Poly (arylene ether nitrile) nanofiber membrane and preparation method of double-solvent synergistic electrostatic spinning of poly (arylene ether nitrile) nanofiber membrane

Abstract

The invention discloses a polyarylene ether nitrile nanofiber membrane and a preparation method of the polyarylene ether nitrile nanofiber membrane through double-solvent synergistic electrostatic spinning, and relates to the field of high polymer material preparation. The method comprises the following steps: preparing two electrostatic spinning solutions with obvious volatilization rate and dissolution parameter difference, and alternately depositing two types of fibers on a collecting surface by adopting dual-channel synergistic electrostatic spinning; in the deposition and drying process, chain segments at fiber cross points are induced to swell, mutually diffuse and cure in situ to form bonding points by utilizing the poor evaporation rate of a high / low volatile solvent and the poor solvent-polymer compatibility, so that the self-densification and the structure stabilization of the nanofiber membrane are realized. The obtained nanofiber membrane has high-density in-situ bonding points and remarkably improved mechanical properties, does not need additional post-treatment such as hot pressing or solvent spraying, and is suitable for application such as interlayer reinforcement and interface toughening of composite materials. The process has continuity and controllability, and the density and mechanical properties of the membrane body can be customized by adjusting a solvent system and spinning parameters.

Description

Technical Field

[0001] This invention relates to the field of polymer material preparation, specifically to a polyarylene ether nitrile nanofiber membrane and its preparation method by dual-solvent synergistic electrospinning. Background Technology

[0002] Polyarylene ether nitrile (PEN) is a class of aromatic polymers with benzene rings, ether bonds, and nitrile groups. Due to its high glass transition temperature, excellent thermal stability, dimensional stability, and chemical resistance, it has become an important engineering material in fields such as high-temperature filtration, thermal insulation of electronic devices, electrical insulating membranes, and aerospace. In recent years, researchers have begun to use PEN to prepare nanofiber membranes in order to obtain high specific surface area, excellent toughness, and mechanical properties.

[0003] Electrospinning is a common method for preparing PEN nanofiber membranes. However, PEN nanofiber membranes prepared by this method often suffer from loose fiber webs and weak bonding at fiber intersections, resulting in insufficient overall membrane strength, easy peeling from the substrate, or failure to maintain the integrity of the entire membrane. Common techniques used to address these issues, such as solvent softening, hot pressing, and blending low-melting-point components into the spinning raw materials, can enhance fiber bonding, but usually require additional post-processing and may damage the pore structure or morphology of the nanofibers. For example, hot pressing can easily lead to fiber melting and adhesion, pore collapse, or even blockage.

[0004] In the prior art, various methods have been developed to enhance the bonding force between fibers within electrospun nanofiber membranes. For example, CN120425507A uses solvent spraying to treat the formed fiber membrane, softening the fiber surface with the solvent vapor phase, causing local swelling and solidification at the intersections to form bonding points; CN103541149A introduces low-melting-point blend components into the fiber system, or applies hot pressing / rolling after film formation, causing the low-melting-point components to melt and solidify at the intersections to achieve bonding; CN104028047B and CN120350558A focus on controlling the spinning environment, controlling the fiber drying rate by maintaining specific solvent vapor concentrations or humidity, thereby promoting bonding at fiber intersections. While these methods effectively enhance bonding, they all rely on additional post-processing steps or complex equipment control.

[0005] Although the specific methods differ—including solvent spraying, hot pressing and blending, or controlling the vapor environment—these existing technologies generally face a common limitation: while achieving adhesion, it is often difficult to avoid damaging or sacrificing the nanomorphology and porous structure of the fibers themselves, such as causing problems like pore collapse and fiber fusion.

