JPH10330465A - Continuous production of polyester and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide both a continuous method for producing a polyester by which the rate of reaction and the quality of the polyester can remarkably be improved to remarkably reduce the equipment cost, the equipment space can remarkably be reduced and foreign materials are hardly caused, and an apparatus therefor. SOLUTION: This continuous apparatus for producing a polyester is obtained by connecting a transesterification reactional chamber or an esterification reactional chamber 2 to a polycondensation reactional chamber 3 in this order in upper and lower parts and blowing an inert gas into the reactional chambers 2 and 3 with feed pipes 11 which are feeding means for the inert gas, in relation to a continuous method and the apparatus for producing the polyester from a dicarboxylic acid consisting essentially of an aromatic dicarboxylic acid, an alicyclic dicarboxylic acid or an aliphatic dicarboxylic acid and an ester- forming derivative thereof and a diol component according to a continuous melt polymerization method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a dicarboxylic acid containing an aromatic dicarboxylic acid as a main component, an alicyclic dicarboxylic acid,
The present invention also relates to a method and apparatus for continuously producing a polyester from an aliphatic dicarboxylic acid or an ester-forming derivative thereof and a diol component by a continuous melt polymerization method.

[0002]

2. Description of the Related Art Polyesters represented by polyethylene terephthalate and polybutylene terephthalate have been widely used in various applications because of their excellent physical and chemical properties. In particular, fibers, films, and other molded articles are widely used in clothing, industrial fibers such as tire cords, engineering plastics, and the like because of their excellent mechanical properties such as strength and elastic modulus and heat resistance.

[0003] In general, polyesters used for such various uses are produced by a direct polymerization method or a transesterification method. Here, the former direct polymerization method is a method of producing a polyester precursor by directly esterifying an acid component and a diol component, and then subjecting the polyester precursor to polycondensation under reduced pressure. On the other hand, the latter transesterification method is a method of producing a polyester precursor by subjecting a lower alkyl ester of an acid component and a diol to a transesterification reaction, and then subjecting the polyester precursor to polycondensation under reduced pressure.

Conventionally, the above-mentioned polymerization of polyester has been often carried out by a batch method. However, in order to take advantage of scale and to produce polyester at low cost, switching to a continuous method has been promoted. The merits such as improvement of yield and quality, uniformity of polymerization degree and improvement of operability by adopting the continuous method are extremely large.

In general, many continuous polyester production methods are carried out by a process in which a plurality of transesterification or esterification reaction tanks and a polycondensation reaction tank are combined. For example, a raw material is supplied to a transesterification reaction tank or an esterification reaction tank to generate a monomer, and the obtained monomer is supplied to an initial polycondensation reaction tank and reacted under reduced pressure to produce a low polymer. Is produced, and this low polymer is supplied to a polycondensation reaction tank under reduced pressure to obtain an intermediate polymer and a high polymer.

However, most of the above-mentioned reaction equipment has a complicated structure. In particular, a polycondensation reaction tank is provided with an extremely complicated stirrer in order to stir the reactants to increase the evaporation area. However, these facilities require a large amount of equipment and energy costs, and also require a space for installing a plurality of reaction facilities and their auxiliary facilities. is there.

[0007] Therefore, a production method using a simplified reaction apparatus has been proposed in order to reduce the production cost of the above-mentioned reaction equipment. For example, Japanese Patent Publication No. 42-24191 proposes a method and an apparatus for continuously producing a high-molecular-weight polymer by means of a chamber connected to a reaction chamber, an evaporation chamber, and a finishing chamber in the vertical direction. ing. However, in the method and the apparatus, the surface of the gas phase in each chamber is not sufficiently renewed and the atmosphere is not in an inert gas atmosphere. There is a problem that becomes. Furthermore, in the finishing room, it is necessary to maintain a high degree of vacuum of 1 mmHg, and in a large-scale production facility, the size of the vacuum device needs to be increased.

Japanese Patent Application Laid-Open No. 8-31107 proposes an apparatus for continuously producing a polycondensation polymer in which an upper transesterification tower and a lower prepolymerization tower are combined into an integrated structure. ing. That is, the apparatus comprises an ester exchange tank for generating an oligomer by a transesterification reaction from a mixture of raw materials, and an initial polymerization tank for polycondensing the oligomer to produce an intermediate polymer, which are vertically arranged in series in a vertical direction. This is a continuous production apparatus for polycondensation polymers, which is an integrated structure. However, in the continuous production apparatus, only the initial polymerization is performed, and another production apparatus is required to obtain a high polymer which is valuable as a product. In addition, the surface of the gas phase is not sufficiently renewed,
Moreover, since the atmosphere is not an inert gas atmosphere, there is a problem that the polymer scattered and adhered in the apparatus stays, causes thermal deterioration, and becomes a foreign substance.

