Reaction composition, epoxy resin curing agent, epoxy resin composition, and cured product thereof

Abstract

Provided are: a reaction composition which comprises a reaction product of xylylenediamine and a (meth)acrylamide derivative having only one (meth)acrylic group; and an epoxy resin curing agent, an epoxy resin composition, and a cured product thereof which each include the reaction composition.

Description

Reactive composition, epoxy resin curing agent, epoxy resin composition and cured product thereof

[0001] The present invention relates to a reaction composition, an epoxy resin curing agent, an epoxy resin composition, and a cured product thereof.

[0002] Polyamine compounds are known as a type of epoxy resin curing agent. Epoxy resin compositions using polyamine compounds as epoxy resin curing agents are used in the paint field, such as anticorrosion paints for ships, bridges, and land and sea steel structures, as well as in the civil engineering and construction fields, such as linings, reinforcing, and repair materials for concrete structures, flooring materials for buildings, linings for water and sewer systems, paving materials, and adhesives. Of these, it is important for epoxy resin compositions for paints to have good coating film appearance, water resistance, chemical resistance, and coating film properties.

[0003] Xylylenediamine, a type of aliphatic polyamine compound, is fast-curing when used as an epoxy resin curing agent, and is further characterized by excellent low-temperature curing properties, chemical resistance, etc. compared to other aliphatic polyamines. However, since xylylenediamine is prone to absorbing carbon dioxide and water vapor from the atmosphere to produce carbamates, coating films of epoxy resin compositions using xylylenediamine as an epoxy resin curing agent tend to be prone to whitening and have a poor appearance.

[0004] Xylylenediamine-modified epoxy resin curing agents have been investigated as a method for preventing the whitening of coating films and improving other properties. For example, Patent Document 1 discloses that an epoxy resin curing agent composition containing a polyamine compound, which is a reaction product of a compound having at least one glycidyl group per molecule with a diamine such as xylylenediamine, a specified polyether-modified polysiloxane, and a specified amino-modified polysiloxane, can solve the problem of whitening caused by reduced water resistance and resulting in poor appearance, and can provide an epoxy resin composition with excellent surface appearance such as transparency, drying properties (easy drying), adhesion to substrates, and water resistance. Patent Document 2 discloses that an aqueous epoxy resin composition containing an aqueous epoxy resin and a curing agent composition containing a reaction product of epichlorohydrin and xylylenediamine in a specified ratio has good workability and excellent coating adhesion and chemical resistance.

[0005] JP 2007-186693 A International Publication No. 2020 / 110601

[0006] Cured products of epoxy resin compositions tend to have poor adhesion to inorganic substances, particularly aluminum. Prior art left room for improvement in this regard. It is an object of the present invention to provide a novel reaction composition that, when used as an epoxy resin curing agent, can give cured epoxy resin products that have excellent adhesion to inorganic substances, particularly aluminum, and an epoxy resin curing agent and epoxy resin composition containing the reaction composition, as well as a cured product thereof.

[0007] The present inventors have found that the above-mentioned problems can be solved by a reaction composition containing a reaction product of xylylenediamine and a (meth)acrylamide derivative having only one (meth)acryl group. Specifically, the present invention relates to the following: [1] A reaction composition containing a reaction product of xylylenediamine and a (meth)acrylamide derivative having only one (meth)acryl group. [2] The reaction composition according to [1], wherein the reaction composition is obtained by reacting 0.8 to 1.8 moles of the (meth)acrylamide derivative with 1 mole of xylylenediamine. [3] The reaction composition according to [1] or [2], wherein the (meth)acrylamide derivative is at least one selected from the group consisting of N,N-dimethyl(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, and 4-(meth)acryloylmorpholine. [4] The reaction composition according to any one of [1] to [3], wherein the reaction product includes at least one reactant represented by the following general formulas (1) to (3): (In the formula, R １ is a hydrogen atom or a methyl group. ２ and R ３ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms which may have a hydroxyl group, or -(CH ２ ) ｎ -NR ４ R ５ (n is a number from 1 to 10, R ４ and R ５ are each independently a hydrogen atom or a methyl group. ２ and R ３ are groups which together form a ring structure. ２ and R ３ are not both hydrogen atoms.) [5] An epoxy resin curing agent containing the reaction composition according to any one of [1] to [4]. [6] An epoxy resin composition containing an epoxy resin and the epoxy resin curing agent according to [5]. [7] A cured product obtained by curing the epoxy resin composition according to [6].

[0008] According to the present invention, it is possible to provide a reaction composition which, when used as an epoxy resin curing agent, gives a cured epoxy resin product having excellent adhesion to inorganic substances, particularly aluminum, as well as an epoxy resin curing agent and an epoxy resin composition containing the reaction composition, and a cured product thereof.

[0009] [Reaction Composition] The reaction composition of the present invention comprises a reaction product of xylylenediamine and a (meth)acrylamide derivative having only one (meth)acryl group. In this specification, "a reaction composition comprising a reaction product of xylylenediamine and a (meth)acrylamide derivative having only one (meth)acryl group" refers to a reaction composition containing a product obtained by the reaction of xylylenediamine with the (meth)acrylamide derivative, that is, a reaction product (adduct) of the xylylenediamine and the (meth)acrylamide derivative. The reaction composition may contain unreacted raw materials, etc. In this specification, a (meth)acryl group refers to an acryl group or a methacryl group. In this specification, a (meth)acrylamide derivative refers to an acrylamide derivative or a methacrylamide derivative. Furthermore, acrylamide and methacrylamide are not included in (meth)acrylamide derivatives.

