Thiophene conjugated microporous polymer wave-absorbing material and preparation method thereof

Abstract

The application provides a novel thiophene conjugated microporous polymer wave-absorbing material and a preparation method thereof, the wave-absorbing material is composed of a conjugated microporous polymer and a polypyrrole, the conjugated microporous polymer is formed by coupling polymerization of dibromothiophene monomers and borate monomers under the action of a palladium catalyst, and the polypyrrole is obtained by confined polymerization of the polypyrrole in the micropores of the conjugated microporous polymer, and has a reticular structure. The application introduces aromatic heterocyclic molecules on the conjugated microporous molecular skeleton, synthesizes a conjugated microporous polymer containing a thiophene group, introduces the polypyrrole into the nanopores of the conjugated microporous polymer by a confined polymerization method, prepares a novel thiophene conjugated microporous polymer, and then adjusts the ratio of the polypyrrole and the conjugated microporous polymer to obtain a novel conjugated microporous polymer wave-absorbing material with excellent electromagnetic wave-absorbing performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wave-absorbing materials, in particular to a novel thienyl conjugated microporous polymer wave-absorbing material and a preparation method thereof. BACKGROUND

[0002] With the rapid development of electronic technology, electromagnetic radiation has gradually entered people's daily life. These electromagnetic radiations not only interfere with the normal work of various instruments, but also seriously harm human health. Therefore, in order to eliminate electromagnetic radiation, various wave-absorbing materials have been developed, such as magnetic materials, carbon materials, ceramics, metal oxides / sulfides and conductive polymers. According to the different electromagnetic loss mechanisms, wave-absorbing materials can be divided into two categories: magnetic loss materials and dielectric loss materials. The magnetic loss materials are generally magnetic metal oxides or alloys such as ferrite, carbonyl iron powder, carbonyl nickel powder, cobalt-nickel alloy, etc. The dielectric loss type wave-absorbing material is generally a composite material composed of high-conductivity carbon nanometer particles, dielectric ceramic nanometer particles and metal semiconductor oxides, which forms various mixed nanostructures. Compared with traditional inorganic wave-absorbing materials such as ferrite or ceramic, metal oxide, etc., organic wave-absorbing materials have good chemical stability, low density and are easy to functionalize, so they have unique advantages in the field of wave-absorbing. However, most organic materials have poor electrical conductivity and cannot be used as electromagnetic wave absorbing materials with excellent performance. Therefore, effectively enhancing the electrical conductivity of organic wave-absorbing materials is the key to improving the wave-absorbing performance of such materials.

[0003] Conjugated microporous polymers are a kind of reticular porous polymers with π-conjugated system structure. Such materials have high specific surface area, permanent porosity, good stability and easy chemical modification. As a kind of multifunctional porous material, conjugated microporous polymers have good potential application value in many fields. Conductive polymers have adjustable electrical conductivity, small density, good thermal stability and environmental stability, and have been widely used in antibacterial, anticorrosion, temperature sensing, optoelectronic materials, energy storage, drug release and electromagnetic shielding and many other fields. As a kind of high-performance dielectric loss material, polypyrrole has high mass density and good flexibility, and its morphology is easy to control (such as polypyrrole nanotubes, or spherical, or bowl-shaped structure), so it is considered to be one of the most promising electromagnetic wave absorbers. Introducing polypyrrole into the pores of conjugated microporous polymers, controlling the pore size of the porous material by chemical synthesis, and the micro interaction between polypyrrole and polypyrrole, and then developing a composite material with excellent wave-absorbing performance, is the research hotspot in this field at present.

[0004] Generally, magnetic loss type wave-absorbing materials have high impedance matching and good magnetic loss capacity, and thus have good wave-absorbing performance. However, the magnetic wave-absorbing materials have large density and need to be filled in a coating in a large amount to achieve good wave-absorbing performance. In addition, the magnetic metals and alloys have poor chemical stability and are easy to corrode in a humid environment, resulting in short service life. In contrast to the magnetic loss type wave-absorbing materials, carbon-based wave-absorbing materials have light weight and good chemical stability. In addition, the carbon-based materials have strong designability of microstructure, such as zero-dimensional carbon quantum dots, two-dimensional graphene, three-dimensional carbon nanotubes and other multiple morphologies. Therefore, the carbon-based wave-absorbing materials have attracted extensive attention.

