Epoxy resin composition, epoxy resin cured product, and epoxy adhesive

Abstract

To provide an epoxy resin composition which expresses such characteristics as to increase both elongation characteristics and tensile shear strength even when a curing temperature is lowered, while controlling a domain size, a cured product of the same, and an epoxy adhesive.SOLUTION: An epoxy resin composition contains (A) an epoxy resin containing two or more epoxy groups in one molecule, and (B) a prepolymer that is a reactant of (B-1) and (C-1), urethane bond-containing polyorganosiloxane represented by the following general formula (1) and (C-1) is an aromatic amine curing agent, in which the number of N-H bonds in (C-1) is twice or more of the number of epoxy groups in (B-1), and (C-2) a non-aromatic amine curing agent.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an epoxy resin composition, a cured product thereof, and an epoxy adhesive. [Background technology]

[0002] In recent years, the transition from conventional engine vehicles to electric vehicles has progressed, and the way automotive structures are manufactured has also undergone major changes. Furthermore, in terms of bonding components, in addition to joining homogeneous materials, there is a growing need to join dissimilar materials, such as aluminum and steel, aluminum and steel plate, and aluminum and carbon fiber composites (CFRP), in order to reduce the weight of the vehicle body. Epoxy adhesives are primarily used as body shell adhesives to join such dissimilar materials and increase the rigidity of automobiles. Epoxy adhesives play a vital role as adhesives for joining automobiles due to their excellent mechanical strength, electrical insulation, heat resistance, chemical resistance, water resistance, low shrinkage, and adhesion.

[0003] However, even epoxy adhesives capable of achieving high-strength adhesion have the problem of low toughness, i.e., low impact peel strength. To solve this problem, development is underway on epoxy adhesives containing polyurethane polymers terminated with epoxy groups as an impact modifier, as described in Patent Document 1.

[0004] However, with epoxy adhesives of the above structure, it is extremely difficult to increase both the elongation and tensile shear strength by mixing urethane polymers.Furthermore, in recent years, attention has been focused on technologies for joining dissimilar materials with resins such as CFRP, but while improving both the elongation and tensile shear strength, there is also a need to reduce the curing temperature conditions, taking into account the heat resistance of the resin and its environmental impact. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 2010-521570 Summary of the Invention [Problem to be solved by the invention]

[0006] In view of the above problems, an object of the present invention is to provide an epoxy resin composition having a composition that exhibits the properties of increasing both elongation and tensile shear strength even when the curing temperature is lowered while controlling the domain size, a cured product thereof, and an epoxy adhesive. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides an epoxy resin composition, comprising: (A) an epoxy resin containing two or more epoxy groups in one molecule; (B) a prepolymer which is a reaction product of the following (B-1) and (C-1): (B-1) a urethane bond-containing polyorganosiloxane represented by the following general formula (1): [ka] (In the formula, R 1 are each independently a group selected from an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, or a hydroxyl group; X are each independently an alkylene group having 1 to 10 carbon atoms; Y are each independently a group selected from an alkylene group having 5 to 30 carbon atoms, an arylene group having 6 to 30 carbon atoms, and an aralkylene group having 7 to 30 carbon atoms; Z are each independently an alkylene group having 1 to 20 carbon atoms, and the alkylene group in Y and Z may have one or more ether bonds in the molecular chain; n is an integer of 0 to 100; and m is 1 or 2. (C-1) aromatic amine curing agent: an amount such that the number of NH bonds in (C-1) is at least twice the number of epoxy groups in (B-1), and (C-2) Non-aromatic amine curing agent The epoxy resin composition includes:

[0008] In this epoxy resin composition, the polyorganosiloxane moiety in the prepolymer (B) is poorly compatible with the epoxy resin (A), resulting in a sea-island structure in which the (B) component forms islands and the (A) component forms a sea. The presence of urethane groups in the (B-1) component in the (B) component results in partial crystallization within the island components, resulting in the formation of a high-strength siloxane urethane polymer that cannot be achieved with siloxane alone. Furthermore, the urethane bonds in the (B) component and the residues resulting from the reaction of the epoxy groups in the (B-1) component with some of the NH bonds in the (C-1) component have good affinity with the epoxy resin (A), resulting in adequate compatibility at the interface between the island and sea regions. Furthermore, the prepolymer (B), a component of the epoxy resin composition of the present invention, is formed by the reaction of the epoxy groups in the (B-1) component with some of the NH groups in the (C-1) component. The amino groups derived from the (C-1) component also bond with the epoxy resin (A), resulting in adequate compatibility at the interface between the island and sea regions. As a result, when the sea-island structure is formed, the island structures centered on component (B) are connected to component (A) of the sea structure to form an epoxy resin structure, which results in an epoxy resin composition that can increase both elongation properties and tensile shear strength compared to when component (B) is not present.

[0009] Furthermore, by shortening the molecular chain length of the general formula (1) by setting m to 1 or 2, the island structures formed are well dispersed, and an epoxy resin can be obtained without the island components coalescing and separating. At the same time, the strength of the siloxane urethane polymer can be further increased. Furthermore, by shortening the molecular chain length of the general formula (1) by setting m to 1 or 2, the distance between the epoxy groups at both ends of component (B) is shortened, which strengthens the epoxy resin structure itself.

[0010] The present invention is characterized in that the component (C) contains (C-1) an aromatic amine curing agent and (C-2) a non-aromatic amine curing agent.

[0011] The use of the aromatic amine curing agent (C-1) provides good curing properties, and by forming a prepolymer with the component (B-1), compatibility with the component (A) is partially improved, allowing control of the island structure. Furthermore, the inclusion of the non-aromatic amine curing agent (C-2) allows for a reduction in the curing temperature. Furthermore, the size of the island structures of the component (B) can be controlled, resulting in good curing properties.

[0012] In the present invention, the component (A) is preferably a bisphenol-type epoxy resin.

[0013] Such an epoxy resin composition can enhance the properties of various selected and used bisphenol-type epoxy resins, and can provide an epoxy resin composition that can increase both elongation properties and tensile shear strength compared to when the bisphenol-type epoxy resin is used alone.

[0014] In the present invention, the polyorganosiloxane represented by the general formula (1) preferably has a number average molecular weight of 500 to 100,000 in terms of polystyrene standard substance.

[0015] With such an epoxy resin composition, the size of the structures that make up the island structures of the sea-island structure does not become too large, and microphase separation can be formed. Furthermore, by selecting the number average molecular weight within this range, the size of the island structures can be controlled.

[0016] In the present invention, the polyorganosiloxane represented by the general formula (1) preferably has an epoxy equivalent of 300 to 5,000 g / mol.

