JPH0142931B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for selectively producing bisphenols, which is characterized by reacting a phenolic aldehyde resin with a phenol in the presence of an acid catalyst.

Generally, when bisphenols are produced by a condensation reaction between phenols and aldehydes, a large amount of polynuclear oligomers containing three or more phenol nuclei are produced as by-products, and a sufficiently high selectivity for bisphenols is achieved. It is well known that this is not possible. For example, in the acid-catalyzed reaction of phenol and acetaldehyde, novolak-type phenolacetaldehyde resin is mainly produced [J.
Polymer Science, 4, 689 (1949)], in the reaction of phenol and formaldehyde, 4,4'-methylenebisphenol (generally also called bisphenol F) and a large amount of polynuclear phenolic resin are produced as by-products [Nikka Kyokai Monthly Report 10, 29 (1975)]. Since such by-product oligomers usually have no other effective use other than their general use as phenolaldehyde resins, we have developed a method for producing bisphenols with high selectivity that minimizes the by-product of such oligomers. Although there is a strong demand for the development of such a system, no method has yet been found that can fully satisfy this demand.

On the other hand, in general, novolak-type phenolaldehyde resin, including such by-product oligomers, is treated with acid,
Alternatively, a method of regenerating phenols through a decondensation reaction between acid and water, or in the presence of water, is well known. The method of selectively producing only bisphenols by reacting them below was difficult to infer from conventionally known facts.

The present inventors have conducted intensive research on a method for selectively producing bisphenols from the above-mentioned by-product oligomers and generally novolak-type phenol aldehyde resins. The present invention was completed based on the discovery that bisphenols can be produced with extremely high selectivity by reacting with phenols under appropriate reaction conditions.

That is, the gist of the present invention resides in a method for selectively producing bisphenols, which is characterized by reacting a phenol aldehyde resin with a phenol in the presence of an acid catalyst.

The phenolaldehyde resin used in the method of the present invention generally refers to polynuclear oligomers and high condensates having three or more phenol nuclei produced by the condensation reaction of phenols and aldehydes, and these condensates That is, when a phenolaldehyde resin is used as a raw material in the method of the present invention, there is no problem even if it contains unreacted substances and other reaction products in the above condensation reaction. In addition, the above phenols and the phenols used in the method of the present invention have the general formula [Wherein, X is H, CH ₃ , C ₂ H ₅ , C ₃ H ₇ , C ₄ H ₉ ,
Represents I, Br, Cl or F, etc. ], and the position of the substituent X may be ortho, meta, or para to the hydroxyl group. Furthermore, in the present invention, among the above-mentioned phenols, phenol, cresol, ethylphenol, etc. are particularly preferably used, and these phenols include not only purified pure ones but also crude ones that are generally produced industrially. is also used.

Furthermore, the bisphenols produced by the method of the present invention have the general formula [Wherein, X is H, CH ₃ , C ₂ H ₅ , C ₃ H ₇ , C ₄ H ₉ ,
Represents I, Br, Cl, F, etc., and Y is H or CH ₃
represents. ].

Next, examples of the catalyst used in the method of the present invention include inorganic acids such as hydrochloric acid, anhydrous hydrogen chloride, sulfuric acid, and nitric acid, formic acid, acetic acid, oxalic acid, malonic acid, succinic acid, maleic acid, and fumaric acid. , organic carboxylic acids such as acrylic acid, citric acid, tartaric acid, glycolic acid, lactic acid, benzoic acid, organic sulfonic acids such as benzenesulfonic acid and toluenesulfonic acid, cation exchange such as gel-type cation exchange resins, porous cation exchange resins, etc. Examples include, but are not limited to, resins and complexes such as boron trifluoride and boron trifluoride etherate. Further, the amount of these acid catalysts used is preferably in the range of about 1 x 10 ^-5 to 10 ² weight ratio, particularly preferably in the range of about 0.01 to 1 weight ratio, based on the phenol aldehyde resin as the raw material.

