KR0152646B1 - Process for preparing thermally stable polycarbonate - Google Patents

Abstract

The present invention uses a compound selected from the group consisting of an electron donating amine and a salt thereof as a catalyst, and heat-stable polycarbohydrates by melt-polycondensation of a diester carbonate and a dihydric phenol, characterized in that an acidic substance is used. Provided are methods for making the nates.

Description

Thermally stable polycarbonate manufacturing method

Although low pigmented high molecular weight polycarbonates are all general purpose industrial thermoplastics that are useful as plates or injection moldings, in place of glazing, the process for producing them according to the prior art has several problems. . The interfacial polycondensation process is generally effective for the production of polycarbonates, but requires the use of toxic phosgene and has the disadvantage that the polycarbonates formed are contaminated with residual chloride ions. In order to overcome these problems, Japanese Laid-Open Patent Publication No. 182336 (1988) uses a dimer phosgene, liquid trichloromethyl chloroformate, instead of toxic phosgene, and a polycar consisting of polycondensation with a special dihydric phenol by an interfacial process. The preparation of the carbonate is disclosed. However, this patent specification provides no information regarding special dihydric phenols other than 9,9-bis (4-hydroxyphenyl) -fluorene. See also Angew Chem. 99, 922 (1987) disclose the preparation of polycarbonates from 2,2-bis (4-hydroxyphenyl) propane by using triphosgene instead of toxic phosgene, although The reaction mechanism that occurs is also described.

Also, Japanese Unexamined Patent Publication No. 100824 (1992) proposes to use diaryl carbonate having a xanthone content of 10 ppm or less. Although the use of such carbonates provides relatively brightly colored polycarbonates, there is a problem that the polycarbonates obtained are somewhat yellowish compared to the polycarbonates produced by the phosgene process. .

Also, for example, US Pat. No. 4,590,257, issued May 20, 1986 to General Electric, proposes a process for preparing polycarbonate using a catalyst consisting of a combination of a nitrogen-containing basic compound and a boron compound. This method can provide relatively brightly colored polycarbonates in spite of the poor catalytic activity during the polymerization reaction, but due to the low catalytic activity during the polymerization reaction, it takes a long time for the polymerization to take place and thus low industrial productivity. There is a problem in that a side reaction occurs easily during the polymerization reaction, not only the branching structure is formed, but also the polycarbonate obtained has poor thermal stability.

The present invention relates to a process for producing low colored high molecular weight polycarbonates comprising melt-polycondensing carbonic acid diesters containing reduced amounts of certain impurities via a transesterification reaction.

In particular, the present invention relates to divalent carbonate diesters containing reduced amounts of certain impurities through transesterification in the presence of (a) basic nitrogen compounds and / or (b) alkali metal compounds and / or alkaline earth metal compounds as catalysts. A method for producing low colored high molecular weight polycarbonates including melt-polycondensation with phenols. The present invention also relates to a process for preparing thermally stable polycarbonates. In particular, the present invention provides a reduced amount through transesterification in the presence of borate as acidic catalyst and acidic material capable of neutralizing the catalyst, or in the presence of electron-donating amines and salts thereof as acidic catalyst and acidic material capable of neutralizing the catalyst. A method of producing thermally stable polycarbonates by melt-polycondensing a carbonic acid diester containing a specific impurity of divalent phenol.

The present inventors have studied extensively to solve the above problems, and do not use toxic phosgene and are reduced in the presence of (a) basic nitrogen compounds and / or (b) alkali metal compounds and / or alkaline earth metal compounds as catalyst (s). It has been found that high molecular weight polycarbonates with low coloration can be produced by melt-polycondensation of carbonic acid diesters containing a specified amount of specific impurities through transesterification with dihydric phenols.

Accordingly, a first aspect of the present invention is directed to a process for preparing polycarbonates by melt-condensing dihydric phenols and carbonic acid diesters, which substantially comprises (A) phenyl salicylate, o-phenoxybenzoic acid. And carbonic acid diesters without phenyl o-phenoxybenzoate, (B) tin ions, i.e. tin components, (C) methylphenylcarbonate or (D) phenyl salicylate and o-phenoxybenzoic acid. have.

In the present invention, the term polycarbonate means polycarbonate homopolymer, polycarbonate copolymer and polyester carbonate.

Carbonic acid diesters substantially free of (A) phenyl salicylate, o-phenoxybenzoic acid and phenyl o-phenoxybenzoate result in the sum of phenyl salicylate, o-phenoxybenzoic acid and phenyl o-phenoxybenzoate. It contains 50 ppm or less. Substantially (B) tin carbonate diester carbonate contains 5 ppm or less of tin ions. Carbonic acid diesters substantially free of (C) methylphenyl carbonate contain up to 50 ppm of methylphenyl carbonate. The carbonic acid diester substantially free of (D) phenyl salicylate and o-phenoxybenzoic acid contains 50 ppm or less of the sum total of phenyl salicylate and o-phenoxybenzoic acid. Preferred carbonic acid diesters in the first embodiment of the present invention also have a total water content of 0.3 wt% or less, hydrolyzable chlorine content of 3 ppm or less, sodium ion content, i.e., sodium content of 1 ppm or less, iron ion content that can be obtained by hydrolysis. That is, it has iron content of 1 ppm or less, copper ion content, that is, copper component content of 1 ppm or less, and phosphorus ion content, that is, phosphorus content of 20 ppm or less.

The catalyst used in the method is not particularly limited, but it is preferable to use a catalyst selected from (a) basic nitrogen compounds and / or (b) an alkali metal compound and an alkaline earth metal compound.

In addition, the present inventors have found a method for producing a polycarbonate having substantially no chloride ion and excellent thermal stability without using toxic phosgene after extensive research. The present invention has been completed based on this finding.

Accordingly, a second embodiment of the present invention provides a method for producing thermally stable polycarbonate by melt-polycondensing dihydric phenol and carbonic acid diester, which method is selected from the group consisting of borate as catalyst. The use of compounds selected from the group consisting of compounds or electron donating amines and salts thereof, and optionally using acidic materials capable of neutralizing these catalysts, ie basic catalysts.

In the process it is advantageous to use monomers as carbonic acid diesters containing reduced amounts of certain impurities.

In this reaction, carbonic acid diesters, esters or phenolic compounds can be added to the reaction system as end-blockers. The blocking agent is preferably used in an amount of 0.05 to 10 mol%, more preferably in an amount of 1 to 5 mol%, based on the dihydric phenol.

Further scope and applicability of the present invention will become apparent from the detailed description set forth below. It is to be understood, however, that the description and the specific examples are merely illustrative of the preferred embodiments of the invention and are provided for illustration only, and various modifications and changes within the spirit and scope of the invention will be described in detail from the description of the invention. It will be apparent to those skilled in the art.

Representative examples of carbonic acid diesters used in the present invention include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (Biphenyl) carbonate, diethyl carbonate, dimethyl carbonate, dibutyl carbonate and dicyclohexyl carbonate, and the like, of which diphenyl carbonate is particularly preferred.

In the present invention, one or more carbonic acid diester (s) is used as the monomer (s). Alternatively, a combination of carbonic acid diesters and dicarboxylic acid esters may be used in the present invention. Examples of dicarboxylic acid esters are diphenyl telephthalate and diphenyl isophthalate. In this case, the amount of dicarboxylic acid ester is 50 mol% or less based on the total amount of the carbonic acid diester and the dicarboxylic acid ester, and the polyester carbonate is obtained by melt-condensation. In other words, in the present invention, the term carbonic acid diester generally includes dicarboxylic acid esters as well. When using two or more carbonic acid diesters, a copolymer is obtained.

In a first embodiment of the present invention, substantially (A) phenyl salicylate, o-phenoxybenzoic acid and phenyl o-phenoxybenzoate, (B) tin ions, (C) methylphenyl carbonate or (D) Carbonic diesters without phenyl salicylate and o-phenoxybenzoic acid are used. These impurities affect the color tone and heat resistance of the resulting polymer.

In the first embodiment of the present invention, the total moisture content of 0.3wt% or less, the chlorine content of 3ppm or less, the sodium ion content of 1ppm or less, the iron ion content of 1ppm or less, the copper ion content of 1ppm or less and the phosphorus ion content 50 ppm or less of (A) phenyl salicylate, o-phenoxybenzoic acid and phenyl o-phenoxybenzoate, (B) tin ion content of 5 ppm or less, and (C) methylphenyl carbonate content of 50 ppm It is preferable to use carbonic acid diester which has at least one of the following. Optionally less than 0.3wt% total moisture content, less than 3ppm chlorine content that can be obtained by hydrolysis, less than 1ppm sodium ion, less than 1ppm iron ion, less than 1ppm copper ion, less than 20ppm phosphorus ion and (D) phenyl Preference is also given to using carbonic acid diesters having a total content of salicylate and o-phenoxybenzoic acid of up to 50 ppm. When using carbonic acid diesters which do not meet the above requirements other than the total moisture content, the resulting polycarbonates may have significant coloring and poor physical properties, in particular poor thermal stability. If the carbonic acid diester has a moisture content of more than 0.3 wt%, the diester is hydrolyzed during the reaction to lose the molar balance of the monomers, resulting in the formation of a polymer having a high degree of polymerization.