[0017] With such an epoxy resin composition, the size of the structures that make up the island structures of the sea-island structure does not become too large, and microphase separation can be formed. Furthermore, by selecting the epoxy equivalent within this range, the size of the island structures can be controlled.

[0018] In the present invention, the component (B-1) preferably contains hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in a total amount of 3,000 ppm or less.

[0019] By reducing these cyclic low-molecular-weight siloxanes, it is possible to avoid problems such as a decrease in adhesion due to the low-molecular-weight components bleeding out onto the surface of the cured product, and contamination of the surrounding environment due to the volatilization of the low-molecular-weight components.

[0020] In the present invention, it is preferable that the amount of NH bonds in the component (C-1) is 30 to 70 mol % of the total amount of NH bonds in the components (C-1) and (C-2).

[0021] Such an epoxy resin composition is easy to handle because it does not undergo a crosslinking reaction or become a gel due to high molecular weight when preparing the prepolymer that is the component (B).

[0022] In the present invention, the component (C-1) is preferably a compound represented by the following general formula (I) or general formula (II), or an aromatic polyamine. [ka] (In the formula, R's are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R's are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and n represents the number of substituents and is an integer of 0 to 4.)

[0023] Such an epoxy resin composition has good dispersibility of the prepolymerized component (B) in the component (A), and when cured, can provide sufficient strength and elongation.

[0024] In this case, the component (C-1) is preferably 4,4'-diaminodiphenylmethane.

[0025] Such an epoxy resin composition has better dispersibility of the prepolymerized (B) component in the (A) component, and when cured, can provide more sufficient strength and elongation.

[0026] In the present invention, the component (C-2) is preferably represented by the following general formula (III) or (IV). [ka] (In the formula, R's are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R's are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and n represents the number of substituents and is an integer of 0 to 4.)

[0027] Such an epoxy resin composition can be sufficiently cured at a low temperature without impairing the dispersibility of component (B).

[0028] In this case, the component (C-2) is preferably selected from m-xylylenediamine and its derivatives.

[0029] Such an epoxy resin composition can be sufficiently cured at a lower temperature without impairing the dispersibility of component (B).

[0030] In the present invention, the epoxy resin composition preferably further contains a filler (D).

[0031] Such an epoxy resin composition can enhance the mechanical strength.

[0032] The present invention also provides a cured epoxy resin product obtained by curing the above-described epoxy resin composition.

[0033] Such an epoxy resin cured product can have improved elongation and tensile strength compared to conventional epoxy resin cured products, making the cured product tougher.

[0034] The present invention also provides an epoxy adhesive comprising the epoxy resin composition described above.

[0035] Such an epoxy adhesive can stably provide the desired properties. [Effects of the Invention]

[0036] As described above, when using the epoxy resin composition of the present invention, the organosiloxane moieties in the prepolymer (component (B)) are incompatible with the epoxy resin (component (A)), resulting in the formation of a sea-island structure in which component (B) constitutes islands and component (A) constitutes the sea. The presence of urethane groups in component (B-1) in component (B) causes partial crystallization within the island components, resulting in the formation of a high-strength siloxane urethane polymer that cannot be achieved with siloxane alone. Furthermore, the urethane bonds in component (B) and the residues resulting from the reaction of epoxy groups in component (B-1) with some of the NH bonds in component (C-1) have good affinity with the epoxy resin (component (A)), resulting in adequate compatibility at the interface between the island and sea regions. Furthermore, component (B), a constituent element of the epoxy resin composition of the present invention, is formed by reaction of epoxy groups in component (B-1) with some of the NH groups in component (C-1). Because of the amino groups derived from component (C-1), it also bonds with the epoxy resin (component (A)). As a result, when the sea-island structure is formed, the island structures centered on component (B) are connected to component (A) of the sea structure to form an epoxy resin structure, which results in an epoxy resin composition that can increase both elongation properties and tensile shear strength compared to when component (B) is not present.

[0037] It is generally known that the curing temperature can be lowered by using an aromatic amine curing agent and an aliphatic amine curing agent in combination with an amine curing agent. However, it has been surprisingly found that the domain size of the island component can be controlled by the epoxy resin composition of the present invention, and both the elongation property and the tensile shear strength can be increased.

[0038] In this way, when the epoxy resin composition of the present invention is used, it is possible to increase both the elongation properties and the tensile shear strength of the cured product compared to a composition that does not contain the prepolymer, which is component (B).

[0039] The cured epoxy resin product of the present invention is obtained by curing the above-mentioned epoxy resin composition, and as described above, it is possible to obtain a cured product having both improved elongation properties and tensile shear strength compared to conventional cured epoxy resin products.

[0040] The epoxy resin composition of the present invention can also be used as an epoxy adhesive, which can provide a cured product having both improved elongation and tensile shear strength compared to conventional cured epoxy resin products. DETAILED DESCRIPTION OF THE INVENTION

[0041] As described above, there has been a need for the development of an epoxy resin composition having a composition that exhibits the properties of increasing both elongation properties and tensile shear strength, a cured product thereof, and an epoxy adhesive.

[0042] As a result of extensive research into the above-mentioned problems, the present inventors have found that an epoxy resin composition containing (A) an epoxy resin containing two or more epoxy groups in one molecule, (B) a prepolymer (B-1) a reaction product of a urethane bond-containing polyorganosiloxane and (C-1) a specific amount of an aromatic amine curing agent, and (C-2) a non-aromatic amine curing agent can increase both the elongation properties and the tensile shear strength, and have completed the present invention.

[0043] That is, the present invention provides an epoxy resin composition, (A) an epoxy resin containing two or more epoxy groups in one molecule; (B) a prepolymer which is a reaction product of the following (B-1) and (C-1): (B-1) a urethane bond-containing polyorganosiloxane represented by the following general formula (1): [ka] (In the formula, R 1 are each independently a group selected from an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, or a hydroxyl group; X are each independently an alkylene group having 1 to 10 carbon atoms; Y are each independently a group selected from an alkylene group having 5 to 30 carbon atoms, an arylene group having 6 to 30 carbon atoms, and an aralkylene group having 7 to 30 carbon atoms; Z are each independently an alkylene group having 1 to 20 carbon atoms, and the alkylene group in Y and Z may have one or more ether bonds in the molecular chain; n is an integer of 0 to 100; and m is 1 or 2. (C-1) aromatic amine curing agent: an amount such that the number of NH bonds in (C-1) is at least twice the number of epoxy groups in (B-1), and (C-2) Non-aromatic amine curing agent The epoxy resin composition is characterized by comprising:

[0044] The present invention will be described in detail below, but the present invention is not limited thereto.

