KR20220157190A - Method for shaping article using cnt coating fiber - Google Patents

Abstract

Provided are a method for molding objects or articles using CNT-coated fibers, such as a conductive fiber, and articles manufactured therefrom. The molding method comprises the following steps of: preparing the CNT-coated fibers coated with CNTs on fibers; providing the CNT-coated fibers on a base to form a CNT fiber layer; forming a pre-polymer layer on the CNT fiber layer; and curing the pre-polymer layer by directly applying power to at least one of the CNT fiber layer and the base.

Description

Method of forming an object using CNT coated fiber {METHOD FOR SHAPING ARTICLE USING CNT COATING FIBER}

The present invention relates to a method for forming an object using fibers. In detail, it relates to a method of forming an object or an article using a fiber coated with carbon nanotubes (CNT), such as a conductive fiber, and an article manufactured therefrom.

Fiber Reinforced Plastic (FRP) refers to a plastic material having improved mechanical strength by using fibers as reinforcing materials. Examples of fibers used as reinforcing materials include carbon fibers and glass fibers.

For example, carbon fiber reinforced plastic (CFRP) using carbon fiber as a reinforcing material has strength 10 times higher than that of iron, yet weighs only about 20%, and has excellent chemical resistance and heat resistance. In addition, it is attracting attention as an alternative to metal because of its excellent mechanical stability such as corrosion-free and low expansion rate.

Meanwhile, research is being conducted to further improve mechanical properties and/or chemical properties of an article to which a reinforcing material is applied by coating the surface of a fiber such as carbon fiber or glass fiber.

Republic of Korea Patent Publication No. 10-2013-0048050 Republic of Korea Patent Registration No. 10-1362026 Republic of Korea Patent Registration No. 10-2017278

As described above, various researches and developments have been conducted to reinforce the strength of articles using fibers having excellent mechanical and chemical stability. However, fibers generally used as reinforcing materials, such as carbon fibers, have a problem in that they are easily damaged by external force during the manufacturing process. Due to the brittle properties of carbon fiber during the manufacturing process, it is necessary to develop a process for manufacturing an article reinforced with carbon fiber.

Accordingly, the problem to be solved by the present invention is to provide a method for producing coated reinforcing fibers having excellent moldability. In particular, it is to provide a method for producing a reinforcing fiber to which a CNT coating is applied.

Another problem to be solved by the present invention is to provide coated reinforcing fibers having excellent formability. In particular, it is to provide CNT-coated CNT-coated fibers.

Another problem to be solved by the present invention is to provide a method for forming an article using a CNT-coated fiber.

Another problem to be solved by the present invention is to provide an article with reinforced strength and the like using CNT-coated fibers.

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

A method of molding an object according to an embodiment of the present invention for solving the above problems is a molding method using CNT fibers, comprising the steps of preparing a CNT-coated fiber coated with CNT on a fiber, the CNT-coated fiber on a base. providing a CNT fiber layer to form a CNT fiber layer, forming a prepolymer layer on the CNT fiber layer, and directly applying power to at least one of the CNT fiber layer and the base to cure the prepolymer layer.

The fiber may include at least one of an insulating fiber and a conductive fiber, the insulating fiber may include a glass fiber, and the conductive fiber may include a carbon fiber.

Preparing the CNT-coated fibers may include spraying or immersing the fibers in a mixed solution for CNT coating.

In addition, the mixed solution may be used to coat the surface of the fiber with CNTs, including CNT particles or a growth solution for directly growing CNTs.

The preparing of the CNT-coated fibers may further include curing or semi-curing the coating layer by directly heating the fibers.

When the base is a conductor, the step of insulating the surface of the base before forming the CNT fiber layer may be further included.

The base includes a cylindrical article having a hollow inside, and forming the CNT fiber layer on the base includes forming the CNT fiber layer on the inside of the base or forming the CNT fiber layer on the outside of the base. can include

Forming the CNT fiber layer on the outside of the base includes moving and reeling the CNT-coated fibers around the tubular article, or rotating the tubular article and stretching the CNT-coated fibers It may include a reeling step.

Forming the CNT fiber layer inside the base may include injecting the CNT-coated fibers into an inner space through an opening of the tubular article.

The forming of the prepolymer layer includes providing a polymerization solution on the CNT fiber layer using a spray nozzle, wherein the spray nozzle has a first nozzle through which the polymerization solution is sprayed and a second spray hole through which gas is sprayed. It may contain nozzles.

