JP2015108105A - Liquid epoxy resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid epoxy resin composition having excellent mechanical characteristics, voltage resistance, and electrical insulation properties; and to provide a liquid epoxy resin which gives higher heat resistance and exhibits more excellent flow properties than that of the same amount of a conventional-heat resistant material novolac type epoxy resin addition system as that of the liquid epoxy resin.SOLUTION: A liquid epoxy resin composition contains: an epoxy resin 1-[α-methyl-α-(4'-glycidoxyphenyl)ethyl]-4-[α',α'-bis(4''-glycidoxyphenyl)ethyl]benzene; a liquid epoxy resin; a glycidyl ether compound of a polyfunctional aliphatic alcohol; an acid anhydride-based or amine-based curing agent; and a curing accelerator.

Description

  The present invention relates to a liquid epoxy resin composition.

  This liquid epoxy resin composition has low viscosity and good impregnation properties, and a cured product obtained from the resin composition is excellent in heat resistance, mechanical strength, moisture resistance, and electrical insulation. It is suitable as an impregnating agent for electrical and electronic parts such as jigs and structural parts, coils and film capacitors in the electrical field such as copying machines and printers, and in the automotive field.

Epoxy resins can be combined with many different materials such as metal, glass fiber, paper, etc. because they have small shrinkage during reaction and excellent adhesion. In addition, the cured product has material properties such as electrical insulation, mechanical strength, heat resistance, moisture resistance, and adhesiveness, so it is widely used as a casting material for structural insulators of electrical equipment and electronic parts. .
In recent years, products for such applications have been reduced in size, and the thermal load received by individual parts around the heating element has increased, and therefore, higher heat resistance is required. Since the epoxy resin composition requires excellent mechanical properties, voltage resistance, and electrical insulation, a solventless composition is usually used. For this reason, in order to improve the impregnation property, low viscosity and good flowability are also desired.

In order to increase the heat resistance of the epoxy resin, a method of adding a trifunctional or higher polyfunctional epoxy resin is generally known. Novolac epoxy resins are mainly used, but novolac epoxy resins always have a distribution in molecular weight because of the manufacturing method. The low molecular weight and high molecular weight portions have the disadvantage of lowering the heat resistance, and the high molecular weight portion has a disadvantage of increasing the viscosity, and there is a problem in utilizing both for higher heat resistance and viscosity.
An epoxy resin having a naphthalene skeleton has also been proposed as a heat resistant material (Patent Document 1 Japanese Patent Application Laid-Open No. 2001-11286), but the cured product is improved in heat resistance but is not satisfactory in moisture resistance and impact resistance. Its use is limited.

JP 2001-11286 A Conventionally, for the purpose of reducing the viscosity of an epoxy resin composition, various epoxy resin diluents such as monoglycidyl ether such as butyl glycidyl ether and phenyl glycidyl ether, 1,6-hexanediol diglycidyl ether, glycidyl neodecanoate, etc. The viscosity (25 ° C.) of the epoxy resin composition formed by blending such an epoxy resin diluent is about 350 to 400 mPa · s, but the heat resistance temperature (HDT) is about 70 to 95 ° C. is there.

Although the above epoxy resin diluent has a certain effect on reducing the viscosity of the epoxy resin composition, the cured product of the epoxy resin composition has significantly reduced heat resistance, moisture resistance, There were problems such as insufficient strength and electrical characteristics.
Therefore, in order to cope with the heat load that increases with the miniaturization of electrical equipment and electronic components, it is strongly required to achieve a lower viscosity of the epoxy resin composition than before, together with excellent heat resistance. .

  The present invention has a low viscosity, excellent flowability at the time of casting, good impregnation in various parts, and excellent heat resistance, mechanical strength, voltage resistance, electrical properties without lowering curability. It aims at providing the liquid epoxy resin composition which has insulation and adhesiveness.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have achieved the intended purpose by applying a predetermined amount of a polyfunctional aliphatic alcohol glycidyl compound as a specific polyfunctional epoxy-based compound as a heat-resistant component. The present invention has been found to be achieved, and the present invention has been completed based on such findings.