[0045] [Epoxy resin composition] The epoxy resin composition according to the first embodiment of the present invention comprises: (A) an epoxy resin containing two or more epoxy groups in one molecule; (B) a prepolymer which is a reaction product of the following (B-1) and (C-1): (B-1) a polyorganosiloxane having a specific structure and containing a urethane bond; (C-1) a specific amount of an aromatic amine curing agent, and (C-2) Non-aromatic amine curing agent Each component will be described in detail below.

[0046] [(A) Epoxy resin] The epoxy resin (A) containing two or more epoxy groups per molecule in the epoxy resin composition of the present invention can be any known epoxy resin, and is not particularly limited as long as it is not the component (B-1) described below. Examples include bisphenol-type epoxy resins such as bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, and bisphenol S-type epoxy resins; alicyclic epoxy resins such as dicyclopentadiene-type epoxy resins and 3,4-epoxycyclohexenylmethyl-3',4'-epoxycyclohexenecarboxylate; polyfunctional phenol-type epoxy resins such as resorcinol-type epoxy resins; stilbene-type epoxy resins, triazine-skeleton-containing epoxy resins, fluorene-skeleton-containing epoxy resins, triphenolalkane-type epoxy resins, biphenyl-type epoxy resins, xylylene-type epoxy resins, biphenylaralkyl-type epoxy resins, naphthalene-type epoxy resins, and diglycidyl ether compounds of polycyclic aromatics such as anthracene. These can be used alone or in combination of two or more. Bisphenol-type epoxy resins are preferred.

[0047] The epoxy equivalent of the epoxy resin of component (A) is not particularly limited, but from the viewpoint of the usable time after mixing and the strength of the cured product, it is preferably 50 to 5,000 g / eq, and more preferably 75 to 2,500 g / eq, calculated per solid content.

[0048] The properties of the epoxy resin of component (A) are not particularly limited, but it is preferably liquid at 25°C, with a viscosity of more preferably 10 to 100,000 mPa·s, and even more preferably 20 to 50,000 mPa·s. The viscosity is measured using a Brookfield rotational viscometer (B-type viscometer) as described in JIS K 7117-1:1999.

[0049] [(B) Prepolymer] The (B) component contained in the epoxy resin composition of the present invention takes the form of a prepolymer, which is a reaction product of a urethane bond-containing polyorganosiloxane of general formula (1) (component (B-1)) described below and an aromatic amine curing agent (C-1) described below. The amount is such that the ratio of the number of NH bonds (moles) in the aromatic amine curing agent (C-1) to the number of epoxy groups (moles) in the urethane bond-containing polyorganosiloxane of general formula (1) (component (B-1)) is at least two times, preferably at least four times. If the amount is less than two times, the aromatic amine curing agent (C-1) will have too few NH bonds in its molecule, resulting in an ultrahigh molecular weight product or crosslinking reaction, resulting in a component that is difficult to handle and insoluble.

[0050] In the method for producing the prepolymer, for example, the prepolymer is obtained by reacting at 40 to 150° C. for 0.1 to 3 hours.

[0051] [(B-1) Urethane bond-containing polyorganosiloxane] The urethane bond-containing polyorganosiloxane, which is the component (B-1) in the prepolymer (B) contained in the epoxy resin composition of the present invention, is a urethane bond-containing polyorganosiloxane represented by the following general formula (1). [ka] (In the formula, R 1 are each independently a group selected from an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, or a hydroxyl group; X are each independently an alkylene group having 1 to 10 carbon atoms; Y are each independently a group selected from an alkylene group having 5 to 30 carbon atoms, an arylene group having 6 to 30 carbon atoms, and an aralkylene group having 7 to 30 carbon atoms; Z are each independently an alkylene group having 1 to 20 carbon atoms, and the alkylene group in Y and Z may have one or more ether bonds in the molecular chain; n is an integer of 0 to 100; and m is 1 or 2.

[0052] In the above general formula (1), R 1are each independently selected from an alkyl group having 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms, an aryl group having 6 to 12 carbon atoms, preferably 6 to 9 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, preferably 7 to 10 carbon atoms, or a hydroxyl group. Specific examples thereof include straight-chain or branched-chain alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cycloalkyl groups such as cyclohexyl; aryl groups such as phenyl and naphthyl; and aralkyl groups such as benzyl. Of these, a methyl group or a phenyl group is preferred.

[0053] In the above general formula (1), X's are each independently an alkylene group having 1 to 10 carbon atoms, preferably 1 to 8 carbon atoms.

[0054] Specific examples of the alkylene group having 1 to 10 carbon atoms include a methylene group, an ethylene group, a propylene group, an n-hexylene group, an n-octylene group, etc. A methylene group is preferred.

[0055] In the above general formula (1), Y's are each independently a group selected from an alkylene group having 5 to 30 carbon atoms, an arylene group having 6 to 30 carbon atoms, and an aralkylene group having 7 to 30 carbon atoms.

[0056] The alkylene group having 5 to 30 carbon atoms may be linear, branched, or cyclic, and specific examples thereof include linear or branched alkylene groups such as an n-pentylene group, an n-hexylene group, an n-heptylene group, an n-octylene group, a 2-ethylhexylene group, an n-decylene group, an n-undecylene group, an n-dodecylene group, an n-tridecylene group, an n-tetradecylene group, an n-pentadecylene group, an n-hexadecylene group, an n-heptadecylene group, an n-octadecylene group, an n-nonadecylene group, and an n-eicosanylene group.

[0057] The alkylene group may have one or more ether bonds in the middle of the molecular chain, specifically, a group containing an ether bond such as a pentyleneoxy group, a hexyleneoxy group, or a heptyleneoxy group, and may have multiple ether bonds.

[0058] Examples of the arylene group having 6 to 30 carbon atoms include an o-phenylene group, an m-phenylene group, a p-phenylene group, a 3,5-tolylene group, a 2,4-tolylene group, a 2,6-tolylene group, a 1,2-naphthylene group, a 1,8-naphthylene group, a 2,3-naphthylene group, a 4,4'-biphenylene group, and a 4,4'-methylenebisphenyl group.

[0059] Examples of the aralkylene group having 7 to 30 carbon atoms include an o-xylylene group, an m-xylylene group, a p-xylylene group, and a 1,3-phenylenebis(2-propyl) group.

[0060] The above Y is preferably exemplified by the following groups: The dotted line indicates the bonding site with the nitrogen atom of the urethane bond in the above general formula (1), and hydrogen atoms are conventionally omitted. [ka]

[0061] In the general formula (1), Z's are each independently an alkylene group having 1 to 20 carbon atoms, preferably 3 to 10 carbon atoms. The alkylene group having 1 to 20 carbon atoms may have one or more ether bonds interposed therein. Preferred are a propylene group (-CH2CH2CH2-) and an ethyleneoxypropylene group (-CH2CH2OCH2CH2CH2-), where * represents a bond with the oxygen atom of the urethane bond in the general formula (1).

