KR102068895B1 - Cnt/polymer composite and method of preparing the same - Google Patents

Abstract

The present invention relates to a CNT / polymer composite and a method for manufacturing the same, the present invention is easy to mass production and extrusion molding, by modifying the CNT surface through a chemical treatment or physical method and bind the Regent, so that the Regent and polymer on the CNT surface It is possible to provide a CNT / polymer composite that exhibits excellent mechanical properties involved.

Description

CNT / POLYMER COMPOSITE AND METHOD OF PREPARING THE SAME}

The present invention relates to a CNT / polymer composite and a method for producing the same, and more particularly, to a CNT / polymer composite and a method for producing the same having improved mechanical properties.

Engineering plastic materials, including polyketone, nylon and polycarbonate, are widely used as industrial materials in various fields, such as automobile and aircraft bodywork, electromagnetic shielding parts. Since such engineering plastics, that is, polymer materials, exhibit excellent properties such as chemical resistance, abrasion resistance, and impact resistance, they are expected to be applied in various industries. However, there is a problem that low mechanical strength and electrical conductivity, which are generally found in polymer materials, remain limited. In order to improve this problem, polymer composites including glass fiber, carbon black and carbon fiber as fillers have been prepared, but in order to achieve the required physical properties, a large amount of filler is required, and when a large amount of filler is included, the viscosity during processing Increased and manufacturing cost increased. The higher the viscosity, the more difficult the extrusion and injection molding of the composite, the appearance is different, the increased manufacturing cost is difficult to use in various industries. In order to solve such a problem, another study was continued, but due to the difference in the structural properties between the polymer material and the filler, there was a problem in that the property improvement effect was limited due to the low interfacial adhesion.

One object of the present invention is to provide a composite and a method for producing the composite having excellent mechanical strength and easy mass production and extrusion molding by including Grignard Regent and a polymer on the surface of carbon nanotubes.

CNT / polymer composite for one purpose of the present invention is a carbon nanotube having a metal complex on the surface; And a polymer, wherein the carbon nanotube having the metal composite on the surface has a structure in which the metal complex is bonded to an organic compound disposed on the carbon nanotube surface.

In one embodiment, the organic compound disposed on the surface of the carbon nanotubes may be a substituted or unsubstituted alkyl group and an aromatic ring compound.

In one embodiment, the organic compound disposed on the surface of the carbon nanotube is a substituted or unsubstituted pyrene compound, and the carbon and the pyrene compound constituting the carbon nanotube are bonded by physical adsorption, and the pyrene compound The metal complex may be combined.

In one embodiment, the metal composite may include at least one of Mg and Li.

In one embodiment, the polymer may be at least one of polyketone, polycarbonate, polyester and nylon.

A method for producing a CNT / polymer composite for another object of the present invention includes a first step of adding a carbon nanotube and an organic compound to a first solvent and reacting to produce a modified carbon nanotube; And a second step of reaction extruding the carbon nanotubes and the polymer prepared in the first step.

In one embodiment, the organic compound may be pyrenyl butyllithium (PBuLi) and 1-pyrenemethyl bromide (PBr).

In one embodiment, after the first step, before the second step, the modified carbon nanotube and the metal compound prepared in the first step are added to the second solvent and reacted to include a pyrene and a metal halide compound. It may further comprise a; 1-2 step of preparing a carbon nanotube composite.

Method for producing a CNT / polymer composite for another object of the present invention is a step of preparing a carbon nanotube having a carboxylic acid by reacting the carbon nanotubes with an acid solution; B) preparing a surface-modified carbon nanotube by reacting the carbon nanotube having the carboxylic acid prepared in step a with a chlorine compound; C) preparing carbon nanotubes containing halogen by adding the surface-modified carbon nanotubes and a halogen compound to a first solvent and reacting them; Adding the carbon nanotube and the metal compound including the halogen to a second solvent and reacting to prepare a carbon nanotube composite having a metal halogen complex; And a step e of reacting and extruding the carbon nanotube composite and the polymer prepared in step d.

In step b, in the embodiment, the chlorine compound may be thionyl chloride (Thionyl Chloride) (SOCl ₂ ).

In one embodiment, in step c, the halogen compound may be 3-bromopropan-1-amine.

The present invention relates to a CNT / polymer composite and a method for manufacturing the same, the present invention is easy to mass production and extrusion molding, by modifying the CNT surface through a chemical treatment or physical method and bind the Regent, so that the Regent and polymer on the CNT surface It is possible to provide a CNT / polymer composite that exhibits excellent mechanical properties involved.

