KR102467629B1 - Graphene wet spinning coagulating bath and method for manufacturing graphene oxide fiber using the same - Google Patents

Abstract

Provided is a graphene wet spinning coagulation bath and a method for manufacturing graphene oxide fibers including the same. A method for manufacturing a graphene oxide fiber according to the present invention includes preparing a graphene oxide dispersion containing a graphene oxide sheet and a dispersion medium, a coagulation solvent that pushes the dispersion medium, a crosslinking agent and a coagulation solvent that form a bridge between the graphene oxide sheets and preparing graphene oxide gel fibers by spinning the dispersion in a coagulation bath containing an emulsifier for mixing a crosslinking agent and drying the graphene oxide gel fibers. According to the present invention, in the manufacture of graphene oxide fibers using wet spinning, it is possible to provide an organic coagulation bath capable of controlling the shrinkage rate and drying rate of graphene oxide gel fibers during spinning. Accordingly, the prepared graphene oxide fibers may exhibit excellent structural stability and may be hybridized with various materials.

Description

Graphene wet spinning coagulating bath and method for manufacturing graphene oxide fiber using the same {Graphene wet spinning coagulating bath and method for manufacturing graphene oxide fiber using the same}

The present invention relates to a coagulation solution, and more particularly, to a coagulation solution for graphene wet spinning.

Nano carbon-based materials such as graphene and carbon nanotube (CNT) have excellent electrical properties, thermal properties, flexibility, and mechanical strength, so they are used as next-generation electronic materials, heat dissipation materials, and ultra-high strength structural materials. It is a high-tech material.

In particular, graphene is a carbon allotrope of a two-dimensional structure in which carbon atoms form a hexagonal honeycomb lattice structure by sp ² hybridization, and the thickness of single-layer graphene is 0.2 to 0.3 nm, which is the thickness of one carbon atom. Since graphene has high electrical conductivity and specific surface area, it is used in supercapacitors, sensors, batteries, electrodes (electrode active material) for actuators, touch panels, flexible displays, high-efficiency solar cells, heat dissipation films, coating materials, seawater desalination filters, and secondary batteries. It is used in various fields such as electrodes and ultra-fast chargers.

The use of these excellent properties of nano-carbon-based materials is currently being realized in molecular-level carbon nanotubes and graphene using chemical vapor deposition, etc., but in the bulk unit, large-area and mass synthesis and uniform nano-carbon crystal structure are realized Due to the difficulties of the situation, the excellent characteristics are not effectively expressed.

Recently, research is being conducted to expand the excellent physical properties of graphene in a bulk unit by enlarging and densifying mass-produced graphene oxide and carbon nanotubes through a connecting medium or van der Waals forces between graphene layers. Among these technologies, nano-carbon fiber spinning technology is in the limelight as a technology that can maximize electrical and thermal properties as well as mechanical properties of nano-carbon by maximizing the orientation and interaction of graphene layers. Herein, fiberization of nanocarbon can be generally realized by linearly aggregating nanocarbon by spinning in a coagulation bath capable of reducing the repulsive force between graphene layers of the nanocarbon dispersion.

For example, in the case of a conventional coagulation bath using only a coagulation solvent such as ethyl acetate, there is a problem in that the shrinkage rate and drying rate of fibers are very fast. Such a fast shrinkage rate forms a structural defect of the fiber, and a fast drying rate becomes a factor that makes it difficult to handle the fiber.

Republic of Korea Patent Publication No. 10-2014-0144900

The problem to be solved by the present invention is to provide an organic coagulation bath capable of controlling the shrinkage rate and drying rate of graphene fibers during spinning in the manufacture of graphene oxide fibers using wet spinning.

One aspect of the present invention in order to achieve the above object provides a graphene oxide fiber manufacturing method. The graphene oxide fiber manufacturing method includes preparing a graphene oxide dispersion containing a graphene oxide sheet and a dispersion medium, a coagulation solvent that pushes the dispersion medium, a crosslinking agent that forms a bridge between the graphene oxide sheets, and the Preparing graphene oxide gel fibers by spinning the dispersion in a coagulation bath containing a coagulation solvent and an emulsifier for mixing the crosslinking agent, and drying the graphene oxide gel fibers.

