KR20220123259A - Epoxy resin composition and cured resin - Google Patents

Abstract

An object of the present invention is to provide an epoxy resin composition capable of forming a cured resin product having excellent impact resistance. The epoxy resin composition of the present invention is an epoxy resin composition containing an epoxy resin (A) having a solubility parameter (SP value) of 11 to 15 and a (meth)acrylic polymer (B) having an SP value of 9.5 to 11, The meth)acrylic polymer (B) is a reaction product of the carboxyl group-containing (meth)acrylic polymer (B1) and the epoxy compound (B2), and the SP value of the (meth)acrylic polymer (B) and the epoxy resin ( It is characterized in that the absolute value of the difference with the SP value of A) is 0.1 to 3.3.

Description

Epoxy resin composition and cured resin

The present invention relates to an epoxy resin composition and a cured resin product.

Epoxy resins are used in a wide range of fields, such as adhesives and sealants, because of their excellent physical properties (for example, refer to Patent Documents 1 and 2). Epoxy resins are usually cured and used as cured resins.

Japanese Patent Application Laid-Open No. 2002-080696 International Publication No. 2017/195902

The cured resin obtained from an epoxy resin may be inferior in impact resistance. For example, in patent document 2, although an acrylic polymer is added with respect to an epoxy resin, according to examination of the present inventors, it turned out that the impact resistance of the resin hardened|cured material obtained in such an aspect is not enough.

An object of one aspect of the present invention is to provide an epoxy resin composition capable of forming a cured resin material having excellent impact resistance, and a cured resin material comprising the epoxy resin composition, which has been made in view of the above circumstances.

The present invention relates to, for example, the following [1] to [8].

[1] An epoxy resin composition comprising an epoxy resin (A) having a solubility parameter (SP value) of 11 to 15 and a (meth)acrylic polymer (B) having an SP value of 9.5 to 11, the (meth)acrylic polymer (B) is a reaction product of a carboxyl group-containing (meth)acrylic polymer (B1) and an epoxy compound (B2), and the SP value of the (meth)acrylic polymer (B) and the SP value of the epoxy resin (A) An epoxy resin composition in which the absolute value of the difference is 0.1 to 3.3.

[2] The epoxy resin composition according to the above [1], containing 0.1 to 70 parts by mass of the (meth)acrylic polymer (B) with respect to 100 parts by mass of the epoxy resin (A).

[3] The epoxy resin according to [1] or [2], wherein the absolute value of the difference between the SP value of the carboxyl group-containing (meth)acrylic polymer (B1) and the SP value of the epoxy compound (B2) is 1.3 to 4.5. composition.

[4] The epoxy resin composition according to any one of [1] to [3], wherein the (meth)acrylic polymer (B) has a weight average molecular weight of 3,000 to 100,000.

[5] The epoxy resin composition according to any one of [1] to [4], further comprising a curing agent (C).

[6] A cured resin comprising the epoxy resin composition according to the above [1] to [5].

[7] A resin obtained by curing an epoxy resin composition containing an epoxy resin and a (meth)acrylic polymer, having a sea-island phase separation structure, and having an average dispersion diameter of an island phase of 0.01 to 0.84 µm hardened material.

[8] The above-mentioned [7], wherein the tensile modulus of elasticity (X) of the cured resin product and the tensile modulus of elasticity (Y) of the cured resin product when the (meth)acrylic polymer is not included satisfy the following formula (2) resin cured product.

0.6≤X/Y≤1.1...(2)

ADVANTAGE OF THE INVENTION According to this invention, the resin hardened|cured material excellent in impact resistance can be provided by using the epoxy resin composition which mix|blended the specific (meth)acrylic polymer as a modifier with an epoxy resin.

(Form for implementing the invention)

Hereinafter, the present invention will be described in detail. In the present specification, (meth)acryl is used as a generic name of acryl and methacryl, acryl or methacryl may be used, (meth)acrylate is used as a generic name of acrylate and methacrylate, and acrylate or methacryl rate may be sufficient.

[Epoxy Resin Composition]

One embodiment (hereinafter also referred to as "the epoxy resin composition of this embodiment") of the epoxy resin composition of the present invention is an epoxy resin (A) having a solubility parameter (SP value) of 11 to 15 described below, respectively, and and SP values contain the (meth)acrylic polymer (B) of 9.5-11. Here, the (meth)acrylic polymer (B) is a reaction product of the carboxyl group-containing (meth)acrylic polymer (B1) and the epoxy compound (B2).

(solubility parameter ( SP value )))

The solubility parameter (SP value) is used, for example, as indicating the degree of whether polymers of different types dissolve or not. By making the difference between the SP value of the (meth)acrylic polymer (B) and the SP value of the epoxy resin (A) within an appropriate range, the average dispersion diameter of the island phase in the resin cured product having a sea-island separation structure described later is appropriately determined. Values tend to be controllable.

In addition, the SP values of the epoxy resin (A) in this specification, the (meth)acrylic polymer (B), the carboxyl group-containing (meth)acrylic polymer (B1), and the epoxy compound (B2) are Robert F. Fedors., " POLYMER ENGINEERING AND SCIENCE”, 1974, Vol. 14, No. 2, it can be calculated from the sum (ΔH) of the molar heat of evaporation (Δei) of the atomic groups and the sum (V) of the molar volume (Δvi) described in 2, p151 to 153.

<Epoxy resin (A)>

The epoxy resin composition of this embodiment contains an epoxy resin (A). However, from the epoxy resin (A), as a reaction product of the above-mentioned carboxyl group-containing (meth)acrylic polymer (B1) and the epoxy compound (B2), the polymer having an epoxy group is excluded.

As an epoxy resin (A), the epoxy compound whose number of epoxy groups in 1 molecule is two or more is mentioned, for example.

As an epoxy resin (A), for example,

Bisphenol-type epoxy resins, hydrogenated bisphenol-type epoxy resins, alkyl Substituted bisphenol type epoxy resin, alkylene oxide modified bisphenol type epoxy resin, biphenyl type epoxy resin, resorcinol type epoxy resin, sulfide type epoxy resin, diphenyl ether type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin Resin, phenol novolak type epoxy resin, orotocresol novolak type epoxy resin, dicyclopentadiene novolak type epoxy resin, biphenyl novolak type epoxy resin, naphthalenephenol novolak type epoxy resin, glycidylamine type epoxy resin Suzy;

Bisphenols such as bisphenol A, bisphenol E, bisphenol F, bisphenol S, bisphenol O, and bisphenol AD or diglycidyl ether of 4,4-dihydroxybiphenyl [wherein the bisphenol and the biphenyl are hydrogenated, may be present (e.g., hydrogenated bisphenol), may have an alkyl substituent (e.g., alkyl-substituted bisphenol), or may be modified with alkylene oxide such as ethylene oxide-modified or propylene oxide-modified (e.g., alkylene oxide-modified bisphenol)] , Ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, 1,8-octanediol diglycidyl Alkanes such as alkanediol diglycidyl ether such as ether, 1,10-decanediol diglycidyl ether, 2,2-dimethyl-1,3-propanediol diglycidyl ether, and glycerin diglycidyl ether Polyalkylene glycol diglycerides such as triol diglycidyl ether, diethylene glycol diglycidyl ether, triethylene glycol diglycidyl ether, tetraethylene glycol diglycidyl ether, and hexaethylene glycol diglycidyl ether Diglycidyl ether compounds, such as diglycidyl ether of alicyclic containing dimethanol, such as cidyl ether and 1, 4- cyclohexane dimethanol diglycidyl ether;

Glycerin triglycidyl ether, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N,N'-tetraglycidyl-m-xylylenediamine, N,N ,N',N'-tetraglycidylaminophenylmethane, triglycidyl isocyanurate, m-N,N-diglycidylaminophenylglycidyl ether, N,N-diglycidyltoluidine, N, N-diglycidylaniline, 3',4'-epoxycyclohexylmethyl3,4-epoxycyclohexanecarboxylate, ε-caprolactone-modified 3',4'-epoxycyclohexylmethyl3,4-epoxycyclo hexanecarboxylate;

can be heard

An epoxy resin (A) may be used individually by 1 type, and may use 2 or more types.

