CN115433549A - Composite microspheres with dual functions of microwave absorption and thermal management, preparation method and application thereof - Google Patents

Abstract

The invention discloses a composite microsphere with wave absorbing and heat management functions, a preparation method and application thereof. The preparation method comprises the following steps: s1: mixing and stirring the acid-activated attapulgite, the Ni-Co magnetic particles and the carbon nanotube slurry with sodium hexametaphosphate and water, and performing ultrasonic treatment to obtain an acid-activated attapulgite-Ni-Co magnetic particle-carbon nanotube suspension; s2: the suspension is subjected to spray drying to construct composite microspheres; s3: calcining the composite microspheres; s4: vacuum impregnation is carried out on the composite microspheres and the phase-change material to obtain composite microspheres with wave absorbing and heat management functions; wherein, the preparation steps of the Ni-Co magnetic particles are as follows; weighing hexadecyl trimethyl ammonium bromide, naOH, cobalt acetate tetrahydrate and nickel acetate tetrahydrate, adding the weighed materials into an ethylene glycol solution, stirring and carrying out ultrasonic treatment to obtain a mixed suspension, and carrying out hydrothermal synthesis; and collecting a black powder product after the reaction is finished, and washing and drying the black powder product. The material can simultaneously realize the dual functions of wave absorption and heat management.

Description

Composite microspheres with dual functions of microwave absorption and thermal management, preparation method and application thereof

technical field

The invention relates to the technical field of chemical materials, in particular to composite microspheres with dual functions of wave absorption and thermal management, and a preparation method and application thereof.

Background technique

Electromagnetic radiation pollution has become another important pollution source that affects the health of urban residents after wastewater, waste gas, noise, and solid waste pollution, and poses a huge threat to human health. With the development of wireless communication, highly integrated, high-speed, and miniaturized wireless communication devices are often affected by unwanted electromagnetic interference effects and significant heat generation. Therefore, materials with both excellent thermal management properties and excellent EMI shielding properties have attracted extensive attention in modern wireless communications, autonomous vehicles, and portable devices. Phase change materials can store and release energy in the form of latent heat while maintaining a constant temperature. Because of their ultra-high volumetric energy density and narrow temperature distribution range during energy conversion and utilization, they have been used in thermal energy storage and thermal management of electronic equipment. It has been widely used in different fields, and is recognized as the best temperature control material for thermal protection and electronic cooling systems.

Most of the reported composite phase change materials and microwave absorbing materials for electronic devices are focused on single-purpose projects, and there are common problems such as complicated preparation methods, poor mechanical strength, and low economic benefits. In smart devices with small size, light weight, and high energy density, it becomes very important to develop protection systems with dual functions of EMI shielding and thermal management. However, designing flexible, lightweight, and small-volume all-in-one materials with efficient EMI shielding and thermal management functions remains a great challenge.

Contents of the invention

The object of the present invention is to propose a composite microsphere with dual functions of wave absorption and heat management, its preparation method and application, aiming at the above-mentioned deficiencies of the prior art.

A method for preparing composite microspheres with dual functions of wave absorption and heat management of the present invention comprises the following steps:

S1: Acid-activated attapulgite, Ni-Co magnetic particles, carbon nanotube slurry, sodium hexametaphosphate and water were mixed and stirred, and ultrasonically obtained to obtain an acid-activated attapulgite-Ni-Co magnetic particle-carbon nanotube suspension;

S2: Acid-activated attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres were constructed by spray drying the suspension;

S3: calcining to obtain attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres;

S4: Vacuum impregnation of composite microspheres and phase change materials to obtain composite microspheres with dual functions of microwave absorption and thermal management;

Wherein, the preparation steps of Ni-Co magnetic particles are as follows; weigh cetyltrimethylammonium bromide, NaOH, cobalt acetate tetrahydrate and nickel acetate tetrahydrate, add them to ethylene glycol solution, stir, and ultrasonically obtain a mixed suspension, The mixed suspension was subjected to hydrothermal synthesis; after the reaction, the black powder product was collected, washed with deionized water or absolute ethanol, and dried.

