阅读说明：本技术 一种应用于5g毫米波段的复合吸波材料及其制备方法 (Composite wave-absorbing material applied to 5G millimeter wave band and preparation method thereof ) 是由 曾强 陈炜 于 2019-10-01 设计创作，主要内容包括：本发明公开了一种应用于5G毫米波段的复合吸波材料的制备方法,其特征在于,包括如下步骤：步骤S1、基于二茂铁磺酸基席夫碱缩聚物的制备,步骤S2、基于噻吩席夫碱缩聚物的制备,步骤S3、石墨烯掺杂Fe-Gd-Sr-Zr-O的制备,步骤S4、石墨烯掺杂Fe-Gd-Sr-Zr-O的表面修饰,步骤S5、烯丙基-β-环糊精/4,4’-二氰基二苯乙烯/乙烯基二甲基氟硅烷共聚物的制备,步骤S6、复合吸波材料的制备。本发明还公开了根据所述应用于5G毫米波段的复合吸波材料的制备方法制备而成的应用于5G毫米波段的复合吸波材料。本发明公开的应用于5G毫米波段的复合吸波材料吸收频段宽、吸收率高,抗氧化性、耐腐蚀性、性能稳定性和机械力学性能优异,使用寿命长。(The invention discloses a preparation method of a composite wave-absorbing material applied to a 5G millimeter wave band, which is characterized by comprising the following steps of: s1, preparing a ferrocene sulfonic acid group-based Schiff base polycondensate, S2, preparing a thiophene Schiff base polycondensate, S3, preparing graphene doped Fe-Gd-Sr-Zr-O, S4, modifying the surface of the graphene doped Fe-Gd-Sr-Zr-O, S5, preparing an allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluoro silane copolymer, and S6, and preparing a composite wave-absorbing material. The invention also discloses the composite wave-absorbing material applied to the 5G millimeter wave band, which is prepared by the preparation method of the composite wave-absorbing material applied to the 5G millimeter wave band. The composite wave-absorbing material applied to the 5G millimeter wave band disclosed by the invention has the advantages of wide absorption frequency band, high absorption rate, excellent oxidation resistance, corrosion resistance, performance stability, mechanical property and long service life.)

1. A preparation method of a composite wave-absorbing material applied to a 5G millimeter wave band is characterized by comprising the following steps:

step S1, preparing the condensation polymer based on the ferrocene sulfonic acid Schiff base: adding 1,1' -ferrocene dicarboxaldehyde and 2, 5-diaminobenzene sulfonic acid into an organic solvent, stirring and reacting for 4-6 hours at 85-95 ℃ under the atmosphere of nitrogen or inert gas, cooling to room temperature after the reaction is finished, removing the solvent by rotary evaporation, washing for 3-6 times by using petroleum ether, and then placing in a vacuum drying oven for drying at 50-70 ℃ to constant weight to obtain a Schiff base polycondensate based on ferrocene sulfonic acid group;

step S2, preparation of thiophene schiff base based polycondensate: adding 2, 5-thiophenedicarboxaldehyde and 2, 3-diaminonaphthalene into ethanol, stirring and reacting for 6-8 hours at 80-90 ℃ in a nitrogen atmosphere, cooling to room temperature after the reaction is finished, removing the solvent by rotary evaporation, washing for 3-6 times by using petroleum ether, and drying in a vacuum drying oven at 60-80 ℃ to constant weight to obtain a condensation polymer based on thiophene Schiff base;

