JPH08325375A - Production of aromatic polycarbonate - Google Patents

Abstract

PURPOSE: To produce an aromatic polycarbonate of no discoloration and reduced in chain branching and gelling at a high polymerization rate in high productivity by melt polycondensation between an aromatic dihydroxy compound and a carbonic diester in the presence of a specific catalyst. CONSTITUTION: The melt polycondensation reaction between (A) an aromatic dihydroxy compound (suitably bis-phenol A) and (B) a carbonic diester (suitably diphenyl carbonate) are carried out in the presence of a catalyst of a quaternary ammonium of the formula (R is a l-20C alkyl, an aryl, an aralkyl) (suitably hexadecyl-trimethylammonium hydroxide or octadecyltrimethylammonium hydroxide. In a preferred embodiment, 1 mole of the component A and 1.01-1.2 mole of component B are used and the amount of the catalyst is 5×10<-6> -10<-4> mole. The catalyst is preferably charged in the reaction system in the form of a solution or suspension of 40wt.% or lower concentration. The concentration of this solution or dispersion is desirably less than 10ppm in the system.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing polycarbonate. More specifically, polymerization reaction rate, hue,
The present invention relates to a method for producing a polycarbonate having excellent heat resistance and the like.

[0002]

2. Description of the Related Art Polycarbonate is widely used because it is excellent in mechanical properties such as impact resistance, heat resistance and transparency. As a method for producing such a polycarbonate, a method of directly reacting an aromatic dihydroxy compound such as bisphenol with phosgene (interfacial method), or an aromatic dihydroxy compound such as bisphenol and a diaryl carbonate such as diphenyl carbonate in a molten state Methods such as transesterification (melting method) are known.

Among these production methods, a method for producing a polycarbonate by transesterification reaction between an aromatic dihydroxy compound and a diaryl carbonate will be explained. This method uses a metal organic acid salt, an inorganic acid salt, or a metal acid salt as a catalyst. A method in which an aromatic dihydroxy compound and a diaryl carbonate are finally heated to 250 to 330 ° C. under reduced pressure using an oxide, a hydroxide, a hydride, an alcoholate, or the like to perform a transesterification reaction while melting. is there.

This method has the advantage of being able to produce polycarbonate at a lower cost than the above-mentioned interfacial method, but on the other hand, it has the problem that the hue is unfavorable because the polymer is exposed to high temperatures for a long time. It was Various catalysts have been proposed to improve the hue, but they are still inadequate because they are inferior to polycarbonate polymerized by the interfacial method.

Tetramethylammonium hydroxide, which is one of the quaternary ammonium hydroxide compounds, is strongly basic and can serve as a transesterification catalyst for polycarbonate. However, it has decomposability and the decomposition temperature is 135-1.
Since the temperature is relatively low at 40 ° C., when melt polymerization of a polycarbonate is carried out using this compound, the polymerization activity at high temperatures is extremely low, and only a low polymer is obtained.

Japanese Unexamined Patent Publication (Kokai) No. 60-51719 proposes a method for producing a polycarbonate using a catalyst composed of a combination of a nitrogen-containing basic compound and a boron compound. Although relatively light-colored polycarbonate can be obtained by using this catalyst system, there is a problem that the polymerization activity is low.

Japanese Unexamined Patent Publication (Kokai) No. 2-124934 proposes a method for producing a polycarbonate using a catalyst composed of a combination of a nitrogen-containing basic compound, a boron compound and an alkali (earth) metal compound. When this catalyst system is used, the polymerization activity is relatively improved by the alkali (earth) metal compound, but when the alkali metal compound is used, it may be insoluble in a solvent such as methylene chloride which is considered to be due to the branched structure in the polymer depending on the reaction conditions. May produce components. The formation of insoluble matter due to the branched structure becomes more remarkable as the degree of polymerization increases.

