A method for plasma surface modification of a powder material based on a fibrous support

Abstract

The application provides a powder material plasma surface modification method based on a fiber carrier, and comprises the following steps: uniformly depositing the powder material to be treated on the surface of the fiber carrier by mechanical friction; placing the fiber carrier with the surface deposited with the powder material in a plasma treatment device; setting appropriate power, treatment time and plasma atmosphere; and performing plasma surface modification treatment to obtain the modified powder. The fiber carrier has a rich three-dimensional fiber network structure and a large surface area, can effectively disperse and capture a large number of powder particles, thereby significantly increasing the interaction surface area of the powder particles and the plasma, can significantly improve the plasma surface modification effect, efficiency and consistency of the powder material, and can successfully extend the plasma surface modification technology from the modification application field of planar materials to the modification application field of powder materials.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of plasma surface modification, and particularly relates to a powder material plasma surface modification method based on a fiber carrier. BACKGROUND

[0002] Plasma is the fourth state of matter in addition to solid, liquid and gas. Plasma surface modification is a method that uses plasma equipment to excite a certain gas into a high-energy state of plasma. The plasma jet produced by the plasma equipment contacts the material surface, which triggers a series of chemical and physical processes, thereby changing the physicochemical properties of the material surface. For example, high-energy particles and active substances in the plasma can break the original chemical bonds on the material surface and form new chemical bonds, such as hydroxyl, amino, carboxyl and other active groups. This plasma-mediated chemical reaction can change the chemical composition, structure and properties of the material surface, thereby achieving the purpose of material surface modification and functionalization and expanding the application field of the material.

[0003] Compared with traditional material surface modification methods, plasma surface modification technology has the following significant advantages: 1) multifunctionality: by adjusting the parameters of the plasma, such as the atmosphere, energy and processing conditions, a variety of surface modification effects can be achieved, such as improving the wettability, adhesion, water resistance, corrosion resistance, wear resistance, biocompatibility, antistatic property or optical properties of the material surface; 2) high efficiency: plasma surface modification is a fast and efficient processing method that can change the surface properties of the material in a short time, making it suitable for large-scale production and industrial applications; 3) wide applicability: plasma surface modification is suitable for adjusting and improving the surface properties of different types of materials, including polymers, glass, ceramics, metals, semiconductors, composite materials, biological materials, etc.; 4) green and environmentally friendly: plasma surface modification technology does not require the use of chemical reagents, has low energy consumption and produces little waste, making it an environmentally friendly material surface treatment method that meets the requirements of low carbon and sustainable development. Currently, plasma surface modification technology is widely used in the fields of coatings and coatings, material science and engineering, optoelectronics and optical devices, biomedical engineering, semiconductors, microelectronics and nanotechnology, etc.

[0004] Plasma surface modification technology, as a dry modification process, is generally suitable for treating materials with relatively flat and continuous surfaces, including planar materials (such as films, sheets, substrates), fibrous materials (such as textiles), and complex-shaped materials (such as parts, devices). The surfaces of these materials can be fully contacted with the plasma jet, achieving good surface modification effect. However, when treating powder materials, especially nano-powder, plasma surface modification technology still faces some challenges and limitations. This is mainly because powder materials are usually composed of a large number of tiny micro-nano particles, which have a large specific surface area and tend to aggregate and accumulate. This greatly reduces the effective surface area of the exposed particles, making it difficult for the plasma jet to fully cover and act on the particle surface, thereby greatly limiting the effect of surface modification. Currently, plasma surface modification technology for treating powder materials mainly uses equipment with a rotating plasma cavity. However, despite some progress has been made, there are still some challenges to the problem of nano-powder aggregation, which have not been completely solved.

