JP3250312B2 - Method for producing aromatic polycarbonate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a polycarbonate by a transesterification reaction. For more information,
The present invention relates to a method for producing an aromatic polycarbonate having improved heat resistance from an aromatic diol compound and a carbonic acid diester compound by a melt polycondensation reaction.

[0002]

2. Description of the Related Art In recent years, aromatic polycarbonates have been developed as engineering plastics having excellent mechanical properties such as impact resistance and heat resistance and transparency. Carbonated beverage bottles, electronic substrates (CD substrates), transfer belts, etc. Are widely used in many fields.

As a method for producing this aromatic polycarbonate, a so-called phosgene method in which an aromatic diol such as bisphenol and phosgene are reacted by an interfacial polycondensation method has been industrialized. The heat resistance of the aromatic polycarbonate produced by this phosgene method is 5% as described later.
Approximately 500 ° C based on the weight loss heating temperature (Td5%)
And have high advantages.

[0004] However, the phosgene method which is currently practiced industrially requires the use of very toxic phosgene, the problem of treating a large amount of by-produced sodium chloride, and the methylene chloride which is usually used as a reaction solvent. Problems in the polymer that can be obtained, such as: hygiene due to the use of methylene chloride, concerns about air environment problems,
Many problems have been pointed out.

A method of obtaining an aromatic polycarbonate by a transesterification reaction between an aromatic diol compound and a carbonic acid diester has long been known as a so-called melting method or a non-phosgene method. The non-phosgene method is said to be free from the various problems of the phosgene method as described above, and has the advantage that an aromatic polycarbonate can be produced at lower cost.

[0006] However, for example, in the case of an aromatic polycarbonate prepared from bisphenol A and diphenyl carbonate by the non-phosgene method, it is generally necessary to selectively produce only a polymer having a high molecular weight and having no hydroxyl group structure in the polymer terminal structure. Is considered to be difficult, and it is considered that the presence of the hydroxyl group-terminated polymer contained in this manner is one of the reasons for the decrease in heat resistance.

That is, the heat resistance of the aromatic polycarbonate obtained by the non-phosgene method is as low as about 445 ° C. as compared with the heat resistance (about 500 ° C.) of the aromatic polycarbonate obtained by the phosgene method in which the capping reaction of the hydroxyl group terminal structure is easy. It is necessary to mold the aromatic polycarbonate at a high temperature of about 320 ° C. If the heat resistance of the polycarbonate is low, problems such as cutting of the polymer main chain, coloring, and reduction in mechanical strength occur. In particular, thin-wall molding of a hollow container (0.3 to 0.6)
mm) or a complicated shape, a particularly high temperature is required to lower the melt viscosity. Therefore, improvement of the heat resistance of the polycarbonate obtained by the non-phosgene method has become a problem in practical use.

[0008]

An object of the present invention is to provide a method for producing an aromatic polycarbonate having high heat resistance even by the above-mentioned transesterification polycondensation method (non-phosgene method).

[0009]

SUMMARY OF THE INVENTION The present invention relates to a method for producing a polycondensation reaction between an aromatic diol compound and a diester carbonate in the presence of a transesterification catalyst and a derivative of an organic carboxylic acid represented by the following formula [I]. The present invention provides a method for producing an aromatic polycarbonate.

[0010]

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Wherein M is an element of Groups I to V of the periodic table, R and R ′ are each independently a hydrocarbon group having 1 to 20 carbon atoms, and 1 is an integer of 1 to M valence. , M = an integer calculated by the valence of M−1. ]

[Specific explanation] The aromatic diol compound used in the production of the present invention is a compound represented by the general formula [II].

