JPS59175482A - Preparation of epoxy compound - Google Patents

Abstract

PURPOSE:To obtain the titled compound inexpensively in a short time, by reacting a specific amount of a diaminodiphenylmethane derivative with epichlorohydrin, dehydrochlorinating the reaction product with an alkali metal hydroxide. CONSTITUTION:1mol diaminodiphenylmethane shown by the formula (X is H, Cl, Br, I, or 1-4C alkyl) or alkyl-substituted compound or halogen-substituted compound of it and 4-6mol epichlorohydrin are subjected to addition reaction in ethyl alcohol and a mixed solvent of water and aromatic hydrocarbon. The reaction product is then dehydrochlorinated with an alkali metal hydroxide to give the desired compound. 10-80pts.wt. water-soluble alcohol and 20-250pts.wt. total amounts of water and aromatic hydrocarbon are used based on 100pts.wt. diaminodiphenylmethane. USE:Useful as a resin material for reinforcing carbon fiber, sealing material or casting material for electrical parts.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a liquid tetraglycidyl compound of diaminodiphenylmethane in a short time, which provides a cured product with excellent heat resistance in the presence of a curing agent. The polyepoxy compound obtained by carrying out the present invention provides a cured product with excellent heat resistance, and is therefore useful as a carbon fiber reinforced resin (hereinafter referred to as rcFRP) material, a material for electrical parts, or a casting material.

CFRP, which is obtained from the tetraglycidyl compound represented by the general formula, carbon fiber, and a hardening agent, is a cured product with excellent heat resistance and mechanical strength, so it is used as a laminated material and casting material for aerospace equipment and small computers. ing.

This tetraglycidyl compound is prepared by adding 1 mole of diaminodiphenylmethane and 12 to 16 moles of epichlorohydrin, causing an addition reaction in an alcohol solvent, and then adding sodium hydroxide to the reaction product to perform a dehydrochlorination reaction. It is obtained by

The reason why alcohol is used as a solvent is that the raw material diaminodiphenylmethane is solid and has low solubility in epichlorohydrin.This alcohol is a good solvent for diaminodiphenylmethane and has a saponifiable chlorine content of 0.5. This is because it provides a polyepoxy compound of less than % by weight. Even if ethylene glycol, which is a good solvent for diaminodiphenylmethane, is used, the saponifiable chlorine content of the polyepoxy compound obtained is 5 to 8% by weight.
That's high.

Traditionally, ethyl alcohol is diaminodiphenylmethane1
It is used in an amount of at least 80 parts by weight per 00 parts by weight. This is because if it is less than 80 parts by weight, the viscosity of the reaction system increases as the addition reaction progresses, and the reaction liquid becomes pasty or semi-solid, making stirring difficult and requiring a long reaction time. Therefore, ethyl alcohol is 100 parts by weight for 100 parts by weight of diaminodiphenylmethane.
It is generally used in a proportion of ~300 parts by weight.

However, ethyl alcohol has good compatibility with epichlorohydrin and their boiling points are close to each other, so after the reaction,
Since the recovered unreacted epichlorohydrin contains 8 to 12% by weight of ethyl alcohol, it is necessary to separate the ethyl alcohol from the recovered epichlorohydrin in order to reuse it, and the recovered epichlorohydrin cannot be used as is. In this case, it is necessary to measure the ethyl alcohol content in the recovered epichlorohydrin and newly determine the amount of fresh epichlorohydrin and ethyl alcohol to be added to diaminodiphenylmethane, which is not an industrially advisable solution. That is, the cost required for recovering epichlorohydrin and separating alcohol is not significantly different from the cost for purchasing new epichlorohydrin.

The present inventors reduced the number of moles of epichlorohydrin used per mole of diaminodiphenylmethane, and
If the amount of alcohol used can be reduced, the amount of alcohol used can be reduced to 80 parts by weight or less for 100 parts by weight of diaminodiphenylmethane by using a mixed solvent consisting of unreacted epichlorohydrin alcohol and aromatic hydrocarbons. , and the amount of epichlorohydrin charged per mole of diaminodiphenylmethane is also 4
The present invention was achieved by discovering that the scale can be reduced to ~6 moles.

