KR0124545B1 - Moulding epoxy resin composition - Google Patents

Abstract

Epoxy resin(i) having a good electric insulation and UV registant force consists of i) 10-30% wt.bisphenol-A epoxy resin having two epoxy gps.of equiv.of 5.0-5.3 eq/kg and viscosity of 10,000-15,000 cps ii) 0,6-4 wt. % reactive delute such as diglicidylether compd.having above 10 of carbon number, 50-70 wt. % inorg. filler such as silica, alluminium hydroxide,allumina mica and clay, 6-24 wt. % hardening agent such as acid anhydride, 0.06-1.2 wt. % accelerator, 0.02-1.2 wt. % silane coupling agent, 0.02-0.6 wt. % settling inhibitor , 0.002-0.4 wt. % defoamer and other additives, R = C1-20 alkene, R2 = C1-15 alkyl, allyl, alkyl, H.

Description

Molding epoxy resin composition

The present invention relates to an epoxy resin composition used as an insulating filler in the electrical and electronic field, and more particularly, to improve electrical insulation and UV resistance and workability, and to reduce cracks and shrinkage of the cured product due to internal stress. The present invention relates to an epoxy resin composition usable for medium and large insulators as insulation fillers in the electronic field.

Epoxy resin is a reactive epoxy group As a compound having two or more molecules in one molecule, each of which exhibits unique physical properties when introducing various groups into its basic skeleton structure, there are various methods of denaturing them depending on the use, and also a curing agent, a filler, an antifoaming agent, a diluent, Since various physical properties are also shown by adding additives such as colorants, it is widely used as a material for each field including electric and electronic fields.

In particular, when epoxy resin is used as an insulator, it has been spotlighted as an insulator in electric and electronic fields because it shows excellent adhesive strength, less curing shrinkage, and excellent dimensional stability, moisture resistance, and chemical resistance.

However, as the use range of the electric and electronic fields is expanded and the applications of thermosetting resins are diversified, a resin composition which can generate less cracks and shrinkage by maintaining electrical insulation properties and reducing internal stress of the cured product is reduced. Asked.

Conventional techniques for meeting this need include a method of modifying an epoxy resin with a silicone-based compound or a rubber-based compound as in the case of Japanese Patent Application Laid-Open No. Hei 1-203423, or polyglycols as in Korean Patent No. 88-10056. There is a method of addition or a method of modification by thermoplastic resin.

However, the modification due to silicone is deteriorated in adhesion between the epoxy and the silicone, the modification due to rubber has a problem that the physical properties of the cured product is greatly changed depending on the heat resistance and the curing agent and curing conditions, and the modification by the thermoplastic resin is a mechanical Although the strength is increased, there is a problem of lowering the electrical insulation properties.

An object of the present invention is to solve the above problems to provide an epoxy resin composition that can be used in the mold of the medium and large insulators of the insulation filling that requires reliability in the electric and electronic fields.

That is, the present invention uses the modified epoxy resin prepared by the reaction of the carboxyl group and the hydroxyl group in the molecule of the fatty acid wax containing one or more double bonds with the epoxy group of the epoxy resin as the main resin, and the internal stress according to the flexibility of the cured product. By reducing shrinkage, cracks, and yuv resistance, and also to prevent rapid heat generation to prevent degradation of workability by toxic gas and improve the impregnation to provide an epoxy resin composition showing excellent physical properties as an insulator in the electrical and electronic field The present invention is described in detail below.

As the epoxy resin used in the present invention, bisphenol A epoxy resins having two epoxy groups having an epoxy equivalent of 5.0-5.3 eq / kg and a viscosity of 10,000-15,000 cps are mainly used. For example, GY2600, GY9708 of Ciba-Geigy Company Shell's Epikoto 828, Dow's DER 331, etc. can be used, and it is preferable to select a hydrolyzed chlorine content, which is preferably 10-30wt% of the total weight of the resin composition. .

The modified epoxy resin is a carboxyl group, which is a terminal group of a fatty acid wax containing one or more double bonds, and a hydroxyl group in the molecule reacts with an oxirane group of a basic epoxy resin. An epoxy equivalent of 1.7-2.5eq / kg and a viscosity of 25,000-60,000cps is used. As the modified epoxy resin having two or more, 4-30 wt% of the total weight is preferably used.

Fatty acid waxes which can be used for the preparation of modified epoxy are selected from those in which the terminal having a molecular weight in the range of 200 to 4,000 has a carboxyl structure and contains at least one hydroxyl group in the molecule. For example, stearic acid, palmitic acid, bedeline acid, lauric acid, Oreic acid, hydrogenated castor oil, and the like and derivatives thereof.

