KR100469901B1 - Catalyst composition for the preparation of polyester - Google Patents

Abstract

The present invention relates to a catalyst composition for producing a polyester resin, which is widely used in combination, textile, non-woven fabric, film, etc., in particular, it is possible to produce a resin having excellent correction properties and colors when forming a film, It is an object of the present invention to provide a catalyst composition having properties capable of minimizing its content.

The present invention is a polycondensation catalyst used in the production of a polyester resin, at least one compound selected from the group consisting of orthoesters and condensation orthoesters of titanium, zirconium, aluminum and alcohol solvents having two or more hydroxy, A catalyst composition composed of a organophosphorus compound of a specific structural formula and a base containing lithium metal ions is disclosed.

Description

Catalyst composition for polyester production {Catalyst composition for the preparation of polyester}

The present invention relates to a catalyst composition for producing polyester, and more particularly, a catalyst for producing polyester having the advantage of being capable of producing a resin having excellent electrostatic application characteristics and colors when forming a film and minimizing the content of heavy metals such as intimon. It relates to a composition.

Polyester resins are widely used in combination, textiles, nonwoven fabrics, films, and the like because of their excellent thermal, electrical, chemical and moisture resistance, water resistance and transparency.

Generally, polyesters use diacids and diols to produce low molecular weight oligomers through esterification or ester exchange reactions, which are then used as antimony compounds, germanium (GERMANIUM) and titanium. It is prepared by carrying out a polycondensation reaction using a polymerization catalyst such as (TITANIUM), and especially antimony compounds have been widely used in the commercial production of polyethylene terephthalate (PET). This is because the antimony compound has a relatively high catalytic activity and almost no byproducts. But. Disadvantages are that the antimony compounds are highly toxic and tend to change the color of the polymer to gray during the PET polymerization or in processing processes such as extrusion, and also in the T-die discharge, which is the filter or extruder outlet. It causes contamination problems and affects the yield of the process. Environmentally, antimony, a heavy metal, may eventually be ashed in an incineration plant, or effluent problems may arise due to landfilling.

On the other hand, the titanium compound (particularly titanium tetraalcoside) catalyst is a very active catalyst, but it is difficult to control the yellowing of the color tone and obtain transparent PET by forming titanium oxide particles through the coupling between the hydrolyzed catalysts. Titanium particles, which are difficult and produced, have not been used in applications such as films that accumulate in filters and require transparency, such as filaments that require continuous emission of color or yarn.

However, in recent years, research has been conducted in an improved direction in terms of environment, productivity and product quality by controlling PET's high activity and hydrolyzability well and efficiently producing PET with a small amount of catalyst. On the other hand, in order to control the rate of hydrolysis and to prevent turbidity due to gelation of the catalyst, chelating substances such as glycol, acetic acid, acetylacetone, and alpha-hydroxy carboxylic acid are introduced. In addition, methods of obtaining a transparent sol which does not precipitate by adding an acid or a base as a hydrolysis catalyst have been reported. (Sol-Gel Optics Processing and Applications, Kluer Academic Publishers, p261, p428, 1994).

For example, US Pat. No. 5,981,690 discloses the use of phosphonic acid, phosphonic acid and titanium tetrahydrocarbyl oxide (TETRAHYDROCARBYLOXIDE) in a diol solvent such as ethylene glycol as a catalyst to control the activity of titanium alkoxides. It is reported that a polyester having excellent permeability can be obtained, and US Pat. No. 6,080,834 discloses complex forming materials such as titanium tetrahydrocarbyl oxide (TETRAHYDROCARBYLOXIDE) and hydroxycarboxylate, phosphorus compounds such as phosphonic acid and phosphonic acid. And a reaction complex in ethylene glycol containing p-TOLUENESULFONIC ACID as a catalyst is disclosed. In addition, WO 01 / 56694A1 discloses complexing agents such as titanium tetrahydrocarbyl oxide (TETRAHYDROCARBYLOXIDE) and hydroxycarboxylates, and reaction complexes in ethylene glycol containing inorganic bases or organic bases which help complex formation as catalysts. A method of use is disclosed.