Further, there is a case where the degree of polymerization of the obtained polycarbonate is largely lowered during molding. Further, since the resin is exposed to a high temperature atmosphere, there are problems such as coloring, insolubilization, generation of foreign matter, and reduction of molecular weight due to oxidation reaction, other decomposition reaction, and side reaction.

[0009]

The present inventor has made diligent efforts to solve the above problems, and as a result, solved the above problems by using a quaternary ammonium hydroxide compound having a specific structure. The inventors have found that the above is the case and have reached the present invention.

That is, an object of the present invention is to provide a method for producing an aromatic polycarbonate which is free from coloration and has a small amount of branching and insoluble matter by melt polycondensation. Another object of the present invention is to produce an aromatic polycarbonate in which side reactions such as branching reactions during molding are suppressed, and burns, coloring, insolubilization, formation of foreign substances or reduction in molecular weight in the molding apparatus are suppressed. To provide a method. Still another object of the present invention is to provide a method for producing the aromatic polycarbonate as described above at a high polymerization rate with high productivity. Still another object of the present invention is to provide a catalyst for producing an aromatic polycarbonate as described above. Further objects and advantages of the present invention will be apparent from the following description.

[0011]

[Means for Solving the Problems] That is, the present invention is to perform melt polycondensation of an aromatic dihydroxy compound and a carbonic acid diester in the presence of a quaternary ammonium hydroxide compound represented by the following general formula (I). And a method for producing an aromatic polycarbonate.

[0012]

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The aromatic dihydroxy compound that can be used in the present invention is not particularly limited, and examples thereof include compounds represented by the following formula (II).

[0014]

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Here, R ₃ and R ₄ are the same or different,
It is a hydrogen atom, a halogen atom or a hydrocarbon group having 1 to 12 carbon atoms. As the hydrocarbon group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms is preferable. Examples of such an aliphatic hydrocarbon group include an alkyl group, an alkenyl group and the like, and a methyl group, an ethyl group, a propyl group and the like are exemplified. Further, examples of the aromatic hydrocarbon group include a substituted or unsubstituted phenyl group and naphthyl group. Examples of the halogen atom include chlorine, bromine and iodine.

R ₅ is a divalent hydrocarbon group having 4 to 20 carbon atoms, and examples thereof include aliphatic hydrocarbon groups such as alkylene group and alkenylene group, and examples thereof include butylene group and pentylene group.

In the formula, R ₁ and R ₂ are the same or different and each is a halogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. Examples of the hydrocarbon group include an aliphatic hydrocarbon group having 1 to 12 carbon atoms and an aromatic group having 6 to 12 carbon atoms. Examples of the aliphatic hydrocarbon group include an alkyl group and an alkenyl group, and more specifically, a methyl group,
Examples thereof include ethyl group and propyl group. Further, examples of the aromatic group include a substituted or unsubstituted phenyl group and a naphthyl group. Examples of the halogen atom include chlorine, bromine and iodine.

In the formula, m and n are the same or different and each represents 0 or an integer of 1 to 4.

Specific examples include the compounds shown below. Bis (4-hydroxyphenyl) methane,
1,1-bis (4-hydroxyphenyl) ethane, 2,
2-bis (4-hydroxyphenyl) propane, 2,2
-Bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4
-Hydroxy-3-methylphenyl) propane, 1,1
-Bis (hydroxyaryl) alkanes such as bis (4-hydroxy-t-butylphenyl) propane and 2,2-bis (4-hydroxy-3-bromophenyl) propane, 1,1-bis (4-hydroxyphenyl) ) Cyclopentane, bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethylphenyl ether Dihydroxy aryl ethers such as
4,4'-dihydroxydiphenyl sulfide, 4,
Dihydroxydiarylsulfides such as 4'-dihydroxy-3,3'-dimethyldiphenylsulfide,
4,4'-dihydroxydiphenyl sulfoxide, 4,
Dihydroxy diaryl sulfoxides such as 4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide, 4,4'-dihydroxydiphenyl sulfone, 4,
Dihydroxydiarylsulfones such as 4'-dihydroxy-3,3'-dimethyldiphenylsulfone, 9,
Examples thereof include dihydroxydiaryls such as 9-bis (4-hydroxyphenyl) fluorene.

