JPH0733958A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To provide an epoxy resin compsn. for improving the flexibility of not only epihalohydrin-bisphenol type but also novolac and cycloaliphatic type of epoxy resins. CONSTITUTION:An epoxy resin compsn. is prepared by blending 95 to 5 pts.wt. of (a) an epoxy resin having one or more epoxy groups in the molecule with 5 to 95 pts.wt. of (b) an epoxy-modified block copolymer comprising a polymer block (A) consisting mainly of a vinyl aromatic compd. and a polymer block (B) consisting mainly of a conjugated diene compd. or a partly hydrogenated diene compd. The resultant epoxy resin compsn. can be cured with a commonly used hardener such as acid anhydride, aliphatic amine, aromatic amine, novolac phenol and dicyan-diamide to form a cured product with high flexibility.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an epoxy resin composition having excellent flexibility.

[0002]

2. Description of the Related Art Epoxy resin is a compound having a highly reactive epoxy group, and by utilizing this reactivity, it is used in many fields such as coating field, adhesive field and electric field. The epoxy resin currently used is a so-called epibis type epoxy resin produced by reacting bisphenol A and epichlorohydrido in the presence of an alkali.
The main products are novolac epoxy resins produced from novolac phenol and epichlorohydrin, and other alicyclic aliphatic epoxy resins. These epoxy resins have mechanical strength, adhesive strength, surface smoothness, water resistance, electrical characteristics,
It is used in a wide range by taking advantage of various characteristics such as curability.

However, many performances are still required in order to further utilize the characteristics of the epoxy resin. One of them is the requirement for flexibility. In order to improve the flexibility of ordinary epibis type epoxy resin,
Attempts have been made to add acrylonitrile-butadiene rubber or the like (Japanese Patent Publication No. 55-33732, Japanese Patent Publication No. 57-30).
No. 133).

However, although an acrylonitrile-butadiene copolymer can improve impact resistance and adhesive peel strength to some extent, its level is not sufficient, and
There is a problem that it tends to cause thermal deterioration over time. In order to improve this, JP-A-57-149369 and JP-A-57-149370 disclose that an epoxy resin contains (1) a block composed of a monovinyl aromatic compound polymer and (2) a conjugated diolefin polymer. A composition having excellent adhesiveness has been proposed by adding a modified block copolymer obtained by geraching an unsaturated carboxylic acid to a block copolymer consisting of But,
A composition containing these was not always satisfactory because the adhesive strength was lowered and the appearance was deteriorated due to foaming during the process of thermosetting or heating conditions thereafter.

[0005]

However, these rubber materials are still unsatisfactory because of poor compatibility or lack of sufficient flexibility.

[0006]

Therefore, the inventors of the present invention have made intensive studies and found that by using an epoxy-modified block polymer, not only epibis type epoxy but also novolak epoxy resin, cycloaliphatic epoxy, etc. can be used. The inventors have found that the flexibility can be improved and have reached the present invention.

That is, according to the present invention, "(a) 95 to 5 parts by weight of an epoxy resin having one or more epoxy groups in one molecule and (b) a polymer mainly containing vinyl aromatic in the same molecule. Mixing 5 to 95 parts by weight of an epoxy-modified block polymer of a block copolymer composed of the block (A) and a polymer block (B) mainly containing a conjugated diene compound or a partially hydrogenated conjugated diene compound And an epoxy resin composition ”.

Next, the present invention will be described in more detail. The epoxy resin (a) having one or more epoxy groups in one molecule used in the present invention is a generally known epoxy resin and is not particularly limited. Examples thereof include bisphenol A type epoxy resin, bisphenol F type epoxy resin, cresol novolac type epoxy resin, alicyclic epoxy resin, phenol novolak type, and the like, with Shell's trade name Epicoat 82 being particularly preferable.
8, Epicoat 1001, Epicoat 1004, Epicoat 1009, Epicoat 828, etc., or their equivalents, for example, Epi Nippon 830 manufactured by Dainippon Ink and Chemicals, or 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane. Examples of the epoxy resin include carboxylate [trade name: Celoxide 2021 manufactured by Daicel Chemical Industries, Ltd.], which may be used alone or as a mixture of two or more kinds.

