KR102514631B1 - Manufacturing Method of Carbon Nanotube Masterbatch and Manufacturing Method of Electroconductive Polymer Composite by Using the Same - Google Patents

Abstract

The present invention is a method for producing a carbon nanotube masterbatch,
Based on the total weight of the carbon nanotube masterbatch, 45 to 65% by weight of carbon nanotubes and 55 to 35% by weight of wax are prepared after melting and mixing at 30 to 160 ° C.
The wax is selected from the group consisting of fatty alcohols, lipid acids, soaps, fatty acid amides, fatty acid esters, polyolefin waxes, paraffins, and combinations thereof Method for producing a carbon nanotube masterbatch and an electrically conductive polymer composite using the same Provides a manufacturing method of.

Description

Manufacturing Method of Carbon Nanotube Masterbatch and Manufacturing Method of Electroconductive Polymer Composite by Using the Same}

The present invention relates to a method for preparing a carbon nanotube masterbatch containing high-concentration carbon nanotubes and a method for preparing a polymer composite exhibiting excellent electrical conductivity using the same.

A carbon nanotube masterbatch is added to impart electrical conductivity to an electrical insulating plastic material or the like. While utilizing the individual characteristics of the carbon nanotube masterbatch and the electrical insulating plastic material, various techniques have been studied for uniform mixing.

For example, KR20110095295A provides a method for preparing a carbon nanotube masterbatch from a composition comprising a specific propylene olefin-copolymer wax and carbon nanotubes. CN104744788A provides a method for preparing a carbon nanotube masterbatch in which 20 to 80 wt% carbon nanotubes and 20 to 80 wt% ethylene-vinyl acetate polymer are prepared as carriers. CN107057176A contains 10~40wt% CNT, 1~5wt% coupling agent, 40~80wt% polymer carrier material, 20~30wt% compatibilizer and 10~20wt% lubricant, prepared by kneader-extruder, twin screw extruder or mill It provides a method and composition for preparing a carbon nanotube masterbatch. CN111171430A provides a composition and manufacturing method of a carbon nanotube masterbatch containing white oil, an emulsifier, an antioxidant, carbon nanotubes and powdered polyolefin.

These prior arts disclose a method of preparing a carbon nanotube masterbatch by mixing carbon nanotubes with various polymers, but most of them use a polymer-based carrier to form a copolymer. However, such a polymer-type carbon nanotube masterbatch may cause deterioration in mechanical properties of a final product due to a difference in polymer grade, and high energy consumption is uneconomical because high-temperature conditions are required in the manufacturing process.

Therefore, it is necessary to research a new type of carbon nanotube masterbatch that can increase energy efficiency in the production process without deteriorating the mechanical properties of the final product and a method for preparing a polymer composite exhibiting excellent electrical conductivity using the masterbatch. .

An object of the present invention is to provide a method for preparing a carbon nanotube masterbatch having excellent mechanical properties without using a polymer as a carrier.

Another object of the present invention is to prepare an electrically conductive polymer composite having high economic feasibility and high production efficiency using the prepared carbon nanotube masterbatch.

The present invention is a method for producing a carbon nanotube masterbatch,

Based on the total weight of the carbon nanotube masterbatch, 45 to 65% by weight of carbon nanotubes and 55 to 35% by weight of wax are prepared after melting and mixing at 30 to 160 ° C.

The wax provides a method for producing a carbon nanotube masterbatch selected from the group consisting of fatty alcohols, lipid acids, soaps, fatty acid amides, fatty acid esters, polyolefin waxes, paraffins, and combinations thereof.

As an example, the wax is selected from the group consisting of fatty acid amides, fatty acid esters, polyolefin waxes, and combinations thereof,

The fatty acid esters include glyceryl monostearate, glyceryl distearate, glyceryl tristearate, ethylene glycol esters of montanic acids, mon montanic acid glyceryl ester, trimethylolpropane monostearate, sorbitol tristearate, sorbitol distearate, sorbitol monostearate, penta erythritol tetrastearate, pentaerythritol tristearate, pentaerythritol distearate, pentaerythritol monostearate, and combinations thereof.