That is, the liquid epoxy resin composition according to the present invention comprises epoxy resin 1- [α-methyl-α- (4′-glycidoxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″-). Glycidoxyphenyl) ethyl] benzene 100 parts by weight, 0 to 300 parts by weight of liquid epoxy resin, 0 to 25 parts by weight of polyfunctional aliphatic alcohol glycidyl ether compound, acid anhydride or amine curing agent Parts by weight of 0.8 to 1.1 times equivalent to the total equivalent of the epoxy group of the epoxy resin, the liquid epoxy resin, and the glycidyl ether of the polyfunctional aliphatic alcohol, and the curing accelerator 0.5 A liquid epoxy resin composition containing ˜5 parts by weight.
In acid anhydride curing, one equivalent of an epoxy group reacts with one mole of acid anhydride group. For this reason, 1 mole of an acid anhydride group is calculated as 1 equivalent, and the above ratio is shown.

  According to the present invention, a liquid epoxy resin composition having excellent mechanical properties, voltage resistance, and electrical insulation can be obtained. Furthermore, by utilizing a specific heat-resistant component, it is possible to obtain a liquid epoxy resin which gives higher heat resistance and exhibits good flowability than a novolac-type epoxy resin equivalent addition system conventionally used as a heat-resistant component. Moreover, when obtaining the conventional heat resistance, the addition amount of polyfunctional aliphatic alcohol glycidyl ether or the like can be increased, and the flowability can be further improved.

FIG. 1 is a conceptual diagram of a test piece for performing a heat resistance test for obtaining a heat resistance temperature.

Examples of the liquid epoxy resin according to the present invention include liquid bisphenol A type epoxy resin, bisphenol F type epoxy resin and the like, and glycidyl ether type glycidyl ester type epoxy such as phenol novolac epoxy resin and cresol novolac epoxy resin as necessary. A resin, a glycidylamine type epoxy resin, a halogenated epoxy resin, or the like can be mixed and used. In particular, liquid bisphenol A type glycidyl ether, bisphenol F type glycidyl ether and the like are recommended. The addition amount of the liquid epoxy resin is 1- [α-methyl-α- (4′-glycidoxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″ -glycidoxyphenyl) ethyl] benzene 300 parts by weight or less is preferable with respect to 100 parts by weight, and if the addition amount exceeds 300 parts by weight, the heat resistance of the cured product decreases.
As the glycidyl ether compound of a polyfunctional aliphatic alcohol in the present invention, a polyglycidylated product of a polyfunctional aliphatic alcohol is preferable. The polyfunctional aliphatic alcohol is preferably a polyhydric alcohol compound such as trimethylolpropane or glycerin, particularly a compound having three hydroxyl groups. Among these, trimethylolpropane triglycidyl ether and glycerin triglycidyl ether are preferable.
The amount of these components is 1- [α-methyl-α- (4′-glycidoxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″ -glycidoxyphenyl) ethyl] benzene. 0 to 25 parts by weight, more preferably 0 to 20 parts by weight is recommended with respect to 100 parts by weight, and if it exceeds 25 parts by weight, the heat resistance of the cured product is lowered and the desired cured product is obtained. It is difficult to obtain the characteristics.
Examples of the acid anhydride or amine curing agent used in the present invention include the following. That is, as acid anhydride curing agents, acid anhydride curing agents such as hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, and methylnadic acid anhydride are recommended. It applies individually or in combination of 2 or more types as appropriate.

  The compounding amount of the nucleic acid anhydride curing agent is 1- [α-methyl-α- (4'-glycidoxyphenyl) ethyl] -4- [α ', α'-bis (4 "-glycid Xyphenyl) ethyl] benzene and liquid epoxy resin, and parts by weight in a proportion of 0.8 to 1.1 times equivalent to the total equivalent of epoxy groups resulting from the glycidyl ether compound of polyfunctional aliphatic alcohol are recommended. When less than 0.8 equivalents or more than 1.1 equivalents are blended, properties such as moisture resistance, heat resistance, mechanical strength, etc. are deteriorated, which is not preferable in any case.

