JPH11310689A - Epoxy resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a one-pack type composition capable of manifesting excellent preservation stability and low-temperature curability without being influenced by a resin, a diluent, an additive or a mixing method used and useful as an adhesive, a coating material, etc., by using a zeolite and a specific alkoxide compound in combination. SOLUTION: This composition contains (A) an epoxy resin having two or more epoxy groups in the molecule, (B) a solid dispersed type amine adduct- based latent curing agent (e.g. a product obtained by reacting an amine compound with an epoxy compound, an isocyanate compound or a urea compound), (C) an alkoxide compound of titanium, zirconium or boron e.g. a compound represented by the formula M<1> (OR)n R4-n [M<1> is Ti or Zr; R is an alkyl; (n) is 1-4]} and (D) a zeolite (e.g. the one having <=100 μm average particle diameter). The composition preferably contains the components C and D in respective amounts of 0.1-20 pts.wt. and 1-100 pts.wt. based on the component A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a novel epoxy resin composition. More specifically, the present invention relates to an epoxy resin composition which is excellent in storage stability, is quickly cured by heating, and gives a cured product having excellent performance.

[0002]

2. Description of the Related Art Epoxy resins have been used in various fields such as electric insulating materials, adhesives, various molded products and paints due to their excellent electrical, mechanical and chemical properties. As the form of the epoxy resin composition, the main component component and the hardener component were separately manufactured and manufactured, and a two-pack type used by mixing immediately before the operation and the main component component and the hardener component were mixed into one component from the beginning. There is a one-pack type, but in the case of a two-pack type, not only is there always anxiety about the accuracy of the mixing ratio and the uniformity of the mixing, but also the viscosity of the mixed composition increases with time immediately after mixing, There is a problem that handling by an automatic device is difficult. The one-pack type epoxy resin composition has solved such a problem.

[0003] As a method for obtaining a one-pack type epoxy resin composition, a low-temperature storage method in which a relatively low-reactivity composition is stored at a low temperature, a curing agent is encapsulated in microcapsules and released by heating or pressurizing. Microencapsulation method, moisture curing method using a compound that reacts with moisture such as ketoimine to release amine as a curing agent, or latent curing agent method using a heat-reactive curing agent that activates at a predetermined temperature or higher. Although various proposals have been made, the latent curing agent method is effective as a method for obtaining a composition which cures in a short time and has good storage stability. As a curing agent used in the latent curing agent method,
Dicyandiamide, dibasic dihydrazide, boron trifluoride-amine adduct, guanamines, and melamine, etc., are cured at a lower temperature, and cured to obtain an epoxy resin composition having good storage stability. As the agent, a solid dispersion type amine adduct latent curing agent has been proposed. However, while having both low-temperature curability and storage stability, the epoxy resin used, or
Diluents, selection of additives such as fillers, or the adoption of a mixing method that is advantageous for homogenization of three rolls and the like, has the disadvantage that storage stability is significantly impaired, and is not always satisfactory. Was.

In order to remedy this drawback, a composition in which the surface of a solid dispersion type latent curing agent is treated with an aluminum alcoholate or an aluminum chelate compound or a composition disclosed in
223027), a composition in which the surface of a solid dispersion type amine adduct-based latent curing agent is coated with a borate compound (JP-A-6-73156), and a metal dispersed in an epoxy resin to which a solid dispersion type amine adduct-based latent curing agent is added. (Japanese Unexamined Patent Application Publication No. 7-196)
776), or a composition in which zeolite is added to an epoxy resin to which a solid dispersion type amine adduct-based latent curing agent is added (Japanese Patent Application Laid-Open No. 6-200227). It hadn't been possible.

[0005] As described above, excellent storage stability and low temperature can be obtained without being influenced by the epoxy resin used, the additive such as a diluent, a filler, or the mixing method of three rolls. There has been a great demand for a one-pack type epoxy resin composition which has curability and is excellent in the performance of a cured product after curing.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide an excellent resin composition which is not affected by the epoxy resin used, the additive such as a diluent or a filler, or the method of mixing three rolls. An object of the present invention is to provide a one-pack type epoxy resin composition having storage stability and low-temperature curability.

[0007]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the combined use of zeolite and a specific alkoxide compound in an epoxy resin composition is extremely effective in solving the above problems. This led to the completion of the present invention.

