JPH09188753A - Method for producing polycarbonate - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide a method capable of improving the reaction rate, removing the catalyst by thermal decomposition at the final stage of the reaction, and efficiently producing a polycarbonate of excellent quality. . A In producing the polycarbonate by transesterification, as a polymerization catalyst, the general formula ^{(I) ((R 1 -Ph} ) n -PPh (4-n)) + (X 1) - ··· (I [Wherein R ¹ represents an organic group and may be the same or different from each other, X ¹ halogen atom, hydroxyl group, alkyloxy group, aryloxy group, alkylcarboxyl group, arylcarboxyl group or BR ₄ (R is A hydrogen atom or a hydrocarbon group, four Rs may be the same or different, Ph represents a phenyl group, and n is 1 to
Indicates an integer of 4. ] It is a manufacturing method of the polycarbonate characterized by using the quaternary phosphonium compound represented by these.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing polycarbonate. Specifically, for example, when a polycarbonate is produced by a transesterification reaction using a dihydroxy compound and a carbonic acid diester as raw materials, the reaction rate can be increased by using a quaternary phosphonium compound represented by the general formula (I) as a polymerization catalyst. And a catalyst capable of removing the catalyst by thermal decomposition at the final stage of the reaction and capable of efficiently producing a polycarbonate of excellent quality.

[0002]

2. Description of the Related Art Polycarbonate (hereinafter sometimes abbreviated as "PC") is an engineering plastic excellent in transparency, heat resistance or impact resistance, and is currently used in electric and electronic fields, automobile fields, Widely used in the optical component field and other industrial fields. As a method for producing a polycarbonate having the above characteristics, a method of directly reacting an aromatic dihydroxy compound and phosgene (interfacial polycondensation method), or a method of transesterifying an aromatic dihydroxy compound and diphenyl carbonate in a molten state (Melt polymerization method), a method of performing the latter stage of the reaction in a solid state (solid phase polymerization method: Japanese Patent Application No. 5-18257, expanded solid phase polymerization method: Japanese Patent Application No. 7-17230) and the like are known. In such a PC manufacturing method, the interfacial polycondensation method requires that toxic phosgene be used, that the manufacturing equipment is corroded by chlorine-containing compounds such as hydrogen chloride and sodium chloride produced as a by-product, and is mixed into the resin. Since there are various problems such as difficulty in separating impurities that adversely affect the physical properties of polymers such as sodium hydroxide, improvement of the production method has been desired. In order to solve this problem, recently, the melt polymerization method utilizing the transesterification reaction between a dihydroxy compound and a carbonic acid diester has been actively developed.

In the above-mentioned melt polymerization method, a basic catalyst such as a hydroxide, carbonate or acetate of an alkali metal or an alkaline earth metal is usually used as a polymerization catalyst. Further, in recent years, for example, a method of using a nitrogen-containing basic compound and an alkali metal or alkaline earth metal catalyst described in JP-A-2-124934, or an electron donation described in JP-A-5-1145. A method of using a catalyst consisting of a reactive amine and a compound containing an element of Group IIb, Ib, or Vb of the periodic table is disclosed,
Research on new catalyst systems is also very active. However, if a catalyst such as an alkali metal or an alkaline earth metal remains in the final product, polycarbonate, there is a problem that the physical properties such as heat resistance and hydrolysis resistance are deteriorated.

To solve this problem, for example, Japanese Patent Application Laid-Open No. 4-175368 discloses a method of neutralizing the polymerization catalyst by adding an acidic substance to the reaction system at the end of the polymerization. However, the method disclosed herein has problems such as the need to further detoxify the excess acidic substance used for neutralization, and cannot be said to be a sufficiently satisfactory method. Further, JP-A-4-296325 describes a method of using an electron donating amine compound as a catalyst without using an alkali metal or an alkaline earth metal. However, under a high temperature of 280 to 310 ° C. and a reduced pressure of 1 mmHg, the electron-donating amine compound is distilled off from the reaction system, and no satisfactory activity can be obtained, or a large amount of catalyst must be used. There are problems such as these, and it is hard to say that this is a sufficient method.

[0005]

DISCLOSURE OF THE INVENTION The present invention can improve the drawbacks of the conventional method for producing a polycarbonate by a transesterification reaction, improve the reaction rate, and improve heat resistance and hydrolysis resistance. It is an object of the present invention to provide a method for efficiently producing an excellent high quality polycarbonate.

