (CH 2) 3 Si (CH 3) (OCH 3) 2, CH 2 = CHCH 2 OC _{(O) -Ph-COO (CH} 2) 3 Si (OCH 3) 3, CH 2 = CHCH 2 OC (O) -Ph-COO (CH 2) 3 Si (CH 3) Cl 2, CH 2 = CHCH 2 _{OC (O) -Ph-COO (} CH 2) 3 SiCl 3 , and the like. “Ph” means a paraphenylene group.

  Moreover, in order to make the said hydrolyzable silyl group exist in the terminal of a polymer, the method using residues, such as a living polymerization initiator, a reactive silyl group containing thiol compound, etc. is applied. For example, as a polymer production method using living radical polymerization, an atom transfer radical polymerization (ATRP) method disclosed in JP-A-11-130931 and a tellurium metal disclosed in JP-A-2009-215472 are used. A method using the initiator used, a reversible addition-fragmentation chain transfer polymerization (RAFT) method disclosed in JP-T-2006-503971, and a method utilizing a nitroxide radical disclosed in JP-A-9-511786 For example, a method of introducing a hydrolyzable silyl group at the terminal after obtaining a (meth) acrylic copolymer by a method is known. Further, as a method for producing a polymer having a hydrolyzable silyl group at the terminal using a reactive silyl group-containing thiol compound, a method disclosed in JP-A-2001-40037, that is, a metallocene compound, A method of polymerizing a polymerizable (meth) acrylic monomer in the presence of at least one reactive silyl monomer in the molecule is known.

  As described above, the methacrylic copolymer (A) includes a structural unit (a1) derived from butyl methacrylate, a structural unit derived from methyl acrylate, a structural unit derived from methyl methacrylate, and ethyl acrylate. And at least one structural unit (a2) selected from structural units derived from ethyl methacrylate. This copolymer may be a random copolymer or a block copolymer.

The content ratios of the structural unit (a1) and the structural unit (a2) are 35 to 90% by mass and 10 to 65 % by mass, respectively, preferably 30 to 75, when the total of both is 100% by mass. It is 35 mass% and 25-70 mass%, More preferably, it is 35-65 mass% and 35-65 mass%. By using a methacrylic copolymer (A) having a structural unit with a content ratio in the above range, it is cured with moisture in the air, and is excellent in adhesion to an adherend composed of a resin and the like and tensile properties of the cured product. It can be set as the curable composition. Further, when the methacrylic copolymer (A) having the above structure is used, the compatibility with the oxyalkylene polymer, specifically, the oxyalkylene polymer (C) having a hydrolyzable silyl group, which will be described later. It is possible to form a curable composition excellent in the above.

  The methacrylic copolymer (A) may contain other structural units (hereinafter referred to as “structural unit (a3)”) in addition to the structural units (a1) and (a2). When the methacrylic copolymer (A) includes the structural unit (a3), the upper limit of the content is preferably 50% by mass, more preferably 40% by mass when the total amount of the structural units is 100% by mass. %.

  The structural unit (a3) is not particularly limited as long as it is derived from a polymerizable unsaturated compound. For example, (meth) acrylic acid, n-propyl (meth) acrylate, isopropyl (meth) acrylate, N-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, n-heptyl (meth) acrylate, N-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, phenyl (meth) acrylate, (meth) acrylic Acid toluyl, benzyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, (meth) acrylic acid -Methoxypropyl, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, stearyl (meth) acrylate, glycidyl (meth) acrylate, 2-aminoethyl (meth) acrylate, (meth ) Ethylene oxide adduct of acrylic acid, trifluoromethylmethyl (meth) acrylate, 2-trifluoromethylethyl (meth) acrylate, 2-perfluoroethylethyl (meth) acrylate, 2- (meth) acrylic acid 2- Perfluoroethyl-2-perfluorobutylethyl, 2-perfluoroethyl (meth) acrylate, perfluoromethyl (meth) acrylate, diperfluoromethylmethyl (meth) acrylate, 2-par (meth) acrylate Fluoromethyl-2-perfluoroethylmethyl, (meth) a (Meth) acrylic acid monomers such as 2-perfluorohexylethyl laurate, 2-perfluorodecylethyl (meth) acrylate, 2-perfluorohexadecylethyl (meth) acrylate; styrene, vinyltoluene, α- Styrenic monomers such as methylstyrene, chlorostyrene, styrenesulfonic acid and salts thereof; fluorine-containing vinyl monomers such as perfluoroethylene, perfluoropropylene and vinylidene fluoride; maleic anhydride, maleic acid, monoalkyl esters of maleic acid and Dialkyl esters; fumaric acid, monoalkyl esters and dialkyl esters of fumaric acid; maleimide, methylmaleimide, ethylmaleimide, propylmaleimide, butylmaleimide, hexylmaleimide, octylmaleimide, dodecylmale Maleimide monomers such as styrene, maleylimide, phenylmaleimide, cyclohexylmaleimide; vinyl monomers containing nitrile groups such as acrylonitrile and methacrylonitrile; vinyl monomers containing amide groups such as acrylamide and methacrylamide; vinyl acetate, vinyl propionate, Examples include vinyl esters such as vinyl pivalate, vinyl benzoate, and vinyl cinnamate; alkenes such as ethylene and propylene; conjugated dienes such as butadiene and isoprene; vinyl chloride, vinylidene chloride, allyl chloride, and allyl alcohol. These compounds can be used alone or in combination of two or more.

  The number average molecular weight (Mn) of the methacrylic copolymer (A) is 2,000 to 10,000, preferably 2,500 to 8,000, more preferably 3,000 to 6,000. . By using a composition containing a methacrylic copolymer (A) having Mn in the above range, a cured product excellent in adhesion to an adherend, mechanical properties, and the like can be obtained. Moreover, the composition containing the methacrylic copolymer (A) having Mn in this range has a suitable viscosity when applied to the use described later. In addition, when the polymer with too large Mn is used, the viscosity of the composition obtained is high, and the coating property when applied to the use etc. mentioned later may fall. On the other hand, when a polymer having too small Mn is used, the adhesiveness to the substrate may be lowered when applied to the use described later.

  The polydispersity (Mw / Mn) calculated from the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the methacrylic copolymer (A) is preferably 1.1 to 3.5. Preferably it is 1.2-3.0, More preferably, it is 1.2-2.5. By using a composition containing a methacrylic copolymer (A) having a polydispersity in the above range, excellent adhesive strength can be obtained. Moreover, this composition has a suitable viscosity at the time of applying to the use etc. which are mentioned later.

  A detailed method for producing the methacrylic copolymer (A) will be described later.

Next, the said hardening accelerator (B) will not be specifically limited if it is a component which accelerates | stimulates moisture hardening reaction.
The curing accelerator (B) includes: an organic tin compound; an organic titanium compound; an organic aluminum compound; an organic zirconium compound; an organic iron compound; an organic vanadium compound; A saturated or unsaturated polyvalent carboxylic acid and acid anhydride thereof; a reaction product (salt, etc.) of a carboxylic acid compound and an amine compound, and the like. These may be used alone or in combination of two or more.

  Examples of the organic tin compounds include dibutyltin dilaurate, dibutyltin maleate, dibutyltin diacetate, dioctyltin maleate, dibutyltin phthalate, and dibutyltin bis (alkyl maleate); tin octylate, oleic acid Divalent tin carboxylates such as tin, tin stearate, tin naphthenate, tin stearate and tin versatate; alkoxide derivatives of dialkyl tin such as dibutyltin dimethoxide and dibutyltin diphenoxide; dibutyltin diacetylacetonate and dibutyltin Intramolecular coordination derivatives (chelate compounds) of dialkyltin such as acetoacetate; reaction products of dibutyltin oxide and phthalates, reaction products of dibutyltin oxide and ester compounds such as dibutyltin oxide and The reaction product according to Riketo compounds.

