KR102172152B1 - High heat resistant carbon nanotubes and polymer composite comprising same - Google Patents

Abstract

The carbon nanotubes according to the present invention are coated with an isoalloxazine derivative to provide a high heat-resistant tanno-tube having improved thermal stability of the carbon nanotubes, and a heat-resistant polymer composite material including the same. The heat-resistant carbon nanotube composite material of the present invention can be more efficiently applied to a conductive polymer material used at a high temperature by improving the thermal stability of the carbon nanotube used as a conductive additive.

Description

High heat resistant carbon nanotubes and polymer composites containing the same {HIGH HEAT RESISTANT CARBON NANOTUBES AND POLYMER COMPOSITE COMPRISING SAME}

The present invention is to provide a polymer composite material having more improved heat resistance by providing a carbon nanotube having a high thermal decomposition temperature.

Thermoplastic resins have excellent processability and moldability and are widely applied to various household goods, office automation equipment, and electrical/electronic products. According to the kind and characteristics of products in which these thermoplastic resins are used, in addition to excellent processability and moldability, thermoplastic resins Attempts are being made to add special properties to resins and use them as high value-added materials.

In particular, if electrical conductivity is given to a material with higher heat resistance than conventional thermoplastic resins among general thermoplastic resins, it is possible to create a material with less particles and evenly distributed electrical conductivity when evaluating frictional contact compared to conventional materials. There have been many attempts to use it as a vehicle, or to use it for a purpose to show electromagnetic wave shielding performance of various electric devices or electronic assemblies.

In order to impart electrical conductivity to such a highly heat-resistant thermoplastic resin, it is generally manufactured by mixing a conductive additive such as carbon black, carbon fiber, metal powder, metal coating, inorganic powder or metal fiber with the thermoplastic resin. However, in the case of a conductive additive, it is difficult to sufficiently secure the desired degree of electrical conductivity unless a significant amount is added (more than 10% by weight), and when a large amount of conductive additive is added, the basic physical properties of a highly heat-resistant thermoplastic resin, for example , There was a problem that mechanical properties such as high heat resistance and impact resistance could be greatly deteriorated.

Accordingly, there have been attempts to impart excellent electrical conductivity while using carbon nanotubes as a small amount of conductive additives, without causing damage to the basic properties of high heat-resistant thermoplastic resins.

Carbon nanotube (carbon nanotube) is a new tube-shaped material with nano-scale diameter made of carbon allotropes, which was first discovered by Dr. Sumio Ijima in 1991. Carbon nanotubes have a strength of 100 times that of iron and more than 20 times of carbon fiber (CF), and have good electrical and thermal properties, so many of the future electric and electronic, information and communication, energy, bio, aerospace and sports fields It is expected to be useful in industry.

Carbon nanotubes have excellent thermal stability at high temperatures, and if this can be further improved, applications in many fields are possible. In particular, studies on increasing the thermal stability of polymers by adding carbon nanotubes to various polymers have been actively conducted, but it has been reported that thermal stability has been increased by tens of degrees by improving the dispersibility of carbon nanotubes with other dispersants. No research is being developed to improve the thermal stability of the nanotube itself.

The problem to be solved by the present invention is to provide a highly heat-resistant carbon nanotube having improved thermal properties by coating a carbon nanotube.

In addition, the present invention is to provide a method of manufacturing the highly heat-resistant carbon nanotubes.

Another problem to be solved by the present invention is to provide a heat-resistant carbon nanotube polymer composite.

Another problem to be solved by the present invention is to provide a molded article made of the heat-resistant polymer composite.

In order to solve the problem of the present invention, the present invention,

It is a carbon nanotube coated with an isoalloxazine derivative, and provides a highly heat-resistant carbon nanotube, characterized in that the thermal decomposition temperature is 100°C or more higher than that of an uncoated case.

The present invention also provides a method for producing the highly heat-resistant carbon nanotube,

Preparing a dispersion solution by adding carbon nanotubes to a mixed solution in which isoalloxazine derivative and solvent are mixed;

Uniformly dispersing the dispersion solution, thereby bonding the isoalloxazine derivative contained in the mixed solution to the surface of the carbon nanotubes;

It provides a method of manufacturing a highly heat-resistant carbon nanotube comprising the step of filtering and drying the carbon nanotubes to which the isoalloxazine derivative is bonded to the surface from the mixed solution.

In order to solve another problem of the present invention, a heat-resistant carbon nanotube polymer composite material including the high heat-resistant carbon nanotube is provided.

In order to solve another problem of the present invention, there is provided a molded article made of the heat-resistant carbon nanotube polymer composite material.

The carbon nanotubes according to the present invention are coated with an isoalloxazine derivative, so that the thermal stability of the carbon nanotubes can be remarkably increased, thereby providing a highly heat-resistant carbon nanotube having improved heat resistance. In addition, the carbon nanotube polymer composite material including the same can provide a polymer composite material with improved conductivity and heat resistance by improving the thermal stability of the carbon nanotube used as a conductive additive, so that it is more efficient as a polymer material used at high temperatures. Can be used as

1 shows a carbon nanotube in which a flan mononucleotide (FMN), one of isoalloxazine derivatives, is helically bonded to the surface.
2 is a powder of high heat-resistant carbon nanotubes prepared according to an embodiment.
3 is a measurement of the thermal decomposition temperature of high heat-resistant carbon nanotubes to which isoalloxazine derivatives are bonded and non-bonded carbon nanotubes according to an embodiment.
4 is a measurement of the thermal decomposition temperature of FMN, an isoalloxazine derivative.
5 is a measurement of the carbon nanotube-isoaloxazine composite prepared according to the Example through a scanning electron microscope and analysis of the length.
Figure 6 is a carbon nanotube-isoaloxazine composite prepared according to the Example was measured through an atomic force microscope (AFM, Atomic Force Microscopy) and analyzed the height and twist.
7 is a measurement of the thermal decomposition temperature of the carbon nanotube-isoaloxazine composite-polymer mixture and the polymer prepared according to the Example.

Terms and words used in this specification and claims should not be construed as being limited to their usual or dictionary meanings, and that the inventor can appropriately define the concept of terms in order to describe his own invention in the best way. Based on the principle, it should be interpreted as a meaning and concept consistent with the technical idea of the present invention.

