JPH08310986A - Polyphenolic compound, epoxy resin, epoxy resin composition and cured product thereof - Google Patents

Abstract

PURPOSE: To obtain a polyphenolic compound, etc., having specific molecular structure, capable of giving cured products with a combination of high heat resistance, water resistance and mechanical strength, thus useful for molding materials, etc. CONSTITUTION: (A) The objective polyphenolic compound is expressed by formula I ((n) is 1-3; P and R are each H, a halogen, 1-8C alkyl or aryl), and (B) the second objective epoxy resin of formula II (G is glycidyl) is obtained by epoxidizing the component A. The component A is obtained, for example, by condensation reaction between a compound of formula III and a phenolic compound of formula IV in the presence of an acid catalyst (e.g. p-toluenesulfonic acid). It is recommended that the component B be obtained by reaction of the component A with an epihalohydrin in the presence of an alkali metal hydroxide (e.g. sodium hydroxide) at 20-120 deg.C for 1-10h.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin curing agent, an epoxy resin and an epoxy resin composition which give a cured product excellent in heat resistance and mechanical strength.

[0002]

2. Description of the Related Art Heretofore, epoxy resin compositions containing an epoxy resin, a phenol novolac resin, and a curing accelerator as main components have been widely used in the fields of electric / electronic parts and IC encapsulants. The high density and high integration of ICs in recent years have required the sealing materials to have high heat resistance and high toughness. In particular, the harsh condition of immersion in a solder bath in high-density mounting of ICs further increases the requirements for high heat resistance and high toughness of cured products.

[0003]

However, in the conventional epoxy resin composition, the cresol novolac type epoxy resin generally used as the epoxy resin has high heat resistance, but has a drawback that it is inferior in toughness.

On the other hand, the phenol novolac resin, which is generally used as a curing agent, is still insufficient in heat resistance and does not give satisfactory results under the above-mentioned conditions which are becoming more and more severe. Therefore, development of a resin having excellent properties such as heat resistance and toughness in the cured product has been awaited.

[0005]

In view of these circumstances, the present inventors have earnestly studied for an epoxy resin which gives a cured product having excellent heat resistance and toughness, and as a result, polyphenols having a specific molecular structure The present invention has been completed by finding that the epoxy resin obtained by epoxidizing the epoxy compound has excellent heat resistance and toughness in the cured product.

That is, the present invention is based on the equation (1)

[0007]

Embedded image

(In the formula (1), n represents an integer of 1 to 3.
P and R each represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group, and P and R may be the same or different from each other. ) Polyphenols represented by

Equation (2) Equation (2)

[0010]

[Chemical 4]

(In the formula (2), n, P and R have the same meanings as in the formula (1) and G represents a glycidyl group), (3) (a) epoxy resin (B) Epoxy resin composition containing polyphenols of formula (1) described in (1) (4) (a) Epoxy resin of formula (2) described in (2) (b) Curing agent An epoxy resin composition containing

(5) (a) Epoxy resin of formula (2) described in (2) above (b) Epoxy resin composition containing a polyphenol of formula (1) described above in (1), (6) ) The epoxy resin composition according to (3), (4) or (5) above, which contains a curing accelerator, (7) the epoxy resin composition according to (3), (4), (5) or (6) above. A cured product obtained by curing a product is provided.

The compound represented by the formula (1) can be represented by, for example, the formula (3)

[0014]

Embedded image

(In the formula (3), n and P have the same meanings as in the formula (1).)

The compound represented by the formula (X)

[0017]

[Chemical 6] (In the formula, R has the same meaning as in formula (1).) It can be obtained by a condensation reaction with a phenol represented by the formula (1) in the presence of an acid catalyst.

The compound represented by the formula (2) can be obtained, for example, by reacting the compound represented by the formula (1) with epihalohydrin in the presence of an alkali metal hydroxide.

As the compound represented by the formula (3), those obtained by any known method can be used.

Here, the phenols are compounds having at least one phenolic hydroxyl group, and specific examples of the phenols represented by the formula (X) that can be used include phenol, cresol, ethylphenol, n-propyl. Various alkylphenol o-, m-, p- such as phenol, isobutylphenol, t-butylphenol, octylphenol, nonylphenol, xylenol, methylbutylphenol, and di-t-butylphenol.
Isomer, or vinylphenol, allylphenol,
Various propenylphenol and ethynylphenol o
Examples include-, m-, p- isomers, cycloalkylphenols such as cyclopentylphenol, cyclohexylphenol, cyclohexylcresol, and substituted phenols such as phenylphenol. These phenols may be used alone or in combination of two or more.