[0005] On the other hand, traditional wet modification processes, such as solution immersion, surface coating, chemical deposition, and co-precipitation, also have some shortcomings when treating powder materials: first, these methods may require multiple reaction steps and complex reaction conditions, increasing the complexity and technical requirements of the operation; second, wet modification usually requires the use of modifiers or surfactants to promote the reaction or stabilize the dispersion state, but these additives can adversely affect the chemical properties and physical properties of the powder material; in addition, side reactions and by-products may occur during the wet modification process, requiring further treatment and separation steps; in addition, wet modification may require the use of some toxic or harmful chemical reagents, increasing the risk to the environment and health. Therefore, there is an urgent need for an efficient, simple and environmentally friendly modification method that can overcome the above problems and achieve full modification of the surface of powder materials. SUMMARY

[0006] The present application aims to overcome the shortcomings of the prior art and provides a powder material plasma surface modification method based on a fiber carrier.

[0007] The present application provides the following technical solutions:

[0008] The present application provides a powder material plasma surface modification method based on a fiber carrier, comprising the steps of:

[0009] The powder material to be treated is uniformly dispersed and deposited on the surface of the fiber carrier by mechanical friction. The fiber carrier with powder material deposited on the surface is placed in a plasma treatment device, and appropriate power, treatment time and plasma atmosphere are set for plasma surface modification treatment.

[0010] Specifically, the mechanical friction operation includes uniformly spreading the powder material on the surface of the fiber carrier, and then using a suitable tool to apply appropriate pressure and friction motion on the surface of the fiber carrier. Such operation causes mechanical friction between the powder material and the fiber carrier, and by controlling the parameters such as the force, speed and angle of friction, the uniform entrapment and adsorption of the powder material on the rich three-dimensional fiber grid structure on the surface of the fiber carrier is achieved.

[0011] Since the powder material is usually composed of a large number of fine micro-nano particles, which tend to aggregate to form agglomerates and accumulate, resulting in a significant reduction in the effective surface area of the exposed particles, it is difficult for the plasma jet to fully cover and act on the surface of the particles, greatly limiting the effect of surface modification. The present application uniformly deposits the powder material on the surface of the fiber carrier, and utilizes the rich grid structure of the fiber carrier to significantly increase the action area between the powder particles and the plasma jet, thereby improving the surface modification effect. Therefore, the present application achieves uniform dispersion of the powder material on the fiber carrier through simple operation, successfully solving the technical problem of uniform dispersion of the powder material in the traditional plasma surface modification technology, which is an advantage not possessed by the prior art.

[0012] Further, the method further comprises the steps of: eluting the modified powder attached to the surface of the fiber carrier into a solvent to form a powder dispersion liquid, depositing the powder dispersion liquid onto the fiber carrier by suction filtration, and placing the fiber carrier with the powder material deposited on the surface into a plasma treatment device, setting appropriate power, treatment time and plasma atmosphere, and performing secondary plasma surface modification treatment.

[0013] The powder material to be treated is uniformly deposited on the surface of the fiber carrier by mechanical friction, the fiber carrier with the powder material deposited on the surface is placed into a plasma treatment device, appropriate power, treatment time and plasma atmosphere are set, plasma is used to modify the surface of the powder material, the modified powder attached to the surface of the fiber carrier is eluted into a suitable solvent to form a powder dispersion liquid, the powder dispersion liquid is deposited onto the fiber carrier by suction filtration, and then secondary plasma surface modification treatment is performed.

[0014] The modified powder is again attached to the fiber carrier for secondary plasma surface modification treatment, which can further increase the modification effect of the powder material.

[0015] Further, the plasma surface modification treatment specifically comprises: spraying plasma onto the powder attached to the surface of the fiber carrier to make the plasma fully contact the powder particles and perform plasma surface modification on the powder.

[0016] Further, the plasma device is set at a power of 50-300 W and a processing time of 1-5 min.

[0017] Further, the plasma atmosphere comprises any one or several of air, oxygen, nitrogen, carbon dioxide, hydrogen, ammonia, helium, argon, carbon tetrafluoride, carbon disulfide, sulfur dioxide, hydrogen sulfide, methane, etc.

[0018] Further, the fiber carrier is filter paper, filter cloth or other material with abundant fiber network and pore structure.

[0019] Further, the powder material is any one of carbon material powder, polymer powder, oxide powder, metal powder, semiconductor powder, ceramic powder, nanometer powder, fiber powder, inorganic material powder, organic material powder and composite material powder.

