JPH0753706A - Production of polycarbonate - Google Patents

Abstract

PURPOSE:To produce a high-quality polycarbonate excellent in heat and hydrolysis resistances with good productivity. CONSTITUTION:In producing a polycarbonate from a dihydric phenol and a carbonic diester through transesterification in the presence of a transesterification catalyst, an aromatic halogen or nitro compound having electron attracting groups at the ortho or para positions is added to the polymerization system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing polycarbonate, which is preferably used as a raw material in the electric / electronic fields and the automobile field. More specifically, the present invention relates to a method for producing a polycarbonate that can provide a high-quality polycarbonate with high productivity.

[0002]

2. Description of the Related Art Polycarbonate is an engineering plastic excellent in transparency, heat resistance and impact resistance.
Currently, it is a resin widely used in the industrial field. However, in the interfacial polycondensation method, there is a problem that toxic phosgene gas and methylene chloride as a chlorine impurity source are used in the manufacturing process, and improvement of the manufacturing method has been conventionally desired. In order to solve this problem, recently, so-called melt polymerization method utilizing transesterification reaction between carbonic acid diester and dihydric phenol has been actively developed.

In the production of polycarbonate by transesterification reaction, a basic catalyst such as an alkali metal or alkaline earth metal carbonate, acetate or hydroxide is used as a reaction catalyst. In addition, recently, for example, a method using a barium compound and a borate ester as a catalyst described in JP-A-3-203928, an electron-donating amine compound and IIb described in JP-A-5-1145, etc. Researches on new catalyst systems such as a method using a compound containing an element of IVb or Vb as a catalyst are also being actively conducted. However, these catalysts inherently lower the chemical stability of carbonate bonds, and therefore, when these catalysts remain in the final product polycarbonate, physical properties such as heat resistance and hydrolysis resistance. Will lead to a decline.

In order to solve this problem, for example, JP-A-4-175368 proposes a method in which an acidic substance is added to the reaction system at the end of the polymerization to neutralize the basic polymerization catalyst. However, this method cannot be said to be a sufficient method because it has problems such as the need to further detoxify the excess acidic substance used for neutralization.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing a polycarbonate capable of producing a high-quality polycarbonate having excellent heat resistance and hydrolysis resistance with high productivity.

[0006]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned object, the present inventors have found that when a polycarbonate is produced by a transesterification method, a specific aromatic compound is added to a polymerization system. As a result, it was found that a polycarbonate having excellent heat resistance and hydrolysis resistance can be produced with high productivity, and the present invention has been completed based on this finding.

That is, according to the present invention, in producing a polycarbonate from a dihydric phenol and a carbonic acid diester by transesterification in the presence of a transesterification catalyst, an aromatic halogen compound or an aromatic nitro compound having an electron withdrawing group at the ortho or para position is used. The present invention provides a method for producing a polycarbonate, which comprises adding a compound to a polymerization system.

The dihydric phenol used in the present invention is not particularly limited, and various dihydric phenols including conventionally known ones can be used.
Only one species may be used alone, or two or more species may be used in combination.

