KR20140060138A - Catalyst composition for preparing polyester and method for preparing polyester using the same - Google Patents

Abstract

The present invention relates to a catalyst composition for preparing polyester and a method for preparing polyester by using the same, and more specifically, to a catalyst composition comprising an aluminum-based compound and a complex metal oxide; and a method for producing polyester by using the same. The catalyst composition of the present invention is environmentally friendly, does not occur yellowing in a polycondensation process, and has the commercialization level of catalytic activity.

Description

TECHNICAL FIELD The present invention relates to a catalyst composition for preparing polyester and a method for preparing the same,

The present invention relates to a catalyst composition for producing polyester, and a process for producing polyester using the same. More particularly, the present invention relates to a catalyst composition for producing polyester comprising an aluminum compound and a composite metal oxide, and a method for producing polyester using the same.

BACKGROUND OF THE INVENTION Polyesters are excellent in mechanical properties and chemical properties and can be used for various applications such as drinking water containers and medical applications, food packaging materials, food containers, sheets, films, . Typical examples are polyethylene terephthalate, which is widely used for excellent physical and chemical properties and dimensional stability, and is mainly composed of antimony acetate (Sb (OAc) ₂ ) and antimony oxide Sb ₂ O ₃ ) catalyst.

However, in the case of a product made of an antimony catalyst, a large amount of antimony should be used in the polymerization process, and since the metal itself is toxic, antimony is released when it is used for a long period of time, ( Anal . Bioanal. Chem . 2006, 385, 821). In recent years, it has been reported that a large amount of antimony is produced in drinking water bottles, fruit juice bottles, and food packaging materials using antimony catalyst ( Environ . Sci . Technol ., 2007, 41, 1560) . Thus, in some developed countries, the use of antimony catalysts is being regulated or prohibited, and environmentally friendly catalysts are being developed to replace toxic metals such as antimony.

There have been proposed methods using a metal compound known as an environmentally friendly substance which is less toxic in vivo and capable of replacing a toxic antimony catalyst, as a polyester polymerization catalyst.

For example, International Patent Publication No. WO95 / 018839 discloses a catalyst for producing polyesters and copolyesters using TiO ₂ / SiO ₂ or TiO ₂ / ZrO ₂ co-oxidant coagulates. In Japanese Patent Application Laid-Open No. 2003-40991, TiO ₂ / Al ₂ O ₃ , TiO ₂ / SiO ₂ Or TiO ₂ / ZrO ₂ Or the like as a catalyst has been proposed.

However, the titanium compound catalyst itself has high activity, but causes the formation of a yellow colored polymer. Also, it has a problem of instability due to hydrolysis by reacting with water produced in the polycondensation process, and the viscosity is not significantly increased in solid phase polymerization. Due to such disadvantages, there is a problem that it is difficult to actually apply the titanium-based catalyst to commercialization although the titanium-based catalyst is substantially excellent in metal self-activity.

Therefore, development of a catalyst having high activity while preventing yellowing and pyrolysis for commercial application is still required.

It is an object of the present invention to solve the above problems, and an object of the present invention is to provide an eco-friendly polyester which is easy to synthesize with high catalytic activity, exhibits sufficient polycondensation activity even with a small amount, And to provide a catalyst composition which can be used for production.

It is also an object of the present invention to provide a process for producing a polyester using the catalyst composition.

In order to achieve the above object, the present invention provides a catalyst composition for polyester polymerization comprising a composite metal oxide containing titanium (Ti), aluminum (Al), and magnesium (Mg) .

The present invention also relates to a process for polymerizing a dicarboxylic acid component and a glycol component in the presence of a catalyst composition comprising a composite metal oxide containing titanium (Ti), aluminum (Al), and magnesium (Mg) And a method for producing the polyester.

The catalyst composition of the present invention is very useful as a catalyst composition for producing an environmentally friendly polyester by allowing esterification reaction and polyester polycondensation even in a small amount.

In addition, when the polyester is produced using the catalyst composition of the present invention, the activity of the aluminum-based compound is increased due to the increase of the catalytic activity, so that little thermal decomposition occurs, so that the yellowing phenomenon is relatively reduced and high viscosity can be maintained. In addition, catalyst compositions without fast reaction times, high intrinsic viscosities, inexpensive raw materials and toxicity can be usefully applied in commercial applications.

In addition, in the case of a polyester resin using the polyester obtained by the above-mentioned method for producing polyester, particularly polyethylene terephthalate, excellent physical properties such as color, transparency, viscosity and brightness can be applied to beverage and food- have.

The catalyst composition of the present invention includes a composite metal oxide including titanium (Ti), aluminum (Al), and magnesium (Mg) and an aluminum compound.

The method for producing a polyester according to the present invention is a method for producing a polyester by reacting a dicarboxylic acid component and a dicarboxylic acid component in the presence of a catalyst composition comprising a composite metal oxide containing titanium (Ti), aluminum (Al), and magnesium (Mg) And polymerizing the glycol component.

Hereinafter, the catalyst composition of the present invention and the method for producing polyester using the same will be described in more detail.

Catalyst composition

The catalyst composition of the present invention includes a composite metal oxide including titanium (Ti), aluminum (Al), and magnesium (Mg) and an aluminum compound.