High heat-resistant carbon nanotubes according to the present invention,

It is a carbon nanotube coated with an isoalloxazine derivative, and provides a highly heat-resistant carbon nanotube, characterized in that the thermal decomposition temperature is 100°C or more higher than that of an uncoated case.

More specifically, the thermal decomposition temperature may appear in the range of 600°C or higher, preferably 630°C or higher, and more preferably 650°C or higher.

According to the present invention,

The isoalloxazine derivative may include the following structure.

[Formula 1]

In the above formula, R is hydrogen or alkyl, and R ₁ and R ₄ are each independently hydrogen, alkyl, hydroxy, halogen atom, halogenated alkyl group, carbonyl group, cyan group, alkoxy group, alkylthio, thi group, allyl group, aryl It is a group or a nitrogen heterocycle, and may preferably be a hydrogen, alkyl, or hydroxy group.

X is hydrogen, alkyl, aromatic or non-aromatic ring, *-CH ₂ -(CHOH)nY, where n is an integer of 1 or 5, and Y is a phosphate ion or phosphate.

Y is, for example, _{* -CH 2 -OPO (OH) 2} , * -CH 2 -OPO (OH) O -, * -CH 2 -OP (= O) O 2 2 - to be.

Here, * indicates the bonding site.

In addition, alkyl, alkoxy, and the like herein may be alkyl or alkoxy having 1 to 10 carbon atoms or 1 to 6 carbon atoms. The aryl group may be a group including a hydrocarbon ring having 6 to 12 carbon atoms, and the non-aromatic ring may be a group including a hydrocarbon ring having 3 to 12 carbon atoms, and the nitrogen hetero ring may be a group including a ring including 1 to 3 nitrogen atoms.

According to an embodiment, the isoalloxazine derivative may be spontaneously adsorbed on the surface of the carbon nanotube material through a pi-pi interaction and bonded to the carbon nanotube surface.

Since the above isoalloxazine derivative is helically and firmly bonded to the surface of the carbon nanotube, unlike other dispersants consisting of alkyl groups, a very robust molecular sieve can be formed on the surface of the carbon nanotube. Since the tube can be very effectively protected, the effect of increasing the thermal decomposition temperature by more than 100°C can be obtained.

According to an embodiment, the isoalloxazine derivative may be one kind of biomolecule, for example, riboflavin, lumiflavin, or derivatives thereof.

According to the present invention, the isoalloxazine derivative, specifically riboflavin or a molecule containing lumiflavin, forms a helical structure when it is bonded with one-dimensional carbon nanotubes through hydrogen bonding due to its structural characteristics, Due to the combination of these molecules, the properties of the surface of the carbon nanotubes are changed, so that the dispersion characteristics can be improved, so that a very stable aqueous solution and a mixed solution of an organic solvent can be prepared.

1 shows that FMN (Flavin monoucleotide), one of the isoalloxazine derivatives, surrounds the carbon nanotube on the surface of the carbon nanotube, and the FMN molecule forms a molecular sieve while forming a spiral along the surface of the carbon nanotube, It indicates that the spiral molecular sieve has a shape surrounding the surface of the carbon nanotube.

Such a helical structure may be caused by hydrogen bonds between the isoalloxazine derivative molecules as described above, such as hydrogen bonds between molecules, the pi-pi interaction between the carbon nanotubes and the isoalloxazine derivative, and electrostatic From the interaction of the miracle attraction and van der Waals attraction, the bonding strength between the molecules of the carbon nanotube and the isoaloxazine derivative and the bonding strength with the carbon nanotubes can be stronger, and the complex in the form of a spiral wrapping the carbon nanotubes is more robust. It can be done. From this, the carbon nanotubes can be chemically and physically protected, and thus, a carbon nanotube having high heat resistance can be obtained.

According to the present invention, the highly heat-resistant carbon nanotube to which the isoalloxazine derivative is bonded,

Preparing a dispersion solution by dispersing carbon nanotubes in a mixed solution in which an isoalloxazine derivative and a solvent are mixed;

Depending on the amount, the dispersion method is ultrasonic pulverization in case of a small amount, and a dispersion method using a ball mill or beads mill is used for mass production, and carbon nanotubes and isoalloxazine derivatives are uniformly mixed. Step to do;

A filtering step of removing excess isoalloxazine derivative not bound to the surface of carbon nanotubes from the mixed solution when the amount of the isoalloxazine derivative is large; And

It may be manufactured by a manufacturing method comprising the step of drying the filtered carbon nanotubes through a freeze drying method.

According to an embodiment, the blending ratio of the carbon nanotubes and the isoalloxazine mixed in the solvent may be 50 to 110 parts by weight of the isoalloxazine based on 100 parts by weight of the carbon nanotubes, preferably 60 to 100 parts by weight, more preferably 70 to 90 parts by weight may be mixed.

According to an embodiment, based on 100 parts by weight of the solvent, the carbon nanotubes may be mixed in an amount of 5 to 20 parts by weight, preferably 5 to 10 parts by weight, and the isoalloxazine is 1 to 20 parts by weight, Preferably 1 to 10 parts by weight, more preferably 1 to 5 parts by weight may be mixed.

The dried isoalloxazine-modified carbon nanotubes may be directly mixed with the polymer and then subjected to a molding process of the composite such as pressure injection, but if the dried carbon nanotubes are too hard, the CNT polymer composite is easily pressed out. I can't. In this case, a small amount of a solvent, preferably water, is added to the dried carbon nanotubes, and then dried through a freeze-drying process to obtain powdery carbon nanotubes, and then mixed with a polymer to be used. At this time, the amount of the added solvent is not particularly limited and may be appropriately selected according to the dispersion and drying efficiency of the carbon nanotubes.

In this case, freeze-drying is a drying method consisting of a sublimation process in which the material is frozen and then the partial pressure is lowered to directly turn the ice into steam. Here, lowering the partial pressure means lowering the pressure below the triple point of the solution. For example, when the solvent is water (H ₂ O), it means that the pressure is lower than the triple point of water, that is, 6 mbar or 4.6 Torr. At this time, moisture in the form of ice under low pressure does not change into liquid by supplying heat energy, but directly sublimates into water vapor.

