JPS6050820B2 - Polyester manufacturing method - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing polyester.

More specifically, the present invention relates to an improved method for producing a copolyester comprising an aromatic oxycarboxylic acid component, an aromatic dicarboxylic acid component, and an aromatic dioxy compound component. --Polyethylene terephthalate is widely used industrially due to its excellent mechanical performance, but it cannot be said that it is sufficient in terms of Young's modulus and strength for some applications. , it is desired to develop polymers with high Young's modulus and high strength.

In recent years, it has been discovered that a molded article with a high Young's modulus and high strength can be obtained by melt-molding a specific wholly aromatic polyester (see Japanese Patent Publication No. 47-4787 Tan). On the other hand, as a method for producing such a wholly aromatic polyester, for example, p-oxybenzoic acid, diphenyl isophthalate, and hydroquinone (diphenyl isophthalate and hydroquinone obtained by reacting p-oxybenzoic acid and phenyl acetate in the presence of hydrochloric acid) are used. A method of polycondensing (the molar ratio of which is approximately 1:1) has been proposed. However, this method requires the use of highly corrosive compounds such as acetic acid and hydrochloric acid during the reaction, and therefore not only requires a reaction equipment made of corrosion-resistant materials, but also requires the use of highly corrosive compounds in the polycondensation reaction. This process requires a long time and is not suitable as an industrial method for producing wholly aromatic polyester. The present inventor has conducted extensive research into an industrially advantageous method for producing polyester that does not have such drawbacks, and has thus arrived at the present invention. That is, the present invention uses an aromatic oxycarboxylic acid and an aromatic/group dicarboxylic acid as bifunctional carboxylic acid components and an aromatic dioxy compound as a diol component when producing a polyester. Esterification reaction product of aromatic oxycarboxylic acid and aromatic monooxy compound and/or aromatic dioxy compound, (B) Esterification reaction product of aromatic dicarboxylic acid and aromatic monooxy compound and/or aromatic dioxy compound , (C) an aryl carbonate in an amount of 0.8 to 1.1 times the mole per carboxyl group contained in the prisoner component and (B) component, and (D) an aromatic dioxy compound as necessary, which is heated and reacted. This is a method for producing polyester.

To the method of the present invention? As an aromatic oxycarboxylic acid,
For example, in addition to p-oxybenzoic acid and m-oxybenzoic acid, 3-chloro-4-oxybenzoic acid, 3-methyl-4-oxybenzoic acid, 3-methoxy-4-oxybenzoic acid, 4-chloro-3-oxybenzoic acid Examples include oxybenzoic acid whose nucleus is substituted with a halogen atom, an alkyl group, or an alkoxy group such as an acid. Among these, p-oxybenzoic acid is particularly preferred. In the method of the present invention, aromatic dicarboxylic acids include, for example, terephthalic acid, isophthalic acid, 5-methylterephthalic acid, 4-methylisophthalic acid, naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl sulfone dicarboxylic acid, diphenol dicarboxylic acid, Oxyethanedicarboxylic acid, 5-chloroterephthalic acid, 4-chlorosophthalic acid and the like can be mentioned.

Among these aromatic dicarboxylic acids, terephthalic acid, isophthalic acid, and diphenooxyethane dicarboxylic acid are particularly preferred. In the method of the present invention, examples of the aromatic dioxy compound include compounds represented by the following formula.

HO-Ar[(0)MAr+-NOH[wherein A
r represents a divalent aromatic nucleus, M and n are O or the number of 1;

] The above aromatic nucleus (Ar) includes a substituted or unsubstituted aromatic nucleus, and more specifically includes a substituted or unsubstituted benzene nucleus or naphthalene nucleus.

Examples of specific aromatic dioxy compounds include: Hydroquinone, resonorescin, methylhydroquinone, chlorhydroquinone, methoxyhydroquinone, monoethoxyhydroquinone, chlorresorcinol, methylresorcinol, monoethoxyresorcinol, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 4
, 4″-dioxyether, 3,3″-dioxybiphenylene) L/, 3,3″-dimethyl-4,4″-dioxyphenyl, 4,4″-dioxydiphenyl ether, 3
, 3''-dioxydiphenyl ether, 3,3'-dichloro-4,4''-diphenyl ether, and the like. Among these, hydroquinone, 4,4''-dioxydiphenyl is particularly preferred. In the method of the present invention, the molar ratio of the aromatic oxycarboxylic acid component to the aromatic dicarboxylic acid component in the copolyester is preferably 10:100 to 10:100. in the range of 100:10, particularly preferably 25
:100 to 100:25, while preferably the content of the diol component in the copolyester is approximately equimolar to the content of the aromatic dicarboxylic acid and/or alicyclic dicarboxylic acid component.

