WO2018182111A1 - Carbon nanotube dispersion solution and preparation method therefor - Google Patents

Abstract

The present invention relates to a carbon nanotube dispersion solution and a preparation method therefor. The carbon nanotube dispersion solution of the present invention comprises a carbon nanotube, a surfactant, a polyvinyl butyral, and a solvent and, particularly, further comprises clay, and can have excellent dispersibility, dispersion stability, and adhesive strength according to the use of a polyvinyl butyral having a degree of polymerization of 300-1,000 while using, as the carbon nanotube, a mixture of a carbon nanotube having a diameter of 1-4 nm and a carbon nanotube having a diameter of 5-8 nm in a weight ratio of 1:0.2-1. In addition, the method for preparing the carbon nanotube dispersion solution, of the present invention, comprises: a first step of preparing a mixture by mixing a carbon nanotube, a surfactant, a polyvinyl butyral, and a solvent; and a second step of sonicating the mixture, and thus a carbon nanotube dispersion solution having excellent dispersibility, dispersion stability, and adhesive strength can be prepared.

Description

Carbon nanotube dispersion and its manufacturing method

The present invention relates to a carbon nanotube dispersion and a preparation method thereof.

The present invention is the result of the research carried out in support of the "Small and Medium Business Technology Innovation Development" of the Small and Medium Business Administration and Technology Information Agency (task unique number: 1425104887, detailed task number: S2312152). In addition, the present invention is the result of research conducted by the Ministry of Trade, Industry and Energy and the Gangwon Regional Project Evaluation Team to support "Regional flagship development project (non-R & D)" (task unique number: R0005121).

Carbon nanotubes are small molecules of 1 nanometer in diameter, in which carbons connected by hexagonal rings form a long shape, and have excellent electrical properties such as conductivity, reflectance, conductivity, and physical properties such as adhesion, durability, abrasion resistance, and bendability. And linear conductivity. Accordingly, the utilization of such materials as flat panel display devices, highly integrated memory devices, secondary batteries, ultracapacitors, hydrogen storage materials, electrochemical sensors, electromagnetic shielding, wires (cables), and the like is increasing.

In general, carbon nanotubes may be applied by preparing a carbon nanotube dispersion in which carbon nanotubes are uniformly dispersed in a solvent or a polymer, and coating or spraying the same on an electrochemical device or component to form a carbon nanotube (film) layer. . However, carbon nanotubes are composed of only a few dozen carbon atoms in the circumference of several micrometers in length and have a very high aspect ratio, and due to attraction between carbon nanotubes, agglomeration occurs and dispersibility and dispersion stability. This is a low problem. As a result, it is difficult to prepare a carbon nanotube dispersion in which carbon nanotubes are uniformly dispersed in a solvent or a polymer, and cannot form a carbon nanotube (film) layer in which carbon nanotubes are uniformly dispersed. There was a problem that the characteristics were not sufficiently improved.

In order to solve this problem, various methods for improving the dispersibility and dispersion stability of carbon nanotubes have been attempted, and in Korean Patent Laid-Open No. 10-2013-0053015, a super-rope carbon nanotube bundle ( Bundle) is prepared by dry milling, wet milling and mixing with a solvent to provide a carbon nanotube dispersion having a high concentration and high dispersion characteristics, but a separate device for dry milling and wet milling the carbon nanotubes; There is a problem that the equipment is required, there is a problem that the dispersion of the carbon nanotube bundle is not complete, so that the dispersibility and dispersion stability improvement effect is insignificant.

In addition, the Republic of Korea Patent Publication No. 10-2012-0021807 surface-treated carbon nanotubes, the surface of the carbon nanotubes surface-treated to include 0.1 to 10% by weight of functional groups including oxygen, nitrogen and sulfur or mixtures thereof The present invention provides a high concentration of carbon nanotube dispersion with improved dispersibility and dispersion stability. However, as the surface modification of the carbon nanotube is required, the cost is increased and the effect of improving dispersibility and dispersion stability is insignificant. There was a problem. In addition, the above patents only consider the improvement of the powder property of the carbon nanotube dispersion, but do not consider the improvement of the adhesion of the carbon nanotube dispersion, so that the dispersibility, dispersion stability and adhesion of the carbon nanotube dispersion are simultaneously There is a need for development of techniques that can be improved.

It is a first object of the present invention to provide a carbon nanotube dispersion in which dispersibility, dispersion stability and adhesion are simultaneously improved by including carbon nanotube, a surfactant, polyvinyl butyral and a solvent.

The second object of the present invention is carbon nanotubes. A first step of preparing a mixture by mixing a surfactant, polyvinyl butyral and a solvent, and a second step of sonicating the mixture, thereby improving carbon dispersibility and dispersion stability and adhesion at the same time. The present invention provides a method for preparing a nanotube dispersion.

The object of the present invention is not limited to the technical problem as described above, another technical problem can be derived from the following description.

The present invention to achieve the first object carbon nanotubes. A carbon nanotube dispersion comprising a surfactant, polyvinyl butyral and a solvent is provided.

The carbon nanotube dispersion is 1 to 8% by weight of the carbon nanotubes, 1 to 5% by weight of the surfactant, 3 to 25% by weight of the polyvinyl butyral and the solvent 65 to 90 based on the total weight of the carbon nanotube dispersion It may include weight percent.

The carbon nanotube dispersion may further include nano clays.

The carbon nanotube dispersion may include 0.01 to 0.1 wt% of the nano clay based on the total weight of the carbon nanotube dispersion.

The carbon nanotubes may have a particle diameter of 8 nanometers or less.

The carbon nanotubes may be mixed with a carbon nanotube having a particle size of 1 to 4 nanometers and carbon nanotubes having a particle size of 5 to 8 nanometers in a weight ratio of 1: 0.2 to 1.

The average degree of polymerization of the polyvinyl butyral may be 300 to 700.

