JP3477111B2 - Thermosetting epoxy resin composition - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosetting epoxy resin composition used for adhesives, paints, electric insulating materials, sealants, laminates, and the like. An object of the present invention is to provide a thermosetting epoxy resin composition having excellent mechanical and electrical properties and good workability. [0002] Epoxy resins, polyester resins, phenol resins and the like are well known as thermosetting resins used for electric insulating materials, structural materials and the like. Required, excellent mechanical properties,
There is a need for a resin composition that has electrical characteristics and heat resistance, and that has good workability during curing. Many studies have been made to solve such technical problems. For example, a method of blending triglycidyl isocyanurate with an epoxy resin is disclosed in JP-A-54-10355 and JP-A-54-155.
No. 10356 and Japanese Patent Application Laid-Open No. 54-10357. A method for improving mechanical properties and heat resistance by blending triglycidyl isocyanurate with various polymers is disclosed in Japanese Patent Publication No. 58-44095 and Japanese Patent Publication No.
No. 0-19334. [0003] However, triglycidyl isocyanurate has a relatively high melting point (about 110 ° C).
° C) and high crystallinity, resulting in poor compatibility with the epoxy resin, and a workability problem that it is difficult to obtain a uniform mixture with the epoxy resin. In addition, since the reactivity with the epoxy resin curing agent is extremely high, it is difficult to control the curing reaction, and there is a disadvantage that thermal curing proceeds rapidly and a good cured product cannot be obtained. The inventors of the present invention have conducted intensive studies to improve such problems, and as a result, a monoallyldiglycidyl isocyanurate compound has been found to react with an epoxy resin curing agent. To provide a cured product having mild properties and excellent mechanical properties, electrical properties, and heat resistance, and a monoallyl diglycidyl isocyanurate compound having excellent kneading properties and compatibility with an epoxy resin; It has been found that a thermosetting resin composition comprising allyl diglycidyl isocyanurate, an epoxy resin and an epoxy resin curing agent gives a cured product having excellent mechanical properties, electrical properties, and heat resistance. Was. [0005] The monoallyl diglycidyl isocyanurate compound used in the practice of the present invention is represented by the following general formula. [0006] However, in the formula, R ₁ and R ₂ represent a hydrogen atom or a lower alkyl group. Representative examples of these compounds include monoallyl diglycidyl isocyanurate, 1-allyl-
3,5- (2-methylepoxypropyl) isocyanurate, 1- (2-methylpropenyl) -3,5-diglycidyl isocyanurate, 1- (2-methylpropenyl) -3,5- (2-methylepoxy Propyl) isocyanurate and the like. [0008] The typical epoxy resin curing agent suitable for the practice of the present invention is not particularly limited as long as it reacts with the epoxy resin and is cured, but is usually a compound having a phenolic hydroxyl group, an acid anhydride, or an amine. Kind is used. Compounds having a phenolic hydroxyl group include bisphenol, resorcinol, phenol novolak,
And polyhydric phenols such as cresol novolak. The acid anhydride may be any one usually used as a curing agent for an epoxy resin, such as methyltetrahydrophthalic anhydride and methylhexahydrophthalic anhydride, and is not particularly limited. Examples of the amines include aromatic amines such as metaphenylenediamine, di (aminophenyl) methane (commonly called diaminodiphenylmethane) and diaminodiphenylsulfone, and imidazoles such as 2-ethyl-4-methylimidazole. The epoxy resin used in the present invention is not particularly limited as long as it has a plurality of epoxy groups in a molecule, and specific examples thereof include bisphenol A epoxy resin, bisphenol F epoxy resin, cresol novolak. Epoxy resin, phenol novolak epoxy resin, biphenyl epoxy resin, halogenated epoxy resin and the like. In the practice of the present invention, a curing catalyst may be used to accelerate the curing reaction of the epoxy resin. As a curing catalyst, for example, imidazole compounds such as 2-ethyl-4-methylimidazole and 1-cyanoethyl-2-ethyl-4-methylimidazole, and 1,8-