However, the methods listed above only introduce a chelating group to titanium to control the activity of the titanium catalyst, and substantially the polyester composition for preparing the polyester into fibers, resins, and biaxially oriented films. There are many problems. That is to say, for the hydrolysis of titanium tetraalkoxides, bases with alkali metals, for example sodium hydroxide, potassium hydroxide, calcium hydroxide or also amines, for example quaternary amine hydroxides (N (R) ₄ ⁺ OH) ^- ), These metal ions or amine compounds are added together with the titanium catalyst during polyester production and act as a decomposition reaction accelerator to deteriorate the color of the polyester and maintain the color to cobalt the fiber or bottle. There is a disadvantage that a large amount of complementary colorant should be added.

In addition, in order to manufacture polyester film, Amorphous sheet formation is important. In order to prevent crystallization, electrostatic application is generally used, and for proper electrostatic application, alkali metal salt (ALKALI METAL SALT) or alkaline earth is used. Metal salts (ALKALI EARTH METAL SALT) are required. The most commonly used metal ions are lithium monovalent cations and magnesium divalent cations with small atomic weights and ionic radii. However, polyesters polymerized with alkali metals, alkaline earth metal salts, or titanium catalysts containing quaternary amine hydroxides, which are presented as bases in the prior patents, have relatively high degree of color reduction, and have a large atomic weight and ionic radius. It is not appropriate, and therefore, the addition of metal ions requires more metal ions than titanium catalysts prepared using lithium bases, so that the sulfur change of the resin becomes more severe and inefficient. have.

In order to compensate for this, when using a phosphorus compound having a large binding force with a metal ion such as phosphoric acid or phosphorous acid, it is not expected to improve the reactivity, which is an advantage of the titanium catalyst, and also to the reaction between the pinning enhancer and the phosphorus compound. By particle formation, it adversely affects the filtering process.

The present invention has been made to solve the above problems, in particular, excellent performance as a polycondensation catalyst, as well as the production of polyester resins with excellent electrostatic application characteristics and color during film molding, and also heavy metals such as antimony in the resin The purpose is to provide a catalyst composition that can minimize the content of.

The present invention, in order to achieve the above object, at least one compound selected from the group consisting of orthoesters and condensed orthoesters of titanium, zirconium, aluminum and condensed orthoesters, alcohol having at least two hydroxy A catalyst composition comprising a solvent, an organophosphorus compound represented by the following Chemical Formula 1, and a base containing an alkali metal ion is disclosed.

[Formula 1]

(R'0) P (O) (OR ₁ ) CHRCO ₂ R "

(Wherein R ₁ , R ′, R ″ are alkyl, aryl, alcohol or polyols and R is H or phenyl)

Phosphorus compound of Chemical Formula 1 used in the present invention is used to control the catalytic activity of titanium and the like as well as to improve the color of the resin, as such a phosphonoacetic acid derivative having a carboxyl substituent at the alpha carbon position Specific examples thereof include trimethyl phosphonoacetate, triethyl phosphonoacetate, ester compounds of carboethoxyphosphonophenylacetic acid, triethyl phosphonoacetate and diol and Phosphorus compounds such as some or all of the transesterification reactants are suitable. Such phosphorus compounds having a carboxyl group at the alpha carbon position can control yellowing and control the catalytic activity of a metal catalyst such as titanium, and the content thereof is preferably in the range of about 0.1 to 4 moles per mole of the metal catalyst. .

Alcohol solvents having two or more hydroxyl groups used in the present invention are generally glycol components used in the preparation of polyesters, for example, ethylene glycol, propylene glycol, butane diol, neopentyl glycol, cyclohexanedimethanol, polyol And the like, and the amount thereof is preferably in the range of about 0.5 to 20 moles with respect to 1 mole of the metal catalyst. In this case, less than 0.5 moles may cause side reactions during catalyst preparation or storage, resulting in the formation of precipitates.

In addition, it is preferable to use an alkali metal compound as the base used in the present invention, but it is more preferable to use a lithium monovalent base for electrostatic application during color or film production. The base may be added alone or mixed with 1-Hydroxycarboxylic acid, which stabilizes by forming a complex upon hydrolysis of titanium tetraoxide, the content of which is approximately one mole of the metal catalyst. The range of 0.1-4 mol is preferable.