The forming of the prepolymer layer may include providing a polymerization solution on the CNT fiber layer using a spray nozzle, and the inside of the chamber in which the polymerization solution is sprayed may be in an atmosphere higher than atmospheric pressure.

The base may include a tubular article having an empty inside, and the curing of the prepolymer layer may include measuring an internal temperature of the tubular article and controlling power.

Other embodiment specifics are included in the detailed description.

According to embodiments of the present invention, reinforcing fibers having brittle properties may be reinforced by containing carbon nanotube particles in a polymer coating layer such as epoxy, and moldability may be improved.

In addition, the formability of an article or object reinforced with reinforcing fibers can be improved by direct heating by applying power to the article and carbon fiber using the high electrical conductivity of the coated fiber, and curing the coating layer through this.

Effects according to the embodiments of the present invention are not limited by the contents exemplified above, and more diverse effects are included in the present specification.

1 is a flow chart showing process steps according to an embodiment of the present invention.
Figure 2 is a schematic process diagram showing the step of preparing the coated fiber of Figure 1.
Figure 3 is a schematic diagram of the coated fiber prepared through the process of Figure 2.
Figure 4 is a flow chart showing the molding step of the object of Figure 1.
5 is a process schematic diagram showing the insulation processing step of FIG. 4 .
6 is a schematic process diagram showing a step of winding the fiber of FIG. 4 .
Figure 7 is a process schematic diagram showing the step of applying the epoxy of Figure 4.
FIG. 8 is an arrangement layout of injection ports of the injection nozzle of FIG. 7 .
9 is a schematic process diagram showing the epoxy curing step of FIG. 4 .
10 is a schematic process diagram showing an epoxy curing step in a method for molding an object according to another embodiment of the present invention.
11 is a schematic process diagram showing an epoxy curing step in a method for molding an object according to another embodiment of the present invention.
12 and 13 are process schematics showing steps of forming an object according to another embodiment of the present invention.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only the embodiments make the disclosure of the present invention complete, and those skilled in the art in the art to which the present invention belongs It is provided to fully inform the person of the scope of the invention, and the invention is only defined by the scope of the claims. That is, various changes may be made to the embodiments provided by the present invention. The embodiments described below are not intended to be limiting on the embodiments, and should be understood to include all modifications, equivalents or substitutes thereto.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used in a meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless explicitly specifically defined.

In this specification, 'and/or' includes each and every combination of one or more of the recited items. In addition, singular forms also include plural forms unless otherwise specified in the text. As used herein, 'comprises' and/or 'comprising' does not exclude the presence or addition of one or more other elements other than the recited elements. A numerical range expressed using 'to' indicates a numerical range including the values listed before and after it as the lower limit and the upper limit, respectively. 'About' or 'approximately' means a value or range of values within 20% of the value or range of values set forth thereafter.

The size, thickness, width, length, etc. of the components shown in the drawings may be exaggerated or reduced for convenience and clarity of explanation, so the present invention is not limited to the illustrated form.

The spatially relative terms 'above', 'upper', 'on', 'below', 'beneath', 'lower', etc. are not included in the drawings. As shown, it can be used to easily describe the correlation between one element or component and another element or component. Spatially relative terms should be understood as encompassing different orientations of elements in use in addition to the orientations shown in the figures. For example, when elements shown in the figures are turned over, elements described as 'below' or 'below' other elements may be placed 'above' the other elements. Accordingly, the exemplary term 'below' may include directions of both down and up.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a flow chart showing process steps according to an embodiment of the present invention.

Referring to FIG. 1 , the process according to the present embodiment may include a step of manufacturing coated fibers (S100) and a step of forming an article using the coated fibers (S200).

Specifically, the manufacturing step of the coated fiber (S100) is a step of transferring the fiber (S110), a step of providing a coating solution to the fiber (S120), a step of semi-curing the coating layer by direct heating (S130), and preparing the coated fiber. It may include a step (S150) of doing, and may further include a step (S140) of determining whether the coating process is complete.

In addition, the forming of the article using the coated fibers (S200) includes determining the coating position of the reinforcing fibers (S210), forming a fiber coating layer on the surface of the base article using the coated fibers (S230), and A step of providing a polymerization solution (S240), precipitating or permeating the polymerization solution (S250), and directly heating the coating layer (S260), including an insulation treatment step (S220) and/or a molding process A step of determining whether to complete (S270) may be further included.

Although not shown in the drawing, a water wash step may be further included between each step.

