JP2006028057A - Method for producing liquid epoxy compound - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an advantageous method for producing a high purity liquid epoxy compound which can maintain a low viscosity applicable to various applications of diluents, particularly liquid sealing media in the application of electronic materials and can improve reliability. <P>SOLUTION: The liquid epoxy compound represented by formula (2) and having an epoxy equivalent of 125-132 and a total chlorine content of ≤100 ppm is produced by epoxidizing an diallyl ether compound represented by formula (1) with a hydrogen peroxide solution in the presence of potassium carbonate. Here, the diallyl ether compound can be obtained by reacting a dihydroxy compound represented by formula (3) (wherein X is a hydroxyl group) with an allyl halide or a dihalide compound represented by formula (3) (wherein X is a halogen) with allyl alcohol. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing a bifunctional liquid epoxy resin that is excellent in workability due to low viscosity and is easily cured by heating and has excellent mechanical and electrical characteristics. This liquid epoxy resin is useful as a diluent for various applications, particularly as a liquid material for electronic materials.

  Liquid epoxy compounds (also referred to as epoxy resins) are excellent in solubility and mechanical properties, and are therefore used as binders for various applications. However, in order to improve the mechanical properties, a method of increasing the blending of fillers and the like is common, but the viscosity increases and workability deteriorates. In order to prevent this, it is necessary to lower the viscosity of the binder component. In the epoxy compound that is the main component of the binder component, maintaining and improving the mechanical properties of the cured product and reducing the viscosity are generally in a contradictory relationship, and liquid epoxy resin is used as a reactive diluent to solve these problems. Yes. For example, ethylene glycol glycidyl ether, propylene glycol glycidyl ether, glycerin glycidyl ether, trimethylolpropane glycidyl ether, pentaerythritol glycidyl ether, cyclohexanedimethanol glycidyl ether, phenyl glycidyl ether, resorching glycidyl ether, xylylene glycol glycidyl ether (Patent Document 1) ~ 3).

JP-A-4-53821 JP 59-206429 A JP-A-4-142326 JP 2004-83711 A

  In recent digital devices, the density of wiring boards and component packages has increased due to performance improvements such as higher data capacity and higher processing speed. The application has been expanded, and further improvement in performance has been strongly demanded for the reactive diluent used in the application.

Among the above compounds, aliphatic cyclic and aliphatic epoxy resins are in the lowest viscosity class and have an excellent dilution effect. However, aliphatic cyclic and aliphatic epoxy resins have poor yields when glycidyl etherification of alcoholic hydroxyl groups, and unreacted alcoholic hydroxyl groups remain.
On the other hand, phenolic epoxy resins such as phenol novolac have a relatively low chlorine content, but the viscosity increases with an increase in the number of functional groups. I cannot expect the effect.

  By the way, Patent Document 4 describes that paraxylylene glycol glycidyl ether (abbreviation, PXGGE) is a highly reactive viscosity reducing agent, and also describes a synthesis example thereof. In the method for synthesizing PXGGE described in Patent Document 4, paraxylylene glycol (abbreviation, PXG) is reacted with allyl halide in the presence of an alkaline aqueous solution and tetrabutylammonium bromide to form paraxylylene glycol allyl ether (abbreviation). PXGAE), and then reacting PXGAE with m-chloroperbenzoic acid (abbreviation, mCPBA) in a methylene chloride solvent to obtain the desired PXGGE. PXGGE obtained by this method is a colorless and transparent liquid substance, and is reported to have an epoxy equivalent of 130 g / eq, a hydroxyl group concentration of less than 0.1 eq / kg, and a total chlorine content of 30 ppm. However, this method has room for improvement in the oxidizing agent and reaction yield in the process of oxidizing PXGAE to PXGGE. In other words, when mCPBA is used for the oxidation reaction, 1) there is a risk of explosion, it is difficult to use a large amount, 2) it is an expensive chemical, and 3) a halogenated solvent such as dichloromethane is used as the solvent for the reaction. 4) Since chloro contained in the mCPBA structure, there was a problem that the total amount of chlorine in PXGGE might increase.

