KR20050117872A - Novel manufacturing method of polyester copolymer - Google Patents

Abstract

The reaction time is short, the reaction efficiency and productivity are excellent, the reaction equipment is simple, the physical properties of the produced polyester copolymer is excellent, the amount of catalyst used is small, and the bis (hydr) manufactured by depolymerizing the waste of polyester copolymer The use of oxyalkyl) esters results in a novel process for producing polyester copolymers that is environmentally friendly. The method for producing the polyester copolymer is characterized by polymerizing a dicarboxylic acid component and a diol component in the presence of a macrocyclic polyester oligomer. Here, the macrocyclic polyester oligomer is prepared by reacting a bis (hydroxyalkyl) ester and a dicarboxylic acid chloride in the presence of an unhindered amine, and the bis (hydroxyalkyl) ester is depolymerized a polyester polymer. It is preferable to manufacture, and it is preferable that the usage-amount of the said macrocyclic polyester oligomer is 5 to 45 weight% with respect to all the polyester copolymerization raw materials.

Description

Novel manufacturing method of polyester copolymer

The present invention relates to a novel method for producing a polyester copolymer, and more particularly to a novel method for producing a polyester copolymer using a macro cyclic polyester oligomer as a reaction raw material.

Polyester copolymers have excellent physical properties and are widely used in plastic molding products, containers, sheets, films, fibers, filaments, and engineering plastics. It can be prepared by esterification and condensation polymerization of a monomer having a dihydroxy end group (diol component) and a monomer having a dicarboxyl end group (dicarboxylic acid component). In order to improve the efficiency of the polyester copolymer production reaction, a variety of methods have been researched and developed in the past, and a representative one of them is a method of improving the reaction efficiency by improving the catalyst of the reaction. For example, there is a method of producing using an active antimony catalyst, a titanium catalyst, or a germanium catalyst, or a complex catalyst using the catalyst together, and recently, a polyester copolymer using an aluminum catalyst The manufacturing method is introduced. However, the production method for improving the polymerization activity using these organic or organic-inorganic complex catalysts, since a large amount of catalyst must be used to reduce the reaction time, it may adversely affect the physical properties of the copolymer, the main component of the catalyst There is a problem that the metal is not environmentally friendly.

Accordingly, an object of the present invention is to provide a novel method for producing a polyester copolymer, which has a short reaction time, excellent reaction efficiency and reaction productivity, simple reaction equipment, and excellent physical properties of the produced polyester copolymer. will be.

Another object of the present invention is to provide a novel method for producing an environmentally friendly polyester copolymer because the amount of catalyst used is small and bis (hydroxyalkyl) esters prepared by depolymerization of the polyester copolymer waste are used.

In order to achieve the above object, the present invention provides a method for producing a polyester copolymer characterized in that the dicarboxylic acid component and the diol component are polymerized in the presence of a macrocyclic polyester oligomer.

Here, the macrocyclic polyester oligomer is prepared by reacting a bis (hydroxyalkyl) ester with a dicarboxylic acid chloride in the presence of an unhindered amine, and the bis (hydroxyalkyl). The ester is preferably produced by depolymerizing a polyester polymer. It is preferable that the usage-amount of the said macrocyclic polyester oligomer is 0.1 to 45 weight% with respect to all the polyester copolymerization raw materials.

Hereinafter, the present invention will be described in detail.

The method for producing a polyester copolymer according to the present invention uses a dicarboxylic acid component, a diol component and a macrocyclic polyester oligomer as a reaction raw material.

As the dicarboxylic acid component used in the present invention, dicarboxylic acid components usually used for the production of polyester copolymers can be used, but are not limited to aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid and phthalic acid. And aliphatic dicarboxylic acids such as sebacic acid, lower alkyls thereof, preferably methyl, ethyl and esterified derivatives may be used, and trivalent or higher polyhydric carboxylic acids such as trimellitic acid and pyromellitic acid may be used if necessary. It may include. As the diol component used in the present invention, diol components commonly used in the production of polyester copolymers can be used, and without limitation, aliphatic diols such as ethylene glycol, propylene glycol and 1,4-butanediol can be used. If necessary, trivalent or higher polyhydric alcohols such as aromatic diol, sorbitol, 1,2,3,6-hexatetrol may be included.

The macrocyclic polyester oligomer used in the present invention includes a repeating unit represented by the following formula (1).

