KR102201043B1 - Method and apparatus of producing carbon fiber using drying-spinning process - Google Patents

Abstract

The present invention relates to a carbon fiber manufacturing method using dry spinning and a manufacturing apparatus of carbon fibers manufactured by the manufacturing method. More particularly, the present invention relates to a carbon fiber manufacturing method using dry spinning and a manufacturing apparatus of carbon fibers manufactured by the manufacturing method, wherein an optimal carbon nanotube forest for manufacturing carbon fibers is produced, and productivity of carbon fibers can be improved by having excellent yields due to the carbon nanotube forest. Also, the carbon fibers can have transparent conductivity by being applied to various fields such as electrodes, heaters, solar cells and the like.

Description

A carbon fiber manufacturing method using dry spinning, and a carbon fiber manufacturing apparatus manufactured by the manufacturing method {METHOD AND APPARATUS OF PRODUCING CARBON FIBER USING DRYING-SPINNING PROCESS}

The present invention relates to a carbon fiber manufacturing method using dry spinning and a carbon fiber manufacturing apparatus manufactured by the above manufacturing method, and more specifically, to prepare an optimal carbon nanotube forest for manufacturing carbon fibers. , Due to the carbon nanotube forest, the carbon fiber production method using dry spinning can be applied to various fields such as electrodes, heaters, solar cells, etc., and the method of manufacturing carbon fiber using dry spinning, which has excellent yield and can improve the productivity of carbon fiber. It relates to a carbon fiber manufacturing apparatus manufactured by a manufacturing method.

Carbon Nanotube (CNT) has excellent mechanical properties, low electrical resistivity, and high thermal conductivity. For example, carbon nanotubes have a lower density than aluminum and have a tensile strength of about 370 times stronger than that of iron, and their electrical resistivity and thermal conductivity are similar to those of copper and diamond, respectively. Applicability is suggested in a wide range of fields such as aviation, sports, and defense. For example, a carbon nanotube having a tensile strength of 35 GPa and a tensile modulus of 1 Tpa has been reported.

Carbon Nanotube Fiber (CNTF) is an aggregate of carbon nanotubes formed to have a macro size so that carbon nanotubes can be easily applied to various fields. Since carbon nanotube fibers are manufactured by agglomerating carbon nanotubes having excellent physical properties, the possibility of application as a fiber material that surpasses commercially available high-performance fiber materials such as aramid fiber and carbon fiber has been noted.

In the conventional general method of manufacturing high-purity carbon nanotube fibers, a solution in which carbon nanotubes are dispersed is directly spun into a rotating container containing a polymer solution, so that the polymer solution penetrates between the carbon nanotube particles to penetrate the carbon nanotubes. It is generally known to bond to make fibers.

However, when the solution is directly spun as described above, the diffusion rate of the polymer solution through the carbon nanotubes is slow, and the manufacturing efficiency of the carbon nanotube fibers is limited due to the limitation of the speed at which the container containing the polymer solution is rotated. There is a problem. In addition, since about 30 wt% of the produced carbon nanotube fibers are polymers, the excellent characteristics of carbon nanotubes are limited.

In addition, the excellent physical properties of carbon nanotubes are limited only to individual carbon nanotubes, and with the current technology, only carbon nanotube fibers that are far less than the properties of existing carbon nanotubes can be manufactured. It is not easy to produce carbon nanotube fibers that represent.

Therefore, in order to compensate for the above-described problems, the present inventors recognized that the development of a method and apparatus for manufacturing carbon fibers using dry spinning is urgent, and thus completed the present invention.

Korean Registered Patent Publication No. 10-1766143 Korean Patent Publication No. 10-1972987

It is an object of the present invention to produce an optimal carbon nanotube forest for producing carbon fibers, and thereby a carbon fiber manufacturing method and manufacturing apparatus using dry spinning capable of manufacturing carbon fibers with excellent yield Is to provide.

Another object of the present invention is that a strong Van der Waals' force exists between each of the carbon nanotubes forming a carbon nanotube layer, thereby having a high density, and thus excellent strength It is to provide a carbon fiber manufacturing method and manufacturing apparatus using dry spinning capable of manufacturing the carbon fiber having a.

