KR20130020430A - Conductive polymer complex and forming method thereof - Google Patents

Abstract

PURPOSE: A conductive polymer complex and its molding method implements the high conductivity with a low density content of the carbon nanotube, thereby reduce cost and a phenomenon of degrading workability. CONSTITUTION: A conductive polymer complex and its molding method comprises a step of manufacturing liquidized or melted polymer complex by mixing the polymer complex and the carbon nanotube, and a step of extrusion molding the manufactured polymer complex. By forming the electric field to cross the direction of mobility of the polymer complex in the extrusion molding step, the orientation of the carbon nanotube is reduced. The polymer complex is selected in the group consisting of the thermoplastic polymer and the thermoset polymer. In the total 100 weight% of the polymer complex, the carbon nanotube is included about 0.3~5 weight%. The viscosity of the polymer complex is 500~800,000 Pas. In case of the electric field is the direct current, the electric field of 80 through 120V is given for 1~10 minutes. In case of the electric field is the alternating current, the electric field of 80 through 120V, and 50 through 60HZ is given for 1~10 minutes. [Reference numerals] (AA,CC) Extruder; (BB) T die; (DD) Electrode; (EE) First step; (FF) Second step-side; (GG) Second step-front

Description

Conductive polymer complex and forming method

The present invention relates to a method for forming a conductive polymer composite related to a post-treatment process during extrusion processing to improve electrical properties of the conductive polymer composite, and a conductive polymer composite obtained by the molding method.

Since carbon nanotubes (CNTs) were first discovered by Iijima using the electric discharge method, there has been a great deal of research being carried out with increasing interest in these new carbon materials at home and abroad. The first carbon nanotubes discovered by Iijima are 200 times stronger than steel, with excellent elastic modulus, heat resistance at temperatures up to 2800 ° C in vacuum, thermal conductivity nearly twice that of diamond, and 1000 times higher than copper. Because of its high current carrying capacity, its application potential is highly appreciated in all engineering fields, including materials.

Carbon nanotubes are usually carbon materials having a high aspect ratio, having a diameter of 1 to 100 nanometers (nm) and a length of several nanometers (nm) to several tens of micrometers (μm). Carbon nanotubes have a honeycomb-shaped planar carbon structure in which one carbon atom is bonded to three other carbon atoms to form a tube. There are many types of carbon nanotubes, which can be divided into multi-walled nanotubes (MWNTs) and single-walled nanotubes according to the number of walls constituting the nanotubes. Among these, nanotubes consisting of two or more walls are called multi-walled nanotubes, and nanotubes consisting of only one wall are called single-walled nanotubes.

Due to the high electrical conductivity, thermal stability, tensile strength, and recoverability of the carbon nanotubes, the carbon nanotubes are used as additives in various composite materials. When carbon nanotubes are used as additives in the composite material, how effectively the bundles of carbon nanotubes are dispersed in a solvent is a very important factor. In the case of the polymer / carbon nanotube composite material, how effectively the carbon nanotubes are dispersed in the polymer matrix is also very important. However, due to the long length of the carbon nanotubes and the strong attraction between the carbon nanotubes, there is a problem that the carbon nanotubes have a very low dispersion degree in the solvent.

A chemical method of modifying the surface of carbon nanotubes by dispersing polymer / carbon nanotube composites to improve conductivity and a physical method of releasing agglomeration of carbon nanotubes through ball-mill, ultrasonic waves or plasma. There is, but this improves the dispersibility of the carbon nanotubes, but in order to maintain the electrical conductivity, an excess content of 1% by weight or more is added. By adding an excessive amount of carbon nanotubes, the connection probability can be increased to maintain electrical connection between the carbon nanotubes to realize conductivity until the molding step.However, the higher the carbon nanotube content, the higher the cost, the lower the mechanical properties, This causes problems such as an increase in the viscoelasticity of the composite involved in processing.

