JP2023143745A - Epoxy resin composition, cured product, adhesive, molding material and fiber-reinforced plastic - Google Patents

Abstract

To provide: an epoxy resin composition capable of obtaining a cured product which exhibits excellent toughness and has high adhesive strength and impact strength and its cured product; an adhesive; a molding material; and a fiber-reinforced plastic.SOLUTION: There is provided an epoxy resin composition comprising a (meth)acrylic polymer (A) having a constitutional unit derived from a (meth)acrylate (a1) having a block isocyanate group and a constitutional unit derived from an alkyl (meth)acrylate (a2) and a curing agent, which can obtain a cured product exhibiting excellent toughness and having high adhesive strength and impact strength.SELECTED DRAWING: None

Description

The present invention relates to epoxy resin compositions, cured products, adhesives, molding materials, and fiber-reinforced plastics.

Epoxy resins have excellent rigidity, heat resistance, electrical properties, and durability, so they are used in adhesives such as vehicle structural adhesives, civil engineering and construction adhesives, electronic material adhesives, and industrial adhesives. It is used in materials such as fiber-reinforced plastics. On the other hand, epoxy resins are generally known to be brittle, and studies are being conducted to improve adhesive strength and impact strength by increasing their toughness.

For example, Patent Document 1 describes an epoxy resin and a structural unit derived from a macromonomer (
It is disclosed that a cured product having excellent adhesive strength and impact strength can be obtained from an epoxy resin composition containing a meth)acrylic polymer. Further, Patent Document 2 discloses that an epoxy resin composition containing a block urethane resin has high adhesive properties and can therefore be suitably used as a structural adhesive.

International Publication No. 2019/049951 JP 2018-2766 Publication

An object of the present invention is to provide an epoxy resin composition, a cured product thereof, an adhesive, a molding material, and a fiber-reinforced plastic from which a cured product exhibiting excellent toughness and high adhesive strength can be obtained. Another object of the present invention is to provide an epoxy resin composition from which a cured product having high impact strength can be obtained, a cured product thereof, an adhesive, a molding material, and a fiber-reinforced plastic.

The present invention has the following aspects.
[1] A (meth)acrylic polymer (A) having a structural unit derived from a (meth)acrylate (a1) having a blocked isocyanate group and a structural unit derived from an alkyl (meth)acrylate (a2), an epoxy resin (B) and an epoxy resin composition containing a curing agent (C).
[2] The epoxy resin composition according to [1], wherein the (meth)acrylic polymer (A) has a (meth)acrylate (a3) having a cyclic ether group as a constituent unit.
[3] The epoxy resin composition according to any one of [1] and [2], wherein the (meth)acrylic polymer (A) is a graft copolymer.
[4] The epoxy resin composition according to [3], wherein the graft copolymer has a constitutional unit derived from the vinyl radically polymerizable monomer (m1) and a constitutional unit derived from the macromonomer (M).
[5] The structural unit derived from the vinyl radically polymerizable monomer (m1) contains a structural unit derived from the (meth)acrylate (a1) having the blocked isocyanate group.
The epoxy resin composition described in ].
[6] The epoxy resin composition according to any one of [4] or [5], wherein the macromonomer (M) has a structural unit derived from a vinyl radically polymerizable monomer (m2).
[7] The epoxy resin composition according to [6], wherein the constitutional unit derived from the vinyl radically polymerizable monomer (m2) contains a constitutional unit derived from (meth)acrylate (a3) having a cyclic ether group. thing.
[8] The macromonomer (M) has a structure represented by the following formula (1), [4] to
The epoxy resin composition according to any one of [7].

(In formula (1), X ¹ to X ^n-1 are each independently a hydrogen atom, a methyl group, or a CH ₂ O
H, and Y ¹ to Y ⁿ each independently represent the vinyl radically polymerizable monomer (m2
), Z is a terminal group, and n is an integer from 2 to 10,000. )
[9] The epoxy resin composition according to any one of [1] to [8], further comprising a polymer (D) having a core-shell structure.
[10] An adhesive containing the epoxy resin composition according to any one of [1] to [9].
[11] A cured product of the epoxy resin composition according to any one of [1] to [9].
[12] A molding material containing the cured product according to [11].
[13] A fiber-reinforced plastic containing the cured product according to [11].

According to the present invention, it is possible to provide an epoxy resin composition from which a cured product exhibiting excellent toughness and high adhesive strength can be obtained, as well as its cured product, adhesive, molding material, and fiber-reinforced plastic. Further, according to the present invention, it is possible to provide an epoxy resin composition from which a cured product having high impact strength can be obtained, a cured product thereof, an adhesive, a molding material, and a fiber-reinforced plastic.

The present invention will be explained in detail below. The following embodiments are merely examples for explaining the present invention, and are not intended to limit the present invention only to these embodiments. The present invention
It can be implemented in various ways without departing from the spirit thereof.
In the present invention, "(meth)acrylic" is a general term for "acrylic" and "methacrylic". "(Meth)acrylate" is a generic term for "acrylate" and "methacrylate.""(Meth)acryloylgroup" is a general term for "acryloyl group" and "methacryloyl group", and is a group represented by CH ₂ =C(R)-C(=O)-(R is a hydrogen atom or a methyl group). It is. "Macromonomer" means a high molecular weight compound having a radically polymerizable group or an addition-reactive functional group. The number average molecular weight (Mn) is usually 1,000 to 1,000,000. "Vinyl-based radically polymerizable monomer" means a monomer having an ethylenically unsaturated bond that is not a macromonomer.

[Epoxy resin composition]
The epoxy resin composition of the present invention comprises the following (meth)acrylic polymer (A) (hereinafter referred to as "
(A) Component. ), epoxy resin (B) (hereinafter also referred to as "component (B)"), and curing agent (C) (hereinafter also referred to as "component (C)"). The epoxy resin composition of the present invention can further contain a polymer (D) having a core-shell structure. In addition, the epoxy resin composition of the present invention may contain components other than components (A) to (D) (hereinafter also referred to as "optional components") as necessary within a range that does not impair the effects of the present invention. May contain.

<(A) component>
Component (A) is a (meth)acrylic polymer.
The (meth)acrylic polymer (A) consists of a structural unit derived from (meth)acrylate (a1) (hereinafter also referred to as "component (a1)") having a blocked isocyanate group and an alkyl (
It has a structural unit derived from meth)acrylate (a2) (hereinafter also referred to as "component (a2)").
From the viewpoint of improving the solubility of component (A) in component (B) and improving the adhesive strength and impact resistance of the cured product, (a1 ) component and (a2
) It is preferable to contain the structural unit derived from the component in an amount of 50% by mass or more, more preferably 65% by mass or more, and still more preferably 80% by mass or more.
Component (A) may be used alone or in combination of two or more.

Component (a1) is a compound obtained by adding a blocking agent to the isocyanate group portion of a (meth)acrylate having an isocyanate group.
Examples of (meth)acrylates having an isocyanate group include 2-isocyanatoethyl (meth)acrylate, 2-isocyanatopropyl (meth)acrylate, 3-isocyanatopropyl (meth)acrylate, and 2-(2-(meth)acrylate). ) acryloyloxyethyloxy)ethyl isocyanate, 1,1-(bis(meth)acryloyloxymethyl)
Examples include ethyl isocyanate.

