Conductive modified carbon nanotube resin and preparation method thereof

Abstract

The invention discloses conductive modified carbon nanotube resin and a preparation method thereof, and relates to the technical field of carbon nanotube resin.The conductive modified carbon nanotube resin is prepared from 8%-15% of carbon nanotube master batch and 85%-92% of resin through mixed plasmid; the carbon nano tube master batch is obtained by mixing modified carbon nano tube powder and resin according to a ratio of (4-5): 6; the resin is any one of PPS (polyphenylene sulfite), PC (polycarbonate), TPU (thermoplastic polyurethane) and PP (polypropylene); the carbon nano tube powder is obtained through chemical vapor deposition, a fluidized bed is used as a reaction device, in the fluidized bed, natural gas passes through a catalyst particle bed layer to enable catalyst particles to be in a suspended state, full contact and reaction between gas and solid are achieved, the carbon nano tube powder is generated, the diameter of the carbon nano tube powder is 5-10 nm, and the tube length of the carbon nano tube powder is 25-50 microns; the catalyst is prepared by compounding an iron-based catalyst, a cobalt-based catalyst and a cocatalyst according to a ratio of 1: 2.5: 0.01.

Description

Technical Field

[0001] The invention relates to the technical field of carbon nanotube resins, in particular to a conductive modified carbon nanotube resin and a preparation method thereof. Background Art

[0002] As a one-dimensional nanomaterial, carbon nanotubes are light in weight, have perfectly connected hexagonal structures, and have many extraordinary mechanical, electrical, and chemical properties. In recent years, with the in-depth research on carbon nanotubes and nanomaterials, their broad application prospects have been continuously revealed. The conductivity of carbon nanotubes is 1,000 times that of copper, and can be used as a new type of efficient conductive agent in plastics to make conductive plastics.

[0003] However, existing technologies have the problems of difficulty in adding carbon nanotubes to plastics, unstable performance and high cost, which are specifically reflected in:

[0004] 1. In the prior art, carbon nanotube powder is directly mixed with resin, and the mixture is re-granulated by a twin-screw granulator to generate carbon nanotube plastic particles. The existing problems are: the density of carbon nanotubes is extremely low, and they are easy to scatter during processing, polluting the environment and causing equipment to short-circuit; carbon nanotubes are difficult to disperse evenly, resulting in unstable performance of carbon nanotube plastics; carbon nanotube resin has poor interface compatibility, which increases production costs.

[0005] 2. The existing technology directly mixes carbon nanotube powder with resin, and then re-granulates it through a twin-screw granulator after internal mixing to generate low-concentration carbon nanotube plastic masterbatch; the low-concentration carbon nanotube plastic masterbatch is then mixed with resin, and the mixture is re-granulated through a twin-screw granulator to generate carbon nanotube plastic particles; the existing problems are: a) the internal mixing time is long, the cost is high, and the efficiency is low; b) the low-concentration carbon nanotube plastic masterbatch has a narrow application range, and the required addition amount of low-concentration carbon nanotube plastic masterbatch is as high as 40% to 60%, which seriously restricts other modifications of carbon nanotube plastic particle processing and has high cost. Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] In view of the deficiencies of the prior art, the present invention provides a conductive modified carbon nanotube resin and a preparation method thereof, which solves the problems of difficulty in adding carbon nanotubes to plastics, unstable performance and high cost.

[0008] (II) Technical solution

[0009] To achieve the above-mentioned purpose, the present application provides a conductive modified carbon nanotube resin, which is obtained by mixing 8% to 15% of carbon nanotube masterbatch and 85% to 92% of resin; the carbon nanotube masterbatch is obtained by mixing modified carbon nanotube powder and resin in a ratio of 4 to 5:6; the resin is any one of PPS, PC, TPU, and PP.

[0010] Preferably, the carbon nanotube powder is obtained by chemical vapor deposition, using a fluidized bed as a reaction device. In the fluidized bed, natural gas passes through a catalyst particle bed to place the catalyst particles in a suspended state, thereby achieving sufficient contact and reaction between gas and solid to generate carbon nanotube powder. The carbon nanotube powder has a diameter of 5 to 10 nm and a tube length of 25 to 50 μm.

