JPH07165899A - Production of aromatic polycarbonate - Google Patents

Abstract

PURPOSE:To provide an arom. polycarbonate having a low low-molecular oligomer content and a narrow mol. wt. distribution. CONSTITUTION:An arom. polycarbonate is produced by conducting the interfacial polymn. of the reaction system contg. at least one arom. dihydroxy compd., a carbonate precursor, an alkali or alkaline earth metal base, water, and an org. solvent in the absence of a terminal blocking agent and a polycarbonate- forming catalyst to give an oligomer, continuing the interfacial polymn. of the oligomer in emulsion until the wt. average mol.wt. of the resulting prepolymer reaches 20-99% of that of the objective aromatic polycarbonate, adding a terminal blocking agent to the system, and further continuing the interfacial polymn. of the prepolymer.

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 having a low content of low molecular weight oligomers, a narrow molecular weight distribution, and excellent heat resistance.

[0002]

2. Description of the Related Art Conventionally, aromatic dihydroxy compounds,
Carbonate precursor, alkali metal or alkaline earth metal base, water, organic solvent, polycarbonate generation catalyst (also called polymerization catalyst, polycondensation catalyst, etc.) and end capping agent (molecular weight regulator, polymerization terminator, chain) A method for producing an aromatic polycarbonate using a terminating agent) is also known. US Patent No. 3275
No. 601, bisphenol A as an aromatic dihydroxy compound, phosgene as a carbonate precursor, sodium hydroxide as an alkali metal base, dichloromethane as an organic solvent, triethylamine as a polycarbonate production catalyst, and p-tert-butylphenol as an end capping agent. A method for producing the aromatic polycarbonate used is described. In this method, an end-capping agent is present in the reaction system before adding phosgene, and an aromatic polycarbonate is produced under ordinary stirring conditions.

JP-B-37-2198 discloses that a low molecular weight oligomer is formed by reacting an aromatic dihydroxy compound with a carbonate precursor in a two-phase medium of an organic solvent and an aqueous base solution, and then a high molecular weight polycarbonate. A method of making a polycarbonate comprising forming a. This method is a method of producing a high molecular weight polycarbonate in a reaction medium maintained in an emulsified state. In this method, an aromatic polycarbonate is produced without using an end-capping agent. JP 62-8
In 9723, an aqueous base solution of an aromatic dihydroxy compound and phosgene are reacted in the presence of an organic solvent,
A method for producing a polycarbonate by forming a low molecular weight polycarbonate and then forming a high molecular weight polycarbonate in a reaction medium maintained in an emulsified state is described. In this method, the terminal blocking agent is added before or immediately after the introduction of phosgene, and the obtained low molecular weight polycarbonate is in an emulsified state, and then,
A method for producing a polycarbonate, which comprises forming a high-molecular-weight polycarbonate by carrying out a polymerization reaction again by adding an end-capping agent when the concentration of the aromatic dihydroxy compound remaining in the aqueous phase shows a minimum value. is there. In this method, an end-capping agent is added before or immediately after the introduction of phosgene to produce an aromatic polycarbonate.

In JP-A-2-133425, a base aqueous solution of an aromatic dihydroxy compound is reacted with phosgene in the presence of an organic solvent to form a low molecular weight polycarbonate oligomer, and then the oligomer is emulsified. A method for producing a high-molecular-weight aromatic polycarbonate by maintaining the state and polymerizing is described. This method is characterized in that a tertiary amine is added at the time when the molecular weight of the polycarbonate in the emulsified state reaches 70% or more of the target molecular weight to form a high molecular weight aromatic polycarbonate. Is a manufacturing method. In this method, an end-capping agent is added to a low-molecular-weight polycarbonate oligomer and then emulsified to produce an aromatic polycarbonate.

JP-A-3-199231 discloses that a basic aqueous solution of an aromatic dihydroxy compound is reacted with phosgene in the presence of an organic solvent to form a low molecular weight polycarbonate oligomer containing a chloroformate group. Then, a method for producing an aromatic polycarbonate by polymerizing the oligomer in a water-in-oil type emulsion state in the presence of a base is described. In this method, the droplet diameter of the dispersed aqueous phase in the water-in-oil type emulsified state is 10 μm on average.
The method for producing an aromatic polycarbonate is characterized in that a tertiary amine is added after the following. In this method, an end-capping agent is added to a low-molecular-weight polycarbonate oligomer and then emulsified to produce an aromatic polycarbonate.

JP-A-4-277521 discloses a method for producing a polycarbonate resin in which OH / CO calculated from the absorbance ratio of OH and CO at the terminal measured by an infrared spectrophotometer is 0.25 or less. Is listed. In this method, a reaction mixture containing an oligomer obtained by the reaction of an aqueous base solution of an aromatic dihydroxy compound with phosgene in the presence of an organic solvent is emulsified by adding an endcapping agent and then emulsifying the reaction mixture. The method is characterized in that it is left standing and polymerized. In this method, an end-capping agent is added to a low-molecular weight oligomer (oligomer), which is then emulsified to produce an aromatic polycarbonate. However, using any of the above methods, the resulting aromatic polycarbonate has a large content of low molecular weight oligomers and a wide molecular weight distribution. At present, there is a demand for a method for producing an aromatic polycarbonate having a low content of low molecular weight oligomer and a narrow molecular weight distribution.

[0007]

An object of the present invention is to provide a method for producing an aromatic polycarbonate having a low content of low molecular weight oligomer and a narrow molecular weight distribution.

[0008]

Means for Solving the Problems The present inventors have completed the present invention as a result of extensive studies on a method for producing an aromatic polycarbonate in order to meet the above-mentioned demand. That is, the present invention provides a reaction system containing at least one aromatic dihydroxy compound, a carbonate precursor, an alkali metal or alkaline earth metal base, water and an organic solvent, and (A) the end capping agent and the polycarbonate generation catalyst. An interfacial polymerization reaction is carried out in the presence to form an oligomer, and (B) the oligomer is emulsified until the weight average molecular weight of the prepolymer becomes 20 to 99% of the weight average molecular weight of the obtained aromatic polycarbonate. The present invention relates to a method for producing an aromatic polycarbonate, which comprises the steps of continuing an interfacial polymerization reaction to form a prepolymer, (C) then adding a terminal blocking agent, and further performing an interfacial polymerization reaction.

In the production method of the present invention, an aromatic dihydroxy compound, a carbonate precursor, an alkali metal or alkaline earth metal base, water, an organic solvent and an end capping agent are used. In the production method of the present invention, the aromatic dihydroxy compound used is preferably a compound represented by the formula (1) or the formula (2). HO-Ar ¹ -Y-Ar ² -OH (1) HO-Ar ³ -OH (2) (In the formula, Ar ¹ , Ar ² and Ar ³ are each a divalent aromatic group, and Y is Ar ¹ Represents a linking group that connects Ar ² )

In formula (1) or formula (2), Ar ¹ ,
Ar ² and Ar ³ are each a divalent aromatic group, preferably a substituted or unsubstituted phenylene group. The substituent of the substituted phenylene group is a halogen atom, a nitro group, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group, an alkoxy group or the like. Ar ¹ and Ar
² is preferably both p-phenylene group, m-phenylene group or o-phenylene group, or one is p-
A phenylene group, one of which is an m-phenylene group or an o-phenylene group. Ar ¹ and Ar ² are particularly preferably both p-phenylene groups. Ar ³ is a p-phenylene group, m-phenylene group or o-phenylene group, and preferably a p-phenylene group or m-phenylene group. Y is a linking group that connects Ar ¹ and Ar ² , and is a single bond or a divalent hydrocarbon group, or —O—,
-S -, - SO -, - SO 2 -, - a group containing atoms other than carbon and hydrogen CO- like. Examples of the divalent hydrocarbon group include an alkylidene group such as a methylene group, an ethylene group, a 2,2-propylidene group and a cyclohexylidene group, an alkylidene group substituted with an aryl group, an aromatic group and other unsaturated groups. It is a hydrocarbon group containing a hydrocarbon group of.