Hereinafter, the manufacturing step (S100) of the above-described coated fiber and the molding step (S200) of the article will be described in more detail.

Figure 2 is a schematic process diagram showing the step (S100) of preparing the coated fiber of Figure 1. Figure 3 is a schematic diagram of the coated fiber prepared through the process of Figure 2.

Further referring to FIGS. 2 and 3 , the manufacturing step (S100) of the coated fiber may be performed using a roll-to-roll process. The process equipment may include an unwinding roll 910 and a winding roll 920 . The base fiber 100 is unwound through the unwinding roll 910 and the base fiber 100 may be transferred in the direction of the winding roll 920 through the plurality of transfer rolls 930 (S110).

In an exemplary embodiment, the base fiber 100 includes a conductive fiber 100a and may further include a non-conductive fiber 100b. For example, the conductive fiber 100a may include carbon fiber, and the non-conductive fiber 100b may include glass fiber. The base fiber 100 may be a yarn in which a conductive fiber 100a and a non-conductive fiber 100b are twisted with each other.

3 illustrates a case in which one filament of the conductive fiber 100a and one filament of the non-conductive fiber 100b are twisted with each other, but the present invention is not limited thereto, and in another embodiment, the conductive fiber 100a and the non-conductive fiber 100b ) may form yarns in different shapes. In another embodiment, the base fiber 100 may be made of only conductive fibers, or a yarn may be formed only of a plurality of conductive fiber filaments.

A coating liquid may be provided on the surface of the base fiber 100 transported through the unwinding roll 910, the winding roll 920, and the transfer rolls 930 (S120). 2 is a roll-to-roll process in which a coating liquid is provided using a coating liquid spray nozzle 950 (front end of FIG. 2), and a base fiber 100 is immersed in a coating bath 960 containing the coating liquid to provide a coating liquid (Fig. The case in which all of the subsequent stages of 2) are performed is exemplified.

However, the present invention is not limited thereto, and in the step of providing the coating solution in another embodiment (S120), the immersion coating process using the coating bath 960 is performed first, and the coating process using the coating liquid spray nozzle 950 is performed later. can be performed In another embodiment, the step of providing the coating liquid ( S120 ) may be performed using only the coating liquid spray nozzle 950 or only the coating bath 960 . In another embodiment, at least one of the coating process using the coating liquid spray nozzle 950 and/or the immersion coating process using the coating bath 960 may be performed a plurality of times.

In the present specification, the polymer, polymer coating layer, or coating layer, or coating solution used in the step of manufacturing the coated fiber (S100) is used in the step of forming an article (S200) to be described later, or the polymer, or the polymer coating layer, or In order to distinguish the coating layer or the coating liquid, it may be referred to as a first polymer, a first polymer coating layer, a first coating layer, or a first coating liquid. Similarly, in the molding step (S200) of the article, it may be referred to as a second polymer, a second polymer coating layer, a second coating layer, or a second coating liquid.

First, the coating liquid providing step using the coating liquid spray nozzle 950 located at the front end will be described.

The base fiber 100 transported through the unwinding roll 910 and the transfer rolls 930 may be provided with a coating liquid on the surface of the base fiber 100 using the coating liquid spray nozzle 950 (S120). FIG. 2 illustrates a case in which the base fiber 100 is transported, the washing nozzle sprays the washing liquid, and then the coating liquid is provided using the coating liquid spray nozzle 950.

The coating liquid spray nozzle 950 may spray the coating liquid onto the surface of the base fiber 100 . The coating solution includes carbon nanotube (CNT) particles to form a coating layer containing carbon nanotubes on the surface of the base fiber 100, or by growing carbon nanotubes on the surface of the base fiber 100 to form a carbon nanotube. It may be configured to form a coating layer containing a. That is, the coating solution may include the carbon nanotube particles themselves or a precursor of the carbon nanotubes. When the coating solution includes carbon nanotube particles, the carbon nanotube particles may be included in an amount of about 0.1wt% to 10wt% based on the total weight of the coating solution. On the other hand, when the coating solution includes a precursor of carbon nanotubes, examples of the precursor may include hydrocarbon materials, but the present invention is not limited thereto.

In addition, the coating solution may further include a base solution in which the aforementioned carbon nanotube particles or precursors thereof are dispersed. The base solution may include a polymer such as epoxy. As a solvent, ethanol or the like may be used, but the present invention is not limited thereto.