According to the present invention, the solvent used in the dispersion process is water, ethanol, methanol, acetone, dimethylformamide, dimethyl sulfoxide (DMSO), benzene, toluene, xylene, ethyl acetate, tetrahydrofuran, pyridine, It may be one or more selected from the group consisting of hexane and N-methyl-2-pyrrolidone, and preferably, it may be one selected from water, ethanol, methanol, and acetone.

In addition, the present invention can provide a carbon nanotube polymer composite material with improved heat resistance by mixing the high heat resistance carbon nanotubes with a polymer resin.

In the present invention, the thermal properties of the carbon nanotubes themselves are improved, that is, by adding carbon nanotubes having a thermal decomposition temperature higher than the thermal decomposition temperature of uncoated carbon nanotubes by 100° C. or more, the thermal properties of the polymer resin can also be improved.

In general, carbon nanotubes are added as a conductive additive in a polymer composite, and at this time, physical properties of the polymer itself such as heat resistance and mechanical properties may be deteriorated by the added carbon nanotubes to ensure sufficient conductivity. In order to solve this problem, the present invention can provide a highly heat-resistant carbon nanotube capable of improving not only conductivity but also heat resistance. In addition, according to an embodiment, the carbon nanotubes coated with the isoalloxazine derivative may have improved dispersibility in the polymer resin due to the structural characteristics of the isoalloxazine, from which a small amount of carbon nanotubes are added. It is also possible to obtain the effect of improving the physical properties and conductivity properties of the carbon nanotube composite material.

According to an embodiment, the thermal decomposition temperature of the carbon nanotube polymer composite material may represent a thermal decomposition temperature range of 660° C. or higher, preferably 700° C. or higher, and more preferably 800° C. to 900° C.

Hereinafter, the present invention will be described in detail.

Carbon nanotube

According to an embodiment of the present invention, the specific surface area of the carbon nanotube may be more preferably 40 to 100 m ² /g, and the bulk density is 60 kg/m ³ or less, for example, 10 to 60 kg/m ³ , Preferably it may be 30 to 60kg/m ^{3 and} more preferably 30 to 50 kg/m ³ . As the specific surface area of the carbon nanotubes decreases, the content in the polymer composite may increase, but dispersibility and density may decrease. In addition, as the bulk density decreases, the dispersibility in the polymer resin decreases, so that aggregates of carbon nanotubes may be formed in the composite material, which may be a factor deteriorating mechanical and electrical properties.

In addition, the content of carbon nanotubes contained in the polymer composite may be 1 to 15% by weight, preferably 1 to 10% by weight, more preferably 5 to 10% by weight, based on the total weight of the composite, and the 1% by weight When included in a lower content, physical properties may not be sufficiently improved.

Accordingly, the present invention can prepare a polymer composite material with remarkably improved excellent physical properties, particularly mechanical strength, by optimizing the content and dispersibility of the carbon nanotubes in the composite by controlling the specific surface area and bulk density of the carbon nanotubes together. .

In addition, the average size of the carbon nanotube aggregates included in the polymer composite injection product may be 5 μm or less, which is an index indicating improved dispersibility of the composite material, and may exhibit an effect on improving the physical properties of the composite material.

In addition, the average aspect ratio of the carbon nanotubes included in the polymer composite material may be 1 to 100, preferably 10 to 60, more preferably 10 to 30.

In addition, the diameter of the carbon nanotubes included in the polymer composite material may be 20 to 100 nm, preferably 30 to 100 nm.

The average length and aspect ratio of the carbon nanotubes can be measured through SEM (Scanning Electron Microscope) or TEM (transmission electron microscope) photographs. That is, after obtaining a picture of the powdery carbon nanotube as a raw material through these measuring devices, it is analyzed through an image analyzer, for example, Scandium 5.1 (Olympus soft Imaging Solutions GmbH, Germany) to determine the average length. Can be obtained.

According to one embodiment, the carbon nanotubes used as raw materials have an average particle size of about 5 μm to 1,000 μm, or 100 to 800 μm, preferably 200 μm to 600 μm, more preferably 300 μm to 400 μm. It may be, and the thickness may have a range of 10nm to 1,000㎛. Bundle-shaped carbon nanotubes having an average length and thickness in this range may be more advantageous in improving the conductivity of the thermoplastic polymer-containing composite. The carbon nanotubes have a network structure in the matrix of the polymer composite material containing the thermoplastic polymer, and the carbon nanotubes having a long length are more advantageous in the formation of such a network, and as a result, the physical properties of the polymer composite can be improved. .

The carbon nanotube of the present invention may satisfy a strand diameter of 10 to 50 nm, and may be a potato or spherical entangled type having a flatness of 0.9 to 1.0 and a particle size distribution value (D carbon nanotube) of 0.5 to 1.0. have.

The term "bulk density" used in the present invention is defined by Equation 1 below, and by controlling the firing temperature of the supported catalyst and increasing the reaction temperature during carbon nanotube synthesis, the density distribution of the carbon nanotubes grown therefrom is also specified. It can have a range.

[Equation 1]

Bulk density = Carbon nanotube weight (kg) / Carbon nanotube volume (m ³ )

Further, the flatness and the bundle type can be obtained by a unique process of manufacturing using the supported catalyst of the present invention described above. At this time, the flatness is defined by Equation 2 below.

[Equation 2]

Flatness = the shortest diameter through the center of the carbon nanotube / the maximum diameter through the center of the carbon nanotube.

Furthermore, the particle size distribution value (D _CNT ) may be defined by Equation 3 below.

[Equation 3]

D _CNT = [Dn90-Dn10] / Dn50

In the formula, Dn90 is the number average particle diameter measured under a 90% criterion in the absorption mode using a Microtrac particle size analyzer after putting the carbon nanotubes in distilled water for 3 hours, and Dn10 is the number average particle diameter measured under 10% , And Dn50 is the number average particle diameter measured under the 50% standard.

The carbon nanotubes according to the present invention may be prepared using a supported catalyst calcined at 600° C. or lower using a spherical α-alumina support, and more preferably prepared by the following manufacturing method.

In order to manufacture the carbon nanotube,

A catalyst component and an active component are supported on a spherical α-alumina support, and a supported catalyst calcined at 600° C. or lower is introduced into the reactor, and a carbon source or the carbon supply source into the reactor at a temperature of 650° C. or more and less than 800° C. And injecting hydrogen gas, nitrogen gas or a mixture thereof; And

It may be produced by a method comprising: growing carbon nanotubes through decomposition of the carbon source injected on the surface of the catalyst.

