KR20120053861A - Methods for the preparation of carbon nanotubes covalentely modified by poly(aryleneether)s - Google Patents

Abstract

PURPOSE: A modified carbon nano-tube and a manufacturing method of carbon nano-tube in which poly(arylene ether) based polymer is attached are provided to grow poly(arylene ether) based polymer from an initiator by using a chain-growth condensation polymerization. CONSTITUTION: A modified carbon nano-tube has an initiator which is attached to the nano-tube and is represented by chemical formula 1. The modified carbon nanotube is manufactured by precursor of an initiator which is represented by chemical formula 2. A complex carbon nanotube is manufactured by polymerization of monomers which forms a poly(arylene ether) based polymer and the modified carbon nanotube. A manufacturing method of the complex carbon nanotube comprises next steps: chain growth condensation polymerizing the monomer represented by chemical formula 3 and the modified carbon nano-tube which has an initiator; and manufacturing a complex carbon nanotube.

Description

Method for preparing carbon nanotubes to which poly (arylene ether) polymer is attached {methods for the preparation of carbon nanotubes covalentely modified by poly (aryleneether) s}

The present invention relates to a method for preparing a composite carbon nanotube to which a poly (arylene ether) polymer, which is an engineering plastics-based condensation polymer, is attached. More specifically, an initiator capable of causing chain growth condensation polymerization may include carbon nanotubes. The present invention relates to a method for producing a composite carbon nanotube to which a poly (arylene ether) -based polymer, which is a condensation polymer, is attached to a surface of a polymer and chain growth of a monomer using a nucleophilic substitution reaction therefrom. In addition, the present invention relates to an initiator precursor having two kinds of functional groups capable of attaching with carbon nanotubes and causing chain growth polymerization, and monomers grown by a chain growth polymerization method not previously reported.

In order to cope with the depletion of human available fossil energy sources and global warming, research and development of alternative energy resources such as solar energy, geothermal energy, wind power, and hydrogen energy are being actively conducted worldwide. However, in the situation where fossil energy cannot be replaced entirely due to various problems such as conversion efficiency with low utilization of alternative energy, another alternative is to develop a method to use energy more efficiently. For example, it is a method of increasing energy-to-kinetic efficiency by using alternative energy sources as an auxiliary means or using lightweight functional materials while using existing energy sources such as gasoline / rechargeable battery hybrid vehicle technology or solar housing.

In recent years, active research is being conducted on carbon allotrope. Among them, carbon nanotubes have been applied for various purposes because of their extremely light and excellent mechanical and electrical properties since they were first reported by Iijima Group of NEC in Japan in 1991. Research is underway.

The carbon nanotubes produced at the early stage had a problem of commercialization because the production cost was very high and the form was not constant.However, due to continuous technology development such as laser deposition method and vapor deposition method developed by Smalley group and Ren group, respectively, Mass production has become possible, and purity and its form can be controlled.

However, another barrier is bundled by the very large length-to-diameter ratio of the carbon nanotubes and van der Waals forces, so it has very low dispersion and does not mix well with any medium, which is very limited in practical use. Is that there is. Therefore, much research has been conducted on the development of dispersion technology of carbon nanotubes, which can be roughly divided into physical dispersion and chemical modification. The physical method is to prevent the aggregation by enclosing the tube using molecules designed to temporarily weaken the cohesion between nanotubes by applying ultrasonic waves or to make secondary interaction with the surface of the nanotubes. However, this physical dispersion method has a high possibility of re-agglomeration and it is difficult to transfer the properties of the carbon nanotubes to the medium sufficiently. On the other hand, chemically modifying carbon nanotubes can fundamentally block the possibility of reagglomeration, and by selecting the appropriate molecules for the medium, it is possible to transfer the properties of the nanotubes to the medium sufficiently.

In terms of industrial applications, many studies have been conducted to attach polymers to surfaces of carbon nanotubes. The method of attaching a polymer can be broadly divided into two methods: growing a polymer first and then attaching it to the surface of the nanotube, and attaching an initiator capable of initiating polymerization to the surface of the nanotube, and then selectively There is a way to grow. The former method is easy to grow a polymer to a desired size, but it is difficult to attach many polymers due to the large size of the polymer in the step of attaching to the surface of the nanotube. The latter method has to devise an appropriate initiator structure, which must have both a functional group capable of reacting with carbon nanobubble and a functional group capable of initiating polymerization, and the polymerization initiating functional group is stable in the attachment step with the nanotubes. Should be maintained. Currently, the attachment of initiators to various polymerizations has been developed, and has been successfully applied to anionic polymerization, atom transfer radical polymerization, nitrooxide mediated polymerization, coordination polymerization, ring-opening polymerization, ring-opening northern decomposition polymerization. However, there is no example of growing a poly (arylene ether) -based polymer, which is a kind of engineering plastic, from an initiator attached to carbon nanotubes.