  Examples of the organic titanium compounds include titanium alkoxides such as tetramethyl titanate, tetraethyl titanate, tetrapropyl titanate, tetraisopropyl titanate, tetrabutyl titanate, tetra (2-ethylhexyl titanate); titanium tetraacetylacetonate, titanium ethyl acetoacetate, etc. Chelate compounds; and triethanolamine titanate.

  Examples of the organoaluminum compound include aluminum alkoxides such as aluminum isopropylate, monosec-butoxyaluminum diisopropylate, and aluminum sec-butyrate; aluminum trisacetylacetonate, aluminum trisethylacetoacetate, diisopropoxyaluminum ethylacetoacetate, and the like. Examples include chelate compounds.

  Examples of the organic zirconium compound include zirconium alkoxides such as zirconium tetraisopropoxide and zirconium tetrabutoxide; zirconium monoacetylacetonate, zirconium bisacetylacetonate, zirconium tetraacetylacetonate, zirconium acetylacetonate bisethylacetoacetate, zirconium Examples include chelate compounds such as acetate.

  Examples of the organic iron compound include iron 2-ethylhexanoate (divalent), iron 2-ethylhexanoate (trivalent), iron neodecanoate (divalent), iron neodecanoate (trivalent), and iron oleate (2 Carboxylic acid iron salts such as iron oleate (trivalent), iron naphthenate (divalent), and iron naphthenate (trivalent).

  Examples of the amine compound include butylamine, octylamine, laurylamine, dibutylamine, monoethanolamine, diethanolamine, triethanolamine, diethylenetriamine, triethylenetetramine, oleylamine, cyclohexylamine, benzylamine, diethylaminopropylamine, xylylenediamine, Ethylenediamine, dibutylamine-2-ethylhexoate, guanidine, diphenylguanidine, 2,4,6-tris (dimethylaminomethyl) phenol, morpholine, N-methylmorpholine, 2-ethyl-4-methylimidazole, 1,8 -Diazabicyclo (5, 4, 0) undecene-7 (DBU) etc. are mentioned.

  As said hardening accelerator (B), the organotin compound is preferable from a reactive viewpoint of a curable composition.

  The content of the curing accelerator (B) contained in the curable composition of the present invention is preferably 0.01 to 20 parts by mass, more preferably 100 parts by mass with respect to the methacrylic copolymer (A). Is 0.1 to 10 parts by mass. When content of the said hardening accelerator (B) exists in the said range, hardening reaction can be advanced efficiently and the hardened | cured material which was more excellent in the adhesiveness to a to-be-adhered body, and a tensile characteristic can be obtained.

  The curable composition of the present invention is used in combination with the methacrylic copolymer (A) in order to form a cured product excellent in adhesion to an adherend composed of a resin and the like and tensile properties. An oxyalkylene polymer (C) having a hydrolyzable silyl group is contained. By using this oxyalkylene polymer (C), a curable composition having excellent compatibility between the methacrylic copolymer (A) and the oxyalkylene polymer (C) without using a compatibilizing agent. It can be. And compared with the case where the said methacrylic copolymer (A) is used independently, the hardened | cured material more excellent in the adhesiveness to the to-be-adhered body which consists of resin etc. and a tensile characteristic can be obtained.

The oxyalkylene polymer (C) is not particularly limited as long as it contains a repeating unit represented by the following general formula (3).
^-O-R 7 - (3)
(In the formula, R ⁷ is a divalent hydrocarbon group.)

As R ⁷ in the general formula (3), —CH (CH ₃ ) —CH ₂ —, —CH (C ₂ H ₅ ) —CH ₂ —, —C (CH ₃ ) ₂ —CH ₂ —, —CH ₂ CH ₂ CH ₂ CH ₂ — and the like. Of these, —CH (CH ₃ ) —CH ₂ — is preferred. In addition, the said oxyalkylene type polymer (C) may contain the said repeating unit individually by 1 type, and may contain it in 2 or more types of combinations.

  The hydrolyzable silyl group contained in the methacrylic copolymer (A) can be applied as it is to the hydrolyzable silyl group contained in the oxyalkylene polymer (C).

  The average value of the number of hydrolyzable silyl groups contained in the oxyalkylene polymer (C) is preferably 1 to 4, more preferably from the viewpoints of adhesion to the adherend and tensile properties of the cured product. Is 1.5-3.

The position of the hydrolyzable silyl group contained in the oxyalkylene polymer (C) is not particularly limited, and can be a side chain and / or a terminal of the polymer.
The oxyalkylene polymer (C) may be either a linear polymer or a branched polymer. Moreover, you may use combining these.

  The number average molecular weight (Mn) of the oxyalkylene polymer (C) is preferably 3,000 to 60,000, more preferably 4,000 to 50,000, and still more preferably 5,000 to 40,000. is there. By using a composition containing an oxyalkylene polymer (C) having Mn in the above range, a cured product having excellent tensile properties can be obtained. Moreover, this composition has a suitable viscosity at the time of applying to the use etc. which are mentioned later.

  The content ratio of the methacrylic copolymer (A) and the oxyalkylene polymer (C) is preferably 20 to 90% by mass and 10 to 80% by mass, respectively, when the total of both is 100% by mass. %, More preferably 30 to 70% by mass and 30 to 70% by mass. By using a composition containing the methacrylic copolymer (A) and the oxyalkylene polymer (C) in the above proportions, curing that is superior in adhesiveness and tensile properties to an adherend made of a resin or the like. You can get things.

  The curable composition of the present invention can contain other polymers except for the methacrylic copolymer (A) and the oxyalkylene polymer (C) as long as the effect is not impaired. . The upper limit of the content of the other polymer is usually 75 parts by mass, preferably 50 parts by mass with respect to 100 parts by mass of the methacrylic copolymer (A).

  Other polymers include (meth) acrylic (co) polymers excluding the methacrylic copolymer (A), such as the structural units (a1) and (a2), hydrolyzable silyl groups, and the like. And a methacrylic copolymer having a Mn of less than 2,000 or more than 10,000; a structure derived from an alkyl (meth) acrylate except for the structural units (a1) and (a2) Examples include (meth) acrylic copolymers having units and hydrolyzable silyl groups.

  The curable composition of the present invention may further comprise a filler, a plasticizer, an antioxidant, an ultraviolet absorber, a flame retardant, an antifoaming agent, a lubricant, a weathering stabilizer, a light stabilizer, depending on the purpose and application. Addition of heat stabilizers, colorants (pigments, dyes, etc.), fluorescent brighteners, tackifiers, anti-sagging agents, conductivity-imparting agents, antistatic agents, water repellents, oil repellents, preservatives, dehydrating agents, etc. An agent, an organic solvent, or the like can be contained.

  Examples of the filler include heavy calcium carbonate, colloidal calcium carbonate, light calcium carbonate, magnesium carbonate, zinc carbonate, aluminum hydroxide, magnesium hydroxide, carbon black, clay, talc, fumed silica, calcined silica, precipitated silica, Ground silica, fused silica, kaolin, diatomaceous earth, zeolite, titanium oxide, quicklime, iron oxide, zinc oxide, barium oxide, aluminum oxide, magnesium oxide, aluminum sulfate, glass fiber, carbon fiber, glass balloon, shirasu balloon, saran Examples include balloons and phenol balloons. These can be used alone or in combination of two or more.