That is, the present invention provides (1) an epoxy resin having two or more epoxy groups in one molecule, (2) a solid dispersion type amine adduct latent curing agent, (3) an alkoxide of titanium, zirconium or boron. Compound and (4)
An epoxy resin composition comprising zeolite.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The epoxy resin in the present invention comprises:
It has two or more epoxy groups per molecule,
The number of epoxy groups per molecule is an average value. Preferred epoxy resins include the following. That is, polyglycidyl ether obtained by reacting a polyhydric phenol such as bisphenol A, bisphenol F, bisphenol AD, catechol, resorcinol, or a polyhydric alcohol such as glycerin or polyethylene glycol with epichlorohydrin; p-hydroxybenzoic acid; β-
Glycidyl ether esters obtained by reacting a hydroxycarboxylic acid such as hydroxynaphthoic acid with epichlorohydrin; polyglycidyl esters obtained by reacting a polycarboxylic acid such as phthalic acid and terephthalic acid with epichlorohydrin; Phenol novolak resin, epoxidized cresol novolak resin, epoxidized polyolefin, cycloaliphatic epoxy resin and the like.

The solid dispersion type amine adduct latent curing agent in the present invention is a solid which is insoluble in an epoxy resin at room temperature, solubilized by heating, and functions as a curing agent. Preferred solid dispersion type amine adduct-based latent curing agents include reaction products of amine compounds and epoxy compounds (amine-epoxy adducts) and reaction products of amine compounds and isocyanate compounds or urea compounds (urea-type adduct systems). And the surface of these curing agents are treated with an isocyanate compound or an acidic compound.

The epoxy compound used as a raw material for producing the latent curing agent in the present invention is, for example, a polyhydric phenol such as bisphenol A, bisphenol F, catechol, resorcinol or a polyhydric alcohol such as glycerin or polyethylene glycol and epichlorohydrin. A polyglycidyl ether obtained by reacting
Glycidyl ether ester obtained by reacting a hydroxycarboxylic acid such as p-hydroxybenzoic acid or β-hydroxynaphthoic acid with epichlorohydrin; obtained by reacting a polycarboxylic acid such as phthalic acid or terephthalic acid with epichlorohydrin Polyglycidyl esters; glycidylamine compounds obtained from 4,4'-diaminodiphenylmethane, m-aminophenol, and the like; further, polyfunctional epoxy compounds such as epoxidized phenol novolak resins, epoxidized cresol novolak resins, and epoxidized polyolefins; And monofunctional epoxy compounds such as butyl glycidyl ether and glycidyl methacrylate.

The amine compound used as a raw material for producing a latent curing agent in the present invention has at least one active hydrogen in one molecule capable of undergoing an addition reaction with an epoxy group or an isocyanate group, and has a primary amino group and a secondary amino group. It may be any as long as it has at least one substituent selected from an amino group and a tertiary amino group in one molecule. Preferred examples of such an amine compound are shown below.

For example, diethylenetriamine, triethylenetetramine, n-propylamine, 2-hydroxyethylaminopropylamine, cyclohexylamine,
Amine compounds such as dimethylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, and N-methylpiperazine; and imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, and 2-phenylimidazole. Primary or secondary amines having a tertiary amino group in one molecule such as compounds, 2-dimethylaminoethanol, 1-methyl-2-dimethylaminoethanol, 1-phenoxymethyl-2-dimethylamino Ethanol, 2-diethylaminoethanol, 1-butoxymethyl-2-dimethylaminoethanol, 1- (2-hydroxy-3-phenoxypropyl) -2-methylimidazole, 1- (2-hydroxy-3-phenoxypropyl) -2 -Ethyl 4-methylimidazole, 1- (2
-Hydroxy-3-butoxypropyl) -2-methylimidazole, 1- (2-hydroxy-3-butoxypropyl) -2-ethyl-4-methylimidazole, 1-
(2-hydroxy-3-phenoxypropyl) -2-phenylimidazoline, 1- (2-hydroxy-3-butoxypropyl) -2-phenylimidazoline, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (Dimethylaminomethyl) phenol, N-β-hydroxyethylmorpholine, 2-dimethylaminoethanethiol, 2-mercaptopyridine, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 4-
Mercaptopyridine, N, N-dimethylaminobenzoic acid, N, N-dimethylglycine, nicotinic acid, isonicotinic acid, picolinic acid, N, N-dimethylglycine hydrazide, N, N-dimethylpropionic hydrazide,
There are alcohols, phenols, thiols, carboxylic acids, and hydrazides having a tertiary amino group in one molecule, such as nicotinic acid hydrazide, isonicotinic acid hydrazide and the like.

