System and method for preparing two-dimensional carbon nanotube aggregate

Abstract

The invention provides a system and method for preparing a two-dimensional carbon nanotube aggregate, and the system comprises a raw material dispersing device which is used for dispersing a carbon nanotube material to obtain carbon nanotube dispersed powder; the aerosol generating device is communicated with the raw material dispersing device and is used for dispersing the carbon nanotube dispersed powder in air to prepare carbon nanotube aerosol; the film forming device comprises a carbon nano tube settling assembly, a screen, a traction assembly and a rolling assembly, the traction assembly is connected with the screen and drives the screen to move, the carbon nano tube settling assembly is communicated with the aerosol generating device, and the rolling assembly is connected with the carbon nano tube settling assembly. The carbon nano tube settling assembly is used for settling the carbon nano tube aerosol on the surface of the moving screen, and the two-dimensional carbon nano tube aggregate is formed after the rolling action of the rolling assembly; the preparation system provided by the invention is high in integration degree, and the two-dimensional carbon nanotube aggregate can be prepared by a low-cost and high-efficiency dry method.

Description

Technical Field

[0001] The present invention relates to the technical field of two-dimensional carbon nanotube aggregates and preparation technologies, and particularly relates to a system and method for preparing two-dimensional carbon nanotube aggregates. Background Art

[0002] Since the discovery of carbon nanotubes by Japanese electron microscopist Iijima in 1991, carbon nanotubes have attracted extensive attention due to their unique structure and excellent mechanical, electrical, thermal, and optical properties. However, in general, carbon nanotubes usually appear in granular or powdery forms, which causes great inconvenience for applications.

[0003] Two-dimensional carbon nanotube assemblies, including carbon nanotube papers and carbon nanotube films, are macroscopic material forms of carbon nanotubes. They have the characteristics of light weight, flexibility, electrical conductivity, thermal conductivity, and large specific surface area. At the same time, they combine the excellent functional characteristics of carbon nanotubes themselves and have important application prospects in the fields of electrode materials, shielding materials, environmental materials, filtering materials, and electronic materials.

[0004] However, the current preparation of two-dimensional carbon nanotube assemblies has problems such as high preparation costs and low preparation efficiency due to complex preparation processes, and urgent improvement is needed. Summary of the Invention

[0005] In view of the above problems existing in the prior art, the present invention provides a system and method for preparing two-dimensional carbon nanotube aggregates to achieve low-cost and high-efficiency dry preparation of two-dimensional carbon nanotube aggregates.

[0006] The specific content of the invention is as follows: In the first aspect, the present invention provides a system for preparing two-dimensional carbon nanotube aggregates, including: A raw material dispersion device for dispersing carbon nanotube materials to obtain carbon nanotube dispersed powders; An aerosol generation device connected to the raw material dispersion device for preparing carbon nanotube aerosols by the synergistic action of air flow and mechanical stirring on the carbon nanotube dispersed powders; A film-forming device including a carbon nanotube sedimentation component, a screen, a traction component, and a rolling component. The traction component is connected to the screen and drives the screen to move. The carbon nanotube sedimentation component is connected to the aerosol generation device. The carbon nanotube sedimentation component is used to sediment the carbon nanotube aerosols on the surface of the moving screen, and then form the two-dimensional carbon nanotube aggregates after the rolling action of the rolling component.

[0007] Optionally, the aerosol generation device includes a sealed tank, an air compressor, and a mechanical stirring component; The air compressor is connected to the sealed tank to introduce air flow into the sealed tank; the mechanical stirring assembly is arranged in the sealed tank, and the sealed tank is connected to the raw material dispersion device and the film forming device; The carbon nanotube dispersed powder entering the sealed tank forms the carbon nanotube aerosol under the synergistic action of the air flow and mechanical stirring.

[0008] Optionally, the carbon nanotube sedimentation assembly includes a diversion pipeline and a negative pressure box; One end of the diversion pipeline is closed and the other end is open. The closed end of the diversion pipeline is communicated with the aerosol generating device, and the open end is located above the screen; The negative pressure box is arranged below the screen. A part of the upper cover of the negative pressure box has a porous structure, and the porous structure corresponds to the open end in the vertical direction; The negative pressure environment provided by the negative pressure box sucks the carbon nanotube aerosol into the diversion pipeline and settles on the surface of the moving screen through the open end.