step S3, preparing graphene doped Fe-Gd-Sr-Zr-O: adding ferric salt, gadolinium salt, strontium salt and zirconium salt into a beaker containing ethanol, stirring for 0.5-1h, slowly adding sodium acetate, stirring vigorously for 2-3h, transferring the solution into a hydrothermal reaction kettle with a polyvinyl fluoride lining, and reacting for 15-20h at the temperature of 210 ℃ under 180-; taking out the reaction kettle, repeatedly washing the reaction system with deionized water and absolute ethyl alcohol after the reaction system is cooled, and finally drying the reaction system in a vacuum drying oven at the temperature of 70-80 ℃ for 18-24 hours; then sintering the mixture for 2 to 4 hours at the temperature of 600 ℃ and 700 ℃, and naturally cooling the mixture to room temperature to obtain Fe-Gd-Sr-Zr-O; then mixing and grinding the obtained Fe-Gd-Sr-Zr-O and graphene for 20-40 minutes, heating to 550-600 ℃ at the heating rate of 5-10 ℃/min in the nitrogen atmosphere, preserving the heat for 6-8 hours, naturally cooling, crushing, and sieving with a sieve of 300 meshes and 400 meshes to obtain the graphene doped Fe-Gd-Sr-Zr-O;

s4, surface modification of graphene doped Fe-Gd-Sr-Zr-O: dispersing the graphene doped Fe-Gd-Sr-Zr-O prepared in the step S3 in ethanol, adding 3-triethoxysilylpropyltrimethylammonium chloride, stirring and reacting at 60-80 ℃ for 3-5 hours, and then performing rotary evaporation to remove ethanol to obtain the surface modified graphene doped Fe-Gd-Sr-Zr-O;

step S5, preparation of allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluoro silane copolymer: adding allyl-beta-cyclodextrin, 4 '-dicyanodistyrene, vinyl dimethyl fluorosilane and an initiator into a high boiling point solvent, stirring and reacting for 3-5 hours at 70-80 ℃ in a nitrogen atmosphere, then precipitating in water, washing the precipitated polymer for 3-6 times by using ethanol, and then placing in a vacuum drying oven for drying at 80-90 ℃ to constant weight to obtain an allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluorosilane copolymer;

step S6, preparation of the composite wave-absorbing material: adding the ferrocene sulfonic group-based Schiff base polycondensate prepared in the step S1, the thiophene Schiff base polycondensate prepared in the step S2, the surface modified graphene doped Fe-Gd-Sr-Zr-O prepared in the step S4, the allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluoro silane copolymer prepared in the step S5 and phosphorus pentoxide into a high-speed mixer, dispersing for 15-30 minutes at a high speed to obtain a mixture, and then melting, blending and extruding the mixture at the temperature of 190 and 230 ℃ by a double-screw extruder to obtain the composite wave-absorbing material.

2. The preparation method of the composite wave-absorbing material applied to the 5G millimeter wave band according to claim 1, wherein the mass ratio of the 1,1' -ferrocene dicarboxaldehyde, the 2, 5-diaminobenzene sulfonic acid and the organic solvent in the step S1 is 1.29:1 (7-12).

3. The method for preparing the composite wave-absorbing material applied to the 5G millimeter wave band according to claim 1, wherein the organic solvent is one of ethanol, isopropanol, toluene and tetrahydrofuran; the inert gas is one of helium, neon and argon.

4. The method for preparing the composite wave-absorbing material applied to the 5G millimeter wave band according to claim 1, wherein the mass ratio of the 2, 5-thiophenedicarboxaldehyde, the 2, 3-diaminonaphthalene and the ethanol in the step S2 is 1:1.13 (7-10).

5. The preparation method of the composite wave-absorbing material applied to the 5G millimeter wave band according to claim 1, wherein the mass ratio of the iron salt, the gadolinium salt, the strontium salt, the zirconium salt, the ethanol, the sodium acetate and the graphene in the step S3 is 1:0.05:0.1:0.1 (20-30: 3) (0.01-0.03).

6. The method for preparing the composite wave-absorbing material applied to the 5G millimeter wave band according to claim 1, wherein the ferric salt is at least one of ferric chloride, ferric nitrate and ferric sulfate; the gadolinium salt is at least one of gadolinium chloride, gadolinium nitrate and gadolinium sulfate; the strontium salt is at least one of strontium chloride, strontium nitrate and strontium sulfate; the zirconium salt is at least one of zirconium chloride, zirconium nitrate and zirconium sulfate.

