KR100879755B1 - Method for preparing polycarbonate spherical particles and polycarbonate/carbon nanotube composite particles - Google Patents

Abstract

A method for preparing polycarbonate/carbon nanotube composite particles is provided to obtain the sphere polycarbonate/carbon nanotube composite particles having uniform-size and to improve the mechanical and electric properties. A method for preparing the polycarbonate/carbon nanotube composite particles comprises (S1) a step for dispersing carbon nanotube in the water phase including a stabilizer; and (S2) a step for manufacturing the polycarbonate/carbon nanotube composite particles from the emulsion obtained by mixing the water phase dispersed with carbon nanotube and the organic phase dissolved with polycarbonate homogeneously.

Description

Methods for preparing polycarbonate spherical particles and polycarbonate / carbon nanotube composite particles {Method for preparing polycarbonate spherical particles and polycarbonate / carbon nanotube composite particles}

The present invention relates to a method for producing spherical polycarbonate particles and spherical polycarbonate / carbon nanotube composite particles in which carbon nanotubes are selectively introduced into the surface and inside of the particles. More specifically, a two-phase solution of an aqueous phase and an organic phase is prepared in an emulsion state using a homogenizer. At this time, the polycarbonate of the organic phase is stable by polyvinylpyrrolidone, an interfacial stabilizer dissolved in the aqueous phase. It exists in the form of a micro emulsion. The prepared emulsion is obtained as spherical polycarbonate particles by removing the organic solvent through a washing and drying process. In addition, the present invention by dispersing the carbon nanotubes in the organic phase or the aqueous solution during the manufacturing process of the polycarbonate particles to the polycarbonate / carbon nanotube composite particles where carbon nanotubes are selectively introduced on the surface or inside of the spherical polycarbonate It can be produced.

Spherical particles according to the present invention are prepared through a phase separation method using a homogenizer. The method for producing particles using phase separation is simple and fast, and has the advantage of being applicable to polymers such as polycarbonate which cannot be produced in the form of spherical particles during the polymerization process.

Polycarbonate is the first polymer resin produced by Bayer, Germany, in 1956, and is generally a polycarbonate ester produced by the reaction of bisphenol A and phosgene. Polycarbonate is a kind of engineering plastic, and has high transparency, heat stability, and mechanical strength (tensile strength of 820 Kg / ㎠, impact value 900 cm / ㎠). Polycarbonate resins, which are currently produced on an industrial scale, are produced by the solvent method, which reacts bisphenol A with carbonyl chloride in the presence of an oxygen binder and a solvent to produce a polycarbonate. Pyridine or caustic alkali is used as the oxygen binder, and methylene chloride, chlorobenzene, xylene and the like are used as the solvent. In addition, a third amine such as triethylamine or a salt thereof is added to accelerate the polycondensation reaction, and a terminator such as t-butylphenol is used to control the average molecular weight. In addition, small amounts of antioxidants such as hydrosulfide are added. Reaction is normally performed at the temperature of 20-30 degreeC. When carbonyl chloride is blown in, a low molecular weight polymer having an end group such as -CCOCl in the solvent is obtained. When it is mixed vigorously for a long time while being in contact with alkali, the low molecular weight produced first is gradually condensation-polymerized into a polycarbonate of a polymer and eventually becomes a dope or granular form.

Polycarbonate is used in silicone coatings for wear resistant coatings, impact reinforcement alternative windows, banks, embassies, prison guard windows, military aircraft or bus windows that require abrasion resistance, billboards and vending machines. In addition, it is mixed with ABS, polyester (PBT or PET), styrene maleic anhydride (SMA), modified polyphenylene oxide (MPPO), etc., to provide impact resistance, heat resistance and low temperature flexibility, such as lighting systems, instrument panels and components of automobiles. It is used for interior and exterior materials of automobiles which are required. In particular, as a material for automobile bumpers, Xenoy (polycarbonate / PBT) of GE plastics, Vandal of Hoechst Celanese, and Makroblend of Bayer Polycarbonate / PET) and Dow's SABRE (Polycarbonate / PET) dominate the market. It is also used as a housing and cover of household appliances / tools that require heat resistance, electrical insulation, impact resistance, strength, and transparency, and connectors of fiber-optic cable lines. It can also be used as a membrane switch.

