Super-long-acting moisture-resistant antifouling self-cleaning polymer nano-fiber dust removal filter membrane and preparation method thereof

Abstract

The invention provides an ultra-long-acting moisture-resistant antifouling self-cleaning polymer nano-fiber dedusting filter membrane and a preparation method thereof, the method comprises the following steps: step S1, dissolving polylactic acid and halogen monomers in a dissolving solution to prepare a core pre-constructed spinning solution; s2, preparing a core pre-constructed nano-fiber membrane from the core pre-constructed spinning solution obtained in the step S1 through a spinning process; s3, carrying out coherent crystallization on the core pre-constructed nano-fiber membrane obtained in the step S2, a rigid alkyne monomer and a catalyst in a reaction mixed solution in an inert gas atmosphere to prepare a moisture-resistant polymer coated nano-fiber membrane; and S4, mixing the moisture-resistant polymer coated nano-fiber membrane obtained in the step S3 with a sulfonating agent and a reaction solvent to prepare the super-long-acting moisture-resistant antifouling self-cleaning polymer nano-fiber dust removal filter membrane. The prepared nano-fiber filter membrane has a compact moisture-resistant polymer layer, an abundant sulfonated antifouling layer, high-efficiency particulate matter filtering capacity and excellent ammonia gas adsorption performance, and can be widely applied to the fields of industrial pollution control, energy environmental protection equipment, medical biological protection and the like.

Description

Technical Field

[0001] The present invention relates to the field of coherent crystallization strategies for moisture-resistant and anti-fouling functional layers and gas-solid pollutant synergistic purification membrane materials, and particularly to an ultra-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane and a preparation method thereof. Background Art

[0002] With the acceleration of the industrialization process and the expansion of the urbanization scale, the co-emission of atmospheric particulate matter (PM) and nitrogen-containing gaseous pollutants (such as NH3, nitrogen oxides) poses a severe challenge to the ecological environment and public health. Fine particulate matter (PM 0.3 ) can not only cause cardio-pulmonary diseases through the respiratory system, but the ammonia molecules adsorbed on its surface are more likely to participate in atmospheric chemical reactions as gaseous precursors, promoting the formation of secondary aerosols and resulting in a compound pollution effect. Traditional adsorption technologies are mostly designed for single pollutants and are difficult to synchronously treat heterogeneous multi-phase pollutant systems. In recent years, the synergistic filtration adsorption technology based on interfacial engineering regulation has received attention. By constructing a hierarchical pore structure composite material, it realizes the synergistic effect of physical interception of PM and chemical adsorption of NH3 - the micro-nano fiber network efficiently captures PM through electrostatic effects and inertial collisions, while the loaded acidic functional groups (such as carboxyl groups, sulfonic acid groups) can undergo protonation reactions with NH3 to form stable ammonium salts. However, the existing research still lacks a systematic analysis of the competitive adsorption mechanism of two-phase pollutants under dynamic conditions, the matching degree of surface active sites of materials, and long-term cycle stability, which restricts the application of this technology in actual complex working conditions.

[0003] Conjugated microporous polymers (CMPs) are a class of organic microporous polymers with a three-dimensional rigid network structure. Compared with traditional conjugated polymers or porous materials, their greatest feature is the presence of a π-conjugated backbone, highly adjustable structure and composition, and excellent physical and chemical stability (superhydrophobic and resistant to acid and alkali corrosion). As an emerging organic porous polymer, CMPs have been proven to be efficient in filtering inhalable particulate matter in the air. The Li team [J. Membr. Sci. 2022, 659:120728] synthesized CMPs aerogels (A-CMPs) containing aminopyridine molecules, which are used as an advanced filter for antibacterial and efficient capture of inhalable particulate matter. The A-CMPs aerogel achieved a long-lasting capture efficiency, with PM 2.5 ≥99.57±0.19%, PM 10≥99.98±0.01%, and can be recycled. However, CMPs synthesized by traditional methods often exhibit an amorphous powder-like morphology, which is not only insoluble and infusible but also greatly reduces their processability, limiting their wide application in effectively removing PM and other air pollutants. In addition, although it has been previously reported that CMP-based membranes or thin films can be used to capture PM, their relatively poor mechanical strength hinders their practical application. Therefore, there is an urgent need to seek effective strategies for fabricating high-value-added CMPs membranes with excellent mechanical properties.

[0004] In the forefront exploration of the fields of materials science and environmental governance, nanofiber membranes have attracted much attention due to their unique physicochemical properties and high specific surface area. Traditional spinning processes, such as electrospinning, melt spinning, solution blow spinning, and phase separation spinning, etc., have successfully achieved the large-scale preparation of various polymer nanofiber membranes. These nanofiber membranes have shown great application potential in fields such as air filtration, water treatment, biomedicine, and energy storage. However, with the increasing complexity of environmental problems, single-functional nanofiber membranes have become difficult to meet the urgent needs of modern society for high-performance composite materials. CMPs, with their precise conjugated structure, adjustable microporous characteristics, and excellent chemical stability, have become one of the ideal choices for constructing multifunctional composite materials. In recent years, the core pre-constructed coherent crystallization method, as an innovative composite material preparation strategy, has provided new ideas for the synergistic integration of nanofiber membranes and CMPs. This method triggers a polymerization reaction under specific conditions by pre-implanting the growth cores of CMPs in the nanofiber membranes, realizing the coherent crystallization of CMPs inside or on the surface of the nanofiber membranes. The coherent crystallization method can not only avoid the performance loss caused by poor interfacial compatibility in traditional composite processes but also give full play to the mechanical support role of the nanofiber membranes and the special functional characteristics of CMPs, thus creating new composite materials with unique advantages in fields such as gas adsorption, separation, sensing, and catalysis. The in-depth research and optimization of this strategy are expected to open up new ways for the design and application of high-performance composite materials and promote the continuous progress of related technologies. Summary of the Invention

[0005] The object of the present invention is to prepare an ultra-long-lasting anti-humidity, anti-fouling, and self-cleaning polymer nanofiber dust filter membrane to overcome the technical bottleneck that nanofiber filter membranes cannot simultaneously possess anti-humidity and anti-fouling characteristics and the synergistic purification of gas-solid pollutants, and to solve the deficiencies existing in the existing air purification filter element material technology.

