KR20160073474A - Method for Preparing Polyester Polymer Having Heat Resistance and High Modulus and Polyester Fiber Made Thereof - Google Patents

Abstract

The present invention relates to a method for preparing a polyester polymer and a polyester thread prepared by the method, the method comprising the following steps of: mixing at least one dicarboxylic acid or an ester forming derivative thereof, at least one glycol or an ester forming derivative thereof and spiroglycol (SPG) at a certain ratio to prepare slurry and copolymerizing the resultant through esterification; and producing a copolymer with the oligomer after esterification through high vacuum in the presence of a polycondensation catalyst. By adding 2-15 mol% of SPG with respect to the acidic ingredient, the polyester polymer according to the present invention has an effect of increasing glass transition temperature and increasing strength to 15%. Also, the SPG-polyester prepared by the method is widely used as an industrial thread which requires high strength and high heat-resistance and also can be used for a tire code, a sheet belt, and an airbag.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a heat resistant high strength polyester polymer,

The present invention relates to a process for producing a heat-resistant high-strength polyester polymer having a glass transition temperature elevated and a strength of a yarn enhanced by adding a part of spiroglycols during polyester copolymerization, and a polyester yarn produced thereby.

In general, polyester, particularly polyethylene terephthalate (hereinafter referred to as PET), has excellent mechanical properties and good chemical properties such as chemical resistance and is widely used in fibers, films, and engineering plastics. Nonetheless, much research has been done in the related industry to make products superior to ordinary polyesters.

In this connection, studies have been conducted extensively on the use of other monomers instead of TPA (terephthalic acid) or other monomers in place of ethylene glycol in order to further enhance heat stability and strength, as compared with conventional polyesters. Among them, research on the use of a comonomer having inherent properties by retaining the ester group (-COO) of the polyester itself in order to increase the heat resistance using the copolymer polyester is the main one. Korean Patent Laid-Open Publication No. 10-2001-0008908 and Korean Patent Registration No. 10-0855694 disclose a technique for improving heat stability by using a polycarbodiimide.

However, in spite of a lot of studies to improve the physical properties of polyester, further research and development are still needed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide a method of producing a polyester polymer having remarkably improved heat stability and strength than a conventional polyester, .

According to one aspect of the present invention, there is provided a method for producing a dicarboxylic acid or its ester-forming derivative, at least one kind of glycol or an ester-forming derivative thereof, and a spiroglycol Spiroglycol, SPG) at a predetermined ratio to prepare a slurry, copolymerizing the slurry under an ester reaction, and subjecting the ester-terminated oligomer to a high vacuum under a polycondensation catalyst to produce a copolymer. .

[Chemical Formula]

In the method for producing a polyester polymer according to an embodiment of the present invention, the spiroglycol is added in an amount of 2 to 15 mol% based on the acid component.

In the method for producing a polyester polymer according to an embodiment of the present invention, the at least one dicarboxylic acid or an ester-forming derivative thereof may be at least one selected from the group consisting of terephthalic acid, isophthalic acid, biphenyldicarboxylic acid, 1,4-naphthalenedicarboxylic acid Aromatic dicarboxylic acids such as 1,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid and the like, and ester-forming derivatives thereof, 1,4-cyclohexane dicarboxylic acid, A dicarboxylic acid, and an alkane dicarboxylic acid having 2 to 6 carbon atoms.

In the method for producing a polyester polymer according to an embodiment of the present invention, the at least one kind of glycol is selected from the group consisting of ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3- Alicyclic diols such as butanediol, 1,5-pentanediol and 1,6-hexanediol, alicyclic diols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol, bisphenol A and bisphenol S An ethylene oxide or propylene oxide adduct of an aromatic diol with an aromatic diol, and a halogen-substituted compound thereof.

Another aspect of the present invention for achieving the above object is a polyester yarn produced by solid phase polymerization or direct spinning of a polyester polymer produced by the above-mentioned production method.

The process for producing a polyester polymer according to the present invention has the effect of increasing the glass transition temperature and increasing the strength to 15% by adding 2 to 15 mol% of spiroglycols (SPG) to the acid component. Due to such effects, the SPG-polyester according to the present invention is widely used as an industrial yarn requiring high strength and high heat resistance, and can be used for a tire cord, a seat belt, an airbag, and the like.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to examples and the like. In the following description of the present invention, a detailed description of known general functions or configurations will be omitted.

The present invention relates to a process for producing a heat-resistant high-strength polyester polymer having a glass transition temperature elevated and a strength of a yarn enhanced by adding a part of spiroglycols during polyester copolymerization, and a polyester yarn produced thereby.

