JPH06287294A - Production of aromatic polycarbonate - Google Patents

Abstract

PURPOSE:To obtain an aromatic polycarbonate having excellent heatresistance and transparency and useful for electronic substrate, etc., by carrying out melt- polycondensation reaction of an aromatic diol with a carbonic acid diester compound in the presence of a transesterification catalyst and a specific organic carboxylic acid derivative. CONSTITUTION:The objective aromatic polycarbonate is produced by the melt- polycondensation reaction of an aromatic diol compound such as 2,2-bis(4- hydroxyphenyl)propane with a carbonic acid diester compound such as diphenyl carbonate in the presence of a transesterification catalyst such as sodium phenolate and an organic carboxylic acid derivative of formula (M is group I to V element of the periodic table; R and R' are 1-20C hydrocarbon group; (l) is integer of 1 to the atomic valence of M; (m) is integer equal to the atomic valence of M minus 1) such as lithium formate.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polycarbonate by a transesterification reaction. For more details,
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 used as carbonated beverage bottles, electronic substrates (CD substrates), transfer belts as engineering plastics having excellent mechanical properties such as impact resistance, heat resistance and transparency. It is 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 when the weight loss heating temperature (Td 5%) is used as a scale
And has high advantages.

However, the phosgene method currently practiced industrially requires the use of extremely toxic phosgene, the problem of treating a large amount of by-produced sodium chloride, and methylene chloride usually used as a reaction solvent. The problem of being mixed in the obtained polymer: Hygiene due to the use of methylene chloride, concern about atmospheric environment problems, etc.
Many problems have been pointed out.

Further, a method of obtaining an aromatic polycarbonate by transesterification of an aromatic diol compound and a carbonic acid diester has long been known as a so-called melting method or non-phosgene method. The non-phosgene method is said to have the advantages that the above-mentioned various problems of the phosgene method do not occur and that the aromatic polycarbonate can be produced at a lower cost.

However, for example, in the aromatic phosgene-based aromatic polycarbonate from bisphenol A and diphenyl carbonate, generally, only a polymer having a high molecular weight and not having a hydroxyl group structure in its polymer terminal structure is selectively produced. It is said that the presence of the hydroxyl group-terminated polymer thus contained 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 about 445 ° C., which is lower than the heat resistance of the aromatic polycarbonate obtained by the phosgene method (about 500 ° C.), which facilitates the sealing reaction of the hydroxyl terminal structure. It is necessary to mold the aromatic polycarbonate at a high temperature of about 320 ° C., and if the heat resistance of the polycarbonate is low, problems such as cutting of the polymer main chain, coloring, and deterioration of mechanical strength occur. Especially thin molding of hollow containers (0.3-0.6
mm) or a complex shape, a high temperature is particularly required to reduce the melt viscosity, and therefore improvement in heat resistance of the polycarbonate obtained by the non-phosgene method is a problem for practical use.

[0008]

SUMMARY OF THE INVENTION 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]

The present invention relates to a melt polycondensation reaction of an aromatic diol compound and a carbonic acid diester compound in the presence of a transesterification reaction 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]

[Chemical 2]

[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 l is an integer from 1 to a valence of M. , M = the valence of M−l is an integer calculated. ]

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

[0013]

[Chemical 3]

(In the formula, 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
It is selected from the group consisting of divalent groups represented by O ₂ —, X and Y are the same or different from each other, and selected from hydrogen, halogen, or a hydrocarbon group having 1 to 6 carbon atoms. And p and q are integers of 0 to 2. )

Examples of such compounds include 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-dithymerphenyl) 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'-tetrathymer-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 preferable. Two or more kinds of these compounds may be used in combination (copolymer), or when a branched aromatic polycarbonate is to be produced, a small amount of trihydric or higher polyhydric phenol may be copolymerized. . Further, for the purpose of improving the thermal stability and hydrolysis resistance of the aromatic polycarbonate produced, monohydric phenols such as pt-butylphenol and p-cumylphenol are used for the purpose of sealing the hydroxyl terminal. Kinds can also be used.