Examples of blocking agents include oxime-based blocking agents such as formaldoxime, acetaldoxime, acetoxime, methyl ethyl ketoxime, methyl isobutyl ketoxime, diethyl ketoxime, cyclohexanone oxime, diacetyl monoxime, and benzophenone oxime; ε-caprolactam; Lactam-based blocking agents such as γ-butyrolactam and β-propiolactam; methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, t-butanol, ethylene glycol,
Alcohol blocking agents such as 1-methoxy-2-propanol, methyl cellosolve, butyl cellosolve, methyl carbitol, benzyl alcohol, phenyl cellosolve, furfuryl alcohol, cyclohexanol; phenol, cresol, xylenol, ethyl phenol, o-isopropyl phenol, p-tert-butylphenol, p-te
rt-octylphenol, nonylphenol, dinonylphenol, styrenated phenol, oxybenzoic acid ester, thymol, p-naphthol, p-nitrophenol, p
- Phenol blocking agents such as chlorophenol; Pyrazole blocking agents such as 3,5-dimethylpyrazole; Amine blocking agents such as diphenylamine, phenylnaphthylamine, aniline, carbazole; Acid amides such as acetanilide, acetanicidide, acetamide, benzamide, etc. Imidazole blocking agents such as imidazole, 2-methylimidazole and 2-ethylimidazole; Acid imide blocking agents such as succinimide and maleic imide; Urea blocking agents such as urea, thiourea and ethylene urea ; Carbamate-based blocking agents such as phenyl N-phenylcarbamate and 2-oxazolidone; Imine-based blocking agents such as ethyleneimine and polyethyleneimine; Dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, acetylacetone, etc. active methylene blocking agents; mercaptan blocking agents such as butyl mercaptan, thiophenol and tert-dodecyl mercaptan; bisulfite blocking agents such as sodium bisulfite and potassium bisulfite.

Commercially available products of component (a1) include "Karens AOI-PAP (a compound in which p-hydroxyacetophenone is added to 2-isocyanatoethyl acrylate)" manufactured by Showa Denko;
Karenz AOI-SM (a compound in which methyl salicylate is added to 2-isocyanatoethyl acrylate)", "Karenz MOI-SM (a compound in which methyl salicylate is added to 2-isocyanatoethyl methacrylate)", "Karenz AOI-AM (a compound in which methyl salicylate is added to 2-isocyanatoethyl methacrylate)" - Compound with methyl parapene added to isocyanatoethyl acrylate)", "Karens MOI-DEM (2
-A compound in which diethyl malonate is added to isocyanatoethyl methacrylate)", "Karenz AOI-DEM (a compound in which diethyl malonate is added to 2-isocyanatoethyl acrylate)", "Karenz MOI-BP (a compound in which diethyl malonate is added to 2-isocyanatoethyl acrylate)" 3 to methacrylate,
``Karens AOI-BP (compound added with 3,5-dimethylpyrazole to 2-isocyanatoethyl acrylate)'', ``Karens MOI-BM (compound added with 3,5-dimethylpyrazole to 2-isocyanatoethyl methacrylate)'' ``Karens AOI-BM (compound with methyl ethyl ketoxime added to 2-isocyanatoethyl acrylate)'', ``Karens MOI-CP (compound with ε-caprolactam added to 2-isocyanatoethyl methacrylate)'' Compound)”, “Karens M
OI-MP (a compound in which 1-methoxy-2-propanol is added to 2-isocyanatoethyl methacrylate),” “Karens MOI-OEt (a compound in which ethanol is added to 2-isocyanatoethyl methacrylate),” “Karens MOI- OBu (a compound obtained by adding n-butanol to 2-isocyanatoethyl methacrylate)", "Karens MOI-Oi
Pr (compound obtained by adding i-propanol to 2-isocyanatoethyl methacrylate)"
etc.

Component (a1) may be used alone or in combination of two or more.
In component (a1), the blocking agent does not dissociate during the polymerization of component (A), the production of the epoxy resin composition, and the storage of the epoxy resin composition, and the blocking agent does not dissociate during the curing of the epoxy resin composition. Therefore, the dissociation temperature of the blocking agent is preferably 80 to 250°C, preferably 100 to 250°C.
220°C is more preferable, and 120 to 200°C is more preferable. Since the dissociation temperature of the blocking agent falls within a preferable range, the compounds listed above as commercial products are preferred, and "Karens MO
I-BP”, “Karens AOI-BP”, “Karens MOI-BM”, “Karens AOI
-BM,” “Karens MOI-CP,” and “Karens MOI-MP” are more preferred.
The content of component (a1) is determined from the viewpoint of improving the adhesive strength and impact resistance of the cured product.
It is preferably 0.05 to 50% by weight, more preferably 0.1 to 30% by weight, particularly preferably 0.2 to 10% by weight, based on 100% by weight of the total weight of the components.

Component (a2) is an alkyl (meth)acrylate having a linear or branched alkyl group. As the component (a2), for example, methyl (meth)acrylate, ethyl (
meth)acrylate, n-propyl(meth)acrylate, i-propyl(meth)acrylate, n-butyl(meth)acrylate, i-butyl(meth)acrylate, t-butyl(meth)acrylate, s-butyl(meth)acrylate Acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, n
-Octyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, n-undecyl (meth)acrylate, n-dodecyl (meth)acrylate, n-tridecyl (meth)acrylate, n-tetradecyl (meth)acrylate,
Cetyl (meth)acrylate, stearyl (meth)acrylate, behenyl (meth)acrylate, i-amyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, i-nonyl (meth)acrylate, i-decyl (meth)acrylate, 3-i-propylheptyl (meth)acrylate, i-undecyl (meth)acrylate, 2-t-butylheptyl (meth)acrylate, i-dodecyl (meth)acrylate, i-tridecyl (meth)acrylate, i-tetradecyl ( Examples include meth)acrylate.

Component (a2) may be used alone or in combination of two or more.
Component (a2) is an alkyl group having 1 to 18 carbon atoms because it can improve the solubility of component (A) in component (B) and improve the adhesive strength and impact resistance of the cured product. Alkyl (meth)acrylate containing a group is preferable, alkyl (meth)acrylate containing an alkyl group having 1 to 14 carbon atoms is more preferable, and alkyl (meth)acrylate containing an alkyl group having 1 to 12 carbon atoms. is even more preferable.

The content of component (a2) is determined from the viewpoint of improving the solubility of component (A) in component (B) and improving the adhesive strength and impact resistance of the cured product. Based on 100% by mass, the amount is preferably 30 to 99.9% by mass, more preferably 40 to 99% by mass, and even more preferably 50 to 98% by mass.

In order to improve the adhesive strength and impact resistance of the cured product, component (A) has a structure derived from (meth)acrylate (a3) having a cyclic ether group (hereinafter also referred to as "component (a3)"). It is preferable to contain units.
Examples of the (meth)acrylate (a3) having a cyclic ether group include tetrahydrofurfuryl (meth)acrylate, glycidyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether, and (meth)acryleoylmorpholine. , (3,4-epoxycyclohexyl)methyl (meth)acrylate, β-methylglycidyl (meth)acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, (2-methyl-2-ethyl-1) , 3-dioxolan-4-yl) (meth)acrylate, (5-ethyl-1,3-dioxan-5-yl)methyl (meth)acrylate,
Examples include (2-oxo-1,3-dioxolan-4-yl)methyl (meth)acrylate.