In carrying out the method of the present invention, the purpose of the present invention can be fully achieved without using a reaction solvent, but it is usually desirable to use a suitable solvent. In this case, the solvent is not particularly limited, but a single or mixed solvent in which the phenol aldehyde resin and the phenols are dissolved under appropriate concentration and temperature conditions and in which only the bisphenols is difficult to dissolve is particularly preferably used. Examples of such solvents include water, alcohols such as methanol, ethanol, propanol, and butanol, ethers such as diethyl ether, dipropyl ether, and dibutyl ether, organic acids such as acetic acid, propionic acid, butyric acid, and methylene chloride. , dichloromethane, 1,2-dichloroethane, 1,2-dibromoethane, tricrene, chloroform, bromoform, carbon tetrachloride, halogenated hydrocarbons such as dichlorobenzene, hydrocarbons such as tetralin, toluene, benzene, cyclohexane, n-heptane, etc. etc., but the invention is not limited to these examples. Further, these solvents may be used alone or as a mixture. In addition, the ratio of the solvent used to the phenolaldehyde resin is preferably about 1 x 10 ^-3 to 10 ⁴ weight ratio, especially about
A weight ratio of 0.01 to 100 is preferred.

Next, the ratio of the phenol aldehyde resin as a reaction raw material to the phenols is preferably about 0.01 to 100 weight ratio, particularly about 0.3 to 50 weight ratio.

During the reaction of the method of the present invention, the reaction temperature is about -20
℃ to 150℃, especially about -5℃ to 100℃, and the reaction time is about 5 minutes to 72 hours, especially about 30 minutes to 24 hours.
A time range is preferred. In addition, under the above reaction conditions, after the reaction, the reaction mixture is cooled, the generated bisphenols are precipitated as crystals, and the residual liquid is removed by filtration etc. By reacting the reacted phenol aldehyde resin and repeating such operations, it is also possible to selectively convert substantially all of the raw material phenol aldehyde resin into bisphenols, and such operations are applicable to the present invention. This is particularly preferably carried out in the method.

In carrying out the method of the present invention, the reaction method is not particularly limited, and a batch method, a continuous method, a fixed bed method, or various other commonly used methods can be used.

Conventionally, when producing bisphenols through the condensation reaction of phenols and aldehydes, a large amount of phenolic aldehyde resin was produced as a by-product, and the production efficiency of bisphenols was not necessarily satisfactory. According to the method of the present invention, such a by-product phenolaldehyde resin can be converted into the target substance bisphenols with extremely high selectivity, which makes it possible to economically produce bisphenols. Not only does it bring about significant advantageous effects, but it also has the excellent feature that phenolic aldehyde resins, which generally have limited uses, can be easily converted into bisphenols, which are more useful.

The method of the present invention will be specifically explained below with reference to Examples.

Example 1 Commercially available phenol was placed in a four-necked flask equipped with a thermometer, reflux condenser, dropping funnel, and stirrer.
Add 94.1g (1.0mol), 400ml of tetrahydrofuran and 39.6g (0.9mol) of acetaldehyde,
The mixture was stirred and dissolved uniformly at room temperature. Next, 10.8 g (0.1 mol) of commercially available 36% hydrochloric acid was added dropwise using a dropping funnel over 30 minutes while stirring at room temperature, and the temperature was raised to 60° C. and the reaction was continued by stirring for an additional 5 hours. After this reaction, the reaction mixture was cooled to room temperature and poured into a large amount of chloroform to precipitate an extremely pale yellow-white phenolic acetaldehyde resin, which was further filtered to obtain 93 g of a phenolic acetaldehyde resin. As a result of analysis, this phenolic acetaldehyde resin has two phenolic
1.2% by weight of bisphenol ethane, which is a nuclear substance,
It contained 3.5% by weight of trinuclear bodies, 6.7% by weight of tetranuclear bodies, and 88.6% by weight of pentanuclear bodies or more.