[0020] Further, the powder material is multi-walled carbon nanotube powder, single-walled carbon nanotube powder, carbon fiber powder, acetylene black powder, silicon nitride powder, polyvinylidene fluoride powder or fumed silica powder.

[0021] Further, the particle size of the powder material is 1 nm to 1000 μm.

[0022] The present application has the following advantages:

[0023] 1. The traditional plasma surface modification technology faces challenges such as large specific surface area of powder particles, easy agglomeration and accumulation when treating powder materials. The present application utilizes the abundant three-dimensional fiber network structure and large surface area of the fiber carrier surface to effectively disperse and capture a large number of powder particles, thereby significantly increasing the interaction surface area of the powder particles and the plasma, significantly improving the plasma surface modification effect, efficiency and consistency of the powder material, and successfully extending the application of the plasma surface modification technology from planar materials to powder material modification.

[0024] 2. The plasma surface modification method for powder materials based on the fiber carrier adopted in the present application is a dry modification process, which overcomes the shortcomings of the traditional wet modification process. Firstly, the method does not require additional chemical reagents, can maintain the high purity and purity of the powder material, avoids the influence of additives such as modification agents or surfactants and by-product residues on the performance of the powder material, and simplifies the operation process. Secondly, dry modification does not require heating or solvent evaporation, saving energy and process cost, and improving production efficiency. In addition, the process of dry modification is relatively stable, which can realize the consistency and repeatability of the modification effect. At the same time, since no toxic or harmful chemicals are used, the method is more environmentally friendly. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without any creative effort.

[0026] Figure 1 A real photo of the fiber carrier with the surface deposited with the multi-walled carbon nanotube powder in Embodiment 1 of the present application;

[0027] Figure 2 An optical micrograph of the fiber carrier with the surface deposited with the multi-walled carbon nanotube powder in Embodiment 1 of the present application;

[0028] Figure 3 A scanning electron microscope (SEM) photo of the fiber carrier with the surface deposited with the multi-walled carbon nanotube powder in Embodiment 1 of the present application;

[0029] Figure 4 A comparison photo of the hydrophobic multi-walled carbon nanotube powder respectively without plasma treatment (left photo), directly treated by plasma (middle photo) and treated by plasma after being deposited on the surface of the fiber carrier (right photo), and then respectively dispersed in deionized water and taken after standing for 6 hours in Embodiment 1 of the present application;

[0030] Figure 5 A photo of the water contact angle measurement of the tablet of the unmodified multi-walled carbon nanotube powder in Embodiment 1 of the present application;

[0031] Figure 6 A photo of the water contact angle measurement of the tablet of the multi-walled carbon nanotube powder treated by the plasma surface modification of the fiber carrier in Embodiment 1 of the present application;

[0032] Figure 7 A comparison photo of the hydrophobic carbon fiber powder respectively without plasma treatment (left photo), directly treated by plasma (middle photo) and treated by plasma after being deposited on the surface of the fiber carrier (right photo), and then respectively dispersed in deionized water and taken after standing for 6 hours in Embodiment 1 of the present application;

[0033] Figure 8 A comparison photo of the hydrophobic acetylene black powder respectively without plasma treatment (left photo), directly treated by plasma (middle photo) and treated by plasma after being deposited on the surface of the fiber carrier (right photo), and then respectively dispersed in deionized water and taken after standing for 6 hours in Embodiment 1 of the present application;

[0034] Figure 9The contrast photos of the hydrophobic silicon nitride powder in the embodiment 1 of the present application, which is not treated by plasma (left photo), directly treated by plasma (middle photo) and treated by plasma after being deposited on the surface of the fiber carrier (right photo), are taken after being dispersed in deionized water and standing for 6 hours respectively;

[0035] Figure 10 The contrast photos of the hydrophobic polyvinylidene fluoride powder in the embodiment 1 of the present application, which is not treated by plasma (left photo), directly treated by plasma (middle photo) and treated by plasma after being deposited on the surface of the fiber carrier (right photo), are taken after being dispersed in deionized water respectively;

