KR101959331B1 - Process for preparing non-toxic Polyethylene terephtalate yarn - Google Patents

Abstract

The present invention relates to a manufacturing method of non-toxic polyethylene terephthalate yarn, which comprises: a step of making ethyleneglycol (EG) and terephthalic acid (TPA) into a slurry form; an esterification reaction step of the slurry; a step of producing a polyethylene terephthalate (PET) polymer by a polycondensation reaction; and a step of spinning and stretching the PET polymer to produce yarn. The PET yarn manufacturing method puts a titanium-based catalyst at the beginning of the polycondensation reaction, and puts titanium dioxide or carbon black additives at the end of the polycondensation reaction. The present invention provides industrial PET yarn and a seat belt including the same wherein the industrial PET yarn has excellent appearance and properties and does not have toxicity by adding a titanium-based catalyst and additives instead of antimony in a step of polymerizing PET.

Description

Technical Field [0001] The present invention relates to a process for preparing a non-toxic polyethylene terephthalate yarn,

TECHNICAL FIELD The present invention relates to industrial polyethylene terephthalate yarn excellent in appearance and physical properties, and having no toxicity, and a method for producing the same, by introducing a titanium-based catalyst and an additive instead of antimony conventionally used in polyethylene terephthalate (PET).

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 a condensation polymerization method, wherein antimony trioxide or antimony acetate is used most commercially as a catalyst for the polymerization reaction.

The polyester yarn for seat belts, which is generally used up to now, uses high purity antimony trioxide (Sb2O3), which is a heavy metal element, as a polymerization catalyst in the production of chips, and usually 150 to 300 ppm is used.

When polyesters are polymerized using an antimony catalyst, the color of the resin is excellent and the activity is high during the reaction, which is advantageous because of its high productivity. However, antimony is regulated as harmful to the human body due to its toxicity, When used in food packaging, the amount of antimony leaching is strictly controlled by law, and in some advanced countries, the use of antimony catalysts is gradually being reduced.

The International Organization for Research on Cancer (IARC) of the World Health Organization (WHO) classifies antimony as a human carcinogen. Currently, regulations on the use of antimony in Europe are accelerating, and Seat Belt , It is necessary to reduce the antimony content. However, since the residual catalyst in the production of the high strength yarn is 10 to 15 times lower than that of the antimony catalyst, The strength is lowered and the appearance defect phenomenon occurs.

An object of the present invention is to provide an industrial polyethylene terephthalate yarn which is excellent in appearance and physical properties and is not toxic by introducing a titanium-based catalyst and an additive instead of antimony in the production of polyethylene terephthalate yarn.

In order to accomplish the above object, the present invention provides a method for manufacturing a semiconductor device, comprising: slurrying ethylene glycol (EG) and terephthalic acid (TPA);

An esterification reaction step of the slurry;

Preparing a polyethylene terephthalate polymer by a polycondensation reaction; And

Spinning the polyethylene terephthalate polymer and stretching to produce a yarn,

Wherein the titanium-based catalyst is introduced at the beginning of the polycondensation reaction, and titanium dioxide or a carbon black additive is added to the end of the polycondensation reaction.

Another suitable embodiment of the present invention is a process for producing a polyethylene terephthalate masterbatch comprising mixing and melting a polyethylene terephthalate masterbatch comprising a titanium dioxide or carbon black additive and a polyethylene terephthalate chip or by directly melting a titanium dioxide or carbon black additive and a polyethylene terephthalate chip, ; And

And a step of spinning the polymer by spinning nozzles, multi-step stretching, and winding to produce a polyethylene terephthalate yarn. The present invention also provides a method for producing a non-toxic polyethylene terephthalate yarn.

In another preferred embodiment of the present invention, the additive has an average particle diameter of 10 to 50 nm and an additive amount of 100 to 5000 ppm. In the initial stage of the polycondensation reaction, the titanium- And 20 ppm is added.

The present invention relates to a method for producing a polyethylene terephthalate (PET) yarn, comprising the steps of charging a titanium-based catalyst and an additive instead of antimony in the step of polymerizing polyethylene terephthalate to produce an industrial polyethylene terephthalate A yarn and a seat belt including the same.