In Formula 1, X is an alkylene radical or oxyalkylene radical having 2 to 6 carbon atoms, Y is an aliphatic, aromatic or alicyclic radical, preferably a phenylene radical, and the microcyclic polyester used in the present invention. In the oligomer, the number of repeating units is 1 to 50, preferably 2 to 20.

Such macrocyclic poly (alkylene dicarboxylate) oligomers have been used as polymerization raw materials of branched polyesters (US Pat. No. 5,389,719) and US Pat. No. 5,231,161. As disclosed in bis (4-hydroxybutyl) terephthalate (bis (4-) in the presence of unhindered amines or in the presence of tertiary amine mixtures such as unhindered amines and triethylamine. It may be prepared by reacting a bis (hydroxyalkly) ester such as hydroxybutyl) terephthalate and a dicarboxylic acid chloride such as terephthaloyl chloride.

The bis (hydroxyalkyl) ester used in the preparation of the polyester oligomer is preferably prepared through a depolymerization process which is a chemical recycling process of the polyester polymer. As the polyester used for such depolymerization, polyester flakes obtained by pulverizing a polyester waste produced during a polyester polymer molding, a polyester molding process or a polyester polymerization can be used. In order to prepare a bis (hydroxyalkyl) ester, first, pulverized polyester particles are put into a reactor, and an excess of glycol-based compounds such as ethylene glycol (ethyleneglycol) is added (about 100 to 300 parts by weight based on 100 parts by weight of polyester pulverized particles). ) And reacted under pressure. At this time, if necessary, a certain amount of depolymerization catalyst may be introduced into the reactor. As such depolymerization catalyst, various known catalysts such as antimony, titanium, germanium, etc. may be used, and a titanium catalyst is more preferable. Pressurization conditions for the depolymerization of the polyester depends on the durability of the reactor, but it is preferable to pressurize as much as possible within the allowable range of the reactor, for example, it can be carried out at a pressure of 1.5 to 2.5kgf / cm ² . In addition, the depolymerization may be carried out at a general polyester polymerization temperature, for example, it may be carried out in the range of about 250 to 320 ℃.

In this way, the bis (hydroxyalkyl) ester prepared through the depolymerization process is added to an organic solvent such as methylene chloride to form a solution, and separately mixed with an organic solvent such as chlorobenzene and the like. Prepare monochloride solution. Next, to the solution prepared by adding a tertiary amine such as triethylamine and unhindered amine such as 1,4-diazabicyclo octane to methylene chloride, the two solutions prepared above were added for about 30 to 40 minutes. While simultaneously stirring at room temperature, the mixture is stirred for an additional 5 to 10 minutes, filtered and dried to prepare a macrocyclic polyester oligomer. The microcyclic polyester oligomer may be synthesized as a linear polyester polymer by supporting a monomer including a repeating unit of Formula 1 on a solid carrier, as described in US Pat. No. 5,756,644.

In order to manufacture the polyester copolymer according to the present invention, the macrocyclic polyester oligomer is added during the production process of a conventional polyester copolymer. The amount of the macrocyclic polyester oligomer used is preferably 0.1 to 45% by weight, and 5 to 45% by weight based on the total amount of polyester copolymer raw materials (dicarboxylic acid component, diol component and microcyclic polyester oligomer). % Is more preferable, and 10-20 weight% is the most preferable. If the amount of the macrocyclic polyester oligomer is less than 0.1% by weight, there is a slight problem that the degree of polymerization of the copolymer by the polyester oligomer has a slight problem. If the content exceeds 45% by weight, the main reaction is not an ester reaction or a polycondensation reaction, It becomes a polymerization reaction and the cost of production increases as the cost rises.

