JPH05148354A - Production of polycarbonate - Google Patents

Abstract

PURPOSE:To obtain a colorless transparent high-molecular polycarbonate without using any phosgene by effecting the melt polycondensation of a dihydroxy compound with a carbonic ester in the presence of a specified transesterification catalyst. CONSTITUTION:1mol of a dihydroxy compound of any one of formulas I-IV (wherein R1 to R4 are each H 1-8C linear or branched alkyl or phenyl; X is halogen; (n) is 0-4; and (m) is 1-4) and 1.01-1.5mol of a carbonic diester are subjected to melt polycondensation at 100-300 deg.C in the presence of a transesterification catalyst comprising 10<-1> to 10<-5>mol, per mol of the, dihydroxy compound, of an electron-donating amine compound, 10<-2> to 10<-6>mol of an alkali (alkaline earth) metal compound and 10<-4> to 10<-6>mol of a phosphorus compound of any one of formulas V-IX (wherein R1 is a 1-30C hydrocarbon residue).

Description

Detailed Description of the Invention

[0001]

The present invention relates to a catalyst selected from an electron-donating amine compound and a catalyst selected from an alkali metal compound or an alkaline earth metal compound and a catalyst selected from a phosphorus compound. The present invention relates to a method for producing a polycarbonate, which comprises melt-polycondensing a divalent hydroxy compound and a carbonic acid diester by a transesterification method.

[0002]

BACKGROUND OF THE INVENTION The high molecular weight polycarbonates of the present invention are general purpose engineering thermoplastics having a wide variety of uses, especially for injection molding or as a glass sheet alternative to window glass.

In the transesterification reaction, a transesterification catalyst is added to dihydric phenol and carbonic acid diester,
A prepolymer was synthesized while distilling phenol under heating and reduced pressure, and finally, it was heated to 290 ° C. or higher under high vacuum to distill phenol to obtain a high molecular weight polycarbonate (US Pat. No. 4,345,062). ) However, unlike other engineering plastics, high-molecular-weight polycarbonate requires a high temperature of 290 ° C. or higher as a reaction condition because it has a very high melt viscosity, and a high vacuum is required for distilling phenol having a high boiling point. (1-1
Since it requires 0 ^-2 Torr), industrialization is difficult from the viewpoint of equipment, and it is known that the hue and physical properties of the polycarbonate produced are adversely affected.

[0004]

DISCLOSURE OF THE INVENTION The present inventors have selected a catalyst selected from an electron donating amine compound and a divalent hydroxy compound and a carbonic acid diester as a compound which forms a carbonate bond, and an alkali metal compound or an alkaline earth metal compound. It has been found that polycondensation in the presence of a catalyst selected from the above and a catalyst selected from phosphorus compounds gives high molecular weight polycarbonates without toxic phosgene and without any coloration.

In particular, the phosphorus compound used here is a very effective compound in that it not only contributes as a transesterification catalyst but also contributes greatly to the hue improvement.

The present invention relates to the following inventions 1) to 4). 1) Transesterification method of divalent hydroxy compound and carbonic acid diester in the presence of a catalyst selected from an electron-donating amine compound, a catalyst selected from an alkali metal compound or an alkaline earth metal compound, and a catalyst selected from a phosphorus compound A method for producing a polycarbonate, characterized in that it is melt-polycondensed by 2) A method for producing a polycarbonate, wherein the phosphorus compound described in 1) is a combination of at least two or three or more selected from compounds represented by Chemical formulas 1, 2, 3, 4, and 5. 3) 2
The method for producing a polycarbonate according to 1) or 2), wherein the valent hydroxy compound is a compound represented by Chemical Formulas 6, 7, 8, and 9.
4) The method for producing the copolycarbonate according to 1) or 2), which comprises two or more selected from the divalent hydroxy compounds described in 3).

Typical examples of the electron-donating amine compound that can be used in the present invention include 4-dimethylaminopyridine and 4
-Diethylaminopyridine, 4-pyrrolidinopyridine,
4-aminopyridine, 2-hydroxypyridine, 4-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 2-methoxyimidazole, 1-methylimidazole, aminoquinoline, 4-methylimidazole, diazabicyclooctane (DABCO) Etc.

Representative examples of alkali metal compounds and alkaline earth metal compounds are sodium hydroxide, lithium hydroxide, potassium hydroxide, sodium hydrogen carbonate, lithium hydrogen carbonate, potassium hydrogen carbonate, sodium carbonate, lithium carbonate, potassium carbonate. , Sodium acetate, lithium acetate, potassium acetate, sodium stearate, lithium stearate, potassium stearate, sodium borohydride, lithium borohydride, potassium borohydride, sodium benzoate, lithium benzoate, potassium benzoate, water Barium oxide, calcium hydroxide, magnesium hydroxide, barium hydrogen carbonate, calcium hydrogen carbonate, magnesium hydrogen carbonate, barium carbonate, calcium carbonate, magnesium carbonate, barium acetate, calcium acetate, magnesium acetate , Barium stearate, calcium stearate, magnesium stearate and the like.

