JPH10139857A - Silicone-modified epoxy resin, epoxy resin composition and its cured product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject resin having a specific molecular structure and a low melt viscosity, and capable of exhibiting excellent heat resistance and water resistance in the cured product of its composition. SOLUTION: This resin has a structure of formula I [(n) is a mean value and a positive number of 0-5; G is a glycidyl group]. A resin of formula I can be obtained e.g. by reacting a compound of formula II with epichlorohydrin in the presence of an alkali metal hydroxide. Further, a composition containing the resin is obtained by compounding an epoxy resin of formula I with a hardener, a hardening accelerator and an inorganic filler as components. A cured product obtained from the resin or the composition is excellent in heat resistance and water resistance, and useful as a sealing agent, a laminating board, an insulating material, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin, an epoxy resin composition and a cured product thereof having a low melt viscosity and excellent heat resistance and water resistance.

[0002]

2. Description of the Related Art Epoxy resins are generally cured with various curing agents to form cured products having excellent mechanical properties, water resistance, chemical resistance, heat resistance, and electrical properties. It is used in a wide range of fields, such as laminates, molding materials, and casting materials. Conventionally, there is a liquid and solid bisphenol A type epoxy resin obtained by reacting bisphenol A with epichlorohydrin as the epoxy resin most used industrially. Other liquid bisphenol A type epoxy resin is added to tetrabromobisphenol
A flame-retardant solid epoxy resin obtained by reacting the resin A is used industrially as a general-purpose epoxy resin. In recent years, for use in semiconductor encapsulants, tetramethylbiphenol type epoxy resins which are crystalline and have a very low viscosity when melted have attracted attention as being capable of being filled with a high filler and having excellent solder crack resistance.

[0003]

The above-mentioned crystalline epoxy resin has a low melt viscosity, but has heat resistance,
In terms of water resistance, o-
Compared with the cresol novolak type epoxy resin, it is insufficient and a problem is pointed out in terms of long-term reliability.

[0004]

In view of these circumstances, the present inventors have found that an epoxy resin having a specific molecular structure has a low melt viscosity, and that a cured product of the composition has excellent heat resistance and water resistance. The present inventors have found that they have completed the present invention.

That is, the present invention relates to (1) Formula (1)

[0006]

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(In the formula (1), n is an average value, represents a positive number of 0 to 5, and G represents a glycidyl group.)

(2) (a) an epoxy resin composition described above in (1), (b) an epoxy resin composition containing a curing agent, and (3) an epoxy resin composition containing a curing accelerator. (4) The epoxy resin composition according to the above (2) or (3), which contains an inorganic filler. (5) Any of the above (2), (3) and (4) Or a cured product obtained by curing the epoxy resin composition according to item 1.

The compound represented by the formula (1) is, for example, a compound represented by the formula (2)

[0010]

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The reaction of the compound represented by the formula with epihalohydrin can be carried out in the presence of an alkali metal hydroxide.

As a method for obtaining the epoxy compound of the present invention from the compound represented by the formula (2), a known method can be adopted. For example, an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide is added to a dissolved mixture of the compound represented by the formula (2) and an excess epihalohydrin such as epichlorohydrin or epibromhydrin, or
The epoxy resin of the present invention can be obtained by reacting at 0 to 120 ° C. for 0.5 to 10 hours.

In the reaction for obtaining the epoxy resin of the present invention, an aqueous solution of the alkali metal hydroxide may be used. In such a case, the aqueous solution of the alkali metal hydroxide is continuously added to the reaction system. A method may be employed in which water and epihalohydrin are continuously flowed out under reduced pressure or normal pressure, liquids are separated, water is removed, and epihalohydrin is continuously returned into the reaction system.

A quaternary ammonium salt such as tetramethylammonium chloride, tetramethylammonium bromide or trimethylammonium chloride is added to a dissolved mixture of the compound represented by the formula (2) and epihalohydrin as a catalyst. A solid or aqueous solution of an alkali metal hydroxide is added to the halohydrin etherified product of the compound of the formula (2) obtained by reacting for 0.5 to 5 hours, and the reaction is performed again at 20 to 120 ° C. for 0.5 to 10 hours. A method of dehalogenating (ring closing) may be used.

The amount of epihalohydrin used in these reactions is usually 1 to 20 mol, preferably 2 to 10 mol, per equivalent of the hydroxyl group of the compound represented by the formula (2). The amount of the alkali metal hydroxide used is 0.8 to 1.5 with respect to 1 equivalent of the hydroxyl group in the compound represented by the formula (2).
Mole, preferably 0.9 to 1.1 mole. In order to make the reaction proceed smoothly, it is preferable to add an aprotic polar solvent such as dimethyl sulfone and dimethyl sulfoxide in addition to alcohols such as methanol, ethanol and isopropanol to carry out the reaction.

