JP2024011763A - Epoxy resin composition, curable resin composition, cured product of curable resin composition, adhesive structure, and adhesive imparting agent - Google Patents

Abstract

To provide an epoxy resin composition that is difficult to secure low temperature adhesion, which is excellent in low temperature adhesion.SOLUTION: An epoxy resin composition contains (A) an epoxy compound, (B) an adhesive auxiliary agent, and (C) epoxy-modified silicone in which an organic group containing an epoxy group is bonded to any terminal of linear silicone including a D unit.SELECTED DRAWING: None

Description

The present invention relates to containing epoxy-modified silicones. The present invention also relates to an adhesive agent made of epoxy-modified silicone.

Epoxy resins are used for a wide range of applications such as semiconductor encapsulation, structural materials, various adhesives, and paints by preparing and curing epoxy resin compositions containing other organic or inorganic fillers. For these applications, from the viewpoint of the usage environment, there is an increasing demand for temperature and humidity resistance such as cold resistance, heat resistance, and heat and humidity resistance, as well as weather resistance including light resistance.

In particular, for adhesion applications, when bonding dissimilar materials due to the recent shift to multi-materials, we aim to reduce strain caused by the differences in thermal properties of the materials that make up the dissimilar materials, as well as achieve adhesive strength that can be satisfied at low temperatures. Providing adhesive properties is becoming increasingly important. However, although epoxy resins are generally cured during practical use, the cured product is hard and brittle, making it difficult to ensure sufficient adhesive strength, especially at low temperatures. Therefore, adhesive strength is generally provided using an epoxy resin composition to which an organic elastomer such as a carboxyl-terminated butadiene acrylonitrile elastomer or a rubber having a core-shell structure is added.

From the viewpoint of polymer design, the structure necessary to ensure low-temperature adhesion is such that molecular motion does not freeze even at low temperatures, and from that perspective, the organic elastomers and rubbers mentioned above , low-temperature adhesion cannot be said to be sufficient because the motion may be frozen depending on the degree of low temperature. Therefore, attention has been paid to silicone structures represented by dimethylsiloxane (see Patent Document 1).

JP2017-008145

Patent Document 1 attempts to ensure heat resistance and adhesiveness by using various silicone structures such as silsesquioxane, but does not mention adhesiveness at low temperatures. Generally speaking, the more silicone compounds have a structure that ensures mobility at low temperatures, the lower their surface energy becomes, making it difficult to secure the necessary adhesive strength. In general, it is rarely applied to adhesives.

The present invention has been made in view of the problems of the prior art described above. That is, an object of the present invention is to provide an epoxy resin composition that has excellent low-temperature adhesion in an epoxy resin composition in which it is difficult to ensure low-temperature adhesion.

As a result of intensive studies to solve the above problems, the present inventors found that in epoxy resin compositions in which low-temperature adhesion is difficult to secure, the excellent low-temperature properties unique to silicone compounds can be achieved while ensuring the surface energy necessary for adhesion. By using an epoxy-modified silicone compound in which an organic group containing an epoxy group is bonded to the end of a chain silicone structure containing a D unit so that it can be incorporated into an epoxy resin, low-temperature adhesion properties can be specifically improved. This discovery led to the completion of the invention.
That is, the gist of the present invention resides in the following [1] to [16].