Poly (arylene ether) -based polymers having aromatic derivatives and ether linkages are not only heat-resistant but also excellent in mechanical properties, durability, chemical resistance, etc. and, as a commercial product ^{Udel TM (Poly (ether sulfone)} ), PEEK TM (Poly (ether ether ketone)) ( more than ^{Amoco社), Ultem TM (Poly} (ether imide)), PPO TM (Poly (phenylene oxide )) (Above GE) is commercialized. Generally, poly (arylene ether) -based condensation polymers grow according to a step growth mechanism, and the resulting polymers have a polydispersity of 2 or more. However, the use of specially designed monomers and initiators with leaving groups activated by strong electron drag groups allows the growth of condensation polymers in a chain-growth fashion. The polymer thus formed is close to polydispersity 1 and the length of the chain can be easily adjusted.

An object of the present invention is to provide a carbon nanotube with an initiator attached to a poly (arylene ether) -based polymer, which is not previously reported, to be grown by a chain growth condensation polymerization mechanism using a nucleophilic substitution reaction. It is done.

Another object of the present invention is to provide an initiator having a functional group capable of reacting with carbon nanotubes, which have not been previously reported, to form a covalent bond and a functional group capable of causing chain growth condensation polymerization.

Another object of the present invention is to provide a monomer that is grown by a chain growth condensation polymerization method which has not been reported previously.

Another object of the present invention is to provide a method of growing a poly (arylene ether) -based polymer from a initiator attached to a carbon nanotube by a chain growth condensation polymerization method using a nucleophilic substitution reaction.

It is another object of the present invention to provide a method for preparing carbon nanotubes to which poly (arylene ether) based polymers are grown by a step growth condensation polymerization method using a nucleophilic substitution reaction, which has not been previously reported. do.

Still another object of the present invention is to provide a dissolving carbon nanotube having excellent dispersibility and dissolvability in a solvent to which a poly (arylene ether) -based polymer grown by the chain growth condensation polymerization method or the step growth condensation polymerization method is attached. For the purpose.

The present invention relates to a method for preparing a composite carbon nanotube to which a poly (arylene ether) polymer, which is an engineering plastics-based condensation polymer, is attached. More specifically, an initiator capable of causing chain growth condensation polymerization may include carbon nanotubes. The present invention relates to a method for producing a composite carbon nanotube to which a poly (arylene ether) -based polymer, which is a condensation polymer, is attached to a surface of a polymer and chain growth of a monomer using a nucleophilic substitution reaction therefrom. In addition, the present invention relates to an initiator precursor having two kinds of functional groups capable of attaching with carbon nanotubes and causing chain growth polymerization, and monomers grown by a chain growth polymerization method not previously reported.

In the present invention, "carbon nanotube" means single-walled or multi-walled carbon nanotubes themselves, and "modified carbon nanotubes" means chain growth obtained by reacting carbon nanotubes with an initiator precursor capable of causing chain growth condensation polymerization. It refers to carbon nanotubes to which an initiator capable of causing condensation polymerization is attached, and "composite carbon nanotube" refers to a poly (arylene ether) polymer-carbon nanotube composite in which the modified carbon nanotubes and a monomer are polymerized. do.

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

The present invention provides a modified carbon nanotube (hereinafter referred to as CNT-I) having an initiator attached thereto, which can cause chain growth condensation polymerization represented by the following Chemical Formula 1.

[Formula 1]

은

또는

이고;[remind

silver

or

ego;

R is CF ₃ or CN;

X is F, Cl or NO ₂ ;

n is an integer of 1 or more and 10 to 10 carbon atoms of the carbon nanotube. 1 for every 100.]

In the chemical formula 1, carbon nanotubes are single-walled or multi-walled carbon nanotubes, and R is an electron-withdrawing group such as trifluoromethyl group or cyanide group and is present in the ortho position with respect to X. The leaving group X is a fluoro, chloro or nitro group, Ar is a benzene or diphenyl amide structure and n is an integer of 1 or more. 1 for every 100.

는 보다 상세히 하기 구조로부터 선택된다.remind

Is selected from the following structures in more detail.

The initiator precursor having the structure is covalently linked to the carbon nanotubes and by controlling the concentration of the reaction conditions 10 carbon atoms of the carbon nanotubes? One initiator per 100 may be adjusted to be substituted. The initiators attached to the carbon nanotubes are intimate with the hydroxide anions of the monomers in which the fluorine group or the nitro leaving group is activated by the trifluoromethyl group or cyanide group, which is an electron withdrawing group, and can cause chain growth polymerization. May cause a nuclear substitution reaction. However, since the leaving group of the monomer has high electron density due to the hydroxide anion, the activity is greatly decreased, and the nucleophilic substitution reaction between the monomers hardly occurs, so the polymer grows from the initiator attached to the carbon nanotubes.