Of these, 2,2-bis (4-
Hydroxyphenyl) propane (bisphenol A) is preferably used. These aromatic dihydroxy compounds can be used alone or in combination. Bisphenol A 80-98 mol%, other components 2-2
Those containing 0 mol% can be used.

The carbonic acid diester is preferably a carbonate having an optionally substituted aryl group having 6 to 20 carbon atoms. Specific examples include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, and bis (diphenyl) carbonate. The above-mentioned diaryl carbonate is usually 1.0 to 1 mol with respect to 1 mol of the aromatic dihydroxy compound.
It is desirable to use it in an amount of 1.30 mol, preferably 1.01 to 1.20 mol.

The catalyst used in the present invention has the following general formula (I):
Is represented by

[0023]

[Chemical 4]

Examples of the alkyl group having 10 to 20 carbon atoms for R include a decyl group, a hexadecyl group, an octadecyl group, a substituted or unsubstituted phenyl group as an aryl group, and a substituted or unsubstituted benzyl group as an aralkyl group.

Specific examples include decyltrimethylammonium hydroxide, hexadecyltrimethylammonium hydroxide, octadecyltrimethylammonium hydroxide, dodecylbenzenetrimethylammonium hydroxide, dodecylbenzyltrimethylammonium hydroxide and the like.

Of these, alkyltrimethylammonium hydroxide in which R is an alkyl group in general formula (I) is preferable, and hexadecyltrimethylammonium hydroxide and octadecyltrimethylammonium hydroxide are particularly preferable. These compounds may be used alone or in combination of two or more.

[0027] As such a use amount of the catalyst, the aromatic dihydroxy compound per mol, 10 ^-6 to 10 ^-2 mol, preferably 2 × 10 ^-6 to 10 ^-3 mol, particularly preferably from 5 × 10 ^- A range of ⁶ to 10 ^-4 can be used.

If the amount exceeds the above range, a colored or branched component is likely to be formed, and if the amount is less than the above range, the effect of the catalyst is low, a sufficient reaction rate cannot be obtained, and the physical properties are liable to be deteriorated.

In the present invention, the method of charging the catalyst may be solid or liquid, but is preferably solution or suspension. The concentration of the solution or suspension may be such that it can be handled in a liquid state, and is preferably 50% by weight or less, more preferably 40% by weight or less. The concentration of oxygen dissolved in the solution or suspension is preferably 100 ppm or less, more preferably 50 ppm or less, still more preferably 10 ppm or less. If it exceeds this range, coloring or branched components are likely to be generated due to the influence of dissolved oxygen.

In the present invention, it is also preferable to add various stabilizers in a molten state at least once before the start of polymerization, during the polymerization, and after the completion of the polymerization. Examples of the stabilizer include a sulfur-containing acidic compound and / or a derivative formed from the acidic compound, a phenolic stabilizer, a thioether stabilizer, a phosphorus stabilizer, a hindered amine stabilizer, an epoxy compound, and a salicylic acid ultraviolet ray. Examples thereof include absorbers and benzotriazole-based ultraviolet absorbers.

Examples of the sulfur-containing acidic compound and / or the derivative formed from the acidic compound include sulfurous acid, sulfuric acid, sulfinic acid compounds, sulfonic acid compounds and derivatives thereof. Specifically, as the sulfuric acid derivative, dimethyl sulfuric acid, diethyl sulfuric acid, sulfuric acid,
Dipropylsulfate, dibutylsulfate, diphenylsulfate, dimethylsulfite, diethylsulfite, diphenylsulfite, sodium dodecylsulfate, sodium hexadecylsulfate, butylsulfate dimethylbutyltridecylammonium, ethylsulfate dimethylethylhexadecylammonium, methylsulfate trimethylhexadecylammonium, etc. Can be mentioned.

