Composite magnetic conductive material, preparation method and application thereof

Abstract

The present invention relates to a composite magnetic conductive material, a preparation method thereof and an application. The composite magnetic conductive material comprises a strip-shaped molybdenum oxide matrix, and a polymer layer coated on the outer surface of the molybdenum oxide matrix. Magnetic conductive particles are embedded in the polymer layer, and the magnetic conductive particles are distributed along the circumferential direction of the molybdenum oxide matrix. Among them, the magnetic conductive particles include SnCl2 particles and metallic tin particles. The composite magnetic conductive material of the present invention can not only absorb electromagnetic waves, but also control the passage of electromagnetic waves in the pipeline of the composite magnetic conductive material, has excellent magnetic permeability and is not easily magnetically saturated.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic wave absorption materials, and particularly to a composite magnetic conductive material, a preparation method thereof, and an application thereof. Background Art

[0002] High-efficiency electromagnetic wave absorption materials can be used to manufacture key components such as antennas, attenuators, and filters in various wireless communication devices and Internet of Things devices, improving the performance and cost-effectiveness of the devices. For example, in communication and radar systems, electromagnetic wave absorption materials can effectively reduce signal reflection and interference, improving the performance and reliability of the systems. In addition, in an electromagnetic radiation environment, electromagnetic wave absorption materials can reduce the impact on the surrounding environment and the human body, protecting the ecological environment and human health.

[0003] However, traditional electromagnetic wave absorption materials cannot guide electromagnetic waves, but can only suppress or absorb electromagnetic waves, resulting in limited applications. Summary of the Invention

[0004] Based on this, it is necessary to provide a composite magnetic conductive material, a preparation method thereof, and an application thereof for the above technical problems; this composite magnetic conductive material can not only absorb electromagnetic waves, but also control the passage of electromagnetic waves in the pipeline of the composite magnetic conductive material, has excellent magnetic permeability, and is not easily magnetically saturated.

[0005] The present invention discloses a composite magnetic conductive material, comprising:

[0006] A strip-shaped molybdenum oxide matrix;

[0007] A polymer layer coated on the outer surface of the molybdenum oxide matrix, wherein magnetic conductive particles are embedded inside the polymer layer, and the magnetic conductive particles are distributed along the circumferential direction of the molybdenum oxide matrix. Among them, the magnetic conductive particles include SnCl2 particles and metallic tin particles.

[0008] In one embodiment, the mass ratio of the SnCl2 particles to the metallic tin particles is 1:2 - 1:3.

[0009] In one embodiment, the mass fraction of the magnetic conductive particles in the composite magnetic conductive material is 15% - 25%.

[0010] In one embodiment, the mass fraction of the molybdenum oxide matrix in the composite magnetic conductive material is 20% - 30%.

[0011] In one embodiment, the magnetic conductive particles are distributed on the same circumference around the molybdenum oxide matrix.

[0012] In one embodiment, the polymer layer includes a first polymer layer and a second polymer layer that are sequentially coated on the outer surface of the molybdenum oxide matrix, and the magnetically conductive particles are embedded between the first polymer layer and the second polymer layer.

[0013] In one embodiment, the material of the first polymer layer is selected from at least one of polypyrrole, polyaniline, or polythiophene;

[0014] And / or, the material of the second polymer layer is selected from at least one of polypyrrole, polyaniline, or polythiophene.

[0015] In one embodiment, when the molybdenum oxide matrix is in a circular tubular shape, the length of the molybdenum oxide matrix is 2 μm - 10 μm, the inner diameter is 700 nm - 900 nm, and the outer diameter is 900 nm - 1100 nm.

[0016] In the composite magnetically conductive material provided by the present invention, the SnCl2 particles embedded inside the polymer layer have excellent magnetic permeability, can form an electromagnetic path, guide the transmission direction of electromagnetic waves, and endow the composite magnetically conductive material with excellent electromagnetic energy transmission ability and electromagnetic wave traction ability; the metallic tin particles embedded inside the polymer layer have excellent electrical conductivity and can endow the tube wall of the composite magnetically conductive material with excellent electromagnetic wave shielding effect. Thus, the SnCl2 particles and the metallic tin particles cooperate to control the passage of electromagnetic waves in the pipeline of the composite magnetically conductive material. As a result, the composite magnetically conductive material not only has high insertion loss and can absorb electromagnetic waves, but also can control the passage of electromagnetic waves in the pipeline of the composite magnetically conductive material, has excellent magnetic conduction effect, and is not easily magnetically saturated.