1 is a view schematically showing a part of the manufacturing method of the present invention.
2 and 3 are views showing a composite prepared according to one embodiment.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "having" are intended to indicate that there is a feature, step, operation, component, part, or combination thereof described on the specification, but one or more other features or steps. It is to be understood that the present invention does not exclude, in advance, the possibility of the addition or the presence of any operation, components, parts or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

CNT / polymer composite of the present invention is a carbon nanotube having a metal complex on the surface; And polymers. In one embodiment, the carbon nanotube having the metal complex on the surface may have a structure in which the metal complex is bonded to an organic compound disposed on the surface of the carbon nanotube.

In one embodiment, the carbon nanotubes forming the CNT / polymer composite of the present invention are in other words, an organic compound is disposed on the surface of the carbon nanotubes, and a metal compound, a metal complex, or a metal halogen complex is combined with the organic compound. , The organic compound may be bound to the surface of the carbon nanotubes through chemical treatment or physical adsorption.

In one embodiment, the CNT / polymer composite of the present invention may be formed by reacting carbon nanotubes and a polymer material including an organic compound and a metal compound on a surface thereof.

In one embodiment, the organic compound disposed on the surface of the carbon nanotubes may be a substituted or unsubstituted alkyl group and an aromatic ring compound. For example, the organic compound disposed on the surface of the carbon nanotube may be a substituted or unsubstituted pyrene compound.

In one embodiment, the CNT / polymer composite may be one in which carbon and pyrene compounds constituting carbon nanotubes are bonded by physical adsorption, and a metal complex is bonded to the pyrene compound. In one embodiment, a material such as pyrene may be physically adsorbed onto the carbon nanotubes through pi bond (π-bond, pi-bond) with the carbon sp ² structure of the carbon nanotubes.

In one embodiment, the metal complex may include a halogen compound, but is not limited thereto. For example, the metal complex may include Br (bromine).

In one embodiment, the metal composite may include a metal element, but is not limited thereto. For example, the metal composite may include at least one of Mg (magnesium, magnesium) and Li (lithium, lithium).

In one embodiment, the polymer is not limited thereto, but may be a polymer including a carbonyl functional group (C═O, carbonyl). For example, at least one of polyketone, polycarbonate, polyester, and nylon may be used.

In one embodiment, the CNT / polymer complex may include Grignard reagent. The Grignard Regent is a generic term for a compound of R-Mg-X type, R is an organic compound and X is a halogen. In one embodiment, the CNT / polymer composite of the present invention may have a structure in which R, which is an organic compound in a Grignard Reagent and an R-Mg-X structure, is bonded to a carbon nanotube surface.

The CNT / polymer composite of the present invention may be used as a polymer material having improved mechanical properties by including carbon nanotubes as a filler.

The method for producing a CNT / polymer composite of the present invention comprises the steps of adding a carbon nanotube and an organic compound to a first solvent and reacting to produce a modified carbon nanotube; And a second step of reaction extrusion of the prepared carbon nanotubes and the polymer. The CNT / polymer composite having improved mechanical properties may be prepared by the above manufacturing method, and the CNT / polymer composite thus prepared may be used in various fields as a polymer material. In particular, in the case of poly ketone was not active due to problems such as production process, it can be used as a composite material showing excellent physical properties in various fields such as vehicles, aircraft through the present invention.

In one embodiment, the polymer may be a variety of polymer materials, but is not limited thereto. For example, the polymer may be at least one of polyketone, polycarbonate, polyester, and nylon. have.

In one embodiment, the organic compound may be pyrenyl butyllithium (PBuLi). In one embodiment, carbon nanotubes and pyrenylbutyllithium are added to the first solvent and reacted to produce modified carbon nanotubes, and the carbon nanotubes and the polymer prepared above are reacted and extruded to produce the CNT / polymer of the present invention. Composites can be prepared.

In one embodiment, when pyrenylbutyllithium is used as the organic compound, the prepared CNT / polymer composite may include lithium.

In one embodiment, the organic compound may be 1-pyrenemethyl bromide (PBr).

In one embodiment, after the first step, before the second step, the modified carbon nanotube and the metal compound prepared in the first step are added to the second solvent and reacted to include a pyrene and a metal halide compound. It may further comprise a; 1-2 step of manufacturing the carbon nanotubes.