[0011] Preferably, the catalyst is an iron-based catalyst, a cobalt-based catalyst and a promoter in a ratio of 1:2.5:0.01, the iron-based catalyst is Al2O3 / Fe, the cobalt-based catalyst is Al2O3 / Co; the promoter is praseodymium; wherein Al2O3 is used as a catalyst carrier, and the specific surface area and pore size of the catalyst carrier are 290 m 2 / g~320m 2 / g and 3.0~3.8nm.

[0012] Preferably, the catalyst addition amount is 1%.

[0013] Preferably, the natural gas is ordinary bottled natural gas, which is obtained by removing HS through concentrated sodium hydroxide and then drying; the natural gas includes 95% methane, 3% carbon dioxide, and 2% hydrocarbon impurities, such as ethane and propane.

[0014] Preferably, the catalyst is regenerated by air oxidation, gasification, and hydrogenation of the deposited carbon to restore the catalyst activity.

[0015] Preferably, the modified carbon nanotube powder is obtained by mixing carbon nanotube powder with polyethylene glycol modification and a coupling agent after the carbon nanotube powder is treated with plasma.

[0016] Preferably, the modified carbon nanotubes are used as conductive fillers and the resin is used as a flexible substrate, and the conductive modified carbon nanotube resin is prepared by mixing plasmids; and the surface resistivity of the conductive modified carbon nanotube resin is controlled by controlling the proportion of the conductive filler.

[0017] Preferably, graphite and modified carbon nanotubes are used as conductive fillers.

[0018] Preferably, the modified carbon nanotube powder and resin are granulated by a twin-screw granulator to generate carbon nanotube masterbatch with a carbon nanotube powder concentration of 40% to 45%, and the carbon nanotube masterbatch and resin are mixed and granulated by a twin-screw granulator to generate conductive plastic with controllable surface resistivity.

[0019] To achieve the above object, the present application provides a method for preparing a conductive modified carbon nanotube resin, comprising the following steps: Step 1: Based on a fluidized bed and natural gas, carbon nanotube powder is generated under the catalysis of a catalyst; Step 2: modifying the carbon nanotube powder to destroy the entanglement and bonding state of the carbon nanotube fibers to obtain modified carbon nanotube powder; Step 3: The modified carbon nanotube powder and the resin are re-granulated by a twin-screw granulator to generate carbon nanotube masterbatch, wherein the carbon nanotube powder concentration in the carbon nanotube masterbatch is 40% to 45%; Step 4: Mix the carbon nanotube masterbatch and the resin, and generate the conductive modified carbon nanotube resin through a twin-screw granulator. Preferably, carbon nanotube masterbatch is used as a conductive filler, and a conductive plastic with controllable surface resistivity is obtained by controlling the proportion of the conductive filler.

[0020] Preferably, the preparation process of the carbon nanotube powder comprises the following steps: Step S11, catalyst activation: placing the catalyst in a constant temperature zone of a fluidized bed reactor for reduction, removing air in the reaction device with nitrogen, heating to a catalyst activation temperature, activating the catalyst under hydrogen conditions and removing impurities therein, and reducing the metal oxides in the catalyst to nano-scale metal particles, providing active sites for subsequent methane decomposition and carbon nanotube growth; Step S12, methane cracking: when the reaction temperature reaches the cracking temperature, natural gas, hydrogen and inert gas are introduced into the fluidized bed reactor, and under the action of the catalyst, methane undergoes a decomposition reaction to generate carbon atoms and hydrogen; Step S13, carbon nanotube growth: the carbon atoms generated by the decomposition are deposited on the surface of the metal particles to form the initial structure of the carbon nanotubes. As the reaction proceeds, the carbon nanotubes gradually grow and extend; Step S14: After the reaction is completed, the reaction gas is turned off and the reactor is cooled, and the generated carbon nanotube products are collected from the reactor; in order to remove impurities and catalyst residues in the product, post-processing steps such as purification, separation and drying operations are performed.

[0021] Preferably, during the preparation process, the catalyst activation temperature is set at 450°C to 500°C, the cracking temperature is set at 600°C to 650°C, and the cracking time is set at 35 minutes.

[0022] Preferably, the volume ratio of natural gas: hydrogen: inert gas is 1:2:5; the total gas flow rate is 200-300 mml / min.

