High-thermal-conductivity carbon powder composite material and preparation method thereof
The carbon nanospiral rings are grown by combining nickel acetate reaction precipitation with hydrothermal method and chemical vapor deposition method, which solves the problems of low conductivity and insufficient interface bonding strength of carbon nanotube composites, and achieves the improvement of high conductivity, compression and thermal conductivity.
Patent Information
- Application Number
- CN202510181339.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-19
- Publication Date
- 2025-05-13
AI Technical Summary
In actual applications, existing carbon nanotube composite materials have problems such as low conductivity, insufficient interface bonding strength, and easy detachment and slippage, which limits their application in fields of high conductivity and high strength requirements.
By combining the reaction precipitation of nickel acetate and the hydrothermal method, it is mounted on defects and active sites inside and on the surface of the carbon nanotubes, increasing the steric hindrance and surface polarity, and preventing direct contact and agglomeration between the carbon nanotubes. At the same time, a carbon nanohelical ring is grown inside the carbon nanotube by chemical vapor deposition method to form a three-dimensional interpenetrating network structure.
The dispersion and conductivity of composite materials are improved, the electron transfer rate and the compressive, bending and impact resistance of the material are improved, and the thermal conductivity is enhanced.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of carbon powder composite materials, in particular to a high thermal conductivity carbon powder composite material and a preparation method thereof. Background Art
[0002] With the rapid development of modern science and technology, high thermal conductivity materials play an indispensable role in many fields. As an important member of high thermal conductivity carbon powder composite materials, carbon nanotube composite materials have shown great potential in thermal management due to the ultra-high theoretical thermal conductivity of carbon nanotubes, attracting widespread attention from scientific researchers. For example, in electronic devices, as chip performance improves, the heat generated increases dramatically, and efficient heat dissipation materials are urgently needed. Carbon nanotube composite materials have become one of the ideal candidates.
[0003] However, this material has some obvious shortcomings in practical applications. Although carbon nanotubes have good intrinsic conductivity, the connection between carbon nanotubes in the composite material system is not ideal, and there is a large amount of contact resistance. This frequently blocks the transmission of electrons within the material, causing the overall conductivity to be far lower than expected, severely limiting its application in electromagnetic shielding materials, flexible circuits and other electronic devices that have strict requirements on conductivity. Although carbon nanotubes themselves have high strength and modulus, when compounded with the matrix, due to the insufficient interfacial bonding strength between the two, under the action of external forces, the carbon nanotubes and the matrix are prone to debonding and slipping. This results in the inability of composite materials to effectively carry and transfer loads, and the mechanical properties are difficult to meet the strict requirements of material strength and toughness in fields such as aerospace and automotive manufacturing. Summary of the invention
[0004] The object of the present invention is to provide a high thermal conductivity carbon powder composite material and a preparation method thereof, so as to solve the problems existing in the prior art.
[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a high thermal conductivity carbon powder composite material, wherein the high thermal conductivity carbon powder composite material is prepared by combining carbon nanotubes with nickel acetate through reaction precipitation and hydrothermal method to prepare composite carbon nanotubes, and then growing carbon nano spiral rings inside the carbon nanotubes through chemical vapor deposition method, and the specific steps are: (1) Dispersing 10 parts of carbon nanotubes and 0.1-1.2 parts of nickel nitrate in 100 parts of deionized water, adding 5-30 parts of sodium hydroxide aqueous solution at a rate of 2 drops / s at 70-80°C and 100 rpm, stirring for 10-30 minutes, transferring to a reactor, heating to 120°C, reacting for 12-24 hours, centrifuging in a centrifuge for 10 minutes, collecting the solid, washing with deionized water three times, and drying in an oven at 40-50°C for 10-18 hours to obtain composite carbon nanotubes; (2) The composite carbon nanotubes are placed in a magnetic boat, placed in the center of a high-temperature tube furnace, argon is introduced, the temperature is raised to 400°C, and calcined for 10 to 60 minutes. The temperature is then raised to 500°C, the argon flow rate is kept constant, hydrogen is introduced, and the reaction is carried out for 30 to 100 minutes. The temperature is again raised to 800°C, and a carbon source gas is introduced. The flow ratio of argon and hydrogen is adjusted, and the growth is carried out for 20 to 180 minutes. The carbon source gas and hydrogen are turned off, the argon flow rate is adjusted to 80 sccm, and the temperature is cooled to room temperature to obtain a high thermal conductivity carbon powder composite material.
