KR20250038254A - PAEK-based conductive composite with improved dispersibility including talc and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a PAEK-based conductive composite having improved dispersibility including talc, and more particularly, to a PAEK-based conductive composite having improved dispersibility including talc, comprising: a matrix including a first polymer and a second polymer having a higher viscosity than that of the first polymer; carbon nanotubes dispersed in the matrix; and talc having an average particle size of 1 to 15 ㎛ dispersed in the matrix, wherein the talc is included in an amount greater than 1 time and less than 3 times the weight of the carbon nanotubes, and two or more particles having different average particle sizes are included in a weight ratio of 8 to 6:2 to 4, so as to have a uniform surface resistance of 10 ³ to 10 ⁹ Ω/sq.

Description

PAEK-based conductive composite with improved dispersibility including talc and manufacturing method thereof

The present invention relates to a PAEK-based conductive composite with improved dispersibility including talc and a method for producing the same, wherein carbon nanotubes and talc are dispersed as fillers in a polymer having a viscosity difference to have more uniform surface resistance.

Polymers have excellent properties such as lightness, various moldability, chemical resistance, etc., and are easy to color and have beautiful appearances, so they are widely used in packaging materials, building materials, electrical appliance housings, household goods, automobile interior parts, etc. However, unlike metals, polymers are electrically insulating, so they have the property of accumulating static electricity generated by friction, etc. for a long time, and various obstacles can be caused by discharge, attraction, and repulsion due to the charged static electricity. In order to prevent electrostatic obstacles of polymers, static electricity dispersion or radiation that removes, neutralizes, and leaks the generated charge is essential.

To this end, a conductive polymer composite is manufactured by dispersing a conductive additive in a polymer matrix. The conductive polymer composite can be classified into an electromagnetic shielding polymer, an ESD (static dissipative) polymer, and an antistatic polymer depending on the range of surface resistance, and carbon black, carbon fiber, etc. with high electrical conductivity can be applied as the conductive filler.

However, their use is limited due to slugging and dust generation, and they have problems such as low impact strength and low formability of the material, which limits market expansion.

Therefore, recently, as an alternative for the high-end market, technology is being developed for electrostatic-dissipative polymers that utilize carbon nanotubes (CNTs), such as multi-wall carbon nanotubes (MWCNTs) and single-wall carbon nanotubes (SWCNTs), as conductive fillers, which can provide electrostatic dissipative performance with only a small amount of addition due to their high conductivity.

For example, Japanese Patent Application Publication No. 2010-540687 (Patent Document 0001) discloses the production of a master batch based on carbon nanotubes and then introducing the master batch into a thermoplastic and/or elastomeric polymer composition to produce a conductive composite.

However, as in Patent Document 0001, there is a limit to the uniform dispersion of carbon nanotubes throughout the polymer when only producing carbon nanotubes as a master batch, making it difficult to uniformize the surface resistance of the composite. In addition, since the carbon nanotubes should preferably be included in an amount of 10 to 20 wt% when producing the master batch, the economic feasibility is also low.

Accordingly, efforts are being made to uniformize the surface resistance of the composite while reducing the carbon nanotube content by including fillers other than carbon nanotubes.

For example, Japanese Patent Laid-Open No. 2010-031107 (Patent Document 0002) discloses a thermoplastic resin that includes fillers such as talc and mica, and fillers such as graphite or metal flakes in addition to carbon nanotubes, thereby reducing the amount of carbon nanotubes filled to 1.3 to 2.5 mass%, while having a volume resistivity of 10 ⁸ Ω cm to 10 ¹³ Ω cm and exhibiting an antistatic function.

However, Patent Document 0002 has a total content of fillers of 15 to 35 mass%, which is high, and inorganic fillers are included only for dimensional stability, machinability, and low expansion, but does not show uniform dispersion of fillers by a combination of carbon nanotubes and inorganic fillers and uniform surface resistance resulting therefrom.

Therefore, the present invention aims to provide a composite having uniform surface resistance and a method for manufacturing the same by further including talc together with carbon nanotubes as a filler to improve the dispersibility of the carbon nanotubes.

Japanese Patent Publication No. 2010-540687 (Published on December 24, 2010) Japanese Patent Publication No. 2010-031107 (Published on February 12, 2010)

The present invention aims to provide a PAEK-based conductive composite having improved dispersibility by including talc together with carbon nanotubes to improve the uniform dispersion of carbon nanotubes and thereby have uniform surface resistance, in order to complement the prior art.