[0023] Preferably, the process of obtaining the modified carbon nanotube powder comprises the following steps: Step S21, dispersion and drying: the untreated carbon nanotube powder is placed in a clean and dry beaker and deionized water is added, and ultrasonic dispersion is performed for 30 minutes; a microporous filtration membrane is used for drying; Step S22, plasma surface modification: placing the dried carbon nanotubes in a reactor, applying a voltage of 28 kV to the electrodes of the reactor, with an output frequency of 9 Hz, to trigger a discharge process, with a discharge time of 10 min, to obtain plasma surface modified carbon nanotubes; Step S23, polyethylene glycol modification: melt-blending the plasma surface-modified carbon nanotubes with polyethylene glycol and a coupling agent for 10 minutes at a processing temperature of 150° C. and a rotation speed of 60 r / min to complete the modification of the carbon nanotubes and obtain modified carbon nanotube powders.

[0024] (III) Beneficial effects

[0025] The present invention provides a conductive modified carbon nanotube resin and a preparation method thereof, which has the following beneficial effects:

[0026] (1) The conductive modified carbon nanotube resin and its preparation method provided by the present invention are as follows: carbon nanotube masterbatch and resin are mixed, and a conductive plastic with controllable surface resistivity is generated by a granulator; the addition amount of carbon nanotube masterbatch is only 8% to 15%, and the surface resistivity can be 10^1Ω to 10^9Ω; the production is simple, the production site of the conductive modified plastic particles is not polluted, the production efficiency is high, the production cost is low, and the comprehensive modification of the plastic particles has extremely high flexibility.

[0027] (2) The conductive modified carbon nanotube resin and preparation method provided by the present invention utilize chemical vapor deposition to obtain carbon nanotube powder. By adjusting the catalyst and reaction conditions, carbon nanopowder with excellent conductive properties is obtained. After modification, the carbon nanopowder is better mixed with the resin to obtain carbon nanotube masterbatch, which effectively increases the use of the carbon nanotube masterbatch. DETAILED DESCRIPTION

[0028] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0029] Preparation Example 1 provides a process for preparing carbon nanotube powder, comprising the following steps: Step S11, catalyst activation: placing the catalyst in a constant temperature zone of a fluidized bed reactor for reduction, removing air in the reaction device with nitrogen, heating to a catalyst activation temperature, activating the catalyst under hydrogen conditions and removing impurities therein, and reducing the metal oxides in the catalyst into nano-scale metal particles, providing active sites for subsequent methane decomposition and carbon nanotube growth; Step S12, methane cracking: when the reaction temperature reaches the cracking temperature, natural gas, hydrogen and inert gas are introduced into the fluidized bed reactor, and under the action of the catalyst, methane undergoes a decomposition reaction to generate carbon atoms and hydrogen; Step S13, carbon nanotube growth: the carbon atoms generated by the decomposition are deposited on the surface of the metal particles to form the initial structure of the carbon nanotubes. As the reaction proceeds, the carbon nanotubes gradually grow and extend; Step S14: After the reaction is completed, the reaction gas is turned off and the reactor is cooled, and the generated carbon nanotube products are collected from the reactor; in order to remove impurities and catalyst residues in the product, post-processing steps such as purification, separation and drying operations are performed.

[0030] It needs to be further explained that, during the preparation process, the catalyst activation temperature was set at 450°C, the cracking temperature was set at 600°C, and the cracking time was set at 35 minutes.

[0031] It needs further explanation that the volume ratio of natural gas: hydrogen: inert gas is 1:2:5; the total gas flow rate is 200mml / min; It needs to be further explained that the catalyst is a compound of an iron catalyst, a cobalt catalyst and a promoter in a ratio of 1:2.5:0.01, the iron catalyst is Al2O3 / Fe, the cobalt catalyst is Al2O3 / Co; the promoter is praseodymium; wherein Al2O3 is used as a catalyst carrier, and the specific surface area and pore size of the catalyst carrier are 290m 2 / g~320m 2 / g and 3.0~3.8nm.

[0032] It needs to be further explained that the catalyst addition amount is 1%.

[0033] It needs to be further explained in the embodiments of the present invention that the natural gas is ordinary bottled natural gas, which is obtained by removing HS through concentrated sodium hydroxide and then drying; the natural gas includes 95% methane, 3% carbon dioxide, and 2% hydrocarbon impurities, such as ethane and propane.

[0034] It needs to be further explained that the catalyst is regenerated by air oxidation, gasification and hydrogenation of the deposited carbon to restore the catalyst activity.

