JPS623168B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an epoxy resin composition, which aims to have low viscosity, good workability, and good storage stability, as well as excellent flexibility and electrical properties after curing. An object of the present invention is to provide an epoxy resin composition that can give a strong cured product. Epoxy resins are currently very popular as adhesives, coating materials, cast products, and molded products because their cured products have excellent adhesive strength, mechanical strength, electrical insulation, and chemical resistance. Widely used. However, commonly used epoxy resins have a high viscosity, which has the drawback of poor workability during casting and impregnation operations of the epoxy resin. Furthermore, cured products of epoxy resins are insufficient in flexibility. In order to eliminate the above-mentioned drawbacks, reactive diluents such as phenyl glycidyl ether, styrene oxide, cresyl glycidyl ether, butyl glycidyl ether, polypropylene diglycidyl ether, dimer acid diluent, etc. are added to the epoxy resin (prepolymer). A reactive flexibility-imparting agent (reactive diluent and reactive flexibility-imparting agent are collectively referred to as "modifier") such as glycidyl ester and polyester polyol is added. However, each of these modifiers has various drawbacks. In other words, since reactive diluents generally have low molecular weights, some of them evaporate before reacting with the prepolymer during curing, causing problems in terms of odor and toxicity. When the epoxy resin composition is cured, shrinkage occurs, and at the same time, the solvent resistance of the cured product deteriorates and the adhesiveness decreases, or the cured product (reactive diluent in the cured product) may cause irritation to the skin. It has disadvantages such as adhesion to the skin and causing inflammation. In addition, some reactive flexibility-imparting agents, even those called reactive flexibility-imparting agents, generally have poor reactivity with epoxy resins, and therefore do not completely react with the resin even after curing. A part or most of the material merely imparts flexibility through the action of a plasticizer. Therefore, adding such a reactive flexibility-imparting agent to an epoxy resin can improve the flexibility of a cured epoxy resin, but it not only causes shrinkage during curing, but also affects the excellent properties of the epoxy resin. It has the disadvantage that adhesive strength, mechanical strength, heat resistance, chemical resistance, etc. deteriorate. In recent years, an epoxy resin composition has been developed that eliminates both the drawbacks of the epoxy resin itself and the drawbacks caused by the addition of the above-mentioned modifier.
(See Publication No. 25572). Such an epoxy resin composition contains 7-ethyl-1.16 as a modifier in the epoxy resin.
- Added diglycidyl ester of hexadecamethylene dicarboxylic acid. However, the epoxy resin composition described in Japanese Patent Publication No. 53-25572 has poor storage stability, especially storage stability at low temperatures. - It has the disadvantage that diglycidyl ester of 16-hexadecamethylene dicarboxylic acid precipitates as crystals. Therefore, if the epoxy resin composition is stored for a long period of time, for example in the winter, 7-ethyl-
It is necessary to heat the epoxy resin composition in which the diglycidyl ester of 1,16-hexadecamethylene dicarboxylic acid has precipitated as crystals to make the diglycidyl ester and the epoxy resin into a uniform solution,
It is extremely inconvenient to handle. It has a low viscosity and good workability, and after curing, it not only provides a strong cured product with excellent flexibility, electrical properties, and chemical resistance, but also has excellent storage stability. Currently, there is a desire to develop an epoxy resin composition that has extremely good storage stability, especially at low temperatures. In view of the current situation, the present inventors have conducted extensive research in order to develop a desired epoxy resin composition.
