JPH054409B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a curable epoxy resin composition. Furthermore, the present invention relates to a one-component heat-curable epoxy resin composition that has excellent storage stability and can be cured at relatively low temperatures and in a short time. Furthermore, the present invention relates to a curable epoxy resin composition that can provide a cured product having excellent mechanical strength and adhesive properties. [Prior Art] It is desired that a one-component latent curing epoxy resin composition be developed as a conventional structural adhesive, and a method using an imidazole compound or a salt obtained by reacting an imidazole compound with an acid as a curing agent is proposed. has been provided. However, such conventional one-component curable epoxy resin compositions still have insufficient latent properties, the curing reaction progresses gradually even at room temperature, storage stability is still unsatisfactory, and pot life is generally short. Ten
It only lasted about 1-20 days. Furthermore, conventional one-component curable epoxy resin compositions require high temperatures and long periods of time to cure; for example, a cured product with satisfactory physical properties cannot be obtained unless the composition is cured at 150 to 200°C for several hours. When cured at a low temperature and in a short time, the peel strength was particularly poor. Therefore, it has been desired to develop a new one-component curable epoxy resin composition that does not have such drawbacks. As an improvement plan for the above problems,
No. 155222, JP-A-57-100127, etc., adduct an epoxy resin to dialkylamine as a curing agent, and JP-A No. 59-53526 uses an adduct of an epoxy resin to amino alcohol or aminophenol. something is proposed. [Problems to be solved by the invention] However, when the above-mentioned curing agent is used, the compatibility, heat resistance, flexibility, and
Adhesion was not easy to control. An object of the present invention is to provide a one-component curable epoxy resin composition that has excellent storage stability and can be cured at relatively low temperatures and in a short time. A further object of the present invention is to provide a curable epoxy resin composition capable of providing a cured product having excellent mechanical strength, particularly excellent adhesiveness. A further object of the present invention is to provide a curable epoxy resin composition with excellent compatibility, heat resistance, flexibility, storage stability control, and the like. [Means for Solving the Problems] The curable epoxy resin composition of the present invention comprises, as essential components, () an epoxy resin having an average of more than one adjacent epoxy group in the molecule; ) general formula (In the formula, R ₁ and R ₂ are alkyl groups having 1 to 5 carbon atoms, and X is an alkylene group having 1 to 5 carbon atoms.) and an epoxy compound having an average of more than one adjacent epoxy group in the molecule. The epoxy group of the epoxy resin is 0.8-1 equivalent of the amino group of the amino compound.
A curing agent consisting of a reaction product obtained by reacting an epoxy-amine adduct obtained by reacting at a ratio of 2.5 equivalents with (b) one or more compounds selected from the group consisting of phenolic resins and polyvalent phenol compounds. , and is characterized by containing. Preferred epoxy resins () have the formula (Here, Z is a hydrogen atom, methyl group, or ethyl group)
Epoxy resin (-1) having an average of more than one substituted or unsubstituted glycidyl ether group in the molecule represented by the formula (Here, Z is a hydrogen atom, methyl group, or ethyl group)
An epoxy resin (-2) having an average of more than one substituted or unsubstituted glycidyl ether group in the molecule represented by the formula (Here, Z is a hydrogen atom, methyl group, or ethyl group)
Included are epoxy resins (-3) having more than one N-substituted or unsubstituted 1,2-epoxypropyl group in the molecule on average. Particularly preferred epoxy resins are those having an epoxy equivalent of 180 to 500. Epoxy resin (-
1) is an epoxy resin obtained by glycidyl etherification of a phenolic hydroxyl group and an epoxy resin obtained by glycidyl etherification of an alcoholic hydroxyl group, and preferred examples of such epoxy resin (-1) include: Polyglycidyl ether of polyvalent phenol having one or more aromatic nuclei (-1-1) and 1
Polyglycidyl ether of an alcoholic polyhydroxyl compound (
-1-2), etc. However, polyglycidyl ether (-1-
1) means, for example, that a polyhydric phenol (A) having at least one aromatic nucleus and an epihalohydrin (b) are mixed in a conventional manner in the presence of a reaction amount of a basic catalyst or basic compound such as sodium hydroxide. An epoxy resin containing polyglycidyl ether as a main reaction product, as obtained by reacting a polyhydric phenol (A) having at least one aromatic nucleus, and an epihalohydrin (b) in an amount of an acidic catalyst such as boron trifluoride. An epoxy resin such as that obtained by reacting a polyhalohydrin ether obtained by a conventional method with a basic compound such as sodium hydroxide in the presence of a polyvalent phenol having at least one aromatic nucleus ( An epoxy compound such as that obtained by reacting a polyhalohydrin ether obtained by reacting A) and epihalohydrin (b) in the presence of an amount of a basic catalyst such as triethylamine by a conventional method with a basic compound such as sodium hydroxide. It is resin. Similarly, polyglycidyl ether (-1-2) is a polyhydroxyl compound ( A polyhalohydrin ether obtained by reacting B) and epihalohydrin (b) in the presence of an amount of an acidic catalyst such as boron trifluoride in a conventional manner with a basic compound such as sodium hydroxide. It is an epoxy resin containing polyglycidyl ether as the main reaction product. Here, the polyvalent phenols (A) having at least one aromatic nucleus include mononuclear polyvalent phenols (A-1) having one aromatic nucleus and polyvalent phenols having two or more aromatic nuclei. There is polyhydric phenol (A-2). Examples of such mononuclear polyhydric phenols (A-1) include resorcinol, hydroquinone,
Pyrocatechol, phloroglucinol, 1,5
-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, and the like. In addition, as an example of polynuclear polyhydric phenol (A-2), the general formula (In the formula, Ar is an aromatic divalent hydrocarbon such as a naphthylene group and a phenylene group, and a phenylene group is preferable for the purposes of the present invention. Y′ and Y ₁ may be the same or different, and a methyl group, n -propyl group,
Alkyl groups, preferably with up to 4 carbon atoms, such as n-butyl, n-hexyl, n-octyl, or halogen atoms, i.e. chlorine, bromine, iodine or fluorine, or methoxy groups, Alkoxy groups are preferably alkoxy groups having up to 4 carbon atoms, such as methoxymethyl, ethoxy, ethoxyethyl, n-butoxy, amyloxy. When a substituent other than a hydroxyl group is present on either or both of the above-mentioned aromatic divalent hydrocarbon groups, these substituents may be the same or different. m and z are integers with values from 0 (zero) to the maximum value corresponding to the number of hydrogen atoms in the aromatic ring (Ar) that can be substituted with a substituent,
They can be the same or different values. R ₁ is for example

