JP7021561B2 - Method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane and method for producing polycarbonate resin - Google Patents

Description

The present invention is a method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane and a polycarbonate using 2,2-bis (4-hydroxy-3-methylphenyl) propane obtained by the production method. Regarding the method of manufacturing a resin.
2,2-Bis (4-hydroxy-3-methylphenyl) produced by the production method of the present invention.
Propane is useful 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.

Bisphenol is useful as a raw material for polymer materials such as polymer bonate resins, epoxy resins, and aromatic polyester resins. 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). Examples of the production method include a production method using hydrogen chloride gas as a catalyst (Patent Document 1), a production method using hydrochloric acid as a catalyst (Patent Document 2), and a production method using a mixture of hydrochloric acid and sulfuric acid as a catalyst (Patent Document 3). Are known.

It is known that a reaction solvent such as toluene is used in the method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane catalyzed by a mixture of hydrochloric acid and sulfuric acid. In addition, since hydrogen chloride gas, which is highly corrosive, volatilizes when hydrochloric acid is used as a catalyst in the production method, dedicated equipment is required when it is carried out industrially.

Japanese Patent Application Laid-Open No. 62-138443 Japanese Patent Application Laid-Open No. 2008-214248 Japanese Unexamined Patent Publication No. 2014-40376

However, when the present inventors produced 2,2-bis (4-hydroxy-3-methylphenyl) propane by the method described in Patent Document 3, a large amount of mesityl oxide, which is a dimerized product of acetone, was produced. It was found that there is a problem that the selectivity of 2,2-bis (4-hydroxy-3-methylphenyl) propane is lowered and the reaction solution is solidified to cause poor mixing and further reaction time is required. did. Therefore, the present invention suppresses the formation of mesityl oxide, which is a dimerized product of acetone as a raw material, without using hydrochloric acid, which is highly corrosive and requires dedicated equipment, and further, the fluidity of the reaction solution. It is an object of the present invention to provide a simple and efficient method for stably producing 2,2-bis (4-hydroxy-3-methylphenyl) propane by improving the above conditions and shortening the time required for the reaction. ..

As a result of diligent studies to solve the above problems, the present inventors mixed orthocresol and acetone, used monoalkyl sulfate as a catalyst, mixed the solvent with acetone in advance, and then supplied the reactor. , 2-Bis (4-hydroxy-3-methylphenyl) Propane production method, preferably 2,2-Bis (4) in which the mixing temperature of orthocresol and acetone is controlled.
The present invention has found a simple, efficient, and industrially advantageous method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane by a method for producing -hydroxy-3-methylphenyl) propane. Has been completed.

That is, the gist of the present invention lies in the following [1] to [9].
[1] A method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane from orthocresol and acetone.
The orthocresol, the acetone, and the monoalkyl sulfate are mixed in a reactor and 2
Includes steps to produce 2-bis (4-hydroxy-3-methylphenyl) propane.
A method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane, which comprises premixing the acetone with a solvent and then supplying the mixture to the reactor and mixing with the orthocresol.
[2] The 2,2-bis (4-hydroxy-3-methyl) according to [1], wherein the orthocresol and the monoalkyl sulfate are mixed in advance and then mixed with a mixture of acetone and a solvent. Phenyl) A method for producing propane.
[3] The temperature at which the mixture of acetone and the solvent is mixed with the mixture of monoalkyl sulfate and orthocresol in the reactor is 25 ° C. or higher and 40 ° C. or lower [2].
] The method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane according to.
[4] The method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane according to any one of [1] to [3], wherein the solvent is an aromatic hydrocarbon.
[5] The 2,2-bis (4-hydroxy-3) according to any one of [1] to [4], wherein the monoalkyl sulfate comprises a step of producing from sulfuric acid and an aliphatic alcohol. -
Methylphenyl) Propane production method.
[6] The 2,2-bis (4-hydroxy-3-methylphenyl) according to [5], wherein the molar ratio of the aliphatic alcohol to the sulfuric acid is 0.001 or more and 10 or less. How to make propane.
[7] The step according to any one of [1] to [6], wherein the step of producing 2,2-bis (4-hydroxy-3-methylphenyl) propane is carried out in the presence of thiol. 2,2-Bis (4-hydroxy-3-methylphenyl) propane production method.
[8] The 2,2-bis (4-hydroxy-3-methylphenyl) according to [7], wherein the thiol and the acetone are mixed, and then the monoalkyl sulfate is mixed.
Propane manufacturing method.
[9] To produce 2,2-bis (4-hydroxy-3-methylphenyl) propane by the production method according to any one of [1] to [8], and to produce a polycarbonate resin using this. A characteristic method for producing a polycarbonate resin.

