JPH05140290A - Production of polycarbonate - Google Patents

Abstract

PURPOSE:To produce a polycarbonate having an improved clarity by conducting the melt polycondensation of a dihydroxy compd. with a bisaryl carbonate in a reaction apparatus made of a specific material. CONSTITUTION:The melt polycondensation of a dihydroxy compd. of one of formulas I to 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) with a bisaryl carbonate is conducted at 100-300 deg.C in the presence of a transesterification catalyst consisting of an electron-donating amine compd. or consisting of the amine compd. and an alkali or alkaline earth metal compd. in a reaction apparatus made of a material contg. at least 60% Cu and/or Ni.

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 polycarbonate, particularly a colorless and transparent high molecular weight polycarbonate.
Manufacturing method

[0002]

BACKGROUND OF THE INVENTION Polycarbonates are versatile engineering thermoplastics having a wide range of applications, especially for injection molding or as a glass sheet alternative to window glass. ..

Conventionally, an interfacial polycondensation method, a transesterification method and the like have been applied to the production of these polycarbonates.

The interfacial polycondensation method is generally used for polycarbonate.
However, it has drawbacks such as the use of toxic phosgene and chlorine ion remaining in the polycarbonate produced. In order to solve these drawbacks, liquid trichloromethyl chloroformate, which is a dimer of phosgene, is used in place of toxic phosgene, and an interfacial polycondensation reaction with a special divalent phenol is carried out to obtain a polymer. A method for producing a bonnet is disclosed in JP-A-63-1823.
However, there is only a description of 9,9-bis (4-hydroxyphenyl) fluorenes as a special divalent phenol.
Also, a method of obtaining polycarbonate from 2,2-bis (4-hydroxyphenyl) propane by using triphosgene instead of toxic phosgene is described in Angew. Ch
em. (Angevante, Hemi-) 99.922 (198)
7), German Patent DE 3440141, but a reaction mechanism for generating phosgene is also proposed.

In the transesterification reaction, a transesterification catalyst is added to diphenyl carbonate and an aromatic dihydroxy compound to synthesize a prepolymer while distilling phenol under heating and reduced pressure. Under vacuum, 290
A high molecular weight polycarbonate is obtained by heating above the temperature to distill the phenol (US Pat. No. 4,345,062), but the high molecular weight polycarbonate is another engineering plastic. In contrast to that, since the melt viscosity is extremely large, a high temperature of 290 ° C or higher is required as a reaction condition, and a high vacuum (10 ^-2 Torr) is required to distill off a phenol having a high boiling point. Therefore, it is known that industrialization is difficult from the viewpoint of equipment and there are problems in terms of hue and physical properties.

However, the transesterification method has been studied variously because it can carry out the reaction by melt polycondensation and is an industrially economical method. In particular, the influence of the material of the reactor is suggested from the viewpoint of product coloring, and as described in JP-A-55-142025, the polycarbonate obtained when a stainless reactor is used. It is suggested that it is difficult to produce a product having satisfactory physical properties and hue, since it is difficult to obtain a polymer having a high molecular weight.
Further, although a special catalyst has been found by studying various catalysts, it was not always sufficiently satisfactory. Further, although it is different from the starting material of the present invention, US Pat. No. 4,383,092 also describes the material related to the reactor.

[0007]

Means for Solving the Problems The inventors of the present invention have earnestly studied the high molecular weight and the coloring of resins, which are one of the problems of the transesterification method conventionally used for the production of polycarbonate. The present invention has been completed by finding the fact that a colorless and transparent high molecular weight polycarbonate can be obtained by using a special material as the material of the reactor, especially for the liquid contact part.

That is, the present invention relates to a dihydric hydroxy compound and a bisaryl carbonate in the presence of a transesterification catalyst.
In the method of producing a polycarbonate by melt-polycondensation of a polyester by a transesterification method, the quantitative relationship of the composition constituted as the material of the reactor is such that the contents of Cu and Ni are 60.
By using a material consisting of 10% by weight or more, a method for producing a polycarbonate for obtaining a high molecular weight colorless and transparent resin is provided. Typical examples of the transesterification catalyst that can be used in the present invention include (a) a catalyst containing a metal-containing catalyst, such as lithium borohydride, sodium borohydride, potassium borohydride, rubidium borohydride, and hydrogenation. Cesium borohydride, beryllium borohydride, magnesium borohydride, calcium borohydride, strontium borohydride, barium borohydride, aluminum borohydride, titanium borohydride, tin borohydride, germanium borohydride, tetraphenoxy Lithium, tetraphenoxy sodium, tetraphenoxy potassium, tetraphenoxy rubidium, tetraphenoxy cesium, sodium thiosulfate, beryllium oxide, magnesium oxide, tin oxide (4
Value), dibutyltin oxide, beryllium hydroxide, magnesium hydroxide, germanium hydroxide, beryllium acetate, magnesium acetate, tin acetate (tetravalent), germanium acetate, lithium carbonate, sodium carbonate, potassium carbonate, beryllium carbonate, magnesium carbonate, carbonate Tin (4
Valence), germanium carbonate, tin nitrate (tetravalent), germanium nitrate, artimon trioxide, bismuth trimethylcarboxylate and the like.