[0017] A preparation method of a composite magnetically conductive material as described above includes the following steps:

[0018] Prepare a strip-shaped molybdenum oxide matrix;

[0019] Form a first polymer layer on the outer surface of the molybdenum oxide matrix to obtain a first intermediate;

[0020] Form magnetically conductive particles on the outer surface of the first polymer layer to obtain a second intermediate;

[0021] Form a second polymer layer on the outer surface of the second intermediate to obtain a composite magnetically conductive material.

[0022] In one embodiment, the step of forming magnetically conductive particles on the outer surface of the first polymer layer includes: mixing the first intermediate with SnCl2 and hydrochloric acid, and sequentially performing ultrasonic treatment, electroreduction treatment, and external magnetic field treatment.

[0023] In one embodiment, the steps of sequentially performing ultrasonic treatment, electroreduction treatment, and external magnetic field treatment satisfy at least one of the following conditions:

[0024] (1) In the ultrasonic treatment step, the frequency is 30 kHz - 35 kHz, the power is 50 W - 100 W, the temperature is 30°C - 45°C, and the time is 0.5 h - 6 h;

[0025] (2) In the electroreduction treatment step, the voltage is 2 V - 3 V, the temperature is 30°C - 45°C, and the time is 0.5 h - 1 h;

[0026] (3) In the magnetic field treatment step, the intensity of the electromagnetic field is 100 mT - 200 mT.

[0027] In one embodiment, the strip-shaped molybdenum oxide matrix is prepared by a hydrothermal method. The steps include: adding an acid to an aqueous solution containing a molybdate and performing a hydrothermal reaction. Among them, the mass ratio of the molybdate to the acid is 1:1 - 4:1, the temperature of the hydrothermal reaction is 200°C - 400°C, and the reaction time is 6 h - 12 h.

[0028] For the preparation method of the composite magnetic conductive material provided by the present invention, first prepare a strip-shaped molybdenum oxide matrix, and then sequentially form a first polymer layer, magnetic conductive particles, and a second polymer layer on the outer surface of the molybdenum oxide matrix, so as to simply prepare a composite magnetic conductive material that can not only absorb electromagnetic waves but also control the transmission of electromagnetic waves in the direction required by actual needs.

[0029] The present invention also discloses an application of the composite magnetic conductive material as described above in an electronic device.

[0030] Since the composite magnetic conductive material of the present invention not only has high insertion loss and can absorb electromagnetic waves, but also has excellent magnetic permeability; when the composite magnetic conductive material is applied to an electronic device, it can improve the performance of the electronic device, enabling the electronic device to not only be applied to a high-frequency magnetic energy change environment with high-energy transmission, but also protect the electronic device from external electromagnetic interference, so as to realize the use of the electronic device in an environment where electromagnetic shielding is required. Description of the Drawings

[0031] Figure 1 It is a cross-sectional schematic diagram of an embodiment of the composite magnetic conductive material of the present invention;

[0032] Figure 2 It is a cross-sectional schematic diagram of another embodiment of the composite magnetic conductive material of the present invention;

[0033] Figure 3 It is a cross-sectional schematic diagram of still another embodiment of the composite magnetic conductive material of the present invention;

[0034] Figure 4 It is a high-magnification scanning electron microscope image of the molybdenum oxide matrix prepared in Example 1;

[0035] Figure 5 High-magnification scanning electron micrograph of the second intermediate prepared in Example 1;

[0036] Figure 6 High-magnification scanning electron micrograph of the composite magnetic conductive material prepared in Example 1;

[0037] Figure 7 Magnetic permeability curve of the composite magnetic conductive material prepared in Example 1;

[0038] Figure 8 Graph showing the relationship between insertion loss and frequency of the composite magnetic conductive material prepared in Example 1 at different thicknesses.

[0039] In the figure: 10, molybdenum oxide matrix; 20, magnetic conductive particles; 30, polymer layer; 301, first polymer layer; 302, second polymer layer. Detailed implementation mode

[0040] For the convenience of understanding the present invention, the present invention will be described in more detail below. However, it should be understood that the present invention can be implemented in many different forms and is not limited to the embodiments or examples described herein. On the contrary, the purpose of providing these embodiments or examples is to make the understanding of the disclosure content of the present invention more thorough and comprehensive.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments or examples and are not intended to limit the present invention. The optional scope of the term "and / or" used herein includes any one of two or more related listed items, and also includes any and all combinations of the related listed items. The any and all combinations include any two related listed items, any more related listed items, or the combination of all related listed items.