According to the present invention, by premixing the solvent with acetone and then supplying it to the reactor, the reaction time is shortened and the target 2,2-bis (4-hydroxy-3-methylphenyl) propane is high. It can be produced with a reaction yield. Moreover, in this way, a few are simple and efficient.
-Bis (4-hydroxy-3-methylphenyl) propane can be stably produced.

Hereinafter, embodiments of the method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane (hereinafter, may be referred to as bisphenol C) of the present invention will be described in detail.
The present invention is a method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane from orthocresol and acetone, wherein the orthocresol, the acetone, and the like.
And monoalkyl sulfate are mixed in a reactor to produce 2,2-bis (4-hydroxy-3-methylphenyl) propane.
The acetone is premixed with a solvent and then supplied to the reactor to be mixed with the orthocresol.

That is, in the method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane of the present invention, a solvent is previously mixed with acetone using monoalkyl sulfate as a catalyst, and then supplied to the reactor, and the acetone is supplied. And orthocresol are condensed to produce 2,2-bis (4-hydroxy-3-methylphenyl) propane.
The reaction of 2,2-bis (4-hydroxy-3-methylphenyl) propane is carried out according to the reaction formula (1) shown below.

[Orthocresol and Acetone]
In the production method of the present invention, the supply ratio (molar ratio) of orthocresol to acetone
Can be used in excess with respect to acetone. However, when the supply ratio (molar ratio) of orthocresol to acetone is small, acetone is mesityl oxide (mole ratio).
It will be abundant in a dimerized product), and if it is abundant, orthocresol will be lost unreacted. From these facts, the supply ratio (molar ratio) of orthocresol to acetone is preferably 1.5 or more, more preferably 1.6 or more, still more preferably 1.7 or more, and preferably 15 or less. It is more preferably 10 or less, still more preferably 8 or less.

As a method of mixing orthocresol and acetone, a method of supplying orthocresol to the reactor in advance and then dropping acetone to mix, or a method of supplying acetone to the reactor in advance and then dropping orthocresol to be mixed is used. Is possible. However, in the method of supplying acetone to the reactor in advance and then dropping orthocresol and mixing, the amount of acetone increases and the selectivity of 2,2-bis (4-hydroxy-3-methylphenyl) propane decreases. Since there is a tendency, a method in which orthocresol is supplied to the reactor in advance and then acetone is added dropwise and mixed is preferable.
As the method of supplying acetone, a method of supplying it all at once or a method of supplying it in parts can be used, but since the reaction for producing bisphenol is an exothermic reaction, it is gradually dropped and supplied (divided). (Supply) method is preferred.

[Preparation method of monoalkyl sulfate]
Examples of the method for preparing monoalkyl sulfate used in the present invention include a method obtained by mixing sulfuric acid with an aliphatic alcohol described later and a method obtained by mixing sulfuric acid with a monoalkyl metal sulfate such as sodium sulfate monoalkyl. ..
In the present invention, the monoalkyl sulfate mixed with orthocresol and acetone is used.
Even if the pre-prepared product is mixed with orthocresol and acetone in the reactor, monoalkyl sulfate is produced by adding sulfuric acid and fatty alcohol into the reactor, and this is mixed with orthocresol and acetone. May be good.

Further, in the present invention, the mixing of monoalkyl sulfate means that the produced monoalkyl sulfate and other components are mixed by mixing sulfuric acid, an aliphatic alcohol and other components in any of the reaction steps. include.
Since heat is generated when the aliphatic alcohol and sulfuric acid are mixed, the mixing is preferably equal to or lower than the boiling point of the aliphatic alcohol.

