JPS6065113A - Preparation of antistatic polyester yarn - Google Patents

Abstract

PURPOSE:The titled yarn having extremely improved antistatic properties with easy chip formation, by blending an ordinary polyester with a polyethylene terephthalate modified with a polyalkylene glycol by a static blender stepwise, diluting the polyester, processing it into yarn. CONSTITUTION:Just before completion of polymerization of polyester comprising ethylene terephthalate as a main repeating unit, 60-90wt% polyalkylene glycol is added to the polymerizer 1 to give a modified polyester, to which an ordinary polyester having no polyalkylene glycol is fed by the melt extruder 4, these polyesters are mixed and diluted by the static blender 3, to give the master polyester A having 30-60wt% polyalkylene glycol. This polyester is reblended or combined with the ordinary polyester B by the static blender 7 of the spinneret pack 5 in such a way that the content of the polyalkylene glycol in the final product is 1.0-10.0wt%, and extruded into yarn to give the desired yarn.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing modified polyester fibers having antistatic properties, and its purpose is to significantly reduce the generation of static electricity characteristic of synthetic fibers. It is an object of the present invention to provide a raw yarn which has good comfort when made into a fabric.

Polyester, especially polyethylene terephthalate fiber, has a high degree of crystallinity and a high softening point, and has many advantages not found in other synthetic fibers, such as 1 strength elongation, chemical resistance, and weather resistance. It is increasingly being used not only for general purposes but also for industrial material applications. However, despite the above-mentioned advantages, it also has disadvantages such as relatively poor dyeability and being easily charged with static electricity. The former drawback has almost been solved through the copolymerization of easily dyeable third components or the development of dyeing processing technology, but the latter drawback, that is, the generation of static electricity, is important not only for clothing but also for interior applications such as carpets. There is a strong demand for a solution to this problem when polyester is used.

Conventionally, as a typical method for antistatic technology for polyester fibers, there has been a method of blending a hydrophilic polyalkylene glycol with polyester, and many proposals have not been made so far.

For example, Japanese Patent Publication No. 46-7213 proposes a method of blending polyester containing 10 to 60 weight percent polyalkylene glycol with ordinary polyester. However, in this method, the concentration of the polyalkylene glycol component relative to the polyester component in the initial stage is relatively low, so that the final product does not exhibit sufficient antistatic performance. This tendency was even more remarkable because the mixture and dilution with ordinary polyester was carried out using an extruder type kneader.

Oh, in Japanese Patent Publication No. 47-29183, the molecular weight is 9.
A method has been proposed in which a block polyetherester obtained by co-condensing more than 60% by weight and less than 90% by weight of polyalkylene glycol of 000 or more is blended with ordinary polyester. Although this method is improved in that the concentration of the polyalkylene glycol component is high in the first stage, it is possible to combine the polyester with a high concentration of the polyalkylene glycol component at once using an extruder-type mixer that has a good kneading effect. However, since the polyalkylene glycol component of high concentration is mixed and diluted, the dispersion of the polyalkylene glycol component at a high concentration is too rapid, which actually deteriorates the antistatic performance. Also, when mixing and diluting using an extruder type mixer.

Generally, a method is adopted in which polyester containing polyalkylene glycol is made into chips and then normal polyester chips are mixed with the core chips. There was a problem that cut chips were likely to occur.

The present inventors overcame the drawbacks of the prior art and conducted intensive studies on a method for manufacturing polyester fiber containing polyalkylene glycol with excellent antistatic properties. The final product is obtained by first mixing and diluting the polyester with an ordinary Bo1j ester to a medium content of K, and then subjecting it to similar mixing and dilution or compound dilution, and performing the mixing and dilution using a static mixer. The present inventors have discovered that even if the content of polyalkylene glycol in the polyalkylene glycol is a conventionally known content, extremely excellent antistatic performance is exhibited, and the present invention has been completed.

That is, the present invention relates to a modified polyester obtained by blending polyalkylene glycol in an amount of more than 60% by weight and less than 90% by weight before the completion of polymerization of a polyester having ethylene terephthalate as a main repeating unit, and a normal polyester containing no polyalkylene glycol. A master polyester having a proportion of polyalkylene glycol of 30 to 60% by weight is obtained by mixing and diluting the polyester with a static mixer to obtain a master polyester having a polyalkylene glycol content of 30 to 60% by weight.Then, the master polyester and the ordinary polyester are mixed to form a final product polyalkylene glycol. The gist of this invention is to provide a method for producing antistatic polyester fibers, which comprises mixing or compounding using a static mixer again to have a content of 1.0 to 10.0% by weight, and then spinning the fibers.