Examples of the vinyl aromatic compound constituting the block polymer used in the present invention include styrene and α
-Methylstyrene, vinyltoluene, p-tertiary butylstyrene, divinylbenzene, p-methylstyrene,
1 or 2 of 1,1-diphenylstyrene
One or more kinds can be selected, and styrene is preferable. Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,
One or more of 3-butadiene, piperylene, 3-butyl-1,3-octadiene, phenyl-1,3-butadiene, etc. are selected, among which butadiene,
Isoprene and combinations thereof are preferred.

The block copolymer referred to herein is a block copolymer composed of a polymer block A mainly containing a vinyl aromatic compound and a polymer block B mainly containing a conjugated diene compound. The copolymerization ratio of the group compound and the conjugated diene compound is 5/95 to 70/30, and the polymerization ratio of 10/90 to 60/40 is particularly preferable.

The block copolymer used in the present invention has a number average molecular weight of 5,000 to 600,000, preferably 1.
It is in the range of 0000 to 500,000, and the molecular weight distribution [ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) (Mw / Mn)] is 10 or less. The molecular structure of the block polymer may be linear, branched, radial or any combination thereof. For example, A-B-A, B -A-B-A, (A-B-) 4 S
It is a vinyl aromatic compound-conjugated diene compound block polymer having a structure such as i, A-B-A-B-A. Further, the unsaturated bond of the conjugated diene compound of the block polymer may be partially hydrogenated.

As the method for producing the block polymer used in the present invention, any method can be used as long as it has the above-mentioned structure. For example, Japanese Patent Publication No. 40-2
No. 3798, Japanese Patent Publication No. 43-17979, Japanese Patent Publication No. 46-
A vinyl aromatic compound-conjugated diene compound block copolymer can be synthesized in an inert solvent using a lithium catalyst or the like by the method described in JP-A-32415 and JP-B-56-28925. Furthermore, Japanese Examined Japanese Patent Publication No. 42-87
A portion to be hydrogenated in the presence of a hydrogenation catalyst in an inert solvent by the method described in JP-A-04, JP-B-43-6636, or JP-A-59-133203, and used for the present invention. It is possible to synthesize a block copolymer that has been hydrogenated.

In the present invention, the epoxy-modified block copolymer used in the present invention can be obtained by epoxidizing the above block copolymer.

The epoxy-modified block copolymer in the present invention can be obtained by reacting the above block copolymer with an epoxidizing agent such as hydroperoxides and peracids in an inert solvent.

Examples of peracids include formic acid, peracetic acid, perbenzoic acid and trifluoroperacetic acid. Of these, peracetic acid is industrially produced in large quantities and is available at low cost.
It is also a preferred epoxidizing agent because of its high stability.

The hydroperoxides include hydrogen peroxide, tertiary butyl hydroperoxide, cumene peroxide and the like.

A catalyst may be used in the epoxidation, if necessary.

For example, in the case of peracid, an alkali such as sodium carbonate or an acid such as sulfuric acid can be used as a catalyst. In the case of hydroperoxides, a catalytic effect can be obtained by using a mixture of tungstic acid and caustic soda with hydrogen peroxide, an organic acid with hydrogen peroxide, or molybdenum hexacarbonyl with tert-butyl hydroperoxide. You can There is no strict regulation on the amount of epoxidizing agent and the optimum amount in each case depends on such variables as the particular epoxidizing agent used, the degree of epoxidation desired, the individual block copolymers used, etc. .