Specific examples of the aromatic dihydroxy compound include bis (4-hydroxyphenyl) methane, bis (2-methyl-4-hydroxyphenyl) methane, bis (3-methyl-4-hydroxyphenyl) methane, 1,1. -Bis (4'-hydroxyphenyl) ethane, 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, 1,3
-Bis (4'-hydroxyphenyl) -1,1-dimethylpropane, 2,2-bis (4'-hydroxyphenyl) propane ["bisphenol A"], 2- (4'-
Hydroxyphenyl) -2- (3 "-hydroxyphenyl) propane, 1,1-bis (4'-hydroxyphenyl) -2-methylpropane, 2,2-bis (4'-hydroxyphenyl) butane, 1,1 -Bis (4'-hydroxyphenyl) -3-methylbutane, 2,2-bis (4'-hydroxyphenyl) pentane, 2,2-bis (4'-hydroxyphenyl) -4-methylpentane,
2,2-bis (4'-hydroxyphenyl) hexane,
4,4-bis (4'-hydroxyphenyl) heptane,
2,2-bis (4'-hydroxyphenyl) octane,
2,2-bis (4'-hydroxyphenyl) nonane, bis (3,5-dimethyl-4-hydroxyphenyl) methane,

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-hydroxyphenyl) cyanomethane, 3,3-
Bis (hydroxyaryl) alkanes such as bis (4′-hydroxyphenyl) -1-cyanobutane and 2,2-bis (4′-hydroxyphenyl) hexafluoropropane,

1,1-bis (4'-hydroxyphenyl) cyclopentane, 1,1-bis (4'-hydroxyphenyl) cyclohexane, 1,1-bis (3'-methyl-4'-hydroxyphenyl) cyclohexane , 1,1
-Bis (3 ', 5'-dimethyl-4'-hydroxyphenyl) cyclohexane, 1,1-bis (3', 5'-dichloro-4'-hydroxyphenyl) cyclohexane,
1,1-bis (4′-hydroxyphenyl) -4-methylcyclohexane, 1,1-bis (4′-hydroxyphenyl) -3,3,5-trimethylcyclohexane,
1,1-bis (4′-hydroxyphenyl) cycloheptane, 1,1-bis (4′-hydroxyphenyl) cyclooctane, 1,1-bis (4′-hydroxyphenyl) cyclononane, 1,1-bis ( 4'-hydroxyphenyl) cyclododecane, 2,2-bis (4'-hydroxyphenyl) norbornane, 8,8-bis (4'-hydroxyphenyl) tricyclo [5,2,1,0 ^2,6 ]
Bis (hydroxyaryl) cycloalkanes such as decane and 2,2-bis (4′-hydroxyphenyl) adamantane,

Bis (hydroxyaryl) such as 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether and ethylene glycol bis (4-hydroxyphenyl) ether.
Ethers, 4,4'-dihydroxydiphenyl sulfide, 3,3'-dimethyl-4,4'-dihydroxydiphenyl sulfide, 3,3'-dicyclohexyl-
4,4'-dihydroxydiphenyl sulfide, 3,
3'-diphenyl-4,4'-dihydroxydiphenyl sulfide, 3,3 ', 5,5'-tetramethyl-4,
Bis (hydroxyaryl) sulfides such as 4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfoxide, 3,3'-dimethyl-
Bis (hydroxyaryl) sulfoxides such as 4,4′-dihydroxydiphenyl sulfoxide, 4,4′-dihydroxydiphenyl sulfone, 3,3′-dimethyl-
4,4'-dihydroxydiphenyl sulfone, 3,3 '
-Bis (hydroxyaryl) sulfones such as diphenyl-4,4'-dihydroxydiphenylsulfone and 3,3'-dichloro-4,4'-dihydroxydiphenylsulfone, bis (4-hydroxyphenyl) ketone, bis (3- Bis (hydroxyaryl) ketones such as methyl-4-hydroxyphenyl) ketone,

Further, 3,3,3 ', 3'-tetramethyl-6,6'-dihydroxyspiro (bis) indane ["spirobiindane bisphenol"], 3,
3 ', 4,4'-tetrahydro-4,4,4', 4'-
Tetramethyl-2,2'-spirobi (2H-1-benzopyran) -7,7'-diol ["spirobichroman"], 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 (3′-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,
3,3-bis (4'-hydroxyphenyl) phthalide,
2,6-dihydroxydibenzo-p-dioxin, 2,
6-dihydroxythianthrene, 2,7-dihydroxyphenoxathiin, 9,10-dimethyl-2,7-dihydroxyphenazine, 3,6-dihydroxydibenzofuran, 3,6-dihydroxydibenzothiophene, 4,
4'-dihydroxybiphenyl, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 2,6
-Dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,7-dihydroxypyrene, hydroquinone, resorcin and the like. An aromatic dihydroxy compound containing an ester bond, which is produced by a reaction of 2 mol of bisphenol A and 1 mol of isophthaloyl chloride or terephthaloyl chloride is also useful. These may be used alone or in combination. The aromatic dihydroxy compound preferably used in the production method of the present invention is bisphenol A.

The carbonate precursor used in the production method of the present invention is preferably a carbonyl halide compound or a haloformate compound. As the carbonyl halide compound, carbonyl chloride called phosgene is usually used. Also useful are carbonyl halide compounds derived from halogens other than chlorine, such as carbonyl bromide, carbonyl iodide and carbonyl fluoride. Further, compounds having an ability to form a haloformate group, for example, trichloromethylchloroformate which is a dimer of phosgene and bis (trichloromethyl) carbonate which is a trimer of phosgene are also useful. These may be used alone or in combination.
Usually, the preferred carbonyl halide compound used is phosgene.

The haloformate compound is a mono- or bis-haloformate compound or an oligomeric haloformate compound, and is typically a compound represented by the formula (3). X- (O-R-O-C (= O)) _n- O-R-O-X (3) (In the formula, X represents a hydrogen atom or a halocarbonyl group,
At least one X is a halocarbonyl group and R is 2
Represents a valent aliphatic group or aromatic group, and n represents 0 or a positive integer) The compound represented by the formula (3) is a mono- or bishaloformate compound derived from an aliphatic dihydroxy compound, or It is an oligomeric haloformate compound, a mono- or bishaloformate compound derived from an aromatic dihydroxy compound, or an oligomeric haloformate compound. The oligomeric haloformate compounds may have R groups having different structures in the same molecule. These haloformate compounds may be used alone or as a mixture, and may be used in combination with a carbonyl halide compound.

In the formula (3), the divalent aliphatic group R is
An alkylene group having 2 to 20 carbon atoms, a cycloalkylene group having 4 to 12 carbon atoms, or a group represented by the formula (4). —R′—Ar ⁴ —R′— (4) (In the formula, the R ′ group represents an alkylene group having 1 to 6 carbon atoms,
The Ar ⁴ group represents a divalent aromatic group having 6 to 12 carbon atoms)

In the formula (3), specific examples of the aliphatic dihydroxy compound in which the R group is an aliphatic group include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5
-Pentanediol, 1,6-hexanediol, 1,
5-hexanediol, 1,7-heptanediol,
1,8-octanediol, 1,9-nonanediol,
1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, neopentyl glycol, 2-ethyl-1,6-hexanediol, 2-
Methyl-1,3-propanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol,
2,2-bis (4'-hydroxycyclohexyl) propane, xylylenediol, 1,4-bis (2'-hydroxyethyl) benzene, 1,4-bis (3'-hydroxypropyl) benzene, 1,4- Examples thereof include bis (4′-hydroxybutyl) benzene, 1,4-bis (5′-hydroxypentyl) benzene and 1,4-bis (6′-hydroxyhexyl) benzene. In formula (3), R
The aromatic dihydroxy compound whose group is an aromatic group is an aromatic dihydroxy compound represented by formula (1) or formula (2), and examples thereof include bisphenol A and hydroquinone.

In the production method of the present invention, the carbonate precursor particularly preferably used is phosgene, bisphenol A bischloroformate or bisphenol A oligomeric chloroformate compound. When a carbonyl halide compound is used, the amount of the carbonate precursor used is preferably about 0.9 to about 2.0 times the molar amount of the aromatic dihydroxy compound, and about 1.0 to
More preferably, about 1.5 times the molar amount. When a haloformate compound is used, the number of haloformate groups contained in the haloformate compound is relative to the number of hydroxy groups contained in the haloformate compound and the aromatic dihydroxy compound,
About 0.9 to about 1.5 times equivalent is preferable, and about 1.0 to about 1.3 times equivalent is more preferable. The carbonate precursor is
It can be used in any state of gas, liquid and solid. When the carbonyl halide compound is used, it is preferably used in a gaseous state or as an organic solvent solution dissolved in an organic solvent. When a haloformate compound is used, it is preferably used in a liquid state, a solid state or as an organic solvent solution dissolved in an organic solvent.