[0006] Therefore, how to prepare single polyarylether nitrile nanofiber membranes by achieving high-density, controlled bonding at the intersection points through a simpler and more continuous process without sacrificing porosity and fiber morphology remains a technical challenge for industrialization and patent protection. Summary of the Invention

[0007] The purpose of this invention is to provide a dual-solvent in-situ bonding method based on differential solubility and compatibility parameters. This method utilizes the volatilization behavior and compatibility (δ) of two solvents (high volatility and low volatility) under saturated vapor pressure during the spinning process. T Significant differences in solvent concentration (values) create local solvent concentration gradients and rate differences, inducing swelling, interdiffusion, and recrystallization of polyarylether ether nitrile segments at fiber intersections. This process yields a dense polyarylether ether nitrile nanofiber membrane with good toughness and processability. The process naturally forms in-situ bonding points at fiber intersections, without relying on additional solvent spraying or hot pressing. This maintains the pore structure and morphology of the nanofibers while significantly improving the membrane's structural density and tensile properties, thereby enhancing the toughness and layability of the polyarylether ether nitrile fiber membrane.

[0008] To achieve the above objectives, this invention discloses a method for preparing polyarylether nitrile nanofiber membranes via dual-solvent synergistic electrospinning, comprising the following steps: (1) Preparation of dual-solvent electrospinning solution: Polyarylene ether nitrile was dissolved in a high-volatility solvent system and a low-volatility solvent system with different solubility and compatibility parameters to obtain two electrospinning solutions with different properties, namely, the first electrospinning solution S1 and the second electrospinning solution S2. (2) Preparation of self-densified nanofiber membrane: Using dual-channel synergistic electrospinning, the first electrospinning solution S1 and the second electrospinning solution S2 prepared in step (1) are loaded into independent spinning channels and spun, so that the two types of fibers are deposited alternately on the same collection surface. The difference in solvent parameters is used to induce the chain segment swelling, interdiffusion and recrystallization at the interface, thereby forming in-situ bonding points at the fiber intersection and realizing the self-densified structure. (3) Drying and structural stabilization: The nanofiber membrane is dried to remove residual solvent and fix its internal bonding network to obtain a polyarylether nitrile nanofiber membrane with a high density bonding network.

[0009] Preferably, in step (1), the polyarylene ether nitrile is a phenolphthalein-type polyarylene ether nitrile or a bisphenol A-type polyarylene ether nitrile with a weight-average molecular weight of 80,000 to 120,000.

[0010] Preferably, in step (1), the mass fraction of solute in the first electrospinning solution S1 and the second electrospinning solution S2 is the same, both being 16~20%.

[0011] Preferably, in step (1), the saturated vapor pressure of the highly volatile solvent at 25°C is in the range of 10~20 kPa, and the Hansen solubility parameter δ T 18~20 MPa 1 / 2 ; The saturated vapor pressure of the low-volatility solvent system at 25°C ranges from 10 to 100 Pa, and the Hansen solubility parameter δ... T 21~23 MPa 1 / 2 .

[0012] Preferably, in step (1), the solvent for the high-volatility system is either tetrahydrofuran or acetone, and the solvent for the low-volatility system is either N-methylpyrrolidone or dihydrol-glucanone.

[0013] Preferably, the principle of dual-solvent-induced in-situ bonding in step (1) based on the difference in solubility and compatibility parameters is as follows: The high-volatility system solvent has a low boiling point and a high saturated vapor pressure, which can evaporate rapidly during the spinning process, allowing the polyarylether nitrile molecular chains to solidify rapidly at the moment of deposition, forming a fiber skeleton with rigidity and shape retention. Hansen solubility parameter δ of solvents in highly volatile systems T Below the δ of polyarylether nitrile T The value of the polar nitrile group of the polymer has limited interaction with the rigid aromatic ring structure, so the fiber surface has low compatibility with other fibers, which is beneficial to maintaining the independent fiber morphology and pore structure after rapid molding. The low-volatility system has a high solvent boiling point and low saturated vapor pressure, which retains a high amount of solvent residue during the deposition stage, keeping the polyarylether acrylonitrile fibers in a semi-solid or surface-softened state. Hansen solubility parameter δ of solvents in low-volatility systems T Higher than the δ of polyarylether nitrile T The solvent has a higher solvation capacity for nitrile and ether bond sites, thereby promoting segment migration and local swelling. When fibers obtained from low-volatile solvents are interleaved with fibers obtained from high-volatile solvents, the segments undergo interdiffusion and recrystallization in the interfacial region, generating in-situ bonding points at the fiber intersections. This enhances the compactness and mechanical stability of the membrane while preventing the collapse of the overall membrane structure.