Examples of the sulfinic acid compound include benzenesulfinic acid, toluenesulfinic acid, naphthalene sulphinic acid and the like. Examples of the sulfonic acid compounds and their derivatives include the following compounds. That is, benzenesulfonic acid, p
-Sulfonic acids such as toluene sulfonic acid, methyl benzene sulfonate, ethyl benzene sulfonate, butyl benzene sulfonate, octyl benzene sulfonate, phenyl benzene sulfonate, methyl p-toluene sulfonate, ethyl p-toluene sulfonate, p- Butyl toluene sulfonate, p-octyl toluene sulfonate, p-
Examples thereof include sulfonates such as phenyl toluenesulfonate, ammonium p-toluenesulfonate, tetrabutylphosphonium p-toluenesulfonate, and ammonium sulfonates such as tetraphenylphosphonium dodecylbenzenesulfonate.

These compounds can be used alone or in combination. Of these, [B] pK
As a sulfur-containing acidic compound having an a value of 3 or less and a derivative formed from the acidic compound, a sulfonic acid compound and its derivative are preferably used. Particularly, benzenesulfonic acid, butylbenzenesulfonate, p-toluenesulfonic acid, Ethyl p-toluenesulfonate, butyl p-toluenesulfonate, sodium dodecyl sulfate, trimethylhexadecylammonium methyl sulfate, tetrabutylphosphonium p-toluenesulfonate, and tetraphenylphosphonium dodecylbenzenesulfonate are preferably used.

As the phenolic stabilizer, for example, n
-Octadecyl-3- (4-hydroxy-3 ', 5'-
Di-t-butylphenyl) propionate, tetrakis [methylene-3- (3 ', 5'-di-t-butyl-4-
Hydroxyphenyl) propionate] methane, 1,
1,3-Tris (2-methyl-4-hydroxy-5-t
-Butylphenyl) butane, distearyl (4-hydroxy-3-methyl-5-t-butyl) benzyl malonate, 4-hydroxymethyl-2,6-di-t-butylphenol, etc. You may use, or may mix and use 2 or more types.

Examples of the thioether stabilizer include, for example,
Dilauryl thiodipropionate, distearyl thiodipropionate, dimyristyl-3,3'-thiodipropionate, ditridecyl-3,3'-thiodipropionate, pentaerythritol-tetrakis- (β
-Lauryl-thiopropionate) and the like, and these may be used alone or in combination of two or more kinds.

Examples of phosphorus-based stabilizers include bis (2,4-di-t-butylphenyl) pentaerythrityl diphosphite, diphenyldecyl phosphite,
Arylalkyl phosphites such as phenylisooctyl phosphite, 2-ethylhexyl diphenyl phosphite; trimethyl phosphite, triethyl phosphite, tributyl phosphite, trioctadecyl phosphite, distearyl pentaerythrityl diphosphite, tris (2-chloroethyl ) Trialkylphosphites such as phosphite and tris (2,3-dichloropropyl) phosphite; tricycloalkylphosphites such as tricyclohexylphosphite; triphenylphosphite, tricresylphosphite, tris (ethylphenyl) Phosphite, Tris (2,4-di-t
-Triaryl phosphite such as -butylphenyl) phosphite and tris (hydroxyphenyl) phosphite; trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctadecyl phosphate, distearyl pentaerythrityl phosphate, tris (2-chloroethyl) phosphate, etc. Trialkyl phosphates; tricycloalkyl phosphates such as tricyclohexyl phosphate; triphenyl phosphates, tricresyl phosphates, tris (nonylphenyl) phosphates, triaryl phosphates such as 2-ethylphenyldiphenyl phosphates, and the like. You may use, or may mix and use 2 or more types.