（式（１）中、ｍは１以上の整数を表す。ｎはそれぞれ１以上の整数を表す。Ｒ^１及びＲ^２は、それぞれ独立して、アルキル基又は芳香族基を表す。また、Ｒ^３及びＲ^４は、それぞれ独立して、ヒドロキシフェニル基、カルビノール基、カルボキシ基、アミノ基、及びメルカプト基からなる群から選ばれるエポキシ反応性官能基に由来する連結基を表す。）［４］前記Ｒ^１及びＲ^２は、メチル基である、［３］に記載のエポキシ樹脂組成物。
［５］前記（Ｂ）接着助剤が、カルボキシ基、ヒドロキシフェニル基、カルビノール基、アミノ基及びメルカプト基からなる群から選ばれる１種以上の末端基を有するブタジエンニトリルゴム及び／又はブタジエンゴムを含む、［１］～［４］のいずれかに記載のエポキシ樹脂組成物。
［６］前記（Ｃ）エポキシ変性シリコーンのエポキシ当量が１５００～５０００ｇ／当量の範囲である、［１］～［５］のいずれかに記載のエポキシ樹脂組成物。
［７］前記（Ａ）エポキシ化合物１００質量部に対して、前記（Ｃ）エポキシ変性シリコーンを２～２０質量部含有する、［１］～［６］のいずれかに記載のエポキシ樹脂組成物。
［８］更に、カップリング剤、難燃性剤、酸化防止剤、光安定剤、可塑剤、反応希釈剤、顔料、無機充填材及び有機充填材からなる群から選ばれる１種以上の添加剤を含有する、［１］～［７］のいずれかに記載のエポキシ樹脂組成物。
［９］［１］～［８］のいずれかに記載のエポキシ樹脂組成物と（Ｄ）硬化剤とを含有する、硬化性樹脂組成物。
［１０］前記（Ｄ）硬化剤が、多官能フェノール類、ポリイソシアネート系化合物、アミン系化合物、酸無水物系化合物、イミダゾール系化合物、アミド系化合物、メルカプタン系化合物、カチオン重合開始剤、有機ホスフィン類、有機ホスホニウム塩、及びテトラフェニルボロン塩からなる群から選ばれる少なくとも１種以上である、［９］に記載の硬化性樹脂組成物。
［１１］前記（Ａ）エポキシ化合物１００質量部に対して、前記（Ｄ）硬化剤を０．１～１０００質量部含有する、［９］又は［１０］に記載の硬化性樹脂組成物。
［１２］更に、硬化促進剤（但し、硬化剤に該当するものは除く）を含有する、［９］～［１１］のいずれかに記載の硬化性樹脂組成物。
［１３］［９］～［１２］のいずれかに記載の硬化性組成物を硬化してなる、硬化物。
［１４］被接着体と、他の被接着体とが、［１３］に記載の硬化物を介して接着されてい
る、接着構造体。
［１５］Ｔ型剥離試験（－３０℃）において、前記被接着体と、他の被接着体との間の平均剥離強度が１７０Ｎ以上、最大剥離強度が４３０Ｎ以上である［１４］に記載の接着構造体。
［１６］式（１）で表されるエポキシ変性シリコーンからなる接着性付与剤。

（式（１）中、ｍは１以上の整数を表す。ｎはそれぞれ１以上の整数を表す。Ｒ^１及びＲ^２は、それぞれ独立して、アルキル基又は芳香族基を表す。Ｒ^３及びＲ^４は、それぞれ独立して、ヒドロキシフェニル基、カルビノール基、カルボキシ基、アミノ基及びメルカプト基からなる群から選ばれるエポキシ反応性官能基に由来する連結基を表す。） [1] Contains (A) an epoxy compound, (B) an adhesion aid, and (C) an epoxy-modified silicone in which an organic group containing an epoxy group is bonded to one of the ends of a chain silicone containing D units. Epoxy resin composition.
[2] The epoxy resin composition according to [1], wherein the organic group containing an epoxy group is an aromatic epoxy group and/or an aliphatic epoxy group.
[3] The epoxy resin composition according to [1] or [2], wherein the epoxy-modified silicone (C) is represented by formula (1).

(In formula (1), m represents an integer of 1 or more. n each represents an integer of 1 or more. R ¹ and R ² each independently represent an alkyl group or an aromatic group. ³ and ^R4 each independently represent a linking group derived from an epoxy-reactive functional group selected from the group consisting of a hydroxyphenyl group, a carbinol group, a carboxy group, an amino group, and a mercapto group.) [4 ] The epoxy resin composition according to [3], wherein R ¹ and R ² are methyl groups.
[5] Butadiene nitrile rubber and/or butadiene rubber in which the adhesion aid (B) has one or more terminal groups selected from the group consisting of a carboxy group, a hydroxyphenyl group, a carbinol group, an amino group, and a mercapto group. The epoxy resin composition according to any one of [1] to [4], comprising:
[6] The epoxy resin composition according to any one of [1] to [5], wherein the epoxy equivalent of the epoxy-modified silicone (C) is in the range of 1,500 to 5,000 g/equivalent.
[7] The epoxy resin composition according to any one of [1] to [6], which contains 2 to 20 parts by mass of the epoxy-modified silicone (C) based on 100 parts by mass of the epoxy compound (A).
[8] Furthermore, one or more additives selected from the group consisting of coupling agents, flame retardants, antioxidants, light stabilizers, plasticizers, reactive diluents, pigments, inorganic fillers, and organic fillers. The epoxy resin composition according to any one of [1] to [7], comprising:
[9] A curable resin composition containing the epoxy resin composition according to any one of [1] to [8] and (D) a curing agent.
[10] The curing agent (D) is a polyfunctional phenol, a polyisocyanate compound, an amine compound, an acid anhydride compound, an imidazole compound, an amide compound, a mercaptan compound, a cationic polymerization initiator, or an organic phosphine. The curable resin composition according to [9], wherein the curable resin composition is at least one selected from the group consisting of phosphonium salts, organic phosphonium salts, and tetraphenylboron salts.
[11] The curable resin composition according to [9] or [10], which contains 0.1 to 1000 parts by mass of the curing agent (D) based on 100 parts by mass of the epoxy compound (A).
[12] The curable resin composition according to any one of [9] to [11], further containing a curing accelerator (excluding those corresponding to curing agents).
[13] A cured product obtained by curing the curable composition according to any one of [9] to [12].
[14] An adhesive structure in which an object to be adhered and another object to be adhered are adhered via the cured product according to [13].
[15] In the T-peel test (-30°C), the average peel strength between the adherend and another adherend is 170N or more, and the maximum peel strength is 430N or more. Adhesive structure.
[16] An adhesion-imparting agent comprising an epoxy-modified silicone represented by formula (1).