In addition, the present invention seeks to provide a method for producing a PAEK-based conductive composite with improved dispersibility including talc.

In order to solve the above-mentioned problem, in one aspect, the present invention provides a PAEK-based conductive composite having improved dispersibility including talc, comprising: a matrix including a first polymer and a second polymer having a higher viscosity than that of the first polymer; carbon nanotubes dispersed in the matrix; and talc having an average particle size of 1 to 15 ㎛ dispersed in the matrix; wherein the talc is included in an amount greater than 1 to 3 times the weight of the carbon nanotubes, and two or more particle groups having different average particle sizes are included in a weight ratio of 8 to 6: 2 to 4, and characterized in that the composite has a uniform surface resistance of 10 ³ to 10 ⁹ Ω/sq.

In one embodiment, a PAEK-based conductive composite having improved dispersibility including talc, characterized in that the coefficient of variation of surface resistance of the composite is less than 0.049.

In one embodiment, the talc may include a particle group (A) having an average particle size of 1 to 5 ㎛ and a particle group (B) having an average particle size of 8 to 15 ㎛, and the particle group (A) and the particle group (B) may be included in a weight ratio of 8 to 6: 2 to 4 or 2 to 4: 8 to 6.

In one embodiment, the carbon nanotubes may be included in an amount of 0.75 wt% or more and less than 5 wt% based on the total weight of the conductive composite.

In one embodiment, the talc may be included in an amount greater than 0.75 wt% and less than or equal to 10 wt% based on the total weight of the complex.

In one embodiment, the difference in melt flow index between the first polymer and the second polymer may be 40 to 70 cm ³ /10 min at 380 ℃/5 kg, and the difference in melt viscosity between the first polymer and the second polymer may be 200 to 1000 Pa s at 400 ℃ and a shear rate of 100/s, and preferably, the first polymer and the second polymer are blended in a ratio of 25 to 80: 20 to 75 or 20 to 75: 25 to 80, and preferably, the first polymer and/or the second polymer is selected from the group consisting of polyaryletherketone, polyetheretherketone, polyetherketoneketone, polyetherketone, polyethersulfone, polyacetal, polyacrylic, polycarbonate, polystyrene, polyester, polyamide, polyamideimide, polyarylate, polyurethane, It may be at least one selected from polyarylsulfone, polyarylene sulfide, polyvinyl chloride, polyetherimide, polyimide, and polytetrafluoroethylene.

In addition, the present invention, in another aspect, provides a method for producing a PAEK-based conductive composite having improved dispersibility including talc, characterized by including the steps of: producing a masterbatch by melt-mixing a first polymer, carbon nanotubes, and talc in a first extruder; and producing a composite by mixing the masterbatch with a second polymer having a higher viscosity than that of the first polymer in a second extruder.

In one embodiment, the masterbatch may contain talc in an amount greater than 1 to less than 3 times the weight of carbon nanotubes.

In one embodiment, the talc may include a particle group (A) having an average particle size of 1 to 5 ㎛ and a particle group (B) having an average particle size of 8 to 15 ㎛, and the particle group (A) and the particle group (B) may be included in a weight ratio of 8 to 6: 2 to 4 or 2 to 4: 8 to 6.

In one embodiment, the masterbatch:second polymer can be blended in a weight % ratio of 30 to 80:20 to 70.

In one embodiment, after the step of manufacturing the complex, an annealing step may be further included.

The conductive composite of the present invention comprises carbon nanotubes and talc, and by controlling the average particle size of the talc and the content ratio of the talc to the carbon nanotubes, the carbon nanotubes are uniformly dispersed on the matrix, so that the entire composite has uniform surface resistance.

In addition, the conductive composite of the present invention can improve crystallinity through an annealing process.

FIG. 1 is a drawing explaining a surface resistance measurement method according to one embodiment of the present invention.
FIG. 2 is a graph showing the surface resistance distribution of an unannealed composite manufactured according to one embodiment of the present invention.
FIG. 3 is a graph showing the surface resistance distribution of an annealed composite manufactured according to one embodiment of the present invention.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In general, the nomenclature used herein is well known and commonly used in the art.

Whenever it is said throughout this specification that a part "includes" a component, this does not exclude other components, but rather includes other components, unless otherwise stated.

Throughout this specification, the terms “-times” in “1x” and “3x” do not only mean a value that is exactly -times based on a specific value, but also include a range that a person of ordinary skill in the art would recognize as equivalent.

