KR102113535B1 - Spun yarn comprising carbon fiber staple and method of manufacturing the same - Google Patents

Abstract

The spun yarn containing carbon fiber staples according to the present invention includes carbon fiber staples having a surface electrical resistivity of 10 ^-5 to 10 ¹⁰ Ωm and a modulus of 5 to 50 Gpa.
The spun yarn containing the carbon fiber staples is (i) flame-retarded to the precursor fiber for carbon fibers prepared by spinning a spinning solution containing a polyacrylonitrile-based polymer at 200 to 300 ° C., and then continues to 450 to 800. Carbonization treatment at a temperature of ℃ to prepare a carbon fiber having a surface electrical resistivity of 10 ^-5 to 10 ¹⁰ Ωm and a modulus of 5 to 50 Gpa, and then cutting the produced carbon fiber to a certain length to produce a carbon fiber staple; And (ii) a process for producing a spun yarn comprising the carbon fiber staples.
The spun yarn containing carbon fiber staples of the present invention has excellent antistatic properties and also includes carbon fiber staples having excellent flexibility, thereby improving antistatic performance, and also in the blending operation of carbon fiber staples and dissimilar fiber staples in the manufacture of the blend yarn. And spinning properties are greatly improved.

Description

Spun yarn comprising carbon fiber staple and method of manufacturing the same}

The present invention relates to a spun yarn comprising carbon fiber staples and a method of manufacturing the same, and more particularly, to a method of manufacturing the spun yarn having excellent antistatic performance with good blendability and spun workability.

Hereinafter, in the present invention, "spun yarn comprising carbon fiber staples" is used in the sense to include both yarns composed of only carbon fiber staples as well as blend yarns in which carbon fiber staples and heterogeneous fiber staples are blended.

As a prior art for producing carbon fiber staples used in the manufacture of a spinning yarn containing carbon fiber staples, precursor fibers for carbon fibers prepared by spinning a spinning solution containing a polyacrylonitrile-based polymer at 200 to 300 ° C. are 30 to 30 ° C. After the flameproofing for 200 minutes, the carbon fiber on the filament was prepared by continuously preliminarily carbonizing at 450-1,000 ° C for 1-3 minutes, and then continuously carbonizing at 1,150-1400 ° C for 1-3 minutes. , A method of manufacturing carbon fiber staples by cutting them to a certain length has been used.

The conventional carbon fiber staple manufactured as described above has excellent antistatic performance due to a low surface electrical resistivity of 10 ^-5 Ωm or less, but because it is carbonized at a high temperature of 1,000 ° C or higher, the flame resistant precursor fiber for carbon fiber is thermally decomposed. The composition ratio of the carbon component in the carbon fiber is increased to a level exceeding 98%. In particular, the covalent bonding between the carbon components is promoted, and the strength and modulus of the carbon fiber are rapidly increased to 100 to 1,000 Gpa.

As a result, the conventional carbon fiber staple manufactured as described above is susceptible to shear stress due to lack of flexibility due to high modulus, and thus a problem of easily breaking occurs.

In addition, in the case of producing a spun yarn by mixing a conventional carbon fiber staple and a heterogeneous fiber staple, there was a problem that the workability and spinning performance of the horns are greatly reduced.

An object of the present invention is to provide a method for manufacturing a spun yarn comprising carbon fiber staples having excellent antistatic performance with good spinning workability.

Another object of the present invention is to provide a method capable of greatly improving the workability of the mixed fibers when blending carbon fiber staples and heterogeneous fiber staples.

In order to achieve this problem, in the present invention, the surface electrical resistivity is 10 ^-5 ~ 10 ¹⁰ Ωm and the modulus is 5 ~ 50Gpa, using the carbon fiber staples alone to manufacture the spun yarn, or the carbon fiber staples 5 ~ 95 weight % And 95 to 5% by weight of heterogeneous fiber staples are mixed and spun to prepare a spun yarn comprising carbon fiber staples.

In addition, in the present invention, the precursor fiber for carbon fibers prepared by spinning a spinning solution containing a polyacrylonitrile-based polymer is flame-resistant at 200 to 300 ° C., and then carbonized at a temperature of 450 to 800 ° C. A carbon fiber having a surface electrical resistivity of 10 ^-5 to 10 ¹⁰ Ωm and a modulus of 5 to 50 Gpa is produced, and then the produced carbon fiber is cut to a certain length to produce a staple of carbon fiber, and then a spun yarn is produced using the same. .

