JPH0480930B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for producing an epoxide.

More specifically, the present invention relates to a method for producing epoxides particularly useful as materials for electrical and electronic components.

In recent years, resin encapsulation has become mainstream in materials for electrical and electronic components, especially semiconductor encapsulation materials, instead of conventional ceramics from the standpoint of mass production and cost. Novolac-type epoxy resins are mainly used as sealing resins due to their excellent heat resistance and water resistance, but halogens (especially hydrolyzable halogens) cause a decrease in electrical characteristics as the degree of integration increases.
The emergence of high quality resins with low content is strongly desired.

The conventionally known method for producing novolac type epoxy resin involves reacting a phenolic novolac resin with epihalohydrin, and although it contains almost no inorganic halogen through post-treatment,
1000ppm of organic halogens that decompose under high temperature and high humidity
It contained some amount. Novolak-type epoxy resins containing such organic halogens cannot be used as easy separation methods such as distillation, which are used for monomers, and are not suitable as sealing materials for high integration due to the high halogen concentration they contain. The drawback was that it could not be used.

The present inventors focused on epoxidation by oxidation of olefin as an epoxidation method that does not use epihalohydrin, and as a result of intensive research, the allyl ether compound was combined with at least one of a quaternary ammonium salt, a vanadium compound, a tungsten compound, and a molybdenum compound. and a phosphorus compound as a catalyst to react with hydrogen peroxide in a two-phase system in the presence of an organic solvent, thereby completing the present invention by discovering that the desired epoxidized product can be industrially advantageously produced without the above-mentioned problems. I came to the conclusion.

According to this method, an allyl ether compound is dissolved in an organic phase and reacted with an aqueous phase containing hydrogen peroxide in a two-phase system. As a result, the desired epoxide compound is obtained in the organic phase, and an excess of Since hydrogen oxide and the catalyst remain in the aqueous phase, they can be easily separated by washing with water and separating the liquids after the reaction is completed.

However, when extracting the desired epoxidized product by concentrating the organic phase, if a highly water-soluble quaternary ammonium salt is used as one of the catalysts, it can be removed by the water washing and separation described above. Since those with low water solubility remain in the organic phase together with epoxides, when high temperature concentration is performed, the generated epoxy groups undergo ring-opening polymerization and gel, increasing the epoxy equivalent. It remains and causes a decline in performance as a semiconductor packaging material.

Therefore, the inventors of the present invention further investigated and conducted intensive research on a method to concentrate and extract high-quality epoxy compounds without causing deterioration of the epoxide compound.As a result, they conducted an epoxidation reaction, washed with water, and separated the liquids. It is possible to remove the quaternary ammonium salt by distilling off most of the solvent from the organic phase at a low temperature and then washing with alcohol. They discovered that there is no such thing and completed the present invention.

That is, the present invention provides the following general formula (), (In the formula, n is a number from 2 to 20, and R ₁ , R ² R ₃ and R ₄ may be the same or different and each represents hydrogen or a methyl group.) is reacted in a two-phase system in the presence of an organic solvent using hydrogen peroxide as an oxidizing agent, at least one of a quaternary ammonium salt, a vanadium compound, a tungsten compound and a molybdenum compound, and a phosphorus compound as a catalyst. The following general formula (), (wherein, n, R ₁ , R ₂ , R ₃ and R ₄ have the same meanings as above).

Furthermore, the present invention uses an allyl etherified product represented by the general formula () using hydrogen peroxide as an oxidizing agent, a quaternary ammonium salt and a vanadium compound as a catalyst, at least one of a tungsten compound and a molybdenum compound, and a phosphorus compound, The above general formula is characterized in that the reaction is carried out in a two-phase system in the presence of an organic solvent, then washed with water, separated, the organic phase is concentrated at a low temperature, most of the organic solvent is distilled off, and then washed with an alcohol. A method for producing an epoxide represented by () is provided.

According to the method of the present invention, a high quality epoxidized product with a low organic halogen content can be industrially advantageously produced. The present invention will be explained in detail below.

Specific examples of allyl ether compounds used as raw materials include bisphenol A diallyl ether, bisphenol F diallyl ether, allyl etherified phenol novolak resin, allyl etherified cresol novolak resin, and allyl etherified phenol cresol cocondensation novolak resin. The resin is exemplified by allyl etherified cresol xylenol cocondensation novolak resin. In view of the purpose of the present invention, these materials preferably have a low halogen content, and can be synthesized, for example, by the method described in Japanese Patent Application No. 103039/1982. Among these, allyl etherified novolac resins are preferably used.

The hydrogen peroxide used in the present invention is generally an aqueous solution having a hydrogen peroxide content of 10 to 80%, and may be used in an amount of 1 equivalent or more based on the allyl group.