[0014] When fibers obtained from high and low volatile solvents are deposited and contacted alternately, a transient solvent concentration and compatibility gradient is formed in the fiber intersection region, driving interdiffusion and recrystallization of chain segments, generating high-density in-situ bonding points. That is, the bonding structure is formed at the fiber intersection through interdiffusion and recrystallization of chain segments. This process achieves self-densification and reinforcement of the fiber membrane without destroying the fiber morphology and pore structure.

[0015] Preferably, in step (2), the spinning flow rate of the first electrospinning solution S1 is 1.6~4.8 mL / h, the positive and negative voltages are +10~+25 kV and -7~-10 kV respectively, the receiving distance is 10~20 cm, the operating temperature is 20~40℃, the relative humidity of the environment is 30~75%, the inner diameter of the electrospinning needle is 0.5~0.8 mm, and the rotation speed of the receiving roller is 300~400 rpm.

[0016] Preferably, in step (2), the spinning flow rate of the second electrospinning solution S2 is 0.2~1.6 mL / h, the positive and negative voltages are +10~+25 kV and -7~-10 kV respectively, the receiving distance is 10~20 cm, the operating temperature is 20~40℃, the relative humidity of the environment is 30~75%, the inner diameter of the electrospinning needle is 0.5~0.8 mm, and the rotation speed of the receiving roller is 300~400 rpm.

[0017] Preferably, in step (3), the nanofiber membrane is dried in an air atmosphere at a temperature of 100-140°C for 24-48 hours.

[0018] The present invention also provides a polyarylene ether nitrile nanofiber membrane prepared by the above preparation method, which has a uniform and stable porous structure. The nanofibers inside the membrane fuse with each other through high-density bonding points formed in situ at the intersection points to form an integrated three-dimensional / two-dimensional network.

[0019] Preferably, the bonding point density ranges from 500 to 800 per mm. 2 The areal density of the polyarylene ether nitrile nanofiber membrane is 1.0 × 10⁻⁶. -3 ~2.0×10 -3 g / cm 2 .

[0020] Therefore, the present invention has the following beneficial effects: (1) This invention proposes a novel solution to the problem of loose structure in existing polyarylether nitrile nanofiber membranes due to weak inter-fiber bonding. Existing technologies typically rely on post-processing such as hot pressing or solvent treatment to achieve densification, but these methods often damage the fiber nanostructure and reduce porosity. This invention utilizes a precisely designed dual-solvent synergistic spinning system to induce in-situ bonding at the cross-points during fiber formation, thereby directly constructing an integrated three-dimensional / two-dimensional network structure with high density and high-strength bonding points in a single step, without any additional post-processing steps. This method not only simplifies the process but also fundamentally improves the structural controllability and performance repeatability of the product.

[0021] (2) The polyarylene ether nitrile nanofiber membrane prepared by the method of the present invention exhibits excellent comprehensive performance. Its uniform and stable high-density bonding network gives the material excellent toughness on a macroscopic scale, while also giving the membrane outstanding strength, overcoming the shortcomings of weak mechanical properties of traditional electrospun membranes. In addition, the membrane has excellent dimensional stability and layability. Attached Figure Description

[0022] Figure 1 The preparation method process provided by this invention; Figure 2 The electron microscope image shows the polyarylene ether nitrile nanofiber membrane with a high-density bonding point network prepared in Example 1. Figure 3 The electron microscope image shows the polyarylene ether nitrile nanofiber membrane with a high-density bonding point network prepared in Example 1. Figure 4 The stress-strain curves are for the polyarylene ether nitrile nanofiber membranes prepared in Examples 1-3. Detailed Implementation