[0013]

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(Wherein A is a single bond, a substituted or unsubstituted linear, branched or cyclic divalent hydrocarbon group having 1 to 15 carbon atoms, and -O-, -S-, -CO -, -SO-, -S
Selected from the group consisting of divalent groups represented by O ₂ —, wherein X and Y are the same or different from each other and are selected from hydrogen, halogen, and a hydrocarbon group having 1 to 6 carbon atoms. And p and q are integers of 0 to 2. )

As such a compound, for example, bis (4-
(Hydroxydiphenyl) methane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3-t-butyl) Phenyl) propane, 2,2-bis (4-hydroxy-3,5-dithimenylphenyl) propane, 2,2-bis (4-hydroxy-
Bisphenols such as 3,5-dibromo) propane, 4,4-bis (4-hydroxyphenyl) heptane, and 1,1-bis (4-hydroxyphenyl) cyclohexane;
4,4′-dihydroxybiphenyl, 3,3 ′, 5
Biphenols such as 5'-tetrathimer-4,4'-biphenyl; bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfide, bis (4-
(Hydroxyphenyl) ether, bis (4-hydroxyphenyl) ketone, and the like.

Of these, 2,2-bis (4-hydroxyphenyl) propane is preferred. Two or more of these compounds can be used in combination (copolymer), and when a branched aromatic polycarbonate is to be produced, a small amount of a trihydric or higher polyhydric phenol can be copolymerized. . Further, in order to improve the thermal stability and hydrolysis resistance of the aromatic polycarbonate to be produced, a monohydric phenol such as pt-butylphenol or p-cumylphenol is used for sealing the hydroxyl group terminal. Kinds can also be used.

Representative examples of the carbonic diester used in the present invention include dimethyl carbonate, diphenyl carbonate, ditolyl carbonate, bis (4-chlorophenyl) carbonate and bis (2,4,6-trichlorophenyl) carbonate. . These carbonate diester compounds are generally used in excess with respect to 1 mol of the aromatic diol compound, and are used in an amount of 1.01 to 1.30 mol, preferably 1.02 to 1.20 mol. Is desirable.

As typical examples of the transesterification catalyst used in the present invention, specifically, lithium, sodium,
Acetate, carbonate, borate, nitrate of alkali metals such as potassium, alkaline earth metals such as magnesium, calcium and barium, metals such as zinc, cadmium, tin, antimony, manganese, cobalt, nickel, titanium and zirconium And known transesterification metal compound catalysts such as oxides, hydroxides, hydrides and alcoholates. Tin compound catalysts are preferably used, and two or more of these are used in combination. You can also.

Specifically, lithium hydride, lithium borohydride, sodium borohydride, potassium borohydride, rubidium borohydride, cesium borohydride, beryllium borohydride, magnesium borohydride, borohydride Calcium, strontium borohydride, barium borohydride, aluminum borohydride, titanium borohydride, tin borohydride, germanium borohydride, phenoxylithium, phenoxysodium, phenoxypotassium, phenoxyrubidium, phenoxycesium, sodium thiosulfate , Beryllium oxide, magnesium oxide, tin (IV) oxide, dibutyltin oxide, beryllium hydroxide, magnesium hydroxide, germanium hydroxide, lithium carbonate, sodium carbonate, potassium carbonate Beam, beryllium carbonate, magnesium carbonate, tin carbonate (IV), carbonate germanium, tin nitrate (IV), germanium nitrate, antimony trioxide, and the like.

[0020] These catalysts, ^10-5 to ^10-1 mol of the aromatic diol to 1 mole of the compound used as a raw material, preferably used in an amount of 10 ^-5 to 10 ^-2 mol.
A feature of the present invention resides in that an aromatic polycarbonate is produced by using a derivative of the organic carboxylic acid represented by the above formula [I] under transesterification melt polycondensation reaction conditions.