As a result, it has been found that the intended purpose can be achieved when a compound represented by the following general formula () is used as an epoxy resin component. The present invention was completed based on this knowledge. That is, the present invention is based on the general formula [In the formula -R- is

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】 or

[Formula] is shown. ] It concerns on the epoxy resin composition characterized by containing the compound and hardening|curing agent represented by these. The epoxy resin composition according to the present invention has a significantly low viscosity and can significantly improve workability in curing the composition. Furthermore, the composition of the present invention has excellent storage stability, especially storage stability at low temperatures. Therefore, even if the composition of the present invention is stored for a long period of time at, for example, 0°C, crystals will not precipitate or phase will occur. No separation will occur. Furthermore, when the composition of the present invention is cured, no shrinkage deformation occurs during curing, and it has excellent flexibility, electrical properties, thermal shock resistance, chemical resistance, weather resistance, adhesive strength, and mechanical properties. It is possible to provide a cured product that has excellent properties such as physical strength. Therefore, the epoxy resin composition according to the present invention can be used in a wide range of applications, including adhesives, molded products, cast products, coating agents,
It can be advantageously used in various fields such as lining agents, sealing agents, and potting agents. The compound represented by the above general formula () used as the epoxy resin component in the present invention is a new compound that has not been described in any literature. Specific examples of the compounds represented by the above general formula () are as follows. Γ7-Methyl-7-tetradecene-1,14-dicarboxylic acid diglycidyl ester (compound 1) Γ7-12-dimethyl-7,11-octadecadiene-1,18-dicarboxylic acid diglycidyl ester (compound 2) Γ7- Methyltetradecane-1,14-dicarboxylic acid diglycidyl ester (compound 3) Γ7,12-dimethyloctadecane-1,18-dicarboxylic acid diglycidyl ester (compound 4) Γ6-phenyldodecane-1,12-dicarboxylic acid diglycidyl ester ( Compound 5) Γ7,8-diphenyltetradecane-1,14-dicarboxylic acid diglycidyl ester (Compound 6) Γ6-cyclohexyldodecane-1,12-dicarboxylic acid diglycidyl ester (Compound 7) Γ7,8-dicyclohexyltetradecane-1・
14-dicarboxylic acid diglycidyl ester (compound 8) The compound represented by the above general formula () can be produced by various methods, but one preferred example is a polycarboxylic acid represented by the following general formula () and epichlorohydrin. It is produced by reacting with. [In the formula, -R- is the same as above. ] Specific examples of the polycarboxylic acid represented by the general formula () are as follows. Γ7-methyl-7-tetradecene-1,14-dicarboxylic acid (compound 1a) Γ7-12-dimethyl-7,11-octadecadiene-1,18-dicarboxylic acid (compound 2a) Γ7-methyltetradecane-1,14 -dicarboxylic acid (compound 3a) Γ7,12-dimethyloctadecane-1,18-dicarboxylic acid (compound 4a) Γ6-phenyldodecane-1,12-dicarboxylic acid (compound 5a) Γ7,8-diphenyltetradecane-1,14- Dicarboxylic acid (compound 6a) Γ6-cyclohexyldodecane-1,12-dicarboxylic acid (compound 7a) Γ7,8-dicyclohexyltetradecane-1.
14-dicarboxylic acid (compound 8a) The polycarboxylic acid represented by the above general formula () is a new compound or a known compound, and these can be produced, for example, as follows. Compounds 1a and 2a are obtained by reacting cyclohexanone with hydrogen peroxide in an alcoholic solution in the presence of an acid catalyst, then reacting the resulting alkoxycyclohexyl peroxide with isoprene in the presence of a ferrous salt, and further reacting. Manufactured by hydrolyzing the product. In the reaction between cyclohexanone and hydrogen peroxide, the ratio of the two used is usually 0.5 to 2 times the molar amount of the latter relative to the former. Examples of the acid catalyst include sulfuric acid, phosphoric acid, hydrochloric acid, etc., and it is usually advisable to use about 0.5 to 10 parts of such acid catalysts per 100 parts by weight (hereinafter simply referred to as "parts") of cyclohexanone. Examples of alcohol include methanol, ethanol, propanol, isopropanol, n-butanol, tert-butanol, etc.
It is usually best to use about 200 to 1000 parts. The reaction temperature of the reaction is generally 0 to 30°C,
Reaction time is 5-20 minutes. In the reaction between the alkoxycyclohexyl peroxide produced in this way and isoprene, the ratio of the latter to the former is usually 1 to 3.