[Fatty alcohol]
Examples of the fatty alcohol used in the present invention include methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, t-butanol, n-pentanol, i-pentanol and n-hexanol. , N-Heptanol, n
Examples thereof include alkyl alcohols having 1 to 12 carbon atoms such as octanol, n-nonanol, n-decanol, n-undecanol, n-dodecanol, ethylene glycol, diethylene glycol, and triethylene glycol. The aliphatic alcohol is
As the number of carbon atoms increases, lipophilicity increases, it becomes difficult to mix with sulfuric acid, and it tends to be difficult 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 fatty alcohol to sulfuric acid is low, the amount of monoalkyl sulfate generated is small and reaction time is required, and when the concentration is high, the concentration of fatty alcohol is low. Therefore, the molar ratio of fatty alcohol to sulfuric acid is high. , Preferably 0.00001 or more,
It is more preferably 0.0001 or more, still more preferably 0.0005 or more, preferably 50 or less, more preferably 30 or less, still more preferably 10 or less.

In the present invention, a method is preferable in which the aliphatic alcohol is previously supplied to the reactor together with the orthocresol, and then acetone is added dropwise and mixed.
In the present invention, the aliphatic alcohol may be mixed with acetone in advance and then supplied to the reactor together.

[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, acetone may be abundant in mesityl oxide (dimerization product) or the like, which may promote dehydration dimerization of fatty alcohols and oxidatively decompose thiols. In addition, if the concentration of sulfuric acid used is low, the reaction time will be long, and 2,2-bis (4) will be efficient.
-Hydroxy-3-methylphenyl) There is a risk that it will be difficult to produce propane.
Therefore, the concentration of sulfuric acid used is preferably 50% by weight or more, more preferably 60% by weight or more. In addition, the sulfuric acid concentration is high (that is, the concentration of water in the sulfuric acid is low), and
When the amount of the solvent (details will be described later) to be mixed with acetone is small with respect to the amount of water contained in the sulfuric acid, the amount of acetone is increased to mesityl oxide (dimerization product) or the like, and the fatty alcohol is dehydrated. The concentration of sulfuric acid used is preferably 95% by weight or less, more preferably 90% by weight or less, because there is a risk of promoting dimerization and oxidatively decomposing 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 the solvent (details will be described later) to be premixed with acetone is large with respect to the amount of water contained in the sulfuric acid. The concentration of sulfuric acid used is preferable because acetone can suppress the increase in the amount of mesityl oxide (dimerization product), the dehydration dimerization of aliphatic alcohols, and the oxidative decomposition of thiol. Is 90% by weight or more, more preferably 95% by weight or more.

In the present invention, the concentration of sulfuric acid at the time of charging is the concentration of sulfuric acid at the time of supplying to the reactor. The solvent is a solvent that is mixed with acetone (details will be described later).
As described above, in the present invention, the mixing of monoalkyl sulfate means that the produced monoalkyl sulfate and other components are mixed by mixing sulfuric acid, fatty alcohol and other components in any of the reaction steps. In this case, the molar ratio of sulfuric acid to acetone is such that sulfuric acid is diluted with water produced as a by-product during the condensation reaction and takes a reaction time when it is small, and when it is large, acetone is mesityl oxide (dimerization product). ) Etc. From these facts, the molar ratio of sulfuric acid to acetone is preferably 0.01 or more, more preferably 0.0.
5 or more, more preferably 0.1 or more, and 10 or less, more preferably 8
Below, it is more preferably 5 or less.
In the present invention, a method is preferable in which the sulfuric acid is supplied in advance to the reactor together with the aliphatic alcohol and the orthocresol, and then acetone is added dropwise and mixed.

[Thiol]
In the present invention, it is preferable to have a thiol present in the reaction system. Examples of thiols 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, butyl mercaptan, and pentyl mercaptan. Alkyl mercaptans such as hexyl mercaptan, heptyl mercaptan, octyl mercaptan, nonyl mercaptan, decyl mercaptan, undecyl, and dodecyl mercaptan.

In the present invention, when the molar ratio of the thiol to acetone is low, the effect of improving selectivity tends to be inferior, and when it is high, the thiol is mixed with 2,2-bis (4-hydroxy-3-methylphenyl) propane. There is fear, and there is concern that the quality will deteriorate as a result. From these facts, the molar ratio of the thiol to acetone is preferably 0.001 or more, more preferably 0.005 or more, still more preferably 0.01 or more, preferably 1 or less, and more preferably 0.5. Below, it is more preferably 0.1 or less.