SP values of the epoxy resin (A) are 11 to 15, preferably 11 to 13.5. An SP value within the above range is preferable from the viewpoint that the epoxy resin (A) and the (meth)acrylic polymer (B) constitute an island-in-the-sea phase separation structure having an island phase having an appropriate size and average dispersion diameter.

The epoxy resin composition of this embodiment WHEREIN: The absolute value of the difference of the SP value of a (meth)acrylic polymer (B) and the SP value of an epoxy resin (A) is 0.1-3.3, Preferably it is 1.5-3.3. When the absolute value of the difference in SP values is within the above range, the island phase separation structure is likely to be formed after curing of the resin composition, and the average dispersion diameter of the island phase is suitable, and the impact resistance of the cured resin product tends to be further improved. have.

The absolute value of the difference between the SP value of the epoxy resin (A) and the SP value of the epoxy compound (B2) is preferably 0 to 2.7 from the viewpoint of forming a sea-island separation structure having an average dispersion diameter of an appropriate size. , more preferably 0 to 2.5. In one aspect, it is preferable that the value which subtracted the SP value of an epoxy compound (B2) from the SP value of an epoxy resin (A) is -2.7-1.2, More preferably, it is -2.5-1.1.

Although the epoxy equivalent of an epoxy resin (A) is not specifically limited, Preferably it is 100-3000 g/eq., More preferably, it is 100-1000 g/eq.

<(meth)acrylic polymer (B)>

The (meth)acrylic polymer (B) is a reaction product of a carboxyl group-containing (meth)acrylic polymer (B1) and an epoxy compound (B2), preferably a carboxyl group-containing (meth)acrylic polymer (B1) and an epoxy compound It is an adduct with (B2). That is, the (meth)acrylic polymer (B) is a compound having a structure represented by the following formula (1) by reacting the carboxyl group of the carboxyl group-containing (meth)acrylic polymer (B1) with the epoxy group of the epoxy compound (B2) desirable.

By using the (meth)acrylic polymer (B) as a modifier with respect to the epoxy resin (A), the cured resin obtained from the epoxy resin composition of the present embodiment exhibits high impact resistance compared to the case where the modifier is not used. Moreover, the said cured resin does not significantly change the elasticity modulus which an epoxy resin originally has, and the impact resistance is improved. Moreover, the epoxy resin composition of this embodiment shows high adhesiveness with respect to a to-be-metal adherend.

Although the reason why such an effect is expressed is not certain, it is thought that the suitable compatibility of an epoxy resin and a modifier is important since it forms the sea-island structure containing the island phase which has an average dispersion diameter of an appropriate size. By using the (meth)acrylic polymer (B), which is the reaction product, as a modifier for the epoxy resin (A), the SP value and the SP value difference between the two are in an appropriate range, so that they are properly compatible with each other, and the average of the appropriate size It is estimated that the impact resistance of the resin hardened|cured material obtained from an epoxy resin composition improved by formation of the sea-island structure containing the island phase which has a dispersed diameter.

≪ carboxyl group contain ( meta )Acrylic Polymer (B1)≫

The carboxyl group-containing (meth)acrylic polymer (B1) (hereinafter also referred to as "polymer (B1)") has a structural unit derived from a monomer having a carboxyl group.

Further, the monomer having a carboxyl group includes a compound formed by ring-opening an acid anhydride group-containing monomer by hydrolysis.

As a monomer which has a carboxy group, For example, carboxy group containing monomers other than carboxy group containing (meth)acrylate, such as (meth)acrylic acid, itaconic acid, a crotonic acid, a maleic acid, and a fumaric acid; (meth)acrylic acid β-carboxyethyl, (meth)acrylic acid 5-carboxypentyl, succinic acid mono(meth)acryloyloxyethyl ester, ω-carboxypolycaprolactone mono(meth)acrylate, p-carboxybenzyl (meth) and carboxyl group-containing (meth)acrylates such as acrylic acid ester.

Examples of the acid anhydride group-containing monomer include maleic anhydride, dodecenyl succinic anhydride, chlorendic anhydride, sebacic anhydride, phthalic anhydride, pyromellitic anhydride, trimellitic anhydride, cyclopentane/tetracarboxylic acid dihydrate. Water, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, tetramethylenemaleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, 5-(2, 5-dioxotetrahydroxyfuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride and methylnadic anhydride are mentioned. Among these, (meth)acrylic acid is preferable.

The ratio of the monomer having a carboxyl group in the polymerizable unsaturated group-containing monomer used to obtain the polymer (B1) is preferably 0.8 to 15% by mass, more preferably 1 to 10% by mass.

The polymer (B1) is preferably a polymer having a repeating structural unit derived from (meth)acrylic acid ester. Polymer (B1) in one aspect WHEREIN: Preferably 40 mass % or more of (meth)acrylic acid ester, More preferably, 50 mass % or more, More preferably, it contains a polymerizable unsaturated group containing 60 mass % or more. It is a polymer of monomers.

As (meth)acrylic acid ester, for example,

Methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, iso -Octyl (meth) acrylate, nonyl (meth) acrylate, iso- nonyl (meth) acrylate, decyl (meth) acrylate, iso-decyl (meth) acrylate, undeca (meth) acrylate, lauryl Alkyl (meth)acrylates such as (meth)acrylate, oleyl (meth)acrylate, n-stearyl (meth)acrylate, and iso-stearyl (meth)acrylate, especially an alkyl group having 1 to 20 carbon atoms having an alkyl (meth)acrylate;

Cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, etc. (meth)acrylate containing an alicyclic hydrocarbon group or an aromatic hydrocarbon group;

Methoxymethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, 3-ethoxypropyl (meth) alkoxyalkyl (meth)acrylates such as acrylate, 4-methoxybutyl (meth)acrylate, and 4-ethoxybutyl (meth)acrylate;

Methoxydiethylene glycol mono(meth)acrylate, methoxydipropylene glycol mono(meth)acrylate, ethoxytriethylene glycol mono(meth)acrylate, ethoxydiethylene glycol mono(meth)acrylate, methoxytriethylene glycol Alkoxy polyalkylene glycol mono(meth)acrylates, such as mono(meth)acrylate;

N,N-dialkylaminoalkyl (meth)acrylates such as N,N-dimethylaminoethyl (meth)acrylate and N,N-diethylaminoethyl (meth)acrylate;

2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl ( hydroxyalkyl (meth)acrylates such as meth)acrylate;

2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl ( hydroxy group-containing (meth)acrylates such as meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, and (4-hydroxymethylcyclohexyl)methyl acrylate;

can be heard

From the viewpoint of making the (meth)acrylic polymer (B) an appropriate SP value, the polymerizable unsaturated group-containing monomer used to obtain the polymer (B1) contains an alkyl (meth)acrylate, an alicyclic hydrocarbon group or an aromatic hydrocarbon group The total ratio of (meth)acrylate and alkoxyalkyl (meth)acrylate becomes like this. Preferably it is 30-99 mass %, More preferably, it is 70-99 mass %.

