Continuous preparation system, method and application of narrow carbon nanotube band

Abstract

The invention provides a continuous preparation system and method of a carbon nanotube narrow band and application. The method comprises the following steps: preparing carbon nanotube aerogel by adopting a floating catalytic chemical vapor deposition method; an ultrasonic atomization system is used for spraying an organic solvent, and carbon nano tube narrow bands are formed after the carbon nano tube aerogel is shrunk and compacted; stacking the first group of carbon nanotube narrow bands above a roller diaphragm, rolling by an open mill, and winding and collecting by a second group of rollers to form a single-layer carbon nanotube narrow band roll; stacking a second group of carbon nano tube narrow bands above the single-layer carbon nano tube narrow band roll, rolling by the open mill, and winding and collecting by the first group of rollers to form two layers of carbon nano tube narrow band rolls; and repeating the operation to realize the continuous preparation of the narrow-band coils of the carbon nanotubes with different thicknesses. According to the method, the preparation process of the carbon nanotube film is optimized, the uniformity of the prepared film is improved, the large-area and high-quality carbon nanotube film capable of being continuously collected is prepared, the large-scale application requirement is met, and wide deployment and application of carbon nanotubes in many fields are promoted and accelerated.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon nanotubes, and in particular to a continuous preparation system, method and application of carbon nanotube narrow strips. Background Art

[0002] Carbon nanotubes, as a one-dimensional nanostructured material, are composed of perfect carbon hexagons that are seamlessly connected, and have the characteristics of high strength and ultra-light weight.

[0003] The unique graphite layer structure of carbon nanotubes not only gives carbon nanotube materials extraordinary mechanical properties, but also makes carbon nanotube materials show excellent electrical properties. These excellent performance characteristics make carbon nanotube materials continue to attract widespread attention from the scientific community at home and abroad. Compared with carbon fiber, the production process of carbon nanotubes is simpler and energy-saving, and has the advantages of non-toxicity and low pollution. Therefore, carbon nanotubes are regarded as having extremely broad development potential and application prospects.

[0004] Although carbon nanotubes have excellent performance and wide applicability, the carbon nanotube materials currently available on the market are mostly in the form of dispersed particles or powders, which adds a lot of difficulties to the practical application of carbon nanotubes. As a key form of carbon nanotube applications, carbon nanotube films have been deeply studied and applied in many fields such as field emission sources, optoelectronic and biosensors, transparent conductive films, heating elements, battery electrodes, absorbing materials, water purification technology and luminescent materials.

[0005] However, the preparation technology of carbon nanotube films, the cornerstone supporting the above applications, still faces many difficulties and challenges. Although significant progress has been made in the research field of preparing carbon nanotube films by floating catalytic chemical vapor deposition, and meter-scale film preparation has been achieved, the uniformity of the prepared films still cannot meet the requirements of some users, and the preparation area is still difficult to meet the actual needs of large-scale applications. Summary of the invention

[0006] In view of this, the purpose of the present invention is to propose a continuous preparation system, method and application of carbon nanotube narrow strips, further optimize the carbon nanotube film preparation process, break through the challenge of continuous large-scale preparation of carbon nanotube films, achieve efficient and stable production, and be able to prepare large-area, high-quality carbon nanotube films that can be continuously collected to meet the actual needs of large-scale applications, and promote the acceleration of the widespread deployment and application of carbon nanotubes in many fields.

[0007] The present invention provides a continuous preparation system for carbon nanotube narrow bands, comprising two groups of preparation subsystems, each group of preparation subsystems comprising: a tubular furnace, an ultrasonic atomization system, and a roller; the ultrasonic atomization system is arranged directly above the outlet of the tubular furnace; the roller is arranged below the outlet of the tubular furnace, and a polypropylene diaphragm is arranged in the roller; the outlet of the tubular furnace and the roller are connected by a conveyor belt;

[0008] An open mill is arranged at the center position between the two groups of preparation subsystems. A rubber roller for rolling the film is installed in the open mill. The open mill is connected to the roller through a conveyor belt.