In the present invention, chlorine contributing to the chlorine content includes free chlorine ions, chlorine present in the form of a salt, chlorine present in the form of an organic chlorine compound that can be separated by hydrolysis. Chlorine is therefore present as being obtained by hydrolysis of salts such as sodium chloride or potassium chloride and organochlorine compounds such as phenyl chloroformate, which contributes to the chlorine content of the present invention. The removal of the above impurity from the carbonic acid diester is, for example, (1) a method of washing the carbonic acid diester with warm water or a slightly basic aqueous solution, (2) a method of adding urea to the carbonic acid diester and heat-melting the obtained mixture, Or (3) adding a salt of an alkali metal or alkaline earth metal, such as Na ₂ CO ₃ , NaHCO ₃ , KH ₂ PO ₄ or K ₂ HPO ₄ , to the carbonic acid diester and distilling the resulting mixture in vacuo. . Methods for specifying impurities in carbonic acid diesters are described in the Examples herein.

In the second embodiment of the present invention, there is no limitation on the carbonic acid diester used as the monomer, but it is preferable to use one having a reduced amount of impurities, such as that used in the first embodiment of the present invention. Optionally up to 3 ppm chlorine, sodium ions up to 1 ppm, iron ions up to 1 ppm, total phenyl salicylate, o-phenoxybenzoic acid and phenyl o-phenoxybenzoate up to 50 ppm and Carbonic acid diesters having a methylphenyl carbonate content of 10 ppm or less, or chlorine content of 3 ppm or less, sodium ion content of 1 ppm or less, iron ion content of 1 ppm or less, and phenyl salicylate, o-phenoxybenzoic acid and phenyl It is advantageous to use carbonic acid diesters having a total content of 50 ppm or less of o-phenoxybenzoate.

Representative examples of the dihydric phenol used in the present invention include those represented by the following Chemical Formulas 1 to 4.

Wherein R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are each a hydrogen atom, a linear or branched alkyl group having 1 to 8 carbon atoms or a phenyl group, X is a halogen atom, n is 0 or 1 to 4 Is an integer and m is an integer of 1-4.

Examples of bisphenols which are dihydric phenols represented by the formula (1) include 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxy Phenyl) -4-methylpentane, 2,2-bis (4-hydroxyphenyl) octane, 4,4'-dihydroxy-2,2,2-triphenylethane and 2,2-bis (3,5 Dibromo-4-hydroxyphenyl) propane.

Examples of the bisphenol represented by the formula (2) include 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3-isopropylphenyl) propane, 2,2-bis ( 4-hydroxy-3-sec-butylphenyl) propane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane and 2,2-bis (4-hydroxy-3-t-butyl Phenyl) propane.

Examples of the bisphenol represented by the formula (3) include 1,1'-bis (4-hydroxyphenyl) -p-diisopropylbenzene and 1,1'-bis (4-hydroxyphenyl) -m-diisopropylbenzene have.

Bisphenols represented by the formula (4) include 1,1-bis (4-hydroxyphenyl) cyclohexane. Polycarbonate copolymers may also be prepared using two or more dihydric phenols selected from those represented by Formulas 1-4.

The required amount of diester carbonate is the same molar amount as the amount of dihydric phenol present in the reaction system. In general, carbonate compounds must be reacted with dihydric phenols in a molar ratio of 1: 1 to form high molecular weight polycarbonates. When bisphenyl carbonate is used as the carbonate compound, bisphenyl carbonate and dihydric phenol react to form 2 moles of phenol. Phenol is distilled off and removed from the reaction system. In the present invention, diester carbonate is used in an amount of 1.01 to 1.5 moles per mole of dihydric phenol, in order to improve the physical properties of the polycarbonate, in particular to reduce the terminal hydroxy content such that the adverse effect on the color tone is eliminated as much as possible, Preferably an amount of 1.015 to 1.20 moles is used.

The terminal hydroxy concentration of the polycarbonate obtained according to the present invention is preferably in the range of 3 to 70 mol%, more preferably 3 to 50 mol%, even more preferably 3 to 30 mol%. It is practically difficult to obtain terminal hydroxy concentrations lower than 3 mole%. On the other hand, if it exceeds 30 mol%, the resulting polymer becomes considerably colored, and if it exceeds 50 mol%, the thermal stability of the polymer is also impaired. Polycarbonates having a terminal hydroxy concentration of 3 to 50 mole% can be used alone. Polycarbonates having a terminal hydroxy concentration of 50 to 70 mole percent can be used in the form of mixtures with other polymers. In order to lower the terminal hydroxy concentration of the resulting polymer, carbonic acid diesters, esters or phenolic compounds can be added to the reaction system as end-blockers. The blocking agent is preferably used in an amount of 0.05 to 10 mol%, more preferably 1 to 5 mol%, based on the dihydric phenol. The diesters of carbonic acid are therefore also used as monomers and as blocking agents. The amount of diester carbonate therefore affects the terminal hydroxy concentration of the resulting polymer. In a first embodiment of the present invention, the melt polycondensation of dihydric phenols and carbonic acid diesters comprises the presence of (a) basic nitrogen compounds and / or (b) alkali metal compounds and / or alkaline earth metal compounds as catalyst (s). Preferably under the presence of a basic nitrogen compound and optionally an alkali or alkaline earth metal compound.

Representative examples of basic nitrogen compounds that can be used in the present invention include tetramethylammonium hydroxide (Me ₄ NOH), tetraethylammonium hydroxide (Et ₄ NOH), tetrabutylammonium hydroxide (Bu ₄ NOH) and trimethyl Alkyl-, aryl- and alkylarylammonium hydroxides such as benzylammonium hydroxide (C ₆ H ₅ -CH ₂ (Me) ₃ NOH); Tertiary amines such as trimethylamine, triethylamine, dimethylbenzylamine and triphenylamine: secondary represented by the formula R ₂ NH, where R is an alkyl group such as methyl or ethyl group or an aryl group such as phenyl or tolyl group Amines; Primary amines represented by the formula RNH ₂ , where R is as defined above; ammonia; And tetramethyl ammonium borohydride (Me ₄ NBH ₄ ), tetrabutylammonium borohydride (Bu ₄ NBH ₄ ), tetrabutylammonium tetraphenylborate (Bu ₄ NBPh ₄ ) and tetramethylammonium tetraphenylborate (Mu ₄ NBPh ₄ ) basic salts. Examples of other basic nitrogen compounds include 4- (4-methyl-1-piperidinyl) pyridine, N, N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 4-pyrrolidinopyridine, 4-amino Pyridine, 2-amino-pyridine, 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 4-hydroxypyridine, 2-dimethylaminoimidazole, 2-methoxyimidazole, 2-mercaptoy Midazole, aminoquinoline, benzimidazole, imidazole, 2-methylimidazole, 4-methylimidazole, diazabicyclooctane (DABCO), 1,8-diazabicyclo [5.4.0] -7- Undeken (DBU) and 4- (4-methylpyrrolidinyl) pyridine. Representative examples of alkali metal compounds include sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium bicarbonate, potassium bicarbonate, lithium bicarbonate, sodium carbonate, potassium carbonate, lithium carbonate, sodium acetate, potassium acetate, lithium acetate, sodium stearate, stearic acid Potassium acid, lithium stearate, sodium borate, lithium borate, potassium borate, sodium borate, lithium borate, potassium borate, sodium borate monosodium, sodium benzoate, potassium benzoate, lithium benzoate, sodium diphosphate, dibasic potassium phosphate And sodium dibasic, dipotassium and dilithium salts of bisphenol A, sodium, potassium and lithium salts of phenol, among which lithium borate, potassium borate and potassium acetate are preferred. Representative examples of alkaline earth compounds include calcium hydroxide, barium hydroxide, magnesium hydroxide, strontium hydroxide, calcium hydrogen carbonate, barium hydrogen carbonate, magnesium hydrogen carbonate, strontium bicarbonate, calcium carbonate, barium carbonate, magnesium carbonate, strontium carbonate, barium acetate, acetic acid Magnesium, strontium acetate, calcium stearate, barium stearate, magnesium stearate and strontium stearate. The amount of the basic nitrogen compound used as the catalyst is used in the range of 10 ^-6 to 10 ^-1 mole, preferably 10 ^-4 to 10 ^-2 mole per mole of divalent phenol present in the reaction system. If the amount of the catalyst is less than 10 ^-6 moles, the catalytic activity is poor and the polymerization reaction is slowed. On the other hand, if the amount of the catalyst exceeds 10 ^-1 mole, the obtained polycarbonate is significantly contaminated with the catalyst, resulting in poor physical properties. Will fall out. The total amount of alkali metal and alkaline earth metal compound used as a catalyst is in the range of 10 ⁻⁷ to 10 ⁻² moles, preferably 10 ⁻⁵ to 10 ⁻³ moles per mole of divalent phenol present in the reaction system. If this amount is less than 10 ^-7 moles, the catalytic activity is so bad that a polycarbonate having the desired degree of polymerization cannot be obtained, whereas if it exceeds 10 ^-2 moles, the resulting polycarbonate is significantly contaminated with co-catalyst. This results in poor physical properties.

In a second embodiment of the present invention, a compound selected from the group consisting of borate salts or a compound selected from the group consisting of electron donating amines and salts thereof is used as a catalyst. In the second embodiment of the present invention, an acidic substance capable of neutralizing the catalyst can also be usefully used. Representative examples of borate salts that can be used in the present invention as a transesterification catalyst include sodium diborate, sodium tetraborate, sodium pentaborate, sodium hexaborate, sodium octaborate, lithium metaborate, lithium tetraborate, lithium pentaborate, metaborate Potassium, potassium tetraborate, potassium pentaborate, potassium hexaborate potassium octaborate, ammonium metaborate, ammonium tetraborate, ammonium pentaborate, ammonium octaborate, ammonium borate, tetramethylammonium borate, potassium borate, calcium borate, silver borate Copper borate, lead borate, nickel borate, magnesium borate, and manganese borate, among which alkali metal salts of boric acid are preferred. These borate salts may be used alone or in combination of two or more borate salts. When two or more borate salts are used in combination, they may be added simultaneously with the supply of monomers or may be added stepwise as the reaction progresses. When one borate is used, it can be fed to the reactor with the supply of monomer or can be fed in stages as the reaction progresses. The total amount of one or more circle (s) selected from the group consisting of borate salts used as a catalyst is preferably 10 ^-6 to 10 ^-1 mole, more preferably 10 ^-4 per mole of divalent phenol present in the reaction system. To 10 ^-2 moles. If the amount is less than 10 ^-6 mole, the catalytic activity is low and the polymerization is too slow, while if the amount is more than 10 ^-1 mole, the resulting polycarbonate is significantly contaminated with borate (s). This results in poor physical properties.

