JP7021560B2 - Method for manufacturing bisphenol and method for manufacturing polycarbonate resin - Google Patents

Description

The present invention relates to a method for producing bisphenol and a polycarbonate resin using bisphenol obtained by the method.
The bisphenol produced in the present invention is used as a resin raw material such as a polycarbonate resin, an epoxy resin, and an aromatic polyester resin, and as an additive such as a curing agent, a color developer, a fading inhibitor, and other bactericidal agents and antibacterial and antifungal agents. It is useful.

Bisphenol is useful as a raw material for polymer materials such as polycarbonate resin, epoxy resin, and aromatic polyester resin. Typical bisphenols include, for example, 2
, 2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-)
Methylphenyl) propane and the like are known (Patent Document 1). Among the methods for producing bisphenol, as a production method using sulfuric acid as a catalyst, for example, a production method using a mixture of hydrochloric acid and sulfuric acid as a catalyst (Patent Document 2) and a production method using sulfuric acid as a catalyst (Patent Document 3) are known. ing.

In the production method using sulfuric acid as a catalyst (Patent Document 3), it is known that a reaction for producing bisphenol is carried out after adding sulfuric acid, phenol, a cyclic ketone and a thiol into a reactor to make them uniform.

Japanese Patent Application Laid-Open No. 62-138443 Japanese Unexamined Patent Publication No. 2014-40376 JP 2015-51935

However, when the present inventor produced bisphenol by the method described in Patent Document 3, it was found that there is a problem that thiol is remarkably oxidatively decomposed to generate disulfide and the yield of bisphenol is remarkably lowered. Therefore, the present invention suppresses the oxidative decomposition of the thiol without using hydrogen chloride gas or hydrochloric acid, which is highly corrosive and requires dedicated equipment, and is simple, efficient, stable, and industrially. It is an object of the present invention to provide an advantageous method for producing bisphenol.

The present inventor has made diligent studies to solve the above problems. As a result, by reacting thiol with a ketone or aldehyde in advance to generate bisphenol, the reaction temperature is preferably further reduced to 50 ° C. or lower, and the concentration of sulfuric acid to be used is preferably 50% by weight or more. By reducing the weight to less than%, the invention of a simple and efficient method for producing industrially advantageous bisphenol was completed.

That is, the gist of the present invention lies in the following [1] to [3].
[1] A method for producing bisphenol, which comprises a step of producing and reacting aromatic alcohol and a ketone or aldehyde in the presence of sulfuric acid and thiol, obtained by mixing the thiol with the ketone or aldehyde. A method for producing bisphenol, which comprises mixing the mixture with the aromatic alcohol to produce and react the bisphenol.
[2] The method for producing bisphenol according to [1], wherein the reaction temperature of the production reaction is 50 ° C. or lower.
[3] A method for producing a polycarbonate resin, which comprises producing bisphenol by the method for producing bisphenol according to [1] or [2], and producing a polycarbonate resin using the bisphenol.

According to the present invention, by mixing thiol with a ketone or aldehyde in advance and then reacting the thiol, it is possible to suppress the oxidative decomposition of the thiol, and the yield of the target bisphenol is improved. As described above, by suppressing the oxidative decomposition of thiol, various bisphenols can be produced easily and efficiently in an industrially advantageous manner.

Hereinafter, embodiments of the method for producing bisphenol of the present invention will be described in detail. In the method for producing bisphenol of the present invention, bisphenol is produced by condensing an aromatic alcohol with a ketone or aldehyde using sulfuric acid as a catalyst and thiol as a co-catalyst. It is characterized in that the obtained mixture is mixed with the aromatic alcohol to produce and react the bisphenol.
The reaction for producing bisphenol is carried out according to the reaction formula (1) shown below.

(In the formula, R ¹ to R ⁶ independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, and an aryl group, respectively.)

[Bisphenol]
The bisphenol produced in the present invention is usually a compound represented by the following general formula (2).