Examples of amine curing agents used in the present invention include aliphatic polyamines such as diethylenetriamine, triethylenetetramine, N-aminoethylpiperazine, isophoronediamine, 1.3-bisaminomethylcyclohexane, and fatty aromas such as m-xylenediamine. Group amines are recommended and are applied alone or in appropriate combination of two or more.
The compounding amount of the amine curing agent is 1- [α-methyl-α- (4′-glycidoxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″ -glycidoxyphenyl) ethyl. A weight part of 0.8 to 1.1 times equivalent to the total equivalent of epoxies derived from benzene, liquid epoxy resin and glycidyl ether compound of polyfunctional aliphatic alcohol is recommended. If it is less than or exceeds 1.1 equivalents, properties such as moisture resistance, heat resistance and mechanical strength are lowered, which is not preferable in any case.

  As the curing accelerator, various conventionally used curing accelerators can be used, and more specifically, tertiary compounds such as benzyldimethylamine, tris (dimethylaminomethyl) phenol, dimethylcyclohexylamine and the like. Amines, imidazoles such as 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-methylimidazole, N-benzyl-2-ethylimidazole, 1,8-diazabicyclo (5 , 4,0) Diazabicycloalkenes such as undecene-7 and salts thereof such as 2-ethylhexanoate, organometallic compounds such as zinc octylate, tin octylate, aluminum ethylacetone complex, quaternary ammonium Examples include organic phosphine compounds such as compounds and triphenylphosphine. That.

The addition amount of the curing accelerator is 1- [α-methyl-α- (4′-glycidoxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″ -glycidoxyphenyl) ethyl. It is recommended to use 0.5 to 5 parts by weight, preferably 0.8 to 3 parts by weight, based on 100 parts by weight of benzene.
If it is less than 0.5 part by weight, it takes a long time for curing, and workability is lowered, which is not practical. On the other hand, when the amount exceeds 5 parts by weight, heat generation during curing is large, leading to deterioration of the properties of the cured product.

  The liquid epoxy resin composition according to the present invention can be prepared by a known method. For example, a predetermined amount of an epoxy resin, an epoxy resin diluent, an acid anhydride curing agent, a curing accelerator, and a flame retardant, a pigment, a dye, a coupling agent, a surface modifier, etc., as appropriate, And a uniform mixing method using a typical stirrer.

  The cured product obtained from the liquid epoxy resin composition thus obtained is excellent in heat resistance, mechanical strength, moisture resistance, and electrical insulation. It is suitable as an impregnating agent for electrical and electronic parts such as jigs and structural parts, coils and film capacitors in the electrical field such as copying machines and printers, and in the automotive field.

Examples The following examples are given to illustrate the present invention in detail. In addition, as a physical characteristic of the epoxy resin composition in each example, heat resistance, viscosity, and resin flowability were measured by the following methods.

(A) Measurement of heat resistance Heat resistance was measured by a bending test method.
The relationship between the value (X) according to this method and the value (Y) according to the JIS (K-7207) method is Y = 0.882X + 5.52, r2 = 0.998, which is a good correlation.
<Preparation of test piece>
1. The curing agent containing the epoxy resin and the accelerator was left in a 40 ° C. oven for 1 hour (hr).
2. A predetermined amount of a curing agent and an accelerator were added to 50 g of epoxy resin and stirred and mixed to obtain a uniform solution.
3. The obtained homogeneous solution was placed in a deaerator at room temperature and degassed under reduced pressure.
4). After completion of the defoaming operation, the mixture was poured into a flat plate type (260 mm × 200 mm × 3 mm) previously set in a circulation oven at 50 ° C.
5. When pouring was completed, the oven was closed, and curing was performed at a predetermined temperature for a predetermined time.
6). After curing, the cured product was removed from the mold to obtain a flat plate having a thickness of 3 mm. A test piece of 100 to 120 mm × 20 mm × 3 mm was cut out from this flat plate.
<Heat test conditions>
Based on the conceptual diagram of the test piece shown in the conceptual diagram of FIG. 1, the heat resistant temperature was determined by the following procedure.
(1) A load wedge (F = 200 g) is applied to the test piece at the center with a span (L) of 60 mm.
(2) A load is applied for 30 minutes at a predetermined temperature (convection oven). After rapidly cooling the test piece, the amount of deflection is measured.
(3) The measurement temperature is changed and the operation of (2) is repeated to obtain a relationship diagram between the measurement temperature and the deflection amount.
(4) The temperature at which the deflection amount (Y) is 4 mm in the relationship diagram between the temperature and the deflection amount is defined as the heat resistant temperature.