That is, the present invention involves an addition reaction between epichlorohydrin and diaminodiphenylmethane, an alkyl-substituted product thereof, or a halogen-substituted product thereof (hereinafter referred to as "diaminodiphenylmethane"), and then injecting the reaction product with alkali metal water as a ring-closing agent. In a method for producing a tetrafunctional epoxy compound by adding an oxide and performing a dehydrochloric acid reaction, 4 to 6 moles of epichlorohydrin are charged per mole of diaminodiphenylmethane, and the addition reaction is carried out with water and a water-soluble alcohol. The present invention provides a method for producing a polyepoxy compound, characterized in that the process is carried out in a mixed solvent with an aromatic hydrocarbon.

In the present invention, diaminodiphenylmethane or its alkyl-substituted product or its halogen-substituted product that reacts with epichlorohydrin is represented by the general formula (II) [wherein, X is H
or α, Br, I, or an alkyl group having 1 to 4 carbon atoms], specifically 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane,
2.3'-diaminodiphenylmethane, 2.4'-diaminodiphenylmethane, 2.2'-diaminodiphenylmethane, 2.4'-diamino-3,3'-short-diphenylmethane, 2.2'-diamino-5,57 -dibromo-diphenylmethane, 4,4'-diamino-3,3
'-dichloro-diphenylmethane and the like.

Among these, 4,4'-diaminodiphenylmethane is preferred because it provides a cured product with better heat resistance.

In the addition reaction [first step] of diaminodiphenylmethane or its alkyl-substituted product or its halogen-substituted product (hereinafter represented by diaminodiphenylmethane) and epichlorohydrin, 4 to 6 moles of epichlorohydrin are added per mole of diaminodiphenylmethane, preferably 4 to 6 moles of epichlorohydrin. is 4~
5 mol of the mixed bath/water per 100 parts of diaminodiphenylmethane, specifically 10 to 80 parts by weight of water-soluble alcohol, 10 parts by weight or more of water, and aromatic hydrocarbons. 10 to 2-00 parts by weight, and the sum of water and aromatic hydrocarbon is 20 to 250 parts by weight in a mixed solvent at 40 to 100°C.
Addition reaction for 12 hours, preferably 5 to 10 hours [first stage]
This is done by letting Note that epichlorohydrin can also be added in portions.

Examples of the water-soluble alcohol include low boiling point alconyls with a boiling point of 100°C or less, such as methyl alcohol, ethyl alcohol, isopropyl alcohol, butyl alcohol, and octatool, as well as boiling points such as ethylene glycol, diethylene glycol, glycerin, and pentaerythritol. Alcohol whose temperature is 120°C or higher can be used. Among these, ethyl Alcohol is best. In order to obtain a polyepoxy compound with a saponifiable chlorine content of 0.5% by weight or less using a water-soluble alcohol other than ethyl alcohol, such as isopropyl alcohol or ethyl alcohol, in the subsequent dehydrochlorination reaction, N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-
It is necessary to carry out the dehydrochlorination reaction by adding 5 to 100 parts by weight of amines such as 2-pyrrolidone and hexamethylphosphoramide to 100 ft parts of the raw material diaminodiphenylmethane.

These water-soluble alcohols are diaminodiphenylmethane 1
00 parts by weight, 10 to 80 parts by weight, preferably 15 parts by weight
~50 parts by weight is used. If the amount is less than 10 parts, the effect of diaminodiphenylmethane as a solvent cannot be exhibited, and as the addition reaction progresses, the viscosity of the reaction system increases, making stirring difficult.

Even if more than 80 parts by weight is used, no further improvement in the effect as a solvent can be expected. Furthermore, it is difficult to recover and reuse these alcohols, which is unfavorable in terms of cost.