Component (a3) may be used alone or in combination of two or more.
By reacting with the curing agent (C), the adhesive strength and impact resistance can be particularly improved.
3) Components include glycidyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether, (3,4-epoxycyclohexyl)methyl (meth)acrylate, β-methylglycidyl (meth)acrylate, (2-oxo -1,3-dioxolan-4-yl)methyl (meth)acrylate is more preferred, and glycidyl (meth)
Acrylates are more preferred.
The blending amount of component (a3) is determined from the viewpoint of improving the adhesive strength and impact resistance of the cured product.
It is preferably 0 to 50% by weight, more preferably 1 to 40% by weight, even more preferably 2 to 30% by weight, based on 100% by weight of the total weight of the components.

Component (A) may contain vinyl radically polymerizable monomers other than components (a1) to (a3).
Other vinyl radically polymerizable monomers include, for example, monofunctional (meth)acrylates other than components (a1) to (a3), polyfunctional (meth)acrylates, and other vinyl compounds (hereinafter referred to as (Also referred to as "other vinyl compounds.").

Specific examples of monofunctional (meth)acrylates include (meth)acrylic acid, succinic acid 2-
(meth)acryloyloxyethyl, 2-(meth)acryloyloxyethyl maleate, 2-(meth)acryloyloxyethyl phthalate, 2-(meth)hexahydrophthalate
(Meth)acrylate containing a carboxyl group such as acryloyloxyethyl; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate,
2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, glycerin mono(meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, etc. (meth)acrylate having a hydroxyl group; cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenoxyethyl (meth)
Acrylate, (meth)acrylate having a cycloalkyl group such as dicyclopentanyl (meth)acrylate, adamantyl (meth)acrylate, 1,4-cyclohexanedimethanol monoacrylate; phenyl (meth)acrylate, benzyl (meth)acrylate, Phenoxyethyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, nonylphenoxypolyethylene glycol (meth)acrylate, phenoxypolypropylene glycol (meth)acrylate, phenyl phenyl (meth)acrylate, phenylphenoxyethyl ( (meth)acrylates having an aryl group such as meth)acrylate, phenoxybenzyl(meth)acrylate, phenylbenzyl(meth)acrylate, naphthyl(meth)acrylate, (1-naphthyl)methyl(meth)acrylate; methoxyethyl(meth)acrylate; Acrylate, Ethoxyethyl (meth)acrylate, Butoxyethyl (meth)
Acrylate, 2-ethylhexyloxyethyl (meth)acrylate, methoxydiethylene glycol (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, butoxydiethylene glycol (meth)acrylate, 2-ethylhexyloxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate
Acrylate, alkoxyalkyl (meth)acrylate such as methoxypolypropylene glycol (meth)acrylate; 2-isocyanatoethyl (meth)acrylate, 2-isocyanatopropyl (meth)acrylate, 3-isocyanatopropyl (meth)acrylate, 2- (2-(meth)acryloyloxyethyloxy)ethyl isocyanate, 1
(meth)acrylates having isocyanate groups such as , 1-(bis(meth)acryloyloxymethyl)ethyl isocyanate; (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, etc. (meth)acrylamide; 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 2-(meth)acryloyloxyethyl acid phosphate, trifluoroethyl (meth)acrylate, Examples include heptadecafluorodecyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, and the like.
These monofunctional (meth)acrylates may be used alone or in combination of two or more.

Specific examples of polyfunctional (meth)acrylates include ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, and propylene glycol di(meth)acrylate.
meth)acrylate, polypropylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, polybutylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, polycarbonate diol di(meth)acrylate, polyester diol di(meth)acrylate, bisphenol A ethylene oxide adduct di(meth)acrylate , bifunctional (meth)acrylates such as bisphenol A propylene oxide adduct di(meth)acrylate, polyurethane di(meth)acrylate, and 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl]fluorene. ;
Trifunctional (meth)acrylates such as trimethylolpropane tri(meth)acrylate, ethoxylated isocyanuric acid tri(meth)acrylate, and ε-caprolactone modified tris((meth)acryloxyethyl)isocyanurate; ditrimethylolpropane tetra(meth)acrylate; ) Tetrafunctional (meth)acrylates such as acrylate; Pentafunctional (meth)acrylates such as dipentaerythritol penta(meth)acrylate; Dipentaerythritol hexa(
Examples include hexafunctional (meth)acrylates such as meth)acrylates.
These polyfunctional (meth)acrylates may be used alone or in combination of two or more.

Other vinyl compounds are not particularly limited as long as they can be copolymerized with monofunctional (meth)acrylates and polyfunctional (meth)acrylates, but examples include styrene, α-methylstyrene, and pt-butylstyrene. , styrene or styrene derivatives such as vinyltoluene; unsaturated carboxylic acids such as itaconic acid, maleic acid, fumaric acid; unsaturated nitriles such as (meth)acrylonitrile; diethyl maleate, dibutyl maleate, dibutyl fumarate, diethyl itaconate , unsaturated carboxylic acid esters such as dibutyl itaconate; vinyl esters such as vinyl acetate and vinyl propionate.
One type of other vinyl radically polymerizable monomers may be used alone, or two or more types may be used in combination.

From the viewpoint of improving adhesive strength and impact resistance, other vinyl radically polymerizable monomers are preferably (meth)acrylates and alkoxyalkyl (meth)acrylates having hydroxyl groups, such as 2-hydroxyethyl (meth)acrylates. Acrylate, 2-hydroxypropyl (
More preferred are meth)acrylate, 2-hydroxybutyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, and methoxyethyl(meth)acrylate.

Component (A) may be a random copolymer, a block copolymer, or a graft copolymer. Graft copolymers are preferred because they can improve the solubility of component (A) in component (B) and can improve the adhesive strength and impact resistance of the cured product. The graft copolymer is not particularly limited as long as it has a branched structure in which a side chain polymer is bonded to a main chain polymer.
Also called. ) and a structural unit derived from the macromonomer (M) (hereinafter also referred to as "component (M)").

As the component (m1), the compounds mentioned above as the components (a1) to (a3) and other vinyl radically polymerizable monomers can be used. From the viewpoint of improving the adhesive strength and impact resistance of the cured product, it is preferable to contain components (a1) and (a2) as component (m1).
The macromonomer (M) is a high molecular weight compound having a radically polymerizable group or an addition-reactive functional group, and the number average molecular weight (Mn) is usually 1,000 to 1,000,000.

Component (M) is not particularly limited as long as it is a high molecular weight compound having a radically polymerizable group or an addition-reactive functional group. In view of the More preferably, it is a compound containing two or more units and having a radically polymerizable group at the end. Component (M) may be used alone or in combination of two or more.

As the component (m2), the compounds mentioned above as the components (a1) to (a3) and other vinyl radically polymerizable monomers can be used. From the viewpoint of solubility of component (A) in component (B), it is preferable to contain component (a3) as component (m2).

The component (M) preferably has a structure represented by the following general formula (1) from the viewpoint of excellent radical polymerizability with the component (m1).