51 The usual polyester in the present invention is generally polyethylene terephthalate consisting of terephthalic acid and ethylene glycol, but it may also be one copolymerized with a third component of up to about 20 molar proportions. It doesn't work. Examples of such copolymer components include isophthalic acid, 5
-Sodium sulfoisophthalic acid, naphthalene dicarboxylic acid.

Aromatic dicarboxylic acids such as diphenyldicarboxylic acid.

Aliphatic dicarboxylic acids such as adipic acid and sebacic acid.

Oxy acids such as p-oxybenzoic acid and β-hydroxyethoxybenzoic acid, trimethylene glycol.

Dioxy compounds such as 1,4-butanediol and bisphenol A can be mentioned. These may be used alone or in combination of two or more.

The polyalkylene glycol used in the present invention has a molecular weight of 500 to 10,000. Light weight is 100
0-7000 polyethylene glycol.

Refers to polyethers such as polypropylene glycol,
In particular, polyethylene glycol having a molecular weight of 2,000 to 5,000 is preferably used.

6- In the present invention, the blending amount of the polyalkylene glycol is 1.0 to 10.0 in the final product as described below.
Although it is necessary that the amount is 8% by weight, the blending method and conditions are particularly important.

That is, first, 60% by weight of polyalkylene glycol
Synthesize a modified polyester compounded at a relatively high concentration of 90% by weight or less, and mix and dilute the modified polyester with a normal polyester so that the proportion of the polyalkylene glycol becomes 30 to 60% by weight. , it is necessary to obtain a master polyester having a medium blending ratio of polyalkylene glycol of 30 to 60% by weight. In this case, it is important to perform the mixing and dilution using a static mixer rather than using a kneader such as an extruder type kneader.

In the present invention, if the content of polyalkylene glycol in the modified polyester is 60% by weight or less, a sufficient effect of improving antistatic properties will not be exhibited, which is not preferable.

In other words, according to the studies of the present inventors, when trying to impart antistatic properties to polyester using polyalkylene glycol, the concentration of (1) alkylene glycol in the first synthesized modified polyester is extremely important; When mixed and diluted.

Even if the concentration of the mixture as a whole decreases according to the dilution ratio, it is necessary to adopt a mixing method that locally causes the initially high concentration components to exist as layered blocks of a certain size. There was found. If the concentration of polyalkylene glycol in the modified polyester is less than 60% by weight, sufficient antistatic performance will not be exhibited.

On the other hand, if the concentration of polyalkylene glycol in the modified polyester is greater than 90% by weight, it is not preferable because not only will the thermal stability become extremely unstable, but the miscibility with ordinary polyesters will be too inhibited. .

In the present invention, the mixing dilution in the first stage is as follows.

In order for the polyalkylene glycol-rich portion to take on the properties described above, it is necessary to use a static mixer. In this case, it is even more advantageous because the mixture can be mixed in the molten state without needing to be made into chips.

In the present invention, the content of polyalkylene glycol in the master polyester after mixing and dilution in the first stage is 30
It is necessary to control the content to 60% by weight. If you try to dilute a highly concentrated modified polyester to 1.0 to 100% by weight at once, the mixing ratio of normal polyester at the time of dilution will be relatively high, making it difficult to mix appropriately with the properties described above. It will become. Furthermore, even if the dilution is attempted by compounding, smooth spinning will not be possible for the same reason.

Polyalkylene gel +1 obtained by first-stage mixing and dilution under the conditions and method described above in the present invention: I −
The master polyester containing 30 to 60% of /l/ has a polyalkylene glycol content of 1 in the final product.
．． It is necessary to perform a second stage of dilution by mixing or compounding so that the amount becomes 0 to 10.0% by weight. In this case, if the second stage dilution is performed by mixing, it is necessary to use a static mixer for the reasons already mentioned.

The content of polyalkylene glycol in the final product is 1.0
When the weight is less than t%, sufficient antistatic properties are not exhibited, which is not preferable. On the other hand, if the content of polyalkylene glycol in the final product exceeds 10.0% by weight, the excellent physical and chemical properties inherent to polyester begin to deteriorate rapidly, which is also undesirable.

Note that, unlike the first stage, the proportion of polyalkylene glycol in the master polyester is reduced to 30 to 60% by weight in the second stage of mixing.
It is also possible to make it into a chip.

FIG. 1 is a schematic diagram showing an example of a mixing system used in the present invention, and is an example in which antistatic polyester fibers are continuously spun without chipping the master polyester.