  When the curable composition of the present invention contains a filler, the content thereof is preferably 20 to 300 parts by mass with respect to 100 parts by mass of all the polymers including the methacrylic copolymer (A). More preferably, it is 30-200 mass parts.

  Examples of the plasticizer include phthalic acid ester, trimellitic acid ester, pyromellitic acid ester, aliphatic monobasic acid ester, aliphatic dibasic acid ester, phosphoric acid ester, polyhydric alcohol ester, epoxy plasticizer, high Examples include molecular plasticizers and chlorinated paraffins. These can be used alone or in combination of two or more.

  Examples of the phthalic acid esters include dimethyl phthalate, diethyl phthalate, dipropyl phthalate, diisopropyl phthalate, dibutyl phthalate, diisobutyl phthalate, diamyl phthalate, di-n-hexyl phthalate, dicyclohexyl phthalate, and diheptyl phthalate. Di-n-octyl phthalate, dinonyl phthalate, diisononyl phthalate, diisodecyl phthalate, diundecyl phthalate, ditridecyl phthalate, diphenyl phthalate, di (2-ethylhexyl) phthalate, di (2-butoxyethyl phthalate) ), Benzyl 2-ethylhexyl phthalate, benzyl n-butyl phthalate, benzylisononyl phthalate, dimethyl isophthalate and the like.

  Examples of trimellitic acid esters include tributyl trimellitic acid, trihexyl trimellitic acid, tri-n-octyl trimellitic acid, tri-2-ethylhexyl trimellitic acid, and triisodecyl trimellitic acid.

  Examples of the pyromellitic acid ester include tetrabutyl pyromellitic acid, tetrahexyl pyromellitic acid, tetra-n-octyl pyromellitic acid, tetra-2-ethylhexyl pyromellitic acid, tetradecyl pyromellitic acid, and the like.

  Examples of the aliphatic monobasic ester include butyl oleate, methyl oleate, methyl octoate, butyl octoate, methyl dodecanoate, butyl dodecanoate, methyl palmitate, butyl palmitate, methyl stearate, butyl stearate, Examples thereof include methyl linoleate, butyl linoleate, methyl isostearate, butyl isostearate, methyl acetyl ricinolate, and butyl acetyl ricinolate.

  Examples of the aliphatic dibasic acid ester include dimethyl adipate, diethyl adipate, di-n-propyl adipate, diisopropyl adipate, diisobutyl adipate, di-n-octyl adipate, di (2-ethylhexyl) adipate , Diisononyl adipate, diisodecyl adipate, di (2-butoxyethyl) adipate, di (butyl diglycol) adipate, heptylnonyl adipate, dimethyl azelate, di-n-octyl azelate, di (2- Ethylhexyl), diethyl succinate, dimethyl sebacate, diethyl sebacate, dibutyl sebacate, di-n-octyl sebacate, di (2-ethylhexyl) sebacate, dibutyl fumarate, di (2-ethylhexyl) fumarate, malee Dimethyl acid Diethyl maleate, di -n- butyl, maleate, di (2-ethylhexyl), and the like.

  Examples of the phosphate ester include trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri-n-amyl phosphate, triphenyl phosphate, tri-o-cresyl phosphate, trixylenyl phosphate, and diphenyl 2-ethylhexyl phosphate. , Diphenyl cresyl phosphate, tris phosphate (2-butoxyethyl), tris phosphate (2-ethylhexyl) and the like.

  Examples of the polyhydric alcohol ester include diethylene glycol diacetylate, diethylene glycol dibenzoate, glycerol monooleate, glycerol tributyrate, glycerol triacetate, glyceryl-tri (acetylricinoleate), and triethylene glycol diacetate.

Examples of the epoxy plasticizer include epoxidized vegetable oil plasticizers and epoxidized fatty acid alkyl esters.
Examples of the epoxidized vegetable oil-based plasticizer include epoxidized soybean oil and epoxidized linseed oil.
Examples of the epoxidized fatty acid alkyl ester include epoxy methyl stearate, butyl epoxy stearate, 2-ethylhexyl epoxy stearate and the like.
In addition, epoxidized polybutadiene, tris (epoxypropyl) isocyanurate, 3- (2-xenoxy) -1,2-epoxypropane, bisphenol A diglycidyl ether, vinyldicyclohexene diepoxide, 2,2-bis (4-hydroxy) And a polycondensate of phenyl) propane and epichlorohydrin.

  Examples of the polymer plasticizer include a liquid polyurethane resin, a polyester plasticizer obtained from a dicarboxylic acid and a glycol; an etherified product or an esterified product of a polyalkylene glycol such as polyethylene glycol or polypropylene glycol; a polyvalent saccharide such as sucrose. Polyether plasticizers such as saccharide-based polyethers obtained by addition polymerization of alkylene oxides such as ethylene oxide and propylene oxide to alcohol and then etherification or esterification; polystyrene plastics such as poly-α-methylstyrene Agent; poly (meth) acrylate other than the methacrylic polymer (A).

Among the above poly (meth) acrylates, a poly (meth) acrylate having a Mw of 1,000 to 7,000 and a glass transition temperature of −30 ° C. or lower maintains durability such as weather resistance of the cured product. Is particularly preferable. The poly (meth) acrylate may have a carboxyl group, a hydroxyl group, a hydrolyzable silyl group, an epoxy group, or the like. In addition, as the poly (meth) acrylate, “ARUFON UP1000”, “ARUFON UP1010”, “ARUFON UP1020”, “ARUFON UP1060”, “ARUFON UP1080”, “ARUFON UP1110”, “ARUFON UH2000” manufactured by Toagosei Co., Ltd. , “ARUFON UH2130” (the trade name, “ARUFON” is a trademark of Toagosei Co., Ltd.), and the like.
The plasticizer can also be blended during the production of the methacrylic copolymer (A).

  When the curable composition of the present invention contains a plasticizer, the upper limit of the content is preferably 150 parts by mass with respect to 100 parts by mass of all the polymers including the methacrylic copolymer (A). More preferably, it is 100 mass parts, More preferably, it is 50 mass parts.

  Examples of the tackifier include coumarone-indene resin; coumarone resin obtained by mixing naphthene resin, phenol resin, rosin and the like with coumarone resin; p-tert-butylphenol-acetylene resin; phenol-formaldehyde resin; xylene-phenol Resin; Xylene resin; Terpene resin; Terpene resin such as terpene-phenol resin; Synthetic polyterpene resin; Aromatic hydrocarbon resin; Aliphatic hydrocarbon resin; Aliphatic cyclic hydrocarbon resin; Hydrogenated hydrocarbon resin; Rosin pentaerythritol ester; rosin glycerol ester; hydrogenated rosin; hydrogenated wood resin; hydrogenated rosin methyl ester; hydrogenated rosin triethylene glycol ester; hydrogenated rosin pentaerythritol Ester; polymerized rosin; resin zinc; glycerol esters of polymerized rosin hardened rosin; low molecular weight polystyrene, and the like. These may be used alone or in combination of two or more.

  When the curable composition of the present invention contains a tackifier, the upper limit of the content is preferably 100 parts by mass with respect to 100 parts by mass of all the polymers including the methacrylic copolymer (A). More preferably, it is 50 mass parts, More preferably, it is 30 mass parts.