(B) Measurement of viscosity The epoxy resin and the composition were placed in a mayonnaise bottle, warmed in a water bath at a predetermined temperature, and measured with a B-type viscometer.
(C) Flowability of resin A funnel made of polymethylpentene-1 having a thickness of 0.05 mm is attached to a glass flat plate (100 mm × 100 mm × 0.4 mm) that has been installed in a circulating oven at 80 ° C. The resin composition was poured into a funnel and allowed to stand at 80 ° C. for a predetermined time, and then the inflow of the resin into the mold was observed.
In Table 1, o indicates good flowability, x indicates poor flowability, and Δ indicates the middle.

Example 1
645.7 g of epichlorohydrin, 141.3 g of 1- [α-methyl-α (4′-hydroxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″ -hydroxyphenyl) ethyl] benzene and tetramethylammonium 2.73 g of chloride was charged into a 1-liter glass four-necked flask equipped with a stirrer and a reflux apparatus, and allowed to react for 3 hours at 70 ° C. with stirring, after which 48% hydroxylation was maintained while maintaining this temperature. 79 g of an aqueous sodium solution (molar ratio of 2.85 to the above trisphenol) was continuously added dropwise over 2 hours.
At this time, the pressure in the system was reduced to 150 to 250 mmHg, the generated water was removed from the system, and the azeotropic epichlorohydrin was returned to the system. Even after completion of the dropwise addition, water was removed from the system until no more water was observed, and unreacted epichlorohydrin was subsequently distilled out of the system.
To the residue, 230 g of methyl isobutyketone and 230 g of water were added and stirred, and the resulting sodium chloride was transferred to the aqueous phase and allowed to stand, and the separated aqueous phase was removed. Next, 20 g of a 24% aqueous sodium hydroxide solution was added to the oil phase, and the mixture was stirred at 90 ° C. for 2 hours to carry out a second dehydrochlorination reaction.
Thereafter, the oil phase is separated from the aqueous phase, neutralized by adding 76 g of a 30% aqueous sodium dihydrogen phosphate solution, followed by water removal by azeotropic distillation and filtration of the salt by a G4 glass filter. It was.
1- [α-methyl-α- (4′-glycidoxyphenyl) having an epoxy equivalent of 208 g / eq and a softening point of 60 ° C. is completely removed from the oil phase under reduced pressure of 5 mmHg and 150 ° C. 180 g of ethyl] -4- [α ', α'-bis (4 "-glycidoxyphenyl) ethyl] benzene was obtained.

Example 2
Bisphenol A type liquid epoxy resin (R140 manufactured by Mitsui Chemicals, epoxy equivalent 188 g / eq) 66.6 g, trimethylolpropane triglycidyl ether (Epolite 100MF epoxy equivalent 140 g / eq manufactured by Kyoeisha Chemical) in a 300 ml round bottom flask equipped with a stirrer 18. 5 g was added and heated to 90 ° C. to homogenize, and further 100 g of heat resistant resin A synthesized in Example 1 was added in three portions at the same temperature to obtain a uniform mixture (epoxy resin A). The viscosity of the epoxy resin A was 9000 mPa · s at 47 ° C. and 50000 mPa · s at 33 ° C.
3.6 g of N-benzyl-2-methylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.) was added at room temperature to 154.8 g of methylhexahydrophthalic anhydride (HN5500, neutralized equivalent 168 g / eq, manufactured by Hitachi Chemical Co., Ltd.). (Curing agent A) The viscosity of the curing agent A was 70 mPa · s at 25 ° C. After 50 g of epoxy resin A and 44 g of curing agent A were left in an oven at 40 ° C. for 1 hour (hr), 43 g of curing agent A was added to epoxy resin A, and the mixture was stirred and mixed at room temperature to obtain a uniform mixture. The viscosity of this mixture was 1870 mPa · s at 30 ° C. The obtained uniform solution was put into a room temperature defoaming apparatus and defoamed under reduced pressure. After completion of the defoaming operation, the mixture was poured into a flat plate type (260 mm × 200 mm × 3 mm) previously set in a circulation oven at 50 ° C. The flow of the mixture during casting was smooth. After a curing reaction at 80 ° C. for 2 hours (hr), the cured product was taken out of the mold.
There were no problems such as cracks in the cured product during removal. The obtained cured product was sandwiched between glass plates and further cured at 150 ° C. for 3.5 hours (hr).
The heat resistance temperature of the obtained cured product was 165 ° C., and the hardness was 84 (Shore D 28 ° C.).