In the present invention, the thiol can be previously supplied to the reactor together with sulfuric acid, fatty alcohol and orthocresol, and then acetone can be added dropwise and mixed. Also, sulfuric acid,
A method is possible in which the thiol is premixed with acetone in a reactor containing an aliphatic alcohol and orthocresol, and then added dropwise. In the method of supplying the thiol together with sulfuric acid, aliphatic alcohol and orthocresol in advance to the reactor, the thiol tends to be oxidatively decomposed by sulfuric acid. It is preferable to mix with an alkyl, and specifically, a method in which the thiol is mixed with acetone in advance and then added dropwise to a reactor containing sulfuric acid, an aliphatic alcohol and orthocresol is preferable.

[solvent]
In the present invention, it is necessary to premix acetone with a solvent and then supply it to a reactor to mix it with orthocresol. According to the present invention, by mixing acetone with a solvent in advance and then mixing it with orthocresol, the yield of the desired bisphenol is improved. Acetone and solvent may be mixed in advance by mixing all the amounts of each of them to be used, or by mixing some of them in advance, but the whole amount may be mixed in advance from the viewpoint of not complicating the process and the yield. It is preferable to do so.

In the present invention, aromatic hydrocarbons can usually be used as the solvent used for premixing with acetone. Further, the solvent used for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane can be recovered and purified by distillation or the like and reused. Examples of the aromatic hydrocarbon used include benzene, toluene, xylene, ethylbenzene, diethylbenzene, isopropylbenzene, and mesitylene. When the solvent is reused, a solvent having a low boiling point is preferable.

The solvent will be supplied and present in the reaction system that produces bisphenol. If the amount of solvent used in the reaction to produce bisphenol is too small for the amount of sulfuric acid used to prepare monoalkyl sulfate, the produced bisphenol will decompose and the amount of bisphenol obtained will decrease. There is. On the other hand, if it is too much for the amount of sulfuric acid,
The condensation reaction rate with ketones or aldehydes and aromatic alcohols may decrease, and it may take time to produce bisphenol. Therefore, the amount of the solvent used is preferably 0.05 times or more, more preferably 0.1 times or more, preferably 10 times or less, and more preferably 5 times or less with respect to the amount of sulfuric acid. In particular, when using high-concentration sulfuric acid, the amount of sulfuric acid should be increased.
1 times or more is preferable, 2 times or more is more preferable, 10 times or less is preferable, and 5 times or less is more preferable.

As described above, in the present invention, acetone is premixed with a solvent and then supplied to a reactor to be mixed with orthocresol. However, after premixing orthocresol and monoalkyl sulfate, this is a mixture of acetone and a solvent. It is preferable to mix with and to suppress the condensation reaction of mesityl oxide and the like. Specifically, for example, a method in which a solvent is previously mixed with a mixture of acetone and thiol in a reactor containing sulfuric acid, an aliphatic alcohol and orthocresol and then dropped and mixed, sulfuric acid, an aliphatic alcohol and orthocresol. It is possible to mix thiol in a reactor containing alcohol, and then add a mixture of solvent and acetone to the reactor and mix them. If the solvent is pre-supplied to the reactor with sulfuric acid, fatty alcohols and orthocresol
Since the hydrophobicity of the solution in the reactor increases and the reaction time of 2,2-bis (4-hydroxy-3-methylphenyl) propane becomes longer, acetone is premixed with the solvent and then mixed with orthocresol. However, a method of premixing the solvent with a mixture of acetone and thiol in a reactor containing sulfuric acid, an aliphatic alcohol and orthocresol and then dropping the solvent is particularly preferable.

[2,2-bis (4-hydroxy-3-methylphenyl) propane production reaction]
The 2,2-bis (4-hydroxy-3-methylphenyl) propane production reaction of the present invention is
Using monoalkyl sulfate as a catalyst, orthocresol and acetone can be condensed to produce 2,2-bis (4-hydroxy-3-methylphenyl) propane. Therefore, the production method of the present invention comprises the step of mixing orthocresol, acetone, and monoalkyl sulfate in a reactor to produce 2,2-bis (4-hydroxy-3-methylphenyl) propane. The reaction to produce 2,2-bis (4-hydroxy-3-methylphenyl) propane by mixing and condensing orthocresol and acetone is an exothermic reaction, so when acetone is dropped and supplied to the reactor, the reactor The temperature rises. Therefore, when acetone is added dropwise to mix orthocresol, the reactor is cooled. When the reaction temperature of this condensation reaction is high, the amount of acetone tends to increase and the selectivity of 2,2-bis (4-hydroxy-3-methylphenyl) propane tends to decrease. Further, at low temperatures, a mixture of orthocresol, sulfuric acid and an aliphatic alcohol in the reactor may coagulate. from these things,
The temperature at which the mixture of acetone and the solvent is mixed with monoalkyl sulfate and orthocresol in the reactor is preferably 0 ° C. or higher, more preferably 10 ° C. or higher, still more preferably 25 ° C. or higher, and 60 ° C. or lower. , More preferably 70 ° C. or lower, still more preferably 40 ° C. or lower.

