JPH03140324A - Production of polycarbonate - Google Patents

Abstract

PURPOSE:To obtain the subject colorless and transparent product having high molecular weight and free from chlorine ion without using toxic phosgene by carrying out melt-polycondensation of a dihydric hydroxy compound and a bisaryl carbonate in the presence of an electron-donative amine compound catalyst. CONSTITUTION:The objective polycarbonate can be produced by the melt- polycondensation of (A) a dihydric hydroxy compound [e.g. the dihydric phenol of formula I to IV (R1 to R4 are H, 1-8C alkyl or phenyl; X is halogen; n is 0 4; m is 1-4) and (B) a bisaryl carbonate in the presence of (C) a catalyst selected from salts of electron-donative amine compounds (e.g. N,N-dimethyl-4- aminopyridine or diazabicyclooctane).

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention provides a method for producing electron-donating amine compounds in the presence of a salt catalyst.
The present invention relates to a method for producing a high molecular weight polycarbonate obtained by melt polycondensation of a hydroxyl compound and a bisaryl carbonate.

PRIOR ART AND PROBLEMS TO BE SOLVED BY THE INVENTION The high molecular weight polycarbonates of the present invention have a wide range of uses, particularly for injection molding or as glass sheets in place of window panes. It is a general-purpose engineering thermoplastic. Although the interfacial polycondensation method is generally effective for producing polycarbonate, it has drawbacks such as the use of toxic phosgene and the fact that chlorine ions remain in the polycarbonate produced. In order to eliminate these drawbacks, it was proposed in 1983 that polycarbonate could be produced by an interfacial polycondensation reaction between liquid trichloromethyl chloroformate, which is a dimer of phosgene, and a special dihydric phenol instead of toxic phosgene. -182336.

However, there is only a description of 9,9-bis(4-hydroxyphenyl)fluorenes, which are special dihydric phenols. Also, obtaining polycarbonate from 2,2-bis(4-hydroxyphenyl)propane using triphosgene instead of the toxic phosgene has been reported by Angew, Chem, (Angevante, Hemi-).
Heaven.

922 (1987), a reaction mechanism in which phosgene is generated has also been proposed.

(Means for Solving the Problems) The present inventors used bisaryl carbonate and a divalent hydroxy compound as a compound that generates a carbonate bond in the presence of a salt of an electron-donating amine compound (excluding chloride salts). It has been discovered that a high molecular weight polycarbonate which does not use toxic phosgene and is essentially free of chlorine ions can be obtained by melt polycondensation.

The present invention provides (1) a method for producing polycarbonate, which comprises melt polycondensing a divalent hydroxy compound and bisaryl carbonate in the presence of a catalyst selected from salts of electron-donating amine compounds.

(2) The divalent hydroxy compound has the general formula (I), (II)
), (III).

A method for producing the polycarbonate described in (1) above, which is represented by (IV).

(R1, R2, R3, R4 are hydrogen, a linear or branched alkyl group having 1 to 8 carbon atoms, or a phenyl group; X is a halogen atom; n=0 to 4; m=1 to 4) It is related to. (3) A method for producing the polycarbonate copolymer described in (1) or (2) above.

Representative examples of electron-donating amine compounds that can be used in the present invention include N,N-dimethyl-4-aminopyridine 4-diethylaminopyridine 4-pyrrolidinopyridine, 4-(
5-noryl)-pyridine, 4-aminopyridine.

2-aminopyridine 2-hydroxypyridine 2-methoxypyridine, 4-methoxypyridine, 4-hydroxypyridine, 2-dimethylaminoimidazole, 2-methoxyimidazole, 2-mercaptoimidazole, 2
-Aminopyridine Aminoquinoline Imidazole 2-
Examples include methylimidazole 4-methylimidazole diazabicyclooctane (DABCO) and the like.

Furthermore, 2.1 (,'
A typical example of an acid that forms a carbonate is vinegar.

These include formic acid, nitric acid, nitrous acid, oxalic acid, sulfuric acid, phosphoric acid, fluoroboric acid, and hydrogenboronic acid.

Moreover, the following compounds are mentioned as typical examples of divalent hydroxy compounds. - Divalent hydroxy compounds classified into formula (I) include 2,2-bis-(4-hydroxyphenyl)propane, 2,2-bis-(4-hydroxyphenyl)butane, 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 divalent hydroxy compounds classified as sterilization (II), 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-tert-butylphenyl) ) Examples include propane. - As divalent hydroxy compounds classified as sterilization (III), 1.1'-bis-(4-hydroxyphenyl)-p-diisopropylbenzene, 1.1'-
Examples include bis-(4-hydroxyphenyl)-m-diisopropylbenzene. - 1,1-bis-(4-hydroxyphenyl)cyclohexane is an example of bisphenol classified as sterilizing (IV). Furthermore, it is also possible to produce a copolymerized polycarbonate in which two or more dihydric phenols selected from (I), (II), (III), and (IV) are combined.

The process of the invention is carried out by melt polycondensation reaction of a divalent hydroxy compound such as bisphenol A with bisphenyl carbonate using a catalyst selected from salts of electron-donating amine compounds. .