[0005] Zeng et al. connected many super-small Fe3O4 particles to carbon nanotubes (CNTs) and made Fe3O4 aggregate to form microspheres, forming a sea urchin-like structure on the CNTs. The obtained composite material Fe3O4 / CNTs exhibits strong dielectric loss, and when the sample thickness is 2.15 mm and the filling amount is only 5wt%, the reflection loss at 11.12 GHz reaches -56.8 dB. Zhang et al. grew carbon nanotubes on the surface of graphene sheets using dicyanediamine as raw material. Due to the high conductivity of graphene sheets and carbon nanotubes, and the sufficient defects and interfaces between graphene sheets and carbon nanotubes, and the unique three-dimensional structure, the absorption peak width (EAB) can reach 4.63 GHz when the thickness is 1.6 mm, and the maximum absorption peak reaches -44.23 dB at 2.0 mm. Ren et al. used agaric as carbon source and template to prepare Fe3O4 / nitrogenous porous carbon, and combined with freeze-drying pore-forming to realize the three-dimensional conductive network of porous carbon in one sample. Due to the interface polarization of the composite material and the magnetism of Fe3O4, the minimum reflection loss reaches -77.91 dB, and the EAB reaches 8.49 GHz.

[0006] The porous structure of the conjugated microporous polymer helps to construct a wave-absorbing material with good performance. Liao Yaizu et al. anchored metal particles in the microporous channels of CMP (CN117842944A) to achieve uniform dispersion of metal particles, and controlled the electromagnetic parameters and optimized the impedance matching of the wave-absorbing material by adjusting the content of single metal, double metal and metal type. When the filling ratio of the wave-absorbing material is 30wt% and the thickness is 3.0mm, the minimum reflection loss of the wave-absorbing material reaches -49.7dB, and the effective absorption bandwidth is 5.8GHz in the frequency range of 11.8-17.6GHz. Xie Zhipeng et al. first synthesized a conjugated microporous polymer (CN116003116B), and then prepared a hypercrosslinked conjugated microporous polymer through a Friedel-Crafts reaction. Then, the precursor for synthesizing ZnFe2O4 nanoparticles was subjected to hydrothermal reaction, and finally carbonization was carried out at a target temperature to obtain a composite wave-absorbing material. By utilizing the porous characteristics and tubular structure of the polymer, the maximum effective absorption bandwidth can reach 6.24GHz, and the maximum absorption reaches -59.56dB.

[0007] Poly pyrrole also has the ability to prepare good wave-absorbing performance due to the characteristics of conductive and light weight. Ritwik Panigrahi et al. prepared hollow poly pyrrole and its silver nano composite material by using polystyrene (PS) as a template. Liu et al. prepared CoS@PPy microspheres with core-shell structure by solvothermal and self-assembly polymerization. By successfully coating amorphous structure poly pyrrole on CoS microspheres, the maximum reflection loss of CoS@PPy composite material is-41.8 dB, the maximum bandwidth is 5.4 GHz, and the thickness is only 2.05 mm. Feng et al. first synthesized cellulose gel, and then generated poly pyrrole in situ. The composite material shows the best microwave absorbing performance when the compression ratio is 65%, and the minimum reflection loss value is-12.24 dB at 8.53 GHz, and the thickness is 5 mm. In addition, the effective bandwidth can cover the entire X band (8.2-12.4 GHz) by changing the thickness of the composite material in the range of 4-5 mm.

[0008] The prior art with publication number CN 112794994 A discloses a porous organic polymer based on thiophene units and a preparation method and application thereof. A new sulfur-containing porous organic polymer is effectively synthesized by one-pot Suzuki coupling reaction with sulfur-containing thiophene monomer and tris(4-boronic acid pinacol ester phenyl) amine as structural units; the thiophene polymer in the prior art is applied in the field of adsorbing and separating heavy metal mercury ions; in recent years, there are relatively few reports on the synthesis of new porous conjugated polymers containing thiophene units, which limits the further application of porous conjugated polymers containing thiophene units. SUMMARY

[0009] The purpose of the present application is to provide a new thiophene conjugated microporous polymer wave-absorbing material and a preparation method thereof, in order to solve the problem that there are relatively few reports on the synthesis of new porous conjugated polymers containing thiophene units in the prior art, which limits the further application of porous conjugated polymers containing thiophene units.