Examples of electron donating amines used in the present invention include 4- (4-methyl-1-piperidinyl) pyridine, N, N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 4-pyrrolidino Pyridine, 4-aminopyridine, 2-aminopyridine, 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 4-hydroxypyridine, 2-dimethylaminoimidazole, 2-methoxyimidazole, 2-mercaptoimidazole, aminoquinoline, benzimidazole, imidazole, 2-methylimidazole, 4-methylimidazole, diazabicyclooctane (DABCO), 1,8-diazabicyclo [5.4.0 ] -7-undecene (DBU) and 4- (4-methylpyrrolidinyl) pyridine. Representative examples of acids that also act as counterions of electron donating amines, that is, constituting part of the salts of electron donating amines, include carbonic acid, acetic acid, formic acid, nitric acid, nitrous acid, oxalic acid, sulfuric acid, phosphoric acid, boric acid and boric acid There is this. These electron-donating amines and salts thereof may be used alone, or two or more thereof may be used in combination. When two or more are used in combination, they may be added simultaneously with the supply of monomers, or may be added stepwise depending on the course of the reaction. When only one compound is used, it can be fed to the reactor with the supply of monomer or can be fed in stages as the reaction progresses. The total amount of at least one source (s) selected from the group consisting of electron donating amines and salts thereof used as a catalyst is preferably 10 ^-6 to 10 ^-1 mole per mole of divalent phenol present in the reaction system, more preferably Preferably from 10 ^-4 to 10 ^-2 moles. If the amount is less than 10 ^-6 mole, the catalytic activity is low and the polymerization is too slow, whereas if the amount is more than 10 ^-1 mole, the resultant polycarbonate is the electron-donating amine and / or their Significant contamination with salts results in poor physical properties.

In the present invention, acidic materials used to neutralize the salts of the basic materials used as catalysts, such as borates, electron donating amines or electron donating amines, include boric acid and ammonium hydrogenphosphite, which can be used alone or as a mixture. have.

When borate is used as a catalyst, the acidic substance contributing to the thermal stability of the resulting polycarbonate is preferably used in a molar amount of 1 to 500 times the molar amount of the catalyst used, and 1 to 1 mole of the catalyst amount used. It is more preferable to use 20 times the molar amount. Use of a molar amount less than the molar amount of the catalyst does not provide the effect of imparting thermal stability, while using a molar amount of more than 500 times the molar amount of the catalyst used results in a low degree of polymerization in which the resulting polycarbonate is undesirable. Will have When using electron donating amines and / or salts thereof as catalyst (s), the acidic materials contributing to the thermal stability of the resulting polycarbonate use a molar amount of 0.01 to 500 times the molar amount of catalyst used. It is preferable to use, and it is more preferable to use a molar amount of 1 to 20 times or 0.01 to 0.5 times the molar amount of the catalyst used. Using a molar amount less than 0.01 times the molar amount of catalyst used will not give the effect of imparting thermal stability, whereas using a molar amount greater than 500 times the molar amount of catalyst used will result in undesirable polycarbonates formed. It has a low degree of polymerization.

The acidic substance may be added simultaneously with the raw monomers (ie divalent phenol and carbonic acid diester) and the transesterification catalyst, or the relative viscosity of the formed polymer (chlorinated with a polymer content of 0.5 g / dl at 20 ° C). May be added at any point in time as measured using a methylene solution). Optionally, the acidic material may be added to the reaction product after completion of the reaction, ie, the polycarbonate, to provide a polycarbonate composition. In the process according to the first and second embodiments of the present invention, the melt-polycondensation reaction can be carried out in a temperature range of 100 ° C to about 300 ° C. 130-280 degreeC of reaction temperature is preferable. If the reaction temperature is lower than 100 ° C, the reaction is too slow, and if it exceeds 300 ° C, side reactions are likely to occur.

In a second embodiment of the present invention, the thermal stability of the resulting polycarbonate can be further improved using phosphorus compounds and / or hinderphenols.

Representative examples of phosphorus compounds that can be used in the present invention include triethyl phosphite, triisopropyl phosphite, triisodecyl phosphite, tridodecyl phosphite, phenyldiisodecyl phosphite, diphenylisodecyl phosphite, tri Phenyl phosphite, tristolyl phosphite, phenylbis (4-nonylphenyl) phosphite, tris (4-octylphenyl) phosphite, tris (4- (1-phenylethyl) phenyl) phosphite, tris (2, 4-di-t-butylphenyl) phosphite, tetrakis (2,4-di-t-butylphenyl) 4,4'-biphenylenediphosphonite represented by the following formula:

Pentaerythritol di [(2,6-di-t-butyl-4-methylphenyl) phosphite] represented by the following formula:

Pentaerythritol di [(2,4-di-t-butylphenyl) phosphite] represented by the following formula:

Tetrakis (2,4-di-t-butylphenyl) 4,4 '-(2,2-diphenylpropane) phosphonite represented by the following formula:

And dialkylphenylphosphor represented by the following formula

(Wherein R ₆ and R ₇ each represent a linear or branched alkyl group having 1 to 20 carbon atoms, and Ph represents a phenyl group).

The said phosphorus compound can be used in combination of 2 or more. The phosphorus compound may be added simultaneously with the supply of the raw monomer or may be added at any time after the start of the reaction. Alternatively, the phosphorus compound may be added to the reaction product after completion of the reaction to provide a polycarbonate composition. The amount of the phosphorus compound used is preferably 10 to 1000 ppm based on the dihydric phenol. Adding an amount less than 10 ppm is ineffective in improving the thermal stability of the resultant polymer, whereas adding an amount exceeding 1000 ppm has an undesirable side effect on the physical properties of the resulting polymer. Representative examples of hinderphenols that may be used in the present invention include octadecyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, N, N'-hexamethylenebis (3,5-di -t-butyl-4-hydroxyhydrocinnaamide), triethylene glycol bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol bis [ 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], pentaerythritol tetrakis [3- (3,5-di-t-butyl-4- hydroxyphenyl) propionate ], Diethyl 3,5-di-t-butyl-4-hydroxybenzylphosphonate, and a compound represented by the following formulas (10) to (12).

The hinder phenol can be used in combination of two or more.

The hinderphenol may be added simultaneously with the supply of the raw monomer or may be added at any time after the start of the reaction. Optionally, the hinderphenol may be added to the reaction product after completion of the reaction to provide a polycarbonate composition. The hinderphenol and phosphorus compound may be added simultaneously or at any different time.

The hinderphenol is preferably added in an amount of 10 to 2000 ppm based on the dihydric phenol. If the amount is less than 10ppm it will be ineffective in improving the thermal stability of the resulting polymer, while addition of more than 2000ppm has an undesirable side effect on the physical properties of the resulting polymer.

Example

The present invention will be described in more detail with reference to the following examples. However, this embodiment should not be construed as limiting the scope of the present invention.

Various numerical values shown in the following examples were measured as follows.

(1) Viscosity-average molecular weight (Mv)

Viscosity-average molecular weight (Mv) was measured at 20 ° C. using a Ubbellohde viscometer according to the following formula and was calculated based on the intrinsic viscosity [η] of the methylene chloride solution of each polycarbonate.

(2) terminal hydroxy concentration

Terminal hydroxy concentration was measured by applying each polycarbonate to a ¹³ C-NMR spectrometer according to the gated decoupling measurement mode and calculating the area ratio of the peak at 114.80 ppm to the peak at 129.50 ppm.

(3) impurity content

a) Method for measuring the content of phenyl salicylate, o-phenoxybenzoic acid, phenyl o-phenoxybenzoate or methylphenyl carbonate.

The content was measured using gas chromatography (Shimadzu, GC-14A).

b) chlorine content measurement method.

(Comparative) Examples I-1 to I-11 and IV-1 to IV-7

Sample (5 g) was dissolved in 10 ml of toluene, and 10 ml of eluent (aqueous solution containing 2.8 mmol NaHCO ₃ and 2.25 mmol Na ₂ CO ₃ ) and 15 mL high deionized water were added in this order. The resulting mixture was stirred and placed in a stand. The upper layer of toluene was removed. The resulting aqueous layer was treated with C-18 SEPPAK to be free of toluene contaminants. The resulting water-soluble layer was subjected to ion chromatography (YOKOGAWA SAX-1) to measure the chlorine content.

(Comparative) Examples II-1 to II-16 and III-1 to III-28

Chlorine content was measured using ion chromatography (YOKOGAWA ELECTRIC WORKS IC 100).

c) Method of measuring sodium or iron ion content

The content was measured using an atomic absorption spectrometer (SAS-727, manufactured by Seiko Instruments).

d) measuring copper or phosphorus ions content

The content was measured using an inductively coupled plasma (ICP) emission spectrometer (Shimadzu, ICPS-1000III).

e) method of measuring tin ion content

The content was measured using an atomic absorption spectrometer (Shimadzu, AA-670 G) and a graphite furnace analyzer (Shimadzu, GFA-4A).

f) how to determine the moisture content

The content was measured using a trace water measuring device (Mitsubishi Chemical Industries Ltd., CA-05).