(In formula (1), m represents an integer of 1 or more. n each represents an integer of 1 or more. R ¹ and R ² each independently represent an alkyl group or an aromatic group. ^{R 3} and ^R4 each independently represents a linking group derived from an epoxy-reactive functional group selected from the group consisting of a hydroxyphenyl group, a carbinol group, a carboxy group, an amino group, and a mercapto group.)

According to the present invention, it is possible to provide an epoxy resin composition with excellent low-temperature adhesive properties. Further, it is possible to provide a cured product containing the epoxy resin composition and an adhesive structure bonded by the cured product. Furthermore, epoxy-modified silicones with specific structures are expected to provide new uses as adhesion-imparting agents.

One form of the present invention is an epoxy-modified silicone (A) an epoxy compound, (B) an adhesion aid, and (C) an epoxy-modified silicone in which an organic group containing an epoxy group is bonded to one of the terminals of a chain-like silicone containing D units. Hereinafter, it is an epoxy resin composition containing (also simply referred to as (C) epoxy silicone). (C) Epoxy silicone has a chain-like silicone structure containing D units and exhibits adhesive strength even at low temperatures without freezing of molecular motion, giving it excellent adhesiveness to cured products. be able to.

[(A) Epoxy compound]
(A) The epoxy compound is a compound having two or more epoxy groups in the molecule. It may be a bifunctional epoxy compound having two epoxy groups in the molecule, or a trifunctional epoxy compound having three epoxy groups in the molecule. Preferably, it is a difunctional epoxy compound.

Examples of the bifunctional epoxy compound (A) include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol E diglycidyl ether, bisphenol Z diglycidyl ether, bisphenol S diglycidyl ether, bisphenol AD diglycidyl ether, and bisphenol acetophenone diglycidyl ether. Glycidyl ether, bisphenol trimethylcyclohexane diglycidyl ether, bisphenol fluorene diglycidyl ether, tetramethylbisphenol A diglycidyl ether, tetramethylbisphenol F diglycidyl ether, tetra-t-butylbisphenol A diglycidyl ether, tetramethylbisphenol S diglycidyl ether Biphenol diglycidyl ethers such as biphenol diglycidyl ether, tetramethylbiphenol diglycidyl ether, dimethylbiphenol diglycidyl ether, tetra-t-butylbiphenol diglycidyl ether; hydroquinone diglycidyl ether, Benzenediol diglycidyl ethers such as dihydroanthracene diglycidyl ether, methylhydroquinone diglycidyl ether, dibutylhydroquinone diglycidyl ether, resorcin diglycidyl ether, methylresorcin diglycidyl ether; dihydroanthrahydroquinone diglycidyl ether, dihydroxydiphenyl ether diglycidyl ether , thiodiphenol diglycidyl ether, dihydroxynaphthalene diglycidyl ether, and other aromatic diglycidyl ethers; Epoxy compounds with hydrogen added to the aromatic ring of diglycidyl ethers selected from glycidyl ethers; adipic acid, succinic acid, phthalic acid, tetrahydrophthalic acid, methylhexahydrophthalic acid, terephthalic acid, isophthalic acid, orthophthalic acid, biphenyl Epoxy resins produced from various carboxylic acids such as dicarboxylic acids and dimer acids, and epihalohydrin; ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,4- Butanediol diglycidyl ether, polytetramethylene glycol diglycidyl ether, 1,5-pentanediol diglycidyl ether, polypentamethylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, polyhexamethylene glycol diglycidyl ether, 1,7-heptanediol diglycidyl ether, polyheptamethylene glycol diglycidyl ether, 1,8-octanediol diglycidyl ether, 1,10-decanediol diglycidyl ether, 2,2-dimethyl-1,3-propanediol Examples include (poly)alkylene glycol diglycidyl ethers consisting only of a chain structure such as diglycidyl ether; alkylene glycol diglycidyl ethers having a cyclic structure such as 1,4-cyclohexanedimethanol diglycidyl ether;

Examples of trifunctional or more functional epoxy compounds include the following. In addition, in the following examples, "... type epoxy resin" refers to one in which the hydroxyl group is substituted with a glycidyl ether group. That is, for example, "4,4',4"-trihydroxytriphenylmethane type epoxy resin" is "4,4',4"-trihydroxytriphenylmethane whose hydroxyl group is substituted with glycidyl ether. As expected.