When carrying out the condensation reaction, the amount of the phenols of the formula (X) used is usually 4 to 60 mol, preferably 5 to 50 mol, per 1 mol of the compound represented by the formula (3).

An acid catalyst is usually used in the above condensation reaction. Although various kinds of acid catalysts can be used, hydrochloric acid,
Inorganic or organic acids such as sulfuric acid, p-toluenesulfonic acid and oxalic acid, and Lewis acids such as boron trifluoride, anhydrous aluminum chloride and zinc chloride are preferable, and p-toluenesulfonic acid, sulfuric acid and hydrochloric acid are particularly preferable. When using a gas such as hydrogen chloride that is in a gas state at room temperature, the reaction may be performed while blowing the gas into the reaction mixture. The amount of these acid catalysts used is not particularly limited, but is usually 0.001 to 0.1 mol with respect to 1 mol of the compound represented by the formula (3). At this time, as a co-catalyst, methyl mercaptan, methyl mercaptoacetic acid, n
-Dodecyl mercaptan etc. may be added to the reaction mixture.

The above condensation reaction can be carried out without a solvent or in the presence of an organic solvent. Specific examples of the organic solvent that can be used include toluene, xylene, and methyl isobutyl ketone. The amount of the organic solvent used is usually 50 to 300% by weight, and preferably 100 to 250% by weight, based on the total weight of the raw materials charged. The reaction temperature is usually in the range of 20 to 200 ° C, preferably 25 to 190 ° C. The reaction time is usually 1 to 30 hours and 2 to 20
Time is preferred.

After completion of the reaction, the washing liquid of the product has a pH value of 3 to
Neutralization treatment or water washing treatment is carried out until it shows 7, preferably 5 to 7. When washing with water, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alkaline earth metal hydroxides such as calcium hydroxide and magnesium hydroxide, ammonia, sodium dihydrogen phosphate and diethylenetriamine and trihydrate. Various basic substances such as organic amines such as ethylene tetramine, aniline and phenylenediamine may be used as the neutralizing agent. In the case of washing with water, it may be carried out according to a conventional method. For example, water in which the above-mentioned neutralizing agent is dissolved is added to the reaction product, and the operations of liquid separation and extraction are repeated.

After the neutralization treatment, unreacted phenols and solvent are distilled off under reduced pressure heating to concentrate the product,
The polyphenols of the present invention represented by the formula (1) (hereinafter, simply referred to as polyphenols unless otherwise specified) can be obtained.

As a method for obtaining the epoxy resin of the present invention represented by the formula (2) from polyphenols, a known method can be adopted. For example, sodium hydroxide, potassium hydroxide or another alkali metal hydroxide is added all at once to a dissolved mixture of the obtained polyphenols and excess epichlorohydrin or epihalohydrin such as epibromhydrin, or 20 to 120 ° C. while being added. The epoxy resin of the present invention can be obtained by reacting at the temperature of 1 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 which case an aqueous solution of the alkali metal hydroxide is continuously added to the reaction system. Water and epihalohydrin may be continuously distilled off under reduced pressure or normal pressure, and the liquid may be further separated to remove water and the epihalohydrin may be continuously returned to the reaction system.

Further, a quaternary ammonium salt such as tetramethylammonium chloride, tetramethylammonium bromide and trimethylbenzylammonium chloride is added as a catalyst to a dissolved mixture of polyphenols and epihalohydrin, and the mixture is reacted at 50 to 150 ° C. for 1 to 5 hours. Alternatively, a solid or aqueous solution of an alkali metal hydroxide may be added to the resulting halohydrin etherified product of polyphenols, and the mixture may be reacted again at a temperature of 20 to 120 ° C. for 1 to 10 hours for dehydrohalogenation (ring closure).

The amount of epihalohydrin usually used in these reactions is usually 1 to 20 mol, preferably 2 to 10 mol, based on 1 equivalent of hydroxyl group of polyphenols. The amount of alkali metal hydroxide used is 0.8 to 1.5 mol, preferably 0.9 to 1.1 mol, per equivalent of hydroxyl groups of polyphenols. Further, in order to allow the reaction to proceed smoothly, it is preferable to carry out the reaction by adding an aprotic polar solvent such as dimethyl sulfone or dimethyl sulfoxide in addition to alcohols such as methanol and ethanol.

When alcohols are used, the amount used is usually 2 to 20% by weight, preferably 4 to 15% by weight, based on the amount of epihalohydrin. When an aprotic polar solvent is used, it is usually 5 to 100% by weight, preferably 10 to 90% by weight, based on the amount of epihalohydrin.