[0006] To achieve the above object, the present invention provides an ultra-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane and a preparation method thereof. On the surface of the polylactic acid nanofiber membrane, a conjugated microporous polymer moisture-resistant layer is induced to co-crystallize through a core pre-construction strategy, and a sulfonation post-modification is carried out to increase the anti-fouling functional layer, so as to improve the synergistic purification ability of the filter membrane for fine particles and ammonia in a humid and oily environment.

[0007] According to the first aspect of the present invention, there is provided a preparation method of an ultra-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane, comprising the following steps: Step S1, preparing a core pre-construction spinning solution: dissolving polylactic acid and a halogen monomer in a solvent to prepare a core pre-construction spinning solution; Step S2, preparing a core pre-construction nanofiber membrane: subjecting the core pre-construction spinning solution obtained in Step S1 to a spinning process to prepare a core pre-construction nanofiber membrane; Step S3, preparing a moisture-resistant polymer-coated nanofiber membrane: subjecting the core pre-construction nanofiber membrane obtained in Step S2 to co-crystallization with a rigid alkyne monomer and a catalyst in a reaction mixture under an inert gas atmosphere to prepare a moisture-resistant polymer-coated nanofiber membrane; Step S4, preparing a sulfonated polymer moisture-resistant and anti-fouling nanofiber dust removal filter membrane: subjecting the moisture-resistant polymer-coated nanofiber membrane obtained in Step S3 to sulfonation post-modification with a sulfonating agent in a reaction solvent to prepare an ultra-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane.

[0008] Preferably, in Step S1, the polylactic acid is one or more of L-polylactic acid, D-polylactic acid, racemic polylactic acid, and meso-polylactic acid, and the solvent is one or more of dichloromethane, N,N-dimethylformamide, chloroform, trichloroethane, hexafluoroisopropanol, methyl acetate, ethyl acetate, acetone, butanone, toluene, xylene, tetrahydrofuran, and 1,4-dioxane; the mass fraction of polylactic acid in the solvent is 5-20%.

[0009] Preferably, in Step S1, the halogen monomer is one or more of a chlorine-containing aromatic monomer, a bromine-containing aromatic monomer, an iodine-containing aromatic monomer, a chlorine-containing heterocyclic monomer, a bromine-containing heterocyclic monomer, an iodine-containing heterocyclic monomer, a chlorine-containing olefin monomer, and a bromine-containing olefin monomer; the molar ratio of the halogen monomer to polylactic acid is 2:1 to 1:10.

[0010] Preferably, in Step S2, the spinning process is one or more of high-voltage electrospinning, high-speed solution blowing and spraying spinning, high-speed rotary centrifugal spinning, microfluidic spinning, phase separation spinning, emulsion spinning, dry spinning, and wet spinning processes; the thickness of the obtained core pre-construction nanofiber membrane is 50-500 μm, and the average diameter of the nanofibers is 50-800 nm.

[0011] Preferably, the spinning process in step S2 is a high-voltage electrospinning process, and the spinning parameters are set as follows: the spinning voltage is 5-40 kV, the solution feeding rate is 0.5-5 mL / h, the receiving distance is 10-30 cm, the temperature is 10-50 °C, and the humidity is 30-60% RH.

[0012] Preferably, the spinning process in step S2 is a high-speed solution blowing and spraying spinning process, and the spinning parameters are set as follows: the gas supply pressure is 0.1-1.0 MPa, the solution feeding rate is 1-10 mL / h, the receiving distance is 5-20 cm, the temperature is 20-40 °C, and the humidity is 20-40% RH.

[0013] Preferably, the spinning process in step S2 is a high-speed rotary centrifugal spinning process, and the spinning parameters are set as follows: the centrifugal rotation speed is 1000-20000 rpm, the solution feeding rate is 0.1-5 mL / h, the receiving distance is 10-30 cm, the temperature is 10-40 °C, and the humidity is 30-60% RH.

[0014] Preferably, the spinning process in step S2 is a microfluidic spinning process, and the spinning parameters are set as follows: the microchannel structure is one or more of a single channel, a coaxial double channel, a cross shape, and a Y-shaped mixer; the fluid driving rate is 5-500 μL / h, the driving pressure is 5-100 kPa, the receiving distance is 1-10 cm, the temperature is 20-40 °C, and the humidity is 20-60% RH.

[0015] Preferably, in step S3, the inert gas is one or more of nitrogen, helium, neon, argon, and xenon; the rigid alkyne monomer is one or more of phenylacetylene, naphthalene acetylene, anthracene acetylene, thiophene acetylene, pyrrole acetylene, and pyrene acetylene rigid monomers; the molar ratio of the rigid alkyne monomer to the functional group of the halogen monomer in the core prefabricated nanofiber membrane is 5:1-1:5.

[0016] Preferably, the catalyst in step S3 is a mixture of a palladium-based catalyst and a copper-based catalyst. The palladium-based catalyst is one or more of tetrakis(triphenylphosphine)palladium, palladium acetate, palladium dichloride, palladium trifluoroacetate, palladium on carbon, and dichlorobis(triphenylphosphine)palladium. The copper-based catalyst is one or more of cuprous iodide, cuprous bromide, cuprous chloride, copper acetate, copper sulfate, and copper chloride. The molar ratio of the palladium-based catalyst to the copper-based catalyst in the catalyst is 5:1-1:20.