[0036] Figure 11 The contrast photos of the hydrophobic fumed silica powder in the embodiment 1 of the present application, which is not treated by plasma (left photo), directly treated by plasma (middle photo) and treated by plasma after being deposited on the surface of the fiber carrier (right photo), are taken after being dispersed in deionized water respectively;

[0037] Figure 12 The contrast photos of the hydrophobic multi-walled carbon nanotube powder in the embodiment 2 of the present application, which is treated by fiber carrier plasma once (left photo) or twice (right photo), are taken after being dispersed in deionized water and standing for 72 hours respectively;

[0038] Figure 13 The contrast photos of the hydrophobic single-walled carbon nanotube powder in the embodiment 2 of the present application, which is not treated by plasma (left photo), directly treated by plasma twice (middle photo) and treated by plasma twice after being deposited on the surface of the fiber carrier (right photo), are taken after being dispersed in deionized water respectively. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0040] Embodiment 1

[0041] In this embodiment, cellulose filter paper is used as a fiber carrier, and different powder materials are modified. Hydrophobic multi-walled (inner diameter: 5-12 nm, outer diameter: 30-50 nm, length: 0.5-2 μm) or single-walled (inner diameter: 0.8-1.6 nm, outer diameter: 1-2 nm, length: 1-2 μm) carbon nanotubes (belonging to one-dimensional nanomaterials), carbon fibers (outer diameter: 200-600 nm, length: 5-50 μm, belonging to fiber materials), acetylene black (Kappa 100 type, belonging to conductive materials), silicon nitride (particle size: 20 nm, belonging to inorganic ceramic materials), polyvinylidene fluoride (PVDF 900 type, belonging to organic polymer materials), and fumed silica (particle size: 7-40 nm, belonging to inorganic oxide materials) are dispersed on the surface of the fiber carrier by mechanical rubbing, and then the surface of the powder materials is modified by oxygen plasma treatment to achieve uniform dispersion of the powder in deionized water.

[0042] The specific modification steps are as follows:

[0043] (1) Place 0.02 g of powder material on a filter paper with a diameter of 7 cm, wear latex gloves, and use fingers to evenly spread the powder particles on the surface of the filter paper by mechanical rubbing;

[0044] (2) Place the filter paper with hydrophobic powder deposited on the surface in a plasma cleaning machine, use pure oxygen as the plasma atmosphere, set the power to 100 W for plasma modification treatment, and the treatment time is 2 min.

[0045] Roll the filter paper after plasma treatment into a hollow roll and place it in a plastic centrifuge tube with a capacity of 50 mL, ensuring that the filter paper is tightly attached to the inner wall of the centrifuge tube. Add an appropriate amount of deionized water to the centrifuge tube, insert the homogenizer head of the high-speed homogenizer into the filter paper roll in the centrifuge tube, and rotate at high speed. The hydrophilic powder modified on the surface of the filter paper is washed and eluted into the water by the high-speed water flow formed between the rotor and stator of the homogenizer head, and is uniformly dispersed. Let stand for 6 hours.

[0046] And as a comparison, the powder materials are not subjected to plasma treatment, and the powder materials are directly subjected to plasma treatment, and are dispersed in deionized water by a high-speed homogenizer. After standing for 6 hours, the comparison results are photographed.

[0047] Figures 1-11 The experimental results of this embodiment are shown:

[0048] Specifically, from Figures 1-3 It can be seen that the multi-walled carbon nanotube powder is evenly dispersed and attached to the three-dimensional fiber network structure on the surface of the filter paper by mechanical rubbing.

[0049] FromFigure 4 It can be seen that the left figure is a multi-walled carbon nanotube powder without plasma treatment; the middle figure is a multi-walled carbon nanotube powder directly treated by plasma; and the right figure is a multi-walled carbon nanotube powder deposited on the surface of filter paper and then treated by plasma. By comparing these photos, it can be obviously observed that in the first two cases, the multi-walled carbon nanotubes cannot be stably dispersed in water and settle at the bottom of the test tube, while the multi-walled carbon nanotubes treated by the plasma surface modification of the fiber carrier can be stably suspended in the aqueous phase, indicating that the method successfully realizes the surface hydrophilization modification of the hydrophobic multi-walled carbon nanotubes.