In addition, basic epoxy resins that can be used are liquid at room temperature, and include an alicyclic epoxy resin having two or more epoxy groups in a molecule, a bisphenol F epoxy resin, a bisphenol ED epoxy resin, a glycidyl ether epoxy resin, and a polyfunctional epoxy resin. Resin etc. can be used and 5-50 weight part of fatty acid wax is used normally with respect to 100 weight part of basic epoxy resins. Catalysts used in the preparation of the modification include tertiary amine compounds such as Friedel-Craft catalysts such as boron trifluoride, stanic chloride, mercury chloride, aluminum chloride, trimethylamine, triethylamine, tributylamine and tetramethylbutyldiamine. Peroxide systems, such as di-thi-butyl peroxide, hydrogen peroxide, and thi-butyl peroxide, are used.

The detailed structural formula of the modified epoxy resin used in the present invention is as shown in the following [I] formula.

R ₁ : alkene containing 1 or more double bonds (1-20 carbon atoms)

R ₂ : Contains alkyl, aryl, alkyne or hydrogen having 1-15 carbon atoms.

As a diluent, a reactive diluent having at least one epoxy group and having an epoxy equivalent in the range of 2.5-5.0 eq / kg and having at least 10 carbon atoms is suitable. The reactive diluents include butylglycidyl ether, olefin oxide, phenylglycidyl ether, allyl glycidyl ether, difunctional glycidyl ether, etc., and are used within the range of 0.6-4 wt%. When more than the above limited range, the electrical mechanical and chemical properties of the cured product are lowered, so the content should be adjusted to suit physical properties, and it is preferable to use a multifunctional diluent except for the purpose of lowering the viscosity.

In the resin composition of the present invention, an inorganic filler is blended for improving the mechanical and electrical properties of the cured product. As the inorganic material, silica, aluminum hydroxide, alumina mica, wollastonite, calcium carbonate, clay, and the like may be used. It is controlled at 70wt%, and should be selected carefully considering the particle size distribution and impurity content of the filler according to the use of the product to be molded, the processing method, and the external environment. In addition, the filler is important to improve the mechanical and electrical properties of the epoxy resin composition, the physical properties increase to a certain point depending on the amount of addition and decrease, so it is important to select the appropriate amount and particle size adjusted.

The silica floor used as the filler in the present invention has a particle size distribution of 1 to 15 μm, an oil absorption of 18 to 24%, and a particle size distribution of 1 to 30 μm with respect to 100 parts by weight of the silica floor having a surface area of 1.2 to 1.6 m 2 / gr. In addition, it is possible to mix and use another particle sized silica follower with an oil absorption of 16-18% and a surface area of 0.70-0.90 m 2 / gr at a ratio of 20-100 parts by weight. At this time, the filler is used for drying 0.5-1.5 hours by vibration in a vacuum oven at 80 ℃ before blending, this is to remove moisture or impurities contained in the filler.

As the curing agent, an acid anhydride-based curing agent that can be cured at a high temperature is advantageous, and for example, an alicyclic acid anhydride, methyl tetrahydrophthalic anhydride, hexahydropetalian hydride, methyl hexahydro petalian hydride, or phthalate. There are talic hydride, tetrahydro phthalic hydride and the like, the amount of addition is controlled at 6-24wt%.

In order to suppress heat generation due to rapid viscosity increase, the curing accelerator is advantageous to use a metallic salt system, and the amount of addition is preferably 0.06-1.2 wt%.

The present invention also used a coupling agent such as 3-glyoxy propyltrimethoxysilane 0.02-1.2wt% in order to increase the adhesion between the resin and the filler and improve the mechanical properties, to prevent the settling of the filler, The sedimentation inhibitors, such as bentonic, mica, and talc, were used 0.02-0.6wt%. In addition, silicone oil, fine oil, polyol, terpene polymer, etc. are used to lower the surface tension of the resin to improve static flow and to prevent bubbles from forming on the surface of the resin and to form a smooth surface. A range of 0.002-0.4 wt% is suitable.

In addition, a colorant, a flame retardant, etc. can also be used according to the color of a resin composition, a use use, and a required physical property.

In the present invention, it is possible to use various curing methods, but in order to minimize cracks and shrinkage, it is preferable to gradually increase the curing temperature in steps. For example, 3-4 hours at 90 degrees and 5-6 hours at 125 degrees. After curing for 6-7 hours at 140 degrees, it can be post-cured to obtain the desired cured product.

In the case of using the resin tongue according to the present invention having the composition described above as an insulator, shrinkage and cracking due to internal stress are significantly reduced, and excellent electrical insulation against external environmental changes is generally used in electrical and electronic products. Insulation fill is used in areas where reliability is required.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, and the resin composition was prepared by the conditions of the following (Table 1), and (Reference 1) of the modified epoxy resin used in the Examples and Comparative Examples. A preparation example is shown.