[0006]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present inventors efficiently produced a polycarbonate having excellent heat resistance and hydrolysis resistance while improving the reaction rate in the transesterification method. We have earnestly studied to develop a method that can do it. As a result, by using the quaternary phosphonium compound represented by the general formula (I) as a catalyst, stable activity is exhibited in the transesterification reaction, and thermal decomposition is possible at the final stage of the reaction, resulting in deterioration of polymer quality. It has been found that the above problems can be solved without causing the above problems. The present invention has been completed based on such findings. That, when the present invention is to produce a polycarbonate by transesterification, as a polymerization catalyst, the general formula ^{(I) ((R 1 -Ph} ) n -PPh (4-n)) + (X 1) - ··· (I) [In the formula, R ¹ represents an organic group, which may be the same or different from each other, X ¹ is a halogen atom, a hydroxyl group, an alkyloxy group, an aryloxy group, an alkylcarboxyl group,
Represents an arylcarboxyl group or BR ₄ (R represents a hydrogen atom or a hydrocarbon group, and four Rs may be the same or different from each other), Ph represents a phenyl group, and n represents 1
Shows an integer of ~ 4. ] The quaternary phosphonium compound represented by these is used, The manufacturing method of the polycarbonate characterized by the above-mentioned is provided. Here, the raw materials for the transesterification reaction are preferably (A) dihydroxy compound and (B) carbonic acid diester, and after the transesterification reaction, it is preferable to heat-treat the reaction product at a temperature not lower than the decomposition temperature of the catalyst.

[0007]

DETAILED DESCRIPTION OF THE INVENTION In the present invention, a polycarbonate is produced by a transesterification reaction. There are no particular restrictions on the raw materials used in this transesterification method, and various materials used for production by a normal transesterification method are used. For example, in the transesterification reaction, a dihydroxy compound is used as the component (A), a diester carbonate is used as the component (B), a diester of a dihydroxy compound is used as the component (A), a diester carbonate is used as the component (B), and a dihydroxy compound is used as the component (A). Examples of the carbonate and the component (B) include diester carbonate, dicarbonate of a dihydroxy compound (self-condensation), and monocarbonate of a dihydroxy compound (self-esterification). Among these,
A dihydroxy compound is preferably used as the component (A) and a diester carbonate is used as the component (B).

The dihydroxy compound as the component (A) preferably used in the transesterification reaction is, for example, an aromatic dihydroxy compound or an aliphatic dihydroxy compound, and is at least one compound selected from these. The aromatic dihydroxy compound used as one of the components (A) has the general formula (II)

[0009]

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Compounds represented by the following formulas can be mentioned.
In the general formula (II), R ³ and R ⁴ are each a halogen atom of fluorine, chlorine, bromine, iodine or an alkyl group having 1 to 8 carbon atoms, such as a methyl group, an ethyl group, and n-.
Propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, pentyl,
It represents a hexyl group, a cyclohexyl group, a hebutyl group, an octyl group, or the like. R ³ and R ⁴ may be the same or different. The plurality of R ³ when there are a plurality of R ³ may be the same or different, a plurality of R ⁴ if R ⁴ there are a plurality may be the same or different. m and n are each an integer of 0-4. Z is a single bond, an alkylene group having 1 to 8 carbon atoms, an alkylidene group having 2 to 8 carbon atoms, a cycloalkylene group having 5 to 15 carbon atoms, a cycloalkylidene group having 5 to 15 carbon atoms, or -S-, −
_{SO -, - SO 2 -,} - O -, - CO- bond or formula (III), (III ')

[0011]

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[0012] The bond represented by Examples of the alkylene group having 1 to 8 carbon atoms and the alkylidene group having 2 to 8 carbon atoms include:
Examples thereof include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, an ethylidene group, an isopropylidene group and the like. As a cycloalkylene group having 5 to 15 carbon atoms and a cycloalkylidene group having 5 to 15 carbon atoms, Examples thereof include a cyclopentylene group, a cyclohexylene group, a cyclopentylidene group, and a cyclohexylidene group.