Example 3
Add 245 g of bisphenol A liquid epoxy resin (R140 manufactured by Mitsui Chemicals, Inc.) to a 500 ml round bottom flask with a stirrer, heat to 90 ° C., and add heat-resistant resin A 105 g synthesized in Example 1 in three portions at the same temperature to be uniform. A mixture (epoxy resin B) was obtained. The viscosity of the epoxy resin B was 4500 mPa · s at 44 ° C. and 25500 mPa · s at 33 ° C.
3.5 g of 1-cyanoethyl-2-ethyl-4-methylimidazole (manufactured by Tokyo Chemical Industry) was added to 290 g of methylhexahydrophthalic anhydride (HN5500, manufactured by Hitachi Chemical Co., Ltd.) at room temperature. (Curing agent B) The viscosity of the curing agent B was 70 mPa · s at 25 ° C. After 50 g of epoxy resin B and 44 g of curing agent B were left in a 40 ° C. oven for 1 hour (hr), 43.0 g of curing agent B was added to epoxy resin B, and the mixture was stirred and mixed at room temperature to obtain a uniform mixture. The viscosity of this mixture was 900 mPa · s at 30 ° C. The obtained uniform solution was put into a room temperature defoaming apparatus and defoamed under reduced pressure. After completion of the defoaming operation, the mixture was poured into a flat plate type (260 mm × 200 mm × 3 mm) previously set in a circulation oven at 50 ° C. The flow of the mixture during casting was smooth. After a curing reaction at 80 ° C. for 2 hours and further at 150 ° C., the cured product was taken out from the mold.
The heat resistance temperature of the obtained cured product was 162 ° C., and the hardness was 85 (Shore D 28 ° C.).

Example 4
To a 500 ml round bottom flask with a stirrer, 245 g of bisphenol A type liquid epoxy resin (R140 manufactured by Mitsui Chemicals, Inc.) was added and heated to 90 ° C. A mixture (epoxy resin B) was obtained. The viscosity of the epoxy resin B was 4500 mPa · s at 44 ° C. and 25500 mPa · s at 33 ° C.
Also, 3.6 g of benzyldimethylamine (manufactured by Wako Pure Chemical Industries, Ltd.) was added to 89.4 g of 1,3-bisaminomethylcyclohexane (Mitsubishi Gas Chemical Co., Ltd. 1,3-BAC active hydrogen equivalent 35.5 g / eq) at room temperature. It was. (Curing agent C) The viscosity of the curing agent C was 10 mPa · s at 20 ° C. After 84 g of epoxy resin B was left in an oven at 40 ° C. for 1 hour (1 hr), 15.5 g of curing agent C was added to epoxy resin B and stirred and mixed at room temperature to obtain a uniform mixture. The viscosity of this mixture was 7000 mPa · s at 30 ° C.
The obtained uniform solution was put into a room temperature defoaming apparatus and defoamed under reduced pressure. After completion of the defoaming operation, the mixture was poured into a flat plate type (260 mm × 200 mm × 3 mm) previously set in a circulation oven at 50 ° C. The flow of the mixture during casting was smooth. After curing at 80 ° C. for 5 hours (hr), the cured product was taken out of the mold. The heat resistance temperature of the obtained cured product was 120 ° C., and the hardness was 84 (Shore D 28 ° C.).

Example 5
55 g of heat-resistant resin A synthesized in Example 1 and 42.4 g of methylhexahydrophthalic anhydride (HN5500, manufactured by Hitachi Chemical Co., Ltd.) were left in an 80 ° C. oven for 1 hour (hr) and then mixed to obtain a uniform mixture. After adding 0.5 g of 2-ethyl-4-merimidazole, the mixture was degassed under heating at 60 to 80 ° C., and poured into a flat plate type (260 mm × 20 mm × 3 mm) that had been placed in a circulating oven at 80 ° C. The flow of the mixture during casting was smooth. After curing at 80 ° C. for 3 hours (hr) and further at 200 ° C. for 2 hours (hr), the cured product was taken out of the mold. The heat-resistant temperature of the obtained cured product was 222 ° C., and the hardness was 86 (Shore D 28 ° C.).