The dispersion medium may be a polar organic solvent. The coagulation solvent may be an amine-based solvent of secondary amine or tertiary amine. The coagulation solvent may be triethylamine, diethylamine or dipropylamine. The crosslinking agent may be a monovalent metal salt or an ammonium salt. The crosslinking agent may be ammonium thiocyanate.

The emulsifier may be acetonitrile. The coagulation solvent and the emulsifier may be contained in a volume ratio of 1:0.7 to 1:2.5 in the coagulation bath. The coagulation solvent and the crosslinking agent may be contained in a ratio of 1:0.005 to 1:0.23 (ml:g) in the coagulation bath. The coagulation solvent, emulsifier, and crosslinking agent in the coagulation bath may be contained in a ratio of 1:1:0.005 to 1:1:0.23 (ml:ml:g).

In order to achieve the above object, another aspect of the present invention provides a coagulation bath for graphene wet spinning. In spinning a graphene oxide dispersion including a graphene oxide sheet and a dispersion medium, the coagulation bath includes a coagulation solvent that pushes the dispersion medium, a crosslinking agent that forms a crosslink between the graphene oxide sheet, and the coagulation solvent and the crosslinking agent. It may contain an emulsifier for mixing. The coagulation bath may have a pH range of 10.10 to 10.55.

According to the present invention, in the manufacture of graphene oxide fibers using wet spinning, it is possible to provide an organic coagulation bath capable of controlling the shrinkage rate and drying rate of graphene oxide gel fibers during spinning. Accordingly, the prepared graphene oxide fibers may exhibit excellent structural stability and may be hybridized with various materials.

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

1 is a schematic diagram showing a graphene oxide fiber manufacturing process using a coagulation bath according to an embodiment of the present invention.
2 is a photograph of graphene oxide fibers prepared according to Preparation Examples 5 and 6 of the present invention.
3a and 3b are graphs showing the results of Experimental Example 2 of the present invention.

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

While the present invention is susceptible to various modifications and variations, specific embodiments thereof are shown by way of illustration in the drawings and will be described in detail below. However, it is not intended to limit the present invention to the particular form disclosed, but rather the present invention includes all modifications, equivalents and substitutions consistent with the spirit of the present invention as defined by the claims.

1 is a schematic diagram showing a graphene fiber manufacturing process using a coagulation bath according to an embodiment of the present invention.

Referring to FIG. 1 , a graphene oxide dispersion 100 may be prepared. The dispersion 100 may be a spinning solution for performing wet spinning. Specifically, the dispersion 100 may be a graphene oxide sheet dispersed in a dispersion medium.

The graphene oxide sheet is generally obtained by chemically exfoliating graphite, for example, unit graphenes having a thickness ranging from several nm to several tens of nm are stacked in several to several tens of layers. As such, an oxygen functional group such as a hydroxyl group (-OH), a carboxy group (-COOH), or a carbonyl group (-C=O) bonded to the edge portion and upper and lower portions of the graphene oxide sheet may be provided.

The dispersion medium may be an organic solvent, specifically, a polar organic solvent for evenly dispersing the graphene oxide sheet. Accordingly, the graphene oxide sheet, specifically, the oxygen functional group having polarity in the graphene oxide sheet may be better mixed with the dispersion medium. For example, the dispersion medium is dimethylformamide (DMF), dimethyl sulfoxide (DMSO), tetrahydrofuran (THF) or ethyl acetate (EA), or methanol, ethanol, ethylene It may be an alcohol such as glycol or n-butanol. For example, the dispersion medium may be dimethylformamide (DMF) or dimethyl sulfoxide (DMSO).

The concentration of the graphene oxide dispersion 100 is 1 mg/ml to 80 mg/ml, specifically, 1 mg/ml to 50 mg/ml, more specifically, 1 mg/ml to 10 mg/ml, more specifically, 5 mg/ml can

The dispersion 100, that is, the spinning solution may be spun into the coagulation bath 200 through the nozzle 101 to produce the graphene oxide gel fibers 30a. The coagulation bath 200 may contain a cross-linking agent, an emulsifier and a coagulation solvent.

