CN116970249A - Center radial carbon nanotube framework, composite material, preparation method and application thereof - Google Patents

Center radial carbon nanotube framework, composite material, preparation method and application thereof Download PDF

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CN116970249A
CN116970249A CN202310751615.7A CN202310751615A CN116970249A CN 116970249 A CN116970249 A CN 116970249A CN 202310751615 A CN202310751615 A CN 202310751615A CN 116970249 A CN116970249 A CN 116970249A
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carbon nanotube
central radial
phase
radial carbon
composite material
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么依民
张精精
孙蓉
刘道庆
叶振强
许建斌
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Shenzhen Institute of Advanced Technology of CAS
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Abstract

The invention discloses a central radial carbon nanotube skeleton, a preparation method thereof and application of the central radial carbon nanotube skeleton as a filler in a heat-conducting phase-change composite material. The invention also providesThe heat-conducting phase-change composite material is composed of a filler taking a central radial carbon nano tube skeleton as well as a polymer as a matrix, and has high heat conductivity coefficient, excellent heat storage performance and good structural stability. The heat conduction coefficient of the heat conduction phase change composite material is 0.4W/(m.K) to 5W/(m.K), the phase change latent heat is 120J/g to 270J/g, and the volume resistivity is 5.0x10 ‑4 Ω·cm～2.0×10 ‑1 Omega cm, and no package leakage caused by cold and hot circulation at 20-60 ℃ for 1000 times. The invention solves the problems of low heat conductivity coefficient and easy leakage of the matrix of the traditional heat-conducting phase-change composite material, and has simple preparation method, low cost and wide application.

Description

Center radial carbon nanotube framework, composite material, preparation method and application thereof
Technical Field
The invention belongs to the technical field of preparation of heat-conducting phase-change composite materials, and relates to a central radial carbon nanotube framework, a preparation method and application thereof, a heat-conducting phase-change composite material and a preparation method thereof.
Background
Under the support of the emerging industries such as artificial intelligence, automatic driving, 5G network, internet of things and the like, advanced packaging is developed towards system integration, high speed, high frequency and three-dimensional directions. Miniaturization of electronic products relies on the development of advanced electronic packaging technology, and three-dimensional packaging faces significant structural heat dissipation challenges compared to two-dimensional packaging. Miniaturization and improvement of packaging integration level of electronic devices promote miniaturization, integration and functionalization of electronic products, power density and heat flux density are rapidly increased, and the electronic devices face huge structural heat dissipation challenges, so that stability, reliability and service life of electronic equipment are affected. It is widely recognized in the industry that the bottleneck in future electronic product development is not the hardware itself and the heat dissipation design, but whether an effective heat dissipation material can be prepared. The problem of "heat" becomes a bottleneck that restricts the large-scale application of the next-generation communication and high-power devices. In the new generation of information technology represented by 5G communication, the problem of heat dissipation of high-density heat flow which has been multiplied in the past is increasingly prominent. The packaging design has limited effect, and the problem of heat dissipation is solved more depending on the development of high-performance heat conducting materials.
The thermal interface material with high laminating property and high thermal conductivity is filled at the interface to form a heat conduction path, so that the contact thermal resistance between the surfaces of the materials is greatly reduced. The polymer is light, easy to process and form and excellent in mechanical property, and has become a mainstream electronic packaging material, but the intrinsic thermal conductivity of the polymer is usually very low (-0.1W/(m.K)), and the heat conduction gain of the phase change composite material prepared by blending the filler and the phase change polymer is mainly due to the contribution of the heat conduction filler.
Although significant progress has been made in the study and application of thermally conductive phase change composites, there are still some technical bottlenecks: (1) poor heat transfer capability: the heat conduction of the polymer matrix is limited by the inherent thermal resistance of the polymer, and an effective heat conduction channel is realized between the polymer matrixes by using the filling material, so that the thermal resistance can be reduced, and the thermal conductivity is important to be improved to the maximum extent. (2) poor heat storage performance: when filler materials are introduced into the phase change composite material to increase thermal conductivity, the heat storage properties of the material may be affected, and the filler materials need to be uniformly dispersed and aligned in the composite matrix in order to optimize the heat storage properties. (3) poor package stability: thermally conductive phase change composites may exhibit limitations in terms of package stability, the presence of fillers may affect the stability of the composite, and factors such as filler-to-polymer interactions, particle dispersion, and filler loading may affect the integrity of the composite over time, affecting its performance and durability.
Thus, overcoming these challenges by developing new filler materials, surface modification, advanced manufacturing techniques, and optimizing composite formulations will lead to a wider utilization of thermally conductive phase change composites in a variety of applications.
Disclosure of Invention
The invention aims to solve the problems in the prior art and provide a central radial carbon nanotube skeleton, a preparation method thereof and application of the central radial carbon nanotube skeleton serving as a filler in a heat conduction phase change composite material. The invention also provides a heat-conducting phase-change composite material which is formed by taking the central radial carbon nanotube skeleton as a filler and taking the phase-change polymer as a matrix, and the phase-change composite material not only has high heat conductivity coefficient and excellent heat storage performance, but also has good structural stability.
In order to achieve the above purpose, the invention adopts the following technical scheme:
the first aspect of the present invention provides a central radial carbon nanotube skeleton, the skeleton comprising a central member, and a plurality of unit elements distributed along a circumferential direction of the central member and respectively connected with the central member; a gap is arranged between two adjacent single elements; the central piece is provided with a through hole structure penetrating through the middle piece in the axial direction; each of the unit pieces has a layered porous structure distributed along a circumferential direction of the center piece; the center piece and each of the unit pieces are made of hydroxyl-functionalized multi-walled carbon nanotubes. I.e. the skeleton is centrally radial.
Further, each single element is in a sheet shape, and the plane of the single element in the sheet shape is parallel to the axial direction of the intermediate piece; the diameter of the central radial carbon nanotube skeleton is 10-50 mm; wherein the length of the hydroxyl functional multiwall carbon nanotube is 1-50 μm, and the diameter is 5-80 nm. The hydroxyl functionalized multiwall carbon nanotubes forming the central radial carbon nanotube skeleton further control the structural morphology of the filler skeleton by controlling the formation of ice in the solute suspension by an ice templating method. Preferably, the hydroxyl-functionalized multiwall carbon nanotubes have a length of 1 to 50 μm, for example 1 μm, 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm or 50 μm, etc. Preferably, the hydroxyl-functionalized multiwall carbon nanotubes have a diameter of 5 to 80nm, for example 5nm, 10nm, 20nm, 30nm, 40nm, 60nm or 80nm, etc.