[0009] The present invention also provides a method for continuously preparing a carbon nanotube narrow ribbon, which is applied to the continuous preparation system for the carbon nanotube narrow ribbon as described above, and comprises the following steps:

[0010] S1. Preparing carbon nanotube aerogel by floating catalytic chemical vapor deposition method, comprising: ultrasonically mixing carbon source, catalyst and co-catalyst additives, and then gasifying them by ultrasonic atomization and heating tube, and uniformly injecting them into the furnace of a tube furnace, forming carbon nanotube gas and elastic smoke in the high temperature area of ​​the furnace, and the carbon nanotube gas and elastic smoke flow along the furnace with the inert hot air flow;

[0011] When the carbon nanotube gas and elastic smoke reach the low-temperature area of ​​the furnace, the elastic smoke adheres to the inner wall of the reactor to form carbon nanotube aerogel and is continuously drawn out from the furnace outlet;

[0012] S2, using an ultrasonic atomization system to spray an organic solvent directly above the carbon nanotube aerogel extracted from the furnace outlet, wherein the organic solvent completely wets the carbon nanotube aerogel, causing the carbon nanotube aerogel to shrink and compact to form a carbon nanotube narrow ribbon;

[0013] According to actual needs, the width of the carbon nanotube narrow band can be adjusted by the flow rate of the atomization injection pump of the ultrasonic atomization system.

[0014] S3, stacking the carbon nanotube narrow ribbons of the first preparation subsystem on top of the polypropylene diaphragm of the drum through a conveyor belt, rolling the carbon nanotube narrow ribbons through a rubber roller in an open mill to make the carbon nanotube narrow ribbons adhere to the surface of the polypropylene diaphragm, and winding the diaphragm with a single-layer carbon nanotube narrow ribbon on the surface through the drum of the second preparation subsystem to form a single-layer carbon nanotube narrow ribbon roll;

[0015] In a preferred embodiment, the winding length can reach kilometers and can be adjusted arbitrarily.

[0016] S4, stacking the carbon nanotube narrow ribbon of the second preparation subsystem on top of the single-layer carbon nanotube narrow ribbon roll through a conveyor belt, rolling the carbon nanotube narrow ribbon with a rubber roller in an open mill to make the carbon nanotube narrow ribbon adhere to the surface of the single-layer carbon nanotube narrow ribbon roll, and collecting the diaphragm containing two layers of carbon nanotube narrow ribbons by winding the roller of the first preparation subsystem to form a two-layer carbon nanotube narrow ribbon roll;

[0017] Specifically, the winding length of the two-layer carbon nanotube narrow ribbon roll in step S4 is the same as the winding length of the single-layer carbon nanotube narrow ribbon roll in step S3; S5. Repeat the operations of step S3 and step S4 to achieve continuous preparation of carbon nanotube narrow ribbon rolls of different thicknesses, and vacuum dry them in a vacuum drying oven at 79-81° C. to obtain a multilayer carbon nanotube narrow ribbon roll.

[0018] The uniformity of the carbon nanotube film prepared by rolling on an open mill and winding on a drum is greatly improved.

[0019] Furthermore, the carbon source in step S1 is one or more of acetone, anhydrous ethanol or toluene, the catalyst is ferrocene, the co-catalyst additive is sulfide, the ultrasonic time of ultrasonic mixing is 5-30min, the flow rate of the atomization injection pump for ultrasonic atomization is 30-80ml / h, the heating tube temperature of the heating tube gasification is 180-250°C, and the temperature of the high temperature zone is 1100-1500°C.

[0020] Furthermore, the organic solvent in step S2 is one or more of ethanol, acetone, dimethylformamide, dimethyl sulfoxide or N-methylpyrrolidone, the flow rate of the atomization injection pump of the ultrasonic atomization system is 0.5-5L / h, and the width of the carbon nanotube narrow band is 10-60mm.

[0021] Furthermore, in the step S3, the rolling speeds of the roller, the mixing mill and the conveyor belt of the first group of preparation subsystems are kept consistent, all of which are 15-150 r / min.

[0022] Furthermore, in the step S4, the rolling speeds of the roller, the mixing mill and the conveyor belt of the second group of preparation subsystems are kept consistent, all of which are 15-150 r / min, and the rotation direction of the roller and the conveying direction of the conveyor belt are opposite to those of the first group of preparation subsystems.

[0023] Applications of the carbon nanotube narrow strips prepared by the continuous preparation system of the carbon nanotube narrow strips and the continuous preparation method of the carbon nanotube narrow strips as described above include: application in electric heating, application in wireless signal shielding, and application in battery current collectors.

[0024] Compared with the prior art, the present invention has the following beneficial effects: The continuous preparation system, method and application of carbon nanotube narrow strips provided by the present invention break through the challenge of continuous large-scale preparation of carbon nanotube films by further optimizing the carbon nanotube film preparation process, improve the uniformity of the prepared carbon nanotube films, achieve efficient and stable production, and can prepare large-area, high-quality carbon nanotube films that can be continuously collected, meet the actual needs of large-scale applications, and effectively promote and accelerate the widespread deployment and application of carbon nanotubes in many fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the following detailed description of the preferred embodiment.The drawings are only for the purpose of illustrating the preferred embodiments and are not to be construed as limiting the invention.