The surfactant may be at least one selected from the group consisting of sodium dodecyl sulfate, sodium cholate hydrate, and sodium dodecyl benzene sulfonate.

The solvent is water, acetone, dimethyl sulfoxide, dimethylformamide, dimethylformamid, benzene, toluene, xylene, chloroform, pyridine, pyridine. It may include any one or more selected from the group consisting of, tetrahydrofuran (Tetrahydrofuran), methyl ethyl ketone, N-methyl-2-piperidone (N-Methyl-2-pyrrolidone).

The present invention is carbon nanotubes to achieve the second object. A first step of preparing a mixture by mixing a surfactant, polyvinyl butyral and a solvent; And it provides a method for producing a carbon nanotube dispersion comprising a second step of sonicating the mixture.

The carbon nanotube dispersion is 1 to 8% by weight of the carbon nanotubes, 1 to 5% by weight of the surfactant, 3 to 25% by weight of the polyvinyl butyral and the solvent 65 to 90 based on the total weight of the carbon nanotube dispersion It may include weight percent.

In the first step may further comprise a nanoclay.

The carbon nanotube dispersion may include 0.01 to 0.1 wt% of the nano clay based on the total weight of the carbon nanotube dispersion.

The carbon nanotubes may have a particle diameter of 8 nanometers or less.

The carbon nanotubes may be a mixture of carbon nanotubes having a particle diameter of 1 to 4 nanometers and carbon nanotubes having a particle diameter of 5 to 8 nanometers in a weight ratio of 1: 0.2 to 1.

The average degree of polymerization of the polyvinyl butyral may be 300 to 700.

The carbon nanotube dispersion of the present invention includes carbon nanotubes, a surfactant, polyvinyl butyral and a solvent, so that dispersibility, dispersion stability, and adhesion can be simultaneously improved.

Carbon nanotube dispersion method of the present invention is a carbon nanotube. A first step of preparing a mixture by mixing a surfactant, polyvinyl butyral and a solvent, and a second step of sonicating the mixture, thereby improving carbon dispersibility and dispersion stability and adhesion at the same time. Nanotube dispersions can be provided.

1 shows the measured UV absorbance of Example 1, Example 2, Comparative Example 1 and Comparative Example 2 of the present invention.

2 is a view showing a state immediately after the preparation of the carbon nanotube dispersion prepared according to Example 2, Example 4, Comparative Example 11 and Comparative Example 12 and after 48 hours.

3 is a view showing a state immediately after the preparation of the carbon nanotube dispersion liquid of Examples 1 and 2, 1 hour after the preparation, 6 hours after, 12 hours after the preparation.

4 is a view showing a state immediately after preparation of the carbon nanotube dispersion liquids of Comparative Examples 1, 2 and 16, 1 hour after preparation, 6 hours later, and 12 hours later.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention.

The terms or words used in the specification and claims of the present invention are not to be construed in a conventional or dictionary sense, and the inventors may appropriately define the concept of terms in order to best explain their invention in the best way. Based on the principle, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention.

Throughout the specification of the present invention, when a part is said to "include" a certain component, it means that it can further include other components, without excluding the other components unless otherwise stated. .

In the specification of the present invention, "A and / or B" means A or B, or A and B.

Hereinafter, the present invention has been described in detail with reference to the accompanying drawings, but the present invention is not limited thereto.

The present invention provides a carbon nanotube dispersion.

Carbon nanotube dispersion according to an embodiment of the present invention is carbon nanotubes. It includes a surfactant, polyvinyl butyral and a solvent, thereby improving the dispersibility, dispersion stability and adhesion at the same time can provide a carbon nanotube dispersion having excellent dispersibility, dispersion stability and adhesion . In particular, the carbon nanotube dispersion of the present embodiment is carbon nanotubes. Further comprising clay in a surfactant, polyvinyl butyral and a solvent, carbon nanotubes having a particle diameter of 1 to 4 nanometers and carbon nanotubes having a particle diameter of 5 to 8 nanometers are 1: As the polymerization degree of polyvinyl butyral is 300 to 1000 while using a mixture of 0.2 to 1 by weight, dispersibility, dispersion stability, and adhesion may be further improved.

According to an embodiment of the present invention, the carbon nanotubes may have a particle diameter of 8 nanometers or less, and when the particle diameter of the carbon nanotubes exceeds 8 nanometers, the weight of the carbon nanotubes increases as well as the carbon nanotube particles. There may be a problem that the cohesive force between them is reduced so that the dispersibility and dispersion stability of the carbon nanotube dispersion.

Particularly, in the present embodiment, carbon nanotubes having a particle diameter of 8 nanometers or less may be used, and carbon nanotubes having a particle size of 1 to 4 nanometers and carbon nanotubes having a particle size of 5 to 8 nanometers may be mixed. As described above, when carbon nanotubes having different particle diameters are mixed and used, not only the aggregation between the carbon nanotube particles is reduced, but the carbon nanotubes having a relatively light particle diameter of 1 to 4 nanometers in the dispersion even after a certain time. Is positioned at the top and the carbon nanotubes having a relatively heavy particle diameter of 5 to 8 nanometers are positioned at the bottom to maintain a uniformly dispersed state.

The carbon nanotubes having a particle diameter of 1 to 4 nanometers and the carbon nanotubes having a particle diameter of 5 to 8 nanometers may be mixed in a weight ratio of 1: 0.2 to 1, preferably in a weight ratio of 1: 0.3 to 0.8, more Preferably it may be mixed in a weight ratio of 1: 0.5 to 0.6.

If the weight ratio of the carbon nanotubes having a particle diameter of 5 to 8 nanometers is less than 0.2 with respect to the carbon nanotubes having a particle diameter of 1 to 4 nanometers, the carbon nanotube particles may be aggregated to reduce dispersibility and dispersion stability. When the weight ratio of the carbon nanotubes having a particle diameter of 5 to 8 nanometers is greater than 1, the carbon nanotubes that sink to the lower part of the dispersion are increased. Dispersibility and dispersion stability of the carbon nanotube dispersion may be lowered.