The method and timing of the macrocyclic polyester oligomer according to the present invention may be added at the initial stage of the super-middle or condensation polymerization reaction of the ester reaction, preferably at a separate time, and may be added separately. It is further more preferable that the ratio of the initial stage of the super-medium group of the silver ester reaction and the initial stage of the polycondensation reaction are 30:70 to 40:60 by weight ratio, respectively. The super middle and middle stages of the esterification reaction are when the dicarboxylic acid component such as terephthalic acid and the diol component such as ethylene glycol are prepared as a slurry and subjected to heat and pressure reaction in the reactor, and then the byproduct water starts to flow through the condenser. In the reaction system, water required for the ring-opening reaction of the microcyclic polyester oligomer is present as a reaction by-product, and the reaction is activated between a predetermined amount of terephthalic acid and ethylene glycol. In the early stage of the polycondensation reaction, the cyclic ester oligomer is added to the esterification reaction, and stirred sufficiently for 20 to 30 minutes, followed by applying a vacuum to the reactor. The reaction can be carried out at conventional temperatures of the process of polymerizing the polyester copolymer. For example, the ester reaction may be performed at 265 to 275 ° C, and the polycondensation reaction may be performed at 275 to 295 ° C. In addition, if necessary, conventional polymerization catalysts such as antimony catalyst, germanium catalyst, titanium catalyst, etc. may be used within the range of 0 to 300 ppm according to the required physical properties of the final copolymer, preferably cyclic ester. An amount of 30 to 60 wt% less than the amount used in the conventional reaction in which the polyester oligomer is not added may be used. The atmosphere of the reaction is a nitrogen cycle or vacuum, and is selected according to the design of the reactor or the degree of polymerization desired, and the reaction time may also be variously controlled according to the designed polymerization apparatus and the desired degree of polymerization.

The macrocyclic polyester oligomer, which is used in the method for producing a polyester copolymer according to the present invention, becomes a ring-opened ionized oligomer, thereby acting as a catalyst for activating the condensation polymerization reaction as well as the ester reaction. Helps to form chains to increase the degree of polymerization in a short time. In the production method according to the present invention, in the production method of a conventional polyester copolymer, by introducing a macrocyclic polyester oligomer, by introducing an addition reaction mechanism in which the oligomer is ring-opened to become an ionized oligomer, a rapid increase in the degree of polymerization Since the reaction mechanism is used to induce, the final product of the same degree of polymerization can be prepared within a short reaction time using a conventional polyester polymerization equipment, thereby improving reaction efficiency and reaction productivity. On the other hand, in the existing reaction system, if necessary, it can be added to the ester reaction or preferably in the middle of the transesterification reaction, and the polymerization time can be shortened by adding to the initial stage of the polycondensation reaction to contribute to the increase in the polymerization degree. In this case, the main reaction mechanism is an increase in the degree of polymerization by the addition reaction, the initial degree of polymerization during the polymerization reaction is increased by the addition reaction of the macrocyclic ester oligomer, and the increase in the degree of post-polymerization depends on the polycondensation reaction.

Hereinafter, the present invention will be described in more detail with reference to specific examples and comparative examples. The following examples are intended to illustrate the present invention more specifically, but the scope of the present invention is not limited by the following examples.

Example 1

end. Preparation of Macrocyclic Polyester Oligomers

First, the polyester molded product was washed well, crushed finely with a grinder to prepare pulverized particles, and then 50 g of pulverized particles and 100 g of ethylene glycol were introduced into the reactor. After adding 0.5 g of a titanium catalyst, tetrabutyl titanate, to the reactor, depolymerization was performed while stirring for 3 hours under a temperature of 290 ° C. and a pressure of 2.0 kgf / cm ² . After the depolymerization reaction was completed, bis (hydroxyalkyl) ester was prepared by discharging the remaining ethylene glycol through a distillation column. V) a solution prepared by adding 10 g of the prepared bis (hydroxyalkyl) ester to 30 ml of methylene chloride and ii) a solution made by adding 7 g of terephthaloyl chloride to 30 ml of chlorobenzene, and then mixing the mixed solution with 80 g of triethylamine. And 250 ml of methylene chloride solvent comprising 300 mg of 1,4-diazabicyclo octane with stirring for about 30 minutes. At this time, the temperature of the reactor was maintained at room temperature. After further stirring for about 10 minutes, filtered and the filtered reaction was washed with aqueous hydrochloric acid solution and pure water, and then the reaction was filtered again using a phase separation room, and the solvent was removed by vacuum drying to macro cyclic Polyester oligomers were prepared.

I. Preparation of Polyethylene Terephthalate

200 g of terephthalic acid and 90 g of ethylene glycol were added to the three-necked circular flask reactor and stirred well to prepare a slurry. The slurry was stirred at 30 rpm while maintaining the internal temperature of 265 ° C. using a heating mantle. Then, nitrogen was introduced into the reactor to circulate nitrogen by allowing a certain amount of nitrogen to flow under pressurization of about 0.2 bar into the nitrogen atmosphere. At the time when the byproduct water began to come out through the condenser, 40 g of the polyester oligomer prepared above was added to the reactor and the reaction was continued while maintaining 265 ° C. The ester reaction was completed by using the end point of the reaction when water, which was a byproduct of the reaction, was no longer present.

