JPH09235364A - Production of polyester and polyestercarbonate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply obtain the subject polymers low in coloration degrees, respectively, at a low cost without using a halogen-containing compound and a solvent, by reacting a polycarbonate with a dicarboxylic acid diester at a specific temperature. SOLUTION: (B) A polycarbonate such as a compound of the formula R<1> is a divalent 1-20C hydrocarbon group (substituted with one or more of halogen groups, hydrocarbon groups, alkoxy groups or phenoxy groups) or a divalent aromatic hydrocarbon group (substituted with one or more of halogen groups, hydrocarbon groups, alkoxy groups or phenoxy groups); X is O, S, SO, SO2 , CO, a 1-20C hydrocarbon group]; (a) is 1-50000} [e.g. a 2,2-bis(4-hydroxyphenyl) propane polycarbonate] is reacted with (C) a dicarboxylic acid diester (e.g. dimethyl terephthalate, dimethyl isophthalate, dimethyl naphthalene-2,6- dicarboxylate) in the presence of (A) an esterification or transesterification catalyst at a reaction temperature of <=300 deg.C over the whole time of the reaction.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing polyester or polyester carbonate.

[0002]

Polyesters and polyester carbonates are industrially useful molding materials generally used for plastic containers, films, fibers, adhesives, extruded sheets and the like. In particular, terephthalic acid and / or isophthalic acid, a carbonate component, and 2,2-bis (4-
Polyester carbonate resin containing hydroxyphenyl) propane (also known as bisphenol A) as the main unit,
And a polyester resin containing terephthalic acid and / or isophthalic acid and bisphenol A as main units,
It has excellent mechanical properties, electrical properties, heat resistance, dimensional stability, and transparency, and its molded products are widely used.

As a method for producing polyesters and polyester carbonates, an interfacial polycondensation method by reacting phosgene and / or dicarboxylic acid chloride with an alkali salt of diols is generally used. The interfacial polycondensation reaction is characterized in that it can be carried out at a low temperature, a high molecular weight product is easily obtained, and the obtained polymer is also low in color. However, in this method, it is difficult to obtain the raw materials phosgene and acid chloride. Considering recent environmental problems, the use of halogen-based raw materials is not preferable. Moreover, this method has a problem of using a larger amount of solvent.

As another method for producing polyester and polyester carbonate, a melt polycondensation method by a transesterification reaction is known. For example, a method of dephenolizing diphenyl carbonate and / or diphenyl dicarboxylate and diols is known. Further, as a method for producing a polyester, a method of deacetic acid-polymerizing a dicarboxylic acid and a diol in the presence of acetic anhydride is also known. These methods use no solvent,
Although it has the feature that it does not use halogen-based raw materials, it is difficult to obtain a high molecular weight product, and since the reaction is carried out at high temperature, the coloring and physical properties (for example, mechanical properties and fluidity) of the obtained polymer decrease. It has the problem of happening.
Furthermore, the former dephenolization method has a problem that the cost of the raw material diphenyl ester is high,
The latter deacetic acid method has a problem that the reactor is corroded by acetic anhydride or acetic acid produced as a by-product. Such a problem is inevitable in principle.

As a means for solving the problems of the melt polycondensation method, for example, a method for producing a polyester and a polyester carbonate has been proposed in which an aromatic polycarbonate and a dicarboxylic acid ester are transesterified in a molten state. (US Pat. No. 43606)
No. 48). In this method, the cost of raw materials used is low, and in principle, there is no active hydrogen (derived from phenol, carboxylic acid, etc.) in the raw materials, products, and by-products, so that there is no problem of corrosion.

However, it has been found that the polymer obtained by the above method has a high degree of coloring. Therefore, when it is used as a molding material that requires transparency, it is feared that it will be a fatal problem in appearance.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and an object thereof is to overcome the drawbacks of the above conventional methods for producing polyesters and polyester carbonates, and to eliminate halogens. It is an object of the present invention to commercially provide a method for producing polyesters and polyester carbonates which can be produced at low cost without using inclusions and solvents and have a low degree of coloring.