The carbon nanotube dispersion of the present embodiment may include 1 to 8% by weight, preferably 1 to 6% by weight, more preferably 2 to 5% by weight of the carbon nanotubes based on the total weight of the carbon nanotube dispersions. If the carbon nanotube dispersion contains less than 1 wt% of carbon nanotubes based on the total weight of the carbon nanotube dispersion, even if the carbon nanotube dispersion is applied to an electrochemical device or a component, the carbon nanotube dispersion does not exhibit electrical characteristics, and thus it may be meaningless. If the carbon nanotubes contain more than 8% by weight based on the total weight of the nanotube dispersion, there may be a problem in that the carbon nanotubes that do not disperse in the solvent and sink.

In this embodiment, the surfactant may include any one or more selected from the group consisting of sodium dodecyl sulfate, sodium cholate hydrate, and sodium dodecyl benzene sulfonate. have. In particular, in the present embodiment, by using sodium dodecyl sulfate as the surfactant, it is possible to further improve the dispersibility, dispersion stability and adhesion of the carbon nanotube dispersion.

The carbon nanotube dispersion of the present embodiment may include 1 to 5% by weight, preferably 1 to 4% by weight, more preferably 1.5 to 3% by weight of the surfactant based on the total weight of the carbon nanotube dispersion. If the carbon nanotube dispersion contains less than 1 wt% of surfactant based on the total weight of the carbon nanotube dispersion, not only the effect of improving the dispersibility, dispersion stability and adhesion of the carbon nanotube dispersion is generated but also agglomeration between the carbon nanotube particles occurs. There may be a problem that, if the surfactant contains more than 5% by weight based on the total weight of the carbon nanotube dispersion, there may be a problem that the electrostatic properties of the carbon nanotube is reduced.

Polyvinyl butyral, also called polyvinyl butyral, is a resin synthesized by reacting polyvinyl alcohol with butyl aldehyde under an acid catalyst. In the present embodiment, a polyvinyl butyral polymerization degree of 300 to 700 and a butylation degree of about 60 to 65 mol% may be used. If the degree of polymerization of the polyvinyl butyral is less than 300, there may be a problem that the adhesion of the carbon nanotube dispersion is lowered. If the degree of polymerization exceeds 700, the adhesion is improved but the dispersibility and dispersion stability are deteriorated. There may be.

Carbon nanotube dispersion of the present embodiment may include 3 to 25% by weight of the polyvinyl butyral based on the total weight of the carbon nanotube dispersion, preferably 4 to 20% by weight, more preferably 6 to 18% by weight May contain%. If the carbon nanotube dispersion contains less than 3% by weight of polyvinyl butyral based on the total weight of the carbon nanotube dispersion, the adhesion improvement effect may be insignificant, and the polyvinyl butyral based on the total weight of the carbon nanotube dispersion may be used. When it contains more than 25% by weight, the viscosity of the carbon nanotube dispersion becomes high, making it difficult to disperse or apply the carbon nanotube dispersion to the electrochemical device or component, and the viscosity of the polyvinyl butyral causes the carbon nanotube particles to clump. There may be a problem forming.

On the other hand, the carbon nanotube dispersion of the present embodiment as described above may further comprise a nano (clay), preferably may be a nano clay having a particle diameter of 1 to 100 nanometers. The nanoclays of this embodiment may be natural clays, synthetic clays, and mixtures thereof, and for example, laponite, montmorillonite, hectorite, saponite, and baydelite ( Beidellite), nontronite (Nontronite) and the like, but is not limited thereto.

As the nanoclay has an antistatic performance, it is possible to prevent the attraction of the carbon nanotube particles to aggregate by preventing the charging of the carbon nanotubes in the carbon nanotube dispersion of the present embodiment. However, since the nanoclay is viscous in the wet state, it can be entangled with carbon nanotubes to form agglomerates, and it is preferable to use a small amount because the nanoclay can be adsorbed with carbon nanotubes to form agglomerates.

The carbon nanotube dispersion of the present embodiment may include 0.01 to 0.1% by weight, preferably 0.02 to 0.08% by weight, more preferably 0.03 to 0.05% by weight, based on the total weight of the carbon nanotube dispersion. If the carbon nanotube dispersion contains less than 0.01% by weight of nanoclays based on the total weight of the carbon nanotube dispersion, the antistatic effect of the carbon nanotube may be low, and thus the effect of improving the dispersibility and dispersion stability of the carbon nanotube dispersion may be insignificant. If the nanodispersion is contained in an amount of more than 0.1% by weight based on the total weight of the tube dispersion, carbon nanotubes and nanoclays may be entangled to form lumps, thereby forming a precipitate, which may cause a problem in that dispersibility and dispersion stability are deteriorated. have.

The solvent is water, acetone, dimethyl sulfoxide, dimethylformamide, benzene, benzene, toluene, xylene, chloroform, pyridine, pyridine, Tetrahydrofuran (Tetrahydrofuran), methyl ethyl ketone (methyl ethyl ketone), N-methyl-2- piperidone (N-Methyl-2-pyrrolidone), including but not limited to any one or more selected from the group consisting of carbon Anything that can be applied to the preparation of the nanotube dispersion can be used without limitation.

Carbon nanotube dispersion of the present embodiment may include 65 to 90% by weight, preferably 70 to 90% by weight, more preferably 75 to 90% by weight of the solvent based on the total weight of the carbon nanotube dispersion. If the solvent contains less than 65% by weight of the carbon nanotube dispersion, the viscosity of the carbon nanotube dispersion is increased, so that the usability decreases and a space (solvent) in which the carbon nanotube is uniformly dispersed. There may be a problem that the dispersibility and dispersion stability is not enough due to insufficient, and when the solvent contains more than 90% by weight based on the total weight of the carbon nanotube dispersion, the concentration of carbon nanotubes in the carbon nanotube dispersion is low Chemical properties may be lowered.