[0010] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0011] A new thiophene conjugated microporous polymer wave-absorbing material, the wave-absorbing material is composed of a conjugated microporous polymer and a poly pyrrole, the conjugated microporous polymer is formed by coupling polymerization reaction of a dibromothiophene monomer and a borate monomer under the action of a palladium catalyst, and the limited polymerization of the poly pyrrole in the pores of the conjugated microporous polymer obtains a poly pyrrole with a reticular structure.

[0012] The present application introduces a thienyl unit to obtain a novel thienyl D-A type conjugated microporous polymer material, wherein the introduction of D(boronic acid ester monomer)-A(dibromothiophene monomer) structure not only effectively improves the molecular planarity of the conjugated microporous molecular skeleton, but also effectively enhances the outer electron transfer ability through the ICT(intramolecular charge transfer) effect, regulates the HOMO / LUMO energy level and the intrinsic conductive properties of the microporous polymer, further optimizes the interaction with polypyrrole, and finally effectively improves the wave absorption properties of the composite material through the above synergistic effect, and develops a conjugated microporous polymer-polypyrrole composite wave absorption material with excellent wave absorption properties.

[0013] Further, the structure of the conjugated microporous polymer is shown as I:

[0014]

[0015] A preparation method of the wave absorption material as described above, comprising the following steps:

[0016] (1) preparing a conjugated microporous polymer

[0017] The dibromothiophene monomer, boronic acid ester monomer, catalyst, and potassium carbonate are added to a two-neck flask, subjected to anaerobic treatment, then organic solvent and water are added to the flask, and the mixture is stirred and heated to 150 DEG C for 72 hours. After the reaction is completed, the conjugated microporous polymer is obtained by purification.

[0018] The reaction formula for preparing the conjugated microporous polymer is shown as formula IV:

[0019]

[0020]

[0021] (2) preparing a wave absorption material

[0022] The conjugated microporous polymer and pyrrole monomer are added to a single-neck flask, then ferric chloride solution is added to the flask, and the mixture is stirred and reacted at room temperature for 4-5 hours. After purification, the wave absorption material is obtained.

[0023] Further, the molar ratio of the dibromothiophene monomer to the boronic acid ester monomer is 3:2.

[0024] Further, the dibromothiophene monomer is 2,5-dibromothiophene.

[0025] Further, the boronic acid ester monomer is 1,3,5-tris(4-phenylboronic pinacol ester) benzene.

[0026] Further, the palladium catalyst is one of tetrakis(triphenylphosphine)palladium and [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium.

[0027] Further, the mass ratio of the conjugated microporous polymer to the pyrrole monomer is 1:(1-10).

[0028] Further, the concentration of the ferric trichloride solution is 1 mol·L -1 .

[0029] Further, the volume ratio of the organic solvent to water is 27:5.

[0030] Further, the carbonate salt is one of potassium carbonate and cesium carbonate.

[0031] Further, the molar ratio of the catalyst to the dibromothiophene monomer is 1:125.

[0032] Further, the molar ratio of the carbonate salt to the dibromothiophene monomer is 4:1.

[0033] Further, the purification in step (1) comprises the following steps: after the reaction is completed and the system is cooled to room temperature, the system is washed with water and methanol, then the system is subjected to a cyclopentyl methyl ether soxhlet extraction for 3 days, and then the system is vacuum dried at a drying temperature of 100 DEG C for 12 h.