The inert solvent can be used for the purpose of reducing the viscosity of the raw material and stabilizing it by diluting the epoxidizing agent. In the case of peracetic acid, aromatic compounds, ethers, esters and the like can be used. Can be used. Particularly preferred solvents are hexane, cyclohexane, toluene, benzene, ethyl acetate, carbon tetrachloride, chloroform. There are no strict restrictions on the epoxidation reaction conditions. The reaction temperature range that can be used depends on the reactivity of the epoxidizing agent used. For example, peracetic acid is preferably 0 to 70 ° C., the reaction is slow below 0 ° C., and the decomposition of peracetic acid occurs above 70 ° C. Also, tertiary butyl hydroperoxide, which is an example of hydroperoxide
In the molybdenum dioxide diacetylacetonate system, 20 ° C to 150 ° C is preferable for the same reason. No special manipulation of the reaction mixture is necessary, for example the mixture may be stirred for 2-10 hours. Isolation of the obtained epoxy-modified copolymer by a suitable method, for example, a method of precipitating with a poor solvent, a method of adding the polymer into hot water under stirring and distilling off the solvent, a direct desolvation method, etc. It can be carried out.

The degree of epoxidation of the epoxy-modified block polymer in the present invention is calculated by the following formula after titration with hydrobromic acid.

[0021] The epoxy equivalent of the epoxy-modified block polymer in the present invention is 140 to 2700, preferably 200 to 2000.

When the epoxy equivalent is more than 2700, the dispersibility with the resin becomes poor. On the other hand, when the epoxy equivalent is less than 140, the rubber elasticity of the epoxy-modified block polymer decreases, which is not preferable.

As the curing agent used in the present invention, known curing agents used for epoxy resins can be used, and amines, polyamide resins, acid anhydrides, polymercaptan resins, novolac resins, dicyandiamide, boron trifluoride can be used. And the amine complex of Here, the amines include the following.

Diethylenetriamine, triethylenetetramine, mensendiamine, metaxylylenediamine,
Aliphatic polyamines such as bis (4-amino-3-methylcyclohexyl) methane and adducts of the aliphatic polyamines with known epoxy compounds, reaction products with acrylonitrile, and reaction products with ketones. Metaphenylenediamine,
Aromatic polyamines such as diaminodiphenylmethane, diaminodiphenyl sulfone and diaminodiphenyl sulfide, and adducts of the aromatic polyamines with known epoxy compounds. Secondary and tertiary amines such as tris (dimethylaminomethyl) phenol, piperidine, imidazole and its derivatives, and salts thereof. And mixtures of said amines. The polyamide resin includes a reaction product of a fatty acid such as fatty acid, dimer acid and trimer acid with an aliphatic polyamine.

The acid anhydrides include the following:

Phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, anhydrous Mixtures of acid anhydrides such as methyl nadic acid, succinic anhydride, dodecenyl succinic anhydride, succinic anhydride and the like.

Novolak resins include low molecular weight resinous products made by condensation of phenol or a mixture of phenol and cresol, dihydroxybenzene and formaldehyde.

As the amine complex of boron trifluoride, monoethylamine, piperidine, aniline, butylamine,
Included are complexes of boron trifluoride with low molecular weight amine compounds such as dibutylamine, cyclohexylamine, dicyclohexylamine, tributylamine, triethanolamine.

Other curing agents include salts of super strong acids such as boron tetrafluoride, phosphorus hexafluoride and arsenic hexafluoride, such as diazonium salts, iodonium salts, bromonium salts and sulfinium salts.

The epoxy resin composition of the present invention contains silica,
Gypsum, quartz powder, calcium carbonate, kaolin, clay, mica, alumina, hydrated alumina, talc, dolomite,
Various additives such as fillers such as zircon, silicic acid compounds, titanium compounds, molybdenum compounds and antimony compounds, pigments, antiaging agents and the like can be added.