The temperature at which this reaction proceeds is from 100'C or higher to approximately 300°C.
The range is up to C. Preferably from 130°C to 280°C
°C range. If the temperature is less than 130°C, the reaction rate will be slow, and if it exceeds 280°C, side reactions will likely occur.

The salt of the electron-donating amine compound used as a catalyst is required in an amount of 10-1 to 10-5 mol, preferably 10-2 to 10-4 mol, based on the dihydric phenol present in the reaction system. It is. If the amount is less than 10.5 mol, the catalytic effect will be low and the polymerization rate of the polycarbonate will be slow; if it is more than 10@-1 mol, the proportion remaining as a catalyst in the polycarbonate produced will be high, leading to a decrease in the physical properties of the polycarbonate.

Further, the required amount of bisaryl carbonate is equivalent to the mole of the divalent hydroxy compound present in the reaction system. Generally, in order to produce a high molecular weight polycarbonate, 1 mole of a carbonate compound and 1 mole of a divalent hydroxy compound must react. Bisaryl carbonate 1・
When using 2 moles of hydroxy compound are produced by the reaction. These 2 moles of hydroxy compound are distilled out of the reaction system.

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

(Example) Example 1 2.2-bis(4-hydroxyphenyl)propane 22
．． 8 g (0.1 mol), 0.288 g (2X 10-'' mol) of 2-methylimidazole carbonate, and 21.4 g (0.1 mol) of bisphenyl carbonate were added under nitrogen.
After accumulating at 180°C for 1 hour, the temperature was gradually increased while reducing the pressure, and finally 0.1 TO'' was produced by polycondensation reaction at 270°C for 1 hour, and the phenol was distilled off.
A colorless and transparent polycarbonate was obtained. The viscosity average molecular weight was measured and found to be Mv=27,000. Further, the glass transition temperature was 150°C.

The viscosity average molecular weight was measured by measuring the intrinsic viscosity [rll of a methylene chloride solution at 20°C using an Ubbelohde viscometer, and calculating the viscosity average molecular weight Mv using the following formula.

[rll=1.11 moi 0-4 (Mv) 0.82 Example 2 Under exactly the same conditions as in Example 1, 0.0184 g of carbonate of 4-dimethylaminopyridine was added instead of carbonate of 2-methylimidazole. (IX 10' mol) was added, and after accumulating for 2 hours under nitrogen, a polycondensation reaction was carried out in the same manner as in Example 1 to obtain a colorless and transparent polycarbonate. Measuring the viscosity average molecular weight! vl v = 28,000. Further, the glass transition temperature was 150°C.

Example 3 2,2-bis(4-hydroxyphenyl)propane 11
．． 4g (50 mol%), 2.2-bis(4-hydroxy-3-tert-butylphenyl)propane 17.0g
(50 mol%).

0.113 g (10-3 mol) of imidazole oxalate was allowed to accumulate for 2 hours under total nitrogen, and then molarized in the same manner as in Example 1.
′? 1 reaction Complete reaction yielded colorless and transparent polycarbonate 1. The viscosity average molecule iMv of this polycarbonate is 25
,000, and the glass transition temperature was 128°C.

Example 4 2.2-bis(4-hydroxyphenyl)propane 22
．． 8 g (0.1 mol), 42.1 g (0.1 mol) bis(2,4,6-drichlorophenyl) carbonate, 0.0182 g (1σ4
After stirring at 180°C for 1 hour under nitrogen, the temperature was gradually increased while reducing the pressure, and finally the temperature was 0.1 Torr.
Polycondensation reaction is performed at 280°C for 1 hour to produce 2, 4.
6-) Lichlorophenol was distilled off to obtain a colorless and transparent polycarbonate.

When measuring the viscosity average molecular weight, Mv = 27,500
Met. Moreover, the glass transition temperature was 151°C.

Comparative Example The same treatment was carried out under exactly the same conditions as in Example 1, using pyridine carbonate instead of 2-methylimidazole carbonate, but the resulting polycarbonate had a viscosity average molecular weight Mv = 4,000. Although it had the form of polycarbonate, it had a low molecular weight that was not suitable for practical use.

(Effects of the Invention) By using a salt of an electron-donating amine compound as a catalyst, it was possible to obtain a high molecular weight, colorless and transparent polycarbonate that substantially does not contain chlorine ions without using toxic phosgene.

Claims (3)

[Claims] (1) A method for producing polycarbonate, which comprises subjecting a divalent hydroxy compound and bisaryl carbonate to melt polycondensation in the presence of a catalyst selected from salts of electron-donating amine compounds. (2) Dihydric phenols are (I), (II), (III), (
IV) A method for producing polycarbonate according to claim 1. ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(III) ▲There are mathematical formulas, chemical formulas, tables, etc.▼( IV) (R_1, R_2, R_3, R_4 are hydrogen or have 1 carbon number
~8 linear or branched alkyl group, or phenyl group, where X is a halogen atom, n = 0 to 4, m = 1 to 4) (3) A method for producing a polycarbonate copolymer according to claim 1 or 2.