[0010] When the reaction composition of the present invention is used as an epoxy resin curing agent, a cured epoxy resin product with excellent adhesion to inorganic materials, particularly aluminum, is obtained. The reason why the reaction composition of the present invention achieves the above-mentioned effects is not clear, but it is thought to be as follows. The reaction composition of the present invention is a type of modified xylylenediamine. By modifying xylylenediamine with a (meth)acrylamide derivative, the molecular weight is increased and a modified product (reaction product) with an amide bond site introduced is obtained. As a result, it is thought that when this modified product is used as an epoxy resin curing agent, a cured epoxy resin product with excellent adhesion to inorganic materials, particularly aluminum, is obtained.

[0011] The xylylenediamine is at least one selected from the group consisting of orthoxylylenediamine, metaxylylenediamine, and paraxylylenediamine. From the viewpoint of improving the adhesion of the cured product of the resulting epoxy resin composition to inorganic substances when used as an epoxy resin curing agent, the xylylenediamine is preferably at least one selected from the group consisting of metaxylylenediamine and paraxylylenediamine, more preferably metaxylylenediamine or a mixture of metaxylylenediamine and paraxylylenediamine, and even more preferably metaxylylenediamine.

[0012] Examples of the (meth)acrylamide derivative having only one (meth)acryl group (hereinafter, also simply referred to as "(meth)acrylamide derivative") include compounds represented by the following general formula (I). (In the formula, R １ is a hydrogen atom or a methyl group. ２ and R ３ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms which may have a hydroxyl group, or -(CH ２ ) ｎ -NR ４ R ５ (n is a number from 1 to 10, R ４ and R ５ are each independently a hydrogen atom or a methyl group. ２ and R ３ are groups which together form a ring structure. ２ and R ３ cannot both become hydrogen atoms.)

[0013] In general formula (I), R １ is preferably a hydrogen atom from the viewpoint of improving the adhesiveness of the cured product of the epoxy resin composition obtained when the reaction composition is used as an epoxy resin curing agent to inorganic substances.

[0014] R in general formula (I) ２ and R ３In the formula (I), examples of the alkyl group having 1 to 8 carbon atoms which may have a hydroxy group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a hydroxymethyl group, a hydroxyethyl group, a hydroxypropyl group, a hydroxybutyl group, a hydroxypentyl group, a hydroxyhexyl group, a hydroxyheptyl group, and a hydroxyoctyl group. Among these, from the viewpoint of improving the adhesion to inorganic substances of the cured product of the epoxy resin composition obtained when the reaction composition is used as an epoxy resin curing agent, preferred are alkyl groups having 1 to 6 carbon atoms which may have a hydroxy group, more preferred are alkyl groups having 1 to 4 carbon atoms which may have a hydroxy group, and even more preferred are methyl groups, ethyl groups, and hydroxyethyl groups.

[0015] R in general formula (I) ２ and R ３ In the -(CH ２ ) ｎ -NR ４ R ５ (n is a number from 1 to 10, R ４ and R ５ are each independently a hydrogen atom or a methyl group), n is preferably 2 to 6, more preferably 2 to 4, and R ４ and R ５ and are preferably both methyl groups.

[0016] R in general formula (I) ２ and R ３ are a group in which they together form a ring structure, the ring structure is preferably a 5- or 6-membered ring, more preferably a 6-membered ring, from the viewpoint of stability. The ring structure may contain a heteroatom such as a nitrogen atom or an oxygen atom as a ring member, and preferably contains an oxygen atom. The ring structure is more preferably a morpholine ring, from the viewpoint of improving the adhesion of the cured product of the obtained epoxy resin composition to inorganic substances when the reaction composition is used as an epoxy resin curing agent.

[0017] Specific examples of the (meth)acrylamide derivative include N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, 4-(meth)acryloylmorpholine, etc. Among the above, from the viewpoint of improving the adhesion to inorganic substances of the cured product of the obtained epoxy resin composition when the reaction composition is used as an epoxy resin curing agent, the (meth)acrylamide derivative is preferably at least one selected from the group consisting of N,N-dimethyl(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, and 4-(meth)acryloylmorpholine, more preferably at least one selected from the group consisting of N,N-dimethylacrylamide, N-hydroxyethylacrylamide, and 4-acryloylmorpholine, and even more preferably at least one selected from the group consisting of N-hydroxyethylacrylamide and 4-acryloylmorpholine.

[0018] The reaction product of xylylenediamine and a (meth)acrylamide derivative having only one (meth)acryl group (hereinafter simply referred to as "reactant") preferably includes at least one of the reaction products represented by the following general formulas (1) to (3), and more preferably includes the reaction product represented by the following general formula (1). This is because all of the reaction products represented by the following general formulas (1) to (3) have a hydrogen atom (active hydrogen) bonded to a nitrogen atom and act effectively as an epoxy resin curing agent. (In the formula, R １ is a hydrogen atom or a methyl group. ２ and R ３ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms which may have a hydroxyl group, or -(CH ２ ) ｎ -NR ４ R ５ (n is a number from 1 to 10, R ４ and R ５ are each independently a hydrogen atom or a methyl group. ２ and R３ are groups which together form a ring structure. ２ and R ３ and R in the general formulae (1) to (3) cannot both be hydrogen atoms. １ ~R ３ and the preferred embodiments thereof are the same as those described above.

[0019] The reactant represented by the general formula (1) is a reactant obtained by reacting xylylenediamine with the (meth)acrylamide derivative in a molar ratio of 1:1 (hereinafter also referred to as "mono-adduct"), while the reactants represented by the general formulas (2) and (3) are reactants obtained by reacting xylylenediamine with the (meth)acrylamide derivative in a molar ratio of 1:2 (hereinafter also referred to as "di-adduct").