Carbon nanotube dispersion according to an embodiment of the present invention as described above is an antistatic material, electrostatic dispersion material, conductive material, electromagnetic shielding material, electromagnetic wave absorber, RF (Radio frequency) absorber, solar cell material, fuel material for electrode material , Electronic device material, semiconductor device material, optoelectronic device material, notebook component material, computer component material, mobile phone component material, PDA component material, PSP component material, game machine component material, housing material, transparent electrode material, opaque electrode material, electric field Emission display material, BLU (back light unit) material, liquid crystal display material, plasma display panel material, light emitting diode material, touch panel material, electronic board material, billboard material, display material, heating element, radiator, plating material, catalyst, bath Catalyst, oxidizing agent, reducing agent, automobile parts material, ship parts material, aircraft parts material, protective tape material, adhesive material, tray Materials, Clean Room Materials, Transportation Equipment Parts Materials, Flame Retardant Materials, Antibacterial Materials, Metal Composites, Non-Ferrous Metal Composites, Medical Device Materials, Building Materials, Flooring Materials, Wallpaper Materials, Light Source Components Materials, Lamp Materials, Optical Equipment Components Materials, textile manufacturing materials, clothing manufacturing materials, electrical products materials, electronics manufacturing materials, secondary battery cathode active materials, secondary battery anode active materials, secondary battery materials, fuel cell materials, solar cell materials, memory devices and capacitors (P-ED) <C) may be used as a material, but is not limited thereto.

The present invention provides a method for producing a carbon nanotube dispersion.

Carbon nanotube dispersion method according to an embodiment of the present invention is carbon nanotubes. A first step of preparing a mixture by mixing a surfactant, polyvinyl butyral and a solvent, and a second step of sonicating the mixture, wherein the carbon nanotube dispersion prepared is dispersible and dispersed Stability and adhesion can be excellent. In particular, the present embodiment further comprises a clay in the carbon nanotubes, the surfactant, polyvinyl butyral and the solvent, the carbon nanotubes having a particle diameter of 1 to 4 nanometers and the particle diameter of 5 to 8 nanometers Dispersibility and dispersion stability and adhesion can be further improved by using a mixture of carbon nanotubes in a weight ratio of 1: 0.2 to 1 while using a polymerization degree of polyvinyl butyral of 300 to 1000.

(1) In the first step, carbon nanotubes. A mixture is prepared by mixing a surfactant, polyvinyl butyral and a solvent.

In the first step of the present embodiment, a mixture is prepared by mixing the carbon nanotubes, the surfactant, the polyvinyl butyral, and the solvent, wherein the nano clay may be further mixed with the mixture. In the first step, the carbon nanotube dispersion is based on the total weight of the carbon nanotubes 1 to 8% by weight, surfactant 1 to 5% by weight, polyvinyl butyral 3 to 25% by weight, solvent 65 to 90% by weight and nano It may include 0.01 to 0.1% by weight of clay, the material constituting the mixture with the carbon nanotube dispersion in the first step of the present embodiment and their weight ratio (wt%) is the same.

In addition, in the first step, agitation may be performed for uniform mixing of carbon nanotubes, a surfactant, polyvinylurethane, a solvent, and clay, and a stirring speed may be 200 to 500 rpm, but is not limited thereto.

According to an embodiment of the present invention, the carbon nanotubes may have a particle diameter of 8 nanometers or less, and when the particle diameter of the carbon nanotubes exceeds 8 nanometers, the weight of the carbon nanotubes increases as well as the carbon nanotube particles. There may be a problem that the cohesive force between them is reduced so that the dispersibility and dispersion stability of the carbon nanotube dispersion.

Particularly, in the present embodiment, carbon nanotubes having a particle diameter of 8 nanometers or less may be used, and carbon nanotubes having a particle size of 1 to 4 nanometers and carbon nanotubes having a particle size of 5 to 8 nanometers may be mixed. As described above, when carbon nanotubes having different particle diameters are mixed and used, not only the aggregation between the carbon nanotube particles is reduced, but the carbon nanotubes having a relatively light particle diameter of 1 to 4 nanometers in the dispersion even after a certain time. Is positioned at the top and the carbon nanotubes having a relatively heavy particle diameter of 5 to 8 nanometers are positioned at the bottom to maintain a uniformly dispersed state.

The carbon nanotubes having a particle diameter of 1 to 4 nanometers and the carbon nanotubes having a particle diameter of 5 to 8 nanometers may be mixed in a weight ratio of 1: 0.2 to 1, preferably in a weight ratio of 1: 0.3 to 0.8, more Preferably it may be mixed in a weight ratio of 1: 0.5 to 0.6.

If the weight ratio of the carbon nanotubes having a particle diameter of 5 to 8 nanometers is less than 0.2 with respect to the carbon nanotubes having a particle diameter of 1 to 4 nanometers, the carbon nanotube particles may be aggregated to reduce dispersibility and dispersion stability. When the weight ratio of the carbon nanotubes having a particle diameter of 5 to 8 nanometers is greater than 1, the carbon nanotubes that sink to the lower part of the dispersion are increased. Dispersibility and dispersion stability of the carbon nanotube dispersion may be lowered.

The carbon nanotube dispersion of the present embodiment may include 1 to 8% by weight, preferably 1 to 6% by weight, more preferably 2 to 5% by weight of the carbon nanotubes based on the total weight of the carbon nanotube dispersions . If the carbon nanotube dispersion contains less than 1 wt% of carbon nanotubes based on the total weight of the carbon nanotube dispersion, even if the carbon nanotube dispersion is applied to an electrochemical device or a component, the carbon nanotube dispersion does not exhibit electrical characteristics, and thus it may be meaningless. If the carbon nanotubes contain more than 8% by weight based on the total weight of the nanotube dispersion, there may be a problem in that the carbon nanotubes that do not disperse in the solvent and sink.

