JP3096322B2 - Method for producing polycarbonate - Google Patents

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 a colorless high molecular weight polycarbonate from a dihydric phenol and a carbonic acid diester by a transesterification method.

[0002]

2. Description of the Related Art Polycarbonate is prepared by adding a solvent such as methylene chloride to an aqueous solution or suspension of a sodium salt of dihydric phenol and blowing phosgene into the phosgene method (interface polycondensation). It is produced by a transesterification method in which a dihydric phenol and a carbonic acid diester such as diphenyl carbonate are heated and melted, and polycondensed by a transesterification reaction under high temperature and reduced pressure.

[0003] Among these polycarbonate production methods, the interfacial polycondensation method is generally widely used. However, this method not only requires the use of extremely toxic phosgene, but also leaves chloride ions in the produced polycarbonate. If chlorine ions remain in the polycarbonate, the polymer is colored by molding at a high temperature. Therefore, it is necessary to wash the obtained polymer in order to reduce the concentration of residual chloride ions.

[0004] On the other hand, the transesterification method has such advantages that no highly toxic phosgene is required and that a step of removing residual chloride ions is not required. However, in the transesterification method, unlike the interfacial polycondensation method, it is generally difficult to obtain a high molecular weight polycarbonate. Furthermore, in the transesterification method, the reaction is carried out under high temperature and reduced pressure in the presence of a catalyst, so that the polymer is colored [Encyclopedia of Polymer Science and Engineering (Encyclopedia of Polymer Science and Engineering).
Engineering, 11, 651 (1988)].

[0005] In order to produce a polycarbonate having a low degree of coloration, a highly active transesterification catalyst is used as a catalyst for the production of Japanese Patent Publication No.
JP-A-14742 and JP-A-2-124934 propose a catalyst system in which a quaternary ammonium salt such as ammonium hydroxide is combined with an alkali metal or alkaline earth metal compound.

However, when an alkali metal compound is used,
It is known that an insoluble matter such as methylene chloride is formed in a polymer depending on reaction conditions [Encyclopedia of Polymer Science and
Technology (Encyclopedia of Polymer Science and T
echnology, 10, 722 (1969))]. Therefore, an alkali metal compound or an alkaline earth metal compound cannot be said to be an optimal catalyst for producing a high molecular weight polymer carbonate soluble in methylene chloride or the like.

Accordingly, an object of the present invention is to provide a method capable of producing a high-molecular-weight polycarbonate which is free of coloring and is soluble in a solvent such as methylene chloride by a transesterification reaction.

[0008]

The present inventors have achieved the above object by attaining
As a result of intensive studies, they have found that a high-molecular-weight polycarbonate which is hardly colored and which is soluble in a solvent can be obtained by using a compound consisting of a specific combination as a catalyst, thereby completing the present invention. That is, the present invention is a method for producing a polycarbonate from a dihydric phenol and a carbonic acid diester by a transesterification method, wherein an electron-donating amine compound and an acetic acid acetate are used as a catalyst.
Timon, bismuth acetate, stannous acetate, lead acetate and potassium acetate
Even without least selected from cadmium to provide a method for manufacturing a polycarbonate using the kind of compound.

Examples of the dihydric phenol include bis (4-hydroxyphenyl) methane and 1,1-bis (4
-Hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, , 2-bis (4
-Hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 4,4'-dihydroxy-2,2,2-triphenylethane, 2,2-bis (3
-Bromo-4-hydroxyphenyl) propane, 2,2
-Bis (3,5-dibromo-4-hydroxyphenyl)
Propane, 1,1-bis- (4-hydroxy-3-methylphenyl) propane, 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, 2,2-bis (4
-Hydroxy-3-t-butylphenyl) propane,
Bis (hydroxyaryl) alkanes such as 1,1-bis (4-hydroxy-3-t-butylphenyl) propane; 1,1′-bis (4-hydroxyphenyl) -p
-Diisopropylbenzene, 1,1'-bis (4-hydroxyphenyl) -p-diethylbenzene, 1,1'-
Bis (hydroxyaryl) arenes such as bis (4-hydroxyphenyl) -m-diisopropylbenzene; 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4-hydroxyphenyl) cyclohexane, , 1-bis (4-hydroxyphenyl)
Bis (hydroxyaryl) cycloalkanes such as cyclooctane; dihydroxydiaryl ethers such as 4,4'-dihydroxydiphenyl ether and 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether; 4,4'-dihydroxydiphenyl sulfide ,
Dihydroxydiaryl sulfides such as 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide; 4,4'-dihydroxydiphenyl sulphoxide;
Dihydroxydiarylsulfoxides such as 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfoxide;4,4'-dihydroxydiphenylsulfone;
And dihydroxydiarylsulfones such as 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone. Of these dihydric phenols,
2-bis (4-hydroxyphenyl) propane is commonly used. These dihydric phenols can be used alone or in combination of two or more.