In other words, in one embodiment, a first step of preparing a modified carbon nanotube by adding and reacting carbon nanotubes and 1-pyrenemethylbromide to a first solvent; After the first step, the modified carbon nanotube and the metal compound prepared in the first step is added to the second solvent and reacted to prepare a carbon nanotube composite including a pyrene and a metal halogen compound 1- After performing step 2, the CNT / polymer composite of the present invention may be prepared through the second step of reaction extrusion by mixing the carbon nanotubes and the polymer prepared in step 1-2 at a predetermined ratio.

1 is a view schematically showing a part of the manufacturing method of the present invention. Figure 1 schematically shows a part of the process for preparing the CNT / polymer composite of the present invention using Grignard Regent. In an embodiment, the carbon nanotubes are surface-modified to prepare carbon nanotubes into which an organic compound having Br is introduced, and thereafter, magnesium is added to the surface of the carbon nanotubes, where R-MgBr (Grignard Regent) is introduced. It shows that the tube is manufactured. As such, when the carbon nanotubes into which R-MgBr is introduced are reacted and extruded by mixing a predetermined ratio with a polymer, for example, polyketone, the CNT / polymer composite of the present invention may be prepared.

In one embodiment, the metal compound may include Mg in the first and second steps. For example, Grignard Regent may be included on the surface of the carbon nanotubes through the first and second steps.

In one embodiment, the first solvent and the second solvent may be independently tetrahydrofuran (THF), anhydrous tetrahydrofuran, and mixtures thereof.

Another CNT / polymer composite production method of the present invention is a step of preparing a carbon nanotube having a carboxylic acid by reacting the carbon nanotubes with an acid solution; B) preparing a surface-modified carbon nanotube by reacting the carbon nanotube having the carboxylic acid prepared in step a with a chlorine compound; C) preparing carbon nanotubes containing halogen by adding the surface-modified carbon nanotubes and a halogen compound to a first solvent and reacting them; Adding the halogenated carbon nanotube and the metal compound to a second solvent and reacting to prepare a carbon nanotube composite having a metal halogen complex; And a step e of reacting and extruding the carbon nanotube composite and the polymer prepared in step d.

In an embodiment, in step a, the acid solution may include at least one of phosphoric acid, sulfuric acid, and nitric acid. If the acid strength is too strong, the carbon nanotube structure may be destroyed, and if the acid strength is too weak, the carbon nanotubes may not sufficiently react. For example, the acid solution may have a ratio of sulfuric acid and nitric acid 3: 2.

In one embodiment, the step b is a step of producing a surface-modified carbon nanotubes by reacting the carbon nanotubes having the carboxylic acid prepared in step a with a chlorine compound, for example, the surface formed through step b The modified carbon nanotubes may be carbon nanotubes into which acyl chloride end groups are introduced. In one embodiment, in step b, the chlorine compound may be, but not limited to, thionyl chloride (SOCl ₂ ).

In one embodiment, the step c is adding the surface-modified carbon nanotubes and the halogen compound to a first solvent and reacting to prepare carbon nanotubes containing halogen, for example, halogen formed through step c. Carbon nanotubes containing may be an acyl chloride group is substituted with a halogen. As an example, carbon nanotubes into which Br groups are introduced may be formed. In one embodiment, in step c, the halogen compound may be, but is not limited to, 3-bromopropan-1-amine (3-bromopropan-1-amine).

In one embodiment, the step d is a step of adding a carbon nanotube and a metal compound containing the halogen to the second solvent and reacting to prepare a carbon nanotube composite having a metal halogen complex, in one embodiment the d In the step, the metal compound may include Mg. For example, the carbon nanotube composite into which Grignard Regent is introduced may be prepared through step d. For example, the carbon nanotube composite having the metal halogen complex formed through step d may be a carbon nanotube having MgBr.

In one embodiment, the first solvent and the second solvent may be, but are not limited to, tetrahydrofuran (THF), anhydrous tetrahydrofuran, and a mixture thereof.

In one embodiment, the step e is a step of reaction extrusion of the carbon nanotube composite and the polymer prepared in step d, for example, a carbon nanotube and a polymer material having MgBr, such as 1: 100 or 3: 100 The CNT / polymer composite of the present invention may be prepared by reaction extrusion by mixing at a ratio. When the ratio of the carbon nanotubes is 0.5 or less, the polymer may not have an effect of improving mechanical properties. When the ratio of the carbon nanotubes is 5 or more, the impact resistance of the polymer material may decrease. Can be.