Examples of the aromatic dihydroxy compound represented by the above general formula (II) include bis (4-hydroxyphenyl) methane; bis (3-methyl-4-hydroxyphenyl) methane; bis (3-chloro-4). -Hydroxyphenyl) methane; bis (3,5-dibromo-4-hydroxyphenyl) methane; 1,1-bis (4-hydroxyphenyl) ethane; 1,1-bis (2-t-butyl-4)
-Hydroxy-3-methylphenyl) ethane; 1,1-
Bis (2-t-butyl-4-hydroxy-3-methylphenyl) ethane; 1-phenyl-1,1-bis (3-fluoro-4-hydroxy-3-methylphenyl) ethane; 2,2-bis ( 4-hydroxyphenyl) propane (commonly known as bisphenol A); 2,2-bis (3-methyl-4-hydroxyphenyl) propane; 2,2-bis (2-methyl-4-hydroxyphenyl) propane;
2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane; 1,1-bis (2-t-butyl-4-
Hydroxy-5-methylphenyl) propane; 2,2-
Bis (3-chloro-4-hydroxyphenyl) propane; 2,2-bis (3-fluoro-4-hydroxyphenyl) propane; 2,2-bis (3-bromo-4-hydroxyphenyl) propane; 2,2 -Bis (3,5-difluoro-4-hydroxyphenyl) propane; 2,2
-Bis (3,5-dichloro-4-hydroxyphenyl)
Propane; 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane; 2,2-bis (4-hydroxyphenyl) butane; 2,2-bis (4-hydroxyphenyl) octane; 2,2 -Bis (4-hydroxyphenyl) phenylmethane; 2,2-bis (4-hydroxy-1-methylphenyl) propane; 1,1-bis (4
-Hydroxy-t-butylphenyl) propane; 2,2
-Bis (4-hydroxy-3-bromophenyl) propane; 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane; 2,2-bis (4-hydroxy-
3-chlorophenyl) propane; 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane; 2,
2-bis (4-hydroxy-3,5-dibromophenyl) propane; 2,2-bis (3-bromo-4-hydroxy-5-chlorophenyl) propane; 2,2-bis (3-phenyl-4-hydroxy Phenyl) propane;
2,2-bis (4-hydroxyphenyl) butane; 2,
2-bis (3-methyl-4-hydroxyphenyl) butane; 1,1-bis (2-butyl-4-hydroxy-5-
1,1-bis (2-t-butyl-4-hydroxy-5-methylphenyl) butane;
1,1-bis (2-t-butyl-4-hydroxy-5-
Methylphenyl) isobutane; 1,1-bis (2-t-
Amyl-4-hydroxy-5-methylphenyl) butane; 2,2-bis (3,5-dichloro-4-hydroxyphenyl) butane; 2,2-bis (3,5-dibromo-
4-hydroxyphenyl) butane; 4,4-bis (4-
Hydroxyphenyl) heptane; 1,1-bis (2-t
-Butyl-4-hydroxy-5-methylphenyl) heptane; 2,2-bis (4-hydroxyphenyl) octane; bis (hydroxyaryl) alkanes such as 1,1- (4-hydroxyphenyl) ethane; 1-bis (4-hydroxyphenyl) cyclopentane; 1,1-
Bis (4-hydroxyphenyl) cyclohexane; 1,
1-bis (3-methyl-4-hydroxyphenyl) cyclohexane; 1,1-bis (3-cyclohexyl-4-)
1,1-bis (3-phenyl-4-hydroxyphenyl) cyclohexane; 1,1-bis (4-hydroxyphenyl) -3,
Bis (hydroxyaryl) cycloalkanes such as 5,5-trimethylcyclohexane; bis (4-hydroxyphenyl) ether; bis (4, -hydroxy-3-
Bis (hydroxyaryl) ethers such as methylphenyl) ether; bis (4-hydroxyphenyl) sulfide; bis (hydroxyaryl) sulfides such as bis (3-methyl-4-hydroxyphenyl) sulfide; bis (4-hydroxy Bis (3-methyl-4-hydroxyphenyl) sulfoxide; bis (hydroxyaryl) sulfoxides such as bis (3-phenyl-4-hydroxyphenyl) sulfoxide; bis (4hydroxyphenyl) sulfone; bis (3 -Methyl-4-hydroxyphenyl) sulfone; bis (3-phenyl-4-hydroxyphenyl)
Bis (hydroxyaryl) sulfones such as sulfone, 4,4′-dihydroxybiphenyl; 4,4′-dihydroxy-2,2′-dimethylbiphenyl; 4,4 ′
-Dihydroxy-3,3'-dimethylbiphenyl; 4,
4′-dihydroxy-3,3′-dicyclohexylbiphenyl; dihydroxybiphenyls such as 3,3′-difluoro-4,4′-dihydroxybiphenyl and the like.

Examples of aromatic dihydroxy compounds other than the above general formula (II) include dihydroxybenzenes, halogen- and alkyl-substituted dihydroxybenzenes.
For example, resorcin, 3-methylresorcin, 3-ethylresorcin, 3-propylresorcin, 3-butylresorcin, 3-t-butylresorcin, 3-phenylresorcin, 3-cumylresorcin; 2,3,4,6- Tetrafluororesorcin; 2,3,4,6-tetrabromoresorcin; catechol, hydroquinone, 3-methylhydroquinone, 3-ethylhydroquinone, 3-propylhydroquinone, 3-butylhydroquinone, 3
-T-butylhydroquinone, 3-phenylhydroquinone, 3-cumylhydroquinone; 2,5-dichlorohydroquinone; 2,3,5,6-tetramethylhydroquinone; 2,3,4,6-tetra-t-butylhydroquinone 2,3,5,6-tetrafluorohydroquinone; 2,3,5,6-tetrabromohydroquinone and the like.