Tertiary amine compounds such as diazabicyclo (5,4,0) undecene-7; organic phosphine compounds such as triphenylphosphine; and organometallic compounds. In the practice of the present invention, if necessary, an amorphous silica, crystalline silica, calcium carbonate, magnesium carbonate, alumina, magnesia, clay, talc, calcium silicate, titanium oxide, glass fiber, etc. A filler can be blended, and particularly when amorphous silica is used, the effect of lowering the linear expansion coefficient of the epoxy cured product is remarkable. The resin composition of the present invention may further comprise, as a reinforcing agent, various polymers such as phenolic resins and unsaturated polyesters; peroxides represented by dicumyl peroxide; and 2,2'-azo. It is also possible to add a polymerization initiator that promotes the polymerization of allyl groups such as bisisobutyronitrile. In the resin composition of the present invention, in addition to the above, various additives usually used for resins, such as a coupling agent, an antifoaming agent, and a pigment, can be used in combination. [0013] In the practice of the present invention, in the case of using a mono allyl diglycidyl isocyanurate compound and an epoxy resin and an epoxy resin curing agent, monoallyl diglycidyl isocyanurate compound 98-2 parts by weight, preferably 80 to 20 parts by weight 2 to 98 parts by weight of an epoxy resin, preferably 20 to 80 parts by weight of an epoxy resin, and 1 to 10 parts by weight, preferably 2 to 4 parts by weight of an amine-based curing agent with respect to 100 parts by weight of these. Parts by weight,
When an acid anhydride curing agent is used, it is desirable to use an equivalent amount of the curing agent. The method for producing the resin composition of the present invention is not particularly limited. However, after a predetermined amount of each component described above is stirred and mixed, kneading or melt kneading is performed using a roll kneader, kneader, extruder or the like. it can. EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, Comparative Examples and Reference Examples, but the present invention is not limited to these. The evaluation methods in these tests are in accordance with the following test standards and conditions. Flexural modulus, flexural strength: ASTM D-790 Glass transition point: TMA method Gel time: JIS C-2105 (hot plate method at 150 ° C.) Volume resistivity: ASTM D-257 Reference Example 1 (Monoallyl diglycidyl isocyanate) Synthesis of Nurate) 1
In a 3 liter 3-neck flask, add epichlorohydrin 55
5.12 g (6.0 mol), monoallyl isocyanurate 50.75 g (0.3 mol), benzyltrimethylammonium bromide 2.4 g (0.0129 mol)
l) was added and reacted at the boiling point of epichlorohydrin (119 ° C.) for 1 hour. After cooling the reaction solution, a 50% aqueous sodium hydroxide solution
g (0.83 mol) was gradually added, and the mixture was reacted for 1 hour. Next, the reaction solution was allowed to stand and separated into an aqueous layer and an oil layer, and then an oil layer in which monoallyldiglycidyl isocyanurate was dissolved was separated. The oil layer is concentrated under reduced pressure,
81.85 g (yield 97.0%) of monoallyldiglycidyl isocyanurate, which is the target product, was obtained. Reference Example 2 Monoallyl diglycidyl isocyanurate (hereinafter referred to as MA-
100 parts by weight of DGIC) and 2 parts by weight of 2-ethyl-4-methylimidazole (manufactured by Shikoku Chemicals, hereinafter abbreviated as 2E4MZ) as an epoxy resin curing agent were added, and the mixture was heated and stirred using a planetary mixer. The mixture was kneaded to obtain an epoxy resin composition. In the above processing, MA-DG
The IC was melted at about 60 ° C., and the workability during kneading was remarkably improved. The resin composition was primary cured at a temperature of 70 ° C. for 110 minutes, and then secondary cured at a temperature of 150 ° C. for 4 hours to prepare an epoxy cured product. The test results for evaluating the physical properties of the cured product are as shown in Table 1, and the mechanical properties were better than those of the bisphenol A type epoxy resin alone (Comparative Example 1), showing high heat resistance. . Example 1 MA-DGIC: 50 parts by weight, bisphenol A type epicoat 828 as a bisphenol type epoxy resin
50 parts by weight (made by Yuka Shell Epoxy) and 2 parts by weight of 2E4MZ as an epoxy resin curing agent were added thereto, followed by stirring and kneading with a planetary mixer to obtain an epoxy resin composition. In this case, triglycidyl isocyanurate is 100% in Epicoat 828, a typical epoxy resin.