[0017] Preferably, in step S3, the reaction mixture is a mixed solvent of a polar solvent and a basic solvent. The polar solvent is one or more of toluene, o-xylene, m-xylene, p-xylene, N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran, 1,4-dioxane, acetonitrile, dichloromethane, and chloroform. The basic solvent is one or more of triethylamine, tripropylamine, tributylamine, pyrrolidine, pyridine, quinoline, and isoquinoline. The volume ratio of the polar solvent to the basic solvent in the reaction mixture is 5:1 to 1:5. The temperature of the coherent crystallization reaction is 50 to 90 °C, and the time is 12 to 96 h.

[0018] Preferably, in step S4, the sulfonating agent is one or more of chlorosulfonic acid, benzenesulfonyl chloride, sulfamic acid, sulfuric acid, and fuming sulfuric acid. The molar ratio of the anti-moisture polymer-coated nanofiber membrane to the sulfonating agent is 1:1 to 1:10.

[0019] Preferably, in step S4, the reaction solvent is one or more of methanol, ethanol, acetone, dichloromethane, N,N-dimethylformamide, N-methylpyrrolidone, dimethyl sulfoxide, acetonitrile, water, and tetrahydrofuran. The reaction temperature for post-sulfonation modification is 20 to 80 °C, and the time is 0.5 to 48 h.

[0020] To achieve the above object, according to the second aspect of the present invention, the present invention also provides a nanofiber dust removal filter membrane obtained by the foregoing preparation method.

[0021] Preferably, the specific surface area of the obtained nanofiber dust removal filter membrane is 414 m 2 / g to 589 m 2 / g, the anti-moisture polymer loading rate is 66 to 73%, the water contact angle is 134 to 151°, the long-term filtration efficiency for PM 0.3 is 98.1 to 99.4%, and the ammonia adsorption capacity is 4.6 to 5.5 mmol / g.

[0022] Applying the technical solution of the present invention, the beneficial effects of the present invention are as follows: (1) Using halogen monomers as the core, by dissolving polylactic acid and halogen monomers in a solvent, a core-preformed spinning solution is prepared, and then a core-preformed nanofiber membrane is prepared through a spinning process, providing a good carrier and basis for the growth of subsequent functional layers; (2) In an inert gas atmosphere, the core-preformed nanofiber membrane, rigid alkyne monomers, and catalysts are subjected to coherent crystallization in a reaction mixture to successfully prepare a nanofiber membrane with a dense moisture-resistant polymer layer, effectively improving the stability and filtration performance of the filter membrane in a high-humidity environment and solving the problem of a significant decline in the performance of traditional filter membranes in a wet environment; (3) By sulfonating and modifying the moisture-resistant polymer-coated nanofiber membrane and sulfonating agent in a reaction solvent, a sulfonated anti-fouling functional layer is introduced, which not only enriches the surface chemical properties of the filter membrane but also significantly improves the anti-fouling performance and ammonia adsorption performance of the filter membrane, enabling it to efficiently remove particulate matter and harmful gases in the air; (4) The preparation method has a reasonable process, is easy to operate, and is suitable for large-scale production. The prepared nanofiber dust removal filter membrane has excellent comprehensive performance and can be widely applied to fields with strict requirements for air filtration and purification, such as industrial pollution control, energy environmental protection equipment, and medical biological protection.

[0023] The technical solution proposed by the present invention enables the ultra-long-lasting moisture-resistant, anti-fouling, and self-cleaning polymer nanofiber dust removal filter membrane to have a dense moisture-resistant polymer layer, a rich sulfonic acid anti-fouling layer, high-efficiency particulate matter filtration ability, and excellent ammonia adsorption performance. The present invention provides a method capable of inducing coherent crystallization of a conjugated microporous polymer moisture-resistant layer on the surface of a polylactic acid nanofiber membrane through a core-preformed strategy, and increasing the anti-fouling functional layer through post-sulfonation modification, improving the synergistic purification ability of the filter membrane for fine particulate matter and ammonia in a humid and oily environment, thereby broadening its application in fields such as industrial pollution control, energy environmental protection equipment, and medical biological protection, and having broad application prospects and important practical significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a schematic flow chart of the method of the present invention.

[0026] Figure 2 It is a scanning electron microscope image of the ultra-long-lasting moisture-resistant, anti-fouling, and self-cleaning polymer nanofiber dust removal filter membrane in Example 1.

[0027] Figure 3 It is an elemental mapping image of the ultra-long-lasting moisture-resistant, anti-fouling, and self-cleaning polymer nanofiber dust removal filter membrane in Example 1.

[0028] Figure 4 It is a transmission electron microscope image of the ultra-long-acting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane in Example 1.

[0029] Figure 5 It is a Fourier transform infrared spectroscopy diagram of the ultra-long-acting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane in Example 1.

[0030] Figure 6 It is an X-ray diffraction spectroscopy diagram of the ultra-long-acting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane in Example 1.

[0031] Figure 7 It is a scanning electron microscope image of the ultra-long-acting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane in Example 2.

[0032] Figure 8 It is a scanning electron microscope image of the ultra-long-acting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane in Example 3.

[0033] Figure 9 It is a scanning electron microscope image of the ultra-long-acting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane in Example 4. Detailed implementation manners

[0034] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation manners obtained by those of ordinary skill in the art without creative efforts shall fall within the scope protected by the present invention. The present invention will be described in detail below in conjunction with the embodiments.