7. The preparation method of the composite wave-absorbing material applied to the 5G millimeter wave band according to claim 1, wherein the mass ratio of the graphene doped Fe-Gd-Sr-Zr-O, the ethanol and the 3-triethoxysilylpropyltrimethylammonium chloride in the step S4 is 1 (5-10) to (0.1-0.3).

8. The method for preparing the composite wave-absorbing material applied to the 5G millimeter wave band according to claim 1, wherein the mass ratio of the allyl-beta-cyclodextrin, the 4,4' -dicyanodistyrene, the vinyl dimethyl fluorosilane, the initiator and the high boiling point solvent in the step S5 is 0.2:1:0.3 (0.01-0.03): 5-8); the initiator is at least one of azobisisobutyronitrile and azobisisoheptonitrile; the high boiling point solvent is at least one of dimethyl sulfoxide, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone.

9. The preparation method of the composite wave-absorbing material applied to the 5G millimeter waveband of claim 1 is characterized in that in the step S6, the mass ratio of the ferrocene sulfonic acid group-based Schiff base polycondensate, the thiophene Schiff base polycondensate, the surface modified graphene-doped Fe-Gd-Sr-Zr-O, the allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluoro silane copolymer and the phosphorus pentoxide is 0.5:0.3:0.4 (3-5): 0.05.

10. The composite wave-absorbing material applied to the 5G millimeter wave band, which is prepared by the preparation method of the composite wave-absorbing material applied to the 5G millimeter wave band according to any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of wave-absorbing materials, in particular to a composite wave-absorbing material applied to a 5G millimeter wave band and a preparation method thereof.

Background

With the continuous progress of science and technology, electronic instruments and wireless communication technology are also rapidly developed. With the issuance of the low-frequency test frequency license of the 5G system in China, the fifth generation mobile communication technology (5G) era has been marked in China. The 5G communication transmission speed is ultra-fast, can let people share the dream of 3D film, game and super high quality image quality program with intelligent terminal and realize, can provide more convenience in life for people, however, the electromagnetic pollution brought by it is also not a little worth, the excessive electromagnetic wave radiation brought by 5G communication technology can induce pathological changes such as nervous system, immune system, reproductive system and blood circulation system, even serious diseases including cancer, be in the electromagnetic wave environment for a long time, the injury of the tissue and organ that are damaged by the electromagnetic wave and do not reach self-repairing in the human body can become functional pathological changes because of long-term accumulation, can endanger life when serious. Meanwhile, the normal operation of some electronic devices is also affected. Therefore, the electromagnetic pollution caused by the 5G communication is not beneficial to the further development of the 5G communication technology.

An electromagnetic wave absorbing material, a wave absorbing material for short, is a composite functional material which can absorb most of the electromagnetic waves projected on the surface of the material, convert electromagnetic energy into heat energy or other forms of energy through the electric or magnetic loss of the material and consume the heat energy, and has very small reflection, scattering and transmission. Since the 5G application band is the millimeter wave band, the application of the millimeter wave band will also promote miniaturization of various electronic components. The updating of related equipment materials will certainly put great demands on the wave-absorbing materials capable of being applied to the 5G millimeter wave band, so the research of the wave-absorbing materials in the frequency band is particularly important at the present stage.

The traditional wave-absorbing materials can be divided into a resistance type, a dielectric type and a magnetic medium type according to the wave-absorbing principle; the common resistance type wave-absorbing material mainly comprises carbon fiber, silicon carbide fiber, conductive graphite powder, conductive high polymer and the like; metal short fiber, barium titanate ceramic and the like belong to dielectric medium type wave-absorbing materials; ferrite, carbonyl iron powder, superfine metal powder and the like belong to magnetic medium type wave-absorbing materials. The wave-absorbing materials can not change the wave frequency absorption width and the fixed absorption peak position, and the effective wave-absorbing frequency band of the wave-absorbing materials is narrow, and the wave-absorbing performance is not ideal.