Throughout this specification, “particle population” means a group of particles falling within a specified size range.

The present invention relates to a PAEK-based conductive composite having improved dispersibility including talc, comprising: a matrix including a first polymer and a second polymer having a higher viscosity than that of the first polymer; carbon nanotubes and talc, wherein the content ratio of the carbon nanotubes and talc, the average particle size of the talc, and the content ratio between talcs having different average particle sizes are optimized to uniformly disperse the carbon nanotubes in the composite, thereby having a uniform surface resistance of 10 ³ to 10 ⁹ Ω/sq.

Specifically, the present invention, in one aspect, provides a PAEK-based conductive composite having improved dispersibility including talc, comprising: a matrix including a first polymer and a second polymer having a higher viscosity than that of the first polymer; carbon nanotubes dispersed in the matrix; and talc having an average particle size of 1 to 15 ㎛ dispersed in the matrix; wherein the talc is included in an amount greater than 1 to 3 times the weight of the carbon nanotubes, and two or more particle groups having different average particle sizes are included in a weight ratio of 8 to 6: 2 to 4, and characterized in that the composite has a uniform surface resistance of 10 ³ to 10 ⁹ Ω/sq.

Carbon nanotubes exhibit extremely high rigidity and strength due to the sp2 bonding between carbon-carbon atoms, and exhibit extremely low electrical resistance due to their one-dimensional structure and the unique electrical structure of graphite.

The present invention comprises the carbon nanotubes in an amount of 0.75 wt% or more and less than 5 wt% based on the total weight of the composite. If the carbon nanotubes are included in an amount of less than 0.75 wt%, sufficient electrical conductivity cannot be exhibited, so that the surface resistance increases to 10 ¹⁰ Ω/sq or more, and if they are included in an amount of 5 wt% or more, the carbon nanotubes cannot be uniformly dispersed due to agglomeration, and the degree of increase in conductivity is not great compared to the amount added, so that economic feasibility decreases.

In the present invention, the carbon nanotube may be a single-walled (SW), double walled (DW), or multi-walled carbon nanotube (MWNT), and may have a shape such as armchair, zigzag, or chiral, and all of these may be applied without any particular limitation.

In the present invention, the talc is included in an amount of 1 to 3 times greater than the weight of the carbon nanotube, has an average particle size of 1 to 15 ㎛, and two or more particle groups having different average particle sizes are included in a weight ratio of 8 to 6: 2 to 4.

Specifically, when the talc is included in an amount of 1 to 3 times the weight of the carbon nanotubes, the miscibility between the talc and the carbon nanotubes is not high, so that there is talc that does not mix with the carbon nanotubes but aggregates, thereby reducing the dispersibility of the carbon nanotubes or not greatly improving the dispersibility. Therefore, the talc has an average particle size of 1 to 15 ㎛, but includes two or more particle groups having different average particle sizes in a weight ratio of 8 to 6: 2 to 4, thereby increasing the miscibility of the talc and carbon nanotubes due to different particle sizes and suppressing aggregation between the talc particles, thereby improving the dispersion uniformity of the carbon nanotubes in the matrix.

That is, when the talc has an average particle size of 1 to 15 ㎛, and two or more particle groups having different average particle sizes are outside the weight ratio range of 8 to 6: 2 to 4, the mixing property of the talc and carbon nanotubes due to the difference in average particle size is significantly reduced, while the agglomeration between the talc particles is increased, so that the uniform dispersion of the carbon nanotubes is not affected or may rather be reduced.

More specifically, the talc includes a particle group (A) having an average particle size of 1 to 5 μm and a particle group (B) having an average particle size of 8 to 15 μm, and the particle group (A) and the particle group (B) are included in a weight ratio of 8 to 6: 2 to 4 or 2 to 4: 8 to 6, so that the carbon nanotubes mixed with the talc can be more uniformly dispersed on the matrix due to the difference in size between the particles and the difference in mixing ratio between different particles, thereby increasing the uniformity of the surface resistance of the composite.

In addition, when the carbon nanotubes are included in an amount of 0.75 wt% or more and less than 5 wt% based on the total weight of the composite, preferably, the talc is included in an amount of more than 0.75 wt% and less than 10 wt% based on the total weight of the composite. When the talc is included in an amount of 0.75 wt% or less, the effect of adding talc is minimal, and when it exceeds 10 wt%, the mechanical properties of the composite may be improved, but rather, the electrical conductivity of the carbon nanotubes may be reduced, so that even if the carbon nanotubes are uniformly dispersed, a composite having sufficient surface resistance cannot be manufactured.