[0009]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to solve the above problems by injecting an inert gas into a polyester production apparatus and causing the reaction to proceed. It is an object of the present invention to provide a continuous production apparatus for polyester which can significantly improve the quality of polyester and has less foreign matter.

[0010] Further, by using a reactor having an integral structure, the manufacturing cost of the equipment can be greatly reduced, and the installation space can be greatly reduced as compared with the conventional manufacturing method. An object of the present invention is to provide a continuous production apparatus for polyester, which enables production of polyester by one production apparatus.

[0011]

Means for Solving the Problems Here, the continuous production method of the polyester of the present invention is as follows. (Claim 1) A dicarboxylic acid, an alicyclic dicarboxylic acid, an aliphatic dicarboxylic acid or a dicarboxylic acid containing an aromatic dicarboxylic acid as a main component. In a method of continuously producing a polyester by continuously melt-polymerizing a raw material comprising an ester-forming derivative of and a diol component, the raw material is obtained by subjecting the raw material to a transesterification reaction or an esterification reaction in an upper ester reaction chamber. A continuous production method of polyester, characterized in that the reaction product obtained is supplied to a lower polycondensation reaction chamber to cause a polycondensation reaction, and an inert gas is blown into these reaction chambers (Claim 2). 2. A method for continuous production of polyester according to claim 1, wherein the polyester polymer is obtained under a pressure of (3), wherein an inert gas is blown into the liquid phase of the reactant. Writing method of continuously producing a polyester according to claim 1, and (4.) Continuous process for producing a polyester according to claim 1, wherein the blowing inert gas containing the diol component are provided.

Further, the continuous production apparatus of the polyester of the present invention comprises (claim 5) a dicarboxylic acid, an alicyclic dicarboxylic acid, an aliphatic dicarboxylic acid or an ester-forming derivative thereof, containing an aromatic dicarboxylic acid as a main component. , A continuous production apparatus for polyester that continuously melt-polymerizes a diol component, the continuous production apparatus comprises a reaction apparatus comprising an ester exchange reaction chamber or an esterification reaction chamber at the top, and a polycondensation reaction chamber at the bottom. An apparatus for continuous production of polyester including means for supplying inert gas into a reactor is provided.

[0013]

Embodiments of the present invention will be described below. As the polyester produced by the method and apparatus of the present invention, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate,
Examples thereof include polybutylene naphthalate and polybutylene isophthalate. Examples of the dicarboxylic acid containing an aromatic dicarboxylic acid component as a main component or its ester-forming derivative include terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, and 1,5.
-Naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and / or their lower alkyl esters (the alkyl group usually has 1 to 4 carbon atoms) and the like. Further, examples of the alicyclic dicarboxylic acid component or its ester-forming derivative include cyclohexanedicarboxylic acid, and the like, and examples of the aliphatic dicarboxylic acid or its ester-forming derivative include adipic acid, sebacic acid,
Suberic acid and the like, preferably terephthalic acid,
Examples include 1,4-naphthalenedicarboxylic acid, isophthalic acid, and dimethyl terephthalate. These aromatic dicarboxylic acid component, alicyclic dicarboxylic acid component and aliphatic dicarboxylic acid component may be used alone or in combination of two or more.

Next, diol components include ethylene glycol, neopentyl glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5- Examples thereof include pentadiol, 1,6-hexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, polyalkylene glycol, and propylene glycol. Of these, ethylene glycol, 1,4-butanediol and diethylene glycol are preferred. These glycol components may be used alone or in combination of two or more.

The polyester may be copolymerized with a compound such as a trifunctional or higher polyfunctional compound such as trimellitic acid, pyromellitic acid or glycerol, or a monofunctional compound such as benzoic acid or phenyl isocyanate.