In addition, the coating liquid injection nozzle 950 may spray a mixture of the above-described polymer, carbon nanotube or precursor thereof, and a solvent in a mixed liquid state. However, the present invention is not limited thereto, and a plurality of coating liquid injection nozzles are provided so that each of the plurality of nozzles sprays a polymer or polymer solution, carbon nanotube or a precursor thereof, and mixes them on the surface of the base fiber 100. may be configured.

The mechanical properties of the coated fiber 120 may be further improved by allowing the coated fiber 120 to include the carbon nanotube particles 11 having a size of several tens of nm to several hundred nm.

Forming a semi-cured coating layer 12 by heating the base fiber 100 in a state in which a coating solution containing a polymer and carbon nanotubes (or precursors thereof) 11 is applied to the surface of the base fiber 100 ( S130) may be performed.

In an exemplary embodiment, the direct heating (S130) may be performed using a plurality of ground points 970a and 970b and a first power source 940a. 2 illustrates a case of using a transfer roll located at a predetermined position as the grounding points 970a and 970b, but the present invention is not limited thereto. In addition, when at least some of the ground points 970a are located before the coating liquid spray nozzle 950 as in the embodiment of FIG. 2, the base fiber 100 to which the coating liquid is sprayed may be already heated to a predetermined temperature.

Specifically, the first grounding point 970a and the second grounding point 970b are provided at a plurality of positions before the coating liquid is applied by the coating liquid spray nozzle 950, while the coating liquid is applied, or immediately after the coating liquid is applied. It can be. In addition, the first power source 940a may be applied to the first ground point 970a and the second ground point 970b. Accordingly, current may flow through the electrically conductive base fiber 100 and heat may be generated.

In this step (S130), the heating temperature of the base fiber 100 may be about 40 °C to 200 °C, or about 60 °C to 180 °C, or about 80 °C to 160 °C. In the above temperature range, the coating solution containing a polymer such as epoxy may be semi-cured while maintaining predetermined elasticity and reactivity without being completely cured. For example, in this step (S130), the semi-cured coating layer 12 may form a soft layer. Through the above process, it is possible to provide a fiber on which a coating layer is formed, that is, the coated fiber 120 . In other words, the coating layer 12 of the coated fibers 120 may be in a state of a prepolymer layer (eg, a first prepolymer layer) in which room for additional curing reaction remains.

As in the present embodiment, the base fiber 100 is directly heated at the same time as, or just before and after the coating solution containing carbon nanotubes or carbon nanotube precursors is applied, so that a separate heating chamber, heat treatment chamber, or curing Semi-curing of the polymer coating layer can be performed without passing through the chamber. Therefore, equipment simplification of the roll-to-roll process can be achieved.

In addition, if the fibers are transported too much for curing (or semi-curing) in a state where the polymer coating layer 12 is not formed, the reinforcing fibers may be damaged. For example, when the reinforcing fibers include carbon fibers, the fibers may be damaged due to brittle properties. However, the above problems can be solved by substantially simultaneously providing the coating liquid and semi-curing while minimizing the transfer of the base fibers 100 using the transfer rolls as in the present embodiment.

In particular, since the time from providing the coating liquid to semi-curing is short, the base fiber 100 can be semi-curing in a state where a sufficient amount of the coating liquid exists on the surface, thereby forming a semi-curing coating layer 12 having a sufficient thickness. Unlike the present embodiment, if the fiber is loaded into a separate heat treatment chamber after providing the coating solution in the roll-to-roll process, it is difficult to form a coating layer having a sufficient thickness because a large amount of the coating solution is lost during the transfer process.

In addition, although the present invention is not limited thereto, even when the coating solution includes a precursor for the growth of carbon nanotubes, the size of the carbon nanotubes grown after curing/semi-curing increases as the contact time of the precursor in the air increases. and content may not be sufficient. However, the above problem can be solved by heating the base fiber 100 using the ground points 970a and 970b located immediately before, during, or immediately after the application of the coating solution, as in the present embodiment.

Meanwhile, the step of providing the coating solution using the coating bath 960 located at the rear end will be described. In the present embodiment, the provision of the coating liquid using the coating bath 960 (S120) and the semi-curing step (S130) provide the coating liquid using the coating liquid spray nozzle 950 as described above (S120), and perform semi-curing ( It may be performed to reinforce the coating layer by being performed after S130). Although the present invention is not limited thereto, according to the present embodiment, a plurality of coating layers may be formed.

However, the present invention is not limited thereto, and as described above, the steps of providing the coating liquid and semi-curing may be performed using only one of the coating liquid spray nozzle 950 and the coating bath 960 .