The catalyst composition of the present invention can be used in the polymerization of a polyester, and in particular, can be used as a catalyst in the production of polyethylene terephthalate.

The composite metal oxide contained in the catalyst composition of the present invention may be represented by the following formula (1) or (2).

[Chemical Formula 1]

(2)

In Formula 2, n is an integer of 2 to 20.

According to an embodiment of the present invention, the composite metal oxide may be a coprecipitate of a titanium alkoxide represented by the following formula (3), an aluminum alkoxide represented by the following formula (4), and a magnesium alkoxide represented by the following formula .

(3)

Ti (OR ¹⁾ ₄

[Chemical Formula 4]

Al (OR ²⁾ ₃

[Chemical Formula 5]

Mg (OR ³⁾ ₂

Wherein R ¹ , R ² and R ³ are the same or different and each is a hydrogen atom or a C ₁ to C ₂₀ alkyl group (Alkyl), a C ₂ to C ₂₀ alkenyl group (Alkenyl A C ₃ to C ₂₀ cycloalkyl group, a C ₆ to C ₂₀ aryl group, a C ₁ to C ₂₀ alkylsilyl group, a C ₇ to C ₂₀ arylalkyl group, or C ₇ - alkyl means an aryl group (alkylaryl) of C _20.

According to an embodiment of the present invention, each of R ¹ , R ² and R ³ may be the same or different from each other and may be a hydrogen atom or a C ₁ -C ₄ alkyl group.

According to one embodiment of the present invention, the composite metal oxide can be obtained by the following reaction formulas 1 to 3.

First, Titanium alkoxide represented by Chemical Formula 3 and Aluminum alkoxide represented by Chemical Formula 4 are mixed with water and an ethanol solvent as shown in Reaction Scheme 1, whereby titanium and aluminum metal are oxidatively bonded The composite oxide can be made in the form of a single molecule or an oligomer.

[Reaction Scheme 1]

Next, titanium (Ti) -aluminum (Al) -magnesium (Mg) -oxy is alternately coupled by introducing a magnesium alkoxide represented by Chemical Formula 5 into the reaction product of Reaction Scheme 1 according to the following Reaction Scheme 2 A metal alkoxide structure forming a stable hexagonal structure can be formed.

[Reaction Scheme 2]

Alkyl and oxygen are alternately linked with each other as shown in the following Reaction Scheme 3 by replacing functional groups and alcohol groups bonded to titanium and aluminum by hydrolysis by adding water to the reactant of Reaction Scheme 2, A single molecule or an oligomer of the composite metal oxide forming the hexagonal ring of the composite metal oxide may be produced.

[Reaction Scheme 3]

The reactants according to Reaction Schemes 1 to 3 can be referred to as coprecipitate because they are obtained by precipitating titanium alkoxide, aluminum alkoxide, and magnesium alkoxide in the form of complex oxide upon addition of water and ethanol solvent.

According to one embodiment of the present invention, the amount of the titanium alkoxide, aluminum alkoxide, and magnesium alkoxide to be used is not particularly limited and may be, for example, about 10: 1: 1 to about 1: 1: 1.

As described above, the titanium alkoxide, the aluminum alkoxide, and the magnesium alkoxide are dissolved in the presence of ethanol according to Reaction Schemes 1 to 3, and water mixed with ethanol at room temperature is added thereto. Can be easily obtained.

As described above, the composite metal oxide catalyst contained in the catalyst composition of the present invention can be produced by a relatively simple method, and is stable in moisture and easy to store. Unlike the antimony-based catalyst, the metal complex oxide has a relatively low metal self-toxicity and is unlikely to cause human and environmental problems.

The catalyst composition of the present invention comprises an aluminum-based compound.

The aluminum-based compound refers to a compound containing aluminum (Al), and examples thereof include an aluminum chelate compound, an aluminum alkoxide, a carboxylate of aluminum, or an inorganic acid salt of aluminum, but the present invention is not limited thereto .

More specifically, the aluminum-based compound may be selected from, for example, ethylene glycol aluminum, aluminum acetate, aminoethanol aluminum, aluminum acetylacetonate, aluminum acetylacetate, acetylacetate), aluminum ethyl acetoacetate (aluminum acetoacetate), aluminum chelate (aluminum chelate) compounds, aluminum methoxide (aluminum methoxide), aluminum ethoxide (aluminum ethoxide), aluminum in n-propoxide (n -propoxide aluminum), aluminum iso - propoxide (aluminum iso -propoxide), aluminum n - butoxide (aluminum n -butoxide), aluminum t - butoxide (aluminum t -butoxide), such as aluminum alkoxide (aluminum alkoxide), trimethyl aluminum (trimethyl aluminum ), Triethyl aluminum and the like, An organic aluminum compound, a formic acid aluminum, an acetic acid aluminum, a propionic acid aluminum, an oxalic acid aluminum, an acrylic acid aluminum, an aluminum laurate A carboxylic acid salt such as Lauric acid aluminum, Stearic acid aluminum, Citric acid aluminum, Lactic acid aluminum and Salicylic acid aluminum, Inorganic acid salts such as aluminum chloride, aluminum hydroxide, aluminum carbonate, aluminum phosphate, and phosphonic acid aluminum, aluminum metal, But the present invention is not limited thereto.

According to the present invention, the catalytic activity of the composite metal oxide can be further improved by including the aluminum-based compound.