Forecasts of future prospects for polycarbonate are expected to grow at 10 percent annually, with new applications, materials development and molding processing technologies being key to high value added resins. In the manufacture of various grades of polycarbonate, researches to actively compensate for the shortcomings through the change of the end group or structure have been actively conducted. As the end group, phenol group and p-tert-butylphenol group are mainly used, but cumyl phenol is also used (GE Plastics). Since the end groups react almost completely, these polycarbonates have better thermal stability than other commercial polycarbonates. Have In addition, halogen end groups for increasing UV stability, fatty acid end groups for improving mold release properties, and the like have been studied. In order to compensate for the shortcomings through the change of structure, the research is mainly performed by changing the structure of bisphenol, which is to replace isopropylidine of bisphenol with small hydrocarbons and polar groups or methyl group or polar group instead of hydrogen of bisphenol. There is a method of substituting some or all of the substitutable positions. In addition, low-cost general-purpose resins such as polystyrene (PS), polymethyl methacrylate (PMMA), styrene acrylonitrile (SAN), and styrene maleic anhydride (SMA) are mixed with polycarbonate to increase moldability and lower prices. Efforts are being made a lot. Among the polymer composite materials currently commercialized, tetramethyl bisphenol-A polycarbonate (TMPC), tetrabromo polycarbonate (TBPC), tetrachloro polycarhonate (TCPC), etc. This flame retardant polycarbonate is used.

In Korean Patent Laid-Open Publication No. 2006-0007723, carbon nanotubes are added when melt kneading a mixture of polycarbonate and polystyrene or styrene-based copolymer to enhance compatibility between different polymers, thereby making the phase structure stable and excellent in mechanical performance. An invention is described relating to an improved polycarbonate / styrene-based copolymer resin composition. This improves the mechanical properties of the composite when carbon nanotubes are compounded inside the polymer matrix. However, a technique for introducing carbon nanotubes selectively on the surface or inside of the polymer matrix is not described.

In Korean Unexamined Patent Publication No. 195-0005885, an invention relating to a polycarbonate granule and a method for manufacturing the same is preceded. In order to prepare a polycarbonate granule having better dryness than the conventional recovery method, a polymer granule was prepared by stirring the polycarbonate solution under an organic solvent. However, since it is a manufacturing method using a low stirring speed in the organic phase rather than the two phase (phase), there is a disadvantage that the size is not uniform because irregular aggregates of several mm unit due to the aggregation phenomenon between the granules.

However, there have been no studies on the technology of forming and processing polycarbonate having spherical particles having a uniform micron size. The reason is that unlike polystyrene and polymethyl methacrylate, which are polymerized into particles through emulsion polymerization, dispersion polymerization, and suspension polymerization, polycarbonate is polymerized in a dope phase as described above. This is because it is not easy to process in the form of particles.

Spherical particulate polymers can be used for many purposes. For example, Jianfen. J. et al. Have reported using polystyrene particles in polysulfide matrix as reinforcing agents (J. Mater. Sci. 1999, 34, 4719). Cross-linked polystyrene particles of uniform size were prepared and mixed as a reinforcement on a polysulfide continuous phase to produce a composite film. At this time, when polystyrene particles of a certain concentration or more are added to the composite film, the particles are densely formed to form a network structure, and based on such a structure, the mechanical properties of the composite film manufactured by acting as a physical crosslinking in the composite film can be improved. .

Since carbon nanotubes were first discovered by Iijima in 1991, carbon nanotubes have been one of the major research areas due to their unique structure and excellent mechanical and electrical properties. Carbon nanotubes have been found in theoretical and experimental studies to have very high Young's modulus of about 1000 GPa, similar to graphite in-plane. Therefore, carbon nanotube-added polymer composites have high strength and low weight properties and have been known to be applicable to military and aviation materials due to these characteristics. In addition to mechanical properties, carbon nanotubes, another outstanding property of electrical properties, can be used to impart electrical conductivity to non-conductive polymers, which has the advantage of improving the electromagnetic shielding effect. Due to such excellent properties of carbon nanotubes, many efforts are being made to further improve the mechanical and electrical properties of existing polymers by manufacturing composite materials with various polymers.