[0008]

DISCLOSURE OF THE INVENTION As a result of intensive studies, the inventors of the present invention have reacted at least one polycarbonate with at least one diester of a dicarboxylic acid in the presence of an esterification or transesterification catalyst. A method for producing polyester and polyester carbonate, wherein the reaction temperature is 300 ° C. throughout the above reaction.
The present invention has been completed by finding that the following manufacturing method can solve the above problems. The manufacturing method of the present invention is novel, and thereby the above-mentioned object is achieved.

That is, the present invention is a process for producing a polyester and a polyester carbonate, which comprises reacting at least one polycarbonate with a diester of at least one dicarboxylic acid in the presence of an esterification or transesterification catalyst, The present invention relates to a production method in which the reaction temperature is 300 ° C. or lower throughout the reaction.

In a preferred embodiment, the polycarbonate is represented by the following general formula (I):

[0011]

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In the formula, R ¹ is a divalent hydrocarbon group having 1 to 20 carbon atoms; at least a part of hydrogen atoms of the hydrocarbon group is a halogen atom, a hydrocarbon group, an alkoxy group, and a phenoxy group. A divalent hydrocarbon group having 1 to 20 carbon atoms, which is substituted with at least one selected from the group consisting of groups; or a R ² —X—R ³ group (wherein R ² and R ³ Is a divalent aromatic hydrocarbon group,
Each hydrogen atom of the aromatic ring may be independently substituted with a halogen atom, a hydrocarbon group, an alkoxy group or a phenoxy group, and X is a single bond, -O-,-
S -, - SO -, - SO 2 -, - CO-, and is selected from the group consisting of a hydrocarbon radical having from 1 to 20 carbon atoms)
And a is an integer from 1 to 5000.

In a preferred embodiment, the diester of dicarboxylic acid is represented by the following general formula (II):

[0014]

Embedded image

In the formula, R ⁴ is a divalent hydrocarbon group having 1 to 20 carbon atoms; at least a part of the hydrogen atoms of the hydrocarbon group is a halogen atom, a hydrocarbon group, an alkoxy group, or a phenoxy group. A divalent hydrocarbon group having 1 to 20 carbon atoms substituted with at least one selected from the group consisting of; and R ⁵ is 1 to 20
It is a hydrocarbon group having 4 carbon atoms.

In a preferred embodiment, the polycarbonate is 2,2-bis (4-hydroxyphenyl).
Propane polycarbonate.

In a preferred embodiment, the diester of dicarboxylic acid is selected from the group consisting of dimethyl terephthalate, dimethyl isophthalate, and dimethyl naphthalene-2,6-dicarboxylate.

In a preferred embodiment, the esterification or transesterification catalyst is a tin compound.

In a preferred embodiment, the esterification or transesterification catalyst is lithium, sodium,
A metal selected from the group consisting of potassium, magnesium, calcium, barium, strontium, zinc, cadmium, titanium, zirconium, tin, antimony, lead, manganese, and cobalt, acetate, carbonate, borate,
It is at least one selected from the group consisting of oxides, hydroxides, hydrides, alcoholates, and phenolates.

In a preferred embodiment, the esterification or transesterification catalyst is used in an amount of 0.0001 to 1 part by weight based on 100 parts by weight of the produced polyester or polyester carbonate.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.

The polycarbonate used in the present invention is
It is preferably represented by the general formula (I). Where R
¹ is a divalent hydrocarbon group having 1 to 20 carbon atoms; at least a part of hydrogen atoms of the hydrocarbon group is selected from the group consisting of a halogen atom, a hydrocarbon group, an alkoxy group, and a phenoxy group. A divalent hydrocarbon group having 1 to 20 carbon atoms, which is substituted with at least one of R ² -X-R ³ (wherein R ² and R ^2
3 is a divalent aromatic hydrocarbon group, each hydrogen atom of the aromatic ring may be independently substituted with a halogen atom, a hydrocarbon group, an alkoxy group or a phenoxy group, and X Is a single bond, -O-, -S-, -SO-,
Selected from the group consisting of —SO ₂ —, —CO—, and hydrocarbon groups having 1 to 20 carbon atoms); and a is an integer from 1 to 5000.