Therefore, the new wave-absorbing material applied to the 5G millimeter wave band is developed, is necessary for improving the performance of the existing wave-absorbing material and the practical application and production, and has very important significance for promoting the development of the 5G communication technology.

Disclosure of Invention

The invention aims to solve the problems and provides a composite wave-absorbing material applied to a 5G millimeter wave band and a preparation method thereof, wherein the preparation method is simple and easy to implement, controllable in process, low in cost, convenient for industrial continuous production, and high in production efficiency and finished product qualification rate; the prepared composite wave-absorbing material applied to the 5G millimeter wave band has the advantages of wide absorption frequency band, high absorption rate, excellent oxidation resistance, corrosion resistance, performance stability, mechanical property and long service life.

In order to achieve the purpose, the invention adopts the technical scheme that:

a preparation method of a composite wave-absorbing material applied to a 5G millimeter wave band is characterized by comprising the following steps:

step S1, preparing the condensation polymer based on the ferrocene sulfonic acid Schiff base: adding 1,1' -ferrocene dicarboxaldehyde and 2, 5-diaminobenzene sulfonic acid into an organic solvent, stirring and reacting for 4-6 hours at 85-95 ℃ under the atmosphere of nitrogen or inert gas, cooling to room temperature after the reaction is finished, removing the solvent by rotary evaporation, washing for 3-6 times by using petroleum ether, and then placing in a vacuum drying oven for drying at 50-70 ℃ to constant weight to obtain a Schiff base polycondensate based on ferrocene sulfonic acid group;

step S2, preparation of thiophene schiff base based polycondensate: adding 2, 5-thiophenedicarboxaldehyde and 2, 3-diaminonaphthalene into ethanol, stirring and reacting for 6-8 hours at 80-90 ℃ in a nitrogen atmosphere, cooling to room temperature after the reaction is finished, removing the solvent by rotary evaporation, washing for 3-6 times by using petroleum ether, and drying in a vacuum drying oven at 60-80 ℃ to constant weight to obtain a condensation polymer based on thiophene Schiff base;

step S3, preparing graphene doped Fe-Gd-Sr-Zr-O: adding ferric salt, gadolinium salt, strontium salt and zirconium salt into a beaker containing ethanol, stirring for 0.5-1h, slowly adding sodium acetate, stirring vigorously for 2-3h, transferring the solution into a hydrothermal reaction kettle with a polyvinyl fluoride lining, and reacting for 15-20h at the temperature of 210 ℃ under 180-; taking out the reaction kettle, repeatedly washing the reaction system with deionized water and absolute ethyl alcohol after the reaction system is cooled, and finally drying the reaction system in a vacuum drying oven at the temperature of 70-80 ℃ for 18-24 hours; then sintering the mixture for 2 to 4 hours at the temperature of 600 ℃ and 700 ℃, and naturally cooling the mixture to room temperature to obtain Fe-Gd-Sr-Zr-O; then mixing and grinding the obtained Fe-Gd-Sr-Zr-O and graphene for 20-40 minutes, heating to 550-600 ℃ at the heating rate of 5-10 ℃/min in the nitrogen atmosphere, preserving the heat for 6-8 hours, naturally cooling, crushing, and sieving with a sieve of 300 meshes and 400 meshes to obtain the graphene doped Fe-Gd-Sr-Zr-O;

s4, surface modification of graphene doped Fe-Gd-Sr-Zr-O: dispersing the graphene doped Fe-Gd-Sr-Zr-O prepared in the step S3 in ethanol, adding 3-triethoxysilylpropyltrimethylammonium chloride, stirring and reacting at 60-80 ℃ for 3-5 hours, and then performing rotary evaporation to remove ethanol to obtain the surface modified graphene doped Fe-Gd-Sr-Zr-O;