There are various kinds of aliphatic dihydroxy compounds used as one of the component (A). For example, butane-1,4-diol; 2,2-dimethylpropane-1,3-diol; hexane-1,6-diol
Diols; diethylene glycol; triethylene glycol; tetraethylene glycol; octaethylene glycol; dipropylene glycol; N, N-methyldiethanolamine; cyclohexane-1,3-diol;
Cyclohexane-1,4-diol; 1,4-dimethylolcyclohexane; p-xylylene glycol;
Ethoxylated or propoxylated products of 2-bis- (4-hydroxycyclohexyl) -propane and dihydric alcohols or phenols, such as bis-oxyethyl-bisphenol A; bis-oxyethyl-tetrachlorobisphenol A or bis-oxyethyl-tetrachloro Hydroquinone and the like.

In a preferred production method of the present invention,
As the dihydroxy compound of the component (A), one or more of the above compounds are appropriately selected and used, and among these, bisphenol A which is an aromatic dihydroxy compound is preferably used. On the other hand, in the present invention,
There are various types of carbonate diester used as the component (B). For example, it is at least one compound selected from diaryl carbonate compounds, dialkyl carbonate compounds and alkylaryl carbonate compounds. The diaryl carbonate compound used as one of the components (B) has the general formula (IV)

[0017]

Embedded image (In the formula, Ar ¹ and Ar ² each represent an aryl group, and they may be the same or different from each other.)
Or a compound represented by the general formula (V)

[0018]

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(In the formula, Ar ³ and Ar ⁴ each represent an aryl group, which may be the same or different, and D ¹ represents a residue obtained by removing two hydroxyl groups from the aromatic dihydroxy compound. ). The dialkyl carbonate compound has the general formula (VI)

[0020]

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(In the formula, R ⁵ and R ⁶ each have 1 carbon atom.
Represents an alkyl group having from 6 to 6 or a cycloalkyl group having from 4 to 7 carbon atoms, which may be the same or different. ) Or a compound represented by the general formula (VII)

[0022]

[Chemical 6]

(In the formula, each of R ⁷ and R ⁸ has 1 carbon atom.
And a cycloalkyl group having 4 to 7 carbon atoms, which may be the same or different, and D ² represents a hydroxyl group 2 from the aromatic dihydroxy compound.
The residue excluding the number is shown. ). The alkyl aryl carbonate compound has the general formula (VIII)

[0024]

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(Wherein Ar ⁵ represents an aryl group, R ⁹ represents an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 4 to 7 carbon atoms), or a general formula (IX)

[0026]

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(Wherein Ar ⁶ is an aryl group, R ¹⁰ is an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 4 to 7 carbon atoms, and D ³ is the above aromatic dihydroxy compound from which two hydroxyl groups have been removed. The compound represents a residue.).
Here, examples of the carbonic acid diaryl compound include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, and bisphenol A bisphenyl carbonate. Examples of the dialkyl carbonate compound include diethyl carbonate, dimethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate, and bisphenol A bismethyl carbonate.

Examples of the alkylaryl carbonate compound include, for example, methyl phenyl carbonate, ethyl phenyl carbonate, butyl phenyl carbonate, cyclohexyl phenyl carbonate, bisphenol A
Methyl phenyl carbonate and the like can be mentioned. In the present invention, one or more of the above compounds are appropriately selected and used as the diester carbonate (B), and among these, diphenyl carbonate is preferably used.

Next, as raw materials other than the dihydroxy compound and the carbonic acid diester used in the present invention,
These include: That is, examples of diesters of dihydroxy compounds include diacetate of bisphenol A, dipropionate of bisphenol A, dibutylate of bisphenol A, and dibenzoate of bisphenol A. Examples of the dicarbonate of the dihydroxy compound include bismethyl carbonate of bisphenol A, bisethyl carbonate of bisphenol A, and bisphenyl carbonate of bisphenol A. Examples of monocarbonates of the dihydroxy compound include bisphenol A monomethyl carbonate, bisphenol A monoethyl carbonate, bisphenol A monopropyl carbonate, and bisphenol A monophenyl carbonate.