After the ester reaction was completed, 100 ppm of the antimony catalyst dissolved in ethylene glycol was added to the reactor, 0.1torr vacuum was slowly applied, and the condensation polymerization reaction was performed for 1 hour while maintaining the reactor internal temperature at 280 ° C. The polycondensation reaction was carried out while controlling the output of the stirrer in consideration of the decrease in the stirring speed according to the rise of the viscosity of the reactant as the reaction time elapsed, while maintaining the stirring speed at a constant 30rpm. After the condensation polymerization was completed, a slightly yellowish reactant was obtained, and the prepared reactant was quenched in a bath containing cold water to prepare polyethylene terephthalate. After drying the sample of the prepared polyethylene terephthalate well, the molecular weight was measured by gel permeation chromatography (GPC) is shown in Table 1 below.

Example 2

200 g of terephthalic acid and 90 g of ethylene glycol were added to the three-necked circular flask reactor and stirred well to prepare a slurry. The slurry was stirred at 30 rpm while maintaining the internal temperature of 265 ° C. using a heating mantle. Then, nitrogen was introduced into the reactor to circulate nitrogen by allowing a certain amount of nitrogen to flow under pressurization of about 0.2 bar into the nitrogen atmosphere. At the time when the byproduct water began to come out through the condenser, 20 g of polyester oligomer was added to the reactor and the reaction was continued while maintaining 265 ° C. The ester reaction was completed by using the end point of the reaction when water, which was a byproduct of the reaction, was no longer present.

After the ester reaction was completed, 20 g of polyester oligomer and 100 ppm of an antimony catalyst dissolved in ethylene glycol were added to the reactor, and the condensation polymerization reaction was carried out for 1 hour while slowly applying 0.1torr vacuum and maintaining the reactor internal temperature at 280 ° C. Was performed. The polycondensation reaction was carried out while maintaining a constant stirring speed of 30rpm. After the condensation polymerization was completed, a slightly yellowish reactant was prepared, and the prepared reactant was quenched in a bath containing cold water to prepare polyethylene terephthalate. After drying the sample of the prepared polyethylene terephthalate well, the molecular weight was measured using GPC is shown in Table 1 below.

Example 3

200 g of terephthalic acid and 90 g of ethylene glycol were added to the three-necked circular flask reactor and stirred well to prepare a slurry. The slurry was stirred at 30 rpm while maintaining the internal temperature of 265 ° C. using a heating mantle. Then, nitrogen was introduced into the reactor to circulate nitrogen by allowing a certain amount of nitrogen to flow under pressurization of about 0.2 bar into the nitrogen atmosphere. The ester reaction was completed by using the end point of the reaction when water, which was a byproduct of the reaction, was no longer present.

After the ester reaction was completed, 40 g of polyester oligomer and 100 ppm of an antimony catalyst dissolved in ethylene glycol were added to the reactor, and 0.1 tor vacuum was slowly applied, and the condensation polymerization reaction was carried out for 1 hour while maintaining the reactor internal temperature at 280 ° C. Was performed. The polycondensation reaction was carried out while maintaining a constant stirring speed of 30rpm. After the condensation polymerization was completed, a slightly yellowish reactant was prepared, and the prepared reactant was quenched in a bath containing cold water to prepare polyethylene terephthalate. After drying the sample of the prepared polyethylene terephthalate well, the molecular weight was measured using GPC is shown in Table 1 below.

Comparative Example 1

200 g of terephthalic acid and 90 g of ethylene glycol were added to the three-necked circular flask reactor and stirred well to prepare a slurry. The slurry was stirred at 30 rpm while maintaining the internal temperature of 265 ° C. using a heating mantle. Then, nitrogen was introduced into the reactor to circulate nitrogen by allowing a certain amount of nitrogen to flow under pressurization of about 0.2 bar into the nitrogen atmosphere. The ester reaction was completed by using the end point of the reaction when water, which was a byproduct of the reaction, was no longer present.