step S5, preparation of allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluoro silane copolymer: adding allyl-beta-cyclodextrin, 4 '-dicyanodistyrene, vinyl dimethyl fluorosilane and an initiator into a high boiling point solvent, stirring and reacting for 3-5 hours at 70-80 ℃ in a nitrogen atmosphere, then precipitating in water, washing the precipitated polymer for 3-6 times by using ethanol, and then placing in a vacuum drying oven for drying at 80-90 ℃ to constant weight to obtain an allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluorosilane copolymer;

step S6, preparation of the composite wave-absorbing material: adding the ferrocene sulfonic group-based Schiff base polycondensate prepared in the step S1, the thiophene Schiff base polycondensate prepared in the step S2, the surface modified graphene doped Fe-Gd-Sr-Zr-O prepared in the step S4, the allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluoro silane copolymer prepared in the step S5 and phosphorus pentoxide into a high-speed mixer, dispersing for 15-30 minutes at a high speed to obtain a mixture, and then melting, blending and extruding the mixture at the temperature of 190 and 230 ℃ by a double-screw extruder to obtain the composite wave-absorbing material.

Further, the mass ratio of the 1,1' -ferrocene dicarboxaldehyde, the 2, 5-diaminobenzene sulfonic acid and the organic solvent in the step S1 is 1.29:1 (7-12).

Further, the organic solvent is one of ethanol, isopropanol, toluene and tetrahydrofuran; the inert gas is one of helium, neon and argon.

Furthermore, the mass ratio of the 2, 5-thiophenedicarboxaldehyde, the 2, 3-diaminonaphthalene and the ethanol in the step S2 is 1:1.13 (7-10).

Further, in the step S3, the mass ratio of the iron salt, the gadolinium salt, the strontium salt, the zirconium salt, the ethanol, the sodium acetate, and the graphene is 1:0.05:0.1:0.1 (20-30: 3) (0.01-0.03).

Further, the iron salt is at least one of ferric chloride, ferric nitrate and ferric sulfate; the gadolinium salt is at least one of gadolinium chloride, gadolinium nitrate and gadolinium sulfate; the strontium salt is at least one of strontium chloride, strontium nitrate and strontium sulfate; the zirconium salt is at least one of zirconium chloride, zirconium nitrate and zirconium sulfate.

Further, in the step S4, the mass ratio of the graphene doped Fe-Gd-Sr-Zr-O, the ethanol and the 3-triethoxysilylpropyltrimethylammonium chloride is 1 (5-10) to 0.1-0.3.

Further, in step S5, the mass ratio of the allyl- β -cyclodextrin, the 4,4' -dicyanodistyrene, the vinyl dimethyl fluorosilane, the initiator, and the high boiling point solvent is 0.2:1:0.3 (0.01-0.03): 5-8.

Preferably, the initiator is at least one of azobisisobutyronitrile and azobisisoheptonitrile; the high boiling point solvent is at least one of dimethyl sulfoxide, N-dimethylformamide, N-dimethylacetamide and N-methylpyrrolidone.

Further, in the step S6, the mass ratio of the ferrocene sulfonic acid group-based Schiff base polycondensate, the thiophene Schiff base polycondensate, the surface-modified graphene-doped Fe-Gd-Sr-Zr-O, the allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluoro silane copolymer and the phosphorus pentoxide is 0.5:0.3:0.4 (3-5) to 0.05.

The invention also aims to provide the composite wave-absorbing material applied to the 5G millimeter wave band, which is prepared by the preparation method of the composite wave-absorbing material applied to the 5G millimeter wave band.

Adopt the produced beneficial effect of above-mentioned technical scheme to lie in:

(1) the preparation method of the composite wave-absorbing material applied to the 5G millimeter wave band, provided by the invention, has the advantages of simple and feasible process, controllable process, low cost, convenience for industrial continuous production and high production efficiency and finished product qualification rate.