It is prepared by melting and mixing 50 to 60% by weight of carbon nanotubes and 40 to 50% by weight of wax at 60 to 80° C. based on the total weight of the carbon nanotube masterbatch, and the wax may be a fatty acid ester.

The carbon nanotubes may include single-walled carbon nanotubes, multi-walled carbon nanotubes, or a combination thereof.

The carbon nanotube masterbatch may be prepared in the form of pellets by using a single screw extruder, a twin screw extruder, or a combination thereof.

In addition, the present invention is a method for preparing an electrically conductive polymer composite,

Method for preparing an electrically conductive polymer composite prepared by melting and mixing 84 to 96% by weight of a polymer resin, 0.1 to 0.5% by weight of an antioxidant, and 3 to 17% by weight of the carbon nanotube masterbatch based on the total weight of the electrically conductive polymer composite provides

The polymer resin is polyester, polyolefin, polyvinyl chloride, polystyrene, rubber-modified polystyrene, polyimide, polyamide, polyetherimide, polycarbonate, polyetherketone, polyetheretherketone, polyaryleneether, polysulfone, polydiphenylsulfide, copolymers of acrylonitrile and butadiene, thermoplastic polyurethanes, polyacetals, and combinations thereof.

Melt mixing of the electrically conductive polymer composite may be performed at 160 to 240°C.

The present invention is also prepared by melting and mixing 84 to 96% by weight of polyolefin, 0.1 to 0.5% by weight of antioxidant, and 3 to 10% by weight of the carbon nanotube masterbatch with a polymer resin based on the total weight of the electrically conductive polymer composite. A method for preparing an electrically conductive polymer composite is provided.

Since the carbon nanotube masterbatch prepared in the present invention does not use a polymer as a carrier, mechanical property degradation due to a difference in polymer grade in the final product can be minimized. This carbon nanotube masterbatch can be produced at low temperatures, so energy consumption can be significantly reduced, and the production efficiency is excellent.

Ultimately, an electrically conductive polymer composite having excellent mechanical properties and exhibiting high gloss, improved surface smoothness and improved black surface color can be prepared using the carbon nanotube masterbatch prepared in the present invention.

1A is a photograph of carbon nanotube master batch pellets prepared in Examples 1-6 according to Experimental Example 1;
1B is a photograph of polymer composite pellets prepared in Examples 2-6 according to Experimental Example 1;
2a is a photograph of an electrically conductive polymer composite sheet prepared in Examples 2-6 according to Experimental Example 2; and
2B is a photograph of an electrically conductive polymer composite sheet prepared in Comparative Example 2-1 according to Experimental Example 2;

Manufacturing method of carbon nanotube masterbatch

The present invention is a method for producing a carbon nanotube masterbatch,

Based on the total weight of the carbon nanotube masterbatch, 45 to 65% by weight of carbon nanotubes and 55 to 35% by weight of wax are prepared after melting and mixing at 30 to 160 ° C.

The wax is selected from the group consisting of fatty alcohols, lipid acids, soaps, fatty acid amides, fatty acid esters, polyolefin waxes, paraffins, and combinations thereof, and provides a method for producing a carbon nanotube masterbatch.

The carbon nanotube masterbatch prepared in the present invention is a form in which carbon nanotubes are dispersed in wax, and the dispersibility of the carbon nanotubes is improved by the wax. In addition, this carbon nanotube masterbatch is a non-polymer system that does not use a high-molecular polymer as a carrier, and can minimize mechanical property degradation due to a difference in polymer grade in a final product. Here, not using a high-molecular polymer as a carrier means that a copolymer of a high-molecular polymer carrier other than a wax component is not included.