[0035] Such as Figure 1As shown in the figure, Embodiment 1 of the present invention provides a method for preparing a super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane, which includes the following steps: Step S11, preparing a core pre-constructed spinning solution: dissolving poly(L-lactic acid) and the chlorinated aromatic monomer p-dichlorobenzene in dichloromethane (the mass fraction of poly(L-lactic acid) in dichloromethane is 10%, and the molar ratio of p-dichlorobenzene to poly(L-lactic acid) is 1:1) to prepare a core pre-constructed spinning solution; Step S12, preparing a core pre-constructed nanofiber membrane: subjecting the core pre-constructed spinning solution obtained in Step S11 to high-voltage electrospinning (the spinning voltage is 30 kV, the solution feeding rate is 1.5 mL / h, the receiving distance is 15 cm, the temperature is 20 °C, and the humidity is 30% RH) to prepare a core pre-constructed nanofiber membrane. The obtained nanofiber membrane has a thickness of 100 μm and an average nanofiber diameter of 300 nm; Step S13, preparing an anti-wetting polymer-coated nanofiber membrane: reacting the core pre-constructed nanofiber membrane obtained in Step S12 with the phenylacetylene-based rigid monomer 1,3,5-triethynylbenzene, tetrakis(triphenylphosphine)palladium, and copper iodide in a reaction mixture composed of toluene and triethylamine at 60 °C for 48 h for a coherent crystallization reaction (the functional group molar ratio of p-dichlorobenzene to 1,3,5-triethynylbenzene is 1:1, the molar ratio of tetrakis(triphenylphosphine)palladium to copper iodide is 1:1, and the volume ratio of toluene to triethylamine is 1:1) to prepare an anti-wetting polymer-coated nanofiber membrane; Step S14, preparing a sulfonated polymer anti-wetting, anti-fouling nanofiber dust removal filter membrane: reacting the anti-wetting polymer-coated nanofiber membrane obtained in Step S13 with chlorosulfonic acid (the molar ratio of the anti-wetting polymer-coated nanofiber membrane to chlorosulfonic acid is 1:3) in methanol at 40 °C for 12 h for a sulfonation modification reaction to prepare a super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane. The obtained nanofiber dust removal filter membrane has a specific surface area of 589 m 2 / g, an anti-wetting polymer loading rate of 73%, a hydrophobic angle of 151°, and a PM 0.3 long-term filtration efficiency of 99.4% and an ammonia adsorption capacity of 5.5 mmol / g.

[0036] As Figure 2 shown in the figure, the scanning electron microscope image of the core pre-constructed coherent crystallization-grown sulfonated polymer anti-wetting, anti-fouling and super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane obtained in Embodiment 1 of the present invention shows that CMPs are uniformly wrapped on the wall of the poly(lactic acid) nanofibers, forming a CMPs shell layer with strong π-conjugation and permanent micropores. The fibers are randomly arranged and the diameter differences are not significant. It can be clearly seen the poly(lactic acid) nanofiber tubes wrapping the fiber layer and the significant roughness on the fiber surface.

[0037] As Figure 3 shown in the figure, the element mapping image of the super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane obtained in Embodiment 1 of the present invention shows that carbon, oxygen, and sulfur elements are uniformly distributed on the surface of the nanofiber dust removal filter membrane, further proving the successful coherent crystallization of the sulfonated polymer shell layer on the surface of the poly(lactic acid) nanofibers.

[0038] As Figure 4 shown, the transmission electron microscope image of the ultra-long-lasting moisture-resistant, antifouling, and self-cleaning polymer nanofiber dust removal filter membrane obtained in Example 1 of the present invention shows that the sulfonated polymer shell is uniformly and densely co-crystallized on the surface of the polylactic acid nanofibers, and the surface exhibits a rough morphology.

[0039] As Figure 5 shown, the Fourier transform infrared spectroscopy diagram of the ultra-long-lasting moisture-resistant, antifouling, and self-cleaning polymer nanofiber dust removal filter membrane obtained in Example 1 of the present invention shows that stretching vibration signal peaks of specific functional groups such as hydroxyl groups, carbon-carbon double bonds, carbon-carbon triple bonds, sulfonic acid groups, and benzene rings exist in the nanofiber dust removal filter membrane.

[0040] As Figure 6 shown, the X-ray diffraction spectroscopy diagram of the ultra-long-lasting moisture-resistant, antifouling, and self-cleaning polymer nanofiber dust removal filter membrane obtained in Example 1 of the present invention shows that a relatively large broad peak appears in the material, proving that an amorphous structure is formed under kinetic control.

[0041] Example 2 of the present invention provides a preparation method of an ultra-long-lasting moisture-resistant, antifouling, and self-cleaning polymer nanofiber dust removal filter membrane, including the following steps: Step S21, preparing a core pre-constructed spinning solution: dissolving dextrorotatory polylactic acid and the bromine-containing aromatic monomer p-dibromobenzene in N,N-dimethylformamide (the mass fraction of dextrorotatory polylactic acid in N,N-dimethylformamide is 8%, and the molar ratio of p-dibromobenzene to dextrorotatory polylactic acid is 2:1) to prepare a core pre-constructed spinning solution; Step S22, preparing a core pre-constructed nanofiber membrane: subjecting the core pre-constructed spinning solution obtained in Step S21 to high-speed solution blowing and spraying spinning (the gas supply pressure is 0.6 MPa, the solution feeding rate is 2 mL / h, the receiving distance is 20 cm, the temperature is 30 °C, and the humidity is 30% RH) to prepare a core pre-constructed nanofiber membrane, the obtained nanofiber membrane has a thickness of 80 μm, and the average diameter of the nanofibers is 250 nm; Step S23, preparing a moisture-resistant polymer-coated nanofiber membrane: reacting the core pre-constructed nanofiber membrane obtained in Step S22 with the naphthyne-based rigid monomer 2,6-diethynylnaphthalene, palladium acetate, and copper bromide in a reaction mixture composed of o-xylene and tripropylamine at 50 °C for 24 h (the functional group molar ratio of p-dibromobenzene to 2,6-diethynylnaphthalene is 2:1, the molar ratio of palladium acetate to copper bromide is 2:1, and the volume ratio of o-xylene to tripropylamine is 2:1) to prepare a moisture-resistant polymer-coated nanofiber membrane; Step S24, preparing a sulfonated polymer moisture-resistant and antifouling nanofiber dust removal filter membrane: subjecting the moisture-resistant polymer-coated nanofiber membrane obtained in Step S23 to sulfonation and modification reaction with benzenesulfonyl chloride (the molar ratio of the moisture-resistant polymer-coated nanofiber membrane to benzenesulfonyl chloride is 1:2) in ethanol at 30 °C for 6 h to prepare an ultra-long-lasting moisture-resistant, antifouling, and self-cleaning polymer nanofiber dust removal filter membrane. The specific surface area of the obtained nanofiber dust removal filter membrane is 526 m 2 / g, the anti - wet polymer loading rate is 71%, the hydrophobic angle is 144°, and the PM 0.3 long - term filtration efficiency is 99.1%, and the ammonia adsorption capacity is 5.1 mmol / g.