[0050] Figure 5 Photos of water contact angle measurement of hydrophobic multi-walled carbon nanotube powder after tabletting are shown. It can be observed that the water droplets form a larger contact angle on the surface of the multi-walled carbon nanotube powder, which indicates that the unmodified multi-walled carbon nanotubes have strong hydrophobicity, making it difficult for the surface to be wetted by water.

[0051] Figure 6 Photos of water contact angle measurement of multi-walled carbon nanotube powder after tabletting after the plasma surface modification of the fiber carrier are shown. It can be observed that the water droplets form a smaller contact angle on the surface of the carbon nanotube powder, which indicates that the surface of the modified multi-walled carbon nanotubes has better hydrophilicity, making it easier to form wetting with water.

[0052] Figure 7 Comparison results of hydrophobic carbon fiber powder after different treatments dispersed in deionized water by a high-speed homogenizer and photographed after standing for 6 hours are shown. From left to right, the left figure is carbon fiber powder without plasma treatment; the middle figure is carbon fiber powder directly treated by plasma; and the right figure is carbon fiber powder deposited on the surface of filter paper and then treated by plasma. The results show that, compared to the first two cases, the hydrophilic surface modification of the hydrophobic carbon fiber powder and its good dispersion in the aqueous phase are successfully realized by the plasma surface modification method of the fiber carrier.

[0053] Figure 8 Comparison results of hydrophobic acetylene black powder after different treatments dispersed in deionized water by a high-speed homogenizer and photographed after standing for 6 hours are shown. From left to right, the left figure is acetylene black powder without plasma treatment; the middle figure is acetylene black powder directly treated by plasma; and the right figure is acetylene black powder deposited on the surface of filter paper and then treated by plasma. The results show that, compared to the first two cases, the hydrophilic surface modification of the hydrophobic acetylene black powder and its good dispersion in the aqueous phase are successfully realized by the plasma surface modification method of the fiber carrier.

[0054] Figure 9The contrast results of hydrophobic silicon nitride powder dispersed in deionized water by high-speed homogenizer after different treatments are shown. From left to right, the left picture is the silicon nitride powder without plasma treatment; the middle picture is the silicon nitride powder directly treated by plasma; and the right picture is the silicon nitride powder deposited on the surface of filter paper and then treated by plasma. The results show that in the first two cases, the silicon nitride cannot be stably dispersed in water, but deposited at the bottom of the test tube. However, the silicon nitride powder treated by plasma on the surface of the fiber carrier can be stably suspended in the aqueous phase, so that the silicon nitride aqueous dispersion shows the characteristic light blue opalescence of colloidal system.

[0055] Figure 10 The contrast results of hydrophobic polyvinylidene fluoride powder dispersed in deionized water by high-speed homogenizer after different treatments are shown. From left to right, the left picture is the polyvinylidene fluoride powder without plasma treatment; the middle picture is the polyvinylidene fluoride powder directly treated by plasma; and the right picture is the polyvinylidene fluoride powder deposited on the surface of filter paper and then treated by plasma. The results show that in the first two cases, the polyvinylidene fluoride cannot be dispersed in water, but floats on the water surface. However, the polyvinylidene fluoride powder treated by plasma on the surface of the fiber carrier can be well dispersed in the aqueous phase.

[0056] Figure 11 The contrast results of hydrophobic fumed silica powder dispersed in deionized water by high-speed homogenizer after different treatments are shown. From left to right, the left picture is the fumed silica powder without plasma treatment; the middle picture is the fumed silica powder directly treated by plasma; and the right picture is the fumed silica powder deposited on the surface of filter paper and then treated by plasma. The results show that in the first two cases, the fumed silica cannot be dispersed in water, but floats on the water surface. However, the fumed silica powder treated by plasma on the surface of the fiber carrier can be well dispersed in the aqueous phase.