On the other hand, there is a tubular / spherical mixed dispersion method having a different aspect ratio using a carbon nanotube content which is relatively difficult to disperse and mixing carbon black or metal powder. This effectively reduced the content of carbon nanotubes, but because of the high content of the spherical powder additive, the viscoelasticity of the composite is increased, the workability is lowered, mechanical properties such as elongation is lowered.

Most of the molding step of the polymer composite which requires the electrical properties of the electroconductivity / anti-charge is a pressure / injection process is very high shear strain in a short time. In this process, the electrical connection structure formed between the tubes in the carbon nanotube dispersion step is broken by the high shear deformation imparted in the process, and the carbon nanotubes are oriented in the flow direction to lose electrical properties. In addition, there is a problem that the surface electrical properties of the final molded product is lowered or disappeared because the polymer melt having high mobility (mobility) occupies a surface portion with high shear flow in the carbon nanotube and the polymer melt. In order to supplement the problems in the process and increase the probability of connection, a method of adding more carbon nanotubes than necessary content is used, resulting in high manufacturing cost and poor workability.

Accordingly, the present invention is to provide a method for forming a polymer / carbon nanotube composite having a high antistatic and electrical conductivity with a content of less carbon nanotubes than the conventional method in the processing of polymers with high viscosity polymer melt or solution do.

The present invention comprises the steps of preparing a liquefied or molten polymer composite by mixing the polymer and carbon nanotubes; And extruding the prepared polymer composite, and forming an electric field so as to be orthogonal to the direction of the flow of the polymer composite during extrusion, thereby reducing the orientation of the carbon nanotubes. Provide a method.

The polymer may be any one or two or more selected from the group consisting of a thermoplastic polymer and a thermosetting polymer.

The carbon nanotubes in the total 100% by weight of the polymer composite is preferably contained in 0.3 to 5% by weight.

The viscosity of the polymer composite is preferably 500 ~ 800,000 Pas.

In the case of direct current, the electric field gives an electric field of 80 to 120V for 1 to 10 minutes, and in the case of an alternating current, it is preferable to give an electric field of 80 to 120V and 50 to 60 Hz for 1 to 10 minutes.

More specifically, the present invention 1) a first step of liquefying or melting the polymer; 2) preparing a polymer composite by mixing carbon nanotubes with the liquefied or molten polymer; 3) passing the polymer composite through the outlet of the extruder; And 4) a fourth step of reducing the orientation of the carbon nanotubes by forming an electric field orthogonal to the direction of the polymer composite flow passed through the discharge port.

In addition, the molding method 1) a first step of liquefying or melting the polymer; 2) a second step comprising 0.3 to 5% by weight of carbon nanotubes in a total of 100% by weight of the polymer composite prepared by mixing carbon nanotubes with the liquefied or molten polymer; 3) a third step of passing the polymer composite to the outlet of the extruder having a viscosity of 500 ~ 800,000 Pas; And 4) reducing the orientation of the carbon nanotubes by forming an electric field of 80 to 120V DC for 1 to 10 minutes orthogonal to the direction of the polymer composite flow passed through the outlet.

In addition, the present invention provides a conductive polymer composite, which is manufactured by the molding method, characterized in that the orientation of the carbon nanotubes is reduced and the electrical connection structure can be formed to maintain electrical conductivity.

The present invention forms an electric field in the electrical connection structure disappeared by the orientation of the carbon nanotubes dispersed in the forming step to reduce the orientation and restore the electrical connection structure, and implements high conductivity with a low content of carbon nanotubes. As a result, cost reduction and workability deterioration can be reduced. This molding method is difficult to apply to injection molding with a short process time because it is to control the orientation in the processing of polymers with high viscosity polymer melt or solution, it can be applied more effectively to the extrusion process.