The alkali metal or alkaline earth metal base (hereinafter abbreviated as a base) used in the production method of the present invention is usually an alkali metal or alkaline earth such as sodium hydroxide, potassium hydroxide or calcium hydroxide. It is a metal hydroxide. These may be used alone or in combination. The preferred base is sodium hydroxide or potassium hydroxide. The amount of the base used is preferably about 1.0 to about the aromatic dihydroxy compound.
It is about 1.6 times equivalent. The base is usually used as an aqueous solution. Further, the aromatic dihydroxy compound may be dissolved in this aqueous solution before use. In this case, sodium sulfite, sodium hydrosulfite, sodium borohydride or the like may be added as an antioxidant. The whole amount of the base may be used in step (A), or a part of the amount may be used in step (A) and the remaining amount may be used in step (B) and / or step (C). You may. In addition, it is not necessary to use the entire amount of the base at once in each of the step (A), the step (B), and the step (C), and the base may be intermittently or continuously added to the reaction system. You may add to a reaction system, controlling pH to a fixed value or a fixed range.

The water used in the production method of the present invention is distilled water, ion-exchanged water, recovered water produced in producing an aromatic polycarbonate, or the like, and may be a mixture thereof. The water is preferably
Aqueous base solution, aqueous base solution of aromatic dihydroxy compound,
And / or used as an aqueous base solution of the end capping agent. The amount of water used is usually the aromatic dihydroxy compound 1
It is about 0.5 to about 5 liters per mole. When an aqueous base solution of an aromatic dihydroxy compound is prepared, the amount of water used may be at least the amount required to dissolve the aromatic dihydroxy compound and the base. For example, when the aromatic dihydroxy compound is bisphenol A, the amount thereof is about 0.8 to about 2.2 liters per 1 mol of bisphenol A.

The organic solvent used in the production method of the present invention is substantially inert to the reaction, substantially insoluble in water, and soluble in the aromatic polycarbonate. Good. The organic solvent is, for example,
With an aliphatic chlorinated hydrocarbon such as dichloromethane, chloroform, 1,2-dichloroethane, 1,2-dichloroethylene, trichloroethane, tetrachloroethane, dichloropropane, an aromatic chlorinated hydrocarbon such as chlorobenzene, dichlorobenzene, or a mixture thereof. is there. Also, for those chlorinated hydrocarbons or mixtures thereof,
An organic solvent in which an aromatic hydrocarbon such as toluene, xylene or ethylbenzene, an aliphatic hydrocarbon such as hexane, heptane or cyclohexane is mixed may be used. A particularly preferred organic solvent is dichloromethane. Further, the organic solvent used in the production method of the present invention may be a recovered organic solvent produced when producing the aromatic polycarbonate. Further, an organic solvent obtained by mixing the recovered organic solvent and a new organic solvent may be used. The amount of the organic solvent used is usually such that the concentration of the aromatic polycarbonate in the organic solvent solution containing the aromatic polycarbonate at the end of the polymerization is about 5 to about 35% by weight.
It is preferable to use it in an amount of about 10 to about 2
It is more preferable to use it so as to be 0% by weight.

The terminal blocking agent used in the production method of the present invention is for reacting with the terminal groups of the prepolymer formed in the step (B) to block the terminals. The end groups of the prepolymer are haloformate groups or hydroxy groups. The terminal blocking agent is a monovalent aromatic hydroxy compound, a monovalent aromatic hydroxy compound haloformate derivative, a monovalent carboxylic acid, or a monovalent carboxylic acid halide derivative. The monovalent aromatic hydroxy compound is, for example, phenol, p-cresol, o-ethylphenol, p-ethylphenol, p-isopropylphenol, p-tert-butylphenol, p-cumylphenol, p-cyclohexylphenol, p. -Octylphenol, p-nonylphenol, 2,4-xylenol, p-methoxyphenol, p-hexyloxyphenol, p-decyloxyphenol, o-chlorophenol, m-chlorophenol, p-chlorophenol, p-bromophenol, Pentabromophenol, pentachlorophenol, p-phenylphenol, p-isopropenylphenol, 2,4-di (1 '
-Methyl-1'-phenylethyl) phenol, β-naphthol, α-naphthol, p- (2 ', 4', 4'-
Trimethylchromanyl) phenol, phenol such as 2- (4′-methoxyphenyl) -2- (4 ″ -hydroxyphenyl) propane, or their alkali metal salts and alkaline earth metal salts. The haloformate derivative of a hydroxy compound is the haloformate derivative of the above monovalent aromatic hydroxy compound.

The monovalent carboxylic acid is, for example, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, heptanoic acid, caprylic acid, 2,2-dimethylpropionic acid, 3-methylbutyric acid, 3,3-dimethylbutyric acid. , 4-methylvaleric acid, 3,
3-dimethylvaleric acid, 4-methylcaproic acid, 2,4-
Dimethyl valeric acid, 3,5-dimethylcaproic acid, fatty acids such as phenoxyacetic acid or their alkali metal salts and alkaline earth metal salts, benzoic acid, p-methylbenzoic acid, p-tert-butylbenzoic acid, p- Benzoic acids such as propyloxybenzoic acid, p-butoxybenzoic acid, p-hexyloxybenzoic acid, p-octyloxybenzoic acid, p-phenylbenzoic acid, p-benzylbenzoic acid and p-chlorobenzoic acid, or alkalis thereof. Metal salts and alkaline earth metal salts. The monovalent carboxylic acid halide derivative is, for example, the above monovalent carboxylic acid halide derivative. These may be used alone or in combination. The endcapping agent preferably used is phenol, p-tert.
-Butylphenol or p-cumylphenol.

The amount of the end-capping agent used determines the weight average molecular weight of the obtained aromatic polycarbonate. The resulting aromatic polycarbonate has a weight average molecular weight of about 15,000 to about 150,000, preferably about 2
It is 0000 to about 100,000, more preferably about 25,000 to about 90,000, and particularly preferably about 30,000 to about 80,000. The amount of the end capping agent required for producing the aromatic polycarbonate having the weight average molecular weight in the above range is about 1.0 to about 10.0 mol% based on the number of moles of the aromatic dihydroxy compound. Is preferably about 1.5 to about 8.0 mol%, more preferably about 1.7 to about 7.0 mol%, and particularly preferably about 2.0 to about 6.0 mol%. It is 0 mol%. The end cap may be used in a solid state or a liquid state,
It may be used as an organic solvent solution, an aqueous solution or an aqueous base solution.

The production method of the present invention comprises: (A) a terminal capping agent and a polycarbonate in a reaction system containing at least one aromatic dihydroxy compound, a carbonate precursor, an alkali metal or alkaline earth metal base, water and an organic solvent. The interfacial polymerization reaction is performed in the absence of a production catalyst,
An oligomer is formed, and (B) the oligomer is subjected to an interfacial polymerization reaction in an emulsified state until the weight average molecular weight of the prepolymer becomes 20 to 99% of the weight average molecular weight of the obtained aromatic polycarbonate, thereby prepolymerizing the prepolymer. Formed,
(C) Next, a method for producing an aromatic polycarbonate comprising the steps of adding an end-capping agent and further performing an interfacial polymerization reaction.

In step (A), an interfacial polymerization reaction is carried out in the absence of the end capping agent and the polycarbonate-forming catalyst to form an oligomer. By oligomers herein is meant low molecular weight initial products. In this step, the interfacial polymerization reaction can be performed without stirring the reaction mixture, but it is preferable to stir the reaction mixture to perform the interfacial polymerization reaction from the viewpoint that the polymerization time can be shortened.
At that time, it is not necessary to continue stirring from the beginning to the end of the step (A), and if necessary, the stirring may be performed to such an extent that the separation of the organic phase and the aqueous phase is prevented. Usually, the stirring condition is preferably such that the organic phase and the aqueous phase are uniformly mixed. In some cases, the interfacial polymerization reaction of step (A) may be performed under vigorous stirring conditions. In addition, the interfacial polymerization reaction in the present specification includes all reactions that occur when an aromatic polycarbonate is produced by the method of the present invention, and those reactions are mainly the interface between an organic phase and an aqueous phase. Happens in.