In one embodiment, the polymer is not limited thereto, but may be at least one of polyketone, polycarbonate, polyester, and nylon.

Composite materials in which nano-sized fillers are added to polymers can improve mechanical and electrical properties in much smaller amounts than when micro-sized fillers are introduced. As a filler, carbon nanotubes can exhibit excellent mechanical properties compared to other nano-sized materials. Since carbon nanotubes have a fiber-like structure, the carbon nanotubes can greatly contribute to improving mechanical properties of the polymer composite. However, when carbon nanotubes are added to the polymer material, agglomeration may occur due to physical attraction and entanglement between the carbon nanotubes, and since the polymer material and the carbon nanotubes have different structural properties, they exhibit low interfacial adhesion, thereby improving physical properties. The effect may be limited. However, in the case of the present invention, since the polymer is polymerized on the carbon nanotubes by modifying the surface of the carbon nanotubes through chemical or physical methods, excellent physical properties can be exhibited. As a result, it can be seen that maximization of the interfacial adhesion between the polymer material and the carbon nanobute and the improvement of the dispersibility have been achieved.

In the case of the chemical treatment method as an embodiment of the present invention is suitable for the melt kneading method, the chain entanglement between the polymer matrix and the carbon nanotubes polymerized on the surface can be induced to improve mechanical properties have.

In the case of a physical method as in an embodiment of the present invention, Grignard Regent and the like may be used. Grignard Regent is a highly reactive reagent that has excellent reactivity with materials containing carbonyl functional groups (C═O) such as ketones, amides and esters. Therefore, when Grignard Regent is bonded to carbon nanotubes, it can be easily reacted and polymerized with various polymers such as polyketone, nylon, polycarbonate, and polyester. As described above, when the CNT / polymer composite is formed by a physical method, there is no need to treat an acid solution or ozone, so that it is more stable, the manufacturing process is easy, and there is an advantage that a problem such as environmental pollution is less likely to occur.

Example 1

According to one embodiment of the present invention, a surface modified CNT (Example 1) having a functional group introduced therein was prepared using a chemical treatment method.

First, 1 g of multi-walled carbon nanotube (pristine MWCNT) is dispersed in 100 ml of a mixture of sulfuric acid and nitric acid (mass ratio of sulfuric acid: nitric acid = 3: 2), and then reacted at 60 ° C. for 24 hours, and the resulting material is decompressed. Recovered by filtration. After washing with distilled water and dried for 24 hours in a vacuum oven at 80 ℃ to completely remove the residual moisture. Through this process, a carbon nanotube into which a carboxylic acid group (Carboxyl acid, -COOH) was introduced was obtained. Carbon nanotubes into which the carboxylic acid group thus prepared was introduced are referred to as MWCNT-COOH.

Then, 1 g of MWCNT-COOH prepared was dispersed in 200 ml of thionyl chloride (SOCl ₂ ) and reacted at 70 ° C. for 24 hours to prepare carbon nanotubes having acyl chloride groups introduced therein. After filtration under reduced pressure, the reacted carbon nanotubes were recovered and washed with tetrahydrofuran (THF). It was then dried in a vacuum oven at 80 ° C. for 24 hours. The carbon nanotubes into which the acyl chloride group thus prepared were introduced are referred to as surface modified CNTs (MWCNT-COCl, Example 1).

Example 2

Regent-bound CNTs (Example 2) were prepared using chemically surface modified CNTs (Example 1) according to one embodiment of the present invention.

1 g of surface-modified CNT (MWCNT-COCl) prepared in Example 1 was dispersed in 500 ml of THF, and then 5 g of 3-bromopropan-1-amine was added to room temperature. 25 ° C.) for 24 hours. In this process, all or part of the acyl chloride group of the carbon nanotube may be substituted with Br group. Thereafter, unreacted 3-bromo propane-1-amine and THF were removed using reduced pressure filtration, and dried in a vacuum oven at 80 ° C. for 24 hours to obtain a Br group-introduced carbon nanotube. Br-introduced carbon nanotubes thus prepared are referred to as MWCNT-Br.

