JP2003261670A - Production method of aromatic polycarbonate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To produce an aromatic polycarbonate having excellent color tone and high transparency, without using dichloromethane which is difficult to use due to environmental issues. <P>SOLUTION: In the method for producing an aromatic polycarbonate, a halogenated carbonyl compound is reacted with an aromatic dihydroxy compound containing 2,2-bis-(4-hydroxyphenyl)propane and 1,1'-bis-(4-hydroxyphenyl)- m-diisopropyl benzene, and an alkali metal or alkaline earth metal base, wherein into a two-phase mixed solution comprising (1) an aqueous phase containing the aromatic dihydroxy compound and the alkali metal or alkaline earth metal base and (2) an organic phase containing a halogenated benzene, the halogenated carbonyl compound, a molecular weight modifier and a polymerization catalyst are supplied to perform a polymerization reaction. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an aromatic polycarbonate. More specifically, it relates to a method for producing an aromatic polycarbonate with little coloring by an interfacial polymerization method.

[0002]

2. Description of the Related Art Polycarbonates obtained by conventional manufacturing methods have a poor hue, particularly a heat-resistant hue, and have problems, for example, in optical material applications. When the production is carried out by the solution polymerization method, a large amount of base (for example, pyridine) is required, and the residual nitrogen content that affects the color tone is reduced, so that the removal of pyridine requires a great deal of labor and cost. Although dichloromethane is preferably used as a solvent in the interfacial polymerization method, it is difficult to use it industrially due to recent environmental problems and emission regulations.
Under such circumstances, there has been a demand for improvement in the polymerization method of aromatic polycarbonate used for optical materials.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to produce an aromatic polycarbonate having a good color tone and excellent transparency without using dichloromethane which is difficult to use due to environmental problems and the like.

[0004]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that an aqueous solution containing a mixture of two or more kinds of aromatic dihydroxy compounds and an alkali metal base contains chlorobenzene and the like. By preparing a two-phase liquid mixture with halogenated benzene and reacting with a carbonyl halide compound, it is possible to produce an aromatic polycarbonate with good color tone and excellent transparency without using dichloromethane. Heading, completed the present invention.