Figure 1 shows that the electric field is irradiated when the polymer composite of the present invention at the outlet in the first step through the outlet (T-die) of the extruder and the second step of the sheet forming step of the polymer composite.
Figure 2 shows the arrangement of carbon nanotubes changed by irradiating an electric field in addition to the arrangement of conventional carbon nanotubes when passing through the outlet (T-die) of the sheet forming process.
Figure 3 shows that the orientation of the carbon nanotubes is excluded by irradiating the electric field in the sheet forming machine through the outlet (T-die).
Figure 4 shows an external picture of the Haake twin screw internal mixer.
5 shows the electric field irradiation and conductivity measurement equipment.
Figure 6 shows the change in electrical conductivity according to the electric field change of the composite prepared in Example 1.
Figure 7 shows the change in electrical conductivity with the electric field irradiation time of the composite prepared in Example 1.
Figure 8 shows the change in electrical conductivity according to the carbon nanotube content of the composite prepared in Example 2.

The present invention comprises the steps of preparing a liquefied or molten polymer composite by mixing the polymer and carbon nanotubes; And extruding the prepared polymer composite, and forming an electric field so as to be orthogonal to the direction of the flow of the polymer composite during extrusion, thereby reducing the orientation of the carbon nanotubes. Provide a method.

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

Conventionally, when dispersing a post-treatment step to improve conductivity in a polymer-carbon nanotube composite, a large amount of 1 to 2% by weight or more is added to impart electrical conductivity to a polymer using carbon nanotubes, but the molding process of the applied product The high shear strain imparted to the carbon nanotubes is oriented in one direction, leading to breakage of the electrical connection structure, thereby causing the electrical conductivity to disappear. In order to compensate for this, an excessive amount of carbon nanotube is added to reduce the gap between the carbon nanotubes, but this lowers mechanical properties such as stretchability and elastic modulus of the polymer composite. Therefore, the inventors of the present invention, while trying to manufacture a polymer-carbon nanotube composite having a high antistatic and electrical conductivity with a small content of carbon nanotubes, according to the molding method of the present invention, the carbon added to implement the electrical conductivity Even though reducing the content of the nanotube it was confirmed that it can improve the degradation of the resulting electrical properties and completed the present invention.

The present invention is an extrusion molding, forming a conductive field orthogonal to the direction of the flow of the polymer composite liquefied or molten polymer and carbon nanotubes to remove the orientation of the carbon nanotubes; Provide a method.

More specifically, the molding method of the conductive polymer composite

1) first step of liquefying or melting the polymer;

2) a second step of producing a polymer composite by mixing carbon nanotubes in the liquefied or molten polymer;

3) a third step of passing the mixed polymer composite through the outlet of the extruder; And

4) a fourth step of eliminating the orientation of the carbon nanotubes by forming an electric field orthogonal to the direction of the polymer composite flow through the outlet.

Polymer Liquefaction  Or the first step of melting

The polymer may be selected from the group consisting of a thermoplastic polymer and a thermosetting polymer.

In the present invention, the thermoplastic polymer is not particularly limited, but may include all of polyethylene, polypropylene, vinyl, acrylic, methacryl, polyolefin, nylon, and the like, preferably polyethylene, polypropylene, Or nylon based.

In the present invention, the thermosetting polymer is not particularly limited, but may include an epoxy system.

The polymer is preferably in a fluid state, for example, liquefied or melted, for easy flow.

When the polymer is melted, it may be provided by a method of applying high heat, and as an example of the present invention, the thermoplastic polymer or the thermosetting polymer may be melted at 160 to 220 ° C. for 30 seconds to 5 minutes.

The polymer may be either a thermoplastic polymer or a thermosetting polymer, but may optionally use a mixture thereof.

The liquefied or molten polymer mixture at this time is not particularly limited, but phase separation does not occur in the liquefied state or molten state. More specifically, the polymer solution prepared by dissolving the mixed polymer in a soluble solvent, respectively or in a mixed state may not be preferably phase separated from each other in the mixed solution, if the phase separation in the liquid state in which the polymer mixture is dissolved If this occurs, the problem is that each of the single fiber rather than the mixed polymer may occur, so be careful in their selection.