In this embodiment, the surfactant may include any one or more selected from the group consisting of sodium dodecyl sulfate, sodium cholate hydrate, and sodium dodecyl benzene sulfonate. have. In particular, in the present embodiment, by using sodium dodecyl sulfate as the surfactant, it is possible to further improve the dispersibility, dispersion stability and adhesion of the carbon nanotube dispersion.

The carbon nanotube dispersion of the present embodiment may include 1 to 5% by weight, preferably 1 to 4% by weight, more preferably 1.5 to 3% by weight of the surfactant based on the total weight of the carbon nanotube dispersion. If the carbon nanotube dispersion contains less than 1 wt% of surfactant based on the total weight of the carbon nanotube dispersion, not only the effect of improving the dispersibility, dispersion stability and adhesion of the carbon nanotube dispersion is generated but also agglomeration between the carbon nanotube particles occurs. There may be a problem that, if the surfactant contains more than 5% by weight based on the total weight of the carbon nanotube dispersion, there may be a problem that the electrostatic properties of the carbon nanotube is reduced.

Polyvinyl butyral, also called polyvinyl butyral, is a resin synthesized by reacting polyvinyl alcohol with butyl aldehyde under an acid catalyst. In the present embodiment, a polyvinyl butyral polymerization degree of 300 to 700 and a butylation degree of about 60 to 65 mol% may be used. If the degree of polymerization of the polyvinyl butyral is less than 300, there may be a problem that the adhesion of the carbon nanotube dispersion is lowered. If the degree of polymerization exceeds 700, the adhesion is improved but the dispersibility and dispersion stability are deteriorated. There may be.

Carbon nanotube dispersion of the present embodiment may include 3 to 25% by weight of the polyvinyl butyral based on the total weight of the carbon nanotube dispersion, preferably 4 to 20% by weight, more preferably 6 to 18% by weight May contain%. If the carbon nanotube dispersion contains less than 3% by weight of polyvinyl butyral based on the total weight of the carbon nanotube dispersion, the adhesion improvement effect may be insignificant, and the polyvinyl butyral based on the total weight of the carbon nanotube dispersion may be used. When it contains more than 25% by weight, the viscosity of the carbon nanotube dispersion becomes high, making it difficult to disperse or apply the carbon nanotube dispersion to the electrochemical device or component, and the viscosity of the polyvinyl butyral causes the carbon nanotube particles to clump. It may form or have a problem.

On the other hand, as described above, the first step of the present embodiment may further include a nano clay (clay), preferably may be nano clay having a particle diameter of 1 to 100 nanometers. The nanoclays of this embodiment may be natural clays, synthetic clays, and mixtures thereof, and for example, laponite, montmorillonite, hectorite, saponite, and baydelite ( Beidellite), nontronite (Nontronite) and the like, but is not limited thereto.

As the nanoclay has an antistatic performance, it is possible to prevent the attraction of the carbon nanotubes in the carbon nanotube dispersion of the present embodiment to agglomeration generated by the attraction of the carbon nanotube particles. However, since the nanoclay is viscous in the wet state, it can be entangled with carbon nanotubes to form agglomerates, and it is preferable to use a small amount because the nanoclay can be adsorbed with carbon nanotubes to form agglomerates.

The carbon nanotube dispersion of the present embodiment may include 0.01 to 0.1% by weight, preferably 0.02 to 0.08% by weight, more preferably 0.03 to 0.05% by weight, based on the total weight of the carbon nanotube dispersion. If the carbon nanotube dispersion contains less than 0.01% by weight of nanoclays based on the total weight of the carbon nanotube dispersion, the antistatic effect of the carbon nanotube may be low, and thus the effect of improving the dispersibility and dispersion stability of the carbon nanotube dispersion may be insignificant. If the nanodispersion is contained in an amount of more than 0.1% by weight based on the total weight of the tube dispersion, carbon nanotubes and nanoclays may be entangled to form lumps, thereby forming a precipitate, which may cause a problem in that dispersibility and dispersion stability are deteriorated. have.

The solvent is water, acetone, dimethyl sulfoxide, dimethylformamide, benzene, benzene, toluene, xylene, chloroform, pyridine, pyridine, Tetrahydrofuran (Tetrahydrofuran), methyl ethyl ketone (methyl ethyl ketone), N-methyl-2- piperidone (N-Methyl-2-pyrrolidone), including but not limited to any one or more selected from the group consisting of carbon Anything that can be applied to the preparation of the nanotube dispersion can be used without limitation.

Carbon nanotube dispersion of the present embodiment may include 65 to 90% by weight, preferably 70 to 90% by weight, more preferably 75 to 90% by weight of the solvent based on the total weight of the carbon nanotube dispersion. If the solvent contains less than 65% by weight of the carbon nanotube dispersion, the viscosity of the carbon nanotube dispersion is increased, so that the usability decreases and a space (solvent) in which the carbon nanotube is uniformly dispersed. There may be a problem that the dispersibility and dispersion stability is not enough due to insufficient, and when the solvent contains more than 90% by weight based on the total weight of the carbon nanotube dispersion, the concentration of carbon nanotubes in the carbon nanotube dispersion is low Chemical properties may be lowered.

(2) In the second step, the mixture is sonicated.

The mixture of the carbon nanotubes, the surfactant, the polyvinyl butyral, the nanoclay, and the solvent prepared in the first step according to the present embodiment may be sonicated for uniform dispersion of the carbon nanotubes. The sonication may be carried out at 20 to 70 kHz, preferably at 20 to 45 kHz, more preferably at 30 to 40 kHz. If the sound wave treatment of the mixture is less than 20 kHz, there may be a problem that the carbon nanotubes are not uniformly dispersed and the dispersibility and dispersion stability is lowered, and the sound wave treatment is performed in excess of 70 kHz. There may be a problem in that the structure of the carbon nanotubes is deformed to deteriorate the characteristics of the carbon nanotubes themselves.