  An object of the present invention is to provide a method for producing a high-purity liquid epoxy compound capable of maintaining a low viscosity and improving reliability, which can be applied to a diluent for various uses, particularly a liquid sealing material for electronic materials. is there.

（但し、Xはヒドロキシ基又はハロゲンを示す） The present invention provides a liquid epoxy compound represented by the following formula (2), wherein the diallyl ether compound represented by the following formula (1) is epoxidized with hydrogen peroxide in the presence of potassium carbonate. Is the method. Here, the diallyl ether compound can be obtained by reacting a dihydroxy compound or dihalide compound represented by the following formula (3) with allyl halide or allyl alcohol. The liquid epoxy compound obtained by this production method preferably has an epoxy equivalent of 125 to 132 and a total chlorine content of 100 ppm or less.

(However, X represents a hydroxy group or a halogen)

  The liquid epoxy compound produced by the production method of the present invention is paraxylylene glycol glycidyl ether (PXGGE) represented by the above formula (2). This PXGGE is generally obtained by reacting a dihydroxy compound (PXG) or a dihalide compound (p-di-halomethyl-benzene; abbreviated PHB) represented by the formula (3) with allyl halide or allyl alcohol. It can be obtained by epoxidizing (oxidizing) PXGAE represented by the formula (1) with hydrogen peroxide in the presence of potassium carbonate.

  Although there is no restriction | limiting in the manufacturing method of PXGAE represented by General formula (1), The method of making PXG or PHB represented by Formula (3) react with allyl halide or allyl alcohol is suitable. In this case, PXG is reacted with allyl halide and PHB is reacted with allyl alcohol.

  The synthesis of PXGE from PXG can be performed, for example, as follows. After dissolving PXG and allyl halide such as allyl chloride and allyl bromide in dimethylsulfoxide, a quaternary ammonium salt such as tetraalkylammonium halide such as tetrabutylammonium bromide or tetraarylammonium halide such as tetraphenylammonium chloride. Then, an aqueous alkali solution such as sodium hydroxide is added dropwise while maintaining the reaction temperature at 40 ° C. or lower. After completion of dropping, the reaction is carried out at 30 to 40 ° C. for about 6 hours.

  As the alkaline aqueous solution, aqueous solutions of sodium hydroxide, calcium hydroxide, potassium hydroxide and the like are preferable. As the usage-amount of an alkali, 2-8 equivalent with respect to 1 equivalent of hydroxyl groups of PXG, More preferably, 4-6 equivalent is good. Moreover, the addition amount of the quaternary ammonium salt which is a catalyst has preferable 0.001-0.1 mol with respect to 1 mol of PXG. Furthermore, the amount of allyl halide used is preferably 2 to 4 moles with respect to 1 mole of PXG.

  After completion of the allylation reaction, the reaction solution is cooled to around room temperature, separated by adding an organic solvent such as toluene, and then the obtained organic layer is concentrated and further purified by distillation or a silica gel short column. Thus, PXGAE represented by the above formula (1) can be obtained. The purity of this PXGAE is 95% or more, preferably 98% or more.

  Moreover, the synthesis | combination of PXGAE represented by Formula (1) from PHB can be performed as follows, for example. After dissolving PHB and allyl alcohol in dimethylsulfoxide, a quaternary ammonium salt such as tetraalkylammonium halide such as tetrabutylammonium bromide or tetraarylammonium halide such as tetraphenylammonium chloride is added, and the reaction temperature is increased to 80. An alkaline aqueous solution such as sodium hydroxide is added dropwise while keeping the temperature below ℃. After completion of dropping, the reaction is carried out at 80 ° C. for about 4 hours.

  As the alkaline aqueous solution, aqueous solutions of sodium hydroxide, calcium hydroxide, potassium hydroxide and the like are preferable. As the usage-amount of an alkali, 2-10 times equivalent with respect to allyl alcohol, More preferably, 4-8 times equivalent is good. Moreover, the addition amount of the quaternary ammonium salt as a catalyst is preferably 0.001 to 0.1 mol with respect to 1 mol of PHB. Furthermore, the addition amount of allyl alcohol is preferably 2 to 6 mol with respect to 1 mol of PHB.