[0042] As Figure 7 shown, the scanning electron microscope image of the super - long - lasting anti - wet, anti - fouling and self - cleaning polymer nanofiber dust - removing filter membrane obtained in Example 2 of the present invention shows that CMPs are uniformly wrapped on the wall of polylactic acid nanofibers, forming a CMPs shell layer with strong π - conjugation and permanent micropores. The fibers are randomly arranged and the diameter differences are not significant. It can be clearly seen the polylactic acid nanofiber tubes wrapping the fiber layer and the significant roughness on the fiber surface.

[0043] Example 3 of the present invention provides a preparation method of a super - long - lasting anti - wet, anti - fouling and self - cleaning polymer nanofiber dust - removing filter membrane, which includes the following steps: Step S31, preparing a core - pre - structured spinning solution: dissolving racemic polylactic acid and the iodine - containing aromatic monomer p - diiodobenzene in chloroform (the mass fraction of racemic polylactic acid in chloroform is 12%, and the molar ratio of p - diiodobenzene to racemic polylactic acid is 1:2) to prepare a core - pre - structured spinning solution; Step S32, preparing a core - pre - structured nanofiber membrane: subjecting the core - pre - structured spinning solution obtained in Step S31 to high - speed rotary centrifugal spinning (the centrifugal speed is 10,000 rpm, the solution feeding rate is 1.2 mL / h, the receiving distance is 15 cm, the temperature is 20 °C, and the humidity is 40% RH) to prepare a core - pre - structured nanofiber membrane. The obtained nanofiber membrane has a thickness of 120 μm and an average nanofiber diameter of 400 nm; Step S33, preparing an anti - wet polymer - coated nanofiber membrane: reacting the core - pre - structured nanofiber membrane obtained in Step S32 with the anthracene - alkyne rigid monomer 9,10 - diethynylanthracene, palladium dichloride and copper chloride in a reaction mixture composed of m - xylene and tributylamine at 65 °C for 72 h for a coherent crystallization reaction (the functional group molar ratio of p - diiodobenzene to 9,10 - diethynylanthracene is 1:2, the molar ratio of palladium dichloride to copper chloride is 1:2, and the volume ratio of m - xylene to tributylamine is 1:2) to prepare an anti - wet polymer - coated nanofiber membrane; Step S34, preparing a sulfonated polymer anti - wet and anti - fouling nanofiber dust - removing filter membrane: reacting the anti - wet polymer - coated nanofiber membrane obtained in Step S33 with sulfamic acid (the molar ratio of the anti - wet polymer - coated nanofiber membrane to sulfamic acid is 1:5) in acetone at 50 °C for 18 h for a sulfonation modification reaction to prepare a super - long - lasting anti - wet, anti - fouling and self - cleaning polymer nanofiber dust - removing filter membrane. The obtained nanofiber dust - removing filter membrane has a specific surface area of 473 m 2 / g, the anti - wet polymer loading rate is 69%, the hydrophobic angle is 139°, and the PM 0.3 long - term filtration efficiency is 98.5%, and the ammonia adsorption capacity is 4.9 mmol / g.

[0044] As Figure 8As shown, the scanning electron microscope image of the super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane obtained in Example 3 of the present invention shows that CMPs are evenly wrapped on the wall of the polylactic acid nanofiber tube, forming a CMPs shell layer with strong π-conjugation and permanent micropores. The fibers are randomly arranged and the tube diameters vary little. It can be clearly seen the polylactic acid nanofiber tube wrapping the fiber layer and the significant roughness on the fiber surface.

[0045] Example 4 of the present invention provides a preparation method of a super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane, which includes the following steps: Step S41, preparing a core pre-formed spinning solution: dissolving meso-polylactic acid and the chloroolefin monomer 1,2-dichloroethylene in hexafluoroisopropanol (the mass fraction of meso-polylactic acid in hexafluoroisopropanol is 14%, and the molar ratio of 1,2-dichloroethylene to meso-polylactic acid is 1:3) to prepare a core pre-formed spinning solution; Step S42, preparing a core pre-formed nanofiber membrane: subjecting the core pre-formed spinning solution obtained in Step S41 to microfluidic spinning (the microchannel structure is single-channel spinning, the fluid driving rate is 200 μL / h, the driving pressure is 50 kPa, the receiving distance is 6 cm, the temperature is 20 °C, and the humidity is 30% RH) to prepare a core pre-formed nanofiber membrane. The obtained nanofiber membrane has a thickness of 150 μm and an average nanofiber diameter of 500 nm; Step S43, preparing an anti-wetting polymer-coated nanofiber membrane: reacting the core pre-formed nanofiber membrane obtained in Step S42 with the thiophenylene-rigid monomer 2,5-diethynylthiophene, palladium trifluoroacetate and copper acetate in a reaction mixture composed of N,N-dimethylformamide and pyrrolidine at 70 °C for 96 h under an argon atmosphere (the functional group molar ratio of 1,2-dichloroethylene to 2,5-diethynylthiophene is 1:3, the molar ratio of palladium trifluoroacetate to copper acetate is 1:3, and the volume ratio of N,N-dimethylformamide to pyrrolidine is 1:3) to prepare an anti-wetting polymer-coated nanofiber membrane; Step S44, preparing a sulfonated polymer anti-wetting and anti-fouling nanofiber dust removal filter membrane: reacting the anti-wetting polymer-coated nanofiber membrane obtained in Step S43 with sulfamic acid (the molar ratio of the anti-wetting polymer-coated nanofiber membrane to sulfamic acid is 1:8) in acetone at 60 °C for 24 h for sulfonation and modification reaction to prepare a super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane. The obtained nanofiber dust removal filter membrane has a specific surface area of 414 m 2 / g, an anti-wetting polymer loading rate of 66%, a hydrophobic angle of 134°, and a PM 0.3 long-term filtration efficiency of 98.1% and an ammonia adsorption capacity of 4.6 mmol / g.