As described above, in the present embodiment, the carbon nanotube dispersion can be prepared by performing a sonic treatment on the mixture as described above. Meanwhile, a separate heating process may be performed in the first and second steps, and the heating may be performed within a range that does not affect the curing of the polyvinyl butyral.

Carbon nanotube dispersion of the embodiment of the present invention prepared as described above is an antistatic material, electrostatic dispersion material, conductive material, electromagnetic shielding material, electromagnetic wave absorbing material, RF (Radio frequency) absorbing material, solar cell material, fuel sensitive battery electrode material , Electronic device material, semiconductor device material, optoelectronic device material, notebook component material, computer component material, mobile phone component material, PDA component material, PSP component material, game machine component material, housing material, transparent electrode material, opaque electrode material, electric field Emission display material, BLU (back light unit) material, liquid crystal display material, plasma display panel material, light emitting diode material, touch panel material, electronic board material, billboard material, display material, heating element, radiator, plating material, catalyst, bath Catalyst, oxidizing agent, reducing agent, automobile parts material, ship parts material, aircraft parts material, protective tape material, adhesive material, tray Materials, Clean Room Materials, Transportation Equipment Parts Materials, Flame Retardant Materials, Antibacterial Materials, Metal Composites, Non-Ferrous Metal Composites, Medical Device Materials, Building Materials, Flooring Materials, Wallpaper Materials, Light Source Components Materials, Lamp Materials, Optical Equipment Components Materials, textile manufacturing materials, clothing manufacturing materials, electrical products materials, electronics manufacturing materials, secondary battery cathode active materials, secondary battery anode active materials, secondary battery materials, fuel cell materials, solar cell materials, memory devices and capacitors (P-ED) <C) may be used as a material, but is not limited thereto.

Hereinafter, the carbon nanotube dispersion of the present invention and its preparation method will be described in detail through Examples, Comparative Examples, and Experimental Examples. Since these examples are only for illustrating the present invention, the scope of the present invention is not to be construed as being limited by these examples.

Example

Example 1

A total of 4.8 g of carbon nanotubes, 2 g of dodecyl sulfate, and polyvinyl butyral (polymerization degree) were mixed with 3 g of carbon nanotubes having a particle diameter of about 3 nanometers and 1.8 g of carbon nanotubes having a particle diameter of about 3 nanometers in the reactor. 400) 15 g and 78.2 g of N-methyl-2piperidone (NMP) were added and stirred (rmp = 250-300) for about 5 minutes to prepare a mixture, which was then heated at 40 kHz for about 60 minutes. A sonication was performed to prepare a carbon nanotube dispersion.

Example 2

A total of 4.8 g of carbon nanotubes, 2 g of dodecyl sulfate, and polyvinyl butyral (polymerization degree) were mixed with 3 g of carbon nanotubes having a particle diameter of about 3 nanometers and 1.8 g of carbon nanotubes having a particle diameter of about 3 nanometers in the reactor. 400) 15 g. 0.05 g of nanoclay (hectorite) having a particle diameter of 30 nanometers and 78.15 g of N-methyl-2 piperidone (NMP) were added thereto, followed by stirring (rmp = 250 to 300) for about 5 minutes to prepare a mixture. Then, this was sonicated for about 60 minutes at 40 kHz to prepare a carbon nanotube dispersion.

Example 3

4 g of carbon nanotubes having a particle diameter of about 3 nanometers and 1.2 g of carbon nanotubes having a particle size of about 6 nanometers were mixed in the same manner as in Example 2 except for 5.2 g of total carbon nanotubes and 77.8 g of NMP. .

Example 4

It was prepared in the same manner as in Example 2 except for using sodium cholate hydrate as a surfactant.

Example 5

Except for using sodium dodecyl benzene sulfonate as a surfactant was prepared in the same manner as in Example 2.

Comparative example

Comparative Example 1

Nanoclay (hectorite) was prepared in the same manner as in Example 2 except for including 1 g and 77.2 g of NMP.

Comparative Example 2

Nanoclay (hectorite) was prepared in the same manner as in Example 2 except for 5 g and NMP 73.2 g.

Comparative Example 3

Carbon nanotubes were prepared in the same manner as in Example 2 except for using only those having a particle diameter of 10 nanometers.

Comparative Example 4

Carbon nanotubes were prepared in the same manner as in Example 2 except for using only 100 nanometers in particle size.

Comparative Example 5

1 g of carbon nanotubes having a particle diameter of about 3 nanometers and 4.8 g of carbon nanotubes each having a particle diameter of about 6 nanometers of 3.8 g were prepared in the same manner as in Example 2.

Comparative Example 6

4.5 g of carbon nanotubes having a particle diameter of about 3 nanometers and 0.3 g of carbon nanotubes having a particle diameter of about 6 nanometers were prepared in the same manner as in Example 2 except that a total of 4.8 g of carbon nanotubes were used.

Comparative Example 7

Carbon nanotubes were prepared in the same manner as in Example 2 except that 0.5 g and NMP 81.95 g were used.

Comparative Example 8

Carbon nanotubes were prepared in the same manner as in Example 2, except that 10 g and NMP 72.95 g were used.

Comparative Example 9

Sodium dodecyl sulfate was prepared in the same manner as in Example 2 except that 0.5 g and NMP 79.65 g were used.

Comparative Example 10

A sodium dodecyl sulfate was prepared in the same manner as in Example 2 except for using 4 g and NMP 76.15 g.

Comparative Example 11

Except for using Triton X-100 as a surfactant was prepared in the same manner as in Example 2.

Comparative Example 12

It was prepared in the same manner as in Example 2 except for using Triton X-405 as a surfactant.

Comparative Example 13

Polyvinylbutyral was prepared in the same manner as in Example 2 except for using 2 g and NMP 91.15 g.

Comparative Example 14

Polyvinylbutyral was prepared in the same manner as in Example 2, except that 30 g and NMP 63.15 g were used.

Comparative Example 15

A polyvinyl butyral was prepared in the same manner as in Example 2 except that the polymerization degree was 100.