In formula (1), X ¹ to X ^n-1 are each independently a hydrogen atom, a methyl group, or a CH ₂ O
H, and Y ¹ to Y ⁿ each independently represent the vinyl radically polymerizable monomer (m2
), Z is a terminal group, and n is an integer from 2 to 10,000.
Note that "-...-" in formula (1) represents a state in which the monomer units are polymerized.
X ¹ to X ^n-1 are preferably methyl groups, and from the viewpoint of ease of synthesis, preferably half or more are methyl groups.
Y ¹ to Y ⁿ are each independently a substituent other than X ¹ to X ^n-1 bonded to the vinyl group of the vinyl radically polymerizable monomer (m2). Such substituents include, for example, O
Examples include R ¹ , a halogen atom, COR ² , COOR ³ , CN, CONR ⁴ R ⁵ , NHCOR ⁶ , and R ⁷ . Note that R ¹ to R ⁷ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a cyclic ether group, an aryl group, a heteroaryl group, or the like.
Z is a terminal group. Examples of the terminal group include a hydrogen atom and a group derived from a radical polymerization initiator, similar to the terminal group of a polymer obtained by known radical polymerization.
n means the number of monomer units in one molecule of macromonomer (M). n is 2~
It is an integer of 10,000, preferably an integer of 5 to 1,000, and more preferably an integer of 10 to 500.

The number average molecular weight (Mn) of component (M) is preferably 1,000 to 30,000, and preferably 1,000 to 30,000.
20,000 is more preferable, and 1,000 to 10,000 is even more preferable. If the number average molecular weight of component (M) is within the above range, the solubility of component (A) in component (B) will be better.
The mass average molecular weight (Mw) of component (M) is preferably 1000 to 100000, and 100000 to 100000.
It is more preferably from 0 to 50,000, and even more preferably from 1,000 to 30,000. If the mass average molecular weight of component (M) is within the above range, the solubility of component (A) in component (B) will be better.

The Mw/Mn of the component (M) is preferably 1 to 5, more preferably 1.5 to 3. If the Mw/Mn of the component (M) is within the above range, the solubility of the component (A) in the component (B) will be better.
The number average molecular weight (Mn) and mass average molecular weight (Mw) of component (M) are polystyrene equivalent values measured by gel permeation chromatography (GPC), respectively.

Component (M) may be produced by a known method or may be commercially available.
As a method for producing component (M), for example, a method for producing using a cobalt chain transfer agent (
U.S. Pat. Examples include JP-A-60-133007 and US Pat. No. 5,147,952, etc.), thermal decomposition methods (JP-A-11-240854, etc.).

As a method for producing the component (M), a method using a cobalt chain transfer agent is preferable, since the number of production steps is small and a catalyst with a high chain transfer constant is used. Since the cobalt chain transfer agent has a high chain transfer constant, a component (M) with a controlled molecular weight can be obtained by adding a small amount.
As the cobalt chain transfer agent, known cobalt complexes can be used.
The amount of cobalt chain transfer agent used is 0.00001 parts by mass of component (m2).
~0.1 part by mass is preferred, 0.00005 to 0.05 part by mass is more preferred, and 0.00 part by mass is preferred.
01 to 0.02 parts by mass is more preferable.

From the viewpoint of improving the solubility of component (A) in component (B) and improving the adhesive strength and impact resistance of the cured product, the content of component (M) is set to 100% by mass of the total amount of component (A). 0 to 60 for %
It is preferably % by mass, more preferably 1 to 50% by mass, and even more preferably 5 to 40% by mass.
Component (A) and macromonomer (M) can be produced by known methods such as solution polymerization, suspension polymerization, emulsion polymerization, and redox polymerization.

The mass average molecular weight (Mw) of component (A) is preferably 10,000 to 1,000,000, and 2
0,000 to 800,000 is more preferable, and even more preferably 30,000 to 600,000.
If the mass average molecular weight of component (A) is within the above range, the solubility of component (A) in component (B) will be better.
The number average molecular weight (Mn) of component (A) is preferably 3,000 to 300,000, and preferably 5,000 to 3,000.
0 to 200,000 is more preferable, and 10,000 to 100,000 is even more preferable. (A)
If the number average molecular weight of the component is within the above range, the solubility of component (A) in component (B) will be better.

The Mw/Mn of component (A) is preferably 1 to 20, more preferably 1.5 to 15. (A
) If the Mw/Mn of the component is within the above range, the solubility of the component (A) in the component (B) will be better.
Note that the number average molecular weight (Mn) and mass average molecular weight (Mw) of component (A) are polystyrene equivalent values measured by gel permeation chromatography (GPC), respectively.

<(B) component>
Component (B) is an epoxy resin.
As the component (B), for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol E type epoxy resin,
Examples include naphthalene type epoxy resin, biphenyl type epoxy resin, dicyclopentadiene type epoxy resin, phenol novolac type epoxy resin, alicyclic epoxy resin, glycidylamine type epoxy resin, and the like.

In addition, as component (B), a prepolymer of the epoxy resin, a copolymer of the epoxy resin and another polymer such as a polyether-modified epoxy resin, a silicone-modified epoxy resin, and a part of the epoxy resin are used. may also be substituted with a reactive diluent having an epoxy group.
Examples of the reactive diluent include resorcin glycidyl ether, t-butylphenyl glycidyl ether, 2-ethylhexyl glycidyl ether, allyl glycidyl ether, phenyl glycidyl ether, 3-glycidoxypropyltrimethoxysilane, and 3-glycidyl ether.
Glycidoxypropylmethyldimethoxysilane, 1-(3-glycidoxypropyl)-1
, 1,3,3,3-pentamethylsiloxane, N-glycidyl-N,N-bis[3-(trimethoxysilyl)propyl]amine; 2-(3,4)-epoxycyclohexyl) Examples include monoalicyclic epoxy compounds such as ethyltrimethoxysilane. These reactive diluents may be used alone or in combination of two or more.
Among these, bisphenol A-type epoxy resins and bisphenol F-type epoxy resins are preferred as component (B) because they are liquid and easy to handle, and have a high glass transition point, which further increases the adhesive strength of the cured product.
These (B) components may be used alone or in combination of two or more.

<(C) component>
Component (C) cures component (B) and is used to adjust the curability and properties of the cured product of the epoxy resin composition.
As component (C), known components can be used, such as acid anhydrides, amine compounds, phenol compounds, latent curing agents, and the like.