That is, the present invention provides (1) a method for producing an aromatic polycarbonate by reacting an aromatic dihydroxy compound with an alkali metal or alkaline earth metal base with a carbonyl halide compound to obtain an aromatic dihydroxy compound and an alkali. Polymerization reaction is performed by supplying a carbonyl halide compound, a molecular weight modifier and a polymerization catalyst to a two-phase mixture containing an aqueous phase containing a metal or alkaline earth metal base and an organic phase containing a halogenated benzene. (2) The aromatic dihydroxy compound is 2,2-bis-
(4-Hydroxyphenyl) propane and 1,1'-
A method for producing an aromatic polycarbonate in which bis- (4-hydroxyphenyl) -m-diisopropylbenzene is contained, wherein the halogenated benzene is chlorobenzene. (3) The mixture of the aromatic dihydroxy compound is 2,
2-bis- (4-hydroxyphenyl) propane 5-
Method for producing aromatic polycarbonate which is a mixture of 85 mol% and 1,1′-bis- (4-hydroxyphenyl) -m-diisopropylbenzene 95 to 15 mol% (4) The halogenated carbonyl compound is phosgene, and the molecular weight is A method for producing an aromatic polycarbonate in which the regulator is pt-butylphenol and the polymerization catalyst is triethylamine (5) A method for producing the above aromatic polycarbonate having a YI value of 3 or less. (6) A method for producing an aromatic polycarbonate, in which the aromatic polycarbonate solution after the polymerization reaction is added dropwise to acetone, and then water is added dropwise to obtain a granular material of the aromatic polycarbonate.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The method for producing an aromatic polycarbonate of the present invention will be described in detail below. Specific examples of the aromatic dihydroxy compound according to the present invention include hydroquinone, resorcin, bis (4-hydroxyphenyl) methane, 1,1-bis (4′-hydroxyphenyl) ethane, and 1,2-bis (4 ′). -Hydroxyphenyl) ethane, bis (4-hydroxyphenyl) phenylmethane, bis (4-hydroxyphenyl) diphenylmethane, bis (4-hydroxyphenyl) -1-naphthylmethane, 1,1-bis (4'-hydroxyphenyl) −
1-phenylethane, 2,2-bis- (4'-hydroxyphenyl) propane, 2- (4'-hydroxyphenyl) -2- (3'-hydroxyphenyl) propane,
2,2-bis- (4'-hydroxyphenyl) butane,
1,1, -bis (4'-hydroxyphenyl) isobutane, 2,2-bis- (4'-hydroxyphenyl) octane, 2,2-bis- (3'-methyl-4'-hydroxyphenyl) propane, 2,2-bis- (3'-ethyl-4'-hydroxyphenyl) propane, 2,2-
Bis- (3'-n-propyl-4'-hydroxyphenyl) propane, 2,2-bis- (3'-isopropyl-4'-hydroxyphenyl) propane, 2,2-bis- (3'-sec- Butyl-4'-hydroxyphenyl) propane, 2,2-bis- (3'-tert-butyl-4'-hydroxyphenyl) propane, 2,2
-Bis- (3'-cyclohexyl-4'-hydroxyphenyl) propane, 2,2-bis- (3'-allyl-
4'-hydroxyphenyl) propane, 2,2-bis- (3'-methoxy-4'-hydroxyphenyl) propane, 2,2-bis- (3 ', 5'-dimethyl-
4'-hydroxyphenyl) propane, 2,2-bis-
(2 ', 3', 5 ', 6'-Tetramethyl-4'-hydroxyphenyl) propane, 2,2-bis- (3'-
Chloro-4'-hydroxyphenyl) propane, 2,
2-bis- (3 ', 5'-dichloro-4'-hydroxyphenyl) propane, 2,2-bis- (3'-bromo-4'-hydroxyphenyl) propane, 2,2-bis- (3' , 5'-Dibromo-4'-hydroxyphenyl) propane, 2,2-bis- (2 ', 6'-dibromo-3', 5'-dimethyl-4'-hydroxyphenyl) propane, bis (4-hydroxy) Phenyl) cyanomethane, 1-cyano-3,3-bis (4'-hydroxyphenyl) butane, 2,2-bis (4'-hydroxyphenyl) hexafluoropropane, 1,1'-bis-
(4-Hydroxyphenyl) -m-diisopropylbenzene, 1,1′-bis- (4-hydroxyphenyl)-
Bis (hydroxyaryl) alkanes such as p-diisopropylbenzene, 1,1-bis (4′-hydroxyphenyl) cyclopentane, 1,1-bis (4′-hydroxyphenyl) cyclohexane, 1,1-bis (4 '-
Hydroxyphenyl) -3,3,5-trimethylcyclohexane, 1,1-bis (4'-hydroxyphenyl)
Cycloheptane, 2,2-bis (1,1-bis (4'-
Bis (hydroxyaryl) cycloalkanes such as hydroxyphenyl) adamantane, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,
Bis (hydroxyaryl) ethers such as 3′-dimethyldiphenyl ether and ethylene glycol bis (4-hydroxyphenyl) ether, 4,4′-dihydroxydiphenyl sulfide, 4,4′-dihydroxydi-3,3′-dimethyldiphenyl Bis (hydroxyaryl) sulfides such as sulfides, 4,4′-dihydroxydiphenyl sulfoxide, bis (hydroxyaryl) sulfoxides such as 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfoxide, 4,4 ′
-Bis (hydroxyaryl) sulfones such as dihydroxydiphenylsulfone and 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone, bis (4-hydroxyphenyl) ketone, bis (4-hydroxy-3-)
Bis (hydroxyaryl) ketones such as methylphenyl) ketone, and 6,6′-dihydroxy-3,
3,3 ′, 3′-tetramethylspiro (bis) indane, trans-2,3-bis (4′-hydroxyphenyl) -2-butene, 9,9-bis (4′-hydroxyphenyl) fluorene, 3 , 3-bis (4'-hydroxyphenyl) -2-butanone, 1,6-bis (4'-hydroxyphenyl) -1,6-hexanedione, 1,1-
Dichloro-2,2-bis (4'-hydroxyphenyl)
Ethylene, 1,1-dibromo-2,2-bis (4′-hydroxyphenyl) ethylene, 1,1-dichloro-2,
2-bis (5′-phenoxy-4′-hydroxyphenyl) ethylene, α, α, α ′, α′-tetramethyl-
α, α'-bis (4-hydroxyphenyl) -p-xylene, α, α, α ', α'-tetramethyl-α, α'-
Bis (4-hydroxyphenyl) -m-xylene, 4,
4'-dihydroxydiphenyl etc. are mentioned. These may be used alone or in combination of two or more.