[0009] Optionally, the porous structure is composed of a quartz sand core or a stainless steel sintered plate; The porosity of the porous structure is 30% - 60%.

[0010] Optionally, the carbon nanotube sedimentation assembly further includes a vacuum pump, and the negative pressure box is connected to the vacuum pump so that the pressure in the negative pressure box is maintained at -0.01 to -1 Mpa.

[0011] Optionally, the screen is made of filter paper, nylon filter membrane, PTFE filter membrane or cellulose filter membrane; The aperture of the screen is 0.1 - 10 um.

[0012] Optionally, the traction assembly includes a first reel, a second reel and a conveyor belt. The screen is fixed in a roll on the first reel. One end of the conveyor belt is connected to the end of the screen, and the other end is fixed to the second reel. As the second reel rotates, it drives the screen to move horizontally.

[0013] Optionally, the traction assembly further includes a third reel, and the third reel is used to wind up the prepared two-dimensional carbon nanotube aggregates.

[0014] In a second aspect, the present invention provides a method for two-dimensional carbon nanotube aggregates, and the method is applicable to the system described in the first aspect above, including: Feeding the carbon nanotube material into the raw material dispersion device, and performing primary dispersion under a shearing action to obtain carbon nanotube dispersed powder; Feed the carbon nanotube dispersed powder into an aerosol generating device to disperse the carbon nanotube dispersed powder in a gas phase to form a carbon nanotube aerosol; The carbon nanotube aerosol is deposited on the surface of the moving screen through a carbon nanotube sedimentation component, and after being rolled by the rolling component, the two-dimensional carbon nanotube aggregate is formed.

[0015] Optionally, the carbon nanotube material is selected from multi-walled carbon nanotubes and / or few-walled carbon nanotubes, and the carbon nanotubes have a diameter of 1 nm - 100 nm and a length of 1 μm - 1 cm.

[0016] Optionally, the thickness of the two-dimensional carbon nanotube aggregate is 10 nm - 1 mm.

[0017] Compared with the prior art, the present invention has the following advantages: The system for preparing two-dimensional carbon nanotube aggregates provided by the present invention includes: a raw material dispersion device for dispersing carbon nanotube materials to obtain carbon nanotube dispersed powder; an aerosol generating device connected to the raw material dispersion device for dispersing the carbon nanotube dispersed powder in air to prepare a carbon nanotube aerosol; a film-forming device including a carbon nanotube sedimentation component, a screen, a traction component and a rolling component, the traction component connects the screen and drives the screen to move, the carbon nanotube sedimentation component is connected to the aerosol generating device, and the carbon nanotube sedimentation component is used to deposit the carbon nanotube aerosol on the surface of the moving screen, and after being rolled by the rolling component, the two-dimensional carbon nanotube aggregate is formed; the preparation system provided by the present invention has a high degree of integration and can realize low-cost and high-efficiency dry preparation of two-dimensional carbon nanotube aggregates.

[0018] When preparing two-dimensional carbon nanotube aggregates with the preparation system provided by the present invention, the use of other reagents or components other than carbon nanotube materials will not be involved. The prepared two-dimensional carbon nanotube aggregates only contain carbon and no other impurities, and are high-quality two-dimensional carbon nanotube aggregate materials.

[0019] When preparing two-dimensional carbon nanotube aggregates with the preparation system provided by the present invention, the thickness and size of the product can be freely adjusted by controlling the sedimentation range and the weight of the deposited carbon nanotubes to meet the diverse product selection. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1 Shows a schematic structural diagram of a preparation system for two-dimensional carbon nanotube aggregates provided by an embodiment of the present invention; Figure 2 Shows a scanning electron micrograph of two-dimensional carbon nanotube aggregates provided by an embodiment of the present invention; Figure 3 Shows a scanning electron micrograph of another two-dimensional carbon nanotube aggregate provided by an embodiment of the present invention. Detailed implementation manners

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way limits the present invention and its application or use. Based on the embodiments of the present invention, any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other existing technologies falls within the protection scope of the present invention. And all other embodiments obtained by those of ordinary skill in the art without creative labor also belong to the protection scope of the present invention.