[0046] As Figure 9As shown, the scanning electron microscope image of the ultra-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane obtained in Example 4 of the present invention shows that CMPs are evenly wrapped on the wall of the polylactic acid nanofiber tube, forming a CMPs shell layer with strong π-conjugation and permanent micropores. The fibers are randomly arranged and have little difference in tube diameter. It can be clearly seen the polylactic acid nanofiber tube wrapping the fiber layer and the significant roughness on the fiber surface.

[0047] Comparative Example 1 of the present invention provides a method for preparing an ultra-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane, which basically uses the method of Example 1 to prepare the nanofiber dust removal filter membrane. The difference is that in this example, the core pre-construction strategy is not used to prepare the nanofiber dust removal filter membrane. Specifically, L-lactic acid is dissolved in dichloromethane (the mass fraction of L-lactic acid in dichloromethane is 10%) to prepare a polylactic acid spinning solution; the obtained polylactic acid spinning solution is subjected to high-voltage electrospinning (the spinning voltage is 30 kV, the solution feeding rate is 1.5 mL / h, the receiving distance is 15 cm, the temperature is 20 °C, and the humidity is 30% RH) to prepare a polylactic acid nanofiber membrane. The obtained nanofiber membrane has a thickness of 100 μm and an average nanofiber diameter of 300 nm; the obtained polylactic acid nanofiber membrane is subjected to a co-crystallization reaction at 60 °C for 48 h in a reaction mixture composed of toluene and triethylamine with p-dichlorobenzene, a rigid monomer of phenylacetylene 1,3,5-triethynylbenzene, tetrakis(triphenylphosphine)palladium and copper iodide (the molar ratio of p-dichlorobenzene to L-lactic acid is 1:1, the functional group molar ratio of p-dichlorobenzene to 1,3,5-triethynylbenzene is 1:1, the molar ratio of tetrakis(triphenylphosphine)palladium to copper iodide is 1:1, and the volume ratio of toluene to triethylamine is 1:1) to prepare an anti-wetting polymer-coated nanofiber membrane; the obtained anti-wetting polymer-coated nanofiber membrane and chlorosulfonic acid (the molar ratio of the anti-wetting polymer-coated nanofiber membrane to chlorosulfonic acid is 1:3) are subjected to a sulfonation post-modification reaction at 40 °C in methanol for 12 h to prepare an ultra-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane.

[0048] Comparative Example 2 of the present invention provides a method for preparing a super-long-lasting anti-moisture, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane, and the nanofiber dust removal filter membrane is basically prepared by the method of Example 2. The difference is that in this example, a flexible alkyne monomer is used to prepare the nanofiber membrane. Specifically, dextrorotatory polylactic acid and the bromine-containing aromatic monomer p-dibromobenzene are co-dissolved in N,N-dimethylformamide (the mass fraction of dextrorotatory polylactic acid in N,N-dimethylformamide is 8%, and the molar ratio of p-dibromobenzene to dextrorotatory polylactic acid is 2:1) to prepare a core pre-formed spinning solution; the obtained core pre-formed spinning solution is subjected to high-speed solution blowing and spraying spinning (the air supply pressure is 0.6 MPa, the solution feeding rate is 2 mL / h, the receiving distance is 20 cm, the temperature is 30 °C, and the humidity is 30% RH) to prepare a core pre-formed nanofiber membrane. The obtained nanofiber membrane has a thickness of 80 μm and an average nanofiber diameter of 250 nm; the obtained core pre-formed nanofiber membrane is subjected to a coherent crystallization reaction at 50 °C for 24 h in a reaction mixture composed of o-xylene and tripropylamine with the flexible alkyne monomer 3,4-diethynyl-3-hexene-1,5-diyne, palladium acetate and copper bromide (the functional group molar ratio of p-dibromobenzene to 3,4-diethynyl-3-hexene-1,5-diyne is 2:1, the molar ratio of palladium acetate to copper bromide is 2:1, and the volume ratio of o-xylene to tripropylamine is 2:1) to prepare an anti-moisture polymer-coated nanofiber membrane; the obtained anti-moisture polymer-coated nanofiber membrane and benzenesulfonyl chloride (the molar ratio of the anti-moisture polymer-coated nanofiber membrane to benzenesulfonyl chloride is 1:2) are subjected to a sulfonation post-modification reaction at 30 °C in ethanol for 6 h to prepare a super-long-lasting anti-moisture, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane.

[0049] Comparative Example 3 of the present invention provides a method for preparing a super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane, and the nanofiber dust removal filter membrane is basically prepared by the method of Example 3. The difference is that in this example, post-sulfonation modification is not carried out to prepare the nanofiber dust removal filter membrane. Specifically, racemic polylactic acid and p-diiodobenzene, an iodine-containing aromatic monomer, are co-dissolved in chloroform (the mass fraction of racemic polylactic acid in chloroform is 12%, and the molar ratio of p-diiodobenzene to racemic polylactic acid is 1:2) to prepare a core pre-structured spinning solution; the obtained core pre-structured spinning solution is subjected to high-speed rotary centrifugal spinning (the centrifugal speed is 10,000 rpm, the solution feeding rate is 1.2 mL / h, the receiving distance is 15 cm, the temperature is 20 °C, and the humidity is 40% RH) to prepare a core pre-structured nanofiber membrane. The obtained nanofiber membrane has a thickness of 120 μm and an average nanofiber diameter of 400 nm; the obtained core pre-structured nanofiber membrane is subjected to a coherent crystallization reaction at 65 °C for 72 h in a reaction mixture composed of m-xylene and tributylamine with 9,10-diethynylanthracene, palladium dichloride and copper chloride (the functional group molar ratio of p-diiodobenzene to 9,10-diethynylanthracene is 1:2, the molar ratio of palladium dichloride to copper chloride is 1:2, and the volume ratio of m-xylene to tributylamine is 1:2) in a neon atmosphere to prepare a super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane.