It is better to double the molar amount. Examples of ferrous salts include ferrous sulfate, ferrous chloride, ferrous acetate, and ferrous ammonium sulfate salts. It is preferable to use about 2 moles. The reaction temperature is usually -10 to 10°C and the reaction time is 0.5 to 1 hour. In this way, Compound 1a and Compound 2a are produced in the form of esters, and Compound 1a and Compound 2a are produced by hydrolyzing this according to a conventional method. Compound 3a and compound 4a are the compounds obtained above
It is produced by hydrogenating Compound 1a and Compound 2a, respectively, according to a conventional method. Compound 5a and compound 6a are produced by carrying out the same reaction as above using styrene instead of isoprene. Compound 7a and compound 8a are produced by hydrogenating the obtained compound 5a and compound 6a, respectively, according to a conventional method. The reaction between the polycarboxylic acid represented by the above general formula () and epichlorohydrin can be carried out by appropriately adopting the reaction conditions for the conventional reaction between carboxylic acid and epichlorohydrin. For example, polycarboxylic acid and epichlorohydrin may be reacted in the presence of a catalyst such as a tertiary amine or a quaternary ammonium salt. The ratio of polycarboxylic acid and epichlorohydrin used is usually 1 carboxyl group in the former.
The latter amount is preferably 3 to 20 mol, preferably 5 to 10 mol, based on the equivalent amount. Examples of tertiary amines used as catalysts include triethylamine, tri-
n-propylamine, benzyldimethylamine,
Examples of quaternary ammonium salts include tetramethyl ammonium hydroxide, benzyl trimethyl ammonium hydroxide, benzyl trimethyl ammonium chloride, benzyl triethylammonium chloride, benzyl trimethyl ammonium acetate, methyl triethylammonium chloride, and the like. can be mentioned. The amount of the catalyst used is usually 0.02 to 1.0% by weight, preferably 0.1 to 0.3% by weight, based on the total amount of polycarboxylic acid and epichlorohydrin. The reaction temperature in this reaction is usually 80 to 150°C, preferably 90 to 110°C.
℃, and generally this chlorohydrin esterification reaction is completed in about 0.5 to 1 hour. Next, the compound represented by the above general formula () is produced by neutralization with alkali hydroxide and dehydrochlorination, and the compound can be separated by conventional separation means such as filtration, solvent extraction, washing, etc.
It is isolated and purified from the reaction mixture by distillation, recrystallization, etc. A preferred embodiment in which the compound of general formula () is obtained by reacting the above polycarboxylic acid with epichlorohydrin is as follows. That is, a polycarboxylic acid represented by the general formula () and epichlorohydrin in an amount of 3 to 10 times the mole per carboxyl group of the polycarboxylic acid are mixed, and then a catalyst such as a tertiary amine or a quaternary ammonium salt is added. ,
First, in the first step, an addition reaction is carried out at 80 to 110°C to produce the corresponding polycarboxylic acid chlorohydrin ester. The reaction was stopped when the neutralization value became 1 or less, and then immediately the second step was carried out at 80~
At a temperature of 100°C, a concentrated aqueous alkali hydroxide solution (concentration 40-60%) in an excess of 5-30% over the theoretical amount is added little by little to remove hydrochloric acid, and the added water and the produced water are mixed into an azeotrope with epichlorohydrin. Remove as. As soon as possible after dropping the alkali hydroxide
After raising the temperature to 105°C, the reaction is stopped and quickly cooled to room temperature, and the precipitated sodium chloride is separated by filtration. The epichlorohydrin is recovered under reduced pressure, the product is dissolved in an inert organic solvent, the catalyst and traces of sodium chloride are then removed by washing with water, and the inert organic solvent is recovered by heating to about 140°C under reduced pressure. , to obtain the desired compound represented by the general formula (). In the present invention, an appropriate blend of the compound represented by the above general formula () and a conventionally known epoxy resin can also be used as the epoxy resin component. Specifically, conventionally known epoxy resins include bisphenol A, halogenated bisphenols,
A polyglycidyl ether of a polyhydric phenol obtained by reacting a polyhydric phenol such as hydrogenated bisphenol A, bisphenol F, catechol, or resorcinol with epichlorohydrin, or a polyhydric alcohol such as polyethylene glycol or polypropylene glycol is reacted with epichlorohydrin. polyglycidyl ether of a polyhydric alcohol obtained by reacting a polyhydric carboxylic acid such as phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, adipic acid with epichlorohydrin, Examples include epoxy novolak obtained by condensing a novolak type phenolic resin and epichlorohydrin, polyglycidylamine obtained by condensing a polyamine and epichlorohydrin, epoxidized polyolefin, epoxidized polybutadiene, and epoxidized vegetable oil. Such epoxy resins can be used alone or in combination of two or more.