Then, in order to bind Grignard Regent to the surface of MWCNT-Br, 1 g of MWCNT-Br was dispersed in 500 ml of anhydrous THF, and 1 g of Mg was added thereto, followed by stirring at room temperature (25 ° C.) for 1 hour. After stirring, THF and residual Mg were removed using reduced pressure filtration. Reagent-coupled carbon nanotubes, MWCNT-MgBr (Example 2) through the chemical treatment thus prepared was kept sealed in a state filled with nitrogen. Example 2 also proceeded while maintaining a nitrogen gas flow therein to avoid contact with moisture.

Example 3

Regent-bound CNTs (Example 3) were prepared using a physical treatment method in accordance with one embodiment of the present invention.

1 g of MWCNT and 0.5 g of 1-pyrenemethyl bromide (PBr) were dispersed in 500 ml of THF for 30 minutes. In this process, PBr was physically adsorbed on the surface of MWCNT by pi-pi interaction. After dispersion, PBr and THF that were not adsorbed on the surface of the MWCNT were removed by vacuum filtration, and dried in a vacuum oven at 80 ° C. for 24 hours to completely remove residual THF. Carbon nanotubes modified with PBr thus prepared are hereinafter referred to as MWCNT-PBr.

Then, 1 g of MWCNT-PBr prepared was dispersed in anhydrous THF, and then 1 g of Mg was added thereto, followed by stirring at room temperature (25 ° C.) for 1 hour. In this process, PBr adsorbed on the surface of MWCNT is substituted with 1-pyenemethyl magnesium bromide (PMgBr), and THF and residual Mg were removed by vacuum filtration after stirring. Carbon nanotubes containing PMgBr thus prepared are hereinafter referred to as MWCNT-PMgBr. In addition, Example 3 was carried out under a nitrogen atmosphere to avoid contact with moisture, and the MWCNT-PMgBr was stored in a sealed state with nitrogen.

Example 4

MWCNT-MgBr prepared in Example 2 and polyketone were reacted and extruded to prepare a CNT / polymer composite (Example 4).

The feed, melt and mix temperatures of the twin screw extruder used for the reaction extrusion were maintained at 235, 250 and 250 ° C., respectively, and the feed ratio of polyketone and MWCNT-MgBr was set at 100: 1 to feed and extruded the twin screw extruder. . Then, the extruded material (1 g) was dissolved in 1-hexafluoroisopropanol (HFIP), which is a solvent of polyketone, and then unreacted polyketone was removed using a centrifuge. The above process was repeated five times to completely remove the unreacted polyketone, thereby obtaining carbon nanotubes polymerized with polyketone, that is, CNT / polymer composite and PK / MWCNT-MgBr (Example 4).

PK / MWCNT-MgBr-3 (Example 7) was prepared by setting only the weight ratio of polyketone and MWCNT-MgBr to 100: 3 in the same manner.

Example 5

By using MWCNT-PMgBr prepared in Example 3 instead of MWCNT-MgBr prepared in Example 2 by the reaction extrusion by setting the weight ratio of poly ketone and MWCNT-PMgBr to 100: 1 CNT / polymer composite, PK / MWCNT-PMgBr (Example 5) was prepared.

In the same manner, PK / MWCNT-PMgBr-3 (Example 8) was prepared by setting only the weight ratio of polyketone and MWCNT-PMgBr to 100: 3.

Example 6

By using the original MWCNT (pristine MWCNT) instead of MWCNT-MgBr prepared in Example 2 in the same manner as in Example 4 by setting the weight ratio of the poly ketone and the original MWCNT to 100: 1 PK / MWCNT (Example 6) was prepared.

PK / MWCNT-3 (Example 9) was prepared by setting only the weight ratio of polyketone and MWCNT to 100: 3 in the same manner.

Example 10

CNT / polymer composites (Examples 10, 11 and 12) were prepared using original MWCNTs and MWCNT-MgBr and MWCNT-PMgBr prepared in Examples 2 and 3, respectively, and nylon.

First, with respect to pristine MWCNT and MWCNT-MgBr and MWCNT-PMgBr prepared in Examples 2 and 3, the weight ratio of nylon 6,6 was 100 (nylon 6,6: carbon nanotube = 100: 1) CNT / Nylon 6,6 (PA66) complexes PA66 / MWCNT (Example 10), PA66 / MWCNT-MgBr (Example 11) and PA66 / MWCNT-PMgBr (Example 12) were prepared.