As the hindered amine stabilizer,
For example, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, 8-benzyl-7,7,9,9
-Tetramethyl-3-octyl-1,2,3-triazaspiro [4,5] undecane-2,4-dione, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) 1,2,3 , 4-butanetetracarboxylate and the like, and these may be used alone or in combination of two or more kinds.

In the present invention, an epoxy compound can be used as the stabilizer. As such an epoxy compound, a compound having one or more epoxy groups in one molecule is used.

Specific examples of such an epoxy compound include epoxidized soybean oil, epoxidized linseed oil, phenylglycidyl ether, t-butylphenylglycidyl ether and 3,4-epoxycyclohexylmethyl-
3 ', 4'-epoxycyclohexylcarboxylate, 3,4-epoxycyclohexylethylene oxide, cyclohexylmethyl-3,4-epoxycyclohexylcarboxylate, 3,4-epoxy-6-methylcyclohexylmethyl-6'-methylsiloxyhexylcarboxylate Rate, bisphenol-A diglycidyl ether, phthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ether, bis-epoxydicyclopentadienyl ether, bis-epoxyethylene glycol, bis-epoxycyclohexyl adipate, butadiene diepoxide , Tetraphenylethylene epoxide, octyl epoxytalate, epoxidized polybutadiene, 3,4-dimethyl-1,2-epoxycyclohexane, 3,5- Methyl-1,2-epoxycyclohexane, 3-methyl -5-t-butyl-1,2
Epoxycyclohexane, octadecyl-2,2-dimethyl-3,4-epoxycyclohexylcarboxylate, N-butyl-2,2-dimethyl-3,4-epoxycyclohexylcarboxylate, cyclohexyl-2
-Methyl-3,4-epoxycyclohexylcarboxylate, N-butyl-2,2-dimethyl-3,4-epoxy-5-methylcyclohexylcarboxylate, octadecyl-3,4-epoxycyclohexylcarboxylate, 2-ethylhexyl- 3 ', 4'-epoxycyclohexylcarboxylate, 4,6-dimethyl-
2,3-Epoxycyclohexyl-3 ', 4'-epoxycyclohexylcarboxylate, 4,5-epoxy tetrahydrophthalic anhydride, 3-t-butyl-4,5-
Epoxy tetrahydrophthalic anhydride, diethyl-4,5
-Epoxy-cis-1,2-cyclohexyl dicarboxylate, di-n-butyl-3-t-butyl-4,5-
Examples thereof include epoxy-cis-1,2-cyclohexyl dicarboxylate.

Specific examples of the salicylic acid type ultraviolet absorber include phenyl salicylate and pt-butylphenyl salicylate. Examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone,
2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-methoxy-2'-
Carboxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone trihydrate, 2-
Hydroxy-4-n-octoxybenzophenone, 2,
2 ', 4,4'-tetrahydroxybenzophenone, 4
-Dodecyloxy-2-hydroxybenzophenone, bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid and the like can be mentioned.

As the benzotriazole type ultraviolet absorber, 2- (2'-hydroxy-5'-methylphenyl) is used.
Benzotriazole, 2- (2'-hydroxy-3 ',
5'-di-t-butylphenyl) benzotriazole,
2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2-
(2'-Hydroxy-3 ', 5'-di-t-butyl-phenyl) -5-chlorobenzotriazole, 2- (2'
-Hydroxy-5'-octylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-diamylphenyl) benzotriazole, 2- [2'-hydroxy-3'-(3 ", 4" , 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl] benzotriazole, 2,2'-methylenebis [4- (1,
1,3,3-Tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol] and the like.

Examples of the cyanoacrylate type ultraviolet absorber include 2-ethylhexyl-2-cyano-3,3-diphenyl acrylate and ethyl-2-cyano-3,3-diphenyl acrylate.

These compounds have 10 to 40, preferably 15 carbon atoms in the reaction system as an endcapping agent when melt-polycondensing the above aromatic compound dihydroxy compound and diaryl carbonate to produce a polycarbonate.
~ 40 phenols, based on the aromatic organic dihydroxyl compound, 0.05 to 10 mol%, preferably 0.5 to 7
It is present in an amount of mol%, more preferably 1 to 5 mol%.