[0020] The reaction composition may further contain a reaction product (a tri-adduct) obtained by reacting xylylenediamine with the (meth)acrylamide derivative in a molar ratio of 1:3, and a reaction product (a tetra-adduct) obtained by reacting xylylenediamine with the (meth)acrylamide derivative in a molar ratio of 1:4. However, from the viewpoint of the reaction composition effectively acting as an epoxy resin curing agent, it is preferable that the reaction composition contains at least the reaction product represented by general formula (1).

[0021] The content of the reaction product of xylylenediamine and a (meth)acrylamide derivative having only one (meth)acryl group in the reaction composition is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more, but 100% by mass or less, from the viewpoint of improving the adhesion to inorganic substances of the cured product of the obtained epoxy resin composition when the reaction composition is used as an epoxy resin curing agent.

[0022] The reaction composition may contain by-products other than the reaction products, unreacted raw materials such as xylylenediamine, etc. However, from the viewpoint of improving the adhesion of the cured product of the epoxy resin composition obtained when the reaction composition is used as an epoxy resin curing agent to inorganic substances, the content of xylylenediamine in the reaction composition is preferably small, and is preferably 30 mass% or less.

[0023] The content of the unreacted raw material xylylenediamine in the reaction composition can be measured by gas chromatography (GC) analysis.

[0024] <Viscosity> From the viewpoint of improving handleability, the viscosity of the reaction composition at 25°C is preferably 50 Pa s or less, more preferably 30 Pa s or less, and even more preferably 20 Pa s or less. There is no particular lower limit for the viscosity, but it is preferably 10 mPa s or more, more preferably 30 mPa s or more. The viscosity of the reaction composition at 25°C can be measured using an E-type viscometer, specifically by the method described in the examples.

[0025] <Active Hydrogen Equivalent (AHEW)> The active hydrogen equivalent (AHEW) of the reaction composition is preferably 75 or more from the viewpoint of fast curing when the reaction composition is used as an epoxy resin curing agent and improving the adhesion of the resulting cured epoxy resin composition to inorganic substances, and from the viewpoint of improving curing properties, it is preferably 150 or less, more preferably 120 or less, and even more preferably 100 or less. In this specification, the active hydrogen equivalent (hereinafter also referred to as "AHEW") refers to the mass of the reaction composition per mole of active hydrogen derived from amino groups. The AHEW of the reaction composition can be calculated from the amine value of the reaction composition, and specifically can be determined by the method described in the Examples.

[0026] <Method for Producing Reaction Composition> The reaction composition of the present invention can be produced, for example, by subjecting xylylenediamine and the (meth)acrylamide derivative to an addition reaction under heated conditions. From the viewpoint of increasing the content of the reaction product (mono-adduct) obtained by reacting xylylenediamine and the (meth)acrylamide derivative at a molar ratio of 1:1 in the reaction composition, the reaction composition is obtained by reacting preferably 0.8 to 1.8 moles, more preferably 0.9 to 1.8 moles, even more preferably 1.0 to 1.5 moles, and even more preferably 1.0 to 1.3 moles of the (meth)acrylamide derivative with 1 mole of xylylenediamine. The molar amounts referred to here refer to the molar amounts of the xylylenediamine and (meth)acrylamide derivative charged during the reaction.

[0027] The reaction between xylylenediamine and the (meth)acrylamide derivative is preferably carried out under heated stirring conditions. The addition reaction can be carried out, for example, by charging xylylenediamine into a reaction vessel, adding the (meth)acrylamide derivative dropwise with stirring, and, after completion of the dropwise addition, raising the temperature to preferably 50 to 150°C, more preferably 70 to 130°C, and carrying out the reaction for 0.5 to 12 hours. The addition reaction can be carried out in a reaction solvent, but is preferably carried out without a solvent from the viewpoint of improving the reaction yield. The addition reaction is also preferably carried out under an inert gas atmosphere such as nitrogen gas. After completion of the reaction, the resulting reaction solution may be used as is as the reaction composition of the present invention, or the reaction solution may be purified by distillation to remove unreacted raw materials.

[0028] [Epoxy Resin Curing Agent] The epoxy resin curing agent of the present invention contains the reaction composition of the present invention. When the epoxy resin curing agent is used in an epoxy resin composition, a cured epoxy resin product having high adhesion to inorganic substances can be formed. From the viewpoint of improving the adhesion to inorganic substances of the resulting cured epoxy resin composition, the content of the reaction composition in the epoxy resin curing agent is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, still more preferably 80% by mass or more, and even more preferably 90% by mass or more, and 100% by mass or less.

[0029] The epoxy resin curing agent of the present invention may contain other curing agent components in addition to the reaction composition. In this specification, the term "curing agent component" refers to a component contained in the epoxy resin curing agent that has two or more active hydrogens capable of reacting with the epoxy groups in the epoxy resin. Examples of such other curing agent components include amine-based curing agents, phenol-based curing agents, and acid anhydride-based curing agents, with amine-based curing agents being preferred from the viewpoint of rapid curing. Examples of amine-based curing agents include polyamine compounds or modified products thereof other than the reaction composition. The polyamine compound is not particularly limited as long as it has at least two amino groups in its molecule.Examples of the polyamine compound or a modified product thereof include chain aliphatic polyamine compounds such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexamethylenediamine, 2-methylpentamethylenediamine, and trimethylhexamethylenediamine; 1,2-bis(aminomethyl)cyclohexane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, menthenediamine, isophoronediamine, norbornanediamine, tricyclodecanediamine, adamantanediamine, diaminocyclohexane, 1,4-diamino-2-methylcyclohexane, 1,4-diamino-3,6-diethylcyclohexane, diaminodiethylmethylcyclohexane, and 3,3'-dimethyl-4,4'-diaminodicyclohexyl Examples of suitable polyamine compounds include polyamine compounds having an alicyclic structure such as methane and 4,4'-diaminodicyclohexylmethane; polyamine compounds having an aromatic ring such as orthoxylylenediamine, metaxylylenediamine, and paraxylylenediamine, phenylenediamine, diaminodiphenylmethane, and diaminodiphenylsulfone; polyamine compounds having a heterocyclic structure such as N-aminomethylpiperazine and N-aminoethylpiperazine; polyetherpolyamine compounds; reaction products obtained by reacting the above polyamine compounds with an epoxy compound having at least one epoxy group, an unsaturated hydrocarbon compound, a carboxylic acid or a derivative thereof, or the like; Mannich reaction products obtained by reacting the above polyamine compounds with a phenol compound and an aldehyde compound; and ketimines (ketimines) obtained by reacting the above polyamine compounds with a ketone compound. These compounds may be used alone or in combination of two or more.