Further, in the preparation method of Ni-Co magnetic particles, the cetyltrimethylammonium bromide, NaOH, cobalt acetate tetrahydrate, nickel acetate tetrahydrate and ethylene glycol are calculated in parts by weight as follows:

Hexadecyltrimethylammonium bromide: 2 to 6 parts

NaOH: 1 to 4 parts

Cobalt acetate tetrahydrate: 0.2 to 0.5 parts

Nickel acetate tetrahydrate: 0.5 to 3 parts

Ethylene glycol: 30-50 parts.

Further, in the preparation method of Ni-Co magnetic particles, the stirring speed is 500-1000r/min, the stirring time is 30-60min; the ultrasonic treatment time is 30-60min; the hydrothermal synthesis temperature is 180-200°C , the hydrothermal synthesis time is 6 ~ 12h.

Further, the attapulgite raw ore is soaked in acid solution to obtain acid-activated attapulgite. The acid activation process is: soaking in acid solution, solid-liquid separation, washing, and drying; wherein the acid solution is H ⁺ concentration of 1 to 4mol/L The aqueous solution of inorganic strong acid is soaked in stirring, the stirring speed is 500-1000r/min, the soaking temperature is 60-90°C, and the soaking time is 40-120min.

Further, in step S1, the acid-activated attapulgite, Ni-Co magnetic particles, carbon nanotube slurry, sodium hexametaphosphate and water are calculated in parts by weight as follows:

Acid-activated attapulgite: 0.5 to 2 parts

Ni-Co magnetic particles: 1 to 5 parts

Carbon nanotube slurry: 10-30 parts, the concentration of carbon nanotube slurry is 10%

Sodium hexametaphosphate: 0.2 to 1 part

Water: 30-80 parts.

Further, in step S1, the stirring speed is 600-1000r/min, and the stirring time is 30-60min; the ultrasonic treatment time is 40-80min; 3.0, the fan frequency is set at 35.00Hz, the inlet air temperature is set at 150-180°C, and the creep speed is 1-6RPM.

Further, in step S3, the calcination temperature is 300-400° C., the calcination time is 1-4 h, and the calcination atmosphere is an inert gas.

Further, in step S4, the relationship between the amount of the composite microspheres and the phase change material is: 40-60wt.%: 40-60wt.%; vacuum impregnation is performed at room temperature for 10-50min, and then at 40-90°C Vacuumize for 10-50 minutes.

A composite microsphere with dual functions of wave absorption and heat management prepared by the above-mentioned preparation method.

The application of the above-mentioned composite microspheres with dual functions of wave absorption and thermal management is used for electromagnetic interference shielding and thermal energy regulation of high-end electronic equipment.

The present invention prepares Ni-Co magnetic particles of suitable size through hydrothermal synthesis, and then soaks the attapulgite in an acid solution to unbundle and purify the attapulgite to obtain acid-activated attapulgite, and constructs the attapulgite-Ni- Co magnetic particle-carbon nanotube composite microspheres, the phase change material is encapsulated in the rigid structure of the composite microspheres to prevent leakage, and a composite microsphere material with dual functions of wave absorption and thermal management is obtained.

The invention utilizes the special properties of minerals in the field of heat storage and research on microwave-absorbing materials, realizes excellent thermal management performance through phase-change materials, and realizes microwave absorption performance through microsphere structures, dielectric loss materials and magnetic loss materials. Therefore, using attapulgite as the matrix material to adjust the dielectric constant of the composite material, carbon nanotubes as the dielectric loss material and magnetic metal alloy as the magnetic loss material, the composite microspheres are constructed to make the intrinsic impedance and free space impedance of the material as close as possible. It is possible to achieve a balance. The introduction of attapulgite can adjust the complex dielectric constant of the composite material to an appropriate range to ensure the balance of the impedance matching characteristics of the material. The porous structure of the composite microspheres can make the incident electromagnetic waves reflect multiple times inside the spheres. Loss, combined with the strong magnetic loss ability of magnetic metal particles and the synergistic effect of multiple loss mechanisms, the composite material has superior wave-absorbing properties.

