KR20170090701A - Manufacturing process of amorphous polyethyleneterephthalate polymer - Google Patents

Abstract

The purpose of the present invention is to produce an isosorbide polyethylene terephthalate polymer which has high transparency and expresses excellent mechanical properties by additionally introducing isosorbide substituted by acetic anhydride when producing a polyethylene terephthalate polymer. Accordingly, the present invention provides a method of producing an isosorbide polyethylene terephthalate polymer having high transparency comprising the steps of: performing a reaction of isosorbide and acetic anhydride of the same equivalent to acetylate isosorbide; a step of mixing the acetylated isosorbide, ethylene glycol (EG) and terephthalic acid (TPA) to prepare slurry; a step of performing an esterification reaction of the slurry; and a polycondensation reaction step.

Description

TECHNICAL FIELD [0001] The present invention relates to a method for producing amorphous polyethylene terephthalate polymer having high transparency,

The present invention relates to a process for preparing a copolymerized polyethylene terephthalate polymer, and more particularly, to a process for producing a copolymerized polyethylene terephthalate polymer, which comprises adding ethylene glycol (EG, Ethyleneglycol) and terephthalic acid (TPA, terephthalic acid) isosorbide, which is substituted with an anhydride, is introduced to produce an isosorbide polyethylene terephthalate polymer having high transparency and excellent mechanical properties.

Generally, polyester resins, especially polyethylene terephthalate resins, are linear polymers synthesized from dicarboxylic acids or ester-forming derivatives thereof and diols or ester-forming derivatives thereof, which are low in cost and excellent in mechanical properties and chemical properties But also has excellent gas barrier properties and is widely used for the production of various containers, films and fibers. On the other hand, the polyester is produced by condensation polymerization method. In the equilibrium reaction according to external conditions, a commercially available viscosity is obtained through high temperature and high vacuum conditions, and a certain amount of oligomer remains in the final polymer.

In order to improve the moldability of the polyester resin and to eliminate the crystallinity, polyester resins copolymerized with two or more glycol or dicarboxylic acid components have been widely used commercially. In the case of a homopolyester composed of only terephthalic acid and ethylene glycol, it is possible to improve physical properties and heat resistance through stretching crystallization and heat fixation, but there are limitations in application and improvement in heat resistance, In the case of polyester, there is a drawback that it is difficult to improve the heat resistance by the stretching or crystallization process. As another method for improving the heat resistance of polyester, a method of using isosorbide, which is an environmentally-friendly diol compound derived from starch, as one of monomers is known, and is widely used for high heat resistant materials. It is widely used in beverage bottles, but it has not been used in industrial fibers that require high heat resistance.

Korean Patent No. 1,058,974 Korea Patent Publication No. 2011-0028696

It is an object of the present invention to provide a method for producing an isosoboid polyethylene terephthalate polymer which is excellent in transparency and exhibits excellent mechanical properties by further introducing an isosorbide substituted with anhydride to acetic acid in the production of a polyethylene terephthalate polymer.

According to one aspect of the present invention, there is provided a process for preparing a compound of formula (I), comprising the steps of reacting isosorbide and acetic anhydride in the same amount to acetylate isosorbide; Mixing the acetylated isosorbide, ethylene glycol (EG), and terephthalic acid (TPA) to prepare a slurry; An esterification reaction step of the slurry; And a polycondensation reaction step; The present invention also provides a method for producing an isosorbide polyethylene terephthalate polymer having high transparency.

At this time, the reaction temperature of isosorbide and acetic anhydride is 130 to 140 ° C, the esterification reaction temperature is 250 to 270 ° C, and the polycondensation reaction temperature is 270 to 280 ° C. Outside the reaction temperature range, the transparency of the polymerized product is deteriorated.

At this time, the acetylated isosorbide is preferably added in an amount of 20 to 40 mol% based on the total diol component. When the content is less than 20 mol%, the transparency is poor. When the content is more than 40 mol%, mechanical properties are deteriorated.

It is also preferred that the polyethylene terephthalate polymer has a glass transition temperature of 100 to 120 ° C.

It is an object of the present invention to provide an isosorbide polyethylene terephthalate polymer which exhibits excellent mechanical properties while exhibiting high transparency by further introducing an isosorbide substituted with anhydride to acetic acid in the production of a polyethylene terephthalate polymer.

The method for producing an isosorbide polyethylene terephthalate polymer according to the present invention comprises the steps of reacting isosorbide and anhydrous acetic acid in the same amount to acetylate isosorbide; Preparing a slurry by mixing ethylene glycol (EG, Ethyleneglycol), terephthalic acid (TPA, Terephthalic acid) and the acetylated isosorbide; An esterification reaction step; And a polycondensation reaction step.

In this case, the melt polymer produced through the melt polymerization step has an intrinsic viscosity of 0.6 dl / g to 0.8 dl / g and a diethylene glycol content of 0.85 or less.

The isosorbide used in the present invention is a compound represented by the following formula (1).

[Chemical Formula 1]

The isosorbide represented by the above formula (1) is an environmentally-friendly diol compound derived from starch.