In another aspect, the present invention provides an initiator precursor having two kinds of functional groups capable of attaching to carbon nanotubes represented by the following Chemical Formula 2 and causing chain growth polymerization.

[Formula 2]

[Y is N ₂ BF ₄ or NH ₂ ;

은

또는

이고;

silver

or

ego;

R is CF ₃ or CN;

X is F, Cl or NO ₂ ]

Y group of the initiator of Formula 2 is a diazonium tetrafluoro boron functional group or an amine group as a functional group capable of covalent bonding with carbon nanotubes. R is a trifluoro methyl group or cyanide group and is in the ortho position relative to X. X is a fluoro or nitro group and Ar is a benzene or diphenyl amide structure. The initiator precursor is at least one selected from the following compounds in more detail.

The initiator precursor of Chemical Formula 2 has a diazonium tetrafluoro boron functional group or an amine functional group, which is a functional group attachable to carbon nanotubes. The attachment method is described in J. Am . When the Y group is a diazonium tetrafluoro boron functional group . Chem . Soc . , 2005 , 127 , 14867-14870 and are amine groups in J. Am . Chem . Soc . , 2003 , 125, 1156-1157. The initiator precursor may be a diazonium tetrafluoroborone functional group in which a fluorine or nitro leaving group activated by an electron attracting group capable of causing chain growth condensation polymerization is used in the reaction process in which the initiator precursor is attached to the carbon nanotube. Since they are used independently of the amine functional groups, they are characterized in that they are not damaged during the attachment process of the initiator precursor.

In another aspect, the present invention provides a monomer that is grown by a chain growth polymerization method not previously reported represented by the following formula (3).

(3)

은 하기 구조에서 선택되고;[

Is selected from the following structures;

X 'is F, Cl or NO ₂ ]

The monomer of Formula 3 includes a potassium hydroxide functional group, R 'is a trifluoro methyl group and is in the ortho position relative to X'. X 'is a fluoro, chloro or nitro group and Ar is a benzene or sulfonated diphenyl sulfone or azobenzene structure. The said monomer, ie, the monomer grown by the chain growth condensation method, is 1 or more types specifically selected from the following compounds.

Generally, in order to synthesize poly (arylene ether) -based polymers grown by step growth condensation method by chain growth condensation polymerization method, firstly, monomers and initiators should be able to react with each other, but monomers and initiators should react with each other. After reacting with the initiator, the leaving group must be activated to react with the next monomer. In order to achieve the above object, the activity of the initiator leaving group must be higher than that of the monomer leaving group, which can be achieved by proper design of the monomer and the initiator. In order to reduce the activity of the monomer leaving group, if the hydroxy group, a nucleophilic attack group, is formed in the form of a high electron density hydroxide anion, the electron structure of the leaving group increases due to the resonance structure, thereby decreasing the activity for the nucleophilic substitution reaction. . Thus, nucleophilic substitution reactions between monomers are suppressed as much as possible. On the other hand, the initiator has to increase the activity of the leaving group to react with the monomer, and if the strong electron attracting group is placed in the ortho or para position of the leaving group, the electron density becomes lower and is activated. Unlike the leaving group of the monomer, the hydroxide It is possible to cause nucleophilic substitution reactions with anions. After the monomer has reacted with the initiator, the para position of the monomer leaving group is changed from the hydroxide anion to the phenyl ether form, so that the electron density of the leaving group is lowered and activated than the monomer, and the reaction with the hydroxide anion of the next monomer occurs. It becomes possible. In this way, since the polymerization occurs only at the end of the monomer reacted with the initiator, the polymer grows in a chain growth mode. The above monomers are monomers which have not been previously reported and satisfy all of the above conditions.

In addition, the present invention is a composite carbon nanotube (Formula 4) and chain-growth condensation polymerization prepared by condensation polymerization of CNT-I (modified carbon nanotube, Formula 1) and monomer (Formula 3) It provides a method for producing the same).

[Formula 4]

[Wherein,

은

또는

이고;

silver

or

ego;

R is CF ₃ or CN;

은 하기 구조에서 선택되고;

Is selected from the following structures;

X 'is F, Cl or NO ₂ ;

m is an integer from 1 to 400; And

l is an integer equal to or less than n of CNT-I in formula (1).]

As shown in Scheme 1 below, CNT-I (modified carbon nanotube, Chemical Formula 1) and monomer (Formula 3) are used to generate a nucleophilic substitution reaction in a chain growth mode to attach a poly (arylene ether) polymer. Composite carbon nanotubes were prepared.

Scheme 1

[Wherein l, m, n are integers and n is an integer of 1 or more, the carbon atoms of the carbon nanotube 10? 1 per 100, and m is 1? An integer between 400 and l is an integer less than or equal to n.]