Specific examples of the above polycarbonate include:
The polycarbonate derived from the diol shown below is mentioned. For example, 2,2-bis (4-hydroxyphenyl) propane (also known as bisphenol A), bis (4-
Hydroxyphenyl) methane, bis (4-hydroxy-)
3,5-dimethylphenyl) methane, bis (4-hydroxy-3,5-dichlorophenyl) methane, 1,1-bis (4-hydroxyphenyl) cyclohexylmethane,
1,1-bis (4-hydroxyphenyl) ethane, 1,
1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1-bis (4-hydroxyphenyl) -3,
3,5-Trimethylcyclohexane (also known as bisphenol TMC), 4,4'-dihydroxydiphenyl ether, bis (4-hydroxy-3,5-dimethylphenyl) ether, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxy) -3,5-dimethylphenyl) sulfone, 4,4'-dihydroxybenzophenone, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, tetrabromobisphenol A,
Tetrachlorobisphenol A, dihydroxydiphenyl, hydroquinone, resorcinol, dihydroxynaphthalene, dihydroxyanthracene, phenolphthalein, fluorescein, 2,2'-dihydroxy-
Polycarbonates derived from aromatic diols such as 1,1-dinaphthylmethane and 4,4′-dihydroxydinaphthyl, and ethylene glycol, propylene glycol, tetramethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, 1,3- For aliphatic diols such as propanediol, 1,2-propanediol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, 1,6-hexanediol, and 1,10-decanediol. The polycarbonate derived from is mentioned. These polycarbonates may be used alone or in combination.

Among the polycarbonates used in the present invention, the polycarbonate derived from bisphenol A is preferable.

The diester of dicarboxylic acid used in the present invention is preferably represented by the above general formula (II). Here, R ⁴ is a divalent hydrocarbon group having 1 to 20 carbon atoms; at least a part of hydrogen atoms of the hydrocarbon group is
A divalent hydrocarbon group having 1 to 20 carbon atoms substituted with at least one selected from the group consisting of a halogen atom, a hydrocarbon group, an alkoxy group, and a phenoxy group; and R ⁵ is , A hydrocarbon group having 1 to 20 carbon atoms.

Specific examples of the diester of the above dicarboxylic acid include those shown below. For example, terephthalic acid, methoxyterephthalic acid, ethoxyterephthalic acid, fluoroterephthalic acid, chloroterephthalic acid, methylterephthalic acid, isophthalic acid, phthalic acid, methoxyisophthalic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylmethane-3,3 '-Dicarboxylic acid, diphenyl ether-4,4'-dicarboxylic acid, diphenyl-4,4'-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid Aromatic dicarboxylic acids such as acids, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, aliphatic dicarboxylic acids such as 3-methylazelaic acid, 1, 4-cyclohexanedicarboxylic acid, 1,3-silane Clohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,5-decahydronaphthalenedicarboxylic acid, 2,6-decahydronaphthalenedicarboxylic acid, 2,
Alicyclic dicarboxylic acids such as 7-decahydronaphthalenedicarboxylic acid, such as dimethyl, diethyl, dipropyl,
Examples thereof include dibutyl, dicyclohexyl and diphenyl ester. These dicarboxylic acid diesters may be used alone or in combination.

Among the dicarboxylic acid diesters used in the present invention, dimethyl terephthalate, dimethyl isophthalate and dimethyl naphthalene-2,6-dicarboxylate are preferred.

As the catalyst used in the present invention, known esterification or transesterification catalysts can be used. As these catalysts, alkali metals such as lithium, sodium and potassium, alkaline earth metals such as magnesium, calcium, barium and strontium, zinc,
Examples thereof include acetates, carbonates, borates, oxides, hydroxides, hydrides, alcoholates, and phenolates of metals such as cadmium, titanium, zirconium, tin, antimony, lead, manganese, and cobalt. These esterification or transesterification catalysts may be used alone or in combination.