Polymer (B1) is a monomer having a carboxyl group and other monomers other than (meth)acrylic acid ester (a hydroxyl group-containing monomer, an amide group-containing monomer, a cyano group-containing monomer, a nitrogen-containing heterocyclic monomer, a styrene-based monomer and a vinyl ether-based monomer) You may have a structural unit derived from at least 1 sort(s) chosen from a monomer.

Examples of the hydroxyl group-containing monomer include vinyl alcohol, allyl alcohol, 2-hydroxyethyl vinyl ether, and 4-hydroxybutyl vinyl ether.

As an amide group containing monomer, For example, (meth)acrylamide; N-alkyl (meth)acrylamide, such as N-methyl (meth)acrylamide, N-propyl (meth)acrylamide, and N-hexyl (meth)acrylamide; N,N-dialkyl (meth)acrylamide, such as N,N- dimethyl (meth)acrylamide and N,N- dipropyl (meth)acrylamide, is mentioned.

As a cyano group containing monomer, (meth)acrylonitrile is mentioned, for example.

Examples of the nitrogen-based heterocyclic monomer include N-vinylpyrrolidone, N-vinylcaprolactam, and (meth)acryloylmorpholine.

As a styrene-type monomer, For example, styrene, (alpha)-methylstyrene; alkyl styrenes such as 4-methylstyrene, 3,5-diethylstyrene, trimethylstyrene, propylstyrene, butylstyrene, hexylstyrene, heptylstyrene, octylstyrene, and 3,5-dimethylstyrene; halogenated styrenes such as 4-fluorostyrene, 4-chlorostyrene, 4-bromostyrene, and 3,5-dibromostyrene; and functionalized styrenes such as 4-nitrostyrene, 4-acetylstyrene, and 4-methoxystyrene.

Examples of the vinyl ether-based monomer include vinyl acetate; and alkyl vinyl ethers such as methyl vinyl ether, n-propyl vinyl ether, and n-butyl vinyl ether.

The ratio of other monomers in the polymerizable unsaturated group containing monomer used in order to obtain a polymer (B1) is 20 mass % or less, Preferably it is 10 mass % or less.

≪Epoxy compound (B2)≫

As an epoxy compound (B2), the epoxy compound whose number of epoxy groups in 1 molecule is two or more is mentioned, for example.

As the epoxy compound (B2), for example,

Bisphenol-type epoxy resins, hydrogenated bisphenol-type epoxy resins, alkyl Substituted bisphenol type epoxy resin, alkylene oxide modified bisphenol type epoxy resin, biphenyl type epoxy resin, resorcinol type epoxy resin, sulfide type epoxy resin, diphenyl ether type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin Resin, phenol novolak type epoxy resin, orthocresol novolak type epoxy resin, dicyclopentadiene novolak type epoxy resin, biphenyl novolak type epoxy resin, naphthalenephenol novolak type epoxy resin, glycidylamine type epoxy resin ;

Bisphenols such as bisphenol A, bisphenol E, bisphenol F, bisphenol S, bisphenol O, and bisphenol AD, or diglycidyl ether of 4,4-dihydroxybiphenyl [wherein the bisphenol and the biphenyl are hydrogenated to may be present (e.g., hydrogenated bisphenol), may have an alkyl substituent (e.g., alkyl-substituted bisphenol), or may be modified with alkylene oxide such as ethylene oxide-modified or propylene oxide-modified (e.g., alkylene oxide-modified bisphenol)] , Ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, 1,8-octanediol diglycidyl Alkanes such as alkanediol diglycidyl ether such as ether, 1,10-decanediol diglycidyl ether, 2,2-dimethyl-1,3-propanediol diglycidyl ether, and glycerin diglycidyl ether Polyalkylene glycol diglycerides such as triol diglycidyl ether, diethylene glycol diglycidyl ether, triethylene glycol diglycidyl ether, tetraethylene glycol diglycidyl ether, and hexaethylene glycol diglycidyl ether Diglycidyl ether compounds, such as diglycidyl ether of alicyclic containing dimethanol, such as cidyl ether and 1, 4- cyclohexane dimethanol diglycidyl ether;

Glycerin triglycidyl ether, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-m-xylylenediamine, N, N,N',N'-tetraglycidylaminophenylmethane, triglycidyl isocyanurate, m-N,N-diglycidylaminophenylglycidyl ether, N,N-diglycidyltoluidine, N ,N-diglycidylaniline, 3',4'-epoxycyclohexylmethyl3,4-epoxycyclohexanecarboxylate, ε-caprolactone-modified 3',4'-epoxycyclohexylmethyl3,4-epoxy cyclohexanecarboxylate;

can be heard

Although the epoxy equivalent of an epoxy compound (B2) is not specifically limited, Preferably it is 100-3000 g/eq., More preferably, it is 100-1000 g/eq.

It is preferable that it is 9.0-11.5, and, as for the SP value of a carboxyl group containing (meth)acrylic polymer (B1), it is more preferable that it is 9.0-11. Moreover, it is preferable that SP values are 10-15, and, as for an epoxy compound (B2), 11-13.5 are more preferable.

The absolute value of the difference between the SP value of the carboxyl group-containing (meth)acrylic polymer (B1) and the SP value of the epoxy compound (B2) forms a sea-island separation structure having an island phase having an average dispersion diameter of an appropriate size. , Preferably it is 1.3-4.5, More preferably, it is 1.3-3.7. In one aspect, it is preferable that the value obtained by subtracting the SP value of the epoxy compound (B2) from the SP value of the carboxyl group-containing (meth)acrylic polymer (B1) is -4.5 to -1.3, more preferably -3.6 to -1.3 to be.

Among these epoxy compounds (B2), from the viewpoint of forming a sea-island separation structure with an appropriate size, a bisphenol type epoxy resin such as a bisphenol A type epoxy resin, bisphenol or diglycidyl of 4,4-dihydroxybiphenyl Polyalkylene glycol diglycols, such as ether [here, the said bisphenol and the said biphenyl may be hydrogenated, may have an alkyl substituent, and may be alkylene oxide modified|denatured], diethylene glycol diglycidyl ether, etc. Cidyl ether is preferred.

≪( meta ) Preparation of acrylic polymer (B)≫

A (meth)acrylic polymer (B) can be manufactured by a well-known method, and can be obtained by making a carboxy group containing (meth)acrylic polymer (B1) and an epoxy compound (B2) react.

