JPH05213920A - Purification of glycidyl compound - Google Patents

Abstract

PURPOSE:To relatively easily decrease the content of hydrolyzable halogen atom in a glycidyl compound under industrially advantageous condition without causing the lowering of yield and the degradation of the final product such as an increase in epoxy equivalent and an increase in viscosity. CONSTITUTION:Hydrolyzable halogen atoms existing in a glycidyl compound are removed to a hydrolyzable halogen atom content of <=100ppm with a hydrotalcite without causing the degradation and the lowering of yield of the final product. The hydrotalcite is e.g. natural hydrotalcite, synthetic hydrotalcite, their calcined product, etc., e.g. the compound expressed by formula ((a) to (e) are integers of >=0 satisfying the formulas 1<a<5, d<=b, d<=c, b+2c=2a+3 and e<10). The amount of the hydrotalcite is preferably about 0.05-3wt.% based on the glycidyl compound.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an industrial purification method for glycidyl compounds.

[0002]

2. Description of the Related Art Conventionally, for example, the following two methods are known as methods for producing glycidyl compounds. (1) Two-step synthesis method Active hydrogen-containing compounds (for example, alcohols, phenols, carboxylic acids, amines, etc.) and epihalohydrins are present in the presence or absence of a solvent, if desired as an acidic compound or basic as a catalyst. A halohydrin compound is obtained by heating in the presence of a compound to carry out an addition reaction, and then dehydrohalogenation is performed using a basic compound such as sodium hydroxide to ring-close this to obtain a crude product of a glycidyl compound. After that, the salts by-produced in the above reaction and the residue of the basic compound used as the dehydrohalogenating agent are washed with water or separated by filtration, and then the volatile substances are distilled off under heating and reduced pressure, followed by filtration. Get the object.

(2) One-step synthetic method The same active hydrogen-containing compound as described above and epihalohydrins and / or halohydrins are condensed with a basic compound such as sodium hydroxide in the presence or absence of a solvent. To obtain a crude product of the glycidyl compound, and then to obtain the desired product by the same post-treatment method as in the two-step synthesis method.

However, the hydrolyzable halogen atom in the final product is usually 500 to 1000 ppm by either of the above-mentioned one-step synthesis method or two-step synthesis method.
It remains at a moderate concentration.

When the epoxy resin obtained by using such a glycidyl compound as a raw material is used as it is in the field of electronics (eg, transistor, IC, LSI, VLSI), mixed hydrolyzable halogen atoms remain for a long time. Halogen ions are released by the action of moisture or heat absorbed from the ambient air during use of electricity, which corrodes wiring members and substrates such as aluminum, or causes insulation failure, and reduces the reliability of electronic parts. .. Therefore, the hydrolyzable halogen atom in the glycidyl compound needs to be removed as much as possible.

Various methods have been proposed so far for reducing the residual amount of hydrolyzable halogen atoms in a glycidyl compound.

For example, JP-A-60-112812 discloses a post-treatment method with an alkali metal alkoxide. Although the treatment has some effect of removing the hydrolyzable halogen atom, it has a drawback that the epoxy group is cleaved or polymerized at the same time to increase the epoxy equivalent and viscosity of the final product.

Further, JP-A-60-186522 discloses a post-treatment method using a free amine type weakly basic anion exchange resin, but the heat resistance of the ion exchange resin is limited. However, it has a drawback that it requires a post-treatment at a relatively low temperature and requires a long-time post-treatment to obtain the desired effect of removing the hydrolyzable halogen atom.

On the other hand, according to the studies by the present inventors, the excess amount of the basic compound used as the dehydrohalogenating agent in the ring-closing reaction is increased, the ring-closing reaction temperature is set high, and the reaction time is extended. Even if the reaction conditions for dehydrohalogenation are made more severe, the content of hydrolyzable halogen atoms can be reduced to only about 150 ppm, and under such conditions, the deterioration of quality and the decrease in yield similar to those described above are possible. Occurred, and a sufficiently satisfactory result was not obtained (Comparative Example 4 of the present application).

As described above, the purification method for more efficiently removing the hydrolyzable halogen atom in the glycidyl compound and preventing the deterioration of the quality and the yield of the final product has not been established yet. Development was strongly desired.

[0011]

DISCLOSURE OF THE INVENTION The present invention is a novel method capable of reducing the amount of a hydrolyzable halogen atom mixed in a glycidyl compound as relatively easily as possible under industrially advantageous conditions. It is intended to provide a purification method.

[0012]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that the glycidyl compound prepared by a conventionally known method, regardless of whether it is a one-step synthetic method or a two-step synthetic method. By post-treating the reaction crude with a hydrotalcite compound, the content of hydrolyzable halogen atoms can be reduced to 100 ppm or less without causing quality deterioration such as epoxy equivalent and viscosity of the final product and yield reduction. I found what I got.