α,α-bis(4-hydroxyphenyl)-4-(4-hydroxy-α,α-dimethylbenzyl)-ethylbenzene type epoxy resin, 4,4',4''-trihydroxytriphenylmethane type epoxy resin, 4 , 4',4''-ethyridinetris(2-methylphenol) type epoxy resin, 4,4'-(2-hydroxybenzylidene)bis(2,3,6-trimethylphenol) type epoxy resin, 2,3, 4-trihydroxydiphenylmethane type epoxy resin, 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine type epoxy resin, 1,3,5-tris(4-hydroxyphenyl)benzene type epoxy Resin, 1,1,1-tris(4-hydroxyphenyl)ethane type epoxy resin, 4,4'-[1-[4-[1-(4-hydroxy-3,5-dimethylphenyl)-1-methyl Trifunctional epoxy resins such as ethyl]phenyl]ethylidene]bis(2-methylphenol) type epoxy resin, 2,6-bis(4-hydroxy-3,5-dimethylbenzyl)-4-methylphenol type epoxy resin; 2,2'-methylenebis[6-(2-hydroxy-5-methylbenzyl)-p-cresol type epoxy resin, 4-[bis(4-hydroxy-3-methylphenyl)methyl]benzene-1,2-diol type epoxy resin, 1,1,2,2-tetrakis(p-hydroxyphenyl)ethane type epoxy resin, α,α,α',α”-tetrakis(4-hydroxyphenyl)-p-xylene type epoxy resin, etc. Tetrafunctional epoxy resins; Pentafunctional epoxy resins such as 2,4,6-tris[(4-hydroxyphenyl)methyl]-1,3-benzenediol type epoxy resins; Diaminodiphenylmethane, aminophenol, xylene diamine, etc. Epoxy compounds manufactured from various amine compounds and epihalohydrin; Epoxy compounds manufactured from aliphatic polyols and epihalohydrin; phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, naphthol novolac type epoxy resin Epoxy resins, phenol aralkyl type epoxy resins, biphenylaralkyl type epoxy resins, phenol-modified xylene type epoxy resins, and these various phenols obtained through condensation reactions with various aldehydes such as hydroxybenzaldehyde, crotonaldehyde, and glyoxal. Examples include polyfunctional epoxy resins such as epoxy resins using various phenolic compounds such as polyhydric phenol resins, heavy oils or co-condensed resins of pitches, phenols, and formaldehydes.

Among these epoxy compounds, bisphenol diglycidyl ethers are preferred, and bisphenol A diglycidyl ether is more preferred.
Further, one kind or a combination of two or more kinds of bifunctional epoxy compounds and trifunctional or more functional epoxy compounds can also be used.

[(B) Adhesion aid]
(B) The adhesion aid is a compound added to improve the adhesiveness of the epoxy resin composition. One or more types of terminals selected from the group consisting of a carboxy group, a hydroxyphenyl group, a carbinol group, an amino group, and a mercapto group are not particularly limited as long as they can be blended into the epoxy resin composition to improve its adhesive properties. Butadiene nitrile rubber and/or butadiene rubber having groups are preferable from the viewpoint of low-temperature adhesion.
Among these, carboxyl-terminated butadiene nitrile rubber is more preferred. Carboxyl-terminated butadiene nitrile rubber, as represented by the following formula (2), is a copolymer of polybutadiene units and polyacrylonitrile units, and is an elastomer having carboxyl structures at both ends. As for the carboxyl terminal, a unit having a reactive group such as an epoxy group may be added thereto.

式（２）中、ｐは１以上の整数を表し、ｑは１以上の整数を表す。Ｒ^５およびＲ^６は独立してカルボキシル基、ヒドロキシフェニル基、カルビノール基などの水酸基含有基、アミノ基、及びメルカプト基からなる群より選ばれる１種または２種のエポキシ反応性官能基を有する１価の有機基を表す。

In formula (2), p represents an integer of 1 or more, and q represents an integer of 1 or more. R ⁵ and R ⁶ independently have one or two epoxy-reactive functional groups selected from the group consisting of a carboxyl group, a hydroxyl group-containing group such as a hydroxyphenyl group, a carbinol group, an amino group, and a mercapto group. Represents a monovalent organic group.

(B) The blending amount of the adhesion aid is not particularly limited, and is appropriately set depending on the adhesive application using the epoxy resin composition, but is usually 5 parts by mass per 100 parts by mass of the epoxy compound (A). The content is preferably 10 parts by mass or more, and usually 95 parts by mass or less, preferably 80 parts by mass or less.

[(C) Epoxy-modified silicone]
(C) Epoxy-modified silicone is a compound in which an organic group containing an epoxy group is bonded to either end of a chain silicone containing a D unit. By having a chain-like silicone unit containing a D unit, adhesive force is exhibited without freezing of molecular motion even at low temperatures, and therefore excellent adhesiveness can be imparted to the cured product.