The problems of the present invention are not limited to the problems mentioned above, and other problems that are not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, the present invention provides a carbon fiber manufacturing method and manufacturing apparatus using dry spinning.

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

The present invention provides a method for producing carbon fibers using dry spinning comprising the following steps.

(S1) preparing a carbon nanotube forest composed of carbon nanotubes;

(S2) fixing one surface of the carbon nanotube forest to a carbon fiber supply unit and fixing the other surface to a collecting unit;

(S3) forming a film-shaped carbon nanotube layer by spinning the collecting portion at a rate of 1 to 10 mm per second; And

(S4) manufacturing a carbon fiber by rotating the collecting part 360 ° to twist the surface of the carbon nanotube.

In the present invention, the (S5) step of imparting tension to the carbon fiber produced in the (S4) step; characterized in that it further comprises.

In the present invention, the carbon nanotube forest is characterized in that it comprises the following steps.

(S1A) depositing alumina (aluminum oxide, Al ₂ O ₃ ) on one surface of a silicon (SiO ₂ ) substrate to a thickness of 1 to 5 nm;

(S1B) depositing an iron (Fe) catalyst to a thickness of 2 to 3 nm on one surface of the alumina; And

(S1C) preparing a carbon nanotube forest by using a chemical vapor deposition (CVD) method of carbon nanotubes on one surface of the iron catalyst.

In the present invention, an alloy of 1 to 3 nm is formed between the alumina and the iron catalyst.

In the present invention, in the step (S3), the carbon nanotube surface is characterized in that it is formed of 100 to 500 mm.

In the present invention, the surface of the carbon nanotubes prepared in step (S3) is characterized in that it is formed by the action of attractive force due to a Van der Waals' force existing between the carbon nanotubes. .

In the present invention, in the step (S4), the collecting unit is rotated 360 ° once per second.

In addition, the present invention provides a carbon fiber manufacturing apparatus, characterized in that for manufacturing the carbon fiber manufactured by the above method.

In the present invention, the carbon fiber manufacturing apparatus includes a body portion; A supply unit located on one side of the body unit and configured to supply a carbon nanotube forest; A collecting unit for forming a surface of carbon nanotubes by spinning the carbon nanotube forest fixed to the supply unit and producing a tamso fiber; A moving part for moving the collecting part at a constant speed; And a tension part for imparting tension to the carbon fiber manufactured by the collecting part.

In the present invention, the collecting part is a fixing rod to which the other surface of the carbon nanotube forest is fixed; A rotating part for fixing both sides of the fixing rod and twisting the carbon nanotube surface to form a carbon fiber; And a holder for mounting the rotating part.

In the present invention, the moving part is characterized in that it moves the collecting part at a speed of 1 to 10 mm per second.

In the present invention, the tension part is a rod for imparting tension to the carbon fiber; And a plate for fixing the rod and being attached to and detached from the body.

All matters mentioned in the carbon fiber manufacturing method and manufacturing apparatus using dry spinning are applied equally unless contradictory.

The carbon fiber manufacturing method and manufacturing apparatus using dry spinning of the present invention can produce an optimal carbon nanotube forest for manufacturing carbon fibers, and thus, carbon fibers can be manufactured with excellent yield.

In addition, the carbon fiber manufacturing method and manufacturing apparatus using dry spinning of the present invention has a strong Van der Waals' force between each of the carbon nanotubes forming the surface of the carbon nanotubes, resulting in high density. And thus it is possible to manufacture carbon fibers having excellent strength.

The effects of the present invention are not limited to the effects mentioned above, and other effects that are not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a block diagram schematically showing a carbon fiber manufacturing method using dry spinning of the present invention.
2 is a diagram schematically showing a carbon nanotube forest used in the method for manufacturing carbon fibers using dry spinning of the present invention.
Figure 3 is a view schematically showing the step (S2) of the carbon fiber manufacturing method using the dry spinning of the present invention.
Figure 4 is a view schematically showing the step (S3) of the carbon fiber manufacturing method using the dry spinning of the present invention.
Figure 5 is a view schematically showing the step (S4) of the carbon fiber manufacturing method using the dry spinning of the present invention.
6 is a view schematically showing the step (S5) of the method for manufacturing carbon fibers using dry spinning of the present invention.
7 is an SEM image of carbon fibers manufactured by the method of manufacturing carbon fibers using dry spinning of the present invention.

