KR101564470B1 - Method for Preparing Polybuthylene terephthalate fiber and Polybuthylene terephthalate fiber prepared by the same - Google Patents

Abstract

The present invention relates to a method for producing polybutylene terephthalate fibers by preparing polybutylene terephthalate polymer by spinning to prepare an unstretched fiber and stretching the unstretched fiber to optimize the physical properties and stretching conditions of the unstretched fiber, To a process for producing polybutylene terephthalate fibers, and to polybutylene terephthalate fibers produced thereby.

Polybutylene terephthalate, fiber, stretch, undrawn yarn, dyeability, high strength

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polybutylene terephthalate fiber and a polybutylene terephthalate fiber prepared by the same,

The present invention relates to a process for producing a polybutylene terephthalate fiber and a polybutylene terephthalate fiber produced thereby, and more particularly to a process for producing a polybutylene terephthalate fiber, which comprises polybutylene terephthalate fiber which improves dyeability and mechanical properties by adjusting physical properties and stretching conditions of non- And a polybutylene terephthalate fiber produced by the method.

Polybutylene terephthalate (hereinafter referred to as "PBT") is a polymer material produced by esterification of terephthalic acid and 1,4-buthandiol, or polycondensation after transesterification of dimethyl terephthalate and butanediol, It is one of the most excellent polymer materials in comparison with polyamide, polyacetyl, polycarbonate, modified polyphenylene oxide, etc. in balance of heat resistance, formability, weather resistance and chemical resistance.

Polybutylene terephthalate is synthesized and sold for use in non-reinforcing, reinforcing, flame-retarding and high-polymer alloys. The crystallization rate of polybutylene terephthalate is about 10 times faster than that of polyethylene terephthalate (PET) Chemically, it has an ester bond, which is structurally well hydrolyzed. When it is fibrous, it exhibits an intermediate mechanical property between nylon and PET.

The polybutylene terephthalate fiber has an elasticity almost twice as high as that of the polyester fiber, has a soft touch feeling, and has an advantage of low temperature dyeing (100 ° C). Also, it has excellent chlorine resistance, light resistance and chemical resistance, and it is widely used for sports wear such as swimwear, women's clothing, socks and jeans.

However, polybutylene terephthalate fibers generally exhibit a strength of less than 4 grams per denier, which is lower than polyester fibers exhibiting a physical property of at least 4.5 grams / denier, and polybutylene terephthalate fibers have such low strength There is a limitation of use.

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a method for producing polybutylene terephthalate fibers having improved physical properties such as dyeability and strength by optimizing physical properties and stretching conditions of non- .

Another object of the present invention is to provide a polybutylene terephthalate fiber having excellent mechanical properties such as dyeability and strength.

One aspect of the present invention to attain the above object is to provide a polybutylene terephthalate polymer which is spinnable at a spinning speed of 1,200 to 1,800 m / min to obtain a final monofilament fineness of 0.8 to 3 denier, an elongation of 200 to 230% A step of sacrificing an undrawn gin which is 1.8 to 2.3 grams / denier; And then the stretching ratio between the feed roller and the hot roller is 2.3 to 3.0, the overdrive ratio of the cold roller to the take-up speed is 7 to 10%, the hot roller temperature is 130 to 150 캜, and the hot plate temperature is 200 to 230 캜 And a step of stretching the polybutylene terephthalate fiber under the condition that the polybutylene terephthalate fiber has excellent durability and physical properties.

Another aspect of the present invention relates to a polybutylene terephthalate fiber produced by the method of the present invention and having a single fiber fineness of 0.8 to 3.0 denier, an intensity of 6.5 to 8.0 g / denier, an elongation of 15% or less and a shrinkage ratio of 10%

According to the present invention, in the production of a polybutylene terephthalate fiber by preparing a non-drawn filament yarn by spinning the polybutylene terephthalate polymer and then spinning the non-drawn filament yarn, the physical properties and stretching conditions of the non- High strength polybutylene terephthalate fibers having a strength of 6.5 grams / denier or more can be produced.

Hereinafter, the present invention will be described in more detail.

According to one aspect of the present invention, the polybutylene terephthalate polymer is spun at a spinning speed of 1,200 to 1,800 m / min to obtain a final monofilament fineness of 0.8 to 3 denier, elongation of 200 to 230%, strength of 1.8 to 2.3 g / After the denier non-drawn yarn is removed, the stretching ratio between the feed roller and the hot roller is set to 2.3 to 3.0, the overdrive ratio between the cold roller and the winding speed is set to 7 to 10%, the hot roller temperature is set to 130 to 150 ° C, And then stretched under the process conditions of a temperature of 200 ° C to 230 ° C to produce a polybutylene terephthalate fiber.

1 is a schematic view of a process for producing a polybutylene terephthalate fiber according to an embodiment of the present invention. Referring to Figure 1, each step of the method of the present invention will be described in detail.