The wax may contain fatty alcohol. These fatty alcohols include myristyl alcohol, pentadecanol, cetyl alcohol, heptadecanol, stearyl alcohol, nonadecanol, arachidyl alcohol, henicosanol, behenyl alcohol, tricosanol, lignoceryl alcohol, pentacosanol, hexacosanol, heptacosanol, octacosanol, nonacosanol, tricontanol, brown coal base alcohol and their Can be selected from a combination of.

The wax may include a lipid acid. These lipid acids may be selected from lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, lignoceric acid, wax alkanoic acid, montanic acid, and combinations thereof.

The wax may include soap. These soaps are composed of calcium laurate, calcium myristate, calcium palmitate, calcium stearate, calcium arachidate, calcium oleate, calcium linoleate, calcium montanic acid, zinc laurate, zinc myristate, zinc palmitate, zinc stearate, zinc oleate, zinc linileate and combinations thereof. can be selected.

The wax may include fatty acid amides. These fatty acid amides are laurylamide, myristic amide, palmitic amide, stearylamide, behenamide, oleamide, erucamide, ethylene bis lauramide, ethylene bis palmitamide, ethylene bis stearamide, oleyl plamitamide, streayl erucamide, peanut acid amides, tallow acid amides, and wax alkane acid amides. and combinations thereof.

The wax may include a fatty acid ester. These fatty acid esters include glyceryl monostearate, glyceryl distearate, glyceryl tristearate, ethylene glycol esters of montanic acids, montanic acid glyceryl ester, trimethylolpropane monostearate, sorbitol tristearate, sorbitol distearate, sorbitol monostearate, penta erythritol tetrastearate, pentaerythritol tristearate, pentaerythritol distearate, pentaerythritol monostearate, and combinations thereof.

The wax may include polyolefin wax. Such polyolefin wax may be selected from polyethylene wax, polar polyethylene wax, poly propylene wax, polar polypropylene wax, and combinations thereof.

The wax may include paraffin.

In the preparation of the carbon nanotube masterbatch according to the present invention, when the carbon nanotubes are less than 45% by weight or the wax exceeds 55% by weight based on the total weight of the carbon nanotube masterbatch, mechanical properties of the final product, the electrically conductive polymer composite It is not preferable because there is a concern that physical properties may be deteriorated due to this decrease, and when the amount of carbon nanotubes exceeds 65% by weight or the amount of wax is less than 35% by weight, it is difficult to uniformly disperse the carbon nanotubes in the wax, which is not preferable. Specifically, 50 to 60% by weight of the carbon nanotubes and 40 to 50% by weight of the wax may be based on the total weight of the carbon nanotube masterbatch.

The carbon nanotubes may include single-walled carbon nanotubes, multi-walled carbon nanotubes, or a combination thereof. These carbon nanotubes are flexible while having very high tensile strength along their longitudinal principal axis.

The single-walled carbon nanotube is composed of a single graphite sheet having an inner hollow core, for example, a diameter of 1 to 2 nanometers, an intrinsic thermal conductivity of 200 W/m-K, a tensile strength of 90 GPa or more, and a stiffness of 0.5 Those having TPa or higher can be used. The multi-wall carbon nanotube has a multi-wall composed of at least two graphite sheets having an inner hollow core, and may have, for example, 10 to 100 nanometers.

The carbon nanotube masterbatch may be prepared in the form of pellets by using a single screw extruder, a twin screw extruder, or a combination thereof, and a kneader may also be used in some cases. The single screw extruder or the twin screw extruder may be classified according to the screw used, and those known in the art may be used.

In the present invention, the carbon nanotube masterbatch can be produced after melting and mixing at 30 to 160 ° C. using such an extruder, and it can be produced at a relatively low temperature, which can significantly reduce energy consumption, and has excellent production efficiency. When the melting temperature is less than 30° C., it is difficult to smoothly melt and mix the carbon nanotubes and the wax due to the excessively low temperature, and when the melting temperature exceeds 160° C., manufacturing processability is deteriorated, which is not preferable.