The modified polyester synthesized in the polymerization tank 1 is mixed and diluted with ordinary 10-polyester melted using a separate melt extruder 4 in a static mixer 3 installed in the middle of the pipeline 2, and further mixed and spun. In the spinneret pack 5 or composite spinneret pack 5' (not shown), it is again diluted with the usual polyester supplied from 4 and spun as a mixed yarn or composite yarn 6.

FIG. 2 shows an example of the spinneret pack, in which a second stage of mixing and dilution is performed by a static mixer provided within the pack.

That is, master polyester A and normal polyester B are mixed appropriately in a static mixer 7, and then the P layer 8.
It is spun out from a nozzle brake (10) through a perforated plate (9).

The dilution in the second stage may be performed by a combination method in addition to the above-mentioned mixing method.

In this case, a conventionally known composite spinning pack may be used as the spinneret pack shown in FIG.

Composite forms include core-sheath type composite and sea-island type composite.

Any combination such as side-by-side type may be used.

Examples of static mixing devices used in the present invention include:
Static mixer manufactured by Keninox.

Commercially available static mixers such as Static Mixing Element manufactured by Sluzer and Himixer manufactured by Toshi ■ are preferably used.

The effects of the present invention will be specifically explained below with reference to Examples. In the examples, characteristic values were measured by the following method.

In addition, all "parts" mean parts by weight.

(Intrinsic viscosity of 11 modified polyester.2
The solution viscosity was measured at 0°C.

(2) The antistatic sample was washed for 2 hours in a weak alkaline aqueous solution of an anion activator of groups 0 and 2 using an electric washing machine, and then washed with water.

Length after drying (t) 5 m, fineness (D) 1000
Arrange them into denier fiber bundles and heat them at 20℃ and 40%RH.
After conditioning the humidity for a day, the resistance of the sample was measured using an electrometer at an applied voltage of 500 V, and the volume resistivity (Ω-m) calculated using a linear equation was used as a measure of antistatic property.

R: resistance (Ω-crn) D: fineness (denier) t: fiber sample length (crn) d: sample density (g/cr/l). ) Reference Example 1 A slurry of terephthalic acid and ethylene glycol (
The molar ratio of terephthalic acid/ethylene glycol is 1/1.
6) is continuously supplied.

React under the conditions of 250°C and 0.05 Ky/cJG,
When the residence time was 8 hours, the esterification reaction rate was 9.
Five BHETs were obtained continuously.

Reference Example 2 100 parts of BHET obtained in Reference Example 1 was transferred to a polymerization tank, and 2
It was heated to 80°C, and antimony trioxide was added as a catalyst to 2.0 mol of the total acid components constituting the polyester. OX1
0 mol to the reaction system and reacted for about 4 hours under high vacuum to complete polycondensation, [η) = 0BB (ttt/11
) polyethylene terephthalate was obtained.

13- Example 1 BHET2 made in Reference Example 1 in a polymerization can maintained at 250°C
After 75 parts of pulverized polyethylene glycol with a molecular weight of 2000 was added and melted, a solution of 0.06 parts of antimony trioxide dissolved in 3 parts of ethylene glycol as a polymerization catalyst was added, the temperature was raised to 270°C, and 1w
Polycondensation was performed at 270° C. for 5 hours under reduced pressure of +lHg or less to obtain a modified polyester with [η] = 0.96.

Next, this modified polyester was discharged from the polymerization can without being turned into chips, and mixed with the polyethylene terephthalate obtained in Reference Example 2, which was separately melted in the mixing system shown in Figure 1, at a ratio of 1=1, with a diameter of 1 inch and number of elements. were mixed and diluted using 10 K-EX static mixers.

The master polyester having a polyalkylene glycol content of 37.5% by weight obtained in this way was also used to change the polyalkylene glycol content of the final product by using the polyethylene terephthalate obtained in Reference Example 2 without turning it into chips. The mixture was diluted to 6% by weight (14%).

The spinning and drawing conditions were a spinning temperature of 80°C, a spinning speed of 1200 m10, and a nozzle plate having 36 pores with a diameter of 0.25 tm so that the denier composition of the final product (drawn yarn) was 75 denier/36 filaments. It was adjusted.

The static mixer installed inside the spinneret pack has a diameter of 7.
8wn with 9 elements was used.

The antistatic performance of the obtained fibers has a 1 volume resistivity of 8.6.
It was good at X10 (Ω-crn).

Example 2.3.4 and Comparative Example 1.2 In Example 1, the mixing ratio of the master polyester and modified polyester in the second stage was changed, and the content of polyalkylene glycol in the final product was reduced to 0.5% by weight. ′
t% (Comparative Example 1), 2.0, 4.0.