The second aspect of the present invention provides a method for preparing a central radial carbon nanotube scaffold, the method comprising the steps of:
(1) Taking a hydroxyl functionalized multi-wall carbon nano tube, a binder and deionized water as raw materials to obtain a dispersion liquid, and performing ball milling treatment on the dispersion liquid to obtain a uniformly dispersed mixture;
(2) Preparing a circular ring mold, and arranging a gasket at the bottom of the circular ring mold, wherein the gasket is used for fixing a cylindrical mold arranged in the middle of the circular ring mold; adding the mixture into the circular ring mold, freezing by using an ice template method, keeping the cylindrical mold to rotate, and removing the cylindrical mold arranged in the middle of the circular ring mold after freezing; adding the mixture into a gap in the middle of the circular ring die after the cylindrical die is removed, and performing freezing treatment by using an ice template method to obtain a central radial carbon nanotube skeleton precursor;
(3) And carrying out vacuum freeze drying treatment on the precursor of the central radial carbon nanotube skeleton to obtain the central radial carbon nanotube skeleton. In the technical scheme of the invention, the step (1) uses a ball milling mode to prepare the mixture, because the hydroxyl functionalized multi-wall carbon nano tube is prepared by a chemical vapor phase method, the product has a certain degree of agglomeration, and the ball milling can damage the agglomeration to the greatest extent.
Further, the mass ratio of the hydroxyl-functionalized multi-walled carbon nanotubes, the binder and deionized water in the step (1) is 1: (1-20): (5-100); the binder is a water-soluble polymer; preferably, the binder is one or more of polyacrylamide, polyacrylic acid, polyvinyl alcohol, polyoxyethylene, polyvinylpyrrolidone, cellulose derivative and starch-based adhesive. The main function of the addition of the binder in the invention is that the binder can connect adjacent hydroxyl functionalized multi-wall carbon nanotubes, so that the mechanical property of the central radial carbon nanotube skeleton precursor is improved, and the collapse of the central radial carbon nanotube skeleton precursor in the subsequent vacuum freeze drying process is avoided.
Further, the circular ring mould in the step (2) is placed in liquid nitrogen; the diameter of the circular ring mold is 10 mm-50 mm, and the diameter of the cylindrical mold is 2 mm-10 mm. In the technical scheme of the invention, in the ice template method in the step (2), the uniform mixture is added into a circular ring mold, the circular ring mold is placed into liquid nitrogen, the formed different temperature gradients are utilized for freezing treatment, a mechanical arm is adopted to keep the cylindrical mold rotating, the cylindrical mold in the middle of the circular ring mold is pulled out after freezing is finished, the uniform mixture is added into a gap in the middle of which the cylindrical mold is removed again, freezing treatment is carried out again by using the ice template method, and the size of the central radial carbon nanotube skeleton is controlled. Preferably, the diameter of the circular ring mold is 10mm to 50mm, for example, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm or 50mm, etc. Preferably, the diameter of the cylindrical mold is 2mm to 10mm, for example, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, or the like.
Further, the temperature of the vacuum freeze drying in the step (3) is-80 ℃ to-20 ℃, the time is 12h to 72h, and the vacuum pressure is-60 Pa to-10 Pa. In the technical scheme of the invention, the ice crystal in the precursor of the central radial carbon nanotube skeleton is removed by using a vacuum freeze-drying technology in the step (3) to obtain the central radial carbon nanotube skeleton. Preferably, the vacuum freeze-drying temperature is-80 ℃ to-20 ℃, for example, -80 ℃, -70 ℃, -60 ℃, -50 ℃, -40 ℃, -30 ℃ or-20 ℃ and the like. In this temperature range, the removal of ice crystals in the central radial carbon nanotube skeleton precursor is facilitated. Preferably, the vacuum freeze-drying time is 12h to 72h, for example, 12h, 15h, 19h, 24h, 37h, 48h, 55h, 63h or 72h, etc. Preferably, the vacuum freeze-drying vacuum pressure is-60 Pa to-10 Pa, for example, -60Pa, -55Pa, -50Pa, -46Pa, -33Pa, -25Pa, -15Pa or-10 Pa, etc.
As a preferable technical scheme of the preparation method of the central radial carbon nanotube skeleton, the method comprises the following steps: (1) The multi-wall carbon nano tube (length is 1-50 μm, diameter is 5-80 nm), binder and deionized water according to the mass ratio of 1: (1-20): (5-100), preparing a dispersion liquid containing hydroxyl functionalized multi-wall carbon nano tubes, a binder and deionized water, and performing ball milling treatment to obtain a uniformly dispersed mixture; (2) Adding the uniform mixture into a circular ring mold (with the diameter size range of 10-50 mm), adding a gasket at the bottom for fixing a middle cylindrical mold (with the diameter size range of 2-10 mm), freezing by using an ice template method, keeping the cylindrical mold to rotate by using a mechanical arm, pulling out the cylindrical mold in the middle of the circular ring mold after freezing, adding the uniform mixture into a gap in the middle after removing the cylindrical mold again, and freezing by using the ice template method to obtain a central radial carbon nanotube skeleton precursor; (3) And performing vacuum freeze drying treatment (the vacuum freeze drying time is 12-72 h, the vacuum freeze drying temperature is-80-20 ℃ and the vacuum freeze drying vacuum pressure is-60 Pa-10 Pa) on the frozen product to obtain the central radial carbon nanotube skeleton.
A third aspect of the present invention provides the use of a central radial carbon nanotube backbone as described above as a filler in the field of thermally conductive phase change composites.
The fourth aspect of the present invention provides a thermally conductive phase change composite material comprising a phase change polymer matrix and a central radial carbon nanotube backbone as described above; the phase change polymer matrix is one or more of polyethylene glycol, paraffin, stearic acid, eutectic alloy base polymer and silicon base polymer; and the volume percentage of the central radial carbon nanotube skeleton is 1-8 percent based on 100 percent of the total volume of the heat-conducting phase-change composite material.