In the method of the present invention, the aryl carbonate is an ester of the above-mentioned aromatic monooxy compound and/or aromatic dioxy compound and carbonic acid. Specifically, diphenyl carbonate. , ditolyl carbonate, di p-butylphenyl carbonate, di p-chlorophenyl carbonate, di β-naphthyl carbonate, bis p-hydroxyphenyl carbonate, bis m-hydroxyphenyl carbonate, bis p-(4-hydroxyphenyl) phenyl carbonate , phenyl trilyl carbonate,
Phenyl p-ku! phenyl carbonate, phenyl p
-Bidroxyphenyl carbonate, phenyl-4 hydroxy 3-chlorophenyl carbonate, tri-4
-Hydroxy-3-ethoxyphenyl carbonate,
In addition to monocarbonates such as, polycarbonates such as polym-phenylene carbonate can be mentioned. In the method of the present invention, component (4), an esterification reaction product of an aromatic oxycarboxylic acid and an aromatic monooxy compound and/or an aromatic dioxy compound (hereinafter abbreviated as A esterified product), refers to an aromatic oxycarboxylic acid and an aromatic It is a reaction mixture obtained by the direct esterification reaction described below with a group monooxy compound and/or an aromatic dioxy compound.

In addition, the esterification reaction product of an aromatic dicarboxylic acid and an aromatic monooxy compound and/or an aromatic dioxy compound (hereinafter abbreviated as B esterified product) as component (B) refers to the esterification reaction product of an aromatic dicarboxylic acid and an aromatic monooxy compound and/or an aromatic dioxy compound (hereinafter abbreviated as B esterified product). It is a reaction mixture obtained by the direct esterification reaction described below with/or an aromatic dioxy compound.

In the production of esterified product A or esterified product B, the aromatic monooxy compounds described below and/or the aromatic dioxy compounds described above can be used, but among these, it is preferable to use aromatic dioxy compounds.

When aromatic dioxy compound b is used, there is an advantage that esterified product A or esterified product B can be obtained in a relatively small amount in a short time. The aromatic monooxy compounds used in the production of esterified product A or esterified product B include those contained in the 1-aryl carbonate, such as phenol, cresol, p-ethylphenol, p-butylphenol, p-chlorophenol, m- It is an aromatic monooxy compound substituted with a lower alkyl group or a halogen atom such as chlorophenol, β-naphthol, etc. or unsubstituted with J.

In the esterification reaction to produce the A esterified product or the B esterified product, the hydroxyl group of the aromatic monooxy compound and/or the aromatic dioxy compound is is 1 times or more, preferably 1.1 to 4
The aromatic monooxy compound and/or aromatic dioxy compound is used in an amount of twice the molar amount, particularly preferably 1.2 to 2 times the molar amount.

The esterification reaction temperature is 150 to 330°C, preferably 180 to 300°C when producing esterified product A.
The temperature is particularly preferably 240 to 280°C, and the upper limit of the more preferred esterification temperature in producing the B ester may be changed depending on the type of difunctional carboxylic acid used. The upper limit temperature is 340°C when using an alicyclic dicarboxylic acid, and 360°C when using an aromatic dicarboxylic acid.
It is ℃. The esterification reaction time is usually 1 hour to 1 hour. The esterification reaction is carried out such that the esterification reaction rate is 50% or more, preferably 70% or more, particularly preferably 85% or more for esterified product A, although there is no particular restriction, and 70% or more for esterified product B. It is preferably 80% or more, particularly preferably 90% or more. Here, the esterification reaction rate is determined from the following formula.

((To VJ 1) <.kshi) Hoj! Teishare'-
In the esterification reaction to obtain the esterified product N'A or the esterified product B, a catalyst is not necessarily required, or preferably a catalyst is used.

Examples of catalysts include titanium, tin, lead, antimony,
Examples include metals such as bismuth, cerium, lanthanum, lithium, sodium, potassium, and zinc, and compounds containing these metals. More specifically, for example, titanium tetrabutoxide, titanyl oxalate, stannous acetate, lead oxide, lead acetate, antimony, antimony trioxide, antimony pentoxide, bismuth trioxide, cerium acetate, lanthanum oxide, lithium acetate, Examples include sodium metal, potassium benzoate, and zinc acetate.
The amount of these catalysts used is 0.00% relative to the carboxylic acid component such as the aromatic oxycarboxylic acid or aromatic dicarboxylic acid.
005-0.5 mol%, preferably 0.001-0.1
It is mole%. In the method of the present invention, the aromatic oxycarboxylic acid or A esterified product of component (4) is reacted with the B esterified product of component (B) and the aryl carbonate of component (C).