The epoxy resin composition of the present invention comprises (i) 1
Epoxy resin having one or more epoxy groups in the molecule 9
5 to 5 parts by weight (b) Polymer block (a) mainly composed of vinyl aromatic and polymer block mainly composed of conjugated diene compound or partially hydrogenated conjugated diene compound in the same molecule It is obtained by mixing 5 to 95 parts by weight of an epoxy-modified block polymer of the block copolymer consisting of (b). Preferably (a) 80 to 20
Parts by weight, (b) 20 to 80 parts by weight.

If (a) is 5 parts by weight or less, the characteristics of (a) cannot be maintained, and if (b) is 5 parts by weight or less, sufficient flexibility cannot be obtained. The mixing of (a) and (b) can be performed in a molten state. Alternatively, they may be dissolved in a suitable solvent such as butyl acetate, toluene, benzene, etc. and mixed. Also, so-called dry blending may be performed in a powder state.

Next, the present invention will be described with reference to examples.

<< Production Example 1 / Preparation of Epoxy-Modified Block Polymer >> A block copolymer of polystyrene-polybutadiene-polystyrene [Japan Synthetic Rubber Co., Ltd.] was used in a jacketed reactor equipped with a stirrer, a reflux condenser and a thermometer.
Product name: TR2000] 300 g, ethyl acetate 15
00 g was charged and dissolved.

Then, 169 g of a 30 wt% ethyl acetate solution of peracetic acid was continuously added dropwise, and an epoxidation reaction was carried out at 40 ° C. for 3 hours while stirring. The reaction solution was returned to room temperature and taken out of the reactor, a large amount of methanol was added to precipitate the polymer, which was filtered, washed with water and dried to obtain an epoxy-modified polymer. The obtained epoxy-modified polymer is referred to as polymer A (epoxy equivalent of polymer: 465).

Production Example 2 / Preparation of Epoxy-Modified Block Polymer A polystyrene-polybutadiene-polystyrene block copolymer [Japan Synthetic Rubber Co., Ltd.] was used in a jacketed reactor equipped with a stirrer, a reflux condenser and a thermometer.
Product name: TR2400] 300 g, ethyl acetate 15
00 g was charged and dissolved.

Subsequently, 113 g of a 30% by weight ethyl acetate solution of peracetic acid was continuously added dropwise, and an epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring. The reaction solution was returned to room temperature and taken out of the reactor, a large amount of methanol was added to precipitate the polymer, which was filtered, washed with water and dried to obtain an epoxy-modified polymer. The obtained epoxy-modified polymer is referred to as polymer B (epoxy equivalent of polymer: 690).

Production Example 3 / Preparation of Epoxy-Modified Block Polymer A polystyrene-polybutadiene-polystyrene block copolymer [manufactured by Shell Kagaku Co., Ltd.] was used in a jacketed reactor equipped with a stirrer, a reflux condenser and a thermometer. ,
Product name: Califlex D1122] 300 g and cyclohexane 1500 g were charged and dissolved. Then, 177 g of a 30 wt% ethyl acetate solution of peracetic acid was continuously added dropwise, and an epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring. The reaction solution was returned to room temperature and taken out of the reactor, a large amount of methanol was added to precipitate the polymer, which was filtered, washed with water and dried to obtain an epoxy-modified polymer. The obtained epoxy-modified polymer is referred to as polymer C (epoxy equivalent of polymer: 44
3).

Production Example 4 / Preparation of Epoxy Modified Block Polymer >> A polystyrene-polyisoprene-polystyrene block copolymer was added to a jacketed reactor equipped with a stirrer, a reflux condenser and a thermometer [Shell Chemical Co., Ltd.]. Made by
Product name: Califlex TR1111] 300 g and cyclohexane 1500 g were charged and dissolved. Then, 222 g of a 30 wt% ethyl acetate solution of peracetic acid was continuously added dropwise,
The epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring. The reaction solution was returned to room temperature and taken out of the reactor, a large amount of methanol was added to precipitate the polymer, which was filtered, washed with water and dried to obtain an epoxy-modified polymer. The obtained epoxy-modified polymer is referred to as polymer D (epoxy equivalent of polymer: 35
6).