In the present invention, the thermal conductivity of the thermal conductive phase change composite material is 0.4W/(m·k) to 5W/(m·k), for example, 0.4W/(m·k), 1.0W/(m·k), 1.5W/(m·k), 1.8W/(m·k), 2.0W/(m·k), 2.5W/(m·k), 3.3W/(m·k), 3.9W/(m·k), 4.2W/(m·k), 4.8W/(m·k), or 5W/(m·k), or the like.
In the technical scheme of the invention, the phase change latent heat of the heat conduction phase change composite material is 120J/g-270J/g, for example, 120J/g, 140J/g, 160J/g, 180J/g, 200J/g, 220J/g, 240J/g, 260J/g or 270J/g and the like.
In the technical scheme of the invention, the volume resistivity of the heat-conducting phase-change composite material is 5.0 multiplied by 10 -4 Ω·cm～9.0×10 -1 Omega cm, e.g. 5.0X10 -4 Ω·cm、8.3×10 -4 Ω·cm、9.7×10 -4 Ω·cm、2.3×10 -3 Ω·cm、5.9×10 -3 Ω·cm、8.6×10 -3 Ω·cm、2.5×10 -2 Ω·cm、6.1×10 -2 Ω·cm、8.4×10 -2 Ω·cm、5.0×10 -1 Omega cm or 9.0X10 -1 Omega cm, etc.
As the preferable technical scheme of the heat-conducting phase-change composite material, the preferable technical scheme provides a heat-conducting phase-change composite material which is formed by taking a central radial carbon nanotube skeleton as a filler and taking a phase-change polymer as a matrix. In the preferred technical scheme, the structural morphology of the filler frameworks is further controlled by controlling the formation of ice crystals in a solute suspension between the central radial carbon nanotube frameworks through an ice template method, so that a radial and lamellar porous structure with a longitudinal arrangement of the centers and outwards extended centers is formed.
Preferably, the volume percentage of the central radial carbon nanotube skeleton is 1% -8%, for example 1%, 2%, 3%, 4%, 5%, 6%, 7% or 8%, etc., based on 100% of the total volume of the thermally conductive phase change composite material.
In the technical scheme of the invention, the total volume of the central radial carbon nanotube skeleton and the phase-change polymer matrix is 100%.
A fifth aspect of the present invention provides a method of preparing a thermally conductive phase change composite material, the method comprising:
Heating the phase-change polymer in a beaker, and adding the phase-change polymer in the liquid phase into the central radial carbon nanotube skeleton when the phase-change polymer is changed from a solid phase to a liquid phase;
and (3) putting the die containing the phase-change polymer and the central radial carbon nanotube skeleton into a vacuum hot press, performing three-stage vacuum treatment, and performing hot press treatment to obtain the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and taking the phase-change polymer as a matrix.
Further, the heating temperature is 70℃to 150℃such as 70℃80℃90℃100℃110℃120℃130℃140℃150 ℃.
The three-stage vacuum treatment specifically comprises the following steps: the vacuum pressure of the first section is-20 Pa to-30 Pa, and the time is 0.5h to 1h; the vacuum pressure of the second section is-30 Pa to-40 Pa, and the time is 0.5h to 1h; the third section vacuum pressure is-40 Pa to-50 Pa, and the time is 0.5h to 1h. The vacuum pressure of the first section is-20 Pa to-30 Pa, and the time is 0.5h to 1h; for example, -20Pa, -22Pa, -24Pa, -26Pa, -28Pa, or-30 Pa, etc.; for example, 0.5h, 0.6h, 0.7h, 0.8h, 0.9h, 1h, etc. The vacuum pressure of the second section is-30 Pa to-40 Pa, and the time is 0.5h to 1h; for example, -30Pa, -32Pa, -34Pa, -36Pa, -38Pa, or-40 Pa, etc.; for example, 0.5h, 0.6h, 0.7h, 0.8h, 0.9h, 1h, etc. The third section vacuum pressure is-40 Pa to-50 Pa, and the time is 0.5h to 1h; for example, -40Pa, -42Pa, -44Pa, -46Pa, -48Pa, or-50 Pa, etc.; for example, 0.5h, 0.6h, 0.7h, 0.8h, 0.9h, 1h, etc.
The pressure of the hot pressing treatment is 50 Pa-500 Pa, such as 50Pa, 100Pa, 150Pa, 200Pa, 250Pa, 300Pa, 350Pa, 400Pa, 450Pa or 500Pa, etc. The temperature is 50 to 120 ℃, for example, 50 ℃, 57 ℃, 59 ℃, 62 ℃, 65 ℃, 70 ℃, 77 ℃, 82 ℃, 88 ℃, 95 ℃, 100 ℃, 110 ℃, 120 ℃, or the like. The time is 1h to 4h, for example, 1h, 1.7h, 2.8h, 3.5h, 4h, etc.
As a further preferable technical scheme of the preparation method of the heat-conducting phase-change composite material, the method comprises the following steps: placing the phase-change polymer into a beaker for heating (the heating temperature is 70-150 ℃), and adding the liquid-phase-change polymer into the central radial carbon nanotube skeleton when the phase-change polymer changes from a solid phase to a liquid phase; and (3) placing the die comprising the phase-change polymer and the central radial carbon nanotube skeleton into a vacuum hot press, performing three-section vacuum treatment (the first section vacuum pressure is-20 Pa to-30 Pa, the time is 0.5h to 1h, the second section vacuum pressure is-30 Pa to-40 Pa, the time is 0.5h to 1h, the third section vacuum pressure is-40 Pa to-50 Pa, the time is 0.5h to 1 h), and then performing hot pressing treatment (the hot pressing pressure is 50Pa to 500Pa, the hot pressing temperature is 50 ℃ to 120 ℃ and the hot pressing time is 1h to 4 h), so as to obtain the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and the phase-change polymer as a matrix.
Compared with the prior art, the invention has the following beneficial effects:
(1) The central radial carbon nanotube skeleton provided by the invention has radial and lamellar porous structures with longitudinally arranged centers and outwards extended centers. And a macroscopic heat conduction network is formed, excellent heat conduction performance is given to the composite material under the condition of low filler content, and the heat conduction coefficient of the composite material is improved to the greatest extent.