In the production method of the present invention, a terminal terminator can be used if necessary. Examples of the terminal stopper include on-butylphenol; m
-N-butylphenol; pn-butylphenol;
o-isobutylphenol; m-isobutylphenol; p-isobutylphenol; ot-butylphenol; mt-butylphenol; pt-butylphenol; on-pentylphenol; m-n-pentylphenol; pn -Pentylphenol; on-
Hexylphenol; mn-hexylphenol; p
-N-hexylphenol; o-cyclohexylphenol; m-cyclohexylphenol; p-cyclohexylphenol; o-phenylphenol; m-phenylphenol; p-phenylphenol; on-nonylphenol; mn-nonylphenol; n-nonylphenol; o-cumylphenol; m-cumylphenol; p-cumylphenol; o-naphthylphenol; m-naphthylphenol; p-naphthylphenol; 2,6-di-t-butylphenol; -Ji-
t-butylphenol; 2,4-di-t-butylphenol; 3,5-di-t-butylphenol; 2,5-dicumylphenol; 3,5-dicumylphenol;

[0031]

Embedded image Or a compound represented by

[0032]

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Monovalent phenols such as chroman derivatives represented by Among such phenols,
Although not particularly limited in the present invention, pt-butylphenol, p-cumylphenol, p-phenylphenol and the like are preferable. Also, the formula

[0034]

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Compounds represented by the following formulas can also be used. Furthermore, in the present invention, if necessary, phloroglucin; trimellitic acid; 1,1,1-tris (4-hydroxyphenyl) ethane; 1- [α-methyl-α- (4 ′)
-Hydroxyphenyl) ethyl] -4- [α ', α'-
Bis (4 "-hydroxyphenyl) ethyl] benzene;
α, α ', α "-tris (4-hydroxyphenyl)-
1,3,5-triisopropylbenzene; isatin bis (o-cresol) and the like can also be used as a branching agent.

In the production method of the present invention, it is necessary to use a quaternary phosphonium compound represented by the general formula (I) as a polymerization catalyst in the transesterification reaction. Here, the general formula _{^{(I), ((R 1 -Ph) n}} -PPh (4-n)) + (X 1) - ··· (I) [In the formula, R ¹ represents an organic group, X ¹ may be the same as or different from each other, X ¹ is a halogen atom, a hydroxyl group, an alkyloxy group, an aryloxy group, an alkylcarboxyl group,
Represents an arylcarboxyl group or BR ₄ (R represents a hydrogen atom or a hydrocarbon group, and four Rs may be the same or different from each other), Ph represents a phenyl group, and n represents 1
Shows an integer of ~ 4. ] Is represented. Examples of such a quaternary phosphonium compound include biphenyltriphenylphosphonium hydroxide, methoxyphenyltriphenylphosphonium hydroxide, phenoxyphenyltriphenylphosphonium hydroxide, biphenyltriphenylphosphonium tetraphenylborate and methoxyphenyltriphenylphosphonium tetraphenylborate. , Phenoxyphenyltriphenylphosphonium tetraphenylborate, biphenyltriphenylphosphonium phenoxide, methoxyphenyltriphenylphosphonium phenoxide, phenoxyphenyltriphenylphosphonium phenoxide and the like. Preferably, biphenyltriphenylphosphonium tetraphenylborate, biphenyltriphenylphosphonium phenoxide, phenoxyphenyltriphenylphosphonium tetraphenylborate, phenoxyphenyltriphenylphosphonium phenoxide, methoxyphenyltriphenylphosphonium tetraphenylborate and methoxyphenyltriphenylphosphonium phenoxide are polymerized. It is desirable from the viewpoint of improving activity, improving polymerization stability, and improving quality.

The quaternary phosphonium compound may be used alone or in combination of two or more kinds. The quaternary phosphonium compound preferably has a metal impurity content as low as possible, and particularly preferably has an alkali metal and alkaline earth metal compound content of 50 ppm or less. In the present invention, a quaternary phosphonium salt is used as a polymerization catalyst in an amount of 10 ⁻³ to 10 ⁻⁸ mol, preferably 10 ^−4.
It is desirable to use 10 ^-7 mol. If the amount of the quaternary phosphonium salt used is less than 10 ^-8 mol, the catalytic activity in the latter stage of the reaction becomes insufficient, and if it exceeds 10 ^-3 mol, it leads to an increase in cost, which is not preferable.

In the present invention, a nitrogen-containing organic basic compound may be used in combination with the quaternary phosphonium compound represented by the general formula (I). Examples of the organic base compound of the general formula _{^{(X) (NR 2 4)}} + (X 2) - ··· (X) [wherein R ² represents an organic group, from each other the same four R ² They may be different, or two R ^{2 s} may combine to form a ring structure. X ² represents a halogen atom, a hydroxyl group, an alkyloxy group, an aryloxy group or BR ₄ (R represents a hydrogen atom or a hydrocarbon group, and four Rs may be the same or different). ] The quaternary ammonium compound represented by these is mentioned.