In the present invention, the matrix is in a state where first polymer and second polymer having different viscosities are mixed or formed as layers, and the difference in melt volume flow rate (MVR) between the first polymer and the second polymer is 40 to 70 cm3/10 min at 380°C/5 kg.

Melt Volume-flow Rate (MVR) is a type of melting index, which represents the volume (cm3/min) extruded for 10 minutes at a constant temperature and a specified force (weight), and indicates the fluidity of a polymer material. The higher the molecular weight, the lower the MVR. In other words, the higher the MVR, the better the flowability and the smaller the molecular weight. In the present invention, by including a first polymer and a second polymer having different viscosities, that is, a second polymer having a higher viscosity than that of the first polymer, in a matrix together to control the flowability, carbon nanotubes are uniformly dispersed in the matrix, and when the composite is manufactured by an extrusion process, the shape of the composite can be maintained without collapsing until cooling after extrusion.

Additionally, the difference in melting viscosity between the first polymer and the second polymer is 200 to 1000 Pa·s at 400°C and a shear rate of 100/s.

Melt viscosity refers to the viscosity of a substance in a molten state, and the melt viscosity can vary depending on the molecular structure, degree of polymerization, etc., and is an important factor directly related to formability. The difference in melt viscosity between the first polymer and the second polymer of the present invention is 200 to 1000 Pa·s at 400° C. and a shear rate of 100/s, so as to enable uniform dispersion and extrusion molding of carbon nanotubes. If the viscosity is out of the above range, the carbon nanotubes may not be uniformly dispersed, thus failing to exhibit uniform dispersion resistance, or the shape may not be maintained and collapse after extrusion due to excessive flowability.

These first polymer and second polymer may be in the same or different forms, selected from the form of pellets and powders, and may be selected by considering the type of polymer, molecular weight, MVR, composite manufacturing method, etc.

Additionally, the first polymer and the second polymer may be the same or different thermoplastic resins.

The first polymer and the second polymer are thermoplastic resins, and examples thereof include polycarbonate resin, polypropylene resin, polyamide resin, aramid resin, aromatic polyester resin, polyolefin resin, polyester carbonate resin, polyphenylene ether resin, polyphenylene sulfide resin, polysulfone resin, polyether sulfone resin, polyarylene resin, cycloolefin resin, polyetherimide resin, polyacetal resin, polyvinyl acetal resin, polyketone resin, polyaryl sulfone, polyarylene sulfide, polyether ketone resin, polyether ketone ketone resin, polyether ether ketone resin, polyaryl ether ketone resin, polyaryl ketone resin, polyether nitrile resin, polytetrafluoroethylene, polyvinyl chloride, polyarylate, polyamide imide, polyester, polystyrene, polyacrylic, polyurethane, It may be at least one selected from the group consisting of polybenzimidazole resin, polyparabonic acid resin, aromatic alkenyl compound, methacrylic acid ester, acrylic acid ester, and vinyl cyanide compound, preferably a PAEK-based polymer, and more preferably a polyetheretherketone resin or a polyetherketoneketone resin. However, the first polymer and the second polymer are not limited thereto, and may be appropriately selected depending on the intended use.

In addition, in the conductive composite, the first polymer and the second polymer are mixed in a weight % ratio of 25 to 80:20 to 75 or 20 to 75:25 to 80. If the mixing ratio is out of the above range, it may be difficult to manufacture the conductive composite or the carbon nanotubes may not be uniformly included in an appropriate amount, which may cause a decrease in surface resistance.

The surface resistance of the complex of the present invention can be measured by the ANSI/ESD S11.13 (2Pin) or ANSI/ESD S11.11 (circular) method, and is 10 ³ to 10 ⁹ Ω/sq, preferably 10 ⁶ to 10 ⁹ Ω/sq, and the variation coefficient of the surface resistance is less than 0.049, preferably 0.001 or more and less than 0.049, so that it has high uniformity.

In addition, the manufactured composite can further improve dimensional stability and physical properties by lowering the shrinkage rate of the final product through annealing, and the annealed composite has a surface resistance of 10 ³ to 10 ⁹ Ω/sq, preferably 10 ⁶ to 10 ⁹ Ω/sq.