[0023] For the specific experimental steps or conditions not specified in the embodiments, the operations or conditions of the conventional experimental steps described in the existing technologies in the field can be followed. The reagents and other instruments not specified for the manufacturer can be conventional reagent products obtained through commercial purchase. In addition, the accompanying drawings are only schematic diagrams of the embodiments of the present invention and are not necessarily drawn to scale. The same reference numerals in the drawings represent the same or similar parts, and thus their repeated description will be omitted. Some of the block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0024] For technologies, methods, and devices known to those of ordinary skill in the relevant fields, detailed discussions may not be made, but under appropriate circumstances, the said technologies, methods, and devices should be regarded as part of the description of the present invention.

[0025] In the description of the present invention, it should be understood that using words such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Without further statement, the above words have no special meanings, and thus cannot be construed as limiting the protection scope of the present invention.

[0026] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0027] Before elaborating on a preparation system for two-dimensional carbon nanotube aggregates provided by the present invention, it is necessary to make the following description of related technologies: Existing methods for preparing carbon nanotube papers / membranes are mainly divided into dry methods and wet methods. Dry methods mainly include the floating method (FCCVD) and the film drawing method, and wet methods mainly rely on wet filtration; among them, the floating method is direct deposition growth, and by adding a catalyst (ferrocene) and a carbon source (alcohols, esters, ethers), carbon nanotube papers / membranes can be continuously obtained at the other end of the reactor. By adjusting the overall growth temperature, the type and temperature of the carbon source, carbon nanotube papers / membranes with different thicknesses can be obtained; however, due to equipment and process reasons, the floating method cannot guarantee product consistency during large-scale production, and the cost is relatively high. Some catalyst particles will be mixed into the formed film and cannot be purified and removed, affecting product performance.

[0028] The film drawing method is based on growing carbon nanotube arrays with longer dimensions. By connecting the head and tail, carbon nanotubes with a length of meters can be drawn out and intertwined and overlapped to obtain a large-area carbon nanotube film; however, the film drawing method requires the use of highly oriented long carbon nanotube arrays, with a high cost and difficulty in large-scale production.

[0029] Wet filtration is to disperse carbon nanotubes in a solvent, add a dispersant and other auxiliary fibers such as pulp and polymer fibers, and then filter and dry them into papers / membranes; although wet filtration can produce carbon nanotube papers / membranes with a lower cost, in large-scale production, nanoscale carbon nanotubes make filtration difficult, and it also involves a large amount of water, solvents, additives, etc., which is not environmentally friendly. During the dispersion process, over-dispersion often causes carbon nanotube breakage, affecting product performance.

[0030] Due to the above-mentioned preparation methods having varying degrees of complexity in the preparation process, high preparation difficulty, and the influence of impurities on product purity, the present invention realizes the continuous preparation of two-dimensional carbon nanotube aggregates by dry methods through system development and process design. The specific implementation content is as follows: In the first aspect, the present invention provides a system for preparing two-dimensional carbon nanotube aggregates, Figure 1 showing a schematic structural diagram of the two-dimensional carbon nanotube aggregate preparation system provided by the present invention, as Figure 1 shown, including: The raw material dispersion device 1 is used to disperse the carbon nanotube material to obtain a carbon nanotube dispersed powder; the aerosol generating device 2 is connected to the raw material dispersion device and is used to prepare a carbon nanotube aerosol by the synergistic action of air flow and mechanical stirring on the carbon nanotube dispersed powder; the film forming device 3 includes a carbon nanotube sedimentation component 301, a screen 302, a traction component 303 and a rolling component 304. The traction component 303 is connected to the screen 302 and drives the screen 302 to move. The carbon nanotube sedimentation component 301 is connected to the aerosol generating device 2. The carbon nanotube sedimentation component 301 is used to sediment the carbon nanotube aerosol on the surface of the moving screen 302, and then, after being rolled by the rolling component 304, a two-dimensional carbon nanotube aggregate is formed.