An object of the present invention is to prepare a microemulsion, and to provide a method for producing spherical polycarbonate particles and polycarbonate / carbon nanotube composite particles of uniform size therefrom.

To this end, in the present invention, a two-phase solution of an aqueous phase and an organic phase is made into a stable emulsion using a homogenizer, and then polycarbonate spherical particles are prepared by washing and drying, and dispersing carbon nanotubes in an aqueous phase or an organic phase. Polycarbonate / carbon nanotube composite particles are prepared by selectively introducing carbon nanotubes on the surface or inside of spherical polycarbonate particles.

The micrometer-sized polycarbonate particles prepared in the present invention not only have a spherical shape but also have a uniform size, and can play various roles such as reinforcing agents or fillers of a polymer composite material based on the excellent physical properties of polycarbonate. In addition, by selectively introducing carbon nanotubes into or on the surface of polycarbonate particles, mechanical and electrical properties of the resulting polycarbonate / carbon nanotube composite particles may be improved.

According to a preferred embodiment of the present invention, there is provided a method for producing micro-sized spherical polycarbonate particles by phase separation from an emulsion formed by homogeneously mixing an aqueous phase comprising a stabilizer and an organic phase in which polycarbonate is dissolved.

According to another suitable embodiment of the present invention, the size of the spherical polycarbonate particles is characterized in that 0.5 ~ 3㎛.

According to another suitable embodiment of the present invention, the step of preparing the spherical polycarbonate / carbon nanotube composite particles by phase separation from an emulsion formed by homogeneously mixing the aqueous phase containing the stabilizer and the organic phase in which the polycarbonate is dissolved It includes, wherein the carbon nanotubes provide a method for producing spherical polycarbonate / carbon nanotube composite particles, characterized in that dispersed in an aqueous phase or an organic phase.

According to another suitable embodiment of the present invention, the carbon nanotubes are dispersed in an aqueous solution by acid treatment with nitric acid or sulfuric acid.

According to another suitable embodiment of the present invention, the carbon nanotubes are dispersed in an organic phase by introducing an alkyl group using a metal catalyst and an alkyl halide.

According to another suitable embodiment of the invention, the carbon nanotubes are located inside or on the surface of the spherical polycarbonate particles, the size is 0.5 ~ 3㎛, the electrical conductivity is 7.19x10 ^-13 ~ 5.1x10 ^-2 S / cm It provides a spherical polycarbonate / carbon nanotube composite particles characterized in that.

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

1 is a schematic diagram showing a method for producing spherical polycarbonate particles, comprising: (A) preparing an aqueous phase in which a stabilizer is dissolved and an organic phase in which polycarbonate is dissolved in an organic solvent; (B) preparing a stable emulsion using a homogenizer in a two-phase solution of an aqueous phase and an organic phase in a ratio of 9: 1 (volume ratio); (C) obtaining spherical polycarbonate particles by washing and drying the prepared emulsion.

Figure 2 is a schematic diagram of a manufacturing method showing a method of introducing carbon nanotubes on the surface of the spherical polycarbonate particles, (A) preparing an aqueous phase in which a stabilizer is dissolved and an organic phase in which polycarbonate is dissolved in an organic solvent; (B) acid treating the carbon nanotubes with strong acids of nitric acid and sulfuric acid; (C) dispersing the acid treated carbon nanotubes in an aqueous solution using a stabilizer; (C) preparing the prepared aqueous phase and the organic phase into a stable emulsion using a homogenizer in a ratio of 9: 1; (D) obtaining spherical polycarbonate composite particles in which carbon nanotubes are introduced to the particle surface by washing and drying the prepared emulsion.