[0062] In the above general formula (1), n ​​represents an integer of 0 to 100. Preferably, n is an integer of 0 to 60.

[0063] In the above general formula (1), m represents the average degree of polymerization, and is 1 or 2, preferably 1. If m is 3 or more, it is not preferable because a uniform cured product cannot be obtained.

[0064] The urethane bond-containing polyorganosiloxane of the present invention represented by the general formula (1) preferably has a number average molecular weight of 500 to 100,000, more preferably 500 to 50,000, and even more preferably 500 to 20,000, calculated relative to a polystyrene standard. Within this range, the epoxy groups at both ends react with the curing agent, resulting in a molecular weight sufficient to obtain a cured product. Furthermore, the size of the structures constituting the island structures of the sea-island structure does not become too large, allowing for microphase separation to be formed. Furthermore, by selecting a number average molecular weight within this range, the size of the island structures can be controlled. The number average molecular weight refers to the number average molecular weight calculated relative to a polystyrene standard, as determined by gel permeation chromatography (GPC) measurement under the following measurement conditions:

[0065] [Measurement conditions] Developing solvent: tetrahydrofuran (THF) Flow rate: 0.6mL / min Detector: Refractive index detector (RI) Column: TSK Guardcolumn SuperH-H TSKgel SuperHM-N(6.0mmI.D.×15cm×1) TSKgel SuperH2500(6.0mmI.D.×15cm×1) (All manufactured by Tosoh Corporation) Column temperature: 40℃ Sample injection volume: 50 μL (0.3% by mass THF solution)

[0066] In the urethane bond-containing polyorganosiloxane of the present invention represented by the general formula (1), the epoxy equivalent (g / mol) is preferably 300 to 5,000 g / mol, more preferably 500 to 2,500 g / mol. This range ensures that the epoxy groups at both ends react with the curing agent, providing a sufficient amount to obtain a cured product with good physical properties. Furthermore, the size of the structures constituting the island structures of the sea-island structure does not become too large, allowing for the formation of microphase separation. Furthermore, by selecting an epoxy equivalent within this range, the size of the island structures can be controlled. The epoxy equivalent (g / mol) in the present invention can be calculated by adding hydrochloric acid to a predetermined mass of sample dissolved in 1,4-dioxane and back-titrating with aqueous sodium hydroxide solution.

[0067] Low molecular weight cyclic siloxanes are preferable because they can cause various problems such as contact failure. Component (B-1) preferably contains hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in a total amount of more than 0 ppm and 3,000 ppm or less, more preferably 0.1 to 2,000 ppm, and even more preferably 0.1 to 1,000 ppm.

[0068] The amounts of the low molecular weight cyclic siloxanes (D3 to D6) are values ​​determined by gas chromatography (GC) using a sample prepared by extracting and diluting component (B-1) with acetone. The term "greater than 0 ppm" refers to any peak detected by the above method, even if only a small amount.

[0069] In the present invention, the blending amount of component (B-1) is preferably 1 to 40 parts by mass, more preferably 10 to 30 parts by mass, and even more preferably 10 to 20 parts by mass, per 100 parts by mass of component (A). When the blending amount of component (B-1) is 40 parts by mass or less, the strength of the cured epoxy resin is not reduced, and adhesive strength is sufficient. Furthermore, the Tg and heat resistance are not reduced. Furthermore, when preparing the prepolymer (component (B)), the ratio of the number of moles of NH bonds in the aromatic amine curing agent (C-1) to the number of moles of epoxy groups in the urethane bond-containing polyorganosiloxane of general formula (1) of component (B-1) must be at least two times the number of moles, thereby eliminating the risk of gelation. On the other hand, when the blending amount is 1 part by mass or more, the desired effect of adding component (B-1) can be achieved.

[0070] [(C) Epoxy resin curing agent] The epoxy resin curing agent (C) in the epoxy resin composition of the present invention can be any known curing agent capable of reacting with and curing an epoxy resin. This curing agent is added to react the reactive functional groups (amino groups) in the curing agent molecule with the epoxy groups in component (A) to form a cured product with a three-dimensional crosslinked structure.

[0071] The component (C) is an aromatic amine curing agent (C-1) and a non-aromatic amine curing agent (C-2). Of these, the component (C-1) is blended as the prepolymer (B), which is a reaction product with the component (B-1).

[0072] In the present invention, the term "aromatic amine" refers to an amine in which an amino group is directly bonded to an aromatic ring, and the term "non-aromatic amine" refers to an amine in which an amino group is bonded to an aromatic ring via an alkylene group, or an alicyclic amine.

[0073] [(C-1) Aromatic amine curing agent] The aromatic amine curing agent (C-1) is preferably a compound represented by the following general formula (I) or the following general formula (II). [ka] (In the formula, R's are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R's are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and n represents the number of substituents and is an integer of 0 to 4.)

[0074] Specific examples of the (C-1) aromatic amine curing agent include aromatic diaminodiphenylmethane compounds such as 4,4'-diaminodiphenylmethane, 3,3'-diethyl-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetraethyl-4,4'-diaminodiphenylmethane, 2,4-diaminotoluene, 1,4-diaminobenzene, 1,3-diaminobenzene, etc. These can be used alone or in combination of two or more.

[0075] Other aromatic amine curing agents that can be used include aromatic polyamines that are generally commercially available, such as Kayahard AA (Nippon Kayaku Co., Ltd.), jER Cure WA (Mitsubishi Chemical Corporation), Curehard MED-J, and Heart Cure 10 (Kumiai Chemical Industry Co., Ltd.).

[0076] More preferred are aromatic diaminodiphenylmethane compounds such as 4,4'-diaminodiphenylmethane.

[0077] [(C-2) Non-aromatic amine curing agent] The non-aromatic amine curing agent (C-2) is preferably a compound of the following general formula (III) or the following general formula (IV). [ka] (In the formula, R's are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R's are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and n represents the number of substituents and is an integer of 0 to 4.)

[0078] (C-2) Non-aromatic amine curing agents include, for example, m-xylenediamine and derivatives thereof. Other examples include bis(aminomethyl)benzene and 1,3-bisaminomethylcyclohexane. Of these, 1,3-bis(aminomethyl)benzene is preferred.

[0079] Of the total amount of NH bonds in the components (C-1) and (C-2), the amount of NH bonds in the component (C-1) is preferably 30 to 70 mol %, more preferably 40 to 60 mol %. With such an epoxy resin composition, when preparing the prepolymer (B), a gel does not form due to a crosslinking reaction or high molecular weight, and handling is easy.