After washing these reaction products of the epoxidation reaction with or without washing with water, under heating and reduced pressure, 110 to 250 ° C.,
Epihalohydrin, solvent, etc. are removed at a pressure of 10 mmHg or less. To obtain an epoxy resin having less hydrolyzable halogen, the obtained epoxy resin is dissolved again in a solvent such as toluene or methyl isobutyl ketone, and an aqueous solution of an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide is prepared. Can be added to carry out 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 0.2 mol, relative to 1 equivalent of hydroxyl groups of the polyphenols used for epoxidation. Reaction temperature is usually 50
The reaction time is usually 0.5 to 2 hours.

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

The epoxy resin composition of the present invention can be obtained by using the epoxy resin of the present invention and / or the polyphenols of the present invention as an essential component, and further adding a curing accelerator and the like if necessary. (3), (5),
In the epoxy resin composition of the present invention described in (6), the polyphenols of the present invention can be used alone as the component (b) or in combination with other curing agents. When used in combination, the proportion of the polyphenols of the present invention in the total curing agent is preferably 30% by weight or more, and particularly preferably 40% by weight or more. Specific examples of the curing agent that can be used in combination with the polyphenols of the present invention include diaminodiphenylmethane,
Amine compounds such as diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, dicyandiamide, polyamide resins synthesized from a dimer of linolenic acid and ethylenediamine, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, Maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic acid anhydride,
Examples thereof include novolak resins such as hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, phenol novolac and cresol novolac, and modified products thereof, imidazole, BF ₃ -amine complex, guanidine derivative and the like. These curing agents may be used alone or in combination of two or more.

In the epoxy resin composition of the present invention described in (4), (5) and (6) above, the epoxy resin of the present invention is used alone as the component (a) or in combination with another epoxy resin. You can When used in combination, the proportion of the epoxy resin of the present invention in the total epoxy resin is preferably 30% by weight or more, and particularly preferably 40% by weight or more.
In this case, the epoxy resin used is not particularly limited as long as it is a compound having two or more epoxy groups in one molecule and is generally used for electronic devices. Specific examples of epoxy resins that can be used in combination include phenol novolac type epoxy resins, cresol novolac type epoxy resins, naphthol novolac type epoxy resins and other novolac type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AD type resins. Epoxy resins obtained from aromatic dihydric phenols such as epoxy resins, bisphenol S type epoxy resins, bisphenol I type epoxy resins, biphenyl type epoxy resins, etc. Obtained by reacting polybasic acids such as phthalic acid and dimer acid with epihalohydrin Examples include glycidyl ester type epoxy resins, glycidyl amine type epoxy resins obtained by reacting polyamines such as diaminodiphenylmethane and isocyanuric acid with epihalohydrin. That. These epoxy resins may be used alone or in combination of two or more.

In the epoxy resin composition described in (3) and (6), examples of the epoxy resin as the component (a) include the epoxy resins of the present invention and the other epoxy resins described above. In addition, in the epoxy resin compositions described in (4) and (6), examples of the curing agent as the component (b) include the polyphenols of the present invention and the other curing agents.

In the epoxy resin composition of the present invention, the amount of the curing agent as the component (b) used is preferably 0.7 to 1.2 equivalents relative to 1 equivalent of epoxy groups of the epoxy resin. When the amount is less than 0.7 equivalent based on 1 equivalent of epoxy group,
On the other hand, if the amount exceeds 1.2 equivalents, curing may be incomplete and good cured physical properties may not be obtained.

A curing accelerator may be used in combination in the epoxy resin composition of the present invention. Specific examples of the curing accelerator that can be used include, for example, 2-methylimidazole and 2
-Imidazoles such as -ethylimidazole and 2-ethyl-4-methylimidazole, 2- (dimethylaminomethyl) phenol, 1,8-diaza-bicyclo (5,4,4)
0) Tertiary amines such as undecene-7, phosphines such as triphenylphosphine, and metal compounds such as tin octylate. The curing accelerator may be used in an amount of 0.1 to 5.0 parts by weight based on 100 parts by weight of the epoxy resin.

Further, to the epoxy resin composition of the present invention, various compounding agents such as a filler such as silica, alumina and talc, a silane coupling agent, a release agent and a pigment can be added if necessary. .