Examples of R ¹ to R ⁴ include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group and the like independently, and examples thereof include a proton; a halogen atom such as a fluoro group, a chloro group, a bromo group and an iodine group. Methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-
Chain alkyl groups such as hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group; methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, i-butoxy group, t-butoxy group, n-pentyloxy group, i-pentyloxy group, n-hexyloxy group, n-heptyloxy group,
alkoxy groups such as n-octyloxy group, n-nonyloxy group, n-decyloxy group, n-undecyloxy group, n-dodecyloxy group; cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cyclo Cyclic alkyl groups such as petit group, cyclooctyl group and cyclododecyl group; aryl groups such as benzyl group, phenyl group, trill group and 2,6-dimethylphenyl group can be mentioned. Of these, R ² and R ³ are preferably protons because the condensation reaction does not easily proceed if they are sterically bulky.

Examples of R ⁵ and R ⁶ include a hydrogen atom, an alkyl group, an alkoxy group, an aryl group and the like independently of each other, and examples thereof include a proton, a methyl group, an ethyl group, an n-propyl group, an i-propyl group and an n-. Butyl group, i-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group, n-nonyl group, Chain alkyl groups such as n-decyl group, n-undecyl group, n-dodecyl group; methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, i-butoxy group, t-butoxy Group, n-pentyloxy group, i-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, n-nonyloxy group, n-decyloxy group, n-undecyloxy group, n -Ekoxy group such as dodecyloxy group; cyclic alkyl group such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclododecyl group; benzyl group, phenyl group,
Examples thereof include an aryl group such as a trill group and a 2,6-dimethylphenyl group.

R ⁵ and R ⁶ may be bonded or crosslinked with each other between the two groups, eg, cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, 3, 3, 5
-Trimethylcyclohexylidene, cycloheptylidene, cyclooctylidene, cyclononilidene, cyclodecylidene, cycloundecylidene, cyclododecylidene, fluorenilidene, xanthonidene, thioxanthonilidene and the like.

[Aromatic alcohol]
The aromatic alcohol used in the present invention is usually a compound represented by the following general formula (3).

Examples of the substituents of R ¹ to R ⁴ include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group and the like independently, and examples thereof include a proton, a fluoro group, a chloro group, a bromo group and an iodo group. Halogen atoms: methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group,
Chain alkyl groups such as n-undecyl group and n-dodecyl group; methoxy group, ethoxy group, n-
Propoxy group, i-propoxy group, n-butoxy group, i-butoxy group, t-butoxy group,
n-pentyloxy group, i-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, n-nonyloxy group, n-decyloxy group, n-undecyloxy group, n-dodecyl An alkoxy group such as an oxy group; a cyclic alkyl group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclododecyl group; a benzyl group, a phenyl group, a trill group, 2 , 6-Dimethylphenyl group and other aryl groups. Of these, R ² and R ³ are preferably protons because the condensation reaction does not easily proceed if they are sterically bulky.

[Ketones and aldehydes]
The ketone and aldehyde used in the present invention are usually compounds represented by the following general formula (4).

Examples of R ⁵ and R ⁶ include a hydrogen atom, an alkyl group, an alkoxy group, an aryl group and the like independently of each other, and examples thereof include a proton; a methyl group, an ethyl group, an n-propyl group, an i-propyl group and an n-. Butyl group, i-butyl group, t-butyl group, n-pentyl group, i-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group, n-nonyl group, Chain alkyl group of n-decyl group, n-undecyl group, n-dodecyl group; methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, i-butoxy group, t-butoxy group , N-pentyloxy group, i-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, n-nonyloxy group, n-decyloxy group, n-undecyloxy group, n- An alkoxy group such as a dodecyloxy group; a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group,
Examples thereof include a cyclic alkyl group such as a cyclooctyl group and a cyclododecyl group, an aryl group such as a benzyl group, a phenyl group, a tolyl group, and a 2,6-dimethylphenyl group.