Here, as the quaternary ammonium salt, for example, ammonium having an alkyl group such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide or trimethylbenzylammonium hydroxide, an aryl group or an araryl group. Examples thereof include basic salts such as hydroxides, tetramethylammonium borohydride, tetrabutylammonium borohydride, tetrabutylammonium tetraphenylborate, and tetramethylammonium tetraphenylborate.
Among these quaternary ammonium salts, the catalytic activity is high,
In addition, the quaternary ammonium salt represented by the above general formula (X), which is easily decomposed by heat and hardly remains in the polymer,
Specifically, tetramethylammonium hydroxide, tetrabutylammonium hydroxide, tetramethylammonium borohydride and tetrabutylammonium borohydride are preferable, and tetramethylammonium hydroxide is particularly preferable.

Further, the nitrogen-containing organic basic compound may be an electron-donating amine or a tertiary amine. Examples of the electron-donating amine include N, N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 4-pyrrolidinopyridine, 4-piperidinopyridine, 4-aminopyridine, 2-aminopyridine, 4- Hydroxypyridine, 2-hydroxypyridine, 4-methoxypyridine,
2-methoxypyridine, imidazole, 2-methylimidazole, 4-methylimidazole, 2-methoxyimidazole, 2-mercaptoimidazole, aminoquinoline, diazabicyclooctane (DABCO) and the like can be mentioned. Examples of the tertiary amine compound include trimethylamine, triethylamine, tripropylamine,
Tributylamine, tripentylamine, trihexylamine, dimethylbenzamine, triphenylamine, 7-methyl-1,5,7-triazacyclo [4.
4.0] dec-5-ene (MTBD), 1,8-diazabicyclo [5.4.0] undecen-7-ene (DB
U), 1,5-diazabicyclo [4.3.0] non-5
-En (DBN) and the like.

When the above-mentioned polymerization catalyst is used,
The component (a) is a quaternary phosphonium compound with respect to 1 mol of the dihydroxy compound of the component (A) which is a raw material,
When the component (b) is a nitrogen-containing organic basic compound, (a)
The total amount of the component and the component (b) is usually added in a ratio such that it is 10 ^-1 to 10 ^-8 mol, preferably 10 ^-2 to 10 ^-7 mol. If the amount of this catalyst added is less than 10 ^-8 mol,
The catalytic effect may not be exhibited. If it exceeds 10 ^-1 mol, the physical properties of the final product polycarbonate, particularly heat resistance and hydrolysis resistance, may be reduced, and this leads to an increase in cost. There is no. The nitrogen-containing organic basic compound as the component (b) may be used alone or in combination of two or more.

In the production method of the present invention, the raw materials used for the production of polycarbonate by the usual transesterification method are used, but preferably, the dihydroxy compound as the component (A) and the carbonic acid diester as the component (B) are required. Depending on the case, a transesterification reaction may be carried out using a terminal stopper, a branching agent or the like to obtain a polycarbonate of excellent quality. Specifically, the reaction may be allowed to proceed according to a known transesterification method. Hereinafter, the procedure and conditions of the preferred production method of the present invention will be specifically described. First, the dihydroxy compound (A) and the carbonic acid diester (B) are
Carbonic acid diester is 0.9 to 1.
The transesterification reaction is performed at a ratio such that the molar ratio becomes 5 times. Note that, depending on the situation, the molar ratio is preferably 0.98 to 1.20 times.

In the above-mentioned transesterification reaction, the amount of the terminal terminator composed of the above-mentioned monohydric phenol is
It is 0.05 with respect to the dihydroxy compound which is the component (A).
When it is in the range of 10 to 10 mol%, the hydroxyl group terminal of the obtained polycarbonate is sealed, so that a polycarbonate having excellent heat resistance and water resistance can be obtained. Such a terminal terminator comprising a monohydric phenol or the like may be added in advance to the reaction system in its entirety. Alternatively, a part may be added to the reaction system in advance, and the remainder may be added as the reaction proceeds. Further, in some cases, the whole amount may be added to the reaction system after the transesterification reaction between the dihydroxy compound of component (A) and the diester carbonate of component (B) partially proceeds.