In the production method of the present invention, 2,2-bis- (4'-hydroxyphenyl) propane (hereinafter referred to as bisphenol A) and 1,2 It is preferable to use 1'-bis- (4-hydroxyphenyl) -m-diisopropylbenzene (hereinafter referred to as bisphenol M) in combination.

The use ratio of bisphenol A and bisphenol M is 5 to 85 mol% of bisphenol A and 95 to 15 mol% of bisphenol M, preferably 50 to 75 mol% of bisphenol A and bisphenol M.
It is 50 to 25 mol%.

The alkali metal or alkaline earth metal base (hereinafter abbreviated as base) used in the present invention is, for example,
It is a hydroxide of an alkali metal or an alkaline earth metal such as sodium hydroxide, potassium hydroxide and calcium hydroxide, and sodium hydroxide and potassium hydroxide, which are easily available, are preferable, and sodium hydroxide is particularly preferable.

The amount of the base used is preferably about 1.0 to 2.0 times equivalents, more preferably 1.3 to 1.7 times equivalents, relative to bisphenol A and bisphenol M. 1.0 for bisphenol A and bisphenol M
If the amount is less than the double equivalent, halophenolation of bisphenol A and bisphenol M does not proceed well, and hydrolysis of the carbonyl halide compound occurs. If the amount of bisphenol A and bisphenol M is more than 2.0 times equivalent, due to the action of excess base,
It is not preferable because hydrolysis of the carbonyl halide compound and / or haloformate compound and cleavage of the carbonate bond of the formed aromatic polycarbonate may occur.

The base is usually used in the form of an aqueous solution, and bisphenol A and bisphenol M are preferably dissolved in the aqueous solution for use in the reaction, but there is no problem in the reaction even in a heterogeneous dissolved state. Since the basic aqueous solutions of bisphenol A and bisphenol M are generally easily colored, they may be prepared by adding a reducing agent such as sodium sulfite, hydrosulfite, or sodium borohydride as an antioxidant. As water for preparing the basic aqueous solution of bisphenol A and bisphenol M, distilled water, deionized water or the like may be used. The amount of water used for preparing the basic aqueous solution of bisphenol A and bisphenol M is bisphenol A and bisphenol under the condition that the base is 1.0 to 2.0 equivalents relative to bisphenol A and bisphenol M. It is preferred to use the amount required to completely dissolve M.

Examples of the organic solvent halogenated benzene relating to the production method of the present invention include monosubstituted benzenes such as fluorobenzene, chlorobenzene, bromobenzene and iodobenzene, difluorobenzene, dichlorobenzene,
Examples include disubstituted benzenes such as dibromobenzene and chlorobromobenzene, and polysubstituted benzenes such as trichlorobenzene and tetrachlorohebenzene, with chlorobenzene being particularly preferred.

The amount of halogenated benzene is usually preferably such that the concentration of the aromatic polycarbonate in the halogenated benzene solution at the end of the polymerization is 5 to 35% by weight, preferably 10 to 20% by weight. Amounts are particularly preferred.
When the concentration of the aromatic polycarbonate in the organic solvent solution is low, a large amount of halogenated benzene is required, and the productivity is deteriorated, which is not preferable. Further, when the concentration of the halogenated benzene solution of the aromatic polycarbonate is close to the saturated concentration, the viscosity of the halogenated benzene solution of the aromatic polycarbonate becomes very high, which lowers the efficiency of the interfacial polymerization reaction, It is not preferable because problems such as deterioration of handleability occur. Also, after reducing the amount of halogenated benzene at the start of the reaction, adding halogenated benzene at any time during the reaction, or further increasing the viscosity of the halogenated benzene solution of the aromatic polycarbonate as the molecular weight increases, It is also possible to add halogenated benzene to efficiently carry out the polymerization reaction.