  The dehydrating agent is used to remove moisture during storage of the curable composition and maintain storage stability. For example, vinyltrimethoxysilane, vinyltriethoxysilane, methyltrimethoxysilane , Phenyltrimethoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, dimethyldimethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, phenylmethyldiethoxysilane, dimethyldiethoxysilane, γ-aminopropyltrimethoxysilane, γ- Aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltriethoxysilane, N- (Β- Aminoethyl) -γ-aminopropylmethyldimethoxysilane, 1,3-diaminoisopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxy Examples thereof include silane and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. These can be used alone or in combination of two or more.

  When the curable composition of the present invention contains a dehydrating agent, the content is preferably 0.01 to 20 mass with respect to 100 parts by mass of all the polymers including the methacrylic copolymer (A). Part, more preferably 0.1 to 10 parts by mass.

Examples of the organic solvent include aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, halogen-substituted compounds in which one or more hydrogen atoms in these hydrocarbons are substituted with halogen atoms, cyclic ethers, acetate esters, Examples include ketone compounds, orthocarboxylic acid esters, and alcohols. These organic solvents may be used alone or in combination of two or more.
Examples of the aromatic hydrocarbon include benzene, toluene, xylene and the like.
Examples of the cyclic ether include tetrahydrofuran and dioxane.
Examples of the acetate ester include ethyl acetate, methyl acetate, and butyl acetate.
Examples of the ketone compound include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.
Examples of the orthocarboxylic acid ester include methyl orthoformate and methyl orthoacetate.
Examples of the alcohol include methanol, ethanol, isopropanol and the like.

  The viscosity of the curable composition of the present invention is preferably 5 to 400 Pa · s, more preferably 10 to 350 Pa · s when measured at a temperature of 25 ° C. using an E-type viscometer. When the viscosity of the composition is in the above range, the workability when handling the composition is excellent.

Next, the manufacturing method of the methacrylic copolymer (A) contained in the curable composition of this invention is demonstrated.
The methacrylic copolymer (A) can be obtained by applying a conventionally known production method so as to have the specific configuration. In the curable composition of this invention, it obtains with the manufacturing method provided with the polymerization method of the following (x) or (y) rather than the composition containing the methacrylic copolymer obtained by the manufacturing method provided with a batch polymerization method. The composition containing the obtained methacrylic copolymer is more stable in terms of physical properties. In the former manufacturing method, problems such as contamination of impurities and coloring may be caused. In order to obtain the above-mentioned specific configuration, more processes are required, and the latter manufacturing method is more economical.
(X) butyl methacrylate, at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate, a polymerizable unsaturated compound having a hydrolyzable silyl group, and a polymerization initiator, A method comprising a polymerization step of polymerizing a monomer mixture (hereinafter referred to as “monomer mixture (t1)”) at a temperature of 150 ° C. to 350 ° C. while continuously supplying the monomer mixture to the reaction system.
(Y) a monomer component containing butyl methacrylate and at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate (hereinafter referred to as “monomer component (t2)”) .) Comprising a polymerization step of living radical polymerization.

  In the method (x), the monomer component contained in the monomer mixture (t1) is at least one selected from butyl methacrylate, methyl acrylate, methyl methacrylate, ethyl acrylate, and ethyl methacrylate. And a polymerizable unsaturated compound having a hydrolyzable silyl group, and other polymerizable unsaturated compounds used as necessary. The ratio of these compounds is selected in consideration of the polymerization conversion rate and the like so that the obtained methacrylic copolymer (A) has the above-mentioned specific configuration.

The polymerization initiator contained in the monomer mixture (t1) is not particularly limited, and a conventionally known polymerization initiator that can generate a radical at a predetermined polymerization temperature can be used. .
Examples of the polymerization initiator include organic peroxides, azo compounds, inorganic peroxides, and redox polymerization initiators.

  Examples of the organic peroxide include tert-amyl-tert-butyl peroxide, tert-butyl-tert-hexyl peroxide, tert-amyl-tert-hexyl peroxide, di (tert-butyl) peroxide, di (tert). -Amyl) peroxide, di (tert-hexyl) peroxide, cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, 1,1-bis (tert-butylperoxy) -3, 3,5-trimethylcyclohexane, 1,1-bis (tert-butylperoxy) cyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, cumene hydroperoxide, 2,5-di Tilhexane-2,5-dihydroperoxide, 1,3-bis (tert-butylperoxy) -m-isopropyl) benzene, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, Diisopropylbenzene peroxide, tert-butylcumyl peroxide, decanoyl peroxide, lauroyl peroxide, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, bis (tert-butylcyclohexyl) peroxydicarbonate, tert-butylperoxide Examples thereof include oxybenzoate and 2,5-dimethyl-2,5-di (benzoylperoxy) hexane.

  Examples of the azo compound include 2,2′-azobis (isobutyronitrile), 1,1-azobis (cyclohexane-1-carbonitrile), azocumene, and 2,2′-azobis (2-methylbutyronitrile). 2,2′-azobisdimethylvaleronitrile, 4,4′-azobis (4-cyanovaleric acid), 2- (tert-butylazo) -2-cyanopropane, 2,2′-azobis (2,4,4) 4-trimethylpentane), 2,2′-azobis (2-methylpropane), dimethyl 2,2′-azobis (2-methylpropionate) and the like.

Examples of the inorganic peroxide include potassium persulfate, sodium persulfate, and ammonium persulfate.
Redox polymerization initiators include sodium sulfite, sodium thiosulfate, sodium formaldehyde sulfoxylate, ascorbic acid, ferrous sulfate, etc. as reducing agents, potassium peroxodisulfate, hydrogen peroxide, tert-butyl hydroper What used an oxide etc. as an oxidizing agent can be used.

As the polymerization initiator, organic peroxides and azo compounds, in which initiator radicals hardly cause extraction of hydrogen atoms, are preferable, and peroxides are particularly preferable. Further, as the peroxide, di (tert-butyl) peroxide, di (tert-amyl) peroxide and di (tert-hexyl) peroxide are more preferable, and di (tert-amyl) peroxide and di ( tert-Hexyl) peroxide is particularly preferred. By using a peroxide as the polymerization initiator, it is difficult for hydrogen atoms to be extracted from the copolymer by the generated initiator radicals, and it is possible to suppress branching and gelation of the resulting copolymer. it can.
The usage-amount of the said polymerization initiator is 0.01-10 mass parts normally with respect to 100 mass parts of monomer components contained in a monomer mixture (t1).

The monomer mixture (t1) may contain an organic solvent.
Examples of the organic solvent include linear or branched aliphatic hydrocarbons; alicyclic hydrocarbons; aromatic hydrocarbons such as benzene, toluene and xylene; one or more hydrogen atoms in these hydrocarbons are halogen atoms Halogen-substituted compounds substituted with: cyclic ethers such as tetrahydrofuran and dioxane; acetic acid esters such as ethyl acetate, methyl acetate and butyl acetate; ketone compounds such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; methyl orthoformate and orthoacetic acid Examples thereof include orthocarboxylic acid esters such as methyl; alcohols such as methanol, ethanol and isopropanol. These organic solvents may be used alone or in combination of two or more.
In the present invention, particularly preferred organic solvents are methyl orthoformate and methyl orthoacetate, which are excellent in solubility of the resulting copolymer and can remove moisture. When these compounds are used, a polymer containing a moisture-curable silyl group is produced. If the water content in the polymerization system is not reduced as much as possible, a crosslinking reaction occurs during the polymerization, resulting in a polymer having a wide molecular weight distribution. is there. When methyl orthoformate and methyl orthoacetate are used, stable polymerization can be performed without causing a crosslinking reaction of silyl groups. Further, by reducing the water in the reaction system as much as possible, the crosslinking reaction can be suppressed during the polymerization of the monomer component, and a copolymer having a narrow molecular weight distribution can be obtained.