3 is a schematic diagram of a manufacturing method for introducing carbon nanotubes into spherical polycarbonate particles, the method comprising the steps of: (A) preparing an aqueous phase in which a stabilizer is dissolved; (B) introducing an alkyl group to the carbon nanotubes using a metal catalyst and an alkyl halide; (C) dispersing the carbon nanotubes into which the alkyl group is introduced in an organic solvent (organic phase) in which polycarbonate is dissolved; (D) making the prepared aqueous phase and the organic phase a stable emulsion using a homogenizer in a ratio of 9: 1; (F) obtaining spherical polycarbonate composite particles having carbon nanotubes introduced therein through washing and drying the prepared emulsion.

In the emulsion prepared according to the above 1 to 3, it is preferable that the ratio of the aqueous phase and the organic phase is 80:20 ~ 95: 5.

As a stabilizer, an emulsion stabilizer and a polymer such as polyvinylpyrrolidone are used as a stabilizer for dispersing carbon nanotubes in an aqueous solution. In the present invention, polyvinylpyrrolidone, which is commonly used as an emulsion stabilizer for emulsion polymerization and is widely used as an aqueous phase dispersant for carbon nanotubes, is used as a stabilizer, and 3 to 6 wt% is contained in the aqueous phase. According to the present invention, various kinds of polymer stabilizers such as polyvinyl alcohol can be used.

As the organic solvent, organic solvents such as methylene chloride, chloroform and chlorobenzene, as well as solvents such as dioxane and tetrahydrofuran may be used, and these may be used alone or in mixture. In the present invention, methylene chloride is preferably used. Methylene chloride is a typical solvent of polycarbonate, and has a low miscibility with water, making it easy to form a polycarbonate emulsion.

The content of the carbon nanotubes contained in the emulsion prepared according to the present invention is preferably 0.01 to 0.05 wt%. This is the content of carbon nanotubes, which are expected to improve the physical properties of the polycarbonate / carbon nanotube composite particles finally produced dispersibility problems of carbon nanotubes.

The organic phase comprises 3-6 wt% polycarbonate in methylene chloride continuous phase.

As a pretreatment process of carbon nanotubes, an acid treatment is carried out by the following method to disperse in an aqueous solution. To remove impurities in carbon nanotubes such as metal catalysts and introduce carboxyl groups, the mixture was treated at 60 ^° C. in a 3: 1 mixed solution of nitric acid and sulfuric acid for 12 hours and dispersed in an organic phase. MWCNT) introduces dodecyl groups on the surface of multi-walled carbon nanotubes by reacting dodecyl sulfate with carbon nanotubes under an ammonium and magnesium catalyst. The purity of the acid-treated MWCNT was measured with a thermogravimetric analyzer and found to be 99% or higher.

In order to disperse the organic phase, a metal catalyst and an alkyl halide are used to introduce an alkyl group into the carbon nanotubes. Methods of introducing alkyl groups are described in F. Liang et. al. Adopted the method reported in 2004. First, 20 mg of multi-walled carbon nanotubes are prepared in a three-neck round-bottom flask, and 60 mL of NH ₃ is added thereto. To this was added 231 mg of lithium metal fragment, 6.4 mmol of alkyl iodide and then evaporated slowly for 12 hours while stirring. At the end of the reaction, the flask was immersed in an ice bath, and then 10 mL of methanol and 20 mL of distilled water were added sequentially. Then 10% hydrochloric acid is added for acidification, nucleic acid is added for removal of the reaction residue followed by water and ethanol, followed by washing using a 0.2 μm PTFE (Polyterafluoroethylene) membrane filter and vacuum oven Dry at (80 ° C.) for 12 hours.

It may also further comprise the step of sonicating in an aqueous phase and an organic phase for the stable dispersion of carbon nanotubes. In the present invention, the treatment was performed using ultrasonic waves generated at 28 kHz and 600 W.

Hereinafter, the present invention will be described in more detail with reference to Examples, but embodiments according to the present invention can be modified in many different forms, and the scope of the present invention is construed as being limited to the embodiments described below. Can not be done.

Example

Example 1 (Production of Spherical Polycarbonate Particles)

1. Preparation of Aqueous and Organic Phases and Preparation of Emulsions Using Homogenizers

In order to produce polycarbonate particles, a microemulsion method is used through phase separation of an aqueous phase and an organic phase through mixing using a homogenizer.