The volume ratio of the organic phase to the water phase in the reaction is preferably 0.7 to 1.5: 1 as the volume ratio of the organic phase to the water phase when the amount of water used in the reaction is within the above range. And more preferably 0.8 to 1.2: 1.

Suitable polymerization catalysts for the production method of the present invention include tertiary amines, quaternary ammonium salts, tertiary phosphines, quaternary phosphonium salts, or nitrogen-containing heterocyclic compounds, salts thereof, imino ethers and salts thereof. Examples thereof include salts and compounds having an amide group. Preferably, it is a trialkylamine which is a tertiary amine, more preferably a trialkylamine having no branch on the carbon atoms at the 1-position and 2-position and an alkyl group having 1 to 4 carbon atoms, for example, , Triethylamine, tri-n-propylamine, diethyl-n-propylamine, and tri-n-butylamine, and triethylamine is particularly preferable in terms of easy availability and excellent catalytic effect. The amount of the polymerization catalyst is preferably 0.003 to 0.7 mol% based on the number of moles of the aromatic dihydroxy compound.
The amount is more preferably 0.009 to 0.6 mol% and more preferably 0.01 to 0.4 mol% with respect to the number of moles of the aromatic dihydroxy compound. 0.003
When the amount of the polymerization catalyst is less than mol%, the effect for forming the aromatic polycarbonate is not sufficiently expressed, a long reaction time is required, and the effect of suppressing the hydrolysis of the carbonyl halide compound and / or the haloformate compound is obtained. Is not admitted. The amount of the polymerization catalyst is 0.7 mol% based on the number of moles of the aromatic dihydroxy compound.
When the amount is larger, an aromatic polycarbonate having a large polydispersity index is often obtained, which is not so preferable from the viewpoint of physical properties.

The molecular weight regulator related to the production method of the present invention is for adjusting the molecular weight in the process of producing an aromatic polycarbonate, and generally, a monovalent hydroxyaromatic compound is used. Alkali metal or alkaline earth metal salt of monovalent hydroxyaromatic compound, chloroformate derivative of monovalent hydroxyaromatic compound, compound having monovalent carboxylic acid group, and compound having monovalent carboxylic acid group It may be an alkali metal or alkaline earth metal salt, an acid chloride derivative of a compound having a monovalent carboxylic acid group, or the like. Examples of the monovalent hydroxyaromatic compound include phenol, p-tert-butylphenol, o-cresol, m-cresol and p.
-Cresol, o-ethylphenol, p-ethylphenol, p-cumylphenol, p-phenylphenol, p-cyclohexylphenol, pn-octylphenol, p-isooctylphenol, p-nonylphenol, p-methoxyphenol, p -N-hexyloxyphenol, p-isopropenylphenol,
o-chlorophenol, m-chlorophenol, p-chlorophenol, o-bromophenol, m-bromophenol, p-bromophenol, pentabromophenol, pentachlorophenol, β-naphthol, α-
Naphthol, 2- (4'-methoxyphenyl) -2-
(4 ′ ′-hydroxyphenyl) propane and the like.
The alkali salt or alkaline earth metal salt of a monovalent hydroxyaromatic compound is an alkali metal or alkaline earth metal salt such as the sodium salt, potassium salt or calcium salt of the above-mentioned monovalent hydroxyaromatic compound. The chloroformate derivative of a monovalent hydroxyaromatic compound is the above-mentioned chloroformate derivative of a monovalent hydroxyaromatic compound. Examples of the compound having a monovalent carboxylic acid group include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, heptanoic acid, caprylic acid, 2,2-dipropionic acid, 3-methylbutyric acid, 3,3-dimethyl. Butyric acid, 4-methylvaleric acid, 3,3-dimethylvaleric acid, 4-methylcaproic acid, 2,4-dimethylvaleric acid, 3,5-dimethylcaproic acid, fatty acids such as phenoxyacetic acid, benzoic acid, p
-Propoxybenzoic acid, p-butoxybenzoic acid, p-pentyloxybenzoic acid, p-hexyloxybenzoic acid,
Benzoic acids such as p-octyloxybenzoic acid. 1
The alkali metal or alkaline earth metal salt of a compound having a divalent carboxylic acid group is an alkali metal or alkaline earth metal salt of the above-mentioned compound having a monovalent carboxylic acid group such as sodium salt, potassium salt or calcium salt. The acid chloride derivative of the compound having a monovalent carboxylic acid group is the acid chloride derivative of the compound having a monovalent carboxylic acid group described above. These may be used alone or in combination of two or more. Phenol, p-cumylphenol or p-tert-butylphenol is preferable from the viewpoint of easy availability.