Production Example 5 / Preparation of Epoxy-Modified Block Polymer >> A block copolymer of polystyrene-polybutadiene-polystyrene in a jacketed reactor equipped with a stirrer and a thermometer [manufactured by Nippon Synthetic Rubber Co., Ltd., product Name: TR
2000] 300 g and cyclohexane 3000 g were charged and dissolved, and the temperature was 60 ° C. and 40 ml of di-P-tolylbis (1-cyclopentadienyl) titanium / cyclohexane solution (concentration 1 mmol / liter) and n-butyl were used as hydrogenation catalysts. Lithium solution (concentration 5 mmol /
Liter) 8 ml and 0 ° C, 2.0 kg / cm ²
Add a mixture under hydrogen pressure, hydrogen partial pressure 2.5 kg
The reaction was performed at / cm ^{2 for} 30 minutes. The obtained partially hydrogenated polymer solution was dried under reduced pressure to remove the solvent (hydrogenation rate of the entire butadiene portion was 30%).

300 g of this partially hydrogenated polymer and 1500 g of cyclohexane were charged and dissolved. Then 30 of peracetic acid
300 g of a wt% ethyl acetate solution was continuously added dropwise, and an epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring. The reaction solution was returned to room temperature and taken out of the reactor, a large amount of methanol was added to cause the polymer to break out, and the polymer was separated by filtration, washed with water and dried to obtain an epoxy-modified polymer. The obtained epoxy-modified polymer is referred to as polymer E (epoxy equivalent of polymer 275).

[Examples 1 to 5] 20 parts each of the epoxy-modified block polymers A to E obtained in the production example and Epicoat 10
01 (Epoxy equivalent 450-500, made by Yuka Shell)
100 parts and well kneaded using a Labo Plastomill (Toyo Seiki), the resulting kneaded product was transferred to an open roll at 60 ℃, all epoxy groups (epoxy resin and epoxy contained in the epoxy modified block copolymer An equivalent amount of dicyandiamide and 7% benzyldimethylamine of dicyandiamide were added to the total amount of groups) and kneaded for 10 minutes to obtain an epoxy resin composition. Then these 10
Transfer to a heat press machine at 0 ° C and sandwich it with a Teflon sheet.
Preheating for 1 minute and pressurization for 2 minutes (50 kgf / cm ² ) were applied to obtain an uncured sheet having a thickness of 0.2 mm. This sheet was sandwiched between soft aluminum plates cleaned with 0.2 mm thick acetone, and the thickness of the epoxy resin composition layer was 0.1 mm.
Compressed (pressure 20 kgf / cm ² ) until it reaches 190 ℃
And held for 15 minutes to obtain an adhesive laminate.

A test piece having a width of 25 mm was cut out from this adhesive laminate, and the T-shaped peel strength was measured at a tensile speed of 200 mm / min at a temperature of 23 ° C. and 100 ° C. Second result
Shown in the table. Further, the uncured sheet is laminated between 0.6 mm-thick chemical conversion treated steel sheets so that the adhesive surface has a width of 25 mm and a length of 15 mm, and compressed until the thickness of the epoxy resin composition layer becomes 0.1 mm. (Pressure 20 kg / cm ² )
The test piece for tensile shear test was obtained by holding at 190 ° C. for 15 minutes. Tensile shear rate 2 mm / min, temperature 23 ° C and 100
Its strength was measured at ° C. The results are shown in Table 1.

Comparative Examples 1, 2, and 3 Unmodified block copolymers as starting materials for the epoxy-modified block copolymers A, B, and D of Example 1 were prepared by the same method and blending ratio as in Example 1. The cured sheet was adjusted to obtain an adhesive laminate and a test piece as in Example 1. Next, the T-peel strength and tensile shear strength were determined under the same conditions as in Example 1. The results are shown in Table 1.