First, 4 wt% of polyvinylpyrrolidone is dissolved as a stabilizer in 10 mL of distilled water to prepare an aqueous phase. Next, 4 wt% of polycarbonate is dissolved in 10 mL of methylene chloride as a solvent while stirring at room temperature to prepare an organic phase. The prepared aqueous phase and organic phase were prepared in a volume ratio of 9: 1, and mixed at 20,000 Rpm using a homogenizer to prepare an emulsion. The prepared emulsion droplets form micro-sized droplets by phase separation, which is stabilized by stabilizers dissolved in aqueous phase.

2. Washing and Polycarbonate Particle Manufacturing

Since the prepared microemulsion contains methylene chloride as a solvent in the droplets, a washing process for removing the solvent is required to prepare the solid polycarbonate particles. To remove methylene chloride, the mixture is washed sufficiently with strong stirring with methylene chloride and insoluble polycarbonate using methanol. In addition, in order to completely remove the polyvinylpyrrolidone which is a stabilizer contained in the aqueous phase, it is washed once more with distilled water. The obtained polycarbonate particles are dried at room temperature for 24 hours for characterization and then dried for 24 hours under vacuum.

A schematic diagram of a method for producing spherical polycarbonate particles according to the present invention is shown in FIG. 1.

Example 2 (Preparation of spherical polycarbonate / carbon nanotube composite particles in which carbon nanotubes were introduced to the particle surface)

As shown in FIG. 2, the acid-treated carbon nanotubes were dispersed on an aqueous solution in which polyvinylpyrrolidone was dissolved in order to introduce carbon nanotubes to the surface of the polycarbonate particles. Carbon nanotubes were treated at 60 ^° C. for 12 hours in a 3: 1 mixed solution of nitric acid and sulfuric acid to remove impurities such as metal catalysts and introduce carboxyl groups. 0.03 wt% of acid treated carbon nanotubes in 10 mL of distilled water and 4 wt% of polyvinylpyrrolidone as a stabilizer for dispersing them were added, and a stable aqueous solution of carbon nanotube dispersion was obtained through sonication for 2 hours. Thereafter, polycarbonate / carbon nanotube composite particles in which carbon nanotubes were introduced on the surface of polycarbonate particles were prepared in the same manner as above using a homogenizer.

Example 3 (Preparation of spherical polycarbonate / carbon nanotube composite particles in which carbon nanotubes were introduced into particles)

In order to introduce carbon nanotubes into the polycarbonate particles as illustrated in FIG. 3, carbon nanotubes into which an alkyl group was introduced were dispersed in an organic phase. The method was carried out in the same manner as reported in the 2004 Nano Letter by F. Liang et. Al. Add 231 mg of lithium metal fragment with 60 mL of ammonia water to 20 mg of carbon nanotube, add 6.4 mmol of alkyl iodide and evaporate slowly for 12 hours while stirring. After the reaction, the solution is immersed in an ice bath, and then 10 mL of methanol and 20 mL of distilled water are added in order. Then 10% hydrochloric acid is added for acidification, nucleic acid, water, and ethanol are added in order to remove the reaction residue, followed by washing using a 0.2 μm PTFE (Polyterafluoroethylene) membrane filter, followed by a vacuum oven (80 ° C.). ) For 12 hours. The carbon nanotubes into which the alkyl group was introduced were stably dispersed in the organic phase in which polycarbonate was dissolved through ultrasonic treatment for 2 hours. The organic phase containing carbon nanotubes is obtained by using a homogenizer together with an aqueous phase in which polyvinylpyrrolidone is dissolved to obtain polycarbonate / carbon nanotube composite particles in which carbon nanotubes are introduced into polycarbonate particles. Can be.