[Formula] -O-, -S-, -SO-, -SO ₂ -, or alkylene group such as methylene group, ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, 2-ethylhexamethylene group group, octamethylene group, nonamethylene group, decamethylene group or alkylidene group, such as ethylidene group, propylidene group, isopropylidene group, isobutylidene group, amylidene group, isoamylidene group, 1-phenylethylidene group or cycloaliphatic group such as 1,4 - cyclohexylene group, 1,3-cyclohexylene group, cyclohexylidene group or halogenated alkylene group or halogenated alkylidene group or halogenated cycloaliphatic group or alkoxy- and aryloxy-substituted Alkylidene groups or alkoxy- and aryloxy-substituted alkylene groups or alkoxy- and aryloxy-substituted cycloaliphatic groups such as methoxymethylene, ethoxymethylene, ethoxyethylene, 2-ethoxytrimethylene, 3- Ethoxypentamethylene group, 1,4-(2-methoxycyclohexane) group, phenoxyethylene group, 2
- phenoxytrimethylene group, 1,3-(2-phenoxycyclohexane) group or alkylene group such as phenylethylene group, 2-phenyltrimethylene group, 1,7-phenylpentamethylene group,
2-phenyldecamethylene group or aromatic group such as phenylene group, naphthylene group or halogenated aromatic group such as 1,4-(2-chlorophenylene) group, 1,4-(2-fluorophenylene) group or Alkoxy and aryloxy substituted aromatic groups such as 1,4-(2-methoxyphenylene) group, 1,4-(2-ethoxyphenylene) group,
1,4-(2-n-propoxyphenylene) group,
1,4-(2-phenoxyphenylene) group or an alkyl-substituted aromatic group such as 1,4-(2-phenoxyphenylene) group
-methylphenylene) group, 1,4-(2-ethylphenylene) group, 1,4-(2-n-propylphenylene) 1,4-(2-n-butylphenylene) group
1,4-(2-n-dodecylphenylene) group, or R 1 is a divalent group such as a divalent hydrocarbon group such as a 1,4-(2-n-dodecylphenylene) group, or R ₁ is e.g. It can also be a ring fused to one of the Ar groups, as in the case of the compound represented by R ₁
can also be a polyalkoxy group, such as a polyethoxy group, a polypropoxy group, a polythioethoxy group, a polybutoxy group, a polyphenylethoxy group, or R ₁ can be, for example, a polydimethylsiloxy group,
It can be a group containing a silicon atom, such as a polydiphenylsiloxy group, a polymethylphenylsiloxy group, or R ₁ can be an aromatic ring, a tertiary-amino group, an ether bond, a carbonyl group, or a sulfur or sulfoxide group. 2 separated by a sulfur-containing bond
There are polynuclear dihydric phenols, which can be one or more alkylene or alkylidene groups. Particularly preferred among such polynuclear divalent phenols is the general formula (In the formula, Y′ and Y ₁ have the same meanings as above, m
and z are values from 0 to 4, and R ₁ is preferably 1
alkylene or alkylidene group or formula with ~3 carbon atoms