The attapulgite-Ni-Co magnetic particle-carbon nanotube composite microsphere prepared by the present invention has a high specific surface area and a porous structure, and can be effectively encapsulated by various interactions such as capillary force, surface tension, hydrogen bond and van der Waals force phase change material. Moreover, the attapulgite-Ni-Co magnetic particle-carbon nanotube composite microsphere prepared by the present invention has lower density than traditional wave-absorbing materials, good wave-transmitting performance, and its unique structural characteristics are also beneficial to the loss of electromagnetic waves. Moreover, the attapulgite used in the present invention also has special properties such as small size effect, quantum size effect and surface interface effect, making full use of the special properties of attapulgite and integrating the characteristics and advantages of minerals, dielectric loss materials, and magnetic loss materials And functional design, the constructed composite microsphere material has dual functions of microwave absorption and thermal management.

The attapulgite-Ni-Co magnetic particle-carbon nanotube composite microsphere constructed by the present invention is in the range of 2-18GHz. When the thickness is only 1.7mm, the effective wave-absorbing bandwidth can reach 5.54GHz, and the thickness is 1.6mm. , the maximum reflection loss value of 21.81dB is reached at 15.17GHz.

The attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres constructed by the present invention are vacuum-impregnated with paraffin to prepare a microsphere-based composite phase change material. The loading capacity of the composite microspheres to paraffin is about 47.8%, which has superior thermal energy storage capacity. The material can realize the dual functions of wave absorption and thermal management at the same time, which is of great significance for the simultaneous realization of electromagnetic interference shielding and thermal energy regulation of high-end electronic equipment.

Description of drawings

Fig. 1 is the scanning electron micrograph of the Ni-Co magnetic particle that embodiment 1 prepares;

Fig. 2 is the scanning electron micrograph of the composite microsphere prepared after the acid-activated attapulgite-Ni-Co magnetic particles-carbon nanotube suspension spray-dried prepared in Example 1;

Fig. 3 is the scanning electron micrograph of the attapulgite-Ni-Co magnetic particle-carbon nanotube composite microsphere after the calcination prepared in embodiment 1;

Fig. 4 is the scanning electron micrograph of the composite microsphere material with wave-absorbing and thermal management dual functions prepared in Example 1;

Fig. 5 is the two-dimensional graph of the electromagnetic wave absorption characteristic of the calcined attapulgite-Ni-Co magnetic particle-carbon nanotube composite microsphere prepared in Example 1;

Fig. 6 is the three-dimensional graph of the electromagnetic wave absorption characteristic of the calcined attapulgite-Ni-Co magnetic particle-carbon nanotube composite microsphere prepared in Example 1;

Fig. 7 is the thermogravimetric analysis curve of the composite microsphere material with wave-absorbing and thermal management dual functions prepared in Example 1;

Figure 8 is a two-dimensional graph of the electromagnetic wave absorption characteristics of the attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres prepared in Example 2;

FIG. 9 is a two-dimensional graph of the electromagnetic wave absorption characteristics of the calcined attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres prepared in Example 3. FIG.

detailed description

The following are specific embodiments of the present invention and in conjunction with the accompanying drawings, the technical solutions of the present invention are further described, but the present invention is not limited to these embodiments.

Example 1

Preparation of Ni-Co magnetic particles:

Weigh 4g of cetyltrimethylammonium bromide, 2.4g of NaOH, 0.32g of cobalt acetate tetrahydrate and 1.2g of nickel acetate tetrahydrate, add them into 40mL ethylene glycol solution, stir for 40min, and ultrasonicate for 40min to obtain a mixed suspension. The suspension was poured into a 100mL polytetrafluoroethylene liner, transferred to a stainless steel reactor, and placed in an oven at 200°C for 8 hours for hydrothermal synthesis. After the reaction, the black powder product was collected, washed with deionized water or absolute ethanol, and dried in an oven at 60°C. Preparation of acid-activated attapulgite:

Weigh 20g of attapulgite raw ore, place it in a beaker filled with 200mL of hydrochloric acid solution with a mass fraction of 4wt.%, place the beaker in a constant temperature water bath at 80°C, stir, ultrasonic, and pickle in water bath for 60min, and filter through suction Wash with deionized water until neutral, dry, grind and sieve through 180 mesh to obtain acid-activated attapulgite.