[0034] Compared with the prior art, the novel thiophene-based conjugated microporous polymer wave-absorbing material and the preparation method thereof have the following advantages:

[0035] 1) The thiophene unit is introduced in the present application to obtain a novel thiophene-based D-A type conjugated microporous polymer material, wherein the introduction of the D (dibromothiophene monomer)-A (borate monomer) structure not only effectively improves the molecular planarity of the conjugated microporous molecular skeleton, but also effectively enhances the outer electron transfer ability through the ICT (intramolecular charge transfer) effect, adjusts the HOMO / LUMO energy level and the intrinsic conductive properties of the microporous polymer, further optimizes the interaction with the polypyrrole, and finally effectively improves the wave-absorbing properties of the composite material through the above synergistic effect, and a conjugated microporous polymer-polypyrrole composite wave-absorbing material with excellent wave-absorbing properties is developed.

[0036] 2) The preparation method of the wave-absorbing material is simple, easy to operate, and has a preparation time period, and can be widely used in a large area. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 The preparation flowchart of the conjugated microporous polymer CMP-TH of Example 1 and Example 2 of the present application is shown in the figure.

[0038] Figure 2 The preparation flowchart of the wave-absorbing material CMP-TH / PPy of Example 3 and Example 4 of the present application is shown in the figure.

[0039] Figure 3Structure diagram of preparing wave-absorbing material from conjugated microporous polymer and polypyrrole of embodiment 3 and embodiment 4 of the present application;

[0040] Figure 4 Scanning electron microscope image of conjugated microporous polymer of embodiment 1 of the present application;

[0041] Figure 5 Solid-state nuclear magnetic resonance image of conjugated microporous polymer CMP-TH of embodiment 1 of the present application;

[0042] Figure 6 X-ray photoelectron spectroscopy image of conjugated microporous polymer of embodiment 1 of the present application;

[0043] Figure 7 Scanning electron microscope image of wave-absorbing material CMP-TH / PPy of embodiment 4 of the present application;

[0044] Figure 8 Infrared spectroscopy image of wave-absorbing material of embodiment 4 of the present application;

[0045] Figure 9 Electromagnetic performance test image of reflection loss of CMP-TH / PPy 1:3 of embodiment 3 of the present application at different thicknesses;

[0046] Figure 10 Electromagnetic performance test image of reflection loss of CMP-TH / PPy 1:5 of embodiment 4 of the present application at different thicknesses;

[0047] Figure 11 Electromagnetic performance test image of reflection loss of PPy of comparative example 1 of the present application at different thicknesses;

[0048] Figure 12 Electromagnetic performance test image of reflection loss of embodiment 3 (CMP-TH / PPy 1:3) of the present application at the same thickness (4.30 mm);

[0049] Figure 13 Electromagnetic performance test image of reflection loss of embodiment 4 (CMP-TH / PPy 1:5) of the present application at the same thickness (2.04 mm). DETAILED DESCRIPTION

[0050] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0051] The application provides a novel conjugated microporous polymer wave-absorbing material. The molecular structure of the conjugated microporous polymer is regulated by introducing a design strategy of a thiophene unit, so that the planarity of the molecular skeleton of the conjugated microporous polymer and the carrier ion capacity are effectively enhanced, and then the electromagnetic characteristics are significantly improved. In addition, the regulation of micropores can further improve the composite characteristics of the conductive polymer and enhance the wave-absorbing characteristics of the material. As an all-organic wave-absorbing material, in addition to the extremely high wave-absorbing performance at a specific wavelength, the material also has the characteristics of light weight, good compatibility with organic matter, adjustable wave-absorbing performance, and the like, and has a wide use scene and high practical value. The specific implementation is as follows.

[0052] Example 1: CMP-TH

[0053] In a 100 mL two-necked flask, 500 mg of 2,5-dibromothiophene, 953 mg of 1,3,5-tris(4-phenylboronic pinacol ester) benzene, 19 mg of tetrakis triphenylphosphine palladium, 1142 mg of potassium carbonate were added, and an oxygen-free treatment was performed. The reaction was carried out in a nitrogen protective atmosphere, 27 mL of N,N-dimethylformamide and 5 mL of water were injected into the reaction system, and stirring was carried out at 150 DEG C. After 72 h of reaction, the reaction was stopped, and the temperature was lowered to room temperature. The product was washed repeatedly with water and methanol, and then was subjected to cyclopentyl methyl ether extraction for 3 days. The product was dried at 100 DEG C under vacuum for 12 h to obtain a light yellow gray product, which was named as CMP-TH.