[0030] When other curing agent components are used, the content of the other curing agent components in the epoxy resin curing agent is preferably 1% by mass or more, more preferably 5% by mass or more. The upper limit of the content may be within a range that does not impair the effects of the present invention, and is preferably 50% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less, still more preferably 20% by mass or less, and even more preferably 10% by mass or less.

[0031] The epoxy resin curing agent of the present invention may further contain known curing accelerators, non-reactive diluents, etc. Examples of curing accelerators include phenolic compounds, organic acids, organic acid salts, tertiary amines, quaternary ammonium salts, imidazoles, organic phosphorus compounds, quaternary phosphonium salts, diazabicycloalkenes, organometallic salt compounds, boron compounds, and metal halides. Examples of non-reactive diluents include benzyl alcohol, furfuryl alcohol, tetrahydrofurfuryl alcohol, and aromatic hydrocarbon formaldehyde resins, and one or more of these can be used.

[0032] <Active Hydrogen Equivalent Weight (AHEW)> The active hydrogen equivalent weight (AHEW) of the epoxy resin curing agent is preferably 50 or more, more preferably 60 or more, and even more preferably 75 or more, from the viewpoint of fast curing properties when the reaction composition is used as an epoxy resin curing agent and improving the adhesion of the resulting cured product of the epoxy resin composition to inorganic substances, and from the viewpoint of improving curing properties, it is preferably 300 or less, more preferably 200 or less, even more preferably 150 or less, still more preferably 120 or less, and even more preferably 100 or less. The AHEW of the epoxy resin curing agent can be calculated in the same manner as for the AHEW of the reaction composition.

[0033] [Epoxy Resin Composition] The epoxy resin composition of the present invention contains an epoxy resin and the epoxy resin curing agent. A cured product of the epoxy resin composition has excellent adhesion to inorganic materials, particularly aluminum.

[0034] <Epoxy Resin> The epoxy resin, which is the main component of the epoxy resin composition, may be any of a saturated or unsaturated aliphatic compound, an alicyclic compound, an aromatic compound, and a heterocyclic compound. From the viewpoint of improving the curing rate and the adhesiveness of the resulting cured product to inorganic substances, an epoxy resin containing an aromatic ring or an alicyclic structure in the molecule is preferred. Specific examples of the epoxy resin include at least one resin selected from the group consisting of epoxy resins having a glycidylamino group derived from meta-xylylenediamine, epoxy resins having a glycidylamino group derived from para-xylylenediamine, epoxy resins having a glycidylamino group derived from 1,3-bis(aminomethyl)cyclohexane, epoxy resins having a glycidylamino group derived from 1,4-bis(aminomethyl)cyclohexane, epoxy resins having a glycidylamino group derived from diaminodiphenylmethane, epoxy resins having a glycidylamino group and / or a glycidyloxy group derived from para-aminophenol, epoxy resins having a glycidyloxy group derived from bisphenol A, epoxy resins having a glycidyloxy group derived from bisphenol F, epoxy resins having a glycidyloxy group derived from hydrogenated bisphenol A, epoxy resins having a glycidyloxy group derived from hydrogenated bisphenol F, epoxy resins having a glycidyloxy group derived from phenol novolac, and epoxy resins having a glycidyloxy group derived from resorcinol. The above epoxy resins may be used in combination of two or more kinds.

[0035] Among the above, from the viewpoints of improving the curing rate and improving the adhesion of the resulting cured product to inorganic substances, epoxy resins having at least one selected from the group consisting of epoxy resins having glycidylamino groups derived from meta-xylylenediamine, epoxy resins having glycidylamino groups derived from para-xylylenediamine, epoxy resins having glycidyloxy groups derived from bisphenol A, and epoxy resins having glycidyloxy groups derived from bisphenol F are preferred as the main component, and from the viewpoints of improving the curing rate, improving the adhesion of the resulting cured product to inorganic substances, availability, and economy, epoxy resins having glycidyloxy groups derived from bisphenol A as the main component are more preferred. Note that the term "main component" as used herein means that other components may be included within the scope of the present invention, and preferably means 50 to 100 mass%, more preferably 70 to 100 mass%, and even more preferably 90 to 100 mass% of the total.

[0036] The epoxy resin as the base resin may contain a reactive diluent other than the above-mentioned epoxy resin from the viewpoint of improving handleability. Examples of the reactive diluent include low-molecular-weight compounds having at least one epoxy group, such as aromatic monoglycidyl ethers such as phenyl glycidyl ether and cresyl glycidyl ether; alkyl monoglycidyl ethers such as butyl glycidyl ether, hexyl glycidyl ether, octyl glycidyl ether, decyl glycidyl ether, lauryl glycidyl ether, and tetradecyl glycidyl ether; and diglycidyl ethers of aliphatic diols such as 1,3-propanediol diglycidyl ether, 1,4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, and 1,6-hexanediol diglycidyl ether. The above-mentioned reactive diluents can be used alone or in combination of two or more.