Although the carboxyl group-containing (meth)acrylic polymer (B1) is not particularly limited, it is preferably produced by bulk polymerization from the viewpoint of removing impurities. Specifically, a polymerizable unsaturated group-containing monomer, a polymerization initiator, a chain transfer agent and a polymerization solvent are charged into the reaction vessel, and heated to a reaction temperature of about 50 to 150° C. in an atmosphere of an inert gas such as nitrogen gas, and 2 to 20 time react. Further, during the polymerization reaction, a polymerizable unsaturated group-containing monomer, a polymerization initiator, a chain transfer agent, and a polymerization solvent may be further added as appropriate.

As a polymerization initiator, a normal organic type polymerization initiator is mentioned, for example, Specifically, a peroxide compound and an azo compound are mentioned.

Examples of the peroxide compound include 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, t-amylperoxy-2- Ethylhexanoate, t-butylperoxy-2-ethylhexanoate, cumylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, t-hexylperoxyneo Decanoate, t-butylperoxyneodecanoate, t-butylperoxyneoheptanoate, t-hexylperoxypivalate, t-butylperoxypivalate, 2,5-dimethyl-2,5- di(2-ethylhexanoylperoxy)hexane, 2,5-dimethyl-2,5-di(2-benzoylperoxy)hexane, t-butylperoxy-3,5,5-trimethylhexanoate, t -Butyl peroxylaurate and t-hexyl peroxybenzoate are mentioned.

As the azo compound, for example, 2,2'-azobisisobutyronitrile, 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis (2-cyclopropylpropionitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2-methylbutyronitrile), 1,1'-azo Bis(cyclohexane-1-carbonitrile), 2-(carbamoylazo)isobutyronitrile, 2-phenylazo-4-methoxy-2,4-dimethylvaleronitrile, 2,2'-azobis (2-amidinopropane)dihydrochloride, 2,2'-azobis(N,N'-dimethyleneisobutylamidine), 2,2'-azobis[2-methyl-N-(2-) Hydroxyethyl)-propionamide], 2,2'-azobis(isobutylamide)dihydrate, 4,4'-azobis(4-cyanopentanoic acid), 2,2'-azobis(2-cya) nopropanol), dimethyl-2,2'-azobis(2-methylpropionate), and 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide]. .

A polymerization initiator may be used individually by 1 type, and may use 2 or more types.

The usage-amount of a polymerization initiator is 0.01-5 mass parts normally with respect to 100 mass parts of polymerizable unsaturated-group containing monomers. If it is such an aspect, the number average molecular weight (Mn) of a (meth)acrylic polymer (B) can be adjusted within an appropriate range.

When preparing the polymer (B1), it is preferable to polymerize the polymerizable unsaturated group-containing monomer in the presence of a chain transfer agent, and from the viewpoint of suppressing bubbles generated during curing of the epoxy resin, the residual of low molecular weight components such as residual monomer is suppressed In order to do this, it is more preferable to polymerize in the presence of a chain transfer agent having a highly reactive polar group.

As the chain transfer agent having a polar group in the molecule, a thiol-based chain transfer agent having a polar group in the molecule is preferable. Examples of the thiol-based chain transfer agent having a polar group in the molecule include a thiol-based chain transfer agent having one or more polar groups in the molecule, such as a carboxy group, a hydroxyl group, an amino group, and a sulfonic acid group. Among these polar groups, a carboxy group and a hydroxyl group are preferable. Examples of the thiol-based chain transfer agent having a polar group in such a molecule include carboxyl group-containing thiol compounds such as α-mercaptopropionic acid and β-mercaptopropionic acid; Hydroxy group-containing thiol compounds, such as 1-mercaptoethanol, 2-mercaptoethanol, and 1-mercaptopropanol, are mentioned. In addition, as a chain transfer agent, alkylthiol compounds, such as normal octyl mercaptan and a normal dodecyl mercaptan, are mentioned, for example.

One type or two or more types of chain transfer agents may be used.

To [ the usage-amount of a chain transfer agent / 100 mass parts of polymerizable unsaturated group containing monomers ], Preferably it is 0.1-10 mass parts, More preferably, it is 3-8 mass parts. If it is such an aspect, the weight average molecular weight and number average molecular weight of a (meth)acrylic polymer (B) can be adjusted to an appropriate range.

In solution polymerization, as a polymerization solvent, For example, aromatic hydrocarbons, such as benzene, toluene, and xylene; aliphatic hydrocarbons such as n-pentane, n-hexane, n-heptane, and n-octane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, cycloheptane and cyclooctane; ethers such as diethyl ether, diisopropyl ether, 1,2-dimethoxyethane, dibutyl ether, tetrahydrofuran, dioxane, anisole, phenylethyl ether, and diphenyl ether; halogenated hydrocarbons such as chloroform, carbon tetrachloride, 1,2-dichloroethane and chlorobenzene; esters such as ethyl acetate, propyl acetate, butyl acetate, and methyl propionate; ketones such as acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, and cyclohexanone; amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone; nitriles such as acetonitrile and benzonitrile; and sulfoxides such as dimethyl sulfoxide and sulfolane.

A polymerization solvent may be used individually by 1 type, and may use 2 or more types.

The (meth)acrylic polymer (B) is preferably 0.1 to 500 parts by mass, more preferably 5 to 300 parts by mass of the epoxy compound (B2) with respect to 100 parts by mass of the carboxyl group-containing (meth)acrylic polymer (B1). , More preferably, it is 10-200 mass parts, It is preferable that it is a polymer obtained by making it react more preferably in the range of 15-100 mass parts. The cured resin product containing the polymer obtained by reacting the epoxy compound (B2) within the above range forms a sea-island separation structure with an appropriate size, and is excellent in impact resistance. Moreover, when making a carboxyl group containing (meth)acrylic polymer (B1) and an epoxy compound (B2) react, you may use a well-known epoxy curing catalyst.

Further, in the (meth)acrylic polymer (B), the molar ratio (B1/B2) of the carboxyl group in the carboxyl group-containing (meth)acrylic polymer (B1) to the epoxy group in the epoxy compound (B2) is preferably 0.1 to 1, more preferably It is preferable that it is a polymer obtained by making it react in the range of 0.3-1.

≪( meta ) Content of Acrylic Polymer (B)≫

With respect to 100 mass parts of epoxy resins (A), as for the epoxy resin composition of this embodiment, Preferably the (meth)acrylic polymer (B) is 0.1-70 mass parts, More preferably, it is 10-70 mass parts, More preferably, Preferably, it contains 10-40 mass parts. If it is such an aspect, it is preferable from a viewpoint which can provide impact resistance, without impairing the original characteristic of an epoxy resin.

From the viewpoint of obtaining the excellent adhesive strength with the metal adherend, the epoxy resin composition of the present embodiment contains the epoxy resin (A) and the (meth)acrylic polymer (B) in a total of 30% by mass or more in 100% by mass of the solid content. It is preferable to contain, More preferably, it is 50 mass % or more, More preferably, it contains 70 mass % or more. Solid content refers to components other than the solvent mentioned later.

≪( meta )Physical properties of acrylic polymer (B)≫

SP values of (meth)acrylic polymer (B) are 9.5-11, Preferably it is 9.7-10.7. An SP value within the above range is preferable from the viewpoint that the epoxy resin (A) and the (meth)acrylic polymer (B) constitute an island-in-the-sea phase separation structure having an island phase having an appropriate size and average dispersion diameter.