The following compounds are used as the above-described phenols having 10 to 40 carbon atoms. o-
m-butylphenol, p-cyclohexylphenol, o-phenylphenol, m-isobutylphenol, mn-nonylphenol, pt-butylphenol, om-pentylphenol, p-cumylphenol, pm-pentylphenol , O-naphthylphenol, pn-pentylphenol, mn-hexylphenol, 2,6-di-t-butylphenol,
2,4-di-t-butylphenol, 3,5-di-t-
Butylphenol, 2,6-dicumylphenol, 3,
5-dicumylphenol, 2,2,2-trimethyl-4
A monohydric phenol such as a monohydroxychroman derivative such as-(hydroxyphenyl) chroman is used.

As described above, the catalysts combined in the above-mentioned use amounts are preferable because they allow the polycondensation reaction to proceed at a sufficient rate to produce a high molecular weight polycarbonate with high polymerization activity.

In the presence of such a catalyst, the polycondensation reaction between the aromatic dihydroxy compound and the carbonic acid diester can be carried out under the same conditions as the conventionally known polycondensation reaction conditions.

Specifically, the first step reaction is carried out at 80 to 25
At a temperature of 0 ° C., preferably 100 to 230 ° C., more preferably 120 to 190 ° C., under reduced pressure for about 0.5 to 5 hours, preferably 0.5 to 4 hours, more preferably 0.5 to 3 hours. Reacting an aromatic dihydroxy compound with a diaryl carbonate. Next, the reaction temperature is raised while raising the vacuum degree of the reaction system to carry out the reaction between the aromatic dihydroxy compound and the carbonic acid diester, and finally 5 mmH.
240 g or less, preferably 1 mmHg or less under reduced pressure.
A polycondensation reaction of an aromatic dihydroxy compound and a carbonic acid diester is carried out at ˜320 ° C.

The polycondensation reaction as described above may be carried out continuously or batchwise. The reactor used for carrying out the above reaction may be of a tank type, a tube type or a column type.

The polycarbonate, which is the reaction product obtained as described above, usually has an intrinsic viscosity measured at 20 ° C. (measured with an Ubbelohte viscometer at 20 ° C. in methylene chloride) of 0.1 to 1.0. It is preferably 0.2 to 0.8.

In the present invention, the polycarbonate obtained as described above is used in the usual heat stability, ultraviolet absorber, release agent, colorant, antistatic agent, lubricant, antifogging agent within the range not impairing the object of the present invention. Natural oils, synthetic oils, waxes, organic fillers, inorganic fillers and the like may be added.

[0051]

EFFECT OF THE INVENTION According to the present invention, it is possible to produce a polycarbonate having a good polymer color tone, suppressing side reactions, and producing little insoluble matter or foreign matter due to a branching reaction even when highly polymerized. Further, a branching reaction and other side reactions are suppressed even during the molding process, and it is possible to produce a polycarbonate which is less likely to be burnt in an apparatus, colored, insolubilized, produced a foreign substance, and reduced in the molecular weight.

Further, according to the method of the present invention, the high quality polycarbonate as described above can be efficiently produced with high productivity. Further, according to the method of the present invention,
The method of the present invention is extremely advantageous as a method for industrially producing a polycarbonate because the high-quality polycarbonate as described above can be continuously produced even if the polymerization apparatus is repeatedly used without washing for a long time. .