More specifically, it is prepared by melting and mixing 50 to 60% by weight of carbon nanotubes and 40 to 50% by weight of wax based on the total weight of the carbon nanotube masterbatch at 60 to 80 ° C., and the wax may be a fatty acid ester. there is.

Manufacturing method of electrically conductive polymer composite

In the present invention, an electrically conductive polymer composite prepared by melting and mixing 84 to 96% by weight of a polymer resin, 0.1 to 0.5% by weight of an antioxidant, and 3 to 17% by weight of the carbon nanotube masterbatch based on the total weight of the electrically conductive polymer composite. Provides a manufacturing method of.

In the present invention, an electrically conductive polymer composite exhibiting high gloss, improved surface smoothness, and improved black surface color and excellent mechanical properties can be prepared using the carbon nanotube masterbatch prepared above.

The polymer resin is polyester, polyolefin, polyvinyl chloride, polystyrene, rubber-modified polystyrene, polyimide, polyamide, polyetherimide, polycarbonate, polyetherketone, polyetheretherketone, polyaryleneether, polysulfone, It may be selected from polydiphenylsulfide, a copolymer of acrylonitrile and butadiene, thermoplastic polyurethane, polyacetal, and combinations thereof, and may be specifically polyolefin.

The polyolefins include polyethylene (including high density polyethylene (HDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), and linear low density polyethylene (LLDPE)), polypropylene (atactic, syndiotactic and isotactic polypropylenes). Including), and may include polyisobutylene.

If the amount of the polymer resin is less than 84% by weight or greater than 96% by weight based on the total weight of the electrically conductive polymer composite, it is difficult to sufficiently secure the electrically conductive polymer composite or manufacturing processability may deteriorate, which is undesirable.

The antioxidant may be phosphorus-based, phenol-based, amine-based, sulfur-based or phosphite-based. More specifically, 2,6-di-tert-butyl-4-methylphenol (2,6-di-tert-butyl-4-methyl phenol), poly(1,2-dihydro-2,2, 4-trimethylquinoline) [poly(1,2-dihydro-2,2,4-trimethyl quinoline)], tetrakis[methylene(3,5-di-tert-butyl-4-hydroxy-hydrocinnamate)methane [tetrakis [methylene(3,5-di-tert-butyl-4-hydroxy-hydrocinnamate)]methane] or tris(2,4-di-tert-butyl-phenyl)phosphite [tris(2,4-di- tert-butylphenyl) phosphite] can be used.

If the content of antioxidant based on the total weight of the electrically conductive polymer composite is less than 0.1% by weight or exceeds 0.5% by weight, an appropriate antioxidant effect cannot be obtained or the content of the polymer resin or carbon nanotube masterbatch is relatively low. It is difficult to exhibit the effect intended by the invention, which is undesirable.

The carbon nanotube masterbatch is as described above, and is prepared by melting and mixing 45 to 65% by weight of carbon nanotubes and 55 to 35% by weight of wax at 30 to 160 ° C. based on the total weight of the carbon nanotube masterbatch. It may be a nanotube masterbatch, and in detail, 84 to 96% by weight of a polymer resin, 0.1 to 0.5% by weight of an antioxidant, and 3 to 17% by weight of the carbon nanotube masterbatch prepared above, based on the total weight of the electrically conductive polymer composite. It can be prepared by melt mixing.

When the carbon nanotube masterbatch is less than 3% by weight based on the total weight of the electrically conductive polymer composite, it is difficult to achieve the intended effect of the present invention, and when it exceeds 17% by weight, the polymer composite prepared due to the relatively low content of the polymer resin. It is undesirable because other physical properties such as stiffness may be deteriorated.

The electrically conductive polymer composite may be prepared by a single screw extruder, a twin screw extruder, or a combination thereof, and a kneader may also be used in some cases. The single screw extruder or the twin screw extruder may be classified according to the screw used, and those known in the art may be used.