Examples of the organic carboxylic acid derivative represented by the formula [I] include lithium formate, sodium formate, potassium formate, lithium acetate, sodium acetate, potassium acetate, rubidium acetate, cesium acetate, magnesium acetate, magnesium acetate, calcium acetate, and the like. Barium acetate, yttrium acetate, cadmium acetate, cobalt acetate, cerium acetate, tin acetate, antimony acetate, silicon acetate, bismuth acetate, aluminum acetate, copper propionate, barium laurate, sodium stearate, potassium stearate, barium stearate, Zinc stearate, aluminum stearate, calcium benzoate, lithium benzoate, sodium benzoate, zinc benzoate, magnesium benzoate, barium benzoate, lithium oxalate, sodium oxalate, potassium oxalate Um, magnesium oxalate, calcium oxalate, barium oxalate, zinc oxalate, aluminum -
2-ethylhexanoate, sodium succinate, potassium succinate, calcium succinate, magnesium succinate, barium succinate, barium cyclohexane butyrate, barium-2-ethylhexanoate, di-n
-Butyltin bis (2-ethylhexanoate), di-
n-butyltin diacetate, di-n-butyltin dilaurate, bis (trimethylsilyl) adipate, ethyltriacetoxysilane, triacetoxyvinylsilane and the like. These may be used alone or in combination of two or more.

Among these organic carboxylic acid derivatives,
Bis (trimethylsilyl) adipate, barium stearate, cesium acetate, calcium acetate, tin acetate, calcium benzoate, magnesium acetate, magnesium oxalate and the like are preferred. The amount of the organic carboxylic acid derivative used in the method of the present invention is an amount sufficient to improve the heat resistance of the aromatic polycarbonate by the transesterification method melt polycondensation method. Generally, it is used in the range of 0.001 to 500 mol, preferably in the range of 0.001 to 300 mol, per 1 mol of the transesterification catalyst used.

The amount of the organic carboxylic acid derivative to be used is 5 × 10 ^{-9 to} 5 × 10 ^-1 mol per ¹ mol of the aromatic diol. The addition timing of the organic carboxylic acid derivative may be any stage in the transesterification melt polycondensation step as long as the effect is recognized. Conveniently, it can be added and mixed at the same time as the starting monomer such as the aromatic diol compound, the carbonic acid diester compound and the transesterification catalyst from the beginning of the reaction, or can be added at the final stage of the polycondensation reaction step. Can also be used.

The transesterification melt polycondensation method of the present invention is a method for melt polycondensation of a known aromatic polycarbonate except that a derivative of the organic carboxylic acid represented by the formula (I) is used in any of the reaction steps. It can be done legally. (By H. Schnell; "Chem"
istry and Physics of Poly
carbonates ”, Interscience 19
64).

That is, melt polycondensation is carried out using the above-mentioned raw materials while removing by-products by transesterification under heating / normal pressure or reduced pressure. The reaction is generally carried out in two or more stages. In the first-stage reaction, the raw material and the catalyst are placed in an inert gas atmosphere at normal pressure or under pressure for 100 hours.
The reaction is carried out by heating to a temperature of from 200C to 200C, during which transesterification and formation of low molecular weight oligomers (number average molecular weight 400 to 1,000) occur. In the second stage reaction, the yarn is further heated (200 ° C. to 250 ° C.)
By removing alcohol or phenol generated under reduced pressure (20 Torr or less) from the reaction system, the transesterification reaction, the formation of low molecular weight oligomer and the elongation reaction thereof proceed (number average molecular weight of 1,000 to 1,000). 7,000). Further, in order to extend the chain length of the oligomer, a high temperature (250 ° C. to 33 ° C.) is used.
(0 ° C.) and high vacuum (1 Torr or less) to remove mainly alcohols or phenols and carbonic acid diesters from the reaction system to obtain a high molecular weight aromatic polycarbonate.

The reaction time of each stage can be appropriately determined according to the degree of progress of the reaction. From the viewpoint of the hue of the obtained polymer, the hue may be slightly longer under a temperature condition of about 200 ° C. It does not have a significant adverse effect on S.A., but is generally 0.5 to 5 hours at a temperature of 200 to 250 ° C.
At a reaction temperature exceeding 250 ° C. for 1 to 3 hours, a long time reaction has a significant adverse effect on the hue. For this reason, the reaction time in the final step is preferably within 1 hour, preferably 0.1 to 1 hour (although it is related to the molecular weight).