The spun yarn containing the carbon fiber staple of the present invention includes an excellent antistatic property and a carbon fiber staple having excellent flexibility, so that the antistatic performance is improved and the spinning performance is improved.

In addition, when the carbon fiber staple and the heterogeneous fiber staple are mixed, the mixing workability is greatly improved.

Hereinafter, the present invention will be described in detail.

The manufacturing method of the spinning yarn containing the carbon fiber staples according to the present invention is (i) after the flame resistant treatment of the precursor fibers for carbon fibers prepared by spinning a spinning solution containing a polyacrylonitrile-based polymer at 200 to 300 ° C. , Carbonization is continuously performed at a temperature of 450 ~ 800 ℃ to produce carbon fibers with a surface electrical resistivity of 10 ^-5 to 10 ¹⁰ Ωm and a modulus of 5 to 50Gpa, and then the carbon fibers are cut by cutting the produced carbon fibers to a certain length. A process of manufacturing staples; And (ii) a process for producing a spun yarn comprising the carbon fiber staples.

Specifically, the present invention, first, the carbon fiber precursor fiber prepared by spinning a spinning solution containing a polyacrylonitrile-based polymer is flameproofed at 200 to 300 ° C, and then continuously carbonized at a temperature of 450 to 800 ° C. After processing, carbon fiber having a surface electrical resistivity of 10 ^-5 to 10 ¹⁰ Ωm and a modulus of 5 to 50 Gpa was prepared, and then the produced carbon fiber was cut to a certain length to prepare a carbon fiber staple.

When the carbonization temperature is less than 450 ° C, the surface electrical resistivity of the manufactured carbon fiber staples is 10 ¹⁰ Ωm or more, and the antistatic performance is insufficient, and when it exceeds 800 ° C, the surface electrical resistivity of the manufactured carbon fiber staples is 10 ² Ωm or less, the antistatic performance is excellent, but the covalent bonding of carbon components in the carbon fiber staple is promoted, so the modulus is more than 50 Gpa and lacks flexibility (too brittle). The knitting properties are also lowered.

In addition, when the carbonization temperature exceeds 800 ° C., the precursor fiber for carbon fiber is thermally decomposed to increase the content of the carbon component in the carbon fiber staple to exceed 98%.

The present invention suitably limits and adjusts the carbonization treatment temperature range so that the carbon fiber staples manufactured at the time of manufacturing the carbon fiber staples have both flexibility and antistatic performance.

The carbon fiber staples prepared by the above method have a surface electrical resistivity of 10 ^-5 to 10 ¹⁰ Ωm, a modulus of 5 to 50 Gpa, and more preferably, a composition ratio of carbon components in the carbon fiber staple is 75 to 98%.

The carbon fiber staple has excellent antistatic performance because the surface electrical resistivity is 10 ^-5 ~ 10 ¹⁰ Ωm, and at the same time, since the modulus is 5 ~ 50Gpa, it has high flexibility and low brittleness, and it is mixed with heterogeneous fiber staples in the manufacture of spun yarn. It improves and the spinning properties are also greatly improved.

Next, a spun yarn can be produced by using the carbon fiber staple alone, or mixed and spun from 5 to 95% by weight of the carbon fiber staple and 95 to 5% by weight of the heterogeneous fiber staple to produce a spun yarn in the form of a mixed yarn. .

When producing a spun yarn in the form of a blended yarn by mixing the carbon fiber staples and the heterogeneous fiber staples, if the content of the carbon fiber staples is less than 5% by weight, the antistatic performance may deteriorate, which is not preferable.

Aramid staples, polyester staples, nylon staples or mixtures thereof may be used as the heterogeneous fiber staples.

In particular, when the aramid staple is used as the heterogeneous fiber staple, light weight, heat resistance, and mechanical properties are greatly excellent, which is useful as a material for industrial protective equipment such as fire fighting clothing and safety gloves. At this time, the mixing ratio of the aramid staples is preferably 20 to 80% by weight, and if it is less than 20%, the protective performance decreases, and when it exceeds 80% by weight, the content of the carbon fiber staples decreases, so that the antistatic properties may decrease. .