In the phosphorus compound, tetrakis (2,4-ditertbutylphenyl) -4,4'-biphenylene-di-phosphonite is a typical example of Chemical formula 1, and octadecyl-3- (is a typical example of Chemical formula 2. 3,5'-ge t
ert butyl-4-hydroxyphenyl) propionate. Further, it is also preferable to use the compounds represented by Chemical formula 3, Chemical formula 4, and Chemical formula 5.

As a typical example of carbonic acid diester,
Diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, diethyl carbonate, dimethyl carbonate, dibutyl carbonate,
Dicyclohexyl carbonate or the like is used. Of these, diphenyl carbonate is particularly preferable.

Typical examples of the divalent hydroxy compound include the following compounds. As bisphenols classified into Chemical formula 6, 2,2-bis- (4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxyphenyl) -4-methylpentane, 2,2-bis- (4
-Hydroxyphenyl) octane, 4,4'-dihydroxy-2,2,2-triphenylethane, 2,2-bis- (3,5-dibromo-4-hydroxyphenyl) propane and the like.

As bisphenol classified into Chemical formula 7,
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-bis- (4-hydroxy-3-tert.butylphenyl) propane and the like.

As bisphenol classified into Chemical formula 8,
1,1'-bis- (4-hydroxyphenyl) -p-diisopropylbenzene, 1,1'-bis- (4-hydroxyphenyl) -m-diisopropylbenzene and the like can be mentioned.

As bisphenol classified into Chemical formula 9,
1,1′-bis- (4-hydroxyphenyl) cyclohexane and the like can be mentioned. Furthermore, it is also possible to produce a copolycarbonate in which two or more divalent hydroxy compounds selected from Chemical Formulas 6, 7, 8, and 9 are combined.

The process of the present invention employs a catalyst selected from electron donating amine compounds and a catalyst selected from alkali metal compounds or alkaline earth metal compounds and a catalyst selected from phosphorus compounds such as bisphenol A. It is carried out by melt polycondensation of a divalent hydroxy compound with a carbonic acid diester.

The temperature at which this reaction proceeds is from 100 ° C to about 30 ° C.
The range is up to 0 ° C. Preferably 130 ° C to 280 ° C
The range is. If it is lower than 130 ° C, the reaction rate becomes slow, and if it exceeds 280 ° C, side reactions are likely to occur.

The electron-donating amine compound used as a catalyst requires 10 ^-1 to 10 ^-5 mol, preferably 10 ^-2 mol, per 1 mol of the divalent hydroxy compound present in the reaction system. It is 10 ^-4 mol. If it is less than 10 ^-5 mol, the catalytic action is small and the polymerization rate of the polycarbonate is slowed. If it is 10 ^-1 mol or more, the rate of remaining in the polycarbonate produced is high, which causes deterioration of the physical properties of the polycarbonate.

Further, the alkali metal compound and the alkaline earth metal compound used as the combined catalyst require 10 ^-2 to 10 ^-6 mol per mol of the divalent hydroxy compound present in the reaction system, but are preferable. Is 10 ⁻³ mol to 10 ⁻⁵ mol. If it is less than 10 ^-6 mol, the catalytic action is small and the polymerization rate of the polycarbonate becomes slower.
^If it is more than ^-2 mol, the residual rate in the produced polycarbonate becomes high, which causes deterioration of the physical properties of the polycarbonate.

Further, the phosphorus compound used as the combined catalyst needs to be 10 ⁻⁴ to 10 ⁻⁶ mol, preferably 10 ⁻³ mol, relative to 1 mol of the divalent hydroxy compound present in the reaction system. It is 10 ^-5 mol.

Further, the required amount of carbonic acid diester is required to be equimolar to the divalent hydroxy compound present in the reaction system.
Generally, in order to produce high molecular weight polycarbonate,
1 mol of the carbonate compound and 1 mol of the divalent hydroxy compound must react. With diphenyl carbonate, 2 mol of phenol are produced by the reaction. These 2 moles of phenol are distilled out of the reaction system.

However, the carbonic acid diester used is 1.01-1.1 with respect to 1 mol of the divalent hydroxy compound.
It is desired to be used in an amount of 5 mol, preferably 1.015 to 1.05 mol.