  The usage-amount of the said organic solvent is 0-100 mass parts normally with respect to 100 mass parts of monomer components contained in a monomer mixture (t1).

In the polymerization step in the method (x), the monomer mixture (t1) is preferably supplied at 150 ° C. to 350 ° C., more preferably 160 ° C. to 250 ° C., and still more preferably 170 while continuously supplying the monomer mixture to the reaction system. Polymerization is performed at a temperature of from 220C to 220C. When the polymerization reaction is stabilized, an amount of the reaction liquid corresponding to the supply amount of the monomer mixture (t1) is extracted and collected.
The polymerization of the monomer mixture (t1) may be performed under pressure, atmospheric pressure, or reduced pressure. In the present invention, it is preferable to polymerize under pressure. When polymerization is carried out under pressure, a pressurizable reactor is used, and the pressure depends on the reaction temperature and the boiling point of the monomer mixture and solvent used, but does not affect the reaction. Any pressure may be used as long as the reaction temperature can be maintained.

In the polymerization step, the monomer mixture (t1) is continuously supplied to the reaction system and is usually polymerized with stirring.
The polymerization time (retention time) of the monomer mixture (t1) is preferably 1 to 60 minutes, more preferably 2 to 40 minutes, and further preferably 5 to 30 minutes. When the polymerization time (residence time) is too short, the polymerization conversion rate of the monomer tends to be low. On the other hand, if the polymerization time (residence time) is too long, the polymerization conversion rate of the monomer increases, but the productivity tends to decrease.

In the method (x), after the polymerization step, the methacrylic copolymer (A) can be recovered from the reaction solution by a volatile component removal step such as an organic solvent by a known means. .
As an apparatus used in this volatile component removal process, a falling evaporator, a thin film evaporator, an extruder dryer, etc. are mentioned, for example. The heating temperature of the reaction solution is preferably 300 ° C. or lower, more preferably 270 ° C. or lower, particularly preferably 250 ° C. or lower. If the heating temperature is too high, the resulting methacrylic copolymer (A) may be colored or a low molecular weight component may be generated by decomposition. Moreover, it is preferable to perform removal of a volatile component under reduced pressure, for example, can be 50 kPa or less. A more preferable pressure is 30 kPa or less, and particularly preferably 10 kPa or less. By setting it as the said pressure, a volatile component can fully be removed.

  On the other hand, in the above method (y), the monomer component (t2) includes butyl methacrylate, at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate, and ethyl methacrylate, and as necessary. And other polymerizable unsaturated compounds used. The ratio of these compounds, that is, butyl methacrylate, and at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate is the same as in the case of method (x). The system copolymer (A) is selected so as to have the specific configuration. In addition, as other polymerizable unsaturated compounds, polymerizable unsaturated compounds having a hydrolyzable silyl group, and polymerizable unsaturated compounds (the compounds exemplified above) that form the structural unit (a3). Etc.

  In the polymerization step in the method (y), the monomer component (t2) is subjected to living radical polymerization, and a living radical polymerization initiator is used. In this method (y), preferably, the polymerization is continued while the hydrolyzable silyl group is present at one end of the polymer formed by the polymerization of the monomer component (t2). If necessary, a polymerizable unsaturated compound having a hydrolyzable silyl group is added to the final stage of the polymerization, and the hydrolyzable silyl group derived from this monomer is added at or near the other end. Can be arranged.

（式中、Ｒ^８は水素原子又は炭素数１〜２のアルキル基であり、Ｒ^９は炭素数１〜２のアルキル基又はニトリル基であり、Ｒ^１０は−（ＣＨ_２）_ｓ−（ｓは０、１又は２である。）であり、Ｒ^１１は互いに独立して炭素数１〜４のアルキル基である。） As described above, the method for producing a polymer using living radical polymerization includes a method using a nitroxide radical, an atom transfer radical polymerization (ATRP) method, a method using an initiator using tellurium metal, and a reversible addition. A cleavage chain transfer polymerization (RAFT) method or the like can be applied.
In the production method of the methacrylic acid copolymer (A) according to the present invention, preferably, as a living radical polymerization initiator, a nitroxide compound represented by the following general formula (4) is used as a compound having a hydrolyzable silyl group. , A compound having a hydrolyzable silyl group and an epoxy bond, respectively, in combination with the monomer component (t2). In this reaction system, stable nitroxy free radicals are generated, which allows polymerization growth while the terminal is in an inactive state and the active state in an equilibrium state, and the polydispersity is adjusted. The produced polymer is efficiently produced. In addition, since the compound which has a hydrolyzable silyl group and an epoxy bond is used, since the epoxy part in this compound and the carboxyl group in the nitroxide compound represented by the following general formula (4) undergo an addition reaction, A polymer in which an inactive hydrolyzable silyl group remains can be produced.

(In the formula, R ⁸ is a hydrogen atom or an alkyl group having 1 to 2 carbon atoms, R ⁹ is an alkyl group having 1 to 2 carbon atoms or a nitrile group, and R ¹⁰ is — (CH ₂ ) _s — (s Is 0, 1 or 2.) and R ¹¹ is independently an alkyl group having 1 to 4 carbon atoms.

  The usage-amount of the nitroxide compound represented by the said General formula (4) is 2-20 mass parts normally with respect to 100 mass parts of monomer components (t2).

  Examples of the compound having a hydrolyzable silyl group and an epoxy bond include 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, (2-glycidoxyethyl) methyldimethoxysilane, 3 -Glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3 , 4-epoxycyclohexyl) ethyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl (methyl) dimethoxysilane, and the like.

  The amount of the compound having a hydrolyzable silyl group and an epoxy bond is preferably 0.8 to 2.0 mol, more preferably 1 with respect to 1 mol of the nitroxide compound represented by the general formula (4). 0.0 to 1.7 mol, particularly preferably 1.1 to 1.5 mol. By setting it as the said usage-amount, the number of the hydrolysable silyl groups contained in a methacrylic copolymer (A) can be efficiently made into 0.5-4 pieces. In addition, when there are too few usage-amounts of the compound which has the said hydrolysable silyl group and an epoxy bond, the quantity of the hydrolysable silyl group introduce | transduced into the terminal will reduce, and the tensile physical property of hardened | cured material may fall. On the other hand, if the amount used is too large, the unreacted crosslinkable silyl group-containing glycidyl compound remains in the composition, and the crosslink density is excessively lowered during curing, which may reduce the mechanical properties of the cured product.

  For the living radical polymerization in the above method (y), a batch process, a semi-batch process, a tubular continuous polymerization process, a continuous stirred tank type process (CSTR), or the like can be applied. Preferred methods are batch processes, semi-batch processes and tubular continuous polymerization processes, particularly preferably batch processes. The polymerization format may be solution polymerization using an organic solvent, bulk polymerization without using an organic solvent, or the like.

  A preferred polymerization step in the method (y) is a step of polymerizing the monomer component (t2) in the presence of the nitroxide compound (living radical polymerization initiator) and a compound having a hydrolyzable silyl group and an epoxy bond. . When the methacrylic copolymer (A) is produced using the nitroxide compound (living radical polymerization initiator) and the compound having a hydrolyzable silyl group and an epoxy bond, a catalyst is used to increase the production efficiency. Is preferably used. The catalyst is not particularly limited as long as it promotes the reaction between the glycidyl group and the carboxyl group and does not affect the hydrolyzable silyl group, but is preferably a quaternary ammonium salt.