In the catalyst composition of the present invention, the mixing ratio of the composite metal oxide and the aluminum-based compound is not particularly limited. However, in order to ensure sufficient catalytic activity, the content of the Ti element contained in the composite metal oxide and the Al element contained in the aluminum- The molar ratio of Ti: Al is 1: 5 to 1: 100, preferably 1:10 to 1:50.

According to an embodiment of the present invention, the catalyst composition of the present invention may further comprise a phosphorus compound in addition to the composite metal oxide and the aluminum-based compound.

The phosphorus compound refers to a compound containing phosphorus (P), and includes, for example, trimethyl phosphate, triethyl phosphate, triphenyl phosphate, phosphoric acid, , Phenylphosphine, 2-carboxyethylphenyl phosphinic acid, or a mixture thereof, but the present invention is not limited thereto.

The phosphorus compound serves to prevent the yellowing of the polyester which is formed by reducing pyrolysis during the polymerization reaction of the polyester and inhibiting the formation of a colorbody.

Unlike the antimony catalyst, the catalyst composition of the present invention has a relatively low metal toxicity and shows a low possibility of causing human and environmental problems, and exhibits high activity within a short reaction time even in a small amount. Also, the polyester produced using the catalyst composition of the present invention is excellent in physical properties such as viscosity and color. Therefore, it can be applied to commercial use in the mass production of polyester, in particular, in the production of polyethylene terephthalate.

Method for producing polyester

The method for producing polyester of the present invention is a method for producing a polyester by polymerizing a dicarboxylic acid component and a glycol component in the presence of a catalyst composition comprising a composite metal oxide containing titanium (Ti), aluminum (Al), and magnesium (Mg) .

The step of polymerizing the polyester may be carried out by liquid phase polymerization or solid phase polymerization.

According to an embodiment of the present invention, the step of polymerizing the dicarboxylic acid component and the glycol component includes a step of esterifying the dicarboxylic acid component and the glycol component, and polycondensation of the reaction product of the esterification reaction .

More specifically, first, the dicarboxylic acid component and the glycol component are esterified.

According to one embodiment of the present invention, the dicarboxylic acid component includes, for example, terephthalic acid, oxalic acid, malonic acid, azelaic acid, It is also possible to use an organic acid such as fumaric acid, pimelic acid, suberic acid, isophthalic acid, dodecane dicarboxylic acid, naphthalene dicarboxylic acid acid, biphenyldicarboxylic acid, 1,4-cyclohexane dicarboxylic acid, 1,3-cyclohexane dicarboxylic acid, 1,3-cyclohexane dicarboxylic acid, dicarboxylic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, 2,6-naphthalene dicarboxylic acid, acid, 1,2-Norbornane dicarboxylic acid, 1,3-cyclohexane dicarboxylic acid (Dicar but are not limited to, cyclohexane dicarboxylic acid, cyclohexane dicarboxylic acid, 1,3-cyclobutane dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid, Dicarboxylic acid, 5-sodium sulfoisophthalic acid, 5-potassium sulfoisophthalic acid, 5-lithium sulfoisophthalic acid, or 2- Sodium sulfoterephthalic acid, and the like. However, the present invention is not limited thereto. Other dicarboxylic acids not exemplified in the above may be used as long as they do not impair the object of the present invention. Preferably, terephthalic acid may be used as the dicarboxylic acid component.

According to one embodiment of the present invention, the glycol component includes, for example, ethylene glycol, 1,2-propylene glycol, 1,2-butylene glycol, Butylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 1,5-pentanediol, neopentyl glycol, Propylene glycol, diethylene glycol, triethylene glycol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,3-cyclohexanediol, Cyclohexanediol, propanediol, 1,6-hexanediol, neopentyl glycol, tetramethylcyclobutanediol, 1,4-cyclohexanediol, 1,4-cyclohexanediol, But are not limited to, cyclohexane diethanol, 1,10-decamethylene glycol, 1,12-dodecanediol (Dod alicyclic glycols such as eicosanediol, eicosanediol, eganediol, polyoxyethylene glycol, polyoxymethylene glycol and polyoxytetramethylene glycol; hydroquinone, 4,4'-di Dihydroxybisphenol, 1,4-bis (? -Hydroxyethoxy) benzene, 1,4-bis (? -Hydroxyethoxyphenyl) sulfone (Bis bis (p-hydroxyphenyl) ethane, bisphenol A, bisphenol S, 2,5-naphthalenediol, and the like, Examples of the aromatic glycol include, but are not limited to, and other glycols can be used as long as they do not impair the object of the present invention. Preferably, ethylene glycol may be used as the glycol component.

According to one embodiment of the present invention, the step of esterifying the dicarboxylic acid component and the glycol component is carried out at a temperature of about 200 to about 300 캜, preferably about 230 to about 280 캜, at a temperature of about 1 to about 6 Hour, preferably about 2 to about 5 hours.

Next, the reaction product of the esterification reaction is polycondensed.

The polycondensation of the reactants of the esterification reaction is carried out at a temperature of from about 200 to about 300 DEG C, preferably from about 260 DEG C to about 290 DEG C, and from about 0.1 to about 1 torr for from about 1 to about 5 hours, Is maintained for a period of from about 1 hour to about 3 hours, more preferably from about 1 hour to about 2 hours And the like. Therefore, since the polycondensation time can be remarkably shortened compared with the case of using the conventional catalyst, the productivity is improved.