[0053]

EXAMPLES The present invention will be described below with reference to examples. In the present invention, physical properties were measured according to the following methods. (I) Intrinsic viscosity [η]: Measured in methylene chloride at 20 ° C. with an Ubbellote viscometer. (Ii) Filterability: The polymer obtained by treating the polymer in a SUS316 test tube under a nitrogen stream at 290 ° C. for 20 hours was pulverized. Polymer 5g to methylene chloride 100ml
It was added to the inside and irradiated with ultrasonic waves to dissolve. The obtained polymer solution is 0.5 kg / cm with a 1 micron Millipore filter.
The sample was filtered under pressure of ² and evaluated in the following 3 stages. "Good" ... could be filtered in less than 15 minutes. "Slightly bad" ... It could be filtered in 15 to 30 minutes. "Poor" ... The filtration time exceeds 30 minutes. (Iii) Polymer color tone (L value / b value): A cylinder temperature of 300 ° C. and injection pressure of 100 kg for a 3 mm thick injection molded plate.
/ Cm ² Mold at a mold temperature of 90 ° C., and X, Y, and Z values were determined by Nippon Denshoku Industries Co., Ltd.
The L value and the b value were measured by a transmission method with a Rence Meter ND-1001DP. (Iv) Gel evaluation: 10 g of the polymer was placed in a stainless steel container, heat-treated under the condition of 290 ° C./0.3 to 0.5 mmHg / 20 hours, and then dissolved in 500 to 1000 ml of methylene chloride to collect insoluble matter. The dry weight of the insoluble matter is expressed in% by weight with respect to the weight of the sample before dissolution. (V) Polymerization activity: The polymerization time (hour) at which the intrinsic viscosity [η] reached 0.45 was measured.

Examples 1 to 6 Bisphenol A (BP
A) 228 parts, diphenyl carbonate 225 parts, and catalysts of the types and amounts shown in Tables 1 and 2 were charged into a reaction tank (capacity 100 liters) equipped with a stirrer, a distiller and a decompressor, and the atmosphere was replaced with nitrogen. It was dissolved in. After stirring for 30 minutes, the internal temperature was raised to 180 ° C and the pressure was gradually reduced to 100
The resulting phenol was distilled off by reacting at mmHg for 30 minutes. While further raising the temperature to 200 ° C, gradually reduce the pressure to 50 m
The transesterification reaction was carried out by reacting while distilling phenol at mHg for 30 minutes.

Then, the reaction solution is transferred to the second reaction tank and 2
Gradually raise the temperature to 20 ° C and 30 mmHg, and then reduce the pressure, 30 minutes at the same temperature and pressure, and 10 mmHg and 260 ° C at 240 ° C
Then, the temperature was raised and the pressure was reduced to 1 mmHg at 270 ° C. and 1 mmHg or less at 270 ° C. and the reaction was continued.

Next, while measuring the stirring power at 270 ° C. and 1 mmHg, sampling is appropriately performed to carry out polymerization [η] =
A polymerization time of 0.45 was obtained, and finally [η] = 0.
Polycondensation was carried out with the goal of 5 to produce a polycarbonate resin. The results of measuring the physical properties of the obtained polymer are shown in Table 1
It is shown in FIG.

[0057]

[Table 1]

[0058]

[Table 2]

According to the present invention, the polycarbonate produced has a high polymerization rate and produces little insoluble foreign matter and can be rapidly filtered. In addition, gel formation is low and continuous productivity is extremely high.

[Comparative Examples 1 to 3] The reaction was carried out in the same manner as in Example 1 except that the catalysts shown in Table 3 were used, and Table 3 shows the physical properties of the obtained polymers.

[0061]

[Table 3]

According to Comparative Example 1, the reaction rate at high temperature was extremely low and a polymer having a high degree of polymerization could not be obtained. According to Comparative Example 2, the reaction rate was slow and the productivity was extremely low. According to Comparative Example 3, although the reaction rate was relatively improved, the gel formation rate was high and the continuous productivity was low.

Claims (1)

[Claims] 1. A process for producing an aromatic polycarbonate, which comprises subjecting an aromatic dihydroxy compound and a carbonic acid diester to melt polycondensation in the presence of a quaternary ammonium hydroxide compound represented by the following general formula (I). Method. Embedded image