The method of the present invention is to produce a high-strength polybutylene terephthalate fiber having an excellent dyability and physical properties by optimizing the physical properties and stretching conditions of the unstretched fiber. The polybutylene terephthalate polymer is spin- Manufacture of undrawn gin.

In other words. A step of extruding the polybutylene terephthalate polymer, a step of extruding the polybutylene terephthalate polymer, a step of extruding the polybutylene terephthalate polymer, and a step of drawing the discharged polymer at a spinning speed of 1,200 to 1,800 m / min to adjust the final monofilament fineness to 0.8-3 denier 200 ~ 230%, strength 1.8 ~ 2.3 grams / denier.

The melting of the polymer is generally performed by using an extruder or a pressure melter. The molten polymer is then metered in a known manner and extruded from the spinneret. At this time, it is preferable to keep the spinning temperature within a range of from 245 DEG C to 270 DEG C to prevent complete melting of the polymer and decrease in viscosity. The polymer discharged from the spinneret is then cooled and solidified into fibers.

In the present invention, the polybutylene terephthalate polymer is made to have a low spinning speed of 1,200 to 1,800 m / min, and thereafter the final monofilament fineness is 0.8 to 3.0, elongation is 200 to 230%, strength is 1.8 to 2.3 g / (Not shown). Next, the obtained undrawn yarn 100 is fed to a feeding roller 10, a hot roller 20, a hot plate 30, a cold roller 40 and a take-up machine 50 The stretching ratio between the feed roller 10 and the hot roller 20 is 2.3 to 3.0, the temperature of the hot roller 20 is 130 to 150 占 폚, the temperature of the hot plate 30 is 200 to 230 占 폚, The roller 40 and the overfeed at a winding speed of 7% to 10% To produce a high strength polybutylene terephthalate fiber (200). The yarn produced within the above-described process conditions exhibits high strength and low shrinkage characteristics, has little drop in strength due to heat, has excellent heat resistance, and has improved dyeability.

If the elongation and strength of the non-drawn yarn are out of the above range, the yarn becomes poor in durability and appearance, and practicality deteriorates.

When the spinning speed is less than 1,200 m / min, the spinning is difficult because of low spinning tension, and the productivity is low and it is difficult to apply. On the other hand, when the spinning speed exceeds 1,800 m / min, There arises a problem that the quality of the yarn is lowered.

When the stretching ratio between the feed roller 10 and the hot roller 20 is less than 2.3 times, it is difficult to exhibit the required high strength characteristics. When the stretching ratio exceeds 3.0 times, the quality of the yarn is deteriorated due to generation of crow. If the overfeed of the cold roller 40 and the winding speed is less than 7%, the contraction ratio exceeds 10%, and when the overfeed exceeds 10%, the warpage becomes severe and the workability is lowered.

When the heat treatment temperature in the hot roller 20 is less than 130 캜, the dyeing property and appearance are poor due to non-uniform stretching. When the heat treatment temperature is more than 150 캜, the flaking on the hot roller 20 becomes severe.

When the heat treatment temperature in the hot plate 30 is less than 200 ° C, the dyeing property and appearance are poor due to non-uniform stretching. When the temperature is higher than 230 ° C, the cut and frequent occurrence of tar on the hot plate 30 occur, do.

The polybutylene terephthalate fiber produced by the method of the present invention has a final drawn yarn single yarn fineness of 0.8 to 3.0 denier, a strength of 6.5 to 8.0 g / denier, an elongation of 15% or less, and a shrinkage ratio of 10% or less. The polybutylene terephthalate fiber of the present invention has excellent strength and dyeability, and has a low shrinkage ratio, so that the polybutylene terephthalate fiber of the present invention can be applied to applications requiring high strength such as embroidery yarn and lightweight parchment fabric.

Hereinafter, the present invention will be described more specifically by way of examples, but they should not be construed as limiting the scope of protection of the present invention.

Example

In this example, the physical properties of the polybutylene terephthalate fiber were evaluated by the following methods.

≪ Method for measuring physical properties &

1) Strength and elongation : measured with an universal measuring instrument (Instron).

2) Method of measurement of shrinkage : It is expressed as a rate of change in length before and after heat treatment for 15 minutes in a drying oven at 190 ° C.

Shrinkage (%) = (L ₀ -L ₁ ) / L ₀ 100

(L ₀ : length before heat shrinkage, L ₁ : length after heat shrinkage)

3) Dyeability

- Dyeing: use of Mathis mangle [Dye used: Microsolorange GR 0.3 wt% solution (manufactured by Ciba-Geigy)],

- Thermoset: use of Mathis steamer,

- Colorimetry: Using Computer Color Matching (CCM)

- Dyeability evaluation: Comparison of K / S value of dye.

4) Appearance

The fiber appearance was evaluated as good (∘) when 30 or more were judged as good (∘), good (△) when 20 or more were judged as good (X) was judged to be the case where a dyeing line such as a dyed yarn occurred.