Example 13

In the same manner as in the physical method of adsorbing PBr on the surface of MWCNT in Example 3, carbon nanotubes, MWCNT-PBuLi (PBuLi) adsorbed on the surface of MWCNT and functionalized with butyllithium reagent (Example 13 ) Was prepared.

Then, a CNT / polymer composite, PK / MWCNT-PBuLi (Example 14), was prepared using a weight ratio of polyketone to 100 (polyketone: carbon nanotube = 100: 1) based on the MWCNT-PBuLi thus prepared.

Rating 1

2 is a view showing a composite prepared according to one embodiment. The shape of PK / MWCNT-MgBr from which the unreacted polyketone prepared in Example 4 was removed was observed by scanning electron microscope and transmission electron microscope to determine whether the polyketone was polymerized on the surface of carbon nanotubes. 2, the diameter of PK / MWCNT-MgBr (b) was larger than that of the original MWCNT (a). As a result of observing with a transmission electron microscope, the polymer layer was confirmed in MWCNT-PK. This shows that the polyketone was normally polymerized on the surface of the carbon nanotubes.

Evaluation 2

The mechanical properties of the composites prepared in Examples 4, 5 and 6 were compared. To compare the mechanical properties, first, composite tensile specimens of Examples 4, 5, and 6 were prepared using an injection molding machine according to ASTM D 638 at 250 ° C. In addition, tensile specimens of polyketone (neat PK) (pure polyketone) containing no carbon nanotubes were also injection-molded for comparison, and their tensile strength, tensile modulus and tensile elongation were measured and shown in Table 1 below.

Table 1 shows below, in the case of a composite including carbon nanotubes containing Grignard Regent when the content of carbon nanotubes in the composite is the same (Examples 4 and 5), the composite using the original MWCNT (PK / MWCNT) it can be seen that the improved mechanical properties. In addition, when manufactured by bonding Grignard Regent to carbon nanotubes by using a physical method, that is, by using physical adsorption, that is, compared to Example 4 (PK / MWCNT-MgBr) prepared through a chemical treatment method, for example, Example 5 (PK / MWCNT-PMgBr) showed a more improved mechanical properties. This is believed to be due to the improvement of interfacial adhesion and dispersibility as the Grignard Reagent is bonded and the polyketone is polymerized without destroying the carbon nanotube structure by using the physical adsorption method.

Pure PK PK / MWCNT
(Example 6) PK / MWCNT-MgBr
(Example 4) PK / MWCNT-PMgBr
(Example 5) Tensile Strength (MPa) 56.0 59.8 65.4 67.1 Tensile Modulus (MPa) 728.8 795.0 895.9 937.0 Tensile Elongation (%) 426.8 94.7 112.4 125.1

Evaluation 3

Tensile strength, tensile modulus and tensile elongation of Examples 7, 8 and 9 in which the weight ratio of polyketone and CNT material were 100: 3 in the same manner as in Evaluation 2 were measured and shown in Table 2.

Pure PK PK / MWCNT-3
(Example 9) PK / MWCNT-MgBr-3
(Example 7) PK / MWCNT-PMgBr-3
(Example 8) Tensile Strength (MPa) 56.0 63.2 72.7 74.4 Tensile Modulus (MPa) 728.8 839.3 985.4 1045.6 Tensile Elongation (%) 426.8 41.5 61.3 71.0

Evaluation 4

The electrical conductivity of the composites prepared in Examples 4, 5 and 6 was measured. In order to measure the electrical conductivity, a composite film having a thickness of 1 mm was formed by compression molding the composite and the polyketone prepared according to Examples 4, 5 and 6 at 250 ° C.

The conductivity of polyketone (PK) was 2.6X10 ^-15 S / cm, whereas the PK / MWCNT composite (Example 6) showed 4.3X10 ^-8 S / cm. The PK / MWCNT-MgBr complex (Example 4) and PK / MWCNT-PMgBr complex (Example 5) showed more improved electrical conductivity at 7.2X10 ^-8 S / cm and 8.5X10 ^-8 S / cm, respectively. , PK / MWCNT-PMgBr showed the best electrical conductivity compared to the same content among the composites.