A method for producing a polyester polymer according to the present invention comprises reacting at least one dicarboxylic acid or an ester forming derivative thereof with at least one glycol or an ester forming derivative thereof and Spiroglycol (SPG) represented by the following formula: To prepare a slurry, copolymerizing the slurry under an ester reaction, and subjecting the ester-terminated oligomer to a high-vacuum under a polycondensation catalyst to produce a copolymer.

[Chemical Formula]

The spiroglycols are preferably added in an amount of 2 to 15 mol% based on the acid component. If the content of spiroglycols is high, the glass transition temperature rises and the heat resistance is excellent, but an amorphous polymer is formed, which is a factor for inhibiting the strength, and when the spiroglycol content is too low, the effect is not exhibited .

The dicarboxylic acid or its ester-forming derivative used in the method for producing the polyester polymer of the present invention includes terephthalic acid, isophthalic acid, biphenyldicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalene Aromatic dicarboxylic acids such as dicarboxylic acid and 2,6-naphthalene dicarboxylic acid, and ester-forming derivatives thereof, and alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid and alicyclic dicarboxylic acids having 2 to 6 carbon atoms Alkane dicarboxylic acid, and the like.

In order not to significantly lower the economical efficiency and the physical properties of the polyester, it is preferable that the molar ratio of terephthalic acid to the total dicarboxylic acid is 70% or more. Preferably, terephthalic acid is used in an amount of 100 mol%. If it is less than 70 mol%, the melting temperature or the glass transition temperature lowers and the moldability deteriorates, and when the expensive copolymerizable monomer is used, the manufacturing cost becomes too high.

Examples of the glycol component include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6- Alicyclic diols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol, aromatic oxides such as bisphenol A and bisphenol S, and aromatic oxides such as ethylene oxide or propylene oxide, Substituted compounds of halogen. In order to express the properties of the polymer, it is preferable that the molar ratio of ethylene glycol in the entire polymer glycol component is 70% or more. If it is lower than this, molding problems may occur.

As the polymerization catalyst to be used in the present invention, a catalyst used for general polyester polymerization can be used. Antimony compounds such as antimony trioxide, antimony triacetate and antimony triglycolate, titanium compounds such as titanium tetrabutylate and titanium tetraisopropylate, zinc compounds such as zinc acetate tin compounds such as zinc acetate, germanium dioxide, monobutyl tin oxide or dibutyl tin oxide, manganese acetate and the like can be used. The content of these catalysts is preferably 10 to 1000 ppm based on the metal content with respect to the weight of the polymer.

If the catalyst is less than 10 ppm, the activity of the catalyst is too low. If it is more than 1000 ppm, these catalysts not only cause foreign matters but also increase manufacturing costs.

The resin composition of the present invention may further contain stabilizers, coloring agents, and the like as other additives. As the stabilizer usable in the present invention, phosphoric acid, trimethylphosphate, triethylphosphate, triethylphosphonoacetate and the like can be exemplified, and the addition amount thereof is preferably 10 to 100 ppm based on the weight of the final polymer based on the amount of the phosphorus . If the addition amount of the stabilizer is less than 10 ppm, it is difficult to obtain a desired bright color. If the addition amount exceeds 100 ppm, a desired high polymerization degree can not be attained.

The coloring agent usable for improving color in the present invention may include conventional coloring agents such as cobalt acetate and cobalt propionate. The amount of the coloring agent added is preferably 0 to 100 ppm based on the weight of the final polymer.

In addition, materials known as antioxidants in the present invention can be used without limitation. Examples thereof include phenol type, phosphite type, thioether type, and amine type.

Another aspect of the present invention relates to a polyester yarn having excellent heat resistance and strength, which is produced by solid-state polymerization or direct polymerization of a polyester polymer produced by the above-described method.

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 present invention.

< Example  1>

8.3 kg of terephthalic acid and 4.0 kg of ethylene glycol were reacted at 260 ° C. for 3 hours, and 1.5 kg of spiroglycol was added to the molten PET oligomer. The reaction mixture was reacted at 250 ° C. for 1 hour in a nitrogen atmosphere under a nitrogen atmosphere to obtain a copolymerized oligomer . The polycondensation reaction was carried out in a polycondensation reactor over 200 minutes under a reduced pressure of 1 mmHg or less under a reduced pressure until the reaction temperature reached 270 ° C.

< Example  2>

A polyester polymer was prepared by the same procedure as in Example 1, except that the amount of spiroglycol added was 2.3 kg.

< Example  3>

A polyester polymer was prepared in the same manner as in Example 1, except that 0.75 kg of spiroglycol was added.

< Comparative Example  1>

A polyester polymer was prepared by the same procedure as in Example 1 except that spiroglycol was not added.

< Comparative Example  2>

A polyester polymer was prepared by the same procedure as in Example 1, except that the amount of spiroglycol added was 3.0 kg.