Water and aromatic hydrocarbons are diaminodiphenylmethane 10
0 parts by weight, the sum of both is 20 to 250 parts by weight, preferably 40 to 200 parts by weight, and water is added to 1 part by weight.
The aromatic hydrocarbon is used in an amount of 0 parts by weight or more, and 10 to 200 parts by weight. The sum of water and aromatic hydrocarbon usage is 20
If the amount is less than 250 parts by weight, the effect as a diluting solvent for the reaction solvent and alcohol will not be sufficient, and if it exceeds 250 parts by weight, no further improvement in the effect as a solvent can be expected. It is disadvantageous in that it takes a long time to remove and the charge of diaminodiphenylmethane and epichlorohydrin, which are the main raw materials to the reactor, is reduced.As aromatic hydrocarbons, the boiling point is 80 to 160.
℃ is preferable, and evabenzene, toluene, xylene, etc. are used, and among these, toluene (J) is preferable from the viewpoint of reaction temperature and purification of the polyepoxy compound. If the amount of aromatic hydrocarbon used is less than 10 parts, the viscosity of the reaction system increases as a polyepoxy compound is produced during the ring-closing reaction, making stirring difficult. On the contrary, 2
It is not preferable to use more than 0.00 parts by weight because it lowers the addition reaction rate.

Further, if the amount of water used is less than 10 parts by weight, the effect as a diluting solvent for the water-soluble alcohol and a solvent for the raw material epichlorohydrin is not sufficient. By using water and an aromatic hydrocarbon in combination, the amount of water-soluble alcohol used can be reduced and the addition reaction time can be shortened.

The shortening of the addition reaction time was attributed to the contribution of the water-soluble alcohol.

The completion of the addition reaction is confirmed by the disappearance of 1 to 3 moles of epichlorohydrin adduct to diaminodiphenylmethane by gel permeation column analysis or liquid chromatography analysis (Japanese Patent Application No. 123648/1982).
.

Next, in the subsequent dehydrochlorination reaction, a predetermined amount of alkali metal hydroxide is gradually added to the addition reaction product, and the dehydrochlorination reaction is carried out for 2 to 10 hours at a temperature of 70°C or less [second stage]. This is done by At this time, when the water-soluble alcohol used in the discrimination reaction time is other than ethyl alcohol, the above-mentioned N, N-dimethylformamide, N,N-dimethylacetamide,
Add amines such as N-methyl-2-pyrrolidone and hexamethylphosphoramide.

As the alkali metal hydroxide used in the subsequent dehydrochlorination reaction, thorium hydroxide and potassium hydroxide are suitable, and although these can be used in solid form, it is preferable to add them to the reaction system as an aqueous solution.

The amount of alkali metal hydroxide added varies depending on the amount of remaining epichlorohydrin, but is generally 4 to 5 mol per mol of diaminodiphenylmethane as the raw material.
Preferably it is 4.4 to 4.8 mol.

In addition, when adding a solvent for amines, 2 to 50
It is used in an amount of 3 to 20 parts by weight, preferably 3 to 20 parts by weight.

After the dehydrochloric acid reaction is completed, unreacted epichlorohydrin, water-soluble alcohol, aromatic hydrocarbons, water, etc. are distilled off under reduced pressure, and the residue is mixed with water-compatible materials such as toluene, xylene, and methylene isoptyl ketone. The mixture was washed several times with water to dissolve by-produced alkali metal salts, remaining amines, and water-soluble alcohols (boiling point 1).
When using alcohol at 20°C or higher), remove it with water or wash it several times with water without distilling it off under reduced pressure to remove unreacted epichlorohydrin, water-soluble alcohol, by-produced alkali metal salts, residual amines, etc. It can also be removed.

Thereafter, the solvent having poor compatibility with water is distilled off to obtain the desired tetrafunctional epoxy compound.

The tetrafunctional epoxy compound thus obtained is a pale yellow to yellow viscous substance with a viscosity of 2100 at 25°C.
0-5,000 poise, viscosity at 50°C 25-1
50 poise, and its saponifiable chlorine content is as low as 0.5% by weight or less.

This tetrafunctional epoxy compound mixed with a curing agent and cured by heating is a cured product that has excellent heat resistance, is tough, and is insoluble in organic solvents.