The method for preparing a composite carbon nanotube to which a poly (arylene ether) based polymer is attached by causing a nucleophilic substitution reaction in a chain growth method includes the following steps:

1) dissolving CNT-I (modified carbon nanotube, Formula 1) and monomer (Formula 3) in a polar aprotic solvent;

2) dipping and stirring in a preheated (120-210 ° C.) oil bath;

3) after the reaction, the step of immersing in a polar solvent in which the polymer is well dissolved; And

4) Filter the filter with a pore size smaller than the size of the carbon nanotubes used.

When the monomer represented by Formula 3 reacts with the initiator attached to the modified carbon nanotube, the leaving group is activated, and since the remaining monomers can only react with the activated leaving group, the polymer is selectively modified carbon nano It grows only in the tube and it is easy to control the length of the chain by controlling the concentration of the monomer. In addition, when grown by the chain growth method, a poly (arylene ether) -based polymer having a constant length can be obtained close to the polydispersity index 1, and the final form of the composite carbon nanotube is a carbon nanotube having a relatively constant poly ( Arylene ether) polymer is enclosed.

In addition, the present invention is a method for producing a composite carbon nanotubes by step-growth condensation polymerization of the monomer forming the CNT-I (modified carbon nanotube, Formula 1) and the poly (arylene ether) polymer To provide an example is shown in Scheme 2 below.

Scheme 2

The poly (arylene ether) -based polymer is poly (ether sulfone), poly (ether ketone), poly (ether ether sulfone), poly (ether ether ketone), poly (ether imide), poly (arylene ether) and At least one selected from poly (arylene ether amide), the monomer used in the step growth condensation polymerization may be any known monomer as long as it is a monomer forming the poly (arylene ether) polymer. For example, the monomer represented by following formula (5) can also be used.

[Chemical Formula 5]

은 하기 구조에서 선택되고;[

Is selected from the following structures;

X 'is F, Cl or NO ₂ ]

The monomer of Chemical Formula 5 may be specifically exemplified by the following compound.

The CNT-I (modified carbon nanotube, Formula 1) can also be used for the attachment of poly (arylene ether) based polymers grown by step growth and includes the following steps:

1) CNT-I (modified carbon nanotube, Formula 1), a monomer forming a poly (arylene ether) polymer, and 1? Dissolving 2 equivalents of potassium carbonate in a polar aprotic solvent;

2) azeotropic distillation by adding benzene or toluene and raising the temperature (80-130 ° C.);

3) raising the temperature further (120-210 ° C.) and stirring;

4) after the reaction, the step of immersing in a polar solvent in which the polymer is well dissolved; And

5) Filter by a filter having a pore size smaller than the size of the carbon nanotubes used.

The polymers grown by the step growth condensation polymerization method grow in response to the monomers in the reaction solution, but some grow from the initiator like the chain growth method. However, the polymer grown by the step growth method in a solution other than the initiator may react with the leaving group of the initiator attached to the carbon nanotubes, so that the polymer may be connected with the carbon nanotubes during the reaction even if it does not grow from the initiator.

Polar aprotic solvents used in the chain growth condensation polymerization and step growth condensation polymerization include N-methylpyrrolidone, dimethyl sulfoxide, N, N-dimethylacetamide, N, N-dimethylformamide, di It is at least one selected from the group consisting of phenyl sulfone and sulfolane.

In addition, the present invention is a poly-condensate grown by a chain growth condensation polymer or a step growth condensation polymerization method of a monomer to form a poly (arylene ether) -based polymer using the CNT-I (modified carbon nanotube, Formula 1) Provided is a composite carbon nanotube to which an (arylene ether) -based polymer is attached.

In the composite carbon nanotubes of the present invention, poly (arylene ether) -based polymers are covalently attached, so that they are easily dispersed in various organic solvents or polymer media. This is because the attached polymer prevents the carbon nanotubes from agglomerating again. Thus, the solubility and dispersibility of the condensation polymer can be improved by using carbon nanotubes to produce a composite having overall uniform characteristics. In addition, the mechanical and electrical properties of the condensation polymer can be further improved. You can expect In addition, in the technical field of attaching a polymer having a controlled length to the carbon nanotubes, the technology development has been reported only for the additional polymer, but in the present invention, the chain growth condensation polymerization method is used to easily control the length of the condensation polymer, thereby controlling the carbon nanotubes. By reporting the technology that can be attached to the carbon nanotubes, the choice of polymers that can be attached to the carbon nanotubes can be expanded.