(4) storage stability

a) tint

The color tone (YI) of each polycarbonate, polyester carbonate or polycarbonate composition was produced by thermal pressure quenching before and after storage at 160 ° C. for 720 hours (50 × 50 × 2 mm (HWD)]. Was measured on a colorimeter (Nippon Denshoku, 300A).

b) Number of cleavage

Using a pressure quenching process with a polycarbonate, polyester carbonate or polycarbonate composition prepared by one of the (comparative) examples of Examples II-1 to II-16 and III-1 to III-28 To produce a sheet having a thickness of 0.5 mm (50 mm x 50 mm). The obtained sheet was stored at 160 ° C. and the viscosity-average molecular weight of the polycarbonate or polyester carbonate constituting the sheet was measured after 10, 20 and 30 days. The method of measuring a viscosity-average molecular weight was the same method as described in (1) Viscosity-average molecular weight (Mv). In addition, the number of cleavage of a polymer was calculated by the following formula.

Mv _o : Initial viscosity-Average molecular weight

Mv _t : viscosity after t days-average molecular weight

Example I-1

22.8 g (0.1 mol) of 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.164 g of 2-methylimidazole (2 x 10 ^-2 mol per mol of BPA), 0.00082 g of sodium acetate (BPA 1 21.96 g (0.1025 mol) of diphenylcarbonate having 1 × 10 ⁻⁴ ) per mole and impurity contents shown in Table 1 were placed in a reactor and stirred together at 180 ° C. under nitrogen atmosphere for 1 hour. The temperature of the resulting mixture was raised while venting the reaction system in stages. Finally the mixture was polycondensed at 270 ° C. under vacuum of 0.1 Torr for 1 hour while removing the phenol formed by distillation. As a result, a colorless and transparent polycarbonate was obtained. Its viscosity-average molecular weight (Mv) was 27,600. The glass transition point was 150 ° C. and the terminal hydroxy content was 28 mol%. In order to know the color degree at the time of storage, the color tone after the initial color tone and storing for 720 hours at 160 ℃ is shown in Table 2.

Example I-2

0.00122 g of 4-dimethylaminopyridine (1 × 10 ⁻⁴ mole per mole of BPA) was used in place of 2-methylimidazole and 0.00098 g of potassium carbonate (1 × 10 ⁻⁴ mole per mole of BPA) was used in place of sodium acetate , Except that another diphenyl carbonate having an impurity content shown in Table 1 was used to prepare another colorless transparent polycarbonate through the polycondensation reaction in the same manner as in Example I-1. The viscosity-average molecular weight (Mv) was 27,000. The glass transition point was 150 ° C. and the terminal hydroxy content was 25 mol%. Table 2 shows the initial color tone and the color tone after storage at 160 ° C. for 720 hours.

Example I-3

11.4 g of 2,2-bis (4-hydroxyphenyl) propane (50 mol% of dihydric phenol used), 17.0 g of 2,2-bis (4-hydroxy-3-t-butylphenyl) propane (use 50 mole% of divalent phenol), 0.00122 g of 4-dimethylaminopyridine (1 × 10 ⁻⁴ mole per mole of bivalent phenol), 0.000066 g of lithium acetate (1 × 10 per mole of bisphenol ^-5 mole) and 21.96 g (0.1025 mole) of diphenylcarbonate having the impurity contents shown in Table 1 were fed to the reactor and stirred together under a nitrogen atmosphere for 2 hours. The resulting mixture was polycondensed in the same manner as in Example I-1 to give a colorless transparent polycarbonate. The viscosity-average molecular weight (Mv) was 24,500 and the glass transition point was 128 ° C. Terminal hydroxy content was 23 mol%. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 2.

Example I-4

0.00091 g of tetramethylammonium hydroxide (1 × 10 ^-4 moles per mole of BPA) is used instead of 2-methylimidazole, and 0.00098 g of potassium acetate (1 × 10 ^-4 moles per mole of BPA) is used instead of sodium acetate And using the other raw diphenyl carbonate having the impurity contents shown in Table 1, except that the contents of the reactor, that is, the raw materials were stirred together in a nitrogen atmosphere for 2 hours, and In the same manner, other colorless transparent polycarbonate was prepared through polycondensation. The viscosity-average molecular weight (Mv) was 27,800. The glass transition point was 151 degreeC. Terminal hydroxy content was 21 mol%. The first color tone and color tone after storage at 160 ° C. for 720 hours are shown in Table 2.

Example I-5

22.8 g (0.1 mole) of 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.0024 g of 4-dimethylaminopyridine (2 × 10 ⁻⁴ mole per mole of BPA) and impurity contents shown in Table 1 21.96 g (0.1025 mol) of diphenyl carbonate were fed to the reactor, and the resulting mixture was polycondensed in the same manner as in Example I-1 to obtain a colorless transparent polycarbonate. The viscosity-average molecular weight (Mv) was 29,000 and the glass transition point was 150 ° C. Terminal hydroxy content was 26 mol%. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 2.

Example I-6

22.8 g (0.1 mol) of 2,2-bis (4-hydroxyphenyl) propane, 0.00122 g of 4-dimethylaminopyridine (1 × 10 ⁻⁴ mol per mol of BPA), 8.58 × 10 ⁻⁸ g of lithium borate (BPA 1 1 x ^10-6 moles per mole) and 21.96 g (0.1025 moles) of diphenyl carbonate having the impurity contents shown in Table 1 were fed to the reactor and the resulting mixture was polycondensed in the same manner as in Example I-1 to give a colorless transparent Polycarbonate was obtained. The viscosity-average molecular weight (Mv) was 31,000 and the glass transition point was 155 ° C. Terminal hydroxy content was 24 mole%. The initial color tone and color tone after storage at 160 ° C. for 720 hours are shown in Table 2.

Comparative Example I-7

22.8 g (0.1 mole) 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.0024 g N, N-dimethylaminopyridine (2 × 10 ⁻⁴ mole per mole BPA) and impurity content shown in Table 1 21.96 g (0.1025 mol) of diphenyl carbonate having was added to a reactor, and the mixture was polycondensed in the same manner as in Example I-1 to obtain a pale red polycarbonate. The viscosity-average molecular weight (Mv) was 26,500 and the glass transition point was 148 ° C. Terminal hydroxy content was 40 mol%. The initial color tone and color tone after storage at 160 ° C. for 720 hours are shown in Table 2.

Comparative Example I-8

22.8 g (0.1 mol) of 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.0024 g of N, N-dimethylaminopyridine (2 x 10 ^-4 mol per mol of BPA), 0.00098 g of potassium acetate (BPA) 1 mole (1 × 10 ⁻⁴ mole per mole) and 21.96 g (0.1025 mole) of diphenyl carbonate having the impurity contents shown in Table 1 were added to the reactor, and the mixture was polycondensed in the same manner as in Example I-1. Red polycarbonate was obtained. The viscosity-average molecular weight (Mv) was 19,500 and the glass transition point was 130 ° C. Terminal hydroxy content was 35 mol%. The initial color tone and color tone after storage at 160 ° C. for 720 hours are shown in Table 2.

Comparative Example I-9

22.8 g (0.1 mol) of 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.0024 g of N, N-dimethylaminopyridine (2 x 10 ^-4 mol per mol of BPA), 0.00098 g of potassium acetate (BPA) 1 mole of 1 × 10 ⁻⁴ mole per mole) and 21.96 g (0.1025 mole) of diphenyl carbonate having the impurity contents shown in Table 1 were added to the reactor, and the mixture was polycondensed in the same manner as in Example I-1 to give yellow color. Polycarbonate of was obtained. The viscosity-average molecular weight (Mv) was 24,500 and the glass transition point was 145 ° C. Terminal hydroxy content was 28 mol%. The initial color tone and color tone after storage at 160 ° C. for 720 hours are shown in Table 2.

Comparative Example I-10

22.8 g (0.1 mol) of 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.0024 g of N, N-dimethylaminopyridine (2 x 10 ^-4 mol per mol of BPA), 0.00098 g of potassium acetate (BPA) 1 mole (1 × 10 ⁻⁴ mole per mole) and 21.96 g (0.1025 mole) of diphenyl carbonate having the impurity contents shown in Table 1 were added to the reactor, and the mixture was polycondensed in the same manner as in Example I-1. Red polycarbonate was obtained. The viscosity-average molecular weight (Mv) was 26,000 and the glass transition point was 145 ° C. Terminal hydroxy content was 25 mol%. The initial color tone and color tone after storage at 160 ° C. for 720 hours are shown in Table 2.

Example I-11

22.8 g (0.1 mole) 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.0024 g N, N-dimethylaminopyridine (2 × 10 ⁻⁴ mole per mole BPA) and impurity content shown in Table 1 21.96 g (0.1025 mole) of diphenyl carbonate having was added to a reactor and the resulting mixture was polycondensed in the same manner as in Example I-1 to obtain a colorless transparent polycarbonate. The viscosity-average molecular weight (Mv) was 15,800 and the glass transition point was 130 ° C. Terminal hydroxy content was 10 mol%. The initial color tone and color tone after storage at 160 ° C. for 720 hours are shown in Table 2.