When alcohols are used, they are used in an amount of 2 to 50% by weight, more preferably 4 to 40% by weight, based on the amount of epihalohydrin. When an aprotic polar solvent is used, the amount is 5 to 1 with respect to the amount of epihalohydrin.
It is 50% by weight, more preferably 10 to 140% by weight.

After the reaction product of the epoxidation reaction is washed with water or without washing, the mixture is heated to 100 to 150 ° C. under reduced pressure.
At a pressure of 10 mmHg or less, epihalohydrin and aprotic polar solvent are removed. In order to further reduce the amount of hydrolyzable halogenated epoxy compound, the recovered epoxy resin is dissolved again in a solvent such as toluene, methyl isobutyl ketone, methyl ethyl ketone, and an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide. An aqueous solution can be added for further reaction to ensure ring closure. In this case, the amount of the alkali metal hydroxide used is usually 0.01 to 0.3 mol, preferably 0.05 to 1 equivalent of the hydroxyl group of the compound of the formula (2) used for the epoxidation.
０．２0.2 mol. The reaction temperature is 50 to 120 ° C, and the reaction time is usually 0.5 to 2 hours.

After completion of the reaction, the formed salt is removed by filtration, washing with water, and the like, and the solvent such as toluene, methyl isobutyl ketone and methyl ethyl ketone is distilled off under reduced pressure under heating to obtain the epoxy resin of the present invention.

Hereinafter, the epoxy resin composition of the present invention will be described. In the epoxy resin composition of the present invention, the epoxy resin of the present invention can be used in combination with another epoxy resin. When used together, the proportion of the epoxy resin of the present invention in the total epoxy resin is preferably at least 30% by weight, particularly preferably at least 40% by weight.

Specific examples of other epoxy resins that can be used in combination with the epoxy resin of the present invention include novolak epoxy resins, bisphenol A epoxy resins, bisphenol F epoxy resins, and biphenyl epoxy resins. These may be used alone or in combination of two or more.

The curing agent used in the epoxy resin composition of the present invention includes, for example, amine compounds, acid anhydride compounds, amide compounds, phenol compounds and the like. Specific examples of the curing agent that can be used include diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, dicyandiamide, a polyamide resin synthesized from a dimer of linolenic acid and ethylenediamine, phthalic anhydride, and trianhydride. Melitic acid, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride,
Methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, phenol novolak, and modified products thereof, imidazole, BF ₃ -amine complex, guanidine derivative and the like. It is not limited to these. These may be used alone or in combination of two or more.

The amount of the curing agent used in the epoxy resin composition of the present invention is preferably from 0.7 to 1.2 equivalents to 1 equivalent of the epoxy group of the epoxy resin. If the amount is less than 0.7 equivalents or more than 1.2 equivalents with respect to 1 equivalent of epoxy group, curing may be incomplete and good cured physical properties may not be obtained.

When the above curing agent is used, a curing accelerator may be used in combination. Specific examples of the curing accelerator that can be used include imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2- (dimethylaminomethyl) phenol, and 1,8-diaza. Tertiary amines such as -bicyclo (5,4,0) undecene-7; phosphines such as triphenylphosphine; and metal compounds such as tin octylate. The curing accelerator is used in an amount of 0.1 to 5.0 parts by weight based on 100 parts by weight of the epoxy resin as required.

The epoxy resin composition of the present invention contains an inorganic filler if necessary. Specific examples of the inorganic filler that can be used include silica, alumina, and talc. The inorganic filler is used in the epoxy resin composition of the present invention in an amount of from 0 to 9;
An amount occupying 5% by weight is used. Further, to the epoxy resin composition of the present invention, various compounding agents such as a silane coupling agent, a release agent such as stearic acid, palmitic acid, zinc stearate, and calcium stearate, and a pigment can be added.

The epoxy resin composition of the present invention can be obtained by uniformly mixing the components. The epoxy resin composition of the present invention can be easily made into a cured product by a method similar to a conventionally known method. For example, the epoxy resin of the present invention, a curing agent, and, if necessary, a curing accelerator, an inorganic filler, and a compounding material, if necessary, may be used in an extruder, a kneader, a roller,
The epoxy resin composition is sufficiently mixed until the epoxy resin composition becomes uniform using a tool or the like. The epoxy resin composition is melted and then molded using a casting or transfer molding machine. By heating for 10 to 10 hours, the cured product of the present invention can be obtained.

Further, the epoxy resin composition of the present invention is dissolved in a solvent such as toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, and the like, and is used to prepare glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, paper, etc. A prepreg obtained by impregnating a substrate and drying by heating may be subjected to hot press molding to obtain a cured product. In this case, the solvent is used in an amount of usually 10 to 70% by weight, preferably 15 to 70% by weight, and preferably 15 to 65% by weight in the mixture of the epoxy resin composition of the present invention and the solvent.