The epoxy resin composition of the present invention can be obtained by uniformly mixing the components. The epoxy resin composition of the present invention containing the epoxy resin of the present invention, a curing agent, and optionally a curing accelerator can be easily made into a cured product by the same method as a conventionally known method. For example, an epoxy resin (component (a)) and a curing agent (component (b)), a curing accelerator used as necessary, a filler and other compounding agents are added as required to an extruder, kneader, roll, etc. To obtain an epoxy resin composition by thoroughly mixing until uniform,
The epoxy resin composition is melted and then molded using a casting or transfer molding machine, and further 80 to 200
A cured product can be obtained by heating at 0 ° C. for 2 to 10 hours.

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 to prepare glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, paper and the like. A prepreg obtained by impregnating a base material with heating and drying can be hot-press molded to obtain a cured product. The solvent is used such that the solvent in the mixture of the epoxy resin composition of the present invention and the solvent is usually 10 to 70% by weight, preferably 15 to 65% by weight.

[0041]

EXAMPLES Next, the present invention will be described more specifically by way of Examples and Comparative Examples. In the following, parts are parts by weight unless otherwise specified.

Example 1 A flask equipped with a thermometer, a dropping funnel, a cooling tube, a fractionating tube and a stirrer was charged with the following formula (4).

[0043]

[Chemical 7]

112 parts of the compound represented by: and phenol 9
40 parts were charged, and the mixture was stirred at room temperature while blowing nitrogen. 0.5 parts of p-toluenesulfonic acid (monohydrate) was slowly added while paying attention to heat generation so that the liquid temperature did not exceed 50 ° C. Then, the mixture was heated to 110 ° C. in an oil bath and reacted for 5 hours. In the meantime, 18 ml of the produced water using a fractionating pipe
I pulled it out. After the reaction was completed, 1000 ml of methyl isobutyl ketone was further added, and the mixture was transferred to a separating funnel and washed with water. After washing with water until the washing water becomes neutral, unreacted phenol and solvent are removed from the organic layer under heating and reduced pressure, and the following formula (5)

[0045]

Embedded image

197 parts of the polyphenols (A) of the present invention represented by The obtained polyphenols (A) have a softening point of 93.1 ° C. and a hydroxyl equivalent of 141 g /
It was eq.

Example 2 Polyphenols (A) 141 was added to a flask equipped with a thermometer, a condenser and a stirrer while purging with nitrogen gas.
Parts, 370 parts of epichlorohydrin, and 92.5 parts of dimethyl sulfoxide were charged and dissolved. The mixture was further heated to 45 ° C., 40.4 parts of flaky sodium hydroxide (purity 99%) was added portionwise over 90 minutes, and then the mixture was further reacted at 45 ° C. for 2 hours and at 70 ° C. for 1 hour. After the reaction, 130 ℃
Then, dimethylsulfoxide and epichlorohydrin were distilled off under heating and reduced pressure, and 400 parts of methyl isobutyl ketone was added to the residue and dissolved.

Further, this methyl isobutyl ketone solution was heated to 70 ° C. to prepare a 30% by weight sodium hydroxide aqueous solution 1
After adding 0 part and reacting for 1 hour, washing with water was repeated 3 times to make the pH of the washing solution neutral. Further, the water layer is separated and removed, and methyl isobutyl ketone is distilled off from the oil layer under heating and reduced pressure by using a rotary evaporator to obtain the following formula (6).

[0049]

[Chemical 9]

179 parts of the epoxy resin (B) of the present invention represented by the formula (G represents a glycidyl group) were obtained. The obtained epoxy resin had a softening point of 78.5 ° C. and an epoxy equivalent of 217 g / eq.

Example 3 Instead of the compound represented by the above formula (4), the following formula (7)

[0052]

[Chemical 10]

The reaction was performed in the same manner as in Example 1 except that 119 parts of the compound combined in (1) was used and 1080 parts of o-cresol was used instead of phenol, and the following formula (8) was used.

[0054]

[Chemical 11]

218 parts of the polyphenols (C) of the present invention represented by The obtained polyphenols (C) had a hydroxyl group equivalent of 159 g / eq and a softening point of 96.
It was 3 ° C.

Example 4 An epoxidation reaction was carried out in the same manner as in Example 2 except that 159 parts of polyphenol (C) was used, and the following formula (9) was used.

[0057]

[Chemical 12]

221 parts of the epoxy resin (D) of the present invention represented by the formula (wherein G represents a glycidyl group) was obtained. The obtained epoxy resin had a softening point of 80.3 ° C. and an epoxy equivalent of 236 g / eq.