Example II-1

4560 g (20 mol) of 2,2-bis (4-hydroxyphenyl) propane, 4391.5 g (20.5 mol) of diphenyl carbonate having an impurity content shown in Table 3, 38 mg (1 × 10 ^-4 mol) of sodium tetraborate ) And 30.9 mg (5 × 10 ⁻⁴ mole) of boric acid were placed in a bath-like nickel-plating reactor. The contents in the reactor were melted at 160 ° C. in a nitrogen atmosphere and stirred together for 1 hour. The reaction mixture was evacuated in stages, the resulting mixture was raised to distillation and the resulting phenol was distilled off and finally polycondensed under vacuum at 1 Torr for 4 hours at 270 ° C. The resulting mixture was further reacted in a self-cleaning vertical two-screw reactor for 50 minutes to give a colorless transparent polycarbonate. The viscosity-average molecular weight (Mv) of the polycarbonate was 35,000. Terminal hydroxy content was 18 mol%. The number of cleavage after storage which shows the thermal deformation degree of polycarbonate is shown in Table 3. In addition, in order to show the degree of coloring for the storage of polycarbonate, the first color tone and the color tone after storing for 720 hours at 160 ° C. are shown in Table 3.

Example II-2

30.5 mg (1 × 10 ^-4 mol) of potassium octaborate was used in place of sodium tetraborate (38 mg, 1 × 10 ^-4 mol), except that other diphenyl carbonates having impurity contents shown in Table 3 were used. Another colorless transparent polycarbonate was prepared through the polycondensation reaction in the same manner as in Example II-1. The viscosity-average molecular weight (Mv) of obtained resin was 38,000. Terminal hydroxy content was 21 mol%. The number of cuts after storage is shown in Table 3. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 3.

Example II-3

19 mg (5 × 10 ^-5 mole) of sodium tetraborate and 15.3 mg (5 × 10 ^-4 mole) of potassium octaborate are used in place of sodium tetraborate (38 mg, 1 × 10 ^-4 mole), and 40 mg of boric acid used (6.5 X10 ^-4 mole) and other colorless transparent polycarbonate through a polycondensation reaction in the same manner as in Example II-1 except that another diphenyl carbonate having an impurity content shown in Table 3 was used. Prepared. The viscosity-average molecular weight (Mv) of obtained resin was 32,000. Terminal hydroxy content was 16 mol%. The number of cuts after storage is shown in Table 3. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 3.

Example II-4

Example II except 50 mg (5 × 10 ⁻⁴ mol) of ammonium hydrogen phosphate was used in place of boric acid (30.9 mg, 5 × 10 ⁻⁴ mol) and other diphenyl carbonates having impurity contents shown in Table 3 were used. Another colorless transparent polycarbonate was prepared through the polycondensation reaction in the same manner as -1. The viscosity-average molecular weight (Mv) of obtained resin was 29,500. Terminal hydroxy content was 23 mol%. The number of cuts after storage is shown in Table 3. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 3.

Example II-5

3648 g (16 mol) of 2,2-bis (4-hydroxyphenyl) propane, 1272 g (4 mol) of diphenyl isophthalate, 4391.5 g (20.5 mol) of diphenyl carbonate having impurity contents shown in Table 3, tetra sodium borate were added to 38mg (1 × 10 ^-4 mol) and boric acid 30.9mg (5 × 10 ^-4 mol) to the reactor as in example II-1. The contents of the reactor were melted in a nitrogen atmosphere at 180 ° C. and stirred together for 1 hour. Thereafter, the melted mixture was subjected to the polycondensation treatment in the same manner as in Example II-1 to obtain a polyester carbonate copolymer. The viscosity-average molecular weight (Mv) of the obtained resin was 29,200. Terminal hydroxy content was 18 mol%. The number of cuts after storage is shown in Table 3. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 3.

Example II-6

A diphenyl carbonate having an impurity content shown in Table 3 was used and 100 ppm of tris (2,4-di-t-butylphenyl) phosphite was added as a phosphorus compound to the raw material used in Example II-1. In the same manner as in Example II-1, another colorless transparent polycarbonate was prepared. When the polycarbonate obtained 200 ppm of octadecyl 3- (3,5-di-t-butyl-4-hydroxyphenyl propionate as a hinder phenol is in the molten state, it is added to this polycarbonate and the polycarbonate composition The polycarbonate composition was extruded into strands and cut using a gear pump The viscosity-average molecular weight (Mv) of the polycarbonate was 26,700 The terminal hydroxy content was 16 mol%. The number of cuts after storage is shown in Table 3. The initial color tone and the color tone after 720 hours storage at 160 ° C. are shown in Table 3.

Example II-7

17.2 mg (2 × 10 ^-4 mol) of lithium metaborate is used in place of sodium tetraborate (38 mg, 1 × 10 ^-4 mol), and 61.8 mg (1 × 10 ^-3 mol) of boric acid is used. Another colorless transparent polycarbonate was prepared through the polycondensation reaction in the same manner as in Example II-1 except for using another diphenyl carbonate having an impurity content as shown in Example 3. The viscosity-average molecular weight (Mv) of obtained resin was 31,000. Terminal hydroxy content was 17 mol%. The number of cuts after storage is shown in Table 3. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 3.

Example II-8

17.2 mg (2 × 10 ^-4 mol) of lithium metaborate was used in place of sodium tetraborate (38 mg, 1 × 10 ^-4 mol), and the amount of boric acid was 3.09 g (5 × 10 -2 mol), Another colorless transparent polycarbonate was prepared through the polycondensation reaction in the same manner as in Example II-1 except for using the other diphenyl carbonate shown. The viscosity-average molecular weight (Mv) of the obtained resin was 28,500. Terminal hydroxy content was 15 mol%. The number of cuts after storage is shown in Table 3. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 3.

Example II-9

The same procedure as in Example II-1 was repeated except that diphenyl carbonate containing a higher amount of specific impurities was used instead of the diphenyl carbonate used in Example II-1 and boric acid was not used. Pale yellow polycarbonate was obtained. The viscosity-average molecular weight (Mv) of the obtained resin was 29,500 and the terminal hydroxy content was 48 mol%. The number of cuts after storage is shown in Table 3. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 3.

Example II-10

The same procedure as in Example II-1 was repeated except that diphenyl carbonate containing a higher amount of specific impurities was used instead of the diphenyl carbonate used in Example II-1. Pale yellow polycarbonate was obtained. The viscosity-average molecular weight (Mv) of the obtained resin was 28,600, and the terminal hydroxy content was 38 mol%. The number of cuts after storage is shown in Table 3. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 3.

Comparative Example II-11

The same procedure as in Example II-1 was repeated except that 0.2 mg (5 × 10 ⁻⁶ moles) of sodium hydroxide was used in place of sodium tetraborate and another diphenyl carbonate having an impurity content shown in Table 3. A light red polycarbonate was obtained. The viscosity-average molecular weight (Mv) of the obtained resin was 30,500, and the terminal hydroxy content was 35 mol%. The number of cuts after storage is shown in Table 3. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 3.

Example II-12

19 mg (5 × 10 ^-5 mol) of sodium tetraborate and 15.3 mg (5 × 10 ^-5 mol) of potassium octaborate are used in place of sodium tetraborate (38 mg, 1 × 10 ^-4 mol) and the amount of boric acid is 40 mg ( 6.5 × 10 ⁻⁴ mole) and other colorless transparent polycarbonate through a polycondensation reaction in the same manner as in Example II-1 except for using another diphenyl carbonate having an impurity content shown in Table 4. Manufactured. The viscosity-average molecular weight (Mv) of obtained resin was 32,000. The cleaved water after storage is shown in Table 4. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 4.

Example II-13

Through polycondensation reaction in the same manner as in Example II-1, except that 50 mg (5 × 10 ⁻⁴ mol) of ammonium hydrogen phosphate was used instead of boric acid and another diphenyl carbonate having an impurity content shown in Table 4 was used. Other colorless transparent polycarbonates were prepared. The viscosity-average molecular weight (Mv) of obtained resin was 29,500. The cleaved water after storage is shown in Table 4. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 4.

Example II-14

3648 g (16 mol) of 2,2-bis (4-hydroxyphenyl) propane, 1272 g (4 mol) of diphenyl isophthalate, 4391.5 g (20.5 mol) of diphenyl carbonate having an impurity content shown in Table 4 38 mg (1 × 10 ⁻⁴ mol) of sodium borate and 30.9 mg (5 × 10 ⁻⁴ mol) of boric acid were placed in the same reactor as in Example II-1. The contents of the reactor were melted in a 180 ° C. nitrogen atmosphere and stirred together for 1 hour. Thereafter, the melted mixture was subjected to the polycondensation treatment in the same manner as in Example II-1 to obtain a polyester carbonate copolymer. The viscosity-average molecular weight (Mv) of the obtained resin was 29,200. The cleaved water after storage is shown in Table 4. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 4.

Example II-15

Another diphenyl carbonate having an impurity content shown in Table 4 was used and 100 ppm of tris (2,4-di-t-butylphenyl) phosphite was added as a phosphorus compound to the raw material used in Example II-1. Except for the production of other colorless transparent polycarbonate in the same manner as in Example II-1. As a hinderphenol, 200 ppm of octadecyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate is added to the polycarbonate when the polycarbonate is in the molten state, thereby producing a polycarbonate composition. Prepared. This polycarbonate composition was extruded into strands and cut using a gear pump. The viscosity-average molecular weight (Mv) of the polycarbonate was 26,700. The cleaved water after storage is shown in Table 4. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 4.

Example II-16

17.2 mg (2 x 10 ^-4 mol) of lithium metaborate was used in place of sodium tetraborate (38 mg, 1 x 10 ^-4 mol), and the amount of boric acid was 61.8 mg (1 x 10 ^-3 mol). Other colorless transparent polycarbonates were prepared through the polycondensation reaction in the same manner as in Example II-1 except that other diphenyl carbonates having the impurity contents indicated were used. The viscosity-average molecular weight (Mv) of obtained resin was 31,000. The cleaved water after storage is shown in Table 4. The initial hue and color tone after 720 hours storage at 160 ° C. are shown in Table 4.