Further, when the above-mentioned epoxy compound and the amine compound are subjected to an addition reaction to produce the latent curing agent of the present invention, active hydrogen is used as a third component in one molecule.
Active hydrogen compounds having at least one active hydrogen compound can also be added.
Preferred examples of such active hydrogen compounds include, for example, bisphenol A, bisphenol F, bisphenol S, hydroquinone, catechol, resorcinol,
Polyhydric phenols such as pyrogallol and phenol novolak resins; polyhydric alcohols such as trimethylolpropane; triethylenetetramine, cyclohexylamine;
Amines such as piperazine and aniline; polycarboxylic acids such as adipic acid and phthalic acid; 1,2-dimercaptoethane, 2-mercaptoethanol, 1-mercapto-3
-Phenoxy-2-propanol, mercaptoacetic acid, anthranilic acid, lactic acid and the like.

The isocyanate compound used in the production of the latent curing agent in the present invention includes, for example, n
Monofunctional isocyanate compounds such as butyl isocyanate, isopropyl isocyanate, phenyl isocyanate, benzyl isocyanate, etc .; hexamethylene diisocyanate, toluylene diisocyanate,
Polyfunctional isocyanates such as 1,5-naphthalene diisocyanate, diphenylmethane-4, -4'-diisocyanate, isophorone diisocyanate, xylylene diisocyanate, p-phenylene diisocyanate 1,3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate, etc. Compounds: Further, compounds containing a terminal isocyanate group obtained by reacting these polyfunctional isocyanate compounds with an active hydrogen compound can also be used. Examples of such compounds include toluylene diisocyanate and trimethylolpropane Reaction product having a terminal isocyanate group obtained by the reaction with toluylene diisocyanate and pentaerythritol There are things.

The latent curing agent in the present invention comprises the above-mentioned two components (a) epoxy compound or isocyanate compound and (b) amine compound, or (a) epoxy compound or isocyanate compound, (b) amine compound and (c) ) The three components of the active hydrogen compound are mixed and reacted at a temperature of from room temperature to 20 ° C, and then solidified and pulverized, or reacted in a solvent such as methyl ethyl ketone, dioxane, tetrahydrofuran and the like. Can be easily obtained by grinding.

Commercially available solid dispersion type amine adduct latent curing agents in the present invention include the following.

For example, as the amine-epoxy adduct system, "Amicure PN-23", "Amicure P"
N-H "," Amicure MY-24 "(above, trade name of Ajinomoto Co., Inc.)," Hardner H-3615S ",
"Hardner H-3293S" (the above are the brand names of AS R Co., Ltd.), "NOVACURE HX-372"
1 "," NOVACURE HX-3742 "(trade name of Asahi Kasei Corporation)," Ancamine 2014A "
S "," Ancamine 2014FG "(trade name of Pacific Anchor Chemical) and the like. As a urea-type adduct, “Fujicure FXE-
1000 "and" Fujicure FXR-1030 "(trade names of Fuji Kasei Co., Ltd.).

The zeolite in the present invention is a hydrated metal salt composed of alumina and silicate, and may be either a natural product or a synthetic product, but preferably has a capability of adsorbing water and a polar solvent. In order to express this adsorption ability more effectively, it is preferable to uniformly disperse the resin in the resin of the present invention, and the average particle diameter of the zeolite is preferably 100 μm or less, more preferably 40 μm or less.
When the average particle diameter is too small, the effect of increasing the viscosity of the epoxy resin composition increases, and when an amount that exerts the effects of the present invention is added, the viscosity increase is large, and the workability deteriorates. It is preferably at least 0.01 μm. Preferred zeolites having the above properties include, for example, "Molecular sieve 3A", "Molecular sieve 4A", "Molecular sieve 5A", "Molecular sieve 13X" (all trade names of Union Showa Co., Ltd.), "Zeolam 3A" and "Zeoram 4
A "(Toshiso Corporation). The preferred amount of zeolite is 1 to 100 parts by weight, more preferably 1 to 60 parts by weight, per 100 parts by weight of the epoxy resin. If the amount of the zeolite is too small, the storage stability of the composition of the present invention is reduced. Conversely, if the amount is too large, the viscosity of the epoxy resin composition is increased and the workability may be deteriorated.