The production of the polyester in the present invention may be carried out in the presence or absence of a catalyst. When a catalyst is used, a known catalyst can be used. For example, antimony compounds, manganese compounds, titanium compounds, tin compounds, zinc compounds, magnesium compounds and the like are used. The position and method for supplying such a catalyst are not particularly limited. If necessary, other commonly used thermoplastic resins,
One or more of additives, inorganic fillers, organic fillers, etc. may be added to the reactor of the present invention as it is or together with the diol component, or may be directly kneaded by a molding machine, an extruder, a mixer, etc. at the outlet of the reactor. These can be kneaded by remelting after mixing or pelletizing. Here, examples of the other thermoplastic resin include a polyester-based resin, a polyamide-based resin, a polystyrene-based resin, polycarbonate, and polyacetal. As additives, known antioxidants, antistatic agents, brominated polycarbonates, flame retardants such as brominated epoxy compounds,
Examples include flame retardant aids such as antimony trioxide and antimony pentoxide, plasticizers, lubricants, release agents, coloring agents, and crystal nucleating agents. Further, as the inorganic filler, glass fiber, talc, mica, glass flakes, carbon fiber, silica, alumina fiber, milled glass fiber, clay,
Examples thereof include metal compounds such as carbon black, kaolin, titanium oxide, iron oxide, antimony oxide, and alumina, and alkali metal compounds such as potassium and sodium. Examples of the organic filler include aromatic polyester fibers and liquid crystalline polyester fibers.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. FIG. 1 is a flow diagram (schematic cross-sectional view) illustrating a polyester manufacturing apparatus for carrying out the present invention.

In the figure, reference numeral 1 denotes an integrated cylindrical continuous manufacturing apparatus to which the method of the present invention is applied, and the apparatus 1 includes a heating device (not shown) for heating a reactant to a desired temperature. ) Is provided. In addition, as the heating device, a known heating device such as a heating device in which a jacket chamber is formed around the body of the cylindrical continuous manufacturing apparatus 1 and a heating means such as a heating medium is passed through the jacket chamber can be used.

Reference numeral 2 denotes a transesterification reaction chamber or an esterification reaction chamber (hereinafter sometimes simply referred to as "ester reaction chamber"), and 3 denotes a polycondensation comprising one or more vertically connected chambers. It is a reaction chamber. Here, the ester reaction chamber 2 and the polycondensation reaction chamber 3 are vertically connected as shown. 4 is a shelf having a bent groove, 5 and 6
Denotes a raw material supply pipe, 7 denotes a flow control valve, 8 denotes a perforated plate, and 9 denotes an inert gas supply pipe.

First, the ester reaction chamber 2 will be described. In the ester reaction chamber 2, raw materials are continuously supplied to the shelf 4 from the raw material supply pipes 5 and 6. At the end of the shelf 4, a level adjusting member such as a weir described in Japanese Patent Publication No. 35-7380 is provided to keep the reactant at a constant liquid level. For this reason, the reactants spill over the shelves 4 provided in multiple stages while spilling over the shelves in a desired amount while successively flowing down, and reacting while securing the residence time necessary for the transesterification reaction or esterification reaction. In addition, a liquid level meter (not shown) is provided on the lowermost shelf 4 so that the liquid level is always detected and controlled so that the liquid level becomes optimum. Then, by passing through a perforated plate 8 provided below the flow control valve 7 and having a perforated plate structure as described in, for example, Japanese Patent Publication No. 36-13815, the reactant becomes a filament or a film. And the evaporation of by-products is accelerated during this time. At this time, the heated inert gas is blown into the gas phase of the ester reaction chamber 2 from the inert gas supply pipe 9 provided as a means for supplying the inert gas.

Next, the polycondensation reaction chamber 3 will be described.
The illustrated polycondensation reaction chamber 3 is provided with a ring-shaped pipe 10 having a plurality of holes for blowing an inert gas, and is inertized from the inner wall surface of the continuous manufacturing apparatus 1 to the ring-shaped pipe 10. A pipe 11 for supplying gas is connected. At this time, the inert gas is supplied from the inert gas supply pipe 12, heated to a desired temperature by the heater 13, and then blown into each polycondensation reaction chamber 3.

The bottom portion 14 of each polycondensation reaction chamber 3 has a conical wall surface opened in a funnel shape upward, and has a structure in which a reactant continuously flowing down from the upper portion is received by the bottom portion 14. . Therefore, a liquid pool portion, that is, a liquid phase portion, of the reactant is formed by the cylindrical inner wall surface of the continuous manufacturing apparatus 1 and the conical wall surface of the bottom portion 14. The degree of opening of the conical surface can be changed according to the reaction conditions. Thus, the polycondensation reaction proceeds at a remarkably high speed due to the stirring effect of the inert gas and the effect of increasing the area of the gas-liquid contact portion while sequentially moving the reactants through one or more reaction chambers.