Such curing agents include, for example, amino compounds having at least one hydrogen atom directly bonded to a nitrogen atom, such as diethylenetriamine, triethylenetetramine, xylenodiamine, methanelenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, aniline formaldehyde resins: Adducts of these amino compounds with other compounds such as epoxy group-containing compounds, acrylonitrile, and acrylic esters, such as polyamide amines derived from aliphatic polyamines and dimer acids of unsaturated fatty acids: polycarboxylic acids or their anhydrides thing,
For example, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, maleic anhydride, dodecenyl co-phosphoric anhydride, etc.; polythiols, such as bis-(2-
Hydrothionityloxy)methane, etc.: Secondary to tertiary amines, such as benzyldimethylamine, tris-(
Examples include dimethylamine (methyl) phenol, imidazole, pyridine, piperidine, triethanolamine, etc.; and dicyandiamide, BFa/amine salts, etc.

According to the production method of the present invention, the amount of expensive epichlorohydrin and alcohol used can be reduced, the dehydrochlorination reaction can be completed in a short time, and the saponifiable chlorine content of the resulting tetrafunctional polyevoquine compound can be reduced to 50%. It has the advantage of being less than % by weight.

The present invention will be explained in more detail with reference to Examples below. Note that parts and percentages in the examples are based on weight.

(Leaving space below) Example 1 In a 40 glass flask with an internal volume of 1 ton, diaminodiphenylmethane 3ON (0.15 mol), 69 parts of epichlorohydrin (0.75 mol), 8 parts of ethyl alcohol, 8 parts of toluene, and 20 parts of water were placed. The addition reaction was carried out at 50° C. for 10 hours. It was confirmed by gel permeation column analysis that the addition reaction was complete.

Next, 60 parts (0.72 mol) of a 48% aqueous sodium hydroxide solution was added dropwise into the flask over about 1 hour while keeping the temperature of the reaction solution below 50°C, and the mixture was stirred at the same temperature for 5 hours. The ring-closing reaction was completed.

Thereafter, the pressure inside the reaction system was reduced (20 to 30++ mHg), and unreacted raw materials, ethyl alcohol, toluene, water, etc. were distilled off at about 60°C.

Next, 200 parts of methyl in butyl ketone, 7
After adding 300 parts of water at 0°C and stirring for about 15 minutes, the aqueous layer was removed. After washing the organic layer twice using 250 parts of water in the same manner (the pH of the aqueous layer at this time is approximately 7), the organic layer was subjected to vacuum distillation at 125°C and approximately 20 to 30 wHg, and methyl The tetrafunctional epoxy compound 65 represented by the general formula (1) as a residue after distilling off isobutyl ketone
I got the department.

The obtained product was a pale yellow viscous liquid, and its physical properties were as follows.

Epoxy equivalent weight 120 Viscosity (50°C) 32 Poise donor hue 4 Saponifiable chlorine content 0.1'70 Production example of cured product 100 parts of the tetrafunctional epoxy compound obtained in Example 1 and 52 parts of diaminodiphenylsulfone as a curing agent Mix 14
After degassing at 0°C, it is poured into a mold and heated at 180°C for 1 hour and 190°C for 3 hours to perform a curing reaction.
After cooling to 40° C., the cured product was released from the mold to obtain a product measuring 12 inches long, 120 inches wide, and 6 inches thick.

The heat distortion temperature (ASTM D-648) of this product is 2
40°C, tensile modulus (JIS K-6911)
was 38,500 disorders/d.

However, the electrical properties were as follows.

Example 2 In a 40 glass flask with an internal volume of 1 t, 30 liters of diaminodiphenylmethane (0.15 mol), 69 parts of epichlorohydrin (o, 75 mol), 13 parts of Improvil alcohol, 8 parts of toluene and 15 parts of water were charged, 6
The addition reaction was carried out at 0°C for 10 hours.

Complete completion of the addition reaction was confirmed by gel permeation column analysis.

Next, after adding 5 parts of N,N-dimethylformamide into the flask, 48% sodium hydroxide aqueous iCo part (0.72 mol) was added into the flask while keeping the temperature of the reaction solution below 50°C. Therefore, it is dripped for about 1 hour,
The ring-closing reaction was completed by stirring at the same temperature for 2 hours.

After that, reduce the pressure in the reaction system (20-30 + m Hg)
Unreacted raw materials, isopropyl alcohol, toluene, water, etc. were distilled off at about 60°C.