In the present invention, the electrically conductive polymer composite may be prepared by melting and mixing at 160 to 240° C. using such an extruder. When the melting temperature is less than 160° C., smooth melting and mixing is difficult due to the excessively low temperature, and when the melting temperature exceeds 240° C., manufacturing processability is deteriorated, which is not preferable.

Specifically, in the present invention, 84 to 96% by weight of polyolefin, 0.1 to 0.5% by weight of antioxidant, and 3 to 10% by weight of the carbon nanotube masterbatch are melt-mixed with a polymer resin based on the total weight of the electrically conductive polymer composite. At this time, in detail, in the carbon nanotube masterbatch, 50 to 60% by weight of carbon nanotubes and 40 to 50% by weight of wax based on the total weight of the carbon nanotube masterbatch are melted at 60 to 80 ° C. It is prepared by mixing, and the wax may be a fatty acid ester.

In the present invention, the carbon nanotube masterbatch not only replaces the conventional polymer-based carbon nanotube masterbatch, but also can act as a lubricant and a dispersant, so the use of separate lubricants and dispersants can be minimized. That is, the present invention is capable of dispersing carbon nanotubes in a polymer matrix in an electrically conductive polymer composite and minimizing a dispersant and a lubricant for reducing the viscosity of a molten polymer while highly concentrating the carbon nanotubes, thereby providing a carbon nanotube master with a small content. Even using a batch, a polymer composite exhibiting excellent electrical conductivity can be prepared.

Although described with reference to the following examples, the following examples are intended to illustrate the present invention, and the scope of the present invention is not limited to these only.

<Example 1-1>

A premix mixture of 50% carbon nanotubes and 50% ethylene-bis-stearamide is fed into the feeder of the co-rotating twin screw extruder and then into the single screw extruder. The set temperature of the co-rotating twin screw extruder is as follows. Feed section 30-40°C, transport section 130-140°C, melt zone 140-150°C, and die head 150°C. The single screw extruder has 4 heating zones and the temperature is set at 130~150℃. The carbon nanotube masterbatch is pelletized by an air cooling hot cutting method.

<Example 1-2>

A premix mixture of 50% carbon nanotubes and 50% polyethylene wax is fed into the feeder of the co-rotating twin screw extruder and then into the single screw extruder. The set temperatures of the co-rotating twin screw extruder are as follows: feeding section 30-40°C, conveying section 110-120°C, melting zone 120-130°C, and die head 130°C. The single screw extruder has four heating zones and the temperature is set at 110-130°C. The carbon nanotube masterbatch is pelletized by an air cooling hot cutting method.

<Example 1-3>

A premix mixture of 50% carbon nanotubes and 50% pentaerythritol tristearate was fed into a feeder of a co-rotating twin screw extruder and then into a single screw extruder. The set temperatures of the co-rotating twin screw extruder are as follows: feeding section 30-40°C, conveying section 60-70°C, melting zone 70-80°C, and die head 80°C. The single screw extruder has 4 heating zones and the temperature is set at 60~80℃. The carbon nanotube masterbatch is pelletized by an air cooling hot cutting method.

<Example 1-4>

A premix mixture of 50% carbon nanotubes and 50% pentaerythritol distearate is fed into a feeder of a co-rotating twin screw extruder and then into a single screw extruder. The set temperatures of the co-rotating twin screw extruder are as follows: feeding section 30-40°C, conveying section 60-70°C, melting zone 70-80°C, and die head 80°C. The single screw extruder has 4 heating zones and the temperature is set at 60~80℃. The carbon nanotube masterbatch is pelletized by an air cooling hot cutting method.