(B) As a catalyst similar to the electron-donating amine compound, N, N-dimethyl-4-aminopyridine,
4-diethylaminopyridine, 4-aminopyridine, 2
-Aminopyridine, 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 4-hydroxypyridine, 2-dimethylaminoimidazole, 2-mitoxyimidazole, 2-mercaptoimidazole, aminoquinoline, imidazole 2-methyl imidazole,
4-methylimidazole, diazabicyclooctane (D
ABCO) and the like.

Further, (c) carbonic acid, acetic acid, formic acid, nitric acid, nitrous acid, oxalic acid, fluoroboric acid, hydrofluoric acid salt and the like of the above-mentioned electron donating amine compound can be mentioned.

(D) As catalysts similar to electron-donating phosphorus compounds, triethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triphenylphosphine, tri-o-
Examples thereof include dimethoxyphenylphosphine, tri-p-tolylphosphine, tri-o-tolylphosphine, tolylbutylphosphite, triphenylphosphite, tri-p-tolylphosphite and tri-o-tolylphosphite.

Further, as a catalyst similar to borane complex (e), a complex of borane and the following compounds, that is, ammonia, dimethylamine, trimethylamine, triethylamine, t-butylamine, dimethylaniline, pyridine, dimethylaminopyridine, morpholine, Examples thereof include complexes such as piperazine, pyrrole, tetrahydrofuran, dimethyl sulfide, tri-n-butylphosphine, triphenylphosphine and triphenylphosphite. Particularly preferred transesterification catalysts include an electron donating amine compound or a combination of an electron donating amine compound and an alkali metal compound or an alkaline earth metal compound.

Examples of the divalent hydroxy compound used in the present invention include compounds represented by Chemical formulas 1 to 4.

Specifically, 2,2-bis- (4-gidroxyphenyl) propane, 2,2-bis- (4-hydroxyphenyl) butane, 2,2-bis- (4-hydroxyphenyl)- 4-methylpentane, 2,2-bis-
(4-hydroxyphenyl) octane, 4,4'-hydroxy-2,2,2-triphenylethane, 2,2-bis- (3,5-dibromo-4-hydroxyphenyl) 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-tert-butylphenyl) propane,
1,1'-bis- (4-hydroxyphenyl) -p-diisopropylbenzene, 1,1'-bis- (4-hydroxyphenyl) -m-diisopropylbenzene, 1,1
-Bis- (4-hydroxyphenyl) cyclohexane and the like can be mentioned. Furthermore, copolymerized polycarbonate by combining two or more divalent hydroxy compounds.
It is also possible to manufacture Examples of the bisaryl carbonate include diphenyl carbonate and bis (2,4
-Dichlorophenyl) carbonate, bis (2,4,6)
-Trichlorophenyl) carbonate, bis (2-cyanophenyl) carbonate, bis (o-nitrophenyl) carbonate, ditolylcarbonate, m-cresylcarbonate, Examples include dinaphthyl carbonate and bis (diphenyl) carbonate. Diphenyl carbonate is preferred.

In the production method of the present invention, a divalent hydroxy compound such as bisphenol A is added to bisphenyl carbonate by using at least one of the above-mentioned transesterification catalysts.
It is carried out by a melt polycondensation reaction with a bis-arylcarbonate such as a polyester.

The temperature at which this reaction proceeds is from 100 ° C to about 3 ° C.
The range is up to 00 ° C. The reaction temperature is preferably in the range of 130 ° C to 280 ° C. Reaction temperature is 13
If it is lower than 0 ° C, the reaction rate becomes slow, and if it exceeds 280 ° C, side reactions easily occur. At least one compound is selected as the catalyst, it requires a 10 ^-6 mol to 10 ^-1 mol with respect to the divalent hydroxy compound present in the reaction system, 10 preferably from 10 ^-2 mol ^- It is ⁵ mol. When the amount of the catalyst is less than 10 ^-6 mol, the catalytic action is small and the polymerization rate of the polycarbonate is slow, and when the amount of the catalyst is 10 ^-1 mol or more, it remains in the produced polycarbonate. As a result, the physical properties of the polycarbonate are deteriorated.

The required amount of bisaryl carbonate is equimolar to the divalent hydroxy compound present in the reaction system. Generally, in order to form a high molecular weight polycarbonate, 1 mol of the carbonate compound and 1 mol of the divalent hydroxy compound must be reacted.

However, from the industrial point of view, the conventional method is to use 1.0% of bisaryl carbonate with respect to the hydroxy compound.
It has been treated with an excess of 0 to 1.10 moles of bis-aryl carbonate and is included as a condition of the invention.

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

[0020]

[Example 1] Cupronickel C7060 (C
u 90%, Ni 10%) reactor 2,2-bis (4
-Hydroxyphenyl) propane 22.8 g (0.1 mol), 2-methylimidazole 0.0164 g (2 x 1
^0-4 mol) and bisphenol carbonate 21.9.
g (0.1023 mol), 180 ° C under nitrogen atmosphere
After stirring for 1 hour, the temperature is gradually reduced while raising the temperature, and finally polycondensation reaction is performed at 0.1 Torr and 270 ° C. for 2 hours.
The phenol produced is distilled off to give a colorless and transparent polymer.
I got a bonus.