The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0023]

Example 1 2,2-bis (4-hydroxyphenyl)
Propane 22.8 g (0.1 mol), diphenyl carbonate 21.9 g (0.1025 mol) and 4-dimethylaminopyridine 0.024 g (2 × 10 ⁻⁴ mol), potassium acetate 0.098 mg (1 × 10 ^{− 6} mol) and 0.01 g (1 × 10 ⁻⁵ mol) of the phosphorus compound represented by Chemical formula ⁵ were placed in a Hastelloy separable flask, and the temperature was 180 ° C.
Melt and stir well, gradually raise the temperature while reducing the pressure,
Finally, the temperature was raised to 0.1 Torr and 270 ° C., and the produced phenol was distilled off to obtain a colorless and transparent polycarbonate. The viscosity average molecular weight (M
When v) was measured, it was Mv = 29,000. As a method for measuring the viscosity average molecular weight, the intrinsic viscosity [η] of the methylene chloride solution at 20 ° C. was measured using an Ubbelohde viscometer, and the viscosity average molecular weight (Mv) was calculated using the following formula. [Η] = 1.11 × 10 ⁻⁴ (Mv) ^{0.82 Further} , the glass transition temperature was 150 ° C.

[0024]

EXAMPLE 2 Under exactly the same conditions as in Example 1, 0.016 g (2 × 10 ⁻³ mol) of 2-methylimidazole instead of 4-dimethylaminopyridine, and 0.01 g of calcium carbonate instead of potassium acetate ( 1 × 10 ⁻⁴ mol), and 0.005 g (8 × 10 ⁻⁶ mol) of the phosphorus compound represented by Chemical formula 4 was used in place of the phosphorus compound represented by Chemical formula 5 in the same manner as in Example 1. A condensation reaction was performed to obtain a colorless transparent polycarbonate. The viscosity average molecular weight was 28,000 and the glass transition temperature was 149 ° C.

[0025]

Example 3 2,2-bis (4-hydroxyphenyl)
Propane 11.4 g (0.05 mol), 2,2-bis (4-hydroxy-3-tertbutylphenyl) propane 17.0 g (0.05 mol), diphenyl carbonate 22.5 g (0.105 mol) 4-dimethylaminopyridine 0.0024 g (2 × 10 ⁻⁵ mol), potassium acetate 0.098 mg (1 × 10 ⁻⁶ mol) and 0.01 g (1 × 10 ⁻⁵ mol) of the phosphorus compound represented by Chemical formula ⁵ Was melted under nitrogen and stirred to carry out a polycondensation reaction in the same manner as in Example 1 to obtain a colorless transparent polycarbonate. The viscosity average molecular weight is 25,500 and the glass transition temperature is 12
It was 8 ° C.

[0026]

Comparative Example 1 2,2-bis (4-hydroxyphenyl)
Propane 22.8 g (0.1 mol), diphenyl carbonate 22.0 g (0.1025 mol) and iron chloride (3
Value) into a flask and melt at 180 ° C. under nitrogen,
When thoroughly stirred and reacted in the same manner as in Example 1, the viscosity average molecular weight of the obtained polycarbonate was 2,
000, and was red.

[0027]

By using the catalyst selected from the electron-donating amine compound and the catalyst selected from the alkali metal compound or the alkaline earth metal compound and the catalyst selected from the phosphorus compound, toxic phosgene is not used. As a result, it was possible to obtain a colorless and transparent polycarbonate having a high molecular weight and containing no chlorine.

Claims (4)

[Claims] 1. A divalent hydroxy compound and a carbonic acid diester in the presence of a catalyst selected from an electron-donating amine compound and a catalyst selected from an alkali metal compound or an alkaline earth metal compound and a catalyst selected from a phosphorus compound. A method for producing a polycarbonate, which comprises melt-polycondensing by a transesterification method. 2. The phosphorus compound according to claim 1 is
A method for producing a polycarbonate, which comprises a combination of at least two or three or more selected from the compounds represented by 2, 3, 4, and 5. [Chemical 1] [Chemical 2] [Chemical 3] [Chemical 4] [Chemical 5] (R ₁ represents a hydrocarbon group having 1 to 30 carbon atoms.) 3. A divalent hydroxy compound is represented by chemical formula 6,7,8,9.
The method for producing a polycarbonate according to claim 1, which is represented by: [Chemical 6] [Chemical 7] [Chemical 8] [Chemical 9] (R ₁ , R ₂ , R ₃ , and R ₄ are hydrogen or have 1 to 8 carbon atoms.
Represents a straight chain or branched alkyl group or phenyl group, X represents a halogen atom, and n = 0 to 4, m =
1 to 4. ) 4. The method according to claim 1, wherein two or more selected from the divalent hydroxy compound according to claim 3 are used.
A method for producing the described copolycarbonate.