[0023] This invention employs a dual-solvent in-situ bonding method based on differences in solubility and compatibility parameters. This method is based on the differences in boiling point, vapor pressure, and Hansen solubility parameter (δ) between the two solvent systems. T Differences in key parameters such as [specific parameters not provided] lead to significant variations in their compatibility and solvation capabilities with polyarylether nitrile molecular chains. Specifically, polyarylether nitrile was dissolved in both high-volatility and low-volatility solvent systems to prepare two solutions, which were then simultaneously electrospun in separate syringes, allowing the fibers to be mixed and deposited at the collection device. During deposition, the fibers in the high-volatility solvent system rapidly solidified and provided structural support, while the fibers in the low-volatility solvent system, due to higher solvent residue and slower drying rate, remained in a softened state. When the two systems came into contact at their intersection, a local gradient of solvent concentration / evaporation rate and compatibility difference was formed, driving chain segment swelling and interdiffusion, thereby generating localized, transient in-situ bonding points. As the deposition time increased or the number of layers increased, these bonding points gradually solidified, ultimately yielding a nanofiber membrane that is both dense and maintains porosity and permeability, thus significantly improving mechanical stability. Unlike traditional methods that rely on a single high-boiling-point system to control spinning parameters, this invention achieves highly selective in-situ cross-point bonding by establishing controlled local dynamic conditions during the transient deposition phase, thus avoiding overall film softening or collapse. This unique mechanism of "differential parameter driving, parallel deposition, and local bonding" is difficult to achieve naturally under stable spinning conditions with a single solvent system.

[0024] Based on the above principles, this invention discloses a method for preparing polyarylether nitrile nanofiber membranes by dual-solvent synergistic electrospinning, such as... Figure 1As shown, it includes the following steps: (1) Preparation of dual-solvent electrospinning solution: Polyarylene ether nitrile was dissolved in a high-volatility solvent system and a low-volatility solvent system with different solubility and compatibility parameters to obtain two electrospinning solutions with different properties, namely, the first electrospinning solution S1 and the second electrospinning solution S2.

[0025] (2) Preparation of self-densified nanofiber membrane: Using dual-channel synergistic electrospinning, the first electrospinning solution S1 and the second electrospinning solution S2 prepared in step (1) are loaded into independent spinning channels and spun, so that the two types of fibers are deposited alternately on the same collection surface. The difference in solvent parameters is used to induce the chain segment swelling, interdiffusion and recrystallization at the interface, thereby forming in-situ bonding points at the fiber intersection and realizing the self-densified structure.

[0026] (3) Drying and structural stabilization: The nanofiber membrane is dried to remove residual solvent and fix its internal bonding network to obtain a polyarylether nitrile nanofiber membrane with a high density bonding network.

[0027] In step (1), the polyarylene ether nitrile is phenolphthalein type polyarylene ether nitrile or bisphenol A type polyarylene ether nitrile, with a weight average molecular weight of 80,000~120,000.

[0028] In step (1), the mass fraction of solute in the first electrospinning solution S1 and the second electrospinning solution S2 is the same, both being 16~20%.

[0029] In step (1), the saturated vapor pressure of the solvent in the high-volatility system at 25°C ranges from 10 to 20 kPa, and the Hansen solubility parameter δ T 18~20 MPa 1 / 2 The saturated vapor pressure of the low-volatility solvent at 25°C ranges from 10 to 100 Pa, and the Hansen solubility parameter δ... T 21~23 MPa 1 / 2 .

[0030] In step (1), the solvent for the high-volatility system is either tetrahydrofuran or acetone, and the solvent for the low-volatility system is either N-methylpyrrolidone or dihydrol-glucanone.

[0031] In step (2), the spinning flow rate of the first electrospinning solution S1 is 1.6~4.8 mL / h, the spinning flow rate of the second electrospinning solution S2 is 0.2~1.6 mL / h, and the other parameters are the same: the positive and negative voltages are +10~+25 kV and -7~-10 kV, the receiving distance is 10~20 cm, the operating temperature is 20~40℃, the relative humidity is 30~75%, the inner diameter of the electrospinning needle is 0.5~0.8 mm, and the rotation speed of the receiving roller is 300~400 rpm.

[0032] In step (3), the nanofiber membrane is dried in an air atmosphere at a temperature of 100-140°C for 24-48 hours.