<Example 1-5>

A premix mixture of 50% carbon nanotubes and 50% pentaerythritol tetrastearate is fed into the feeder of the co-rotating twin screw extruder and then into the single screw extruder. The set temperatures of the co-rotating twin screw extruder are as follows: feeding section 30-40°C, conveying section 60-70°C, melting zone 70-80°C, and die head 80°C. The single screw extruder has 4 heating zones and the temperature is set at 60~80℃. The carbon nanotube masterbatch is pelletized by an air cooling hot cutting method.

<Example 1-6>

A premix mixture of 60% carbon nanotubes and 40% pentaerythritol tetrastearate was fed into the feeder of a co-rotating twin screw extruder and then into a single screw extruder. The set temperatures of the co-rotating twin screw extruder are as follows: feeding section 30-40°C, conveying section 60-70°C, melting zone 70-80°C, and die head 80°C. The single screw extruder has 4 heating zones and the temperature is set at 60~80℃. The carbon nanotube masterbatch is pelletized by an air cooling hot cutting method.

<Example 2-1>

To prepare an electrically conductive polymer composite (composite), the carbon nanotube masterbatch of Example 1-1 was applied to polyethylene. A mixture of 93.8 wt% HDPE, 0.2 wt% antioxidant, and 6 wt% carbon nanotube masterbatch was mixed and pelletized through a co-rotating twin screw extruder. Subsequently, carbon nanotube/HDPE composite specimen samples were prepared using an extruder. The heating temperature was set between 180 and 200 °C from injection to the die head zone.

<Example 2-2>

To prepare an electrically conductive polymer composite, the carbon nanotube masterbatch of Example 1-2 was applied to polyethylene. A mixture of 93.8 wt% HDPE, 0.2 wt% antioxidant, and 6 wt% carbon nanotube masterbatch was mixed and pelletized through a co-rotating twin screw extruder. Subsequently, carbon nanotube/HDPE composite specimen samples were prepared using an extruder. The heating temperature was set between 180 and 200 °C from injection to the die head zone.

<Example 2-3>

To prepare an electrically conductive polymer composite, the carbon nanotube masterbatches of Examples 1-3 were applied to polyethylene. A mixture of 93.8 wt% HDPE, 0.2 wt% antioxidant, and 6 wt% carbon nanotube masterbatch was mixed and pelletized through a co-rotating twin screw extruder. Subsequently, carbon nanotube/HDPE composite specimen samples were prepared using an extruder. The heating temperature was set between 180 and 200 °C from injection to the die head zone.

<Example 2-4>

To prepare electrically conductive polymer composites, the carbon nanotube masterbatches of Examples 1-4 were applied to polyethylene. A mixture of 93.8 wt% HDPE, 0.2 wt% antioxidant, and 6 wt% carbon nanotube masterbatch was mixed and pelletized through a co-rotating twin screw extruder. Subsequently, carbon nanotube/HDPE composite specimen samples were prepared using an extruder. The heating temperature was set between 180 and 200 °C from injection to the die head zone.

<Example 2-5>

To prepare electrically conductive polymer composites, the carbon nanotube masterbatches of Examples 1-5 were applied to polyethylene. A mixture of 93.8 wt% HDPE, 0.2 wt% antioxidant, and 6 wt% carbon nanotube masterbatch was mixed and pelletized through a co-rotating twin screw extruder. Subsequently, carbon nanotube/HDPE composite specimen samples were prepared using an extruder. The heating temperature was set between 180 and 200 °C from injection to the die head zone. In addition, in order to measure mechanical properties, specimens for measuring mechanical properties were prepared through injection molding.

<Example 2-6>

To prepare electrically conductive polymer composites, the carbon nanotube masterbatches of Examples 1-6 were applied to polyethylene. A mixture of 94.8 wt% HDPE, 0.2 wt% antioxidant, and 5 wt% carbon nanotube masterbatch was mixed and pelletized through a co-rotating twin screw extruder. Subsequently, carbon nanotube/HDPE composite specimen samples were prepared using an extruder. The heating temperature was set between 180 and 200 °C from injection to the die head zone. In addition, in order to measure mechanical properties, specimens for measuring mechanical properties were prepared through injection molding.