Next, 200 parts of methylinobutyl ketone, 7
After adding 300 parts of water at 0°C and stirring for about 15 minutes, the aqueous layer was removed. After washing the organic layer twice with 250 parts of water in the same manner (the pH of the aqueous layer at this time is about 7), the organic layer was distilled under reduced pressure at 125°C and about 20 to 30 wm Kg. , methyl in butyl ketone and N,N-dimethylformamide are distilled off to form a residue represented by the general formula (1).
66 parts of a tetrafunctional epoxy compound represented by was obtained.

The obtained product was a pale yellow viscous liquid, and its physical properties were as follows.

Epoxy equivalent weight 121 Viscosity (25°C) 40 Poise donor hue 5 Saponifiable chlorine content 0.1% Example 3 In a 40 glass flask with an internal volume of lt, 30 parts of diaminodiphenylmethane (0, tss mol, 69 parts of epichlorohydrin) : 0.7 s mol), 10 parts of water, 10 parts of toluene, and 16 il of ethylene were added, and the addition reaction was carried out at 40°C for 8 hours. The completion of the addition reaction was determined by gel permeation column analysis. Confirmed by.

Next, after adding 5 parts of N,N-dimethylacetamide into the flask, 60 parts of 48% sodium hydroxide aqueous solution (0.72 molar) was added into the flask while keeping the temperature of the reaction solution below 50°C. The mixture was added dropwise over about 1 hour and stirred at the same temperature for 2 hours to complete the ring-closing reaction.

After that, the pressure inside the reaction system was reduced (20 to 30 mHg),
After distilling off unreacted raw materials and water at about 60°C, 200 parts of methyl isobutyl ketone and 7
After adding 300 parts of water at 0°C and stirring for about 15 minutes, the aqueous layer was removed. After washing the organic layer twice using 250 parts of water in the same manner (the pH of the aqueous layer at this time is about 7), the organic layer was subjected to vacuum distillation at 125°C and about 20 to 30 #Hg. , methylinobutylketone, ethylene glycol and N,N-dimethylacetamide were distilled off to obtain 62 parts of a tetrafunctional epoxy compound represented by the general formula (1) as a residue.

The obtained product was a pale yellow viscous liquid, and the physical properties were as follows: Epoxy equivalent: 122 Viscosity (50°C): 42 Boise donor hue: 5 Saponifiable chlorine content: 0.1% Example 4 Example 1 After the ring-closing reaction was completed, 200 parts of toluene and 300 parts of water at 70°C were added to the reaction solution, and about 1
After stirring for 5 minutes, the aqueous layer was removed.

After washing the organic layer three times using 300 parts of water in the same manner, the organic layer was subjected to vacuum distillation at 125° C. and about 10 to 20 ttrm Kg to remove toluene and form a residue according to the general formula (1). 64 parts of a tetrafunctional epoxy compound represented by was obtained.

The obtained product was a pale yellow viscous liquid, and its physical properties were as follows.

Epoxy equivalent 121 Viscosity (50°C) 30 Poise Donor hue 3 Saponifiable chlorine content 0.1% Comparative example 1 In a 40 glass flask with an internal volume of 1 ton, 30 parts (o, 1 part mole) of diaminodiphenylmethane, 69 parts of epichlorohydrin (0.75 mol) and 6 parts of ethyl alcohol were charged, and an addition reaction was carried out at 50°C. After 10 hours, the viscosity of the reaction system rose to TL, which made stirring difficult, so the reaction was stopped.

When a part of the reaction solution was sampled and the progress of the addition reaction was investigated by gel permeation column analysis, it was found that 2 epichlorohydrin was added to diaminodiphenylmethane.
The substance added in an amount of 3 to 3 moles accounted for the main component of the reaction solution.

Comparative Example 2 (Conventional Method) In a 40 glass flask with an internal volume of 1 ton, 30 g (0.15 mol) of diaminodiphenylmethane, 224 parts (2.40 mol) of epichlorohydrin, and 30 parts of onihyethyl alcohol were charged, and the flask was heated to 8 ml at 40°C. After reacting for an hour, a portion of the reaction solution was sampled and gel permeation column analysis revealed that the addition reaction had not completed, so the reaction was continued for another 8 hours at the same temperature and then sampled again. The same analysis confirmed that the addition reaction was completely completed.