That is, the present invention uses an α-alumina support, but by controlling the catalyst firing temperature and reaction temperature, the BET specific surface area is 40 m ² /g to 120 m ² /g, and the bulk density is less than 60 kg / m ³ Tubes can be manufactured.

The supported catalyst for synthesizing carbon nanotubes according to an embodiment is characterized in that the catalyst component and the active component are supported on a spherical α-alumina support, and fired at 600° C. or less.

In general, alumina having the formula of Al ₂ O ₃ exists in several different phases, for example α-, γ-, δ-, η-, θ- and Χ-alumina. In α-alumina (corundum), oxide ions form a hexahedral densely packed structure, and alumina ions are symmetrically distributed in the octahedral cleft. Likewise, γ-alumina has a "defective" spinel structure (a spinel structure without cation).

In addition, the support of the catalyst may include α-alumina. Although γ-alumina has high utility as a catalyst support due to its high porosity, it is known that α-alumina has very low porosity and very low utility as a catalyst support. Surprisingly, when a supported catalyst is prepared using spherical α-alumina as a support, the diameter is reduced by reducing the specific surface area while suppressing the generation of amorphous carbon during the synthesis of carbon nanotubes by controlling the firing temperature at which the supported catalyst is formed. It becomes possible to control.

As described above, the supported catalyst for synthesizing carbon nanotubes according to the present invention is technically characterized in that the catalyst component and the active component are supported on a spherical α-alumina support, and are fired at a temperature of 600°C or less. Examples of the temperature include a range of 400°C to 600°C. While the supported catalyst calcined in such a temperature range minimizes the generation of amorphous carbon when synthesizing carbon nanotubes, it is possible to improve dispersion in the polymer by controlling the specific surface area, diameter and bulk density of the carbon nanotubes.

In the spherical α-alumina used in the present invention, the term "spherical shape" includes a substantially spherical shape in addition to a complete spherical shape, and may also include a case in which the cross section has an elliptical shape such as a potato shape.

According to one embodiment, the spherical α-alumina may be prepared by a method known in the art. For example, the Bayer method for producing alumina from bauxite is widely used industrially. Likewise, spherical α-alumina can be prepared by heating γ-Al ₂ O ₃ or any hydrogen-containing oxide to above 1000°C.

The spherical α-alumina used as a support in the present invention may be of any suitable dimension. For example, the spherical α-alumina used in the present invention may have a surface area of, for example, about 1 m ² /g to about 50 m ² /g as measured by the BET method. In the present invention, the spherical α-alumina used as a support has a very low porosity due to its smooth surface unlike a conventional support, and may have a pore volume of, for example, 0.001 to 0.1 cm ³ /g.

The spherical α-alumina as a support may have a relatively low content of metal supported, and as the metal, for example, a catalyst component and an active ingredient are about 10 to 25 parts by weight based on 100 parts by weight of the spherical α-alumina, Alternatively, it may be supported in an amount of about 15 to 20 parts by weight. Sufficient catalytic activity may be exhibited in such a supported content.

The catalytic component and the active component supported on the spherical α-alumina may be used in a weight ratio of 10 to 30:1 to 14, and it is possible to exhibit better carbon nanotube production activity within this content range.

The catalyst component used in the present invention may be at least one selected from Fe, Co, and Ni. For example, Fe salt, Fe oxide, Fe compound, Co salt, Co oxide, Co compound, Ni salt, Ni oxide, Ni compound It may be one or more selected from the group consisting of, in another example Fe(NO ₃ ) ₂ ·6H ₂ O, Fe(NO ₃ ) ₂ ·9H ₂ O, Ni(NO ₃ ) ₂ ·6H ₂ O, Co(NO ₃ ) It may be a nitride such as ₂ · 6H ₂ O.

In addition, the active ingredient used in the present invention may be one or more of Mo and V as an example, and as another example may be a Mo salt, Mo oxide, Mo compound, V salt, V oxide, V compound, etc. A nitride such as (NH ₄ ) ₆ Mo ₇ O ₂₄ ·4H ₂ O can be dissolved in distilled water and used.

The supported catalyst for synthesizing carbon nanotubes of the present invention as described above can be prepared by an impregnation method.

According to one embodiment, the method for producing a supported catalyst for synthesizing carbon nanotubes according to the present invention,

(1) forming an aqueous solution containing a supported catalyst precursor by mixing a spherical α-alumina support with an aqueous metal solution containing a catalyst component precursor and an active component precursor;

(2) aging and impregnating the aqueous solution containing the supported catalyst precursor to obtain a mixture;

(3) vacuum drying the mixture to coat the catalyst component and the active component on the surface of the support; And

(4) sintering the resultant product obtained by vacuum drying at a temperature of 600° C. or less to form a supported catalyst.

In step (1) of the above manufacturing method, an aqueous solution containing a supported catalyst precursor is formed, and this aqueous solution is formed by mixing an Al-based support with a metal aqueous solution containing a catalyst component precursor and an active component precursor. Components and a spherical α-alumina support are included, and these are as already described above.

When considering the impregnation efficiency, the concentration of the metal aqueous solution is more efficient to use, for example, in the range of 0.1 to 0.4 g/ml, or 0.1 to 0.3 g/ml. The content of the spherical α-alumina support mixed in such a metal aqueous solution is as described above, for example, the catalyst component and the active ingredient are about 10 to 25 parts by weight based on 100 parts by weight of the spherical α-alumina, or It can be used to be supported in an amount of about 15 to 20 parts by weight.

In step (2) of the manufacturing method, the supported catalyst precursor solution is aged and impregnated to obtain a mixture, and the aging impregnation is not limited thereto, but in a temperature range of 20°C to 100°C, or 60°C to 100°C. It can be performed for 30 minutes to 15 hours, or 1 to 15 hours, and it is possible to provide high loading efficiency in such a range.

In step (3) of the preparation method, the mixture resulting from the aging impregnation obtained in step (2) is vacuum-dried to coat the surface of the support with the catalyst component and the active component. The vacuum drying is drying by rotary evaporation under vacuum. For example, it can be performed within 1 hour or 1 minute to 1 hour under 45° C. to 80° C., and the excess metal salt remaining without impregnation in the support is removed. It is possible to provide a uniform coating impregnation of the alumina surface through the drying process.