The present invention provides a method for producing a non-toxic polyethylene terephthalate yarn.

A method for preparing a non-toxic polyethylene terephthalate yarn according to one embodiment includes a step of slurrying ethylene glycol (EG, Ethyleneglycol) and terephthalic acid (TPA, terephthalic acid), an esterification reaction step of the slurry, To produce a polyethylene terephthalate polymer, and spinning the polyethylene terephthalate polymer and stretching to produce a yarn.

At this time, it is preferable to add a titanium-based catalyst at the beginning of the polycondensation reaction and add an additive such as titanium dioxide or carbon black to the end of the polycondensation reaction.

In the present invention, the titanium-based catalyst used in the early stage of the polycondensation reaction is titanium alkoxide and is characterized by being made of a titanium-oxygen atom-organic substituent (R) structure. The titanium alkoxide is most preferably titanium (IV) isopropoxide (Ti {OCH (CH ₃ ) ₂ } ₄ ).

The titanium alkoxide may be selected from the group consisting of titanium methoxide, titanium ethoxide, titanium propoxide, titanium butoxide and the like depending on the type of the organic substituent (R) But is not limited thereto.

The content of the titanium-based catalyst of the present invention is 10 to 20 ppm. When the content of the titanium-based catalyst is less than 10 ppm, the effect of the reactivity is low, so that a sufficient molecular weight can not be obtained. When the content is more than 20 ppm, pyrolysis and yellow coloration may occur.

Also, the antimony catalyst may be added in an amount of 0 to 50 ppm in consideration of the reactivity of the titanium-based catalyst at the beginning of the polycondensation reaction, but the present invention is not limited thereto.

The present invention is characterized in that titanium dioxide or a carbon black additive is added to the end of the polycondensation reaction. The particle size of the titanium dioxide added at this time is preferably 10 to 50 nm, more preferably 10 to 20 nm. The dosage is preferably 100 to 5000 ppm, more preferably 100 to 2000 ppm. When the size of the titanium dioxide is less than 10 nm, the nucleus reaction becomes uneven and the quality of the yarn is deteriorated due to insufficient function as a nucleating agent. When the size exceeds 50 nm, the crystallization rate of the reaction is not affected. The appearance quality of the yarn is deteriorated.

If the amount of the titanium dioxide is less than 100 ppm, the nucleus reactivity is lowered during the stretching process, and if it exceeds 5000 ppm, the physical properties are lowered.

In the case of the carbon black additive, the particle size is preferably from 10 to 50 nm, more preferably from 10 to 20 nm. The dosage is preferably 100 to 5000 ppm, more preferably 100 to 3000 ppm. If the size of the carbon black is less than 10 nm, the function as a nucleating agent can not be sufficiently performed and the reaction becomes uneven and the quality of the yarn becomes poor. When the size exceeds 50 nm, the crystallization rate of the reaction is not affected, The appearance quality of the yarn is deteriorated.

When the amount of the carbon black is less than 100 ppm, the reactivity is lowered, and when the amount is more than 5000 ppm, the productivity is lowered.

Meanwhile, the non-toxic polyethylene terephthalate raw material of the present invention can be obtained by mixing and melting a polyethylene terephthalate master batch and a polyethylene terephthalate chip containing titanium dioxide or a carbon black additive, or by directly melting a titanium dioxide or carbon black additive and a polyethylene terephthalate chip A step of preparing a polymer, and a step of spinning the polymer by spinning nozzles, multi-step stretching, and then winding to produce a polyethylene terephthalate yarn, which can be produced by a method of producing a non-toxic polyethylene terephthalate yarn .

Here, the titanium dioxide or carbon black additive is the same as described above.

In this case, the master batch chip uses a twin-screw extruder having an L / D ratio of 28 or more in consideration of the effect of kneading. The operating temperature of the axial extruder is set at 250 ° C to 290 ° C. The mixture melt-kneaded through a twin-screw extruder is passed through a cooling water bath maintained at 25 ° C to 30 ° C, solidified, and then chips are formed using a chip cutter.