Representative examples of the carbonic acid diester used in the present invention include dimethyl carbonate, diphenyl carbonate, ditolyl carbonate, bis (4-chlorophenyl) carbonate, bis (2,4,6-trichlorophenyl) carbonate and the like. . These carbonic acid 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 reaction catalyst used in the present invention, specifically, lithium, sodium,
Alkali metals such as potassium, alkaline earth metals such as magnesium, calcium and barium, acetates, carbonates, borates and nitrates of metals such as zinc, cadmium, tin, antimony, manganese, cobalt, nickel, titanium and zirconium. Well-known transesterification metal compound catalysts such as oxides, hydroxides, hydrides and alcoholates can be mentioned, and tin compound catalysts are preferably used, and these are used in combination of two or more kinds. 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, phenoxy lithium, phenoxy sodium, phenoxy potassium, phenoxy rubidium, phenoxy cesium, 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 is that an aromatic polycarbonate is produced by using the derivative of the organic carboxylic acid represented by the above formula [I] under the conditions of the transesterification melt polycondensation reaction.

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, 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, calcium oxalate. Um, magnesium oxalate, calcium oxalate, barium oxalate, zinc oxalate, aluminum -
2-ethylhexanoate, sodium succinate, potassium succinate, calcium succinate, magnesium succinate, barium succinate, barium cyclohexanebutyrate, barium-2-ethylhexanoate, di-n
-Butyltin bis (2-ethylhexanoate), di-
Examples include n-butyltin diacetate, di-n-butyltin dilaurate, bis (trimethylsilyl) adipate, ethyltriacetoxysilane, triacetoxyvinylsilane. 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 preferable. 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 0.001 to 300 mol, based on 1 mol of the transesterification catalyst used.

The amount of the organic carboxylic acid derivative used is 5 × 10 ^{-9 to} 5 × 10 ^-1 mol per ¹ mol of the aromatic diol. The organic carboxylic acid derivative may be used and added at any stage during the transesterification melt polycondensation step as long as the effect is recognized. For convenience, the aromatic diol compound, the carbonic acid diester compound, the transesterification reaction catalyst, etc., which are the raw material monomers, can be added and mixed at the same time from the initial stage of the reaction, or added at the final stage of the polycondensation reaction process. It can also be used.

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

That is, melt polycondensation is carried out using the above-mentioned raw materials while removing by-products by a transesterification reaction under heating / normal pressure or reduced pressure. The reaction is generally carried out in a multi-step process of two or more steps. In the first-step reaction, the raw material and the catalyst are heated to 100 at atmospheric pressure or under an inert gas atmosphere.
It is carried out by heating to a temperature of ℃ to 200 ℃, during which a transesterification reaction and a reaction for forming a low molecular weight oligomer (number average molecular weight of 400 to 1,000) occur. In the second stage reaction, the yarn is further heated (200 ° C to 250 ° C),
The alcohol or phenol generated by reducing the pressure (20 Torr. Or less) is removed from the reaction system to promote the transesterification reaction, the formation of a low molecular weight oligomer and the chain extension reaction thereof (number average molecular weight of 1,000 to 7,000). Furthermore, in order to extend the chain length of the oligomer, a high temperature (250 ° C to 33 ° C)
A high molecular weight aromatic polycarbonate is obtained by removing mainly alcohols or phenols and carbonic acid diesters from the reaction system under conditions of high vacuum (0 ° C.) (1 Torr. Or less).

The reaction time of each step can be appropriately determined according to the degree of progress of the reaction. From the viewpoint of the hue of the polymer obtained, the reaction time is slightly longer under the temperature condition of about 200 ° C. However, it is generally 0.5 to 5 hours, and at a temperature of 200 to 250 ° C.
When the reaction temperature is 1 to 3 hours and exceeds 250 ° C., the reaction for a long time has a remarkable adverse effect on the hue. Therefore, it is preferable that the reaction time in the final step is within 1 hour, preferably 0.1 to 1 hour (although it is related to the molecular weight).