The base fiber 100 transported through the transfer rolls 930 or the fiber 120 on which the semi-cured coating layer 12 is formed is immersed in the coating bath 960, and a coating liquid may be provided on the surface (S120). . 2 illustrates a case in which the base fiber 100 is immersed in a coating bath 960 and then immersed in a washing bath.

The coating liquid may be accommodated in the coating bath 960 . As described above, the coating solution includes carbon nanotube particles or a precursor of carbon nanotubes. In addition, the coating solution may further include a base solution. The base solution may include a polymer such as epoxy and ethanol.

Forming a semi-cured coating layer 12 by heating the base fiber 100 in a state in which a coating solution containing a polymer and carbon nanotubes (or precursors thereof) 11 is applied to the surface of the base fiber 100 ( S130) may be performed.

In an exemplary embodiment, the direct heating ( S130 ) may be performed using a plurality of ground points 980 and a second power source 940b. 2 illustrates a case in which transfer rolls located at predetermined positions are used as the contact points 980, but the present invention is not limited thereto. In addition, as in the embodiment of FIG. 2, when the grounding point 980 is located before the base fiber 100 is introduced into the coating bath 960, the base fiber 100 immersed in the coating bath 960 is heated to a predetermined temperature. It may already be in a heated state. Accordingly, current may flow through the electrically conductive base fiber 100 and heat may be generated.

In this step (S130), the heating temperature of the base fiber 100 may be about 40 °C to 200 °C, or about 60 °C to 180 °C, or about 80 °C to 160 °C. In the above temperature range, the coating solution containing a polymer such as epoxy may be semi-cured while maintaining predetermined elasticity and reactivity without being completely cured. For example, in this step (S130), the semi-cured coating layer 12 may form a soft layer. Through the above process, it is possible to provide a fiber on which a coating layer is formed, that is, the coated fiber 120 . In other words, the coating layer 12 of the coated fibers 120 may be in a state of a prepolymer layer (eg, a first prepolymer layer) in which room for additional curing reaction remains.

In some embodiments, the providing of the coated fibers (S100) may further include determining whether or not the coating process is completed, for example, whether or not a uniform coating layer is formed (S140). If it is determined in this step (S140) that the coating layer is not uniformly formed, the coating solution may be provided again (S120) and semi-curing may be performed (S130).

In other embodiments, the coating may utilize plasma.

Next, the molding step (S200) of the article will be described. Figure 4 is a flow chart showing the forming step (S200) of the object of Figure 1. 5 is a schematic process diagram showing the insulation processing step (S220) of FIG. FIG. 6 is a schematic process diagram showing a step (S230) of winding the fiber of FIG. 4. 7 is a process schematic diagram showing the step (S240) of applying the epoxy of FIG. FIG. 8 is an arrangement layout of injection ports of the injection nozzle of FIG. 7 . 9 is a process schematic diagram showing the epoxy curing step (S260) of FIG.

4 to 9, the molding step (S200) of the object according to this embodiment is the step of determining the position of the coating layer using reinforcing fibers on the surface of the base article 200 or the base object to be molded ( S210). For example, the base article 200 is a tubular article having an inner space IS, and whether a reinforcing fiber layer is formed on the inner surface IS of the base article 200 or It may be determined whether to form a reinforcing fiber layer on the outer surface OS. Hereinafter, a case where a reinforcing fiber layer is formed on the outer surface of the base article 200 will be described as an example. The following process may be performed in a state in which the inner space IS of the base article 200 is sealed by a cap C or the like.

In some embodiments, when the base article 200 includes a material such as metal and has electrical conductivity, or the electrical conductivity has an excessively higher level of electrical conductivity than the coated fiber 120 manufactured through the process described above. In this case, the step of insulating the surface of the base article 200 (S220) may be performed. For example, when the electrical conductivity of the base article 200 is about 150% or more, about 200% or more, or about 250% or more higher than the electrical conductivity of the coated fiber 120, the insulation treatment may be performed.

An example of a method of insulating the surface of the base product 200 is not particularly limited, but may include, for example, a method of applying an oxidizing solution such as ozone (O ₃ ) to the surface of the base product 200 . When the base article 200 is made of a material such as aluminum, an oxide layer (AlO ₃ ) is formed on the surface through a reaction with ozone, and may exhibit a predetermined insulating property. However, the present invention is not limited thereto, and an additional passivation layer may be formed on the surface of the base product 200 instead of forming an oxide layer on the surface of the base product 200 .