(2) The layered porous structure generated by the central radial carbon nanotube skeleton and the pore size which is uniformly distributed enable the composite material to show good heat conduction and heat storage performance and remarkable structural stability, and improve the packaging dimensional stability of the composite material in cold and hot circulation.
(3) The invention adopts the central radial carbon nanotube skeleton as the filler and adopts the polymer as the matrix to prepare the heat-conducting phase-change composite material, and the heat-conducting phase-change composite material not only has high heat conductivity coefficient and excellent heat storage performance, but also has good structural stability. The heat conduction coefficient of the heat conduction phase change composite material is 0.4W/(m.K) to 5W/(m.K), the phase change latent heat is 120J/g to 270J/g, and the volume resistivity is 5.0x10 -4 Ω·cm～2.0×10 -1 Omega cm, and no package leakage caused by cold and hot circulation at 25-60 ℃ for 1000 times.
Drawings
FIG. 1 is a schematic structural diagram of a heat-conducting phase-change composite material according to embodiment 1 of the present invention; wherein, the 1-heat conduction phase change composite material, the 11-center radial carbon nanotube framework and the 12-paraffin matrix;
FIG. 2 is a schematic view of an apparatus for an ice template method according to the present invention, wherein the diameter of a central radial carbon nanotube skeleton can be adjusted by changing the dimensions of a circular ring mold and a cylindrical mold, and a mechanical arm is used to keep the cylindrical mold rotating;
FIG. 3 is a SEM image of the surface morphology of the central radial carbon nanotube skeleton obtained in example 1 of the present invention;
FIG. 4 is a schematic diagram of a central radial carbon nanotube backbone heat conducting network according to the present invention;
fig. 5 is an electronic picture of the heat conductive phase change composite material obtained in comparative example 1 provided by the present invention.
Detailed Description
The first aspect of the present invention provides a central radial carbon nanotube skeleton, the skeleton comprising a central member, and a plurality of unit elements distributed along a circumferential direction of the central member and respectively connected with the central member; a gap is arranged between two adjacent single elements; the central piece is provided with a through hole structure penetrating through the middle piece in the axial direction; each of the unit pieces has a layered porous structure distributed along a circumferential direction of the center piece; the center piece and each of the unit pieces are made of hydroxyl-functionalized multi-walled carbon nanotubes. I.e. the skeleton is centrally radial.
The second aspect of the present invention provides a method for preparing a central radial carbon nanotube scaffold, the method comprising the steps of:
(1) Taking a hydroxyl functionalized multi-wall carbon nano tube, a binder and deionized water as raw materials to obtain a dispersion liquid, and performing ball milling treatment on the dispersion liquid to obtain a uniformly dispersed mixture;
(2) Preparing a circular ring mold, and arranging a gasket at the bottom of the circular ring mold, wherein the gasket is used for fixing a cylindrical mold arranged in the middle of the circular ring mold; adding the mixture into the circular ring mold, freezing by using an ice template method, keeping the cylindrical mold to rotate, and removing the cylindrical mold arranged in the middle of the circular ring mold after freezing; adding the mixture into a gap in the middle of the circular ring die after the cylindrical die is removed, and performing freezing treatment by using an ice template method to obtain a central radial carbon nanotube skeleton precursor;
(3) And carrying out vacuum freeze drying treatment on the precursor of the central radial carbon nanotube skeleton to obtain the central radial carbon nanotube skeleton.
A third aspect of the present invention provides the use of a central radial carbon nanotube backbone as described above as a filler in the field of thermally conductive phase change composites.
The fourth aspect of the present invention provides a thermally conductive phase change composite material comprising a phase change polymer matrix and a central radial carbon nanotube backbone as described above; the phase change polymer matrix is one or more of polyethylene glycol, paraffin, stearic acid, eutectic alloy base polymer and silicon base polymer; and the volume percentage of the central radial carbon nanotube skeleton is 1-8 percent based on 100 percent of the total volume of the heat-conducting phase-change composite material.
A fifth aspect of the present invention provides a method of preparing a thermally conductive phase change composite material, the method comprising:
heating the phase-change polymer in a beaker, and adding the phase-change polymer in the liquid phase into the central radial carbon nanotube skeleton when the phase-change polymer is changed from a solid phase to a liquid phase;
and (3) putting the die containing the phase-change polymer and the central radial carbon nanotube skeleton into a vacuum hot press, performing three-stage vacuum treatment, and performing hot press treatment to obtain the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and taking the phase-change polymer as a matrix.
The present invention will be described in further detail with reference to examples and comparative examples, but embodiments of the present invention are not limited thereto.
In order to make the technical problems, technical schemes and beneficial effects to be solved more clear, the invention is further described in detail below with reference to the embodiments and the accompanying drawings. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
Example 1
(1) Preparing a central radial carbon nanotube skeleton:
taking a hydroxyl-functionalized multi-wall carbon nano tube with the length of 20 mu m and the diameter of 5nm, and mixing the hydroxyl-functionalized multi-wall carbon nano tube, polyvinyl alcohol and deionized water according to the mass ratio of 1:5:20, preparing a dispersion liquid containing hydroxyl functionalized multi-wall carbon nano tubes, polyvinyl alcohol and deionized water, and performing ball milling treatment to obtain a uniformly dispersed mixture.
Adding the uniform mixture into a circular ring mold with the diameter of 30mm, adding a gasket at the bottom, fixing a middle cylindrical mold with the diameter of 5mm, freezing by using an ice template method, keeping the cylindrical mold to rotate by using a mechanical arm, pulling out the cylindrical mold in the middle of the circular ring mold after freezing, adding the uniform mixture into a gap in the middle of which the cylindrical mold is removed, and freezing by using the ice template method to obtain the central radial carbon nanotube skeleton precursor.
And performing vacuum freeze drying treatment on the obtained central radial carbon nanotube skeleton precursor, wherein the vacuum freeze drying time is 72h, the vacuum freeze drying temperature is-50 ℃, and the vacuum freeze drying vacuum pressure is-30 Pa, so as to obtain the central radial carbon nanotube skeleton. The diameter of the obtained central radial carbon nanotube skeleton is 30mm.