(C) In the epoxy-modified silicone, the chain silicone unit may contain D unit silicone, but from the viewpoint of low-temperature adhesion, it is preferable that the D unit account for 50 mol% or more in all silicone units. , more preferably 80 mol% or more, and more preferably 100 mol%. Further, the chain silicone unit may be linear or branched, but is preferably a linear silicone.

(C) The organic group containing an epoxy group in the epoxy-modified silicone may be any organic group containing an epoxy group, but aromatic epoxy groups and/or aliphatic epoxy groups improve adhesive strength at low temperatures. preferred from the viewpoint of

(C) The epoxy-modified silicone is preferably represented by the following formula (1).

In formula (1), m represents an integer of 1 or more. Each n represents an integer of 1 or more, and multiple n's may be the same or different. R ¹ and R ² each independently represent an alkyl group or an aromatic group. Among these, at least one of R ¹ and R ² is preferably an alkyl group, and among the alkyl groups, an alkyl group having 1 to 4 carbon atoms is more preferable, and a methyl group is even more preferable. Moreover, it is more preferable that both R ¹ and R ² are alkyl groups.
Further, R ³ and R ⁴ independently represent a linking group derived from an epoxy-reactive functional group selected from the group consisting of a hydroxyphenyl group, a carbinol group, a carboxy group, an amino group, and a mercapto group.

In formula (1), m is usually 3 or more, preferably 10 or more on average, and usually 100 or less, preferably 50 or less. When m is within this range, compatibility with the epoxy resin composition is good, and sufficient low-temperature adhesiveness can be obtained.
In formula (1), each n represents an integer of 0 or more. On average, n is preferably 0 or more, and preferably 50 or less. When n is within this range, the epoxy-modified silicone itself has good fluidity, and the epoxy resin composition can be easily produced.

[Epoxy equivalent]
(C) The epoxy equivalent of the epoxy-modified silicone is a value measured according to JIS K7236, and is preferably 500 to 10,000 g/eq, more preferably 1500 to 5,000 g/eq, and 1500 to 4500 g /eq is particularly preferred. (C) When the epoxy equivalent of the epoxy-modified silicone is within the above range, the epoxy resin composition containing it is easy to prepare and the epoxy resin composition is excellent in handling, and the cured product after curing treatment is It can take on a morphology with excellent low-temperature adhesion.

(C) The amount of epoxy-modified silicone is not particularly limited, and is set appropriately depending on the adhesive application using the epoxy resin composition, but is usually 2 parts by mass per 100 parts by mass of (A) epoxy compound. The content is preferably 5 parts by mass or more, and usually 20 parts by mass or less, preferably 15 parts by mass or less.

[(C) Method for producing epoxy-modified silicone]
(C) The method for producing epoxy-modified silicone is not particularly limited, and it can be synthesized using a known method.

[Method for producing epoxy resin composition]
The method for producing an epoxy resin composition includes (A) an epoxy compound, (B) an adhesion aid, and (C) an epoxy resin composition in which an organic group containing an epoxy group is bonded to one of the terminals of a chain silicone containing D units. It can be obtained by kneading modified silicone.
Further, at this time, a curable resin composition can be obtained by usually adding a curing agent.

[Curing agent]
The curing agent (D) contained in the curable resin composition is a substance that contributes to the crosslinking reaction and/or chain extension reaction between the epoxy groups of the epoxy compound. In addition, in this specification, even if it is normally called a "curing accelerator", if it is a substance that contributes to the crosslinking reaction and/or chain lengthening reaction between the epoxy groups of the epoxy compound, it is considered to be a curing agent. shall be.

(D) Curing agents include polyfunctional phenols, polyisocyanate compounds, amine compounds, acid anhydride compounds, imidazole compounds, amide compounds, cationic polymerization initiators, organic phosphines, organic phosphonium salts, and Preferably, at least one of the group consisting of tetraphenylboron salts is used.

Examples of polyfunctional phenols include bisphenols such as bisphenol A, bisphenol F, bisphenol S, bisphenol B, bisphenol AD, bisphenol Z, and tetrabromobisphenol A, 4,4'-biphenol, 3,3',5, Biphenols such as 5'-tetramethyl-4,4'-biphenol; catechol, resorcinol, hydroquinone, dihydroxynaphthalenes; and hydrogen atoms bonded to the aromatic rings of these compounds are halogen groups, alkyl groups, aryl groups, and ethers. Examples include those substituted with non-interfering substituents such as groups, ester groups, and organic substituents containing hetero elements such as sulfur, phosphorus, and silicon.
Further examples include novolaks, resols, etc., which are polycondensates of these phenols, monofunctional phenols such as phenol, cresol, and alkylphenol, and aldehydes.

Examples of polyisocyanate compounds include tolylene diisocyanate, methylcyclohexane diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, dimer acid diisocyanate, trimethylhexamethylene diisocyanate, Examples include polyisocyanate compounds such as lysine triisocyanate. Furthermore, a polyisocyanate compound obtained by reacting these polyisocyanate compounds with a compound having at least two active hydrogen atoms such as an amino group, a hydroxyl group, a carboxyl group, or water, or 3 to 5 amounts of the above polyisocyanate compound. Examples include the body.