Specific examples of component (C) include phthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride,
Trialkyltetrahydrophthalic anhydride, methylhimic anhydride, methylcyclohexenedicarboxylic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, ethylene glycol bistrimelitate, glycerol tristrimelitate, dodecenyl Acid anhydrides such as succinic anhydride, polyazelaic anhydride, poly(ethyl octadecanedioic acid) anhydride; 2,5(2,6)-bis(aminomethyl)bicyclo[2
,2,1]heptane, isophoronediamine, ethylenediamine, diethylenetriamine,
triethylenetetramine, tetraethylenepentamine, diethylaminopropylamine,
Bis(4-amino-3-methyldicyclohexyl)methane, diaminodicyclohexylmethane, bis(aminomethyl)cyclohexane, bis(aminomethyl)norbornane, bis(4-aminocyclohexyl)methane, metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone , diaminodiethyldiphenylmethane, diethyltoluenediamine, 3,3'-diaminodiphenylsulfone (3,3'-DDS), 4,4'
- Diaminodiphenylsulfones such as diaminodiphenylsulfone (4,4'-DDS), diaminodiphenyl ether (DADPE), bisaniline, dimethylaniline, triethylenediamine, dimethylbenzylamine, 2,4,6-tris(dimethylaminomethyl)phenol , benzyldimethylaniline, 3,3'-dichloro-4,4'-diaminodiphenylmethane (MOCA), 4,4'-diaminodiphenylmethane, 2,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4 '-Diaminodiphenylmethane, 2,2'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,
4-diaminophenol, 2,5-diaminophenol, o-phenylenediamine, m-
Phenylene diamine, p-phenylene diamine, m-xylylene diamine, 2,3-tolylene diamine, 2,4-tolylene diamine, 2,5-tolylene diamine, 2,6-tolylene diamine, 3,4- Amine compounds such as tolylene diamine, methylthiotoluenediamine, diethyltoluenediamine, dicyandiamide; phenolic compounds such as phenol novolak resin, cresol novolak resin, bisphenol A, bisphenol F, bisphenol AD, and diallylated derivatives of these bisphenols; Hydrazide, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, iminodiacetic acid dihydrazide, adipic acid dihydrazide, pimelic acid dihydrazide, suberic acid dihydrazide, azelaic acid dihydrazide, sebacic acid dihydrazide, dodecane dihydrazide, hexadecane dihydrazide, maleic acid dihydrazide , fumaric acid Dihydrazide, diglycolic acid dihydrazide, tartaric acid dihydrazide, malic acid dihydrazide, isophthalic acid dihydrazide, terephthalic acid dihydrazide, 2,6-naphthoic acid dihydrazide, 4,4'-bisbenzene dihydrazide, 1,4-naphthoic acid dihydrazide, Amicure VDH, Examples include hydrazide compounds such as Amicure UDH (both trade names, manufactured by Ajinomoto Co., Ltd.) and citric acid trihydrazide.

Among these, (C
) As the component, amine compounds and hydrazide compounds are preferable, and dicyandiamide and hydrazide compounds are more preferable.
These (C) components may be used alone or in combination of two or more.

<(D) component>
Component (D) is a polymer having a core-shell structure. (D) By adding the ingredient,
The adhesive strength and impact strength of the cured product can be further increased. The structure of component (D) is such that the core layer is one or more selected from the group consisting of a diene rubber polymer, an acrylic rubber polymer, and an organosiloxane rubber polymer, and the shell layer is a vinyl polymer. It is preferable that there be.
Examples of the diene rubber polymer include a copolymer consisting of 1,3-butadiene, a vinyl monomer copolymerizable therewith, and, if necessary, a crosslinkable monomer.

For ease of blending component (D) into component (B), it is preferable to remove water and emulsifier from the latex and replace it with an epoxy resin to handle it as an "epoxy dispersion of component (D)."
As the epoxy dispersion liquid of component (D), a commercially available product may be used. Commercially available products include the product name "Kane Ace MX Series" manufactured by Kaneka Corporation. "Kane Ace MX154", which is an example of the "Kane Ace MX series", has a core layer made of polybutadiene and a shell layer made of vinyl polymer (approximately 40% by mass), and bisphenol A epoxy resin (approximately 60% by mass). ) is a dispersion liquid in which single particles are dispersed.

<Optional ingredients>
Examples of optional components include 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), 2-methylimidazole, 2-ethyl-4-methylimidazole, and an adduct of an imidazole compound and an epoxy resin. curing accelerators such as triphenylphosphine, tetraphenylphosphine tetraphenylborate, diazabicycloundecene (DBU); 2,6-di-t-butylphenol, 2,6-di-t-butyl-p-cresol , n-octadecyl-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate, tetrakis-[methylene-3-(3',5'-di-t-butyl-
4'-Hydroxyphenyl)propionate]methane, triethylene glycol bis[3
-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6
-Hexanediolbis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], triethyl phosphite, tri(2-ethylhexyl) phosphite,
tridecyl phosphite, triphenyl phosphite, trisisodecyl phosphite,
Tristridecyl phosphite, tris(2,4-di-t-butylphenyl) phosphite, dihexyl sulfide, dilauryl-3,3'-thiodipropionate, ditridecyl-3,3'-thiodipropionate, dimyristyl -3,3'-thiodipropionate, disterial-3,3'-thiodipropionate, pentaerythritol tetrakis (
Antioxidants such as β-laurylthiopropionate; silicone oil, natural wax,
Mold release agents such as synthetic wax; fillers such as glass beads, crystalline silica, fused silica, calcium silicate, alumina, calcium carbonate; fibers such as glass fiber, carbon fiber, alumina fiber, cellulose nanofiber; antimony trioxide, etc. flame retardants; halogen trapping agents such as hydrotalcite and rare earth oxides; coloring agents such as carbon black and red iron; silane coupling agents; antifoaming agents; rheology modifiers: pigments; dyes and the like.
These optional components may be used alone or in combination of two or more.

<Content>
When the total mass of the components (A) to (D) is 100% by mass, the preferred content of each component is as follows.
The content of component (A) is preferably 1 to 60% by mass, and 5 to 60% by mass, since this makes it possible to make the epoxy resin composition a low viscosity with good workability while further increasing the toughness and adhesive strength of the cured product.
It is more preferably 55% by mass, and even more preferably 10 to 50% by mass.
The content of component (B) is preferably 20 to 90% by mass, more preferably 30 to 80% by mass, and 40 to 7% by mass, since the epoxy resin composition can have a low viscosity with good workability.
0% by mass is more preferred.
The content of component (C) is preferably 0.1 to 10% by mass, since this provides good storage stability of the epoxy resin composition and sufficient curability to obtain a cured product. 0.5
It is more preferably 9% by weight, and even more preferably 1-8% by weight.
The content of component (D) is preferably 0 to 40% by mass, and 1 to 40% by mass, since it can make the epoxy resin composition have a low viscosity with good workability and further increase the toughness and adhesive strength of the cured product.
It is more preferably 35% by mass, and even more preferably 3 to 30% by mass.

<Manufacturing method>
There are no particular limitations on the method for producing the epoxy resin composition, and any known method can be used. For example, component (A), component (B), component (C), optional component (D), and optional components may be mixed simultaneously, and some components (for example, component (A)) may be mixed simultaneously. and (B) component) may be mixed in advance, and the mixture and the remaining components may be mixed.
The mixing method is not particularly limited, and known mixers such as an autorotation/revolution mixer, a three-roll mixer, a kneader, etc. can be used.

<Effect>
The epoxy resin composition of the present invention explained above includes the above-mentioned (A) component, (B) component and (
Since it contains component C), component (D) if necessary, and optional components, a cured product exhibiting excellent toughness and having high adhesive strength and impact strength can be obtained. In addition, the epoxy resin composition of the present invention contains the above-mentioned components (A), (B), and (C), and if necessary, component (D) and optional components, so it has high impact strength. A cured product having the following properties is obtained.

<Application>
The epoxy resin composition of the present invention exhibits excellent toughness and yields a cured product having high adhesive strength and impact strength, and is therefore useful as adhesives, molding materials, and fiber-reinforced plastics.
Note that the uses of the epoxy resin composition of the present invention are not limited to the above. The epoxy resin composition of the present invention can also be used for other uses, for example, for various uses where thermosetting resins such as epoxy resins are used. Examples of such uses include paints, coatings, insulating materials, encapsulants, and the like.
Adhesives, molding materials, and fiber-reinforced plastics containing the epoxy resin composition of the present invention will be described below.