R ⁵ and R ⁶ may be bonded or crosslinked with each other between the two groups, eg, cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, 3, 3, 5
-Trimethylcyclohexylidene, cycloheptylidene, cyclooctylidene, cyclononilidene, cyclodecylidene, cycloundecylidene, cyclododecylidene, fluorenilidene, xanthonidene, thioxanthonilidene and the like.

In the reaction of condensing an aromatic alcohol with a ketone or an aldehyde, the molar ratio of the aromatic alcohol to the ketone or the aldehyde is such that the amount of the ketone or the aldehyde increases when the amount is small, and the amount of the aromatic alcohol is lost when the amount is large. from these things,
The molar ratio of the aromatic alcohol to the ketone or aldehyde is preferably 1.5 or more, more preferably 1.6 or more, still more preferably 1.7 or more, and more preferably.
It is 15 or less, more preferably 10 or less, still more preferably 8 or less.
As a method for supplying ketones and aldehydes, a method of supplying them all at once and a method of supplying them in divided portions can be used. The method of supplying in divided portions is preferable.

[Sulfuric acid]
Concentrated sulfuric acid can be used as the sulfuric acid used in the present invention. However, if the concentration of the sulfuric acid is high, there is a risk of promoting the increase in the amount of ketone or aldehyde and the dehydration dimerization of the fatty alcohol used as appropriate, and it is possible to deteriorate the thiol and sulfonate the produced bisphenol. There is sex. Further, when the concentration of sulfuric acid used is low, the reaction time becomes long and the efficiency of bisphenol production tends to be inferior. Therefore, the concentration of sulfuric acid used is preferably 50% by weight or more, more preferably 60% by weight or more. Further, when the sulfuric acid concentration is high (that is, the concentration of water in the sulfuric acid is low), and the amount of acetone and an appropriately used solvent (details will be described later) is small with respect to the amount of water contained in the sulfuric acid. Acetone is abundant in mesityl oxide (dimerization product) and the like, and dehydration of the aliphatic alcohol used as appropriate 2
The concentration of sulfuric acid used is preferably 95% by weight or less, more preferably 90% by weight or less, because it may promote quantification and oxidatively decompose thiols. On the other hand, when the sulfuric acid concentration is high (that is, the concentration of water in the sulfuric acid is low) and the amount of acetone and an appropriately used solvent (details will be described later) is large relative to the amount of water contained in the sulfuric acid. Since acetone can suppress the increase in the amount of mesityl oxide (dimerization product), the dehydration dimerization of the aliphatic alcohol used as appropriate, and the oxidative decomposition of thiol, the concentration of sulfuric acid used in the above. Is preferably 90% by weight or more, more preferably 95% by weight or more.

In the present invention, when the molar ratio of sulfuric acid to ketone or aldehyde is small, sulfuric acid tends to be diluted by water produced as a by-product during the condensation reaction and a reaction time tends to be required. Tend. From these facts, the molar ratio of sulfuric acid to the ketone or aldehyde is preferably 0.01 or more, more preferably 0.05 or more, still more preferably 0.1 or more, and 10 or less, more preferably 8 or less. , More preferably 5 or less.

[Fatty alcohol]
In the present invention, fatty alcohols can be used. Examples of the aliphatic alcohol used include methanol, ethanol, n-propanol, i-propanol, and n.
-Butanol, i-butanol, t-butanol, n-pentanol, i-pentanol, n-hexanol, n-heptanol, n-octanol, n-nonanol, n-decanol, n-undecanol, n-dodecanol, ethylene Examples thereof include alkyl alcohols having 1 to 12 carbon atoms such as glycol, diethylene glycol, and triethylene glycol. The fatty alcohol has an increased lipophilicity as the number of carbon atoms increases, and tends to be difficult to mix with sulfuric acid and to obtain monoalkyl sulfate. Therefore, an alkyl alcohol having 8 or less carbon atoms is preferable.