<Comparative Example 1-1>

A premix mixture of 30% carbon nanotubes and 70% pentaerythritol tetrastearate was fed into the feeder of the co-rotating twin screw extruder and then into the single screw extruder. The set temperatures of the co-rotating twin screw extruder are as follows: feeding section 30-40°C, conveying section 60-70°C, melting zone 70-80°C, and die head 80°C. The single screw extruder has 4 heating zones and the temperature is set at 60~80℃. The carbon nanotube masterbatch is pelletized by an air cooling hot cutting method.

<Comparative Example 2-1>

To prepare an electrically conductive polymer composite, the carbon nanotube masterbatch of Comparative Example 1-1 was applied to polyethylene. A mixture of 89.8 wt% HDPE, 0.2 wt% antioxidant, and 10 wt% carbon nanotube masterbatch was mixed and pelletized through a co-rotating twin screw extruder. Subsequently, carbon nanotube/HDPE composite specimen samples were prepared using an extruder. The heating temperature was set between 180 and 200 °C from injection to the die head zone. In addition, in order to measure mechanical properties, specimens for measuring mechanical properties were prepared through injection molding.

<Experimental Example 1>

A photograph of the carbon nanotube master batch pellets prepared in Examples 1-6 is shown in FIG. 1A, and a photograph of the polymer composite pellets prepared in Examples 2-6 is shown in FIG. 1B.

<Experimental Example 2>

Photographs of the electrically conductive polymer composite sheets prepared in Example 2-6 and Comparative Example 2-1 are shown in FIGS. 2A and 2B , respectively.

2a and 2b, the composite sheet of Example 2-6 prepared using the carbon nanotube master batch pellets according to Example 1-6 was smooth, whereas the carbon nanotube master batch prepared in Comparative Example 1-1 It can be seen that the composite sheet of Comparative Example 2-1 prepared using batch pellets has flow marks on the surface due to excessive wax and is sticky.

<Experimental Example 3>

Table 1 shows the results of measuring the surface resistance of the electrically conductive polymer composite sheets prepared in Examples 2-1 to 2-6 and Comparative Example 2-1 using the ASTM D4496-04 method.

Example 2-1 Example 2-2 Example 2-3 Example 2-4 Example 2-5 Example 2-6 Comparative Example 2-1 Surface resistivity (log10 (Ω/sq)) 7.2 6.1 5.1 4.8 5.4 5.3 5.3

Referring to Table 1 above, when EBS (Example 2-1) and PE Wax (Example 2-2) were used to make a CNT masterbatch in the HDPE matrix, the surface resistances were 10 ^7.2 and 10 ^6.1 Ω/sq, respectively. It can be seen that the dispersion is not good. When pentaerythritol distearate (Examples 2-4) was used as a carrier for the CNT masterbatch, the lowest surface resistance of 10 ^4.8 Ω/sq was exhibited. These results are due to the hydroxyl group of pentaerythritol distearate (Example 2-4), and EBS (Example 2-1), PE Wax (Example 2-2), pentaerythritol tristearate (Example 2-3) and This is because it helped to disperse CNTs in the polymer matrix more than pentaerythritol tetrastearate (Examples 2-5 and 2-6). Surfaces in Examples 2-5, 2-6, and Comparative Example 2-1 Looking at the resistance, it is shown that the amount of lubricant, i.e., wax, in the CNT masterbatch has little effect on the surface resistance of the CNT/HDPE nanocomposite. However, a high content of wax not only degrades the mechanical properties of the composite, but also causes a blooming phenomenon to occur, resulting in sticky or white dots on the surface of the product.