The compounding ratio of the compound represented by the general formula () and the conventionally known epoxy resin is not particularly limited and can be appropriately selected within a wide range. The compound of general formula () is preferably blended in a blend with the epoxy resin in an amount of 5% by weight or more, preferably 20% by weight or more. A curing agent may be added to the composition of the present invention. As the curing agent to be mixed, any conventionally known curing agent can be used, such as aliphatic polyamines such as polymethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, aminoethylethanolamine, m- phenylenediamine,
Aromatic amines such as 4,4'-diaminodiphenylmethane, diaminodiphenyl ether, diaminodiphenyl sulfone, piperidine, morpholine, N
- Secondary amines such as methylpiperazine, triethanolamine, 2-dimethylamino-2-hydroxypropane, hexamethylenetetramine, N.
Tertiary amines such as N'-dimethylpiperazine, N-methylmorpholine, pyridine, 2,4,6-tris(dimethylaminomethyl)phenol, phthalic anhydride, succinic anhydride, maleic anhydride, methyltetrahydrophthalic anhydride , acid anhydrides such as hexahydrophthalic anhydride, 2-ethyl-4-methylimidazole, 1-pentachlorophenyldiethylenetriamine, N・N′-(hexachlorbiphenylene)bis(ethylenediamine), 1・1′ -(hexachlorbiphenylene)bis(diethylenetriamine), tris(alkylamino)silane, and the like. Such curing agents may be used alone or in combination of two or more.
The amount of the curing agent is not particularly limited and can be appropriately selected within a wide range, but it is preferably approximately stoichiometrically equivalent to the sum of the epoxy equivalents of commonly used epoxy resin components. The composition of the present invention may further include curing accelerators such as phenol, chlorophenol, salicylic acid, and imidazoles, alumina, aluminum hydroxide, red phosphorus, silica, talc, clay, mica,
glass flakes, asbestos, calcium carbonate, gypsum,
Various additives such as fillers such as metal powder and inorganic pigments, tar, xylene formaldehyde resin, plasticizers such as pine oil, polyethylene glycol, and dibutyl phthalate, and solvents such as xylene, methyl ethyl ketone, cellosolve, and butanol may be appropriately blended. There is no particular limitation in producing the epoxy resin composition of the present invention, and conventionally known methods can be employed as they are. For example, the compound of general formula () has a cloud point of -
It is a liquid compound with an extremely low viscosity of 5°C or less, so it can be sufficiently kneaded and easily defoamed by simply mixing the compound of general formula (), a curing agent, and other additives and stirring at room temperature. The composition of the present invention can be obtained. The epoxy resin composition of the present invention can be cured within the range of curing conditions for ordinary epoxy resin compositions, for example by appropriately selecting the type and amount of the curing agent depending on the application. Generally, it can be cured at temperatures ranging from room temperature to 200°C. A manufacturing example of a compound represented by the general formula () is listed as a reference example, and further examples are listed. Reference example 1 (a) Put 1500 kg of anhydrous methanol into a reaction vessel equipped with a stirrer, cool it to -5℃, add 400 kg of cyclohexanone and 15 kg of concentrated sulfuric acid, and add 400 kg of 35% hydrogen peroxide solution while stirring. Gradually add the mixture and continue stirring for 10 minutes while maintaining the temperature at -5°C. Dissolve 333 kg of isoprene in this reaction solution,
Next, 1,200 kg of powdered ferrous sulfate (heptahydrate) was gradually added to the reaction solution while maintaining the temperature at 5° C. or lower to cause a reaction. After the reaction, 60 kg of 60% sulfuric acid is added and stirred, and then separated by standing to separate into an upper organic layer and a lower ferric salt layer. The organic layer was washed with dilute sulfuric acid and water and dehydrated to give 7-methyl-7-tetracene-1,14-dicarboxylic acid dimethyl ester and 7,12-dimethyl-7,11-octadecadiene.