Examples of the dihydric phenol preferably used in the present invention include, for example, 4,4-dihydroxybiphenyl, 4,4'-dihydroxy-2,2'-dimethylbiphenyl and 4,4'-dihydroxy-3. , 3'-Dimethylbiphenyl, 4,4'-dihydroxy-3,3'-dicyclohexylbiphenyl, 3,3'-difluoro-4,
Dihydroxybiphenyls such as 4'-dihydroxybiphenyl; bis (hydroxy) such as bis (4-hydroxyphenyl) ether, bis (3-fluoro-4-hydroxyphenyl) ether, bis (4-hydroxy-3-methylphenyl) ether Aryl) ethers; 4,
Bis (hydroxyaryl) ketones such as 4′-dihydroxybenzophenone; Bis (hydroxyaryl) sulfides such as bis (4-hydroxyphenyl) sulfide and bis (3-methyl-4-hydroxyphenyl) sulfide; Bis (4-) Bis (hydroxyaryl) sulfoxides such as hydroxyphenyl) sulfoxide, bis (3-methyl-4-hydroxyphenyl) sulfoxide, bis (3-phenyl-4-hydroxyphenyl) sulfoxide; bis (4-hydroxyphenyl) sulfone, bis (3-methyl-4-hydroxyphenyl) sulfone, bis (3-phenyl-4-hydroxyphenyl)
Bis (hydroxyaryl) sulfones such as sulfone;
Bis (4-hydroxyphenyl) methane, bis (3-methyl-4-hydroxyphenyl) methane, bis (3-chloro-4-hydroxyphenyl) methane, bis (3,5
-Dibromo-4-hydroxyphenyl) methane, 1,1
-Bis (4-hydroxyphenyl) -1-phenylmethane, 1,1-bis (4-hydroxyphenyl) -1,1
-Diphenylmethane, 1,1-bis (2-tert-butyl-4-hydroxy-5-methylphenyl) -1-phenylmethane, 1,1-bis (4-hydroxyphenyl) ethane, 1,1-bis (2 -Tert-butyl-4
-Hydroxy-3-methylphenyl) ethane, 1-phenyl-1,1-bis (3-fluoro-4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 2- (3-Methyl-4-hydroxyphenyl) -2- (4-hydroxyphenyl)
-1-phenylethane, 1,1-bis (4-hydroxyphenyl) -2,2,2-triphenylethane, 2,2
-Bis (4-hydroxyphenyl) propane, 2,2-
Bis (3-methyl-4-hydroxyphenyl) propane, 2,2-bis (2-methyl-4-hydroxyphenyl) propane, 2,2-bis (3,5-dimethyl-4-)
Hydroxyphenyl) propane, 1,1-bis (2-t
ert-butyl-4-hydroxy-5-methylphenyl) propane, 2,2-bis (3-chloro-4-hydroxyphenyl) propane, 2,2-bis (3-fluoro-4-hydroxyphenyl) propane, 2 , 2-bis (3-bromo-4-hydroxyphenyl) propane,
2,2-bis (3,5-difluoro-4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-)
4-hydroxyphenyl) propane, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, 2,2-bis (3-bromo-4-hydroxy-5)
Chlorophenyl) propane, 2,2-bis (3-hydroxyphenyl) hexafluoropropane, 2,2-bis (3-phenyl-4-hydroxyphenyl) propane,
2,2-bis (4-hydroxyphenyl) butane, 2,
2-bis (3-methyl-4-hydroxyphenyl) butane, 1,1-bis (2-butyl-4-hydroxy-5-)
Methylphenyl) butane, 1,1-bis (2-tert)
-Butyl-4-hydroxy-5-methylphenyl) butane, 1,1-bis (2-tert-butyl-4-hydroxy-5-methylphenyl) isobutane, 1,1-bis (2-tert-amyl-4) -Hydroxy-5-methylphenyl) butane, 2,2-bis (3,5-dichloro-
4-hydroxyphenyl) butane, 2,2-bis (3,3
5-dibromo-4-hydroxyphenyl) butane, 2,
2-bis (4-hydroxyphenyl) -4-methylpentane, 4,4-bis (4-hydroxyphenyl) heptane, 1,1-bis (2-tert-butyl-4-hydroxy-5-methylphenyl) heptane , 2-bis (4-hydroxyphenyl) octane, bis (hydroxyaryl) alkanes such as 1,2-bis (4-hydroxyphenyl) ethane; 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (3-
Methyl-4-hydroxyphenyl) cyclohexane,
Bis (hydroxyaryl) cycloalkanes such as 1,1-bis (3-cyclohexyl-4-hydroxyphenyl) cyclohexane and 1,1-bis (3-phenyl-4-hydroxyphenyl) cyclohexane; 1,1′-
Bis (4-hydroxyphenyl) -p-diisopropylbenzene, 1,1'-bis (4-hydroxyphenyl)
Bis {(hydroxyaryl) methyl} benzenes such as -m-diisopropylbenzene; resorcin, 3-methylresorcin, 3-ethylresorcin, 3-propylresorcin, 3-butylresorcin, 3-tert-butylresorcin, 3-phenyl Resorcin, 3-cumylresorcin, 2,3,4,6-tetrafluororesorcin, 2,3,4,6-tetrabromoresorcin, catechol, hydroquinone, 3-methylhydroquinone, 3
-Ethylhydroquinone, 3-propylhydroquinone, 3-butylhydroquinone, 3-tert-butylhydroquinone, 3-phenylhydroquinone, 3-cumylhydroquinone, 2,3,5,6-tetramethylhydroquinone, 2,3,4 Examples include unsubstituted or halogen- and alkyl-substituted dihydroxybenzenes such as 6-tetra-tert-butylhydroquinone, 2,3,5,6-tetrafluorohydroquinone and 2,3,5,6-tetrabromohydroquinone. .