Then, in step (B), the prepolymer is formed by interfacially polymerizing the oligomer obtained in step (A) in an emulsified state. The emulsified state in the present specification means, for example, a state in which the organic phase and the aqueous phase do not separate until the interfacial polymerization reaction is completed even if the emulsified state is allowed to stand without stirring or the like. As a method for obtaining the emulsified state, there are a method of stirring with a stirring device, a method of adding an alkaline aqueous solution, and the like. As the stirring device, a simple stirring device such as a paddle, a propeller, a turbine or a chi-type blade, a homogenizer, a mixer, a high-speed stirrer such as a homomixer, a static mixer, a colloid mill, an orifice mixer, a flow jet mixer, an ultrasonic emulsifying device. Etc. As a method for examining the emulsified state, for example, a laser diffraction particle size distribution measuring device (manufactured by Shimadzu Corporation,
SALD1100) and the like are available to measure the average droplet diameter of the dispersed phase. The average droplet diameter of the dispersed phase in the emulsified state measured by this method is, for example, about several tens of μm. Furthermore, the emulsified state is preferably a highly emulsified state in which the interfacial polymerization reaction is completed within a few hours, more preferably within a few hours. As a stirring device for obtaining such a highly emulsified state, a homogenizer, a mixer, a high-speed stirrer such as a homomixer,
There are agitation devices such as static mixers, colloid mills, orifice mixers, flow jet mixers and ultrasonic emulsifiers. The oligomer is brought into an emulsified state, preferably a highly emulsified state by the above method, and further an interfacial polymerization reaction is carried out to form a prepolymer. There are no particular restrictions on the stirring conditions after the emulsified state, and any of the stirring devices described above can be used. Further, after the emulsified state, it is also possible to carry out the interfacial polymerization reaction by allowing it to stand without stirring.

By the above operation, the weight average molecular weight of the prepolymer is 20 to 99%, preferably 35% to 95% of the weight average molecular weight of the obtained aromatic polycarbonate.
%, More preferably 40% to 90%, and particularly preferably 50% to 90%, the interfacial polymerization reaction is continued. By performing the interfacial polymerization reaction in the emulsified state, the polymerization rate becomes faster. Therefore, it is not necessary to use a polycarbonate-forming catalyst for the purpose of increasing the polymerization rate. The term “prepolymer” as used in the present specification means an aromatic polycarbonate having an unterminated end, which is obtained in the step (B). The weight average molecular weight of the prepolymer is about 3,000 to about 149000, preferably about 7,000 to about 95,000, more preferably about 10,000 to about 81,000, and particularly preferably about 15,000 to about 72,000. . As a method for investigating the weight average molecular weight of the prepolymer, a part of the reaction mixture obtained in the step (B) is taken out, and after static separation,
A method of analyzing the polymer component obtained by separating the organic phase, neutralizing with an acid, washing with water until the electrolyte is gone, and then distilling off the organic solvent by GPC (gel permeation chromatography) or the like. There is.

Next, in step (C), an end-capping agent is added to the prepolymer obtained in step (B) and an interfacial polymerization reaction is carried out to produce an aromatic polycarbonate. When the end-capping agent is added, for example, when the end-capping agent is added before the weight average molecular weight of the prepolymer reaches 20% of the weight-average molecular weight of the obtained aromatic polycarbonate, both ends are capped. The produced oligomer is produced in a large amount. Further, when the end-capping agent is added after the weight average molecular weight of the prepolymer reaches 99% of the weight average molecular weight of the obtained aromatic polycarbonate, it is difficult to control the weight average molecular weight. Therefore, the weight average molecular weight of the prepolymer is
The time when the above-mentioned weight average molecular weight is reached is preferable. There are no particular restrictions on the stirring conditions after the addition of the end-capping agent in step (C), and any stirring device described above can be used. The interfacial polymerization reaction is preferably performed in an emulsified state, and more preferably in a highly emulsified state. For example, while maintaining the emulsified state in step (B), a method of continuing stirring with an arbitrary stirring device, a stirring device for forming the emulsified state is used to re-form the emulsified state, and then the arbitrary stirring is performed. There is a method of performing an interfacial polymerization reaction by using a device or by leaving it stationary. In step (C), a polycarbonate-forming catalyst may be used, and in that case, the stirring conditions are not particularly limited. In addition, by adding the end-capping agent at the above time, the content of the low molecular weight oligomer having a molecular weight of 3000 or less is less than 3% by weight, preferably less than 2% by weight, more preferably 1% by weight.
% By weight and a weight average molecular weight of about 15,000 to about 150,000, preferably about 2,000 to about 1,000.
00, more preferably about 25000 to about 90,000,
Particularly preferably, aromatic polycarbonates of about 30,000 to about 80,000 can be produced.

The interfacial polymerization reaction in step (A) and step (B) of the production method of the present invention is carried out in the absence of a polycarbonate-forming catalyst. In the step (A) and / or the step (B), the presence of the polycarbonate-forming catalyst is not preferable because the aromatic polycarbonate obtained has a large nitrogen content. The interfacial polymerization reaction in the step (C) may be carried out in the absence of the polycarbonate-forming catalyst, or may be carried out in the presence of the polycarbonate-forming catalyst. When the interfacial polymerization reaction of the step (C) is carried out in the absence of a polycarbonate-forming catalyst, it is preferably carried out in an emulsified state. The polycarbonate generation catalyst suitable for the production method of the present invention is a tertiary amine, a quaternary ammonium salt,
Examples include tertiary phosphines, quaternary phosphonium salts, nitrogen-containing heterocyclic compounds and salts thereof, imino ethers and salts thereof, and compounds having an amide group.

Specific examples of the polycarbonate-forming catalyst include trimethylamine, triethylamine and tri-n-.
Propylamine, diethyl-n-propylamine, tri-n-butylamine, tri-n-hexylamine, N,
N-dimethylbenzylamine, N, N, N ', N'-tetramethyl-1,4-tetramethylenediamine, N,
N, N ', N'-tetra-n-butyl-1,6-hexamethylenediamine, N, N-dimethylcyclohexylamine, N, N-diethylcyclohexylamine, N, N
-Dimethylaniline, N, N-diethylaniline, 4-
Dimethylaminopyridine, 4-pyrrolidinopyridine,
N, N′-dimethylpiperazine, N-ethylpiperidine, N-methylmorpholine, 1,4-diazabicyclo [2,2,2] octane, benzyltrimethylammonium chloride, benzyltriethylammonium chloride, tetramethylammonium chloride, tetraethylammonium bromide , Methyltriethylammonium chloride, phenyltriethylammonium chloride, tetramethylammonium hydroxide,
Triethyl-n-octadecyl ammonium chloride, benzyl tri-n-butyl ammonium chloride, cyclohexyl trimethyl ammonium bromide, benzyl trimethyl ammonium fluoride, tetra-n-butyl ammonium fluoride, benzyl dimethyl phenyl ammonium chloride, tetra-n
-Heptyl ammonium iodide, m-trifluoromethylphenyl trimethyl ammonium bromide,
Triethylphosphine, triphenylphosphine, diphenylbutylphosphine, diphenyloctadecylphosphine, diphenylbenzylphosphine, tris (p-
Chlorophenyl) phosphine, phenylnaphthylbenzylphosphine, tetra (hydroxymethyl) phosphonium chloride, benzyltriethylphosphonium chloride, benzyltriphenylphosphonium chloride,
4-methylpyridine, 1-methylimidazole, 1,2
-Dimethylimidazole, 3-methylpyridazine, 4,
6-dimethylpyrimidine, 1-cyclohexyl-3,5
-Dimethylpyrazole, 2,3,5,6-tetramethylpyrazine and the like can be mentioned. These may be used alone or in combination. The polycarbonate generation catalyst is preferably a tertiary amine, more preferably having a total carbon number of 3 to
30 tertiary amines, particularly preferably triethylamine.

When the interfacial polymerization reaction of step (C) is carried out in the presence of a polycarbonate-forming catalyst, the amount used is about 0.00 with respect to the number of moles of the aromatic dihydroxy compound.
It may be 05 mol% or more. Even if the amount is excessively large, a remarkable effect cannot be expected. The amount of polycarbonate-forming catalyst is preferably about 0.0005 to about 5 mol% based on the number of moles of the aromatic dihydroxy compound. The polycarbonate production catalyst may be used in a liquid state or a solid state, and may be used as an organic solvent solution or an aqueous solution. When the interfacial polymerization reaction of step (C) is carried out in the presence of a polycarbonate-forming catalyst, step (C)
May be added to the reaction system at any time, and may be added to the reaction system intermittently or continuously.