Mixture with 1,18-dicarboxylic acid dimethyl ester [Mixing ratio former: latter = 35:65 (weight)] 651
Get Kg. This mixture was hydrolyzed according to a conventional method to obtain a mixture of 7-methyl-7-tetradecene-1,14-dicarboxylic acid and 7,12-dimethyl-7,11-octadecadiene-1,18-dicarboxylic acid [mixture]. Comparison former: latter = 35:65 (weight)〕568Kg
get. (b) In a 500 ml reaction kettle equipped with a dropping tank, thermometer, reflux device and condenser, add the 7
-Mixture of methyl-7-tetradecene-1,14-dicarboxylic acid and 7,12-dimethyl-7,11-octadecadiene-1,18-dicarboxylic acid80
340 kg of epichlorohydrin and 1.4 kg of tetramethylammonium chloride, and heated to 90 to 100°C for 30 minutes with stirring to perform chlorohydrinization. After completion of chlorohydrination, add 48% caustic soda aqueous solution while maintaining the reaction solution at 80±5℃.
Drop 40Kg over 60 minutes. After the reaction is complete, the salt produced is separated by a filtration method, the liquid is washed with water, and excess epichlorohydrin is separated by distillation.
Mixture of 7-methyl 7-tetradecene-1,14-dicarboxylic acid diglycidyl ester and 7,12-dimethyl-7,11-octadecadiene-1,18-dicarboxylic acid diglycidyl ester [Mixing ratio former: latter = 35:65 (weight)] (hereinafter this mixture will be referred to as "compound") at 100°C. Epoxy equivalent: 267, viscosity: 100 cps (25°C) The viscosity is measured using a B-type viscometer (manufactured by Tokyo Keiki Co., Ltd.). The same applies to the following reference examples and examples. Reference Example 2 (a) 7-Methyl-7-tetradecene 1,14-dicarboxylic acid dimethyl ester and 7,12-dimethyl-7,11-octadecadiene-1,18-dicarvone produced in Reference Example 1(a) The mixture with acid dimethyl ester is rectified to give 7,12-dimethyl-7,
11-octadecadiene-1,18-dicarboxylic acid dimethyl ester is isolated, and then this compound is hydrolyzed in a conventional manner to give 7,12-dimethyl-
7,11-octadecadiene-1,18-dicarboxylic acid is obtained. (b) 7,12-dimethyl-7.
11-octadecadiene-1,18-dicarboxylic acid diglycidyl ester (hereinafter this compound will be referred to as "compound") is obtained. Epoxy equivalent: 265, viscosity: 95 cps (25°C) Reference Example 3 (a) 7-Methyl-7-tetradecene-1,14-dicarboxylic acid dimethyl ester and 7,12-dimethyl-7, produced in Reference Example 1(a) A mixture of 11-octadecadiene and 1,18-dicarboxylic acid dimethyl ester is rectified to obtain 7,12-dimethyl-
7,11-octadecadiene-1,18-dicarboxylic acid dimethyl ester is isolated and this compound is then hydrogenated (catalyst: stabilized nickel, pressure 10
Kg/cm ² , temperature 170°C) to obtain 7,12-dimethyloctadecane-1,18-dicarboxylic acid dimethyl ester, and this compound was further hydrolyzed according to a conventional method to obtain 7,12-dimethyloctadecane-1,18-dicarboxylic acid dimethyl ester.