[0057] Example 2

[0058] In this example, cellulose filter paper is used as the fiber carrier. First, the hydrophobic multi-walled or single-walled carbon nanotube powder is dispersed on the surface of the fiber carrier by mechanical friction. Then, the carbon nanotube powder is treated by oxygen plasma for the first time to modify the surface to be hydrophilic, and the powder is uniformly dispersed in deionized water. After that, the aqueous dispersion of the carbon nanotube is deposited on the surface of the filter paper by suction filtration. After drying the filter paper, the carbon nanotube powder is treated by oxygen plasma for the second time to further increase the surface hydrophilic modification effect of the carbon nanotube and the dispersion stability in the aqueous phase.

[0059] The specific steps are as follows:

[0060] (1) Put 0.02 g of hydrophobic carbon nanotube powder material on a filter paper with a diameter of 7 cm, wear a latex glove, and evenly spread the powder particles on the surface of the filter paper by mechanical friction with fingers;

[0061] (2) Place the filter paper with hydrophobic carbon nanotube powder deposited on the surface in a plasma cleaning machine, use pure oxygen as the plasma atmosphere, and set the power to 100 W for plasma treatment, with a treatment time of 2 min;

[0062] (3) Roll the filter paper after plasma treatment into a hollow roll and place it in a plastic centrifuge tube with a capacity of 50 mL, ensuring that the filter paper is tightly attached to the inner wall of the centrifuge tube. Add an appropriate amount of deionized water to the centrifuge tube. Insert the homogenizer head of the high-speed homogenizer into the filter paper roll in the centrifuge tube and perform high-speed rotation. The hydrophilic carbon nanotube powder modified on the surface of the filter paper is washed and eluted into the water by the high-speed water flow formed between the rotor and stator of the homogenizer head, and is uniformly dispersed;

[0063] (4) Pour the above-mentioned water dispersion of carbon nanotubes into a suction filter funnel and perform suction filtration to make the carbon nanotubes disperse and deposit on the surface of the filter paper. Then place the filter paper in an oven at a temperature of 50°C for drying for 20 min, and then place it in a plasma cleaning machine for a second oxygen plasma surface modification treatment, with a treatment power of 100 W and a treatment time of 2 min.

[0064] Roll the filter paper after step (4) treatment into a hollow roll and place it in a plastic centrifuge tube with a capacity of 50 mL, ensuring that the filter paper is tightly attached to the inner wall of the centrifuge tube. Add an appropriate amount of deionized water to the centrifuge tube. Insert the homogenizer head of the high-speed homogenizer into the filter paper roll in the centrifuge tube and perform high-speed rotation, and the hydrophilic carbon nanotube powder modified on the surface of the filter paper is washed and eluted into the water by the high-speed water flow formed between the rotor and stator of the homogenizer head, and is uniformly dispersed, and is left to stand for 72 h, with the dispersion after step (3) treatment left to stand for 72 h as a comparison.

[0065] Figure 12The contrast results of hydrophobic multi-walled carbon nanotube powder after one or two fiber carrier plasma treatments are shown. The left image shows that the multi-walled carbon nanotube powder is deposited on the surface of filter paper by rubbing method, and after the first oxygen plasma treatment, it is dispersed in deionized water, and part of the multi-walled carbon nanotube is seen to settle at the bottom of the test tube; the right image shows that the multi-walled carbon nanotube powder is deposited on the surface of filter paper by rubbing method, and after the first oxygen plasma treatment, it is dispersed in deionized water, and then deposited on the surface of filter paper by suction filtration method, the filter paper is dried, and then after the second oxygen plasma treatment, it is dispersed in deionized water again, and the multi-walled carbon nanotube is still stably dispersed in water. The results show that the surface hydrophilic modification effect and water dispersion stability of multi-walled carbon nanotubes can be further increased by two fiber carrier oxygen plasma treatments.

