KR101429686B1 - Process for preparing high viscosity and high intensity industrial polyester fibre - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the production of high viscosity, high strength industrial polyester (PET) fibers, and is capable of producing chain extension reaction of CBC, p-BOX and m- The present invention relates to a method for producing an industrial PET yarn having an increased intrinsic viscosity and excellent viscosity and toughness compared to conventional high strength PET fibers.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a high-

More particularly, the present invention relates to a method for improving the intrinsic viscosity of PET by introducing a chain extender in a process of melt-spinning a conventional PET chip, It is about.

A conventional method useful for increasing the strength of PET fibers used for industrial purposes is to melt a highly viscous chip having an intrinsic viscosity of 1.0 or higher and then melt the polymer by raising the temperature of the molten polymer sufficiently to 300 DEG C and solidify the same. And then unwinding the unstretched web obtained by direct stretching at a draw ratio of 5.0 or more in the first and second stages, followed by relaxation and winding. At this time, low-speed winding lowers the degree of orientation of undrawn yarns and gives high-strength stretching to obtain high strength characteristics. The conventional method as described above is characterized in that the temperature of the heating hood and the cooling wind is appropriately adjusted to minimize the degree of orientation of the non-drawn filament, and then the filament is drawn at a high magnification. When the stretching magnification is increased to obtain fibers having higher strength by using the conventional spinning technique, the viscosity at the time of spinning, the increase in the shrinkage ratio of the yarn due to high-rate stretching, and the shape stability are lowered due to the high temperature of the heating hood during spinning. A large number of finishing threads and finishing problems occur due to a large number of spinning yarns caused by high-ratio stretching, resulting in poor post-processability. In addition, there is a problem in that the viscosity of the high-viscosity PET resin is lowered during spinning, and the shrinkage ratio of the yarn due to high-degree stretching is increased and the shape stability is lowered.

In order to overcome the above problem, the high modulus low shrinkage (HMLS) method also shows that when the strength is taken into consideration in terms of strength and shape stability (shrinkage ratio + Chinese shine), the shape stability is lowered. There is a problem that can not be done.

Korean Patent Publication No. 10-1999-0002210 (January 15, 1999)

It is an object of the present invention to provide a method for producing a high strength PET fiber which does not use a solid phase polymerization method and can significantly improve intrinsic viscosity of PET or a copolymer thereof.

In the present invention, chain extender such as CBC, p-BOX and m-BOX added with a small amount in the production of high strength yarn for the PET industry reacts with alcohol and carboxylic acid at the terminal of the PET chain to cause chain extension reaction to increase intrinsic viscosity, High-strength yarns for the PET industry.

The present invention relates to a process for producing polyester fibers for high viscosity and high strength by melting polyethylene terephthalate followed by spinning and winding to obtain a polyester fiber having an intrinsic viscosity of 0.8 to 1.10 and carbonyl bis caprolactam CBC), 1,4-phenylene bis oxazoline (p-BOX), and 1,3-phenylene bis oxazoline (m-BOX) , In an amount of 0.25 to 1.00 wt% in a melt spinning process. The present invention also provides a process for producing a high-viscosity high-strength industrial polyester fiber.

According to a preferred embodiment of the present invention, the polyester fiber has a strength of 8.0 to 13.0 g / d, wherein the intrinsic viscosity of the polyester fiber is 0.07 to 0.14 relative to the viscosity of the polyethylene terephthalate chip .

According to another preferred embodiment of the present invention, the polyester fiber has an intrinsic viscosity of 1.0 to 1.1.

According to the present invention, it is possible to produce industrial PET fibers having superior viscosity and toughness compared to existing high-strength yarns and to produce geotextile for disaster prevention by increasing viscosity of PET yarn and increasing strength due to increase in elongation, And the like.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a process for extending a chain of PET by a chain extender.
Figure 2 shows the molecular weight increase effect according to the content of the chain extender.

The present invention is described in detail as follows.

The present invention relates to a process for producing polyester fiber for high viscosity and high strength by melting polyethylene terephthalate followed by spinning and winding to obtain carbonyl bis caprolactam (CBC) in a polyester chip having an intrinsic viscosity of 0.8 to 1.10, , 1,4-phenylene bis oxazoline (p-BOX), and 1,3-phenylene bis oxazoline (m-BOX). Characterized in that one kind of compound is added in an amount of 0.25 to 0.75% by weight in a melt spinning process.

0.25 to 1.00 wt% of CBC, p-BOX and m-BOX were added in the composition of the present invention, and the intrinsic viscosity of the fiber after spinning (described in Fila IV in Table 1-3) was 1.0 to 1.1 , And the viscosity of the polyethylene terephthalate chip as the raw material was increased by 0.07 to 0.14. Further, the polyester fiber produced by the present invention has a strength of 8.0 to 13.0 g / d.

If the content of the chain extender is less than 0.25% by weight, the effect of improving the viscosity is insignificant, and if the content of the chain extender is more than 0.75% by weight, the intrinsic viscosity is rather reduced. This can be a criterion for judging that the PET chain decomposition reaction due to the pyrolyzed additive is more dominant than the chain extender participating in the reaction at the melting temperature.

If the intrinsic viscosity of the polyester fiber is less than 1.0, the effect of improving the strength of the yarn due to the production of the high viscosity fiber is insignificant. If the intrinsic viscosity exceeds 1.1, the extruder inner pressure is increased And the nozzle may be closed to cause a problem in the process, and it becomes one of the causes of failing to obtain high-quality fibers due to the segments of the produced yarn.