【formula】

[Formula] or It is a polynuclear divalent phenol represented by ). Examples of such dihydric phenols include 2,2-bis(p-
hydroxyphenyl)-propane, 2,4'-dihydroxydiphenylmethane, bis-(2-hydroxyphenyl)-methane, bis-(4-hydroxyphenyl-methane, bis-(4-hydroxy-2,
6-dimethyl-3-methoxyphenyl)-methane,
1,1-bis-(4-hydroxyphenyl)-ethane, 1,2-bis-(4-hydroxyphenyl)-
Ethane, 1,1-bis-(4-hydroxy-2-
Chlorphenyl)-ethane, 1,1-bis-(3,
5-dimethyl-4-hydroxyphenyl)-ethane, 1,3-bis-(3-methyl-4-hydroxyphenyl)-propane, 2,2-bis(3,5
-dichloro-4-hydroxyphenylpropane,
2,2-bis(3-phenyl-4-hydroxyphenyl)-propane, 2,2-bis-(3-isopropyl-4-hydroxyphenyl)-propane,
2,2-bis-(2-isopropyl-4-hydroxyphenyl)-propane, 2,2-bis-(4-
hydroxynaphthyl)-propane, 2,2-bis-(4-hydroxyphenyl)-pentane, 3,3
-bis-(4-hydroxyphenyl)-pentane,
2,2-bis-(4-hydroxy-phenyl)-heptane, bis-(4-hydroxyphenylmethane,
Bis-(4-hydroxyphenyl)-cyclohexylmethane, 1,2-bis(4-hydroxyphenyl)-1,2-bis-(phenyl)-propane, 2,
Bis-(hydroxyphenyl) such as 2-bis-(4-hydroxyphenyl)-1-phenylpropane
Alkanes or dihydroxybiphenyl such as 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl 2,4'-dihydroxybiphenyl or bis-(4-hydroxyphenyl)-sulfone, 2,4' -dihydroxydiphenylsulfone, chlor-2,4-dihydroxydiphenylsulfone, 5-chloro-4,4'-dihydroxydiphenylsulfone, 3'-chloro-4,4'-dihydroxydiphenylsulfone. (Hydroxyphenyl)-sulfone or bis-(4-hydroxyphenyl)-ether, 4,3'-(or 4,2'-
or 2,2'-dihydroxy-diphenyl) ether, 4,4'-dihydroxy-2,6-dimethyldiphenyl ether, bis-(4-hydroxy-3
-isobutylphenyl)-ether, bis-(4-
hydroxy-3-isopropylphenyl)-ether, bis-(4-hydroxy-3-chlorophenyl)-ether, bis-(4-hydroxy-3-
fluorophenyl)-ether, bis-(4-hydroxy-3-bromphenyl)-ether, bis-(4-hydroxynaphthyl)-ether, bis-
(4-hydroxy-3-chlornaphthyl)-ether, bis-(2-hydroxybiphenyl)-ether, 4-4'-dihydroxy-2,6-dimethoxy-diphenyl ether, 4,4'-dihydroxy-
Includes di-(hydroxyphenyl)-ethers such as 2,5-diethoxydiphenyl ether, and also 1,1-bis-(4-hydroxyphenyl)-2
-phenyl)-2-phenylethane, 1,3,3
-trimethyl-1-(4-hydroxyphenyl)-
6-hydroxyindan, 2,4-bis-(p-
Hydroxyphenyl)-4-methylpentane is also suitable. Furthermore, another preferred group of such polynuclear divalent phenols has the general formula (wherein R ₃ is a methyl or ethyl group, R ₂ is an alkylidene group having 1 to 9 carbon atoms or other alkylene group, and p is 0 to 4), for example, 1,4-bis-( 4-
hydroxybenzyl)-benzene, 1,4-bis-(4-hydroxybenzyl)-tetramethylbenzene, 1,4-bis-(4-hydroxybenzyl)
-tetraethylbenzene, 1,4-bis-(p-
Examples thereof include hydroxychloromyl)-benzene, 1,3-bis(p-hydroxychlormyl)-benzene, and the like. Other polynuclear polyhydric phenols (A-2) include, for example, initial condensates of phenols and carbonyl compounds (e.g., initial condensates of phenolic resins, condensation reaction products of phenols and acrolein, phenol and glyoxal condensation reaction product, phenol and pentanediallyl condensation reaction product, resorcinol and acetone condensation reaction product, xylene-phenol-formalin initial condensate), condensation product of phenols and polychloromethylated aromatic compounds (Example: condensation product of phenol and bischloromethylxylene), etc. Therefore, the polyhydroxyl compound (B) is a catalyst that promotes the reaction between the above-mentioned polyhydric phenol (A) having at least one aromatic nucleus and an alkylene oxide with an OH group and an epoxy group. -ROH (here, R is an alkylene group derived from alkylene oxide) or (and) -(RO) _o H which is bonded to the phenol residue through an ether bond obtained by reaction in the presence of (Here, R is an alkylene group derived from alkylene oxide, and one polyoxyalkylene chain may contain different alkylene groups. n is an integer of 2 or more indicating the number of polymerized oxyalkylene groups) It is a compound that has a group. In this case, the polyhydric phenol (A)
The ratio of alkylene oxide to the OH group of the polyhydric phenol (A) is preferably 1:10 or more, preferably 1:1 to 3. (equivalent: equivalent). Examples of alkylene oxides include ethylene oxide, propylene oxide, butylene oxide, etc., but those that generate side chains when reacting with the polyhydric phenol (A) to form an ether bond are particularly preferred; Examples include propylene oxide, 1,2-butylene oxide, and 2,3-butylene oxide, with propylene oxide being particularly preferred. A particularly preferred group of such polyhydroxyl compounds has the general formula (In the formula, Y′, Y′ ₁ , m, z and R ₁ are the above (1-