[0006] Furthermore, the diameter of the carbon nanotubes in step (1) is 10-40 nm.
[0007] Furthermore, the concentration of sodium hydroxide in the sodium hydroxide aqueous solution in step (1) is 1 mol / L.
[0008] Furthermore, the rotation speed of the centrifuge in step (1) is 3000 rpm.
[0009] Furthermore, in step (2), the flow rate of the argon gas is 250 sccm.
[0010] Furthermore, the flow rate of hydrogen in step (2) is 180 sccm.
[0011] Furthermore, the carbon source gas in step (2) is any one of methane, acetylene and ethylene.
[0012] Furthermore, the flow rate of the carbon source gas is 100 sccm.
[0013] Furthermore, in step (2), the flow ratio of the carbon source gas to the adjusted argon gas and hydrogen gas is (0.8-1):1.7:1.1.
[0014] Compared with the prior art, the beneficial effects achieved by the present invention are: The invention combines nickel acetate with a hydrothermal method through reaction precipitation, and carries it on defects and active sites inside and on the surface of carbon nanotubes through covalent bond bonding, thereby increasing steric hindrance and surface polarity, preventing direct contact and agglomeration between carbon nanotubes, thereby improving the dispersibility of the composite material, and cooperating with the conductivity of nickel oxide to accelerate the electron transmission rate, reduce the resistance of the reaction, and improve the conductivity. In addition, the nickel oxide can provide active sites for the subsequent growth of carbon nano spiral rings, accelerate the growth rate, and reduce the cost. Then, the chemical vapor deposition method is used to grow carbon nano spiral rings inside the carbon nanotubes, so that the carbon nanotube walls are connected to each other to form a three-dimensional interpenetrating network structure. When the material is impacted by an external force, the impact force can be uniformly transmitted and dispersed through the three-dimensional network structure, and local stress concentration can be reduced, thereby significantly improving the material's compression resistance, bending resistance and impact resistance, and forming a multi-directional conductive path, reducing anisotropy, and improving conductivity. At the same time, a larger specific surface area can more effectively transmit heat, so that the heat can be quickly diffused in the material, thereby improving the thermal conductivity of the composite material. DETAILED DESCRIPTION
[0015] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0016] In order to more clearly illustrate the method provided by the present invention, the following examples are used to describe in detail the various index testing methods of the high thermal conductivity carbon powder composite materials prepared in the following examples are as follows: Tensile strength: The same mass of the embodiment and the comparative example was mixed with a polymer with 10 times the mass to prepare a test specimen for curing, and the test was performed according to ASTM D3039.
[0017] Shear strength: The same mass of the embodiment and the comparative example was mixed with a polymer with 10 times the mass to prepare a test specimen for curing, and the test was performed according to ASTM D5379.
[0018] Comprehensive thermal conductivity: Take the same mass of the embodiment and the comparative example, mix and solidify with a polymer with 10 times the mass to prepare a sample, and use a thermal resistance tester to test the comprehensive thermal conductivity of the sample.
[0019] Volume resistivity: Take the same mass of the embodiment and the comparative example, mix them with a high molecular polymer of 10 times the mass and solidify them to prepare a sample, use a low resistance tester to measure the resistance of the sample and calculate the volume resistivity.