Examples of amine compounds include aliphatic primary, secondary, and tertiary amines, aromatic primary, secondary, and tertiary amines, cyclic amines, guanidines, and urea derivatives. Ethylene tetramine, diaminodiphenylmethane, diaminodiphenyl ether, metaxylene diamine, dicyandiamide, 1,8-diazabicyclo(5,4,0)-7-undecene, 1,5-diazabicyclo(4,3,0)-5-nonene, dimethyl Examples include urea and guanylurea.

Examples of acid anhydride compounds include phthalic anhydride, hexahydrophthalic anhydride, trimellitic anhydride, and condensates of maleic anhydride and unsaturated compounds.

Examples of imidazole compounds include 1-isobutyl-2-methylimidazole, 2-methylimidazole, 1-benzyl-2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, benzimidazole, etc. It will be done. Although the imidazole compound also functions as a curing accelerator, which will be described later, it is classified as a curing agent in this specification.

Examples of amide compounds include dicyandiamide and derivatives thereof, polyamide resins, and the like.

The cationic polymerization initiator is one that generates cations by heat or active energy ray irradiation, and includes aromatic onium salts and the like. Specifically, anion components such as SbF ₆ ^- , BF ₄ ^- , AsF ₆ ^- , PF ₆ ^- , CF ₃ SO ₃ ^2- , B(C ₆ F ₅ ) ₄ ^- and iodine, sulfur, nitrogen, phosphorus, etc. Examples include compounds consisting of an aromatic cation component containing an atom of

Examples of organic phosphine include tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, phenylphosphine, and the like.
Examples of organic phosphonium salts include tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium ethyltriphenylborate, and tetrabutylphosphonium tetrabutylborate.
Examples of tetraphenylboron salts include 2-ethyl-4-methylimidazole tetraphenylborate, N-methylmorpholine tetraphenylborate, and the like.

In addition to the curing agents listed above, organic acid dihydrazides, halogenated boron amine complexes, and the like can also be used as curing agents.
Among the above curing agents, latent dicyandiamide is preferably used, but each may be used alone, or two or more of the same or different types may be used in combination.
The amount of the curing agent (D) is not particularly limited, and is usually at least 0.1 part by mass, preferably at least 0.5 part by mass, based on 100 parts by mass of the epoxy compound (A). , and usually 1000 parts by mass or less, preferably 500 parts by mass or less.

When using polyfunctional phenols, amine compounds, or acid anhydride compounds as a curing agent, the functional groups in the curing agent (hydroxyl groups of polyfunctional phenols, hydroxyl groups of amine compounds, It is preferable that the equivalent ratio of the amino group or the acid anhydride group of the acid anhydride compound is in the range of 0.8 to 1.5. When using a polyisocyanate compound, it is preferable to use it in an equivalent ratio of the number of isocyanate groups in the polyisocyanate compound to the number of hydroxyl groups in the epoxy resin composition in the range of 1:0.01 to 1:1.5. . When an imidazole compound is used, it is preferably used in an amount of 0.5 to 10 parts by weight based on 100 parts by weight of the total epoxy resin component as solid content in the epoxy resin composition. When an amide compound is used, it is preferably used in an amount of 0.1 to 20% by mass based on the total amount of all epoxy resin components and the amide compound as solid content in the epoxy resin composition. When using a cationic polymerization initiator, it is preferably used in an amount of 0.01 to 15 parts by mass based on 100 parts by mass of all epoxy resin components as solid content in the epoxy resin composition. When organic phosphines are used, they are preferably used in an amount of 0.1 to 20% by mass based on the total amount of all epoxy resin components and organic phosphines as solids in the epoxy resin composition.

[Other ingredients]
The curable resin composition can contain other components in addition to the components listed above. Other components include, for example, curing accelerators (excluding those that fall under the above-mentioned curing agents), coupling agents, flame retardants, antioxidants, light stabilizers, plasticizers, reactive diluents, pigments, Examples include inorganic fillers and organic fillers. The other components listed above can be used in appropriate combinations depending on the desired physical properties of the curable resin composition.
Other components can be contained within a range that does not inhibit the curing of the present invention, but the content is usually 10 parts by mass or less, and 5 parts by mass or less, based on 100 parts by mass of (A) epoxy compound. It is preferable that

[Cured product]
A cured product can be obtained by curing the curable resin composition. "Curing" here means intentionally curing the epoxy compound by heat and/or light, and the degree of curing may be controlled depending on the desired physical properties and use.
The method for curing the curable resin composition to form a cured product varies depending on the components and amounts contained in the curable resin composition, and the shape of the compound, but is usually at 50 to 200°C for 5 seconds to 180 minutes. The heating conditions include:

[Application]
Curable resin compositions containing epoxy resin compositions have excellent adhesion, especially at low temperatures, and are therefore used in a wide range of fields such as automobiles, ships, aviation, space, civil engineering, and architecture, for various metal parts, carbon fibers, etc. Alternatively, it can be suitably used as a structural adhesive used to join the same or different types of glass fiber reinforced resins, thermoplastic resins, and curable resins, and is especially suitable as an automotive structural adhesive. can. Furthermore, the curable resin composition can be used for various paints, various adhesives, various molded products, and the like.