[0042] As Figures 1 to 3 As shown, the present invention provides a composite magnetic conductive material, which includes a strip-shaped molybdenum oxide matrix 10 and a polymer layer 30 coated on the outer surface of the molybdenum oxide matrix 10. Magnetic conductive particles 20 are embedded inside the polymer layer 30, and the magnetic conductive particles 20 are distributed along the circumferential direction of the molybdenum oxide matrix 10. Among them, the magnetic conductive particles 20 include SnCl2 particles and metallic tin particles.

[0043] In the composite magnetic conductive material of the present invention, the use of the molybdenum oxide matrix 10 can make the composite magnetic conductive material have good chemical stability and thermal stability, so that the composite magnetic conductive material remains intact in high-temperature and corrosive environments.

[0044] Meanwhile, the SnCl2 particles embedded inside the polymer layer 30 have excellent magnetic permeability, can form an electromagnetic path, guide the transmission direction of electromagnetic waves, and endow the composite magnetic conductive material with excellent electromagnetic energy transmission ability and electromagnetic wave traction ability; the metallic tin particles embedded inside the polymer layer 30 have excellent electrical conductivity and can endow the pipe wall of the composite magnetic conductive material with excellent electromagnetic wave shielding effect. Thus, the SnCl2 particles and the metallic tin particles in the magnetic conductive particles 20 cooperate to control the passage of electromagnetic waves in the pipe of the composite magnetic conductive material, so that the composite magnetic conductive material not only has high insertion loss and can absorb electromagnetic waves, but also can control the passage of electromagnetic waves in the pipe of the composite magnetic conductive material, has excellent magnetic conduction effect and is not prone to magnetic saturation.

[0045] In order to better control the passage of electromagnetic waves in the pipe of the composite magnetic conductive material, in one embodiment, the mass ratio of the SnCl2 particles to the metallic tin particles is 1:2 - 1:3, including but not limited to 1:2, 1:2.2, 1:2.4, 1:2.6, 1:2.8 or 1:3.

[0046] In one embodiment, the mass fraction of the magnetic conductive particles 20 in the composite magnetic conductive material is 15% - 25%, including but not limited to 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24% or 25%, so that the composite magnetic conductive material has both excellent magnetic conduction effect and processing performance.

[0047] In one embodiment, the mass fraction of the molybdenum oxide matrix 10 in the composite magnetic conductive material is 20% - 30%, including but not limited to 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29% or 30%, so that the composite magnetic conductive material has both excellent magnetic conduction effect and forming effect.

[0048] It should be noted that the strip-shaped molybdenum oxide matrix 10 can be a solid structure, a hollow structure or a partially hollow structure. When the strip-shaped molybdenum oxide matrix 10 is in a hollow structure, the polymer layer 30 may extend and fill the head and tail ends of the molybdenum oxide matrix 10; when the strip-shaped molybdenum oxide matrix 10 is in a hollow structure, the strip-shaped molybdenum oxide matrix 10 can be in a round tube shape or a square tube shape. Preferably, the strip-shaped molybdenum oxide matrix 10 is in a round tube shape, so that the polymer layer 30 can coat the outer surface of the molybdenum oxide matrix 10 more uniformly. Furthermore, the magnetic conductive particles 20 can be distributed more uniformly along the circumferential direction of the molybdenum oxide matrix 10.

[0049] When the strip-shaped molybdenum oxide matrix 10 is in a circular tube shape, the length of the molybdenum oxide matrix 10 affects the magnetic conduction effect, and the inner diameter and outer diameter affect the bonding effect between the molybdenum oxide matrix 10 and the polymer layer 30. In one embodiment, the length of the molybdenum oxide matrix 10 is 2 μm - 10 μm, including but not limited to 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm or 10 μm, the inner diameter is 700 nm - 900 nm, including but not limited to 700 nm, 720 nm, 740 nm, 760 nm, 780 nm, 800 nm, 820 nm, 840 nm, 860 nm, 880 nm or 900 nm, and the outer diameter is 900 nm - 1100 nm, including but not limited to 900 nm, 910 nm, 920 nm, 930 nm, 940 nm, 950 nm, 960 nm, 970 nm, 980 nm, 990 nm, 1000 nm or 1100 nm. It can be understood that the inner wall of the molybdenum oxide matrix 10 can also be coated with a polymer layer 30, and magnetic conductive particles 20 can also be embedded in the polymer layer 30.