The viscosity average molecular weight (Mv) of the obtained polycarbonate was Mv = 34000.
Further, the hue was A ₃₈₀ -A ₅₈₀ = 0.11.

The method of measuring the viscosity average molecular weight is 2
The intrinsic viscosity [η] of the methylene chloride solution at 0 ° 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 hue was evaluated by using a 10% methylene chloride solution of polycarbonate as a UV measuring device of 380 μm and 580 μm.
The difference in absorbance in the wavelength region of is measured and displayed. The larger the value, the more the coloring.

[0023]

[Example 2] Cupronickel C7100 (Cu
80%, Ni 20%) reactor vessel, and as a transesterification catalyst instead of 2-methylimidazole, 4
-Dimethylaminopyridine 0.0061 g (5 x 10 ^-5
Mol) was used and the same reaction as in Example 1 was carried out to obtain a polycarbonate.

The viscosity average molecular weight (Mv) of the obtained polycarbonate was Mv = 32000.
Further, the hue was A ₃₈₀ -A ₅₈₀ = 0.07.

[0025]

[Example 3] Cupronickel (Cupronickel) C7150 (C
u70%, Ni30%), using 4-dimethylaminopyridine 0.006 as a transesterification catalyst.
1 g (5 × 10 ^-5 mol) and potassium acetate 0.0002 g
The same reaction as in Example 1 was carried out except that (2 × 10 ⁻⁶ mol) was used to obtain a polycarbonate.

The viscosity average molecular weight (Mv) of the obtained polycarbonate was Mv = 36000.
Further, the hue was A ₃₈₀ -A ₅₈₀ = 0.09.

[0027]

Example 4 Using a reaction vessel made of Pyrex glass,
Cu powder 100ppm was added to the charged amount,
The reaction was carried out with the same formulation as in Example 2.

The viscosity average molecular weight (Mv) of the obtained polycarbonate was measured, Mv = 29000, and the hue was A.
₃₈₀ - _A580 = 0.09.

[0029]

[Embodiment 5] Cu powder 20 ppm, Ni powder 80 ppm
The reaction was performed in the same manner as in Example 3 except that was added.

When the viscosity average molecular weight (Mv) of the obtained polycarbonate was measured, Mv = 34000, the hue was A
₃₈₀ - _A580 = 0.12.

[0031]

[Comparative Example 1] Stainless steel (SUS316: Fe67%,
(Cr 18%, Ni 12%, Mo 25%, C 0.06%)
Was used in the same manner as in Example 2 to obtain a polycarbonate.

The viscosity average molecular weight (Mv) of the obtained polycarbonate was Mv = 18,000.
Moreover, the hue was A ₃₈₀ −A ₅₈₀ = 0.319.

[0033]

[Comparative Example 2] Stainless steel (SUS304: Fe74%,
Cr 18%, Ni 8%, C 0.06%) was used to carry out the reaction in the same manner as in Example 2 to obtain a polycarbonate.

The viscosity average molecular weight (Mv) of the obtained polycarbonate was Mv = 17,000.
Further, the hue was A ₃₈₀ -A ₅₈₀ = 0.354.

[0035]

Comparative Example 3 Using a reactor made of carbon steel (SS-41),
Reaction was carried out in the same manner as in Example 2 to obtain a polycarbonate.

The viscosity average molecular weight (Mv) of the obtained polycarbonate was Mv = 14300. Moreover, the hue was A ₃₈₀ −A ₅₈₀ = 0.429.

[0037]

According to the present invention, a colorless and transparent polycarbonate having a high molecular weight and no coloring can be obtained.

Claims (4)

[Claims] 1. A method for producing a polycarbonate by melt polycondensation of a divalent hydroxy compound and a bisaryl carbonate by a transesterification method in the presence of a transesterification catalyst, which is used as a material for a reactor. A method for producing a polycarbonate, characterized in that a transesterification reaction is carried out using a material having a quantitative relationship of textures constituted by Cu and / or Ni content of 60% or more. 2. A method for producing a polycarbonate, wherein the material which comes into contact with the reactant in the above-mentioned production method has the composition according to claim 1. 3. The method for producing a polycarbonate according to claim 1, wherein the transesterification catalyst comprises an electron-donating amine compound or an electron-donating amine compound in combination with an alkali metal compound or an alkaline earth metal compound. 4. A divalent hydroxy compound is represented by the following chemical formulas 1, 2,
The method for producing a polycarbonate according to claim 1, which is a compound represented by 3 or 4. [Chemical 1] [Chemical 2] [Chemical 3] [Chemical 4] (In the formula, R ₁ , R ₂ , R ₃ , R ₄ , and R ₅ each represent a hydrogen atom, a linear or branched alkyl group having 1 to 8 carbon atoms, or a phenyl group, and X represents a halogen atom. ,
n = 0 to 4 and m = 1 to 4. )