The composite of the present invention can be applied to various fields exhibiting conductive, electromagnetic shielding, ESD, and antistatic performance.

As another example, the present invention provides a method for producing a PAEK-based conductive composite having improved dispersibility including talc, the method including the steps of: producing a masterbatch by melt-mixing a first polymer, carbon nanotubes, and talc in a first extruder; and producing a composite by mixing the masterbatch with a second polymer having a higher viscosity than that of the first polymer in a second extruder.

In the above present invention, the step of manufacturing a masterbatch is a step of manufacturing a masterbatch in which a first polymer, carbon nanotubes, and talc are melt-mixed in an extruder to concentrate the carbon nanotubes, which are active substances, and the inorganic filler mixed therewith, and the masterbatch contains carbon nanotubes and talc in an amount greater than 1 and less than 3 times the weight of the carbon nanotubes, and the polymer is included as the remainder excluding the carbon nanotubes and talc, thereby maintaining the working efficiency of the masterbatch and manufacturing the carbon nanotubes containing talc in an aggregated solid form to improve dispersibility and ensure that the carbon nanotubes and talc are sufficiently included.

Specifically, the carbon nanotubes are included in an amount of 0.75 wt% or more and less than 5 wt% based on the total weight of the composite, the talc is included in an amount of more than 1 time and less than 3 times the weight of the carbon nanotubes, preferably, the average particle size is 1 to 15 ㎛, and two or more particle groups having different average particle sizes are included in a weight ratio of 8 to 6: 2 to 4, thereby increasing the mixing property of the talc and carbon nanotubes due to different average particle sizes and suppressing aggregation between the talc particles, thereby improving the dispersion uniformity of the carbon nanotubes in the matrix.

More specifically, the talc includes a particle group (A) having an average particle size of 1 to 5 μm and a particle group (B) having an average particle size of 8 to 15 μm, and the particle group (A) and the particle group (B) are included in a weight ratio of 8 to 6: 2 to 4 or 2 to 4: 8 to 6, so that the carbon nanotubes mixed with the talc can be more uniformly dispersed on the matrix due to the difference in size between the particles and the difference in mixing ratio between different particle groups.

Preferably, the talc is included in an amount of more than 0.75 wt% and less than 10 wt% based on the total weight of the complex.

The next step is a step of manufacturing a composite by mixing the manufactured masterbatch with a second polymer having a higher viscosity than that of the first polymer in a second extruder. The masterbatch and the second polymer can be melt-blended or dry-blended, and the masterbatch: second polymer are mixed in a weight % ratio of 30 to 80: 20 to 70.

Above masterbatch: If the blending ratio of the second polymer is outside the range of 30 to 80:20 to 70 based on weight %, and the blending ratio of the masterbatch is less than 30 and the blending ratio of the second polymer is more than 70, an excessive amount of polymer is blended with respect to the CNT content, so that a conductive composite having a sufficient CNT content cannot be manufactured, and thus proper surface resistance characteristics cannot be exhibited.

In this case, it may be considered to increase the CNT content of the masterbatch to be compounded to 5 wt% or more in order to ensure that sufficient CNT content is included in the conductive composite. However, when the masterbatch is manufactured to contain 5 wt% or more of CNT content, strand breakage (molten composite strand discharged through the die) occurs between operations, making it difficult or impossible to manufacture the masterbatch, and thus making it impossible to manufacture the conductive composite.

In addition, when the blending ratio of the masterbatch exceeds 80 and the blending ratio of the second polymer is less than 20, the second polymer is included in the conductive composite at a relatively low level, and thus the effect of improving the physical properties due to the viscosity difference between the first polymer and the second polymer cannot be exhibited.

In this way, the master batch and the second polymer are mixed in a weight % ratio of 30 to 80: 20 to 70, and the flowability is controlled due to the difference in melt volume flow index and melt viscosity formed by the polymers having different viscosities, so that the carbon nanotubes and talc can be uniformly dispersed on the matrix including the first polymer and the second polymer, and the effect of adding talc is maximized, so that the composite can have more uniform surface resistance.

Additionally, the present invention may further include an annealing step.

The above annealing step is to heat the manufactured composite at a predetermined temperature, thereby controlling the degree of crystallinity and the range of surface resistance. Accordingly, the annealed composite can further improve dimensional stability and physical properties by reducing shrinkage, and the annealed composite has a surface resistance of 10 ³ to 10 ⁹ Ω/sq, preferably 10 ⁶ to 10 ⁹ Ω/sq.