[0080] [(D) Filler] The epoxy resin composition of the present invention may further contain a (D) filler. Examples of the (D) filler include silicas such as fused silica, crystalline silica, and cristobalite, and metal oxides such as aluminum oxide, titanium oxide, and magnesium oxide. These fillers may be used alone or in combination of two or more. Among these, silicas are preferred from the viewpoints of availability and quality stability. The amount of the (D) filler to be added is preferably in the range of 1 to 25 parts by mass per 100 parts by mass of the total composition.

[0081] The average particle size is preferably 0.1 to 50 μm and can be selected depending on the application. The average particle size is a volume average particle size measured by laser diffraction.

[0082] The filler (D) is preferably surface-treated in advance with a coupling agent such as a silane coupling agent, etc. The amount of the coupling agent used for the surface treatment and the surface treatment method are not particularly limited.

[0083] [Other ingredients] The epoxy resin composition of the present invention may contain other additives as needed, such as reactive diluents, curing accelerators, flame retardants, ion trapping agents, antioxidants, adhesion promoters, colorants, and coupling agents.

[0084] [Method of producing epoxy resin composition] In the method for producing an epoxy resin composition of the present invention, for example, the epoxy resin composition can be obtained by simultaneously mixing, stirring, dissolving, and dispersing the (A), (B), and (C-2) components while heating them. Alternatively, the epoxy resin composition can be obtained by separately heating the (A), (B), and (C-2) components while mixing, stirring, dissolving, and dispersing them. Preferably, the (B-1) and (C-1) components are mixed, stirred, dissolved, and dispersed while heating them to prepare a prepolymer (B), and then the (A) and (C-2) components are added simultaneously to obtain an epoxy resin composition in which the (B) component is well dispersed. More preferably, the (B-1) and (C-1) components are mixed, stirred, dissolved, and dispersed while heating them to prepare a prepolymer (B), and then the (C-2) components are mixed, stirred, dissolved, and dispersed, and then the (A) component is added to obtain an epoxy resin composition in which the (B) component is well dispersed.

[0085] Component (D) and / or other additives may also be added as needed. Component (D) may be added to components (A), (B), and (C-2), and mixed, stirred, dissolved, and dispersed while simultaneously or separately undergoing heat treatment. Alternatively, components (B) and (C-2) may be mixed, stirred, dissolved, and dispersed while undergoing heat treatment, and then component (D) and / or other additives may be added simultaneously with component (A).

[0086] [Epoxy resin cured product] A second embodiment of the present invention is a cured epoxy resin product obtained by curing the epoxy resin composition described above. By curing and molding the product in a mold appropriate for the application, it can be provided as a highly tough cured product member for a variety of applications.

[0087] The curing conditions for the epoxy resin composition of the present invention are not particularly limited, but may be, for example, heating at a temperature of 60 to 200°C, preferably 80 to 180°C, for 30 minutes to 10 hours, preferably 1 to 5 hours. To efficiently carry out the reaction, heating may be performed, for example, in two to five stages, from low to high temperatures for the above-mentioned time. Taking into consideration adhesion to the resin, more preferably, heating at a temperature of 80 to 130°C for a predetermined time will yield a cured product with sufficient strength in order to prevent softening of the resin.

[0088] [Epoxy adhesive] A third embodiment of the present invention is an epoxy adhesive comprising the epoxy resin composition described above.

[0089] The epoxy resin composition used in the above-mentioned epoxy adhesive is preferably mixed in such a ratio that the ratio of the valence (number of moles) of the N-H bonds of the (C-1) and (C-2) components to the total valence (number of moles) of the epoxy groups of the (A) and (B-1) components is 0.8 to 1.2, and more preferably mixed in equal amounts.

[0090] [domain] As mentioned above, the epoxy resin composition of the present invention has poor compatibility between the organosiloxane moieties in the prepolymer (B) and the epoxy resin (A), resulting in the formation of a sea-island structure in which component (B) forms islands and component (A) forms the sea. The island components of this sea-island structure are commonly called domains, and controlling their amount and size can improve both the elongation and tensile shear strength of the cured epoxy resin. Unlike conventional methods, the epoxy resin composition of the present invention allows for control of the domain size of component (B). The domain size is preferably 50 μm or less, more preferably 10 μm or less, and even more preferably 5 μm or less.

[0091] In the present invention, the domain size is measured by observing the cured epoxy resin product of the present invention with a scanning electron microscope. A measurement sample is coated with platinum to a thickness of 0.02 μm to prevent static buildup, and is fixed to a sample stage with conductive carbon double-sided tape. The domain size in the present invention is the average diameter of the domains in an area of ​​35 × 47 μm observed at an accelerating voltage of 5 kV and a magnification of 2,000 times. [Example]

[0092] EXAMPLES The present invention will be specifically explained below using examples, comparative examples, synthesis examples, and comparative synthesis examples, but the present invention is not limited to these.

[0093] In the following examples, the epoxy resin (A) is Bisphenol A epoxy resin: Mitsubishi Chemical Corporation, product name: jER828EL (epoxy equivalent weight 186 g / mol) (Hereafter referred to as DGEBA.) (C) as an epoxy resin curing agent; (C-1) Aromatic amine curing agent: 4,4'-diaminodiphenylmethane (NH equivalent: 49.6 g / mol) manufactured by Tokyo Chemical Industry Co., Ltd. (Hereafter referred to as DDM.) (C-2) Non-aromatic amine curing agent: 1,3-bis(aminomethyl)benzene (NH equivalent: 34.0 g / mol) manufactured by Tokyo Chemical Industry Co., Ltd. (Hereafter referred to as mXDA.) The urethane bond-containing polyorganosiloxane of component (B-1) was synthesized by the method described in the following Synthesis Examples and Comparative Synthesis Examples.

[0094] [Synthesis example 1] (m=1) A 500 mL separable flask was charged with 91.95 g (0.827 mol NCO) of isophorone diisocyanate, equipped with a mechanical stirrer, a stirring blade, a Dimroth reflux tube, a nitrogen gas inlet, and a thermometer, and nitrogen gas was allowed to flow in. Next, 0.32 g (0.1% by mass) of K-KAT XK-640 (Kusumoto Chemicals Co., Ltd., bismuth carboxylate, 18% bismuth content) catalyst was added, and the internal temperature was raised to 60°C. Using a 300 mL dropping funnel, 200.00 g (0.413 mol OH, NCO / OH = 2.0) of 3-(2-hydroxyethoxy)propyldimethylsiloxy-terminated polydimethylsiloxane (n = 8, OH value 116 mg KOH / g) containing 64 ppm D3, 59 ppm D4, 23 ppm D5, and 226 ppm D6 was added over 30 minutes, followed by aging at 70°C for 3 hours. Next, 30.80 g (0.415 mol) of glycidol was added, and the mixture was aged at 70°C for 2 hours, yielding 319.17 g of a colorless, slightly cloudy viscous liquid represented by the following formula: Since the NCO / OH ratio is 2.0, m is 1. Low molecular weight cyclic siloxanes were extracted with 10 mL of acetone using tetradecane as an internal standard per 1 g of sample and measured by GC. The total amount of D3 to D6 was 305 ppm (D3: 54 ppm, D4: 52 ppm, D5: 16 ppm, D6: 183 ppm). The epoxy equivalent was 758 g / mol. [ka]