1) where R is an alkylene group having 2 to 4 carbon atoms and n ₁ and n ₂ have values of 1 to 3. Yet another preferred group of such polyhydroxyl compounds has the general formula (In the formula, R ₁ , R ₂ , and R ₃ are the same as those in formula (1-2) above, R is an alkylene group having 2 to 4 carbon atoms, and n ₁ and n ₂ have values of 1 to 3. ) It is a polyhydroxyl compound represented by Also, epihalohydrin (b) has the general formula (Here, Z is a hydrogen atom, a methyl group, an ethyl group,
X' is a halogen atom), and examples of such epihalohydrin (b) include epichlorohydrin, epibromohydrin, 1,2-epoxy-2-methyl-3-chloropropane, ,2-epoxy-2
-Ethyl-3-chloropropane and the like. Examples of acidic catalysts that promote the reaction between the epihalohydrin (b) and the polyhydric phenol (A) or polyhydroxyl compound (B) include boron trifluoride, tin chloride,
Lewis acids such as zinc chloride and ferric chloride, derivatives exhibiting these activities (eg, boron trifluoride-ether complex compounds), or mixtures thereof can be used. Similarly, epihalohydrin (b) and polyhydric phenol (A)
Basic catalysts that promote the reaction with include alkali metal hydroxides (e.g. sodium hydroxide), alkali metal alcoholates (e.g. sodium ethylate), and tertiary amine compounds (e.g. triethylamine, triethanolamine). , a quaternary ammonium compound (e.g., tetramethylammonium bromide), or a mixture thereof, such that a glycidyl ether is formed simultaneously with such a reaction, or a halohydrin formed as a result of the reaction. As the basic compound that closes the ether by dehydrohalogenation reaction to generate glycidyl ether, alkali metal hydroxides (e.g., sodium hydroxide), alkali metal salts of aluminates (e.g., sodium aluminate), etc. are convenient. Often used. Of course, these catalysts and basic compounds can be used as they are or as solutions in appropriate inorganic and/or organic solvents. Epoxy resins (1-2) having an average of more than one substituted or unsubstituted glycidyl ester group in the molecule include polyglycidyl esters of aliphatic polycarboxylic acids or aromatic polycarboxylic acids, such as Also included are epoxy resins obtained by polymerizing glycidyl methacrylate synthesized from epihalohydrin (b) represented by the general formula (2) and methacrylic acid. Examples of epoxy resins (1-3) having more than one N-substituted or unsubstituted 1,2-epoxypropyl group in the molecule include aromatic amines (e.g. aniline or alkyl substituents in the nucleus). epoxy resin obtained from the epihalohydrin (b) represented by the above general formula (2), the initial condensate of aromatic amine and aldehyde (for example, aniline-formaldehyde initial condensate, aniline-phenol-formaldehyde initial condensate, Examples include epoxy resins obtained from a condensate) and epihalohydrin (b). In addition, conventionally known epoxy resins such as the various epoxy resins described in "Manufacture and Application of Epoxy Resins" (edited by Hiroshi Kakiuchi) may be used. General formula used in the present invention (In the formula, R ₁ and R ₂ are alkyl groups having 1 to 5 carbon atoms,
Examples of amino compounds () (a) represented by X is an alkylene group having 1 to 5 carbon atoms include dimethylaminopropylamine (DMAPA), diethylaminopropylamine (DEAPA), dipropylaminopropylamine (DPAPA), dibutylamino Examples include propylamine (DBAPA), dimethylaminoethylamine (DMAEA), diethylaminoethylamine (DEAEA), dipropylaminoethylamine (DPAEA), dibutylaminoethylamine (DBAEA), and the like. Among these, DMAPA, DEAPA, etc. are preferred. As the epoxy resin () (a) used in the present invention, the above-mentioned epoxy resin () is used,
Alternatively, monoepoxy compounds such as butylglycidyl ether, phenylglycidyl ether, monoglycidyl ether of P-tert-butylphenol, monoglycidyl ether of Sec-butylphenol, glycidyl methacrylate, Karzilla E ( Monoesters such as those manufactured by Yuka Shell Co., Ltd. (trade name) can also be used in combination. The epoxy-amine adduct ()(a) of the present invention is
The epoxy group of the epoxy resin (a) per equivalent of active amino group NH ₂ of the amino compound (a),