Moreover, the number average molecular weight was 1450.

Next, the above phenolic acetaldehyde resin
Put 12.0g into a 100ml four-neck flask, add 18.8g of phenol and 4.0g of water, and heat at 60°C.
After stirring and dissolving the mixture, the mixture was cooled to 30°C. Next, add 5.4 g of commercially available 36% hydrochloric acid through the dropping funnel.
(0.05 mol) was added dropwise over 30 minutes, and the mixture was further stirred at room temperature for 6 hours to react. Further, as a result of further standing at room temperature for 30 hours, a slurry-like reaction mixture containing a large amount of white crystals was obtained, which was filtered to obtain 12 g of white crude crystals and 26.3 g of a filtrate. Gel permeation chromatography and Karl Fischer analysis of this crude crystal revealed that it contained 1.1 g of water, 4.1 g of phenol, 3.8 g of bisphenolethane, and a trinuclear substance containing three phenol nuclei.
It contained 1.0 g, 0.6 g of tetranuclear bodies, and 1.4 g of pentanuclear bodies. On the other hand, from the analysis results of the filtrate,
The filtrate also contained 0.6 g of bisphenol ethane. From the above results, it is clear that the amount of bisphenolethane contained in the phenolacetaldehyde resin raw material was 0.14 g before the reaction, but increased to 4.4 g after the reaction.

Example 2 188.2 g (2.0 g) of commercially available primary phenol was placed in a 300 ml three-necked flask equipped with a stirrer, thermometer, and dropping funnel.
mol) and 24.4 ml of water were stirred and dissolved at room temperature, resulting in a colorless and transparent solution. Next, add 26.9 g of commercially available first grade acetaldehyde to this three-necked flask at room temperature.
ml (0.48 mol), stir to dissolve, and then add 35 ml (0.48 mol).
36% hydrochloric acid via dropping funnel under stirring at °C.
As a result of dropping 9.1 ml (0.1 mol) little by little, a white-pink slurry solution was obtained. In this way, 35℃
After reacting with stirring for 3 hours, the mixture was cooled to room temperature and left for an additional 24 hours. After the reaction is complete, filter the slurry solution to obtain 88.7 g of white pink cake-like crude crystals.
was obtained, and analysis of this by Karl Fischer analysis and gel permeation chromatography revealed 6.6 g of water, 37.4 g of phenol, 36.5 g of bisphenol ethane, 5.0 g of a trinuclear body containing three phenol nuclei, and a tetranuclear body. It contained 2.6g and 0.6g of pentanuclear bodies or more. On the other hand, the weight of the filtrate from the filtration was 148 g, and as a result of analyzing it in the same manner as above, it was found that 32.1 g of water, 70.8 g of phenol, 12.2 g of bisphenol ethane, 18.9 g of trinuclear bodies, 11.2 g of tetranuclear bodies, It contained 2.8 g of pentanuclear bodies or more. From the above analysis results, the conversion rate of acetaldehyde was 100%.

Next, 1.12 (0.05 mol) of hydrogen chloride gas was blown into the filtrate after this reaction at room temperature, and as a result of standing for an additional 24 hours, a pink-white slurry solution was again obtained. This solution was filtered, and 60.5 g of white pink cake-like crude crystals were analyzed. As a result, water 5.5 g, phenol 21.0 g, bisphenol ethane 31.4 g,
It contained 1.8 g of nuclear bodies, 0.8 g of tetranuclear bodies, and no pentanuclear bodies or more were present. On the other hand, as a result of analyzing 87.8 g of filtrate, water 26.6 g, phenol 41.9 g, bisphenol ethane 11.4 g, trinuclear 6.1 g, tetranuclear 1.6 g,
It was 0.2g of pentanuclear bodies or more. As a result, the bisphenol ethane contained in the first reaction filtrate was 12.2 g, but by adding hydrogen chloride gas to this filtrate and performing the second reaction, The amount of bisphenolethane contained in the slurry reaction mixture increased to 42.8 g, and it is clear that the trinuclear or higher phenolic acetaldehyde resin was converted to 30.6 g of bisphenolethane.