The coagulation solvent may be filled between the graphene oxide sheets in which the dispersion medium was present by pushing the dispersion medium in the spinning solution. That is, the coagulation solvent may be used to accelerate the coagulation of the graphene oxide fiber by rapidly extracting the dispersion medium. For example, the coagulation solvent is an organic solvent, specifically, an amine solvent such as a secondary amine or a tertiary amine, a ketone solvent such as acetone, an acetate solvent such as ethyl acetate, or an alcohol solvent such as ethanol or propanol. can For example, the coagulation solvent may be an alkylamine having 1 to 3 carbon atoms, specifically, a dialkylamine or trialkylamine having 1 to 3 carbon atoms. For example, the coagulation solvent may be triethylamine, diethylamine or dipropylamine, and specifically, triethylamine.

The cross-linking agent may increase the strength of the graphene oxide gel fibers 30a by forming crosslinks between graphene oxide sheets during spinning. Accordingly, it is possible to compensate for a problem in which the strength of the graphene oxide fiber is weakened by using only a coagulation solvent such as, for example, ethyl acetate as a conventional coagulation bath. In addition, the contraction rate and drying rate of the graphene oxide gel fibers 30a may be controlled by adjusting the amount of the crosslinking agent compared to the coagulation solvent.

More specifically, at the same time as the coagulation solvent is filled between the graphene oxide sheets, at this time, the crosslinking agent forms a bridge between the graphene oxide sheets, thereby preventing the graphene oxide gel fibers 30a from rapidly shrinking, , the drying time of the gel fibers 30a can be delayed. Accordingly, it is possible to reduce the risk of occurrence of structural defects of graphene oxide fibers (not shown) to be formed later.

That is, the coagulation bath of the present invention includes a crosslinking agent that forms a crosslink between graphene oxide sheets, so that problems caused by fast shrinkage and drying speed, which occurred when only a coagulation solvent was used as a coagulation bath, do not occur. , can exert an effect of increasing the structural stability of the finally formed graphene oxide fiber.

The crosslinking agent is contained in a sufficient amount compared to the coagulation solvent in order to delay the shrinkage rate and drying rate of the graphene oxide fiber, but the content is too large to prevent the gel fiber from drying. You can have a composition ratio. For example, in the coagulation bath, the coagulation solvent and the crosslinking agent are 1:0.005 to 1:0.23 (ml:g), specifically 1:0.01 to 1:0.2 (ml:g), more specifically, 1: It may be contained in a ratio of 0.09 to 1:0.2 (ml:g) and more specifically 1:0.1 to 1:0.16 (ml:g).

The crosslinking agent may be in the form of a salt, a metal salt or a non-metal salt, and for example, a metal cation or a non-metal cation and an anion may be dissolved in water. The metal cation may be a monovalent metal cation, sodium ion (Na ⁺ ) or potassium ion (K ⁺ ), and the non-metal cation may be an ammonium ion (NH ₄ ⁺ ). The anion is nitrate ion (NO ₃ ^- ), chloride ion (Cl ^- ), sulfide ion (S ₂ ^- ), sulfate ion (SO ₄ ^2- ), carbonate ion (CO ₃ ^2- ) or thiocyanate ion (SCN ^- ). For example, the crosslinking agent may be ammonium thiocyanate (NH ₄ SCN) or sodium thiocyanate (NaSCN), and more specifically, the crosslinking agent may be ammonium thiocyanate (NH ₄ SCN).

The emulsifier is for mixing the coagulation solvent and the crosslinking agent in the coagulation bath 200, and may be an amphiphilic solvent having both hydrophobic and hydrophilic properties. Accordingly, the emulsifier can ensure that the crosslinking agent present in the form of a salt in water is well dissolved in the coagulation solvent, which is an organic solvent.

The emulsifier may exhibit Lewis base characteristics. That is, the emulsifier may be amphiphilic and show Lewis basicity at the same time. Accordingly, the coagulation bath itself may exhibit basicity without including a pH adjusting agent. Accordingly, it is possible to increase the attractive force between the negatively charged graphene oxide fiber and the positively charged crosslinking agent spun into the coagulation bath. The pH and characteristics of the coagulation bath will be described in detail later through experimental examples.