< Comparative Example  3>

A polyester polymer was prepared by the same procedure as in Example 1 except that the amount of spiroglycol added was 4.6 kg.

The results of the physical properties of the polyester polymer prepared according to the above Examples and Comparative Examples are shown in Table 1 below.

Input material Fila IV (dl / g) Tg (C) Strength (g / d) Draw
Ratio Example 1 TPA (1.0) EG (1.3) SPG (0.10) 0.95 84 8.4 2.0 Example 2 TPA (1.0) EG (1.3) SPG (0.15) 0.98 90 8.6 2.2 Example 3 TPA (1.0) EG (1.3) SPG (0.05) 0.97 80 8.3 2.2 Comparative Example 1 TPA (1.0) EG (1.3) SPG (0.00) 1.05 78 8.3 2.4 Comparative Example 2 TPA (1.0) EG (1.3) SPG (0.20) 0.85 96 6.3 1.4 Comparative Example 3 TPA (1.0) EG (1.3) SPG (0.30) 1.02 105 5.2 1.3

The obtained polyester was vacuum-dried at 130 ° C for 12 hours, and then vacuum-heated at 220 ° C for 13 hours to raise the intrinsic viscosity to 1.0 level. SPG-PET having such a high viscosity was produced by high-strength yarn after multi-stage stretching using the spinning equipment described in Korean Patent No. 2001-0067459.

(1) Intrinsic viscosity (I.V.)

Phenol and 1,1,2,3-tetrachloroethane in a weight ratio of 6: 4 was dissolved in a reagent (90 ° C) for 90 minutes so that the concentration of the sample became 0.4 g / 100 ml

The solution was transferred to a Ubbelohde viscometer and maintained at 30 ° C in a thermostatic chamber for 10 minutes. The drop number of the solution was obtained using a viscometer and an aspirator.

The number of drops of solvent was determined by the same method, and RV and IV values were calculated by the following equations (1) and (2).

Equation  One

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

Equation  2

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

In the above equation, C represents the concentration (g / 100 ml) of the sample in the solution.

(2) the strong person

Under the conditions of a sample length of 250 mm, a tensile speed of 300 mm / min, and a rate of 80 turns / m under standard conditions (20 ° C, 65% relative humidity) according to ASTM D 885 using an Instron 5565 (Instron, USA).

(3) Measurement of glass transition temperature (Tg):

The glass-rubber transition temperature (Tg) was measured using a product of Perkin-Elmer (Model DSC 7), the polyester resin was annealed at 300 ° C for 5 minutes, quenched to room temperature, The Tg temperature is measured by a second scan at 10 ° C / min.

As can be seen from the above Table 1, the polyester copolymers (Examples 1 to 3) according to the present invention, to which spiroglycol was added, exhibited glass transition as compared with the polyester copolymer (Comparative Example 1) to which no spiroglycol was added Temperature and strength are increased. On the other hand, in the case of adding spiroglycol in an excess amount (Comparative Examples 2 and 3), it is found that the glass transition temperature is increased but the stretching is difficult with the amorphous polymer and the strength is rapidly lowered.

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 exemplary embodiments. This will be obvious.

Claims (7)

At least one dicarboxylic acid or an ester-forming derivative thereof, at least one glycol or an ester-forming derivative thereof, and spiroglycol (SPG) represented by the following formula are mixed at a predetermined ratio to prepare a slurry, &Lt; / RTI &gt; And
And subjecting the ester-terminated oligomer to a high vacuum under a polycondensation catalyst to produce a copolymer.
[Chemical Formula]

The method for producing a polyester polymer according to claim 1, wherein the spiroglycol is added in an amount of 2 to 15 mol% based on the acid component.
The method of claim 1, wherein the at least one dicarboxylic acid or ester-forming derivative thereof is selected from the group consisting of terephthalic acid, isophthalic acid, biphenyldicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid Aromatic dicarboxylic acids such as 2,6-naphthalene dicarboxylic acid and the like, and ester-forming derivatives thereof, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, alkane having 2 to 6 carbon atoms Dicarboxylic acid. &Lt; RTI ID = 0.0 &gt; 8. &lt; / RTI &gt;
The method of claim 1, wherein the at least one glycol is selected from the group consisting of ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, , And 6-hexanediol; alicyclic diols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol; aromatic diols such as bisphenol A and bisphenol S; and aromatic diols such as ethylene oxide or propylene oxide Adducts thereof, and halogen-substituted compounds thereof. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt;
The method for producing a polyester polymer according to claim 3, wherein the dicarboxylic acid is terephthalic acid.
The process for producing a polyester polymer according to claim 4, wherein the glycol is ethylene glycol.
A polyester yarn produced by solid-state polymerization or direct spinning of a polyester polymer according to the production method according to any one of claims 1 to 6.