The quaternary ammonium salts used in the present invention include trioctylmethylammonium salt, cetyldimethylbenzylammonium salt, dicetyldimethylammonium salt, N-laurylpyridinium salt, N-laurylpicolinium salt, N-benzylpyridinium salt, N-benzylpicolinium salt and the like can be mentioned. Among these, trioctylmethylammonium salt, cetyldimethylbenzylammonium salt, and N-laurylpyridinium or picolinium salt are preferred, and trioctylmethylammonium salt is particularly preferably used.

As a counter ion for quaternary ammonium,
Examples include NO ₃ ⁻ , OH ⁻ , HSO ₄ ⁻ , H ₂ PO ₄ ⁻ , HWO ₄ ⁻ and the like.

The amount of the quaternary ammonium salt used is 0.001 to 0.5 weight ratio to the allyl ether compound.

Vanadium compounds, tungsten compounds, and molybdenum compounds include vanadic acid, tungstic acid, and molybdic acid, and their corresponding neutral or acid salts of alkali metals and alkaline earth metals, metal carbonyls, oxides, sulfides, These include naphthenates, stearates, etc. Among these, tungsten compounds, particularly alkali metal salts of tungstic acid, are preferred. The amount used is 0.0005 to 0.5 weight ratio of vanadium, tungsten and molybdenum to the allyl etherified product.

Examples of phosphorus compounds include phosphoric acid, phosphorous acid, polyphosphoric acid, pyrophosphoric acid and oxides such as P ₂ O ₅ P ₂ O ₃
etc., with phosphoric acid being particularly preferred. The amount used is 0.0005 as phosphorus for allyl ether compound.
~0.5 weight ratio.

These catalysts have little catalytic effect on the epoxidation reaction below the above-mentioned usage range, and even if they are used beyond that range, it cannot be said to be industrially advantageous.

The effect of these catalysts is that phosphorus compounds promote the reaction of vanadium compounds, tungsten compounds, and molybdenum compounds with hydrogen peroxide to become pervanadium compounds, pertungsten compounds, and permolybdenum compounds, respectively, and pervanadium compounds , pertungsten compounds and permolybdenum compounds promote epoxidation of allyl groups,
It is believed that the quaternary ammonium salt is for transferring pervanadium compounds, pertungsten compounds, and permolybdenum compounds from the aqueous phase to the organic phase.

The organic solvent used in the present invention may be any organic solvent as long as it is stable under the reaction conditions, is liquid at room temperature, separates from water, and dissolves the allyl ether compound and the epoxide compound.

Examples include aromatic hydrocarbons such as benzene, toluene, and xylene; halogenated hydrocarbons such as chloroform, 1,2-dichloroethane, and chlorobenzene; ketones such as methyl isobutyl ketone and methyl ethyl ketone; butyl acetate, ethyl acetate, and propion. esters of carboxylic acids such as ethyl acid;
Mention may be made of nitro compounds such as nitromethane and nitrobenzene. Among these, aromatic hydrocarbons are preferred.

The epoxidation reaction of the present invention is usually carried out at a temperature of 20 to 100°C, preferably 30 to 80°C. The reaction rate is extremely slow at temperatures below 20°C, and although the reaction can be carried out at temperatures above 100°C, it requires a pressurizing device and is not particularly advantageous industrially.

Washing with water after the epoxidation reaction can be carried out at room temperature to 100°C. In order to improve the liquid separation properties after washing with water, a solvent can be further added to dilute the solution after the reaction.

It is best to distill off the solvent after epoxidation at a low temperature to suppress ring-opening polymerization of the epoxy group.
If the temperature is too low, a large amount of solvent will remain in the epoxy resin, so the temperature should be between room temperature and 100°C, preferably
It is best to do this at a temperature of 40° to 80°C.

The alcohol used for cleaning may be one that is liquid at room temperature, has low solubility for epoxides, and dissolves quaternary ammonium salts well.
Examples include methanol, ethanol, iso-propyl alcohol, n-propyl alcohol, n-propyl alcohol,
-butyl alcohol, iso-butyl alcohol,
Examples include benzyl alcohol and cyclohexyl alcohol.

The amount of alcohol used is 0.5 to 50 weight ratio, preferably 1 to 10 weight ratio, based on the epoxidized product. If the amount of alcohol used is less than the above range, the whole will become a viscous liquid when cooled after cleaning, and the removal effect of quaternary ammonium salts will be small.
If a large amount of alcohol is used, a small amount of the epoxidized product will be dissolved in the alcohol, resulting in large losses, which is not preferred from an industrial standpoint.

The washing is carried out at room temperature to 100°C, preferably around the softening point of the epoxide. That is, when the temperature is low, the cleaning effect is low, and when the temperature is high, ring opening of the epoxy group is caused. The cleaning time may be several minutes or more, and the cleaning may be performed once to several times.