1,18-dicarboxylic acid is obtained. (b) 7,12-dimethyloctadecane-1,18 was prepared in the same manner as in Reference Example 1(b) except that 7,12-dimethyloctadecane-1,18-dicarboxylic acid was used.
- Obtain dicarboxylic acid diglycidyl ester. Epoxy equivalent: 262, viscosity: 90 cps (25°C) Reference Example 4 (a) 6-phenyldodecane-1,12-dicarboxylic acid dimethyl ester and 7,8-diphenyltetradecane-1.
610 kg of a mixture with 14-dicarboxylic acid dimethyl ester [mixing ratio former: latter = 35:65 (weight)] was obtained. This mixture was hydrolyzed according to a conventional method to obtain 6
-Mixture of phenyldodecane-1,12-dicarboxylic acid and 7,8-diphenyltetradecane-1,14-dicarboxylic acid [mixture ratio former: latter =
35:65 (weight)] Obtained 531Kg. (b) 6-phenyldodecane-1,12-dicarboxylic acid and 7,8-diphenyltetradecane-1,14
6-phenyldodecane-1,12-dicarboxylic acid diglycidyl ester and 7,8-diphenyltetradecane-1.
98 kg of a mixture with 14-dicarboxylic acid diglycidyl ester [mixing ratio former: latter = 35:65 (weight)] (hereinafter this mixture will be referred to as "compound") was obtained. Epoxy equivalent: 290, viscosity: 1344 cps (25°C) Reference Example 5 (a) 6-phenyldodecane-1,12-dicarboxylic acid dimethyl ester and 7,8-diphenyltetradecane-1,14- produced in Reference Example 4(a) The mixture with dicarboxylic acid dimethyl ester is rectified to obtain 7,8-diphenyltetradecane-1,14
- Isolate the dicarboxylic acid dimethyl ester and then hydrolyze this compound according to conventional methods to obtain 7.8
-diphenyltetradecane-1,14-dicarboxylic acid is obtained. (b) 7,8-diphenyltetradecane-1,14-
7,8-diphenyltetradecane was prepared in the same manner as in Reference Example 1(a) except that dicarboxylic acid was used.
1,14-dicarboxylic acid diglycidyl ester (hereinafter this compound will be referred to as "compound") is obtained. Epoxy equivalent: 328, viscosity: 950 cps (25°C) Reference Example 6 (a) 6-phenyldodecane-1,12-dicarboxylic acid dimethyl ester and 7,8-diphenyltetradecane-1,14- produced in Reference Example 4(a) Rectifying the mixture with dicarboxylic acid dimethyl ester to obtain 7,8-diphenyltetradecane-1,14
- Isolate the dicarboxylic acid dimethyl ester and then hydrogenate this compound (catalyst: stabilized nickel, pressure 10 Kg/cm ² , temperature 170°C) to 7.8-
Dicyclohexyltetradecane-1,14-dicarboxylic acid dimethyl ester is obtained, and this compound is further hydrolyzed according to a conventional method to obtain 7,8-dicyclohexyltetradecane-1,14-dicarboxylic acid. (b) 7,8-dicyclohexyltetradecane-
Reference example 1 except for using 1,14-dicarboxylic acid
7,8-dicyclohexyltetradecane-1,14-dicarboxylic acid diglycidyl ester is obtained in the same manner as in (b). Epoxy equivalent: 328, viscosity: 930 cps (25°C) Example 1 Viscosity of epoxy resin composition Compound or compound and bisphenol A type resin [trademark Epicote] in the ratio shown in Table 1 below
828, epoxy equivalent: 190, manufactured by Ciel Co., Ltd.] are uniformly mixed and dissolved, and the viscosity of the resulting composition at 23° C. is measured using a Type B viscosity (manufactured by Tokyo Keiki Co., Ltd.).
The results obtained are shown in Table 1.