[0037] The content ratio of the epoxy resin to the epoxy resin curing agent in the epoxy resin composition of the present invention is such that the ratio of the number of active hydrogens derived from amino groups in the epoxy resin curing agent to the number of epoxy groups in the epoxy resin (number of active hydrogens derived from amino groups in the epoxy resin curing agent / number of epoxy groups in the epoxy resin) is preferably 1 / 0.5 to 1 / 2, more preferably 1 / 0.75 to 1 / 1.5, and even more preferably 1 / 0.8 to 1 / 1.2.

[0038] The contents of the epoxy resin and epoxy resin curing agent in the epoxy resin composition are not limited as long as the ratio of the number of active hydrogen atoms derived from amino groups in the epoxy resin curing agent to the number of epoxy groups in the epoxy resin falls within the above-mentioned range. However, from the viewpoint of improving the curing rate and improving the adhesion of the obtained cured product to inorganic substances, the contents are preferably within the following ranges.

[0039] The content of the epoxy resin in the epoxy resin composition is preferably 40% by mass or more, more preferably 50% by mass or more, and even more preferably 60% by mass or more, and is preferably 80% by mass or less, and more preferably 75% by mass or less.

[0040] The content of the epoxy resin curing agent in the epoxy resin composition is preferably 20% by mass or more, more preferably 25% by mass or more, and preferably 60% by mass or less, more preferably 50% by mass or less, and even more preferably 40% by mass or less. The content of the epoxy resin curing agent in the epoxy resin composition is preferably 20 to 60 parts by mass, more preferably 30 to 60 parts by mass, and even more preferably 40 to 60 parts by mass, per 100 parts by mass of the epoxy resin as the main component.

[0041] From the viewpoint of improving the adhesion of the resulting cured product to inorganic substances, the total content of the epoxy resin and the epoxy resin curing agent in the epoxy resin composition is preferably 40% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, still more preferably 70% by mass or more, still more preferably 80% by mass or more, and still more preferably 90% by mass or more, but 100% by mass or less.

[0042] The epoxy resin composition of the present invention may further contain other components such as modifying components such as fillers and plasticizers, flow-adjusting components such as thixotropic agents, pigments, leveling agents, tackifiers, and elastomer fine particles, depending on the intended use.

[0043] <Method for producing epoxy resin composition> There is no particular limitation on the method for producing the epoxy resin composition of the present invention, and the composition can be produced by mixing the epoxy resin, the epoxy resin curing agent, and, if necessary, other components using known methods and devices. There is also no particular limitation on the order in which the components contained in the epoxy resin composition are mixed. The epoxy resin curing agent may be prepared and then mixed with the epoxy resin, or the components constituting the epoxy resin curing agent and other components may be simultaneously mixed with the epoxy resin to prepare the composition.

[0044] [Cured Product] A cured product of the epoxy resin composition of the present invention (hereinafter also simply referred to as "cured product of the present invention") is obtained by curing the epoxy resin composition. The curing conditions for the epoxy resin composition are appropriately selected depending on the application and form, and are not particularly limited. For example, the curing temperature of the epoxy resin composition can be selected in the range of 10 to 150°C, and the curing time can be selected in the range of 0.5 minutes to 7 days. The form of the cured product of the present invention is also not particularly limited, and can be selected depending on the application. From the viewpoint of being able to form an epoxy resin cured product that has excellent adhesion to inorganic substances, particularly aluminum, it is preferable that the cured product of the epoxy resin composition be in the form of a film or plate.

[0045] <Applications> The epoxy resin composition of the present invention can form a cured epoxy resin product having excellent adhesion to inorganic substances, and therefore can be used in a wide range of applications, such as: paints or adhesives for concrete, cement mortar, metal, glass, etc.; pressure-sensitive adhesives for labels, wallpaper, flooring materials; fiber treatment agents for glass fibers, carbon fibers, and metal fibers; building materials such as sealants, cement admixtures, and waterproofing materials; and others.

[0046] The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples. The amino compositions were analyzed and evaluated by the following methods.

[0047] <Gas Chromatography (GC) Analysis> The amount of metaxylylenediamine remaining in the reaction composition was analyzed by GC analysis (composition analysis of comparative reaction composition F in Comparative Example 3). The GC measurement conditions were as follows: Apparatus: "7890B GC" manufactured by Agilent Technologies, Inc. Column: "CP-Sil 8 CB for Amines" manufactured by Agilent Technologies, Inc. (length 30 m, film thickness 0.25 μm, inner diameter 0.25 mm) Column temperature: 40°C for 10 minutes → 20°C / minute temperature increase → 250°C for 10 minutes → 20°C / minute temperature increase → 300°C for 10 minutes Carrier gas: Helium Carrier gas flow rate: 2.2553 mL / min Inlet pressure: 22.474 psi (constant pressure mode) Detector: FID Inlet temperature: 250°C Detector temperature: 310°C

[0048] <FD-MS Analysis> The conditions for measuring the reaction composition by field desorption mass spectrometry (FD-MS) are as follows. Measuring device; AccuTOF GCV 4G (JMS-T100GCV) JEOL Ionization mode: Field Desorption (Positive) Range: m / z=30-800 Emitter Current: 0mA ~ 40mA 51.2mA / min Resolution: 8000 (at m / z=501.9711 (C9F20N)) Counter electrode Voltage: -10kV Detector Voltage: 2000V Sampling interval: 0.25ns Recording interval: 0.5s Drift compensation: m / z=501.9711 (C ９ F ２０ N)

[0049] < 1 H-NMR analysis of reaction composition 1 The H-NMR measurement conditions were as follows: Nuclear magnetic resonance spectrometer: AVANCEIII-500 manufactured by Bruker Biospin Co., Ltd. Probe: 5 mmφ double resonance multinuclear probe (BBFO Plus Smart probe) Deuterated solvent: deuterated chloroform Measurement nucleus: 1H Measurement temperature: room temperature

[0050] <Viscosity> The viscosity of the reactive composition (curing agent) at 25°C was measured using an E-type viscometer "TVE-35H Cone Plate Type Viscometer" manufactured by Toki Sangyo Co., Ltd. In Table 1, the viscosity of Amine D (MXDA) is the value measured at 20°C.