The production method of the present invention can also produce a branched aromatic polycarbonate by using a branching agent. The branching agent suitable for the production method of the present invention has three or more reactive groups selected from an aromatic hydroxy group, a haloformate group, a carboxylic acid group, a carboxylic acid halide group, an active halogen atom and the like (the same or different). ) Has a compound. Specific examples of the branching agent include:
Phloroglucinol, 4,6-dimethyl-2,4,6-
Tris (4'-hydroxyphenyl) -2-heptene,
4,6-Dimethyl-2,4,6-tris (4'-hydroxyphenyl) heptane, 1,3,5-tris (4'-
Hydroxyphenyl) benzene, 1,1,1-tris (4′-hydroxyphenyl) ethane, 1,1,2-tris (4′-hydroxyphenyl) propane, α, α,
α'-Tris (4'-hydroxyphenyl) -1-ethyl-4-isopropylbenzene, 2,4-bis [α-methyl-α- (4'-hydroxyphenyl) ethyl] phenol, 2- (4'- Hydroxyphenyl) -2-
(2 ", 4" -dihydroxyphenyl) propane, tris (4-hydroxyphenyl) phosphine, 1,1,4
4-tetrakis (4′-hydroxyphenyl) cyclohexane, 2,2-bis [4 ′, 4′-bis (4 ″ -hydroxyphenyl) cyclohexyl] propane, α, α,
α ', α'-Tetrakis (4'-hydroxyphenyl)
-1,4-diethylbenzene, 2,2,5,5-tetrakis (4'-hydroxyphenyl) hexane, 1,1,
2,3-Tetrakis (4'-hydroxyphenyl) propane, 1,4-bis (4 ', 4 "-dihydroxytriphenylmethyl) benzene, 3,3', 5,5'-tetrahydroxydiphenyl ether, 3,5 -Dihydroxybenzoic acid, 3,5-bis (chlorocarbonyloxy) benzoic acid, 4-hydroxyisophthalic acid, 4-chlorocarbonyloxyisophthalic acid, 5-hydroxyphthalic acid,
5-chlorocarbonyloxyphthalic acid, trimesic acid trichloride, cyanuric acid chloride, 3,3-bis (4'-hydroxyphenyl) -2-oxo-2,3-
Examples include dihydroindole and 3,3-bis (4′-hydroxy-3′-methylphenyl) -2-oxo-2,3-dihydroindole.

The amount of the branching agent used is determined according to the degree of branching of the aromatic polycarbonate produced. Preferably, the amount of the aromatic dihydroxy compound is about 0.
05 to about 2.0 mol%. The branching agent may be used in a solid state or a liquid state, and may be used as an organic solvent solution, an aqueous solution or a basic aqueous solution. The timing of adding the branching agent is not particularly limited. The branching agent may be added in advance before the reaction, or may be added at any point in the reaction. These may be used alone or in combination. The production method of the present invention is generally carried out at about 10 ° C to the boiling temperature of the organic solvent used in the reaction. The manufacturing method of the present invention is
Usually carried out at atmospheric pressure, if desired, below atmospheric pressure,
Alternatively, it can be carried out under atmospheric pressure or higher.

The production method of the present invention may be carried out batchwise or continuously. The reactor used in the production method of the present invention is a known reactor such as a tank reactor, a tubular reactor or a packed tower, or a reactor in which those reactors are arbitrarily combined. These reactors can optionally be equipped with the agitator mentioned above. The production method of the present invention can be carried out batchwise by using a tank reactor. For example, a carbonate precursor or an organic solvent solution of a carbonate precursor is supplied to a reaction system containing an aromatic dihydroxy compound, a base, water and an organic solvent, and an interfacial polymerization reaction is carried out to form an oligomer. Be implemented. Then, an interfacial polymerization reaction is performed in an emulsified state to form a prepolymer, and step (B) is performed. Next, the terminal blocking agent is added, an interfacial polymerization reaction is further performed, and the step (C) is performed.

The production method of the present invention can be carried out in a semi-batch manner by using a tank reactor. For example,
An aqueous base solution of an aromatic dihydroxy compound, an organic solvent and a carbonate precursor, or a solution of a carbonate precursor in an organic solvent is continuously supplied to the reaction system to carry out an interfacial polymerization reaction to form an oligomer, and step (A) is performed. To be done. Subsequent operations are the same as in the batch type. Further, the production method of the present invention can be carried out in a continuous manner by using a tank-type continuous reaction device in which several tank-type reactors are connected in series. For example, an aqueous base solution containing an aromatic dihydroxy compound, a carbonate precursor and an organic solvent, or an organic solvent solution of a carbonate precursor is continuously supplied to the first tank. After a certain residence time in the first tank, the reaction mixture is continuously discharged into the second tank. And so on
After a certain residence time, the reaction mixture is continuously discharged into the next reaction vessel to produce an aromatic polycarbonate. At that time, any one or more reaction tanks are equipped with a stirring device for forming an emulsified state. The terminal blocking agent is continuously added to any reaction tank after the weight average molecular weight of the prepolymer becomes 20 to 99% of the weight average molecular weight of the obtained aromatic polycarbonate. In this case, one or more reaction tanks before the reaction tank, which are equipped with a stirring device for forming an emulsified state, are used in the step (A).
Corresponding to a reaction device for performing an interfacial polymerization reaction of, from a reaction tank equipped with a stirring device for forming an emulsified state,
One or a plurality of reaction tanks before the reaction tank to which the end-capping agent is added correspond to a reaction apparatus for performing the interfacial polymerization reaction in the step (B), and one or a plurality of reactions after the addition of the end-capping agent. The tank corresponds to the reaction device that performs the interfacial polymerization reaction in step (C). The method using the tank-type continuous reaction apparatus as described above,
An aromatic polycarbonate having a stable molecular weight and molecular weight distribution can be continuously produced.

Further, the production method of the present invention can be carried out continuously by using a tubular reactor. In this case, the production method of the present invention can be carried out by the same operation as in the case of using the tank type continuous reaction device. At that time, the terminal blocking agent has a weight average molecular weight of the prepolymer of 20 to 20% of the weight average molecular weight of the obtained aromatic polycarbonate.
It is continuously added from an arbitrary position in the middle of the tube after reaching 99%. The production method of the present invention can be carried out in a semi-batch type or a continuous type by using a continuous reaction device in which reaction devices such as a tank reactor, a tubular reactor or a packed tower are arbitrarily combined. For example, in the initial stage of the reaction, a tank reactor, a tubular reactor, a packed tower, and / or a device for making initial contact with the reaction solution are provided, and an interfacial polymerization reaction is carried out to continuously form an oligomer. (A) is implemented. Next, using a tank type reactor or a tubular reactor equipped with a stirring device for forming an emulsified state, an emulsified state is obtained, and a tank type reactor and / or a tubular type reactor is further used. An interfacial polymerization reaction is performed to form a prepolymer, and step (B) is performed. Next, an end capping agent is added to any subsequent reaction device, an interfacial polymerization reaction is further performed, and step (C) is performed. The manufacturing method of the present invention is carried out by the above operations.

The reaction mixture containing the aromatic polycarbonate produced by the process of the present invention is then treated in a continuous or batch operation to recover the aromatic polycarbonate. As the treatment of the reaction mixture, the organic phase containing the aromatic polycarbonate and the aqueous phase are separated, and the organic phase containing the aromatic polycarbonate is washed with water or a dilute aqueous alkaline solution, if necessary. Next, it is neutralized with a dilute aqueous acid solution. At that time, the acid used is hydrochloric acid,
Mineral acids such as sulfuric acid and phosphoric acid. Then, it is repeatedly washed with water until substantially no electrolyte is present. Then, the aromatic polycarbonate is recovered from the washed organic solvent solution of the aromatic polycarbonate by a known method. The method for recovering the aromatic polycarbonate is a method of removing the organic solvent by distillation or steam distillation, or an organic solvent (poor solvent) that does not dissolve the aromatic polycarbonate is added to the organic solvent solution of the aromatic polycarbonate to obtain the aromatic polycarbonate. In a solid state, and the organic solvent is separated from the obtained aromatic polycarbonate organic solvent slurry by a method such as filtration.