  Examples of the quaternary ammonium salt include tetrabutylammonium bromide, benzyltrimethylammonium chloride, benzyltriethylammonium chloride, tributylammonium bromide and the like.

  The amount of the catalyst used is preferably from 0.1 to 2 parts by mass, more preferably from 0.2 to 1 part by mass, particularly from 100 parts by mass of the monomer component (t2), from the viewpoint of production efficiency. Preferably it is 0.3-0.5 mass part. In addition, when there is too little usage-amount of the said catalyst, the said effect may not fully be acquired. On the other hand, when there is too much usage-amount of a catalyst, when it is set as a curable composition, precipitation may be formed.

In the preferred polymerization step in the method (y), the polymerization of the monomer component (t2) is usually performed in an organic solvent.
Examples of the organic solvent include linear or branched aliphatic hydrocarbons; alicyclic hydrocarbons; aromatic hydrocarbons such as benzene, toluene and xylene; one or more hydrogen atoms in these hydrocarbons are halogen atoms Halogen-substituted compounds substituted with: cyclic ethers such as tetrahydrofuran and dioxane; acetic acid esters such as ethyl acetate, methyl acetate and butyl acetate; ketone compounds such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; methyl orthoformate and orthoacetic acid Examples thereof include orthocarboxylic acid esters such as methyl; alcohols such as methanol, ethanol and isopropanol. These organic solvents may be used alone or in combination of two or more.
In the present invention, particularly preferred organic solvents are methyl orthoformate and methyl orthoacetate, which are excellent in solubility of the resulting copolymer and can remove moisture. When these compounds are used, a polymer containing a moisture-curable silyl group is produced. If the water content in the polymerization system is not reduced as much as possible, a crosslinking reaction occurs during the polymerization, resulting in a polymer having a wide molecular weight distribution. is there. When methyl orthoformate and methyl orthoacetate are used, stable polymerization can be performed without causing a crosslinking reaction of silyl groups. Further, by reducing the water in the reaction system as much as possible, the crosslinking reaction can be suppressed during the polymerization of the monomer component, and a copolymer having a narrow molecular weight distribution can be obtained.

  The amount of the organic solvent used is preferably 0 to 200 parts by weight, more preferably 0 to 100 parts by weight, still more preferably 5 to 35 parts by weight, particularly preferably 100 parts by weight of the monomer component (t2). Is 10 to 20 parts by mass. If the amount of the organic solvent used is too large, a chain transfer reaction caused by the organic solvent may occur, and the polymerization control such as molecular weight control, molecular weight distribution control, and terminal living property may be lowered. On the other hand, if the amount of the organic solvent used is too small, the hydrolyzable silyl group crosslinking reaction may proceed.

  In the polymerization step in the above method (y), the polymerization temperature of the monomer component (t2) accommodated in the reactor is preferably 90 ° C to 130 ° C, more preferably 95 ° C to 120 ° C, still more preferably 100 ° C to Polymerize at 115 ° C. When the polymerization temperature is too low, the polymerization rate tends to decrease. On the other hand, if the polymerization temperature is too high, the nitroxide radical cannot cap the growing radical, and the recombination reaction between the growing radicals, the disproportionation reaction, the hydrogen atom abstraction reaction from the polymer main chain, and the back-biting reaction. May cause a β-decomposition reaction and lose the living polymerizability, making it impossible to control radical polymerization.

  The polymerization of the monomer component (t2) may be performed under atmospheric pressure, increased pressure, or reduced pressure depending on the monomer used, the boiling point of the organic solvent, and the reaction temperature, and a polymerization method is appropriately selected.

  In the polymerization step in the above method (y), the polymerization conversion rate of the monomer component (t2) is preferably 70 to 99%, more preferably 75 to 95%, and particularly preferably 80 to 90%. . The polymerization time depends on the type of monomer, polymerization temperature and the like, but is usually 3 to 15 hours, preferably 5 to 10 hours.

  In the polymerization step, as described above, the monomer component (t2) is composed of butyl methacrylate and at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate, and ethyl methacrylate. And may be used as butyl methacrylate, at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate, and a polymerizable unsaturated compound having a hydrolyzable silyl group. It may be used as a thing. In the latter case, a first monomer composed of butyl methacrylate and at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate is polymerized, and the polymerization conversion rate is preferably When 70 to 99%, more preferably 75 to 95%, still more preferably 80 to 90%, a polymerizable unsaturated compound having a hydrolyzable silyl group is added to the reaction system, and polymerization is continued. If the polymerization conversion rate is within the above range, the hydrolyzable silyl group can be efficiently introduced at or near the growth end. When a polymerizable unsaturated compound having a hydrolyzable silyl group is added when the polymerization conversion rate is less than 70%, it becomes close to the α-terminal silyl group, and excellent tensile properties may not be obtained. On the other hand, when a polymerizable unsaturated compound having a hydrolyzable silyl group is added at a place where the polymerization conversion rate is too high, the copolymerization rate is lowered and may not be introduced into the polymer chain.

In the method (y), after the polymerization step, the methacrylic copolymer (A) can be recovered from the reaction solution by a volatile component removal step such as an organic solvent by a known means. .
As an apparatus used in this volatile component removal process, a falling evaporator, a thin film evaporator, an extruder dryer, etc. are mentioned, for example. The heating temperature of the reaction solution is preferably 200 ° C. or lower, more preferably 150 ° C. or lower, and particularly preferably 130 ° C. or lower. By setting the heating temperature as described above, the living radical polymerization terminal is not dissociated, and generation of a low molecular weight component due to decomposition of the copolymer is suppressed, which is preferable. When the heating temperature is too high, the living radical polymerization terminal is dissociated, the polymer chain is partially decomposed, and a low molecular weight component is generated. Further, the resulting methacrylic copolymer (A) is colored. There is a case. Moreover, it is preferable to perform removal of a volatile component under reduced pressure, for example, can be 10 kPa or less. A more preferable pressure is 5 kPa or less, and particularly preferably 1 kPa or less. By setting it as the said pressure, a volatile component can fully be removed.

  Since the curable composition of the present invention contains a specific methacrylic copolymer and a curing accelerator, it is excellent in moisture curability. This composition can be a one-component type or a two-component type, and is particularly suitable as a one-component type composition. For example, when a composition is used to form a coating film or the like and then exposed to the atmosphere, it is cured while forming a three-dimensional network structure by the action of moisture, and a cured product having a rubber-like elasticity (solid film ) Is obtained. Moreover, this hardened | cured material is excellent in adhesiveness with respect to adherends, such as resin, glass, porcelain, wood, and a metal, and is excellent in sclerosis | hardenability, transparency, rubber physical property, storage stability, deep part curability, and quick curability. Therefore, the curable composition of the present invention is an adhesive, a sealing agent, a paint, and a coating agent for civil engineering, architectural use, vehicle use, electrical product use, and electronic component use in order to make use of such properties of the cured product. In addition to sealing agents, it is useful as a primer agent for civil engineering or architectural resin coating, wood coating, and the like.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples as long as the gist of the present invention is not exceeded. In the following, “part” and “%” are based on mass unless otherwise specified.