The type of the emulsifier is not particularly limited, but, for example, the emulsifier may be acetonitrile. In order for the emulsifier to maintain a gel state without phase separation of the graphene oxide gel fibers 30a, the coagulation solvent and the emulsifier in the coagulation bath 200 have a ratio of 1:0.7 to 1:2.5, specifically, 1 : 0.7 to 1:2, specifically, 1:1 to 1:2, for example, may be contained in a volume ratio of 1:1.

The coagulation bath may exhibit basicity. This may be due to the emulsifier in the coagulation bath. Accordingly, the attractive force between the negatively charged graphene oxide fiber and the positively charged crosslinking agent radiated into the coagulation bath may be increased.

More specifically, the graphene oxide fiber, which is negatively charged by the oxygen functional group, changes its characteristics according to the pH environment. For example, the negative charge characteristics are weakened in an acidic environment and the negative charge characteristics are strengthened in a basic environment. Therefore, when the spinning solution is spun into the coagulation bath showing basicity, the difference between the positive charge of the crosslinking agent and the negative charge of the graphene oxide fiber is increased, thereby exhibiting an effect of increasing the graphene oxide fiber. The attractive force between the oxide fiber and the crosslinking agent is further increased. Accordingly, an effect of further improving the structural stability of the formed graphene oxide gel fibers 30a may be exhibited.

For example, the coagulation bath 200 has a pH of 10 or more, specifically, pH 10.10 to 10.55, more specifically, pH 10.36 to 10.46, more specifically, pH 10.37 to 10.45, more specifically, pH 10.38 to 10.44 days can The pH range of the coagulation bath 200 increases the attractive force of the graphene oxide fibers and the crosslinking agent, thereby improving the structural stability of the formed gel fibers 30a.

The pH of the coagulation bath 200 may be adjusted according to the composition ratio of the coagulation solvent, the crosslinking agent, and the emulsifier. For example, in order for the coagulation bath 200 to exhibit a pH range, the coagulation solvent and the emulsifier in the coagulation bath 200 are 1:0.7 to 1:2.5, specifically, 1:0.7 to 1:2 , Specifically, it may be contained in a volume ratio of 1:1 to 1:2, for example, 1:1. For example, the coagulation solvent, emulsifier and crosslinking agent in the coagulation bath 200 are 1:1:0.005 to 1:1:0.23 (ml:ml:g), specifically 1:1:0.01 to 1:1: 0.2 (ml:ml:g), more specifically 1:1:0.09 to 1:1:0.2 (ml:ml:g) more specifically 1:1:0.1 to 1:1:0.16 (ml:ml: g) may be mixed.

The graphene oxide gel fibers 30a may be dried at room temperature in an air atmosphere, for example. Accordingly, a graphene oxide fiber having a structure in which a plurality of graphene oxide sheets are stacked in the thickness direction, and the stacked graphene oxide sheets are aligned in the length direction of the fiber to shrink the inside of the sheet surface can be manufactured. can The graphene oxide fiber may exhibit structural stability between internal graphene oxide sheets while improving mechanical strength compared to conventional graphene oxide fibers.

The dried graphene oxide fibers may be heat treated. The heat treatment may reduce graphene oxide in the graphene oxide fiber, and thus, a reduced graphene oxide fiber having excellent structural stability may be prepared. At this time, the coagulation bath 200 can be almost entirely removed by the heat treatment, but in some cases, the coagulation bath 200, that is, the crosslinking agent, emulsifier and coagulation solvent inside the reduced graphene oxide fiber It may contain small amounts. Since the coagulation solvent is highly volatile, the remaining amount of the crosslinking agent and the emulsifier may be extremely small. The heat treatment may be performed at a temperature of 800° C. to 1300° C., for example, 1200° C., in an inert gas atmosphere such as argon gas.

In other words, the graphene oxide fiber manufacturing method according to an embodiment of the present invention has the effect of simultaneously improving the strength and structural stability of the graphene oxide fiber formed by adjusting the components and their component ratios in the coagulation bath. exert

That is, unlike conventional coagulation baths that use only coagulation solvents, the coagulation bath of the present invention includes a crosslinking agent capable of forming crosslinks between graphene oxide sheets and a coagulation solvent that is an amine-based solvent for rapid extraction of the dispersion medium of the spinning solution. , An emulsifier for mixing the crosslinking agent and the coagulation solvent may be included. Accordingly, the shrinkage rate and drying rate of the graphene oxide gel fibers can be controlled.