After washing with alcohol, the mixture may be cooled to room temperature or lower, the alcohol phase may be separated, and the mixture may be directly concentrated, but it is more preferable to redissolve the epoxidized product after washing in a solvent, wash with water, and then concentrate.
In this case, high concentration at 100°C or higher is possible, and a high quality epoxide can be obtained.

EXAMPLES The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited thereto. Note that in the examples, parts represent weight units.

Example 1 50 parts of allyl etherified cresol novolak resin with a Cl content of 20 ppm and 2 parts of trioctylmethylammonium hydrosulfate were dissolved in 50 parts of toluene and placed in a 4-necked flask equipped with a stirrer, condenser, and thermometer. I prepared it. To this was added 3.5 parts of sodium tungstate dihydrate and 1.5 parts of 85% phosphoric acid dissolved in 10 parts of water, and the temperature was raised to 60°C. After raising the temperature, 20.5 parts of 66 w/v% hydrogen peroxide was added dropwise with stirring, and then an epoxidation reaction was carried out at 60°C for 14 hours.

After the reaction was completed, 60 parts of toluene and 250 parts of water were added to perform water washing and separation. After separation, most of the toluene is
Distill at 40℃, add 120 parts of methanol and boil at 60℃ for 20 minutes.
It was kept warm for minutes. This was cooled, the methanol phase was removed, 120 parts of methanol was added again, and the mixture was kept at 60°C for 20 minutes. After cooling, the methanol phase was removed and the precipitate was
The mixture was dissolved in 120 parts of methyl isobutyl ketone, washed with water, etc., and then concentrated under reduced pressure at 5 mmHg and 150°C to obtain 40 parts of a pale yellow semi-solid resin. This resin has an epoxy equivalent of 222g/eq and a total chlorine content.
It was 30ppm.

Example 2 10 parts of allyl etherified cresol novolak resin with a Cl content of 20 ppm and 0.6 parts of trioctylmethylammonium hydroxide were dissolved in 10 parts of toluene and charged into a 4-necked flask equipped with a stirrer, condenser, and thermometer. . To this, add 0.7 parts of sodium tungstate dihydrate and 0.4 parts of 85% phosphoric acid to 2 parts of water.
The solution was added to the solution and the temperature was raised to 70°C. After raising the temperature, 4.1 parts of 69% hydrogen peroxide solution was added dropwise while stirring, and an epoxidation reaction was carried out at 70°C for 8 hours. After the reaction was completed, 12.1 parts of toluene and 50 parts of water were added to perform water washing and liquid separation. After separation, toluene was distilled off at 50°C, 24 parts of methanol was added, and the mixture was washed at 65°C for 20 minutes. Cool this, remove the methanol phase, and methanol again.
24 parts were added and kept at 65°C for 20 minutes. After cooling, remove the methanol phase and convert the precipitate to methyl isobutyl ketone.
After dissolving in 24 parts and processing such as washing with water,
Concentrate under reduced pressure at mmHg 150℃, epoxy equivalent 244g/
eq, 7.2 parts of a pale yellow semi-solid resin with a total chlorine content of 25 ppm was obtained.

Example 3 In the same manner as in Example 1, isopropanol was added to the concentrate that had been subjected to reaction, water washing, liquid separation, and solvent distillation.
It was kept warm at 70°C for 20 minutes.

After cooling, the isopropanol phase was removed, isopropanol was added again, and the mixture was kept at 70°C for 20 minutes. After cooling, the isopropanol phase was removed, the precipitate was dissolved in toluene, washed with water, etc.
Concentrate under reduced pressure at Hg 150℃, epoxy equivalent: 241g/
A light brown semi-solid resin of eq was obtained.

Comparative Example The toluene phase, which had been reacted, washed with water, and separated in the same manner as in Example 1, was directly concentrated under reduced pressure at 5 mmHg and 150°C to obtain a brown gelled product. This product was insoluble in dioxane for measuring epoxy equivalent.

Claims (1)

[Claims] 1. General formula _{Allyl represented by _} The etherified product is reacted in a two-phase system in the presence of an organic solvent using hydrogen peroxide as an oxidizing agent and at least one of a quaternary ammonium salt, a vanadium compound, a tungsten compound, a molybdenum compound, and a phosphorus compound as a catalyst. A general formula characterized by (In the formula, n, R ₁ , R ₂ , R ₃ and R ₄ have the same meanings as above.) A method for producing an epoxide compound represented by the following. 2 general formula _{Allyl represented by _} The etherified product is reacted in a two-phase system in the presence of an organic solvent using hydrogen peroxide as an oxidizing agent and at least one of a quaternary ammonium salt, a vanadium compound, a tungsten compound, a molybdenum compound, and a phosphorus compound as a catalyst. After washing with water and separating the layers, the organic phase is concentrated at a low temperature to remove most of the organic solvent, and then washed with an alcohol. (In the formula, n, R ₁ , R ₂ , R ₃ and R ₄ have the same meanings as above.) A method for producing an epoxide compound represented by the following.