Example 4 Characterization of Polycarbonate Particles and Polycarbonate / Carbon Nanotube Composite Particles

The surface properties of the polycarbonate particles and the polycarbonate / carbon nanotube composite particles were observed using a field emission scanning electron microscope (S-4300, Hitachi, Japan). Scanning electron micrographs were taken after the sample was fixed on an aluminum SEM disc and coated with platinum. Measurements were carried out at an acceleration voltage of 15 kV and an operating distance of 6 mm. High-resolution transmission electron microscopy was performed using a Philips CM 200 instrument and measured under an accelerating voltage of 120 kV. In order to observe the cross-section of the polycarbonate / carbon nanotube composite particles, the sample was epoxy-molded and manufactured in the form of very thin flakes using an ultra-thin slicer, and the small flakes formed at this time were 300 mesh coated with carbon. Placed on a copper grid of (Cu grid) and observed. The electrical conductivity of the polycarbonate / carbon nanotube composite particles was measured by a four-probe method. The purity of the acid-treated carbon nanotubes and the content of carbon nanotubes introduced into the surface and inside of the particles after the particle manufacturing process were measured using a thermogravimetric analyzer. Thermogravimetric analysis curves were measured by raising the temperature to 600 ^o C at 20 ^o C / min rate under nitrogen atmosphere.

Surface Characteristics of Spherical Polycarbonate Particles and Polycarbonate / Carbon Nanotube Composites and Location of Introduced Carbon Nanotubes

In the polycarbonate / carbon nanotube composite particles prepared in Examples 2 and 3, carbon nanotubes dispersed in an aqueous phase and an organic group were selectively introduced into the surface and inside of the polycarbonate / carbon nanotube composite particles.

4 is a scanning electron micrograph of the spherical polycarbonate particles of Example 1. Polycarbonate particles are spherical, have a uniform size of 0.5-3 μm and have a smooth surface.

FIG. 5 is a scanning electron micrograph of polycarbonate / carbon nanotube composite particles in which carbon nanotubes are introduced on a particle surface of Example 2, which is spherical like pure polycarbonate particles, and has a uniform size of 0.5 to 3 μm. . The bright part of the picture is due to the carbon nanotubes showing high conductivity, and the carbon nanotubes were uniformly distributed on the surface of the polycarbonate particles. In addition, it was confirmed that the carbon nanotubes located on the surface of the spherical polycarbonate particles form a network structure, and the improvement of the electrical conductivity of the prepared composite can be expected.

FIG. 6 is a scanning electron micrograph of a polycarbonate / carbon nanotube composite particle in which carbon nanotubes are introduced into particles of Example 3, wherein the particles have a spherical shape, and have a uniform size of 0.5 to 3 μm. However, since the carbon nanotubes are located inside the particles, it can be seen that the amount of carbon nanotubes appearing on the surface is relatively small compared to the case where they are dispersed in an aqueous solution. You can see it buried in the carbonate particles.

In order to confirm the carbon nanotubes introduced into the inside and the surface of the polycarbonate / carbon nanotube composite particles as presented in the present invention, the cross section of the composite particles was observed using a transmission electron microscope. The transmission electron micrograph shown in FIG. 7 is a cross-sectional view of a polycarbonate / carbon nanotube composite particle in which carbon nanotubes are introduced on a particle surface using a carbon nanotube dispersion aqueous solution, and the shape of carbon nanotubes adsorbed on a spherical particle surface. can confirm.

FIG. 8 is a polycarbonate / carbon nanotube composite particle in which carbon nanotubes are introduced into particles through dispersion of carbon nanotubes in an organic phase, and carbon nanotubes having a black tube (fibrous) material are located inside spherical particles. You can check.

Electrical Properties of Polycarbonate / Carbon Nanotube Composites

After the particle manufacturing process, the content of carbon nanotubes finally introduced into the surface and inside of the particles was measured using a thermogravimetric analyzer. The contents of the carbon nanotubes introduced into the surface and the inside of the polycarbonate / carbon nanotube composite particles were 7.0 wt% and 1.0 wt%, respectively.

As a plurality of carbon nanotubes are located on the surface of the particles, the electricity flows easily and exhibits a high electrical conductivity of 5.1 х 10 ^-2 S / cm.

On the other hand, when the carbon nanotubes are located inside the polycarbonate particles, the electrical flow is blocked by the polycarbonate, and thus exhibits a relatively low electrical conductivity of 7.19 х 10 ^-13 S / cm.

The embodiments presented above are exemplary and one of ordinary skill in the art may make various modifications and modifications to the embodiments presented without departing from the spirit of the present invention. Such modifications and variations are not intended to limit the scope of the invention.