In the vacuum drying described herein, the meaning of "vacuum" is not particularly limited if it falls within the vacuum range that is usually applied to vacuum drying.

In step (4) of the manufacturing method, the resultant obtained by vacuum drying in step (3) is calcined to form the supported catalyst of the present invention, which is the final product. Such firing is performed in the range of about 400°C to 600°C. It can be carried out, and can be carried out in air or under an inert atmosphere. The firing time is not limited thereto, but may be performed within about 30 minutes to 5 hours.

According to an embodiment, after vacuum drying in step (3), pre-firing may be performed at least once at about 250° C. to 400° C. before firing in step (4). In this case, the entire loading is carried out immediately before pre-firing. The efficiency of the reaction is that up to 50% of the aqueous catalyst precursor solution is impregnated into the amorphous α-alumina support, and the balance of the supported catalyst precursor aqueous solution is impregnated into the spherical α-alumina support immediately after or immediately before the preliminary firing. It is preferable from the side.

Although not limited thereto, the bulk shape of the supported catalyst prepared as described above depends on the bulk shape of the spherical α-alumina support used. That is, the supported catalyst for synthesizing carbon nanotubes has a spherical shape in a bulk shape, and may have a structure in which a catalyst component is mainly coated on a surface of a support with one or more layers (two or three or more layers), and these have a continuous coating layer structure. Rather, it may be preferable in terms of carbon nanotube synthesis to have a discontinuous coating structure.

The supported catalyst for manufacturing carbon nanotubes provided in the present invention, for example, has a particle diameter or average particle diameter of about 30 to about 150 μm, and may have a surface particle size of about 10 nm to 50 nm when observed by SEM, and this range It is preferable in terms of carbon nanotube diameter control and catalytic activity.

On the other hand, the supported catalyst coated with the catalytic component and the active component on the surface of the spherical α-alumina support has a particle diameter of 32 µm or less based on the measurement of the particle diameter of the alumina support in consideration of the particle diameter or average particle diameter range of the alumina support. When defined as a fine fraction, the number average particle diameter measured value may have a range of 5% or less, specifically 3% or less.

For reference, in the ultrasonic process, the fine powder is an aggregate of the catalyst material and the active material attached to the catalyst, and is not filtered out when sieved, but the particle size and catalytic activity are different from the catalyst-active material well coated on the support. As such, the yield of carbon nanotubes is significantly reduced due to the island-like aggregates attached to the catalyst, and since the materials are somewhat weakly attached to the catalyst, they are separated during ultrasonics and fine powder is generated.

In the present invention, the ultrasonic fine fraction refers to the number average particle diameter fine fraction measured through a particle size analyzer after the ultrasonic treatment, and in this case, the support includes multilayer support.

In particular, the supported catalyst for synthesizing carbon nanotubes obtained by the present invention is preferably spherical in view of the specific surface area, and the supported catalyst for synthesizing carbon nanotubes actually prepared in the present invention is also spherical, almost spherical, or substantially spherical. Closeness was identified.

The process of producing carbon nanotubes from the supported catalyst obtained by the above method includes, but is not limited to, the following steps:

Injecting the supported catalyst according to the present invention into the reactor, and injecting a carbon source or the carbon source and hydrogen gas, nitrogen gas, or a mixture gas thereof into the reactor at a temperature of about 650 ℃ to about 800 ℃; And

It is possible to provide a method for producing carbon nanotubes, including growing carbon nanotubes through decomposition of a carbon source injected on the surface of the catalyst.

According to an embodiment, as the reactor, a fixed bed reactor or a fluidized bed reactor may be used without limitation.

According to the carbon nanotube manufacturing method of the present invention, it becomes possible to manufacture a carbon nanotube having an entangled secondary structure and a spherical bulk shape, as identified in the following examples.

Thermoplastic polymer

When considering the moldability, it is preferable to use the thermoplastic polymer having a measured relative viscosity of 1.5 to 5, more preferably 2 to 4.5, measured under conditions of a concentration of 1 g/dl at 25°C. If the relative viscosity is less than 1.5, since it has a low viscosity, processing after melt-kneading becomes difficult and it may become difficult to obtain desirable physical properties. Further, if it is larger than 5, the fluidity during molding is poor due to the high viscosity, and since sufficient injection pressure is not applied, it may become difficult to make a molded article.

In addition, the thermoplastic polymer according to the present invention preferably has a melt index of 0.5 to 100 g/min, more preferably 1.0 to 80 g/min, and if the melt index is less than 0.5 g/min, a high shear force is required and thus melting Kneading is difficult, the dispersion of carbon nanotubes in the thermoplastic polymer is difficult, and when the melt index exceeds 100 g/min, the impact strength of the molded product may be seriously deteriorated.

The thermoplastic polymer that can be used in the conductive composite material may be used without limitation as long as the thermoplastic polymer is used as a thermoplastic polymer in the related industry. For example, polycarbonate resin, polypropylene resin, aramid resin, aromatic polyester resin, polyolefin Resin, polyester carbonate resin, polyphenylene oxide resin, polysulfone resin, polyethersulfone resin, polyarylene resin, cycloolefin resin, polyetherimide resin, polyacetal resin, polyvinyl acetal resin, polyketone resin, Polyether ketone resin, polyether ether ketone resin, polyaryl ketone resin, polyether nitrile resin, liquid crystal resin, polybenzimidazole resin, polyparavanic acid resin, polyamide resin,

A vinyl polymer or copolymer resin obtained by polymerization or copolymerization of at least one vinyl monomer selected from the group consisting of aromatic alkenyl compounds, methacrylic acid esters, acrylic acid esters and vinyl cyanide compounds,

Diene-aromatic alkenyl compound copolymer resin, vinyl cyanide-diene-aromatic alkenyl compound copolymer resin, aromatic alkenyl compound-diene-vinyl cyanide-N-phenylmaleimide copolymer resin, vinyl cyanide-(ethylene-diene- At least one selected from the group consisting of propylene (EPDM))-aromatic alkenyl compound copolymer resin, vinyl chloride resin, and chlorinated vinyl chloride resin may be used. Specific types of these resins are well known in the art, and examples that can be used in the composition of the present invention may be appropriately selected by those skilled in the art.