[0050] When the magnetic conductive particles 20 are embedded in the polymer layer 30, as Figure 1 shown, the magnetic conductive particles 20 can be distributed on the same circumference outside the molybdenum oxide matrix 10, or as Figure 2 shown, be distributed in a discrete state along the circumferential direction of the molybdenum oxide matrix 10. Preferably, the magnetic conductive particles 20 are all distributed on the same circumference outside the molybdenum oxide matrix 10 as Figure 1 shown, so as to improve the electromagnetic passing rate and make the composite magnetic conductive material have a more excellent magnetic conduction effect.

[0051] Furthermore, as Figure 3 shown, the polymer layer 30 includes a first polymer layer 301 and a second polymer layer 302 that are sequentially coated on the outer surface of the molybdenum oxide matrix 10, and the magnetic conductive particles 20 are embedded between the first polymer layer 301 and the second polymer layer 302.

[0052] Among them, the material of the polymer layer 30 is selected from at least one of polypyrrole, polyaniline or polythiophene. When the polymer layer 30 includes a first polymer layer 301 and a second polymer layer 302, the material of the first polymer layer 301 is selected from at least one of polypyrrole, polyaniline or polythiophene, and the material of the second polymer layer 302 is selected from at least one of polypyrrole, polyaniline or polythiophene. The materials of the first polymer layer 301 and the second polymer layer 302 can be the same or different. Since polypyrrole has excellent electrical conductivity, thermal stability and chemical stability and other characteristics, therefore, the material of the polymer layer 30 is selected from polypyrrole, and the materials of the first polymer layer 301 and the second polymer layer 302 are both preferably selected from polypyrrole.

[0053] Preferably, the mass ratio of the polymer layer 30 to the magnetic particles 20 is 2:1 - 4:1, including but not limited to 2:1, 2.5:1, 3:1, 3.5:1, or 4:1.

[0054] The present invention also provides a method for preparing the composite magnetic material as described above, comprising the following steps:

[0055] S10, preparing a strip-shaped molybdenum oxide matrix 10;

[0056] S20, forming a first polymer layer 301 on the outer surface of the molybdenum oxide matrix 10 to obtain a first intermediate;

[0057] S30, forming magnetic particles 20 on the outer surface of the first polymer layer 301 to obtain a second intermediate;

[0058] S40, forming a second polymer layer 302 on the outer surface of the second intermediate to obtain the composite magnetic material.

[0059] In the method for preparing the composite magnetic material provided by the present invention, first a strip-shaped molybdenum oxide matrix 10 is prepared, and then the first polymer layer 301, the magnetic particles 20, and the second polymer layer 302 are sequentially formed on the outer surface of the molybdenum oxide matrix 10, thereby realizing the simple preparation of a composite magnetic material that can not only absorb electromagnetic waves but also control the transmission of electromagnetic waves in the direction required by actual needs.

[0060] In step S10, there is no limitation on the method for preparing the molybdenum oxide matrix 10, as long as the obtained molybdenum oxide matrix 10 is strip-shaped.

[0061] In one embodiment, a strip-shaped molybdenum oxide matrix 10 is prepared by a hydrothermal method. The steps include: adding an acid to an aqueous solution containing molybdate and performing a hydrothermal reaction under an external magnetic field; in order to make the obtained molybdenum oxide matrix 10 be in a circular tubular shape, preferably, the microstructure of the molybdate is circular tubular, the intensity of the magnetic field is 50 mT - 100 mT, including but not limited to 50 mT, 60 mT, 70 mT, 80 mT, 90 mT, or 100 mT, the mass ratio of the molybdate to the acid is 1:1 - 4:1, including but not limited to 1:1, 1.2:1, 1.4:1, 1.6:1, 1.8:1, 2:1, 2.2:1, 2.4:1, 2.6:1, 2.8:1, 3:1, 3.2:1, 3.4:1, 3.6:1, 3.8:1, or 4:1; the temperature of the hydrothermal reaction is 200°C - 400°C, including but not limited to 200°C, 220°C, 240°C, 260°C, 280°C, 300°C, 320°C, 340°C, 360°C, 380°C, or 400°C; the reaction time is 6 h - 12 h, including but not limited to 6 h, 7 h, 8 h, 9 h, 10 h, 11 h, or 12 h.

[0062] In one embodiment, the molybdate includes at least one of ammonium molybdate or sodium molybdate.

[0063] In step S20, in order to better disperse the molybdenum oxide matrix 10, before the step of forming the first polymer layer 301 on the outer surface of the molybdenum oxide matrix 10, the molybdenum oxide matrix 10 is first mixed with hydrochloric acid and subjected to ultrasonic treatment.