In carrying out the transesterification reaction according to the production method of the present invention, the reaction temperature is not particularly limited,
Usually in the range of 100 to 330 ° C, preferably 180 to 30 ° C.
The temperature is selected within the range of 0 ° C., and more preferably, the temperature is gradually raised to 180 to 300 ° C. in accordance with the progress of the reaction. The temperature of this transesterification reaction is 100 ° C
If the temperature is lower than 330 ° C., the reaction rate will be low. On the other hand, if the temperature exceeds 330 ° C., a problem such as side reaction will occur or the resulting polycarbonate will be colored, which is not preferable. The reaction pressure is set according to the vapor pressure of the monomer used and the reaction temperature. This may be set so that the reaction is performed efficiently, and is not limited. Usually, in the initial stage of the reaction, 1 to 50 atm (760 to 38,000)
torr) or pressurized state, and in the latter stage of the reaction, the pressure is reduced, preferably 0.01 to 100 torr in many cases. Furthermore, the reaction time may be performed until the target molecular weight is reached.
It is about 0.2 to 10 hours.

The above-mentioned transesterification reaction is usually carried out in the absence of an inert solvent, but if necessary, it may be carried out in the presence of an inert solvent in an amount of 1 to 150% by weight of the obtained polycarbonate. Good. Here, examples of the inert solvent include aromatic compounds such as diphenyl ether, halogenated diphenyl ether, benzophenone, polyphenyl ether, dichlorobenzene, and methylnaphthalene; tricyclo (5,2,10) decane, cyclooctane, and cyclodecane. And cycloalkane. If necessary, the reaction may be performed in an inert gas atmosphere. Examples of the inert gas include gases such as argon, carbon dioxide, nitrous oxide, and nitrogen, chlorofluorohydrocarbon, ethane, and propane. And alkenes such as ethylene and propylene.

Further, in the present invention, an antioxidant may be added to the reaction system, if necessary. The antioxidant is preferably a phosphorus-based antioxidant, for example, trimethyl phosphite, triethyl phosphite, tributyl phosphite, trioctyl phosphite, trinonyl phosphite, tridecyl phosphite, trioctadecyl phosphite, distearyl. Trialkyl phosphites such as pentaerythyl diphosphite, tris (2-chloroethyl) phosphite, tris (2,3-dichloropropyl) phosphite, and tricycloalkyl phosphites such as tricyclohexyl phosphite;
Triaryl phosphites such as triphenyl phosphite, tricresyl phosphite, tris (ethylphenyl) phosphite, tris (butylphenyl) phosphite, tris (nonylphenyl) phosphite, and tris (hydroxyphenyl) phosphite; Monoalkyl diaryl phosphites such as ethylhexyl diphenyl phosphite, trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, tridecyl phosphate, trioctadecyl phosphate, distearyl pentaerythrityl diphosphate, tris (2-chloroethyl) phosphate, Trialkyl phosphates such as tris (2,3-dichloropropyl) phosphate, tricyclohexyl phosphate What tricycloalkyl phosphate, triphenyl phosphate, tricresyl phosphate, tris (nonylphenyl) phosphate, 2
Triaryl phosphates such as -ethylphenyldiphenyl phosphate and the like.

In the present invention, as the reaction proceeds, phenols corresponding to the carbonic acid diester used,
Alcohols or their esters and inert solvents desorb from the reactor. These desorbed substances can be separated, purified and recycled for use, and it is preferable to have equipment for removing them. The present invention can be carried out batchwise or continuously, and any device can be used. In the case of continuous production, it is preferable to use at least two or more reactors and set the above reaction conditions. The material and structure of the reactor used in the present invention are not particularly limited, but may be any one having a normal stirring function. However, since the viscosity increases in the latter stage of the reaction, those having a high viscosity type stirring function are preferable. Further, the shape of the reactor is not limited to a tank type, and may be an extruder type reactor or the like.

In the present invention, in order to improve the quality (coloring) of the obtained polycarbonate after the completion of the transesterification reaction, the decomposition temperature of the catalyst or higher, preferably 3 or higher.
It is preferable to heat-treat the reaction product at around 00 ° C. to thermally decompose and remove the catalyst. The polycarbonate obtained as described above may be granulated as it is, or may be molded using an extruder or the like. Further, the polycarbonate obtained by the present invention includes a plasticizer, a pigment, a lubricant,
Well-known additives such as a release agent, a stabilizer, an inorganic filler, etc. can be blended and used. In addition, the polycarbonate can be blended with polymers such as polyolefins, polystyrenes, polyesters, polysulfonates, polyamides, polyphenylene ethers and the like. In particular, it is effective to use in combination with polyphenylene ether, polyether nitrile, terminal-modified polysiloxane compound, modified polypropylene, modified polystyrene or the like having OH group, COOH group, NH ₂ group or the like at the terminal.