[0035] Explanation: The composition and structural characteristics of the catalyst determine the yield and diameter of carbon nanotubes; the catalyst is reduced with hydrogen to obtain metal particles, and the carrier enables the metal particles to be better dispersed, reducing the particle size of the metal particles and increasing the activity of the metal particles. At the same time, the smaller pores in the carrier increase the saturated vapor volume of carbon vapor, promoting the solidification of carbon vapor, and is conducive to the formation of the concentration required for carbon tube growth; the finer the particle size of the catalyst carrier, the smaller the particle size of the metal particles adsorbed on it, and the finer the grown carbon nanotubes. The ratio of catalyst to carrier must be appropriate. If the proportion of carrier is appropriately increased, the metal ions can be better dispersed, thereby reducing the fusion of metal particles at high temperature, especially the fusion of small particles, so that it can not reduce activity at high temperature. However, when the proportion of carrier is too large, the amount of catalyst loaded on it will be reduced.

[0036] It is explained that adding rare earth metals as co-catalysts to the catalyst can increase the voids in the catalyst, improve the surface area of ​​the catalyst, inhibit the growth of metal particles at high temperatures, and improve the stability of metal particles at high temperatures; the incorporation of very small amounts of precious metals can effectively reduce the diameter of carbon nanotubes.

[0037] Preparation Example 2 is different from Preparation Example 1 in that, in the carbon nanotube powder preparation process, the catalyst activation temperature is set to 475° C., the cracking temperature is set to 625° C., and the total gas flow rate is 250 mml / min.

[0038] Preparation Example 3 is different from Preparation Example 1 in that, in the carbon nanotube powder preparation process, the catalyst activation temperature is set to 500° C., the cracking temperature is set to 650° C., and the total gas flow rate is 300 mml / min.

[0039] Summary: The carbon nanotube powders of Preparation Examples 1 to 3 were characterized by microscopic techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), and programmed temperature reduction (TPR), and the diameter of the obtained carbon nanotubes was 5 to 10 nm, and the tube length of the obtained carbon nanotubes was 25 to 50 μm.

[0040] Preparation Example 4 provides a conductive modified carbon nanotube resin, which is obtained by mixing carbon nanotube masterbatch and resin, including: 8% to 15% of carbon nanotube masterbatch and 85% to 92% of resin; the carbon nanotube masterbatch is obtained by mixing modified carbon nanotube powder and resin in a ratio of 4 to 5:6; the resin is any one of PPS, PC, TPU, and PP.

[0041] It needs to be further explained that the carbon nanotube powder is obtained by chemical vapor deposition, using a fluidized bed as a reaction device. In the fluidized bed, natural gas passes through a catalyst particle bed to put the catalyst particles in a suspended state, achieving sufficient contact and reaction between gas and solid to generate carbon nanotube powder. The carbon nanotube powder has a diameter of 5 to 10 nm and a tube length of 25 to 50 μm.

[0042] It needs to be further explained that the modified carbon nanotube powder is obtained by: Step S21, dispersion and drying: the untreated carbon nanotube powder is placed in a clean and dry beaker and deionized water is added, and ultrasonic dispersion is performed for 30 minutes; a microporous filtration membrane is used for drying; Step S22, plasma surface modification: placing the dried carbon nanotubes in a reactor, applying a voltage of 28 kV to the electrodes of the reactor, with an output frequency of 9 Hz, to trigger a discharge process, with a discharge time of 10 min, to obtain plasma surface modified carbon nanotubes; Step S23, polyethylene glycol modification: melt-blending the plasma surface-modified carbon nanotubes with polyethylene glycol and a coupling agent for 10 minutes at a processing temperature of 150° C. and a rotation speed of 60 r / min to complete the modification of the carbon nanotubes and obtain modified carbon nanotube powders.

[0043] It is explained that the molecular weight of the polyethylene glycol is 10,000; the coupling agent is an aluminate coupling agent, which is a substance that can improve the compatibility between the resin and the inorganic filler. Through chemical bonding with the surface of the inorganic filler, the coupling agent can significantly improve the bonding force between the resin and the filler and improve the overall performance of the material.