Further, in the present invention, as the dihydric phenol, 2,2,2 ', 2'-tetrahydro-3,
3,3 ', 3'-tetramethyl-1,1'-spirobi-
Spiro compounds such as [1H-indene] -6,6'-diol can also be used.

Further, a dihydric alcohol such as a hydroxyalkyl ester of biphenyldicarboxylic acid or a hydroxyalkyl ester of bicyclohexyldicarboxylic acid may be used instead of a part of the above dihydric phenol. In this case, polyester carbonate is obtained.

The carbonic acid diester used in the present invention is not particularly limited, and various carbonic acid diesters including known ones can be used. The carbonic acid diesters may be used alone or in combination of two or more. You may use together.

The carbonic acid diester used in the present invention includes a diaryl carbonate compound, a dialkyl carbonate compound, and an alkyl aryl carbonate compound. Specific examples of the carbonic acid diaryl compound include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (biphenylyl) carbonate and the like. In addition, specific examples of the dialkyl carbonate compound include diethyl carbonate, dimethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate and the like. On the other hand, specific examples of the alkyl aryl carbonate compound include methylphenyl carbonate, ethylphenyl carbonate, butylphenyl carbonate and cyclohexylphenyl carbonate. Of these,
Diphenyl carbonate is preferably used.

The amount of the carbonic acid diester used is usually 0.90 to 1.50 mol, preferably 0.95 to 1.25 mol, per 1 mol of the dihydric phenol.

If necessary, a dicarboxylic acid or a dicarboxylic acid ester may be used instead of part of the carbonic acid diester. In this case, polyester carbonate is obtained. Examples of the dicarboxylic acid and dicarboxylic acid ester include aromatic dicarboxylic acids such as isophthalic acid, terephthalic acid, diphenyl isophthalate, diphenyl terephthalate, isophthalic acid dichloride, and terephthalic acid dichloride; succinic acid, glutaric acid, adipic acid, pimelic acid. , Aliphatic acids such as speric acid, azelaic acid, sevanic acid, decanedioic acid, dodecanedioic acid, diphenyl sebacate, diphenyl decanedioate; cyclopropanedicarboxylic acid, 1,2-cyclobutanedicarboxylic acid, 1,3- Cyclobutanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,
3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, diphenyl cyclopropanedicarboxylic acid, diphenyl 1,2-cyclobutanedicarboxylic acid,
1,3-Cyclobutanedicarboxylic acid diphenyl, 1,2
Examples thereof include alicyclic dicarboxylic acids such as diphenyl cyclopentanedicarboxylate, diphenyl 1,2-cyclohexanedicarboxylate, diphenyl 1,3-cyclohexanedicarboxylate, and diphenyl 1,4-cyclohexanedicarboxylate. The amount of the dicarboxylic acid and dicarboxylic acid ester used is, for example, 50 mol% or less, preferably 30 mol% or less of the carbonic acid diester.

The transesterification catalyst used in the present invention is not particularly limited as long as it is a commonly used catalyst. A basic compound is preferably used. In particular,
Nitrogen-containing basic compounds such as alkali metal compounds and alkaline earth metal compounds, amines and quaternary ammonium salts are preferably used.

Specific examples of the alkali metal compound and alkaline earth metal compound include organic acid salts, inorganic acid salts, oxides, hydroxides, hydrides and alcoholates of alkali metals and alkaline earth metals. To be

More specifically, as the alkali metal compound, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium hydrogen carbonate, potassium hydrogen carbonate, lithium hydrogen carbonate, sodium carbonate, potassium carbonate, lithium carbonate, sodium acetate, Potassium acetate, lithium acetate, sodium stearate, potassium stearate, lithium stearate, sodium borohydride, lithium borohydride, sodium phenyl borohydride, sodium benzoate, potassium benzoate, lithium benzoate, disodium hydrogen phosphate , Dipotassium hydrogen phosphate, dilithium hydrogen phosphate, disodium salt of bisphenol A, dipotassium salt or dilithium salt, sodium salt, potassium salt or lithium salt of phenol, or cesium fluoride, potassium fluoride Such as fluoride and the like can be mentioned.