Next, 1.12 (0.05 mol) of hydrogen chloride gas was blown into 87.8 g of the second reaction filtrate at room temperature and left to stand for 48 hours, thereby obtaining a white-pink slurry solution again. Analysis of this slurry solution revealed that it contained 26.4 g of water, 42.8 g of phenol, 13.3 g of bisphenol ethane, 4.1 g of trinuclear bodies, and 1.0 g of nuclear bodies, and no pentanuclear bodies or more were present. From this result, the bisphenol ethane contained in the filtrate after the second reaction was 11.4 g, while the amount of bisphenol ethane contained in the filtrate after the second reaction was 11.4 g.
The amount increased to 13.3g by the second reaction. That is,
The phenolic acetaldehyde resin having three or more nuclear bodies was further converted to bisphenolethane, and the phenolic acetaldehyde resin having five or more nuclear bodies no longer existed.

Example 3 In the same manner as in Example 1, 2.24 (0.1 mol) of hydrogen chloride gas was blown into a mixed solution of 94.1 g of phenol, 6.0 g of paraformaldehyde, and 10 ml of water, and after reacting at room temperature for 3 hours, the reaction mixture was analyzed. As a result, it contained 13.4 g of water, 64.5 g of phenol, 17.9 g of bisphenol F, 6.3 g of trinuclear, 2.8 g of tetranuclear, 5.2 g of pentanuclear or more, and 0.29 g of paraformaldehyde. Next, add more water to this mixture.
Add 10 ml of hydrogen chloride gas, then blow in 1.12 (0.05 mol) of hydrogen chloride gas under stirring at room temperature, and leave it as it is.
It was left to react for 15 hours. The analysis results of this reaction mixture showed that it contained 23.6 g of water, 55.3 g of phenol, 26.6 g of bisphenol F, 6.4 g of trinuclear bodies, 2.8 g of tetranuclear bodies, and 0.7 g of nuclear bodies. As a result,
All of the 0.29g of paraformaldehyde that remained during the reaction was reacted, and bisphenol F was reduced from 17.9g to 26.6g.
g, of which at least
6.8g was converted from phenol formaldehyde resin. Assuming that 0.29g of paraformaldehyde is completely converted to bisphenol F, the amount of bisphenol equivalent to this is
This is due to the fact that it is 1.9g.

Example 4 In the same manner as in Example 2, 35% formalin aqueous solution was used instead of paraformaldehyde, and 2.24 (3.6 g) of hydrogen chloride gas was blown into a mixture of 94.1 g of phenol, 17.2 g of formalin aqueous solution, and 0.5 ml of water.
As a result of reacting at room temperature for 3 hours, the reaction mixture became watery.
13.6g, phenol 62.7g, bisphenol F22.2
g, 8.9 g of trinuclear bodies, 2.9 g of tetranuclear bodies, and 1.3 g of pentanuclear bodies or more. Also, at this time, 100% of formaldehyde had been converted. Next, 10 ml of water was added to this reaction solution, and 2.24 mL of hydrogen chloride gas was blown into the solution while stirring at room temperature, and the solution was left to stand for 48 hours.
Afterwards, the reaction mixture was analyzed and found to have a water content of 23.5%.
g, phenol 61.7g, bisphenol F25.8g,
It contained 7.6 g of trinuclear bodies and 2.9 g of tetranuclear bodies, and no pentanuclear bodies or more were present. From this result, it is clear that 3.6 g of bisphenol F was produced from the phenol formaldehyde resin having three or more nuclear bodies.

Claims (1)

[Claims] 1. A method for selectively producing bisphenols, which comprises reacting a phenol aldehyde resin with a phenol in the presence of an acid catalyst.