In the method for producing polyester of the present invention, the catalyst composition comprising a composite metal oxide containing titanium (Ti), aluminum (Al), and magnesium (Mg) and an aluminum compound is as described above.

In the process for producing the polyester of the present invention, the catalyst composition can be introduced at any stage of the polyester polymerization. For example, according to one embodiment of the present invention, the catalyst composition may be introduced into the polycondensation step of the esterification reaction.

According to an embodiment of the present invention, the catalyst composition may be added in the polycondensation step, and optionally the composite metal oxide may be separately added to the esterification reaction step.

In the method for producing a polyester of the present invention, in the case of the composite metal compound, the content of the titanium (Ti) element contained in the composite metal compound is about 10 ppm or less, for example, About 1 to about 10 ppm, preferably about 2 to about 8 ppm, can be used.

The titanium-based catalyst compound used in the conventional polyester production method usually uses at least 10 ppm or more based on the content of the titanium element based on the final polyester, and when the polycondensation is attempted using less than 10 ppm, There is a problem that a reaction time is lengthened and a polyester having a low viscosity is produced. However, when the content of titanium is increased, the color of the polyester product is shifted to the yellow side, which may be inadequate for commercial use, and the catalytic activity is excessively high, so that it is difficult to stably control various physical properties including the byproduct content in the polymerization process.

In the method for producing polyester of the present invention, the composite metal oxide contained in the catalyst composition may exhibit a high catalytic activity even at a low content, while reducing deterioration of physical properties such as yellowing.

The aluminum-based compound is mixed with the composite metal oxide to increase catalytic activity. More specifically, according to the present invention, a polycondensation reaction can be carried out even when a small amount of the composite metal oxide catalyst is used by using an aluminum-based compound together with a composite metal oxide catalyst. It is also possible to obtain a product having a high viscosity with a short reaction time. Therefore, since the amount of titanium used can be reduced, the production cost can be reduced, which is economically and industrially advantageous. In addition, there is an additional advantage that it is soluble in the glycol component at room temperature and is simple to use and does not react with the composite metal oxide catalyst, phosphorus compound, and other additives, so that it can be mixed with other materials and introduced.

In the method for producing a polyester of the present invention, in the case of the aluminum compound contained in the catalyst composition, the amount of the aluminum (Al) element contained in the aluminum compound is preferably from about 10% About 200 ppm, preferably about 20 to about 100 ppm, may be used. Addition of an aluminum compound in the above range is preferable in view of production of polyester of excellent product by decreasing the viscosity increase and polycondensation time in the polyester polymerization.

Further, according to an embodiment of the present invention, a coloring agent may be further added to improve color. Examples of the coloring agent include cobalt acetate, cobalt acetylacetonate, cobalt benzoylacetonate, cobalt hydroxide, cobalt bromide, cobalt chloride, cobalt acetate, Cobalt iodide, Cobalt fluoride, Cobalt cyanide, Cobalt nitrate, Cobalt sulfate, Cobalt selenide, and the like. But are not limited to, compounds including cobalt such as cobalt phosphate, cobalt oxide, cobalt thiocyanate, or cobalt propionate.

The addition amount of the coloring agent can be added in an amount of about 150 ppm or less, for example, about 30 to about 150 ppm, and preferably about 60 to about 100 ppm, based on the final polyester. It is known that the cobalt compound itself has a certain degree of catalytic activity. However, if it is added to an extent that exhibits a catalytic effect, the residual metal in the polyester increases, leading to toxicity and a decrease in brightness. Therefore, when added in the above range, coloring can be inhibited without causing deterioration of the brightness or thermal stability of the polyester.

In addition, the step of adding the cobalt compound in the present invention is not limited to the step of esterifying the dicarboxylic acid component and the glycol component during the polymerization reaction or polycondensation of the reactant of the esterification reaction, and it can be administered at any stage . In addition, other cobalt-based compounds can be used as long as they do not impair the object of the present invention.

Examples of the polyester obtained by the production method of the present invention include polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, poly (1,4-cyclohexanedimethylene (Ethylene terephthalate), poly (ethylene terephthalate), polyethylene naphthalate, polybutylene naphthalate, polypropylene naphthalate, and copolymers thereof.

According to the process for producing a polyester of the present invention, the polyester may be formed by liquid phase polymerization, and the polyester formed may have an intrinsic viscosity ranging from about 0.58 to about 0.67 dl / g.

According to the process for producing a polyester of the present invention, the polyester can be formed by solid-state polymerization, and the formed polyester has an intrinsic viscosity of about 0.82 to about 0.90 dl / g.

The polyester produced by the process for producing a polyester of the present invention may preferably be polyethylene terephthalate. In addition, although its use is not particularly limited, it can be widely used in drinking water bottles, food packaging materials, films, or fibrous plastics which require particularly excellent color, transparency and brightness.

Hereinafter, the present invention will be described in more detail with reference to examples according to the present invention. It is to be understood, however, that these embodiments are merely illustrative of the invention and are not intended to limit the scope of the invention.