[0031] In specific implementation, the present invention uses the raw material dispersion device 1 and the aerosol generating device 2 in combination. The carbon nanotube material is first primarily dispersed in the raw material dispersion device to fully unfold and evenly disperse the agglomerated carbon nanotubes in the material, obtaining a carbon nanotube dispersed powder. Furthermore, the aerosol generating device 2 then performs secondary dispersion on the carbon nanotube dispersed powder to obtain a carbon nanotube aerosol. Under the synergistic action of the raw material dispersion device 1 and the aerosol generating device 2, the carbon nanotube material is transformed from an unevenly dispersed stacked form to an aerosol form evenly dispersed in the gas phase, realizing dry dispersion of carbon nanotubes. This dispersion process does not involve the use of any chemical reagents, ensuring the purity of the carbon nanotubes.

[0032] In specific implementation, the carbon nanotube aerosol in the aerosol generating device 2 forms a two-dimensional carbon nanotube aggregate under the action of the film forming device 3. The structure of the film forming device 3 specifically includes a carbon nanotube sedimentation component 301, a screen 302, a traction component 303 and a rolling component 304; the traction component 303 is connected to the screen 302 and drives the screen 302 to move. The carbon nanotube sedimentation component 301 is connected to the aerosol generating device 2. The carbon nanotube sedimentation component 301 is used to... and then, after being rolled by the rolling component 304, a two-dimensional carbon nanotube aggregate is formed.

[0033] In specific implementation, after the carbon nanotube aerosol sediments on the surface of the moving screen 302, the rolling action of the rolling component 304 is also required to expel the interstitial air in the carbon nanotube aggregate, complete the cross-linking between carbon nanotubes, and realize densification. The rolled two-dimensional carbon nanotube aggregate already has certain mechanical properties and can be directly taken off the screen 302 to obtain the final product.

[0034] Compared with the existing film-drawing method for preparing two-dimensional carbon nanotube aggregates, the present invention does not require the carbon nanotube material to have a high degree of orientation, or requires the carbon nanotube material to be a long-sized array of carbon nanotubes, which effectively reduces the preparation cost; compared with the existing floatation method for preparing two-dimensional carbon nanotube aggregates, the present invention does not require the preparation of carbon nanotubes and two-dimensional carbon nanotube aggregates to be carried out simultaneously. The carbon nanotube material used in the present invention is a carbon nanotube material after impurities are removed. This reduces the preparation cost while the prepared two-dimensional carbon nanotube aggregates contain only carbon and no other impurities, and are high-quality two-dimensional carbon nanotube aggregate materials.

[0035] In some embodiments, the carbon nanotube material suitable for the present invention can be selected from multi-walled carbon nanotubes and / or few-walled carbon nanotubes. The carbon nanotube material has a diameter of 1 nm to 100 nm and a length of 1 um to 1 cm.

[0036] In specific implementation, the raw material dispersing device 1 can use mechanical shearing to perform primary dispersion of carbon nanotube materials. The mechanical shearing dispersion process includes: 5000-50000rpm, dispersion time 1-120min; it can also use air flow shearing to perform primary dispersion of carbon nanotube materials. The high-speed air flow shearing dispersion process includes air consumption 1-10m 3 / min, air pressure 0.1-0.8Mpa, dispersion time 1-120min.

[0037] In some embodiments, the aerosol generating device 2 includes a sealed can, an air compressor and a mechanical stirring assembly; the air compressor is connected to the sealed can to introduce airflow into the sealed can; the mechanical stirring assembly is arranged in the sealed can, and the airflow generated by the air compressor provides shear force to help the carbon nanotube dispersed powder entering the sealed can to disperse and prevent agglomeration; mechanical stirring can further promote dispersion and help form a uniform gas-solid mixture. Under the synergistic action of the airflow and mechanical stirring, the carbon nanotube dispersed powder entering the sealed can is uniformly dispersed in the gas phase to form a carbon nanotube aerosol.