Since the aryl carbonate also reacts with the carboxyl group contained in the esterified product B, the aryl carbonate is added in an amount of 0.8 to 0.1 mole, preferably approximately 1 mole, per carboxyl group contained in the carrier component and component (B). It is preferable to add 1 to the reaction system so as to make a molar amount. The reaction of the aromatic oxycarboxylic acid or the esterified product A with the esterified product B and the aryl carbonate is carried out at a concentration of 180 to 330 aC1, preferably 200 to 300'C1, particularly preferably 220
The reaction is carried out at ~260°C until the generation of carbon dioxide gas produced by the reaction is substantially completed.

The reaction time is suitably 1 to 6 hours, and preferably a catalyst is used. The same catalyst as in the esterification reaction was used for the carboxylic acid component at a rate of 0.0% as in the case of the esterification reaction.
It can be used in a range of 0.05 to 0.5 mol%. In the method of the present invention, polyester is produced by using an aromatic oxycarboxylic acid and a B ester, or an A ester and a B ester.
The reaction is carried out in such a manner that an aryl carbonate is added to the esterified product, and if necessary, the aromatic dioxy compound is added as a diol component and the mixture is heated and condensed.

Here, the amount Y (number of moles) of the aromatic dioxy compound that needs to be added before the thermal condensation is represented by the following formula (1), [where X.

, YO represent the number of moles of aromatic dicarboxylic acid and the number of moles of aromatic dioxy compound (including aromatic dioxy compound in aryl carbonates) used during the esterification reaction, and Y is zero or more. be. ] Particularly preferably, it is represented by the following formula (2).

[However, X.

, YO, and Buddha are the same as the above definition.゛-゛If the amount used is too small, it will be difficult to obtain a polyester with a sufficiently high degree of polymerization even if the next polycondensation time is prolonged, and if it is too large, the polycondensation time will become longer, which is undesirable. . In the method of the present invention, polyester is produced by distilling off aromatic dioxy compounds and/or aromatic monooxy compounds produced by the polycondensation reaction out of the reaction system.

This polycondensation reaction is preferably carried out at 250 to 400°C, particularly preferably 300 to 360°C, and even more preferably 310 to 360°C.
The temperature is up to 350C, and the reaction pressure is 760 to 0.001 H.
gl is preferably 10 to 0.01 Hg and 2. When the reaction is carried out in this manner, the main chain of the polyester does not contain carbonate bonds, so substantially no gas is generated during melt molding of the polyester, which is preferable. The polymerization reaction is carried out in a molten state, but may be carried out in a solid phase if necessary. In addition, in the production of the above polyester, after the direct esterification reaction and before the completion of the polymerization, a small proportion of a dioxy compound represented by the following formula may be added as necessary to reduce excess aromatic dioxy compound and/or triaromatic monooxy A copolyester can also be obtained by conducting a polymerization reaction while distilling the compound out of the reaction system.

[However, in the formula, k is a divalent aromatic nucleus, R and R2 are lower alkyl groups having 1 to 6 carbon atoms, and may be bonded to each other.

] Specific examples of dioxy compounds represented by the above formula are:
2,2-bis(4-hydroxyphenylpropane, 2,
2-bis(4-hydroxyphenyl)butane, 1,1-
Bis(4-hydroxyphenyl)cyclohexane and the like are exemplified.

According to the method of the present invention, highly corrosive compounds such as hydrochloric acid and acetic acid are not produced as by-products during the polymerization reaction, and
To produce a highly polymerized polyester which is industrially extremely advantageous since the decomposition of the raw aromatic oxycarboxylic acid during copolyester production is small (for example, 10% or less), and both the direct esterification time and the polycondensation time can be shortened. be able to.

The method of the present invention will be explained below with reference to Examples.

In addition, "parts" in the examples mean "parts by weight."

In addition, the amount of free carboxyl groups was determined by the Konics method (Ma
krOMolecularChem,? , 226 (19
58)), and the amount of ester groups was determined by saponifying the sample with an alcoholic solution of caustic soda and then back titrating the excess alkali with sulfuric acid. Example 1 (1) Production of B esterification reaction product of isophthalic acid and methyl hydroquinone. 3318 parts of isophthalic acid, 372 CB of methyl hydroquinone, and 2 parts of stannous acetate were placed in an esterification pot and heated at 300°C under a nitrogen atmosphere. The mixture was heated for 4 hours, and water produced as a result of the esterification reaction was removed from the reaction system.