[0044] It needs to be further explained that the conductive modified carbon nanotube resin is prepared by mixing the modified carbon nanotubes as conductive fillers and the resin as a flexible substrate; and the surface resistivity of the conductive modified carbon nanotube resin is controlled by controlling the proportion of the conductive filler.

[0045] It needs further explanation that graphite and modified carbon nanotubes are used as conductive fillers.

[0046] What needs to be further explained is that the conductive modified carbon nanotube resin is prepared by mixing the modified carbon nanotubes as the conductive filler and the resin (any one of PPS, PC, TPU, PP) as the flexible substrate; and the surface resistivity of the conductive modified carbon nanotube resin is controlled by controlling the proportion of the conductive filler.

[0047] What needs to be further explained is that the modified carbon nanotube powder and resin are granulated by a twin-screw granulator to generate carbon nanotube masterbatch, the concentration of carbon nanotube powder in the carbon nanotube masterbatch is greater than 40%, the carbon nanotube masterbatch and the resin are mixed, and a conductive plastic with controllable surface resistivity is generated by a twin-screw granulator.

[0048] Preparation Example 5: The present application provides a method for preparing a conductive modified carbon nanotube resin, comprising the following steps: Step 1: Based on a fluidized bed and natural gas, carbon nanotube powder is generated under the catalysis of a catalyst; Step 2: modifying the carbon nanotube powder to destroy the entanglement and bonding state of the carbon nanotube fibers to obtain modified carbon nanotube powder; Step 3: The modified carbon nanotube powder and the resin are re-granulated by a twin-screw granulator to generate carbon nanotube masterbatch, wherein the carbon nanotube powder concentration in the carbon nanotube masterbatch is 40% to 45%; Step 4: Mix the carbon nanotube masterbatch and the resin, and generate the conductive modified carbon nanotube resin through a twin-screw granulator. As a conductive filler, a conductive plastic with controllable surface resistivity can be obtained by controlling the proportion of the conductive filler.

[0049] Example 1

[0050] The embodiment of the present invention provides a method for preparing a conductive modified carbon nanotube resin, comprising: The modified carbon nanotube powder and the resin are mixed in a ratio of 4:6 to obtain a carbon nanotube masterbatch with a carbon nanotube powder concentration of 40%; 8% carbon nanotube masterbatch and 92% PPS are mixed to obtain conductive modified carbon nanotube resin, which is marked as conductive modified carbon nanotube PPS.

[0051] Example 2

[0052] The embodiment of the present invention provides a method for preparing a conductive modified carbon nanotube resin, comprising: The modified carbon nanotube powder and the resin are mixed in a ratio of 4:6 to obtain a carbon nanotube masterbatch with a carbon nanotube powder concentration of 40%; 8% carbon nanotube masterbatch and 92% PC are mixed to obtain conductive modified carbon nanotube resin, which is marked as conductive modified carbon nanotube PC.

[0053] Example 3

[0054] The embodiment of the present invention provides a method for preparing a conductive modified carbon nanotube resin, comprising: The modified carbon nanotube powder and the resin are mixed in a ratio of 4:6 to obtain a carbon nanotube masterbatch with a carbon nanotube powder concentration of 40%; 8% carbon nanotube masterbatch and 92% TPU are mixed to obtain conductive modified carbon nanotube resin, which is marked as conductive modified carbon nanotube TPU.

[0055] Example 4

[0056] The embodiment of the present invention provides a method for preparing a conductive modified carbon nanotube resin, comprising: The modified carbon nanotube powder and the resin are mixed in a ratio of 4:6 to obtain a carbon nanotube masterbatch with a carbon nanotube powder concentration of 40%; 8% carbon nanotube masterbatch and 92% PP are mixed to obtain conductive modified carbon nanotube resin, which is marked as conductive modified carbon nanotube PP.

[0057] Summary: Using 40% carbon nanotube masterbatch as conductive filler, 8% and 92% of flexible substrate PPS, PC, TPU, PP were mixed and granulated to obtain the following samples: Conductive modified carbon nanotube PPS, conductive modified carbon nanotube PC, conductive modified carbon nanotube TPU and conductive modified carbon nanotube PP: The surface resistivity of the samples was measured in a constant temperature and humidity environment to avoid the influence of environmental factors on the test results. The resistivity data obtained from the test was recorded and averaged after multiple groups of tests. The resistivities of conductive modified carbon nanotubes PPS, conductive modified carbon nanotubes PC, conductive modified carbon nanotubes TPU and conductive modified carbon nanotubes PP were 2.4×10^7Ω, 9.2×10^7Ω, 4.3×10^8Ω and 1.0×10^9Ω respectively.