While it did not melt when heated to ℃, MA-DGIC had good compatibility and melted at about 50 ℃, significantly improving the workability of kneading. This resin composition was primary cured at a temperature of 70 ° C. for 110 minutes, and then secondary cured at a temperature of 150 ° C. for 4 hours to prepare a cured product. The results of evaluation tests of the physical properties of this cured product are shown in Table 1, and bisphenol A
The mechanical properties were better than those of a single cured epoxy resin (Comparative Example 1). [Example 2 ] MA-DGIC: 30 parts by weight, Epicoat 828: 70
Using the same parts by weight, the same treatment as in Example 1 was performed to prepare an epoxy resin composition to obtain a cured product. The test results for evaluating the physical properties of the cured product are as shown in Table 1, and the mechanical properties were better than those of a single cured product of bisphenol A type epoxy resin (Comparative Example 1). Example 3 MA-DGIC: 80 parts by weight, Epicoat 828: 20
Using the same parts by weight, the same treatment as in Example 1 was performed to prepare an epoxy resin composition to obtain a cured product. The test results for evaluating the physical properties of the cured product are as shown in Table 1, and the mechanical properties were better than those of a single cured product of bisphenol A type epoxy resin (Comparative Example 1). Reference Example 3 MA-DGIC: 100 parts by weight, methylhexahydrophthalic anhydride (manufactured by Shin Nippon Rika, hereinafter MHH) as a curing agent
PA) (116.3 parts by weight), and 2E4MZ: 0.2 part by weight as an epoxy resin curing accelerator,
The mixture was heated, stirred and kneaded with a planetary mixer to obtain an epoxy resin composition. This composition is treated at a temperature of 90 ° C. for 120
For 1 minute, primary curing was performed, and then secondary curing was performed at a temperature of 150 ° C. for 4 hours to prepare a cured product. The test results for evaluating the physical properties of the cured product are as shown in Table 1. The mechanical properties are better than those of the bisphenol A epoxy resin alone (Comparative Example 1). Compared with the cured product with MHHPA (Comparative Example 2), the mechanical properties were good and high heat resistance was exhibited. Example 4 MA-DGIC: 50 parts by weight, Epicoat 828: 50
A cured product was prepared by performing the same treatment as in Reference Example 3 below using 100 parts by weight of MHHPA as a curing agent by weight. In this case, triglycidyl isocyanurate is 100% in Epicoat 828, a typical epoxy resin.
Monoallyl diglycidyl isocyanurate has good compatibility and melts at about 50 ° C.
The workability of kneading was remarkably improved. The test results for evaluating the physical properties of the cured product are as shown in Table 1. The mechanical properties are better than those of the bisphenol A epoxy resin alone (Comparative Example 1). Compared with the cured product with MHHPA (Comparative Example 2), the mechanical properties were good and high heat resistance was exhibited. Comparative Example 1 2 parts by weight of 2E4MZ as an epoxy resin curing agent was added to 100 parts by weight of Epicoat 828, primary curing was performed at a temperature of 70 ° C. for 110 minutes, and then secondary curing was performed at a temperature of 150 ° C. for 4 hours. Curing was performed to prepare a cured product. The test results for evaluating the physical properties of this cured product were as shown in Table 1. Comparative Example 2 100 parts by weight of Epicoat 828 and 86 parts by weight of MHHPA were used as an epoxy resin curing agent, and 2E4MZ was used as an epoxy resin curing accelerator.
0.2 parts by weight were added, primary curing was performed at a temperature of 90 ° C. for 120 minutes, and secondary curing was performed at 150 ° C. for 4 hours to prepare a cured product. The test results for evaluating the physical properties of the cured product are shown in Table 1. Was as shown in FIG. Comparative Example 3 Tridiglycidyl isocyanurate: 30 parts by weight, Epicoat 828: 70 parts by weight as an epoxy resin, 1 part by weight of Aerosil (# 300, Nippon Aerosil Co., Ltd.) and 2 parts by weight of 2E4MZ as an epoxy resin curing agent The resulting mixture was heated, stirred and kneaded with a planetary mixer to prepare an epoxy resin composition.
At this time, triglycidyl isocyanurate does not dissolve,
It was difficult to obtain a uniform resin composition. The obtained resin composition was subjected to primary curing at a temperature of 60 ° C for 120 minutes, and then to secondary curing at a temperature of 150 ° C for 4 hours.
The results of an evaluation test of the physical properties of this cured product are shown in Table 1. When MA-DGIC was used alone, this thermosetting composition was obtained by using MA-DGIC and bisphenol A type epicoat 828 or acid anhydride. Was poorer in compatibility and workability at room temperature than in the case of using. [ Table 1] According to these test results, mixed system cured product of the mono allyl diglycidyl isocyanurate and bisphenol A type epoxy resin, as compared with the cured product of bisphenol A type epoxy resin alone, excellent mechanical properties Is shown. In addition, monoallyl diglycidyl isocyanurate, compared to triglycidyl isocyanurate,
In the combination system with bisphenol A type epoxy resin,
The compatibility with the bisphenol A type epoxy resin is remarkably excellent. According to the present invention, the workability at the time of kneading at room temperature and the workability at the time of thermosetting are good, the mechanical and electrical properties are excellent, and the heat for providing a cured resin having high heat resistance is excellent. A curable resin composition can be provided.

Claims (1)

(57) [Claim 1] Monoallyl diglycidyl as an essential component
Isocyanurate compounds and epoxy resins and epoxies
Thermosetting epoxy resin containing resin curing agent
Fat composition.