[0064] In one embodiment, the step of forming the first polymer layer 301 on the outer surface of the molybdenum oxide matrix 10 includes: mixing the molybdenum oxide matrix 10 with hydrochloric acid and a first polymer monomer, and stirring under an externally applied magnetic field to obtain a first intermediate.

[0065] In one embodiment, the intensity of the externally applied magnetic field is 50 mT - 100 mT, including but not limited to 50 mT, 60 mT, 70 mT, 80 mT, 90 mT or 100 mT.

[0066] In one embodiment, the mass ratio of the first polymer monomer to the molybdenum oxide matrix 10 is 1:2 - 1:5, including but not limited to 1:2, 1:2.25, 1:2.5, 1.2.75, 1:3, 1:3.25, 1:3.5, 1:3.75, 1:4, 1:4.25, 1:4.5, 1:4.75 or 1:5.

[0067] In one embodiment, the temperature of the magnetic stirring is 150 °C - 300 °C, including but not limited to 150 °C, 200 °C, 250 °C or 300 °C, and the time is 1 - 2.5 h, including but not limited to 1 h, 1.5 h, 2 h or 2.5 h.

[0068] In step S30, in one embodiment, the step of forming the magnetic conductive particles 20 on the outer surface of the first polymer layer 301 includes: mixing the first intermediate with SnCl2 and hydrochloric acid, and successively performing ultrasonic treatment, electroreduction treatment and externally applied magnetic field treatment.

[0069] It should be noted that ultrasonic treatment can introduce chloride ions into the conjugated chain structure of the first polymer layer 301, thereby effectively reducing the band gap of the first polymer, increasing the electron mobility, and endowing the first polymer with conductivity. Electroreduction treatment can reduce Sn 2+ ions to metallic Sn, further improving the conductivity of the first polymer. Thus, under the action of the externally applied magnetic field treatment, SnCl2 particles and metallic tin particles can overcome the energy barrier and jump to the surface of the first polymer layer 301.

[0070] In one embodiment, in the ultrasonic treatment step, the frequency is 30 kHz - 35 kHz, including but not limited to 30 kHz, 31 kHz, 32 kHz, 33 kHz, 34 kHz or 35 kHz, the power is 50 W - 100 W, including but not limited to 50 W, 60 W, 70 W, 80 W, 90 W or 100 W, the temperature is 30 °C - 45 °C, including but not limited to 30 °C, 35 °C, 40 °C or 45 °C, and the time is 0.5 h - 6 h, including but not limited to 0.5 h, 0.6 h, 0.7 h, 0.8 h, 0.9 h, 1 h, 2 h, 3 h, 4 h, 5 h or 6 h.

[0071] In order to better control the passage of electromagnetic waves in the pipeline of the composite magnetic conductive material, in one embodiment, in the electroreduction treatment step, the voltage is 2 V - 3 V, including but not limited to 2 V, 2.2 V, 2.4 V, 2.6 V, 2.8 V or 3 V, the temperature is 30 °C - 45 °C, including but not limited to 30 °C, 35 °C, 40 °C or 45 °C, and the time is 0.5 h - 1 h, including but not limited to 0.5 h, 0.6 h, 0.7 h, 0.8 h, 0.9 h or 1 h.

[0072] In one embodiment, in the magnetic field treatment step, the intensity of the electromagnetic field is 100 mT - 200 mT, including but not limited to 100 mT, 110 mT, 120 mT, 130 mT, 140 mT, 150 mT, 160 mT, 170 mT, 180 mT, 190 mT or 200 mT.

[0073] In step S40, the present invention does not limit the manner of forming the second polymer layer 302 on the outer surface of the second intermediate, as long as the second polymer layer 302 can wrap the magnetic conductive particles 20.

[0074] In one embodiment, the step of forming the second polymer layer 302 on the outer surface of the second intermediate includes: mixing and stirring the second intermediate and the second polymer; preferably, the mass ratio of the second intermediate to the second polymer is 1:10 - 1:15, including but not limited to 1:10, 1:11, 1:12, 1:13, 1:14 or 1:15, the stirring temperature is 95 °C - 105 °C, including but not limited to 95 °C, 100 °C or 105 °C, and the time is 1 h - 2 h, including but not limited to 1 h, 1.5 h or 2 h.

[0075] The present invention also provides an application of the composite magnetic conductive material as described above in an electronic device.