Construction of acid-activated attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres:

(1) Weigh 1g of acid-activated attapulgite, 2g of Ni-Co magnetic particles, 20g of carbon nanotube slurry with a concentration of 10%, mix with 0.4g of sodium hexametaphosphate and 50mL of deionized water, stir for 40min, and sonicate for 60min to obtain acid Activated attapulgite-Ni-Co magnetic particles-carbon nanotube suspension.

(2) The acid-activated attapulgite-Ni-Co magnetic particles-carbon nanotube suspension is spray-dried. The spray dryer needle setting is 3.0, the fan frequency is set at 35.00Hz, the inlet air temperature is set at 160°C, and the creep speed is 2RPM. Collect dry material.

(3) The dried material collected by spray drying was transferred to a muffle furnace, and calcined at 350° C. for 2 h in an argon atmosphere to obtain attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres. Preparation of composite microsphere materials with dual functions of microwave absorption and thermal management.

Weigh 2g of attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres and 3g of paraffin (P) and transfer to a suction filter bottle, vacuumize at room temperature for 30min, then vacuumize in a water bath at 90°C for 30min, 60 ℃ oven hot filtration for 24 hours, prepared a composite microsphere material with dual functions of microwave absorption and thermal management.

Example 2

Construction of acid-activated attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres:

(1) Weigh 2g of acid-activated attapulgite, 4g of Ni-Co magnetic particles, 20g of carbon nanotube slurry with a concentration of 10%, mix with 0.4g of sodium hexametaphosphate and 50mL of deionized water, stir for 40min, and sonicate for 60min to obtain acid Activated attapulgite-Ni-Co magnetic particles-carbon nanotube suspension.

(2) The acid-activated attapulgite-Ni-Co magnetic particles-carbon nanotube suspension is spray-dried. The spray dryer needle setting is 3.0, the fan frequency is set at 35.00Hz, the inlet air temperature is set at 160°C, and the creep speed is 2RPM. Collect dry material.

(3) The dried material collected by spray drying was transferred to a muffle furnace, and calcined at 350° C. for 2 h in an argon atmosphere to obtain attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres.

Example 3

Construction of acid-activated attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres:

(1) Weigh 1g of acid-activated attapulgite, 2g of Ni-Co magnetic particles, 15g of carbon nanotube slurry with a concentration of 10%, mix with 0.4g of sodium hexametaphosphate and 50mL of deionized water, stir for 40min, and sonicate for 60min to obtain acid Activated attapulgite-Ni-Co magnetic particles-carbon nanotube suspension.

(2) The acid-activated attapulgite-Ni-Co magnetic particles-carbon nanotube suspension is spray-dried. The spray dryer needle setting is 3.0, the fan frequency is set at 35.00Hz, the inlet air temperature is set at 160°C, and the creep speed is 2RPM. Collect dry material.

(3) The dried material collected by spray drying was transferred to a muffle furnace, and calcined at 350° C. for 2 h in an argon atmosphere to obtain attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres. Preparation of composite microsphere materials with dual functions of microwave absorption and thermal management.

Referring to accompanying drawing 1, it is the scanning electron micrograph of the Ni-Co magnetic particle that embodiment 1 prepares. It can be seen that the size of the prepared Ni-Co magnetic particles is about 0.5-1.0 μm. The magnetic particles of this size are beneficial to the subsequent construction of composite microspheres, and the Ni-Co magnetic metal alloy is also a good magnetic loss material, which helps to improve the microwave absorption performance of the composite microspheres.

See accompanying drawing 2, which is a scanning electron micrograph of the composite microspheres prepared by spray-drying the acid-activated attapulgite-Ni-Co magnetic particles-carbon nanotube suspension in Example 1. It can be seen that the size of the constructed composite microspheres is about 5-7 μm, and the composite microspheres have many staggered pores and large specific surface area, which provide a large number of adsorption sites for phase change materials and help to improve the thermal energy storage of composite materials ability.

Referring to accompanying drawing 3, it is the scanning electron micrograph of the attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres calcined in Example 1. It can be seen that the constructed composite microspheres did not collapse after calcination and activation, and still maintained a large number of staggered channels and large specific surface of the composite microspheres, which is helpful for subsequent encapsulation of phase change materials into its rigid structure.