Examples of the carbonic diester include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, dicyclohexyl carbonate, dimethyl carbonate, diethyl carbonate, dibutyl carbonate and the like. Among these carbonic acid diesters, diphenyl carbonate is frequently used. These carbonic acid diesters can be used alone or in combination of two or more.

The amount of the carbonic acid diester used is usually from 0.90 mol to 1.50 mol per 1 mol of the dihydric phenol.
Preferably it is about 0.95 to 1.25 mol.

If necessary, a dicarboxylic acid or a dicarboxylic acid ester may be used instead of a part of the carbonic acid diester. In this case, a polyester carbonate is obtained. As dicarboxylic acids and dicarboxylic esters, for example, terephthalic acid, diphenyl terephthalate,
Isophthalic acid, diphenyl isophthalate and the like. 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 type of the amine compound is not particularly limited as long as it has an electron donating property. Examples of the electron donating amine compound include pyridine, 4-aminopyridine, 2-aminopyridine, 4-dimethylaminopyridine, 4-diethylaminopyridine, 4-pyrrolidinopyridine, 2-hydroxypyridine, 4-hydroxypyridine, -Methoxypyridine, 4-methoxypyridine, picoline, pyrimidine, imidazole, 2-methylimidazole, 4-methylimidazole, 2-dimethylaminoimidazole, 2-methoxyimidazole, 2-mercaptoimidazole, pyrazole, aminoquinoline, benzimidazole, N , N-dimethylaniline, pyrrolidine, morpholine, N-methylmorpholine, piperidine,
Piperazine, 1,4-diazabicyclo [2.2.2] octane (DABCO), 1,8-diazabicyclo [5.
4.0] -7-undecene (DBU), 1,5-diazabicyclo [4.3.0] -5-nonene (DBN) and the like. These electron donating amine compounds can be used alone or in combination of two or more.

Compounds constituting the catalyst system together with the electron-donating amine compound include antimony acetate and bismuth acetate.
Selected from copper, stannous acetate, lead acetate and cadmium acetate.
At least one compound. These compounds
And a compound containing an element selected from Group IIb, Group IVb and Group Vb of the Periodic Table of the Elements . Compounds containing these elements may be either organic or inorganic compounds.

Elements belonging to Group IIb of the periodic table include zinc and cadmium. Preferred Group IIb elements include zinc and cadmium.

Examples of the zinc compound include zinc acetate,
Zinc oxalate, zinc chloride, zinc sulfate, zinc nitrate, zinc carbonate, zinc oxide, zinc hydroxide, zinc stearate, zinc-
Chromium oxide, zinc-chromium-copper oxide and the like can be mentioned.

[0017] As cadmium compound, for example, push from <br/> c cadmium, cadmium oxide, and stearic acid cadmium.

The elements belonging to Group IVb include silicon,
Examples include germanium, tin, and lead. Preferred Group IVb elements include tin and lead.

Examples of the silicon compound include silicon oxide, silicon-aluminum oxide (SiO ₂ —Al ₂ O ₃ ), and silicon-magnesium oxide (SiO ₂ —MgO). Examples of the germanium compound include oxides Examples include germanium and germanium hydroxide.

[0020] As the tin compound, organic or inorganic compounds containing tin, for example, shea oxalic acid stannous octylate, stannous chloride, stannic chloride, stannous oxide, stannic oxide, And tetraphenyltin.

[0021] Representative examples of lead compounds are, for example, boric lead, lead citrate, lead hydroxide, lead oxide, lead phosphate, lead phthalate and lead stearate and the like.

The elements belonging to the Vb group include antimony and bismuth. The antimony compound, for example, shea oxalic acid antimony, triphenyl antimony, antimony trioxide, antimony pentoxide, triphenoxy antimony, trimethoxy antimony, triethoxy antimony, three and antimony chloride.