The derivative of the organic carboxylic acid of the present invention is added and used in any of the above reaction steps. The aromatic polycarbonate obtained by the method of the present invention has a number average molecular weight (Mn) of about 1,000 to 20,000 and a weight average molecular weight (Mw) of 2,000 to 50,000.
It has a high molecular weight of about 00 and an Mw / Mn value of 2
To 4 are preferable.

The aromatic polycarbonate is about 10%.
mg was weighed, and the temperature was raised at a rate of 20 ° C./min in a nitrogen stream using a thermogravimetric analyzer 200-TG / DTA220 (trade name) manufactured by Seiko Electronics Industry Co., Ltd. The weight of the aromatic polycarbonate is 5% of the original weight.
% Is defined as the heat-resistant temperature (Td5%), this temperature is 445 ° C. or higher, preferably 460 to 5%.
20 ° C.

The hydroxyl group concentration of the polycarbonate is preferably about 0.2% by weight or less.

[0030]

EXAMPLES Hereinafter, the method of the present invention will be described specifically with reference to examples. The analysis of the aromatic polycarbonate obtained by the present invention was performed by the following measurement method. (I) Concentration of hydroxyl group in polycarbonate E. FIG. McGrath et al. (Polymer,
preprints, 19 (1), 494 (197)
According to 8)), UV spectrum analysis was performed, and the hydroxyl group concentration in the polymer sample was determined as% by weight. (Ii) Molecular weight It was measured using GPC (gel permeation chromatography) (HLC-8020 manufactured by Tosoh Corporation).

Example 1 1.0 mol (228 g) of bisphenol A, 1.08 mol (231 g) of diphenyl carbonate and 0.20 mmol (5 g) of dibutyltin oxide as a catalyst
0 mg) was placed in a SUS reactor having an internal volume of 3 liters equipped with a stirrer and a distilling device, and kept in a molten state at 150 ° C. for 1 hour under a nitrogen atmosphere. After the temperature was raised to 200 ° C., the pressure was gradually increased to 20 Torr. , And the state was maintained for 1 hour to distill phenol.

Next, the temperature of the reaction system was raised to 250 ° C., and bis (trimethylsilyl) adipate 10 mmol (2.9 mmol) was added.
g) was added, and the pressure in the system was increased to 0.5 Torr at the same temperature.
And the polycondensation reaction was performed for 1 hour.
g was obtained. Table 1 shows the analysis results of the obtained polymer.

Comparative Example 1 A polymer was synthesized under the same conditions and in the same manner as in Example 1 except that bis (tritimersilyl) adipate was not used. Table 1 shows the analysis results of the obtained polymer.

Examples 2 to 3 Polymers were prepared under the same conditions and methods as in Example 1 except that the amount of bis (trimethylsilyl) adipate used in Example 1 was changed to the amount shown in Table 1, respectively. Was synthesized. Table 1 shows the analysis results of the obtained polymer. Example 4

A reaction was carried out in the same manner as in Example 1 except that the timing of adding bis (tritimersilyl) adipate was changed. That is, bis (trimethylsilyl) adipate is reacted at 250 ° C./0.5 Torr.
After 45 minutes have passed during the reaction,
The reaction was continued under the same conditions for minutes to obtain a polymer. Table 1 shows the analysis results of the obtained polymer.