The intrinsic viscosity (IV) of the PET prepared according to the present invention was measured by measuring the relative viscosity of a solution prepared by dissolving 80 g of a sample in 100 ml of orthochlorophenol using a Ubbel road viscometer at 25 and calculating IV by the following approximate equation .

only,

t: Drop time of solution (sec)

t ₀ : Falling time of orthochlorophenol (sec)

d: density of solution (g / cc)

d ₀ : density of orthochlorophenol (g / cc)

Hereinafter, the present invention will be described in more detail with reference to Examples, but these Examples do not limit the scope of protection of the present invention.

≪ Method for measuring physical properties &

1. How to measure the strength of yarn

The yarn is allowed to stand in a standard condition, that is, in a constant temperature and humidity room at 25 ° C and a relative humidity of 65% for 24 hours, and then the sample is measured by a tensile tester using the ASTM 2256 method.

Comparative Example 1

A conventional PET chip was spin-drawn using a spinneret having a spinning temperature of 298 DEG C, a hole diameter of 0.63 mm, and a hole length of 1.89 mm to adjust the discharge amount to 126 filaments and final monofilament fineness to 7.9 denier At a spinning speed of 2623 m / min. An interlace nozzle was installed on the upper part of the winder by fixing the draw ratio between the first and fourth stages of the Godet Roller to 5.8 and the guide was a pipe guide having a length of 20 mm and a diameter of 2 mm, In the process of producing a polyester filament yarn with entanglement with compressed air of 3.5 kgf / cm 2 by applying the mold, a test was conducted under the condition that no chain extender was added to PET having an IV of 1.05, and the fila IV And denier, strength, strength, elongation and toughness are shown in Table 1.

Examples 1-4

Fiber was prepared under the same conditions as in Comparative Example 1 except that CBC was directly or master-batch-polymerized to PET having an IV of 1.05 and added in an amount of 0.25 to 1.00 wt%. Fila IV and denier, strength, strength, elongation and toughness of the produced fiber are shown in Table 1.

Comparative Example 1 Example 1 Example 2 Example 3 Example 4 Chain Extender Type - CBC CBC CBC CBC Chain extender content (wt%) 0.00 0.25 0.50 0.75 1.00 Fila IV (dl / g) 0.95 1.04 1.07 1.09 1.07 Denier 1011 1012 1009 1012 1015 Strong (g / d) 10.51 10.54 10.38 10.55 10.27 Strength (g / d) 10.40 10.42 10.29 10.42 10.12 Elongation (%) 12.20 14.89 15.22 15.60 13.10 Toughness 36.31 40.19 40.13 41.18 36.62

Comparative Example 2

IV of 1.05 was tested under the same conditions as in Comparative Example 1 except that no chain extender was added. Fila IV and denier, strength, strength, elongation and toughness of the produced fibers were shown in Table 2 .

Examples 5-8

IV was 1.05, the p-BOX was directly or master-batched and added in an amount of 0.25 to 1.00 wt%, and the same conditions as those of Comparative Example 1 were tested. Fila IV and denier, strength, And toughness results are shown in Table 2. < tb >< TABLE >

Comparative Example 2 Example 5 Example 6 Example 7 Example 8 Chain Extender Type - p-BOX p-BOX p-BOX p-BOX Chain extender content (wt%) 0.00 0.25 0.50 0.75 1.00 Fila IV (dl / g) 0.92 0.94 0.99 0.95 0.89 Denier 1005 1022 1015 1013 1010 Strong (g / d) 10.41 10.32 10.59 10.21 10.24 Strength (g / d) 10.36 10.10 10.43 10.08 10.14 Elongation (%) 12.72 13.52 13.87 12.28 11.20 Toughness 36.94 37.13 38.86 35.32 33.93

Comparative Example 3

IV of 1.05 was tested under the same conditions as in Comparative Example 1, except that no chain extender was added. Fila IV and denier, strength, strength, elongation and toughness of the produced fibers were shown in Table 3 .

Examples 9-12

IV was 1.05, m-BOX was directly or master-batched and added in an amount of 0.25 to 1.00 wt%, and the same conditions as in Comparative Example 1 were tested. Fila IV and denier, strength, And toughness results are shown in Table 3.

Comparative Example 3 Example 9 Example 10 Example 11 Example 12 Chain Extender Type - m-BOX m-BOX m-BOX m-BOX Chain extender content (wt%) 0.00 0.25 0.50 0.75 1.00 Fila IV (dl / g) 0.90 0.96 1.01 1.06 1.05 Denier 1021 1018 1022 1009 1016 Strong (g / d) 10.58 10.55 10.68 10.65 10.47 Strength (g / d) 10.36 10.36 10.45 10.56 10.31 Elongation (%) 12.11 13.82 14.01 14.30 13.51 Toughness 36.06 38.53 39.11 39.91 37.88

Claims (4)

Polyethylene terephthalate is melted and then spun and wound to produce polyester fibers for high viscosity and high strength industries,
(CBC) and 1,4-phenylene bis oxazoline (p-BOX) were added to a polyester chip having an intrinsic viscosity of 0.8 to 1.10 dl / g, ) And 1,3-phenylene bis oxazoline (m-BOX) in the melt spinning process in an amount of 0.25 to 1.00 wt% based on the total weight of the spinning resin, By weight based on the total weight of the high-strength and high-strength industrial polyester fibers.
The method according to claim 1,
Wherein the polyester fiber has a strength of 8.0 to 13.0 g / d.
The method according to claim 1,
Wherein the intrinsic viscosity of the polyester fiber is increased by an absolute value difference of 0.07 to 0.14 dl / g with respect to the viscosity of the polyethylene terephthalate chip.
The method according to claim 1,
Wherein the polyester fiber has an intrinsic viscosity of 1.0 to 1.1 dl / g.

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