It is possible to grow or attach condensation polymer using modified carbon nanotubes to which the initiator according to the present invention is attached, and to increase the solubility and dispersibility of carbon nanotubes by attaching the condensation polymer. Therefore, when preparing a composite, that is, composite carbon nanotubes using the modified carbon nanotubes according to the present invention, a composite (composite carbon nanotubes) having overall uniform characteristics may be prepared. In addition, better mechanical and electrical properties due to polycondensation polymers can be expected. In addition, in the technical field of attaching a polymer having a controlled length to the carbon nanotubes, the technology development has been reported only for the additional polymer, but in the present invention, the length of the axially fused polymer can be easily adjusted using an initiator attached to the modified carbon nanotube. It can be adjusted and attached. In addition, by mixing a modified carbon nanotube with an initiator and a monomer forming a commercially available arylene ether-based condenser and causing a nucleophilic substitution reaction, a composite carbon nanotube with a poly (arylene ether) polymer can be easily prepared. have. In the present invention, by reporting a technology that can be attached to the arylene ether-based polymers to expand the choice of polymers that can be attached to the carbon nanotubes and to simultaneously utilize the properties of the carbon nanotubes and the excellent mechanical and electrical properties of the condensation polymer Material may be provided.

1 illustrates a process of attaching a poly (arylene ether) -based polymer provided in the present invention to carbon nanotubes.
2 is a scheme corresponding to Examples 1 and 2 of the present invention.
3 is a nuclear magnetic resonance spectroscopy spectrum of an initiator capable of attaching to carbon nanotubes prepared in the preparation of the present invention and causing chain growth condensation polymerization.
FIG. 4 shows the color of the solution and the UV / UV of the solution over the course of the reaction time when preparing single-walled carbon nanotubes (SWNT-PPO) to which poly (3-trifluoromethylphenylene oxide) is attached in Example 2. FIG. Visible / near-infrared spectrum.
Figure 5 is a single-walled carbon nanotube (SWNT-PPO) attached to the poly (3- trifluoromethylphenylene oxide) prepared in Example 2 of the present invention and the poly (3- trifluoromethylphenyl prepared in Comparative Example Ethylene oxide) (CF ₃ -PPO) nuclear magnetic resonance spectroscopy spectra (a) and infrared spectra (b).
6 is a scheme (a) and gel permeation chromatography analysis (b) of poly (3-trifluoromethylphenylene oxide) (CF ₃ -PPO) prepared in Comparative Example of the present invention.
FIG. 7A shows the results of differential scanning calorimetry of single-walled carbon nanotubes (SWNT-PPO) to which poly (3-trifluoromethylphenylene oxide) prepared in Example 2 of the present invention is attached.
7B shows the results of differential scanning calorimetry of poly (3-trifluoromethylphenylene oxide) (CF ₃ -PPO) prepared in Comparative Example.
7C shows the results of differential scanning calorimetry of a 1:10 mixture of carbon nanotubes and poly (3-trifluoromethylphenylene oxide) (CF ₃ -PPO) prepared in Comparative Example.
8 is a scheme of a single-walled carbon nanotube to which poly (arylene ether amide) prepared in Example 3 of the present invention is attached.
9 is a nuclear magnetic resonance spectroscopy spectrum according to the temperature of the poly (arylene ether amide) attached single-wall carbon nanotube prepared in Example 3 of the present invention
10A is a scanning electron micrograph and energy dispersive X-ray spectrum of CNT-I prepared in Example 1 of the present invention.
10B is a scanning electron micrograph and energy dispersive X-ray spectrum of a single-walled carbon nanotube (SWNT-PPO) to which poly (3-trifluoromethylphenylene oxide) prepared in Example 2 of the present invention is attached.
10C is a scanning electron micrograph and energy dispersive x-ray spectrum of a 1:10 mixture of carbon nanotubes and poly (3-trifluoromethylphenylene oxide) (CF ₃ -PPO) prepared in Comparative Example.
11A is a scanning electron micrograph and energy dispersive X-ray spectrum of CNT-I prepared in Example 1 of the present invention.
FIG. 11B is a scanning electron micrograph and energy dispersive X-ray spectrum of a single-walled carbon nanotube to which a poly (arylene ether amide) prepared in Example 3 of the present invention is attached.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the following Examples are for the purpose of explanation and are not intended to limit the present invention.

The structure and physical properties of the monomers and polymers according to the examples were confirmed and measured using the following method.

The structure of the synthesized material was confirmed from IR (infrared spectroscopy) and NMR (nuclear magnetic resonance spectroscopy). IR plots were obtained using Bruker's EQUINOX-55, and NMR plots were obtained by dissolving samples in dimethyl sulfoxide-d ₆ using Bruker's Fourier Transform AVANCE 400 spectrometer. The molecular weight of the polymer synthesized from gel permeation chromatography was measured, and the sample was dissolved in tetrahydrofuran to measure the molecular weight based on polystyrene standard polymer using T60A of Viscotec. Differential scanning calorimetry (DSC) was measured under a nitrogen stream at a rate of 20 ° C./min using TA instrument's TA-Q100, and the melting temperature (Tm) was selected from the DSC plot. The polymer attached to the carbon nanotubes was observed by scanning electron microscopy (SEM) and the elements of the polymer were detected by energy dispersive X-ray spectroscopy (EDAX). The solubility of carbon nanotubes was confirmed by ultraviolet / visible / near infrared spectroscopy using JASCO's V-670.