[0026] In the attached picture: Figure 1 is a schematic diagram of the carbon nanotube aerogel according to an embodiment of the present invention shrinking and densifying after being wetted with an organic solvent; Figure 2 is a schematic diagram of a process of forming a carbon nanotube narrow ribbon roll A according to an embodiment of the present invention;

[0027] Figure 3 It is a schematic diagram of the formation process of the carbon nanotube narrow ribbon roll B according to an embodiment of the present invention.

[0028] The symbols in the accompanying drawings are:

[0029] 1. Carbon nanotube aerogel 1, 2. Carbon nanotube aerogel 2, 3. Ultrasonic atomization system 1, 4. Ultrasonic atomization system 2, 5. Carbon nanotube narrow belt 1, 6. Carbon nanotube narrow belt 2, 7. Roller 1, 8. Conveyor belt, 9. Mixing mill, 10. Roller 2. DETAILED DESCRIPTION

[0030] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and products consistent with some aspects of the present disclosure as detailed in the appended claims.

[0031] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. The singular forms of "a", "said" and "the" used in this disclosure and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0032] It should be understood that although the terms first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0033] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. The embodiments of the present invention include but are not limited to the following embodiments. Example 1

[0034] (1) Continuous carbon nanotube aerogel 1 and carbon nanotube aerogel 2 were prepared by floating catalytic chemical vapor deposition.

[0035] (2) If Figure 1 As shown, anhydrous ethanol is sprayed directly above the carbon nanotube aerogel 1 and the carbon nanotube aerogel 2 using ultrasonic atomization system 1 3 and ultrasonic atomization system 2 4, and the flow rate of the atomization injection pump is 1.3 L / h, so that the anhydrous ethanol completely wets the carbon nanotube aerogel 1 and the carbon nanotube aerogel 2, and after shrinking and densifying, a carbon nanotube narrow ribbon 1 5 and a carbon nanotube narrow ribbon 2 6 are formed.

[0036] (3) If Figure 2 As shown, the carbon nanotube narrow ribbon 1 5 is stacked on the polypropylene (PP) diaphragm of the roller 1 7 through the conveyor belt 8, rolled by the open mill 9, and continuously wound and collected by the roller 2 10 to form a kilometer-level single-layer carbon nanotube narrow ribbon roll A. The rolling speed of the roller, the open mill and the conveyor belt is kept consistent at 30r / min.

[0037] (4) If Figure 3 As shown, the carbon nanotube narrow ribbon 2 6 is stacked on top of the carbon nanotube narrow ribbon roll A through the conveyor belt 8, rolled by the open mill 9 and continuously wound and collected by the roller 1 7 to form a two-layer carbon nanotube narrow ribbon roll B of 100 meters. The rolling speed of the roller, the open mill and the conveyor belt is kept consistent at 30 r / min, and the rotation direction is opposite to the rotation direction of step (3).

[0038] (5) Repeat steps (3) and (4) for 40 times to obtain a multilayer carbon nanotube narrow ribbon roll with 80 layers stacked, and vacuum dry it in a vacuum drying oven at 80 °C for 2 h.

[0039] The length of the multi-layer carbon nanotube narrow ribbon roll obtained in Example 1 is about 1024m, the width is 48mm, the surface is flat and wrinkle-free and can be folded arbitrarily, the thickness is uniform, and the thickness deviation at different positions is within the range of ±8μm. Example 2

[0040] The difference between Example 2 and Example 1 is that the flow rate of the atomizing injection pump is changed to 2L / h.

[0041] The multi-layer carbon nanotube narrow ribbon roll obtained in Example 2 has a length of about 1131 m and a width of 43 mm. The surface is flat and wrinkle-free and can be folded arbitrarily. The thickness is uniform, and the thickness deviation at different positions is within the range of ±8 μm. Example 3

[0042] The difference between Example 3 and Example 1 is that the flow rate of the atomizing injection pump is changed to 3000 L / h.

[0043] The length of the multilayer carbon nanotube narrow ribbon roll obtained in Example 3 is about 1089m, its width is 37mm, its surface is flat and wrinkle-free and can be folded arbitrarily, its thickness is uniform, and the thickness deviation at different positions is within the range of ±8μm. Example 4

[0044] The difference between Example 4 and Example 1 is that anhydrous ethanol is replaced with acetone.