The method for purifying a glycidyl compound according to the present invention is based on the above findings, and it is possible to remove hydrolyzable halogen atoms mixed in the glycidyl compound by using hydrotalcites. Characterize.

The hydrotalcite compound used in the present invention is a natural hydrotalcite, a synthetic hydrotalcite or a calcined product thereof.
It is a compound having a composition ratio represented by the general formula (1).

[Chemical 1] [Where a, b, c, d and e are 1 <a <5, d ≦
b and d ≦ c, b + 2c = 2a + 3 and e <10 are 0 and a positive integer. ]

The preferred amount of the compound added is about 0.05 to 3% by weight based on the desired glycidyl compound. If it is less than 0.05% by weight, the hydrolyzable halogen atom cannot be sufficiently removed, and if it is added in an amount of more than 3% by weight, no significant difference in effect is observed, which is economically disadvantageous.

Specific examples of the processing method will be given below. The processing conditions are not limited as long as a predetermined effect can be obtained. For a reaction crude obtained from active hydrogen-containing compounds and epihalohydrins and / or halohydrins as raw materials, if necessary, an inert solvent for the purpose of lowering the viscosity of the system (for example, benzene, toluene, xylene, Hexane, heptane, octane, methyl ethyl ketone, methyl isobutyl ketone, etc.), and then
By-produced salts and unreacted basic compounds are removed by appropriately combining steps such as filtration, washing with water and centrifugation.

Thereafter, a predetermined amount of the hydrotalcite compound is added, and usually under a temperature condition of about 80 to 130 ° C., preferably under a reduced pressure of about 3 to 20 mmHg, 0.5.
Stir for about 3 hours. In this process, the volatile substances mixed in the reaction crude such as water and solvent may be distilled off at the same time, or the volatile substances may be distilled off in advance under heating and reduced pressure, and then the hydrotalcite compound. May be used for purification. When the temperature condition is 80 ° C. or lower, the removal efficiency of the hydrolyzable halogen atom tends to decrease, and it is industrially disadvantageous because a large amount of the hydrotalcite compound needs to be used.

Thereafter, the system is filtered or centrifuged to collect and remove the solid matter, so that the hydrolyzable halogen atom can be obtained without increasing the epoxy equivalent or viscosity due to polymerization or cleavage of the epoxy group. A glycidyl compound having a significantly reduced content of is obtained.

[0019]

EXAMPLES The present invention will be described in detail below with reference to examples. The evaluation method in each example is as follows. Epoxy equivalent: According to the method of titration with perchloric acid. Hydrolyzable chlorine content: sodium methylate 60 to 7
After hydrolyzable chlorine is ionized by acting at 0 ° C. for 5 minutes, it is titrated with silver nitrate. Viscosity (25 ° C) -By B type rotational viscometer.

As the hydrotalcite compound, the following synthetic hydrotalcite manufactured by Kyowa Chemical Industry Co., Ltd. was applied. Kyoward 2000 (Mg _0.7 Al _0.3 O _1.15 ) Kyoward 1000 (Mg _4.5 Al ₂ (OH) ₁₃ CO ₃
・ MH ₂ O, m = 3 to 3.5) Kyoward 500SN (Mg ₆ Al ₂ (OH) ₁₆ CO ₃
・ 4H ₂ O) Kyoward 500 SH (Mg ₆ Al ₂ (OH) ₁₆ CO ₃
・ 4H ₂ O)

Example 1 A reactor equipped with a rotary stirrer, a decanter, a thermometer and a gas inlet tube was used to prepare 243 g of hydrogenated bisphenol A (1.
0 mol), 116 g of xylene and 3.1 g of stannic chloride pentahydrate (addition reaction catalyst) were added, and after adding 222 g (2.4 mol) of epichlorohydrin at 100 ° C., stirring was continued to carry out the addition reaction. finished. Then benzyltrimethylammonium chloride (phase transfer catalyst) 6.9
g, after adding 223 g of 50% sodium hydroxide aqueous solution,
The ring-closing reaction was completed by continuing stirring at 80 ° C. for 5 hours. By-produced sodium chloride and unreacted sodium hydroxide were removed by washing with water, 2 g of KYOWARD 2000 was further added, and the mixture was stirred at 130 ° C. and 3 mmHg for 3 hours while dehydration / desolvation was performed. It was filtered off. As a result, epoxy equivalent 215, hydrolyzable chlorine content 30 ppm, viscosity 250
372 g (yield 98.6%) of 0 gP of hydrogenated bisphenol A diglycidyl ether was obtained.