Although the polycondensation reaction chambers are connected by a pipe, the flow control valve 7 and the perforated plate 8 can be installed at the connection part as needed. The flow control valve 7 and a liquid level meter (not shown) for keeping the amount of the reactant retained in each polycondensation reaction chamber 3 constant.
And the liquid amount can be controlled to an arbitrary value in accordance with the liquid level detected by the liquid level meter.

In the ester reaction chamber 2 and the polycondensation reaction chamber 3 configured as described above, the vapor by-product produced as a result of the reaction, together with the inert gas, is desirably discharged from the outlet and the reaction chamber. Are exhausted from the openings 15 and 16 which also serve as exhaust ports for maintaining the pressure. Then, finally, the polyester obtained by causing a desired polycondensation reaction from the lowermost liquid distilling section 17 is continuously discharged from the discharge port 18 by the gear pump 19.

In the method for producing a polyester by the continuous production method of the present invention, the pressure at the time of the reaction is not particularly limited, and the present invention is also applicable to a polymerization reaction under vacuum, normal pressure or a pressure higher than normal pressure. Although possible, it is preferable that the pressure is normal pressure or higher. For this reason, when the reaction is performed under reduced pressure in each reaction chamber as in the conventional method, it is usually necessary to provide a steam ejector or the like as a bleeding device. However, as in the method of the present invention, a normal pressure or a pressure higher than the normal pressure is required. Such a device is not always necessary when the reaction is performed under the following conditions. Therefore, equipment cost can be further reduced by omitting the bleeding device.

In the present invention, the inert gas may be blown into the liquid phase and / or gas phase of the continuous production apparatus 1, but in order to obtain a higher reaction rate. Is preferably a liquid phase part rather than a gas phase part. Here, the “liquid phase portion” refers to “the inside of the reactant staying in the continuous production apparatus” or “the inside of the reactant staying in the transport pipe”, and particularly about the blowing method. It is not limited. Therefore, for example, a plurality of supply pipes may be provided so as to supply the inert gas to a plurality of locations in the liquid phase portion.Also, a static or dynamic mixer may be provided to react the reactant with the inert gas. Can be used. The blowing speed of the inert gas and the flow rate thereof may be within a range in which the continuous operation can be stably performed. The inert gas blowing speed and the flow rate may be adjusted so as to obtain the desired quality of the polyester, such as the intrinsic viscosity and the carboxyl end group concentration. Preferably, the flow rate of the active gas is adjusted by a valve or the like provided in the supply pipe. The blowing of the inert gas may be continuous and / or intermittent. Further, it is preferable that the inert gas to be introduced is heated and introduced by the heater 13 or the like, whereby heat is uniformly applied to the reactant from the blown inert gas, thereby supplying heat necessary for the reaction. can do. However, when the temperature of the inert gas is higher than a desired temperature, it is preferable to supply the gas after cooling it with a cooler or the like.

Further, it is also a preferable embodiment that an inert gas containing a diol component is introduced into the continuous production apparatus 1 in advance. By supplying the inert gas together with the diol component in this manner, an increase in the substantial reaction molar ratio and good dispersion of the inert gas can be expected, and the effect of accelerating the reaction is increased. Here, the term "inert gas containing a diol component or the like in advance" refers to an inert gas containing a diol component or the like by-produced during the reaction in another polycondensation reaction chamber,
Alternatively, it refers to a mixture of a diol component and an inert gas before being supplied to the continuous production apparatus 1.

Next, the inert gas of the present invention is preferably a gas which does not adversely affect the reaction and is a gas at the reaction temperature in the polymerization reaction chamber. Examples of such an inert gas include N ₂ , Ar and He. Etc. can be exemplified. Above all,
Nitrogen is particularly desirable because of its easy availability and low cost advantages. It is needless to say that such an inert gas is preferably introduced not only into the liquid phase of the reactor but also into the gas phase.

[0029] The polyester finally obtained as described above is continuously supplied to the spinning process, and continuously mixed with the above-mentioned thermoplastic resin, additives, inorganic fillers, organic fillers and the like. After mixing or reacting with a kneading device or a static mixer, the fiber can be made into a fiber by spinning, or can be made into a thin film by supplying to a film forming process. Also,
Once pelletized in a granulation step or the like, it can be sent to a fiberization step, a thinning step, a resin molding step, or the like.