  The epoxy compound PXGGE represented by the formula (2) can be synthesized from the diallyl ether compound PXGAE represented by the formula (1) obtained as described above, for example, as follows. To PXGAE, a solvent such as alcohol such as methanol and ethanol, a nitrile compound such as acetonitrile and benzonitrile, and potassium carbonate are added. Under stirring, 5 to 40%, preferably 30 to 35% hydrogen peroxide solution is dropped, After completion of dropping, the epoxidation reaction is carried out for 0.5 to 10 hours, preferably 1 to 6 hours. It is desirable to add the hydrogen peroxide solution as the oxidizing agent in an amount of 5 to 15 times mol per mol of PXGAE. Although the temperature at which the liquid phase is maintained is adopted as the reaction temperature, it is usually 45 ° C. or lower, preferably 20 to 40 ° C. near normal temperature. The reaction does not proceed at low temperatures, and side reactions become intense at high temperatures.

  The organic solvent used for the epoxidation reaction is preferably a mixture of alcohols such as methanol and ethanol and nitriles such as acetonitrile and benzonitrile. The mixing ratio of alcohols and nitriles is preferably a molar ratio of alcohol: nitrile = 0: 100 to 90:10, particularly preferably 50:50 to 80:20. The concentration of PXGAE dissolved in the solvent is preferably in the range of 0.1 to 1.5 mol / L, particularly preferably in the range of 0.2 to 1.0 mol / L. 0.2-4 mol is preferable with respect to 1 mol of PXGAE, and, as for the addition amount of potassium carbonate, the range of 1.6-2.4 mol is more preferable.

  After completion of the epoxidation reaction, a liquid separation treatment is performed by adding an organic solvent such as toluene, followed by washing with an aqueous sodium sulfite solution and saturated brine, drying, and then concentration of the organic layer is expressed by the formula (2). An epoxy compound PXGGE can be obtained.

  Since the liquid epoxy compound obtained by the production method of the present invention has few unreacted substances, it becomes a high-purity product. Therefore, the epoxy equivalent (Eq) can also be controlled in the vicinity of the theoretical value. Preferably, the ratio (Eq / Eq ′) of the value Eq ′ obtained by dividing the molecular weight M calculated from the chemical formula by the number 2 of epoxy groups in the molecule and the epoxy equivalent Eq of the obtained liquid epoxy compound is 95-100. % Range. Specifically, the epoxy equivalent of the liquid epoxy compound is in the range of 125 to 132.

  The liquid epoxy compound obtained by the production method of the present invention has few unreacted materials, has a small amount of residual chlorine due to side reactions of the conventional method using epichlorohydrin, and has a total chlorine amount of 100 ppm or less. When used, it can be preferably 50 ppm or less. The epoxy compound of the present invention is PXGGE represented by the formula (2) at 95% or more, preferably 98% or more, and more preferably 99% or more, and contains a small amount of impurities such as a chlorine compound.

  The liquid epoxy compound obtained by the production method of the present invention can be made into a cured product by blending a known acid anhydride type, cationic polymerization catalyst, amine type or imidazole type epoxy curing agent. Moreover, it can also mix | blend with another curable composition as a reactive diluent.

  According to the production method of the present invention, a high-purity epoxy compound can be obtained in a relatively high yield. And, by using an inexpensive hydrogen peroxide solution that is easy to handle in the epoxidation reaction, safety can be improved, and further, there is no risk of halogen such as chlorine being mixed into the liquid epoxy compound. The solvent can be a mixed solvent of alcohols such as methanol and ethanol and nitriles such as acetonitrile and benzonitrile, and does not require the use of a halogen-based solvent. Since the epoxy compound of the present invention has a low chlorine content and a bifunctional structure at the same time, it is useful as a diluent for various uses, particularly as a liquid sealing material for electronic materials.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

The epoxy equivalent, viscosity, and total chlorine content of the synthesized liquid epoxy compound were measured and evaluated by the following methods.
Epoxy equivalent: Calculated by the perchloric acid method (JIS K7236).
Viscosity: The viscosity at 25 ° C. was measured with an E-type viscometer.
Hydrolyzable chlorine content: 4 g of epoxy resin was extracted with 200 g of distilled water at 121 ° C. and 2 atm for 20 hours, and the amount of chlorine ions in the extract was quantified by ion chromatography.