Examples 5 and 6 Orthocresol novolac type epoxy resin EOCN1
020 (epoxy equivalent 200 g / eq, manufactured by Nippon Kayaku Co., Ltd.) obtained polyphenols (A) and (C), using triphenylphosphine (TPP) as a curing accelerator,
Formulated in the composition column of the composition of Table 1 at 70 ° C
Kneading with a roll for 15 minutes at 150 ℃, molding pressure 50kg
/ Cm ² 180 seconds to transfer molding, the 2 hours then 160 ° C., further creates a test piece allowed to cure for eight hours at 180 ° C., was measured glass transition point, the flexural strength.
The results are shown in Table 1. The conditions for measuring the glass transition point and the bending strength are as follows. Further, in the table, the numerical values in the column of formulation composition indicate parts by weight.

Glass transition temperature thermomechanical measuring device (TMA): manufactured by Vacuum Riko Co., Ltd. TM-7000 Temperature rising rate: 2 ° C./min Bending strength According to JIS K-6911

[0061]

[Table 1] Table 5 Example 5 Example 6 Composition of formulation EOCN1020 100 100 Polyphenols (A) 71 Polyphenols (C) 80 TPP 1 1 Physical properties of cured product Glass transition point (° C) 166 164 Flexural strength (Kg) / mm ² ) 11.5 11.8

Examples 7 and 8 Phenol novolac (softening point 83 ° C., hydroxyl equivalent 106 g / g) as a curing agent for epoxy resins (B) and (D)
eq), triphenylphosphine (T
PP) and compounded in the composition shown in the column of composition of Table 2 and kneaded by a roll at 70 ° C. for 15 minutes, and transfer molded at 150 ° C. at a molding pressure of 50 kg / cm ² for 180 seconds. A test piece was prepared by curing at 160 ° C. for 2 hours and further at 180 ° C. for 8 hours, and the glass transition point and bending strength were measured. Table 2 shows the results. The glass transition point,
Bending strength measurement conditions are as described above. Further, in the table, the numerical value in the column of composition of formulation shows parts by weight.

[0063]

Table 2 Table 2 Example 7 Example 8 Composition of compound Epoxy resin (B) 100 Epoxy resin (D) 100 Phenol novolac 51 48 Physical properties of cured product TPP 11 Glass transition point (° C) 172 170 Bending strength ( Kg / mm ² ) 11.9 12.1

Examples 9 and 10 Polyphenols (C) as curing agents for epoxy resin (B), polyphenols (A) as curing agent for epoxy resin (D), triphenylphosphine (TPP) as curing accelerator Blended with the composition shown in the column of the composition of the blend in Table 3 and kneaded with a roll at 70 ° C. for 15 minutes,
Transfer molding is performed at 150 ° C. and a molding pressure of 50 kg / cm ² for 180 seconds, and then at 160 ° C. for 2 hours, and further 1 hour.
A test piece was prepared by curing at 80 ° C. for 8 hours, and the glass transition point and bending strength were measured. The results are shown in Table 3. The conditions for measuring the glass transition point and the bending strength are as described above. In addition, in the table, the numerical values in the column of composition of formulation represent parts by weight.

[0065]

Table 3 Table 9 Example 9 Example 10 Composition of the compound Epoxy resin (B) 100 Polyphenols (C) 73 Epoxy resin (D) 100 Polyphenols (A) 60 TPP 1 1 Physical properties of cured product Glass transition point (℃) 181 179 Bending strength (Kg / mm ² ) 12.2 12.5

From Tables 1 to 3, cured products of the epoxy resin of the present invention and the polyphenols of the present invention have a high glass transition point,
And high mechanical strength.

[0067]

INDUSTRIAL APPLICABILITY The epoxy resin or polyphenols of the present invention can give a cured product having excellent heat resistance, water resistance and mechanical strength, and can be used as a molding material, casting material, laminating material, insulating material, It is extremely useful for a wide range of applications such as composite materials, paints, adhesives and resists.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H01L 23/29 H01L 23/30 R 23/31

Claims (7)

[Claims] 1. A formula (1): (In the formula (1), n represents an integer of 1 to 3. P and R each represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms or an aryl group, and P and R are the same as each other. Or may be different). 2. Formula (2): (In formula (2), n, P, and R have the same meanings as in formula (1), and G represents a glycidyl group). 3. An epoxy resin composition comprising: (a) an epoxy resin; (b) a polyphenol of the formula (1) according to claim 1. 4. An epoxy resin composition comprising (a) an epoxy resin of the formula (2) according to claim 2 and (b) a curing agent. 5. An epoxy resin composition comprising (a) an epoxy resin of formula (2) according to claim 2 and (b) a polyphenol of formula (1) according to claim 1. 6. The epoxy resin composition according to claim 3, 4 or 5 containing a curing accelerator. 7. A cured product obtained by curing the epoxy resin composition according to claim 3, 4, 5, or 6.