Referring to accompanying drawing 4, it is the scanning electron micrograph of the composite microsphere with dual functions of absorbing and thermal management prepared in Example 1. It can be seen that after the composite microspheres and phase change material paraffin are compounded by vacuum impregnation, a layer of smooth paraffin is coated on the surface of the composite microspheres, and the paraffin is encapsulated in the pores of the composite microspheres to prevent leakage.

Referring to accompanying drawings 5 and 6, it is the electromagnetic wave absorption characteristics of the attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres prepared in Example 1, according to the relative complex dielectric under different given absorber thicknesses Constant and permeability, combined with the transmission line theory, the reflection loss value of the sample is simulated and calculated, and the corresponding two-dimensional curve and three-dimensional surface diagram are drawn. In the range of 2-18GHz, when the thickness of the composite microsphere is only 1.7mm, the effective absorption bandwidth can reach 5.54GHz, and when the thickness is 1.6mm, the maximum reflection loss value is 21.81dB at 15.17GHz. The introduction of attapulgite can adjust the complex dielectric constant of the composite material to an appropriate range to ensure the balance of the impedance matching characteristics of the material. The porous structure of the composite microsphere can cause the incident electromagnetic wave to be reflected and lost multiple times inside the sphere. Combined with the magnetic The strong magnetic loss ability of the metal particles and the synergistic effect of multiple loss mechanisms give the composite material excellent microwave-absorbing properties.

Referring to accompanying drawing 7, it is the thermal gravimetric analysis curve of the composite microsphere material with wave-absorbing and thermal management dual functions prepared in Example 1, the loading capacity of the composite microsphere to paraffin is about 47.8%, which mainly benefits from the composite microsphere The porous structure and large specific surface provide a large number of adsorption sites for paraffin, and the paraffin is encapsulated in its structure, so that the composite material has superior thermal energy storage capacity.

Referring to accompanying drawing 8, it is the electromagnetic wave absorption characteristic of the attapulgite-Ni-Co magnetic particle-carbon nanotube composite microsphere after the calcination prepared in embodiment 2, according to the relative complex permittivity and Permeability, combined with the transmission line theory, the reflection loss value of the sample was calculated by simulation, and the corresponding two-dimensional curve was drawn. In the range of 2-18GHz, when the thickness of the composite microsphere is only 1.7mm, the effective absorption bandwidth can reach 5.02GHz, and when the thickness is 2.5mm, the maximum reflection loss value is 45.94dB at 9.13GHz.

Referring to accompanying drawing 9, it is the electromagnetic wave absorption characteristic of the attapulgite-Ni-Co magnetic particle-carbon nanotube composite microsphere after calcining prepared in embodiment 3, according to the relative complex permittivity and Permeability, combined with the transmission line theory, the reflection loss value of the sample was calculated by simulation, and the corresponding two-dimensional curve was drawn. In the range of 2-18GHz, when the thickness of the composite microsphere is only 1.8mm, the effective absorption bandwidth can reach 5.44GHz, and when the thickness is 2.0mm, the maximum reflection loss value is 36.45dB at 12.32GHz.

What is not involved above is applicable to the prior art.

Although some specific embodiments of the present invention have been described in detail by examples, those skilled in the art should understand that the above examples are only for illustration, rather than for limiting the scope of the present invention. Various modifications or additions or similar substitutions can be made to the described specific embodiments without departing from the direction of the present invention or exceeding the scope defined by the appended claims. Those skilled in the art should understand that any modifications, equivalent replacements, improvements, etc. made to the above implementations based on the technical essence of the present invention shall be included in the protection scope of the present invention.