Evaluation 5

The interfacial properties of the prepared composites were confirmed through the examples. 3 is a view showing a composite prepared according to one embodiment, the fracture surface of the tensile specimens of Examples 4 and 6 using a scanning electron microscope is shown in FIG. As shown in FIG. 3, in the case of the PK / MWCNT composite (Example 6), (a) a breakage between the polyketone matrix and the carbon nanotube was formed to form an empty space, which is a polyketone without surface modification or regent bonding. This means that the interfacial adhesion between MWCNT and MWCNT is not good. On the other hand, in the case of the PK / MWCNT-MgBr composite (Example 4), it could be seen that (b) the fracture between the polyketone matrix and the carbon nanotubes was not broken, and the diameter of the carbon nanotubes was increased. This indicates that the polyketone was normally polymerized on the surface of the carbon nanotubes, and the interfacial adhesion between the polyketones and the carbon nanotubes was improved.

Evaluation 6

Tensile specimens were prepared by injection molding CNT / nylon 6,6 (PA66) composites of Examples 10, 11 and 12, respectively. And using this to measure the respective mechanical properties are shown in Table 3. Also in this case, the PA66 / MWCNT-PMgBr composite (Example 12) showed the best mechanical properties.

Pure PA66 PK / MWCNT
(Example 10) PK / MWCNT-MgBr
(Example 11) PK / MWCNT-PMgBr
(Example 12) Tensile Strength (MPa) 63.1 68.4 76.8 78.5 Tensile Modulus (MPa) 1620.4 1704.7 1894.0 1930.6 Tensile Elongation (%) 120.5 28.4 35.7 38.0

Evaluation 7

The mechanical properties of the CNT / polymer composite prepared according to Example 14 and PK / MWCNT-PBuLi were measured and shown in Table 4 below. Example 14 was also confirmed to exhibit improved mechanical properties. However, mechanical properties were somewhat lower than those of the same ratio of PK / MWCNT-PMgBr composite (Example 8).

Pure PK PK / MWCNT
(Example 6) PK / MWCNT-PBuLi
(Example 14) PK / MWCNT-PMgBr
(Example 5) Tensile Strength (MPa) 56.0 59.8 65.9 67.1 Tensile Modulus (MPa) 728.8 795.0 904.2 937.0 Tensile Elongation (%) 426.8 94.7 117.5 125.1

According to an embodiment of the present invention, even if the modified carbon nanotubes are reacted with a polymer material through chemical treatment, mechanical properties may be improved, but pyrene may be obtained through carbon sp ² structure of carbon nanotubes and carbon through pi bond. The CNT / polymer composites which can be physically adsorbed to the nanotubes and formed by this physical adsorption method can prevent deformation or destruction of the structure of the CNTs compared to the CNT / polymer composites formed by chemical treatment, and thus mechanical properties The improvement effect may be even better.

While the foregoing has been described with reference to preferred embodiments of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. Will understand.

Claims (12)

delete delete delete delete delete Adding a carbon nanotube and an organic compound to a first solvent and reacting to prepare a modified carbon nanotube; And
And a second step of reaction extruding the carbon nanotubes and the polymer prepared in the first step.
In the first step, the organic compound is characterized in that at least one or more of pyrenyl butyllithium (PBuLi) and 1-pyrenemethyl bromide (PBr),
Method for preparing CNT / polymer composite.
delete The method of claim 6,
After the first step, before the second step,
Further comprising the step 1-2 of preparing a carbon nanotube comprising a pyrene and a metal halogen compound by adding and reacting the modified carbon nanotube and the metal compound prepared in the first step in a second solvent;
Method for preparing CNT / polymer composite.
Reacting the carbon nanotubes with an acid solution to prepare carbon nanotubes having carboxylic acid;
B) preparing a surface-modified carbon nanotube by reacting the carbon nanotube having the carboxylic acid prepared in step a with a chlorine compound;
C) preparing carbon nanotubes containing halogen by adding the surface-modified carbon nanotubes and a halogen compound to a first solvent and reacting them;
Adding the halogenated carbon nanotube and the metal compound to a second solvent and reacting to prepare a carbon nanotube composite having a metal halogen complex; And
E; reacting and extruding the carbon nanotube composite and the polymer prepared in step d;
Method for preparing CNT / polymer composite.
The method of claim 9,
In step b, the chlorine compound is characterized in that the thionyl chloride (Thionyl Chloride) (SOCl ₂ ),
Method for preparing CNT / polymer composite.
The method of claim 10,
In step c, the halogen compound is characterized in that 3-bromopropan-1-amine (3-bromopropan-1-amine),
Method for preparing CNT / polymer composite. A CNT / polymer composite prepared according to the method of any one of claims 6 and 8-11.

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