The metal alkoxide compound in the present invention is an alkoxide compound of titanium, zirconium or boron, and is preferably represented by the following general formula (1) or (2).

[0021]

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[0022]

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As the alkyl group (R), any one having at least one carbon atom can be used.
Are preferred. The types of alkyl groups in one compound may be the same or different, and may be saturated or unsaturated. Furthermore, there is no problem even if two or more alkyl groups in the compound are bonded to have a cyclic structure, or two or more condensates of these compounds arbitrarily selected. In the composition of the present invention, two or more alkoxides of titanium, zirconium or boron can be used in combination with the alkoxide compound represented by the above (1) or (2).

Preferred examples of the titanium alkoxide compound in the present invention include tetraalkyl titanates, such as tetramethyl titanate, tetraethyl titanate, tetra-n-propyl titanate, tetraisopropyl titanate (TPT), and tetra-n- Butyl titanate (TBT), tetraisobutyl titanate, tetra-tert-butyl titanate, tetra-n
-Pentyl titanate, tetra-n-hexyl titanate, tetraisooctyl titanate (TOT), tetra-n-lauryl titanate and oligomers thereof. Among them, those having an alkyl group having 3 to 4 carbon atoms, such as tetraisopropyl titanate (TPT) and tetra-n-butyl titanate (TB)
T) and the like are preferable.

Preferable examples of the alkoxide compound of zirconium in the present invention include tetraalkyl zirconate, for example, tetraethyl zirconate,
Tetra-n-propyl zirconate, tetraisopropyl zirconate (TPZ), tetra-n-butyl zirconate, tetra-sec-butyl zirconate, tetra-tert-butyl zirconate, tetra-n-pentyl zirconate, tetra- Examples include tert-pentyl zirconate, tetra-tert-hexyl zirconate, tetra-n-heptyl zirconate, tetra-n-octyl zirconate, tetra-n-stearyl zirconate and oligomers thereof. Among them, those having an alkyl group having 3 to 4 carbon atoms, for example,
Tetraisopropyl zirconate (TPZ), tetra-
n-Butyl zirconate is preferred.

Preferred examples of the boron alkoxide compound in the present invention include trialkyl borates, such as trimethyl borate, triethyl borate, tri-n-propyl borate, triisopropyl borate, tri-n-butyl borate, and the like. Examples include tricresyl borate, tri-tert-butyl borate, trihexadecyl borate, tricetyl borate, tristearyl borate, triphenyl borate, tolyl borate, tribenzyl borate and oligomers thereof. Among them, those having an alkyl group having 3 to 4 carbon atoms, such as triisopropyl borate (TPB) and tri-n-butyl borate (TBB), are particularly preferable.

When the addition amount of these alkoxide compounds is too small, the storage stability is reduced. When the addition amount is too large, the curing speed of the epoxy resin is lowered or, on the contrary, the storage stability is deteriorated. It is in the range of 0.1 to 20 parts by weight, preferably 0.1 to 15 parts by weight, per 100 parts by weight.

The epoxy resin composition of the present invention may contain various additives such as a filler, a diluent, a solvent, a pigment, a flexibility-imparting agent, a coupling agent and an antioxidant, if necessary. it can.

Further, the cured product of the composition of the present invention exhibits no problem in characteristics even if it contains zeolite or a specific alkoxide compound, exhibits the original excellent performance of epoxy resin, and can be used for adhesives, paints, It can be utilized by utilizing its features in a wide range of fields such as electric insulating materials and laminated structures.

[0030]

The present invention will be described more specifically below with reference to examples. In the following examples, the storage stability is measured by measuring the number of days until the initial viscosity exceeds twice the initial viscosity in a thermostatic chamber stored at a predetermined temperature (40 ° C.), and the curability is evaluated by the gel time at 120 ° C. or 150 ° C. Was evaluated by measuring.
The viscosity was measured according to JISK6833. In the following examples and comparative examples, “parts” indicates “parts by weight”.

Example 1 Bisphenol A type epoxy resin "Epicoat 828"
(Product name of Yuka Shell Epoxy Co., Ltd.)
"Amicure PN-23" (trade name of Ajinomoto Co., Inc.)
20 copies and 1 copy of "Aerosil # 200" (trade name of Nippon Aerosil Co., Ltd.), 10 copies of "Molecular Sieve 3A" (trade name of Union Showa Co., Ltd.),
One part of tetraisopropyl titanate (TPT) was added and mixed as an alkoxide compound, and the composition was further uniformly dispersed using a three-roll mill to obtain an epoxy resin composition. The results of measuring the gel time and storage stability of this composition are shown in Table 1 below.