[0045] The length of the multilayer carbon nanotube narrow ribbon roll obtained in Example 4 is about 1201m, the width is 40mm, the surface is flat and wrinkle-free and can be folded arbitrarily, the thickness is uniform, and the thickness deviation at different positions is within the range of ±5μm. Example 5

[0046] The difference between Example 5 and Example 1 is that anhydrous ethanol is replaced with N-methylpyrrolidone, and the drying time in step (5) is changed to 12 h.

[0047] The length of the multilayer carbon nanotube narrow ribbon roll obtained in Example 5 is about 1017m, its width is 42mm, its surface is flat without wrinkles and can be folded arbitrarily, its thickness is uniform, and the thickness deviation at different positions is within the range of ±3μm.

[0048] Comparative Example 1

[0049] In Comparative Example 1, a continuous carbon nanotube aerogel was prepared by a floating catalytic chemical vapor deposition method. After being stacked and wound for 15 turns, the wound carbon nanotube aerogel was sprayed with a spray bottle filled with anhydrous ethanol to shrink the carbon nanotube aerogel and make it dense. After drying, a 1×3m carbon nanotube film was obtained, which had a flat surface without wrinkles and could be folded arbitrarily, and the thickness deviation at different positions was within the range of ±15μm.

[0050] Application Example 1

[0051] The multilayer carbon nanotube narrow ribbon roll prepared in Example 1 was cut into multilayer carbon nanotube narrow ribbons of 45×1000 mm by a laser cutting machine, and copper-clad PI was connected to both ends of the multilayer carbon nanotube narrow ribbon as wires, and the wires were connected to an AC power supply, and its heating performance was tested by a thermal imaging tester at a voltage of 10 V. After power was turned on, the multilayer carbon nanotube narrow ribbon heated up in one second, and the entire narrow ribbon area heated up evenly, with a heating temperature deviation of ±2%.

[0052] Application Example 2

[0053] The multilayer carbon nanotube narrow ribbon roll prepared in Example 1 is cut into multilayer carbon nanotube narrow ribbons with a size of 45×1200 mm using a laser cutting machine. After the multilayer carbon nanotube narrow ribbon is completely wrapped around the mobile phone, 4G, 5G and WIFI signals can be completely shielded at the same time.

[0054] Application Example 3

[0055] The multilayer carbon nanotube narrow ribbon roll prepared in Example 1 was cut into appropriate sizes by a laser cutting machine to serve as a current collector, and lithium iron phosphate-carbon nanotube narrow ribbon positive electrode and graphite-carbon nanotube narrow ribbon negative electrode were prepared according to the wet electrode manufacturing process. The lithium iron phosphate-carbon nanotube narrow ribbon positive electrode and the graphite-carbon nanotube narrow ribbon negative electrode were assembled with the separator and then injected with electrolyte to prepare a button battery. The discharge capacity at 0.1 C reached 164 mAhg -1 The capacity retention rate is 99.4% after 500 cycles at 1 C.

[0056] From the data of the above examples and comparative examples, it can be seen that, through a reasonable preparation process, the thickness deviation of the carbon nanotube film prepared in the examples of the present invention is better than that of comparative example 1. In addition, the thickness uniformity effect produced by using N-methylpyrrolidone as the organic solvent and drying time of 12h in Example 5 of the present invention is the most excellent.

[0057] For the comparison results between Comparative Example 1 and Example 1, when the carbon nanotube narrow ribbon is wound 15 times in an overlapping manner, the roller pressure and winding effect on the carbon nanotube film during the preparation process are weakened due to the reduction in the number of overlapping winding layers, which has a certain impact on the structural stability of the carbon nanotube film, thereby reducing the thickness uniformity.

[0058] Comparing Example 5 with Examples 1-4, it can be seen that when N-methylpyrrolidone is used as the organic solvent, the thickness uniformity of the multilayer carbon nanotube narrow ribbon roll is best when the drying time in the vacuum drying oven is longer.

[0059] It can be seen from the data of the above application examples that the multi-layer carbon nanotube narrow ribbon roll prepared in Example 1 of the present invention has good performance effects in the three technical fields of electric heating, wireless signal shielding and battery current collector.

[0060] The technical solutions of the present invention are described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A continuous preparation system for carbon nanotube narrow ribbons, characterized in that: It includes two groups of preparation subsystems, each group of preparation subsystems includes: a tubular furnace, an ultrasonic atomization system, and a roller; the ultrasonic atomization system is arranged directly above the outlet of the tubular furnace; the roller is arranged below the outlet of the tubular furnace, and a polypropylene diaphragm is arranged in the roller; the outlet of the tubular furnace and the roller are connected by a conveyor belt; An open mill is arranged at the center position between the two groups of preparation subsystems. A rubber roller for rolling the film is installed in the open mill. The open mill is connected to the roller through a conveyor belt.