[0058] Example 5

[0059] An embodiment of the present invention provides a method for preparing a conductive modified carbon nanotube resin, comprising: mixing carbon nanotube masterbatch with a concentration of 40% and resin PPS, generating a conductive modified carbon nanotube resin by a twin-screw granulator, and when the addition amount of the carbon nanotube masterbatch with a concentration of 40% is 8%, a conductive modified carbon nanotube PPS_1 is obtained.

[0060] Example 6

[0061] An embodiment of the present invention provides a method for preparing a conductive modified carbon nanotube resin, comprising: mixing carbon nanotube masterbatch with a concentration of 40% and resin PPS, generating a conductive modified carbon nanotube resin by a twin-screw granulator, and when the addition amount of the carbon nanotube masterbatch with a concentration of 40% is 13%, a conductive modified carbon nanotube PPS_2 is obtained.

[0062] Example 7

[0063] The embodiment of the present invention provides a method for preparing a conductive modified carbon nanotube resin, comprising: The carbon nanotube masterbatch with a concentration of 40% was mixed with the resin PPS, and a conductive modified carbon nanotube resin was generated by a twin-screw granulator. When the addition amount of the carbon nanotube masterbatch with a concentration of 40% was 15%, the conductive modified carbon nanotube PPS_3 was obtained.

[0064] Example 8

[0065] The embodiment of the present invention provides a method for preparing a conductive modified carbon nanotube resin, comprising: The carbon nanotube masterbatch with a concentration of 45% was mixed with the resin PPS, and a conductive modified carbon nanotube resin was generated by a twin-screw granulator. When the addition amount of the carbon nanotube masterbatch with a concentration of 45% was 13%, the conductive modified carbon nanotube PPS_4 was obtained.

[0066] Example 9

[0067] The embodiment of the present invention provides a method for preparing a conductive modified carbon nanotube resin, comprising: The carbon nanotube masterbatch with a concentration of 45% was mixed with the resin PPS, and a conductive modified carbon nanotube resin was generated by a twin-screw granulator. When the addition amount of the carbon nanotube masterbatch with a concentration of 45% was 15%, the conductive modified carbon nanotube PPS_5 was obtained.

[0068] Summary: Using carbon nanotube masterbatch with a concentration of 40% to 45% as conductive filler, and mixing with flexible substrate PPS at a concentration of 8% to 15%, the following samples were obtained: Conductive modified carbon nanotube PPS_1, conductive modified carbon nanotube PPS_2, conductive modified carbon nanotube PPS_3, conductive modified carbon nanotube PPS_4, conductive modified carbon nanotube PPS_5; The surface resistivity of the samples was measured in a constant temperature and humidity environment, and the resistivity data obtained from the test was recorded. After multiple groups of tests, the average was taken and the corresponding resistivities of the samples were obtained as follows: 7.3×10^2Ω, 5.1×10^2Ω, 2.1×10^2Ω, 7.2×10^1Ω, and 10Ω.

[0069] Furthermore, combined analysis of Examples 1 to 9 revealed that when the nanotube masterbatch with a concentration of 40-45% is mixed with a resin at an addition amount of 8% to 15% and granulated, and the resin is any one of PPS, PC, TPU, and PP, the surface resistivity of the conductive modified carbon nanotube resin obtained is 10^1Ω to 10^9Ω.

[0070] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A conductive modified carbon nanotube resin, obtained by mixing carbon nanotube masterbatch and resin, characterized in that: include: 8% to 15% carbon nanotube masterbatch and 85% to 92% resin; The carbon nanotube masterbatch is obtained by mixing modified carbon nanotube powder and resin in a ratio of 4 to 5:

6.

2. The conductive modified carbon nanotube resin according to claim 1, characterized in that: The resin is any one of PPS, PC, TPU and PP.

3. The conductive modified carbon nanotube resin according to claim 2, characterized in that: The carbon nanotube powder is obtained by chemical vapor deposition, using a fluidized bed as a reaction device. In the fluidized bed, natural gas passes through a catalyst particle bed to put the catalyst particles in a suspended state, achieving sufficient contact and reaction between gas and solid to generate carbon nanotube powder. The carbon nanotube powder has a diameter of 5 to 10 nm and a tube length of 25 to 50 μm.