In the present invention, the isosorbide is substituted with acetic anhydride represented by the following formula 2 to increase the reactivity to copolymerize 20 to 40 mol% of isosorbide in the diol component.

(2)

The polyethylene terephthalate polymer according to the present invention is produced by copolymerizing an acid component and a diol component so that an acid moiety derived from an acid component and a diol moiety derived from a diol component It has a repeating structure.

The acid component used in the present invention is terephthalic acid, and the diol component is isosorbide substituted with anhydrous acetic acid and ethylene glycol.

Hereinafter, each step of the method for producing a high viscosity isosoboid poly (ethylene terephthalate) polymer according to the present invention will be described in detail.

In the process for preparing a high viscosity isosorbide polyethylene terephthalate polymer according to the present invention, the first step is a step of acetylating isosorbide by reacting the same equivalent amount of isosorbide with acetic anhydride. First, the same equivalent amount of isosorbide and anhydrous acetic acid are added and reacted at 130 to 140 ° C for 3 hours to acetylate isosorbide. Thereafter, terephthalic acid (TPA), ethylene glycol (EG) and the acetylated isosorbide are mixed to prepare a slurry. At this time, the molar ratio of the ethylene glycol and the acetylated isosorbide to the diol component terephthalic acid is preferably 1.1 to 1.2, and the acetylated isosorbide is preferably 20 to 40 mol% based on the total diol component . In the present invention, unreacted terephthalic acid can be present in the produced polymer in an amount of 50 ppm or less by using the molar ratio of the diol component and the acid component within the above range. If the amount of unreacted terephthalic acid exceeds 50 ppm in the polymer, the sacrifice of the yarn is deteriorated and it is difficult to manufacture high strength yarn. Further, since the glass transition temperature is increased by 1 占 폚 when the acetylated isosorbide is increased by 1 mole% in the diol component, the glass transition temperature becomes about 100 占 폚 when copolymerized by 20 mole% or more and 30 to 40 mole% The glass transition temperature is increased to 110 to 120 DEG C, so that it can be applied to water cups, bottles, food containers, and the like in which boiling water is required to be used. In addition, it can be applied to a tire cord having high heat resistance when it is made of fibers.

The antimony compound is added to the slurry in an amount of 150 to 250 ppm based on the antimony metal, and the esterification reaction and the condensation reaction are carried out. At this time, the antimony compound is preferably used as a polymerization catalyst in an amount of 150 to 250 ppm, preferably 150 to 220 ppm, based on the antimony metal. When the antimony compound is used in an amount exceeding 250 ppm based on the antimony metal, the filter of the spinning pack is clogged due to the precipitation of the antimony reducted metal, the pack use period is markedly shortened, and the stretchability is lowered and the workability is lowered. Further, when the antimony compound is used at less than 150 ppm based on the antimony metal, the polymerization rate can not be controlled only by the adjustment of the polymerization temperature and the degree of vacuum, and the polymerization rate becomes significantly slower, making commercial production difficult.

As the polymerization catalyst, a catalyst other than the antimony compound may be used in combination. Examples of other catalysts include Ti-based compounds and Al-based compounds. However, in this case, it is efficient for the efficiency of the antimony compound to be 80 wt% or more in the total polymerization catalyst to be added. In addition, metal compounds such as titanium dioxide and silica other than the polymerization catalyst may be added for the purpose of improving spinning, drawing workability, or other purposes. In this case, however, the metal compound is preferably added within a range not adversely affecting the heat resistance and strong development of the yarn made from the polymerized product produced according to the present invention. For example, the metal compound may be added in an amount of 150 ppm or less.

The reaction temperature in the esterification reaction is preferably 250 to 270 ° C, and the reaction time is preferably 3 to 4 hours. The polymerization temperature in the polymerization reaction is preferably 270 to 280 ° C, and the polymerization time is preferably 3 to 4 hours. When the esterification reaction is carried out at the above temperature and time, the esterification reaction rate becomes 98% or more. If the esterification reaction rate is not 98% or more, unreacted terephthalic acid is present in a large amount, and the polymer produced by the production method of the present invention is used to significantly reduce the fairness in the production of yarn, which is disadvantageous to the production of high strength yarn.

In the latter half of the polymerization, polymerization can be efficiently carried out with a relatively small amount of a polymerization catalyst by keeping the polymerizate in a final polymerization reactor under a high vacuum of 2.5 torr or less for 1.5 hours or more, preferably 2 hours or more. In the final polymerization reactor, if the vacuum is taken to be stronger than 2.5 torr or if the residence time is less than 1.5 hours, the reduced metal antimony and unreacted terephthalic acid can not be sufficiently removed and the remaining amount of metal antimony exceeds 5 ppm, unreacted terephthalic acid Resulting in an excess of 50 ppm, which is disadvantageous in the production of high strength yarn, strength development and heat resistance in the production of yarn using polymer.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The properties of the polymers prepared in the examples and comparative examples of the present invention were evaluated in the following manner.