Even when a metal component is added during the polymerization reaction for the purpose of electrostatic application, by adding 0.1 to 4.0 moles of phosphorus compound with respect to 1 mole of the injected metal, a polyester resin for film having excellent color can be obtained. A very good color was obtained when using such a phosphorus compound with one carboxylic acid ester.

Generally, the polymerization of polyester is made by using dimethylene terephthalate as a starting material to make a low molecular oligomer through a transesterification reaction with diol and condensation reaction in vacuum to make a polymer, terephthalic acid as a raw material A method of making a polymer by condensation reaction of the resulting oligomer in vacuum after the reaction is generally used. The catalyst composition according to the present invention can be used both as a reaction catalyst in the oligomer formation step or as a catalyst in the condensation reaction step. In addition, it can be used in combination with a catalyst such as calcium, manganese, zinc, magnesium-based compounds, known as polycondensation catalysts, antimony, germanium, and the like, which are widely known as transesterification catalysts, and can also be used with other phosphorus compounds and antioxidants. have. In particular, cobalt ions are very useful additives for controlling the yellow color and can be added according to the required use, for example, for bottles, for fibers, and the like. In addition, the amount of the catalyst composition of the present invention is preferably in the range of about 1 to 100 ppm on the basis of Ti, Zr or Al elements in the polyester. In the case of a polyester film, fine unevenness is required on the surface of the film for the stretching or winding process. The microparticles are made of a polyester containing particles through polyester production or compounding, and the inorganic particles are poly After mixing with the ester in an appropriate ratio, it is well dried in the dryer and then melted out through the T-Die at the end of the extruder and adhered to the cooling roll by using an electrostatic application method. It can be obtained by successive biaxial stretching and simultaneous biaxial stretching. In this case, the metal ions in the polymer serve to closely adhere the sheet to the cooling roll when static electricity is applied. The catalyst composition according to the present invention includes a metal catalyst having excellent electrostatic application ability and not impairing color, and thus is capable of electrostatic adhesion without adding a large amount of electrostatic applied metal ions, which is advantageous for maintaining the color of polyester. .

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, wherein the evaluation of the resin was performed by the following method. That is, the resin was cut into pellets of a certain size and the average weight of one was 25mg ± 5mg, and the pellets were measured using a colorimeter. The color tone is L-value indicating whiteness and b-value indicating yellowness. L value is lighter as the value is higher, and yellow color is as b value is higher. The inherent viscocity (IV) of the polymer was measured by a capillary method using an ortho chlorophenol (O-CHLOROPHENOL) solvent.

Example 1

<Catalyst composition preparation>

218 g of ethylene glycol (3.52 mol) was added to a 500 ml flask under nitrogen atmosphere and 50 g of tetraisopropyl titanate (0.176 mol) was added over 30 minutes while stirring, followed by 17.8 g of 11 wt% lithium hydroxide aqueous solution. (0.082 mol lithium hydroxide) and 23.6 g of triethyl phosphonoacetate (0.106 mol) were added to obtain a light yellow catalyst composition.

<Polyester resin production>

1.9 kg of terephthalate and 0.82 kg of ethylene glycol were added to an oligomer composed of 1.9 kg of terephthalate and 0.82 kg of ethylene glycol prepared in advance in a reaction tube under a nitrogen atmosphere. The solution was charged to 25 ppm, and water was allowed to flow out at 1.0 KG pressure and approximately 230 ° C. to undergo esterification. Subsequently, the temperature was raised to 280 ° C. over 45 minutes and the condensation reaction was carried out under the condition that the reaction tube pressure was lowered to 1 tor or less from atmospheric pressure to obtain a polyester resin having an intrinsic viscosity of 0.615.

Example 2

<Catalyst composition preparation>

In the catalyst composition used in Example 1, 32.7 g (0.106) of a phosphorus compound having a phosphorus content of 10% and a ethanol group of 10% phosphorus of triethylphosphono acetate instead of triethyl phosphonoacetate was substituted with ethylene glycol. A catalyst composition was prepared in the same manner as in Example 1 except that mole) was added thereto.

<Polyester resin production>

A polyester resin having an intrinsic viscosity of 0.615 was obtained in the same manner as in Example 1 except that the catalyst composition prepared in Example 2 was used instead of the catalyst composition used in Example 1.