[0049]

Next, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples. Examples 1 to 4, Comparative Examples 1 to 4 Bisphenol A (BPA) 2 was added to a nickel steel autoclave (with a stirrer) having an internal volume of 100 ml.
2.8g (0.1mol) and diphenyl carbonate 23.5g
(1.1 mol) was added. As the catalyst, the types and amounts of the catalysts shown in Table 1 were added, and nitrogen substitution was performed 5 times.
The mixture was heated to 180 ° C. and reacted for 30 minutes under an argon atmosphere. Then, the temperature was raised to 210 ° C., the degree of vacuum was gradually raised to 100 mmHg and reacted for 30 minutes, further raised to 240 ° C., gradually raised to 10 mmHg and reacted for 30 minutes. After further increasing the temperature to 270 ° C. and the vacuum degree to 2 mmHg and reacting for 30 minutes, the temperature is 290 ° C. and the vacuum degree is 0.3 mmHg for 30 minutes.
The reaction was terminated. Next, the viscosity average molecular weight of the viscous, colorless and transparent condensate was determined in the autoclave. In addition, the condensate was press-molded to form a plate having a thickness of 1 mm and a diameter of 10 mn, and the plate was exposed to steam at 121 ° C. for 48 hours to obtain a decrease in appearance and viscosity average molecular weight to evaluate steam resistance. did. The results are shown in Table 1. The above viscosity average molecular weight was calculated using the following formula. [Η] = 1.23 × 10 ^-4 Mv ^0.83

[0050]

[Table 1] [Note] BPTB: Biphenyltriphenylphosphonium tetraphenylborate (Na, Ca, K <1 ppm) BPPO: Biphenyltriphenylphosphonium phenoxide (Na, Ca, K <1 ppm) POPTB: Phenoxyphenyltriphenylphosphonium tetraphenylborate (Na, Ca, K <1pp
m) MOPTB: methoxyphenyltriphenylphosphonium tetraphenylborate (Na, Ca, K <1pp
m) TPTB: Tetraphenylphosphonium tetraphenylborate (Na, Ca, K <1 ppm) MTPTB: Methyltriphenylphosphonium tetraphenylborate (Na <7 ppm, Mg <1 ppm) POPPO: Phenoxyphenyltriphenylphosphonium phenoxide (Na, Ca, K <1 ppm) MOPPO: methoxyphenyl triphenylphosphonium phenoxide (Na, Ca, K <1 ppm)

[0051]

According to the present invention, in the production of polycarbonate by transesterification, as a polymerization catalyst,
By using the quaternary phosphonium salt represented by the general formula (I), the catalytic activity is sufficiently high, the reaction rate can be improved, and the catalyst can be removed by thermal decomposition in the final stage of the reaction. Thus, it is possible to efficiently produce a polycarbonate of excellent quality.

Claims (6)

[Claims] Upon 1. A producing polycarbonate by transesterification, as a polymerization catalyst, the general formula ^{(I) ((R 1 -Ph} ) n -PPh (4-n)) + (X 1) - ··· ( I) [In the formula, R ¹ represents an organic group, which may be the same or different from each other, X ¹ is a halogen atom, a hydroxyl group, an alkyloxy group, an aryloxy group, an alkylcarboxyl group,
Represents an arylcarboxyl group or BR ₄ (R represents a hydrogen atom or a hydrocarbon group, and four Rs may be the same or different from each other), Ph represents a phenyl group, and n represents 1
Shows an integer of ~ 4. ] The manufacturing method of the polycarbonate characterized by using the quaternary phosphonium compound represented by these. 2. When producing a polycarbonate by a transesterification reaction, as a polymerization catalyst, biphenyltriphenylphosphonium tetraphenylborate, biphenyltriphenylphosphonium phenoxide, phenoxyphenyltriphenylphosphonium tetraphenylborate, phenoxyphenyltriphenylphosphonium phenoxide, methoxy. A method for producing a polycarbonate using at least one quaternary phosphonium compound selected from the group consisting of phenyltriphenylphosphonium tetraphenylborate and methoxyphenyltriphenylphosphonium phenoxide. 3. The method for producing a polycarbonate according to claim 1, wherein the raw materials for the transesterification reaction are (A) a dihydroxy compound and (B) a carbonic acid diester. 4. The method for producing a polycarbonate according to claim 3, wherein the dihydroxy compound as the component (A) is 2,2-bis (4-hydroxyphenyl) propane. 5. The method for producing a polycarbonate according to claim 3, wherein the carbonic acid diester of the component (B) is diphenyl carbonate. 6. The method for producing a polycarbonate according to claim 1, wherein after the transesterification reaction, the reaction product is heat-treated at a temperature not lower than the decomposition temperature of the catalyst.