Example 2 The composition of Example 1 was added to the composition of Example 1 as "YED-1" as a reactive diluent.
22 "(trade name of Yuka Shell Epoxy Co., Ltd.) was added and mixed, and this composition was more uniformly dispersed using a three-roll mill to obtain an epoxy resin composition. The results of measuring the gel time and storage stability of this composition are shown in Table 1 below.

Example 3 To the composition of Example 2, 20 parts of talc as a filler was added and mixed, and this composition was more uniformly dispersed using a three-roll mill to obtain an epoxy resin composition. Table 1 shows the results of measuring the gel time and storage stability of these compositions.

Examples 4 to 7 The alkoxide compound of the composition of Example 3 was replaced with tetra-n-
Butyl titanate (TBT), tetraisooctyl titanate (TOT), tetraisopropyl zirconate (TPZ), and tetra-n-butyl borate (TBB) are mixed and replaced, and the composition is more uniformly formed using a three-roll mill. It was dispersed to obtain an epoxy resin composition. The results of measuring the gel time and storage stability of these compositions are shown in Table 1 below.

Comparative Examples 1 to 7 The respective compositions of Examples 1 to 7 were mixed without adding “Molecular Sieve 3A” (trade name of Union Showa Co., Ltd.). The epoxy resin composition was more uniformly dispersed. The results of measuring the gel time and storage stability of this composition are shown in Table 1 below.
Shown in

Comparative Examples 8 to 10 The respective compositions of Examples 1 to 3 were mixed without adding an alkoxide compound, and the compositions were mixed using a three-roll mill.
The epoxy resin composition was more uniformly dispersed. The results of measuring the gel time and storage stability of this composition are shown in Table 1 below.

[0037]

[Table 1]

Epicoat 807: bisphenol A type epoxy resin (manufactured by Yuka Shell Epoxy Co., Ltd.) YED-122: butylphenyl glycidyl ether (manufactured by Yuka Shell Epoxy Co., Ltd.) Amicure PN-23: solid dispersion type amine adduct type latent Curing agent (manufactured by Ajinomoto Co.) Aerosil # 200: finely divided silica (manufactured by Nippon Aerosil Co., Ltd.) Molecular sieve 3A: synthetic zeolite (manufactured by Union Showa Co., Ltd.) TPT: tetraisopropyl titanate (manufactured by Mitsubishi Gas Chemical Co., Ltd.) TBT: tetra -N-butyl titanate (manufactured by Mitsubishi Gas Chemical Co., Ltd.) TOT: tetraisooctyl titanate (manufactured by Mitsubishi Gas Chemical Co., Ltd.) TPZ: tetraisopropyl zirconate (reagent) TBB: tri-n-butyl borate (reagent)

As can be seen from Table 1 above, in Comparative Examples 1 to 10 in which either the metal alkoxide or the zeolite was not blended, the storage stability was within 2 weeks, while the epoxy resin of the present invention was used. In Examples 1 to 7, which are compositions, the storage stability exceeds 3 months, and is much longer than the comparative examples. As shown in Table 1 above, the epoxy resin composition of the present invention has not only low-temperature curability at a sufficiently practical level but also other adhesive properties,
It has been confirmed that the electrical insulation properties also maintain the original properties of the epoxy resin.

[0040]

The epoxy resin composition of the present invention is excellent in both storage stability and low-temperature curability. For example, it can be stably stored at 40.degree. C. for 3 months or more and at 120.degree.
Shows the ability to cure within 3 minutes at ~ 150 ° C.
Furthermore, storage stability or low-temperature curability can be maintained regardless of the selection of the components such as epoxy resin, diluent, and filler, and the adoption of a mixing method that is advantageous for homogenizing three rolls. It is not damaged unlike the epoxy resin composition of the above.

Claims (2)

[Claims] (1) an epoxy resin having two or more epoxy groups in one molecule; (2) a solid-dispersed amine adduct latent curing agent; (3) an alkoxide compound of titanium, zirconium or boron; An epoxy resin composition comprising zeolite. 2. A metal alkoxide compound content of 0.1 to 20 parts by weight and a zeolite content of 1 to 100 parts by weight based on 100 parts by weight of an epoxy resin having two or more epoxy groups in one molecule. The epoxy resin composition according to claim 1, wherein the amount is part by weight.