Example III-1

4560 g (20 mol) of 2,2-bis (4-hydroxyphenyl) propane, 4391.5 g (20.5 mol) of diphenyl carbonate having an impurity content shown in Table 5, 489 mg of N, N-dimethyl-4-aminopyridine (4 × 10 ⁻³ moles) and 1.2366 g (2 × 10 ⁻² moles) of boric acid were placed in a bath-type nickel-plating reactor. The contents in the reactor were melted at 160 ° C. in a nitrogen atmosphere and stirred together for 1 hour. The reaction mixture was evacuated in stages, the resulting mixture was raised to distillation and the resulting phenol was distilled off and finally polycondensed under vacuum at 1 Torr for 4 hours at 270 ° C. The resulting mixture was further reacted in a self-cleaning vertical two-screw reactor for 50 minutes to give a colorless transparent polycarbonate. The viscosity-average molecular weight (Mv) of this polycarbonate was 29,000. Terminal hydroxy content was 18 mol%. The number of cleavage after storage showing the thermal deformation degree of the polycarbonate is shown in Table 5. In addition, in order to show the degree of coloring for the storage of the polycarbonate, the first color tone and the color tone after storing at 160 ° C. for 720 hours are shown in Table 5.

Example III-2

736 mg (4 × 10 ⁻³ moles) of carbonate of N, N-dimethyl-4-aminopyridine were used in place of N, N-dimethyl-4-aminopyridine (489 mg, 4 × 10 ⁻³ moles) of boric acid. Other colorless transparent through polycondensation reaction in the same manner as in Example III-1 except that the amount was used at 618 mg (1 × 10 ⁻² mol) and other diphenyl carbonates having impurity contents shown in Table 5 were used. Polycarbonate was prepared. The viscosity-average molecular weight (Mv) of obtained resin was 27,500. Terminal hydroxy content was 11 mol%. The number of cuts after storage is shown in Table 5. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 5.

Example III-3

N, N- dimethyl-4-aminopyridine to 245mg (2 × 10 ^-3 mol) of carbonate and 368mg (2 × 10 ^-3 mol) of N, N- dimethyl-4-aminopyridine N, N- dimethyl- Instead of 4-aminopyridine (489 mg, 4 × 10 ^-3 moles), using 250 mg (4 × 10 ^-3 moles) of boric acid and using other diphenyl carbonates with impurity contents shown in Table 5 Other colorless transparent polycarbonate was prepared through the polycondensation reaction in the same manner as in Example III-1. The viscosity-average molecular weight (Mv) of obtained resin was 28,400. Terminal hydroxy content was 16 mol%. The number of cuts after storage is shown in Table 5. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 5.

Example III-4

1.98 g (2 × 10 ⁻² mol) of ammonium hydrogen phosphate was used in place of boric acid (1.2366 g, 2 × 10 ⁻² mol), except that other diphenyl carbonates having impurity contents shown in Table 5 were used. Another colorless transparent polycarbonate was prepared through the polycondensation reaction in the same manner as in Example III-1. The viscosity-average molecular weight (Mv) of the obtained resin was 26,000. Terminal hydroxy content was 23 mol%. The number of cuts after storage is shown in Table 5. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 5.

Example III-5

2280 g (10 mol) of 2,2-bis (4-hydroxyphenyl) propane, 3400 g (10 mol) of 2,2-bis (4-hydroxy-3-t-butylphenyl) propane, impurity content shown in Table 5 4349 g (20.3 mol) of diphenyl carbonate with 489 mg (4 × 10 ⁻³ mol) of N, N-dimethyl-4-aminopyridine and 1.2366 g (2 × 10 ⁻² mol) of boric acid were prepared in Example III-1. Into the same reactor as was used for. The contents of the reactor were treated in the same manner as in Example III-1 to obtain a polyester carbonate copolymer (optional ratio: about 50%). The viscosity-average molecular weight of obtained resin was 26,500. Terminal hydroxy content was 18 mol%. The number of cuts after storage is shown in Table 5. Table 5 shows the initial color tone and the color tone after storage at 160 ° C. for 720 hours. The arbitrary proportion of the polyester carbonate copolymer was determined by ¹³ C-NMR spectroscopic analysis of the copolymer based on the chemical shift of carbon in the carbonate bond.

Example III-6

3648 g (16 mol) of 2,2-bis (4-hydroxyphenyl) propane, 1272 g (4 mol) of diphenyl isophthalate, 4391.5 g (20.5 mol) of diphenyl carbonate having an impurity content shown in Table 5, N 489 mg (4 × 10 ⁻³ mol) of N-dimethyl-4-aminopyridine and 1.2366 g (2 × 10 ⁻² mol) of boric acid were placed in the same reactor as in Example III-1. The contents of the reactor were melted in a 180 ° C. nitrogen atmosphere and stirred together for 1 hour. Thereafter, the melted mixture was treated in the same manner as in Example III-1 to polycondensate, thereby obtaining a polyester carbonate copolymer. The viscosity-average molecular weight (Mv) of the obtained resin was 29,200. Terminal hydroxy content was 16 mol%. The number of cuts after storage is shown in Table 5. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 5.

Example III-7

Another diphenyl carbonate having an impurity content shown in Table 5 was used and 100 ppm of tris (2,4-di-t-butylphenyl) phosphite was added as a phosphorus compound to the raw material used in Example III-1. Except for the production of other colorless transparent polycarbonate in the same manner as in Example III-1. As a hinderphenol, 200 ppm of octadecyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate is added to this polycarbonate when the polycarbonate is in the molten state The composition was prepared. This polycarbonate composition was extruded into strands and cut using a gear pump. The viscosity-average molecular weight (Mv) of the polycarbonate was 26,700. Terminal hydroxy content was 17 mol%. The number of cuts after storage is shown in Table 5. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 5.

Example III-8

4560 g (20 mol) of 2,2-bis (4-hydroxyphenyl) propane, 4391.5 g (20.5 mol) of diphenyl carbonate having an impurity content shown in Table 5, 489 mg of N, N-dimethyl-4-aminopyridine (4 × 10 ⁻³ mol) and 24.732 g (4 × 10 ⁻¹ mol) of boric acid were placed in the same reactor as in Example III-1. The contents in the reactor were melted at 200 ° C. in a nitrogen atmosphere and stirred together for 1 hour. The reaction mixture was evacuated in stages, the resulting mixture was raised to distillation and the resulting phenol was distilled off and finally polycondensed under vacuum at 1 Torr for 4 hours at 270 ° C. The resulting mixture was further reacted in a self-cleaning vertical two-screw reactor for 80 minutes to yield a colorless transparent polycarbonate. The viscosity-average molecular weight (Mv) of obtained resin was 23,000. Terminal hydroxy content was 28 mol%. The number of cuts after storage is shown in Table 5. Table 5 shows the initial color tone and the color tone after storage at 160 ° C. for 720 hours.

Example III-9

The same procedure as in Example III-1 was repeated except that diphenyl carbonate containing a higher amount of specific impurities was used instead of the diphenyl carbonate used in Example III-1 and boric acid was not used. Pale yellow polycarbonate was obtained. The viscosity-average molecular weight (Mv) of the obtained resin was 29,500 and the terminal hydroxy content was 48 mol%. The number of cuts after storage is shown in Table 5. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 5.

Example III-10

The same procedure as in Example III-1 was repeated except that diphenyl carbonate containing a higher amount of specific impurities was used in place of the diphenyl carbonate used in Example III-1. Pale yellow polycarbonate was obtained. The viscosity-average molecular weight (Mv) of the obtained resin was 28,600, and the terminal hydroxy content was 38 mol%. The number of cuts after storage is shown in Table 5. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 5.

Example III-11

Example III-1 except that diphenyl carbonate containing a higher amount of specific impurities was used in place of the diphenyl carbonate used in Example III-1 and 136 g (2.2 mol) of boric acid was used. The same procedure was repeated. Pale yellow polycarbonate was obtained. The viscosity-average molecular weight (Mv) of the obtained resin was 14,000, and the terminal hydroxy content was 35 mol%. The number of cuts after storage is shown in Table 5. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 5.

Comparative Example III-12

Example III, except that 0.2 mg (5 × 10 ⁻⁶ mol) of sodium hydroxide was used in place of N, N-dimethyl-4-aminopyridine) and other diphenyl carbonates having impurity contents shown in Table 5 were used. The procedure was repeated as -1. A light red polycarbonate was obtained. The viscosity-average molecular weight (Mv) of the obtained resin was 30,500, and the terminal hydroxy content was 45 mol%. The number of cuts after storage is shown in Table 5. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 5.

Example III-13

245 mg (2 x 10 ^-3 mol) of N, N-dimethyl-4-aminopyridine and 368 mg (2 x 10 ^-3 mol) of carbonate of N, N-dimethyl-4-aminopyridine were added to N, N-dimethyl- Instead of 4-aminopyridine (489 mg, 4 × 10 ^-3 moles), using 250 mg (4 × 10 ^-3 moles) of boric acid and other diphenyl carbonates with impurity contents shown in Table 6 Other colorless transparent polycarbonate was prepared through the polycondensation reaction in the same manner as in Example III-1. The viscosity-average molecular weight (Mv) of the obtained resin was 28,400. The number of cuts after storage is shown in Table 6. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 6.