Comparative Example 16

A polyvinyl butyral was prepared in the same manner as in Example 2 except that the polymerization degree was 1000.

Experimental Example

Experimental Example  One

After forming a carbon nanotube coating layer having an area of 2 inches and a thickness of 10 micrometers on the surface of the substrate using the carbon nanotube dispersions prepared according to the above Examples and Comparative Examples, the model CNT-SR100N equipment and JADEL 4 Surface resistance was measured using probe probes (the distance between each probe was 20-50 mils). Using the equipment, the surface resistance of five carbon nanotube coating layers was randomly measured, and then the average value thereof was obtained.

	Surface resistance (Ω / sq)		Surface resistance (Ω / sq)
Example 1	13.6	Comparative Example 7	50.6
Example 2	7.1	Comparative Example 8	45.8
Example 3	8.3	Comparative Example 9	58.1
Example 4	8.1	Comparative Example 10	40.9
Example 5	9.2	Comparative Example 11	49.5
Comparative Example 1	98.5	Comparative Example 12	42.5
Comparative Example 2	100.1	Comparative Example 13	32.1
Comparative Example 3	60.5	Comparative Example 14	Not measurable
Comparative Example 4	61.2	Comparative Example 15	29.8
Comparative Example 5	35.6	Comparative Example 16	51.8
Comparative Example 6	38.5

Referring to Table 1, the surface resistance when using the carbon nanotube dispersion according to the embodiment has a value of about 7 to 13, the surface resistance when using the carbon nanotube dispersion according to the comparative example is about 27 ~ 100 It has a value, in the case of Comparative Example 14 can be confirmed that the measurement of the surface resistance due to the viscosity, which means that the dispersion, dispersion stability and adhesion of the carbon nanotube dispersion according to the embodiment of the present invention is remarkably excellent do.

Experimental Example  2

Particle size analyzer (Particle Size Analyzer) using Malvern's Model 2000, and measured the particle size of the carbon nanotube dispersion according to the Examples and Comparative Examples, it is shown in Table 2 below.

In the particle size analysis, one peak (Mono-madal) is formed in the case of complete dispersion, and the particle size distribution is shown in large particles (10 μm) when incomplete dispersion.

	Particle size analysis		Particle size analysis
Example 1	Mono-modal	Comparative Example 7	Incomplete dispersion
Example 2	Mono-modal	Comparative Example 8	Incomplete dispersion
Example 3	Mono-modal	Comparative Example 9	Incomplete dispersion
Example 4	Mono-modal	Comparative Example 10	Incomplete dispersion
Example 5	Mono-modal	Comparative Example 11	Incomplete dispersion
Comparative Example 1	Incomplete dispersion	Comparative Example 12	Incomplete dispersion
Comparative Example 2	Incomplete dispersion	Comparative Example 13	Incomplete dispersion
Comparative Example 3	Incomplete dispersion	Comparative Example 14	Not measurable
Comparative Example 4	Incomplete dispersion	Comparative Example 15	Incomplete dispersion
Comparative Example 5	Incomplete dispersion	Comparative Example 16	Incomplete dispersion
Comparative Example 6	Incomplete dispersion

Looking at Table 2, it can be seen that in the case of Examples 1 to 5 prepared according to the present invention is completely dispersed, in the case of Comparative Examples 1 to 16 it can be seen that incomplete dispersion, which is according to the present invention dispersibility And it means that can be prepared a carbon nanotube dispersion having excellent dispersion stability.

Experimental Example  3

UV absorbance of Example 1, Example 2, Comparative Example 1 and Comparative Example 2 was measured and shown in FIG.

The carbon nanotube dispersions according to Examples 1, 2, Comparative Example 1 and Comparative Example 2 were diluted 100-fold using N-methyl-2piperidone (NMP), and then UV-Visible spectrometer (LAMBDA 750 from Perkinelmer). Model: 190nm ~ 2100nm can be analyzed) their UV absorbance was measured.

 At this time, in Figure 1 design A refers to Comparative Example 2, Design B refers to Comparative Example 1, Design C refers to Example 1, Design D refers to Example 2.

According to Beer's law, the absorbance (the degree of light absorption) is proportional to the concentration of the material, so high absorbance means that the carbon nanotubes that can absorb UV are evenly dispersed in a high concentration.

1, it can be seen that the UV absorbance of the carbon nanotube dispersion of Examples 1 to 2 is superior to Comparative Examples 1 to 2, which is the carbon nanotubes of Examples 1 and 2 compared to Comparative Examples 1 and 2 This means that carbon nanotubes are dispersed evenly in a high concentration. In particular, it can be seen that Example 2 using the nano clay has a higher UV absorbance than Example 1 without the nano clay, which is dispersed evenly in a high concentration in the carbon nanotube dispersion when using the nano clay. It means that the phenomenon can be further improved.

Experimental Example  4

Preparation of carbon nanotube dispersions of Example 2 (sodium dodecyl sulfate), Example 4 (sodium cholate hydrate), Comparative Example 11 (Triton X-100) and Comparative Example 12 (Triton X-405) with different surfactants After that, immediately after the preparation thereof and after 48 hours after the preparation was confirmed, the dispersion stability of the carbon nanotube dispersion was confirmed.

Immediately after the preparation of the carbon nanotube dispersion and after 48 hours is shown in FIG.

2, the carbon nanotube dispersions prepared according to Examples 2 (sodium dodecyl sulfate) and Example 4 (sodium cholate hydrate) are excellent in both dispersibility and dispersion stability immediately after preparation and after 48 hours. Bar, according to this embodiment means that both dispersibility and dispersion stability are excellent.

On the other hand, the carbon nanotube dispersion according to Comparative Example 11 (Triton X-100) can be confirmed that the aggregated mass formed on the surface immediately after the preparation, and after 48 hours it was confirmed that the layer was separated, Comparative Example 11 It can be seen that the dispersibility and dispersion stability is significantly lower than in Examples 2, 4 and Comparative Example 12.