[glue]
The adhesive of the present invention contains the epoxy resin composition of the present invention described above.
Examples of adhesives include vehicle adhesives including structural adhesives for automobiles, civil engineering and construction adhesives, electronic materials adhesives, general office adhesives, medical equipment adhesives, industrial adhesives, etc. can be mentioned.
Examples of vehicle adhesives include hemming adhesives, weld bond adhesives, mastic adhesives, direct glazing adhesives, spot sealers, body sealers, and undercoats.
Adhesives for electronic materials include, for example, interlayer adhesives for multilayer boards such as build-up boards, die bonding agents, adhesives for semiconductors such as underfill, underfill for reinforcing BGA,
Examples include mounting adhesives such as anisotropic conductive film (ACF) and anisotropic conductive paste (ACP).
These adhesive applications require high adhesive strength and impact strength.

[Cured product]
The cured product of the present invention is obtained by curing the epoxy resin composition of the present invention described above.
The method for curing the epoxy resin composition is not particularly limited, and any known method can be used, such as a thermosetting method.
When curing an epoxy resin composition by a thermosetting method, (C
) The epoxy resin composition is preferably cured under heating conditions, for example, at 50 to 250° C. for about 0.1 to 10 hours, although optimal conditions vary depending on the type and amount of the components.

[Molding material]
The molding material of the present invention contains a cured product of the epoxy resin composition of the present invention described above.
As the molding material, for example, a sheet obtained by curing the epoxy resin composition of the present invention,
Examples include films. Examples of the molding method include techniques such as transfer molding and cast molding. Applications of the molding material include, for example, aircraft parts, automobile parts, sporting goods, building materials, electronic circuit boards, semiconductor encapsulants, reflectors for optical semiconductors, and the like.
These molding materials are required to have excellent toughness and high impact strength.

[Fiber reinforced plastic]
Fiber Reinforced Plastic (FRP) of the present invention
stics) is a cured prepreg obtained by impregnating fibers such as glass fibers and carbon fibers with the epoxy resin composition of the present invention.
Examples of uses for fiber-reinforced plastics include aircraft parts, automobile parts, ship parts,
Examples include sporting goods, building materials, wind turbine blades, gas tanks, robots, and electronic circuit boards.
These fiber-reinforced plastics are required to have excellent toughness and high impact strength. Also,
The epoxy resin composition used for impregnation is required to have high adhesive strength to fibers.

EXAMPLES Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to the following Examples unless it exceeds the gist thereof. In each of the following examples, "parts" indicate "parts by mass" and "%" indicate "% by mass" unless otherwise specified.

[Measurement/evaluation method]
<Measurement of molecular weight of macromonomer (M)>
The molecular weight of the component (M) was measured as follows using a gel permeation chromatograph (GPC device) (manufactured by Tosoh Corporation, product name "HLC-8320").
A THF solution (1) was prepared by dissolving component (M) in tetrahydrofuran (THF) to a concentration of 0.2% by mass.
Tosoh Co., Ltd. column (TSKgel SuperHZM-M (inner diameter 4.6 mm, length 1
5cm) 1 piece, HZM-M (inner diameter 4.6mm, length 15cm) 1 piece, HZ-2000 (inner diameter 4.6mm, length 15cm) 1 piece, TSKguardcolumn SuperHZ-
10 μL of the above THF solution (1) was injected into a GPC device equipped with a tube (inner diameter 4.6 mm, length 3.5 cm), flow rate: 0.35 mL/min, eluent: dibutyl as a stabilizer. Measurement was performed using THF containing hydroxytoluene (BHT) at a column temperature of 40° C., and the mass average molecular weight (Mw) and number average molecular weight (Mn) were calculated in terms of standard polystyrene.

<Measurement of molecular weight of (meth)acrylic polymer (A)>
The molecular weight of the (meth)acrylic polymer (A) was measured as follows using a gel permeation chromatograph (GPC device) (manufactured by Tosoh Corporation, product name "HLC-8320").
A THF solution (2) was prepared by dissolving the (meth)acrylic polymer (A) in tetrahydrofuran (THF) to a concentration of 0.2% by mass.
Tosoh Co., Ltd. column (TSKgel SuperHZM-H (inner diameter 6.0 mm, length 1
5cm) 2 pieces, TSKguardcolumn SuperHZ-H (inner diameter 4.6mm,
Inject 10 μL of the above THF solution (2) into a GPC device equipped with a 3.5 cm length (1 tube), flow rate 0.5 mL/min, eluent: THF containing BHT as a stabilizer, column temperature: Measurement was performed at 40° C., and the mass average molecular weight (Mw) and number average molecular weight (Mn) were calculated in terms of standard polystyrene.

<Evaluation of toughness and adhesive strength>
Grab a steel plate (manufactured by Engineering Test Service Co., Ltd., product name: JIS G3141, SPCC-SD) with a width of 25 mm, a length of 150 mm, and a thickness of 0.5 mm up to 50 mm from one end in the length direction, and then An epoxy resin composition was applied to the area. Another steel plate of similar size is pasted on the surface coated with the epoxy resin composition, fixed so that the thickness of the epoxy resin composition layer is constant, and heated at 180°C for 30 minutes to make the epoxy resin. The composition was cured to obtain a laminate. The cured product of the epoxy resin composition protruding from the side surface of the obtained laminate was scraped off, and the gripping portions of each of the two steel plates were cut at right angles to the outside.
A T-shaped test piece was obtained by bending at 0°.
Using a precision universal testing machine (manufactured by Shimadzu Corporation, product name: Autograph AGX-10kNVD, load cell 1kN), hold the gripping portion of the obtained test piece vertically,
Peel strength was measured under the conditions of 10 minutes. Measurements were carried out at 23°C. first 25mm and last 25mm
The average value of the loads excluding mm was taken as the T-peel strength. The T-peel strength was measured for the three test pieces, the average value thereof was determined, and the adhesive strength was evaluated. The higher the T-peel strength, the better the adhesive strength. Further, the higher the T-peel strength, the better the toughness.

<Evaluation of toughness and impact strength>
A symmetrical wedge test piece was prepared in accordance with ISO11343 and JIS K6865, and the impact strength was measured. Bending steel plate with a thickness of 0.8 mm (JIS G3141, SPCC-S
D, manufactured by Engineering Test Service Co., Ltd.) was coated with an epoxy resin composition and bonded together, and the epoxy resin was cured by heating at 180° C. for 30 minutes to obtain a symmetrical wedge test piece. High-speed tensile testing machine Hydroshot HITS-T10 (manufactured by Shimadzu Corporation, load cell 1
A symmetrical wedge test piece was driven at 2 m/s using a force of 0 kN) to a width of 20 mm and a length of 3.
The dynamic cleavage resistance value during cleavage of a 0 mm cured epoxy resin product was measured. Measurements were carried out at 23°C. The average value of the dynamic cleavage resistance values between the first 25% and the last 10% of the moving distance was defined as the impact strength. Moreover, the higher the impact strength, the better the toughness.