More specifically, the organic solvent is distilled off from the organic solvent solution of the aromatic polycarbonate and the organic solvent solution of the aromatic polycarbonate is saturated to crystallize the aromatic polycarbonate, which is then crushed. A method of removing the organic solvent contained by drying afterwards, a method of heating while removing the organic solvent from the organic solvent solution of the aromatic polycarbonate, a method of directly pelletizing the aromatic polycarbonate from a molten state, an organic solvent of the aromatic polycarbonate Method of supplying a solution into warm water and pulverizing a gel-like substance produced while removing an organic solvent, adding a poor solvent or a non-solvent to an organic solvent solution of an aromatic polycarbonate, and water, concentrating by heating, and solidifying. Of obtaining aromatic polycarbonate in the form of water as a water slurry, organic of aromatic polycarbonate A method of obtaining a solid-state aromatic polycarbonate as a water slurry by adding a solvent solution to warm water containing powder of aromatic polycarbonate and evaporating and distilling off an organic solvent, the organic solvent solution of the aromatic polycarbonate being an aromatic polycarbonate The organic solvent is evaporated and distilled off while supplying it to warm water containing the powder and the poor solvent to obtain a solid-state aromatic polycarbonate as a water slurry. Specific examples of the poor solvent or non-solvent, toluene, aromatic hydrocarbons such as xylene, pentane, hexane, octane, cyclohexane, aliphatic hydrocarbons such as methylcyclohexane, methanol, ethanol, propanol, butanol, pentanol, Alcohols such as hexanol, acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, ketones such as cyclohexanone, and esters such as ethyl acetate, butyl acetate and amyl acetate.

The aromatic polycarbonate produced by the method of the present invention can be used alone or in a mixture with another polymer as a molding material. Specific examples of other polymers include polyethylene, polypropylene, polystyrene, ABS resin, polymethylmethacrylate, polytrifluoroethylene, polytetrafluoroethylene, polyacetal, polyphenylene oxide, polybutylene terephthalate, polyethylene terephthalate, polyamide, polyimide, polyamideimide. , Polyetherimide, polysulfone, polyether sulfone, paraoxybenzoyl-based polyester, polyarylate, polysulfide and the like. The aromatic polycarbonate produced by the method of the present invention may be a pigment, a dye, a processing and heat stabilizer, an antioxidant, in a known method during or after the production of the aromatic polycarbonate, either alone or mixed with another polymer. , Hydrolysis stabilizers, impact stabilizers, ultraviolet absorbers, mold release agents, organic halogen compounds, alkali metal sulfonates, glass fibers, carbon fibers, glass beads, barium sulfate, TiO _{2 and} other known additives. You may add one or more types.

The aromatic polycarbonate produced by the method of the present invention is soluble in a specific organic solvent (for example, a halogenated hydrocarbon solvent such as dichloromethane), and is molded into a film from the organic solvent solution. It can be processed into a product. The aromatic polycarbonate produced by the method of the present invention is thermoplastic and can be easily molded from a melt by a known molding method such as injection molding, extrusion molding, blow molding, or lamination. Further, the aromatic polycarbonate produced by the method of the present invention, alone or in a state of being mixed with another polymer, optionally, by adding the above-mentioned additive, a chassis or housing material of electric equipment, electronic parts, It can be molded into automobile parts, building materials replacing glass, information recording medium bases such as data storage disks or audio compact disks, and optical materials such as lenses of cameras or spectacles.

[0044]

The present invention will be described in more detail by the following examples, but the present invention is not limited to the following examples. Example 1 A 10-liter baffled flask was equipped with a three-stage, six-blade stirrer and a reflux condenser. To this flask, 912 g (4.0 mol) of bisphenol A, 4 liters of dichloromethane and 4 liters of water were placed, and a nitrogen purge was performed to remove oxygen in the flask. Next, 1.5 liter of an aqueous solution of 1.8 g of sodium hydrosulfite and 442 g (11.04 mol) of sodium hydroxide was supplied to the above suspension, and bisphenol A was dissolved at 15 ° C. 471 g of phosgene in this mixture with stirring
(4.76 mol) was supplied for 30 minutes to obtain an oligomer solution. Next, the 3-stage, 6-blade stirrer was removed, and an SL-type homomixer [made by Tokushu Kika Kogyo Co., Ltd.] was attached instead, and the mixture was stirred at 5000 rpm for 3 minutes to obtain a highly emulsified state. Then, the SL homomixer was removed again, a three-stage six-blade stirrer was attached, and the mixture was further stirred for 7 minutes to obtain a prepolymer solution. After that, p-tert-
20.7 g of butylphenol (3.44 mol% based on bisphenol A) and 0.32 of triethylamine
50 ml of a dichloromethane solution of g (0.08 mol% with respect to bisphenol A) was added and stirred for 30 minutes to terminate the reaction. The weight average molecular weight of the prepolymer at the time of adding the terminal blocking agent is shown in Table 1 (Table 1). Then, the reaction mixture was allowed to stand, the organic phase was separated, neutralized with hydrochloric acid, and repeatedly washed with water until the electrolyte was exhausted. To the obtained solution of aromatic polycarbonate in dichloromethane, 2 liters of toluene and 5 liters of water were added and heated to 98 ° C. to distill off dichloromethane and toluene to obtain a powder of aromatic polycarbonate.

Example 2 A 10-liter baffled flask was equipped with a three-stage, six-blade stirrer and a reflux condenser. To this flask, 912 g (4.0 mol) of bisphenol A, 4 liters of dichloromethane and 4 liters of water were placed, and a nitrogen purge was performed to remove oxygen in the flask. Next, 1.5 liter of an aqueous solution of 1.8 g of sodium hydrosulfite and 442 g (11.04 mol) of sodium hydroxide was supplied to the above suspension, and bisphenol A was dissolved at 15 ° C. 471 g of phosgene in this mixture with stirring
(4.76 mol) was supplied for 30 minutes to obtain an oligomer solution. Next, the 3-stage, 6-blade stirrer was removed, an SL-type homomixer was attached instead, and the mixture was stirred at 7,000 rpm for 2 minutes to obtain a highly emulsified state. Then, without stirring as it is, the interfacial polymerization reaction is performed for 18 minutes while still standing,
A prepolymer solution was obtained. After that, the SL type homomixer was removed, a 3-stage six-blade stirrer was attached again, and 20.7 g of p-tert-butylphenol (3.44 mol% based on bisphenol A) and 0.32 g of triethylamine (based on bisphenol A) were added. 0.08
30% by adding 50 ml of a dichloromethane solution (mol%)
The reaction was terminated by stirring for a minute. Subsequent operations were performed in the same manner as in Example 1 to obtain an aromatic polycarbonate powder.

Example 3 A 10-liter baffled flask was equipped with a three-stage six-blade stirrer and a reflux condenser. To this flask, 912 g (4.0 mol) of bisphenol A, 4 liters of dichloromethane and 4 liters of water were placed, and a nitrogen purge was performed to remove oxygen in the flask. Next, 1.5 liter of an aqueous solution of 1.8 g of sodium hydrosulfite and 442 g (11.04 mol) of sodium hydroxide was supplied to the above suspension, and bisphenol A was dissolved at 15 ° C. 471 g of phosgene in this mixture with stirring
(4.76 mol) was supplied for 30 minutes to obtain an oligomer solution. Next, the 3-stage, 6-blade stirrer was removed, an SL-type homomixer was attached instead, and the mixture was stirred at 5000 rpm for 3 minutes to obtain a highly emulsified state. Then, the SL-type homomixer was again removed, a three-stage six-blade stirrer was attached, and the mixture was further stirred for 27 minutes to obtain a prepolymer solution. Then, p-tert-butylphenol 20.
50 m of a dichloromethane solution containing 7 g (3.44 mol% based on bisphenol A) and 0.32 g triethylamine (0.08 mol% based on bisphenol A)
1 was added and stirred for 30 minutes to terminate the reaction. Subsequent operations were performed in the same manner as in Example 1 to obtain an aromatic polycarbonate powder.

Example 4 A 10-liter baffled flask was equipped with a three-stage, six-blade stirrer and a reflux condenser. To this flask, 912 g (4.0 mol) of bisphenol A, 4 liters of dichloromethane and 4 liters of water were placed, and a nitrogen purge was performed to remove oxygen in the flask. Next, 1.5 liter of an aqueous solution of 1.8 g of sodium hydrosulfite and 442 g (11.04 mol) of sodium hydroxide was supplied to the above suspension, and bisphenol A was dissolved at 15 ° C. 471 g of phosgene in this mixture with stirring
(4.76 mol) was supplied for 30 minutes to obtain an oligomer solution. Next, the 3-stage, 6-blade stirrer was removed, an SL-type homomixer was attached instead, and the mixture was stirred at 6000 rpm for 3 minutes to obtain a highly emulsified state. Then, without stirring as it is, the interfacial polymerization reaction is carried out for 57 minutes while still standing,
A prepolymer solution was obtained. Then, 20.7 g of p-tert-butylphenol (for bisphenol A, 3.
44 mol%) and 0.32 g of triethylamine (0.08 mol% based on bisphenol A) in 50 ml of dichloromethane were added, and the mixture was stirred at 6000 rpm for 3 minutes, and then left standing for 27 minutes without stirring. An interfacial polymerization reaction was performed to terminate the reaction. Subsequent operations were performed in the same manner as in Example 1 to obtain an aromatic polycarbonate powder.