Claims (10)

1. A preparation method of composite microspheres with dual functions of wave absorption and thermal management, characterized in that: comprising the following steps: S1: Acid-activated attapulgite, Ni-Co magnetic particles, carbon nanotube slurry, sodium hexametaphosphate and water were mixed and stirred, and ultrasonically obtained to obtain an acid-activated attapulgite-Ni-Co magnetic particle-carbon nanotube suspension; S2: Acid-activated attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres were constructed by spray drying the suspension; S3: calcining to obtain attapulgite-Ni-Co magnetic particles-carbon nanotube composite microspheres; S4: Vacuum impregnation of composite microspheres and phase change materials to obtain composite microspheres with dual functions of microwave absorption and thermal management; Wherein, the preparation steps of Ni-Co magnetic particles are as follows; weigh cetyltrimethylammonium bromide, NaOH, cobalt acetate tetrahydrate and nickel acetate tetrahydrate, add them to ethylene glycol solution, stir, and ultrasonically obtain a mixed suspension, The mixed suspension was subjected to hydrothermal synthesis; after the reaction, the black powder product was collected, washed with deionized water or absolute ethanol, and dried. 2. A method for preparing composite microspheres with dual functions of wave absorption and heat management as claimed in claim 1, characterized in that: in the method for preparing Ni-Co magnetic particles, the cetyltrimethyl Ammonium bromide, NaOH, cobalt acetate tetrahydrate, nickel acetate tetrahydrate and ethylene glycol are calculated in parts by weight as follows: Hexadecyltrimethylammonium bromide: 2 to 6 parts NaOH: 1 to 4 parts Cobalt acetate tetrahydrate: 0.2 to 0.5 parts Nickel acetate tetrahydrate: 0.5 to 3 parts Ethylene glycol: 30-50 parts. 3. A method for preparing composite microspheres with dual functions of wave absorption and heat management as claimed in claim 1, characterized in that: in the method for preparing Ni-Co magnetic particles, the stirring speed is 500-1000r/min , the stirring time is 30-60min; the ultrasonic treatment time is 30-60min; the hydrothermal synthesis temperature is 180-200°C, and the hydrothermal synthesis time is 6-12h. 4. A method for preparing composite microspheres with dual functions of wave absorption and heat management as claimed in claim 1, characterized in that: the attapulgite raw ore is soaked in acid solution to obtain acid-activated attapulgite, and the acid activation process It is: soaking in acid solution, solid-liquid separation, washing, and drying; the acid solution is an aqueous solution of strong inorganic acid with a H ⁺ concentration of 1 to 4 mol/L, and the soaking is carried out while stirring. The temperature is 60~90℃, and the soaking time is 40~120min. 5. A method for preparing composite microspheres with dual functions of wave absorption and heat management as claimed in claim 1, characterized in that: in step S1, the acid-activated attapulgite, Ni-Co magnetic particles, carbon The nanotube slurry and sodium hexametaphosphate and water are in the following parts by weight: Acid-activated attapulgite: 0.5 to 2 parts Ni-Co magnetic particles: 1 to 5 parts Carbon nanotube slurry: 10-30 parts, the concentration of carbon nanotube slurry is 10% Sodium hexametaphosphate: 0.2 to 1 part Water: 30-80 parts. 6. A method for preparing composite microspheres with dual functions of wave absorption and heat management as claimed in claim 1, characterized in that: in step S1, the stirring speed is 600-1000r/min, and the stirring time is 30 ～60min; the ultrasonic treatment time is 40～80min; in step S2, during the spray drying process: the spray dryer needle is set to 3.0, the fan frequency is set to 35.00Hz, the air inlet temperature is set to 150～180℃, and the creeping speed is 1 ~6 RPM. 7. A method for preparing composite microspheres with dual functions of microwave absorption and heat management as claimed in claim 1, characterized in that: in step S3, the calcination temperature is 300-400°C, and the calcination time is 1-400°C. 4h, the calcination atmosphere is an inert gas. 8. A method for preparing composite microspheres with dual functions of wave absorption and heat management as claimed in claim 1, characterized in that: in step S4, the dosage relationship between composite microspheres and phase change materials is: 40-60wt .%: 40-60wt.%; Vacuum impregnation is performed at room temperature for 10-50 minutes, and then at 40-90°C for 10-50 minutes. 9. A composite microsphere with dual functions of microwave absorption and heat management prepared by the preparation method according to any one of claims 1-8. 10. The application of the composite microsphere with dual functions of wave absorption and heat management as claimed in claim 9, characterized in that it is used for electromagnetic interference shielding and thermal energy regulation of high-end electronic equipment.

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