1. Physical property measurement method and evaluation method The physical property measurement method and evaluation method according to the curable composition and the polymer component contained therein are as follows.
1-1. Weight average molecular weight (Mw) and number average molecular weight (Mn) of methacrylic copolymer
Using a gel permeation chromatograph (model name “HLC-8120”, manufactured by Tosoh Corporation), Mw and Mn were measured under the following conditions, and converted to standard polystyrene.
<Measurement conditions>
Column: 4 TSKgel SuperMultipore HZ-M (manufactured by Tosoh Corporation)
Column temperature: 40 ° C
Eluent: Tetrahydrofuran Detector: RI
1-2. The average number of hydrolyzable silyl groups contained in the methacrylic copolymer The number (average number) of alkoxysilyl groups which are hydrolyzable silyl groups is the spectrum obtained by ¹ H-NMR measurement of the copolymer. It calculated from the integral value by the following formula.
f (Si) = {alkoxysilyl group concentration in the polymer [mol / kg] / (1,000 / number average molecular weight)}
1-3. Viscosity of the composition Using an E-type viscometer, the viscosity was measured at a temperature of 25 ° C. ± 0.5 ° C.

1-4. Tensile properties The curable composition was poured into a mold and allowed to stand for 1 week under conditions of a temperature of 23 ° C. and a relative humidity of 50% to obtain a cured sheet having a thickness of 2 mm. Thereafter, this cured sheet was processed to produce a tensile test dumbbell (JIS K 6251-3 type).
Next, using a tensile tester “Tensilon 200” (model name) manufactured by Toyo Seiki Seisakusho Co., Ltd. under the conditions of a temperature of 23 ° C., a humidity of 50% RH and a tensile speed of 5 cm / min, “50% M”, unit: N / mm ² ), strength at break (hereinafter referred to as “Ts”, unit: N / mm ² ) and elongation (hereinafter referred to as “El”, unit:%). It was measured.

1-5. Adhesiveness For evaluation of adhesiveness, two polycarbonate plates (thickness 2 mm, width 25 mm, length 50 mm) were used. The curable composition was applied to each surface of one side of the two polycarbonate plates from the plate end to 12.5 mm with a bar coater no. 50 (coating thickness 50 μm). Then, it was left for 3 minutes, the coating film surfaces were brought into contact with each other, the polycarbonate plates were bonded to each other (area 25 mm × 12.5 mm), and a test specimen for evaluation was produced.
The obtained test body was clamped and crimped, and cured for 1 day under the conditions of a temperature of 23 ° C. and a humidity of 50% RH, and further cured for 6 days under the conditions of a temperature of 23 ° C. and a humidity of 50% RH (total 7 days). ). The test specimen was subjected to a tensile test using a tensile tester “Tensilon 200” (model name) manufactured by Toyo Seiki Seisakusho. That is, the shear bond strength (unit: N / mm ² ) was measured under conditions of a temperature of 23 ° C., a humidity of 50% RH, and a tensile speed of 5 cm / min. At that time, the shear plane was observed and the cohesive failure rate (unit:%) was measured.

1-6. In order to evaluate the compatibility between a methacrylic copolymer and an oxyalkylene polymer having a hydrolyzable silyl group, an oxyalkylene polymer having a hydrolyzable silyl group is used as a silyl functional group manufactured by Kaneka Corporation. Terminal polypropylene oxide “SAT-200” (trade name) was used. The amount used is 30 parts and 70 parts for the methacrylic copolymer and the oxyalkylene polymer, respectively. First, both were mixed using a planetary mixer for 1 hour under the conditions of a temperature of 60 ° C. and a pressure of 10 Torr, and then left to stand. The appearance of the mixture was visually observed and judged according to the following criteria.
“Transparent”: The mixture was transparent.
“White turbidity”: Turbidity was observed in the mixture.
“Insoluble”: Polymer components were separated.

2. Production of Methacrylic Copolymer (A), etc. Synthesis Example 1 (Synthesis of Copolymer (A-1))
The temperature of the pressurized stirred tank reactor equipped with an oil jacket was kept at 171 ° C. Next, 30.0 parts of n-butyl methacrylate (hereinafter referred to as “nBMA”) and 55.0 parts of methyl methacrylate previously contained in the raw material tank while keeping the pressure in the reactor constant. (Hereinafter referred to as “MMA”), 15.0 parts of 3-methacryloxypropyltrimethoxysilane (hereinafter referred to as “MTMS”), 3.0 parts of methyl ethyl ketone, and 10.0 parts of isopropyl alcohol. A monomer mixture consisting of 2.0 parts of methyl orthoacetate (hereinafter referred to as “MOA”) and 2.5 parts of di-tert-hexyl peroxide (polymerization initiator). Polymerization was carried out at the same time with stirring while starting the supply to the reactor under the conditions of / min. Immediately after the start of the reaction, the temperature of the reaction system once decreased and a temperature increase due to the heat of polymerization was observed, but the reaction system was maintained at a temperature of 171 ° C. and a pressure of 0.7 MPa by controlling the oil jacket. .
Thereafter, an amount of the reaction liquid corresponding to the supply amount of the monomer mixture is added to the reactor while keeping the residence time substantially constant (about 12 minutes) so that a certain amount of the reaction liquid stays in the reactor. It was continuously extracted from the discharge port arranged in and collected. In addition, after the temperature was stabilized from the start of the supply of the monomer mixture and reacted for 36 minutes, this was regarded as the time when the polymerization was stabilized, and this was designated as “containing a methacrylic copolymer used in the curable composition”. It was set as the collection start point of the “reaction solution”. Then, the polymerization proceeded under the above conditions, and 1.2 kg of “reaction liquid containing a methacrylic copolymer used in the curable composition” was recovered.
Next, the “reaction liquid containing a methacrylic copolymer used in the curable composition” is introduced into a thin film evaporator to remove volatile components such as unreacted monomers, and the methacrylic copolymer (A -1) was obtained. The conversion rate of the monomer was 65% for nBMA and 65% for MMA.
Mn of the methacrylic copolymer (A-1) was 3,000, Mw was 6,500, and Mw / Mn was 2.2 (see Table 1). Further, the number f (Si) of alkoxysilyl groups per polymer chain of the polymer was 1.8.

  In Table 1, the numerical value in the column of “monomer (part)” is the amount used during polymerization. When there are numerical values in the upper and lower stages, the upper numerical value is the amount used, and the lower parenthesis is the methacrylic copolymer according to the present invention calculated based on the conversion rate of the monomer used during the polymerization ( It is the ratio of the structural units (a1) and (a2) constituting A). In addition, in the following synthesis examples, when the monomer used does not include a compound that forms both the structural units (a1) and (a2), only the amount used is shown.

Synthesis Examples 2 to 13 (Synthesis of copolymers (A-2) to (A-13))
Copolymers (A-2) to (A-13) were obtained in the same manner as in Synthesis Example 1 except that the monomers and polymerization initiators were used for polymerization with the types and amounts used in Table 1. (See Table 1).
In Table 1, “iBMA”, “nBA”, “MA”, “EA” and “2EHA” are isobutyl methacrylate, n-butyl acrylate, methyl acrylate, ethyl acrylate and acrylic acid 2 respectively. -Ethylhexyl.

The conversion rate of the monomer in Synthesis Example 2 was 66% for nBMA and 64% for MMA.
Regarding the conversion rate of the monomer in Synthesis Example 3, iBMA was 75% and EA was 80%.
Regarding the conversion rate of the monomer in Synthesis Example 4, iBMA was 66% and EA was 82%.
The conversion rate of the monomer in Synthesis Example 5 was 66% for iBMA and 85% for MA.
As for the conversion rate of the monomer in Synthesis Example 6, nBMA was 66% and MMA was 64%.
Regarding the conversion rate of the monomer in Synthesis Example 7, nBMA was 75%, BA was 81%, and MMA was 76%.
Regarding the conversion rate of the monomer in Synthesis Example 8, nBMA was 64% and MMA was 64%.
Regarding the conversion rate of the monomer in Synthesis Example 9, nBMA was 65% and MMA was 67%.
Regarding the conversion rate of the monomer in Synthesis Example 10, MA was 90% and 2EHA was 90%.
As for the conversion rate of the monomer in Synthesis Example 11, EA was 90% and 2EHA was 91%.
As for the conversion rate of the monomer in Synthesis Example 12, BA was 83% and MMA was 77%.
As for the conversion rate of the monomer in Synthesis Example 13, iBMA was 80% and MA was 91%.