In addition, Comparative Example 12 (Triton X-405) showed a dispersibility similar to that of the Example immediately after preparation, but after 48 hours it can be seen that the layer is separated, it can be seen that the dispersion stability is significantly reduced.

Experimental Example  5

Example 1, Example 2, Comparative Example 1, Comparative Example 2, Comparative Example 16 containing the carbon nanotube dispersion in a vial bottle, immediately after shaking about 10 to 30 times, after 1 hour, after 6 hours, The state after 12 hours is shown in FIGS. 3 and 4.

3 to 4, in the case of Examples 1 to 2, it can be seen that the carbon nanotube dispersion is quickly separated from the surface of the vial bottle compared to the comparative example, from which the carbon nanotube dispersion of Examples 1 to 2 It can be seen that the dispersibility and dispersion stability are excellent. On the other hand, in Comparative Examples 1, 2, and 16, even after 12 hours, the surface of the vial bottle was found to have carbon nanotube lumps, which was not uniformly dispersed in the carbon nanotube dispersion. , Which means that the carbon nanotubes form agglomerates, and from this, it can be seen that the dispersibility and dispersion stability of the carbon nanotube dispersions according to Comparative Examples 1, 2 and 16 are significantly lower than those of the examples.

In addition, looking at Examples 1 and 2, it can be seen that the dispersibility and dispersion stability of Example 2 including the nano clay is better, which means that the dispersibility and dispersion stability is improved according to the use of the nano clay. However, through the comparison of Examples 1 and 2 and Comparative Examples 1 and 2, it can be seen that when the nanoclay is added, but exceeds the weight% presented in the present invention, the dispersibility and dispersion stability is rather reduced.

In addition, it can be seen from the comparison between Example 2 and Comparative Example 16 that the degree of dispersibility and dispersion stability is lowered when the degree of polymerization of polyvinyl butyral does not satisfy the range set forth in the present invention.

As described above, the description of the present invention is for the purpose of illustration, and those skilled in the art to which the present invention belongs may easily change to other specific forms without changing the technical spirit or essential features of the present invention. I can understand. Therefore, it is to be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. .

Claims (16)

1. Carbon nanotubes. Carbon nanotube dispersion comprising a surfactant, polyvinyl butyral and a solvent.
2. The method of claim 1,

   The carbon nanotube dispersion is

   Comprising 1 to 8% by weight of the carbon nanotubes, 1 to 5% by weight of the surfactant, 3 to 25% by weight of the polyvinyl butyral and 65 to 90% by weight of the solvent based on the total weight of the carbon nanotube dispersion Carbon nanotube dispersion liquid.
3. The method of claim 1,

   The carbon nanotube dispersion is a carbon nanotube dispersion, characterized in that it further comprises a nano (Clay).
4. The method of claim 3, wherein

   The carbon nanotube dispersion is

   Carbon nanotube dispersion characterized in that it comprises 0.01 to 0.1% by weight based on the total weight of the carbon nanotube dispersion.
5. The method of claim 1,

   The carbon nanotubes are carbon nanotube dispersion, characterized in that the particle size is 8 nanometer or less.
6. The method of claim 5, wherein

   The carbon nanotubes

   Carbon nanotube dispersion, characterized in that the carbon nanotubes having a particle diameter of 1 to 4 nanometers and carbon nanotubes having a particle diameter of 5 to 8 nanometers are mixed in a weight ratio of 1: 0.2 to 1.
7. The method of claim 1,

   Carbon nanotube dispersion, characterized in that the average degree of polymerization of the polyvinyl butyral is 300 ~ 700.
8. The method of claim 1,

   The surfactant is

   Carbon nanotube dispersion, characterized in that any one or more selected from the group consisting of sodium dodecyl sulfate, sodium cholate hydrate, sodium dodecyl benzene sulfonate.
9. The method of claim 1,

   The solvent is water, acetone, dimethyl sulfoxide, dimethylformamide, dimethylformamide, benzene, toluene, xylene, chloroform, pyridine, pyridine. Tetrahydrofuran (Tetrahydrofuran), methyl ethyl ketone (methyl ethyl ketone), N- methyl-2- piperidone (N-Methyl-2-pyrrolidone), characterized in that it comprises any one selected from the group consisting of Nanotube Dispersion.
10. In the method for producing a carbon nanotube dispersion,

    Carbon nanotubes. A first step of preparing a mixture by mixing a surfactant, polyvinyl butyral and a solvent; And

    Method for producing a carbon nanotube dispersion, characterized in that it comprises a second step of sonicating the mixture.
11. The method of claim 10,

    The carbon nanotube dispersion is

    Comprising 1 to 8% by weight of the carbon nanotubes, 1 to 5% by weight of the surfactant, 3 to 25% by weight of the polyvinyl butyral and 65 to 90% by weight of the solvent based on the total weight of the carbon nanotube dispersion Method for producing a carbon nanotube dispersion, characterized in that.
12. The method of claim 10,

    The method of producing a carbon nanotube dispersion, characterized in that further comprising nanoclay in the first step.
13. The method of claim 12,

    The carbon nanotube dispersion is

    Method for producing a carbon nanotube dispersion, characterized in that it comprises 0.01 to 0.1% by weight based on the total weight of the carbon nanotube dispersion.
14. The method of claim 10,

    The carbon nanotubes have a particle diameter of 8 nanometers or less, characterized in that the manufacturing method of carbon nanotube dispersion.
15. The method of claim 14,

    The carbon nanotubes

    Carbon nanotubes having a particle diameter of 1 to 4 nanometers and carbon nanotubes having a particle diameter of 5 to 8 nanometers are mixed in a weight ratio of 1: 0.2 to 1.
16. The method of claim 10,

    Method of producing a carbon nanotube dispersion, characterized in that the average degree of polymerization of the polyvinyl butyral is 300 ~ 700.

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