[0050] The structural characterization and performance testing are as follows.

[0051] Scanning electron microscope observation: The microstructure of the super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane was observed by a field emission scanning electron microscope (model JSM-7900F, JEOL, Japan) ( Figure 2 、 Figure 7 、 Figure 8 、 Figure 9 ).

[0052] Surface element distribution test: The surface element distribution of the super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane was recorded by an energy dispersive X-ray spectrometer (model Vario EL, JEOL, Japan) ( Figure 3 ).

[0053] Transmission electron microscope observation: The internal characteristics of the super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane were observed by a transmission electron microscope (model TECNI G2 TF20, FEI) ( Figure 4 ).

[0054] Functional group structure test: The functional groups of the super-long-lasting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane were recorded by an infrared spectrometer (model VERTEX 70, Bruker, USA) ( Figure 5 ).

[0055] Crystal structure test: The crystal structure of the super-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane was recorded using an X-ray spectrometer (model D / Max-2400, Rigaku Corporation, Japan). Figure 6 )

[0056] Filtration performance test: The air filtration performance of the super-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane (with an area of 25 cm 2 ) was tested using a CLJ-3016 laser dust particle counter (Shenzhen Huachengchang Machinery Experiment Co., Ltd.). The gas flow rate was set at 50 L / min. Each group of filter membranes was tested at least at 3 different positions, and the results were averaged.

[0057] Gas adsorption performance test: The NH3 adsorption of the super-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane was carried out using a gas adsorption instrument (ASAP 2020, Micromeritics, USA). High-purity gas NH3 (99.999%) was used for adsorption measurement, while the free space was measured with helium gas (99.999%). Isothermal adsorption was carried out at 273 K (ice-water bath).

[0058] Experimental results: As shown in Figure 2 , Figure 7 , Figure 8 and Figure 9 , the scanning electron microscope images of the super-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane show that CMPs are evenly wrapped on the walls of the polylactic acid nanofibers, forming a CMPs shell layer with strong π-conjugation and permanent micropores. The fibers are randomly arranged and the tube diameters do not vary much. The polylactic acid nanofiber tubes wrapped with fiber layers and the significant roughness on the fiber surface can be clearly seen.

[0059] As shown in Figure 3 , the element mapping images of the super-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane show that carbon, oxygen, and sulfur elements are evenly distributed on the surface of the nanofiber dust removal filter membrane, further proving the successful epitaxial crystallization of the sulfonated polymer shell layer on the surface of the polylactic acid nanofibers.

[0060] As shown in Figure 4 , the transmission electron microscope images of the super-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane show that the sulfonated polymer shell layer is evenly and densely epitaxially crystallized on the surface of the polylactic acid nanofibers, and the surface presents a rough morphology.

[0061] As shown in Figure 5 , the Fourier transform infrared spectroscopy diagram of the super-long-lasting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane shows stretching vibration signal peaks of specific functional groups such as hydroxyl groups, carbon-carbon double bonds, carbon-carbon triple bonds, sulfonic acid groups, and benzene rings in the nanofiber dust removal filter membrane.

[0062] AsFigure 6 As shown in Figure 6 , the X-ray diffraction spectrogram of the super-long-acting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane shows a large wide peak in the material, proving that an amorphous structure is formed under kinetic control.

[0063] Table 1 compares the specific surface area, anti-wetting polymer loading rate, water contact angle, PM 0.3 long-term filtration efficiency and ammonia adsorption capacity results of the super-long-acting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membranes obtained in the examples and comparative examples.

[0064] Project Group <![CDATA[Specific surface area (m 2 / g)]]> Anti - moisture Polymer Loading Rate (%) Water Contact Angle (°) <![CDATA[PM 0.3 Long-term filtration efficiency (%)]]> Ammonia Adsorption Capacity (mmol / g) Example 1 589 73 151 99.4 5.5 Example 2 526 71 144 99.1 5.1 Example 3 473 69 139 98.5 4.9 Example 4 414 66 134 98.1 4.6 Comparative Example 1 117 24 92 82.3 1.3 Comparative Example 2 153 37 76 79.8 1.7 Comparative Example 3 138 31 83 81.4 1.1 Examples 1 to 4 have a large specific surface area (414 m 2 / g to 589 m 2 / g) and a high anti-wetting polymer loading rate (66 - 73%). This is because the preparation method of the super-long-acting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane is adopted. By dissolving polylactic acid and halogen monomers in a dissolution solution, a core pre-structured spinning solution is prepared, and then a core pre-structured nanofiber membrane is prepared through a spinning process, providing a good carrier and basis for the growth of the subsequent functional layer. The specific surface area of Comparative Examples 1 to 3 is only 117 - 153 m 2 / g, and the anti-wetting polymer loading rate is 24 - 37%. This is because the ordered self-assembly and coherent crystallization of the anti-wetting polymer are not controlled, thus affecting the growth process and pore properties.

[0065] The long-term particulate filtration performance and ammonia adsorption capacity of the super-long-acting anti-wetting, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane are closely related to the specific surface area, anti-wetting polymer loading rate and water contact angle. The PM 0.3 long-term filtration efficiency of Examples 1 to 4 with a large specific surface area, a high anti-wetting polymer loading rate and a large water contact angle is all above 98.1%, and the ammonia adsorption capacity is all above 4.6 mmol / g. Among them, Example 1 with the largest specific surface area, the highest anti-wetting polymer loading rate and the largest water contact angle performs the best in particulate filtration and ammonia adsorption tests, with a PM 0.3 long-term filtration efficiency of 99.4% and an ammonia adsorption capacity of 5.5 mmol / g. Far higher than Comparative Examples 1 to 3 with a small specific surface area, a low anti-wetting polymer loading rate and a small water contact angle (PM 0.3 long-term filtration efficiency ≤ 82.3%, ammonia adsorption capacity ≤ 1.7 mmol / g).