[0066] Figure 13 The contrast results of hydrophobic multi-walled carbon nanotube powder after one or two fiber carrier plasma treatments are shown. The left image shows that the multi-walled carbon nanotube powder is deposited on the surface of filter paper by rubbing method, and after the first oxygen plasma treatment, it is dispersed in deionized water, and part of the multi-walled carbon nanotube is seen to settle at the bottom of the test tube; the right image shows that the multi-walled carbon nanotube powder is deposited on the surface of filter paper by rubbing method, and after the first oxygen plasma treatment, it is dispersed in deionized water, and then deposited on the surface of filter paper by suction filtration method, the filter paper is dried, and then after the second oxygen plasma treatment, it is dispersed in deionized water again, and the multi-walled carbon nanotube is still stably dispersed in water. The results show that the surface hydrophilic modification effect and water dispersion stability of multi-walled carbon nanotubes can be further increased by two fiber carrier oxygen plasma treatments.

[0067] In addition, the modification of the powder material in the present application is not limited to hydrophilic modification. When other gases are used as the plasma atmosphere, different functional surface modification of the powder can also be achieved. For example, using nitrogen gas for plasma treatment can introduce nitrogen-containing functional groups on the surface of the material; using a mixture of hydrogen and nitrogen gas for plasma treatment can introduce amino groups; using fluorine-containing gas for plasma treatment can introduce fluorine groups, thereby imparting water-repellent properties to the material. These surface modification methods can adjust the gas combination and treatment conditions as needed to achieve specific chemical functionalization effects.

[0068] The present application utilizes the rich three-dimensional fiber network structure and large surface area of the fiber carrier, which can effectively disperse and capture a large number of powder particles, thereby significantly increasing the interaction surface area between the powder particles and the plasma, and significantly improving the plasma surface modification effect, efficiency and consistency of the powder material, and successfully expanding the plasma surface modification technology from planar materials to the modification application field of powder materials.

[0069] The above merely provides the preferred embodiment of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for plasma surface modification of a powder material based on a fibrous support, characterized in that, The method comprises the steps of: The powder material to be treated is uniformly deposited on the surface of the fiber carrier by mechanical friction, the fiber carrier with the powder material deposited on the surface is placed in a plasma treatment device, appropriate power, treatment time and plasma atmosphere are set, plasma surface modification treatment is carried out, and the modified powder is obtained; The power of the plasma device is 50-300 W, and the treatment time is 1-5 min; The plasma atmosphere includes any one or several of air, oxygen, nitrogen, carbon dioxide, hydrogen, ammonia, helium, argon, carbon tetrafluoride, carbon disulfide, sulfur dioxide, hydrogen sulfide and methane gas; The fiber carrier is a filter paper interwoven by fiber materials.

2. The fiber support-based powder material plasma surface modification method according to claim 1, characterized by: The method further comprises the steps of: eluting the modified powder attached to the surface of the fiber carrier into a solvent to form a powder dispersion liquid, depositing the powder dispersion liquid on the fiber carrier by suction filtration, and placing the fiber carrier with the powder material deposited on the surface in a plasma treatment device after drying, setting appropriate power, treatment time and plasma atmosphere, and carrying out secondary plasma surface modification treatment.

3. The fiber support-based powder material plasma surface modification method according to claim 1, characterized by: The specific steps of modifying the powder material by plasma are: spraying plasma onto the powder attached to the surface of the fiber carrier to make the plasma fully contact the powder particles and modify the surface of the powder by plasma.

4. The fiber support-based powder material plasma surface modification method according to claim 1, characterized by: The powder material is any one of carbon material powder, polymer powder, oxide powder, metal powder, semiconductor powder, ceramic powder, nanometer powder, fiber powder and composite material powder.

5. The fiber support-based powder material plasma surface modification method according to claim 1, wherein: The powder material is multi-walled carbon nanotube powder, single-walled carbon nanotube powder, carbon fiber powder, acetylene black powder, silicon nitride powder, polyvinylidene fluoride powder or fumed silica powder.

6. The fiber support-based powder material plasma surface modification method according to claim 1, characterized by: The particle size of the powder material is 1 nm to 1000 μm.

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