4. The conductive modified carbon nanotube resin according to claim 3, characterized in that: The catalyst is prepared by mixing an iron-based catalyst, a cobalt-based catalyst and a promoter in a ratio of 1:2.5:0.

01. The iron-based catalyst is Al2O3 / Fe, the cobalt-based catalyst is Al2O3 / Co; the promoter is praseodymium; wherein Al2O3 is used as a catalyst carrier, and the specific surface area and pore size of the catalyst carrier are 290 m 2 / g~320m 2 / g and 3.0~3.8nm.

5. The conductive modified carbon nanotube resin according to claim 3, characterized in that: The catalyst is regenerated by air oxidation, gasification and hydrogenation of deposited carbon to restore catalyst activity.

6. The conductive modified carbon nanotube resin according to claim 4, characterized in that: The modified carbon nanotube powder is obtained by mixing the carbon nanotube powder with polyethylene glycol modification and a coupling agent after the carbon nanotube powder is treated with plasma.

7. The conductive modified carbon nanotube resin according to claim 3, characterized in that: The modified carbon nanotube powder and resin are granulated by a twin-screw granulator to generate carbon nanotube masterbatch with a carbon nanotube powder concentration of 40% to 45%. The carbon nanotube masterbatch and resin are mixed and granulated by a twin-screw granulator to generate conductive plastic with controllable surface resistivity.

8. A method for preparing a conductive modified carbon nanotube resin, for preparing the conductive modified carbon nanotube resin according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: Based on a fluidized bed and natural gas, carbon nanotube powder is generated under the catalysis of a catalyst; Step 2: modifying the carbon nanotube powder to destroy the entanglement and bonding state of the carbon nanotube fibers to obtain modified carbon nanotube powder; Step 3: The modified carbon nanotube powder and the resin are re-granulated by a twin-screw granulator to generate carbon nanotube masterbatch, wherein the carbon nanotube powder concentration in the carbon nanotube masterbatch is 40% to 45%; Step 4: The carbon nanotube masterbatch and the resin are mixed and a conductive modified carbon nanotube resin is generated by a twin-screw granulator.

9. The method for preparing the conductive modified carbon nanotube resin according to claim 8, characterized in that: The preparation process of the carbon nanotube powder comprises the following steps: Step S11, catalyst activation: placing the catalyst in a constant temperature zone of a fluidized bed reactor for reduction, removing air in the reaction device with nitrogen, and heating to a catalyst activation temperature, whereby the metal oxides in the catalyst are reduced into nano-scale metal particles, providing active sites for subsequent methane decomposition and carbon nanotube growth; Step S12, methane cracking: when the reaction temperature reaches the cracking temperature, natural gas, hydrogen and inert gas are introduced into the fluidized bed reactor, and under the action of the catalyst, methane undergoes a decomposition reaction to generate carbon atoms and hydrogen; Step S13, carbon nanotube growth: the carbon atoms generated by the decomposition are deposited on the surface of the metal particles to form the initial structure of the carbon nanotubes. As the reaction proceeds, the carbon nanotubes gradually grow and extend; Step S14: After the reaction is completed, the reaction gas is turned off and the reactor is cooled, and the generated carbon nanotube products are collected from the reactor.

10. The method for preparing the conductive modified carbon nanotube resin according to claim 8, characterized in that: The process of obtaining the modified carbon nanotube powder comprises the following steps: Step S21, dispersion and drying: the untreated carbon nanotube powder is placed in a clean and dry beaker and deionized water is added, and ultrasonic dispersion is performed for 30 minutes; a microporous filtration membrane is used for drying; Step S22, plasma surface modification: placing the dried carbon nanotubes in a reactor, applying a voltage of 28 kV to the electrodes of the reactor, with an output frequency of 9 Hz, to trigger a discharge process, with a discharge time of 10 min, to obtain plasma surface modified carbon nanotubes; Step S23, polyethylene glycol modification: melt-blending the plasma surface-modified carbon nanotubes with polyethylene glycol and a coupling agent for 10 minutes at a processing temperature of 150° C. and a rotation speed of 60 r / min to complete the modification of the carbon nanotubes and obtain modified carbon nanotube powders.