In addition, the present invention, in order to be able to delay the drying rate and shrinkage rate of the graphene oxide gel fiber and reduce the shrinkage rate of the gel fiber, specifically, the shrinkage rate in the thickness direction of the gel fiber, the coagulation Solvent and crosslinker are 1:0.005 to 1:0.23 (ml:g), specifically 1:0.01 to 1:0.20 (ml:g), more specifically, 1:0.09 to 1:0.2 (ml:g) more specifically It may be contained in a ratio of 1:0.1 to 1:0.16 (ml:g). In addition, in order for the gel fiber to exhibit excellent coagulation characteristics without phase separation and to enable smooth spinning, the coagulation solvent and the emulsifier are 1:0.7 to 1:2.5, specifically, 1:0.7 to 1:2, specifically , 1:1 to 1:2, for example, may be contained in a volume ratio of 1:1.

In addition, the coagulation bath 200 has a range of pH 10 or more, specifically, pH 10.10 to 10.55, more specifically, pH 10.36 to 10.46, more specifically, pH 10.37 to 10.45, more specifically, pH 10.38 to 10.44. To show, in the coagulation bath 200, the coagulation solvent and the emulsifier may be mixed in a volume ratio of 1:0.7 to 1:2.5, specifically, 1:1 to 1:2. For example, the coagulation solvent, crosslinking agent and emulsifier in the coagulation bath 200 are 1:1:0.005 to 1:1:0.23 (ml:ml:g), specifically 1:1:0.01 to 1:1: 0.2 (ml:ml:g), more specifically 1:1:0.09 to 1:1:0.2 (ml:ml:g) more specifically 1:1:0.1 to 1:1:0.16 (ml:ml: g) may be mixed.

Hereinafter, in order to explain the present invention in more detail, preferred experimental examples according to the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms.

<Preparation Example: Graphene Oxide Fiber Preparation>

After obtaining graphene oxide powder from graphite powder, a graphene oxide dispersion was prepared by dispersing the graphene oxide powder in DMF at a concentration of 5 mg/ml. The dispersion was spun into a coagulation bath in which 5 ml of triethyl amine, 5 ml of acetonitrile, and 0.8 g of ammonium thiocyanate were mixed to prepare a graphene oxide gel fiber. Then, the gel fibers were dried at room temperature (25° C.).

<Experimental Example 1: Strength comparison of graphene oxide fibers (according to the composition ratio of coagulation solvent: crosslinking agent: emulsifier)>

Graphene oxide gel fibers were prepared in the same manner as in the above-described preparation example, but using a coagulation bath having different ratios of triethylamine as a coagulation solvent, ammonium thiocyanate as a crosslinking agent, and acetonitrile as an emulsifier. After manufacturing, the strength of the gel fibers was measured and compared.

<Experimental Example 2: Comparison of pH value measurement of coagulation bath (according to composition ratio of coagulation solvent: crosslinking agent: emulsifier)>

Coagulation baths were prepared as in the above-described preparation example, but the pH values of the coagulation baths of the experimental group were measured in different ratios of triethylamine as a coagulation solvent, ammonium thiocyanate as a crosslinking agent, and acetonitrile as an emulsifier.

For experimental group 1, the volume ratio of triethylamine and acetonitrile was 1:0 (Comparative Example 1), 1:0.5 (Production Example 1), 1:1 (Production Example 3), 1:2 (Production Example 8), 1 :3 (Preparation Example 10), 1:4 (Preparation Example 11) The pH of the different coagulation baths was measured. At this time, for accurate comparison, ammonium cyanate was fixed to have a ratio of 0.01, except for Comparative Example 1.

Meanwhile, in experimental group 2, the ratio of triethylamine:acetonitrile:ammonium thiocyanate was 1:1:0 (ml:ml:g) (Comparative Example 2), 1:1:0.01 (ml:ml:g) (Preparation Example 3), 1:1:0.08 (ml:ml:g) (Preparation Example 4), 1:1:0.1 (ml:ml:g) (Preparation Example 5), 1:1:0.16 (ml: ml:g) (Preparation Example 6), 1:1:0.24 (ml:ml:g) (Preparation Example 7), and the pH of the coagulation bath was measured.