Example 2 In the same reactor as in Example 1, 246 g (0.5 mol) of 6 mol adduct of bisphenol A.ethylene oxide, 463 g (5.0 mol) of epichlorohydrin, 5.5 g of benzyltrimethylammonium chloride, 100 g of 50% aqueous sodium hydroxide solution was charged, and the condensation reaction was completed by stirring for 4 hours while azeotropically dehydrating under reflux of epichlorohydrin at 50 ° C. By-produced sodium chloride and unreacted sodium hydroxide were removed by washing with water, and excess epichlorohydrin was recovered under heating and reduced pressure, 2 g of Kyoward 1000 was added, and the mixture was stirred at 120 ° C. and 5 mmHg for 1 hour. .. Then, the mixture was filtered to obtain 287 g (yield 95.0%) of diglycidyl ether of a 6 mol adduct of bisphenol A / ethylene oxide having an epoxy equivalent of 315, a hydrolyzable chlorine content of 50 ppm and a viscosity of 950 cP.

Example 3 A reactor similar to that used in Example 1 was charged with trimethylolpropane 1
34 g (1.0 mol), xylene 41 g and boron trifluoride ether complex salt 4.3 g were charged, epichlorohydrin 277 g (3.0 mol) was added dropwise at 60 ° C., and stirring was continued to complete the addition reaction. Then, 120 g of solid sodium hydroxide was added, and stirring was continued at 40 ° C. for 1 hour to complete the ring closure reaction. By-produced sodium chloride and unreacted sodium hydroxide were separated by filtration and 2 at 80 ° C and 3 mmHg.
After dehydration and solvent removal for 8 hours, Kyoward 500SN is turned on 8
g, and the mixture was stirred at 80 ° C. under normal pressure for 2 hours. afterwards,
Filtered to have an epoxy equivalent of 122 and a hydrolyzable chlorine content of 9
298 g (yield 98.8%) of trimethylolpropane triglycidyl ether having 0 ppm and a viscosity of 110 cP was obtained.

Example 4 In a reactor similar to that of Example 1, 168 g (1.0 mol) of 4-methylhexahydrophthalic anhydride, 250 g (2.7 mol) of epichlorohydrin, 3.3 g of tetramethylammonium chloride and distillation. After adding 30 g of water and stirring at 80 ° C. to complete the addition reaction, 149 g of toluene was added. Then, azeotropic dehydration was carried out at 80 ° C. while dropping 213 g of a 45% aqueous sodium hydroxide solution to complete the ring closure reaction. By-produced sodium chloride and unreacted sodium hydroxide were separated by filtration, dehydrated and desolvated at 120 ° C. and 5 mmHg for 2 hours, 3 g of Kyoward 500SH was added, and the mixture was further stirred for 30 minutes. Then, filter to obtain an epoxy equivalent of 17
1. Hydrolyzable chlorine content 60ppm, viscosity 4 520cP
295 g (yield 92.4%) of methyl hexahydrophthalic anhydride diglycidyl ester were obtained.

Comparative Example 1 The hydrogenated bisphenol A of interest was obtained by treating in the same manner as in Example 1 except that Kyoward 2000 was not added.
Diglycidyl ether of 375 g (yield 99.4%)
Was obtained. By the way, the epoxy equivalent of this product is 21
3. Hydrolyzable chlorine content is 260ppm, viscosity is 2500
It was cP.

Comparative Example 2 The treatment was carried out in the same manner as in Example 2 except that Kyoward 1000 was not added, and the target diglycidyl ether of bisphenol A / ethylene oxide 6 mol adduct was 290 g (yield 96.0%). Was obtained. By the way, this product has an epoxy equivalent of 315 and a hydrolyzable chlorine content of 2
It was 40 ppm and the viscosity was 950 cP.

Comparative Example 3 The treatment was carried out in the same manner as in Example 3 except that Kyoward 500 SN was not added, and as a result, the target trimethylolpropane triglycidyl ether was 299 g (yield 99.1).
%) Obtained. By the way, the epoxy equivalent of this product is 1
20, hydrolyzable chlorine content 690ppm, viscosity 110
It was cP.

Comparative Example 4 The ring-closing reaction was carried out at 60 ° C. for 3 hours with stirring, and the treatment was carried out in the same manner as in Example 3 except that Kyoward 500 SN was not added. As a result, 271 g of the desired trimethylolpropane triglycidyl ether Yield 89.8%) was obtained. Incidentally, this product had an epoxy equivalent of 190, a hydrolyzable chlorine content of 150 ppm, and a viscosity of 220 cP.

Comparative Example 5 The same treatment as in Example 4 was carried out except that Kyoward 500SH was not added, and 297 g (yield 93.0%) of the target 4-methylhexahydrophthalic anhydride diglycidyl ester was obtained. It was Incidentally, this product had an epoxy equivalent of 173, a hydrolyzable chlorine content of 310 ppm, and a viscosity of 520 cP.

[0030]

EFFECTS OF THE INVENTION The method for purifying a glycidyl compound according to the present invention makes it easier and easier to produce a hydrolyzable halogen atom without causing quality deterioration such as increase in epoxy equivalent of the final product, increase in viscosity and decrease in yield. It is possible to significantly reduce the residual amount.

Claims (1)

[Claims] 1. A method for purifying a glycidyl compound, which comprises removing hydrolyzable halogen atoms mixed in the glycidyl compound using hydrotalcites.