Comparative Example 4 The epoxy resin Epicoat 1001 used in Example 1 was used alone, the same curing agent as in Example 1 was used, and the same formulation as in Example 1 was used.
The mixture was kneaded at 15 ° C. for 15 minutes, and then hot pressed at 80 ° C. to obtain an uncured sheet. This was bonded in the same manner as in Example 1 and tested in the same manner as in Example 1. The results are shown in Table 1.

[Example 6] As an epoxy resin, Epicoat 828 (epoxy equivalent: 184 to 194, manufactured by Yuka Shell) and the epoxy-modified block polymer E of Production Example 3 were used.
The ratio was adjusted according to the following procedure so as to obtain the ratio shown in the table.
First, take an epoxy resin and a small amount of a toluene / tetrahydrofuran mixture in a container, add 10 to 30% toluene solution of an epoxy-modified block polymer and an unmodified block polymer while stirring with a homogenizer, and add the epoxy resin and the block. Toluene / tetrahydrofuran was added so that the total concentration of the copolymer would be about 50%, and they were mixed uniformly.

This mixed solution was transferred to a rotary evaporator and heated under stirring at 60 ° C./60 rpm while stirring under reduced pressure to remove toluene and tetrahydrofuran at 150 ° C./1.
Distillation was carried out until the volatile matter in the time became 0.2% or less. To the obtained composition, triethylenetetramine in an equivalent amount to all epoxy groups (total amount of epoxy groups of epoxy resin and epoxy-modified block polymer) was added, and the mixture was added at 80 ° C. for 3 hours and then at room temperature for 7 days. The Izod impact strength (JIS K-6911) of the cured product cured by curing, the average dispersed particle size of the block polymer by an electron microscope, and the weight increase rate when immersed in methyl ethyl ketone (3 days at room temperature) were examined. Is shown in Table 2.

<Comparative Example 5> The epoxy resin of Example 6 was used alone, and the same curing agent and compounding recipe as in Example 6 were used and cured in the same manner as in Example 6 to obtain the properties of a cured product. Example 6
It investigated with the same method and conditions. The results are shown in Table 2.

<Comparative Example 6> Epoxy resin 10 of Example 6
A curing agent-free composition was prepared by the same procedure and method as in Example 6, except that 0 part and 20 parts of a maleic anhydride-modified block polymer (Tuftec M1913, manufactured by Asahi Kasei) were prepared.
According to Example 6, the properties of a cured product obtained by curing the same type of curing agent and compounding formulation as in Example 6 were examined. The results are shown in Table 2.

Comparative Example 7 Epoxy Resin 10 of Example 6
Izod impact of a cured product obtained in the same manner as in Example 6 by blending 0 part of 20 parts of liquid carboxyl-terminated acrylonitrile-butadiene copolymer and 12 parts of triethylenetetramine as a curing agent. The strength and the rate of weight increase by immersion in methyl ethyl ketone were investigated. The results are shown in Table 2. As can be seen from Table 3, the epoxy resin composition of the present invention was excellent in impact resistance and chemical resistance.

[Example 7] The epoxy-modified block polymer obtained in Production Example 5 was micronized by a freeze pulverization method or a spray drying method to obtain a powder having an average diameter of 50 µm and 20 µm. Epoxy resin 1 using 20 parts of this powder in Example 6
It was dispersed in 00 parts to obtain a cured product of the epoxy resin composition according to the curing agent, the compounding standard and the curing conditions shown in Example 6. When these Izod impact strengths were measured, it was 6.3 kg · cm / cm when the average diameter of the epoxy-modified block polymer was 50 μm and 7.2 k when it was 20 μm.
The value in g / cm / cm is shown and combined with Table 2, it is understood that the particle size of the epoxy-modified block polymer in the cured product has a preferable range.