<Experimental Example 4>

Table 2 shows the results of measuring the mechanical properties of the electrically conductive polymer composite sheets prepared in Examples 2-3 to 2-6 and Comparative Example 2-1 using the ASTM D638 method.

sample name Tensile Strength (MPa) Elongation (%) Flexural Strength (MPa) Impact Strength (J/m) Example 2-3 25.40 17.37 18.63 34.72 Example 2-4 26.08 19.36 19.12 33.73 Example 2-5 23.34 20.05 21.38 29.91 Example 2-6 23.83 20.51 21.97 30.50 Comparative Example 2-1 21.47 14.31 19.71 24.61

According to Table 2, as the content of CNT in the CNT masterbatch is reduced from 60wt% (Example 2-6) to 30wt% (Comparative Example 2-1), the tensile strength, flexural strength and impact strength of the electrically conductive polymer composite can be seen to decrease. This is because if the CNT content in the CNT masterbatch is low, the CNT masterbatch must be used to obtain the same surface resistance value in the electrically conductive polymer composite, so the mechanical properties may be deteriorated due to the increased wax content. Therefore, using a CNT content of more than 50wt% in the CNT masterbatch can prevent the reduction of mechanical properties due to wax in the finally manufactured electrically conductive polymer composite, and the wax used can be used as a lubricant and spraying agent. It can effectively disperse the CNTs by acting as an agent.

Claims (12)

As a method for producing a carbon nanotube masterbatch,
It is prepared after melting and mixing 50 to 60% by weight of carbon nanotubes and 40 to 50% by weight of wax at 30 to 150 ° C. based on the total weight of the carbon nanotube masterbatch, and does not include a high-molecular polymer as a carrier,
The wax is ethylene bis stearamide, polyethylene wax, pentaerythritol tetrastearate, pentaerythritol tristearate, pentaerythritol distearate And a method for producing a carbon nanotube masterbatch, characterized in that one selected from the group consisting of combinations thereof. delete According to claim 1,
A method for producing a carbon nanotube masterbatch, characterized in that melting and mixing 60% by weight of carbon nanotubes and 40% by weight of wax based on the total weight of the carbon nanotube masterbatch at 30 to 80 ° C. According to claim 1,
The method of producing a carbon nanotube masterbatch, characterized in that the carbon nanotubes include single-walled carbon nanotubes, multi-walled carbon nanotubes or a combination thereof. According to claim 1,
The carbon nanotube masterbatch is a method for producing a carbon nanotube masterbatch, characterized in that produced in the form of pellets by a single screw extruder, a twin screw extruder, and a combination thereof. A method for producing an electrically conductive polymer composite,
Based on the total weight of the electrically conductive polymer composite, 93.8 to 94.8% by weight of a polymer resin, 0.1 to 0.2% by weight of an antioxidant, and 5 to 6% by weight of the carbon nanotube masterbatch according to claim 1 are melt-mixed at 180 to 200 ° C. A method for producing an electrically conductive polymer composite, characterized in that it is produced. According to claim 6,
The polymer resin is polyester, polyolefin, polyvinyl chloride, polystyrene, rubber-modified polystyrene, polyimide, polyamide, polyetherimide, polycarbonate, polyetherketone, polyetheretherketone, polyaryleneether, polysulfone, A method for producing an electrically conductive polymer composite, characterized in that it is selected from polydiphenylsulfide, copolymers of acrylonitrile and butadiene, thermoplastic polyurethanes, polyacetals, and combinations thereof. delete delete According to claim 1,
A method for producing a carbon nanotube masterbatch, characterized in that melting and mixing 50% by weight of carbon nanotubes and 50% by weight of wax based on the total weight of the carbon nanotube masterbatch at 30 to 150 ° C. According to claim 1,
A method for producing a carbon nanotube masterbatch, characterized in that melting and mixing 50% by weight of carbon nanotubes and 50% by weight of wax based on the total weight of the carbon nanotube masterbatch at 30 to 80 ° C. According to claim 6,
The method of manufacturing an electrically conductive polymer composite, characterized in that the polymer resin is polyolefin.

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