< Example >

Experimental conditions

        In the examples, the synthesis of the composite metal oxide (Ti / Al / Mg) proceeded in the atmosphere in contact with air or moisture.

The synthesis of ethylene glycol aluminum (Al (C ₂ H ₄ O ₂ ) ₂ ) was carried out under the condition that the solvent and nitrogen (N ₂ ) were completely removed from the water.

In the case of composite metal oxides, ethanol or methanol was used without any particular purification for the reaction solvent for synthesis. For the synthesis of ethylene glycol aluminum compound, Tetrahydrofuran solvent and ethylene glycol were used. Other examples include titanium isopropoxide, aluminum chloride, aluminum isopropoxide, magnesium methoxide, cobalt acetate, triethyl phosphate, terephthalate, Terephthalic acid was used without any special purification process.

Manufacturing example  One

Composite metal oxide ( Ti / Al / Mg )

Titanium isopropoxide and aluminum isopropoxide were dissolved in ethanol by heating. Magnesium methoxide (6-7 wt% in methanol) was slowly added thereto using a syringe. Next, distilled water and ethanol were mixed, and the diluted solution was slowly added dropwise at room temperature (23 ° C) over 30 minutes.

The mixture was stirred for 1 hour, and the resulting white precipitate was filtered using a glass filter. The collected solid was extracted in air, the residue was washed with distilled water (10 mL x 2), and then ethanol (20 mL x 2).

The product was dried at 70-80 DEG C for 8 hours under vacuum to obtain a composite metal oxide comprising Ti, Al, and Mg.

Manufacturing example  2

Ethylene glycol aluminum ( Al ( C ₂ H ₄ O ₂ ) ₂ )

A certain amount of aluminum chloride (AlCl ₃ ) is dissolved in THF at room temperature. Ethylene glycol was slowly added thereto using a syringe. After stirring the mixture for 1 hour, the resulting white precipitate was filtered off with air and exposure, filtered using a glass filter and the collected solid was washed with hexane (20 mL x 2).

The resulting white solid compound was vacuum-dried at room temperature for 7 hours to obtain an ethylene glycol aluminum catalyst.

Example  1a

Polyethylene Terephthalic  Liquid phase polymerization

Terephthalic acid (7.25 Kg, 43.7 mol), monoethylene glycol (3.21 Kg, 52.4 mol) and isophthalic acid (0.224 Kg, 3 mol) were placed in a reactor and heated with stirring at 240 ° C And the temperature is raised. When the tower temperature sensor connected to the reactor and generated in the reaction process and measuring distilled water is lowered from 240 ° C to 130 ° C, the reaction is stopped and the oligomer BHET (Bis -hydroxyethylene terephthalate.

Is dissolved by applying heat for 1 hour, the created oligomer at 260 ℃, comprising a glycol aluminum _{(Al (C 2 H 4 O} 2) 2) obtained in Production Example 1, a composite metal oxide and the preparation obtained in Example 2 The catalytic composition, triethylphosphate and cobalt acetate were dissolved in ethylene glycol and then put together. The pressure of the polycondensation reactor was reduced from 28 torr to 0.5 torr over 60 minutes, and the temperature was raised from 260 ° C to 280 ° C gave. When the intensity of the stirrer torque reached a certain level, the reaction was stopped when the polycondensation reaction was completed.

After completion of the reaction, the reaction product was solidified using cooling water to obtain a polyethylene terephthalate (PET) resin having an intrinsic viscosity of 0.63 dl / g.

Example  1b

Polyethylene Terephthalic Solid state polymerization

The polyethylene terephthalate resin obtained in the liquid phase polymerization of Example 1a was dried in air to remove water. The resin was placed in a solid state polymerization apparatus and the reaction temperature was maintained at 100 ° C for 1 hour, 130 ° C for 2 hours, 170 ° C for 2 hours, 225 ° C for 8 hours, Were subjected to solid phase polymerization for 13 hours and 50 minutes.

After completion of the reaction, a polyethylene terephthalate resin having a crystalline solid structure in the form of a white solid compound and having an intrinsic viscosity of 0.83 dl / g was obtained.

Example  2

Except that aluminum acetate (AlOH (OAc) ₂ , Sigma-Aldrich) was used as the aluminum-based compound Liquid phase polymerization was carried out in the same manner as in Example 1a to obtain a polyethylene terephthalate resin.

Example  3

Except that aluminum isopropoxide (Al (O i -Pr) ₃ , Sigma-Aldrich) was used as the aluminum-based compound Liquid phase polymerization was carried out in the same manner as in Example 1a to obtain a polyethylene terephthalate resin.

Comparative Example  1 to 15

Liquid phase polymerization was carried out in the same manner as in Example 1a, except that the kind of the catalyst and the amount of the catalyst were used, to obtain a polyethylene terephthalate resin.

Comparative Example  16

The polyethylene terephthalate resin obtained in the liquid phase polymerization of Comparative Example 15 was subjected to solid phase polymerization in the same manner as in Example 1b above to obtain a polyethylene terephthalate resin.