Although the epoxy equivalent of (meth)acrylic polymer (B) is not specifically limited, Preferably it is 100-10,000 g/eq., More preferably, it is 500-8,000 g/eq. It is preferable from a viewpoint of being excellent in the compatibility of an epoxy resin and a (meth)acrylic polymer (B) as it being the SP value within the said range.

The weight average molecular weight (Mw) of (meth)acrylic polymer (B) becomes like this. Preferably it is 3,000-100,000, More preferably, it is 3,500-80,000.

Moreover, Preferably the number average molecular weights (Mn) of a (meth)acrylic polymer (B) are 1,500-15,000, More preferably, it is 1,500-8,000. When the molecular weight satisfies these conditions, the (meth)acrylic polymer (B) has an appropriate viscosity, is excellent in handling properties, and is preferable in terms of compatibility with the epoxy resin (A) and durability of the resulting cured resin. The weight average molecular weight (Mw) and the number average molecular weight (Mn) are measured by a gel permeation chromatography (GPC) method. The details of the measurement conditions of the GPC method are described in Examples to be described later.

The viscosity of the (meth)acrylic polymer (B) measured using an E-type viscometer under conditions at a liquid temperature of 25°C and a rotational speed of 6 rpm is preferably 150 Pa·s or less, more preferably 100 Pa·s or less. Although the lower limit of the said viscosity is not specifically limited, In one aspect, it is 1 Pa*s.

<curing agent (C)>

It is preferable that the epoxy resin composition of this embodiment contains a hardening|curing agent (C) with an epoxy resin (A) and a (meth)acrylic polymer (B). A hardening|curing agent (C) is a compound which hardens an epoxy resin composition by reacting with an epoxy resin (A), for example.

As a hardening|curing agent (C), polyamine, polycarboxylic acid, acid anhydride, and phenol are mentioned, for example, In addition, imidazole, polymercaptans, and organic acid hydrazide are mentioned.

Examples of the polyamine include diethylenetriamine, dipropylenetriamine, triethylenetetramine, tetraethylenepentamine, dimethylaminopropylamine, diethylaminopropylamine, dibutylaminopropylamine, hexamethylenediamine, and trimethylhexa. aliphatic polyamines such as methylenediamine, bis-(hexamethylene)triamine, and polyoxypropylenediamine; 3,3'-Dimethyl-4,4'-diaminodicyclohexylmethane, 3-amino-1-cyclohexylaminopropane, 4,4'-diaminodicyclohexylmethane, isophoronediamine, 1,3- alicyclic polyamines such as bis(aminomethyl)cyclohexane and a mixture of N-dimethylcyclohexylaminopropane and 4,4'-diaminodicyclohexylaminopropane; 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, diaminodiphenylsulfone, m-phenylenediamine, 2,4-toluylenediamine, 2,6-toluylenediamine, aromatic polyamines such as 2,3-toluylenediamine, 3,4-toluylenediamine, metaxylylenediamine, and xylylenediamine; heterocyclic polyamines such as N-aminoethylpiperazine; amide-based curing agents such as dicyandiamide and diacetone acrylamide; These modified products (for example, an epoxy adduct, an acrylonitrile adduct, an ethylene oxide adduct, a Mannich reaction product, a Michael reaction product, a thiourea reaction product, modified aromatic amine) are mentioned.

Examples of the polycarboxylic acid include phthalic acid, hydroxyisophthalic acid, succinic acid, sebacic acid, maleic acid, dodecenylsuccinic acid, chlorendic acid, pyromellitic acid, trimellitic acid, hexahydrophthalic acid, methylhexahydrophthalic acid, Tetrahydrophthalic acid, methyltetrahydrophthalic acid, and methylnadic acid are mentioned.

As acid anhydride, for example, maleic anhydride, dodecenyl succinic anhydride, chlorendic anhydride, sebacic anhydride, phthalic anhydride, pyromellitic anhydride, trimellitic anhydride, cyclopentane tetracarboxylic dianhydride, hexa Hydrophthalic anhydride, methylhexahydrophthalic anhydride, tetramethylene maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, 5-(2,5-di and oxotetrahydroxyfuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride and methylnadic anhydride.

Examples of the phenols include bisphenol A, bisphenol F, bisphenol S, bisphenol AD, hydroquinone, resorcin, methylresorcin, biphenol, tetramethylbiphenol, dihydroxynaphthalene, dihydroxydiphenyl ether, thi Odiphenol, phenol novolak resin, cresol novolak resin, phenol aralkyl resin, biphenyl aralkyl resin, naphthol aralkyl resin, terpene phenol resin, dicyclopentadiene phenol resin, bisphenol A novolak resin, triphenol methane type Polyhydric phenols such as resins, naphthol novolac resins, brominated bisphenol A and brominated phenol novolac resins, and polyhydric phenols obtained from the condensation reaction of various phenols with various aldehydes such as benzaldehyde, hydroxybenzaldehyde, crotonaldehyde, and glyoxazal Phenolic resins, polyhydric phenol resins obtained from the condensation reaction of xylene resins with phenols, co-condensation resins of heavy oil or pitches with phenols and formaldehydes, polycondensates of phenol benzaldehyde xylylene dimethoxide, phenol benzaldehyde - Various phenol resins, such as a xylylene dihalide polycondensation product, a phenol benzaldehyde 4,4'- dimethoxide biphenyl polycondensation product, and a phenol benzaldehyde 4,4'- dihalide biphenyl polycondensate, are mentioned. .

Examples of the imidazoles include 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, and 1-benzyl-2- Phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1- Cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-dia Mino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-( 1')]-ethyl-s-triazineisocyanuric acid adduct, 2-phenylimidazoleisocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl- 4-methyl-5-hydroxymethylimidazole is mentioned.

Among these curing agents (C), in one aspect, polyamines, amide curing agents, and imidazoles are preferable, and aliphatic polyamines and modified products of aliphatic polyamines are more preferable.

A hardening|curing agent (C) may be used individually by 1 type, and may use 2 or more types.

The epoxy resin composition of this embodiment, in one aspect, in an equivalent ratio to the epoxy resin (A), the curing agent (C) is preferably 0.01 to 10 equivalents, more preferably 0.1 to 5 equivalents, still more preferably contains 0.5 to 2 equivalents. If it is such an aspect, it is preferable from a sclerosis|hardenability viewpoint.

<Cation or anion polymerization initiator >

The epoxy resin composition of this embodiment may contain a cationic or anionic polymerization initiator instead of a hardening|curing agent (C) or with a hardening|curing agent (C). The cationic or anionic polymerization initiator is a compound that initiates and/or accelerates the curing reaction of the epoxy resin (A) by heating or light.

What is necessary is just to generate|occur|produce cationic species, such as a Bronsted acid and a Lewis acid, by heating or light as a cationic polymerization initiator, For example, an onium salt, a protonic acid ester, and a Lewis acid-amine complex are mentioned. A cationic polymerization initiator may be used individually by 1 type, and may use 2 or more types.