As the alkaline earth metal compound,
Specifically, calcium hydroxide, barium hydroxide, magnesium hydroxide, strontium hydroxide, calcium hydrogen carbonate, barium hydrogen carbonate, magnesium hydrogen carbonate, strontium hydrogen carbonate, calcium carbonate, barium carbonate, magnesium carbonate, strontium carbonate, calcium carbonate, Examples thereof include barium acetate, magnesium acetate, strontium acetate, calcium stearate, barium stearate, magnesium stearate, and strontium stearate.

Specific examples of the nitrogen-containing basic compound include
Is tetramethylammonium hydroxide, tetrae
Tylammonium hydroxide, tetrabutylammoni
Um hydroxide, trimethylbenzyl ammonium
Alkyl, aryl, araryl groups such as droxide
Ammonium hydroxides, such as trimethyl
Luamine, triethylamine, dimethylbenzylami
And tertiary amines such as triphenylamine, R₂NH
(In the formula, R is alkyl such as methyl or ethyl, or phenyl.
And aryl groups such as tolyl and tolyl. )
Secondary amines, RNH₂(In the formula, R is the same as above.
It ) Primary amines represented by), 2-methylimidazo
And imidazoles such as 2-phenylimidazole,
Alternatively, ammonia, tetramethylammonium boroha
Ilide, tetrabutylammonium borohydride
De, tetrabutylammonium phenylborate, tet
Salts such as lamethylammonium tetraphenylborate
Basic salts and the like can be mentioned.

These catalysts can be used alone or in combination of two or more, and the addition amount thereof is in the range of 10 ^-8 to 10 ^-3 mol with respect to 1 mol of the dihydric phenol as the main raw material. Is preferred. If the amount of the catalyst added is more than 10 ^-3 mol, problems such as coloring of the obtained polycarbonate may occur. When the amount of the catalyst used is less than 10 ^-8 mol, it takes a long time to complete the polymerization, which may lead to a decrease in productivity.

In the method of the present invention, an important point is to add an aromatic halogen compound or an aromatic nitro compound having an electron withdrawing group at the ortho or para position to the polymerization system.

As the aromatic halogen compound or aromatic nitro compound used in the present invention, compounds represented by the following general formula are preferably used.

[0024]

[Chemical 1] (In the formula (A), Q ¹ represents an electron-withdrawing group, and X ¹ , X ²
And X ³ represent a halogen atom, a nitro group or a hydrogen atom, and at least one of X ¹ , X ² and X ³ is a halogen atom or a nitro group. Further, in the formula (B), Q ² represents an electron-withdrawing group, and X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶
Represents a halogen atom, a nitro group or a hydrogen atom,
At least one of X ¹ , X ² , X ³ , X ⁴ , X ⁵ and X ⁶ is a halogen atom or a nitro group. ) Examples of the electron-withdrawing group Q ^{1 in} the formula (A) include a nitro group, a carbonyl-containing group and a cyano group. Of these, a cyano group is preferable. The electron-withdrawing group Q ^{2 in} formula (B)
Examples of include a carbonyl group, a sulfonyl group, and the like.

Suitable examples of the compound represented by the formula (A) include 2-chlorobenzonitrile, 2-fluorobenzonitrile, 2-nitrobenzonitrile, 4-chlorobenzonitrile, 4-fluorobenzonitrile and 4-fluorobenzonitrile. Nitrobenzonitrile, 4-chlorobenzonitrile, 4-fluorobenzonitrile, 4-nitrobenzonitrile,
2,4-dichlorobenzonitrile, 2,4-difluorobenzonitrile, 4-dinitrobenzonitrile, 2,6
-Dichlorobenzonitrile, 2,6-difluorobenzonitrile, 2,6-dinitrobenzonitrile and the like can be mentioned.

Preferred examples of the compound represented by the formula (B) include 2-chlorobenzophenone, 2-fluorobenzophenone, 2-nitrobenzophenone, 2-chlorodiphenyl sulfone, 2-fluorodiphenyl sulfone and 2-nitro. Examples thereof include diphenyl sulfone, 2,4-dichlorobenzophenone, 2,4-difluorobenzophenone, 2,4-dichlorodiphenyl sulfone and 2,4-difluorodiphenyl sulfone.