The catalysts and their contents used in Examples 1a to 3 and Comparative Examples 1 to 16 are shown in Table 1 below.

division Type of polymerization Catalyst composition PET reference element
Content (unit: ppm) Example 1a Liquid phase polymerization A composite metal oxide (Ti / Al / Mg) + an aluminum compound (Al (C ₂ H ₄ O ₂ ) ₂ ) Al (C ₂ H ₄ O ₂ ) ₂ : Al = 40,
Composite metal oxide: Ti = 3, Al = 0.25, Mg = 0.22 Example 1b Solid state polymerization A composite metal oxide (Ti / Al / Mg) + an aluminum compound (Al (C ₂ H ₄ O ₂ ) ₂ ) Al (C ₂ H ₄ O ₂ ) ₂ : Al = 40,
Composite metal oxide: Ti = 3, Al = 0.25, Mg = 0.22 Example 2 Liquid phase polymerization A composite metal oxide (Ti / Al / Mg) + an aluminum compound (AlOH (OAc) ₂ ) AlOH (OAc) ₂ : Al = 40,
Composite metal oxide: Ti = 3, Al = 0.25, Mg = 0.22 Example 3 Liquid phase polymerization (Ti / Al / Mg) + aluminum compound (Al (O i -Pr) ₃ ) Al (O i -Pr) ₃ : Al = 40,
Composite metal oxide: Ti = 3, Al = 0.25, Mg = 0.22 Comparative Example 1 Liquid phase polymerization Ti catalyst (Ti (C ₂ H ₄ O ₂ ) ₂ ) + The aluminum-based compound (Al (C ₂ H ₄ O ₂ ) ₂ ) Al = 40, Ti = 3 Comparative Example 2 Liquid phase polymerization Ti catalyst (Ti (OEt) ₄ ) + The aluminum-based compound (Al (C ₂ H ₄ O ₂ ) ₂ ) Al = 40, Ti = 3 Comparative Example 3 Liquid phase polymerization Ti catalyst (Ti (C ₂ H ₄ O ₂ ) ₂ ) + aluminum compound (AlOH (OAc) ₂ ) Al = 40, Ti = 3 Comparative Example 4 Liquid phase polymerization Ti catalyst (Ti (OEt) ₄ ) + The aluminum compound (AlOH (OAc) ₂ ) Al = 40, Ti = 3 Comparative Example 5 Liquid phase polymerization Ti catalyst (Ti (C ₂ H ₄ O ₂ ) ₂ ) + aluminum compound (Al (O i -Pr) ₃ ) Al = 40, Ti = 3 Comparative Example 6 Liquid phase polymerization Ti catalyst (Ti (OEt) ₄ ) + aluminum compound (Al (O i -Pr) ₃ ) Al = 40, Ti = 3 Comparative Example 7 Liquid phase polymerization Ti catalyst (Ti (C ₂ H ₄ O ₂ ) ₂ ) + Aluminum-based compounds (AlCl ₃₎ Al = 40, Ti = 3 Comparative Example 8 Liquid phase polymerization Ti catalyst (Ti (OEt) ₄ + Al compound (AlCl ₃₎ Al = 40, Ti = 3 Comparative Example 9 Liquid phase polymerization The composite metal oxide (Ti / Al / Mg) Ti = 3, Al = 0.25, Mg = 0.22 Comparative Example 10 Liquid phase polymerization Ti catalyst (Ti (C ₂ H ₄ O ₂ ) ₂ ) Ti = 3 Comparative Example 11 Liquid phase polymerization Ti catalyst (Ti (OEt) ₄ ) Ti = 3 Comparative Example 12 Liquid phase polymerization The aluminum-based compound (Al (C ₂ H ₄ O ₂ ) ₂ ) Al = 40 Comparative Example 13 Liquid phase polymerization The aluminum compound (AlOH (OAc) ₂ ) Al = 40 Comparative Example 14 Liquid phase polymerization The aluminum-based compound (Al (O i -Pr) ₃ ) Al = 40 Comparative Example 15 Liquid phase polymerization Sb catalyst (Sb (OAc) ₃ ) Sb = 250 Comparative Example 16 Solid state polymerization Sb catalyst (Sb (OAc) ₃ ) Sb = 250

How to measure physical properties of polymers

Intrinsic viscosity ( Intrinsic Viscosity , IV )

Phenol and 1,1,2,2-tetrachloroethanol were mixed in a weight ratio of 6: 4, and 0.4 g of the polyester resin to be measured was added to 100 mL of the reagent. After dissolution for 90 minutes, Ubbelohde Transfer it to a viscometer and keep it in a 30 ° C thermostat for 10 minutes. Use a viscometer and an aspirator to determine the number of drops of solution. The number of drops of the solvent was also found by the same method, and then R.V. Value and I.V. Values were calculated. In the following equation, C represents the concentration of the sample.

[Equation 1]

R.V. = Samples falling in water / solvent drops in seconds

[Equation 2]

IV = 1/4 (RV-1) / C + 3/4 (in RV / C)

The carboxyl terminal end ( Carboxylic end group , CEG , - COOH ) Concentration

0.5 g of a polyester resin of 4 mm in size to be measured was placed in a 100 mL dissolution tube, and 25 mL of an ortho-chlorophenol solvent was added and dissolved at 100 DEG C for 1 hour to prepare a sample. The sample was titrated with 0.02 M KOH methanol solution and measured. The number of carboxyl groups is referred to as carboxylic group equivalent / polymer of 10 ⁶ g (or mmol / kg).