2. A method for continuously preparing carbon nanotube narrow ribbons, characterized in that: The continuous preparation system of the carbon nanotube narrow ribbon as claimed in claim 1 comprises the following steps: S1. Preparing carbon nanotube aerogel by floating catalytic chemical vapor deposition method, comprising: ultrasonically mixing carbon source, catalyst and co-catalyst additives, and then gasifying them by ultrasonic atomization and heating tube, and uniformly injecting them into the furnace of a tube furnace, forming carbon nanotube gas and elastic smoke in the high temperature area of ​​the furnace, and the carbon nanotube gas and elastic smoke flow along the furnace with the inert hot air flow; When the carbon nanotube gas and elastic smoke reach the low-temperature area of ​​the furnace, the elastic smoke adheres to the inner wall of the reactor to form carbon nanotube aerogel and is continuously drawn out from the furnace outlet; S2, using an ultrasonic atomization system to spray an organic solvent directly above the carbon nanotube aerogel extracted from the furnace outlet, wherein the organic solvent completely wets the carbon nanotube aerogel, causing the carbon nanotube aerogel to shrink and compact to form a carbon nanotube narrow ribbon; S3, stacking the carbon nanotube narrow ribbons of the first preparation subsystem on top of the polypropylene diaphragm of the drum through a conveyor belt, rolling the carbon nanotube narrow ribbons through a rubber roller in an open mill to make the carbon nanotube narrow ribbons adhere to the surface of the polypropylene diaphragm, and winding the diaphragm with a single-layer carbon nanotube narrow ribbon on the surface through the drum of the second preparation subsystem to form a single-layer carbon nanotube narrow ribbon roll; S4, stacking the carbon nanotube narrow ribbon of the second preparation subsystem on top of the single-layer carbon nanotube narrow ribbon roll through a conveyor belt, rolling the carbon nanotube narrow ribbon with a rubber roller in an open mill to make the carbon nanotube narrow ribbon adhere to the surface of the single-layer carbon nanotube narrow ribbon roll, and collecting the diaphragm containing two layers of carbon nanotube narrow ribbons by winding the roller of the first preparation subsystem to form a two-layer carbon nanotube narrow ribbon roll; S5. Repeat the operations of step S3 and step S4 to achieve continuous preparation of carbon nanotube narrow ribbon rolls of different thicknesses, and vacuum dry them in a vacuum drying oven at 79-81° C. to obtain a multilayer carbon nanotube narrow ribbon roll.

3. The method for continuously preparing carbon nanotube narrow ribbons according to claim 2, characterized in that: The carbon source in step S1 is one or more of acetone, anhydrous ethanol or toluene, the catalyst is ferrocene, the co-catalyst additive is sulfide, the ultrasonic time of ultrasonic mixing is 5-30min, the flow rate of the atomization injection pump for ultrasonic atomization is 30-80ml / h, the heating tube temperature of the heating tube gasification is 180-250°C, and the temperature of the high temperature zone is 1100-1500°C.

4. The method for continuously preparing carbon nanotube narrow ribbons according to claim 2, characterized in that: The organic solvent in step S2 is one or more of ethanol, acetone, dimethylformamide, dimethyl sulfoxide or N-methylpyrrolidone, the flow rate of the atomization injection pump of the ultrasonic atomization system is 0.5-5L / h, and the width of the carbon nanotube narrow band is 10-60mm.

5. The method for continuously preparing carbon nanotube narrow ribbons according to claim 2, characterized in that: In the step S3, the rolling speeds of the roller, the mixing mill and the conveyor belt of the first group of preparation subsystems are kept consistent, all at 15-150 r / min.

6. The method for continuously preparing carbon nanotube narrow ribbons according to claim 5, characterized in that: In the step S4, the rolling speeds of the roller, the mixing mill and the conveyor belt of the second group of preparation subsystems are kept consistent, all of which are 15-150 r / min, and the rotation direction of the roller and the conveying direction of the conveyor belt are opposite to those of the first group of preparation subsystems.

7. Use of the carbon nanotube narrow ribbon prepared by the continuous preparation system of the carbon nanotube narrow ribbon according to claim 1 and the continuous preparation method of the carbon nanotube narrow ribbon according to any one of claims 2 to 6, characterized in that: include: Applied to electric heating, wireless signal shielding, and battery current collector.

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