Further, the finally obtained polyester is
It can be pelletized in a granulation step or the like, and can be further solidified under an inert gas atmosphere and / or under a high vacuum to further increase the degree of polymerization. Further, the polyester can be kneaded with a kneading device (for example, a vacuum device). , A biaxial vented extruder, etc.) to further increase the degree of polymerization.

If the polyester taken out through the gear pump contains a large amount of inert gas, the polyester may not be sufficiently pelletized in the granulation step or the like.
Prior to granulation, it is preferable to perform degassing by supplying the polyester to a degassing chamber equipped with a degassing outlet or a kneading device equipped with a vent. In this case, in addition to the inert gas, diol components, moisture, and the like can be removed at the same time. As means for continuously extracting polyester, means other than a gear pump, for example, a screw for taking out is installed at a polyester outlet of a continuous production apparatus, and the discharge apparatus may be integrated with the continuous production apparatus of the present invention. Good.

In the above polyester production process, the inert gas containing reaction by-products and the like is separated from the reaction by-products and the like by a known method such as a condenser, a filter, a combustion device, or an absorption device. Can be. In addition, the inert gas separated in this way can be circulated and used by being returned to the above-mentioned inert gas supply pipe by a circulation pump or the like. The advantage of this recycle use is that it can be operated with almost no reaction by-products being discharged to the outside of the system, so that the operation cost can be reduced, but it is not discharged out of the system as it is. Therefore, there is a great merit in terms of preventing environmental destruction and preventing pollution.

Further, in the polyester production process of the present invention, when the degree of polymerization of the polyester increases, the melt viscosity of the reactant increases, and the moving speed of the inert gas in the liquid phase decreases. For this reason, by reducing the liquid depth of the reactant in the polycondensation reaction chamber or by making it thinner,
It is preferred to reduce the distance traveled by the vaporous by-products, which results in higher polycondensation reaction rates.

As described above, the continuous production apparatus of the present invention can be heated by a known means.
For example, as a well-known means, the manufacturing apparatus outer shell may be directly heated by an electric heater, or the manufacturing apparatus outer shell may have a double jacket structure, and a suitable heating medium such as Dowsome liquid or A method of heating in the presence of steam or water vapor, a method of installing a tubular heat transfer surface in the reaction chamber, and circulating the reactants in the reaction chamber by convection can be appropriately adopted. In the heating, each reaction chamber and the reaction chamber may be further divided so that heating can be performed independently, or two or more reaction chambers can be integrally heated. Further, if necessary, it can be heated by passing through a heat exchanger provided separately from the continuous production apparatus of the present invention.

The number of polycondensation reaction chambers and the structure thereof are not particularly limited. However, in order to improve the dispersion of the inert gas in the polymerization reaction chamber, a stirring blade, a dispersion plate, a rectifying member, , Baffles, shelves, etc. can be provided as needed.

[0036]

EXAMPLE Using the continuous production apparatus shown in FIG. 1, dimethyl terephthalate (DMT) 300 kg / hr, ethylene glycol (EG) 202 parts / hr, manganese acetate 0.05 mole% / DMT (hereinafter referred to as mole percentage based on DMT) Is expressed as “mole% / DMT”), and zinc acetate is added at a concentration of 0.1%
It was continuously supplied to the ester reaction chamber 2 from the raw material supply pipe 5 together with the catalyst of 01 mole% / DMT. At this time, nitrogen heated countercurrently to the reactant via the inert gas supply pipe 9 is continuously transferred to the gas phase of the ester reaction chamber 2 at 0.5 Nm ³ / min.
I blew it. Then, methanol vapor by-produced in the transesterification reaction was exhausted from the exhaust port 15 in association with nitrogen blown in countercurrent. The exhaust gas also contains vapor of ethylene glycol (EG). After separating the vapor from methanol in the distillation column, the vapor is returned to the ester reaction chamber 2 again, and the ester chamber 2 separated by the shelf 4 is separated. The transesterification reaction proceeded under normal pressure or a reaction pressure higher than normal pressure while heating to a temperature of 150 to 260 ° C. in an inert gas atmosphere. Next, 0.1 mol% of phosphorous acid / DMT and 0.03 mol% of antimony trioxide / DMT as a polymerization catalyst were added to the obtained transesterification reaction product via a supply pipe 6. By passing through the plate 8, the reactant was made to flow into a plurality of filaments and flowed down to the upper chamber of the polycondensation reaction chamber 3.