In the present invention, the aliphatic alcohol can be mixed with sulfuric acid to prepare a monoalkyl sulfate and used. When the molar ratio of the fatty alcohol to sulfuric acid is low, the amount of monoalkyl sulfate generated is small and reaction time is required, and when the ratio is high, the sulfuric acid concentration is lowered. From these facts, the molar ratio of the aliphatic alcohol to sulfuric acid is preferably 0.01 or more, more preferably 0.05 or more, still more preferably 0.1 or more, and preferably 10 or less, more preferably. It is 5 or less, more preferably 3 or less.

[Thiol]
Examples of the thiol used in the present invention include mercaptocarboxylic acids such as mercaptoacetic acid, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid and 4-mercaptobutyric acid, methyl mercaptan, ethyl mercaptan, propyl mercaptan and butyl mercaptan. , Pentyl mercaptan, hexyl mercaptan, heptyl mercaptan, octyl mercaptan, nonyl mercaptan, decyl mercaptan, undecyl mercaptan, dodecyl mercaptan.

When the molar ratio of the thiol to the ketone or aldehyde is small, the effect of improving selectivity tends to be insufficient, and when it is large, it tends to be mixed with bisphenol and the quality tends to deteriorate. From these facts, the molar ratio of the thiol to the ketone or aldehyde is preferably 0.001 or more, more preferably 0.005 or more, still more preferably 0.01 or more, and preferably 1 or less. It is preferably 0.5 or less, more preferably 0.1 or less.

In the production method of the present invention, the thiol is premixed with a ketone or an aldehyde and then reacted. As a method for supplying a thiol and a ketone or an aldehyde, a ketone or an aldehyde may be mixed with the thiol, or a thiol may be mixed with the ketone or the aldehyde.
Further, in the production method of the present invention, a mixture of thiol and a ketone or aldehyde is mixed with an aromatic alcohol to carry out a reaction for producing bisphenol. The method for mixing the mixture and the aromatic alcohol is not particularly limited, but supplying the mixture to the aromatic alcohol is preferable from the viewpoint of avoiding self-condensation of the ketone or aldehyde.
Further, in the method of mixing a mixed solution of thiol and a ketone or an aldehyde and sulfuric acid, sulfuric acid may be mixed with the mixed solution, or the mixed solution may be mixed with sulfuric acid, but the mixed solution may be mixed with sulfuric acid. Is preferable. Further, it is more preferable to supply sulfuric acid and an aromatic alcohol to the reaction vessel and then supply the mixed solution to the reaction vessel for mixing.

[solvent]
In the present invention, the reaction for producing bisphenol may be carried out in the presence of a solvent such as toluene or xylene. Further, the solvent used for producing bisphenol can be recovered and purified by distillation or the like and reused.
Further, a large amount of aromatic alcohol may be used instead of the solvent without using a solvent, and the unreacted aromatic alcohol becomes a loss, so that it can be recovered and purified by distillation or the like and reused. Is.

[Bisphenol formation reaction]
In the present invention, the bisphenol formation reaction is a condensation reaction, but when the reaction temperature of the formation reaction is high, the oxidative decomposition of thiol tends to proceed, and when the temperature is low, the time required for the reaction tends to be long. Therefore, it is preferably 0 ° C. or higher and 50 ° C. or lower.
The reaction time of the production reaction is preferably 30 hours or less, more preferably 25 hours or less, still more preferably 20 hours or less because there is a risk that the produced bisphenol may be decomposed if the reaction time is long. It is possible to stop the reaction by adding water equal to or more than the amount of sulfuric acid used to reduce the sulfuric acid concentration.

[Purification method]
Purification of the bisphenol obtained by the production reaction in the present invention can be carried out by a conventional method. For example, it can be purified by a simple means such as crystallization or column chromatography. Specifically, after the condensation reaction, the organic phase obtained by separating the reaction solution is washed with water or saline, and if necessary, neutralized and washed with sodium bicarbonate water or the like. Then, the washed organic phase is cooled and crystallized. When a large amount of aromatic alcohol is used, excess aromatic alcohol is distilled off by distillation before crystallization and then crystallization is performed.