8.031i amount% (Example 2.3.4) and 12.
Example 1 except that it was changed to 0% by weight (Comparative Example 2)
Mixed spinning was carried out in the same manner as above. The results obtained are shown in Table 1.

Example 5.6 and Comparative Example 3.4 In Example 1, the blending ratio of BHET and polyethylene glycol was changed, and the blending ratio of polyalkylene glycol was 55% by weight (Comparative Example 3), 65% by weight, and 85% by weight.
6 (Example 5.6) and 95% by weight (Comparative Example 4) were synthesized by adjusting the polymerization time so that [η] was constant at 0.96, and the mixture shown in Figure 1 was also obtained. In both cases, the content of polyalkylene glycol in the master polyester is 40% by weight,
The content of polyalkylene glycol in the final product is 6.
Mixing and spinning was carried out in the same manner as in Example 1, except that the first and second stages were kneaded so that the result was 0% by weight.

These results are shown in Table 1. In the case of Comparative Example 4 in which the content of polyalkylene glycol in the modified polyester was extremely high, the miscibility with the normal polyester was too poor and the polyester phase and polyalkylene glycol phase were separated. Perhaps because the phase separation is too large, yarn breakage occurs frequently during final mixing and spinning, making it difficult to manufacture on an industrial basis.

Example 7 and Comparative Example 5.6 The mixing ratio of the modified polyester and normal polyester during the first stage of mixing and dilution in Example 1 was changed, and the polyalkylene glycol content was 25% by weight (Comparative Example 5).
), 55% by weight, 96% by weight (Example 7) and 70% by weight (Comparative Example 6) were obtained by mixing and spinning in the same manner as in Example 1, except that master polyesters were obtained. The results are shown in Table 1.

// 71. ' / 17- Table 1 [Note] ■FAG: Abbreviation for polyalkylene glycol 18- Example 8 In Example I, a core-sheath type composite spinning device was used instead of the mixed spinning bag, and the master polyester was used as the core. Next, polyethylene terephthalate was placed in the sheath and composite spinning was performed. In this case, the composite ratio of the nine components was selected so that the content of polyalkylene glycol to the entire composite fiber was 6.0% by weight. Other spinning conditions were the same as in Example 1, including spinning temperature and spinning speed, but the nozzle plate had a diameter of 0.4 mm.

A fiber with 24 holes was used, and the denier structure of the final product (drawn yarn) was adjusted to 75 denier/24 filaments.

The antistatic performance of the obtained composite fiber is 9, and the volume resistivity is 1.
．． It was good at 6X10 (Ω- side).

Comparative example 7 The first stage of mixing and dilution in Example 1 was omitted.

The mixing ratio of the modified polyester containing 75% by weight of polyalkylene glycol and polyethylene terephthalate was set to 11.5 IC, and the polyalkylene glycol content was diluted at once with a static mixer installed in the spinneret pack. was adjusted to have a weight ratio of 6, and mixed spinning was carried out. Because the mixing ratio of both is too large.

The mixed spots were unavoidably thick (and yarn breakage occurred frequently during spinning).Also, the volume resistivity of the obtained fiber was 2.5X.
However, the antistatic performance of iO(Ω-c1n)K was insufficient.

Example 9 Mixed spinning was carried out using the same method and conditions as in Example 1 except that the molecular weight of the polyalkylene glycol used in Example 1 was changed to 4000. The obtained fiber had a good volume resistivity of 1.6×10 (Ω-side). Note that [η] of the modified polyester at this time was 083.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a schematic diagram showing an example of a mixing system used in the present invention, and FIG. 2 shows an example of the spinneret pack of FIG. 1. In the figure, 1 is a polymerization can, 2 is a pipeline, 3 is a static mixer, 4 is a melt extruder, and 5 is a spinneret pack. 6 is a spun yarn, 7 is a static mixer, and 8 is a P layer. 9 is a perforated plate, and 10 is a nozzle plate. Patent applicant Yuzo Kodama, agent of Nippon Ester Co., Ltd. = 21- 1st

Claims (1)

[Claims] (1) A modified polyester obtained by adding more than 60% by weight and less than 90% by weight of polyalkylene glycol before the completion of polymerization of a polyester whose main repeating unit is ethylene terephthalate, and a normal polyester containing no polyalkylene glycol. Mix and dilute using a static mixer to obtain a master polyester with a polyalkylene glycol content of 30 to 60% by weight.Next, the master polyester and the normal polyester are mixed and diluted to have a polyalkylene glycol content of 30 to 60% by weight in the final product. 1.0
A method for producing an antistatic polyester fiber, which comprises mixing again in a static mixer or compounding to a concentration of ~10.0% by weight, and then spinning the fiber.