As an anionic polymerization initiator, what is necessary is just to generate|occur|produce anionic species, such as a Bronsted base and a Lewis base, by heating or light, For example, imidazole and tertiary amines are mentioned. Anionic polymerization initiators may be used individually by 1 type, and may use 2 or more types.

In one aspect, the epoxy resin composition of this embodiment preferably contains 0.001-50 mass parts of cationic or anionic polymerization initiators with respect to 100 mass parts of epoxy resins (A), More preferably, 0.01-30 mass parts It is a mass part, More preferably, it contains 0.1-10 mass parts. If it is such an aspect, it is preferable from a sclerosis|hardenability viewpoint.

<Additives>

The epoxy resin composition of the present embodiment, if necessary, a UV absorber, antioxidant, preservative, rust preventive, pigment, tackifier, surface lubricant, brightener, water repellent, photosensitizer, organic/inorganic fiber, plasticizer, conductive filler, inorganic filler , a flame retardant, an antistatic agent, a foam stabilizer, a mold release agent, a colorant and at least one additive selected from a foaming agent. An additive may be used individually by 1 type, and may use 2 or more types.

<solvent>

The epoxy resin composition of this embodiment may contain a solvent. Examples of the solvent include the solvent listed as the polymerization solvent in the method for producing the (meth)acrylic polymer (B), or a reactive diluent such as an epoxy compound having one epoxy group in one molecule.

A solvent may be used individually by 1 type, and may use 2 or more types.

The content rate of the solvent in the epoxy resin composition of this embodiment is 70 mass % or less normally, Preferably it is 30 mass % or less, More preferably, it is 20 mass % or less.

[Use of epoxy resin composition]

By using the epoxy resin composition of this embodiment, the cured resin material which has sufficient elastic modulus and impact resistance can be formed.

Since the epoxy resin composition of this embodiment has the said characteristic, it can be used for uses, such as an electronic material, a binder, a paint, an adhesive agent, for example. Specifically, substrate substrates for electronic components such as semiconductor packages, build-up films, solder resist inks, underfill materials, solid sealing materials for packages, packaging binders, binders for carbon fiber reinforced plastics (CFRP), cationic electrodeposition coating agents, Examples include heavy-duty coatings, powder coatings, adhesives for infrastructure repair/reinforcement, and general household/industrial adhesives. The epoxy resin composition of this embodiment is suitable for those uses.

[Suzy cured product ]

One embodiment of the cured resin of the present invention (hereinafter, also referred to as "the cured resin of this embodiment") is obtained by curing the epoxy resin composition of the present embodiment.

The cured resin of the present embodiment preferably has a sea-island separation structure.

In addition, the said sea-island phase separation structure is a structure in which the component derived from the (meth)acrylic polymer (B) as an island phase (dispersed phase) is dispersed in the component derived from the epoxy resin (A) as a sea phase (continuous phase). desirable.

In the sea-island phase separation structure of the cured resin product of the present embodiment, the average dispersion diameter of the island phase is preferably 0.01 to 0.84 µm, more preferably 0.03 to 0.80 µm. When the average dispersion diameter of the island phase is within the above range, the impact resistance of the cured resin can be improved while maintaining the original elastic modulus of the epoxy resin. When the average dispersed diameter of the island phase is less than 0.01 µm or more than 0.84 µm, there is a tendency for a decrease in the original elastic modulus of the epoxy resin to be seen.

When the cured resin obtained by curing the epoxy resin composition of the present embodiment has a sea-island separation structure, for example, the cured resin obtained is cut using a razor blade or a microtome, and the cut surface is subjected to a transmission electron microscope or a scanning type. It can be confirmed by observing using an electron microscope, an atomic force microscope, etc.

The tensile modulus of elasticity (X) of the cured resin of the present embodiment and the tensile modulus of elasticity (Y) of the cured resin in the case where the (meth)acrylic polymer (B) of the present embodiment is not satisfied is that the following formula (2) is satisfied desirable.

0.6≤X/Y≤1.1...(2)

It is preferable that it is 0.7 or more, as for the lower limit of Formula (2), It is more preferable that it is 0.75 or more, It is more preferable that it is 0.8 or more. As for the upper limit of Formula (2), it is more preferable that it is 1.08 or less, and it is still more preferable that it is 1.05 or less.

In a curable composition made of an epoxy resin, when a modifier is blended to improve impact resistance, the original elastic modulus of the epoxy resin changes.

In the cured resin of this embodiment, even when the modifier ((meth)acrylic polymer (B)) is blended, since the above formula (2) is satisfied, the impact resistance can be improved without readjusting the elastic modulus of the cured product. can

As a method of hardening the epoxy resin composition of this embodiment, after mixing each component and preparing the epoxy resin composition of this embodiment, for example, the method of performing hardening reaction by heating or light is mentioned.

The said mixing is performed using, for example, a mixer, a blender, and a roll.

In the case of thermosetting, the heating temperature (curing temperature) at the time of hardening is usually 20-300 degreeC, Preferably it is 40-250 degreeC, More preferably, it is 60-200 degreeC. Moreover, the heating time (curing time) at the time of hardening is 10-1440 minutes normally, Preferably it is 30-900 minutes, More preferably, it is 60-480 minutes. The heating may be performed in multiple stages.

In the case of photocuring, light, such as an ultraviolet-ray, a visible light, and infrared rays, is mentioned, and an ultraviolet-ray is preferable. The exposure amount is preferably from 1 to 10000 mJ/cm ² , more preferably from 10 to 3000 mJ/cm ² . Examples of the light source include a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, a chemical lamp, a black light fluorescent lamp, and an electrodeless UV lamp.

The said hardening reaction may apply|coat and perform the epoxy resin composition of this embodiment on a board|substrate, and may also inject|pour into a mold and may perform it.

The shape of the cured resin material of the present embodiment is not particularly limited, and examples thereof include a plate shape, a sheet shape, and a film shape. These thicknesses are, for example, usually 0.01 to 1000 mm, and preferably 0.1 to 100 mm.

Another embodiment of the cured resin product of the present invention is obtained by curing an epoxy resin composition containing an epoxy resin and a (meth)acrylic polymer, has a sea-island separation structure, and has an average dispersion diameter of the island phase from 0.01 to 0.84 It is a resin hardened|cured material of micrometer. Here, it is preferable to use the epoxy resin composition of this embodiment mentioned above as an epoxy resin composition containing an epoxy resin and a (meth)acrylic polymer.

It is preferable that the tensile modulus of elasticity (X) of the cured resin of the other embodiment and the tensile modulus of elasticity (Y) of the cured resin in the case of not containing the (meth)acrylic polymer satisfy the following formula (2).

0.6≤X/Y≤1.1...(2)

It is preferable that it is 0.7 or more, as for the lower limit of Formula (2), It is more preferable that it is 0.75 or more, It is more preferable that it is 0.8 or more. As for the upper limit of Formula (2), it is more preferable that it is 1.08 or less, and it is still more preferable that it is 1.05 or less.

Example

Hereinafter, the present invention will be described more specifically based on Examples, but the present invention is not limited to these Examples. In the description of Examples and the like, “parts” means “parts by mass” unless otherwise specified.

< SP value >

The SP value of each component is the sum (ΔH) and the molar volume ( It was calculated from the sum (V) of (DELTA)vi).