[0036]

[Table 1]

Example 5 1.0 mol (228 g) of bisphenol A, 1.08 mol (231 g) of diphenyl carbonate, 1.42 × 10 ^-2 mmol (10 mg) of barium stearate and 0.20 mmol (50 mg) of dibutyltin oxide as a catalyst ) Was placed in a SUS reactor having an internal volume of 3 liters equipped with a stirrer and a distilling device.
For 1 hour. After the temperature was raised to 200 ° C., the pressure was gradually increased to 20 Torr. , And the state was further maintained for 1 hour to distill phenol. Then 25
The temperature was raised to 0 ° C. and the system pressure was reduced to 0.5 Torr at the same temperature.
And the polycondensation reaction was performed for 1 hour.
g was obtained. Table 2 shows the analysis results of the obtained polymer.

Example 6 Calcium benzoate as an organic carboxylic acid derivative
A polymer was synthesized according to the melt polycondensation reaction step described in Example 5 except that 95 × 10 ⁻² mmol (20 mg) was used. Table 2 shows the analysis results of the obtained polymer.

Example 7 As a derivative of an organic carboxylic acid, cesium acetate 5.23 ×
A polymer was synthesized according to the melt polycondensation reaction step described in Example 5 except that 10 ^-2 mmol (10 mg) was used.
Table 2 shows the analysis results of the obtained polymer.

Examples 8 to 12 Polymers were synthesized under the same conditions as in Example 5 using various organic carboxylic acid derivatives shown in Table 2. Table 2 shows the analysis results of the obtained polymer.

[0041]

[Table 2]

[0042]

According to the non-phosgene method for producing an aromatic polycarbonate by subjecting an aromatic diol compound and a carbonic acid diester compound to a melt polycondensation reaction using a transesterification catalyst, the melt polycondensation reaction is carried out with an organic carboxylic acid. By performing the reaction in the presence of an acid derivative, an aromatic polycarbonate having improved heat resistance can be obtained although the concentration of hydroxyl groups at the molecular terminals of the obtained aromatic polycarbonate is not significantly reduced (Examples 1 to 4). ). Also,
Depending on the type of the derivative of the organic carboxylic acid, the hydroxyl group concentration of the obtained aromatic polycarbonate can be reduced, and the heat resistance can be improved (Examples 5 to 12).

Continuation of front page (56) References Patent 3221104 (JP, B2) European Patent Application Publication 479107 (EP, A2) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 64/00-64 / 42

Claims (2)

(57) [Claims] 1. An aromatic polycarbonate is produced by subjecting an aromatic diol compound and a carbonic acid diester compound to a melt polycondensation reaction in the presence of a transesterification catalyst and a derivative of an organic carboxylic acid represented by the following formula [I]. Method. Embedded image [Wherein, M is an element in Groups I to V of the periodic table, R and R ′ are each independently a hydrocarbon group having 1 to 20 carbon atoms, l is an integer from 1 to M, and m = It is an integer calculated by the valence of M-1. ] 2. The derivative of an organic carboxylic acid is lithium formate, sodium formate, potassium formate, lithium acetate, sodium acetate, potassium acetate, rubidium acetate, cesium acetate, magnesium acetate, calcium acetate, barium acetate, yttrium acetate, cadmium acetate. , Cobalt acetate, cerium acetate, tin acetate, antimony acetate, silicon acetate, bismuth acetate, aluminum acetate, copper propionate, barium laurate, sodium stearate, potassium stearate, barium stearate, zinc stearate, aluminum stearate, Calcium benzoate, lithium benzoate, sodium benzoate, zinc benzoate, magnesium benzoate, barium benzoate, lithium oxalate, sodium oxalate, potassium oxalate, magnesium oxalate, calcium oxalate Cium, barium oxalate, zinc oxalate,
Aluminum 2-ethylhexanoate, sodium succinate, potassium succinate, calcium succinate, magnesium succinate, barium succinate, barium cyclohexane butyrate, barium-2-ethylhexanoate, di-n-butyltin bis (2 -Ethylhexanoate), di-n-butyltin diacetate, di-n-
The method for producing an aromatic polycarbonate according to claim 1, which is a compound selected from butyltin dilaurate, bis (trimethylsilyl) adipate, ethyltriacetoxysilane, and triacetoxyvinylsilane.