Example III-14

Example except that 1.98 g (2 × 10 ⁻² mol) of ammonium hydrogen phosphate was used in place of boric acid (1.2366 g, 2 × 10 ⁻² mol) and other diphenyl carbonates having impurity contents shown in Table 6 were used. Another colorless transparent polycarbonate was prepared through polycondensation in the same manner as in III-1. The viscosity-average molecular weight (Mv) of the obtained resin was 26,000. The number of cleavage after storage is shown in Table 6. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 6.

Example III-15

2280 g (10 mol) of 2,2-bis (4-hydroxyphenyl) propane, 3400 g (10 mol) of 2,2-bis (4-hydroxy-3-t-butylphenyl) propane, impurity content shown in Table 6 4349 g (20.3 mol) of diphenyl carbonate with 489 mg (4 × 10 ⁻³ mol) of N, N-dimethyl-4-aminopyridine and 1.2366 g (2 × 10 ⁻² mol) of boric acid were prepared in Example III-1. Into the same reactor as was used for. Reactor copolymer was obtained (optional ratio: about 50%). The viscosity-average molecular weight of obtained resin was 26,500. The number of cuts after storage is shown in Table 6. Table 6 shows the initial color tone and the color tone after storage at 160 ° C. for 720 hours. The arbitrary proportion of the polyester carbonate copolymer was determined by ¹³ C-NMR spectroscopic analysis of the copolymer based on the chemical shift of carbon in the carbonate bond.

Example III-16

3648 g (16 moles) of 2,2-bis (4-hydroxyphenyl) propane, 1272 g (4 moles) of diphenyl isophthalate, 4391.5 g (20.5 moles) of diphenyl carbonate having an impurity content shown in Table 6, N 489 mg (4 × 10 ⁻³ mol) of N-dimethyl-4-aminopyridine and 1.2366 g (2 × 10 ⁻² mol) of boric acid were placed in the same reactor as in Example III-1. The contents of the reactor were melted in a 180 ° C. nitrogen atmosphere and stirred together for 1 hour. Thereafter, the melted mixture was treated in the same manner as in Example III-1 to polycondensate, thereby obtaining a polyester carbonate copolymer. The viscosity-average molecular weight (Mv) of the obtained resin was 29,200. The number of cuts after storage is shown in Table 6. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 6.

Example III-17

The same procedure as in Example III-1 was used except that 12.366 g (2 × 10 ⁻² mol) of boric acid was used and other diphenyl carbonates having impurity contents shown in Table 6 were used.

Repeated. A colorless transparent polycarbonate was obtained. The viscosity-average molecular weight (Mv) of the obtained resin was 18,500. The number of cuts after storage is shown in Table 6. The initial hue and hue after storage at 160 ° C. for 720 hours are shown in Table 6.

Example III-18

4560 g (20 moles) of 2,2-bis (4-hydroxyphenyl) propane, 4391.5 g (20.5 moles) of diphenyl carbonate with impurity content shown in Table 7, 489 mg (1 × 10 ^-3 moles) N, N-dimethyl-4-aminopyridine and 70 mg (1.13 mmol) of boric acid were added to a crude nickel plating reactor. The contents of the reactor were melted in a nitrogen atmosphere at 160 ° C. and stirred together for 1 hour. The reaction mixture was gradually evacuated to raise the temperature of the resulting mixture, and the resulting phenol was distilled off, and finally polycondensation was carried out at 270 DEG C under vacuum of 1 Torr for 4 hours. The resulting mixture was further reacted for 50 minutes in a self-cleaning vertical two-helix reactor to give a colorless transparent polycarbonate. The viscosity-average molecular weight (Mv) of the polycarbonate was 29,000. The number of cleavage after storage which shows the thermal strain of the polycarbonate is shown in Table 7. In addition, in order to show the coloration of the polycarbonate with the storage, the color tone after the initial color tone and storage at 160 ℃ for 720 hours is shown in Table 7.

Example III-19

736 mg (4 × 10 ^-3 moles) of carbonate of N, N-dimethyl-4-aminopyridine was used in place of N, N-dimethyl-4-aminopyridine (489 mg, 4 × 10 ^-3 moles) and boric acid Colorless transparent polycarbonate by polycondensation reaction in the same manner as in Example III-18, except that 30 mg (0.49 mmoℓ) of was used and another diphenyl carbonate having an impurity content shown in Table 7 was used. Nate was prepared. The viscosity-average molecular weight (Mv) of obtained resin was 27,500. The number of cuts after storage is shown in Table 7. In addition, the hue after initial storage and storage at 160 ° C. for 720 hours is shown in Table 7.

Example III-20

245 mg (2x10 ^-3 mol) of N, N-dimethyl-4-aminopyridine and 368 mg (2x10 ^-3 mol) of carbonate of N, N-dimethyl-4-aminopyridine Except for using dimethyl-4-aminopyridine (489mg, 4x10 ^-3 mol), using 50mg (0.81mmol) of boric acid, and using other diphenyl carbonates having impurity contents shown in Table 7. Then, another colorless transparent polycarbonate was prepared by the polycondensation reaction in the same manner as in Example III-18. The viscosity-average molecular weight (Mv) of obtained resin was 28,400. The number of cuts after storage is shown in Table 7. In addition, the hue after the initial color tone and storage at 160 ° C. for 720 hours is shown in Table 7.

Example III-21

112 mg (1.13 mmol) of ammonium hydrogen phosphate was used in place of boric acid (70 mg, 1.13 mmol) and used in the same manner as in Example III-18, except that other diphenyl carbonates having impurity contents shown in Table 7 were used. Another colorless transparent polycarbonate was prepared by polycondensation. The viscosity-average molecular weight (Mv) of obtained resin was 26,000. The number of cuts after storage is shown in Table 7. In addition, the hue after the initial color tone and storage at 160 ° C. for 720 hours is shown in Table 7.

Example III-22

2280 g (10 moles) of 2,2-bis (4-hydroxyphenyl) propane, 3400 g (10 moles) of 2,2-bis (4-hydroxy-3-t-butylphenyl) propane, shown in Table 7 4349 g (20.3 moles) of diphenylcarbonate, 489 mg (4 x 10 ^-3 moles) of N, N-dimethyl-4-aminopyridine and 70 mg (1.13 mmol) of boric acid with impurity content Put into the same reactor as used for. The contents in the reactor were treated in the same manner as in Example III-18 to prepare a polyester carbonate copolymer (optional ratio: about 50%). The viscosity-average molecular weight (Mv) of obtained resin was 26,500. The number of cuts after storage is shown in Table 7. In addition, the hue after initial storage and storage at 160 ° C. for 720 hours is shown in Table 7. The arbitrary proportion of the polyester carbonate copolymer was measured by ¹³ C-NMR spectroscopic analysis of the copolymer based on the chemical shift of carbon in the carbonate bond.

Example III-23

3648 g (16 moles) of 2,2-bis (4-hydroxyphenyl) propane, 1272 g (4 moles) of diphenyl isophthalate, 4391.5 g (20.5 moles) of diphenyl carbo with impurity contents shown in Table 7 Nate, 489 mg (4 × 10 ⁻³ mol) of N, N-dimethyl-4-aminopyridine, and 70 mg (1.13 mmol) of boric acid were placed in the same reactor as in Example III-18. The reactor contents were melted in a nitrogen atmosphere at 180 ° C. and stirred together for 1 hour. Thereafter, the melt mixture was treated in the same manner as in Example III-18 to perform a polycondensation reaction to obtain a polyester carbonate copolymer. The viscosity-average molecular weight (Hv) of obtained resin was 29,200. The number of cuts after storage is shown in Table 7. Also shown in Table 7 are the initial hue and the hue after storage at 160 ° C. for 720 hours.

Example III-24

Other phosphorus compounds were added in the same manner as in Example III-18, except that 100 ppm of tris (2,4-di-t-butylphenyl) phosphite was added to the raw materials used in Example III-18. A colorless transparent polycarbonate was prepared. When the polycarbonate is in the molten state, 200 ppm of octadecyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate is added to the obtained polycarbonate to form a polycarbonate composition. Was prepared. The polycarbonate composition was extruded with a gear pump to strand and cut. The viscosity-average molecular weight (Mv) of the polycarbonate was 26,700. The number of cuts after storage is shown in Table 7. In addition, the hue after the initial color tone and storage at 160 ° C. for 720 hours is shown in Table 7.

Example III-25

The same procedure as in Example III-18 was repeated except that another diphenyl carbonate having an impurity content shown in Table 7 was used and no boric acid was used. A colorless and transparent polycarbonate was obtained. The viscosity-average molecular weight (Mv) of obtained resin was 29,500. The number of cuts after storage is shown in Table 7. In addition, the hue after the initial color tone and storage at 160 ° C. for 720 hours is shown in Table 7.

Example III-26

The same procedure as in Example III-18 was repeated except that diphenyl carbonate containing higher amounts of specific impurities was used instead of the diphenyl carbonate used in Example III-18. Pale yellow polycarbonate was obtained. The viscosity-average molecular weight (Mv) of obtained resin was 28,600. The number of cuts after storage is shown in Table 7. In addition, the hue after the initial color tone and storage at 160 ° C. for 720 hours is shown in Table 7.

Example III-27

The same procedure as in Example III-18 was repeated except that another diphenyl carbonate having the impurity content shown in Table 7 was used and the amount of boric acid was 70 mg (11.3 mmol). A colorless transparent polycarbonate was obtained. The viscosity-average molecular weight (Mv) of obtained resin was 18,500. The number of cuts after storage is shown in Table 7. In addition, the hue after the initial color tone and storage at 160 ° C. for 720 hours is shown in Table 7.