〔Effect of the invention〕

The effect of the present invention is to provide a one-component curable epoxy resin composition that has excellent storage stability and can be cured at relatively low temperatures and in a short time. A further advantage of the present invention is that it provides a curable epoxy resin composition that can provide a cured product having excellent mechanical strength and adhesive properties. A further advantage of the present invention is that it provides a curable epoxy resin composition with excellent control over compatibility, heat resistance, flexibility, storage stability, and the like. [Example] The present invention will be explained in more detail below with reference to Examples. Example 1 Diethylaminopropylamine (DEAPA)
In 130gr, add Adeka Resin EP-4100 (epoxy resin obtained from bisphenol A and epihalohydrin, epoxy equivalent 190, viscosity 100 poise (25
℃))) was added little by little, and while suppressing heat generation, the amino group/epoxy group addition reaction was carried out for 100×3 hours + 120℃×1 hour to obtain the reaction product (A). Phenol 650g, formalin (30%) 585g
3.3g of oxalic acid and 23g of hydrochloric acid (15%) by a known method for producing phenolic resin to a softening point of approximately 100.
Obtain a phenolic novolak resin () at ℃. Furthermore, phenol novolac resin () was added to the above reaction product (A) at the following blending ratio, and the mixture was heated to 150°C.
A melt masking reaction was performed for 2 hours to obtain the following latent epoxy curing agent.