The spun yarn comprising the carbon fiber staples of the present invention prepared as above is composed of 100% by weight of carbon fiber staples having a surface electrical resistivity of 10 ^-5 to 10 ¹⁰ Ωm and a modulus of 5 to 50 Gpa, or 5 to 95 of the carbon fiber staples It is composed of 95% by weight and 95% by weight of different fiber staples.

The spun yarn containing carbon fiber staples of the present invention has excellent antistatic properties and also includes carbon fiber staples having excellent flexibility, so that antistatic performance is improved and spinning properties are improved, especially carbon fiber staples and heterogeneous fiber staples are mixed. , When spinning, the mixability between the carbon fiber staples and the heterogeneous fiber staples is greatly improved.

Hereinafter, the present invention will be described in detail through examples and comparative examples.

However, the following examples are only examples of implementation of the present invention, and do not limit the protection scope of the present invention.

Example  One

A copolymer of 95 mol% of acrylonitrile, 3 mol% of methacrylic acid, and 2 mol% of itaconic acid was polymerized by a solution polymerization method using dimethyl sulfoxide as a solvent, and ammonia was added thereto in the same amount as itaconic acid. By neutralization, a polyacrylonitrile-based copolymer in the form of an ammonium salt was prepared to obtain a spinning dope having a content of the copolymer component of 22% by weight.

This spinning stock solution is discharged through a spinneret (temperature 45 ° C, 0.08mm in diameter, and two holes of 6,000 holes are used) and introduced into a coagulation bath which is an aqueous solution of 40% dimethyl sulfoxide controlled at 45 ° C. The test was made.

After washing the coagulated yarn, it was extended 5 times in hot water, and a network-modified silicone-based silicone emulsion was applied to obtain an intermediate stretched yarn.

The intermediate stretched yarn was dried using a heating roller, and then stretched in pressurized steam to obtain a bundle of polyacrylonitrile fibers having a total winding magnification of 10 times, a single fiber fineness of 1.5 dtex, and a filament number of 12,000. This is called a precursor fiber for carbon fiber.

The obtained polyacrylonitrile-based fiber bundle was subjected to preliminary flameproofing (with stretching) at 200 ° C for 6 minutes in an air atmosphere without substantially twisting at a rate of 4 m / min, and a temperature distribution of 220 to 270 ° C was obtained. Eggplants were flameproofed (with stretching) for 80 minutes in a four-stage hot air oven.

Next, carbon fiber was prepared by carbonizing the flame-retardant polyacrylonitrile-based fiber bundle at 450 ° C., and then cutting it to a length of 38 mm to prepare a carbon fiber staple.

Next, 80% by weight of the carbon fiber staples prepared as described above and 20% by weight of aramid staples were mixed and spun to prepare a carbon fiber staple / aramid staple blend yarn.

Table 2 shows the results of measuring the surface electrical resistivity, modulus, and crimp properties of the prepared carbon fiber staples and evaluating the mixed fiber workability of the carbon fiber staples and the aramid staples during the spinning process.

Example  2 ~ Example  10 and Comparative Example  1 ~ Comparative Example  7

Carbon fiber staples and carbon fiber staples in the same manner as in Example 1, except that the carbonization treatment temperature in the process of manufacturing the carbon fiber staples, the type of the heterogeneous fiber staples, and the mixing ratio of the carbon fiber staples and the heterogeneous fiber staples are changed as shown in Table 1. Carbon fiber staple / heterogeneous fiber staple blend yarn or carbon fiber staple sole spun yarn was prepared.

Table 2 shows the results of measuring the surface electrical resistivity, modulus and crimp properties of the prepared carbon fiber staples and evaluating the mixed fiber workability of the carbon fiber staples and the heterogeneous fiber staples during the spinning process.

division Carbonization temperature
(℃) Modulus
(Gpa) Types of different fiber staples Carbon fiber staple / heterogeneous fiber staple mixed weight ratio Example 1 450 9 Aramid staples 80/20 Example 2 550 11 Aramid staples 80/20 Example 3 650 13 Aramid staples 80/20 Example 4 750 25 Aramid staples 80/20 Example 5 650 13 Aramid staples 80/20 Example 6 650 13 Aramid staples 50/50 Example 7 650 13 Aramid staples 30/70 Example 8 650 13 Aramid staples 20/80 Example 9 450 9 Aramid staples 100/0 Example 10 650 13 Cotton staples 50/50 Comparative Example 1 300 5 Aramid staples 80/20 Comparative Example 2 400 8 Aramid staples 80/20 Comparative Example 3 1,200 190 Aramid staples 80/20 Comparative Example 4 1,300 220 Aramid staples 80/20 Comparative Example 5 650 13 Cotton staples 1/99 Comparative Example 6 300 5 Aramid staples 20/80 Comparative Example 7 1,200 190 Aramid staples 20/80