Next, 60 parts (0.72 mol) of a 48% aqueous sodium hydroxide solution was added dropwise into the flask over about 1 hour while keeping the temperature of the reaction solution below 50°C, and the mixture was stirred at the same temperature for 5 hours to complete the desorption. The hydrochloric acid reaction was completed.

After that, the pressure inside the reaction system was reduced (20 to 30 tar Hg
), unreacted raw material ethyl alcohol, water, etc. were distilled off at about 60° C., and an epichlorohydrin layer and an aqueous layer (containing ethyl alcohol) were separated to recover 158 parts of epichlorohydrin.

This epichlorohydrin contained about 3% by weight of ethyl alcohol.

Next, 200 parts of methyl isobutyl ketone was added to the distillation residue,
After adding 300 parts of water at 70°C and stirring for about 15 minutes, the aqueous layer was removed. Similarly, 250 parts of water was used to separate 2 parts of the organic layer.
After washing twice, the organic layer was heated to 125°C and approximately 20 to 30 m+
Vacuum distillation was carried out at 1 f (g) to remove methylinobutyl ketone, yielding 63 parts of a tetrafunctional epoxy compound represented by the general formula (1) as a residue.

The obtained product was a pale yellow viscous liquid, and its physical properties were as follows.

Epoxy equivalent weight 125 Viscosity (50°C) 40 Poise Donor hue 5 Saponifiable chlorine content 0.4% Comparative example 3 In a 40 glass flask with an internal volume of 1 ton, 307 g (0.15 mol) of diaminodiphenylmethane and 69 parts of epichlorohydrin ( When 0.7s Morn and 13 parts of Improvil alcohol were charged and an addition reaction was carried out at 40C, the viscosity of the reaction solution increased in about 10 hours to such an extent that stirring could no longer be continued, so the addition reaction was terminated.

When a part of the reaction solution was sampled and the progress of the addition reaction was investigated by gel permeation column analysis, it was found that diaminodiphenylmethanievichlorohydrin was
There were many cases where 3 to 3 moles were added.

Examples 5 to 7, Comparative Example 4 In Example 2, N and N used in the subsequent dehydrochloric acid reaction
A polyepoxy compound having the physical properties shown in Table 1 was obtained in the same manner except that the solvent shown in Table 1 was used or not in place of '-dimethylacetamide, and the dehydrochlorination reaction time was changed as shown in Table 1. Ta.

(Left below) Examples 8 to 12, Comparative Example 5 In Example 1, 7 parts of ethyl alcohol and 2 parts of water in a mixed solvent consisting of ethyl alcohol, water and toluene.
A polyepoxy compound having the physical properties shown in Table 2 was obtained in the same manner except that the mixing ratio with 0 parts was changed as shown in Table 2, and the addition reaction time and dehydrochlorination reaction time were changed as shown in the same table. Ta.

(Margin below)

Claims (3)

[Claims] (1) Diaminodiphenylmethane or its alkyl-substituted product or its halogen-substituted product is subjected to an addition reaction with epichlorohydrin, and then an alkali metal hydroxide is added to the reaction product to perform a dehydrochlorination reaction to obtain a tetrafunctional In the method for producing an epoxy compound, the amount of epichlorohydrin charged per mole of diaminodiphenylmethane is 4 to 6 moles, and the addition reaction is carried out in a mixed solvent of a water-soluble alcohol, water, and an aromatic hydrocarbon. A method for producing a polyepoxy compound, characterized by: (2) Manufacturing method 0 according to claim 1, characterized in that the alcohol is ethyl alcohol. (3) To 100 parts by weight of diaminodiphenylmethane, add 10 to 80 parts by weight of water-based alcohol (4) and water (
6) and an aromatic hydrocarbon (0) in a total of 20 to 250 parts by weight, and the aromatic hydrocarbon is 200 parts by weight or less and water is used in a proportion of 10 parts by weight or more. A manufacturing method according to claim 1.