[Table] Xylene resin manufactured by Su Kagaku)

After finely pulverizing the above latent curing agent, it is blended with an epoxy resin in the following proportions, and after mixing, a one-component curable epoxy composition is obtained. Table 1 shows the measurement results for the gel time, storage stability, and tensile shear strength of the cured product of this composition.

【table】

[Table] Example 2 Adding Adekal Resin EP-4100 to DEAPA132gr
After adding 252 gr, 16 gr of PGE (phenyl glycidyl ether), 70 gr of toluene, and 70 gr of IPA and carrying out an addition reaction for 4 hours while refluxing the solvent system at 80 to 90°C, toluene and IPA were distilled off. After the solvent is completely distilled off, a reaction product (B) is obtained. The above reaction product and the phenol novolac resin () or bisphenol F of Example 1 were blended in the following proportions and subjected to a melt mask reaction at 150°C for 3 hours.

[Table] After finely pulverizing the above latent curing agent, it was blended with an epoxy resin (EP-4100) in the following formulation, and after mixing, a one-component curable epoxy resin composition was obtained. Table 2 shows the gel time, storage stability, and tensile shear strength of the cured product of this composition.

[Table] Example 3 DEAPA130gr, Adekal Resin EP-5100-75
× (Epoxy resin obtained from bisphenol A and epichlorohydrin, solid content 75%, epoxy equivalent (solid content equivalent) 470) 640gr, PGE99gr,
After adding 45 gr of IPA and reacting for 3 hours at 80 to 85°C under solvent reflux, the solvent was distilled off to obtain a reaction product (C). The above reaction product (B) and the phenol novolac resin () of Example 1 were blended in the following proportions and heated to 150°C.
Perform a time-melting mask reaction.

[Table] After finely pulverizing the above latent curing agent, it was blended with an epoxy resin in the proportions shown below, and after mixing, a one-component curable epoxy composition was obtained. Table 3 shows the measurement results for the gel time, storage stability, and tensile shear strength of the cured product of this composition.

[Table] Example 4 Dimethylaminopropylamine 30gr, Adekalezin EP-4100 61gr, toluene 10gr,
Add 10 gr of IPA and react at 85°C under solvent reflux for 3 hours. The solvent is removed to obtain the reaction product (D). The above reaction product (D) and the phenol novolak resin () of Example 1 were blended in the following proportions and heated at 150°×
The melt heating reaction is carried out for 3 hours.

[Table] After finely pulverizing the above latent curing agent, it was blended with an epoxy resin in the proportions shown below, and after mixing, a one-component curable epoxy composition was obtained. Table 4 shows the measurement results for the gel time, storage stability, and tensile shear strength of the cured product of this composition.

【table】

【table】

Claims (1)

[Claims] 1. As essential constituents, () an epoxy resin having an average of more than one adjacent epoxy group in the molecule; ()(a) a general formula (In the formula, R ₁ and R ₂ are alkyl groups having 1 to 5 carbon atoms, and X is an alkylene group having 1 to 5 carbon atoms.) and an epoxy compound having an average of more than one adjacent epoxy group in the molecule. The epoxy group of the epoxy resin is 0.8-1 equivalent of the amino group of the amino compound.
(b) A cured product consisting of a reaction product obtained by reacting one or more compounds selected from the group consisting of a phenolic resin and a polyvalent phenol compound to an epoxy-amine adduct obtained by reacting at a ratio of 2.5 equivalents. A curable epoxy resin composition comprising: an agent; and a curable epoxy resin composition.