Spinning yarn properties and mixing workability division
Carbon fiber blend properties Surface electrical resistance
(Ωm) Crimp Honseom workability Example 1 1.0 × 10 ¹⁰ Great Great Example 2 2.5 × 10 ⁹ Great Great Example 3 3.6 × 10 ⁷ Great Great Example 4 2.2 × 10 ⁵ Great Great Example 5 3.6 × 10 ⁷ Great Great Example 6 1.1 × 10 ⁸ Great Great Example 7 5.1 × 10 ⁸ Great Great Example 8 6.5 × 10 ⁹ Great Great Example 9 1.0 × 10 ¹⁰ Great Great Example 10 1.0 × 10 ⁸ Great Great Comparative Example 1 5.0 × 10 ¹⁵ Good Good Comparative Example 2 4.1 × 10 ¹³ Good Good Comparative Example 3 ^- Bad Bad Comparative Example 4 - Bad Bad Comparative Example 5 4.0 × 10 ¹³ Good Good Comparative Example 6 5.2 × 10 ¹⁸ Good Good Comparative Example 7 ^- Bad Bad

The surface electrical resistivity was measured under conditions of 10V to 100V in Mitsubishi Chemical's Anellitech Corporation's Hiresta-UX (model MCP-HT800).

The modulus was measured by ASTM D 638 method using an Instron (universal testing machine).

Crimpability and mixed-omb workability were judged to be "excellent" when the staples were hardly broken or buried in powder form by the intuitive inspection, and mixed-blends were possible even when staples were partially broken or powdered. Was judged as "good", and the case where the spinning was impossible because the staples were broken, buried in powder form, or clumped during honsum operation was judged as "bad".

Claims (8)

A spun yarn comprising carbon fiber staples, characterized in that it comprises carbon fiber staples having a surface electrical resistivity of 10 ^-5 to 10 ¹⁰ Ωm and a modulus of 5 to 25 Gpa. The carbon fiber staple according to claim 1, wherein the spun yarn comprising the carbon fiber staples is composed of 100% by weight of carbon fiber staples having a surface electrical resistivity of 10 ^-5 to 10 ¹⁰ Ωm and a modulus of 5 to 25 Gpa. Including spun yarn. The method of claim 1, wherein the spun yarn containing the carbon fiber staples has a surface electrical resistivity of 10 ^-5 ~ 10 ¹⁰ Ωm and a modulus of 5 ~ 25Gpa carbon fiber staples 5 ~ 95% by weight and heterogeneous fiber staples 95 ~ 5% by weight A spun yarn comprising carbon fiber staples, characterized in that is blended. The spun yarn of claim 1, wherein the content of the carbon component in the carbon fiber staple is 75 to 98%. (Ⅰ) The carbon fiber precursor fiber prepared by spinning a spinning solution containing a polyacrylonitrile-based polymer is flameproofed at 200 to 300 ° C., and then carbonized at a temperature of 450 to 750 ° C. A process of manufacturing carbon fibers having a specific resistance of 10 ^-5 to 10 ¹⁰ Ωm and a modulus of 5 to 25 Gpa, and then cutting the produced carbon fibers to a certain length to produce carbon fiber staples; And
(Ii) a process for producing a spun yarn comprising the carbon fiber staples; a method for producing a spun yarn comprising carbon fiber staples. The method of claim 5, wherein the surface electrical resistivity is 10 ^-5 to 10 ¹⁰ Ωm, and the modulus is 5 to 25 Gpa. The method of claim 5, wherein the surface electrical resistivity is 10 ^-5 ~ 10 ¹⁰ Ωm and 5 ~ 95% by weight of carbon fiber staples having a modulus of 5 ~ 25Gpa and 95 ~ 5% of heterogeneous fiber staples are mixed to produce a spun yarn. Method for producing a spun yarn comprising a carbon fiber staple. The method of claim 7, wherein the heterogeneous fiber staple is one or two or more selected from aramid staples, polyester staples, and nylon staples.