[0033] This invention also provides a polyarylene ether nitrile nanofiber membrane prepared by the above-described method, which has a uniform and stable porous structure. The nanofibers within the membrane fuse together through high-density bonding points formed in situ at their intersections, forming an integrated three-dimensional / two-dimensional network. The bonding point density ranges from 500 to 800 points / mm². 2 The areal density of the polyarylene ether nitrile nanofiber membrane is 1.0 × 10⁻⁶. -3 ~2.0×10 -3 g / cm 2 .

[0034] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0036] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. These other embodiments are also covered within the scope of protection of this invention.

[0037] Example 1: 2 g of polyarylene ether nitrile was added to 8 g of tetrahydrofuran and stirred thoroughly at room temperature to fully dissolve the polyarylene ether nitrile, thus obtaining the first electrospinning solution S1.

[0038] 2 g of polyarylene ether nitrile was added to 8 g of N-methylpyrrolidone and stirred thoroughly at room temperature to fully dissolve the polyarylene ether nitrile, thus obtaining the second electrospinning solution S2.

[0039] Electrospinning solutions S1 and S2 were respectively loaded into two independent electrospinning syringes and electrospinned on the same dual-channel electrospinning machine. The inner diameter of the spinning needles was 0.5 mm, the spinning distance was 15 cm, the spinning voltage at the needles was +20 kV, and the spinning voltage at the rollers was -10 kV. The feed rate of the syringe containing the first electrospinning solution S1 was 1.6 mL / h, and the feed rate of the syringe containing the second electrospinning solution S2 was 0.2 mL / h. The temperature was 25℃, the relative humidity was 45%, and the receiving roller speed was 400 rpm.

[0040] The spun nanofiber membrane was dried in a drying oven at 140℃ for 24 h. Residual solvent was removed from the membrane, yielding a membrane with an areal density of 0.002 g / cm³. 2 Nanofiber membranes with a high-density bonding point network.

[0041] The SEM image of the polyaryletheronitrile nanofiber membrane prepared in this embodiment is shown below. Figure 2-3 As shown, the fiber surface is relatively smooth, and the internal nanofibers fuse together through high-density bonding points formed in situ at the intersections to form an integrated three-dimensional / two-dimensional network with a uniformly distributed pore structure.

[0042] Example 2: 1.8 g of polyarylene ether nitrile was added to 8.2 g of acetone and stirred thoroughly at room temperature to fully dissolve the polyarylene ether nitrile, thus obtaining the first electrospinning solution S1.

[0043] 1.8 g of polyarylene ether nitrile was added to 8.2 g of N-methylpyrrolidone and stirred thoroughly at room temperature to fully dissolve the polyarylene ether nitrile, thus obtaining the second electrospinning solution S2.

[0044] Two electrospinning solutions, S1 and S2, were respectively loaded into two independent electrospinning syringes and electrospinned on the same dual-channel electrospinning machine. The inner diameter of the spinning needles was 0.6 mm, the spinning distance was 20 cm, the spinning voltage at the needles was +18 kV, and the spinning voltage at the rollers was -9.5 kV. The feed rate of the syringe containing the first electrospinning solution S1 was 2 mL / h, and the feed rate of the syringe containing the second electrospinning solution S2 was 1 mL / h. The spinning environment temperature was 30℃, the relative humidity was 40%, and the receiving roller speed was 300 rpm.

[0045] The spun nanofiber membrane was dried in a drying oven at 125℃ for 28 h. Residual solvent was removed from the membrane, yielding a membrane with an areal density of 0.0016 g / cm³. 2 Nanofiber membranes with a high-density bonding point network.

[0046] Example 3: 1.6 g of polyarylene ether nitrile was added to 8.4 g of tetrahydrofuran and stirred thoroughly at room temperature to fully dissolve the polyarylene ether nitrile, thus obtaining the first electrospinning solution S1.

[0047] 1.6 g of polyarylene ether nitrile was added to 8.4 g of dihydro-L-glucosamine and stirred thoroughly at room temperature to fully dissolve the polyarylene ether nitrile, thus obtaining the second electrospinning solution S2.