The present invention provides a method for producing spherical polycarbonate particles and polycarbonate / carbon nanotube composite particles through a mixing process of a biphasic solution using a homogenizer, thereby making it difficult to form a polycarbonate that has been difficult to be spherical in the past. Spherical particles can be produced by a simple and efficient method. In addition, by dispersing the carbon nanotubes in the aqueous phase and the organic phase, the carbon nanotubes can be selectively introduced into the surface and the inside of the spherical polycarbonate particles. The method for producing the polycarbonate / carbon nanotube composite particles may be widely applied in the field of application of polycarbonate requiring different physical properties depending on the use. For example, carbon nanotubes can be selected on the surface for use in applications requiring good electrical conductivity, and carbon nanotubes can be introduced inside the particles for use in applications requiring physical properties. Can be selected. In addition, in order to take all of the properties of both of these may be prepared by combining the two production methods of the polycarbonate / carbon nanotube composite particles described above. In addition, by using a method of dispersing carbon nanotubes in an aqueous phase or an organic phase, a wide range of carbon nanotubes may be introduced.

1 is a schematic diagram showing a manufacturing process of spherical polycarbonate particles according to the present invention.

Figure 2 is a schematic diagram showing a process of introducing carbon nanotubes on the surface of the spherical polycarbonate particles according to the present invention.

Figure 3 is a schematic diagram showing a process of introducing carbon nanotubes into the spherical polycarbonate particles according to the present invention.

4 is a scanning electron micrograph of the spherical polycarbonate particles according to the present invention.

5 is a scanning electron micrograph of the spherical polycarbonate / carbon nanotube particles in which carbon nanotubes are introduced to the particle surface according to the present invention.

FIG. 6 is a scanning electron micrograph of spherical polycarbonate / carbon nanotube particles having carbon nanotubes introduced therein according to the present invention.

7 is a transmission electron micrograph showing a cross section of a spherical polycarbonate / carbon nanotube particles in which carbon nanotubes are introduced to the particle surface according to the present invention.

8 is a transmission electron micrograph showing a cross section of a spherical polycarbonate / carbon nanotube particles in which carbon nanotubes are introduced into the particles according to the present invention.

Claims (6)

In the manufacturing method of the spherical polycarbonate / carbon nanotube composite particles, Dispersing carbon nanotubes in an aqueous solution containing a stabilizer; And Preparing spherical polycarbonate / carbon nanotube composite particles by phase separation from an emulsion formed by homogeneously mixing the aqueous phase in which the carbon nanotubes are dispersed and the organic phase in which polycarbonate is dissolved. The spherical polycarbonate / carbon nanotube composite particles is a method for producing a spherical polycarbonate / carbon nanotube composite particles, characterized in that the carbon nanotubes are located on the surface of the polycarbonate. The method of claim 1, The carbon nanotubes are acid-treated with nitric acid or sulfuric acid to disperse in the aqueous phase, characterized in that the production of spherical polycarbonate / carbon nanotube composite particles. In the manufacturing method of the spherical polycarbonate / carbon nanotube composite particles, Dispersing carbon nanotubes in an organic phase in which polycarbonate is dissolved; And Preparing a spherical polycarbonate / carbon nanotube composite particle by phase separation from an emulsion formed by homogeneously mixing an organic phase in which the carbon nanotubes are dispersed and an aqueous solution phase including a stabilizer. The spherical polycarbonate / carbon nanotube composite particles is a method for producing a spherical polycarbonate / carbon nanotube composite particles, characterized in that the carbon nanotubes are located inside the polycarbonate. The method of claim 3, wherein The carbon nanotubes are spherical polycarbonate / carbon nanotube composite particles, characterized in that dispersed in the organic phase by introducing an alkyl group using a metal catalyst and an alkyl halide. delete Spherical polycarbonate, characterized in that the carbon nanotubes are located inside or on the surface of the spherical polycarbonate particles, the particle size is 0.5 ~ 3㎛, the electrical conductivity is 7.19x10 ^-13 ~ 5.1x10 ^-2 S / cm / Carbon nanotube composite particles.

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