[Use of bisphenol]
The bisphenol of the present invention is a polyether resin, a polyester resin, a polyarylate resin, a polycarbonate resin, a polyurethane resin, which are used for various purposes such as optical materials, recording materials, insulating materials, transparent materials, electronic materials, adhesive materials, and heat resistant materials. Components, curing agents, additives or precursors thereof such as various thermoplastic resins such as acrylic resin, various thermosetting resins such as epoxy resin, unsaturated polyester resin, phenol resin, polybenzoxazine resin and cyanate resin. It can be used as such. It is also useful as an additive such as a color developer such as a heat-sensitive recording material, a fading inhibitor, a bactericide, and an antibacterial and antifungal agent.
Of these, it is preferable to use it as a raw material (monomer) for a thermoplastic resin or a thermosetting resin, and it is more preferable to use it as a raw material for a polycarbonate resin or an epoxy resin, because it can impart good mechanical properties. It is also preferable to use it as a color developer, and it is more preferable to use it in combination with a leuco dye and a color change temperature adjusting agent.

[Manufacturing method of polycarbonate resin]
The polycarbonate resin, which is one of the uses of the bisphenol produced in the present invention, comprises bisphenol produced by the above method and a carbonic acid diester such as diphenyl carbonate.
For example, it can be produced by a transesterification reaction in the presence of an alkali metal compound and / or an alkaline earth metal compound. The transesterification reaction can be carried out by appropriately selecting a known method, and an example using the bisphenol and diphenyl carbonate as raw materials will be described below.

In the above method for producing a polycarbonate resin, it is preferable to use an excess amount of diphenyl carbonate with respect to the bisphenol. The amount of diphenyl carbonate used for the bisphenol is preferably large in that the produced polycarbonate resin has few terminal hydroxyl groups and is excellent in thermal stability of the polymer, and the transesterification reaction rate is high and the desired molecular weight is obtained. It is preferable that the amount is small in terms of easy production of the polycarbonate resin. from these things,
The amount of diphenyl carbonate used per 1 mol of bisphenol is usually 1.001 mol or more, preferably 1.002 mol or more, and usually 1.3 mol or less, preferably 1.2 mol.
It is less than a mole.

As a method for supplying the raw materials, the bisphenol and diphenyl carbonate can be supplied in solid form, but it is preferable to supply one or both of them in a liquid state by melting them.
When producing a polycarbonate resin by transesterification reaction of diphenyl carbonate and bisphenol, a catalyst is usually used. In the above method for producing a polycarbonate resin, it is preferable to use an alkali metal compound and / or an alkaline earth metal compound as the transesterification catalyst. These may be used alone or in any combination and ratio of two or more. Practically, alkali metal compounds are desirable.

The amount of catalyst used for 1 mol of bisphenol or diphenyl carbonate is usually 0.0.
It is 5 μmol or more, preferably 0.08 μmol or more, more preferably 0.10 μmol or more, and usually 100 μmol or less, preferably 50 μmol or less, still more preferably 20.
It is less than μmol.
When the amount of the catalyst used is within the above range, the polymerization activity required for producing a polycarbonate resin having a desired molecular weight can be easily obtained, the polymer hue is excellent, and excessive polymer branching does not proceed. It is easy to obtain a polycarbonate resin with excellent fluidity during molding.

In order to produce the polycarbonate resin by the above method, it is preferable that both of the above raw materials are continuously supplied to the raw material mixing tank, and the obtained mixture and the transesterification catalyst are continuously supplied to the polymerization tank.
In the production of the polycarbonate resin by the transesterification method, usually, both raw materials supplied to the raw material mixing tank are uniformly stirred and then supplied to the polymerization tank to which the catalyst is added, and the polymer is produced as a resin.

[Polycarbonate resin]
As described above, the bisphenol obtained by the production method of the present invention has a very high purity.
Since there is little coloring, a high-purity polycarbonate resin can be obtained by polycondensing bisphenol and diphenyl carbonate obtained by the production method of the present invention in the presence of a transesterification catalyst.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples as long as the gist of the present invention is not exceeded.