The amount of the molecular weight modifier used is determined according to the average molecular weight of the target aromatic polycarbonate.
The aromatic polycarbonate produced by the production method of the present invention can be made to have an arbitrary average molecular weight by changing the amount of the molecular weight modifier used. However, molding processability, thermal decomposition resistance, impact resistance, etc. 1000 considering physical properties
A weight average molecular weight of 0 to 100,000 is preferable, and 200
A weight average molecular weight of 00-80,000 is particularly preferred. The amount of the molecular weight modifier necessary for producing the aromatic polycarbonate having the weight average molecular weight in the above range is 10 to 10 with respect to the number of moles of the aromatic dihydroxy compound used.
0.5 mol% is preferable, and 8.0-1.5 mol% is more preferable.

As the carbonyl halide compound relating to the present invention, carbonyl chloride called phosgene is usually used, but a carbonyl halide compound derived from a halogen other than chlorine, for example, carbonyl bromide, carbonyl iodide, fluorinated compound. Carbonyl may be used, and two or more of these halogenated carbonyl compounds may be used in combination. Further, it may be a compound having an ability to form a haloformate group, for example, trichloromethylchloroformate which is a dimer of phosgene or bis (trichloromethyl) carbonate which is a trimer of phosgene. Of these, it is preferable to use phosgene.

The amount of the carbonyl halide compound used in the present invention is preferably 1.0 to 1.3 times the molar amount of the aromatic dihydroxy compound. The use of a carbonyl halide compound in an amount less than 1.0 times the molar amount results in formation of unreacted aromatic dihydroxy compound and is a factor in producing a colored aromatic polycarbonate, and the hydroxy end groups remain excessively. Since the aromatic polycarbonate has a low end-capping rate, the molecular weight and the molecular weight distribution during molding become large. Further, when a carbonyl halide compound is used in an amount of more than 1.3 times, a large amount of oligomers whose terminals are terminated by haloformate groups are produced, and the ratio of haloformate terminals to hydroxy terminals of the oligomer in the reaction system is haloformate. Since the terminal groups become excessive, an aromatic polycarbonate having a small molecular weight, which is terminated by a haloformate terminal group, is produced at a normal polymerization time, which is not preferable.

In the method for producing an aromatic polycarbonate of the present invention, a carbonyl halide compound is supplied to a two-phase mixed solution comprising an aromatic dihydroxy compound, a water phase consisting of a base and water, and an organic phase containing halogenated benzene. A haloformate reaction is carried out, and then a polymerization catalyst is supplied to carry out the polymerization reaction to produce an aromatic polycarbonate.

The method for preparing a two-phase liquid mixture comprising an aqueous phase containing an aromatic dihydroxy compound, a base and water and an organic phase containing a halogenated benzene is a method for preparing an aromatic dihydroxy compound, a base, water, a halogenated benzene and a desired compound. By mixing the antioxidant with, by stirring to dissolve the aromatic dihydroxy compound may be prepared a two-phase mixture,
After preparing an aqueous solution containing an aromatic dihydroxy compound, a base and water in advance, halogenated benzene may be supplied to prepare a two-phase mixed solution. It is also possible to prepare a mixture of an aromatic dihydroxy compound, water and a halogenated benzene in a suspended state, and to dissolve the aromatic dihydroxy compound while supplying an aqueous solution of a base to the mixture. When supplying the carbonyl halide compound to the two-phase mixture, it is preferable to maintain stirring at least to an extent sufficient to prevent the separation of the aqueous phase and the organic phase of the two-phase mixture.