[Dispersant]
<Synthesis Example 1: Synthesis of dispersant (1)>
In a polymerization apparatus equipped with a stirrer, a cooling tube, a thermometer and a nitrogen gas inlet tube, 900 g of deionized water was added.
1 part, 60 parts of sodium 2-sulfoethyl methacrylate, 10 parts of potassium methacrylate, and 12 parts of methyl methacrylate (MMA) were added and stirred, while purging the inside of the polymerization apparatus with nitrogen.
The temperature was raised to 50°C. Thereto was added 0.08 part of 2,2'-azobis(2-methylpropionamidine) dihydrochloride as a polymerization initiator, and the temperature was further raised to 60°C. After raising the temperature, MMA was continuously added dropwise for 75 minutes at a rate of 0.24 parts/min using a dropping pump. The reaction solution was maintained at 60° C. for 6 hours and then cooled to room temperature to obtain a dispersant (1) having a solid content of 10% as a transparent aqueous solution.

[Chain transfer agent]
<Synthesis Example 2: Synthesis of chain transfer agent (1)>
Cobalt(II) acetate tetrahydrate 1.
00 g, 1.93 g of diphenylglyoxime, and 80 mL of diethyl ether which had been previously deoxidized by nitrogen bubbling were added, and the mixture was stirred at room temperature for 30 minutes. Next, 10 mL of boron trifluoride diethyl ether complex was added, and the mixture was further stirred for 6 hours. The mixture was filtered and the solid was washed with diethyl ether and dried under vacuum for 15 hours to obtain the chain transfer agent (1), which is a reddish-brown solid.2.
12g was obtained.

<Production Example 1: Production of macromonomer (M1)>
In a polymerization apparatus equipped with a stirrer, a cooling tube, a thermometer and a nitrogen gas inlet tube, 145 liters of deionized water was added.
1 part, 0.1 part of sodium sulfate, and 0.25 part of dispersant (1) (solid content 10%) were added and stirred to obtain a uniform aqueous solution. 50 parts of methyl methacrylate as the component (a2), 50 parts of glycidyl methacrylate as the component (a3), 0.0040 parts of the chain transfer agent (1), and 1,1,3,3-tetramethylbutylperoxy- as the polymerization initiator. Two parts of 2-ethylhexanoate (manufactured by NOF Corporation, trade name "Perocta O") was added to form an aqueous suspension.
Next, the inside of the polymerization apparatus was purged with nitrogen, the temperature was raised to 80°C, and reaction was carried out for 3.5 hours, and in order to further increase the polymerization rate, the temperature was raised to 90°C and held for 1 hour. Thereafter, the reaction solution was cooled to 40° C. to obtain an aqueous suspension containing the macromonomer. The aqueous suspension was filtered and the residue left on the filter was washed with deionized water, dehydrated and dried at 40° C. for 16 hours to obtain the macromonomer (M1).
The molecular weight of the obtained macromonomer (M1) was measured. The results are shown in Table 1.

The abbreviations in Table 1 are as follows.
・MMA: Methyl methacrylate (manufactured by Mitsubishi Chemical, trade name "Acryester M").
・GMA: Glycidyl methacrylate (manufactured by Mitsubishi Chemical, trade name "Acryester G")
.
- Chain transfer agent (1): Chain transfer agent synthesized in Synthesis Example 2.
- Perocta O: 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate (manufactured by NOF Corporation, trade name "Perocta O").

<Production Example 2: Production of (meth)acrylic polymer (A-1)>
40 parts of methyl ethyl ketone (MEK) and 20 parts of macromonomer (M1) were put into a four-necked flask equipped with a stirrer, a thermometer, a cooling tube, and a nitrogen gas inlet as an initial charging solvent, and nitrogen gas was introduced while stirring. At the bottom, the external temperature was raised to 85°C. After the external temperature reached 85°C and the internal temperature stabilized, 25 parts of MEK and 1-methoxy-2-propanol was added to Karenz MOI-MP (manufactured by Showa Denko, 2-isocyanatoethyl methacrylate) as the (a1) component. A mixture consisting of 1 part of compound), 79 parts of ethyl acrylate as component (a2), and 0.13 parts of benzoyl peroxide (manufactured by NOF Corporation, trade name: "Niper BMT-K40") as a polymerization initiator was added over 4 hours. dripped. After holding for 1 hour after completion of the dropping, 0.5 part of 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (manufactured by NOF Corporation, trade name "Perocta O") was added as a polymerization initiator. and 10 parts of MEK was added over 1 hour. Then, after holding for 2 hours, MEK was added so that the solid content (ratio of monomer charge in (monomer + solvent charge)) was 50%, and then cooled to room temperature (meta).
An MEK solution of acrylic polymer (A-1) was obtained.
The molecular weight of the obtained (meth)acrylic polymer (A-1) was measured. The results are shown in Table 2.

<Production Examples 3 to 23: Production of (meth)acrylic polymers (A-2) to (A-22)>
Production example except that the types and amounts of component (M), components (a1) to (a3), other vinyl radically polymerizable monomers, and initial charging solvent were changed to those shown in Tables 2 to 4. Solutions of (meth)acrylic polymers (A-2) to (A-22) were obtained in the same manner as in 2. Tables 2 to 4 show the results of measuring the molecular weights of the obtained acrylic polymers (A-2) to (A-22).

The abbreviations in Tables 2 to 4 are as follows.
-M1: Macromonomer produced in Production Example 1.
・MOI-MP: A compound obtained by adding 1-methoxy-2-propanol to 2-isocyanatoethyl methacrylate (manufactured by Showa Denko Co., Ltd., product name "Karens MOI-MP")
・MOI-CP: Compound with ε-caprolactam added to 2-isocyanatoethyl methacrylate (manufactured by Showa Denko, trade name "Karens MOI-CP")
・MOI-BM: A compound obtained by adding methyl ethyl ketone oxime to 2-isocyanatoethyl methacrylate (manufactured by Showa Denko, trade name "Karens MOI-BM")
- MMA: Methyl methacrylate (manufactured by Mitsubishi Chemical Corporation, trade name "Acryester M").
- EA: Ethyl acrylate (manufactured by Mitsubishi Chemical Corporation, trade name "Ethyl acrylate").
・nBA: n-butyl acrylate (manufactured by Mitsubishi Chemical Corporation, trade name "butyl acrylate")
.
・GMA: Glycidyl methacrylate (manufactured by Mitsubishi Chemical Corporation, trade name "Acryester G")
).
・4HBA: 4-hydroxybutyl acrylate (manufactured by Shinryosha, product name "4HBA")
・2MTA: 2-methoxymethyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name “2-M”)
TA”)
・MEK: Methyl ethyl ketone.
・IPA: Isopropyl alcohol.

[Example 1]
50 parts of bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, trade name "jER828") was mixed with 100 parts of the MEK solution of the (meth)acrylic polymer (A-1) obtained in Production Example 2, and the mixture was heated under vacuum. By distilling MEK off under reduced pressure using a dryer, a (meth)acrylic polymer (
A (meth)acrylic polymer-containing epoxy resin containing 50 parts of A-1) was obtained.
In a mixing container, 60 parts of (meth)acrylic polymer-containing epoxy resin as components (A) and (B) (breakdown: 30 parts of (meth)acrylic polymer (A-1), 30 parts of jER828)
part), 20 parts of jER828 as component (B), and dicyandiamide (as component (C)).
4 parts of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (manufactured by Hodogaya Chemical Co., Ltd., trade name "DCMU") as a curing accelerator (manufactured by Mitsubishi Chemical Corporation, trade name "DICY7")
), 15.2 parts of calcium carbonate (manufactured by Shiraishi Calcium Co., Ltd., trade name "Whiten B") as a filler, and glass beads (manufactured by Potters Ballotini Co., Ltd., trade name "J-
Add 0.8 part of ``Awatori Rentaro'' (product name: ``Awatori Rentaro'', manufactured by Shinky Co., Ltd.).
An epoxy resin composition was prepared.
Using the obtained epoxy resin composition, adhesive strength was evaluated. The results are shown in Table 5.