[0020] Example 1 (1) 10 parts of carbon nanotubes with a diameter of 10 nm and 0.1 parts of nickel nitrate were dispersed in 100 parts of deionized water, and 5 parts of 1 mol / L sodium hydroxide aqueous solution were added at a rate of 2 drops / s under stirring at 70°C and 100 rpm. After stirring for 10 minutes, the mixture was transferred to a reactor, heated to 120°C, reacted for 12 hours, placed in a centrifuge at 3000 rpm for 10 minutes, and the solid was collected, washed with deionized water 3 times, and dried in an oven at 40°C for 10 hours to obtain composite carbon nanotubes; (2) The composite carbon nanotubes were placed in a magnetic boat, placed in the center of a high-temperature tube furnace, argon was introduced at a flow rate of 250 sccm, the temperature was raised to 400°C, and calcined for 10 minutes. The temperature was then raised to 500°C, the argon flow rate was kept unchanged, hydrogen was introduced at a flow rate of 180 sccm, and the reaction was carried out for 30 minutes. The temperature was raised to 800°C again, methane was introduced at a flow rate of 100 sccm, the argon flow rate was adjusted to 170 sccm, and the hydrogen flow rate was adjusted to 110 sccm. The growth was carried out for 20 minutes, the methane and hydrogen were turned off, the argon flow rate was adjusted to 80 sccm, and the temperature was cooled to room temperature to obtain a high thermal conductivity carbon powder composite material.
[0021] Example 2 (1) 10 parts of carbon nanotubes with a diameter of 25 nm and 0.65 parts of nickel nitrate were dispersed in 100 parts of deionized water, and 17.5 parts of 1 mol / L sodium hydroxide aqueous solution were added dropwise at a rate of 2 drops / s under stirring at 75°C and 100 rpm. After stirring for 20 minutes, the mixture was transferred to a reactor, heated to 120°C, reacted for 18 hours, placed in a centrifuge at 3000 rpm for 10 minutes, the solid was collected, washed with deionized water three times, and dried in an oven at 45°C for 14 hours to obtain composite carbon nanotubes; (2) The composite carbon nanotubes were placed in a magnetic boat, placed in the center of a high-temperature tube furnace, argon was introduced at a flow rate of 250 sccm, the temperature was raised to 400°C, and calcined for 35 minutes. The temperature was then raised to 500°C, the argon flow rate was kept unchanged, hydrogen was introduced at a flow rate of 180 sccm, the reaction was carried out for 65 minutes, the temperature was raised to 800°C again, acetylene was introduced at a flow rate of 100 sccm, the argon flow rate was adjusted to 192 sccm, and the hydrogen flow rate was adjusted to 124 sccm, the growth was carried out for 100 minutes, the acetylene gas and hydrogen were turned off, the argon flow rate was adjusted to 80 sccm, and the temperature was cooled to room temperature to obtain a high thermal conductivity carbon powder composite material.
[0022] Example 3 (1) 10 parts of carbon nanotubes with a diameter of 40 nm and 1.2 parts of nickel nitrate were dispersed in 100 parts of deionized water, and 30 parts of 1 mol / L sodium hydroxide aqueous solution were added dropwise at a rate of 2 drops / s under stirring at 80°C and 100 rpm. After stirring for 30 minutes, the mixture was transferred to a reactor, heated to 120°C, reacted for 24 hours, placed in a centrifuge at 3000 rpm for 10 minutes, the solid was collected, washed with deionized water 3 times, and dried in an oven at 50°C for 18 hours to obtain composite carbon nanotubes; (2) The composite carbon nanotubes were placed in a magnetic boat, placed in the center of a high-temperature tube furnace, argon was introduced at a flow rate of 250 sccm, the temperature was raised to 400°C, and calcined for 60 minutes. The temperature was then raised to 500°C, the argon flow rate was kept unchanged, hydrogen was introduced at a flow rate of 180 sccm, the reaction was carried out for 100 minutes, the temperature was raised to 800°C again, ethylene was introduced at a flow rate of 100 sccm, the argon flow rate was adjusted to 213 sccm, and the hydrogen flow rate was adjusted to 138 sccm, the growth was carried out for 180 minutes, the ethylene and hydrogen were turned off, the argon flow rate was adjusted to 80 sccm, and the temperature was cooled to room temperature to obtain a high thermal conductivity carbon powder composite material.