[0054] Example 1: CMP-TH development

[0055]

[0056] Example 2: CMP-TH-1

[0057] In a 100 mL two-necked flask, 660 mg of 2,5-dibromothiophene, 1235 mg of 1,3,5-tris(4-phenylboronic pinacol ester) benzene, 16 mg of [1,1'-bis(diphenylphosphino) ferrocene] dichloropalladium, and 3552 mg of cesium carbonate were added, and an oxygen-free treatment was performed. The reaction was carried out in a nitrogen protective atmosphere, 27 mL of N,N-dimethylformamide and 5 mL of water were injected into the reaction system, and stirring was carried out at 150 DEG C. After 72 h of reaction, the reaction was stopped, and the temperature was lowered to room temperature. The product was washed repeatedly with water and methanol, and then was subjected to cyclopentyl methyl ether extraction for 3 days. The product was dried at 100 DEG C under vacuum for 12 h to obtain a light yellow gray product, which was named as CMP-TH-1.

[0058] Example 2: CMP-TH-1 development

[0059]

[0060] Example 3

[0061] Add 100 mg CMP-TH (prepared in Example 1) and 300 mg pyrrole to a 250 mL single-necked flask, and then inject 100 mL of 1 mol·L⁻¹ into the reaction system. -1 The ferric chloride solution was stirred and reacted at room temperature for 4 hours. After repeated washing with a large amount of water and ethanol, the mixture was dried in a vacuum oven at 70°C to obtain a black powdery composite microwave absorbing material of conjugated microporous polymer and polypyrrole, which was named CMP-TH / PPy 1:3.

[0062] Example 3: Development of CMP-TH / PPy 1:3

[0063]

[0064]

[0065] Example 4

[0066] Add 100 mg CMP-TH (prepared in Example 1) and 500 mg pyrrole to a 250 mL single-necked flask, and then inject 100 mL of 1 mol·L⁻¹ into the reaction system. -1 The ferric chloride solution was stirred and reacted at room temperature for 4 hours. After repeated washing with a large amount of water and ethanol, the mixture was dried in a vacuum oven at 70°C to obtain a black powdery composite microwave absorbing material of conjugated microporous polymer and polypyrrole, which was named CMP-TH / PPy 1:5.

[0067] Example 4: Development of CMP-TH / PPy 1:5

[0068]

[0069] Example 5

[0070] The difference between this embodiment and Example 4 is that 100 mg CMP-TH and 100 mg pyrrole were used to prepare CMP-TH / PPy 1:1.

[0071] Example 6

[0072] The difference between this embodiment and Example 4 is that 10 mg CMP-TH and 100 mg pyrrole were used to prepare CMP-TH / PPy1:10.

[0073] Comparative Example 1: PPy

[0074] Add 1000 mg of pyrrole to a 250 mL single-necked flask, and then inject 100 mL of 1 mol·L⁻¹ solution into the reaction system. -1The mixture was stirred and reacted at room temperature for 4 h. The product was repeatedly washed with a large amount of water and ethanol, and dried in a vacuum oven at 70 DEG C to obtain a black powder of the composite wave-absorbing material of the conjugated microporous polymer and polypyrrole, and named as PPy. The preparation process is as follows:

[0075] Preparation of PPy

[0076]

[0077] Results and analysis

[0078] The conjugated microporous polymer containing thiophene units is synthesized, and the polypyrrole with a network structure is prepared by the confined polymerization of polypyrrole in the pores of the conjugated microporous polymer, as shown in the following formula: Figure 1 The material with the best wave-absorbing performance is found by controlling the mass ratio of the conjugated microporous polymer and polypyrrole.

[0079] The solid sample is subjected to scanning electron microscopy, solid nuclear magnetic resonance spectroscopy and XPS photoelectron spectroscopy tests to verify the correctness of the structure of the obtained product.