Of these, tin compounds are preferred,
For example, stannous acyl, stannous tetraacyl tin, dibutyltin oxide, dibutyltin diacetate, dibutyltin laurate, dimethyltin maleate, tin dioctanoate, tin tetraacetate, stannous chloride,
Stannic chloride, stannous acetate, trichlorobutyltin,
Examples include dichlorodibutyltin, stannous oxide, and stannic oxide.

The amount of these catalysts used is not particularly limited, but is preferably 0.0001 to 1 with respect to 100 parts by weight of the produced polymer in view of the balance between reactivity and physical properties (for example, coloring and hydrolysis resistance). 0.0 parts by weight, more preferably 0.0005 to 0.1 parts by weight, is used. When the amount of the catalyst used is less than 0.0001 part by weight, the reaction does not proceed sufficiently, and when it is more than 1.0 part by weight, the resulting polymer is severely colored and the physical properties such as hydrolysis resistance are deteriorated. .

In addition to these catalysts, other additives such as stabilizers, pigments, dyes, optical brighteners, nucleating agents, polymerization accelerators, fillers and reinforcing materials (eg glass fiber, carbon fiber)
It is also possible to add such as at the time of polymerization or to the produced polymer.

In the present invention, it is preferable to carry out the reaction in two different steps. What is a different two-step process?
(1) a step of melting and heating a polycarbonate and a diester of a dicarboxylic acid under normal pressure to cause a depolymerization reaction and a transesterification reaction to form an oligomer; and (2) by further transesterification under reduced pressure. The process of producing high molecular weight polyester and polyester carbonate,
The process and the latter are the second process.

The present invention is characterized in that the reaction temperature is 300 ° C. or lower throughout the above reaction. The reaction temperature in each step is not particularly limited as long as it is 300 ° C. or lower, but the reaction temperature in the first step is preferably 200 to 28.
0 degreeC, More preferably, it is 240-260 degreeC. The reaction temperature in the second step is preferably 250 to 290 ° C.
In the whole reaction, when the reaction temperature is higher than 300 ° C., the polymer product is strongly colored. Furthermore, the first
When the reaction temperature of the step is lower than 200 ° C and when the reaction temperature of the second step is lower than 250 ° C, the reaction does not proceed sufficiently. However, the present invention is not limited to the reaction in the above two-step process as long as the reaction temperature of the entire reaction process is 300 ° C. or lower.

In the production method of the present invention, the amount of each reaction component used and the reaction conditions are appropriately adjusted to
The carbonate moieties can be reacted completely or incompletely. As a result, it becomes possible to selectively produce the desired polyester or polyester carbonate. That is, in the production method of the present invention, when a large amount of the diester of dicarboxylic acid is used with respect to the dicarbonate of polycarbonate and / or diol, the carbonate portion completely reacts, and as a result, the carbonate portion disappears to form a polyester. To do. On the other hand, when the amount of the diester of the dicarboxylic acid is smaller than the amount of the dicarbonate of the polycarbonate and / or the diol, the carbonate portion does not completely react, and as a result, the carbonate portion remains, so that the polyester carbonate is formed. To do.

In order to produce the polyester obtained by the production method of the present invention, a ratio such that the number of moles of diester of dicarboxylic acid is not less than the number of moles of repeating units of polycarbonate (and / or dicarbonate of diol). Can be used in. On the other hand, in order to produce the polyester carbonate obtained by the production method of the present invention, the number of moles of the diester of dicarboxylic acid is
It may be used in a proportion such that it is less than the number of moles of repeating units of polycarbonate (and / or dicarbonate of diol). Further, the molecular weight of the polyester or polyester carbonate obtained by the production method of the present invention can be adjusted by a known method such as the amount of catalyst.

In the present invention, suitable cosolvents such as diphenyl ether, biphenyl, substituted cyclohexane, decahydronaphthalene, 1,2,4,5-
Tetramethylbenzene may be used. Alternatively, a non-solvent that is not compatible with the resulting polymer may be used, such as poly (fluorinated alkylene oxide).