(2) Preparing a heat-conducting phase-change composite material by taking a central radial carbon nanotube framework as a filler:
heating paraffin in a beaker at 100deg.C until the paraffin is changed from solid phase to liquid phase, and adding liquid phase paraffin into the central radial carbon nanotube skeleton;
putting a die containing paraffin and a central radial carbon nanotube skeleton into a vacuum hot press, and performing three-section vacuum treatment, wherein the first section vacuum pressure is-25 Pa, and the time is 0.5h; the vacuum pressure of the second section is-35 Pa, and the time is 0.7h; and the third section of vacuum pressure is-45 Pa for 0.8h, then hot pressing treatment is carried out, the hot pressing pressure is 500Pa, the hot pressing temperature is 120 ℃, and the hot pressing time is 3h, so that the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and paraffin as a matrix is obtained.
The schematic structural diagram of the thermal conduction phase change composite material prepared by the embodiment is shown in fig. 1 (fig. a is a schematic three-dimensional structural diagram of the thermal conduction phase change composite material; fig. b is a schematic planar structural diagram of the thermal conduction phase change composite material under an angle), wherein 1 is the thermal conduction phase change composite material; 11 is a central radial carbon nanotube skeleton; 12 is paraffin wax as a matrix.
The central radial carbon nanotube skeleton 1 further controls the structural morphology of the hydroxyl functional multiwall carbon nanotube skeleton by controlling the formation of ice crystals in a solute suspension by an ice template method, and forms an effective three-dimensional heat conduction network, so that the high heat conduction coefficient of the phase-change composite material is realized, and the heat conduction coefficient is 1.7W/(m.K). The paraffin wax used in the technical scheme of the invention has higher phase change latent heat, and the phase change latent heat of the composite material is 230J/g. The hydroxyl functional multiwall carbon nano tube used in the technical proposal of the invention has lower conductivity, and the volume resistivity of the composite material is 7.3 multiplied by 10 -3 Omega cm. Meanwhile, the central radial carbon nanotube skeleton 1 forms a micro-network structure with rich pore structures, has good adsorption effect on paraffin substrates, and has no package leakage after cold and hot circulation for 1000 times at 20-60 ℃.
Fig. 2 is a schematic view of an apparatus for an ice pattern plate method used in example 1, in which the diameter of a central radial carbon nanotube skeleton can be adjusted by changing the dimensions of a circular ring mold and a cylindrical mold, and the cylindrical mold is kept to rotate by a robot arm.
FIG. 3 is a SEM image of the surface morphology of a 30mm diameter center radial carbon nanotube backbone obtained in example 1, from which it can be seen that a layered porous structure is formed between hydroxyl-functionalized multi-walled carbon nanotubes.
Fig. 4 is a schematic view of a heat conducting network of a central radial carbon nanotube skeleton in the heat conducting phase change composite material obtained in example 1, and it can be seen that the central radial carbon nanotube skeleton presents a radial layered porous arrangement with a central longitudinal arrangement and an outward center extension, so as to provide a perfect heat conducting path.
Example 2
(1) Preparing a central radial carbon nanotube skeleton:
taking a hydroxyl-functionalized multi-wall carbon nano tube with the length of 50 mu m and the diameter of 80nm, and mixing the hydroxyl-functionalized multi-wall carbon nano tube, polyoxyethylene and deionized water according to the mass ratio of 1:20:100, preparing a dispersion liquid containing hydroxyl functionalized multi-wall carbon nano tubes, polyoxyethylene and deionized water, and performing ball milling treatment to obtain a uniformly dispersed mixture.
Adding the uniform mixture into a circular ring mold with the diameter of 40mm, adding a gasket at the bottom, fixing a middle cylindrical mold with the diameter of 7mm, freezing by using an ice template method, keeping the cylindrical mold to rotate by using a mechanical arm, pulling out the cylindrical mold in the middle of the circular ring mold after freezing, adding the uniform mixture into a gap in the middle of which the cylindrical mold is removed, and freezing by using the ice template method to obtain the central radial carbon nanotube skeleton precursor.
And performing vacuum freeze drying treatment on the obtained central radial carbon nanotube skeleton precursor, wherein the vacuum freeze drying time is 48 hours, the vacuum freeze drying temperature is-30 ℃, and the vacuum freeze drying vacuum pressure is-50 Pa, so as to obtain the central radial carbon nanotube skeleton. The diameter of the obtained central radial carbon nanotube skeleton is 40mm.
(2) Preparing a heat-conducting phase-change composite material by taking a central radial carbon nanotube framework as a filler:
heating polyethylene glycol in a beaker at 110deg.C until the polyethylene glycol changes from solid phase to liquid phase, and adding liquid phase polyethylene glycol into the central radial carbon nanotube skeleton;
putting a die containing polyethylene glycol and a central radial carbon nanotube framework into a vacuum hot press, and performing three-section vacuum treatment, wherein the vacuum pressure of the first section is-20 Pa, and the time is 1h; the vacuum pressure of the second section is-30 Pa, and the time is 1h; and the third section of vacuum pressure is-40 Pa for 1h, then hot pressing treatment is carried out, the hot pressing pressure is 360Pa, the hot pressing temperature is 80 ℃, and the hot pressing time is 1h, so that the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and polyethylene glycol as a matrix is obtained.
The thermal conductive phase change composite material prepared by the embodiment and prepared by taking the central radial carbon nanotube skeleton as the filler is subjected to performance index test, wherein the thermal conductivity coefficient is 3.48W/m.K, the phase change latent heat is 180J/g, and the volume resistivity is 2.1 multiplied by 10 -2 Omega cm, and no leakage in cold and hot circulation at 20-60 deg.c for 1000 times.
Example 3
(1) Preparing a central radial carbon nanotube skeleton:
taking a hydroxyl-functionalized multi-wall carbon nano tube with the length of 1 mu m and the diameter of 8nm, and mixing the hydroxyl-functionalized multi-wall carbon nano tube, polyacrylamide and deionized water according to the mass ratio of 1:1: and 5, preparing a dispersion liquid containing the hydroxyl functionalized multiwall carbon nanotubes, polyacrylamide and deionized water, and performing ball milling treatment to obtain a uniformly dispersed mixture.