[Raw materials and reagents]
Orthocresol, acetone, methanol, dodecyl mercaptan, toluene, sulfuric acid,
Acetonitrile, acetic acid, ammonium acetate, sodium hydroxide, cesium carbonate and sodium hydrogen carbonate used special grade reagents manufactured by Wako Pure Chemical Industries, Ltd.
As diphenyl carbonate, a product manufactured by Mitsubishi Chemical Corporation was used.
Didodecyl disulfide is the Angel International Limit
A reagent manufactured by ed was used.

[analysis]
The composition analysis of the bisphenol reaction was performed by high performance liquid chromatography under the following procedure and conditions.
Equipment: LC-2010A manufactured by Shimadzu Corporation, ImtactScherzoSM-C18
3 μm 150 mm × 4.6 mm ID. Low pressure gradient method. Analysis temperature 40 ° C. Eluent composition: Solution A Ammonium acetate: Acetic acid: Dechlorinated water = 3.000 g: 1 ml: 1 liter solution. Liquid B Ammonium acetate: Acetic acid: Acetonitrile = 1.500 g: 1 ml: 900 ml solution. When the analysis time is 0 minutes, liquid A: liquid B = 60:40 (volume ratio,
The same applies below. ) Gradually change the eluent composition to solution A: solution B = 90:10 for analysis time 0 to 25 minutes, maintain solution A: solution B = 90:10 for analysis time 25 to 30 minutes, flow rate 0.8 Milliliter /
Analyzed in minutes. The detection wavelength was 280 nm.

For the reaction yield (mol%) based on acetone according to the present invention, the molar amount of bisphenol contained in the reaction solution is calculated from the analytical value of bisphenol obtained by high performance liquid chromatography, and the molar amount of the bisphenol ÷ the raw material. It was calculated by the molar amount of acetone × 100%.
Analysis of dodecyl mercaptan and dodecyl disulfide was performed by gas chromatography under the following procedure and conditions. The device used was "GC-17A" manufactured by Shimadzu Corporation. As the column, "DB-1" manufactured by Agilent Technologies (inner diameter 0.53 mm, column length 30 m, film thickness 1 μm) was used. The carrier gas is helium, and the flow rate is 5.
The linear velocity was 58 cm ³ , and the linear velocity was 47.4 cm per second. The inlet temperature is 250 ° C and the detector temperature is 28.
It was set to 0 ° C. The temperature rise pattern of the column was first held at 150 ° C. for 5 minutes and then 13 ° C. per minute.
The temperature was raised to 295 ° C. and held at 295 ° C. for 15 minutes for analysis.

The residual amount of dodecyl mercaptan is calculated by calculating the weight of dodecyl mercaptan contained in the reaction solution from the analytical value of dodecyl mercaptan obtained by gas chromatography, and calculating the weight of the dodecyl mercaptan ÷ the weight of the raw material dodecyl mercaptan × 100%. did.
For the production rate of didodecyl disulfide, the amount of substance of didodecyl disulfide contained in the reaction solution is calculated from the analytical value of didodecyl disulfide obtained by gas chromatography, and the amount of substance of the didodecyl disulfide × 2 ÷ raw material dodecyl. Amount of substance of mercaptan x 10
Calculated at 0%.

(Viscosity average molecular weight)
Viscosity average molecular weight (Mv) is determined by dissolving a polycarbonate resin in methylene chloride (concentration 6.
The specific viscosity (ηsp) at 20 ° C. was measured using a Ubbelohde viscous tube at 0 g / L), and the viscosity average molecular weight (Mv) was calculated by the following formula.
ηsp / C = [η] (1 + 0.28ηsp)
[η] = 1.23 × 10 ^-4 Mv ^0.83

(Concentration of terminal hydroxyl group of polycarbonate resin)
The terminal hydroxyl group concentration (OH) concentration of the polycarbonate resin is the titanium tetrachloride / acetic acid method (Ma).
chromol. Chem. It was measured by colorimetric quantification in accordance with 88,215 (1965)).