In the production method of the present invention, the supply rate of the carbonyl halide compound is 0.5 to 2.9 mol% per minute with respect to the aromatic dihydroxy compound, that is, the total carbonyl compound is 35 to 35%. It is preferable that the feeding rate is in the range of 260 minutes, and the feeding rate is 0.8 to 2.6 mol% per minute with respect to the aromatic dihydroxy compound, that is, the feeding rate is 40 to 160 minutes. Of 1.0 to 1.6 mol% per minute, that is, a rate of supplying the entire amount in 60 to 130 minutes is particularly preferable. When the carbonyl halide compound is supplied at a rate within the above range, no change is observed in various physical properties such as the terminal group sealing ratio, the molecular weight distribution, the transparency and the thermal decomposition resistance of the aromatic polycarbonate produced. , Good. The carbonyl halide compound may be supplied in any state of gas, liquid or solution.For example, when the carbonyl halide compound is phosgene, it is preferable to supply it in a gas state, but it is preferable to dissolve it in an organic solvent. It is also possible to supply it as an organic solvent solution. The carbonyl halide compound can be supplied continuously or intermittently. In the case of continuous supply, it is necessary to always supply at a constant rate from the beginning of the haloformate reaction to the end of the haloformate reaction. Preferably, even in the case of intermittent or multi-stage divided supply, it is preferable to evenly divide and supply. It is also possible to continuously supply the carbonyl halide compound, temporarily stop the supply, and then restart the supply.

The haloformate reaction in the present invention is a reaction of a hydroxy group of an aromatic dihydroxy compound with a carbonyl halide compound using a base as a dehydrochlorinating agent to give a haloformate derivative of an aromatic dihydroxy compound or an oligomer having a haloformate end group. It is a reaction to produce.

The polymerization reaction in the present invention is a reaction of an aromatic dihydroxy compound haloformate derivative or an oligomer having a haloformate end group produced by a haloformate reaction with an aromatic dihydroxy compound or an oligomer having a hydroxy end group to produce a desired compound. It is a reaction for producing a molecular weight aromatic polycarbonate.

In the method for producing an aromatic polycarbonate of the present invention, the molecular weight modifier is present during the haloformate reaction. It is not preferable to add the molecular weight modifier after the completion of the haloformate reaction because it becomes difficult to produce an aromatic polycarbonate having a high end-capping ratio. Regarding the method of adding the molecular weight modifier, the entire amount may be present in the initial stage of the reaction prior to the supply of the carbonyl halide compound, or may be supplied along with the supply of the polymerization catalyst or the carbonyl halide compound.

The polymerization catalyst can be supplied intermittently or continuously with the supply of the carbonyl halide compound. It is preferable to supply the same amount of time as the total amount of the carbonyl halide compound.

Under the interfacial reaction conditions for forming an aromatic polycarbonate, only a very small amount of the aromatic dihydroxy compound was dissolved in the organic phase at the initial stage of the reaction, but it was sequentially haloformated with the supply of the carbonyl halide compound. The aromatic dihydroxy compound dissolves and the amount of haloformate compound in the organic phase increases. With the increase of this haloformate compound, by supplying the polymerization catalyst into the system, the reaction of the haloformate compound is carried out efficiently, the end groups of the low molecular weight region of the aromatic polycarbonate are efficiently sealed, and the control of the molecular weight is accurate. Aromatic polycarbonates produced by

As a method of supplying the molecular weight modifier to the reaction system, it is possible to supply it in a solution state, a solid state, an organic solvent solution, an aqueous solution or the like, and the organic solvent solution or the aqueous solution state is supplied. Is preferred. It may be mixed with the polymerization catalyst and supplied intermittently or continuously in the form of an organic solvent solution or aqueous solution, or may be supplied separately from the polymerization catalyst in the form of an organic solvent solution or aqueous solution. When the molecular weight modifier is continuously supplied, the supply rate is preferably substantially the same as the above-mentioned supply rate of the polymerization catalyst. Further, the carbonyl halide compound is continuously supplied, the polymerization catalyst is continuously supplied with the supply of the carbonyl halide compound, and the molecular weight regulator is intermittently divided into multiple stages with the supply of the carbonyl halide compound. Carbonyl halide compound is continuously supplied, the polymerization catalyst is intermittently supplied with the supply of the carbonyl halide compound, and the molecular weight modifier is continuously supplied with the supply of the carbonyl halide compound. A method, a method in which a carbonyl halide compound is dividedly supplied in multiple stages, and a polymerization catalyst and a molecular weight modifier are continuously supplied may be used.