[0023] Comparative Example 1 (1) A carbon nanotube with a diameter of 25 nm was placed in a magnetic boat, which was placed in the center of a high-temperature tube furnace, and argon gas was introduced at a flow rate of 250 sccm. The temperature was raised to 400°C and calcined for 35 minutes. The temperature was then raised to 500°C, the argon flow rate was kept unchanged, and hydrogen gas was introduced at a flow rate of 180 sccm. The reaction was carried out for 65 minutes. The temperature was raised to 800°C again, acetylene was introduced at a flow rate of 100 sccm, and the argon flow rate and hydrogen flow rate were adjusted to 192 sccm and 124 sccm, respectively. The carbon source gas and hydrogen were turned off, and the argon flow rate was adjusted to 80 sccm. After cooling to room temperature, a high thermal conductivity carbon powder composite material was obtained.
[0024] Comparative Example 2 (1) 10 parts of carbon nanotubes with a diameter of 25 nm and 0.65 parts of nickel nitrate were dispersed in 100 parts of deionized water, and 17.5 parts of a 1 mol / L citric acid aqueous solution were added dropwise at a rate of 2 drops / s under stirring at 75°C and 100 rpm, and stirred until a viscous gel was formed, and then dried at 120°C, calcined at 500°C for 2 h, and crushed to obtain composite carbon nanotubes; (2) The composite carbon nanotubes were placed in a magnetic boat, placed in the center of a high-temperature tube furnace, and argon was introduced at a flow rate of 250 sccm. The temperature was raised to 400°C and calcined for 35 minutes. The temperature was then raised to 500°C, the argon flow rate was kept unchanged, and hydrogen was introduced at a flow rate of 180 sccm. The reaction was carried out for 65 minutes. The temperature was raised to 800°C again, acetylene was introduced at a flow rate of 100 sccm, and the argon flow rate was adjusted to 192 sccm and the hydrogen flow rate to 124 sccm. The growth was carried out for 100 minutes. The carbon source gas and hydrogen were turned off, and the argon flow rate was adjusted to 80 sccm. After cooling to room temperature, a high thermal conductivity carbon powder composite material was obtained.
[0025] Comparative Example 3 (1) 10 parts of carbon nanotubes with a diameter of 25 nm and 0.65 parts of nickel nitrate were dispersed in 100 parts of deionized water, and 17.5 parts of 1 mol / L sodium hydroxide aqueous solution were added dropwise at a rate of 2 drops / s under stirring at 75°C and 100 rpm. After stirring for 20 minutes, the mixture was transferred to a reactor, heated to 120°C, reacted for 18 hours, placed in a centrifuge at 3000 rpm for 10 minutes, the solid was collected, washed with deionized water three times, and dried in an oven at 45°C for 14 hours to obtain composite carbon nanotubes; (2) The composite carbon nanotubes were placed in a magnetic boat, placed in the center of a high-temperature tube furnace, argon gas was introduced at a flow rate of 250 sccm, the temperature was raised to 400°C, and calcined for 35 minutes, then the temperature was raised to 500°C, the argon flow rate was kept unchanged, hydrogen gas was introduced at a flow rate of 180 sccm, the reaction was carried out for 65 minutes, the temperature was raised to 800°C again, the hydrogen gas was turned off, acetylene gas was introduced at a flow rate of 100 sccm, the growth was carried out for 100 minutes, the acetylene gas was turned off, the argon flow rate was adjusted to 80 sccm, and the temperature was cooled to room temperature to obtain a high thermal conductivity carbon powder composite material.
[0026] Comparative Example 4 (1) 10 parts of carbon nanotubes with a diameter of 25 nm and 0.65 parts of nickel nitrate were dispersed in 100 parts of deionized water, and 17.5 parts of 1 mol / L sodium hydroxide aqueous solution were added at a rate of 2 drops / s under stirring at 75°C and 100 rpm. After stirring for 20 minutes, the mixture was transferred to a reactor, heated to 120°C, reacted for 18 hours, and centrifuged at 3000 rpm for 10 minutes in a centrifuge. The solid was collected, washed three times with deionized water, and dried in an oven at 45°C for 14 hours to obtain a high thermal conductivity carbon powder composite material.
[0027] Effect example Table 1 below shows the performance analysis results of the high thermal conductivity carbon powder composite materials using Examples 1 to 3 of the present invention and Comparative Examples 1 to 4.