Liquefaction  Or a second step of producing a polymer composite by mixing carbon nanotubes with the molten polymer

In the present invention, the carbon nanotubes are hollow tube structures in which an elongated cylinder-shaped graphite (graphite) surface is rounded, and the carbon nanotubes usable in the present invention are all types of carbon nanotubes. However, single-walled carbon nanotube (SWCNT), double-walled carbon nanotube (DWCNT), multi-walled carbon nanotube (MWCNT), rope-type carbon nanotube It may include a tube (roped carbon nonotube) or a mixture of two or more types of carbon nanotubes of each type, preferably single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes ( multi-walled carbon nanotube, MWCNT).

Carbon nanotubes exhibit excellent mechanical strength and elasticity due to the rigid structure of the graphite surface, are chemically stable, and exhibit various electrical properties from conductors to semiconductors depending on the angle and structure of the graphite surface being curled. In addition, the nano-size and high aspect ratio (surface area) is very large surface area has the advantage as an excellent advanced material.

The length of the carbon nanotubes is not particularly limited, but may be 0.01 to 30 μm, and preferably 0.1 to 10 μm.

When the polymer composite (the composite of the polymer and carbon nanotubes in the present specification is called a polymer composite) is 100 wt% in total, the weight part of the carbon nanotubes in 100 wt% is not particularly limited, but preferably 0.3 to It is preferably included in 5% by weight.

When the amount of the carbon nanotubes is less than 0.3% by weight, there is a fear that the path between the carbon nanotubes can conduct electricity, and when the amount of the carbon nanotubes is more than 5% by weight, the electrical conductivity is insignificant. On the other hand, problems can arise such as an increase in cost, a decrease in mechanical properties, and an increase in the viscoelasticity of the composites involved in processing.

The content of the carbon nanotubes of the present invention brought an excellent improvement of the electrical properties by the molding method of the present invention, even at a concentration below that of forming a net structure generally known as a low concentration that does not conventionally exhibit sufficient electrical properties. The addition of low content hardly gives a difference to the rheological properties of the polymer composites, and thus does not cause a decrease in processability and mechanical properties.

The method of mixing the carbon nanotubes with the polymer is not particularly limited, but as an example of the present invention, a twin-screw internal mixer or a twin screw extruder (L / D) for melt-mixing the polymer with the carbon nanotubes = 16) can be mixed for 5 to 10 minutes at 30 to 80 rpm.

Third step through which the mixed polymer composite passes through the outlet of the extruder

When the polymer composite mixed in the second step passes through the molding machine, it is preferable to apply an electric field to the polymer composite in the molten or liquid state rather than the polymer composite in the solid state in order to improve the electrical conductivity.

In the molten or liquid polymer composite as shown in the present invention, the carbon nanotubes can be actively dispersed and effectively dispersed, thereby improving the electrical conductivity, while in the polymer composite in which the solid state or viscosity is not large, the carbon nano Due to the slow motion of the tube, dispersion does not occur sufficiently, and carbon nanotubes are agglomerated to form a network in the polymer composite. Therefore, the polymer composite can pass through the outlet without undergoing a cooling process.

In the present invention, the polymer composite melted at 160 to 220 ° C. for 30 seconds to 5 minutes can be passed through the outlet without cooling. The polymer composite exhibiting good electrical conductivity at this time may have a viscosity of 500 to 800,000 Pas, preferably For sure it can be 5000 ~ 50,000 Pas.

If the viscosity of the polymer composite is lower than the viscosity, there is a problem that smooth control of extrusion molding is difficult. If the viscosity is higher than the viscosity, the mobility of carbon nanotubes is slowed and the dispersion is poor, resulting in low electrical conductivity. Can be.

In one example of the present invention, at 180 ° C., the thickness may be in a state of being molded into a circular platelet having a diameter of 1 mm and a diameter of 25 mm, wherein the viscosity may be 100,000 Pas.

The molding process in which the molding method of the conductive polymer composite of the present invention is used is not particularly limited, and extrusion molding including sheet casting, thermoforming and blow molding may be performed. Although all may be included, preferably sheet molding and extrusion molding may be effective.

The present invention may not be suitable for injection molding, which is because the injection molding is fired for a short time and the molding time is only a few seconds, so that the orientation of the carbon nanotubes is insufficiently unbalanced so that the orientation may be formed. In the extrusion molding of the present invention, the orientation of the carbon nanotubes may be unbalanced because the molding time is sufficiently relaxed.