<Example>

1. Manufacturing of conductive composites

(Example 1 - Example 2, Comparative Example 1 - Comparative Example 3) Manufacturing of conductive composite

First, the primary polymer was made into a pellet-shaped low-viscosity PEEK (VESTAKEEP 2000G evonik) with an MVR of 70 cm ³ /10 min, dried at 130 ° C. for more than 4 hours, and the pellet-shaped low-viscosity PEEK, carbon nanotubes (BT-1001M LG Chemical), and talc (KC-5000L (3.5 μm), KCNAP-400BK (11 μm)) were extruded in a twin-screw extruder (temperature conditions in the order of Head > 1~7 Zone: 365-365-365-365-370-375-375-360 ° C.) and then pelletized to manufacture a masterbatch (M/B) containing carbon nanotubes (CNT) and talc.

Thereafter, the above-mentioned manufactured masterbatch and the secondary polymer, PEEK (VESTAKEEP 4000G evonik) in pellet form with high viscosity and MVR 11 cm ³ /10 min, were mixed at a weight ratio (weight % ratio) of 6:4 and mixed and extruded using an extruder under the same conditions as those for manufacturing the above-mentioned masterbatch, thereby manufacturing a conductive composite.

The conductive composites manufactured above were manufactured in Examples 1 to 2 and Comparative Examples 1 to 3 according to conditions such as the average particle size of the added talc, the content, and the mixing ratio of talc having different average particle sizes, and are shown in Table 1 below.

However, in Table 1, the mixture (A:B) represents the mixture of the above-mentioned talc KC-5000L (3.5 μm) and KCNAP-400BK (11 μm) in a weight ratio (A:B), where A represents the mixture ratio of KC-5000L (3.5 μm) and B represents the mixture ratio of KCNAP-400BK (11 μm).

(Example 3 - Example 4, Comparative Example 4 - Comparative Example 6) Annealed conductive composite

Each of the conductive composites manufactured above (Examples 1 to 2 and Comparative Examples 1 to 3) was annealed at 230°C for 16 hours, and described as Examples 3 to 4 and Comparative Examples 4 to 6.

The conductive composites of Examples 3 to 4 and Comparative Examples 4 to 6 are shown in Table 2 below.

2. Analysis

The surface resistance and crystallinity of the conductive composite manufactured above were measured according to the following methods and are shown in Tables 1 and 2, and the surface resistance distribution is shown in Figures 2 and 3.

<Surface resistance measurement method>

Fig. 1 shows a surface resistance measurement area according to one embodiment of the present invention. A 10 cm × 30 cm sample was divided into 15 measurement points (3 × 5) and the surface resistance was measured for 15 points in the outer direction based on the roll. Specifically, a 2-pin type surface resistance measuring device (PRS-801B, Prostat Corporation) was used to measure in the horizontal direction.

<Crystallization degree>

Using DSC (Differential Scanning Calorimetry), the temperature was increased from 30 ℃ to 430 ℃ at a rate of 10 ℃/min, and measurements were taken.

Through Table 1 and Fig. 2, when the weight ratio of CNTs and talc in the conductive composite is 1:3, and talc having an average particle size of 3.5 ㎛ and talc having an average particle size of 11 ㎛ are mixed in a ratio of 3:7 or 7:3 (Examples 1 and 2), it can be seen that the average surface resistance is about 10 ⁷ Ω/sq and the coefficient of variation is 0.045 and 0.047, respectively, indicating that the CNTs are uniformly distributed, thereby exhibiting uniform surface resistance.

On the other hand, when talc particles having average particle sizes of 3.5 ㎛ and 11 ㎛ were mixed in a ratio of 5:5 (Comparative Example 3), the average surface resistance was approximately 10 ⁷ Ω/sq, but the coefficient of variation was 0.07, indicating that the uniformity of the CNT distribution within the conductive composite decreased, and thus the uniformity of the surface resistance also decreased.

In addition, when the weight ratio of CNT and talc in the conductive composite was 1:1, the coefficient of variation was 0.064 or higher in both the case where talc particles having average particle sizes of 3.5 ㎛ and 11 ㎛ were mixed in a ratio of 5:5 (Comparative Example 2) and the case where only talc having an average particle size of 3.5 ㎛ was used, indicating that the uniformity of the surface resistance of the conductive composite was reduced.