[Adhesive structure]
By using the above-mentioned curable resin composition as an adhesive, an adhesive structure is obtained in which an object to be adhered and another object to be adhered are adhered via a cured product of the above-mentioned curable resin composition. Can be done.
The bonded structure bonded with the above-mentioned curable resin composition preferably has an average peel strength of 170N or more between an object to be adhered and another object to be adhered, and a maximum peel strength of 430N or more. is preferred.
The average peel strength and the maximum peel strength are peel strengths measured by a T-peel test using a tensile tester, and the method is performed according to JIS K 6854.

式（１）中、ｍは１以上の整数を表す。ｎはそれぞれ１以上の整数を表す。Ｒ^１及びＲ^２は、それぞれ独立して、アルキル基又は芳香族基を表す。Ｒ^３及びＲ^４は、それぞれ独立して、ヒドロキシフェニル基、カルビノール基、カルボキシ基、アミノ基及びメルカプ
ト基からなる群から選ばれるエポキシ反応性官能基に由来する連結基を表す。 [Adhesive agent]
Another embodiment of the present invention is an adhesion-imparting agent made of an epoxy-modified silicone represented by formula (1).

In formula (1), m represents an integer of 1 or more. Each n represents an integer of 1 or more. R ¹ and R ² each independently represent an alkyl group or an aromatic group. R ³ and R ⁴ each independently represent a linking group derived from an epoxy-reactive functional group selected from the group consisting of a hydroxyphenyl group, a carbinol group, a carboxy group, an amino group, and a mercapto group.

The epoxy-modified silicone represented by formula (1) can impart low-temperature adhesive properties to adhesives containing epoxy compounds. Usually, the effect can be exhibited by adding 2 to 20 parts by weight per 100 parts by weight of the epoxy compound.

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.
[(C) Production of epoxy-modified silicone compound]
(Manufacturing example 1)
In a separable flask reactor equipped with a thermometer, dropping funnel, stirrer, nitrogen inlet tube, and cooling tube, 40.0 g of phenol-terminated polydimethylsiloxane KF2201 (hydroxyl group equivalent) manufactured by Shin-Etsu Chemical Co., Ltd. and Mitsubishi Chemical Corporation were placed. After 9.6 g of bisphenol A type epoxy resin jER828US manufactured by J.D. Co., Ltd. was charged and stirred and heated to 120° C., 0.60 g of trimethylammonium chloride was added and the mixture was heated and stirred for 1.5 hours. The obtained epoxy modified silicone resin (C-1) had an epoxy equivalent weight of 1979 g/eq.

(Manufacturing example 2)
After reacting the epoxy-modified silicone resin in the same manner as in Production Example 1, 11.9 g of bisphenol A and 19.2 g of bisphenol A type epoxy resin jER828US were added at 120° C. The mixture was heated and stirred for hours. This additional addition of bisphenol A and bisphenol A type epoxy resin and heating and stirring were repeated once more. The obtained epoxy modified silicone resin (C-2) had an epoxy equivalent of 4307 g/eq. Met.

(Manufacturing example 3)
After reacting the epoxy-modified silicone resin in the same manner as in Production Example 1, 17.8 g of bisphenol A and 28.8 g of bisphenol A type epoxy resin jER828US were further added at 120°C to give an additional 1.5 g of epoxy resin. The mixture was heated and stirred for hours. This additional addition of bisphenol A and bisphenol A type epoxy resin and heating and stirring were repeated two more times. The obtained epoxy modified silicone resin (C-3) had an epoxy equivalent of 5503 g/eq. Met.

[Preparation and evaluation of adhesive composition composed of epoxy group-containing silicone compound]
(Example, comparative example)
(A) Bisphenol A epoxy resin (JER828 manufactured by Mitsubishi Chemical Corporation) as the epoxy compound, (D) Dicyandiamide (DICY15 manufactured by Mitsubishi Chemical Corporation) as the curing agent, and 3-(3,4-dichlorophenyl) as the curing accelerator. )-1,1-dimethylurea (manufactured by Tokyo Kasei Kogyo Co., Ltd.), (B) carboxyl group-terminated butadiene nitrile rubber (HyproCTBN, manufactured by Huntsman) as an adhesion aid, 100 μm silica beads as a gap material, and the above Production Example 1 Using the epoxy-modified silicone resin (C-1) produced in Table 1, a curable resin composition was prepared by mixing the composition shown in Table 1 in a water bath at 70°C. Note that dicyandiamide and 3-(3,4-dichlorophenyl)-1,1-dimethylurea were each pre-kneaded with bisphenol A epoxy resin in a three-roll mill (BR-100V manufactured by Imex Corporation). used.