If the orientation of the carbon nanotubes is removed by extrusion molding as in the present invention, the carbon nanotubes are in contact with each other, so that the surface resistance value may be reduced by mutual contact of the carbon nanotubes, and thus the electrical conductivity of the polymer composite may be increased. .

Of the carbon nanotubes by forming an electric field perpendicular to the direction of the polymer composite flow through the outlet. Orientation  4th step to get rid of

Surface resistance (Ohn / sq) is calculated as the inverse of the electrical conductivity (Electrical Conductivity (siemens / m), the lower the surface resistance value may mean that the higher the electrical conductivity.

Therefore, while extruding the molten or liquefied carbon nanotube and polymer composite at a high temperature of the present invention, by forming an electric field orthogonal to the direction of the flow of the polymer composite, when the orientation of the carbon nanotube is removed, the disorder becomes stronger, and the surface resistance This lowers the electrical conductivity is improved to obtain a conductive polymer composite with excellent efficiency.

The orientation forms an electric field in a direction orthogonal to the flow direction of the polymer composite, and adjusts the direction and intensity of the external electric field according to the viscosity of the polymer composite and the content of the carbon nanotubes, thereby changing the arrangement of the carbon nanotubes in one direction. By preventing the removal of the orientation of the carbon nanotubes can maintain the conductivity of the surface.

In the present invention, an electric field of 80 to 120V of direct current can be applied for 1 to 10 minutes, and preferably, 1 to 2 minutes at 100V.

In the present invention, the electric field of 80 to 120V, 50 to 60Hz of alternating current can be applied for 1 to 10 minutes, and preferably, 1 to 2 minutes at 100V and 60 Hz.

Among the alternating current and direct current electric fields, a direct current electric field may be more preferable. As shown in FIG. 6, both direct current and alternating current showed improved electrical conductivity of the composite, and direct current showed higher electrical conductivity than alternating current. .

The lower the viscosity of the polymer composite in the viscosity of the present invention can improve the mobility (mobility) of carbon nanotubes, the lower the viscosity at the deformation rate of the molding process may require a shorter electric field irradiation time.

In addition, the higher the content of the carbon nanoparticles constituting the polymer composite, the shorter the irradiation time applied to the electric field, and the lower the content, the longer the irradiation time of the oriented carbon nanoparticles should be induced.

Therefore, the electric field irradiation time of the present invention may be a time sufficient to remove the orientation and exhibit high electrical conductivity when the polymer composite according to the present invention as shown in FIGS. 7 and 8.

That is, as shown in Figure 7, when irradiated with an electric field for 1 minute has an effect of increasing the electrical conductivity by more than 20% than the polymer composite without irradiating the electric field, the effect of increasing the conductivity by 2000% when irradiated with electric field for 3 minutes There is. In addition, as shown in Figure 8, in the case of a polymer composite containing 0.3% by weight of carbon nanotubes irradiated with an electric field for 10 minutes or more, the electrical conductivity of the sample containing 1.0% by weight of carbon nanotubes without applying an electric field The electrical conductivity of the composite (2x10 ^-4 S / m) was confirmed to show a higher value.

In a preferred embodiment of the present invention, the molding method of the conductive polymer composite

1) the first step of liquefying or melting the polymer,

2) when the carbon nanotubes are mixed with the liquefied or molten polymer to produce a polymer composite, a second step of including carbon nanotubes in a content of 0.3 wt% in 100 wt% of the polymer composite;

3) a third step in which the mixed polymer composite has a viscosity of 1000 Pas and passes through the outlet of the extruder, and

4) a fourth step of eliminating the orientation of the carbon nanotubes by forming an electric field of 100V direct current for 2 minutes orthogonal to the direction of the polymer composite flow through the outlet.

In the molding method according to the embodiment of the present invention, the polymer composite of the present invention is completely disorganized in orientation so that the electrical connection structure is restored to implement high conductivity with a low content of carbon nanotubes, and the results are confirmed in FIGS. 7 and 8. Can be.