Example 6
55 g of heat-resistant resin A synthesized in Example 1 and 44.8 g of methyl nadic acid (MHAC-P neutralization equivalent 177 g / eq manufactured by Hitachi Chemical Co., Ltd.) were left in an oven at 80 ° C. for 1 hour (hr) and then mixed to obtain a uniform mixture. . After adding 0.5 g of 2-ethyl-4-merimidazole, it was degassed under heating at 60 to 80 ° C., and poured into a flat plate type (260 mm × 20 mm × 3 mm) that had been placed in a circulating oven at 80 ° C. The flow of the mixture during casting was smooth.
After curing at 80 ° C. for 6 hours (hr), the mold was removed from the mold. The cured product was sandwiched between iron plates and further cured at 200 ° C. for 2 hours (hr).
The heat resistance temperature of the obtained cured product was 235 ° C., and the hardness was 86 (Shore D 28 ° C.).

Comparative Example 1
In Example 5, the heat-resistant resin A was replaced with a cresol novolac epoxy resin (Epicron N660, epoxy equivalent 207 g / eq, manufactured by Dainippon Ink and Co., Ltd.), and the amount of methylhexahydrophthalic anhydride (HN5500, manufactured by Hitachi Chemical Co., Ltd.) was adjusted to 42.6 g. The others were performed in the same manner as in Example 5. Since the resin flowability decreased in the latter half of casting, it was warmed with a heat gun to complete casting.
The heat-resistant temperature of the obtained cured product was 208 ° C., and the hardness was 85 (Shore D 28 ° C.).

Comparative Example 2
Example 6 except that 55 g of heat-resistant resin A in Example 6 was replaced with 54 g of cresol novolac epoxy resin (Epiclon N660 manufactured by Dainippon Ink Co., Ltd.) and the amount of methyl nadic acid (MHAC-P manufactured by Hitachi Chemical Co., Ltd.) was changed to 44.2 g. As well as. The heat-resistant temperature of the obtained cured product was 225 ° C., and the hardness was 86 (Shore D 28 ° C.).
Since the resin flowability decreased in the middle of casting, the casting was completed while warming with a heat gun.

Example 7
Heat resistant resin A5, 5 g synthesized in Example 1, and 4.3 g of methylhexahydrophthalic anhydride (HN5500, manufactured by Hitachi Chemical Co., Ltd.) were left in an oven at 80 ° C. for 1 hour (hr), and then taken out and mixed to obtain a uniform mixture. After adding 0.05 g of 2-ethyl-4-merimidazole, the method was removed under heating at 60 to 80 ° C., and the plate was attached to a flat plate type (100 mm × 100 mm × 0.4 mm) set in a circulating oven at 80 ° C. Poured into Funnel. The flow of the mixture at 80 ° C. was smooth, and when observed after 40 minutes, almost all of the resin had flowed into the mold.

Comparative Example 3
The same procedure as in Example 7 was performed except that 5 g of the heat-resistant resin A5 in Example 7 was replaced with a cresol novolac epoxy resin (Epicron N660 manufactured by Dainippon Ink Co., Ltd.). The flowability of the mixture at 80 ° C. was poor, and only about half of the resin flowed in even after 1 hour (hr).

Comparative Example 4
In Example 4, the same procedure was performed except that 84 g of epoxy resin B was changed to 76 g of bisphenol A type liquid epoxy resin (R140 manufactured by Mitsui Chemicals) and 15.5 g of curing agent C was changed to 14.6 g.
The obtained cured product had a heat resistance of 108 ° C. and a hardness of 84 (Shore D 28 ° C.).