In the present invention, the polyethylene terephthalate polymer or the master batch and the polyethylene terephthalate chip are mixed and melted, or the additive and the polyethylene terephthalate chip are directly melted, are melted and spun according to a general process well known in the textile industry, Can be manufactured.

The method for producing the polyethylene terephthalate yarn according to the present invention will be described in detail as follows.

In the spinning step, the polyethylene terephthalate chip is melt-spun through a pack and a nozzle at a temperature of 280 to 310 ° C. In the present invention, the spinning polymer is preferably mixed evenly and the uniformity of melt viscosity of the polymer is increased A static mixer or the like may be installed in the upper part of the pack.

In the solidification cooling step of the present invention, the molten discharge yarn generated in the spinning step is solidified by passing through a cooling zone. If necessary, a heating device may be installed at a distance from the nozzle directly below the nozzle to the starting point of the cooling zone . This zone is referred to as the delayed cooling zone or heating zone, which may have a length of 100 to 800 mm and a temperature of 200 to 400 ° C. In the cooling zone, an open quenching method, a circular closed quenching method, and a radial outflow quenching method may be applied according to a method of blowing cooling air, but the present invention is not limited thereto . Then, the solidified discharged yarn passing through the cooling zone can be oiled to 0.3 to 2.0% by the emulsion applying device.

In the stretching step of the present invention, the yarn passing through the feeding roller is wound in a multi-stage manner while passing a series of stretching rollers by a separate drawing process after the unstretched yarn is once drawn, or preferably by a spin draw process The final drawn filament is obtained by stretching, wherein the temperature of the second-stage stretching is adjusted to 100 to 210 占 폚. More specifically, a first drawing step is first performed at a rate of 1 to 10% free draw, followed by a first drawing step at 1.2 to 7 times at 80 to 200 캜, a second drawing step at 1.2 to 2.0 times at 130 to 200 캜, And the steam jet method may be applied to increase the uniformity of the high-ratio stretching during the first-stage stretching. Then, according to a conventional method, the drawn yarn can be heat set at a temperature of 200 to 260 ° C and relaxed to 0.5 to 15%.

The radial emulsion used in the production of the polyethylene terephthalate yarn of the present invention is preferably a radial emulsion having a heat loss rate of 1 to 10% measured at a temperature of 298 ° C measured with a TGA apparatus in a state in which solvent and moisture are removed. A radial emulsion having a heating loss rate of less than 1% up to 298 캜 is difficult to exist, and when a radiant emulsion having a heating loss rate of 10% or more is applied, the effect of improving the strength retention rate after a high temperature heat treatment is not sufficient.

As described above, the polyethylene terephthalate multifilament yarn produced by the present invention can be used in fabrics and the like, but can be used not limited to seat belts, industrial webbing, ropes, and the like.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are intended to illustrate the present invention and are not to be construed as limiting the scope of the present invention. The properties of the yarns prepared in Examples and Comparative Examples of the present invention were evaluated in the following manner.

(a) Strength (tensile strength) (g / d)

The yarn was allowed to stand for 24 hours in a standard temperature condition, i.e., a constant temperature and humidity room at a temperature of 25 DEG C and a relative humidity of 65%, and then measured by a tensile tester by the method of ASTM D-885.

(b) Determination of percent defects (%) in the midsole (%) and fracture strength at a load of 4.5 g / d

According to the ASTM D885 standard, the stiffness of the PET stretch yarn at a load of 4.5 g / d and a tensile strength at break was measured using a universal tensile tester.

(c) Method of measuring shrinkage percentage

The shrinkage of the yarn is measured in a test light shrinkage tester at 180 ° C for 2 minutes under a condition of 0.05 gf / denier load.

(d) Method of measuring metal

According to the ASTM D1976 (02) method, the metal content of the yarn was measured.