At this time, the reaction temperature in the polycondensation reaction chamber 3 is 260 to 290 ° C. in the upper reaction chamber, the reaction pressure is normal pressure or higher than normal pressure, and the reaction pressure in the lower reaction chamber is 29 to 290 ° C.
0 ° C., and the reaction pressure was normal pressure or a pressure higher than normal pressure. Under these conditions, the reactants were allowed to flow down from the upper reaction chamber to the lower reaction chamber sequentially via the flow control valve 7 and the perforated plate 8. Nitrogen is supplied into the liquid phase from the ring-shaped pipe 10 via the supply pipe 11, and is supplied to the upper stage of the polycondensation reaction chamber 3.
0 nm ³ / min, proceeded by supplying the polycondensation reaction at 5 Nm ³ / min in the lower.

The vaporous by-products produced by the reaction are exhausted together with nitrogen from an exhaust port, separated from the reaction by-products and the like by a condenser, a filter, an absorption device, etc. (not shown), and supplied to an inert gas supply pipe. It was refluxed to 12 and used for circulation.
The EG discharged together with the nitrogen was recovered and reused as a raw material.

Further, the polyester finally obtained from the lower liquid reservoir 17 was continuously discharged from a discharge port 18 by a gear pump 19, and pelletized in a granulation step.

The obtained polyester has an intrinsic viscosity (calculated from a melt viscosity measured in orthochlorophenol at 25 ° C.) of 0.50, and a terminal carboxyl group concentration [A. Conix method (Makromol.
Chem, 26, 226, 1958) is 18 eq / T.
Met. Further, the obtained polyester was polyethylene terephthalate with less foreign matters because nitrogen was constantly present in the gas phase of the reaction chamber, and the reaction rate was much higher than that of the conventional method.

Comparative Example In the above example, the reaction was carried out in exactly the same manner as above except that no nitrogen was blown at all. However, not only the intrinsic viscosity of the polyester did not increase, but also the decomposition reaction was remarkable.

[0042]

According to the present invention, the reaction rate can be remarkably accelerated and the quality of the produced polyester can be improved as compared with the conventional production method and production apparatus by the continuous melt polymerization method. Further, the production cost of the reactor is greatly reduced, the continuous production of polyester is enabled by one production apparatus, and the installation space can be greatly reduced as compared with the conventional production method. In addition, polyesters with less generation of foreign substances can be produced, and are extremely useful as fibers, films, and other molding materials.

[Brief description of the drawings]

FIG. 1 is a schematic flow diagram (schematic cross-sectional view) of a continuous polymerization production apparatus for polyester for carrying out the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Continuous polymerization production apparatus of polyester 2 Transesterification reaction chamber 3 Polycondensation reaction chamber 5, 6 Raw material supply pipe 10 Ring pipe 11, 12 Inert gas supply pipe 13 Heater

Claims (5)

[Claims] A raw material comprising a dicarboxylic acid, an alicyclic dicarboxylic acid, or an aliphatic dicarboxylic acid, or an ester-forming derivative thereof, and a diol component, which are mainly composed of an aromatic dicarboxylic acid, and a diol component. In a continuous production method, the raw materials are subjected to a transesterification reaction or an esterification reaction in an upper ester reaction chamber, and then the obtained reactant is supplied to a lower polycondensation reaction chamber to cause a polycondensation reaction. A continuous method for producing polyester, wherein an inert gas is blown into these reaction chambers. 2. The continuous method for producing a polyester according to claim 1, wherein the polyester polymer is obtained under normal pressure or a pressure higher than normal pressure. 3. The continuous method for producing a polyester according to claim 1, wherein an inert gas is blown into the liquid phase of the reactant. 4. The continuous production method of a polyester according to claim 1, wherein an inert gas containing a diol component is blown. 5. A continuous production apparatus for polyester which continuously melt-polymerizes a dicarboxylic acid, an alicyclic dicarboxylic acid, or an aliphatic dicarboxylic acid or an ester-forming derivative thereof, and a diol component, mainly containing an aromatic dicarboxylic acid. The continuous production apparatus comprises a reaction apparatus comprising an ester exchange reaction chamber or an esterification reaction chamber at an upper part, a polycondensation reaction chamber at a lower part, and a means for continuously supplying polyester containing an inert gas supply means into the reaction apparatus. Manufacturing equipment.