The present invention provides a conductive polymer composite in which the orientation of the carbon nanotubes prepared by the molding method is lost.

The conductive polymer composite, because of the high shear strain applied to the conventional molding process, the electrical conductivity disappears and the surface resistance is increased, the carbon nanotube of more than necessary content is added to extend the stretch (extendibility), elastic modulus, etc. It is to solve the problem of lowering the mechanical properties.

When the polymer composite is 100% by weight in total, the carbon nanotubes in total 100% by weight may be included in 0.3 ~ 5.0% by weight.

The viscosity of the polymer composite may be 500 ~ 800,000 Pas.

The electric field may give an electric field of 80 to 120V for 1 to 10 minutes in the case of direct current.

The electric field may give an electric field of 80 to 120V, 50 to 60Hz for 1 to 10 minutes in the case of alternating current.

The polymer composite of the present invention is disordered in the orientation of the carbon nanotubes to be in contact with each other even when shear deformation, and the electrical connection structure between the carbon nanotubes is not broken, the electrical conductivity is high and the surface resistance can be kept low, thus unnecessary It is excellent in mechanical properties such as elongation and elastic modulus of polymer composite without addition of high capacity carbon nanotubes, and electrical properties such as antistatic ability, electric conductivity, and electromagnetic shielding effect of polymer composite because carbon nanotubes are uniformly dispersed without aggregation. Rheological properties such as viscosity and storage modulus are all excellent.

Hereinafter, the present invention will be described in more detail with reference to Examples, Comparative Examples and Experimental Examples. However, the following Examples, Comparative Examples and Experimental Examples illustrate the present invention, and the content of the present invention is not limited to the following Examples, Comparative Examples and Experimental Examples.

< Example >

Example  1: Preparation of Polypropylene and Carbon Nanotube Composites by Extrusion

50 g of polypropylene (PP) manufactured by polymirae was added to a biaxial internal mixer, and the polypropylene was melted while rotating the screw at 15 rpm for 1 minute at 180 ° C. 0.15 g of carbon nanotubes were added to the molten polypropylene and mixed by rotating the screw at 50 rpm for 7 minutes. A polypropylene resin composition containing 0.3 wt% of final carbon nanotubes was obtained. The composite was extruded into a circular platelet having a thickness of 1 mm and a diameter of 25 mm at 180 ° C., followed by an electric field. At this time, the electric field was conducted at 100V DC, 100V, 60Hz AC respectively.

Example  2: Preparation of Polyethylene and Carbon Nanotube Composites by Extrusion

50g of High Density Polyethylene (HDPE 2200J) manufactured by Honam Petrochemical Co., Ltd. was added to a twin screw internal mixer, and the HDPE resin was melted by rotating the screw at 15 rpm for 1 minute at 180 ° C. 0.15 g of carbon nanotubes were added to the molten HDPE resin, followed by mixing by rotating the screw at 50 rpm for 7 minutes. An HDPE resin composition containing 0.3 wt% of final carbon nanotubes was obtained. The composite was extruded into a circular platelet having a thickness of 1 mm and a diameter of 25 mm at 180 ° C., followed by an electric field. At this time, the electric field was conducted at 100V DC, 100V, 60Hz AC.

Comparative example  1: Preparation of Polypropylene and Carbon Nanotube Composites by Injection Molding

Polypropylene and carbon nanotube composites were prepared in the same manner as in Example 1, but were prepared by injection molding rather than extrusion.

Comparative example  2: Preparation of Polyethylene and Carbon Nanotube Composites by Injection Molding

Polyethylene and carbon nanotube composites were prepared in the same manner as in Example 2, but were prepared by injection molding rather than extrusion.

Experimental Example  1: Examine the change in conductivity

Experimental Example  1-1: Changes in Electrical Conductivity of Polypropylene and Carbon Nanotube Composites

The polypropylene and carbon nanotube composites prepared according to Example 1 were subjected to an electric field under a 100 V direct current and 100 V, 60 Hz alternating current, or to an electric field irradiation time of 0 minutes, 1 minute, 3 minutes, 5 minutes, 10 minutes, 20 minutes, 30 minutes. The change in electrical conductivity was investigated in different minutes.