The polyolefin resin may be, for example, polypropylene, polyethylene, polybutylene, and poly(4-methyl-1-pentene), and combinations thereof, but is not limited thereto. In one embodiment, the polyolefin is a polypropylene homopolymer (e.g., atactic polypropylene, isotactic polypropylene, and syndiotactic polypropylene), a polypropylene copolymer (e.g. For example, polypropylene random copolymer), and mixtures thereof. Suitable polypropylene copolymers include, but are not limited to, the presence of a comonomer selected from the group consisting of ethylene, but-1-ene (i.e. 1-butene), and hex-1-ene (i.e. 1-hexene). And a random copolymer prepared from polymerization of propylene under. In such polypropylene random copolymers, the comonomer may be present in any suitable amount, but is typically in an amount of about 10 wt% or less (e.g., about 1 to about 7 wt%, or about 1 to about 4.5 wt%). Can exist.

As said polyester resin, homopolyester or copolymerized polyester which is a polycondensation body of a dicarboxylic acid component skeleton and a diol component skeleton is said. Here, examples of the homopolyester include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, poly-1,4-cyclohexanedimethylene terephthalate, and polyethylene diphenylate. Etc. are representative. In particular, polyethylene terephthalate is inexpensive, so it can be used for a wide variety of applications, and is therefore preferable. In addition, the copolymer polyester is defined as a polycondensate composed of at least three or more components selected from components having a dicarboxylic acid skeleton and a component having a diol skeleton as exemplified below. As a component having a dicarboxylic acid skeleton, terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4' -Diphenyldicarboxylic acid, 4,4'-diphenylsulfone dicarboxylic acid, adipic acid, sebacic acid, dimer acid, cyclohexanedicarboxylic acid and their ester derivatives. As a component having a glycol skeleton, ethylene glycol, 1,2-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentadiol, diethylene glycol, polyalkylene glycol, 2,2-bis( 4'-β-hydroxyethoxyphenyl)propane, isosorbate, 1,4-cyclohexanedimethanol, spiroglycol, and the like.

The polycarbonate resin may be prepared by reacting diphenols with phosgene, halogen formate, carbonate ester, or a combination thereof. Specific examples of the diphenols include hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, 2,2-bis(4-hydroxyphenyl)propane (also referred to as'bisphenol-A'), 2, 4-bis(4-hydroxyphenyl)-2-methylbutane, bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 2,2-bis(3-chloro -4-hydroxyphenyl)propane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane, 2 ,2-bis(3,5-dibromo-4-hydroxyphenyl)propane, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)ketone, bis(4-hydroxyphenyl) Ether and the like. Among these, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane or 1,1-bis(4-hydroxyphenyl) Cyclohexane may be used, and more preferably 2,2-bis(4-hydroxyphenyl)propane may be used.

The polycarbonate resin may be a mixture of a copolymer prepared from two or more diphenols. In addition, the polycarbonate resin may be a linear polycarbonate resin, a branched polycarbonate resin, a polyester carbonate copolymer resin, or the like.

Examples of the linear polycarbonate resin include bisphenol-A-based polycarbonate resin. Examples of the branched polycarbonate resin include those prepared by reacting a polyfunctional aromatic compound such as trimellitic anhydride and trimellitic acid with diphenols and carbonates. The polyfunctional aromatic compound may be included in an amount of 0.05 to 2 mol% based on the total amount of the branched polycarbonate resin. Examples of the polyester carbonate copolymer resin include those prepared by reacting a difunctional carboxylic acid with diphenols and carbonates. At this time, as the carbonate, diaryl carbonate such as diphenyl carbonate, ethylene carbonate, and the like may be used.

Examples of the cycloolefin polymer include norbornene polymers, monocyclic cyclic olefin polymers, cyclic conjugated diene polymers, vinyl alicyclic hydrocarbon polymers, and hydrides thereof. Specific examples thereof include Arpels (ethylene-cycloolefin copolymer manufactured by Mitsui Chemicals), Atone (norbornene-based polymer manufactured by JSR), and Zeonoa (norbornene-based polymer manufactured by Nippon Xeon Corporation).

The polyphenylene oxide resin is also referred to as polyphenylene ether, and has a structure in which -O- is bonded to a phenylene group as a repeating unit. The phenylene group may have various substituents, such as a methyl group, an ethyl group, a halogen group, and a hydroxy group.

As the polyamide resin, nylon resins, nylon copolymer resins, and mixtures thereof can be used. Examples of nylon resins include polyamide-6 (nylon 6) obtained by ring-opening polymerization of lactams such as ε-caprolactam and ω-dodecalactam, which are commonly known; Nylon polymers obtained from amino acids such as aminocapronic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid; Ethylenediamine, tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 5-methylnonahexamethylenediamine , Metaxylenediamine, paraxylenediamine, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis( 4-aminocyclohexane)methane, bis(4-methyl-4-aminocyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane, bis(aminopropyl)piperazine, aminoethylpiperidine, etc. Aliphatic, alicyclic or aromatic diamines and aliphatic, alicyclic or aromatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, terephthalic acid, 2-chloroterephthalic acid, and 2-methylterephthalic acid, etc. Nylon polymer obtainable from polymerization of; Copolymers or mixtures thereof may be used. As a nylon copolymer, a copolymer of polycaprolactam (nylon 6) and polyhexamethylene sebacamide (nylon 6,10), a copolymer of polycaprolactam (nylon 6) and polyhexamethyleneadiphamide (nylon 66), And a copolymer of polycaprolactam (nylon 6) and polylauryllactam (nylon 12).

Other additives

The conductive composite material is a flame retardant, flame retardant aid, lubricant, plasticizer, heat stabilizer, drip inhibitor, antioxidant, compatibilizer, light stabilizer, pigment, dye, inorganic additive and drip inhibitor, provided that it does not affect conductivity and physical properties. It may further include one or more additives selected from the group consisting of, the content of which is 20 parts by weight or less, preferably 15 parts by weight or less, more preferably, based on 100 parts by weight of the conductive composite material, that is, the carbon nanotube high powder composite material. May be used in an amount of 10 parts by weight or less. Specific types of these additives are well known in the art, and examples that can be used in the composition of the present invention may be appropriately selected by those skilled in the art.