Example 5 An SL type homomixer and a reflux condenser were attached to a 10-liter baffled flask. In this flask,
Bisphenol A (438 g, 1.92 mol) and 3 liters of water were added, and a nitrogen purge was performed to remove oxygen in the flask. Next, 1.8 g of sodium hydrosulfite and 192 g of sodium hydroxide were added to the above suspension.
15 liters of an aqueous solution of (4.8 mol) was added,
The bisphenol A was dissolved at ℃. To this mixture, with stirring, 735 g of bischloroformate of bisphenol A
4 liters of a dichloromethane solution in which (2.08 mol) was dissolved was added to obtain an oligomer solution. Then 1000
The mixture was stirred at 0 rpm for 2 minutes to obtain a highly emulsified state, and allowed to stand for 58 minutes without performing stirring to carry out interfacial polymerization to obtain a prepolymer solution. Then, p-tert-butylphenol 2
50 ml of a solution of 0.7 g (3.44 mol% with respect to bisphenol A) in dichloromethane was added. Then, the mixture was again stirred at 10,000 rpm for 2 minutes to obtain a highly emulsified state, and allowed to stand for 28 minutes without stirring to allow interfacial polymerization to terminate the reaction. Subsequent operations were performed in the same manner as in Example 1 to obtain an aromatic polycarbonate powder.

Example 6 In Example 5, p-tert-butylphenol 20.
Instead of using 7 g (3.44 mol% relative to bisphenol A) 22.9 p-tert-butylphenol
A powder of aromatic polycarbonate was prepared in the same manner as in Example 5 except that g (3.80 mol% based on bisphenol A) and 0.32 g (0.08 mol% based on bisphenol A) of triethylamine were used. Got the body

Example 7 A tank-type continuous reaction apparatus was used in which four baffled flasks equipped with a reflux condenser were connected in series by an overflow outlet. The first tank, the third tank and the fourth tank have a capacity of 5 liters, a three-stage six-blade stirrer is installed, the second tank has a capacity of 0.5 liter, and an SL-type homomixer is installed. It was While stirring, in the first tank, 3653 g (16 mol) of bisphenol A, 1746 g (43.65 mol) of sodium hydroxide, and 7.2 g of sodium hydrosulfite were dissolved in 18 kg of water, an aqueous solution having a total weight of 23.4 kg, and phosgene. , And dichloromethane at 97.50 g / min and 7.78 g / min (0.
(0786 mol / min), 88.67 g / min. After a residence time of about 37 minutes, the oligomer solution was placed in the second tank 19 times.
It was discharged at a rate of 4.0 g / min. From the time when the second tank was filled with the oligomer solution, the SL type homomixer was set to 50
It was rotated at 00 rpm and stirring was started. In the second tank, after a residence time of about 4 minutes, the reaction mixture was discharged into the third tank, and in the third tank, after the same residence time as the first tank, the prepolymer solution was discharged into the fourth tank. From the time when the discharge to the fourth tank started, 180 ml of a dichloromethane solution containing 62.0 g (0.413 mol) of p-tert-butylphenol and 0.97 g (0.0096 mol) of triethylamine was added to the fourth tank at 1 ml / ml. Supplied in minutes. First in the fourth tank
After the same residence time as the tank, the reaction mixture containing the aromatic polycarbonate was discharged. When the supply of p-tert-butylphenol was started, the weight average molecular weight of the prepolymer discharged from the third tank was measured, and the results are shown in Table 1. Continuous operation was performed for 4 hours from the time when the supply to the first tank was started. During that time, when the weight average molecular weights of the prepolymer and the aromatic polycarbonate continuously discharged from the third tank and the fourth tank were measured every 30 minutes, the same result was always obtained and stable. Then, the reaction mixture discharged from the fourth tank was separated, the aqueous phase was removed, the organic phase was neutralized with hydrochloric acid, and washed repeatedly with water until the electrolyte was exhausted. To the obtained dichloromethane solution of aromatic polycarbonate, 5 liters of toluene and 12.5 liters of water were added and heated to 98 ° C. to distill off dichloromethane and toluene to obtain a powder of aromatic polycarbonate.

Example 8 A continuous reaction apparatus was used in which the first tank, the second tank, the first tube reactor, the third tank, and the second tube reactor were connected in this order through an overflow outlet. did. The first tank was a 5 liter baffled flask equipped with a three-stage six-blade stirrer and a reflux condenser, and the second tank and the third tank were equipped with an SL homomixer and a reflux condenser. It is a 0.5-liter flask, and the first tubular reactor and the second tubular reactor are tubular reactors having an inner diameter of 4 cm and a total length of 4 m. Under stirring, in the first tank, bisphenol A365
3 g (16 mol), sodium hydroxide 1746 g (4
3.65 mol), sodium hydrosulfite 7.
2 g of an aqueous solution having a total weight of 23.4 kg dissolved in 18 kg of water, phosgene and dichloromethane were respectively added to 97.
50 g / min, 7.78 g / min (0.0786 mol / min)
Min), 88.67 g / min. After a residence time of about 37 minutes, the oligomer solution was discharged into the second tank at a rate of 194.0 g / min. From the time when the second tank was filled with the oligomer solution, the SL-type homomixer was rotated at 5000 rpm to start stirring. After a residence time of about 4 minutes in the second tank, the reaction mixture was discharged into the first tubular reactor. In the first tubular reactor, after the same residence time as the first tank,
The prepolymer solution was discharged into the third tank. From the time when the discharge to the third tank started, 180 ml of a dichloromethane solution containing 62.0 g (0.413 mol) of p-tert-butylphenol was supplied to the third tank at 1 ml / min. From the time when the third tank was filled with the prepolymer solution, the SL-type homomixer was rotated at 5000 rpm to start stirring.
After a residence time of about 4 minutes in the third tank, the reaction mixture was discharged into the second tubular reactor. In the second tubular reactor, the reaction mixture containing aromatic polycarbonate was discharged after the same residence time as in the first tank. The weight average molecular weight of the prepolymer discharged from the first tubular reactor was measured when the supply of p-tert-butylphenol was started, and the results are shown in Table 1. 4 from the time when the supply to the first tank was started
It was operated continuously for hours. Meanwhile, the first tubular reactor and the second tubular reactor
When the weight average molecular weights of the prepolymer and the aromatic polycarbonate continuously discharged from the tubular reactor were measured every 30 minutes, the same result was always obtained and stable. Subsequent operations were performed in the same manner as in Example 7 to obtain an aromatic polycarbonate powder.

Comparative Example 1 (US Pat. No. 3,275,601)
No. 3) A 10-liter baffled flask was equipped with a three-stage six-blade stirrer and a reflux condenser. In this flask, 912 g of bisphenol A (4.0 mol), p-te
20.7 g of rt-butylphenol (3.44 mol% with respect to bisphenol A), 4 liters of dichloromethane and 4 liters of water were added, and a nitrogen purge was performed to remove oxygen in the flask. Next, 1.5 liter of an aqueous solution of 1.8 g of sodium hydrosulfite and 436 g (10.91 mol) of sodium hydroxide was supplied to the above suspension, and bisphenol A was dissolved at 15 ° C. To this mixture, with stirring, 467 g (4.72 mol) of phosgene
For 30 minutes. Then, triethylamine 0.
32 g (0.08 mol% relative to bisphenol A) was added and stirred for 60 minutes to terminate the reaction. Subsequent operations were performed in the same manner as in Example 1 to obtain an aromatic polycarbonate powder.

Comparative Example 2 (Method described in JP-B-37-2198) A 10-liter baffled flask was equipped with a three-stage six-blade stirrer and a reflux condenser. Into this flask were placed 684 g (3.0 mol) of bisphenol A, 1.8 liters of dichloromethane and 2.1 liters of water,
A nitrogen purge was performed to remove oxygen in the flask.
Next, 1 liter of an aqueous solution of 1.8 g of sodium hydrosulfite and 336 g (8.4 mol) of sodium hydroxide was supplied to the above suspension, and bisphenol A was dissolved at 15 ° C. Add phosgene 33 to this mixture with stirring.
6 g (3.4 mol) were fed in 50 minutes. Next, 1 part of the reaction mixture was taken out into a beaker and stirred at 10000 rpm for 1 minute using a SL type homomixer to obtain a highly emulsified state. Return this emulsion to the flask,
Then, the mixture was again stirred with a three-stage six-blade stirrer for 2 hours. Subsequent operations were performed in the same manner as in Example 1 to obtain an aromatic polycarbonate powder.