Hydroxyl end ( Diethylene glycol , DEG , - OH ) Concentration

0.5 g of the polyester resin to be measured in a size of 4 mm was placed in a 100 mL dissolution tube and 25 mL of ortho-chlorophenol solvent was added and dissolved at 100 DEG C for 1 hour to prepare a sample. 50 mL of an excess amount of adipic acid was added to the sample, and the reaction was carried out at 100 DEG C for 1 hour to replace the terminal hydroxyl group with the terminal carboxyl group. After removing the extra adipic acid, the difference between the terminal carboxyl group amount of the substituted sample and the terminal carboxyl group amount of the non-substituted sample was calculated.

Polyethylene Terephthalate  Resin color ( Color = L, a, b)

50 g of the polyester resin to be measured is an average value obtained by removing moisture from the air and putting it in a colorimeter model SA-2000 and measuring the color 10 times.

The L, a, and b color systems are used internationally as a basis for polyester color evaluation. These color values are one of the color systems for standardizing color measurements and describe recognizable colors and color differences. In this system, L is the brightness factor and a and b are the color measurement numbers. In general, the b value indicating the yellow / blue balance is an important figure in the manufacture of drinking water containers and food packaging materials. Positive b value means yellow discoloration and negative value means blue discoloration. Positive a value means red discoloration and negative value means green discoloration. The L value is a numerical factor indicating the brightness and is a very important value such as b value in the production of drinking water containers and food packaging materials.

Experimental Example  One

The time required for the polycondensation in Examples 1a to 3 and Comparative Examples 1 to 16 and the intrinsic viscosity of the polyethylene terephthalate resin obtained in each of the Examples and Comparative Examples are shown in Table 2 below.

   division Polycondensation time Intrinsic viscosity
(Unit: dl / g) Example 1a 1 hour 25 minutes 0.63 Example 1b        - 0.84 Example 2 1 hour 50 minutes 0.60 Example 3 1 hour 45 minutes 0.61 Comparative Example 1 2 hours 31 minutes 0.42 Comparative Example 2 2 hours 35 minutes 0.40 Comparative Example 3 2 hours 50 minutes 0.39 Comparative Example 4 2 hours 47 minutes 0.41 Comparative Example 5 2 hours 32 minutes 0.44 Comparative Example 6 2 hours 34 minutes 0.43 Comparative Example 7 3 hours 10 minutes 0.37 Comparative Example 8 3 hours 15 minutes 0.35 Comparative Example 9 3 hours 05 minutes 0.35 Comparative Example 10 3 hours and 30 minutes 0.31 Comparative Example 11 3 hours and 30 minutes 0.30 Comparative Example 12 3 hours 40 minutes 0.28 Comparative Example 13 3 hours 50 minutes 0.28 Comparative Example 14 3 hours and 30 minutes 0.30 Comparative Example 15 2 hours 23 minutes 0.59 Comparative Example 16 - 0.81

Referring to Table 2, in the case of producing polyethylene terephthalate using the catalyst composition of the present invention, the time required for the polycondensation reaction was from 1 hour to 25 minutes to 1 hour and 49 minutes, which was much shorter than when using the conventional aluminum catalyst or titanium alone. Although organic dyes are generally used in the case of using titanium catalysts, the present invention does not use organic dyes using a minimum amount of titanium catalyst. Therefore, the polyethylene terephthalate produced at this time was able to obtain polyethylene terephthalate having good physical properties such as transparency and color. Also, the polycondensation time of the catalyst was shortened compared to the antimony catalyst, and the intrinsic viscosity was also satisfactory in both the liquid phase polymerization and the solid phase polymerization.

In addition, the polyethylene terephthalate obtained by the liquid phase polymerization in Examples exhibited a viscosity of 0.60 to 0.63 dl / g.

However, in the case of Comparative Examples 1 to 14, even though the polycondensation time was 2 hours and 30 minutes or more, only the result of an intrinsic viscosity of about 0.5 dl / g or less was obtained. As a result, the polymer could not be normally formed.

Experimental Example  2

Color (L, a, b) values, CEG concentration, and DEG concentrations of the polyethylene terephthalate resin obtained in Examples 1a and 1b and Comparative Examples 15 and 16 were measured and shown in Table 3 below.

division Color CEG concentration
(Unit: mmol / Kg) DEG concentration
(Unit: wt%) L a b Example 1a 54.2 0.3 -1.5 15.4 2.94 Example 1b 79.8 -0.5 -2.0 16.2 2.42   Comparative Example 15   53.7    0.5   -1.0 20.7 4.10   Comparative Example 16   78.6   -0.2   -1.3 21.8 3.81

With reference to Table 3 above, the polyethylene terephthalate obtained by the solid-state polymerization of the present invention had an equivalent or higher Color value, CEG concentration, and DEG concentration were obtained. In the case of the liquid phase polymerization and the solid phase polymerization of Comparative Examples 15 and 16, the polycondensation using the antimony catalyst showed a longer polycation time and lower intrinsic viscosity than the catalyst composition of Example 1a. In addition, in Examples 1a and 1b, the physical properties (color color, CEG concentration, DEG concentration) of polyethylene terephthalate produced from Comparative Examples 15 and 16 using an antimony catalyst were excellent.