その後、反応液を冷却して、反応器から抜き出した。そして、反応液を、蒸発器に導入して、減圧度０．３ｋＰａ及び温度９０℃の条件下、５時間かけて減圧乾燥し、メタクリル系共重合体（Ａ−１４）を得た。尚、上記リビング重合開始剤のカルボキシル基の反応率は１００％であった。
メタクリル系共重合体（Ａ−１４）のＭｎは４，０００、Ｍｗは５，２００、Ｍｗ／Ｍｎは１．３であった（表２参照）。また、この重合体の高分子鎖１本あたりのアルコキシシリル基の数ｆ（Ｓｉ）は２．２であった。 Synthesis Example 14 (Synthesis of copolymer (A-14))
In a pressurized stirred tank reactor equipped with an oil jacket, 55.0 parts of nBMA, 37.6 parts of MA, 9.7 parts of a living polymerization initiator shown below, 10.0 parts of MOA, 3-glycidoxy A mixed solution consisting of 5.9 parts of propyltrimethoxysilane (trade name “KBM-403”, manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.3 part of tetra-n-butylammonium bromide (catalyst) was charged. Next, after the mixed solution was sufficiently deaerated by bubbling with nitrogen gas, the temperature of the reaction system was set to 110 ° C. by controlling the oil jacket, and polymerization was started with stirring. The temperature of the reaction system was maintained at 110 ° C., and after 3 hours, 7.4 parts of MTMS was added. And it was made to react for 1.5 hours as it is. At this time, the polymerization rate of BMA was 97%, the polymerization rate of MA was 90%, and the polymerization rate of MTMS was 95%.

Thereafter, the reaction solution was cooled and extracted from the reactor. And the reaction liquid was introduce | transduced into the evaporator, and it dried under reduced pressure over 5 hours on the conditions of 0.3 kPa and 90 degreeC of pressure reduction, and obtained the methacrylic copolymer (A-14). The reaction rate of the carboxyl group of the living polymerization initiator was 100%.
Mn of the methacrylic copolymer (A-14) was 4,000, Mw was 5,200, and Mw / Mn was 1.3 (see Table 2). Further, the number f (Si) of alkoxysilyl groups per polymer chain of this polymer was 2.2.

  In Table 2, the numerical value in the column of “monomer (part)” is the amount used at the time of polymerization, and the numerical value in parentheses is the polymerization conversion rate. When there are numerical values in the upper and lower stages, the upper numerical value is the amount used, and the lower parenthesized values are the proportions of the structural units (a1) and (a2) constituting the methacrylic copolymer (A) according to the present invention. It is.

Synthesis Examples 15 to 18 (Synthesis of copolymers (A-15) to (A-18))
Copolymers (A-15) to (A-18) were obtained in the same manner as in Synthesis Example 1 except that the monomers and polymerization initiators were used for polymerization with the types and amounts used in Table 2. (See Table 2).

3. Production and Evaluation of Curable Composition Examples 1-12 and Comparative Examples 1-7
Using the copolymer (A) obtained in the above synthesis example and the following components at a ratio shown in Tables 3 and 4, using a planetary mixer, the temperature is 60 ° C. and the pressure is 10 Torr. Mixing for a time, a curable composition was obtained. Various evaluations were performed. The results are shown in Tables 3 and 4.
3-1. Curing accelerator (B)
Dibutyltin diacetylacetonate (trade name “U220H”, manufactured by Nitto Kasei Co., Ltd.) was used.
3-2. Oxyalkylene polymer having hydrolyzable silyl group (C)
Polypropylene oxide having a dimethoxysilyl group (trade name “SAT-200”, manufactured by Kaneka Corporation) was used. Mn is 4,300.
3-3. Light calcium carbonate (trade name “Calfine 200M”, manufactured by Maruo Calcium Co., Ltd.) as filler (F-1), and heavy calcium carbonate (trade name “Super SS”, Maruo Calcium Co., Ltd.) as (F-2). Made).
3-4. Dehydrating agent Vinyltrimethoxysilane (trade name “SZ6300”, manufactured by Toray Dow Corning Silicone) was used.
3-5. Tackifier 3- (2-aminoethyl) aminopropyltrimethoxysilane (trade name “SH-6020”, manufactured by Toray Dow Corning) was used.

When exposed to the atmosphere, the curable composition of the present invention forms a three-dimensional network structure by the action of moisture, cures, and changes to a solid having rubbery elasticity. The curable composition of the present invention is a resin for civil engineering or construction, including adhesives, sealing agents, paints, coating agents and sealants for civil engineering, construction, vehicles, electrical products, electronic parts, etc. It is useful as a primer agent for coating and woodworking.
The use method as an adhesive is a one-part adhesive, a two-part adhesive, a contact adhesive that adheres after an open time, a pressure-sensitive adhesive, such as a resin, glass, porcelain, wood, metal, or the like directly or It is a method of applying, spraying, etc. with the help of a primer layer.
For example, when an electronic component such as a semiconductor element is fixed at a predetermined position on a substrate, the semiconductor element is sealed by, for example, potting a curable composition on the electronic component. How to do it.

Claims (6)

In the curable composition containing (A) a methacrylic copolymer , (B) a curing accelerator, and (C) an oxyalkylene polymer having a hydrolyzable silyl group ,
The methacrylic copolymer (A) includes a structural unit (a1) derived from butyl methacrylate, a structural unit derived from methyl acrylate, a structural unit derived from methyl methacrylate, and a structural unit derived from ethyl acrylate. And having at least one structural unit (a2) selected from structural units derived from ethyl methacrylate, and a hydrolyzable silyl group,
The content ratios of the structural unit (a1) and the structural unit (a2) are 35 to 90% by mass and 10 to 65% by mass, respectively, when the total of both is 100% by mass, and
The methacrylic copolymer (A) has a number average molecular weight of 2,000 to 10,000. The content ratio of the methacrylic copolymer (A) and the oxyalkylene polymer (C) is 20 to 90% by mass and 10 to 80% by mass, respectively, when the total of both is 100% by mass. The curable composition according to claim 1 . The curable composition according to claim 1 or 2, wherein the content of the curing accelerator (B) is 0.01 to 20 parts by mass when the methacrylic copolymer (A) is 100 parts by mass. Thing . The curable composition according to any one of claims 1 to 3, which is used as an adhesive or a sealing agent. The methacrylic copolymer (A) is a polymerizable copolymer having butyl methacrylate, at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate, and a hydrolyzable silyl group. saturated compound, a monomer mixture containing a polymerization initiator, while supplying continuously to the reaction system, according to claim 1 to 4, which is a polymer obtained by polymerizing at a temperature of 0.99 ° C. to 350 ° C. The curable composition in any one. The methacrylic copolymer (A) is produced by living radical polymerization of a monomer component containing butyl methacrylate and at least one selected from methyl acrylate, methyl methacrylate, ethyl acrylate and ethyl methacrylate. The curable composition according to any one of claims 1 to 4 , which is a polymer obtained.