Terms used in the present specification have selected general terms that are currently widely used as possible while considering functions in the present invention, but this may vary depending on the intention or precedent of a technician working in the field, the emergence of new technologies, and the like. In addition, in certain cases, there are terms arbitrarily selected by the applicant, and in this case, the meaning of the terms will be described in detail in the description of the corresponding invention. Therefore, the terms used in the present invention should be defined based on the meaning of the term and the overall contents of the present invention, not a simple name of the term.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in this application. Does not.

The numerical range includes the numerical values defined in the above range. All maximum numerical limits given throughout this specification include all lower numerical limits as if the lower numerical limits were expressly written. All minimum numerical limits given throughout this specification are inclusive of all higher numerical limits as if the higher numerical limits were expressly written. All numerical limits given throughout this specification will include all better numerical ranges within the wider numerical range, as if the narrower numerical limits were expressly written.

Carbon fiber manufacturing method using dry spinning

The present invention provides a method for producing carbon fibers using dry spinning comprising the following steps.

(S1) preparing a carbon nanotube forest composed of carbon nanotubes;

(S2) fixing one surface of the carbon nanotube forest to a carbon fiber supply unit and fixing the other surface to a collecting unit;

(S3) forming a film-shaped carbon nanotube layer by spinning the collecting portion at a rate of 1 to 10 mm per second; And

(S4) manufacturing a carbon fiber by rotating the collecting part 360 ° to twist the surface of the carbon nanotube.

The term “carbon nanotube (CNT)” used in the present invention refers to an allotrope of carbon having a cylindrical nanostructure, and has excellent mechanical properties, thermal properties, and electrical properties.

In the present invention, the step (S1) may be a step of manufacturing a carbon nanotube forest composed of carbon nanotubes.

More specifically, the carbon nanotube forest may be manufactured by the following steps.

(S1A) depositing alumina (aluminum oxide, Al ₂ O ₃ ) on one surface of a silicon (SiO ₂ ) substrate to a thickness of 1 to 5 nm;

(S1B) depositing an iron (Fe) catalyst to a thickness of 2 to 3 nm on one surface of the alumina; And

(S1C) preparing a carbon nanotube forest by using a chemical vapor deposition (CVD) method of carbon nanotubes on one surface of the iron catalyst.

In the step (S1A), the alumina is preferably coated to a thickness of 1 to 5 nm. More specifically, when the alumina is coated with a thickness of less than 1 nm, the alumina is formed too thin, so that the effect due to the alumina does not appear, and when the alumina is coated more than 10 nm, the alumina layer and the carbon nanotube Dry spinning cannot be performed due to the increased bonding force. Therefore, the alumina is preferably coated to a thickness of 1 to 5 nm, and most preferably may be coated to a thickness of 2 to 4 nm.

In the step (S1B), an iron (Fe) catalyst may be deposited to a thickness of 2 to 3 nm on the upper surface of the alumina deposited on one surface of the silicon (SiO ₂ ) substrate.

The iron catalyst may be deposited by an electron beam coating system, and the electron beam coating system includes an evaporating chamber, an evaporate control system, and a power supply system. ) And a vacuum system.

More specifically, the alumina-coated silicon substrate is inserted into the evaporation chamber, and a pressure of 4 x 10 ^-6 to 5 x 10 ^-6 torr is applied. Next, a high voltage of 4 to 6 kV is applied, and an iron catalyst is deposited on the alumina upper surface.

An iron catalyst is deposited by the electron beam coating system, and an alloy may be formed between the alumina and the iron catalyst due to heat generated to form a catalytic metal island during carbon nanotube synthesis. The alloy may be formed to a thickness of 1 to 3 nm. Due to the alloy, the bonding force between the carbon nanotubes coated in the (S1C) step may be reduced, so that the yield of forming carbon fibers may be significantly increased.