Industrial availability

According to the present invention, a mixture of an aluminum catalyst and a composite metal oxide catalyst is an environmentally friendly catalyst composition capable of replacing antimony, and a polyester produced using the catalyst is provided. The polyester of the present invention can be applied to drinking water bottles, fruit juice bottles, various kinds of molded articles such as medical fibers, industrial material fibers, various films and sheets, and particularly beverage / food storage containers sensitive to human body.

Claims (19)

A composite metal oxide including titanium (Ti), aluminum (Al), and magnesium (Mg); And
A catalyst composition for polyester polymerization comprising an aluminum-based compound.
The catalyst composition for polyester polymerization according to claim 1, wherein the composite metal oxide is represented by the following formula (1) or (2)
[Chemical Formula 1]

(2)

In Formula 2, n is an integer of 2 to 20.
The catalyst according to claim 1, wherein the composite metal oxide is a catalyst for polyester polymerization, which is a coprecipitate of a titanium alkoxide represented by the following formula (3), an aluminum alkoxide represented by the following formula (4), and a magnesium alkoxide represented by the following formula Composition:
(3)
Ti (OR ¹⁾ ₄
[Chemical Formula 4]
Al (OR ²⁾ ₃
[Chemical Formula 5]
Mg (OR ³⁾ ₂
In the above formulas (3), (4) and (5)
R ¹ , R ² and R ³ are each independently a hydrogen atom or a C ₁ to C ₂₀ alkyl group (Alkyl), a C ₂ to C ₂₀ alkenyl group, a C ₃ to C ₂₀ cycloalkyl group _{(Cycloalkyl), C 6 ~ C} 20 aryl group (aryl), C group ₁ ~ C ₂₀ alkyl silyl (alkylsilyl), an alkyl aryl of C ₇ ~ C ₂₀ aryl group (arylalkyl) or C ₇ ~ C ₂₀ of the group (Alkylaryl).
The catalyst composition for polyester polymerization according to claim 1, wherein the aluminum compound comprises at least one member selected from the group consisting of an aluminum chelate compound, an aluminum alkoxide, a carboxylate of aluminum, and an inorganic acid salt of aluminum.
The method of claim 1 wherein the aluminum containing compound is glycol, aluminum aminoethanol aluminum, aluminum acetate, aluminum acetylacetate, aluminum methoxide, aluminum ethoxide, aluminum n - propoxide, aluminum iso - propoxide, aluminum n -Butoxide, trimethylaluminum, and triethylaluminum. &Lt; Desc / Clms Page number 18 &gt;
The composite metal oxide and the aluminum-based compound according to claim 1, wherein the composite metal oxide and the aluminum-based compound have a molar ratio of Ti: Al of 1: 5 to 5: 1 based on the content of the Ti element contained in the composite metal oxide and the Al element contained in the aluminum- 1: &lt; RTI ID = 0.0 &gt; 100. &Lt; / RTI &gt;
A method for producing a polyester comprising a step of polymerizing a dicarboxylic acid component and a glycol component in the presence of a catalyst composition comprising a composite metal oxide comprising titanium (Ti), aluminum (Al), and magnesium (Mg) &Lt; / RTI &gt;
The method for producing a polyester according to claim 7, wherein the composite metal oxide is contained so that the content of the titanium (Ti) element contained in the composite metal oxide is 1 to 10 ppm based on the weight of the polyester.
8. The method according to claim 7, wherein the aluminum compound is contained in an amount of 10 to 200 ppm based on the aluminum (Al) element content of the aluminum compound based on the weight of the polyester &Lt; / RTI &gt;
8. The method of claim 7, wherein the step of polymerizing the dicarboxylic acid component and the glycol component comprises the step of esterifying the dicarboxylic acid component and the glycol component, and polycondensation of the reactants of the esterification reaction A method for producing a polyester.
11. The method of producing a polyester according to claim 10, wherein the catalyst composition is added to the polycondensation reaction product of the esterification reaction.
8. The method for producing a polyester according to claim 7, wherein the composite metal oxide is represented by the following formula 1 or 2:
[Chemical Formula 1]

(2)

In Formula 2, n is an integer of 2 to 20.
8. The method for producing a polyester according to claim 7, wherein the aluminum compound comprises at least one member selected from the group consisting of an aluminum chelate compound, an aluminum alkoxide, a carboxylate of aluminum, and an inorganic acid salt of aluminum.
The method of claim 7, wherein the aluminum-based compound is ethyleneglycol aluminum, aminoethanol aluminum, aluminum acetate, aluminum acetylacetate, aluminum methoxide, aluminum ethoxide, aluminum n - propoxide, aluminum iso - propoxide, aluminum n - butoxide, trimethylaluminum, and triethylaluminum.
The method for producing a polyester according to claim 7, which is carried out by liquid phase polymerization or solid phase polymerization.
16. The method of producing a polyester according to claim 15, wherein the polyester is formed by liquid phase polymerization and has an intrinsic viscosity of 0.58 to 0.67 dl / g.
16. The method of producing a polyester according to claim 15, wherein the polyester is formed by solid state polymerization and has an intrinsic viscosity of 0.82 to 0.90 dl / g.
The method of producing a polyester according to claim 7, wherein the polyester is used in a drinking water bottle, a fruit juice bottle, a food packaging material, a film or a fibrous plastic.
The method of producing a polyester according to claim 7, wherein the polyester is polyethylene terephthalate.