[0076] Since the composite magnetic conductive material of the present invention not only has high insertion loss and can absorb electromagnetic waves, but also has excellent magnetic permeability and is not easily magnetically saturated; when the composite magnetic conductive material is applied to an electronic device, the performance of the electronic device can be improved, so that the electronic device can not only be applied to a high-frequency magnetic energy change environment with high-energy transmission, but also make the electronic device immune to the influence of external electromagnetic interference, thereby enabling the electronic device to be used in an environment where electromagnetic shielding is required.

[0077] Hereinafter, the composite magnetic conductive material, its preparation method and application will be further described through the following specific examples.

[0078] Example 1

[0079] Ammonium molybdate, deionized water and nitric acid with a concentration of 8 wt% were mixed according to a mass ratio of 3:1.5:2, and stirred for 20 minutes under an externally applied magnetic field of 75 mT to obtain a homogeneous solution. The obtained solution was transferred to a stainless steel autoclave lined with polytetrafluoroethylene, heated at 200 °C for 12 hours and then naturally cooled. The precipitate was separated, washed with deionized water and ethanol in sequence, and the precipitate was dried at 50 °C for 12 hours to obtain molybdenum oxide matrix 10. The high-magnification scanning electron micrograph of molybdenum oxide matrix 10 is as Figure 4 shown.

[0080] The molybdenum oxide matrix 10 was placed in hydrochloric acid with a concentration of 7 wt% of the same mass for ultrasonic treatment to form a suspension. Pyrrole, ammonium persulfate and hydrochloric acid with a concentration of 7 wt% were mixed according to a mass ratio of 3:1:1, and then added to the suspension. The mass ratio of the suspension to pyrrole was 3:5, and stirred and reacted for 12 hours under an externally applied magnetic field of 75 mT to form a first polypyrrole layer on the outer surface of the molybdenum oxide matrix 10 to obtain a first intermediate.

[0081] SnCl2 and hydrochloric acid with a concentration of 7 wt% were mixed according to a mass ratio of 1:1 to obtain a mixed solution, and then the first intermediate was added to the mixed solution to obtain a reaction solution. Among them, the mass ratio of the first intermediate to the mixed solution was 1:3. The reaction solution was first ultrasonically oscillated for 6 hours, then the reaction solution was added to an electroplating bath, stirred at 100 °C for 1 hour, dried in a vacuum oven at 50 °C, and finally treated under an external electromagnetic field of 150 mT to obtain a second intermediate. The high-magnification scanning electron micrograph of the second intermediate is as Figure 5 shown. The second intermediate and polypyrrole were mixed according to a mass ratio of 1:12 to form a second polypyrrole layer to obtain a composite magnetic conductive material. The high-magnification scanning electron micrograph of the composite magnetic conductive material is as Figure 6 shown. In the composite magnetic conductive material, the mass fraction of the molybdenum oxide matrix 10 is 25%, the mass fraction of the magnetic conductive particles 20 is 20%, the mass ratio of the SnCl2 particles to the metal tin particles is 1:2.5, and the mass fraction of the polymer layer 30 is 55%.

[0082] Comparative Example 1

[0083] Comparative Example 1 was carried out with reference to Example 1, except that the magnetic particles 20 were not introduced. The specific preparation method is as follows:

[0084] Ammonium molybdate, deionized water and nitric acid with a concentration of 8 wt% were mixed in a mass ratio of 3:1.5:2, and magnetically stirred for 20 minutes to obtain a homogeneous solution. The obtained homogeneous solution was transferred to a stainless steel autoclave lined with polytetrafluoroethylene, heated at 200 °C for 12 hours and then naturally cooled. The precipitate was separated, washed with deionized water and ethanol in sequence, and the precipitate was dried at 50 °C for 12 hours to obtain the molybdenum oxide matrix 10.

[0085] The molybdenum oxide matrix 10 was placed in hydrochloric acid with a concentration of 7 wt% of the same mass for ultrasonic treatment to form a suspension. Pyrrole, ammonium persulfate and hydrochloric acid with a concentration of 7 wt% were mixed in a mass ratio of 3:1:1, and then added to the suspension. The reaction was carried out under magnetic stirring for 12 hours to form a polypyrrole layer on the outer surface of the molybdenum oxide matrix 10.