[0095] [Synthesis example 2] (m=2) A 500 mL separable flask was charged with 70.15 g (0.631 mol NCO) of isophorone diisocyanate, equipped with a mechanical stirrer, a stirring blade, a Dimroth reflux tube, a nitrogen gas inlet, and a thermometer, and nitrogen gas was allowed to flow in. Next, 0.25 g (0.1% by mass) of K-KAT XK-640 (Kusumoto Chemicals Co., Ltd., bismuth carboxylate, 18% bismuth content) catalyst was added, and the internal temperature was raised to 60°C. Using a 300 mL dropping funnel, 200.00 g (0.413 mol OH, NCO / OH = 1.5) of 3-(2-hydroxyethoxy)propyldimethylsiloxy-terminated polydimethylsiloxane (n = 8, OH value 116 mg KOH / g) containing 64 ppm D3, 59 ppm D4, 23 ppm D5, and 226 ppm D6 was added over 30 minutes, followed by aging at 70°C for 3 hours. Next, 15.72 g (0.212 mol) of glycidol was added, and the mixture was aged at 70°C for 2 hours, yielding 277.05 g of a colorless, slightly cloudy viscous liquid represented by the following formula: Since the NCO / OH ratio is 1.5, m is 2. Low molecular weight cyclic siloxanes were extracted with 10 mL of hexane using tetradecane as an internal standard per 1 g of sample and measured by GC. The total amount of D3 to D6 was 339 ppm (D3: 60 ppm, D4: 55 ppm, D5: 18 ppm, D6: 206 ppm). The epoxy equivalent was 1093 g / mol. [ka]

[0096] [Comparative synthesis example 1] (m=3) A 500 mL separable flask was charged with 61.25 g (0.551 mol NCO) of isophorone diisocyanate, equipped with a mechanical stirrer, a stirring blade, a Dimroth reflux tube, a nitrogen gas inlet, and a thermometer, and nitrogen gas was allowed to flow in. Next, 0.26 g (0.1% by mass) of K-KAT XK-640 (Kusumoto Chemicals Co., Ltd., bismuth carboxylate, 18% bismuth content) catalyst was added, and the internal temperature was raised to 60°C. Using a 300 mL dropping funnel, 200.00 g (0.413 mol OH, NCO / OH = 1.33) of 3-(2-hydroxyethoxy)propyldimethylsiloxy-terminated polydimethylsiloxane (n = 8, OH value 116 mg KOH / g) containing 64 ppm D3, 59 ppm D4, 23 ppm D5, and 226 ppm D6 was added over 30 minutes, followed by aging at 70°C for 3 hours. Next, 10.46 g (0.141 mol) of glycidol was added, and the mixture was aged at 70°C for 2 hours, yielding 266.50 g of a colorless, slightly cloudy viscous liquid represented by the following formula: Since the NCO / OH ratio is 1.33, m is 3. Low molecular weight cyclic siloxanes were extracted with 10 mL of hexane using tetradecane as an internal standard per 1 g of sample and measured by GC. The total amount of D3 to D6 was 348 ppm (D3: 62 ppm, D4: 58 ppm, D5: 18 ppm, D6: 210 ppm). The epoxy equivalent was 2180 g / mol. [ka]

[0097] Compositions of the examples and comparative examples were prepared using the above materials, and the aluminum cups containing the compositions were heated and cured in a thermostatic chamber at 100°C for 2 hours, and then at 110°C, 120°C, and 130°C for 30 minutes each in four stages. The temperature rise rate was 5°C / min, and the following evaluations were carried out.

[0098] [Domain size measurement] The cured product obtained above was measured under the following conditions, and the results are shown in Table 1. (Measurement conditions) Measurement sample: Platinum was vapor-deposited to a thickness of 0.02 μm to prevent static buildup, and the sample was fixed to the sample stage with conductive carbon double-sided tape. Measurement equipment: Field emission scanning electron microscope (JSM-6700F, manufactured by JEOL Ltd.) Ion sputtering equipment (JFC-1500, manufactured by JEOL Ltd.) Magnification: 2,000x Accelerating voltage: 5 kV

[0099] [Glass transition temperature (Tg)] The cured product obtained above was cut into test pieces measuring 30 mm long x 4.0 mm wide x 0.40 mm thick and measured using a UBM Rheogel-E40000 under the following conditions: temperature range -150 to 250°C, sinusoidal wave, heating rate 2.5°C / min, tensile mode, frequency 10 Hz. The peak top of the loss tangent (tanδ), which is the loss modulus (G") / storage modulus (G'), was taken as Tg (°C). The results are shown in Table 1.

[0100] [Tensile shear adhesion test] The adherend was immersed in acetone and ultrasonically cleaned for 30 minutes. Next, the adherend was polished using an electric sander equipped with #240 abrasive paper to remove the surface oxide film, and then immersed in acetone and ultrasonically cleaned for 30 minutes twice. A backing plate (25 mm long x 25 mm wide x 1.6 mm thick) was then attached to the adherend at a position 62.5 mm from the edge. The composition prepared in each example and comparative example was then applied to the adherend up to 12.5 mm from the edge, and another adherend was placed on top of it. The mixture was then heated at 120°C and 5 MPa for 2 hours using a hot press. A weight (weight: 1700 g, pressure: 960 Pa) was then placed on the test piece in a thermostatic chamber and heated at 100°C for 2 hours, and then at 110°C, 120°C, and 130°C for 30 minutes each to prepare a test piece. The heating rate was 5°C / min. After gradual cooling, the test piece was taken out and the resin protruding from the joint was removed with a cutter knife. The obtained test pieces were subjected to a tensile shear adhesion test using an AGS-X manufactured by Shimadzu Corporation at a head speed of 50 mm / min. The tensile shear strength and breaking elongation were averaged over 5 tests. The results are shown in Table 1.

[0101] [Example 1] DDM (0.206 g, 4.15 mmol NH) as component (C-1) and polyorganosiloxane (0.15 g, 0.20 mmol Epoxy) from Synthesis Example 1 as component (B-1) were separately heated and melted and added to an aluminum cup. The mixture was stirred on a hot plate at 100 °C for 25 minutes to prepare a prepolymer (NH / Epoxy = 20.99). Next, degassed DGEBA (1.50 g, 8.06 mmol Epoxy) as component (A) was placed in a separate aluminum cup and heated and melted on a hot plate at 100 °C to reduce viscosity. This melted DGEBA and mXDA (0.141 g, 4.15 mmol NH) as component (C-2) were sequentially added to the aluminum cup containing the prepolymer and heated and stirred for 2 minutes to prepare a composition (NH / Epoxy = 1.00). The compositions thus obtained were then subjected to the above evaluations, and the evaluation results are shown in Table 1.