<weight average molecular weight (Mw); number average Molecular Weight (Mn)>

The weight average molecular weight (Mw) and number average molecular weight (Mn) of the polymer were analyzed by a gel permeation chromatography (GPC) method, and were calculated in terms of polystyrene under the following conditions.

・Device: GPC-8220 (made by Toso)

・Column: G7000HXL/7.8mmID × 1 +

GMHXL/7.8mmID×2 +

G2500HXL/7.8mmID×1

Medium: tetrahydrofuran

·Flow rate: 1.0mL/min

Concentration: 1.5mg/mL

・Injection amount: 300μL

·Column temperature: 40℃

<Viscosity>

The viscosity of each polymer was measured using the E-type viscometer VISCONIC EHD type (made by Tokyo Keiki) on the conditions in liquid temperature 25 degreeC and rotation speed 6rpm.

<epoxy equivalent weight >

The epoxy equivalent of the polymer was calculated|required based on JISK7236.

[ production example One]

To a flask equipped with a stirring device, nitrogen gas introduction tube, thermometer and reflux cooling tube, 62.1 parts of 2-ethylhexyl acrylate, 2.5 parts of acrylic acid, and 4.3 parts of β-mercaptopropionic acid were added, and nitrogen gas was introduced into the flask for 30 minutes. After stirring and nitrogen substitution, the temperature of the contents of the flask was raised to 60°C. Then, 0.06 parts of azobisisobutyronitrile was added while maintaining the contents in the flask at 60°C, and the reaction was started. Then, after adding and reacting 0.06 parts of azobisisobutyronitrile 6 times every hour, it is made to react at 100 degreeC - 125 degreeC for 3 hours, the volatile component in the product is distilled off under reduced pressure, and a carboxyl group-containing (meth)acrylic polymer (B1-1) was obtained. Next, in the flask, 31.1 parts of a bisphenol A epoxy resin ("jER828", manufactured by Mitsubishi Chemical, SP value = 12.8) as an epoxy compound (B2) and an epoxy curing catalyst (triphenylphosphine, "Hokuko TPP", Hoku Coca-Chem) was charged in an appropriate amount, and the mixture was stirred at 110°C for 8 hours. Then, the (meth)acrylic polymer (B-1) was obtained by cooling to room temperature. The (meth)acrylic polymer (B-1) had an SP value of 10.2, Mw of 5814, Mn of 3342, a viscosity of 40.2 Pa·s, and an epoxy equivalent of 2316 g/eq.

[ production example 2~15, 20, 21]

Except having changed into the composition shown in Table 1, (meth)acrylic polymers (B-2) - (B-15), (cB-5), (cB-6) were obtained by the method similar to manufacture example 1. Table 1 shows the SP value, Mw, Mn, viscosity, and epoxy equivalent of each polymer.

[ production example 16]

Into a flask equipped with a stirring device, nitrogen gas introduction tube, thermometer, and reflux cooling tube, 100 parts of methyl ethyl ketone was charged, 92 parts of 2-ethylhexyl acrylate, 6 parts of glycidyl methacrylate, and n-dodecyl mercaptan After adding 2 parts and performing nitrogen substitution by stirring for 30 minutes, introduce|transducing nitrogen gas in the flask, the content of the flask was heated up to 60 degreeC. Then, 0.2 parts of azobisisobutyronitrile was added while maintaining the contents in the flask at 60°C, and the reaction was started. After reaction for 3 hours, 0.2 parts of azobisisobutyronitrile was further added, and it was made to react at 75-80 degreeC after that for 5 hours, and the epoxy-group containing (meth)acrylic polymer (cB-1) was obtained. The (meth)acrylic polymer (cB-1) had an SP value of 9.4, Mw of 14588, Mn of 7521, a viscosity of 42.1 Pa·s, and an epoxy equivalent of 1872 g/eq.

[ production example 17-19]

Except having changed to the composition shown in Table 1, reaction was performed on the same conditions as manufacture example 16, and epoxy-group containing (meth)acrylic polymer (cB-2), (cB-3), and (cB-4) were obtained, respectively. SP value, molecular weight, viscosity, and epoxy equivalent are as showing in Table 1.

[Table 1]

(※ 1) In Table 1, in the case of (meth)acrylic polymers (cB-1) to (cB-4), it is a polymer using an epoxy group-containing (meth)acrylate as a contrast, not the B1 component and B2 component, For convenience, they are also described in the column of "B1".

The meaning of the abbreviation of each monomer, a chain transfer agent, and an epoxy compound is as follows.

BA: n-butyl acrylate

·2EHA: 2-ethylhexyl acrylate

GMA: glycidyl methacrylate

AA: acrylic acid

MAA: methacrylic acid

BMPA: β-mercaptopropionic acid

· NOM: n-octyl mercaptan

NDM: n-dodecyl mercaptan

· jER828: Bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical)

・Eporite 100E: diethylene glycol diglycidyl ether (manufactured by Kyoe Shisha Chemical)

Eporite 3002N: bisphenol A PO (propylene oxide) 2 mol adduct diglycidyl ether (manufactured by Kyoe Shisha Chemical)

These SP values were described in Table 1.

[ Example One]

Bisphenol A type epoxy resin (trade name "jER828", manufactured by Mitsubishi Chemical) 100 parts, (meth)acrylic polymer (B-1) 40 parts, aliphatic polyamine hardener (trade name "ST12", manufactured by Mitsubishi Chemical) 50 parts rotation and revolution It mixed with a mixer (product name "Awatori Rentaro", made by Shinki) to obtain an epoxy resin composition.

[ Example 2-18, comparative example 1 to 6, Reference example 1-3]

Except having changed into the compounding composition described in Table 2-1 and Table 2-2 (Hereinafter, these are put together and it is also called "Table 2"), it carried out similarly to Example 1, and obtained the epoxy resin composition. The composition conditions are described in Table 2 together with the evaluation results. In Table 2, "113" is jRE Cure 113 (modified alicyclic amine, manufactured by Mitsubishi Chemical), "DICY15" is jER Cure DICY15 (micronized dicyandiamide, manufactured by Mitsubishi Chemical), "2E4MZ" is Qazole 2E4MZ ( imidazole, manufactured by Shikoku Kasei Kogyo Co., Ltd.).

[Table 2-1]

[Table 2-2]

(*2) In Table 2, in the case of Comparative Examples 1 to 4, the polymers (cB-1) to (cB-4) using an epoxy group-containing (meth)acrylate as a contrast rather than the B1 component and B2 component. The SP value was also described as the SP value of "component (B)" for convenience. Similarly, the SP value "absolute value of the difference between (A) component and (B) component" in Comparative Examples 1 to 4 is calculated based on the SP values of (cB-1) to (cB-4). did.

[evaluation]

< dumbbell Tensile Modulus of Modulus of Specimen>

The epoxy resin compositions obtained in Examples, Comparative Examples and Reference Examples were poured into a SUS mold, and Examples 1 to 13, Reference Examples 1 and 2, and Comparative Examples 1 to 6 were cured at 80° C. for 3 hours, and Example 14 About 18 and Reference Example 3, it hardened at 150 degreeC for 1 hour, and produced the dumbbell test piece. The tensile modulus of elasticity was measured under the following conditions based on JIS-K7161.