(Pellet YI)
The pellet YI (transparency of the polycarbonate resin) was evaluated by measuring the YI value (yellowness index value) in the reflected light of the polycarbonate resin pellet in accordance with ASTM D1925. A spectrocolorimeter CM-5 manufactured by Konica Minolta Co., Ltd. was used as an apparatus, and a measurement diameter of 30 mm and SCE were selected as measurement conditions. Fit the calibration glass CM-A212 for petri dish measurement into the measurement section, cover it with the zero calibration box CM-A124, and perform zero calibration.
Subsequently, white calibration was performed using the built-in white calibration plate. Next, the white calibration plate CM-A210
L * is 99.40 ± 0.05, a * is 0.03 ± 0.01, b * is -0.43 ± 0.01, and YI is -0.58 ± 0. It was confirmed that it was 01. The pellets were measured by filling the pellets in a cylindrical glass container having an inner diameter of 30 mm and a height of 50 mm to a depth of about 40 mm. The operation of taking out the pellets from the glass container and then performing the measurement again was repeated twice, and the average value of the measured values of a total of three times was used.

Example 1
In a full jacket type 1 liter separable flask equipped with a thermometer, a stirrer and a 500 ml dropping funnel, 5 g (0.16 mol) of methanol, 180 g (1.66 mol) of orthocresol, 56 g of toluene under a nitrogen atmosphere. After adding, 100 g of 80% by weight sulfuric acid was slowly supplied. 39 g (0.67 mol) of acetone and 7.5 (0.04 mol) g of dodecyl mercaptan were supplied to the dropping funnel and mixed to obtain a mixed solution. The mixed solution was slowly added dropwise to the mixed solution of methanol, orthocresol, toluene, and sulfuric acid in a separable flask over 30 minutes using the dropping funnel. This reaction solution was reacted at 40 ° C. for 1 hour. After completion of the reaction, 100 g of toluene and 100 dechlorinated water
g was supplied and the temperature was raised to 80 ° C. After reaching 80 ° C., the mixture was allowed to stand to confirm that the substance precipitated during the reaction was dissolved in the organic phase and the aqueous phase, and then the lower aqueous phase was extracted. Then, a saturated sodium hydrogen carbonate solution was added to the obtained organic phase to neutralize it, and it was confirmed that the pH of the lower aqueous phase became 9 or more. After extracting the lower aqueous phase, dechlorinated water is added to the obtained organic phase for 10
Stir for minutes. After stirring, the mixture was allowed to stand and the aqueous phase was extracted. Take out a part of the obtained organic phase and take it out.
When the amount of 2,2-bis (4-hydroxy-3-methylphenyl) propane (hereinafter referred to as bisphenol C) produced by high performance liquid chromatography was confirmed, the reaction yield based on acetone was 83 mol%. rice field. Moreover, when the residual amount of dodecyl mercaptan was confirmed by gas chromatography, it was 62%. Furthermore, the production rate of didodecyl disulfide was 31 mol%.

Comparative Example 1
In a full jacket type 1 liter separable flask equipped with a thermometer, a stirrer and a 500 ml dropping funnel, 5 g (0.16 mol) of methanol, 180 g (1.66 mol) of orthocresol and 56 g of toluene under a nitrogen atmosphere. , Dodecyl mercaptan 7.5 (
After adding 0.04 mol) g, 100 g of 80% by weight sulfuric acid was slowly supplied. 39 g (0.67 mol) of acetone was supplied to the dropping funnel, and the acetone was slowly added to the dropping funnel over 30 minutes over 30 minutes with methanol, orthocresol, toluene, dodecyl mercaptan and dodecyl mercaptan in a separable flask. , Dropped into a mixed solution of sulfuric acid and supplied. This reaction solution was reacted at 40 ° C. for 1 hour. After completion of the reaction, 100 g of toluene and 100 g of dechlorinated water
Was supplied and the temperature was raised to 80 ° C. After reaching 80 ° C., the mixture was allowed to stand to confirm that the substance precipitated during the reaction was dissolved in the organic phase and the aqueous phase, and then the lower aqueous phase was extracted. Then, a saturated sodium hydrogen carbonate solution was added to the obtained organic phase to neutralize it, and it was confirmed that the pH of the lower aqueous phase became 9 or more. After extracting the aqueous phase of the lower layer, a part of the obtained organic phase was taken out, and 2,2-bis (4-hydroxy-3-methylphenyl) produced by high performance liquid chromatography was taken out.
When the amount of propane was confirmed, the reaction yield based on acetone was 63 mol%. again,
When the residual amount of dodecyl mercaptan was confirmed by gas chromatography, it was 27%. Furthermore, the production rate of didodecyl disulfide was 55 mol%.