[0086] Comparative Example 2

[0087] Comparative Example 2 was carried out with reference to Example 1, except that the molybdenum oxide matrix 10 was not strip-shaped but irregular in shape. The specific preparation method is as follows:

[0088] Ammonium molybdate, deionized water and nitric acid with a concentration of 3 wt% were mixed in a mass ratio of 3:1.5:2 to obtain a homogeneous solution. The obtained homogeneous solution was transferred to a stainless steel autoclave lined with polytetrafluoroethylene, heated at 200 °C for 12 hours and then naturally cooled. The precipitate was separated, and the precipitate was dried at 50 °C for 12 hours to obtain an irregular molybdenum oxide matrix.

[0089] Comparative Example 3

[0090] Comparative Example 3 was carried out with reference to Example 1, except that the second polypyrrole layer was not formed on the surface of the first intermediate. The specific preparation method is as follows:

[0091] Ammonium molybdate, deionized water and nitric acid with a concentration of 8 wt% were mixed in a mass ratio of 3:1.5:2, and magnetically stirred for 20 minutes to obtain a homogeneous solution. The obtained homogeneous solution was transferred to a stainless steel autoclave lined with polytetrafluoroethylene, heated at 200 °C for 12 hours and then naturally cooled. The precipitate was separated, washed with deionized water and ethanol in sequence, and the precipitate was dried at 50 °C for 12 hours to obtain the molybdenum oxide matrix 10.

[0092] The molybdenum oxide matrix 10 is placed in hydrochloric acid with a concentration of 7 wt% of equal mass and subjected to ultrasonic treatment to form a suspension. Pyrrole, ammonium persulfate, and hydrochloric acid with a concentration of 7 wt% are mixed in a mass ratio of 3:1:1, and then added to the suspension. The reaction is carried out for 12 hours under magnetic stirring to form a first polypyrrole layer on the outer surface of the molybdenum oxide matrix 10, and a first intermediate is obtained.

[0093] SnCl2 and hydrochloric acid with a concentration of 7 wt% are mixed in a mass ratio of 1:1 to obtain a mixed solution. Then, the first intermediate is added to the mixed solution to obtain a reaction solution. Among them, the mass ratio of the first intermediate to the mixed solution is 1:3. The reaction solution is first subjected to ultrasonic oscillation treatment for 6 hours, then the reaction solution is added to an electroplating bath, stirred at 100 °C for 1 hour, dried in a vacuum oven at 50 °C, and finally treated under the condition of an external electromagnetic field of 150 mT to directly obtain a composite magnetic conductive material.

[0094] Test Example 1

[0095] Test the magnetic properties of the composite magnetic conductive materials obtained in Test Example 1 and Comparative Examples 1 to 3. The test method is as follows. The test results are shown in Table 1. The magnetic permeability curve of the composite magnetic conductive material prepared in Example 1 is as Figure 7 shown. The relationship diagram of insertion loss and frequency at different thicknesses is as Figure 8 shown. From Figure 7 it can be seen that in the range of 2 GHz - 4 GHz, the magnetic permeability of the composite magnetic conductive material prepared in Example 1 can reach above 1.2, and the insertion loss of the composite magnetic conductive material at a thickness of 2.2 mm can reach -48.6 dB, having good insertion loss characteristics.

[0096] Absorbing performance test: Refer to "GB / T32596" to test the insertion loss.

[0097] Magnetic permeability test: Refer to "JB / T 13536 - 2018" to test the magnetic permeability.

[0098] Table 1

[0099]

[0100] Example 2

[0101] Example 2 is carried out with reference to Example 1, except that the mass fraction of the magnetic conductive particles 20 in the composite magnetic conductive material is 15%.

[0102] Example 3

[0103] Example 3 is carried out with reference to Example 1, except that the mass fraction of the magnetic conductive particles 20 in the composite magnetic conductive material is 25%.

[0104] Example 4

[0105] Example 4 was carried out with reference to Example 1, except that the mass fraction of the molybdenum oxide matrix 10 in the composite magnetic conductive material was 20%.

[0106] Example 5

[0107] Example 5 was carried out with reference to Example 1, except that the mass fraction of the molybdenum oxide matrix 10 in the composite magnetic conductive material was 30%.

[0108] Example 6

[0109] Example 6 was carried out with reference to Example 1, except that the intensity of the electromagnetic field was 100 mT.

[0110] Example 7

[0111] Example 7 was carried out with reference to Example 1, except that the intensity of the electromagnetic field was 200 mT.

[0112] Example 8

[0113] Example 8 was carried out with reference to Example 1, except that the mass ratio of molybdate to acid was 1:1, the temperature of the hydrothermal reaction was 200 °C, and the reaction time was 6 h.