Adding the uniform mixture into a circular ring mold with the diameter of 10mm, adding a gasket at the bottom, fixing a middle cylindrical mold with the diameter of 2mm, freezing by using an ice template method, keeping the cylindrical mold to rotate by using a mechanical arm, pulling out the cylindrical mold in the middle of the circular ring mold after freezing, adding the uniform mixture into a gap in the middle of which the cylindrical mold is removed, and freezing by using the ice template method to obtain the central radial carbon nanotube skeleton precursor.
And performing vacuum freeze drying treatment on the obtained central radial carbon nanotube skeleton precursor, wherein the vacuum freeze drying time is 12h, the vacuum freeze drying temperature is-20 ℃, and the vacuum freeze drying vacuum pressure is-10 Pa, so as to obtain the central radial carbon nanotube skeleton. The diameter of the obtained central radial carbon nanotube skeleton is 10mm.
(2) Preparing a heat-conducting phase-change composite material by taking a central radial carbon nanotube framework as a filler:
heating stearic acid in a beaker at 150 deg.c to change stearic acid from solid phase to liquid phase, and adding the liquid phase stearic acid into the central radial carbon nanotube skeleton;
placing a die containing stearic acid and a central radial carbon nanotube skeleton into a vacuum hot press for three-section vacuum treatment, wherein the vacuum pressure of the first section is-23 Pa, and the time is 0.6h; the vacuum pressure of the second section is-31 Pa, and the time is 0.8h; and the third section of vacuum pressure is minus 47Pa for 0.7h, then hot pressing treatment is carried out, the hot pressing pressure is 50Pa, the hot pressing temperature is 50 ℃, and the hot pressing time is 4h, so that the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and taking paraffin as a matrix is obtained.
The thermal conductive phase change composite material prepared by the embodiment and prepared by taking the central radial carbon nanotube skeleton as the filler is subjected to performance index test, wherein the thermal conductivity coefficient is 3.98W/m.K, the phase change latent heat is 134J/g, and the volume resistivity is 2.9x10 -1 Omega cm, and no leakage in cold and hot circulation at 20-60 deg.c for 1000 times.
Example 4
(1) Preparing a central radial carbon nanotube skeleton:
taking a hydroxyl-functionalized multi-wall carbon nano tube with the length of 30 mu m and the diameter of 60nm, and mixing the hydroxyl-functionalized multi-wall carbon nano tube, polyvinyl alcohol and deionized water according to the mass ratio of 1:15:30, preparing a dispersion liquid containing hydroxyl functionalized multi-wall carbon nano tubes, polyvinyl alcohol and deionized water, and performing ball milling treatment to obtain a uniformly dispersed mixture.
Adding the uniform mixture into a circular ring mold with the diameter of 50mm, adding a gasket at the bottom, fixing a middle cylindrical mold with the diameter of 10mm, freezing by using an ice template method, keeping the cylindrical mold to rotate by using a mechanical arm, pulling out the cylindrical mold in the middle of the circular ring mold after freezing, adding the uniform mixture into a gap in the middle of which the cylindrical mold is removed, and freezing by using the ice template method to obtain the central radial carbon nanotube skeleton precursor.
And performing vacuum freeze drying treatment on the obtained central radial carbon nanotube skeleton precursor, wherein the vacuum freeze drying time is 48 hours, the vacuum freeze drying temperature is-80 ℃, and the vacuum freeze drying vacuum pressure is-60 Pa, so as to obtain the central radial carbon nanotube skeleton. The diameter of the obtained central radial carbon nanotube skeleton is 50mm.
(2) Preparing a heat-conducting phase-change composite material by taking a central radial carbon nanotube framework as a filler:
heating polyethylene glycol in a beaker at 70deg.C until the polyethylene glycol changes from solid phase to liquid phase, and adding liquid phase polyethylene glycol into the central radial carbon nanotube skeleton;
putting a die containing polyethylene glycol and a central radial carbon nanotube framework into a vacuum hot press, and performing three-section vacuum treatment, wherein the vacuum pressure of the first section is-22 Pa, and the time is 0.6h; the vacuum pressure of the second section is-37 Pa, and the time is 0.8h; and the third section of vacuum pressure is-45 Pa for 0.9h, then hot pressing treatment is carried out, the hot pressing pressure is 50Pa, the hot pressing temperature is 90 ℃, and the hot pressing time is 2.5h, so that the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and polyethylene glycol as a matrix is obtained.
The thermal conductive phase change composite material prepared by the embodiment and prepared by taking the central radial carbon nanotube skeleton as the filler is subjected to performance index test, wherein the thermal conductivity coefficient is 2.7W/m.K, the phase change latent heat is 219J/g, and the volume resistivity is 2.7X10 -4 Omega cm, and no leakage in cold and hot circulation at 20-60 deg.c for 1000 times.
Comparative example 1
(1) Preparing a central radial carbon nanotube skeleton:
taking a hydroxyl-functionalized multi-wall carbon nano tube with the length of 20 mu m and the diameter of 5nm, and mixing the hydroxyl-functionalized multi-wall carbon nano tube, polyvinyl alcohol and deionized water according to the mass ratio of 1:5:15, preparing a dispersion liquid containing hydroxyl functionalized multi-wall carbon nano tubes, polyvinyl alcohol and deionized water, and performing ball milling treatment to obtain a uniformly dispersed mixture.
Adding the uniform mixture into a circular ring mold with the diameter of 30mm, adding a gasket at the bottom, fixing a middle cylindrical mold with the diameter of 5mm, freezing by using an ice template method, keeping the cylindrical mold to rotate by using a mechanical arm, pulling out the cylindrical mold in the middle of the circular ring mold after freezing, adding the uniform mixture into a gap in the middle of which the cylindrical mold is removed, and freezing by using the ice template method to obtain the central radial carbon nanotube skeleton precursor.
And performing vacuum freeze drying treatment on the obtained central radial carbon nanotube skeleton precursor, wherein the vacuum freeze drying time is 72h, the vacuum freeze drying temperature is-50 ℃, and the vacuum freeze drying vacuum pressure is-30 Pa, so as to obtain the central radial carbon nanotube skeleton. The diameter of the obtained central radial carbon nanotube skeleton is 30mm.