(1) Viscosity

0.1 g of a polyethylene terephthalate polymer was added to a reagent (90 DEG C) mixed with phenol and 1,1,2,2-tetrachloroetal in a weight ratio of 6: 4 according to ASTM D 4603 for 90 minutes so as to have a concentration of 0.4 g / The solution was transferred to a Ubbelohde viscometer and maintained in a 30 ° C thermostat for 10 minutes. The drop number of the solution was obtained using a viscometer and an aspirator.

The values of RV (relative viscosity) and I.V. (intrinsic viscosity) were calculated by equations (1) and (2).

&Quot; (1) "

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

&Quot; (2) "

I.V. = 1/4 x [(R.V.-1) / C] + 3/4 (lnR.V./C)

(Where C represents the concentration (g / 100 ml) of the sample in the solution).

(2) Analysis of diethylene glycol (DEG) level

Aminolysis was performed using monoethanolamine and analyzed by GC. Specifically, 1 g of a polyethylene terephthalate polymer was taken, 3 ml of monoethanolamine was added thereto, and a cooler was attached, followed by completely decomposing by heating on a hot plate. After cooling, 20 ml of MeOH containing internal standard (1,6-hexanediol) and 10 g of terephthalic acid (TPA) were added and analyzed using GC. DEG standard curve was prepared using a MeOH solution containing the same internal standards and having DEG contents of 0, 0.05, 0.1 and 0.15%, respectively.

Example  One

Equal amounts of isosorbide and anhydrous acetic acid were added and reacted at 130 ° C for 3 hours to acetylate isosorbide. Thereafter, acetylated isosorbide and ethylene glycol / terephthalic acid were mixed at a molar ratio of 1.15: 1 to prepare a slurry. Wherein the acetylated isosorbide contained 20 mol% based on the total diol component of the acetylated isosorbide and ethylene glycol.

Antimony trioxide was added to the slurry in an amount of 190 ppm based on the antimony metal (based on the weight of ethylene glycol and terephthalic acid) and the esterification reaction was carried out at a polymerization temperature of 250 캜 for 3 hours. At this time, acetic acid flows out together with water. Finally, a polycondensation reaction was carried out at 270 DEG C for 3 hours to prepare an isosorbide polyethylene terephthalate polymer.

Example  2

The isosorbide polyethylene terephthalate polymer was prepared in the same manner as in Example 1 except that isosorbide was added in an amount of 40 mol% based on the total diol component.

Comparative Example  One

The isosorbide polyethylene terephthalate polymer was prepared in the same manner as in Example 1, except that 20 mol% of the non-acetylated isosorbide was added based on the total diol component.

Comparative Example  2

The isosorbide polyethylene terephthalate polymer was prepared in the same manner as in Example 1, except that the non-acetylated isosorbide was added in an amount of 40 mol% based on the total diol component.

Experimental Example  One

The glass transition temperature of the polyethylene terephthalate polymer prepared in Examples 1 and 2 and Comparative Examples 1 and 2 and the polyethylene terephthalate polymer prepared were first molded into an inlet of the preform and molded into a body and a bottom of the preform, The opening of the preform was crystallized in a crystalizer attached to a SRF-10/10 blow machine manufactured by Side Inc. to form a heat-resistant bottle, and the transparency of the bottle was measured using a haze meter (No. 206) manufactured by Toyo Seiki, Respectively.

division Example 1 Example 2 Comparative Example 1 Comparative Example 2 Transparency (Haze%) 1.8 1.1 2.3 2.1 Glass transition temperature (Tg, ° C)
[Measuring method: DSC] 100 120 92 98

As shown in Table 1, in Examples 1 and 2 using isosorbide substituted with anhydrous acetic acid, the reaction rate of isosbide involved in the polymerizate was higher than that of Comparative Examples 1 and 2 using general isosobide, And the transparency was excellent. Particularly, in comparison with Example 2 and Comparative Example 2, the isosorbide substituted with anhydrous acetic acid had a glass transition temperature of about 40 ° C and increased transparency because the reaction rate of the isosorbide was almost 100% In the case of isosobide, the reaction rate was less than 50%, and the increase of the glass transition temperature was small and the improvement of transparency was insufficient. It is believed that isosorbide is difficult to participate in reaction with terephthalic acid because of its high molecular weight compared to ethylene glycol.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Will be apparent to those skilled in the art. Accordingly, the scope of protection of the present invention should be defined in the appended claims and their equivalents.

Claims (4)

Reacting the same equivalent of isosorbide with acetic anhydride to acetylate isosorbide;
Mixing the acetylated isosorbide, ethylene glycol (EG), and terephthalic acid (TPA) to prepare a slurry;
An esterification reaction step of the slurry; And
A polycondensation reaction step; Wherein the isosorbide poly (ethylene terephthalate) polymer has a high transparency.
The method according to claim 1,
Wherein the acetylated isosorbide is added in an amount of 20 to 40 mol% based on the total diol component.
The method according to claim 1,
Wherein the polyethylene terephthalate polymer has a glass transition temperature of 100 to 120 ° C.
The method according to claim 1,
The reaction temperature of the isosorbide and the acetic anhydride is 130 to 140 캜,
The esterification reaction temperature is 250 to 270 캜,
Wherein the polycondensation reaction is carried out at a temperature of 270 to 280 占 폚.