Specific experimental examples (1, 2) and the results are summarized in Table 1 below, and will be described in detail in Table 1, FIGS. 2 and 3 to be described later.

<Table 1>

Referring to Table 1, in the case of the conventional coagulation bath of Comparative Example 1, the drying speed of the gel fiber was high, so internal structural defects were expected, and the strength of the fiber was also confirmed to be very weak.

As in Preparation Examples 1 and 2, when acetonitrile as an emulsifier is contained less than triethylamine as a coagulation solvent (ex. 1:0.5 or less), it is difficult to mix with ammonium thiocyanate as a crosslinking agent in the coagulation bath, resulting in the formation of gel fibers. Phase separation occurred, and when a lot of acetonitrile was contained compared to triethylamine (ex. 1:3 or more) as in Preparation Examples 10 to 11, the emulsifier content was too high, and the coagulability of the fiber was weakened independently of the strength of the fiber, so it was not suitable for spinning. Disadvantages are to be expected.

On the other hand, when triethylamine and acetonitrile in Preparation Examples 8 and 9 have a component ratio of 1:2, the coagulation force to the extent that spinning of the fiber is possible, but the drying rate and shrinkage rate (in the thickness direction) of the fiber In terms of , it did not exert any particular effect. However, the fact that the strength of Preparation Example 9 is improved compared to Preparation Example 8 is interpreted as due to the effect of the crosslinking agent.

Referring to Preparation Examples 3 to 7, when triethylamine and acetonitrile have a component ratio of 1: 1 (except for Comparative Example 2, which does not contain a crosslinking agent), spinning was generally performed smoothly. At this time, it was confirmed that the strength of the fiber gradually increased as the content of the crosslinking agent increased. Among them, in the case of Preparation Examples 4 to 6, the effect of reducing the drying rate and shrinkage (in the thickness direction) during the formation of gel fibers was exhibited. However, in the case of Preparation Example 7, the content of the crosslinking agent was too high, and the drying rate of the fibers was too slow.

That is, as in the embodiment of the present invention, the coagulation bath of the present invention is when the coagulation solvent: emulsifier is mixed in a component ratio of 1: 1, more specifically, the coagulation solvent: emulsifier: crosslinking agent is 1: 1: 0.01 to 1: 1: 0.16, more specifically, when contained in a component ratio of 1: 1: 0.1 to 1: 1: 0.16, the drying rate and shrinkage rate of the gel fibers are delayed, and the shrinkage rate in the thickness direction of the gel fibers is increased. The reduction effect can be maximized. Accordingly, it is possible to reduce the risk of occurrence of structural defects in the fiber and to exhibit excellent strength characteristics of the fiber.

2 is a photograph of graphene oxide fibers prepared according to Preparation Examples 5 and 6 of the present invention.

Referring to FIG. 2, it was confirmed that the graphene oxide fibers of the present invention were spun more uniformly and stably in the coagulation bath, and the spun fibers exhibited high strength characteristics sufficient to enable continuous spinning.

3a and 3b are graphs showing the results of Experimental Example 2 of the present invention.

Referring to Figure 3a, as a result of measuring the pH according to the volume ratio of triethylamine as a coagulation solvent and acetonitrile as an emulsifier, the remaining 1:0.5 (Preparation Example 1) and 1:1 (Preparation Example 3) except for Comparative Example 1 , 1:2 (Preparation Example 8), 1:3 (Preparation Example 10), and 1:4 (Preparation Example 11) all show a pH value of 10 or more, the pH of the coagulation bath is affected by the content of the emulsifier interpreted as Among them, it was confirmed that spinning was performed smoothly when the volume ratio of triethylamine and acetonitrile was 1:1 to 1:2.