Subsequently, a coated fiber layer 150 is formed on the outer surface of the base article 200 (S230). The coated fiber layer 150 may include the coated fiber 120 on which the coating layer containing the aforementioned carbon nanotubes is formed. Specifically, the coating fiber 120 may be formed by reeling the coated fiber 120 on the surface of the base article 200 using a reeling apparatus while the position of the base article 200 is fixed. The reeling device may be configured to move along the rail. Through this, the coated fiber layer 150 may be formed on the surface of the base article 200 on which the coated fiber 120 is reeled. In this step (S230), the coating layer 12 of the coated fiber 120 may still be in a soft prepolymer state.

Although not shown in the drawing, in another embodiment, the reeling device may form the coated fiber layer 150 by winding the coated fiber 120 on the surface while the base article 200 rotates in a fixed state.

In the case of general carbon fiber, it is substantially difficult to form a fiber layer through winding as in the present embodiment due to brittle characteristics. However, as in the present embodiment, a winding process using a reeling device may be adopted by forming a prepolymer layer on the surface of the carbon fiber and performing a winding process while maintaining the prepolymer state.

Subsequently, a polymer coating layer (eg, a second coating layer) 300 is formed on the coated fiber layer 150 (S240). Forming the application layer 300 may be performed by applying a polymerization solution on the coating fiber layer 150 . The polymerization solution may include a polymer solution. The polymer in the polymerization solution used in this step (S240) may include substantially the same polymer as the polymer used in the previous step of preparing the coated fibers 120. For example, the polymerization solution in this step (S240) may include an epoxy-based polymer. The solvent of the polymerization solution may include ethanol, but the present invention is not limited thereto. In this step (S240), the coating layer 12 of the coated fiber 120 in the fiber coating layer 150 may still be in a soft prepolymer state.

Also, as described above, the fiber coating layer 150 may be formed by winding or stacking the coating fibers 120. Therefore, the fiber coating layer 150 may have a very high porosity. Although the present invention is not limited thereto, the coating fiber 120 may have a thickness of about 50 nm to 500 μm, or about 500 nm to 400 μm, or about 1 μm to 300 μm.

Therefore, it may be desirable to ensure that the polymer solution sprayed from the spray nozzle device 20 sufficiently penetrates into the fiber coating layer 150 . To this end, the spray nozzle device 20 may include a first spray hole 20a and a second spray hole 20b. For example, the first nozzle 20a may inject a polymer solution including a polymer such as epoxy, and the second nozzle 20b may inject gas. Examples of the gas include air or an inert gas such as nitrogen (N ₂ ).

In addition, FIG. 8 illustrates a case where the first nozzles 20a and the second nozzles 20b are alternately arranged in the column direction and repeatedly arranged in the row direction, but the present invention is not limited thereto. In another embodiment, the first nozzles 20a and the second nozzles 20b may be alternately arranged in both the row and column directions.

By providing a gas providing strong pressure using the second nozzle 20b of the spray nozzle device 20, the polymerization solution can sufficiently penetrate or permeate into the fiber coating layer 150. The coating layer 300 may form a prepolymer.

In some embodiments, the atmosphere in the chamber may be formed to have a higher atmospheric pressure than atmospheric pressure in order to enhance the inflow of the polymer solution into the fiber coating layer 150 . For example, the pressure in the chamber may be 2 atm to 10 atm, or about 3 atm to 5 atm.

Subsequently, the above-described coating layer 300 is cured to form a polymer coating layer 350 (S260). In an exemplary embodiment, the step of forming the polymer coating layer 350 (S260) may be performed by direct heating by applying power source 840 to the fiber coating layer 150.

Specifically, the first heating point 821 and the second heating point 822 in the fiber coating layer 150 may be provided through the coating layer 300 . The fiber coating layer 150 may be heated by applying power 840 to the first heating point 821 and the second heating point 822 . 9 illustrates a case in which two heating points are provided, but the present invention is not limited thereto. In another embodiment, 3 or more heating points or 10 or more heating points may be provided.

As described above, since the fiber coating layer 150 has electrical conductivity as a whole, it can be heated while current flows through the fiber coating layer 150 . For example, the heating temperature of the fiber coating layer 150 may be about 500 °C to 1,000 °C, or about 600 °C to 900 °C, or about 700 °C to 800 °C.