Comparative Example III-28

Example III except that 0.2 mg (5 × 10 ⁻⁶ moles) of sodium hydroxide was used instead of N, N-dimethyl-4-aminopyridine and other diphenyl carbonates having impurity contents shown in Table 7 The same method as for -18 was repeated. Polycarbonate was obtained. The viscosity-average molecular weight (Mv) of obtained resin was 30,500. The number of cuts after storage is shown in Table 7. In addition, the hue after the initial color tone and storage at 160 ° C. for 720 hours is shown in Table 7.

Example IV-1

22.8 g (0.1 mole) 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.164 g (2 x 10 ^-2 mole per mole of BPA), 0.00082 g (BPA) 21.96 g (0.1025 mole) of diphenyl carbonate having 1 × 10 ⁻⁴ mole) of sodium acetate and the impurity contents shown in Table 8 were added to the reactor and stirred together at 180 ° C. for 1 hour. The temperature of the obtained mixture was raised while gradually evacuating the reaction system. The mixture was polycondensed under vacuum of 0.1 Torr at 270 ° C. for 1 hour while finally removing the resulting phenol by distillation. Thus, colorless and transparent polycarbonate was obtained. Its viscosity-average molecular weight (Mv) was 27,600. Its glass transition point was 150 ° C. and the terminal hydroxy content was 28 mol%. The hue after initial storage and storage at 160 ° C. for 720 hours is shown in Table 9 to show the degree of coloration upon its storage.

Example IV-2

0.00122 g (1 × 10 ⁻⁴ mole per mole of BPA) 4-dimethylaminopyridine is used in place of 2-methylimidazole and 0.00098 g (1 × 10 ⁻⁴ mole per mole of BPA) Other colorless transparent polycarbonates were prepared by polycondensation in the same manner as in Example IV-1, except that other diphenyl carbonates having impurity contents shown in Table 8 were used. Its viscosity-average molecular weight (Mv) was 27,000. Its glass transition point was 150 ° C. and the terminal hydroxyl content was 25 mol%. The initial hue and color tone after storage at 160 ° C. for 720 hours are shown in Table 9.

Example IV-3

11.4 g (50 mole% of dihydric phenol used) 2,2-bis (4-hydroxyphenyl) propane, 17.0 g (50 mole% of dihydric phenol used) 2,2-bis- (4 -Hydroxy-3-t-butylphenyl) propane, 0.00122 g (bisphenol, i.e., 1 x 10 ^-4 moles per mole of dihydric phenol), 0.000066 g (1 of bisphenol, i.e. bivalent phenol) 1 × 10 ⁻⁵ mole) of lithium acetate and 21.96 g (0.1025 mole) of diphenyl carbonate having impurity contents shown in Table 8 were added to the reactor and stirred together in a nitrogen atmosphere for 2 hours. The obtained mixture was polycondensed in the same manner as in Example IV-1 to give a colorless transparent polycarbonate. Its viscosity-average molecular weight (Mv) was 24,500 and the glass transition point was 128 ° C. Its terminal hydroxyl content was 23 mol%. In addition, the hue after initial color tone and storage at 160 ° C. for 720 hours is shown in Table 9.

Example IV-4

0.00091 g (1 × 10 ⁻⁴ mole per mole of BPA) tetramethylammonium hydroxide in place of 2-methylimidazole and 0.00098 g (1 × 10 ⁻⁴ mole per mole of BPA) potassium acetate And polycondensation reaction in the same manner as in Example IV-1, except that other raw material diphenyl carbonate having impurity contents shown in Table 8 was used, Stirring together in a nitrogen atmosphere to produce other colorless transparent polycarbonate. Its viscosity-average molecular weight (Mv) was 27,800 and the glass transition point was 151 ° C. Its terminal hydroxy content was also 21 mol%. The initial hue and color tone after storage at 160 ° C. for 720 hours are shown in Table 9.

Example IV-5

22.8 g (0.1 mole) of 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.0024 g (2 x 10 ^-4 mole per mole of BPA) and impurities shown in Table 8 21.96 g (0.1025 mole) of diphenyl carbonate having a content was placed in a reactor and the mixture was polycondensed in the same manner as in Example IV-1 to obtain a colorless transparent polycarbonate. Its viscosity-average molecular weight (Mv) was 29,000 and the glass transition point was 150 ° C. Its terminal hydroxy content was also 26 mol%. The initial hue and color tone after storage at 160 ° C. for 720 hours are shown in Table 9.

Comparative Example IV-6

22.8 g (0.1 mole) 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.0024 g (2 x 10 ^-4 mole per mole of BPA), 0.00098 g ( 1 x 10 ^-4 moles of potassium acetate per mole of BPA and 21.96 g (0.1025 moles) of diphenylcarbonate having an impurity content shown in Table 8 were placed in a reactor and the resulting mixture was prepared as in Example IV-1. It polycondensed by the method and obtained polycarbonate. Its viscosity-average molecular weight (Mv) was 19,500 and the glass transition point was 130 ° C. Its terminal hydroxy content was 35 mol%. The initial hue and color tone after storage at 160 ° C. for 720 hours are shown in Table 9.

Comparative Example IV-7

22.8 g (0.1 mole) 2,2-bis (4-hydroxyphenyl) propane (BPA), 0.0024 g (2 x 10 ^-4 mole per mole of BPA), 0.00098 g ( 1 x 10 ^-4 mole of potassium acetate per mole of BPA and 21.96 g (0.1025 mole) of diphenylcarbonate having an impurity content shown in Table 8 were placed in a reactor and the resulting mixture was prepared in the same manner as in Example IV-1. Polycondensation was carried out to obtain polycarbonate. Its viscosity-average molecular weight (Mv) was 24,500 and the glass transition point was 145 ° C. Its terminal hydroxy content was 28 mol%. The initial hue and color tone after storage at 160 ° C. for 720 hours are shown in Table 9.

In accordance with the present invention, a raw material containing a small amount of specific impurities and a catalyst system are used as (a) basic nitrogen compounds and / or (b) alkali metal compounds and / or alkaline earth metal compounds to substantially eliminate toxic phosgene without using toxic phosgene. High molecular weight, colorless transparent polycarbonate can be prepared.

Also in accordance with the present invention a borate or an electron donating amine and / or a salt thereof as a catalyst and an acidic material are used to prepare a thermally stable polycarbonate or a thermally stable polycarbonate composition without the use of toxic phosgene. can do.

Claims (16)

A method for producing a thermostable polycarbonate by melt-polycondensing a carbonic acid diester and a dihydric phenol, characterized by using a compound selected from the group consisting of electron donating amines and salts thereof as a catalyst. The thermostable polycarbonate according to claim 1, wherein the amount of the compound selected from the group consisting of an electron donating amine and a salt thereof used as a catalyst is 10 ^-6 to 10 ^-1 mole per mole of the divalent phenol. How to prepare. The process of claim 1 wherein an acidic material capable of neutralizing the catalyst is used. 4. A process according to claim 3, wherein the amount of acid is 0.01 to 500 times the amount of a compound selected from the group consisting of electron donating amines and salts thereof used as catalysts in molar ratios. . The method of producing a thermostable polycarbonate according to claim 4, wherein the amount of acidic substance is 0.01 to 0.5 times the amount of a compound selected from the group consisting of an electron donating amine and a salt thereof used as a catalyst in a molar ratio. . The method of producing a thermostable polycarbonate according to claim 4, wherein the amount of acidic substance is 1 to 20 times the amount of a compound selected from the group consisting of an electron donating amine and a salt thereof used as a catalyst in molar ratio. . 4. The process of claim 3 wherein the acidic material is boric acid or ammonium hydrogen phosphite. The method of claim 1, wherein the carbonic acid diester has a total water content of 0.3% by weight or less, a chlorine content of 3 ppm or less, a sodium content of 1 ppm or less, an iron content of 1 ppm or less, and a copper ion content of 1 ppm or less , Phosphorus ion content of 20 ppm or less, phenyl salicylate of 50 ppm or less, o-phenoxybenzoic acid and phenyl o-phenoxybenzoate combined, tin ion content of 5 ppm or less, and methylphenyl carbonate content of 50 ppm or less Method for producing a thermostable polycarbonate, characterized in that. The method of claim 1, wherein the carbonic acid diester is obtained by hydrolysis up to 3 ppm chlorine content, up to 1 ppm sodium ion content, up to 1 ppm iron ion content, and up to 50 ppm phenyl salicylate, o-phenoxybenzoic acid and A process for producing a thermostable polycarbonate, characterized in that it has a combined content of phenyl o-phenoxybenzoate. The process of claim 1 wherein the carbonic acid diester is used in an amount of 1.01 to 1.5 moles per mole of dihydric phenol. 2. The process of claim 1 wherein the resulting polycarbonate has a terminal hydroxy concentration of 3 to 30 mole percent. The method of claim 1, wherein the dihydric phenol is a compound selected from the group consisting of the compounds represented by the following Chemical Formulas 1 to 4. (Formula 1)

(Formula 2)

(Formula 3)

(Formula 4)

(Wherein R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are each a hydrogen atom, a linear or branched alkyl group or a phenyl group of 1 to 8 carbon atoms, X is a halogen atom, n is 0 or 1 to 4) And m is an integer from 1 to 4.) The method of producing a thermostable polycarbonate according to claim 1, wherein the copolymer is prepared using at least two divalent phenols or at least two carbonic acid diesters. 2. A process according to claim 1, wherein a phosphorus compound or hinderphenol is used. A method for producing a thermostable polycarbonate composition, comprising adding an acidic substance capable of neutralizing a catalyst to a polycarbonate prepared by the method of claim 1. A process for producing a thermostable polycarbonate composition, comprising adding a phosphorus compound or a hinderphenol to the polycarbonate prepared by the method of claim 1.