The esterification reaction rate of the obtained B esterification reaction product was 80
It was %. (2) Production of A esterification reaction product of p-oxybenzoic acid and methylhydroquinone, 410 parts of p-oxybenzoic acid, 27 (4) parts of methylhydroquinone, and 4 parts of stannous acetate are placed in an esterification pot, Water produced as a result of the esterification reaction was removed from the reaction system by heating at 250° C. for 4 hours under a nitrogen atmosphere.

The esterification reaction rate of the obtained A esterification reaction product was 65
It was %. 3) Production of copolyester, A esterified product, B esterified product and 2988 parts of ditolyl carbonate (corresponding to 0.9 mol based on the carboxyl group in A esterified product and B esterified product)
were charged into a polymerization pot, reacted at 250 to 280°C for 1 hour at normal pressure, and then heated to 320°C, which required 6 powders and 0.3
=Hg, and polymerization was continued for 6 cycles.

The obtained polymer was dissolved in p-chlorophenol and
The intrinsic viscosity was determined to be 1.35 at a polymer concentration of 0.5 g/De. The amount of phenol that was produced as a by-product during the production of this copolyester was determined using gas chromatography for the distillate, and it was found to be 7% based on the charged p-oxybenzoic acid component. p- in the polymer
This was consistent with the results of determining the oxybenzoic acid content. Example 2 (1) Production of B esterification reaction product of isophthalic acid and methylhydroquinone, directly esterifying isophthalic acid and methylhydroquinone in exactly the same manner as in Example 1 to obtain an esterification reaction rate of 80%. A B esterification reaction product was obtained.

(2) Production of copolyester, 41 parts of p-oxybenzoic acid and 8227 parts of ditolyl carbonate are added to the above esterified product B (1 mole based on p-oxybenzoic acid and the carboxyl group in the esterified product A). ) was added thereto, and the reaction was continued at 250 C for 1 hour and at 2600 C for 2 hours under normal pressure, during which time the cresol produced by the reaction was distilled off.

Then, the obtained reaction mixture was transferred to a polymerization pot and
After reacting at 0°C for 1 hour at normal pressure, the temperature was raised to 320'C and it took 60 minutes to achieve 0.3T! The polymerization was continued at $LHg for 6 minutes. The obtained polymer was dissolved in p-chlorophenol at 50'C and the polymer concentration was 0.5 g.
The intrinsic viscosity was determined as /De and found to be 1.30.

The amount of phenol produced as a by-product during the production of this copolyester was determined by gas chromatography using a distillate, and it was found to be 6% based on the charged p-oxybenzoic acid component. Example 3 1) Production of B esterified product of isophthalic acid and phenol 3,318 parts of isophthalic acid, 65 parts of phenol, and 2 parts of stannous acetate were placed in an esterification pot, and 6.
The pressure was increased to 5k9/d (gauge pressure) and the reaction was carried out at 280 to 290°C for 6 hours, and the water produced was removed from the reaction system.

The esterification reaction rate of the obtained esterified product B was 83%. 2) Production of A esterified product of p-oxybenzoic acid and phenol 41 parts of p-oxybenzoic acid, 9870 parts of phenol, and 4 parts of stannous acetate were placed in an esterification pot, and nitrogen gas was added to the mixture at a rate of 6.5 kg/d. (gauge pressure) and reacted for 6 hours, and the produced water was removed from the system.

The esterification reaction rate of the obtained esterified product A was 77%. 3) Production of copolyester The total amount of esterified product A and esterified product B, 2931 parts of diphenyl carbonate, and 66 parts of hydroquinone were charged into a polymerization pot, and reacted at 250 to 280'C under normal pressure for 1 hour, and then heated to 320°C. It takes 60 minutes to raise the temperature to 0.
The polymerization was conducted at 3W0!1Hg for 6 minutes.

Claims (1)

[Claims] 1. When producing a polyester containing an aromatic oxycarboxylic acid and an aromatic dicarboxylic acid as bifunctional carboxylic acid components and an aromatic dioxy compound as a diol component, (
A) aromatic oxycarboxylic acid, or esterification reaction product of aromatic oxycarboxylic acid and aromatic monooxy compound and/or aromatic dioxy compound, (B) aromatic dicarboxylic acid and aromatic monooxy compound and/or aromatic compound Esterification reaction product with dioxy compound, (C) 0.8 to 1 per carboxyl group contained in component (A) and component (B)
．． A method for producing polyester, which comprises heating and reacting 1 mole of aryl carbonate and (D) an aromatic dioxy compound if necessary.