[0114] Example 9

[0115] Example 9 was carried out with reference to Example 1, except that the mass ratio of molybdate to acid was 4:1, the temperature of the hydrothermal reaction was 400 °C, and the reaction time was 12 h.

[0116] Example 10

[0117] Example 10 was carried out with reference to Example 1, except that the mass ratio of SnCl2 particles to metallic tin particles was 1:2.

[0118] Example 11

[0119] Example 11 was carried out with reference to Example 1, except that the mass ratio of SnCl2 particles to metallic tin particles was 1:3.

[0120] Test Example 2

[0121] With reference to Test Example 1, the magnetic properties of the composite magnetic conductive materials obtained in Examples 2 to 11 were tested, and the test results are shown in Table 2.

[0122] Table 2

[0123]

[0124] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0125] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent should be subject to the appended claims.

Claims

1. A composite magnetic conductive material, characterized in that, Comprising: A strip-shaped molybdenum oxide matrix; A polymer layer coated on the outer surface of the molybdenum oxide matrix, wherein magnetic particles are embedded inside the polymer layer, and the magnetic particles are distributed along the circumferential direction of the molybdenum oxide matrix. Among them, the magnetic particles include SnCl2 particles and metallic tin particles.

2. The composite magnetic conductive material according to claim 1, characterized in that The mass ratio of the SnCl2 particles to the metallic tin particles is 1:2 - 1:

3.

3. The composite magnetic conductive material according to claim 1, wherein The mass fraction of the magnetic particles in the composite magnetic material is 15% - 25%.

4. The composite magnetic conductive material according to claim 1, wherein The mass fraction of the molybdenum oxide matrix in the composite magnetic material is 20% - 30%.

5. The composite magnetic conductive material according to any one of claims 1 to 4, characterized in that The magnetic particles are distributed on the same circumference outside the molybdenum oxide matrix.

6. The composite magnetic conductive material according to claim 5, wherein, The polymer layer includes a first polymer layer and a second polymer layer coated successively on the outer surface of the molybdenum oxide matrix, and the magnetic particles are embedded between the first polymer layer and the second polymer layer.

7. The composite magnetic conductive material according to claim 6, characterized in that The material of the first polymer layer is selected from at least one of polypyrrole, polyaniline, or polythiophene; And / or, the material of the second polymer layer is selected from at least one of polypyrrole, polyaniline, or polythiophene.

8. The composite magnetic conductive material according to claim 1, characterized in that, When the molybdenum oxide matrix is in a circular tubular shape, the length of the molybdenum oxide matrix is 2μm - 10μm, the inner diameter is 700nm - 900nm, and the outer diameter is 900nm - 1100nm.

9. A method for preparing a composite magnetic conductive material according to any one of claims 1 to 8, characterized in that, Including the following steps: Preparing a strip-shaped molybdenum oxide matrix; Forming a first polymer layer on the outer surface of the molybdenum oxide matrix to obtain a first intermediate; Forming magnetic particles on the outer surface of the first polymer layer to obtain a second intermediate; Forming a second polymer layer on the outer surface of the second intermediate to obtain a composite magnetic material.

10. The preparation method of the composite magnetic conductive material according to claim 9, characterized in that, The step of forming magnetic particles on the outer surface of the first polymer layer includes: mixing the first intermediate with SnCl2 and hydrochloric acid, and successively performing ultrasonic treatment, electroreduction treatment, and external magnetic field treatment.

11. The preparation method of the composite magnetic conductive material according to claim 10, characterized in that, The steps of successively performing ultrasonic treatment, electroreduction treatment, and external magnetic field treatment satisfy at least one of the following conditions: (1) In the step of ultrasonic treatment, the frequency is 30kHz - 35kHz, the power is 50W - 100W, the temperature is 30°C - 45°C, and the time is 0.5h - 6h; (2) In the step of electroreduction treatment, the voltage is 2V - 3V, the temperature is 30°C - 45°C, and the time is 0.5h - 1h; (3) In the step of magnetic field treatment, the intensity of the electromagnetic field is 100mT - 200mT.

12. The preparation method of the composite magnetic conductive material according to claim 9, characterized in that, The strip-shaped molybdenum oxide matrix is prepared by a hydrothermal method, and the steps include: adding an acid to an aqueous solution containing molybdate and performing a hydrothermal reaction, wherein the mass ratio of the molybdate to the acid is 1:1 - 4:1, the temperature of the hydrothermal reaction is 200°C - 400°C, and the reaction time is 6h - 12h.

13. Application of a composite magnetic material according to any one of claims 1 to 8 in an electronic device.

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