Example  One

A polybutylene terephthalate polymer having an intrinsic viscosity of 0.84 was spin-coated at a spinning temperature of 260 ° C, a hole diameter of 0.23 mm and a hole length of 0.46 mm to prepare an undrawn yarn by controlling the discharge amount and spinning speed so that the final single yarn fineness became 0.8 denier Respectively. The obtained non-drawn filament was stretched at a stretching speed of 750 m / min, a stretching ratio of 2.5, a hot roller of 130 占 폚, a hot plate temperature of 220 占 폚, and a cold roller and an overfeed of 7% at a winding speed to produce a polybutylene terephthalate filament yarn.

The physical properties, elongation conditions, and elongation properties of the unstretched gauges were measured, and the results are shown in Table 1 below.

Example  2

The polybutylene terephthalate filament yarn was produced in the same manner as in Example 1 except that the final monofin fineness of the drawn yarn was 2.9 denier and the stretching ratio was 2.8. The properties were evaluated in the same manner as in Example 1, Respectively.

Comparative Example  One

A polybutylene terephthalate filament yarn was produced in the same manner as in Example 1 except that the final single yarn fineness of the drawn yarn was 0.5 denier and the stretching ratio was 2.3. The properties were evaluated in the same manner as in Example 1, Respectively.

Comparative Example  2

The polybutylene terephthalate filament yarn was produced in the same manner as in Example 1 except that the final single yarn fineness of the drawn yarn was changed to 4 denier and the stretching ratio was 2.9. The properties were evaluated in the same manner as in Example 1, Respectively.

Comparative Example  3

The same procedure as in Example 1 was repeated except that a hot roller at 100 ° C and a hot plate temperature of 180 ° C were used to prepare polybutylene terephthalate filament yarn, and the properties were evaluated in the same manner. The results are shown in Table 1 .

Comparative Example  4

A polybutylene terephthalate filament yarn was produced in the same manner as in Example 1, except that the physical properties of the unstretched yarn were adjusted so as to adjust the spinning speed so that the elongation was 180%, the strength was 2.4 g / denier, and the stretching ratio was 2.3 The properties were evaluated in the same manner and the results are shown in Table 1 below.

division Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 The last opened yarn
(Den / Fila) 0.8 2.9 0.5 4.0 0.8 0.8 Unfinished shrine property Shinto (%) 210 230 205 205 210 180 Strength (g / d) 2.2 1.8 1.8 1.9 2.2 2.4 Stretching
Condition Hot Roller Temperature (℃) 130 130 130 130 100 130 Hot plate temperature (캜) 220 220 220 220 180 220 Stretching cost 2.5 2.8 2.3 2.9 2.5 2.3 Overfeed
(%) 7.0 7.0 7.0 7.0 7.0 7.0 A kite
Properties Strength (g / d) 6.6 7.5 5.5 7.3 6.2 6.9 Shinto (%) 15 13 14 14 13 14 Shrinkage (%) 9.5 9.2 10.8 9.9 12.0 12.3 Exterior ○ ○ X △ X X Dyeability ○ ○ △ X X X

As can be seen from the above Table 1, the polybutylene terephthalate fiber produced by the method of the present invention exhibits excellent heat resistance and durability by lowering strength by heat.

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.

1 is a schematic view of a process for producing a polybutylene terephthalate fiber according to an embodiment of the present invention.

Description of the Related Art [0002]

10: feed roller 20: hot roller

30: hot plate 40: cold roller

50: Winding machine 100: Unstable gentleman

200: Polybutylene terephthalate fiber (drawn yarn)

Claims (2)

Spinning the polybutylene terephthalate polymer at a spinning speed of 1,200 to 1,800 m / min to produce an undrawn yarn having a final single yarn fineness of 0.8 to 3 denier, elongation of 200 to 230%, and strength of 1.8 to 2.3 g / denier; And then the stretching ratio between the feed roller and the hot roller is 2.3 to 3.0, the overdrive ratio of the cold roller to the take-up speed is 7 to 10%, the hot roller temperature is 130 to 150 캜, and the hot plate temperature is 200 to 230 캜 Wherein the polybutylene terephthalate fiber is a polybutylene terephthalate fiber having an excellent dyability and physical properties. The polybutylene terephthalate polymer was spun at a spinning speed of 1,200 to 1,800 m / min to prepare a non-drawn filament having a final monofilament fineness of 0.8 to 3 denier, elongation of 200 to 230% and strength of 1.8 to 2.3 g / The stretching ratio between the feed roller and the hot roller is in the range of 2.3 to 3.0, the overfeed of the cold roller and the take-up speed is 7 to 10%, the hot roller temperature is 130 to 150, and the hot plate temperature is 200 to 230 , Polybutylene terephthalate fibers having a final drawn yarn single yarn fineness of 0.8 to 3.0 denier, a strength of 6.5 to 8.0 g / denier, an elongation of 15% or less and a shrinkage ratio of 10% or less.

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