[0038] See also Figure 1, the carbon nanotube sedimentation assembly 301 includes a diversion pipeline 3011 and a negative pressure box body 3012; one end of the diversion pipeline 3011 is closed and the other end is open. The closed end of the diversion pipeline 3011 is connected to the aerosol generating device 2. Specifically, the closed end of the diversion pipeline 3011 is connected to the sealed tank, and the open end is located above the screen 302; the negative pressure box body 3012 is arranged below the screen 302. A part of the upper cover of the negative pressure box body 3012 has a porous structure, and the porous structure corresponds to the open end of the diversion pipeline 3011 in the vertical direction; thus, the negative pressure environment in the negative pressure box body 3012 creates suction at the porous structure and acts on the open end of the diversion pipeline 3011 through the screen, sucking the carbon nanotube aerosol in the sealed tank into the diversion pipeline. The carbon nanotube aerosol settles on the surface of the moving screen through the open end.

[0039] The present invention specifically designs a carbon nanotube sedimentation assembly 301 that uses negative pressure adsorption to complete the sedimentation of carbon nanotube aerosol for the carbon nanotube aerosol obtained by dry dispersion; among them, the negative pressure box body 3012 provides continuous suction, and through the porous structure on the upper cover of the negative pressure box body 3012, the carbon nanotube aerosol formed in the sealed tank is sucked into the diversion pipeline 3011 and deposited on the screen 302 through the open end of the diversion pipeline 3011. The screen 302 moves as the traction assembly 303 moves. Thus, the carbon nanotube aerosol is spread out on the surface of the screen 302.

[0040] It should be noted that the composition material of the screen 302 used in the present invention can be filter paper, nylon filter membrane, PTFE filter membrane or cellulose filter membrane; the pore size of the screen is 0.1 - 10um; the screen 302 used in the present invention can meet the gas permeability.

[0041] It should be noted that the open end of the diversion pipeline 3011 is arranged opposite to the porous structure on the upper cover of the negative pressure box body 3012, and the area of the porous structure on the upper cover of the negative pressure box body 3012 is not greater than the area of the open end of the diversion pipeline 3011 to ensure that there is sufficient suction to suck the carbon nanotube aerosol from the sealed tank into the diversion pipeline 3011; in the carbon nanotube sedimentation assembly 301 provided by the present invention, by replacing the diversion pipeline 3011 to make the size of the open end of the diversion pipeline 3011 match the width of the screen 302, two-dimensional carbon nanotube aggregates of various sizes can be prepared.

[0042] In some embodiments, the porous structure is composed of a quartz sand core or a stainless steel sintered plate; the porosity of the porous structure is 30% - 60% to ensure the air permeability.

[0043] In some embodiments, the carbon nanotube sedimentation assembly 301 further includes a vacuum pump, and the negative pressure box body 3012 is connected to the vacuum pump to maintain the pressure in the negative pressure box body 3012 at -0.01 to -1 Mpa.

[0044] See Figure 1 Figure 1 , the traction assembly 303 includes a first reel 3031, a second reel 3032 and a conveyor belt 3033. The screen 302 is fixed in a roll on the first reel 3031. One end of the conveyor belt 3033 is connected to the end of the screen 302, and the other end is fixed to the second reel 3032. With the rotation of the second reel 3032, the screen 302 is driven to move horizontally. Cooperating with the traction assembly 303 provided by the present invention, continuous roll-to-roll preparation of two-dimensional carbon nanotube aggregates can be realized.

[0045] See Figure 1 Figure 1 , the traction assembly 303 further includes a third reel 3034, and the third reel 3034 is used for winding the prepared two-dimensional carbon nanotube aggregates. Since the two-dimensional carbon nanotube aggregates after roll pressing already have certain mechanical properties, the separation of the two-dimensional carbon nanotube aggregates from the screen 302 can be directly carried out. By setting the third reel 3034 in the present invention, the two-dimensional carbon nanotube aggregates after roll pressing can be wound, and the final product can be collected on the third reel 3034, and the screen 302 can be wound on the second reel 3032 to realize the separation of the screen 302 from the two-dimensional carbon nanotube aggregates.