Manufacturing example : Initiator  4- precursor Fluoro -3- ( Trifluoromethyl ) Of benzenediazonium tetrafluoroborate  synthesis

Slowly add 4-fluoro-3-trifluoromethylaniline (7.16 g) to a mixed solution of 8.0 mole tetrafluorobolic acid (14 ml) and distilled water (15 ml), and then cool the solution to 0 ° C. . Sodium nitrate (2.9 g) is dissolved in distilled water (6.5 ml), and slowly dropped to prevent the temperature of the previously prepared aniline solution from rising over 1 hour. At this time, a yellow precipitate is formed, and finely crushed with a spectula. After stirring for 30 minutes at 0 ℃ filter the precipitate. The precipitate is placed in an excess of diethyl ether, stirred for 30 minutes, and the precipitate is filtered. The previous step is carried out once more, filtered and dried in vacuo at room temperature to give a pale yellow final product (7.78 g; 70% yield).

¹ H NMR (400 MHz, DMSO- d ₆ , 25 ° C): δ [ppm] = 9.31 (d, 1H, J = 3.2 Hz, Ar H ), 9.08 (d, 1H, J = 8.4 Hz, Ar H ) , 8.17 (dd, 1H, J ₁ = 9.5 Hz, J ₂ = 9.5 Hz, Ar H ). (FIG. 3A)

¹³ C NMR (100 MHz, DMSO- d ₆ , 25 ° C): δ 165.20 (d, J _{C -F} = 273 Hz), 141.05 (d, J _{C -F} = 13 Hz), 134.21 (m), 121,51 (d, J _{C -F} = 24 Hz), 120.58 (q, ¹ J _{C -F} = 272 Hz), 119.22 (q, ² J _{C -F} = 19 Hz), 113.47 (d, J _{C -F} = 3 Hz). (FIG. 3B)

Example  1: 4- Fluoro -3- Trifluoromethyl Benzoyl Single wall  Modified carbon nanotubes ( SWNT-I)  synthesis

Single Wall Carbon Nanotubes (0.2 mg), 4-fluoro-3- (trifluoromethyl) benzenediazoniumtetrafluoroborate (Preparation, 46.41 mg), 1-hexyl-4-methylpyridinium tetra Add fluoroborate (0.4 ml) to the agate trigger and grind for 10 minutes with a pestle. Add potassium carbonate (0.5 mg) and grind for another 5 minutes. The black product is filtered with a 0.2 um nylon filter. At this time, wash sufficiently with N, N'-dimethyl formamide (DMF), methanol, acetone and distilled water. The filtered product was placed in N, N'-dimethyl formamide solution, sonicated for about 3 minutes and filtered again with a 0.2 um nylon filter. Do this again and dry in an oven at 50 ° C (1.9 mg). (Figure 2)

Example  2: poly (3- Trifluoromethylphenylene Oxide ) Is attached Single wall  Carbon nanotubes ( SWNT - PPO ) Synthesis

In a shrink flask, 4-fluoro-3-trifluoromethyl benzoyl single-walled carbon nanotube (Example 1, 3 mg) and excess potassium 4-fluoro-3-trifluoromethylphenoxide (0.3 g) Dimethyl sulfoxide (6 ml) was added and then ultrasonicated for 1 minute. After three freeze-pump-thaw cycles with liquid nitrogen, immerse in an oil bath heated to 130 ° C and stir for 6 days. After the reaction, cool to room temperature and slowly pour into 1: 1 mixture of methanol and distilled water. The precipitate is filtered and dissolved again in a N, N'-dimethylacetamide solvent, and then slowly poured into a tetrahydrofuran solution. Stir for 30 minutes and filter using a 0.2 um nylon filter. The black final product is dried in a vacuum oven at 50 ° C. (12.1 mg). (Figure 2)

¹ H NMR (400 MHz, DMSO- d ₆ , 25 ° C.): δ [ppm] = 7.47 (br, 1H, Ar H ), 7.26 (br, 1H, Ar H ), 7.19 (br, 1H, Ar H ) .