Among these, particularly preferable are 2-chlorobenzonitrile and 2-chlorobenzophenone.

The amount of these aromatic compounds added is preferably in the range of 10 ^-6 to 10 ^-2 mol per mol of the dihydric phenol. If the addition amount is less than 10 ^-6 mol, the expected effect is not sufficiently exerted, and if it exceeds 10 ^-2 mol, the production cost rises although it depends on the aromatic compound used.

These aromatic compounds may be added at the same time as the monomers from the beginning of the polymerization reaction, or may be added at any time during the polymerization reaction to achieve the intended purpose.
In the reaction system, these aromatic compounds react with the active end of the polymer to form a chemically stable ether bond,
It is considered that a basic active terminal is deactivated to obtain a polycarbonate having excellent hydrolysis resistance. Also,
Since the compound to be added is not an acidic substance, there is no problem in quality even if added in excess. As the reaction progresses, the growth rate of the main chain is expected to slow down, but the reaction between the active end of the polymer and the aromatic compound is relatively slow compared to the transesterification reaction, which is the growth reaction of the main chain. Since these compounds proceed slowly, even if these aromatic compounds are present in the system from the initial stage of polymerization, it is considered that the degree of inhibiting the polymerization reaction is small when the addition amount is small.

In the present invention, when a polycarbonate is produced, a polyfunctional compound having 3 or more functional groups in one molecule may be used in combination as a branching agent.

Examples of such polyfunctional compounds include phloroglucin, pyrogallol, 1,1,1-tris (4-hydroxyphenyl) methane, 1,1,1-tris (4-hydroxyphenyl) ethane, 1 , 1,1-
Tris (4-hydroxyphenyl) propane, 1,1,
1-tris (3-methyl-4-hydroxyphenyl) ethane, 4,6-dimethyl-2,4,6-tris (4-hydroxyphenyl) -2-heptene, 4,6-dimethyl-2,4,6 -Tris (4-hydroxyphenyl) heptane, 2,6-dimethyl-2,4,6-tris (4-hydroxyphenyl) -3-heptene, 1,3,5-tris (2-hydroxyphenyl) benzene, 1 , 3,5-
Tris (4-hydroxyphenyl) benzene, tris (4-hydroxyphenyl) -phenylmethane, 2,2
-Bis [4,4-bis (4-hydroxyphenyl) cyclohexyl] propane, 2,4-bis [α- (4-hydroxyphenyl) isopropyl] phenol, 2,6-
Bis (2'-hydroxy-5'-methylbenzyl) -4
-Methylphenol, 2- (4-hydroxyphenyl)
-2- (2,4-dihydroxyphenyl) propane,
α, α ′, α ″ -tris (4-hydroxyphenyl)-
1,3,5-triisopropylbenzene, α-methyl-
α, α ', α'-tris (4-hydroxyphenyl)-
1,4-diethylbenzene, hexakis [4- {α-
(4-Hydroxyphenyl) isopropyl} phenyl]
-O-terephthalic acid ester, tetrakis (4-hydroxyphenyl) methane, tetrakis [4- {α- (4-
Hydroxyphenyl) isopropyl} phenoxy] methane, 1,4-bis [(4 ', 4 "-dihydroxytriphenyl) methyl] benzene, 2,4-dihydroxybenzoic acid, trimellitic acid, trimesic acid, pyromellitic acid, cyanurate conversion , 3,3-bis (3-methyl-4-hydroxyphenyl) -2-oxo-2,3-dihydroindole, 3,3-bis (4-hydroxyaryl) oxindole, 5-chloroisatin, 5,7 -Dichloroisatin, 5-bromoisatin phloroglyside and the like.

The polymerization temperature of the polycarbonate in the present invention is not particularly limited, but is usually in the range of 100 ° C to 300 ° C, preferably 130 ° C to 280 ° C. If the temperature is lower than 100 ° C., the reaction progresses slowly, and if it exceeds 300 ° C., side reactions may occur, or the polycarbonate produced may deteriorate. More preferably, the temperature is gradually increased to 180 ° C. to 2 in accordance with the progress of the reaction.
A good way is to raise the temperature to 80 ° C.