For Example 1 and Comparative Example 1, the residual amount of dodecyl mercaptan and 2,2-bis (4-).
The amounts of hydroxy-3-methylphenyl) propane are summarized in Table 1. As a result, by mixing dodecyl mercaptan and acetone in advance and then reacting, the oxidative decomposition of dodecyl mercaptan is suppressed, and the reaction yield of 2,2-bis (4-hydroxy-3-methylphenyl) propane (bisphenol C) is suppressed. It turned out that the rate improved.

Example 2
100 g (0.39 mol) of bisphenol C and 86.5 g (0.4 mol) of diphenyl carbonate obtained in Example 1 were placed in a glass reaction vessel having an internal volume of 150 mL equipped with a stirrer and a distillate.
And 479 μL of a 400 mass ppm cesium carbonate aqueous solution was added. The operation of reducing the pressure of the glass reaction vessel to about 100 Pa and then restoring the pressure to atmospheric pressure with nitrogen was repeated three times to replace the inside of the reaction vessel with nitrogen. Then, the reaction vessel was immersed in an oil bath at 200 ° C. to dissolve the contents. The rotation speed of the stirrer is set to 100 times per minute, and the pressure in the reaction vessel is increased by absolute pressure over 40 minutes while distilling off the phenol produced by the oligomerization reaction of bisphenol C and diphenyl carbonate in the reaction vessel. The pressure was reduced from 101.3 kPa to 13.3 kPa. Subsequently, the pressure in the reaction vessel was maintained at 13.3 kPa, and the phenol was further distilled off for 80 minutes.
A transesterification reaction was carried out. After that, the temperature outside the reaction vessel was raised to 250 ° C., and 40
The pressure in the reaction vessel was reduced from 13.3 kPa to 399 Pa in absolute pressure over a minute, and the distilled phenol was removed from the system. Then, the external temperature of the reaction vessel was raised to 280 ° C., the absolute pressure of the reaction vessel was reduced to 30 Pa, and the polycondensation reaction was carried out. The polycondensation reaction was terminated when the stirrer in the reaction tank became a predetermined stirring power. Next, the reaction vessel was repressurized to 101.3 kPa with nitrogen at an absolute pressure, and then the pressure was increased to 0.2 MPa with a gauge pressure, and polycarbonate was extracted from the bottom of the reaction vessel in a strand shape to obtain a strand-shaped polycarbonate resin. Then, the strands were pelletized using a rotary cutter to obtain a pellet-shaped polycarbonate resin.

The viscosity average molecular weight (Mv) of the polycarbonate was 25,000. Also pellet Y
I was 8.0.

Claims (2)

A method for producing bisphenol, which comprises a step of producing and reacting an aromatic alcohol with a ketone or aldehyde in the presence of sulfuric acid and thiol, wherein the thiol is mixed with the ketone or aldehyde, and the obtained mixture is obtained. It is characterized in that the bisphenol is produced and reacted by mixing with an aromatic alcohol .
A method for producing bisphenol , wherein the reaction temperature of the production reaction is 50 ° C. or lower . A method for producing a polycarbonate resin, which comprises producing bisphenol by the method for producing bisphenol according to claim 1 , and producing a polycarbonate resin using the bisphenol.