After the ester reaction was completed, 100 ppm of the antimony catalyst dissolved in ethylene glycol was added to the reactor, and the condensation polymerization reaction was performed for 1 hour while gradually applying 0.1torr vacuum and maintaining the reactor internal temperature at 280 ° C. The polycondensation reaction was carried out while maintaining a constant stirring speed of 30rpm. After the condensation polymerization was completed, a slightly yellowish reactant was prepared, and the prepared reactant was quenched in a bath containing cold water to prepare polyethylene terephthalate. After drying the sample of the prepared polyethylene terephthalate well, the molecular weight was measured using GPC is shown in Table 1 below.

Comparative Example 2 Preparation of Polyethylene Terephthalate

Polyethylene terephthalate was prepared in the same manner as in Comparative Example 1, except that 200 ppm of an antimony catalyst was used. After drying the sample of the prepared polyethylene terephthalate well, the molecular weight was measured using GPC is shown in Table 1 below.

Ester reaction Condensation polymerization Response time (hours) Mw Mw / Mn Usage of Macrocyclic Polyester Oligomer (g) Use of catalyst Usage of Macrocyclic Polyester Oligomer (g) Antimony Catalyst Usage (ppm) Example 1 40 X X 100 2.1 45,000 3.2 Example 2 20 X 20 100 4.3 56,000 2.8 Example 3 X X 40 100 8.3 58,000 2.3 Comparative Example 1 X X X 100 8.5 35,000 3.9 Comparative Example 2 X X X 200 8.5 52,000 3.0

As shown in Table 1, in the reaction completion time of Examples 1 to 3, and Comparative Examples 1 and 2, it can be seen that the reaction time is shortened by the addition of the macrocyclic polyester oligomer. In addition, in the condensation-polymerization reaction (reaction time is the same as 1 hour) of Examples 1-3, the addition of the macrocyclic polyester oligomer to the polymerization reaction rate is carried out by putting polyester which is a final product into the weight average molecular weight of a copolymer. You can see that to speed up. In addition, as can be seen in Example 2 and Comparative Example 2, the polymer having a larger weight average molecular weight by adding a macrocyclic polyester oligomer, even though the amount of the antimony-based catalyst in the condensation polymerization reaction is 1/2 It can be seen that can be prepared. On the other hand, as the preferred timing and method of the macrocyclic polyester oligomer, as can be seen from the results of Examples 1 to 3, in Example 2, the ester reaction time is short and the weight average molecular weight of the final product is relatively Since it is large, it turns out that it is preferable to divide into ester reaction and polycondensation reaction, and to input.

The novel method for producing a polyester copolymer according to the present invention has the advantages of short reaction time, excellent reaction efficiency and reaction productivity, and simple reaction equipment. In addition, the production method of the polyester copolymer according to the present invention has an advantage that it can be used in various applications, such as plastic molded products, containers, sheets, films, fibers due to the excellent physical properties of the prepared polyester copolymer. In addition, the novel production method of the polyester copolymer according to the present invention has the advantage of using less catalyst and environmentally friendly because it uses bis (hydroxyalkyl) ester prepared by depolymerizing the waste of the polyester copolymer.

Claims (7)

A method for producing a polyester copolymer characterized by polymerizing a dicarboxylic acid component and a diol component in the presence of a macrocyclic polyester oligomer. The method of claim 1, wherein the macrocyclic polyester oligomer comprises a repeating unit represented by the following formula (1). [Formula 1] In Formula 1, X is an alkylene radical or oxyalkylene radical having 2 to 6 carbon atoms, Y is an aliphatic, aromatic or alicyclic radical, and in the macrocyclic polyester oligomer, the number of repeating units is 1 To 50. The method of claim 1, wherein the macrocyclic polyester oligomer is prepared by reacting bis (hydroxyalkyl) ester with dicarboxylic acid chloride in the presence of an unhindered amine. The method of claim 3, wherein the bis (hydroxyalkyl) ester is prepared by depolymerizing a polyester polymer. The method of claim 1, wherein the amount of the macrocyclic polyester oligomer is 0.1 to 45% by weight based on the total polyester copolymer raw material. The method according to claim 1, wherein the macrocyclic polyester oligomer is introduced into the ester reaction super middle, the condensation polymerization initial stage, or the ester reaction super middle and condensation polymerization initial stage. The method according to claim 1, wherein the macrocyclic polyester oligomer is divided into a ratio of 30:70 to 40:60 by weight in the initial stage of esterification and initial polymerization.