Comparative Example 5
Add 245g of bisphenol A type liquid epoxy resin (R140 made by Mitsui Chemicals) to a 500ml round bottom flask with a stirrer and heat to 90 ° C, and cresol novolak epoxy resin (Epicron N660 made by Dainippon Ink Co., Ltd.) 105g in 3 times. A uniform mixture (epoxy resin C) was obtained by adding at a temperature.
3.5 g of 1-cyanoethyl-2-ethyl-4-methylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.) was added to 290 g of methylhexahydrophthalic anhydride (HN5500, manufactured by Hitachi Chemical Co., Ltd.) at room temperature. (Curing agent B) After 50 g of epoxy resin C and 44 g of curing agent B were allowed to stand in a 40 ° C. oven for 1 hour (hr), 43.0 g of curing agent B was added to epoxy resin C and stirred and mixed at room temperature to obtain a uniform mixture.
The obtained uniform solution was put into a room temperature defoaming apparatus and defoamed under reduced pressure. After completion of the defoaming operation, the mixture was poured into a flat plate type (260 mm × 200 mm × 3 mm) previously set in a circulation oven at 50 ° C. The flow of the mixture during casting was smooth. After curing at 80 ° C. for 4 hours (hr) and further at 150 ° C. for 2 hours (hr), the cured product was taken out of the mold. The heat resistance temperature of the obtained cured product was 152 ° C., and the hardness was 84 (Shore D 28 ° C.).

  Table 1 shows the results of the above Examples and Comparative Examples.

  As described above, by using the heat resistant resin A (Example 4), the heat resistance is increased from 108 ° C. to 120 ° C. as compared to Comparative Example 4 in which the heat resistant resin A is not used. Further, Example 7 shows that the heat-resistant resin A has a better flow than the cresol novolac epoxy resin (Comparative Example 3). In addition, Example 5 shows that the heat-resistant resin A has higher heat resistance and better flow than the cresol novolac epoxy resin (Comparative Example 1). In addition, Example 6 shows that the heat-resistant resin A exhibits higher heat resistance and better flow than the cresol novolac epoxy resin (Comparative Example 2). Further, Example 3 shows that the heat-resistant resin A has higher heat resistance than the cresol novolac epoxy resin (Comparative Example 5).

  As described above, 1- [α-methyl-α- (4′-glycidoxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″ -glycidoxyphenyl) ethyl] benzene composition As shown in the examples, gives higher heat resistance and good flowability than the addition of the same amount of conventional heat-resistant material non-borak epoxy resin, and in order to obtain the conventional heat resistance, glycidyl ether of polyfunctional aliphatic alcohol The amount of compound added can be increased to further improve flowability.

a ... length of test piece b ... width of test piece h ... thickness L of test piece ... span F ... load and direction applied by load wedge

Claims (7)

  Epoxy resin 1- [α-methyl-α- (4′-glycidoxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″ -glycidoxyphenyl) ethyl] benzene per 100 parts by weight 0 to 300 parts by weight of a liquid epoxy resin, 0 to 25 parts by weight of a glycidyl ether compound of a polyfunctional aliphatic alcohol, an acid anhydride or amine curing agent as the epoxy resin, the liquid epoxy resin, and the A liquid characterized by containing 0.8 to 1.1 parts by weight of the epoxy group of the glycidyl ether of the functional aliphatic alcohol, and 0.5 to 5 parts by weight of a curing accelerator. Epoxy resin composition.   1- [α-methyl-α- (4′-glycidoxyphenyl) ethyl] -4- [α ′, α′-bis (4 ″ -glycidoxyphenyl) ethyl] benzene is 1- [α-methyl It is obtained by reacting -α (4'-hydroxyphenyl) ethyl] -4- [α ', α'-bis (4 "-hydroxyphenyl) ethyl] benzene and epichlorohydrin. Item 2. The liquid epoxy resin composition according to Item 1.   The liquid epoxy resin composition according to claim 1, wherein the liquid epoxy resin is bisphenol A type diglycidyl ether or bisphenol F type diglycidyl ether.   The liquid epoxy resin composition according to claim 1, wherein the polyglycidyl ether of the polyfunctional aliphatic alcohol is trimethylolpropane triglycidyl ether.   The liquid epoxy resin composition according to claim 1, wherein the acid anhydride curing agent is methylhexahydrophthalic anhydride or methyl nadic anhydride.   The liquid epoxy resin composition according to claim 1, wherein the amine curing agent is 1,3-bisaminomethylcyclohexane.   The curing accelerator is 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, N-benzyl-2-methylimidazole or benzyldimethylamine. Liquid epoxy resin composition.

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