[0051] <Active Hydrogen Equivalent Weight (AHEW)> The AHEW of the reactive composition (curing agent) was calculated from the results of determining the total amine value and secondary and tertiary amine values ​​using an automatic potentiometric titrator "AT-710S" manufactured by Kyoto Electronics Manufacturing Co., Ltd. The total amine value was measured using a 0.1 mol / L perchloric acid / acetic acid solution (manufactured by Kanto Chemical Co., Ltd.), and the secondary and tertiary amine values ​​were measured using 0.1 mol / L hydrochloric acid (2-propanol). Note that in Table 1, the AHEW of some of the curing agents is shown as a theoretical value.

[0052] <Adhesion Strength to Aluminum Substrate> Test specimens having a shape specified in JIS K6851:1994 were prepared using the method described below. The epoxy resin composition of each example was applied to one side of an aluminum substrate ("A1050P" manufactured by Standard Test Piece) measuring 25 mm x 100 mm x 1.6 mm thick using a wooden spatula (composition coating thickness: 200 μm). This was then heat-cured for 1 hour in a hot air dryer set at 120°C to prepare test specimens having a cured epoxy resin composition layer formed on one side of the aluminum substrate. Next, using the test specimens, a tensile shear test (n=3) was performed using an autograph manufactured by Shimadzu Corporation in accordance with the method of JIS K6851:1994, at a temperature of 23°C and 50% RH, at a stroke speed of 1 mm / min. The breaking strength (maximum load, unit: N) when the cured layer peeled from the substrate was measured based on the shear area (unit: mm ２ ) is shown in Table 1 as the adhesive strength.

[0053] The components used in the following examples and comparative examples are as follows: MXDA: metaxylylenediamine, manufactured by Mitsubishi Gas Chemical Co., Inc. HEAA: N-hydroxyethylacrylamide, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. ACMO: 4-acryloylmorpholine, manufactured by Tokyo Chemical Industry Co., Ltd. DMAA: N,N-dimethylacrylamide, manufactured by Tokyo Chemical Industry Co., Ltd. G-328: reaction product of metaxylylenediamine and epichlorohydrin, "Gaskamine 328" manufactured by Mitsubishi Gas Chemical Co., Inc. BAL: benzaldehyde, manufactured by Tokyo Chemical Industry Co., Ltd.

[0054] Example 1 (Production and Evaluation of Reaction Composition A Comprising a Reaction Product of MXDA and HEAA) (Production of Reaction Composition A) 40.8 g (0.3 mol) of metaxylylenediamine (MXDA) was charged into a separable flask with an internal volume of 300 ml equipped with a stirrer, a thermometer, a nitrogen inlet tube, a dropping funnel, and a condenser, and 34.5 g (0.3 mol) of N-hydroxyethylacrylamide (HEAA) was added dropwise over 60 minutes under a nitrogen stream with stirring. After completion of the dropwise addition, the temperature was raised to 70°C and the reaction was carried out for 120 minutes. The temperature was further raised to 100°C and the mixture was stirred for 30 minutes to obtain a reaction composition A comprising a reaction product of MXDA and HEAA.

[0055] The obtained reaction composition A was analyzed by FD-MS and １ H-NMR analysis was performed. As a result of FD-MS analysis, peaks corresponding to the compound represented by the following formula (1A) (mono-adduct), the compound represented by the following formula (2A) (di-adduct), the compound represented by the following formula (3A) (di-adduct), and the compound represented by the following formula (4A) (tri-adduct) were detected in addition to the unreacted starting material meta-xylylenediamine. Specifically, the peaks corresponding to each compound were identified as follows: m / z = 137.10: metaxylylenediamine (Mw 136.2) m / z = 252.15: compound represented by the following formula (1A) (Mw 251.33) m / z = 367.20: compounds represented by the following formulas (2A) and (3A) (Mw 366.46) m / z = 482.26: compound represented by the following formula (4A) (Mw 481.59) m / z = 503.29: ionized product of the dimer of the compound represented by the following formula (1A)

[0056] １ H-NMR chemical shift: δ 7.33-7.10 ppm (m, -C ６ H ４ -), 3.92ppm (s, -NH ２ -CH ２ -C ６ H ４ -), 3.87ppm (s, -NH ２ -CH ２ -C ６ H ４ -), 3.80ppm (d, J=9.0Hz, -NH-CH ２ -C ６ H ４ -), 3.68 (dt, J=10Hz, 5Hz, -NH-CH ２ -CH ２ -), 3.43-3.34ppm (m, -CH ２ -CH ２ -CO-), 2.94ppm (t, J=5.75Hz, -NH-CH ２ -CH ２ -), 2.41ppm (td, J=5.75Hz, 3.0Hz, -CH ２ -CH ２ -OH), 2.17ppm (br, -CH ２ -NH-CO-, -CH ２ -NH-CH ２ -)

[0057] Furthermore, 0.1 g of the obtained reaction composition A was dissolved in 1 g of methanol, and the reaction composition was analyzed by GC analysis under the above conditions. The content of MXDA in reaction composition A was 19.7 mass %.

[0058] (Evaluation of Reaction Composition A) The viscosity and AHEW were measured by the above-described methods using the obtained reaction composition A. Furthermore, using reaction composition A as a curing agent, epoxy resin compositions were prepared and evaluated by the following methods.