In the present invention, the polymerization catalyst is a liquid, a solid,
It is supplied in various states such as a gas state, an organic solvent solution or an aqueous solution, and it is preferably supplied in a liquid state, an organic solvent solution or an aqueous solution state. The concentration of the organic solvent solution or the aqueous solution of the polymerization catalyst may be any concentration, but is preferably 2 ppm to 80% by weight. When the polymerization catalyst is supplied as an organic solvent solution, the organic solvent solution of the polymerization catalyst is used by using an organic solvent in an amount of 40% by weight or less, more preferably 25% by weight or less based on the total amount of the organic solvent used in the polymerization reaction. Prepare. When the polymerization catalyst is supplied as an aqueous solution, it is preferably prepared using water in an amount of 25% by weight or less of the amount of water used for preparing the basic aqueous solution of the aromatic dihydroxy compound.

In the present invention, the first step for producing an aromatic polycarbonate is to dissolve an aromatic dihydroxy compound, a base, a halogenated benzene, a molecular weight modifier and an aromatic dihydroxy compound in the presence of a predetermined amount of a base. A mixture consisting of the required amount of water and optionally an antioxidant is prepared. At this time, the temperature at which the aromatic dihydroxy compound is dissolved is preferably 20 ° C. or lower from the viewpoint of preventing coloring during dissolution.

Next, a carbonyl halide compound is fed to the above mixture over a period of 35 to 260 minutes. At about the same time as the supply of the carbonyl halide compound, the polymerization catalyst is supplied to the above mixture intermittently or continuously in a liquid state, an organic solvent solution or an aqueous solution. The supply time of the polymerization catalyst is preferably approximately the same as the supply time of the carbonyl halide compound. Alternatively, the polymerization catalyst may be supplied after the supply of the carbonyl halide compound is completed.

The aromatic polycarbonate thus produced is in a state of an organic solvent solution, and is then neutralized with an acid and washed with water repeatedly until substantially no electrolyte is present. Thereafter, the halogenated benzene solution is added dropwise to acetone with sufficient stirring, and then water is added dropwise to precipitate the polycarbonate to form a powder. The stirring speed is 100 to 1000 rpm, preferably 250 to 750 rpm. At this time, the temperature is 15 to 5
It is 5 ° C, preferably 20-40 ° C. The amount of acetone used is 2 to 5 times, preferably 2.5 to 4 times the amount of the halogenated benzene solution, and the amount of water used is 0.5 to 2 times, preferably 0.7 to 1 times the amount of the halogenated benzene solution. .5 times.

The aromatic polycarbonate produced by the present invention is characterized by having a good color tone, and has a YI (yellowness index) value of 3 or less, preferably 2 or less.

[0034]

EXAMPLES The present invention will be described in detail below with reference to examples. However, the present invention is not limited thereby. Example 1 1l equipped with stirrer, gas inlet pipe, exhaust pipe and thermometer
Pure water 393.27 g was added to the flask, and 2,2-bis- (4-hydroxyphenyl) propane 30.30 g was added.
(133 mmol), 1,1'-bis- (4-hydroxyphenyl) -m-diisopropylbenzene 19.70
g (56.9 mmol), sodium hydrosulfite 0.10 g, pt-butylphenol 0.85 g
(5.7 mmol), 45% sodium hydroxide aqueous solution 5
5.78 g (628 mmol) was added and vigorously stirred. Chlorobenzene (494.35 g) was charged, and phosgene (28.10 g, 284 mmol) was added at 0.7 g / m 2.
It was blown in at a rate of in and vigorously stirred at 40 ° C. or lower for 1 h. Add 0.31g of triethylamine, 2h at 40 ℃
Polymerized. The reaction solution was filtered under reduced pressure, separated, and separated into an organic phase.
% Aqueous sodium hydroxide solution (500 g) was added for washing, filtration under reduced pressure, and liquid separation. 35% hydrochloric acid 6g, pure water 50 in the organic phase
0 g was added, and the mixture was neutralized and separated. The organic phase was washed 5 times with 500 g of pure water, filtered under reduced pressure, and the filtrate was added dropwise to 2400 ml of acetone at room temperature for 1 hour.
It was dripped at h to precipitate the powdery particles of polycarbonate.
After vacuum filtration, vacuum drying was carried out at 80 ° C. to obtain 46.9 g of polycarbonate powder or granules. The molecular weight was Mw 46000, nitrogen was 1 ppm or less by trace element analysis, and the yellowness index (YI) value was 2.0.