Example  3: Poly (arylene ether amide)  Attached Single wall  Preparation of Carbon Nanotubes

4-fluoro-3-trifluoromethyl benzoyl single wall carbon nanotube (4.56 mg), 4-nitro-3-trifluoromethyl-N- (2-nitro-4-hydroxyphenyl) benzamide (0.46 g), potassium carbonate (0.26 g) is added to dimethyl sulfoxide, and then ultrasonic waves are applied for 1 minute. Benzene (0.9 ml) is added and azeotropic distillation at 90 ° C. for 4 hours. At this time, when all the added benzene is distilled, 0.9 ml of benzene is added again to continue azeotropic distillation. The temperature was raised to 120 ℃ and stirred for 20 hours, then cooled to room temperature. Slowly pour the reaction solution into distilled water to which a small amount of acetic acid is added, collect the precipitate, collect it, dissolve it in N, N'-dimethylacetamide solvent, and slowly pour it into tetrahydrofuran solution. Stir for 30 minutes and filter using a 0.2 um nylon filter. The black final product is dried in a 50 ° C. vacuum oven. (20 mg)

¹ H NMR (400 MHz, DMSO- d ₆ , 25 ° C.): δ [ppm] = 10.9 (br, 1H, CON H ), 8.41 (br, 1H, Ar H ), 8.29 (br, 1H, Ar H ) , 7.84 (d, 1H, J = 8.7 Hz, Ar H ), 7.79 (br, 1H, Ar H ), 7.63 (br, 1H, Ar H ), 7.41 (br, 1H, Ar H ).

Comparative example  : Poly (3- Trifluoromethylphenylene Oxide ) ( CF ₃ - PPO ) Synthesis

4-fluoro-3- (trifluoromethyl) benzene (1 mg), potassium 4-fluoro-3- (trifluoromethyl) phenoxide (0.6 g) and dimethylsulfoxide were placed in a shrink flask After freezing, three freeze-pump-thaw cycles are carried out using liquid nitrogen, and then immersed in an oil bath heated to 130 ° C. and stirred for 6 days. After the reaction, cool to room temperature and slowly pour into 1: 1 mixture of methanol and distilled water. The precipitate is filtered and then dissolved in N, N'-dimethylacetamide solvent and poured slowly into methanol. Stir for 30 minutes and filter the precipitate. The light gray final product is dried in a vacuum oven at 50 ° C. (31 mg). (FIG. 6A)

¹ H NMR (400 MHz, DMSO- d ₆ , 25 ° C): δ [ppm] = 7.49 (s, 1H, Ar H ), 7.29 (d, 1H, J = 8.8 Hz, Ar H ), 7.18 (d, 1H, J = 8.8 Hz, Ar H ).

In order to observe the increase in solubility of single-walled carbon nanotubes (SWNT-PPO) to which poly (3-trifluoromethylphenylene oxide) was attached with polymerization time, samples were taken at regular time intervals in the experiment of Example 2, It is shown in Figure 4 that the solubility of the carbon nanotubes is gradually increased with the growth of the polymer by measuring the visible light / near infrared spectrum.

Figure 5 is a single-walled carbon nanotube (SWNT-PPO) attached to the poly (3- trifluoromethylphenylene oxide) prepared in Example 2 of the present invention and the poly (3- trifluoromethylphenyl prepared in Comparative Example butylene oxide) (CF ₃ nuclear magnetic resonance spectroscopy spectra (a) and infrared spectrum (b), the poly (3-methyl-phenyl alkylene oxide) trifluoromethyl (CF ₃ -PPO, comparative) and poly -PPO) ( Comparing the NMR spectra (a) of single-walled carbon nanotubes (SWNT-PPO, Example 2) to which 3-trifluoromethylphenylene oxide) was attached, it was found that the peaks of the two materials were the same polymer. In the case of SWNT-PPO, the peaks appear wide because the polymer is attached to the support. In addition, single-walled carbon nanotubes (SWNT-PPO, Example 2) to which poly (3-trifluoromethylphenylene oxide) (CF ₃ -PPO, Comparative Example) and poly (3-trifluoromethylphenylene oxide) were attached. The FT-IR spectrum (b) of) shows that single-walled carbon nanotubes do not absorb light in the IR region but absorb after the polymer is attached and the peak position is the same as CF ₃ -PPO. It can be seen that they adhere well to the carbon nanotubes.

6 shows gel permeation chromatography analysis of poly (3-trifluoromethylphenylene oxide) (CF ₃ -PPO) prepared in Comparative Example, showing a relatively narrow molecular weight distribution of PDI = 1.3 or less.

7A-7C show single-walled carbon nanotubes (SWNT-PPO, Example 2) attached to poly (3-trifluoromethylphenylene oxide), poly (3-trifluoromethylphenylene oxide) (CF ₃ − As a result of the differential scanning calorimetry of the 1:10 mixture of PPO, Comparative Example) and poly (3-trifluoromethylphenylene oxide) (CF ₃ -PPO) prepared in Comparative Example, CF ₃ -PPO was obtained. When attached to the carbon nanotubes, the crystallinity is smaller than in other cases, it can be seen that the melting temperature is lowered.

9 is a nuclear magnetic resonance spectroscopy spectrum according to the temperature of a single-walled carbon nanotube to which poly (arylene ether amide) is prepared according to Example 3 of the present invention, poly (3-trifluoromethylphenylene oxide) It can be seen that the spectrum is not sharp but wider as in the case of single-walled carbon nanotubes (SWNT-PPO) to which is attached.