[0046] It should be noted that the roll pressing assembly 304 provided by the present invention uses hot roll pressing to promote cross-linking between carbon nanotubes, and the working temperature can be controlled at 80 - 110 °C.

[0047] The preparation system provided by the present invention prepares two-dimensional carbon nanotube aggregates in a dry dispersion manner. The preparation process does not involve the use of any reagents, and by adjusting the sedimentation range of carbon nanotube aerosol and the weight of sedimented carbon nanotubes, two-dimensional carbon nanotube aggregates with a thickness of 10 nm - 1 mm can be obtained, meeting the diverse product selection.

[0048] In a second aspect, the present invention provides a method for two-dimensional carbon nanotube aggregates, which is applicable to the system described in the first aspect above, and includes: Feeding the carbon nanotube material into the raw material dispersion device, and performing primary dispersion under a shearing action to obtain carbon nanotube dispersed powder; Feeding the carbon nanotube dispersed powder into the aerosol generating device to disperse the carbon nanotube dispersed powder in the gas phase to form a carbon nanotube aerosol; The carbon nanotube aerosol is sedimented on the surface of the moving screen through the carbon nanotube sedimentation assembly, and then forms the two-dimensional carbon nanotube aggregates after being roll-pressed by the roll pressing assembly.

[0049] It should be noted that the raw material dispersion device 1 can perform primary dispersion of the carbon nanotube material by means of mechanical shearing. The process of mechanical shearing dispersion includes: 5000 - 50000 rpm, and the dispersion time is 1 - 120 min; it can also perform primary dispersion of the carbon nanotube material by means of high-speed air flow shearing. The process of high-speed air flow shearing dispersion includes an air consumption of 1 - 10 m 3 / min, an air pressure of 0.1 - 0.8 Mpa, and a dispersion time of 1 - 120 min.

[0050] During the travel process of the carbon nanotube aerosol, the air compressor and the sealed tank that make up the aerosol generating device are connected to each other, and the air compressor introduces air flow into the sealed tank; the mechanical stirring component in the sealed tank and the air flow generated by the air compressor help to shear and disperse the carbon nanotube dispersed powder entering the sealed tank to prevent agglomeration; mechanical stirring can further promote dispersion and help form a uniform gas-solid mixture. Under the synergistic action of the air flow and mechanical stirring, the carbon nanotube dispersed powder entering the sealed tank is evenly dispersed in the gas phase and forms a carbon nanotube aerosol.

[0051] Since the preparation method adopts all the technical solutions of the system described in the first aspect above, it at least has all the beneficial effects brought by the technical solutions of the first aspect above, and will not be repeated here.

[0052] To make those skilled in the art understand the present invention more clearly, the following embodiments are now used to describe in detail a system for preparing two-dimensional carbon nanotube aggregates according to the present invention.

[0053] Example 1 Refer to Figure 1 In the shown system, 10 g of multi-walled carbon nanotube material is placed in the raw material dispersion device 1 to form carbon nanotube dispersed powder by mechanical shearing. Among them, the rotation speed of mechanical shearing is 32000 rpm, and the dispersion time is 30 min.

[0054] The carbon nanotube dispersed powder enters the sealed tank of the aerosol generating device 2. The air compressor connected to the aerosol generating device 2 is turned on, and the mechanical stirring component in the aerosol generating device 2 is started. Under the synergistic action of the air flow (0.5 L / min) and mechanical stirring (rotation speed 20000 rpm), the carbon nanotube dispersed powder entering the sealed tank is evenly dispersed in the gas phase and forms a carbon nanotube aerosol.

[0055] Turn on the vacuum pump connected to the negative pressure box 3012 to keep the pressure of the negative pressure box 3012 at -1 Mpa. Start the traction assembly 303. The negative pressure box 3012 provides continuous suction. Through the porous structure on the upper cover of the negative pressure box 3012, the carbon nanotube aerosol formed in the sealed tank is sucked into the diversion pipeline 3011 and deposited on the screen 302 through the open end of the diversion pipeline 3011. The screen 302 moves horizontally with the traction assembly 303 at a moving speed of 5 cm / min. Specifically, the rotation of the first reel 3031 and the second reel 3032 drives the conveyor belt 3033 and the screen 302 to move horizontally to spread the carbon nanotube aerosol on the surface of the screen 302.