Finally, in the (S1C) step, a carbon nanotube forest can be prepared by using a chemical vapor deposition (CVD) method of carbon nanotubes on one surface of the iron catalyst deposited in the (S1B) step.

In the present invention, the step (S2) may be a step of fixing one surface of the carbon nanotube forest to the carbon fiber supply unit and fixing the other surface to the collecting unit, and the step (S3) includes 1 to 1 per second of the collecting unit. It may be a step of forming a film-shaped carbon nanotube layer by spinning at a speed of 10 mm.

In the step (S3), the surface of the carbon nanotube may be 100 to 500 mm. When the carbon nanotube side is formed to be less than 100 mm, it is difficult to manufacture the finally produced carbon fiber due to the short length, and when the carbon nanotube side is formed to exceed 500 mm, the carbon nanotube side is Since the applied tension is reduced and the surface of the carbon nanotubes may be cut, it is preferable that the surface of the carbon nanotubes has a length of 100 to 500 mm.

The surface of the carbon nanotubes prepared in step (S3) may be formed by the action of attractive force due to the Van der Waals' force existing between the carbon nanotubes. Due to the Van der Waals force, the carbon nanotubes may be formed with a high density, and thus the strength of the finally produced carbon fiber may be remarkably improved.

In the present invention, the step (S4) may be a step of manufacturing a carbon fiber by twisting the surface of the carbon nanotube by rotating the collecting part by 360°.

More specifically, the collecting part may be rotated 360° once per second to prepare a twisted carbon fiber by twisting the surface of the carbon nanotube.

The present invention may further include a step (S5) of applying tension to the carbon fiber produced in the step (S4) after completion of the step (S4).

More specifically, in the step (S5), the carbon fiber produced in the step (S4) is placed on a rod formed on one surface of the plate, thereby imparting tension due to the frictional force according to the angle of the carbon fiber. can do.

The method for manufacturing carbon fibers using dry spinning of the present invention can produce an optimal carbon nanotube forest for manufacturing carbon fibers, and thus, carbon fibers can be manufactured with excellent yield.

In addition, a strong Van der Waals' force exists between each of the carbon nanotubes forming the surface of the carbon nanotubes, so that carbon fibers having high density and excellent strength can be manufactured.

Carbon fiber manufacturing equipment

The present invention provides a carbon fiber manufacturing apparatus for manufacturing carbon fibers using the above manufacturing method.

More specifically, the body portion; A supply unit located on one side of the body unit and configured to supply a carbon nanotube forest; A collecting part for forming a carbon nanotube surface by spinning the carbon nanotube forest fixed to the supply part and producing a carbon fiber; A moving part positioned in the longitudinal direction of the body part and moving the collecting part at a constant speed; And a tension part for imparting tension to the carbon fiber produced by the collecting part.

The body portion may have a shape for maintaining the shape of the carbon fiber manufacturing apparatus.

In addition, a groove for attaching and detaching the tension part may be formed in a longitudinal direction, and the length and width of the groove may be easily changed according to the tension part.

In the present invention, the carbon fiber supply unit may be fixed to one side of the carbon nanotube press for supplying the material of the carbon fiber.

The carbon fiber supply unit may have a height of 100 to 130 mm, and preferably may be formed to have a height of 110 to 120 mm.

In the present invention, the collecting portion may be fixed to the other surface of the carbon nanotube forest, and may form the carbon nanotube surface while being moved by the moving portion.

The collecting portion may be formed of an acrylic or steel material, but is not limited thereto.

The collecting part may include a fixing rod to which the other surface of the carbon nanotube forest is fixed; A rotating part for fixing both sides of the fixing rod and twisting the carbon nanotube surface to form a carbon fiber; And a cradle for mounting the rotating part.

The fixing rod may supply a material for forming the carbon nanotube surface by fixing the other surface of the carbon nanotube forest.

The rotating part may rotate the surface of the carbon nanotube 360° once per second. As the rotating part rotates, the carbon nanotubes may be twisted to form a carbon fiber having a predetermined thickness.