In the present invention, monoalkyl sulfate can be used as a catalyst, and acetone can be added dropwise and mixed with orthocresol, and then mixed to complete (ripen) the reaction. When the aging temperature is high, 2,2-bis (4-hydroxy-3-methylphenyl) propane may be decomposed by an acid, and when the aging temperature is low, aging may take time. From these facts, the aging temperature after the above-mentioned formation reaction is preferably 20 ° C. or higher, more preferably 25 ° C. or higher, still more preferably 30 ° C. or higher, 80 ° C. or lower, more preferably 75 ° C. or lower, still more preferably. It is 70 ° C. or lower.

In the present invention, the condensation reaction usually requires acetone dropping time and aging time (the total of acetone dropping time and aging time is taken as the reaction time). If the reaction time is long, there is a concern that the produced 2,2-bis (4-hydroxy-3-methylphenyl) propane may be decomposed by an acid, so that the reaction time is preferably within 30 hours, more preferably within 25 hours. , More preferably within 20 hours. The condensation reaction can be stopped by adding water equal to or more than the amount of sulfuric acid used to reduce the sulfuric acid concentration.

[Purification method]
The 2,2-bis (4-hydroxy-3) obtained by the production reaction in the present invention.
-Methylphenyl) Propane can be purified 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 by distillation is distilled off before crystallization and then crystallization is performed.

[Use of 2,2-bis (4-hydroxy-3-methylphenyl) propane]
The 2,2-bis (4-hydroxy-3-methylphenyl) propane of the present invention is a polyether used in various applications such as optical materials, recording materials, insulating materials, transparent materials, electronic materials, adhesive materials, and heat-resistant materials. Various thermoplastic resins such as resins, polyester resins, polyarylate resins, polycarbonate resins, polyurethane resins, acrylic resins, and various thermosetting resins such as epoxy resins, unsaturated polyester resins, phenol resins, polybenzoxazine resins, and cyanate resins. It can be used as a constituent component such as, a curing agent, an additive, or a precursor thereof. 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 2,2-bis (4-hydroxy-3-methylphenyl) propane produced in the present invention, is the 2,2-bis (4-hydroxy-3) produced by the above-mentioned method. -Methylphenyl) Propane and a carbonic acid diester such as diphenyl carbonate can be produced by transesterifying 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 2,2-bis (4-hydroxy-3-methylphenyl) propane 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 2,2-bis (4-hydroxy-3-methylphenyl) propane. The amount of diphenyl carbonate used for the 2,2-bis (4-hydroxy-3-methylphenyl) propanol is often large in that the produced polycarbonate resin has few terminal hydroxyl groups and is excellent in thermal stability of the polymer. It is preferable, and it is preferable that the transesterification reaction rate is high and the amount is small in that it is easy to produce a polycarbonate resin having a desired molecular weight. Specifically, for example, with respect to 1 mol of 2,2-bis (4-hydroxy-3-methylphenyl) propane, usually 1.001 mol or more, preferably 1.002 mol or more, usually 1.3 mol or less. ,
It is preferable to use 1.2 mol or less.

As a raw material supply method, the 2,2-bis (4-hydroxy-3-methylphenyl) propane and diphenyl carbonate can be supplied in solid form, but one or both of them are melted and supplied in a liquid state. Is preferable.
A catalyst is usually used in the transesterification reaction of diphenyl carbonate with 2,2-bis (4-hydroxy-3-methylphenyl) propane to produce a polycarbonate resin.
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 catalyst is usually 0.05 μmol or more, preferably 0.08 μmol or more, more preferably 0.10 μmol with respect to 1 mol of 2,2-bis (4-hydroxy-3-methylphenyl) propane or diphenyl carbonate. Above, on the other hand, usually 100 μmol or less, preferably 5
It is used in the range of 0 μmol or less, more preferably 20 μmol or less.
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 to produce a polymer.