The polyester and polyester carbonate obtained by the production method of the present invention may be pelletized (chipted) and then molded, or may be directly molded into a desired shape using an extruder or the like. is there. Furthermore, polyester and polyester carbonate obtained by the production method of the present invention, other known polymers, for example, polyethylene, polypropylene,
It is also possible to blend with one or more of polystyrene, polymethylmethacrylate, polyamide, polycarbonate, polyester, polyphenylene oxide, polysulfone and the like.

The polyester and polyester carbonate obtained by the production method of the present invention can be widely used for producing shaped articles, fibers, filaments, films and the like. The polyester and polyester carbonate obtained by the production method of the present invention have high heat resistance, toughness, hydrolysis resistance, creep resistance, and the like, and therefore, fields requiring these physical properties, for example, the home appliance field and the lighting field. , And especially in the automotive field.

[0039]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited to the following examples, but various modifications can be made without departing from the scope of the invention. .

The properties of the polymer were measured according to the methods described below.

(1) Weight average molecular weight (Mw) of polymer: Measured by gel permeation chromatography (GPC) method. Chloroform was used as a mobile phase and a polymer concentration was 2 m using a Waters 510 type GPC system.
It was measured in g / ml at a column temperature of 35 ° C. Weight average molecular weight was calculated using polystyrene as a standard sample.

(2) Coloring degree of polymer Using a Z-Σ80 color difference meter manufactured by Nippon Denshoku Industries Co., Ltd., JIS
Based on K7103, the yellowness index (YI) was measured by the transmission method. As the test piece, a molded product having a thickness of 1/8 inch was used.

(Example 1) A polycarbonate reactor (Panlite L-1250W, Mv, Teijin Chemicals Co., Ltd.) was placed in a stainless steel reactor having an internal volume of 14 L equipped with a stirring blade, a nitrogen inlet, a cooling pipe, and a distillation outlet. = 25000) 1271g
(5.0 mol), 582 g of dimethyl terephthalate (3
Mol), 582 g (3 mol) of dimethyl isophthalate,
After charging 0.585 g (1.67 mmol) of dibutyltin diacetate and purging with nitrogen, 4 under the condition of nitrogen flow.
The mixture was heated at 240 ° C./minute to 240 ° C. (this temperature is referred to as T ₁ ). Then, the rotation of the stirring blade was started, and the dimethyl carbonate produced at the same temperature was refluxed for 1 hour. Subsequently, dimethyl carbonate was removed from the distillation port at 1 ° C./min at 260 ° C. (this temperature is T ₂ ) over 1 hour. Then, the reaction system was slowly depressurized (1 torr in 30 minutes), and at the same time, 290 ° C at 0.5 ° C / minute.
The temperature was raised to (this temperature is referred to as T ₃ ) and kept as it was for 2 hours. After the stirring was stopped, the pressure was returned to atmospheric pressure with nitrogen, and then the reaction mixture was taken out to obtain a polymer. The obtained polymer was dissolved in methylene chloride and poured into a large amount of hexane to reprecipitate the polymer for purification.

The IR spectrum of the obtained polymer is shown in FIG.
Shown in The material polycarbonate is 1775 cm
^-1 absorption of C = O stretching vibration derived from a carbonate bond is observed, but such absorption is not observed in the obtained polymer, and instead C = O derived from an ester bond is detected.
Absorption of stretching vibration was confirmed at 1740 cm ^-1 . These results showed that the polymer obtained was a polyester.

The obtained polymer was subjected to the above tests (1) and (2) to evaluate the characteristics. The results are shown in Table 1.

(Comparative Example 1) T ₁ was set to 280 ° C. and T ₂ was set to 3
The same procedure as in Example 1 was carried out except that 00 ° C. and T ₃ were 320 ° C.

The physical properties of the obtained polymer are shown in Table 1.

(Example 2) T ₁ was set to 240 ° C. and T ₂ was set to 2
Example 1 was repeated except that the temperature was 40 ° C and the T ₃ was 280 ° C.

The physical properties of the obtained polymer are shown in Table 1.

(Example 3) T ₁ was set to 260 ° C. and T ₂ was set to 2
Example 1 was repeated except that the temperature was 60 ° C and the T ₃ was 300 ° C.