Since the epoxy resin of the present invention has a very low melt viscosity and can be filled with a high filler, it can give a cured product having excellent heat resistance and water resistance, and can be used in a wide range of fields. Specifically, it is useful as any electric or electronic material such as a sealing material, a laminate, or an insulating material.
Further, it can be used in the fields of molding materials, adhesives, composite materials, paints, and the like.

[0028]

EXAMPLES Next, the present invention will be described in more detail with reference to Examples and Comparative Examples. Hereinafter, all parts are by weight unless otherwise specified.

Example 1 135 parts of the compound represented by the above formula (2) was added to 370 parts of epichlorohydrin and 92.5 parts of dimethyl sulfoxide while purging with nitrogen gas a flask equipped with a thermometer, a dropping funnel, a condenser, and a stirrer. Was dissolved. 5 more
Heat to 5 ° C and add 40 parts of flaky sodium hydroxide to 10
Add in portions over 0 minutes, then at 55 ° C. for 2 hours,
The reaction was performed at 70 ° C. for 30 minutes. After completion of the reaction, excess epichlorohydrin, dimethyl sulfoxide and the like were distilled off under heating and reduced pressure at 130 ° C. using a rotary evaporator, and 191 parts of methyl isobutyl ketone was added to the residue and dissolved.

Further, this solution of methyl isobutyl ketone was heated to 70 ° C., and a 30% by weight aqueous sodium hydroxide solution 1 was added.
After adding 0 parts and reacting for 1 hour, washing with water was repeated until the pH of the washing solution became neutral. Further, the water layer is separated and removed,
Using a rotary evaporator, methyl isobutyl ketone was distilled off from the oil layer under heating and reduced pressure to obtain 164 parts of the epoxy resin (A) of the present invention represented by the above formula (1). The obtained epoxy resin is a crystal having a melting point of 115 ° C., an epoxy equivalent of 201 g / eq, and n = 0.0 in the formula (1).
It was 6.

Example 2, Comparative Example 1 The epoxy resin (A) obtained in Example 1 as Example 2
The following formula (3) was used as Comparative Example 1.

[0032]

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(Where n = 0.13 (average value) and G
Represents a glycidyl group. ), A crystalline epoxy resin YX-4000H (manufactured by Yuka Shell Epoxy Co., Ltd., epoxy equivalent 196 g / eq, melting point 105 ° C.), and phenol novolak (manufactured by Nippon Kayaku Co., Ltd.) as a curing agent. , Hydroxyl equivalent 106 g / eq, softening point 83 ° C)
And triphenylphosphine (T
Using PP), these were blended in the amounts shown in the column of the composition of the blend in Table 1, roll-kneaded at 70 to 80 ° C for 15 minutes, cooled and pulverized, and the gel time was measured. Further, the pulverized material is further tableted, and a resin molded body is prepared by a transfer molding machine.
Cured at 0 ° C. for 8 hours.

The results of measuring the physical properties of the cured product thus obtained are shown in Table 1 in the column of physical properties of the cured product. The numerical values in the column of the composition of the composition in Table 1 represent parts by weight. Transfer molding conditions Temperature: 150 ° C Molding pressure: 50 kg / cm ² hours: 3 minutes Glass transition temperature Thermomechanical instrument (TMA): TM manufactured by Vacuum Riko Co., Ltd.
-7000 Heating rate 2 ° C / min Water absorption Test piece (cured product): Disk with a diameter of 50 mm and a thickness of 3 mm Weight increase rate (%) after boiling in water at 100 ° C for 24 hours

[0035]

Table 1 Table 1 Example 2 Comparative Example 1 Composition of formulation Epoxy resin (A) 100 YX-4000H 100 Phenol novolak 53 54 TPP 11 1 Physical properties of cured product Glass transition temperature (° C) 142 138 Water absorption (%) 1.2 1.4

Table 1 shows that the cured product of the epoxy resin of the present invention is excellent in heat resistance and water resistance.

[0037]

The epoxy resin of the present invention gives a cured product having excellent heat resistance and water resistance as compared with a crystalline epoxy resin generally used in the past. That is, the epoxy resin of the present invention is a molding material, a casting material, a laminate material, a paint,
It is extremely useful for a wide range of applications such as adhesives and resists.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI (C08K 3/00 3:36 3:22 3:34)

Claims (5)

[Claims] (1) Formula (1) (In the formula (1), n is an average value and represents a positive number from 0 to 5,
G represents a glycidyl group. Epoxy resin represented by). 2. An epoxy resin composition comprising (a) the epoxy resin according to claim 1 and (b) a curing agent. 3. The epoxy resin composition according to claim 2, further comprising a curing accelerator. 4. The epoxy resin composition according to claim 2, further comprising an inorganic filler. 5. A cured product obtained by curing the epoxy resin composition according to any one of claims 2, 3 and 4.