[Polycarbonate resin]
As described above, the 2,2-bis (4-hydroxy-3-methylphenyl) propane obtained by the production method of the present invention has a very high purity and is less colored, so that it can be obtained by the production method of the present invention. High-purity polycarbonate resin can be obtained by polycondensing 2,2-bis (4-hydroxy-3-methylphenyl) propane and diphenyl carbonate in the presence of an ester exchange 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, mesityl oxide, acetone, methanol, dodecanethiol,
Toluene, sulfuric acid, hydrochloric acid, acetonitrile, acetic acid, ammonium acetate, sodium hydroxide,
Sodium bicarbonate, 3-mercaptopropionic acid, cesium carbonate, and 2,2-bis (
For 4-hydroxy-3-methylphenyl) propane, a special grade reagent manufactured by Wako Pure Chemical Industries, Ltd. was used.
As diphenyl carbonate, a product manufactured by Mitsubishi Chemical Corporation was used.

[analysis]
The composition analysis of the bisphenol C production reaction solution 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 reaction yield (mol%) of bisphenol C based on acetone is 2,2-bis (4-) contained in the reaction solution from the peak detected by high performance liquid chromatography at a wavelength of 280 nm.
The concentration of hydroxy-3-methylphenyl) propane was calculated, and the molar amount of the 2,2-bis (4-hydroxy-3-methylphenyl) propane contained in the bisphenol C production reaction solution was calculated from the concentration. , The molar amount of the 2,2-bis (4-hydroxy-3-methylphenyl) propane ÷ the molar amount of the raw material acetone × 100%.

The amount of mesityl oxide produced in the bisphenol C production reaction solution is the area of mesityl oxide detected by high performance liquid chromatography at a wavelength of 210 nm ÷ wavelength 210 nm.
It was calculated by the area of 2,2-bis (4-hydroxy-3-methylphenyl) propane detected by 100 (area%).
The analysis of dodecyl mercaptan and dodecyl disulfide in the bisphenol C production reaction solution was performed by gas chromatography under the following procedure and conditions. The device used was "GC-17A" manufactured by Shimadzu Corporation. The column is "DB-1" manufactured by Agilent Technologies.
(Inner diameter 0.53 mm, column length 30 m, film thickness 1 μm) was used. The carrier gas was helium, the flow rate was 5.58 cm / min ³ , and the linear velocity was 47.4 cm / sec. The inlet temperature was 250 ° C. and the detector temperature was 280 ° C. The temperature rise pattern of the column was analyzed by first holding at 150 ° C. for 5 minutes, then raising the temperature to 295 ° C. at 13 ° C. per minute, and holding at 295 ° C. for 15 minutes.

For the residual amount of dodecyl mercaptan in the bisphenol C production reaction solution, the weight of dodecyl mercaptan contained in the reaction solution was calculated from the analytical value of dodecyl mercaptan obtained by gas chromatography, and the weight of the dodecyl mercaptan ÷ the raw material dodecyl mercaptan. It was calculated by multiplying the weight of 100 by 100%.

(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, 3.3 g (0.10 mol) of methanol and 128 g (1.18 mol) of orthocresol under a nitrogen atmosphere. After the addition, 67 g of 85 wt% sulfuric acid was slowly supplied. Further, 5.5 g of dodecyl mercaptan was supplied to the separable flask.
34 g (0.58 mol) of acetone and 147 g of toluene were supplied to the dropping funnel and mixed to obtain a mixed solution of acetone and toluene. The mixture was slowly added dropwise to the separable flask over 30 minutes. This reaction solution was reacted at 40 ° C. for 2 hours. After the reaction is over
100 g of toluene and 100 g of dechlorinated water were 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, dechlorinated water was added to the obtained organic phase and the mixture was stirred for 10 minutes. After stirring, the mixture was allowed to stand and the aqueous phase was extracted. When a part of the obtained organic phase was taken out and the amount of bisphenol C produced by high performance liquid chromatography was confirmed, the reaction yield based on acetone was 71 mol%. The amount of mesityl oxide, which is a dimer of acetone, in the bisphenol C production reaction solution was 0.05 area% with respect to the area of bisphenol C.