The rotating part fixes both sides of the fixing rod, and may be formed in a “c” shape. More specifically, grooves are formed at both ends of the “c” shape of the rotating part, and the fixing rod may be inserted into the groove to fix the fixing rod.

The cradle may mount the rotating part. More specifically, the cradle may be mounted by fixing the rotating part using a rotatable screw, may be mounted to be inserted into a rotatable rotating shaft, and is not limited thereto as long as it is fixed and mounted in a rotatable form.

In the present invention, the moving part may move the collecting part at a speed of 1 to 10 mm per second. The moving part may move at a constant speed to apply tension to the carbon nanotube forest fixed to the collecting part, thereby forming a carbon nanotube surface.

The moving unit may be moved by using a roller or an additional motor is installed, and a method capable of moving the collecting unit at a constant speed is not limited thereto.

In the present invention, the tension unit may impart tension to the carbon fiber manufactured by the collecting unit.

The tension part may be manufactured in a form that can be detachably attached to one side of the body part in the longitudinal direction. More specifically, the tension part may be twisted on the surface of the carbon nanotube by the rotation part to be made of the carbon fiber, and then attached to one side of the body part.

The tension part may include a rod for imparting tension to the carbon fiber; And a plate for fixing the rod and being attached to and detached from the body.

The rod may apply a frictional force according to the angle of the manufactured carbon fiber, that is, a tension to a portion where the carbon fiber and the rod abut.

The plate may have a rectangular planar shape, but is not limited as long as the rod is fixed and detachable to the body portion.

Since the carbon fiber manufacturing apparatus of the present invention does not require specific conditions such as high temperature and high pressure, it is easy to apply to mass production industries, and the physical properties of carbon fibers can be improved through a post-treatment process in which a simple module is inserted into the process. It can also be used in small businesses.

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to embodiments described below in detail. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in a variety of different forms, and only the embodiments make the disclosure of the present invention complete, and common knowledge in the technical field to which the present invention pertains. It is provided to inform a person having a complete scope of the invention, and the invention is only defined by the scope of the claims.

The reagents and solvents mentioned below were purchased from Taewon Science Co., Ltd. unless otherwise specified, and the electron beam coating system equipment used in the examples was SHE-6T-350D (Samhan Thin Film Vacuum ( Note)) was used to perform the experiment, and the chemical vapor deposition equipment used in the examples was an electric furnace (Izak Co., Ltd.).

Preparation Example 1. Preparation of carbon nanotubes

The carbon nanotubes used in the present invention were manufactured by a low pressure chemical vapor deposition (LP-CVD) method.

More specifically, the inside of the chamber of the reactor in which the low pressure chemical vapor deposition is performed was put as a substrate for growing carbon nanotubes, and the inside of the chamber was maintained in an environment of 10 ^-4 torr. And, while passing argon (400 sccm) to the reactor was maintained at 520 ℃. Then, hydrogen (H ₂ ) was introduced into the chamber at 500 sccm for 1 minute to form catalyst particles having a uniform size to perform a pretreatment process. After completing the pretreatment process, argon was flowed at a rate of 400 sccm for 4 minutes, and the temperature was maintained at 700°C. In addition, acetylene (ethyne, C ₂ H ₂ ) at 200 sccm and hydrogen (H ₂ ) at 400 sccm were simultaneously flowed into the chamber for 30 minutes to grow carbon nanotubes. Finally, argon (400 sccm) was flowed and cooled to room temperature to prepare a carbon nanotube.

Example 1. Carbon fiber production

1. Manufacture of carbon nanotube forest

The silicon (SiO ₂ ) substrate was coated by depositing alumina (aluminum oxide, Al ₂ O ₃ ) to a thickness of 3 nm. Then, the iron catalyst was coated to a thickness of 3 nm using an electron beam coating system in which a high voltage of 5 kV was applied in a pressure environment of 4 x 10 ^-6 on the upper surface of the alumina layer. At this time, an alloy was formed between the alumina and the iron catalyst. Finally, a carbon nanotube forest was prepared by coating the carbon nanotube prepared in Preparation Example 1 on the upper surface of the iron catalyst layer.