[0080] Scanning electron microscopy: as shown in the following formula: Figure 4 The material is subjected to gold spraying treatment, and the microstate thereof is observed using a scanning electron microscope. In a scale of 200 nm, the conjugated microporous polymer exists in the form of a spherical ball. The conjugated microporous polymer ball is unevenly distributed, from several tens of nanometers to more than 200 nanometers, and most of the balls are relatively complete without notches and the like. There is no obvious image interface like a crystal, which indicates the network crosslinking state of the polymer. The ball surface is smooth and uniform, which indicates the good uniformity of the material.

[0081] Solid nuclear magnetic resonance: the solid nuclear magnetic resonance of the conjugated microporous polymer is as shown in the following formula: Figure 5 The results prove that the CMP-TH is successfully prepared.

[0082] XPS photoelectron spectroscopy: as shown in the following formula: Figure 6 Through analysis of the XPS photoelectron spectroscopy total spectrum, it is found that the sulfur element accounts for 4.44%, and the carbon element accounts for 95.56%. Further analysis of the bonding state of carbon in the material is performed through the carbon fine spectrum. Through the peak separation of the carbon fine spectrum, it can be proved that the carbon-sulfur bond and the aromatic carbon exist. Finally, the proportion relationship of the composite sulfur 2p orbit is analyzed by performing peak separation processing on the sulfur fine spectrum. The results show that there is only one valence state of sulfur. Through the analysis of the photoelectron spectroscopy, it is further proved that the sulfur-containing conjugated microporous polymer is successfully prepared.

[0083] Scanning electron microscopy: as shown in the following formula: Figure 7As shown, the wave-absorbing material was subjected to gold spraying treatment, and its microstate was observed by scanning electron microscope. The pyrrole monomer was introduced into the micropores of the conjugated microporous polymer by the method of reduced pressure distillation, and then the polypyrrole was oxidized and polymerized by ferric trichloride, so that the polypyrrole grew in the micropores of the conjugated microporous polymer to construct a conductive network, forming a conductive conjugated microporous polymer microsphere with a diameter of about 200 nm. The excess pyrrole molecules continued to grow on the surface of the microsphere, resulting in small particles of polypyrrole on the surface of the microsphere. The cracks on the surface of the microsphere in the figure indicate that the polypyrrole has been successfully introduced into the micropores of the conjugated microporous polymer, and the surface particles indicate that the polypyrrole has been successfully prepared.

[0084] As shown in the infrared spectrum: Figure 8 After introducing polypyrrole into CMP-TH, its infrared spectrum is almost the same as that of polypyrrole, which proves that the polypyrrole has been successfully prepared.

[0085] The wave-absorbing materials of Examples 1-4 and Comparative Example 1 were filled into paraffin wax, and the ratio of paraffin wax to wave-absorbing material was 85:15. A concentric ring with an inner diameter of 3.04 mm, an outer diameter of 7 mm and a thickness of 2-5 mm was prepared, and the coaxial method was used to test the wave-absorbing materials in the frequency range of 2-18 GHz by a vector network analyzer. Figure 9 、 10 , 11, 12 correspond to CMP-TH / PPy 1:5, CMP-TH 1:3, polypyrrole and the comparison of the properties of the wave-absorbing material and polypyrrole, respectively;

[0086] As can be seen from Figures 9 to 11 , when the ratio of CMP-TH / PPy reaches 1:3 and 1:5, the minimum reflection loss of the two kinds of composite wave-absorbing materials reaches-39.80 dB and-34.24 dB, respectively. The minimum reflection loss of polypyrrole is only-19.19 dB. Therefore, the design strategy of inserting polypyrrole into the thienyl conjugated microporous polymer for compounding can significantly improve the wave-absorbing performance.

[0087] Figure 12 It is shown that under the condition of a thickness of 4.30 mm, the effective bandwidth of CMP-TH / PPy 1:3 below-10 dB reflection loss reaches 3.67 GHz (6.48 GHz to 10.15 GHz), and the reflection loss at 7.90 GHz reaches-73.68 dB. Compared with PPy, the effective bandwidth and reflection loss of the CMP-TH / PPy 1:3 composite material are significantly improved.