[0059] [Preparation and Evaluation of Epoxy Resin Compositions] A liquid epoxy resin having glycidyloxy groups derived from bisphenol A ("jER828" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent weight 186 g / equivalent) was used as the base epoxy resin, and the above-mentioned reaction composition A was used as the epoxy resin curing agent. The epoxy resin and epoxy resin curing agent were blended in the amounts shown in Table 1 and stirred and mixed at 23°C to prepare epoxy resin compositions. The ratio of the number of active hydrogens in the epoxy resin curing agent to the number of epoxy groups in the base epoxy resin (number of active hydrogens in the epoxy resin curing agent / number of epoxy groups in the base epoxy resin) was adjusted to 1 / 1. The resulting epoxy resin compositions were used to evaluate the adhesive strength to aluminum substrates using the method described above. The results are shown in Table 1.

[0060] Example 2 (Production and Evaluation of Reaction Composition B Containing a Reaction Product of MXDA and ACMO) (Production of Reaction Composition B) Reaction composition B was produced in the same manner as in Example 1, except that 42.4 g (0.3 mol) of 4-acryloylmorpholine (ACMO) was used instead of HEAA. The obtained reaction composition B was analyzed by FD-MS and １ H-NMR analysis was performed. As a result of FD-MS analysis, peaks corresponding to the compound represented by the following formula (1B) (mono-adduct), the compound represented by the following formula (2B) (di-adduct), the compound represented by the following formula (3B) (di-adduct), and the compound represented by the following formula (4B) (tri-adduct) were detected. Specifically, the peaks corresponding to each compound were identified as follows: m / z = 278.19: Compound represented by the following formula (1B) (Mw 277.37) m / z = 419.27: Compounds represented by the following formulas (2B) and (3B) (Mw 418.26) m / z = 555.37: Ionized product of the dimer of the compound represented by the following formula (1B) m / z = 560.34: Compound represented by the following formula (4B) (Mw 559.34) m / z = 696.45: Ionized product of the heterodimer of the 1-adduct-2-adduct

[0061] １ H-NMR chemical shift: δ 7.34-7.07 ppm (m, -C ６ ​H ４ -), 3.87ppm (d, J=8.5Hz, -NH ２ -CH ２ -C ６ H ４ -), 3.80ppm (d, J=7.5Hz, -NH-CH ２ -C ６ H ４ -), 3.67-3.63ppm (m, -CH ２ -CH ２ -O-), 3.63-3.56ppm (m, -N-CH ２ -O-), 3.46-3.42ppm (m, -N-CH ２ -O-), 2.91ppm (dt, J=6.25Hz, 3.0Hz, -NH-CH ２ -CH ２ -), 2.53ppm (dt, J=6.25Hz, 2.0Hz, -CH ２ -CH ２ -CO-), 1.78ppm (br, -CH ２ -NH-CH ２ -)

[0062] Furthermore, 0.1 g of the obtained reaction composition B was dissolved in 1 g of methanol, and the reaction composition was analyzed by GC analysis under the above conditions. The content of MXDA in reaction composition B was 23.1 mass %.

[0063] (Evaluation of Reaction Composition B, Preparation and Evaluation of Epoxy Resin Compositions) Evaluation of reaction composition B, and preparation and evaluation of epoxy resin compositions having the formulations shown in Table 1 were carried out in the same manner as in Example 1, except that reaction composition B was used instead of reaction composition A. The results are shown in Table 1.

[0064] Example 3 (Production and Evaluation of Reaction Composition C Containing a Reaction Product of MXDA and DMAA) (Production of Reaction Composition C) Reaction composition C was produced in the same manner as in Example 1, except that the amount of metaxylylenediamine charged in Example 1 was changed to 33.0 g (0.24 mol) and 24.0 g (0.24 mol) of N,N-dimethylacrylamide (DMAA) was used instead of HEAA. The obtained reaction composition C was analyzed by FD-MS and １H-NMR analysis was carried out. As a result of FD-MS analysis, peaks corresponding to the compound represented by the following formula (1C) (mono-adduct), the compound represented by the following formula (2C) (di-adduct), and the compound represented by the following formula (3C) (di-adduct) were detected. Specifically, the peaks corresponding to each compound were identified as follows: m / z = 236.14: Compound represented by the following formula (1C) (Mw 235.33) m / z = 335.19: Compounds represented by the following formulas (2C) and (3C) (Mw 334.24)

[0065] １ H-NMR chemical shift: δ 7.35-7.14 ppm (m, -C ６ H ４ -), 3.86 ppm (d, J = 11Hz, -NH ２ -CH ２ -C ６ H ４ -), 3.80ppm (d, J=7.5Hz, -NH-CH ２ -C ６ H ４ -), 3.00-2.96 ppm (m, -NH-CH ２ -CH ２ -), 2.96-2.92ppm (m, -CH ２ -CH ２ -CO-), 2.92-2.88ppm (m, -N-CH ３ ), 2.57-2.50ppm (m, -N-CH ３ ), 1.67ppm (br, -CH ２ -NH-CH ２ -)

[0066] Furthermore, 0.1 g of the obtained reaction composition C was dissolved in 1 g of methanol, and the reaction composition was analyzed by GC analysis under the above conditions. The content of MXDA in reaction composition C was 20.2 mass %.

[0067] (Evaluation of Reaction Composition C, Preparation and Evaluation of Epoxy Resin Compositions) Evaluation of reaction composition C, and preparation and evaluation of epoxy resin compositions having the formulations shown in Table 1 were carried out in the same manner as in Example 1, except that reaction composition C was used instead of reaction composition A. The results are shown in Table 1. ​

[0068] Comparative Example 1 An epoxy resin composition having the composition shown in Table 1 was prepared and evaluated in the same manner as in Example 1, except that amine D (MXDA) was used instead of reaction composition A. The results are shown in Table 1. The viscosity and AHEW of MXDA are also shown in Table 1.