2. Carbon fiber manufacturing

One side of the prepared carbon nanotube forest was fixed to the carbon fiber supply unit of the carbon fiber manufacturing apparatus, and the other side was fixed to the collecting unit. While moving the collecting part at a speed of 7 Mm per second, a film-shaped carbon nanotube surface was formed by 260 mm. Next, the carbon fiber of the present invention was manufactured by rotating the collecting part connected to the carbon nanotube surface several times by 360°. Finally, the tension was applied to the portion where the carbon fiber and the rod abutted by placing it on the rod of the tension portion, and the result is shown in FIG. 7.

Referring to FIG. 7, it can be seen that the surface of the manufactured carbon fiber is smooth and evenly manufactured.

From the above description, it will be understood that those skilled in the art belonging to the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention. In this regard, the embodiments described above are illustrative in all respects, and should be understood as non-limiting.

Carbon nanotube face: 10
Carbon fiber: 20
Body: 100
Home: 110
Supply Department: 200
Collecting part: 300
Fixed rod: 310
Rotating part: 320
Mount: 330
Moving part: 400
Tension part: 500
Rod: 510
Plate: 520

Claims (11)

(S1) preparing a carbon nanotube forest composed of carbon nanotubes;
(S2) fixing one surface of the carbon nanotube forest to a carbon fiber supply unit and fixing the other surface to a collecting unit positioned on the moving unit;
(S3) forming a film-shaped carbon nanotube layer by spinning the collecting part apart from the supply part at a rate of 1 to 10 mm per second through the moving part; And
(S4) manufacturing a carbon fiber by twisting the surface of the carbon nanotube by rotating the collecting part by 360 °. A method for producing carbon fiber using dry spinning, comprising: a. The method of claim 1,
The carbon fiber manufacturing method using dry spinning, characterized in that it further comprises a; (S5) step of imparting tension to the carbon fiber prepared in the step (S4). The method of claim 1,
The carbon nanotube forest,
(S1A) depositing alumina (aluminum oxide, Al ₂ O ₃ ) on one surface of a silicon (SiO ₂ ) substrate to a thickness of 1 to 5 nm;
(S1B) depositing an iron (Fe) catalyst to a thickness of 2 to 3 nm on one surface of the alumina; And
(S1C) preparing a carbon nanotube forest using a chemical vapor deposition (CVD) method of carbon nanotubes on one surface of the iron catalyst; including,
A method for producing carbon fiber using dry spinning, characterized in that an alloy of 1 to 3 nm is formed between the alumina and the iron catalyst. The method of claim 1,
The carbon fiber manufacturing method using dry spinning, characterized in that the carbon nanotube surface is formed in a length of 100 to 500 mm in the step (S3). The method of claim 1,
Carbon using dry spinning, characterized in that the carbon nanotube surface produced in step (S3) is formed by the action of attractive force by Van der Waals' force existing between the carbon nanotubes. Fiber manufacturing method. The method of claim 1,
The carbon fiber manufacturing method using dry spinning, characterized in that in the step (S4), the collecting unit rotates 360 ° once per second. Body part;
A supply unit located on one side of the body unit and configured to supply a carbon nanotube forest;
A collecting part for forming a carbon nanotube surface by spinning the carbon nanotube forest fixed to the supply part and producing a carbon fiber;
A moving part for moving the collecting part at a constant speed; And
A carbon fiber manufacturing apparatus comprising: a tension unit for imparting tension to the carbon fibers manufactured by the collecting unit. The method of claim 7,
The collecting part,
A fixing rod to which the other surface of the carbon nanotube forest is fixed;
A rotating part for fixing both sides of the fixing rod and twisting the carbon nanotube surface to form a carbon fiber; And
A carbon fiber manufacturing apparatus comprising: a cradle for mounting the rotating part. The method of claim 7,
The moving unit carbon fiber manufacturing apparatus, characterized in that to move the collecting unit at a speed of 1 to 10 mm per second. The method of claim 7,
The tension part,
A rod for imparting tension to the carbon fiber; And
A carbon fiber manufacturing apparatus comprising: a plate for fixing the rod and attaching or detaching to the body.
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