Synthesis example 1
To a 2 L four-neck glass flask equipped with a stirrer, thermometer, reflux condenser, and dropping device, 45.2 g of PXG, 27 g of dimethyl sulfoxide (DMSO), 1.1 g of tetrabutylammonium bromide, 75 g Of allyl chloride was added and 150 g of 47% aqueous sodium hydroxide solution was added dropwise over 1 hour with stirring at room temperature. After completion of dropping, the mixture is stirred for 6 hours at room temperature. After completion of the reaction, 110 g of water, 65 g of toluene and 32 g of 5% aqueous hydrochloric acid are added. After separation, the organic layer is washed 3 times with 100 g of saturated brine and dried over anhydrous magnesium sulfate. Concentration of the solvent without the desiccant gave 71.3 g of concentrate. This was distilled under reduced pressure (boiling point 137-139 ° C./3 mmHg) to obtain 62.4 g of PXGAE. Yield 87.4%, GC purity 98%.

Synthesis example 2
57.3 g of α, α′-dichloro-p-xylene, 27 g of DMSO, 1.1 g of tetrabutylammonium bromide and 45.6 g of allyl alcohol were added and 165 g of 47% aqueous sodium hydroxide solution was stirred at 80 ° C. Is added dropwise over 1.2 hours. After completion of dropping, the mixture is stirred at 80 ° C. for 4 hours. After completion of the reaction, 110 g of water, 65 g of toluene and 40 g of 5% hydrochloric acid aqueous solution are added. After separation, the organic layer was washed with a saturated saline solution in the same manner as in Synthesis Example 1, dried over anhydrous magnesium sulfate, the desiccant was removed, and the solvent was concentrated to obtain 74.2 g of concentrate. It was. This was distilled under reduced pressure) to obtain 60.6 g of PXGAE. Yield 84.9%, GC purity 98%.

Synthesis example 3
In a 5 L four-neck glass flask equipped with a stirrer, thermometer, reflux condenser and dropping device, 62.4 g of PXGAE (obtained in Synthesis Example 1), 408 g of methanol, 168 g of acetonitrile, 80 g Of potassium carbonate. While stirring at room temperature, 380 ml of 30-35% hydrogen peroxide solution is added dropwise while adjusting the temperature of the reaction system to be in the temperature range of 20-40 ° C. After completion of dropping, the mixture is stirred at room temperature for 3 hours. After completion of the reaction, 24 g of sodium chloride and 326 g of toluene are added and stirred for 1 hour. After separation, the organic layer is washed with 432 g of 10% aqueous sodium sulfite solution and 374 g of saturated saline, and dried over anhydrous magnesium sulfate. When the desiccant was removed and the solvent was concentrated, 50 g of concentrated liquid was obtained. This was distilled under reduced pressure (boiling point 182-185 ° C./5 mmHg) to obtain 48 g of PXGGE. The yield was 67% and the GC purity was 98%. The amount of hydrolyzable chlorine was 18 ppm, and the viscosity at 25 ° C. was 25 cps. When PXGAE obtained in Synthesis Example 2 was used, PXGGE was obtained with substantially the same yield and purity.

Claims (4)

Following formula (1)

Wherein the diallyl ether compound represented by formula (2) is epoxidized with hydrogen peroxide in the presence of potassium carbonate:

The manufacturing method of the liquid epoxy compound represented by these. The diallyl ether compound is represented by the following formula (3)

2. The liquid epoxy compound according to claim 1, wherein X is a hydroxy group or halogen, and is obtained by reacting a dihydroxy compound in which X is a hydroxy group with allyl halide. Method. The diallyl ether compound is represented by the following formula (3)

The method for producing a liquid epoxy compound according to claim 1, wherein X is a hydroxy group or halogen, and is obtained by reacting a dihalide compound in which X is halogen and allyl alcohol.   The method for producing a liquid epoxy compound according to claim 1, wherein the epoxy equivalent is 125 to 132 and the total chlorine content is 100 ppm or less.