Example 3

<Catalyst composition preparation>

A catalyst composition was prepared in the same manner as in Example 2, except that 91.97 g (0.176 mol) of 40 wt% lithium citrate aqueous solution was added to the 11 wt% lithium hydroxide aqueous solution in the catalyst composition used in Example 2.

<Polyester resin production>

A polyester resin having an intrinsic viscosity of 0.615 was obtained in the same manner as in Example 1 except that the catalyst composition prepared in Example 3 was used instead of the catalyst composition used in Example 1.

Example 4

After the esterification reaction under the same conditions as in Example 3, in the initial stage of condensation, a magnesium acetate solution dissolved in ethylene glycol was further added so that the magnesium content of the final polymer was 60 ppm, and then triethyl phosphate acetate was added after 5 minutes. A polyester resin having an intrinsic viscosity of 0.615 was obtained in the same manner as in Example 3 except that the phosphorus content of the final polymer was 35 ppm.

Example 5

After reacting with the ester under the same conditions as in Example 3, in the initial stage of condensation, the magnesium acetate and antimony mixed solution further dissolved in ethylene glycol was added so that the antimony content in the final polymer was 50 ppm and the magnesium content was 60 ppm. After 5 minutes, triethyl phosphonoacetate was added in the same manner as in Example 3 except that the phosphorus content was 35 ppm in the final polymer, thereby obtaining a polyester having an intrinsic viscosity of 0.615.

Comparative Example 1

<Catalyst composition preparation>

218 g of ethylene glycol (3.52 mol) was added to a 500 ml flask under nitrogen atmosphere and 50 g of tetraisopropyl titanate (0.176 mol) was added over 30 minutes while stirring, followed by 22 g of 32 wt% aqueous sodium hydroxide solution (0.176 mol). ) Was slowly added, followed by 22.18 g of dibutyl phosphate (0.106 mol) to obtain a pale yellow catalyst composition.

<Polyester resin production>

A polyester resin having an intrinsic viscosity of 0.615 was obtained in the same manner as in Example 1 except that the catalyst composition prepared in Comparative Example 1 was used instead of the catalyst composition used in Example 1.

Comparative Example 2

<Catalyst composition preparation>

218 g of ethylene glycol (3.52 mol) was added to a 500 ml flask under nitrogen atmosphere and 50 g of tetraisopropyl titanate (0.176 mol) was added over 30 minutes while stirring, followed by 91.97 g of 40% wt% lithium sheet. Aqueous aqueous solution (0.176 mol) was added, followed by 10.5 g of dibutyl phosphate (0.05 mol) to obtain a pale yellow catalyst composition.

<Polyester resin production>

A polyester resin having an intrinsic viscosity of 0.615 was obtained in the same manner as in Example 1 except that the catalyst composition prepared in Comparative Example 2 was used instead of the catalyst composition used in Example 1.

The physical properties of the polyester resin obtained by the above Examples and Comparative Examples were measured and shown in Table 1 below.

TABLE 1

As can be seen from the examples and comparative examples, when the polyester resin is prepared using the catalyst composition according to the present invention, it is excellent in performance as a polycondensation catalyst and also capable of producing a resin having excellent electrostatic application properties and colors when forming a film. In addition, it is possible to obtain advantages such as minimizing the content of heavy metals such as antimony in the resin.

Claims (4)

Per mole of at least one compound selected from the group consisting of orthoesters of titanium, zirconium, aluminum and condensation orthoesters; 0.5-20 mol of alcohol solvents in which two or more hydroxy are present; 0.1 to 4 moles of an organophosphorus compound represented by Formula 1 below; And 0.1 to 4 moles of base containing lithium metal ions. [Formula 1] (R'0) P (O) (OR ₁ ) CHRCO ₂ R " (Wherein R ₁ , R ′, R ″ are alkyl, aryl, alcohol or polyols, R is H or phenyl) delete The catalyst composition for producing polyester according to claim 1, wherein the organophosphorus compound is a phosphonoacetic acid derivative having a carboxyl substituent at an alpha carbon position. The catalyst composition of claim 1, wherein the alcohol solvent is a solvent selected from ethylene glycol, propylene glycol, butanediol, neopentyl glycol, and cyclohexane dimethanol.