The pressure during the reaction is set according to the vapor pressure of the monomer used and the reaction temperature. This is not limited as long as it is set so that the reaction can be carried out efficiently. Usually, in the initial stage of the reaction, 1 to 50 atm
In many cases, the atmospheric pressure or pressurized state up to (760 to 38000 torr) is set, and the pressure is reduced in the latter stage of the reaction, preferably 0.01 to 100 torr finally. The reaction time may be such that it reaches the target molecular weight, and is usually about 0.2 to 10 hours.

The reaction is preferably carried out in an atmosphere of an inert gas such as nitrogen or argon, and if necessary, a terminal stopper, an antioxidant or the like may be added or an inert solvent may be used. .

Examples of the terminal terminator are on-butylphenol, mn-butylphenol, pn-butylphenol, o-isobutylphenol, m-isobutylphenol, p-isobutylphenol, ot-butylphenol and mt. -Butylphenol, pt-butylphenol, on-pentylphenol, mn-
Pentylphenol, pn-pentylphenol, o
-N-hexylphenol, mn-hexylphenol, pn-hexylphenol, o-cyclohexylphenol, m-cyclohexylphenol, p-cyclohexylphenol, o-phenylphenol, m-
Phenylphenol, p-phenylphenol, on
-Nonylphenol, mn-nonylphenol, p-
n-nonylphenol, o-cumylphenol, m-cumylphenol, p-cumylphenol, o-naphthylphenol, m-naphthylphenol, p-naphthylphenol, 2,6-di-t-butylphenol, 2,6
-Di-t-butylphenol, 2,4-di-t-butylphenol, 3,5-di-t-butylphenol, 2,
5-dicumylphenol, 3,5-dicumylphenol, 1-benzyl-4- (hydroxybenzyl) benzene, dibenzyl-4- (4-hydroxybenzyl) benzene, and 2,2,4-trimethyl-4- ( 4-hydroxyphenyl) chroman, 2,4,4-trimethyl-
Examples include monohydric phenols such as chroman derivatives such as 4- (4-hydroxyphenyl) chroman.

Of these phenols, although not particularly limited in the present invention, pt-butylphenol and p-t-butylphenol
-Cumylphenol, p-phenylphenol and the like are preferred.

Further, a carbonic acid diester compound is optionally used as another end stopper. Specific examples of such a carbonic acid diester compound end-stopping agent include carbobutoxyphenylphenyl carbonate, methylphenylbutylphenyl carbonate, ethylphenylbutylphenyl carbonate, dibutyldiphenyl carbonate, biphenylylphenyl carbonate, dibiphenylyl carbonate, cumyl. Phenyl carbonate, dicumyl phenyl carbonate, naphthyl phenyl carbonate, dinaphthyl phenyl carbonate, carbopropoxyphenyl phenyl carbonate, carboheptoxyphenyl phenyl carbonate, carbomethoxy-t-butylphenyl phenyl carbonate, carbopropoxy phenylmethyl phenyl carbonate, chromanyl phenyl Carbonate, dichromanyl carbonate, etc. It is. The C _7-30 - alkyl carbonyloxy benzene, C _7-30 - fatty alcohols, phenyl (C _1-12 -
Examples thereof include alkoxy) benzoate, phenyldi (C _1-12 -alkoxy) benzoate, phenyl tri (C _1-12 -alkoxy) benzoate, and phenyl (C _1-12 -alkoxy) sulfonate.

The amount of the terminal stopper present is divalent phenol 1.
When it is in the range of 0.05 mol% to 10 mol% with respect to the mols, the hydroxyl group end of the obtained polycarbonate is blocked, so that a polycarbonate having sufficiently excellent heat resistance and water resistance can be obtained, and the polycondensation reaction This is preferable because it increases the speed. The total amount of the terminal terminator and carbonic acid diester may be added to the reaction system in advance, or a part thereof may be added to the reaction system in advance and the rest may be added as the reaction progresses. Further, in some cases, after the polycondensation reaction between the dihydric phenol and the carbonic acid diester partially proceeds, the whole amount may be added to the reaction system.

Antioxidants include tris (nonylphenyl) phosphite, trisphenylphosphite, and 2
Phosphorus antioxidants such as -ethylhexyl diphenyl phosphite, trimethyl phosphite, triethyl phosphite, tricresyl phosphite and triaryl phosphite are preferably used.