Comparative Example 1
In a full jacket type 1 liter separable flask equipped with a thermometer, a stirrer and a 500 ml dropping funnel, 3.3 g (0.10 mol) of methanol, 128 g (1.18 mol) of orthocresol, under a nitrogen atmosphere. And after adding 147 g of toluene, 67 g of 85% by weight sulfuric acid was slowly supplied. Further, 5.5 g of dodecyl mercaptan was supplied to the separable flask. Acetone 34 g (0.58 mol) was supplied to the dropping funnel to supply the dropping funnel.
It was slowly dropped into a separable flask over 30 minutes and supplied. This reaction solution was used for 2 hours, 4
The reaction was carried out at 0 ° C. After completion of the reaction, the treatment was carried out in the same manner as in Example 1. When a part of the obtained organic phase was taken out and evaluated, the reaction yield was 41 mol%. The amount of mesityl oxide, which is a dimer of seton, was 0.21 area% with respect to the area of bisphenol C.

Comparative Example 2
With reference to the method described in Example 1 of JP-A-2014-40376, 2,2-bis (
4-Hydroxy-3-methylphenyl) Propane was synthesized. In a 500 mL three-necked flask equipped with a Dimroth condenser and a thermometer, 45 g (0.42 mol) of orthocresol,
18 g (0.31 mol) of acetone, 6 g of toluene and 2 g of 3-mercaptopropionic acid were added and stirred. The three-necked flask was immersed in a water bath at 25 ° C., and 35 wt% hydrochloric acid 47 was placed therein.
g was slowly added and stirred. After raising the temperature of the water bath to 30 ° C., 10 g of 98 wt% sulfuric acid
Was dropped over 1 hour and supplied to the three-necked flask. As a result, one hour after the start of the reaction,
The reaction solution solidified and could not be stirred and mixed. This state was maintained at 25 ° C. for 6.5 hours. Using the obtained reaction solution, it was washed with warm water according to the method described in Example 1 of JP-A-2014-40376. When a part of the obtained organic phase was taken out and the amount of 2,2-bis (4-hydroxy-3-methylphenyl) propane produced by high performance liquid chromatography was confirmed, the reaction yield based on acetone was 52 mol. %Met. The amount of mesityl oxide produced, which is a dimer of acetone, in the bisphenol C production reaction solution was 1.70 area% with respect to the area of bisphenol C.

From the above results, in the known method, a large amount of mesityl oxide, which is a dimerized product of acetone, is produced, and the selectivity of 2,2-bis (4-hydroxy-3-methylphenyl) propane is lowered, and the selectivity of 2,2-bis (4-hydroxy-3-methylphenyl) propane is lowered. It was found that there was a problem that the reaction solution solidified, resulting in poor mixing, and further reaction time was required.
For Example 1, Comparative Example 1 and Comparative Example 2, the place of supply of toluene, the properties of the reaction solution, the amount of mesityloxide produced in the bisphenol C production reaction solution, and the reaction yield of bisphenol C are summarized in Table 1. As a result, by supplying toluene together with acetone, it is possible to reduce the hydrophobicity of the reactor, efficiently condense acetone and orthocresol, and suppress the formation of mesityl oxide, and the reaction yield of bisphenol C can be suppressed. It turns out that the rate can be significantly improved.

Example 2
After putting 5 g (0.16 mol) of methanol and 191 g (1.77 mol) of orthocresol in a separable flask under a nitrogen atmosphere, 100 g of 80% by weight sulfuric acid was slowly supplied, and the dropping funnel was charged. 50 g (0.86 mol) of acetone, 221 g of toluene
, 7.5 g of dodecyl mercaptan was supplied and mixed, and the same treatment as in Example 1 was performed except that a mixed solution was obtained. When a part of the obtained organic phase was taken out and the amount of bisphenol C produced by high performance liquid chromatography was confirmed, the reaction yield based on acetone was 85 mol%, and the mesityl oxide in the bisphenol C production reaction solution was found. The amount of bisphenol C was 0.02 area% with respect to bisphenol C. The residual amount of dodecyl mercaptan in the bisphenol C production reaction solution was confirmed by gas chromatography and found to be 44%.