The conductive composite material according to the present invention may be manufactured through a pressure injection process, and in general, the extrusion process is a molding method in which raw materials are supplied to an extruder and pushed out of a structure in the form of a heating cylinder to convert it into a continuous body having a certain shape. The raw material of the conductive composite material supplied to the extruder is heated in a cylinder, softened and melted, and transported while being kneaded and compressed by rotation of the screw. The flow of the raw material in a uniform melt is continuously extruded to the outside from the opening of the mold made in the desired shape, and then cooled, the extrusion result is obtained.

In such an extrusion process, the material properties may change while undergoing a kneading process under mechanical pressure in a heated state.For example, in the case of a microstructured carbon nanotube, mechanical cutting occurs, so the carbon nanotube remaining in the extrusion result Can have a different shape from the carbon nanotubes supplied as raw materials. Therefore, it is preferable to proceed with the extrusion process while maintaining the physical properties of the raw material, and for this, it is necessary to appropriately control the extrusion conditions of the extruder. In the present invention, damage to raw materials can be suppressed by controlling the rotational speed of the rotating screw mounted on the extruder.

In the present invention, the shape of the extruder is not limited, but can be classified as a single screw extruder with one screw or a multiscrew extruder with a plurality of screws, and the multi-screw extruder has two screws for uniform mixing of additives. A twin screw extruder can be illustrated.

When a twin-screw extruder is used as the extruder, there is no particular limitation on the screw of the twin-screw extruder, and screws such as a fully meshed type, an incompletely meshed type, and a non-engaged type may be used. From the viewpoint of kneading properties and reactivity, a fully engaged screw is preferred.

In addition, the screw may be rotated in the same direction or in the reverse direction, but rotation in the same direction is preferable from the viewpoint of kneading properties and reactivity. The screw is most preferably a co-rotating fully engaged type.

According to an embodiment, in order to suppress thermal deterioration of the resin in the extrusion process, an inert gas may be introduced from the raw material input portion to be melt-kneaded, and nitrogen or the like may be exemplified as the inert gas at this time.

As a kneading method using such an extruder, a thermoplastic resin and a carbon nanotube are mixed together, a resin composition (master pellet) containing a high concentration of carbon nanotubes in a thermoplastic resin is prepared, and then a specified concentration A method of melt-kneading by adding the resin composition and carbon nanotubes (master pellet method) to be exemplified, and any kneading method may be used. As another method, in order to suppress the damage of the carbon nanotubes, a method of melt-kneading by introducing a thermoplastic resin from the extruder side and feeding the carbon nanotubes to the extruder using a side feeder can be exemplified.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto, and is merely an example for describing the present invention in more detail.

Example 1- Preparation of carbon nanotubes to which isoalloxazine derivatives are bound.

Multi-walled carbon nanotubes (g): water (mL): FMN (g) = 1: 20: A sample mixed in a ratio of 0.8 is milled for 5 minutes through a ball milling method to prepare. The ball mill used at this time was a Pulverisette 5 device manufactured by FRITSCH, Germany.

When the amount of the isoalloxazine derivative is large, the mixed solution is filtered under reduced pressure with a filter membrane having a pore size of 0.2 µm to remove the excess isoalloxazine derivative.

The carbon nanotube solids obtained by filtration under reduced pressure were completely removed from excess water through a vacuum drying oven. If the dried sample is hard and is not suitable for the pressure injection process with the polymer, the dried sample was mixed with water again and then freeze-dried to obtain a powdered dried multi-walled carbon nanotube-isoaloxazine sample. . The powder of the multi-walled carbon nanotube-isoaloxazine sample is shown in FIG. 2.

Comparative Example 1

Carbon nanotubes without surface treatment used in Example 1.

Experimental Example 1

The carbon nanotubes prepared in Example 1 and Comparative Example 1 were measured using a thermogravimetric analysis (TGA-Q500). When the temperature was raised from room temperature to 900°C at 5/min in a nitrogen atmosphere, the temperature of the portion where the inflection point appeared was confirmed. The results are shown in FIG. 3.

In the pyrolysis measurement, the carbon nanotubes manufactured according to the present invention may have an initial mass reduction section, Fig. 4 shows the thermal decomposition measurement results of the coating material isoalloxazine derivative. As can be seen in FIG. 4, the initial mass reduction at 200 to 300°C can be interpreted as due to thermal decomposition of the alkyl group of the isoalloxazine derivative, through which the initial mass reduction of the carbon nanotubes manufactured according to the present invention is It appears to be due to the coating material coated on the surface. Therefore, it can be seen that the thermal decomposition temperature of the carbon nanotubes starts near the inflection point where a more rapid mass decrease appears.

Experimental Example 2

The carbon nanotube-isoaloxazine composite prepared in Example 1 was dispersed in water using agitation, applied to a silicon substrate, and then the length of the carbon nanotube was analyzed through a scanning electron microscope. The change in the length of the carbon nanotubes according to the ball milling time is shown in FIG. 5.

The lengths of about 100 individually dispersed carbon nanotubes were measured and averaged according to the ball milling time. As can be seen in FIG. 5, it can be seen that the length of the carbon nanotubes decreases as the milling time increases. In particular, when the milling time was 5 minutes, the average length of the carbon nanotubes was 2.23 µm, but when the milling time was 30 minutes, the length of the carbon nanotubes was 2.08 µm and gradually decreased. In addition, it was confirmed that there was almost no change in length to about 1.46 µm at the milling time longer than that. Through this, it was confirmed that the length of the carbon nanotubes can be adjusted by adjusting the ball milling time.

Experimental Example 3

After dispersing the carbon nanotube-isoaloxazine composite in water using agitation, it was applied to a silicon substrate, and the shape of the carbon nanotube was measured with an atomic force microscope (AFM). The shape of the measured carbon nanotube-isoaloxazine composite is shown in FIG. 6. 6A is a measurement of the height image of the twisted carbon nanotubes in a size of 2 µm X µm, and B to D show the height of the carbon nanotube bundle according to the twist position. At the top of the picture, you can clearly observe how the bundles of carbon nanotubes, which were entangled in a spiral form, unfold into individual tubes as they go downward. Moreover, in the case of individual carbon nanotubes, it can be confirmed that there is also a twist. In the case of B, the height is approximately 13 nm, which is almost identical to the 11 nm diameter of the carbon nanotubes provided. In the case of C, the height is about 25 nm, and it appears that the two strands are twisted. D represents the height of a single strand, which is about 13 nm, which corresponds to the diameter of the carbon nanotube. In addition, as the measured width of the tube indicates several hundred nm, it appears that several strands of carbon nanotubes are twisted by themselves and twisted together.