[0023] As bismuth compounds, organic or inorganic compound containing bismuth, e.g., shea Yuusan bismuth, triphenyl bismuth, bismuth trioxide, and the like bismuth trichloride.

In the method of the present invention, an electron-donating amine compound, antimony acetate, bismuth acetate, stannous acetate, vinegar
A catalyst system is formed by combining one or more compounds selected from lead acid and cadmium acetate , and a polyhydric phenol is subjected to a melt polycondensation reaction with a carbonic acid diester. Acetic acid
Nchimon, bismuth acetate, stannous acetate, lead acetate and acetic acid
Selected of Gobutsu cadmium may constitute a catalyst system in combination solely with the electron-donating amine compound,
Wherein the multiple compounds electron donating amine compound and may constitute a catalyst system in combination.

The amount of the electron-donating amine compound may be a not jeopardized the polycondensation reaction, for example, for the dihydric phenol, ^10-7 to ^10-1 mol, preferably 10
It is about ^-6 to 10 ^-2 mol. When the use amount of the electron-donating amine compound is less than 10 ^-7 mol, under a high temperature of about 220 ° C to 300 ° C in order to obtain a desired degree of polymerization, for example, a viscosity average molecular weight of about 5,000 to 50,000. , It is necessary to polymerize for a long time, and the polycarbonate is easily colored by a side reaction. When the amount exceeds 10 ^-1 mol, the amount of the catalyst remaining in the produced polycarbonate increases.
The physical properties of the polycarbonate are likely to decrease.

Further, antimony acetate, bismuth acetate,
Stannous acetate, selected from lead acetate and cadmium acetate
The amount of the reduction compound, for example, 1 for the dihydric phenol
It is about 0 ^-8 to 10 ^-2 mol, preferably about 10 ^-7 to 10 ^-3 mol. When the use amount of these compounds is less than 10 ^-8 , it takes a long time to obtain a polycarbonate having a desired degree of polymerization, and coloring is easily caused by a side reaction. On the other hand, if it exceeds 10 ^-2 mol, coloring and physical properties are liable to be caused by side reactions.

The transesterification is carried out by a conventional method employed in the melt polycondensation reaction, for example, 80 to 250 at the beginning of the reaction.
C., preferably at about 100-230 ° C.,
The reaction can be carried out by raising the temperature while reducing the pressure and finally causing the reaction to take place at about 250 to 320 ° C. The degree of pressure reduction at the end of the reaction is preferably, for example, 0.3 Torr or less.

In such a transesterification reaction,
The polycondensation reaction proceeds smoothly, and a high molecular weight polycarbonate is obtained. Moreover, the obtained polycarbonate is
It is soluble in halogenated hydrocarbons such as methylene chloride, chloroform and chlorobenzene, and does not generate insolubles.

[0029]

According to the method of the present invention, the transesterification reaction between dihydric phenol and carbonic acid diester is carried out in the presence of a specific catalyst. A soluble high molecular weight polycarbonate is obtained.

[0030]

EXAMPLES The present invention will be described below in more detail with reference to Examples, but the present invention is not limited to these Examples.

The viscosity average molecular weight was calculated from the intrinsic viscosity [η] of a methylene chloride solution of the polymer at 20 ° C. according to the following equation.

[Η] = 1.11 × 10 ⁻⁴ Mv ^0.82 (Mv
Indicates a viscosity average molecular weight) Further, a molecular weight distribution Mw / Mn (Mw is a weight average molecular weight,
Mn indicates the number average molecular weight) is 0.5
It was determined by a usual gel permeation chromatography method using a weight% chloroform solution.

Example 1 2,2-bis (4-hydroxyphenyl) propane 4
5.6 g (0.2 mol) and diphenyl carbonate 4
To 2.8 g (0.2 mol) were added 1.2 × 10 ⁻³ g (1 × 10 ⁻⁵ mol) of N, N-dimethyl-4-aminopyridine and 7.6 × 10 ⁻⁴ g of lead acetate (2 mol). × 10 ^-6 mol). After the atmosphere in the reaction system was replaced with nitrogen, the temperature was raised while gradually reducing the pressure, phenol produced by the reaction was distilled off, and finally a polycondensation reaction was performed at 0.1 Torr and 270 ° C. for 1.5 hours.

The obtained polycarbonate was colorless and transparent. Also, the viscosity average molecular weight Mv of the polycarbonate
38,100, molecular weight distribution Mw / Mn = 3.00, and glass transition temperature was 150 ° C.