(2) Preparing a heat-conducting phase-change composite material by taking a central radial carbon nanotube framework as a filler:
heating paraffin in a beaker at 100deg.C until the paraffin is changed from solid phase to liquid phase, and adding liquid phase paraffin into the central radial carbon nanotube skeleton;
putting a die containing paraffin and a central radial carbon nanotube skeleton into a vacuum hot press, and performing three-section vacuum treatment, wherein the vacuum pressure of the first section is-30 Pa, and the time is 1h; the vacuum pressure of the second section is-40 Pa, and the time is 1h; and the third section of vacuum pressure is-50 Pa for 1h, then hot pressing treatment is carried out, the hot pressing pressure is 500Pa, the hot pressing temperature is 120 ℃, and the hot pressing time is 3h, so that the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and paraffin as a matrix is obtained.
The thermal conductive phase change composite material prepared by the comparative example and prepared by taking the central radial carbon nanotube skeleton as a filler is subjected to performance index test, wherein the thermal conductivity coefficient is 2.24W/m.K, the phase change latent heat is 198J/g, and the volume resistivity is 9.6X10 -1 Omega cm, and no leakage in cold and hot circulation at 20-60 deg.c for 1000 times.
Fig. 5 is an electronic picture of the thermally conductive phase change composite material obtained in comparative example 1, and it can be seen from the figure that the central radial carbon nanotube skeleton is uniformly distributed in the paraffin matrix.
Comparative example 2
(1) Preparing a central radial carbon nanotube skeleton:
taking a hydroxyl-functionalized multi-wall carbon nano tube with the length of 50 mu m and the diameter of 80nm, and mixing the hydroxyl-functionalized multi-wall carbon nano tube, polyoxyethylene and deionized water according to the mass ratio of 1:20:50, preparing a dispersion liquid containing hydroxyl functionalized multi-wall carbon nano tubes, polyoxyethylene and deionized water, and performing ball milling treatment to obtain a uniformly dispersed mixture.
Adding the uniform mixture into a circular ring mold with the diameter of 20mm, adding a gasket at the bottom, fixing a middle cylindrical mold with the diameter of 5mm, freezing by using an ice template method, keeping the cylindrical mold to rotate by using a mechanical arm, pulling out the cylindrical mold in the middle of the circular ring mold after freezing, adding the uniform mixture into a gap in the middle of which the cylindrical mold is removed, and freezing by using the ice template method to obtain the central radial carbon nanotube skeleton precursor.
And performing vacuum freeze drying treatment on the obtained central radial carbon nanotube skeleton precursor, wherein the vacuum freeze drying time is 48 hours, the vacuum freeze drying temperature is-30 ℃, and the vacuum freeze drying vacuum pressure is-50 Pa, so as to obtain the central radial carbon nanotube skeleton. The diameter of the obtained central radial carbon nanotube skeleton is 20mm.
(2) Preparing a heat-conducting phase-change composite material by taking a central radial carbon nanotube framework as a filler:
heating paraffin in a beaker at 110 deg.c to change paraffin from solid phase to liquid phase, and adding liquid paraffin into the central radial carbon nanotube skeleton;
putting a die containing the paraffin wax and the central radial carbon nanotube skeleton into a vacuum hot press, and performing three-section vacuum treatment, wherein the first section vacuum pressure is-20 Pa, and the time is 1h; the vacuum pressure of the second section is-30 Pa, and the time is 1h; and the third section of vacuum pressure is-40 Pa for 1h, then hot pressing treatment is carried out, the hot pressing pressure is 360Pa, the hot pressing temperature is 80 ℃, and the hot pressing time is 1h, so that the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and paraffin as a matrix is obtained.
The thermal conductive phase change composite material prepared by the embodiment and prepared by taking the central radial carbon nanotube skeleton as the filler is subjected to performance index test, wherein the thermal conductivity coefficient is 4.12W/m.K, the phase change latent heat is 156J/g, and the volume resistivity is 7.6X10 -2 Omega cm, and no leakage in cold and hot circulation at 20-60 deg.c for 1000 times.
Comparative example 3
(1) Preparing a central radial carbon nanotube skeleton:
taking a hydroxyl-functionalized multi-wall carbon nano tube with the length of 1 mu m and the diameter of 8nm, and mixing the hydroxyl-functionalized multi-wall carbon nano tube, polyacrylamide and deionized water according to the mass ratio of 1:1: and 5, preparing a dispersion liquid containing the hydroxyl functionalized multiwall carbon nanotubes, polyacrylamide and deionized water, and performing ball milling treatment to obtain a uniformly dispersed mixture.
Adding the uniform mixture into a circular ring mold with the diameter of 40mm, adding a gasket at the bottom, fixing a middle cylindrical mold with the diameter of 5mm, freezing by using an ice template method, keeping the cylindrical mold to rotate by using a mechanical arm, pulling out the cylindrical mold in the middle of the circular ring mold after freezing, adding the uniform mixture into a gap in the middle of which the cylindrical mold is removed, and freezing by using the ice template method to obtain the central radial carbon nanotube skeleton precursor.
And performing vacuum freeze drying treatment on the obtained central radial carbon nanotube skeleton precursor, wherein the vacuum freeze drying time is 48 hours, the vacuum freeze drying temperature is-20 ℃, and the vacuum freeze drying vacuum pressure is-10 Pa, so as to obtain the central radial carbon nanotube skeleton. The diameter of the obtained central radial carbon nanotube skeleton is 40mm.
(2) Preparing a heat-conducting phase-change composite material by taking a central radial carbon nanotube framework as a filler:
heating stearic acid in a beaker at 150 deg.c to change stearic acid from solid phase to liquid phase, and adding the liquid phase stearic acid into the central radial carbon nanotube skeleton;
placing a die containing stearic acid and a central radial carbon nanotube skeleton into a vacuum hot press for three-section vacuum treatment, wherein the vacuum pressure of the first section is-23 Pa, and the time is 0.6h; the vacuum pressure of the second section is-31 Pa, and the time is 0.8h; and the third section of vacuum pressure is minus 47Pa for 0.7h, then hot pressing treatment is carried out, the hot pressing pressure is 50Pa, the hot pressing temperature is 50 ℃, and the hot pressing time is 4h, so that the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and taking paraffin as a matrix is obtained.