[Examples 2 to 16, Comparative Examples 1 and 2]
An epoxy resin composition was prepared in the same manner as in Example 1, except that the type of component (A) and the blending amount of each component were changed to those shown in Tables 5, 6, and 8.
Using the obtained epoxy resin composition, adhesive strength and evaluation were performed. The results are shown in Tables 5 and 6.
8.

[Example 17]
50 parts of bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, trade name "jER828") was mixed with 100 parts of the (meth)acrylic polymer (A-1) solution obtained in Production Example 2,
By distilling off MEK under reduced pressure using a vacuum dryer, (meth)acrylic polymer (A-1)
A (meth)acrylic polymer-containing epoxy resin containing 50 parts of was obtained.
In a mixing container, 32 parts of (meth)acrylic polymer-containing epoxy resin as components (A) and (B) (breakdown: 16 parts of (meth)acrylic polymer (A-1), 16 parts of jER828)
part), 18 parts of jER828 as the (B) component, 4 parts of dicyandiamide as the (C) component, and 3 parts of Kaneka's product name "Kane Ace MX154" as the (D) and (B) components.
0 parts (breakdown: 12 parts of polymer with core-shell structure, 18 parts of bisphenol A type epoxy resin) and 0.8 parts of 3-(3,4-dichlorophenyl)-1,1-dimethylurea as a curing accelerator. , 15.2 parts of calcium carbonate (manufactured by Shiraishi Calcium Co., Ltd., trade name "Whiten B") and glass beads (manufactured by Potters Ballotini Co., Ltd., trade name "Whiten B") as fillers.
J-100'') was added and mixed using a stirring defoaming device (manufactured by Shinky Co., Ltd., product name ``Awatori Rentaro'') to prepare an epoxy resin composition.
Using the obtained epoxy resin composition, adhesive strength and impact strength were evaluated. The results are shown in Table 6.

[Examples 18-29, Comparative Examples 3 and 4]
An epoxy resin composition was prepared in the same manner as in Example 17, except that the type of component (A) was changed to the values shown in Tables 6 to 8.
Using the obtained epoxy resin composition, adhesive strength and impact strength were evaluated. The results are shown in Tables 6-8.

[Comparative example 5]
In a mixing container, 30 parts of QR-9466 (manufactured by ADEKA) as a block urethane resin, 50 parts of jER828 as the (B) component, and 4 parts of dicyandiamide (manufactured by Mitsubishi Chemical Corporation, trade name "DICY7") as the (C) component. and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (manufactured by Hodogaya Chemical Industry Co., Ltd., trade name "DCMU") as a curing accelerator.
．． Part 8, calcium carbonate as a filler (manufactured by Shiraishi Calcium Co., Ltd., product name "Whiten B")
) 15.2 parts and glass beads (manufactured by Potter's Ballotini, product name "J-100")
'') was added and mixed using a stirring defoaming device (manufactured by Shinky Co., Ltd., product name ``Awatori Rentaro'') to prepare an epoxy resin composition.
Using the obtained epoxy resin composition, adhesive strength was evaluated. The results are shown in Table 8.

The abbreviations in Tables 5 to 8 are as follows.
- A-1 to A-22: (meth)acrylic polymers (A) produced in Production Examples 2 to 23.
・jER828: Bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, product name "jER")
828”).
- Bis A epoxy: Bisphenol A epoxy resin contained in Kaneka's product name "Kane Ace MX154".
- DICY: dicyandiamide (manufactured by Mitsubishi Chemical Corporation, trade name "DICY7").
-DCMU: 3-(3,4-dichlorophenyl)-1,1-dimethylurea (manufactured by Hodogaya Chemical Industry Co., Ltd., trade name "DCMU").
- Whiten B: Calcium carbonate (manufactured by Shiroishi Calcium Co., Ltd., trade name "Whiten B").
・J-100: Glass beads (manufactured by Potter's Ballotini, product name "J-100")
.
- MX154: A polymer with a core-shell structure included in the product name "Kane Ace MX154" manufactured by Kaneka Corporation.
・QR-9466: Block urethane resin (manufactured by ADEKA, product name "QR-9466")
)

As is clear from Tables 5 to 8, the cured products of the epoxy resin compositions obtained in each example had excellent adhesive strength and impact strength.
On the other hand, the cured products of the epoxy resin compositions obtained in each comparative example were inferior in adhesive strength and impact strength.

The epoxy resin composition of the present invention can be used as a cured product exhibiting excellent toughness and having high adhesive strength and impact strength.・Useful as adhesives such as architectural adhesives, electronic material adhesives, general office adhesives, medical adhesives, industrial adhesives, molding materials, fiber-reinforced plastics, etc.

Claims (13)

(meth)acrylic polymer (A) having a structural unit derived from (meth)acrylate (a1) having a blocked isocyanate group and a structural unit derived from alkyl (meth)acrylate (a2), epoxy resin (B), and curing agent An epoxy resin composition containing (C). The epoxy resin composition according to claim 1, wherein the (meth)acrylic polymer (A) has a (meth)acrylate (a3) having a cyclic ether group as a constituent unit. The epoxy resin composition according to claim 1, wherein the (meth)acrylic polymer (A) is a graft copolymer. The graft copolymer has a structural unit derived from a vinyl radically polymerizable monomer (m1),
The epoxy resin composition according to claim 3, which has a structural unit derived from the macromonomer (M). The epoxy resin composition according to claim 4, wherein the structural unit derived from the vinyl radically polymerizable monomer (m1) contains a structural unit derived from the (meth)acrylate (a1) having the blocked isocyanate group. The epoxy resin composition according to claim 4, wherein the macromonomer (M) has a structural unit derived from a vinyl radically polymerizable monomer (m2). The epoxy resin composition according to claim 6, wherein the structural unit derived from the vinyl radically polymerizable monomer (m2) contains a structural unit derived from (meth)acrylate (a3) having a cyclic ether group. The epoxy resin composition according to claim 4, wherein the macromonomer (M) has a structure represented by the following formula (1).

(In formula (1), X ¹ to X ^n-1 are each independently a hydrogen atom, a methyl group, or a CH ₂ O
H, and Y ¹ to Y ⁿ each independently represent the vinyl radically polymerizable monomer (m2
), Z is a terminal group, and n is an integer from 2 to 10,000. ) The epoxy resin composition according to any one of claims 1 to 8, further comprising a polymer (D) having a core-shell structure. An adhesive comprising the epoxy resin composition according to any one of claims 1 to 8. A cured product of the epoxy resin composition according to any one of claims 1 to 8. A molding material containing the cured product according to claim 11. A fiber reinforced plastic containing the cured product according to claim 11.