[Example 8] and [Comparative Examples 8 and 9] Comparison was made with a cured product (Example 8) of an epoxy resin composition containing 20 parts of the epoxy-modified block polymer E relative to 100 parts of the epoxy resin of Example 6. A cured product of the epoxy resin composition containing the maleic anhydride block copolymer of Example 6 (Comparative Example 8) and a cured product of the epoxy resin composition containing the carboxyl-terminated acrylonitrile butadiene copolymer of Comparative Example 7 (Comparative Example Hold 9) at 150 ℃ for 1,000 hours
The flexural modulus was measured according to IS K6911. Moreover, the appearance was changed by holding at 230 ° C. for 2 hours.
The results are shown in Table 3.

As shown in Table 3, the epoxy resin composition of the present invention has an initial elastic modulus higher than that of Comparative Example 9 containing both-terminal-carboxylated acrylonitrile-butadiene copolymer, but when kept at high temperature. In addition, there is little change, and even when the maleic anhydride-modified block copolymer of Comparative Example 8 is included, appearance change such as swelling does not occur even at higher temperatures, and excellent flexibility is obtained. Has heat resistance.

[0054]

The epoxy resin composition obtained by the present invention can be cured by a commonly used epoxy curing agent such as acid anhydride, aliphatic amine, aromatic amine, novolac phenol, dicyandiamide and the like. A cured product having excellent flexibility can be obtained.

Table 1 Tensile strength T-shaped peel strength (kgf / cm ² ) (kgf / 25mm) Epoxy resin composition 23 ° C 100 ° C 23 ° C 100 ° C Example 1 Epikote 1001 / EA 220 50 8.5 6.0 2 Epikote 1001 / EB 230 60 8.4 6.5 3 Epikote 1001 / EC 210 55 8.3 6.0 4 Epikote 1001 / ED 205 45 8.4 5.8 5 Epikote 1001 / EE 225 52 8.5 6.7 Comparative Example 1 Epikote 1001 / A before epoxidation 110 20 2.8 1.3 2 Epikote 1001 / B 95 18 2.0 1.3 3 Epikote 1001 / before epoxidation D 150 20 3.9 3.4 4 Epikote 1001 only 175 40 2.3 4.1 Table 2 [1] [2] [3] [4] [5] Example 5 100 10 4.8 1.0 1.0 100 20 8.8 1.5 2.4 100 40 10.9 2.0 3.2 Comparative example 5 100 − 2.7 − 0.8 6 100 20 4.0 1.8 9.7 (M-SEBS) 7 100 20 4.5 − 34.0 (CTBN) (blank space) Table 2 M-SEBS is a maleic anhydride-modified block copolymer CTBN is carboxylated butadiene / acrylonitrile rubber at both ends [1]: Epoxy resin (parts by weight) [2]: Epo Xy-modified block copolymer (parts by weight) [3]: Izod impact strength (kg · cm / cm) [4]: Average dispersed particle size (μm) [5]: Weight increase rate (%) by immersion in methyl ethyl ketone table 3 [1] [2] [3] Example 8 Composition of Example 6 180 190 No change Comparative Example 8 Composition of Comparative Example 6 190 202 Change Yes Comparative Example 9 Composition of Comparative Example 7 145 220 No change Table 3, [1]: initial value of flexural modulus (kg / mm ² ) [2]: value of flexural modulus (kg / mm ² ) after 150 ° C for 1000 hours [3]: when kept at 230 ° C Change in appearance (hereinafter referred to as margin)

Claims (2)

[Claims] 1. A polymer block (A) mainly composed of vinyl aromatic in the same molecule as (b) 95 to 5 parts by weight of an epoxy resin having one or more epoxy groups in one molecule.
And 5 to 95 parts by weight of an epoxy-modified block polymer of a block copolymer comprising a conjugated diene compound or a polymer block (B) mainly containing a conjugated diene compound or a partially hydrogenated conjugated diene compound. An epoxy resin composition characterized by: 2. The epoxy equivalent of the component (b) is 140 to 2700.
The epoxy resin composition according to claim 1, which is