Example 3
In Example 1, 5 g (0.16 mol) of methanol and 191 g of orthocresol.
(1.77 mol), 100 g of 80% by weight sulfuric acid, 7.5 g of dodecyl mercaptan, 50 g (0.86 mol) of acetone, and 221 g of toluene were treated in the same manner as in Example 1. When a part of the obtained organic phase was taken out and the amount of bisphenol C produced by high performance liquid chromatography was confirmed, the reaction yield based on acetone was 40 mol%.
The amount of mesityl oxide was 0.19 area% with respect to the area of bisphenol C. Moreover, when the residual amount of dodecyl mercaptan was confirmed by gas chromatography, it was 4%.

For Examples 2 and 3, the residual amount of dodecyl mercaptan, the amount of mesityl oxide, and the amount of bisphenol C in the bisphenol C production reaction solution are summarized in Table 2. As a result, it was found that by premixing dodecyl mercaptan and toluene with acetone and then reacting, the decomposition of dodecyl mercaptan can be suppressed, the production of mesityl oxide can be suppressed, and the reaction yield of bisphenol C can be significantly improved. rice field.

Example 4
Full jacket 1.5 with thermometer, stirrer and 100 ml dropping funnel
Refrigerant at 0 ° C. was flowed through the jacket of a liter separable flask. There, under a nitrogen atmosphere, 274 g of toluene, 14 g of methanol, and 230.4 g of orthocresol (2.
13 mol) was added and the internal temperature was cooled to 5 ° C. Then, 90 g of 98 wt% sulfuric acid was added.
To the dropping funnel, 16.5 g of toluene, 5.4 g of dodecanethiol, and 61. of acetone.
2 g (1.06 mol) of the mixture was added. When the internal temperature of the separable flask reached 5 ° C., the mixture was slowly added dropwise over 1 hour. After the dropping, the mixture was stirred at 10 ° C. for 1 hour, then further heated to 45 ° C. and stirred at 45 ° C. for 1 hour. To the obtained reaction solution, 231 g of a 28 wt% sodium hydroxide aqueous solution was added. While raising the temperature to 80 ° C., 28% by weight sodium hydroxide aqueous solution was added so that the pH was between 5-8. After the internal temperature reached 80 ° C., the aqueous phase was withdrawn and washed with saturated aqueous sodium hydrogen carbonate and washed with water. When a part of the obtained organic phase was taken out and the amount of bisphenol C produced by high performance liquid chromatography was confirmed, the reaction yield based on acetone was 78 mol%.

Example 5
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 8.2.

Claims (9)

A method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane from orthocresol and acetone.
It comprises a production step of mixing the orthocresol, the acetone, and monoalkyl sulfate in a reactor to produce 2,2-bis (4-hydroxy-3-methylphenyl) propane.
Acetone used in the production step is 2,2-bis (4-hydroxy-3-methylphenyl) propane, which is previously mixed with a solvent and then supplied to the reactor and mixed with the orthocresol. Manufacturing method.


The 2,2-bis (4-hydroxy-3-methyl) according to claim 1, wherein the orthocresol and the monoalkyl sulfate are mixed in advance and then mixed with the mixture of acetone and a solvent. Phenyl) Propane production method. 2.2 according to claim 2, wherein the temperature at which the mixture of acetone and the solvent is mixed with the mixture of monoalkyl sulfate and orthocresol in the reactor is 0 ° C. or higher and 60 ° C. or lower. -A method for producing bis (4-hydroxy-3-methylphenyl) propane. The method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane according to any one of claims 1 to 3, wherein the solvent is an aromatic hydrocarbon. The 2,2-bis (4-hydroxy-3-methylphenyl) according to claim 1 to 4, wherein the monoalkyl sulfate comprises a step of producing from sulfuric acid and an aliphatic alcohol.
Propane manufacturing method. The production of 2,2-bis (4-hydroxy-3-methylphenyl) propane according to claim 5, wherein the molar ratio of the fatty alcohol to sulfuric acid is 0.0001 or more and 10 or less. Method. 2. According to any one of claims 1 to 6, wherein the step of producing 2,2-bis (4-hydroxy-3-methylphenyl) propane is carried out in the presence of thiol. A method for producing 2-bis (4-hydroxy-3-methylphenyl) propane. The method for producing 2,2-bis (4-hydroxy-3-methylphenyl) propane according to claim 7, wherein the thiol and the acetone are mixed and then mixed with the monoalkyl sulfate. .. It is characterized in that 2,2-bis (4-hydroxy-3-methylphenyl) propane is produced by the production method according to any one of claims 1 to 8, and a polycarbonate resin is produced using the propane. Method for manufacturing polycarbonate resin.