[0088] Figure 13It is shown that, in the case of a thickness of 2.04 mm, the effective bandwidth of CMP-TH / PPy 1:5 reaches 4.34 GHz (13.66 GHz to 18.00 GHz) at a reflection loss lower than -10 dB, while the reflection loss at 17.10 GHz reaches -67.18 dB, and the effective bandwidth and reflection loss of the effective absorption peak width composite material of CMP-TH / PPy 1:5 are significantly improved compared with PPy.

[0089] By Figure 12 、 13 In comparison, the novel thiophene conjugated microporous polymer developed in the application has a significant improvement in wave absorption characteristics in different frequency ranges compared with PPy by compounding and proportion control with PPy.

[0090] The conjugated microporous polymer containing thiophene units is successfully synthesized, and polypyrrole is introduced into the conjugated microporous polymer. The conjugated microporous polymer as the skeleton of polypyrrole not only adjusts the aggregation state of polypyrrole, but also has a wider effective absorption frequency band, and due to the good impedance matching skeleton between polypyrroles, the microwave energy is reflected between the polypyrroles, which significantly improves the maximum wave absorption intensity of the conjugated microporous polymer wave absorption material.

[0091] Although the application is disclosed as above, the application is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the application, and therefore the protection scope of the application should be subject to the range defined by the claims.

Claims

1. A thienyl conjugated microporous polymer wave-absorbing material, characterized in that, The wave-absorbing material is composed of a conjugated microporous polymer and a polypyrrole, the conjugated microporous polymer is formed by coupling polymerization of dibromothiophene monomers and borate monomers under the action of a palladium catalyst, and the polypyrrole is obtained by confined polymerization of polypyrrole in the pores of the conjugated microporous polymer, the conjugated microporous polymer has a structure as shown in I.

2. A method of producing the wave-absorbing material according to claim 1, characterized by, The method comprises the following steps: (1) preparing a conjugated microporous polymer Dibromothiophene monomers, borate monomers, a catalyst, and a carbonate are added to a two-neck flask, and oxygen-free treatment is performed, then organic solvent and water are added to the flask, and the mixture is stirred and heated to 150 DEG C for 72 hours, and then purified to obtain the conjugated microporous polymer; The reaction formula for preparing the conjugated microporous polymer is shown in formula IV: (2) preparing a wave-absorbing material The conjugated microporous polymer and pyrrole monomers are added to a single-neck flask, then ferric trichloride solution is added to the flask, and the mixture is stirred and reacted at room temperature for 4-5 hours, and then purified to obtain the wave-absorbing material.

3. The method of claim 2, wherein the wave-absorbing material is prepared by mixing the metal oxide and the metal salt in a solvent. The molar ratio of the dibromothiophene monomers to the borate monomers is 3:

2.

4. The method of claim 2, wherein the wave-absorbing material is prepared by mixing the metal oxide and the metal salt in a solvent. The dibromothiophene monomers are 2,5-dibromothiophene.

5. The method of claim 2, wherein the wave-absorbing material is prepared by mixing the metal oxide and the metal salt in a solvent. The borate monomers are 1,3,5-tris(4-phenylboronic pinacol ester) benzene.

6. The method of claim 2, wherein the wave-absorbing material is prepared by mixing the metal oxide and the metal salt in a solvent. The palladium catalyst is one of tetrakis(triphenylphosphine)palladium and [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium.

7. The method of claim 2, wherein the wave-absorbing material is prepared by a method comprising: preparing a mixture of a metal oxide and a polymer; and mixing the mixture with a solvent to prepare a solution. The mass ratio of the conjugated microporous polymer to the pyrrole monomers is 1:(1-10).

8. The method of claim 2, wherein the wave-absorbing material is prepared by a method comprising: preparing a mixture of a metal oxide and a polymer; and mixing the mixture with a solvent to prepare a solution. The concentration of the ferric chloride solution is 1 mol L -1 .

9. The method of claim 2, wherein the wave-absorbing material is prepared by a method comprising: preparing a mixture of a metal oxide and a polymer; and mixing the mixture with a solvent to prepare a solution. The volume ratio of the organic solvent to water is 27:5.

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