[0056] After the film material formed on the surface of the screen 302 is roll-pressed by the roll-pressing assembly 304, the temperature of the roll-pressing assembly 304 is 100 °C. The two-dimensional carbon nanotube aggregates formed after the roll-pressing have certain mechanical properties. Fix the end of the two-dimensional carbon nanotube aggregates on the third reel 3034, and then the roll-pressed two-dimensional carbon nanotube aggregates can be wound up. The final product is collected on the third reel 3034, and the screen 302 is wound up on the second reel 3032 to separate the screen 302 from the two-dimensional carbon nanotube aggregates. The scanning electron micrograph of the prepared two-dimensional carbon nanotube aggregates is shown in Figure 2 ; The thickness of the two-dimensional carbon nanotube aggregates is 38 um.

[0057] It should be noted that in the present invention, according to actual needs, the diversion pipeline 3011 and the screen 302 with appropriate sizes can be selected to prepare two-dimensional carbon nanotube aggregates of various sizes; the present invention can also obtain two-dimensional carbon nanotube aggregates with adjustable thickness by controlling the amount of carbon nanotube materials and regulating the moving speed of the screen 302 (1 - 5 cm / min) to achieve the production of diverse products.

[0058] Example 2 Refer to Figure 1 In the shown system, 17.33 g of multi-walled carbon nanotube materials are placed in the raw material dispersion device 1 to form carbon nanotube dispersed powder by high-speed gas shear. Among them, the air consumption of the high-speed gas shear is 10 m 3 / min, the air pressure is 0.8 Mpa, and the dispersion time is 50 min.

[0059] The carbon nanotube dispersed powder enters the sealed tank of the aerosol generating device 2. Turn on the air compressor connected to the aerosol generating device 2 and start the mechanical stirring assembly in the aerosol generating device 2. The carbon nanotube dispersed powder entering the sealed tank is uniformly dispersed in the gas phase under the combined action of the gas flow (0.6 L / min) and mechanical stirring (22000 rpm) to form carbon nanotube aerosol.

[0060] Turn on the vacuum pump connected to the negative pressure box body 3012, so that the pressure of the negative pressure box body 3012 is maintained at -1 Mpa. Start the traction assembly 303. The negative pressure box body 3012 provides continuous suction. Through the porous structure on the upper cover of the negative pressure box body 3012, the carbon nanotube aerosol formed in the sealed tank is sucked into the diversion pipeline 3011 and deposited on the screen 302 through the open end of the diversion pipeline 3011. The screen 302 moves horizontally at a moving speed of 5 cm / min along with the traction assembly 303. Specifically, the rotation of the first scroll 3031 and the second scroll 3032 drives the conveyor belt 3033 and the screen 302 to move horizontally, so as to spread the carbon nanotube aerosol on the surface of the screen 302.

[0061] After the film material formed on the surface of the screen 302 is roll-pressed by the roll-pressing assembly 304, the temperature of the roll-pressing assembly 304 is 100 °C. The two-dimensional carbon nanotube aggregate formed after the roll-pressing has certain mechanical properties. Fix the end of the two-dimensional carbon nanotube aggregate on the third scroll 3034, and then the roll-pressed two-dimensional carbon nanotube aggregate can be wound up. The final product is collected on the third scroll 3034, and the screen 302 is wound up on the second scroll 3032 to realize the separation of the screen 302 from the two-dimensional carbon nanotube aggregate. The scanning electron micrograph of the prepared two-dimensional carbon nanotube aggregate is shown in Figure 3 ; The thickness of the two-dimensional carbon nanotube aggregate is 47 μm.

[0062] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

[0063] For the method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the present invention is not limited by the described action sequence, because according to the present invention, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and components involved are not necessarily essential to the present invention.