[0102] [Examples 2 to 4] As component (C-1), DDM having an NH equivalent of 0.5 chemical equivalents relative to the total epoxy group content of the epoxy group-containing compounds (components (A) and (B-1)), and the polyorganosiloxane of Synthesis Example 1 as component (B-1) were separately heated and melted in the amounts shown in Table 1, added to an aluminum cup, and stirred on a hot plate at 100 °C for 25 minutes to prepare a prepolymer. Next, as component (A), degassed DGEBA in the amount shown in Table 1 was placed in a separate aluminum cup and heated on a hot plate at 100 °C to reduce viscosity. Then, as component (C-2), mXDA having an NH equivalent of 0.5 chemical equivalents relative to the total remaining epoxy group content was added to the aluminum cup containing the prepolymer in the amount shown in Table 1 and heated and stirred for 2 minutes. The previously heated and melted DGEBA was then added to this mixture, and the mixture was heated and stirred for 2 minutes to prepare a composition. The compositions thus obtained were then subjected to the above evaluations, and the evaluation results are shown in Table 1. The NH equivalent of the component (C-1) relative to the amount of epoxy groups in the component (B-1) (NH / epoxy) was 41.36 in Example 2, 20.99 in Example 3, and 10.75 in Example 4.

[0103] [Comparative Example 1] As the component (B-1), the polyorganosiloxane compound (0.15 g) of Synthesis Example 1, and as the component (C-1), DDM (0.41 g) with an NH equivalent of 1.0 chemical equivalent relative to the total epoxy group amount of the epoxy group-containing compound (component (A) and component (B-1)) were separately heated and melted, then added to an aluminum cup and stirred on a hot plate at 140 ° C for 15 minutes to prepare a prepolymer. Next, as the component (A), degassed DGEBA (1.50 g) was placed in another aluminum cup and heated on a hot plate at 140 ° C to reduce the viscosity. This DGEBA was added to the aluminum cup containing the prepolymer, heated and stirred for 2 minutes to prepare a composition. Since the resulting composition did not yield a cured product under the same conditions as in the examples, it was heated at 150°C for 2 hours and then at 180°C for another 2 hours as curing conditions. The temperature rise rate was 5°C / min. The evaluation results are shown in Table 1.

[0104] Comparative Example 2 Degassed DGEBA (1.50 g) as component (A) and the polyorganosiloxane compound (0.30 g) of Synthesis Example 1 as component (B-1) were placed in an aluminum cup and heated on a hot plate at 130°C to reduce viscosity. Next, DDM (0.42 g) was placed in a separate aluminum cup as component (C-1), with an NH equivalent of 1.0 relative to the total epoxy group content of the epoxy group-containing compounds (components (A) and (B-1)). The mixture was stirred on a hot plate at the same temperature until completely melted. This DDM was added to the aluminum cup containing DGEBA and the polyorganosiloxane compound of Synthesis Example 1 and stirred for 5 minutes to prepare a composition. Since the resulting composition did not yield a cured product under the same conditions as in the examples, it was heated at 150°C for 2 hours, followed by another 2 hours at 180°C. The heating rate was 5°C / min. The evaluation results are shown in Table 1.

[0105] Comparative Example 3 As component (A), degassed DGEBA (1.50 g) was placed in an aluminum cup and heated on a hot plate at 100 °C to reduce viscosity. Next, as component (C-2), mXDA (0.274 g) with an NH equivalent of 1.0 chemical equivalent relative to the total epoxy group content of the epoxy group-containing compound (component (A)) was placed in a separate aluminum cup and completely melted while stirring on a hot plate at 130 °C. The mXDA was then added to the aluminum cup containing DGEBA and stirred for 5 minutes to produce a composition. Thereafter, adhesive test pieces were prepared under the same conditions as in the examples, and the tensile shear strength was measured. The result was 10 MPa or less, and it was determined that this composition did not have enough strength. Therefore, other evaluation items were not carried out.

[0106] Comparative Example 4 As the component (B-1), the polyorganosiloxane compound (0.15 g) of Comparative Synthesis Example 1, and as the component (C-1), DDM (0.206 g) having an NH equivalent of 0.5 chemical equivalents relative to the total epoxy group content of the epoxy group-containing compounds (A) and (B-1) were separately heated and melted, then added to an aluminum cup and stirred on a hot plate at 100 ° C for 25 minutes to prepare a prepolymer. Next, as the component (A), degassed DGEBA was placed in another aluminum cup and heated on a hot plate at 100 ° C for the purpose of reducing the viscosity. This DGEBA (1.50 g) and as the component (C-2), mXDA (0.141 g) having an NH equivalent of 0.5 chemical equivalents relative to the total epoxy group content of the epoxy group-containing compounds (A) and (B-1) were sequentially added to the aluminum cup containing the prepolymer, and heated and stirred for 2 minutes to prepare a composition. Thereafter, the resulting composition was subjected to the same conditions as in the examples to produce a cured product. As a result, the resulting cured product had separated into island components of the sea-island structure that were visible on the surface, and a uniform cured product was not obtained. Therefore, further evaluation was not carried out.

[0107] Comparative Example 5 DDM (0.201 g, 4.05 mmol NH) as component (C-1) was separately heated and melted, then added to an aluminum cup and stirred on a hot plate at 100 °C for 25 minutes. Next, degassed DGEBA (1.50 g, 8.06 mmol epoxy) as component (A) was placed in a separate aluminum cup and heated on a hot plate at 100 °C to reduce viscosity. This DGEBA and mXDA (0.138 g, 4.06 mmol NH) as component (C-2) were then added sequentially to the aluminum cup containing DDM and heated and stirred for 2 minutes to produce the composition. The obtained compositions were then evaluated under the same conditions as in Examples 1 and 2. The evaluation results are shown in Table 1.

[0108] The evaluation results of the examples and comparative examples are shown in Table 1. [Table 1]

[0109] Despite the low curing temperature, all Examples showed increased strength and elongation in tensile shear adhesion tests compared to Comparative Examples. Furthermore, Comparative Examples 1 and 2, which did not contain component (C-2), failed to produce cured products under the curing conditions of the Examples, requiring higher temperature curing conditions. Comparative Example 3, which did not contain component (B), exhibited insufficient tensile shear strength. Comparative Example 4, which did not contain a specific urethane bond-containing polyorganosiloxane as component (B-1) in the (B) component, exhibited a cured product in which the island components of the sea-island structure were separated into sizes visible by appearance, preventing the production of a uniform cured product. Comparative Example 5, which did not contain component (B-1), failed to produce domains, resulting in poor tensile shear strength and elongation at break.