[0028] Table 1
[0029] From the comparison of the experimental data of Examples 1, 2, and 3 with Comparative Examples 1 and 2, it can be found that nickel acetate is combined with the hydrothermal method through reaction precipitation, and is covalently bonded to the defects and active sites inside and on the surface of the carbon nanotubes, which increases the steric hindrance and surface polarity, prevents direct contact and agglomeration between the carbon nanotubes, improves the dispersibility of the composite material, cooperates with the conductivity of nickel oxide, accelerates the electron transfer rate, reduces the resistance of the reaction, and improves the conductivity; from the comparison of the experimental data of Examples 1, 2, and 3 with Comparative Examples 3 and 4, it can be found that by using the chemical vapor deposition method, carbon nano spiral rings are grown inside the carbon nanotubes, so that the carbon nanotube walls are connected to each other to form a three-dimensional interpenetrating network structure. When the material is impacted by external force, the impact force can be uniformly transmitted and dispersed through the three-dimensional network structure, reducing local stress concentration, thereby significantly improving the material's compression, bending and impact resistance, and forming a multi-directional conductive path, reducing anisotropy, and improving conductivity. At the same time, a larger specific surface area can more effectively transfer heat, so that heat can be quickly diffused in the material, and the thermal conductivity of the composite material is improved.
[0030] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and scope of the equivalent elements of the claims be included in the invention. Any marking in a claim should not be considered as limiting the claim to which it relates.
Claims
1. A high thermal conductivity carbon powder composite material, characterized in that: The high thermal conductivity carbon powder composite material is prepared by combining carbon nanotubes with nickel acetate through reaction precipitation and hydrothermal method to prepare composite carbon nanotubes, and then growing carbon nano spiral rings inside the carbon nanotubes through chemical vapor deposition method. The specific steps are: (1) Dispersing 10 parts of carbon nanotubes and 0.1-1.2 parts of nickel nitrate in 100 parts of deionized water, adding 5-30 parts of sodium hydroxide aqueous solution at a rate of 2 drops / s at 70-80°C and 100 rpm, stirring for 10-30 minutes, transferring to a reactor, heating to 120°C, reacting for 12-24 hours, centrifuging in a centrifuge for 10 minutes, collecting the solid, washing with deionized water three times, and drying in an oven at 40-50°C for 10-18 hours to obtain composite carbon nanotubes; (2) The composite carbon nanotubes are placed in a magnetic boat, placed in the center of a high-temperature tube furnace, argon is introduced, the temperature is raised to 400°C, and calcined for 10 to 60 minutes. The temperature is then raised to 500°C, the argon flow rate is kept constant, hydrogen is introduced, and the reaction is carried out for 30 to 100 minutes. The temperature is again raised to 800°C, and a carbon source gas is introduced. The flow ratio of argon and hydrogen is adjusted, and the growth is carried out for 20 to 180 minutes. The carbon source gas and hydrogen are turned off, the argon flow rate is adjusted to 80 sccm, and the temperature is cooled to room temperature to obtain a high thermal conductivity carbon powder composite material.
2. The high thermal conductivity carbon powder composite material according to claim 1, characterized in that: The diameter of the carbon nanotubes in step (1) is 10-40 nm.
3. The high thermal conductivity carbon powder composite material according to claim 1, characterized in that: The concentration of sodium hydroxide in the sodium hydroxide aqueous solution in step (1) is 1 mol / L.
4. The high thermal conductivity carbon powder composite material according to claim 1, characterized in that: The rotation speed of the centrifuge in step (1) is 3000 rpm.
5. The high thermal conductivity carbon powder composite material according to claim 1, characterized in that: The flow rate of the argon gas in step (2) is 250 sccm.
6. The high thermal conductivity carbon powder composite material according to claim 1, characterized in that: The flow rate of hydrogen in step (2) is 180 sccm.
7. The high thermal conductivity carbon powder composite material according to claim 1, characterized in that: The carbon source gas in step (2) is any one of methane, acetylene and ethylene.
8. The high thermal conductivity carbon powder composite material according to claim 8, characterized in that: The flow rate of the carbon source gas is 100 sccm.
9. The high thermal conductivity carbon powder composite material according to claim 1, characterized in that: In step (2), the flow ratio of the carbon source gas to the adjusted argon gas and hydrogen gas is (0.8-1):1.7:1.1.