Referring to Figure 3b, except for Comparative Example 2, the component ratio of triethylamine: acetonitrile: ammonium thiocyanate was 1: 1: 0.01 (Preparation Example 3), 1: 1: 0.08 (Preparation Example 4), 1: In the case of 1:0.1 (Production Example 5), 1:1:0.16 (Production Example 6), and 1:1:0.24 (Production Example 7), the pH value was 10.36 to 10.48. However, 1: 1: 0.24 (Preparation Example 7) had a problem in that the fibers were not dried.

1:1:0.01 (Production Example 3), 1:1:0.08 (Production Example 4), 1:1:0.1 (Production Example 5), and 1:1:0.16 (Production Example 6) all perform spinning smoothly. and showed the effect of slowing down the drying rate of gel fibers. Among them, in the case of 1: 1: 0.1 (Production Example 5) and 1: 1: 0.16 (Production Example 6), not only the drying speed of the gel fiber but also the effect of reducing the shrinkage in the thickness direction was exhibited.

In addition, through Experimental Example 2, the coagulation bath of the present invention exhibits an effect of delaying the shrinkage rate and drying rate of graphene oxide gel fibers during spinning, and the component ratio of the components in the coagulation bath, that is, the coagulation solvent, the crosslinking agent and the emulsifier Accordingly, it can be seen that the pH of the coagulation bath can be adjusted. For example, when the composition ratio of the coagulation solvent:crosslinking agent:emulsifier is 1:1:0.10 to 1:1:0.16, the pH of the coagulation bath has a range of 10.38 to 10.44, thereby reducing the shrinkage rate of the graphene oxide gel fibers. And the effect of delaying the drying rate and the effect of increasing the structural stability of the graphene oxide gel fibers can be exhibited.

On the other hand, the embodiments of the present invention disclosed in this specification and drawings are only presented as specific examples to aid understanding, and are not intended to limit the scope of the present invention. It is obvious to those skilled in the art that other modified examples based on the technical idea of the present invention can be implemented in addition to the embodiments disclosed herein.

100: graphene oxide dispersion 101: nozzle
200: coagulation bath 30a: graphene oxide gel fiber

Claims (12)

Preparing a graphene oxide dispersion containing a graphene oxide sheet and a dispersion medium;
In a coagulation bath containing a coagulation solvent that pushes the dispersion medium, a crosslinking agent that forms a crosslink between the graphene oxide sheets, and an emulsifier that mixes the coagulation solvent and the crosslinking agent, the dispersion is spun to form graphene oxide gel fibers. manufacturing; and
A method for producing a graphene oxide fiber comprising drying the graphene oxide gel fiber. According to claim 1,
The dispersion medium is a polar organic solvent, graphene oxide fiber manufacturing method. According to claim 1,
The coagulation solvent is an amine-based solvent of secondary amine or tertiary amine, graphene oxide fiber manufacturing method. According to claim 3,
The coagulation solvent is a graphene oxide fiber manufacturing method of triethylamine, diethylamine or dipropylamine. According to claim 1,
The crosslinking agent is a monovalent metal salt or ammonium salt, graphene oxide fiber manufacturing method. According to claim 5,
The crosslinking agent is ammonium thiocyanate, graphene oxide fiber manufacturing method. According to claim 1,
The emulsifier is acetonitrile (acetonitrile), graphene oxide fiber manufacturing method. According to claim 1,
In the coagulation bath, the coagulation solvent and the emulsifier are contained in a volume ratio of 1:0.7 to 1:2.5, graphene oxide fiber manufacturing method. According to claim 1,
In the coagulation bath, the coagulation solvent and the crosslinking agent are contained in a ratio of 1: 0.005 to 1: 0.23 (ml: g), graphene oxide fiber manufacturing method. According to claim 1,
In the coagulation bath, the coagulation solvent, emulsifier and crosslinking agent are contained in a ratio of 1: 1: 0.005 to 1: 1: 0.23 (ml: ml: g), graphene oxide fiber manufacturing method. In spinning a graphene oxide dispersion containing a graphene oxide sheet and a dispersion medium,
a coagulation solvent that pushes the dispersion medium, and a crosslinking agent that forms a bridge between the graphene oxide sheets; A coagulation bath for graphene wet spinning comprising an emulsifier for mixing the coagulation solvent and the crosslinking agent. According to claim 11,
The coagulation bath has a pH range of 10.10 to 10.55, graphene wet spinning coagulation bath.

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