The fiber coating layer 150 is heated, and the polymer in the coating layer 300, for example, epoxy is completely cured to form a hard polymer coating layer 350. In addition, in this step (S260), the coating layer 12 of the coated fiber 120 in the fiber coating layer 150, that is, the prepolymer coating layer 12 in a semi-cured state may also be cured together.

Unlike the present embodiment, if the coating layer of the coated fiber 120 is in a fully cured state, bonding between the fiber coating layer 150 and the polymer coating layer 350 may not be sufficient. However, as in the present embodiment, the coating layer 12 of the coating fiber 120 is intentionally maintained in a semi-cured state, and the coating layer 300 applied on the fiber coating layer 150 is cured and the coating fiber 120 is cured. By curing the coating layer 12, bonding strength between the fiber coating layer 150 and the polymer coating layer 350 may be improved.

Also, in some embodiments, an apparatus for molding an object may further include one or more temperature sensors 871 and 872. For example, a first temperature sensor 871 and a second temperature sensor 872 may be included. The temperature sensors 871 and 872 may be configured to measure the temperature inside the tubular base article 200 having the inner space IS. To this end, the temperature sensors 871 and 872 may be positioned partially through the base article 200 .

As described above, when the direct heating process of directly applying the power source 840 is performed to form the polymer coating layer 350, more precise temperature measurement may be required than measuring the ambient temperature inside the chamber. In particular, when the base article 200 is a cylindrical article having an empty space inside, as in the present embodiment, the temperature of the base article 200 and the layers stacked thereon are measured by measuring the temperature in the inner space IS. can be measured more accurately. To this end, the apparatus for shaping the object further includes a controller 810 , and application of power 840 , temperature sensing, and timing control thereof may be performed by the controller 810 . In some embodiments, the controller 810 may also control the injection nozzle device 20 used in the above-described step, the chamber pressure control device, and the polymerization solution application device.

As described above, in the method of forming the object according to the present embodiment, the coating fiber 120 including the semi-cured coating layer 12 is used to form the fiber coating layer 150 on the base article 200, and the coating layer 150 is formed thereon. After forming the coating layer 300 in a semi-cured or uncured state, power may be applied directly to the fiber coating layer 150 to completely cure the semi-cured coating layer 120 and the coating layer 300 together. In the case of reinforcing fiber materials such as carbon fibers, they have excellent mechanical properties, but miscibility with polymer materials may be problematic. However, according to the present embodiment, the above problem can be solved because the reinforcing fiber material can be firmly bonded to the polymer coating layer 350 .

Although the present invention is not limited thereto, the molded article manufactured according to this embodiment may have grooves and/or holes partially on its surface. The groove may be a residual trace of the first heating point 821 and/or the second heating point 822 formed by heating the fiber coating layer 150 directly with power, and the hole may be a first temperature sensor 871 And/or it may be a trace of penetration of the second temperature sensor 872 .

In some embodiments, the step of molding the object (S200) may further include a step (S270) of determining whether or not the molding process is completed after the formation of the polymer coating layer 350, for example, whether or not a uniform polymer coating layer 350 is formed. can If it is determined in this step (S270) that the polymer coating layer 350 is not sufficiently formed, a polymerization solution may be provided again (S240) and curing may be performed (S260).

Hereinafter, other embodiments of the present invention will be described. However, the description of the same or extremely similar configuration as the above-described manufacturing step of the coated fiber and molding step of the object will be omitted, and this will be clearly understood by those skilled in the art from the accompanying drawings.

10 is a schematic process diagram showing an epoxy curing step in a method for molding an object according to another embodiment of the present invention.

Referring to FIG. 10, in the step of curing the coating layer after forming the coating layer including epoxy, by applying power source 840 to the base article 200 instead of the fiber coating layer 150, The point of heating is different from the above-mentioned embodiment.

Specifically, the first heating point 821 and the second heating point 822 may be provided on or inside the base article 200 by penetrating the coating layer and the insulating layer. The base article 200 may be heated by applying power 840 to the first heating point 821 and the second heating point 822 .

Accordingly, the base article 200 is heated while current flows, and the polymer in the coating layer is cured to form the polymer coating layer 350 . In addition, in this step, the coating layer of the coated fiber in the fiber coating layer 150, that is, the prepolymer coating layer in a semi-cured state may also be cured together.

11 is a schematic process diagram showing an epoxy curing step in a method for molding an object according to another embodiment of the present invention.