[Table] From Table 1 above, it can be seen that the compound or the epoxy resin composition containing the compound has a low viscosity and is easy to handle. Similar results are obtained when a compound or compound is used instead of the compound or compound. Example 2 Storage Stability of Epoxy Resin Composition An epoxy resin composition is prepared by varying the mixing ratio of a compound, a compound, or a compound and Epicote 828 and dissolving them uniformly. The resin composition is left at room temperature for 30 days, and the presence or absence of crystal formation and phase separation is examined. The results are shown in Table 2.
In addition, the presence or absence of crystal formation and phase separation when the resin composition is left at 0° C. for 7 days is also examined in the same manner. The results are shown in Table 3. In addition, instead of the compound, compound, compound, or compound, diglycidyl ester of 7-ethyl-1,16-hexadecamethylene dicarboxylic acid (hereinafter referred to as "compound A"), which is considered to be the best among conventional modifiers, is used. The epoxy resin composition blended with ) was similarly examined for the occurrence of crystal formation and phase separation, and the results are also shown in Tables 2 and 3. The meanings of each symbol in Tables 2 and 3 are as follows. ○: Completely transparent △: Turbid ×: Solid in a phase-separated or turbid state Compositions marked with ○ and △ can be used as epoxy resin compositions.

【table】

[Table] From Tables 2 and 3, compounds, compounds,
It can be seen that the compound or the epoxy resin composition blended with the compound exhibits extremely superior compatibility as compared to the epoxy resin composition blended with Compound A, and is particularly excellent in storage stability at low temperatures. Example 3 Production of cured product Epicoat 828, a test compound (a compound of general formula () or a comparative compound), and 4,4'-diaminodiphenylmethane (DDM) were mixed in the proportions shown in Table 4 below, and the mixture was heated at 80°C. and then heated at 120° C. for 2 hours to obtain a cured product. Also Epicoat
828, the test compound, methyltetraphthalic anhydride [trademark HN-2200, manufactured by Hitachi Chemical Co., Ltd.] and 2-ethyl-4-methylimidazole (EMI) were mixed in the proportions shown in Table 5 below, and the mixture was heated to 80°C. for 2 hours, then
A cured product is obtained by heating at 120°C for 2 hours.

【table】

[Table] Compound B in Tables 4 and 5 is a polyglycidyl ether of polypropylene glycol (trademark: DER-732, manufactured by Ciba Corporation) obtained by reacting polypropylene glycol with epichlorohydrin. Example 4 Various physical properties of cured product According to JIS-K-6919, a test piece Tambell No. 1 was prepared from the cured product obtained in Example 3 (Test Nos. 1 to 8), and the tensile speed was 5 m/min. , temperature: 20
The elongation is measured using a measuring device TOM500 at ℃. Further, using a torsion pendulum type viscoelasticity measuring device (manufactured by Resca), the glass transition point is measured under the conditions of a frequency of 3 Hz and a heating rate of 1° C./min. Also, JIS-K-
6911, the cured product obtained in Example 3 (test
Test pieces (80 x 25 x 3 mm) are prepared from Nos. 1 to 8), and the volume resistivity and dielectric constant are measured at room temperature (23°C). These results are shown in Table 6.

[Table] The following can be seen from Table 6. That is, the cured product obtained by curing the composition of the present invention has large elongation (%) and excellent flexibility. Further, as far as the numerical values of the electrical properties (volume resistivity and dielectric constant) of the cured product are concerned, the electrical properties inherent to the epoxy resin are hardly impaired and are even improved in some areas. Cured product obtained in Example 3 above (Test No. 9~
16), the volume resistivity and dielectric constant are measured in the same manner as above. The results obtained are shown in Table 7.

【table】

Table 7 shows that the electrical properties of the cured product obtained by curing the composition of the present invention are comparable to or better than those of the original epoxy resin.

Claims (1)

[Claims] 1. General formula [In the formula, -R- is [formula] [Formula] [Formula] [Formula] [Formula] [Formula] Indicates [Formula] or [Formula]. ] An epoxy resin composition characterized by containing a compound represented by these and a curing agent.