・Sample size: Dumbbell size 1A

·Test speed: 10mm/min

Measurement environment: temperature 23℃, humidity 50% RH

・Number of measurements: measured three times and calculated as an average value

In addition, based on the tensile modulus of elasticity (X) of the dumbbell test pieces obtained in Examples and Comparative Examples and the tensile modulus of elasticity (Y) of the cured resin of Reference Examples 1 or 2, the tensile modulus as an index of change in the elastic modulus of the curable composition containing the modifier The ratio of the tensile modulus (X) to the modulus of elasticity (Y) (tensile modulus (X)/tensile modulus (Y)) was calculated. In addition, in each Example and a comparative example, the compounding composition of an epoxy resin (A) and a hardening|curing agent (C) was based on the same reference example.

<Shear adhesive strength>

In accordance with JIS-K6850, the epoxy resin composition obtained in each Example, Comparative Example and Reference Example was applied to a thickness of 0.2 mm so that the ends of each of the two test pieces (SUS plates or Fe plates) overlap each other by 12.5 mm. was applied, and the layer of the resin composition was sandwiched with a test piece and overlapped, and for Examples 1 to 13, Reference Examples 1 and 2, and Comparative Examples 1 to 6, dried at 80° C. for 3 hours, Examples 14 to 18, Reference About Example 3, it dried at 150 degreeC for 1 hour, and obtained the adhesion test piece for evaluation fixed with the epoxy resin composition.

A tensile shear adhesion test was performed using the adhesion test piece for evaluation. As the tensile tester, Shimadzu's universal tensile tester AG-X was used.

・Sample size: Conforms to JIS-K6850

·Test speed: 200mm/min

Measurement environment: temperature 23℃, humidity 50% RH

・Measured value: measured three times and calculated as an average value

<Average variance on the map diameter >

The sea-island structure was observed at the fracture surface of the test piece fractured in the tensile modulus test of the dumbbell test piece at a magnification of 10,000 times using SEM (product name "S-4800", manufactured by Hitachi High-Technologies). The observed SEM image was analyzed using the average particle diameter analysis software (product name "Fine-View", manufactured by Astron), and the ferret diameter of the island phase (dispersed phase) in the acquired SEM image (9.2 µm × 12.7 µm) was measured. did. Specifically, the island phase (dispersed phase) was sandwiched between parallel lines in a certain direction, and the distance between the parallel lines was measured. The number average value of the measured ferret diameter of the island was taken as the average dispersed diameter of the island.

< hardened Adhesiveness>

After the dumbbell test piece was left still on the PET film at 25 ° C. 50% RH for 24 hours, the PET film of the dumbbell test piece, the installed surface, and the PET film of the portion where the dumbbell test piece was placed were visually checked, and the following It was evaluated according to the evaluation criteria.

AA: There is no change in the appearance of the surface of the test piece, and no transfer is observed on the PET film.

BB: Bleeding material to the PET film is confirmed from the partial surface of the test piece surface.

CC: From the entire surface of the test piece surface, the bleeding material to the PET film is confirmed.

<Impact resistance test>

In accordance with JIS-K6850, the epoxy resin composition obtained in each Example, Comparative Example and Reference Example was applied to the test piece with a thickness of 0.2 mm so that each end of the two test pieces overlapped by 12.5 mm, and a layer of the resin composition was applied to the test piece. For example 1 to 13, Reference Examples 1 and 2, and Comparative Examples 1 to 6, dried at 80° C. for 3 hours, and for Examples 14 to 18 and Reference Example 3, dried at 150° C. for 1 hour. to obtain an adhesion test piece for evaluation immobilized with the epoxy resin composition.

The drop impact test was done using the said adhesion test piece for evaluation. As the type of test, the DuPont type was adopted. The test piece was installed so that the distance from the pedestal to the adhesive layer of the epoxy resin composition might be set to 50 mm, the height of 1 kg was changed between 10-30 cm in height, every 10 cm, and it was dropped on the adhesion test piece for evaluation. It was confirmed whether the adhesive surface was destroyed, and the impact resistance was evaluated according to the following evaluation criteria according to the height of the weight.

AA: Not destroyed even at 30cm.

BB: Not destroyed at 20cm, but destroyed at 30cm.

CC: Not destroyed at 10cm, but destroyed at 20cm.

DD: Destroyed at a height of 10 cm.

<Consideration>

Comparative Examples 1 to 4 use an epoxy group-containing (meth)acrylic polymer as a modifier for the epoxy resin. In these epoxy-group containing (meth)acrylic polymers, the epoxy group is introduce|transduced in a polymer by using glycidyl methacrylate as a monomer component. These are not polymers obtained by making a carboxyl group-containing (meth)acrylic polymer and an epoxy compound react. In Comparative Examples 1-4, the impact resistance of the cured resin obtained did not fully improve.

In Comparative Examples 5 and 6, a polymer obtained by reacting a carboxyl group-containing (meth)acrylic polymer with an epoxy compound is used as a modifier for the epoxy resin. However, since the SP value was as low as 9.4 or as high as 11.8, the impact resistance of the resulting cured resin product was not sufficiently improved.

In contrast, in Examples, a polymer having an SP value in a specific range, obtained by reacting a carboxyl group-containing (meth)acrylic polymer with an epoxy compound, is used as a modifier for the epoxy resin. Moreover, the difference of the SP value of an epoxy resin and a modifier also exists in a specific range. In Examples, a cured resin product having excellent impact resistance was obtained.

Claims (8)

An epoxy resin (A) having a solubility parameter (SP value) of 11 to 15;
An epoxy resin composition containing a (meth)acrylic polymer (B) having an SP value of 9.5 to 11,
The (meth)acrylic polymer (B) is a reaction product of a carboxyl group-containing (meth)acrylic polymer (B1) and an epoxy compound (B2),
The epoxy resin composition whose absolute value of the difference of the SP value of the said (meth)acrylic polymer (B) and the SP value of the said epoxy resin (A) is 0.1-3.3. The method of claim 1,
The epoxy resin composition containing 0.1-70 mass parts of said (meth)acrylic polymer (B) with respect to 100 mass parts of said epoxy resins (A). 3. The method of claim 1 or 2,
The epoxy resin composition whose absolute value of the difference of the SP value of the said carboxyl group-containing (meth)acrylic polymer (B1) and the SP value of the said epoxy compound (B2) is 1.3-4.5. 4. The method according to any one of claims 1 to 3,
An epoxy resin composition having a weight average molecular weight of 3,000 to 100,000 of the (meth)acrylic polymer (B). 5. The method according to any one of claims 1 to 4,
The epoxy resin composition further containing a hardening|curing agent (C). A cured resin comprising the epoxy resin composition according to any one of claims 1 to 5. A cured resin obtained by curing an epoxy resin composition containing an epoxy resin and a (meth)acrylic polymer, having a sea-island separation structure, and having an island phase average dispersion diameter of 0.01 to 0.84 µm. 8. The method of claim 7,
A cured resin in which the tensile modulus of elasticity (X) of the cured resin material and the tensile modulus of elasticity (Y) of the cured resin material in the case where the (meth)acrylic polymer is not contained satisfy the following formula (2).
0.6≤X/Y≤1.1...(2)