From the above results, it can be seen that the uniformity of the CNT distribution in the conductive composite and the resulting uniformity of the surface resistance are affected by the content ratio of CNT and talc, the average particle size of the talc, and the mixing ratio of talc having different average particle sizes.

Through the above Table 2 and Fig. 3, it can be seen that the CNT distribution and surface resistance of the annealed conductive composite are similar to those of the conductive composite before annealing, and that the crystallinity increases by annealing.

Claims (13)

A matrix comprising a first polymer and a second polymer having a higher viscosity than that of the first polymer;
Carbon nanotubes dispersed in the above matrix; and
Containing talc having an average particle size of 1 to 15 ㎛ dispersed in the above matrix;
The above talc is included in an amount of 1 to 3 times the weight of the carbon nanotube, and two or more particle groups having different average particle sizes are included in a weight ratio of 8 to 6: 2 to 4.
A PAEK conductive composite having improved dispersibility including talc, characterized by having a uniform surface resistance of 10 ³ to 10 ⁹ Ω/sq.
In paragraph 1,
A PAEK-based conductive composite having improved dispersibility including talc, characterized in that the coefficient of variation of the surface resistance of the composite is less than 0.049.
In the first paragraph,
The above talc includes a particle group (A) with an average particle size of 1 to 5 ㎛ and a particle group (B) with an average particle size of 8 to 15 ㎛.
A PAEK-based conductive composite having improved dispersibility including talc, characterized in that it comprises the particle group (A) and the particle group (B) in a weight ratio of 8 to 6: 2 to 4 or 2 to 4: 8 to 6.
In the first paragraph,
A PAEK-based conductive composite having improved dispersibility including talc, characterized in that the carbon nanotubes are contained in an amount of 0.75 wt% or more and less than 5 wt% based on the total weight of the conductive composite.
In the first paragraph,
A PAEK-based conductive composite having improved dispersibility including talc, characterized in that the talc is contained in an amount of more than 0.75 wt% and less than 10 wt% based on the total weight of the composite.
In the first paragraph,
The difference in melt flow index between the first polymer and the second polymer is 40 to 70 cm ³ /10 min at 380 ℃/5 kg,
A PAEK-based conductive composite having improved dispersibility including talc, characterized in that the difference in melting viscosity between the first polymer and the second polymer is 400°C and the shear rate is 200 to 1000 Pa·s at 100/s.
In the first paragraph,
A PAEK-based conductive composite having improved dispersibility including talc, characterized in that the first polymer and the second polymer are blended in a ratio of 25 to 80:20 to 75 or 20 to 75:25 to 80.
In the first paragraph,
A PAEK-based conductive composite having improved dispersibility including talc, characterized in that the first polymer and/or the second polymer is at least one selected from the group consisting of polyaryletherketone, polyetheretherketone, polyetherketoneketone, polyetherketone, polyethersulfone, polyacetal, polyacrylic, polycarbonate, polystyrene, polyester, polyamide, polyamideimide, polyarylate, polyurethane, polyarylsulfone, polyarylene sulfide, polyvinyl chloride, polyetherimide, polyimide and polytetrafluoroethylene.
A step of producing a masterbatch by melting and mixing a first polymer, carbon nanotubes, and talc in a first extruder; and
A method for producing a PAEK-based conductive composite having improved dispersibility including talc, characterized by comprising the step of producing a composite by mixing the masterbatch with a second polymer having a higher viscosity than that of the first polymer in a second extruder.
In Article 9,
A method for producing a PAEK-based conductive composite having improved dispersibility by including talc, characterized in that the masterbatch contains talc in an amount of 1 to 3 times the weight of carbon nanotubes.
In Article 9,
A method for manufacturing a PAEK-based conductive composite having improved dispersibility, including talc, characterized in that the talc comprises a particle group (A) having an average particle size of 1 to 5 ㎛ and a particle group (B) having an average particle size of 8 to 15 ㎛, and the particle group (A) and the particle group (B) are included in a weight ratio of 8 to 6: 2 to 4 or 2 to 4: 8 to 6.
In Article 9,
The above masterbatch: A method for producing a PAEK-based conductive composite having improved dispersibility including talc, characterized in that the second polymer is mixed in a weight % ratio of 30 to 80: 20 to 70.
In Article 9,
A method for producing a PAEK-based conductive composite having improved dispersibility including talc, characterized in that after the step of producing the above composite, an annealing step is further included.