TABLE 1

(Reference 1) Modified epoxy resin preparation

950 g of bisphenol-A epoxy resin having an epoxy equivalent of 5.0-5.3 eq / kg and a viscosity of 10,000-15,000 cps (25 degrees) was added to a round-necked flask, and stirred slowly at 60-80 ° C. for 20 minutes under nitrogen atmosphere, followed by hydrogenation. 93 g of castor oil (melting point 75-85) was added, peroxide and tertiary amine catalyst were added, and a modified epoxy was prepared at a vacuum of 2-5torr, a reaction temperature of 160-250 ° C, and a reaction time of 3-5hr.

(Examples 1-4 and Comparative Examples 5-10)

The composition ratios of the compositions used in the above Examples and Comparative Examples are shown in (Table 2), and the results of the physical property test are shown in (Table 3).

TABLE 2

Evaluation method of hardened | cured material

1) Viscosity of the mixture: measured by Brookfield viscometer at 90 + 5 degrees

2) Port Life: Curing time of cured product 100g at 90 degrees

3) Heat Deflection Temperature (HDT): JIS K-6911

4) Insulation breakdown voltage: JIS K-6911

5) Compressive strength, Charpy impact strength: JIS K-6911

6) Water Absorption: 100 degrees 1 hour Specimen: 60 * 10 * 4mm

As also shown in the above results, when the resin composition according to the present invention (Examples 1 to 4) is out of the scope of the present invention (Comparative Examples 5 to 10), the impact strength, which is a physical property required by the electrical and electronic component material, Compressive strength, dielectric breakdown strength and water absorption have been shown to be excellent, which proves the usefulness of the present invention.

Claims (8)

Molecular weight 400-5000, epoxy equivalent 1.7-2.5eq prepared by transforming a basic epoxy resin which is liquid at room temperature and contains at least two double bonds, at least one double bond, and having a terminal group having a carboxyl group and a fatty acid wax having a hydroxyl group in the molecule. 4-30 wt% of modified epoxy resin having properties of 2kg ~ 60,000cps / kg, 10-30wt% of epoxy resin having 2 epoxy groups having epoxy equivalent of 5.0-5.3eq / kg and 10,000-15,000cps of viscosity, epoxy Reactive diluent 0.6-4wt% which is equivalent to 2.5-5.0 eq / kg and is a diglycidyl ether compound having 10 or more carbon atoms, and fillers such as silica, aluminum hydroxide, alumina mica, wollastonite, calcium carbonate and clay 70wt%, 6-24wt% of acid anhydride hardening agent cured at high temperature, 0.06-1.2wt% of hardening accelerator of metallic salt system, 0.02-1.2wt% of silane coupling agent, 0.02-0.6wt% of anti-settling agent, defoamer 0.002-0.4 wt% and other additions Molding epoxy resin composition, characterized by consisting of a. The epoxy resin composition for molding according to claim 1, wherein the fatty acid wax is selected from stearic acid, palmitic acid, bedelineic acid, lauric acid, oleic acid, hydrogenated castor oil and derivatives thereof. The main epoxy resin according to claim 1, wherein the basic epoxy resin used for the deformation is selected from an alicyclic epoxy resin, a bisphenol F-type epoxy resin, a bisphenol ED-type epoxy resin, a glycidyl ether type epoxy resin, and a polyfunctional epoxy resin. Mold epoxy resin composition. The epoxy resin composition for molding according to claim 1, wherein the reactive diluent is selected from butylglycidyl ether, olefin oxide, phenylglycidyl ether, allyl glycidyl ether, and difunctional nal glycidyl ether. The inorganic filler according to claim 1, wherein the inorganic filler has a particle size distribution of 1-30 μm and an oil absorption of 100 parts by weight of the silica follower having a particle size distribution of 1-5 μm, an oil absorption of 18-24%, and a surface area of 1.2-1.6 m 2 / gr. Fig. 16-18%, epoxy resin composition for casting, characterized in that a mixture of silica floor having a surface area of 0.70-0.90 m 2 / gr at a ratio of 20-300 parts by weight. The method of claim 1, wherein the acid anhydride-based curing agent is selected from methyltetrahydropetalyanide, hexahydropetalyanide, methylhexahydropetalyanide, phthalichydride, tetrahydropetalyanide Epoxy resin composition for casting characterized by the above-mentioned. The method of claim 1, wherein the silane coupling agent is 3-glycithoxypropyltrimethoxysilane, the sedimentation agent is selected from bentonic, mica, talc, the antifoaming agent is selected from silicone oil, fine oil polyol, terpin polymer Epoxy resin composition for casting, characterized in that. The catalyst of claim 1 wherein the catalyst is boron trifluoride, stanic chloride, mercury chloride, aluminum chloride, trimethylamine, triethylamine, tributylamine, tetramethylbutyldiamine, di-thi-butylperoxide, hydrogen peroxide Modified epoxy resin composition, characterized in that selected from thi-butyl peroxide.