Comparative Example 3 (Method described in JP-A-62-89723) A 10-liter baffled flask was equipped with a three-stage six-blade stirrer and a reflux condenser. 1115 g (4.88 mol) of bisphenol A and 3.38 liter of dichloromethane were placed in this flask, and a nitrogen purge was performed to remove oxygen in the flask. Next, to the above suspension, 535 g of sodium hydroxide (13.4 mol)
5 liters of the aqueous solution of was added to dissolve bisphenol A. 560 g of phosgene (5.
66 mol) was fed in 90 minutes. Reaction temperature is 25 ± 1
It was ℃. Then p-tert-butylphenol 18.
Aqueous solution 30 of 8 g (2.57 mol% relative to bisphenol A) and 6 g (0.15 mol) of sodium hydroxide
0 ml was added. Table 1 shows the weight average molecular weight of the prepolymer at the first addition of the terminal blocking agent. Next, using an SL type homomixer, the rotation speed is 8000 rp
The mixture was stirred for 2 minutes at m to obtain a highly emulsified state. Then, the mixture is again stirred for 20 minutes by a three-stage, six-blade stirrer, and then p
-Tert-Butylphenol 14.1 g (1.92 mol% relative to bisphenol A) in dichloromethane 10
The reaction was terminated by adding 0 ml and stirring for 110 minutes. Subsequent operations were performed in the same manner as in Example 1 to obtain an aromatic polycarbonate powder.

Comparative Example 4 (Method described in JP-A-2-133425) A 10-liter baffled flask was equipped with a three-stage six-blade stirrer and a reflux condenser. To this flask, 912 g (4.0 mol) of bisphenol A, 4 liters of dichloromethane and 4 liters of water were placed, and a nitrogen purge was performed to remove oxygen in the flask. next,
Sodium hydrosulfite 1.8 was added to the above suspension.
g and 2.3 g of an aqueous solution of 400 g (10 mol) of sodium hydroxide were supplied to dissolve bisphenol A. To this mixture, with stirring, 468 g (4.7 g) of phosgene.
3 mol) in 90 minutes. Next, 0.5 liter of a solution of 20.4 g of p-tert-butylphenol (3.39 mol% based on bisphenol A) in dichloromethane and 1.5 liter of an aqueous solution of 96 g of sodium hydroxide were added. Next, using an SL type homomixer, the mixture was stirred at a rotation speed of 6000 rpm for 3 minutes to obtain a highly emulsified state. Then, the mixture was again stirred for 60 minutes with a three-stage, six-blade stirrer. The weight average molecular weight at that time was 41,000 (75% of the target). At that time, 0.4 g of triethylamine (0.1 mol% based on bisphenol A)
10 ml of an aqueous solution of was added and stirred for a further 60 minutes to terminate the reaction. Subsequent operations were performed in the same manner as in Example 1 to obtain an aromatic polycarbonate powder.

Comparative Example 5 (Method described in JP-A-4-277521) A 10-liter baffled flask was equipped with a three-stage six-blade stirrer and a reflux condenser. In this flask, 912 g (4 mol) of bisphenol A, 2.1 g of sodium hydrosulfite, 43 sodium hydroxide
8 g (10.95 mol), and dichloromethane 2.8
1 liter was charged and 4 liters of water was added and dissolved.
With stirring, 459 g (4.64 mol) of phosgene was fed to this mixture in 90 minutes. The reaction temperature was 25 ± 1 ° C. Next, 16.67 g of p-tert-butylphenol
(2.78 mol% with respect to bisphenol A) and 3.2 g (0.08 mol) of sodium hydroxide in water 2
50 ml was added. Then, the mixture was stirred for 2 minutes at a rotation speed of 8000 rpm by an SL type homomixer to obtain a highly emulsified state, and the mixture was kept at 30 ± 1 ° C. without stirring as it was and left standing for 2 hours to terminate the reaction. Subsequent operations were performed in the same manner as in Example 1 to obtain an aromatic polycarbonate powder.

In Table 1, the weight average molecular weight (Mw) of the prepolymer at the time of adding the end-capping agent in each Example and each Comparative Example, and the weight of the prepolymer with respect to the weight average molecular weight of the obtained aromatic polycarbonate. The arrival rate (%) of the average molecular weight is shown. In Table 2 (Table 2), the weight average molecular weight (Mw) after the completion of the polymerization, the molecular weight distribution [the ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn), and the smaller Mw / Mn, the narrower the molecular weight distribution is. ], Molecular weight 3000
The following low molecular weight oligomer contents (% by weight) and glass transition points (Tg, ° C) are shown. The measuring method is as shown below. -Measurement of weight average molecular weight, reaching rate, molecular weight distribution and content of low molecular weight oligomers: After allowing the reaction mixture to stand, separating the organic phase, neutralizing with hydrochloric acid, and washing with water until the electrolyte disappears, Dichloromethane is distilled off to obtain a prepolymer or an aromatic polycarbonate. 0.02 g of the obtained prepolymer or aromatic polycarbonate is dissolved in 10 g of chloroform. This solution is measured by GPC [gel permeation chromatography, Showa Denko KK-made, GPC system-11].
For the prepolymer, the weight average molecular weight (Mw) and the achievement rate (%) were calculated. For aromatic polycarbonates, weight average molecular weight (Mw), molecular weight distribution (Mw)
/ Mn) and the content (% by weight) of the low molecular weight oligomer having a molecular weight of 3000 or less were calculated. -Glass transition point (Tg, ° C): Using DSC [manufactured by Mac Science Co., Ltd., DSC-3100], the temperature rising rate was measured under the condition of 16 ° C / min.

[0058]

[Table 1]

[0059]

[Table 2]

From Examples 1 to 8, it can be seen that the production method of the present invention can suitably produce an aromatic polycarbonate having a low content of low molecular weight oligomers, a narrow molecular weight distribution, and excellent heat resistance. Moreover, in order to produce an aromatic polycarbonate having a low content of low-molecular weight oligomers and a narrow molecular weight distribution as compared with Examples 1 to 8 and Comparative Examples 1 and 3 to 5, in order to produce an aromatic polycarbonate, It turns out that the timing of addition is very important. In addition, it can be seen from Examples 7 and 8 that the production method of the present invention can be preferably carried out using a continuous reaction apparatus. It can be seen that the production method of Comparative Example 2 does not reach the target weight average molecular weight. It is understood that the conventional production methods of Comparative Examples 1 to 5 can produce only aromatic polycarbonate having a large content of low molecular weight oligomers and a wide molecular weight distribution. From the above results, according to the production method of the present invention, it is possible to produce an aromatic polycarbonate having a low content of low-molecular weight oligomers, a narrow molecular weight distribution, and excellent heat resistance as compared with conventional production methods. Became.

[0061]

According to the present invention, it is possible to provide an aromatic polycarbonate having a low content of low molecular weight oligomer and a narrow molecular weight distribution.

 ─────────────────────────────────────────────────── (72) Inventor Masakatsu Nakatsuka 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd. (72) Akihiro Yamaguchi 1190 Kasama-cho, Sakae-ku, Yokohama, Kanagawa Mitsui Toatsu Chemical Within the corporation

Claims (4)

[Claims] 1. In a reaction system containing at least one aromatic dihydroxy compound, a carbonate precursor, an alkali metal or alkaline earth metal base, water and an organic solvent, the absence of (A) an end capping agent and a polycarbonate generation catalyst. An interfacial polymerization reaction is performed below to form an oligomer, and (B) the oligomer is interfused in an emulsified state until the weight average molecular weight of the prepolymer becomes 20 to 99% of the weight average molecular weight of the obtained aromatic polycarbonate. A method for producing an aromatic polycarbonate comprising the steps of continuing a polymerization reaction to form a prepolymer, (C) then adding an end-capping agent, and further performing an interfacial polymerization reaction. 2. The production method according to claim 1, wherein the interfacial polymerization reaction of the step (C) is carried out in an emulsified state. 3. The production method according to claim 1, wherein the interfacial polymerization reaction of step (C) is carried out in the presence of a polycarbonate-forming catalyst. 4. An aromatic polycarbonate obtained by the method according to claim 1.