Referring to FIG. 11 , in the step of curing the coating layer after forming the coating layer including epoxy, at least two heating points 821 and 822 are provided, and the first heating point 821 The silver fiber coating layer 150 is heated and the second heating point 822 heats the base article 200, which is different from the above-described embodiment.

12 and 13 are process schematics showing steps of forming an object according to another embodiment of the present invention.

First, referring to FIG. 12 , an insulating layer 230 is formed on the inner surface of a base article 200 and a coated fiber layer 150 is formed. As described above, the coated fiber layer 150 may include a semi-cured prepolymer coating layer and coated fibers including carbon nanotubes. Then, the coating layer 300 is formed on the coated fiber layer 150 using the spray nozzle device 21 . Since the coating layer 300 and the like have been described above, overlapping descriptions will be omitted.

Subsequently, referring to FIG. 13 , the coating layer 300 is cured to form a polymer coating layer 350 . As described above, formation of the polymer coating layer 350 may be performed by directly applying power to one or more heating points 821 and 822 . 13 illustrates a case in which heating points 821 and 822 are formed on the fiber coating layer 150, but the present invention is not limited thereto, and in another embodiment, at least one of the heating points is provided on the base article 200. It could be.

The fiber-reinforced molding manufactured according to the present invention described above may be applied to a wind turbine blade, a solar structure, an electronic enclosure, and the like.

Although the above has been described with reference to the embodiments of the present invention, this is only an example and does not limit the present invention, and those skilled in the art to which the present invention belongs will be able to It will be appreciated that various modifications and applications not exemplified above are possible.

Therefore, it should be understood that the scope of the present invention includes modifications, equivalents, or substitutes of the technical ideas exemplified above. For example, each component specifically shown in the embodiment of the present invention may be modified and implemented. And differences related to these modifications and applications should be construed as being included in the scope of the present invention as defined in the appended claims.

11: carbon nanotube particles
12: coating layer
120: coated fiber
150: carbon fiber layer
200: base article
230: insulating layer
350: polymer coating layer

Claims (11)

Preparing CNT-coated fibers coated with CNT fibers;
forming a CNT fiber layer by providing the CNT-coated fibers on a base;
forming a prepolymer layer on the CNT fiber layer; and
And curing the prepolymer layer by directly applying power to at least one of the CNT fiber layer and the base. According to claim 1,
The fiber includes at least one of an insulating fiber and a conductive fiber,
The insulating fiber includes glass fiber, and the conductive fiber includes carbon fiber. According to claim 1,
The step of preparing the CNT-coated fibers,
Including the step of spraying or immersing the mixed solution for CNT coating on the fiber,
The mixed solution includes CNT particles or a growth solution for directly growing CNTs,
A method for forming an object using CNT-coated fibers, which are used to coat CNTs on the surface of the fibers. According to claim 1,
The step of preparing the CNT-coated fiber, the method of forming the object further comprising the step of curing or semi-curing the coating layer by directly heating the fiber. According to claim 1,
If the base is a conductor, further comprising the step of insulating the surface of the base before the step of forming the CNT fiber layer, the method of forming an object using CNT-coated fibers. According to claim 1,
The base includes a cylindrical article with an empty interior,
Forming a CNT fiber layer on the base,
Forming a CNT fiber layer on the inside of the base, or forming a CNT fiber layer on the outside of the base, a method for molding an object using CNT-coated fibers. According to claim 6,
Forming a CNT fiber layer on the outside of the base,
Moving and reeling the CNT-coated fiber around the tubular article, or
A method of forming an object using CNT-coated fibers, comprising the step of rotating the tubular article and reeling the stretched CNT-coated fibers. According to claim 6,
Forming a CNT fiber layer on the inside of the base,
A method of forming an object using CNT-coated fibers comprising the step of injecting the CNT-coated fibers into an inner space through an opening of the tubular article. According to claim 1,
Forming the prepolymer layer includes providing a polymerization solution on the CNT fiber layer using a spray nozzle,
The injection nozzle includes a first injection hole through which the polymerization solution is injected, and a second injection hole through which gas is injected. According to claim 1,
Forming the prepolymer layer includes providing a polymerization solution on the CNT fiber layer using a spray nozzle,
Method for molding an object using a CNT-coated fiber in which the inside of the chamber for spraying the polymerization solution is an atmosphere higher than atmospheric pressure. According to claim 1,
The base includes a cylindrical article with an empty interior,
The curing of the prepolymer layer comprises the step of controlling power by measuring the temperature inside the tubular article, a method for forming an object using a CNT-coated fiber.

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