EXAMPLE 2 6.0 × 10 ^-4 g of antimony acetate (2 ×
10 ^-6 mol), and the temperature was raised under reduced pressure in the same manner as in Example 1, and finally a polycondensation reaction was performed at 0.1 Torr and 270 ° C. for 2 hours.

The obtained polycarbonate was colorless and transparent. Further, the viscosity average molecular weight Mv of the polycarbonate is 3
9,400, molecular weight distribution Mw / Mn = 2.75, and glass transition temperature was 150 ° C.

Example 3 4.7 × 10 ^-4 g (2 × 10 ^-4 g) of stannous acetate instead of lead acetate
^-6 mol), and the temperature was raised while reducing the pressure in the same manner as in Example 1;
The polycondensation reaction was performed for 5 hours.

The obtained polycarbonate was colorless and transparent. Also, the viscosity average molecular weight Mv of the polycarbonate
37,000, molecular weight distribution Mw / Mn = 2.75, glass transition temperature was 150 ° C.

Example 4 In place of lead acetate, 7.6 × 10 ⁻⁴ g of bismuth acetate (2 ×
10 ^-6 mol), and the temperature was raised under reduced pressure in the same manner as in Example 1, and finally a polycondensation reaction was performed at 0.1 Torr and 270 ° C. for 1.5 hours.

The obtained polycarbonate was colorless and transparent. Also, the viscosity average molecular weight Mv of the polycarbonate
39,800, molecular weight distribution Mw / Mn = 2.95, and glass transition temperature were 150 ° C.

Example 5 In place of lead acetate, 5.2 × 10 ^-4 g of cadmium acetate (2
The temperature was raised under reduced pressure in the same manner as in Example 1 except that (× 10 ⁻⁶ mol) was used, and finally a polycondensation reaction was performed at 0.1 Torr and 270 ° C. for 1.5 hours.

The obtained polycarbonate was colorless and transparent. Further, polycarbonate has a viscosity average molecular weight Mv =
31,500, molecular weight distribution Mw / Mn = 2.75, glass transition temperature was 150 ° C. Comparative Example 1 N, N-dimethyl-4-aminopyridine 1.2 × 10 ⁻⁴ without adding lead acetate Except for adding g (2 × 10 ⁻⁵ mol), the temperature was raised under reduced pressure in the same manner as in Example 1, and finally a polycondensation reaction was performed at 0.1 Torr and 270 ° C. for 2 hours.

Although the obtained polycarbonate was colorless and transparent, the viscosity average molecular weight was Mv = 8,000, the molecular weight distribution was Mw / Mn = 2.65, and the polycarbonate was low in molecular weight.

Comparative Example 2 6.0 × 10 ⁻⁴ g of antimony acetate (2 × 10 ^4
-6 mol), the temperature was raised under reduced pressure in the same manner as in Example 1, and finally a polycondensation reaction was performed at 0.1 Torr and 270 ° C. for 2 hours.

The obtained polycarbonate was colorless and transparent, but had a viscosity average molecular weight Mv = 9,500, a molecular weight distribution Mw / Mn = 2.70, and a low molecular weight.

Comparative Example 3 Potassium acetate 2.0 × 10 ⁻⁴ g (2 × 1
0 ^-6 mol), and the temperature was raised while reducing the pressure in the same manner as in Example 1;
A time polycondensation reaction was performed.

The obtained polycarbonate was colored yellow and was partially insoluble in methylene chloride. In addition, polycarbonate soluble in methylene chloride is
Viscosity average molecular weight Mv = 42,000, molecular weight distribution Mw /
Mn was 4.5 and the molecular weight distribution was broad.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-26722 (JP, A) JP-A-2-251524 (JP, A) JP-B-36-694 (JP, B1) Mikio Matsugane, Shogo Tahara , Kato Shuji, "Plastic Materials Course 5 Polycarbonate Resin", Nikkan Kogyo Shimbun, September 30, 1969, p. 63 (58) Field surveyed (Int.Cl. ⁷ , DB name) C08G 64/00-64/42

Claims (1)

(57) [Claims] 1. A method for producing a polycarbonate from a dihydric phenol and a carbonic acid diester by a transesterification method, wherein an electron-donating amine compound and vinegar are used as a catalyst.
Antimony acid, bismuth acetate, stannous acetate, lead acetate and
Polycarbonate production method using a one compound even without least selected from cadmium acetate.