(2) The composite wave-absorbing material applied to the 5G millimeter wave band overcomes the defects that the traditional wave-absorbing material can not change the wave frequency absorption width and the fixed absorption peak position, the effective wave-absorbing frequency band of the wave-absorbing material is narrow, the wave-absorbing performance is not ideal, the wave-absorbing material is not suitable for the use requirement of the 5G millimeter wave band, and the oxidation resistance, the corrosion resistance, the performance stability and the mechanical property need to be further improved, and has the advantages of wide absorption frequency band, high absorption rate, excellent oxidation resistance, corrosion resistance, performance stability and mechanical property and long service life.

(3) The composite wave-absorbing material applied to the 5G millimeter wave band is mainly prepared by mixing a ferrocene sulfonic acid group-based Schiff base polycondensate, a thiophene Schiff base polycondensate and surface-modified graphene-doped Fe-Gd-Sr-Zr-O and allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluoro silane copolymer, combines the advantages of Schiff base substances, a resistance type wave-absorbing material, a dielectric type wave-absorbing material and a magnetic medium type wave-absorbing material, gives consideration to the electric loss and the magnetic loss of the material, and has the synergistic effect of multiple loss mechanisms, so that the reflection loss of the material in the millimeter wave band is large, and the final absorption performance is excellent.

(4) According to the composite wave-absorbing material applied to the 5G millimeter wave band, the Schiff base is prepared into the polycondensate, so that the polycondensate is easier to form with other components, and the wave-absorbing performance of the polycondensate can be effectively improved; part of sulfonic groups on the basis of the ferrocene sulfonic acid group Schiff base polycondensate are easy to generate cross-linking reaction with benzene rings on the basis of the thiophene Schiff base polycondensate and the allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluoro silane copolymer under the action of phosphorus pentoxide serving as a catalyst in the material forming stage, so that each polymer component forms an organic whole, and the comprehensive performance of the material is improved; due to the introduction of the surface modified graphene doped with Fe-Gd-Sr-Zr-O, the surface modification introduces a quaternary ammonium salt cation structure, so that on one hand, the dispersibility and the compatibility with other components are improved, on the other hand, the quaternary ammonium salt cation and another part of sulfonic acid groups on the ferrocene sulfonic acid group Schiff base polycondensate are subjected to ion exchange reaction, so that all structures in the material are tightly connected in a chemical bond form to form a three-dimensional network structure, the comprehensive performance of the material is further improved, the performance stability of the material is better, and the service life is longer.

(5) According to the composite wave-absorbing material applied to the 5G millimeter wave band, the surface modified graphene is doped with Fe-Gd-Sr-Zr-O, the dielectric medium performance and the magnetic medium performance are better through the doping of heterogeneous elements, the synergistic effect is further facilitated through the doping of the graphene, and the wave-absorbing effect is improved; in addition, ferrocenyl on the basis of the ferrocene sulfo-group Schiff base condensation polymer is easy to have an envelope subject-object interaction with cyclodextrin on the basis of the thiophene Schiff base condensation polymer and the allyl-beta-cyclodextrin/4, 4' -dicyanodistyrene/vinyl dimethyl fluoro silane copolymer in the material forming stage, and the introduction of fluorine silicon and cyano structures can improve the weather resistance of the material, and is finally beneficial to the improvement of comprehensive performance, the improvement of wave absorbing effect and the extension of service life.

Detailed Description

In order to make the technical solutions of the present invention better understood and make the above features, objects, and advantages of the present invention more comprehensible, the present invention is further described with reference to the following examples. The examples are intended to illustrate the invention only and are not intended to limit the scope of the invention.

The allyl-beta-cyclodextrin involved in the following examples of the invention was obtained from Zhiyuan Biotech, Inc., Shandong, Bingzhou; other raw materials were all purchased commercially.