[0110] This confirmed that the epoxy resin composition, the cured product thereof, and the epoxy adhesive of the present invention exhibit the properties of increasing both elongation and tensile shear strength even when the curing temperature is lowered while controlling the domain size.

[0111] The present specification includes the following aspects. [1]: An epoxy resin composition, (A) an epoxy resin containing two or more epoxy groups in one molecule; (B) a prepolymer which is a reaction product of the following (B-1) and (C-1): (B-1) a urethane bond-containing polyorganosiloxane represented by the following general formula (1): [ka] (In the formula, R 1are each independently a group selected from an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, or a hydroxyl group; X are each independently an alkylene group having 1 to 10 carbon atoms; Y are each independently a group selected from an alkylene group having 5 to 30 carbon atoms, an arylene group having 6 to 30 carbon atoms, and an aralkylene group having 7 to 30 carbon atoms; Z are each independently an alkylene group having 1 to 20 carbon atoms, and the alkylene group in Y and Z may have one or more ether bonds in the molecular chain; n is an integer of 0 to 100; and m is 1 or 2. (C-1) aromatic amine curing agent: an amount such that the number of NH bonds in (C-1) is at least twice the number of epoxy groups in (B-1), and (C-2) Non-aromatic amine curing agent An epoxy resin composition comprising: [2]: The epoxy resin composition according to the above [1], wherein the component (A) is a bisphenol-type epoxy resin. [3]: The epoxy resin composition according to the above [1] or [2], wherein the polyorganosiloxane represented by the general formula (1) has a number average molecular weight of 500 to 100,000 in terms of polystyrene standard. [4]: The epoxy resin composition according to any one of [1] to [3] above, wherein the polyorganosiloxane represented by the general formula (1) has an epoxy equivalent of 300 to 5,000 g / mol. [5]: The epoxy resin composition according to any one of [1] to [4] above, wherein the component (B-1) contains hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in a total amount of 3,000 ppm or less. [6]: The epoxy resin composition according to any one of [1] to [5] above, wherein the NH bonds in the component (C-1) account for 30 to 70 mol % of the total amount of NH bonds in the components (C-1) and (C-2). [7]: The epoxy resin composition according to any one of [1] to [6] above, wherein the component (C-1) is a compound represented by the following general formula (I), general formula (II), or an aromatic polyamine: [ka] (In the formula, R's are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R's are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and n represents the number of substituents and is an integer of 0 to 4.) [8]: The epoxy resin composition according to [7] above, wherein the component (C-1) is 4,4'-diaminodiphenylmethane. [9]: The epoxy resin composition according to any one of [1] to [8] above, wherein the component (C-2) is represented by the following general formula (III) or general formula (IV): [ka] (In the formula, R's are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R's are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and n represents the number of substituents and is an integer of 0 to 4.)

[10] : The epoxy resin composition according to [9] above, wherein the component (C-2) is selected from m-xylylenediamine and its derivatives.

[11] : The epoxy resin composition according to any one of [1] to

[10] above, further comprising (D) a filler.

[12] : A cured epoxy resin product, characterized in that the cured epoxy resin product is obtained by curing any one of the epoxy resin compositions [1] to

[11] above.

[13] : An epoxy adhesive comprising any one of the epoxy resin compositions described above in [1] to

[11] .

[0112] The present invention is not limited to the above-described embodiments. The above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits similar effects is included within the technical scope of the present invention.

Claims

1. An epoxy resin composition comprising: (A) an epoxy resin containing two or more epoxy groups in one molecule; (B) a prepolymer which is a reaction product of the following (B-1) and (C-1): (B-1) a urethane bond-containing polyorganosiloxane represented by the following general formula (1): 【Chemistry 1】 (In the formula, R １ are each independently a group selected from an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aralkyl group having 7 to 12 carbon atoms, or a hydroxyl group; Xs are each independently an alkylene group having 1 to 10 carbon atoms; Ys are each independently a group selected from an alkylene group having 5 to 30 carbon atoms, an arylene group having 6 to 30 carbon atoms, and an aralkylene group having 7 to 30 carbon atoms; Zs are each independently an alkylene group having 1 to 20 carbon atoms, and the alkylene group in Y and Z may have one or more ether bonds in the molecular chain; n is an integer of 0 to 100; and m is 1 or 2. (C-1) aromatic amine curing agent: an amount such that the number of N—H bonds in (C-1) is at least twice the number of epoxy groups in (B-1), and (C-2) Non-aromatic amine curing agent An epoxy resin composition comprising:

2. 2. The epoxy resin composition according to claim 1, wherein the component (A) is a bisphenol-type epoxy resin.

3. 2. The epoxy resin composition according to claim 1, wherein the polyorganosiloxane represented by the general formula (1) has a number average molecular weight of 500 to 100,000 in terms of polystyrene standard.

4. 2. The epoxy resin composition according to claim 1, wherein the polyorganosiloxane represented by the general formula (1) has an epoxy equivalent of 300 to 5,000 g / mol.

5. 2. The epoxy resin composition according to claim 1, wherein the component (B-1) contains hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in a total amount of 3,000 ppm or less.

6. 2. The epoxy resin composition according to claim 1, wherein the N—H bonds in component (C-1) account for 30 to 70 mol % of the total N—H bonds in components (C-1) and (C-2).

7. 2. The epoxy resin composition according to claim 1, wherein the component (C-1) is a compound represented by the following general formula (I) or (II), or an aromatic polyamine: 【Chemistry 2】 (In the formula, R's are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; R's are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms; and n represents the number of substituents, and is an integer of 0 to 4.)

8. 8. The epoxy resin composition according to claim 7, wherein the component (C-1) is 4,4'-diaminodiphenylmethane.

9. 2. The epoxy resin composition according to claim 1, wherein the component (C-2) is represented by the following general formula (III) or general formula (IV): 【Transformation 3】 (In the formula, each R is independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; each R" is independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; and n represents the number of substituents and is an integer of 0 to 4.)

10. 10. The epoxy resin composition according to claim 9, wherein the component (C-2) is selected from m-xylenediamine and its derivatives.

11. 2. The epoxy resin composition according to claim 1, further comprising (D) a filler.

12. 12. A cured epoxy resin product, characterized in that the cured epoxy resin product is obtained by curing the epoxy resin composition according to any one of claims 1 to 11.

13. An epoxy adhesive comprising the epoxy resin composition according to any one of claims 1 to 11.

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