10A is a scanning electron micrograph and an energy dispersive X-ray spectrum of CNT-I prepared in Example 1 of the present invention, in which single-wall carbon nanotubes substituted with an initiator are well dissolved and clearly show a fiber structure in SEM images. It can be seen. FIG. 10B is a scanning electron micrograph and energy dispersive X-ray spectrum of a single-walled carbon nanotube (SWNT-PPO) to which poly (3-trifluoromethylphenylene oxide) prepared in Example 2 of the present invention is attached. In the case of PPO, the fiber structure becomes invisible due to the adhesion of the polymer. In addition, it can be seen from the EDAX measurement that the carbon nanotubes surround the CF ₃ -PPO. 10c is a scanning electron micrograph and energy dispersive X-ray spectrum of a 1:10 mixture of carbon nanotubes and a poly (3-trifluoromethylphenylene oxide) (CF ₃ -PPO) prepared in Comparative Example, wherein the polymer and nanotubes You can see them separated as if they are stuck without being mixed.

FIG. 11A is a scanning electron micrograph and an energy dispersive X-ray spectrum of CNT-I prepared in Example 1 of the present invention, where single-walled carbon nanotubes substituted with an initiator are well dissolved and clearly show a fiber structure in SEM image. Can be.

FIG. 11B is a scanning electron micrograph and an energy dispersive X-ray spectrum of a single-walled carbon nanotube to which poly (arylene ether amide) is prepared according to Example 3 of the present invention. The fiber structure disappears as the polymer is attached. Able to know.

Claims (12)

Modified carbon nanotubes to which an initiator is attached, which can cause chain growth condensation polymerization represented by Chemical Formula 1 below.
[Formula 1]

[remind

silver

or

ego;
R is CF ₃ or CN;
X is F, Cl or NO ₂ ;
n is an integer of 1 or more and 10 to 10 carbon atoms of the carbon nanotube. 1 for every 100.] The method of claim 1,
remind

The modified carbon nanotube to which the initiator is attached, which is selected from the following structures.

The method of claim 1,
The modified carbon nanotubes are carbon nanotubes, characterized in that prepared by the reaction of the initiator precursor represented by the formula (2).
(2)

[Y is N ₂ BF ₄ or NH ₂ ;

silver

or

ego;
R is CF ₃ or CN;
X is F, Cl or NO ₂ ] The method of claim 3, wherein
The initiator precursor is modified carbon nanotubes, characterized in that at least one selected from the following compounds.

A composite carbon nanotube prepared by polymerization of a monomer forming a modified carbon nanotube and a poly (arylene ether) polymer of claim 1. 6. The method of claim 5,
The monomer is a composite carbon nanotube, characterized in that the monomer represented by the formula (3) or (5).
(3)

[Chemical Formula 5]

[

Is selected from the following structures;

X 'is F, Cl or NO ₂ ] The method according to claim 6,
The monomer selected from the following compounds. Composite carbon nanotubes, characterized in that at least one.

A method of preparing a composite carbon nanotube of Formula 4 by chain-growth condensation polymerization of a modified carbon nanotube to which an initiator represented by Formula 1 is attached and a monomer represented by Formula 3.
[Formula 1]

(3)

[Chemical Formula 4]

[Wherein,

silver

or

ego;
R is CF ₃ or CN;

Is selected from the following structures;

X 'is F, Cl or NO ₂ ;
m is an integer from 1 to 400; And
l is an integer equal to or less than n of CNT-I in Formula 1 of claim 1] A method of preparing a composite carbon nanotube by step-growth condensation polymerization of a monomer forming a modified carbon nanotube and a poly (arylene ether) -based polymer having an initiator attached to it according to Formula 1 below.
[Formula 1]

[remind

silver

or

ego;
R is CF ₃ or CN;
X is F, Cl or NO ₂ ;
n is an integer of 1 or more and 10 to 10 carbon atoms of the carbon nanotube. 1 for every 100.] The method of claim 9,
The poly (arylene ether) -based polymer is poly (ether sulfone), poly (ether ketone), poly (ether ether sulfone), poly (ether ether ketone), poly (ether imide), poly (arylene ether) and At least one selected from poly (arylene ether amide). The method of claim 9,
The monomer forming the poly (arylene ether) -based polymer is characterized in that represented by the formula (5).
[Chemical Formula 5]

[

Is selected from the following structures;

X 'is F, Cl or NO ₂ ] The method according to claim 8 or 9,
The polymerization solvent used in the polymerization is 1 selected from the group consisting of N-methylpyrrolidone, dimethyl sulfoxide, N, N-dimethylacetamide, N, N-dimethylformamide, diphenylsulfone and sulfolane. At least one polar aprotic solvent.

Images