[0069] Comparative Example 2 An epoxy resin composition having the composition shown in Table 1 was prepared and evaluated in the same manner as in Example 1, except that amine E (G-328: a reaction product of metaxylylenediamine and epichlorohydrin, "Gaskamine 328" manufactured by Mitsubishi Gas Chemical Company, Inc.) was used instead of reaction composition A. The results are shown in Table 1. The viscosity and AHEW of G-328 are also shown in Table 1.

[0070] Comparative Example 3 (Production and Evaluation of Comparative Reaction Composition F Containing a Hydrogenated Product of the Reaction Product of MXDA and BAL) (Production of Comparative Reaction Composition F) [Step (1)] 40.0 g (0.3 mol) of metaxylylenediamine (MXDA, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was charged into a separable flask with an internal volume of 300 ml equipped with a stirrer, a thermometer, a nitrogen inlet tube, a dropping funnel, and a condenser, and 31.9 g (0.3 mol) of benzaldehyde (manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise over 15 to 20 minutes under stirring under a nitrogen stream. After completion of the dropwise addition, the temperature was raised to 80°C and the reaction was carried out for 30 minutes. １ H-NMR was measured to confirm that the aldehyde group of benzaldehyde １The reaction was terminated when the disappearance of the H peak was confirmed. Toluene was then added to the reaction product, and water in the system was removed by azeotropic dehydration to obtain an imine, a reaction product of meta-xylylenediamine and benzaldehyde in a molar ratio of 1 / 1. [Step (2)] 30.3 g of the imine obtained in step (1), 30 g of toluene, and 0.3 g of a 5% Pd / C catalyst (PE type, manufactured by N.E. Chemcat Corporation) were charged into an autoclave (volume 230 mL, material: SUS316L) equipped with a stirrer and a heater, and the gas phase was purged with hydrogen. The temperature was then raised with stirring, and the liquid temperature was raised to 80°C over 1 hour, after which the pressure was increased to 1 MPaG with hydrogen. The reaction was then continued for 1.5 hours under conditions of a liquid temperature of 80°C, with hydrogen being supplied as needed to maintain the pressure at 1 MPaG. The resulting reaction liquid was filtered to remove the hydrogenation catalyst, and then concentrated under vacuum to obtain 28.8 g of amino composition f, which is a reduction product of the imine obtained in step (1). The remaining metaxylylenediamine was removed from the obtained amino composition f by vacuum distillation to obtain 24.9 g of comparative reaction composition F. In comparative reaction composition F, the GC area ratios of the compound represented by the following formula (1F) (mono-adduct) and the compound represented by the following formula (2F) (di-adduct) were 74.7% and 25.3%, respectively.

[0071] The structural analysis of the compound represented by formula (1F) (mono-adduct) and the compound represented by formula (2F) (di-adduct) was carried out in the same manner as in Comparative Reaction Composition F. １ This was analyzed by H-NMR analysis. 1 H-NMR chemical shift: δ 7.1-7.9 ppm (m, -C ６ H ４ - and - C ６ H ５ ), δ3.8-3.85ppm (s, -CH ２ -C ６ H ４ -CH ２ - and -CH ２ -C ６ H ５ ), δ 1.9 ppm (s, -NH- and -NH ２ -)

[0072] (Evaluation of Comparative Reaction Composition F, Preparation and Evaluation of Epoxy Resin Compositions) Evaluation of Comparative Reaction Composition F, and preparation and evaluation of epoxy resin compositions having the formulations shown in Table 1 were carried out in the same manner as in Example 1, except that Comparative Reaction Composition F was used instead of Reaction Composition A in Example 1. The results are shown in Table 1.

[0073]

[0074] From Table 1, it can be seen that the cured product of the epoxy resin composition using the reaction composition of the present invention as an epoxy resin curing agent has excellent adhesion to aluminum substrates.

[0075] According to the present invention, it is possible to provide a reaction composition which, when used as an epoxy resin curing agent, gives a cured epoxy resin product having excellent adhesion to inorganic substances, particularly aluminum, as well as an epoxy resin curing agent and an epoxy resin composition containing the reaction composition, and a cured product thereof.

Claims

1. A reaction composition comprising a reaction product of xylylenediamine and a (meth)acrylamide derivative having only one (meth)acrylic group.

2. The reaction composition according to claim 1, wherein the reaction composition is obtained by reacting 0.8 to 1.8 moles of the (meth)acrylamide derivative with 1 mole of xylylenediamine.

3. The reaction composition according to claim 1, wherein the (meth)acrylamide derivative is at least one selected from the group consisting of N,N-dimethyl(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, and 4-(meth)acryloylmorpholine.

4. The reaction composition according to claim 1, wherein the reactant comprises at least one of the reactants represented by the following general formulas (1) to (3). 【Chemistry 1】 (wherein, R １ is a hydrogen atom or a methyl group. R ２ and R ３ are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms which may have a hydroxy group, or a group represented by -(CH ２ ) ｎ -NR ４ R ５ (n is a number from 1 to 10, and R ４ and R ５ are each independently a hydrogen atom or a methyl group). Alternatively, R ２ and R ３ are groups that form a ring structure with each other. However, R ２ and R ３ do not both become hydrogen atoms.)

5. An epoxy resin curing agent containing the reaction composition according to any one of claims 1 to 4.

6. An epoxy resin composition comprising an epoxy resin and the epoxy resin curing agent described in claim 5.

7. A cured product obtained by curing the epoxy resin composition described in claim 6.

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