Example 2

40 g of carbon nanotubes prepared in Example 1 were mixed with 1960 g of polycarbonate (PC) and 20 g of other additives. The obtained polymer mixture was then extruded in a twin screw extruder (L/D=42, Φ=40mm) while raising the temperature profile to 280 to prepare pellets having a size of 0.2mm X 0.3mm X 0.4mm. The prepared pellets were injected from an injection machine under the condition of a flat profile with an injection temperature of 280°C to prepare a specimen having a thickness of 3 mm, a length of 163 mm, and a dog-bone type.

Experimental Example 4

The dogbone specimen prepared in Example 2 was measured using a thermogravimetric analysis (TGA-Q500). When the temperature was raised by 10/min from room temperature to 600℃ in a nitrogen atmosphere, the temperature of the part with a mass loss of 5% compared to the initial mass was confirmed.

Experimental Example 5

PC pellets and the pellets prepared in Example 2 and Comparative Example 2 were measured using a thermogravimetric analyzer (TA Instruments, Hi-Res TGA 2950), and the results are shown in FIG. 7. When the temperature was raised from room temperature to 700°C at 5/min in an air atmosphere, the end temperature of pyrolysis of the pellet prepared in Example 2, in which the carbon nanotube-isoaloxazine composite and PC are mixed, is about 40 than that of PC. You can see the ℃ increase. Considering that about 2 wt% of the carbon nanotube-isoalloxazine composite is contained in the pellet, it can be seen that if the ratio of the composite is increased, more improved thermal stability can be exhibited.

As described above, specific parts of the present invention have been described in detail, and for those of ordinary skill in the art, it is obvious that these specific techniques are only preferred embodiments, and the scope of the present invention is not limited thereby. something to do. Therefore, it will be said that the practical scope of the present invention is defined by the appended claims and their equivalents.

Claims (21)

It is a carbon nanotube coated with an isoalloxazine derivative, but the thermal decomposition temperature is 100°C higher than that of the case not coated with the isoalloxazine derivative, and the thermal decomposition temperature of the coated carbon nanotube is 600°C or higher, and the carbon nanotubes High heat-resistant carbon nanotubes, characterized in that the tube is a multi-walled carbon nanotube. delete The method of claim 1,
High heat-resistant carbon nanotubes wherein the isoalloxazine derivative comprises the following structure:
[Formula 1]

In the above formula, R is hydrogen or alkyl, and R ₁ and R ₄ are each independently hydrogen, alkyl, hydroxy, halogen atom, halogenated alkyl group, carbonyl group, cyan group, alkoxy group, alkylthio, thi group, allyl group, aryl Group or nitrogen heterocycle,
X is hydrogen, alkyl, aromatic or non-aromatic ring, a group of the general formula -CH ₂ -(CHOH)nY, where n is an integer of 1 or 5, and Y is a phosphate ion or phosphate salt. The method of claim 1,
High heat-resistant carbon nanotubes wherein the isoalloxazine derivatives are spontaneously adsorbed on the surface of carbon nanotubes through pi-pi interactions. The method of claim 1,
High heat-resistant carbon nanotubes in which the isoalloxazine derivatives spirally surround the carbon nanotubes along the surface of the carbon nanotubes. The method of claim 1,
The isoalloxazine derivative is riboflavin, lumiflavin, or a derivative thereof. High heat-resistant carbon nanotubes. The method of claim 1,
The isoalloxazine derivative is a phosphate salt or sodium phosphate salt of riboflavin, a highly heat-resistant carbon nanotube. delete The method of claim 1,
High heat-resistant carbon nanotubes having an average particle size of 100 µm to 800 µm. The method of claim 1,
High heat-resistant carbon nanotubes, wherein the carbon nanotubes have a secondary structure of potato or spherical entangled type. Preparing a dispersion solution by adding carbon nanotubes to a mixed solution in which isoalloxazine derivative and solvent are mixed;
Uniformly dispersing the dispersion solution, and bonding the isoalloxazine derivative to the surface of the carbon nanotubes; And
It includes the step of filtering and drying the carbon or tube to which the isoalloxazine derivative is bonded to the surface from the mixed solution,
The carbon nanotubes are multi-walled carbon nanotubes, and the thermal decomposition temperature of the produced carbon nanotubes is 600°C or higher. The method of claim 11,
The dispersion method of the dispersion solution is a method of manufacturing a highly heat-resistant carbon nanotube by using a dispersion method using ultrasonic waves, a ball mill, or a beads mill. The method of claim 11,
Mixing a predetermined amount of a solvent with the dried carbon nanotubes; And
Freeze-drying the carbon nanotubes mixed with the solvent
The method of manufacturing a highly heat-resistant carbon nanotube further comprising a. The method according to any one of claims 11 to 13,
The solvent is water, ethanol, methanol, acetone, dimethylformamide, dimethylsulfoxide (DMSO), benzene, toluene, xylene, ethylacetate, tetrahydrofuran, pyridine, hexane, N-methyl-2-pi Method for producing a highly heat-resistant carbon nanotube that is one or more selected from the group consisting of rolidone. The method of claim 11,
A method of manufacturing a highly heat-resistant carbon nanotube, wherein the isoalloxazine is mixed in an amount of 50 to 110 parts by weight based on 100 parts by weight of the carbon nanotube. The method of claim 11,
Based on 100 parts by weight of the solvent, 5 to 20 parts by weight of the carbon nanotubes and 1 to 20 parts by weight of the isoalloxazine are mixed in a high heat-resistant carbon nanotube production method. A carbon nanotube polymer composite material comprising a high heat-resistant carbon nanotube and a polymer resin according to any one of claims 1, 3 to 7, and 9 and 10. The method of claim 17,
A carbon nanotube polymer composite material having a thermal decomposition temperature of 660° C. or higher of the carbon nanotube polymer composite material. The method of claim 17,
Carbon nanotube polymer composite material in which the polymer resin is a thermoplastic resin. The method of claim 17,
The carbon nanotube polymer composite material containing 1 to 10 parts by weight of the highly heat-resistant carbon nanotubes based on 100 parts by weight of the polymer resin. A molded article made of the carbon nanotube polymer composite material according to claim 17.

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