≪ Example 1 >

A slurry of 50 parts by weight of ethylene glycol was added to an esterification reactor in an amount of 100 parts by weight of terephthalic acid and the reaction was allowed to proceed while allowing water to flow out of the reaction vessel at a pressure of 0.5 torr at 250 DEG C for 4 hours to obtain bis Bis (2-hydroxyethyl) terephthalate] was prepared. At this time, 300 ppm of a phosphorus-based heat stabilizer was added at the end of the esterification reaction. Thereafter, 15 ppm of titanium (IV) isopropoxide (Ti {OCH (CH ₃ ) ₂ } ₄ ) as a polymerization catalyst was added at the initial stage of the condensation reaction and the temperature was raised from 250 ° C. to 285 ° C. at 60 ° C./hr. At the same time, the pressure was reduced to 0.5 torr to carry out a polycondensation reaction, and a polycondensation reaction was carried out by adding 300 ppm of a titanium dioxide additive having an average particle size of 15 nm to the end of the polycondensation reaction.

The polyethylene terephthalate polymer was spun using a 144-hole nozzle and subjected to a stretching step to produce a polyethylene terephthalate yarn.

≪ Example 2 >

A yarn was produced in the same manner as in Example 1, except that 2000 ppm of titanium dioxide was added as an additive instead of 300 ppm of titanium dioxide.

≪ Example 3 >

A yarn was prepared in the same manner as in Example 1, except that 500 ppm of carbon black having an average particle size of 15 nm was used instead of titanium dioxide as an additive.

<Example 4>

A yarn was prepared in the same manner as in Example 1, except that 3000 ppm of carbon black having an average particle size of 15 nm was added instead of titanium dioxide as an additive.

&Lt; Comparative Example 1 &

A slurry of 50 parts by weight of ethylene glycol was added to an esterification reactor in an amount of 100 parts by weight of terephthalic acid and the reaction was allowed to proceed while allowing water to flow out of the reaction vessel at a pressure of 0.5 torr at 250 DEG C for 4 hours to obtain bis Bis (2-hydroxyethyl) terephthalate] was prepared. At this time, 300 ppm of a phosphorus-based heat stabilizer was added at the end of the esterification reaction. Thereafter, 230 ppm of the antimony catalyst as a polymerization catalyst was added at the initial stage of the polycondensation reaction, the temperature was raised from 250 ° C. to 285 ° C. at 60 ° C./hr and the pressure was reduced to 0.5 torr to conduct a polycondensation reaction. A titanium dioxide additive having an average particle size of 250 nm was charged at 300 ppm after the reaction to produce a polymer.

The polyethylene terephthalate polymer was spun using a 144-hole nozzle and subjected to a stretching step to produce a polyethylene terephthalate yarn.

&Lt; Comparative Example 2 &

Antimony instead of titanium (IV) isopropoxide (Ti { OCH (CH 3) 2} 4) A yarn was prepared in the same manner as in Comparative Example 1 except that the catalyst was added (15 ppm).

division Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 catalyst
(ppm) antimony - - - - 230 - titanium (IV) isopropoxide (Ti { OCH (CH 3) 2} 4 15 15 15 15 - 15 additive
(ppm) TiO2
(Size: 250 nm) - - - - 300 300 TiO2
(Size: 15 nm) 300 2000 - - - - Carbon Black (Size: 15 nm) - - 500 3000 - - basic
Properties Strength (g / d) 9.4 9.2 8.1 8.2 9.4 9.0 Doubt (%) 16.6 15.4 16.4 16.5 16.5 14.6 Shrinkage (%) 9.1 9.0 9.0 9.1 9.1 9.0 Yarn defect (fluff) Good Good Good Good Good Bad

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, Various modifications and variations are possible within the scope of the claims

Claims (5)

Slurrying of ethylene glycol (EG, Ethyleneglycol) and terephthalic acid (TPA, terephthalic acid);
An esterification reaction step of the slurry;
Preparing a polyethylene terephthalate polymer by a polycondensation reaction; And
Spinning the polyethylene terephthalate polymer and stretching to produce a yarn,
At the initial stage of the polycondensation reaction, 10 to 20 ppm of a titanium-based catalyst is added, titanium dioxide or a carbon black additive is added to the end of the polycondensation reaction,
Wherein the additive has an average particle diameter of 10 to 50 nm and an input amount of 100 to 5000 ppm. &Lt; RTI ID = 0.0 &gt; 8. &lt; / RTI &gt;
delete delete delete A seat belt comprising a non-toxic polyethylene terephthalate yarn produced by the manufacturing method according to claim 1.