[0066] The present invention provides an ultra-long-acting moisture-resistant, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane and a preparation method thereof. There are many specific methods and ways to implement this technical solution. The above is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention. Each component not clearly defined in this embodiment can be implemented by using the prior art.

Claims

1. Preparation method of super-long-acting anti-moisture, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane, characterized in that, It includes the following steps: Step S1: Dissolve polylactic acid and a halogen monomer in a solvent to prepare a core pre-formed spinning solution; Step S2: Subject the core pre-formed spinning solution obtained in Step S1 to a spinning process to prepare a core pre-formed nanofiber membrane; Step S3: Mix the core pre-formed nanofiber membrane obtained in Step S2 with a rigid alkyne monomer, a reaction mixture, and a catalyst in an inert gas atmosphere to prepare a moisture-resistant polymer-coated nanofiber membrane; Step S4: Mix the moisture-resistant polymer-coated nanofiber membrane obtained in Step S3 with a sulfonating agent and a reaction solvent to prepare a super-long-lasting moisture-resistant, anti-fouling, and self-cleaning polymer nanofiber dust filter membrane.

2. The preparation method of the ultra-long-acting anti-humidity, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane according to claim 1, characterized in that, In Step S1, the polylactic acid is one or more of L-polylactic acid, D-polylactic acid, racemic polylactic acid, and meso-polylactic acid; the solvent is one or more of dichloromethane, N,N-dimethylformamide, chloroform, trichloroethane, hexafluoroisopropanol, methyl acetate, ethyl acetate, acetone, butanone, toluene, xylene, tetrahydrofuran, and 1,4-dioxane; the mass fraction of polylactic acid in the solvent is 5% to 20%.

3. The preparation method of the super-long-lasting anti-humidity, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane according to claim 1, characterized in that In Step S1, the halogen monomer is one or more of a chlorine-containing aromatic monomer, a bromine-containing aromatic monomer, an iodine-containing aromatic monomer, a chlorine-containing heterocyclic monomer, a bromine-containing heterocyclic monomer, an iodine-containing heterocyclic monomer, a chlorine-containing olefin monomer, and a bromine-containing olefin monomer; the molar ratio of the halogen monomer to the polylactic acid is 2:1 to 1:

10.

4. The preparation method of the super-long-acting anti-moisture, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane according to claim 1, characterized in that In Step S2, the spinning process is one or more of high-voltage electrospinning, high-speed solution blowspinning, high-speed rotary centrifugal spinning, microfluidic spinning, phase separation spinning, emulsion spinning, dry spinning, and wet spinning; the thickness of the obtained core pre-formed nanofiber membrane is 50 to 500 μm, and the average diameter of the nanofibers is 50 to 800 nm.

5. The preparation method of the super-long-acting anti-moisture, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane according to claim 1, characterized in that, In Step S3, the inert gas is one or more of nitrogen, helium, neon, argon, and xenon; the rigid alkyne monomer is one or more of phenylacetylene-based, naphthaleneacetylene-based, anthraceneacetylene-based, thiopheneacetylene-based, pyrroleacetylene-based, and pyreneacetylene-based rigid monomers; the molar ratio of the rigid alkyne monomer to the functional group of the halogen monomer in the core pre-formed nanofiber membrane is 5:1 to 1:

5.

6. The preparation method of the ultra-long-acting anti-humidity, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane according to claim 1, characterized in that, In Step S3, the catalyst is a mixture of a palladium-based catalyst and a copper-based catalyst, and the molar ratio of the palladium-based catalyst to the copper-based catalyst is 5:1 to 1:20; the palladium-based catalyst is one or more of tetrakis(triphenylphosphine)palladium, palladium acetate, palladium dichloride, palladium trifluoroacetate, palladium on carbon, and dichlorobis(triphenylphosphine)palladium; the copper-based catalyst is one or more of cuprous iodide, cuprous bromide, cuprous chloride, copper acetate, copper sulfate, and copper chloride.

7. The preparation method of the super-long-lasting anti-wet anti-fouling self-cleaning polymer nanofiber dust removal filter membrane according to claim 1, characterized in that, In the step S3, the reaction mixture is a mixed solvent of a polar solvent and a basic solvent, and the volume ratio of the polar solvent to the basic solvent is 5:1 to 1:5; the polar solvent is one or more of toluene, o-xylene, m-xylene, p-xylene, N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran, 1,4-dioxane, acetonitrile, dichloromethane, chloroform; the basic solvent is one or more of triethylamine, tripropylamine, tributylamine, pyrrolidine, pyridine, quinoline, isoquinoline; the mixing conditions in the step S3 are that the temperature is 50-90 °C and the time is 12-96 h.

8. The preparation method of the super-long-lasting anti-moisture, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane according to claim 1, characterized in that, In the step S4, the sulfonating agent is one or more of chlorosulfonic acid, benzenesulfonyl chloride, sulfamic acid, sulfuric acid, fuming sulfuric acid; the molar ratio of the anti-moisture polymer-coated nanofiber membrane to the sulfonating agent is 1:1 to 1:

10.

9. The preparation method of the super-long-acting anti-humidity, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane according to claim 1, characterized in that, In the step S4, the reaction solvent is one or more of methanol, ethanol, acetone, dichloromethane, N,N-dimethylformamide, N-methylpyrrolidone, dimethyl sulfoxide, acetonitrile, water, tetrahydrofuran; the mixing conditions in the step S4 are that the temperature is 20-80 °C and the time is 0.5-48 h.

10. A nanofiber dust removal filter membrane prepared by the method for preparing a super-long-lasting anti-moisture, anti-fouling and self-cleaning polymer nanofiber dust removal filter membrane according to any one of claims 1-9.

Images