Comparative Example 1 50 equipped with a stirrer, a gas introduction pipe, an exhaust pipe and a thermometer
To a 0 ml flask, 186.2 g of dichloromethane was added, and 32.0 g of bisphenol A (140.2 mmo
l), bisphenol M 20.81 g (60.1 mm
ol), 0.602 g of pt-butylphenol (4.
0 mmol), 77.86 g of pyridine (984.3 mo)
1) was charged, stirred and cooled to 15 ° C. To this, 25.76 g (260.4 mmol) of phosgene was added at 0.7 / mi.
It was blown in at a rate of n and stirred at 20 to 25 ° C. for 3 hours. PT
0.301 g (2.0 mmol) of BP was charged and stirred for 1 h. In another flask, 58.88 g of 35% hydrochloric acid and water 1
After charging 16.47 g, the reaction solution was added dropwise thereto at 25 ° C. or lower, stirred for 1 h, and separated. The organic phase is methanol 30
0 g was added dropwise at 40 ° C. to precipitate polycarbonate.
The crude polycarbonate obtained was converted into dichloromethane 18
Dissolved in 0 g, hydrosulfite 1.04 g, 49
% Aqueous sodium hydroxide (2.09 g) dissolved in 400 g of water to wash the solution, and the layers were separated. The organic phase was repeatedly washed with water until the pH was 8 or less and the conductivity was 2 μS / cm. The organic phase was added dropwise to 300 g of methanol at 40 ° C. to precipitate a polycarbonate, and the obtained powder and granules were filtered and dried under reduced pressure to obtain 43.52 g of a polycarbonate. The molecular weight of the obtained polycarbonate is Mw 47,000, nitrogen is 50 ppm by trace element analysis, and the yellowness index (Y
I) The value was 4.2.

[0036]

According to the present invention, it is possible to produce an aromatic polycarbonate having a good color tone and excellent transparency.

Continued front page    (72) Inventor Takahisa Oguchi             30 Asamu-cho, Omuta City, Fukuoka Prefecture             In the company F term (reference) 4J029 AA10 AB04 AC02 AD10 BB13A                       BB16A HA01 HC01 JA091                       JA203 JA283 JB043 JB063                       JB192 JB193 JC031 JF031                       JF041 JF141 KA01 KB02                       KB03 KB04 KB05 KB12 KB13                       KB17 KB18 KE11 KF04

Claims (6)

[Claims] 1. A method for producing an aromatic polycarbonate by reacting an aromatic dihydroxy compound and an alkali metal or alkaline earth metal base with a carbonyl halide compound, wherein the aromatic dihydroxy compound and the alkali metal or alkaline earth metal are used. A process for producing an aromatic polycarbonate in which a carbonyl halide compound, a molecular weight modifier and a polymerization catalyst are supplied to a two-phase mixture containing an organic phase containing an aqueous phase halogenated benzene containing a base to carry out a polymerization reaction. 2. The aromatic dihydroxy compound is 2,2-bis- (4-hydroxyphenyl) propane and 1,2.
The method for producing an aromatic polycarbonate according to claim 1, which is a mixture containing 1'-bis- (4-hydroxyphenyl) -m-diisopropylbenzene, and the halogenated benzene is chlorobenzene. 3. The aromatic dihydroxy compound is 2,2-
Bis- (4-hydroxyphenyl) propane 5-85
Mol% and 1,1'-bis- (4-hydroxyphenyl)
The method for producing an aromatic polycarbonate according to claim 2, which is a mixture of 95 to 15 mol% of -m-diisopropylbenzene. 4. The process for producing an aromatic polycarbonate according to claim 2, wherein the carbonyl halide compound is phosgene, the molecular weight regulator is pt-butylphenol, and the polymerization catalyst is triethylamine. 5. The method for producing an aromatic polycarbonate according to claim 2, which has a YI value of 3 or less. 6. The method for producing an aromatic polycarbonate according to claim 2, wherein the aromatic polycarbonate solution after the polymerization reaction is added dropwise to acetone, and then water is added dropwise to obtain a granular product of the aromatic polycarbonate.