As the inert solvent, aromatic compounds such as diphenyl ether, halogenated diphenyl ether, diphenyl sulfone, benzophenone, polyphenyl ether, dichlorobenzene and methylnaphthalene, gases such as carbon dioxide, dinitrogen monoxide and nitrogen, and chlorofluorocarbon. Hydrocarbons, alkanes such as ethane and propane, cyclohexane, tricyclo (5,2,10) -decane, cycloalkanes such as cyclooctane and cyclododecane, alkenes such as ethylene and propene, and sulfur hexafluoride. Can be mentioned.

In addition to the polycarbonate obtained by the present invention, a plasticizer, a pigment, a lubricant, a release agent,
Well-known additives such as stabilizers and inorganic fillers can be blended and used.

Further, these polycarbonates can be blended with polymers such as polyolefin and polystyrene, and in particular, polyphenylene ether, polyether nitrile, and terminal-modified polysiloxane having OH group, COOH group, NH ₂ group and the like at the terminal. It is effective when used in combination with a compound, modified polypropylene, modified polystyrene or the like.

[0043]

The present invention will be described in more detail below with reference to examples of the present invention and comparative examples thereof, but the present invention is not limited to these examples.

Example 1 In a 500 ml separable flask equipped with a stirrer and a distillation device, 22.8 g (0.1 mol) of 2,2-bis (4-hydroxyphenyl) propane and 21.4 g (0. 1 mol) was administered. 0.4 mg (1 × 10 ⁻⁵ mol) of sodium hydroxide and 22 mg (1 × 10 ⁻⁴ mol) of 2-chlorobenzophenone were added thereto. Then, the mixture was stirred at 180 ° C. for 60 minutes under an argon stream, then the reaction temperature was raised to 240 ° C., and the reaction was performed while gradually reducing the pressure reduction degree to 50 mmHg. Finally, polymerization was performed under the conditions of 1 mmHg and 270 ° C. for 60 minutes, and the produced phenol was distilled off to obtain a polycarbonate. The glass transition point (Tg) of the product was 151 ° C. when measured by thermal analysis. In addition, a solution of 0.2 g / dl in methylene chloride as a solvent is at 20 ° C.
The reduced viscosity was 0.57, and the viscosity average molecular weight calculated from this value was 23,600. Further, the obtained polycarbonate was subjected to hot press molding under the conditions of 270 ° C. for 2 minutes to prepare a plate having a thickness of 3 mm.
This was exposed to 121 ° C. steam for 48 hours in an autoclave, and the change of the plate was visually observed.
The results are shown in Table 1.

Example 2 In Example 1, instead of 2-chlorobenzophenone, 4-chlorobenzophenone was used.
The same operation as in Example 1 was carried out except that chlorobenzonitrile was used to obtain a polycarbonate. The glass transition temperature (Tg), the molecular weight and the result of the steam exposure test of this product are shown in Table 1.

Example 3 In Example 1, 4-chlorobenzophenone was replaced by 4-
The same operation as in Example 1 was carried out except that nitrobenzophenone was used to obtain a polycarbonate. The glass transition temperature (Tg), the molecular weight and the result of the steam exposure test of this product are shown in Table 1.

Comparative Example 1 Polycarbonate was obtained in the same manner as in Example 1 except that 2-chlorobenzophenone was not used. The glass transition temperature (Tg), the molecular weight and the result of the steam exposure test of this product are shown in Table 1.

[0048]

[Table 1] In the examples and comparative examples, the glass transition temperature (T
g) was measured using a DSC at a temperature rising rate of 20 ° C./min, and the viscosity average molecular weight was [η] = 1.11 × 10 ⁻⁴ Mv.
^It was calculated from the measured reduced viscosity using the formula of ^0.82 .

[0049]

Industrial Applicability According to the present invention, it is possible to produce a polycarbonate having excellent heat resistance and hydrolysis resistance and excellent quality with high productivity.

Claims (1)

[Claims] 1. When producing a polycarbonate from a dihydric phenol and a carbonic acid diester by transesterification in the presence of an ester exchange catalyst, an aromatic halogen compound or an aromatic nitro compound having an electron-withdrawing group at the ortho or para position is polymerized. A method for producing a polycarbonate, which comprises adding to a system.