The thermal conductive phase change composite material prepared by the embodiment and prepared by taking the central radial carbon nanotube skeleton as the filler is subjected to performance index test, wherein the thermal conductivity coefficient is 4.09W/m.K, the phase change latent heat is 119J/g, and the volume resistivity is 5.6X10 -1 Omega cm, and no leakage in cold and hot circulation at 20-60 deg.c for 1000 times.
The embodiments described above are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the embodiments described above, and any other changes, modifications, substitutions, combinations, and simplifications that do not depart from the spirit and principles of the present invention should be made in the equivalent manner, and are included in the scope of the present invention.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims (10)

1. The central radial carbon nanotube framework is characterized by comprising a central piece and a plurality of single elements which are distributed along the circumferential direction of the central piece and are respectively connected with the central piece; a gap is arranged between two adjacent single elements;
the central piece is provided with a through hole structure penetrating through the middle piece in the axial direction;
each of the unit pieces has a layered porous structure distributed along a circumferential direction of the center piece;
the center piece and each of the unit pieces are made of hydroxyl-functionalized multi-walled carbon nanotubes.
2. The central radial carbon nanotube backbone of claim 1, wherein each of the unit pieces is in a sheet shape, a plane in which the unit piece in a sheet shape is located being parallel to an axial direction of the intermediate piece;
the diameter of the central radial carbon nanotube skeleton is 10-50 mm;
Wherein the length of the hydroxyl functional multiwall carbon nanotube is 1-50 μm, and the diameter is 5-80 nm.
3. The method for preparing a central radial carbon nanotube skeleton according to claim 1 or 2, comprising the steps of:
(1) Taking a hydroxyl functionalized multi-wall carbon nano tube, a binder and deionized water as raw materials to obtain a dispersion liquid, and performing ball milling treatment on the dispersion liquid to obtain a uniformly dispersed mixture;
(2) Preparing a circular ring mold, and arranging a gasket at the bottom of the circular ring mold, wherein the gasket is used for fixing a cylindrical mold arranged in the middle of the circular ring mold; adding the mixture into the circular ring mold, freezing by using an ice template method, keeping the cylindrical mold to rotate, and removing the cylindrical mold arranged in the middle of the circular ring mold after freezing; adding the mixture into a gap in the middle of the circular ring die after the cylindrical die is removed, and performing freezing treatment by using an ice template method to obtain a central radial carbon nanotube skeleton precursor;
(3) And carrying out vacuum freeze drying treatment on the precursor of the central radial carbon nanotube skeleton to obtain the central radial carbon nanotube skeleton.
4. The method for preparing a central radial carbon nanotube skeleton according to claim 3, wherein the mass ratio of the hydroxyl-functionalized multi-walled carbon nanotubes, the binder and deionized water in the step (1) is 1: (1-20): (5-100);
the binder is a water-soluble polymer;
preferably, the binder is one or more of polyacrylamide, polyacrylic acid, polyvinyl alcohol, polyoxyethylene, polyvinylpyrrolidone, cellulose derivative and starch-based adhesive.
5. The method for preparing a central radial carbon nanotube skeleton according to claim 3, wherein the circular ring mold in the step (2) is placed in liquid nitrogen;
the diameter of the circular ring mold is 10 mm-50 mm, and the diameter of the cylindrical mold is 2 mm-10 mm.
6. The method for preparing a central radial carbon nanotube skeleton according to claim 3, wherein the vacuum freeze-drying in the step (3) is performed at a temperature of-80 ℃ to-20 ℃ for 12h to 72h and at a vacuum pressure of-60 Pa to-10 Pa.
7. Use of the central radial carbon nanotube backbone of claim 1 or 2 as a filler in the field of thermally conductive phase change composites.
8. A thermally conductive phase change composite material comprising a phase change polymer matrix and a central radial carbon nanotube backbone according to claim 1 or 2;
the phase change polymer matrix is one or more of polyethylene glycol, paraffin, stearic acid, eutectic alloy base polymer and silicon base polymer;
and the volume percentage of the central radial carbon nanotube skeleton is 1-8 percent based on 100 percent of the total volume of the heat-conducting phase-change composite material.
9. The method of preparing a thermally conductive phase change composite material of claim 8, wherein the method comprises:
heating the phase-change polymer in a beaker, and adding the phase-change polymer in the liquid phase into the central radial carbon nanotube skeleton when the phase-change polymer is changed from a solid phase to a liquid phase;
and (3) putting the die containing the phase-change polymer and the central radial carbon nanotube skeleton into a vacuum hot press, performing three-stage vacuum treatment, and performing hot press treatment to obtain the heat-conducting phase-change composite material formed by taking the central radial carbon nanotube skeleton as a filler and taking the phase-change polymer as a matrix.
10. The method for preparing a thermally conductive phase change composite material as claimed in claim 9, wherein,
The heating temperature is 70-150 ℃;
the three-stage vacuum treatment specifically comprises the following steps: the vacuum pressure of the first section is-20 Pa to-30 Pa, and the time is 0.5h to 1h; the vacuum pressure of the second section is-30 Pa to-40 Pa, and the time is 0.5h to 1h; the third section vacuum pressure is-40 Pa to-50 Pa, and the time is 0.5h to 1h;
the pressure of the hot pressing treatment is 50 Pa-500 Pa, the temperature is 50 ℃ to 120 ℃ and the time is 1 h-4 h.
CN202310751615.7A 2023-06-25 2023-06-25 Center radial carbon nanotube framework, composite material, preparation method and application thereof Pending CN116970249A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117960123A (en) * 2024-04-02 2024-05-03 清华大学 Composite microsphere adsorbent of halloysite nanotube and cellulose derived carbon, and preparation method and application thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117960123A (en) * 2024-04-02 2024-05-03 清华大学 Composite microsphere adsorbent of halloysite nanotube and cellulose derived carbon, and preparation method and application thereof
CN117960123B (en) * 2024-04-02 2024-06-11 清华大学 Composite microsphere adsorbent of halloysite nanotube and cellulose derived carbon, and preparation method and application thereof

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