As a result, as shown in Figure 6, both the direct current and the alternating current showed an improvement in the electrical conductivity of the composite, it was confirmed that the direct current shows a higher electrical conductivity than the alternating current.

In addition, as shown in FIG. 7, when the electric field is irradiated for 1 minute, the electrical conductivity is increased by 20% or more than the polymer composite not irradiated with the electric field, and when the electric field is irradiated for 3 minutes, the conductivity is increased by 2000%. It was confirmed that there is an effect.

Experimental Example  1-2: Changes in Electrical Conductivity of Polyethylene and Carbon Nanotube Composites

The change in electrical conductivity of the polyethylene and carbon nanotube composites prepared in Example 2 was investigated under an electric field under 100 V direct current or by varying the electric field irradiation time to 0 minutes and 10 minutes.

As a result, as shown in FIG. 8, in the case of the polymer composite containing 0.3 wt% carbon nanotube irradiated with an electric field for 10 minutes or more, the electrical conductivity of the sample contained 1.0 wt% carbon nanotube without applying an electric field. The electrical conductivity of the polymer composite (2x10 ^-4 S / m) was confirmed to show a higher value.

On the other hand, in the case of the composite molded by injection molding as in Comparative Example 1 and Comparative Example 2, since the molding is completed within a short time, that is, 30 seconds for the injection molding process, the flow in the same state as the molten state for a certain time longer than 30 seconds during molding It was not possible to achieve the technical effect according to the present invention in which electric field irradiation was required while maintaining this easy fluid state.

Claims (9)

Preparing a liquefied or molten polymer composite by mixing the polymer with carbon nanotubes; And
Comprising the step of extruding the prepared polymer composite,
Forming an electric field so as to be orthogonal to the direction of the flow of the polymer composite during extrusion molding, characterized in that to reduce the orientation of the carbon nanotubes, the molding method of the conductive polymer composite. The method of claim 1, wherein the polymer is selected from the group consisting of a thermoplastic polymer and a thermosetting polymer. The method of claim 1, wherein the carbon nanotubes are contained in an amount of 0.3 to 5% by weight in 100% by weight of the polymer composite. The method of claim 1, wherein the viscosity of the polymer composite is 500 to 800,000 Pas. The method of forming a conductive polymer composite according to claim 1, wherein the electric field imparts an electric field of 80 to 120V for 1 to 10 minutes in the case of direct current. The method of forming a conductive polymer composite according to claim 1, wherein the electric field imparts an electric field of 80 to 120 V and 50 to 60 Hz for 1 to 10 minutes in the case of alternating current. The method of claim 1,
1) first step of liquefying or melting the polymer;
2) preparing a polymer composite by mixing carbon nanotubes with the liquefied or molten polymer;
3) passing the polymer composite through the outlet of the extruder; And
4) a fourth step of reducing the orientation of the carbon nanotubes by forming an electric field orthogonal to the direction of the polymer composite flow passed through the outlet;
Forming method of a conductive polymer composite comprising a. 8. The method of claim 7,
1) first step of liquefying or melting the polymer;
2) a second step comprising 0.3 to 5% by weight of carbon nanotubes in a total of 100% by weight of the polymer composite prepared by mixing carbon nanotubes with the liquefied or molten polymer;
3) a third step of passing the polymer composite to the outlet of the extruder having a viscosity of 500 ~ 800,000 Pas; And
4) a fourth step of reducing the orientation of the carbon nanotubes by forming an electric field of 80 to 120V DC for 1 to 10 minutes orthogonal to the direction of the polymer composite flow passed through the outlet;
Containing, forming method of the conductive polymer composite. A conductive polymer composite obtained by the molding method of any one of claims 1 to 8, wherein the orientation of the carbon nanotubes is reduced and an electrical connection structure can be formed to maintain electrical conductivity.

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