The organic carboxylic acid derivative 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 has an Mw / Mn value of 2
-4 are preferable.

Further, about 10 parts of this aromatic polycarbonate
When a precise amount of mg is used and the temperature is raised in a nitrogen stream at a temperature rising rate of 20 ° C./min using a thermogravimetric analyzer 200-TG / DTA220 (trade name) manufactured by Seiko Instruments Inc. , The weight of this aromatic polycarbonate is 5% of the original weight.
Assuming that the temperature at which the decrease in temperature reaches% is the heat resistant temperature (Td 5%), this temperature is 445 ° C. or higher, preferably 460 to 5
It is 20 ° C.

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

[0030]

EXAMPLES Hereinafter, the method of the present invention will be specifically described with reference to Examples. The aromatic polycarbonate obtained by the present invention was analyzed by the following measuring method. (I) Hydroxyl group concentration in polycarbonate J. E. Methods such as McGrath (Polymer,
prepprints, 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 Bisphenol A 1.0 mol (228 g), diphenyl carbonate 1.08 mol (231 g) and dibutyltin oxide 0.20 mmol (5 as catalyst)
0 mg) was placed in a SUS reactor equipped with a stirrer and a distillation device having an internal volume of 3 liters, 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.

Then, the temperature of the reaction system was raised to 250 ° C., and 10 mmol (2.9 of bis (trimethylsilyl) adipate was used.
g) was added, and the pressure in the system was adjusted to 0.5 Torr.
To about 250 for about 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 method as in Example 1 except that bis (trithymersilyl) 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 method as in Example 1, except that the amount of bis (trimethylsilyl) adipate used in Example 1 was changed to the amounts shown in Table 1. Was synthesized. Table 1 shows the analysis results of the obtained polymer. Example 4

The same reaction as in Example 1 was carried out except that the addition timing of bis (trithymersilyl) adipate in Example 1 was changed. That is, bis (trimethylsilyl) adipate was added at 250 ° C./0.5 Torr.
45 minutes after the completion of the reaction, the addition was continued for 15 minutes.
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 equipped with a stirrer and a distillation device having an internal volume of 3 liters, and heated at 150 ° C under a nitrogen atmosphere.
The molten state was maintained for 1 hour. After the temperature was raised to 200 ° C., the pressure was gradually increased to 20 Torr. Then, the state was maintained for 1 hour to distill the phenol. Then 25
The temperature was raised to 0 ° C., and at the same temperature, the system low pressure was adjusted to 0.5 Torr.
To about 250 for about 1 hour
g was obtained. Table 2 shows the analysis results of the obtained polymer.

Example 6 Calcium benzoate as a derivative of organic carboxylic acid
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 Cesium acetate 5.23 × as a derivative of an organic carboxylic acid
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 by using the various organic carboxylic acid derivatives shown in Table 2 under the same conditions as in Example 5. Table 2 shows the analysis results of the obtained polymer.

[0041]

[Table 2]

[0042]

INDUSTRIAL APPLICABILITY In the method of producing an aromatic polycarbonate by subjecting an aromatic diol compound and a carbonic acid diester compound to a melt polycondensation reaction using a non-phosgene method transesterification reaction catalyst, the melt polycondensation reaction is carried out by using an organic carboxylic acid. By carrying out 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 ends of the obtained aromatic polycarbonate is not significantly reduced (Examples 1 to 4). ). Also,
Depending on the kind of the organic carboxylic acid derivative, the hydroxyl group concentration of the obtained aromatic polycarbonate can be lowered and the heat resistance can be improved (Examples 5 to 12).

Claims (2)

[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 an organic carboxylic acid derivative represented by the following formula [I]. Method. [Chemical 1] [In the formula, M is an element of Group 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 a valence of M, and m = It is an integer calculated by the valence of M-1. ] 2. A 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 Sium, barium oxalate, zinc oxalate,
Aluminum-2-ethylhexanoate, sodium succinate, potassium succinate, calcium succinate, magnesium succinate, barium succinate, barium cyclohexanebutyrate, 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.