The physical properties of the obtained polymer are shown in Table 1.

Example 4 Without using dimethyl isophthalate, the amount of dimethyl terephthalate used was 777 g.
The same procedure as in Example 1 was carried out except that (4 mol) was used.

The IR spectrum of the obtained polymer is shown in FIG.
Shown in The resulting polymer was observed the absorption of C = O stretching vibration derived from the carbonate linkage 1775 cm ^-1, and absorption of C = O stretching vibration derived from the ester bond at 1740 cm ^-1. With these results,
The polymer obtained was shown to be a polyester carbonate.

The physical properties of the obtained polymer are shown in Table 1.

[0055]

[Table 1]

From the results shown in Table 1 above, by setting the reaction temperature to 300 ° C. or lower throughout the reaction for producing the polymer, the obtained polyester and polyester carbonate have a reaction temperature higher than 300 ° C. It can be seen that the degree of coloring is low.

[0057]

According to the production method of the present invention, polyester and polyester carbonate having a low degree of coloring can be produced by a simple and inexpensive method.

[Brief description of drawings]

FIG. 1 is an IR spectrum chart of the polyester obtained in Example 1.

2 is an IR spectrum chart of the polyester carbonate obtained in Example 4. FIG.

Claims (8)

[Claims] 1. A process for producing polyesters and polyester carbonates, which comprises reacting at least one polycarbonate with at least one diester of a dicarboxylic acid in the presence of an esterification or transesterification catalyst, the entire reaction comprising: To a reaction temperature of 300 ° C. or lower. 2. The production method according to claim 1, wherein the polycarbonate is represented by the following general formula (I): In the formula, R ¹ is a divalent hydrocarbon group having 1 to 20 carbon atoms; at least a part of hydrogen atoms of the hydrocarbon group is
A divalent hydrocarbon group having 1 to 20 carbon atoms substituted with at least one selected from the group consisting of a halogen atom, a hydrocarbon group, an alkoxy group, and a phenoxy group; or R ² —X— R ³ group (wherein R ² and R ³ are divalent aromatic hydrocarbon groups, and the hydrogen atoms of the aromatic ring are each independently a halogen atom, a hydrocarbon group, an alkoxy group, or a phenoxy group). And X is a single bond, —O—, —S—, —SO—,
Selected from the group consisting of —SO ₂ —, —CO—, and hydrocarbon groups having 1 to 20 carbon atoms); and a is an integer from 1 to 5000. 3. The production method according to claim 1, wherein the diester of the dicarboxylic acid is represented by the following general formula (II): In the formula, R ⁴ is a divalent hydrocarbon group having 1 to 20 carbon atoms; at least a part of hydrogen atoms of the hydrocarbon group is
A divalent hydrocarbon group having 1 to 20 carbon atoms substituted with at least one selected from the group consisting of a halogen atom, a hydrocarbon group, an alkoxy group, and a phenoxy group; and R ⁵ is , A hydrocarbon group having 1 to 20 carbon atoms. 4. The method according to claim 1, wherein the polycarbonate is 2,2-bis (4-hydroxyphenyl) propane polycarbonate. 5. The method according to claim 1, wherein the diester of dicarboxylic acid is selected from the group consisting of dimethyl terephthalate, dimethyl isophthalate, and dimethyl naphthalene-2,6-dicarboxylate. . 6. The production method according to claim 1, wherein the esterification or transesterification catalyst is a tin-based compound. 7. The esterification or transesterification catalyst is lithium, sodium, potassium, magnesium,
Calcium, barium, strontium, zinc, cadmium, titanium, zirconium, tin, antimony, lead,
A metal selected from the group consisting of manganese and cobalt, which is at least one selected from the group consisting of acetate, carbonate, borate, oxide, hydroxide, hydride, alcoholate, and phenolate. The manufacturing method according to any one of 1 to 5. 8. The method according to claim 1, wherein the esterification or transesterification catalyst is used in an amount of 0.0001 to 1 part by weight based on 100 parts by weight of the produced polyester or polyester carbonate. Production method.