The obtained curable resin composition was prepared in accordance with JIS K 6854 by applying the curable resin composition to one side of each 25 mm wide stainless steel plate as an adherend, and then bonding the coated surfaces together. After that, heat curing at 180℃ x 20 minutes, and then heat curing at 23℃ x 50% RH.
Conditions were adjusted for 2 hours or more to prepare a T-shaped peel test piece.
Using the above T-peel test piece, a T-peel test was conducted using a tensile tester at 23°C and -30°C, n=3. The peeling speed was set at 200 mm per minute, and the average peeling force required to peel off the adherend was measured. The results are shown in Table 1.

The epoxy resin of the present invention and the epoxy resin composition of the present invention blended with the same have excellent adhesive properties, especially at low temperatures, and are therefore used in a wide range of fields such as automobiles, ships, aviation, space, civil engineering, and architecture. It can be suitably used as a structural adhesive used to join various metal parts, carbon fiber or glass fiber reinforced resins, thermoplastic resins, and hardening resins of the same type or different types.In particular, it can be used as a structural adhesive for automobiles. It can be suitably used. Furthermore, the curable resin composition of the present invention can be used for various paints, various adhesives, various molded products, and the like.

Claims (16)

An epoxy resin composition containing (A) an epoxy compound, (B) an adhesion aid, and (C) an epoxy-modified silicone in which an organic group containing an epoxy group is bonded to one of the ends of a chain silicone containing D units. thing. The epoxy resin composition according to claim 1, wherein the organic group containing an epoxy group is an aromatic epoxy group and/or an aliphatic epoxy group. The epoxy resin composition according to claim 1, wherein the epoxy-modified silicone (C) is represented by formula (1).

(In formula (1), m represents an integer of 1 or more. n each represents an integer of 1 or more. R ¹ and R ² each independently represent an alkyl group or an aromatic group. ³ and ^R4 each independently represent a linking group derived from an epoxy-reactive functional group selected from the group consisting of a hydroxyphenyl group, a carbinol group, a carboxy group, an amino group, and a mercapto group.) The epoxy resin composition according to claim 3, wherein R ¹ and R ² are methyl groups. The adhesion aid (B) contains butadiene nitrile rubber and/or butadiene rubber having one or more terminal groups selected from the group consisting of a carboxy group, a hydroxyphenyl group, a carbinol group, an amino group, and a mercapto group. The epoxy resin composition according to claim 1. The epoxy resin composition according to claim 1, wherein the epoxy equivalent of the epoxy-modified silicone (C) is in the range of 1500 to 5000 g/equivalent. The epoxy resin composition according to claim 1, containing 2 to 20 parts by mass of the epoxy-modified silicone (C) based on 100 parts by mass of the epoxy compound (A). Furthermore, it contains one or more additives selected from the group consisting of coupling agents, flame retardants, antioxidants, light stabilizers, plasticizers, reactive diluents, pigments, inorganic fillers, and organic fillers. , the epoxy resin composition according to claim 1. A curable resin composition comprising the epoxy resin composition according to claim 1 and (D) a curing agent. The curing agent (D) is a polyfunctional phenol, a polyisocyanate compound, an amine compound, an acid anhydride compound, an imidazole compound, an amide compound, a mercaptan compound, a cationic polymerization initiator, an organic phosphine, or an organic compound. The curable resin composition according to claim 9, which is at least one selected from the group consisting of phosphonium salts and tetraphenylboron salts. 0.1 to 100 parts of the curing agent (D) to 100 parts by mass of the epoxy compound (A)
The curable resin composition according to claim 9, containing 0 parts by mass. The curable resin composition according to claim 9, further comprising a curing accelerator (excluding those corresponding to curing agents). A cured product obtained by curing the curable composition according to claim 9. An adhesive structure in which an object to be adhered and another object to be adhered are adhered via the cured product according to claim 13. The bonded structure according to claim 14, wherein the average peel strength between the adherend and another adherend is 170N or more and the maximum peel strength is 430N or more in a T-peel test (-30°C). . An adhesive agent consisting of an epoxy-modified silicone represented by formula (1).

(In formula (1), m represents an integer of 1 or more. n each represents an integer of 1 or more. R ¹ and R ² each independently represent an alkyl group or an aromatic group. ^{R 3} and ^R4 each independently represents a linking group derived from an epoxy-reactive functional group selected from the group consisting of a hydroxyphenyl group, a carbinol group, a carboxy group, an amino group, and a mercapto group.)