[0064] The above has introduced in detail a system and method for preparing two-dimensional carbon nanotube aggregates. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A system for preparing two-dimensional carbon nanotube aggregates, characterized in that, Comprising: A raw material dispersion device for dispersing a carbon nanotube material to obtain a carbon nanotube dispersed powder; An aerosol generating device communicated with the raw material dispersion device for preparing a carbon nanotube aerosol under the synergistic action of air flow and mechanical stirring of the carbon nanotube dispersed powder; A film forming device including a carbon nanotube sedimentation component, a screen, a traction component and a rolling component, the traction component connecting the screen and driving the screen to move, the carbon nanotube sedimentation component being communicated with the aerosol generating device, the carbon nanotube sedimentation component being used for sedimenting the carbon nanotube aerosol on the surface of the moving screen, and then forming the two-dimensional carbon nanotube aggregate after the rolling action of the rolling component; 2. The system for preparing two-dimensional carbon nanotube aggregates according to claim 1, characterized in that, The aerosol generating device includes a sealed tank, an air compressor and a mechanical stirring component; The air compressor is connected to the sealed tank to introduce air flow into the sealed tank; the mechanical stirring component is arranged in the sealed tank, and the sealed tank is connected to the raw material dispersion device and the film forming device; The carbon nanotube dispersed powder entering the sealed tank forms the carbon nanotube aerosol under the synergistic action of the air flow and mechanical stirring.

3. The system for preparing two-dimensional carbon nanotube aggregates according to claim 1, wherein The carbon nanotube sedimentation component includes a diversion pipeline and a negative pressure box body; One end of the diversion pipeline is closed and the other end is open. The closed end of the diversion pipeline is communicated with the aerosol generating device, and the open end is located above the screen; The negative pressure box body is arranged below the screen, and a part of the upper cover of the negative pressure box body has a porous structure, and the porous structure corresponds to the open end in the vertical direction; The negative pressure environment provided by the negative pressure box body sucks the carbon nanotube aerosol into the diversion pipeline and settles on the surface of the moving screen through the open end.

4. The system for preparing the two-dimensional carbon nanotube aggregates according to claim 3, wherein, The porous structure is composed of a quartz sand core or a stainless steel sintered plate; The porosity of the porous structure is 30% - 60%.

5. The system for preparing the two-dimensional carbon nanotube aggregates according to claim 3, wherein The carbon nanotube sedimentation component further includes a vacuum pump, and the negative pressure box body is connected to the vacuum pump to maintain the pressure of the negative pressure box body at -0.01 to -1 Mpa.

6. The system for preparing the two-dimensional carbon nanotube aggregates according to claim 1, wherein, The composition material of the screen is filter paper, nylon filter membrane, PTFE filter membrane or cellulose filter membrane; The aperture of the screen is 0.1 - 10 um.

7. The system for preparing the two-dimensional carbon nanotube aggregates according to claim 1, wherein The traction component includes a first reel, a second reel and a conveyor belt. The screen is fixed in a roll on the first reel. One end of the conveyor belt is connected to the end of the screen, and the other end is fixed to the second reel and rotates with the second reel to drive the screen to move horizontally.

8. The system for preparing two-dimensional carbon nanotube aggregates according to claim 1, characterized in that, The traction component further includes a third reel for winding the prepared two-dimensional carbon nanotube aggregate.

9. A method for preparing two-dimensional carbon nanotube aggregates, characterized in that, The method is applicable to the system according to any one of claims 1 - 8 above, and the method includes: Feeding the carbon nanotube material into the raw material dispersion device and performing primary dispersion under mechanical shearing action to obtain a carbon nanotube dispersed powder; Feeding the carbon nanotube dispersed powder into the aerosol generating device to disperse the carbon nanotube dispersed powder in the gas phase to form a carbon nanotube aerosol; The carbon nanotube aerosol is deposited on the surface of the moving screen through the carbon nanotube sedimentation component, and then forms the two-dimensional carbon nanotube aggregate after being roll-pressed by the roll-pressing component.

10. The method according to claim 8, wherein The carbon nanotube material is selected from multi-walled carbon nanotubes and / or few-walled carbon nanotubes, and the diameter of the carbon nanotubes is 1 nm - 100 nm, and the length is 1 μm - 1 cm; The thickness of the two-dimensional carbon nanotube aggregate is 10 nm - 1 mm.

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