[0048] Two electrospinning solutions, S1 and S2, were respectively loaded into two independent electrospinning syringes and electrospinned on the same dual-channel electrospinning machine. The inner diameter of the spinning needles was 0.72 mm, the spinning distance was 25 cm, the spinning voltage at the needles was +25 kV, and the spinning voltage at the rollers was -10.5 kV. The feed rate of the syringe containing the first electrospinning solution S1 was 3 mL / h, and the feed rate of the syringe containing the second electrospinning solution S2 was 1.4 mL / h. The spinning environment temperature was 30℃, the relative humidity was 35%, and the receiving roller speed was 360 rpm.

[0049] The spun nanofiber membrane was dried in a drying oven at 100℃ for 48 h. Residual solvent was removed from the membrane, yielding a membrane with an areal density of 0.001 g / cm³. 2 A nanofiber membrane with a high-density bonding point network.

[0050] The nanocellulose membranes prepared in Examples 1-3 were analyzed using scanning electron microscopy. The number of visible bonding morphologies at fiber intersections per unit area was counted to obtain the bonding point density, and their mechanical properties were tested. The stress-strain curves are shown below. Figure 4 As shown, the fracture elongation, fracture stress, tensile strength, and elastic modulus were extracted from the data, and the results are summarized in Table 1: Table 1. Structure and mechanical properties of polyarylether nitrile nanofiber membranes prepared in the examples.

[0051] The experimental data above clearly show that as the surface density of the polyarylene ether nitrile nanofiber membrane increases, from 0.0010 g / cm³ in Example 3, the density of the membrane decreases. 2 Increased to 0.0020 g / cm³ in Example 1. 2The density of bonding points between fibers within the membrane increases accordingly, resulting in a significant and systematic enhancement of its mechanical properties. Specifically, tensile strength increases from 1.614 MPa to 4.470 MPa, and elastic modulus increases substantially from 24.188 MPa to 163.623 MPa, confirming that the structural rigidity and load-bearing capacity of the fiber network increase synchronously with the increase in bonding point density. Although the elongation at break is adjusted, the significant upward trend in the core mechanical indicators of fracture stress, tensile strength, and elastic modulus fully demonstrates that this invention, through the in-situ formation of a high-density bonding point network, achieves an effective and controllable improvement in the mechanical properties of the membrane without sacrificing the morphology and porous structure of the nanofibers.

[0052] Therefore, this invention discloses a polyarylene ether nitrile nanofiber membrane and its preparation method by dual solvent synergistic electrospinning, which solves the problem of loose structure caused by weak interfiber bonding in existing polyarylene ether nitrile nanofiber membranes. It not only simplifies the process, but also fundamentally improves the structural controllability and performance repeatability of the product.

[0053] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and does not limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing polyarylether nitrile nanofiber membranes by dual-solvent synergistic electrospinning, characterized in that, Includes the following steps: (1) Preparation of dual-solvent electrospinning solution: Polyarylene ether nitrile was dissolved in a high-volatility solvent system and a low-volatility solvent system with different solubility and compatibility parameters to obtain two electrospinning solutions with different properties, namely, the first electrospinning solution S1 and the second electrospinning solution S2. (2) Preparation of self-densified nanofiber membrane: Using dual-channel synergistic electrospinning, the first electrospinning solution S1 and the second electrospinning solution S2 prepared in step (1) are loaded into independent spinning channels and spun, so that the polyarylene ether nitrile fibers formed are alternately deposited on the same collection device to construct a nanofiber membrane with an in-situ bonding point network at the fiber intersection. (3) Drying and structural stabilization: The nanofiber membrane is dried to remove residual solvent and fix its internal bonding network to obtain a polyarylether nitrile nanofiber membrane with a high density bonding network.

2. The method for preparing a polyarylene ether nitrile nanofiber membrane by dual-solvent synergistic electrospinning according to claim 1, characterized in that, In step (1), the polyarylene ether nitrile is phenolphthalein type polyarylene ether nitrile or bisphenol A type polyarylene ether nitrile, with a weight average molecular weight of 80,000~120,000.

3. The method for preparing a polyarylene ether nitrile nanofiber membrane by dual-solvent synergistic electrospinning according to claim 2, characterized in that, In step (1), the mass fraction of solute in the first electrospinning solution S1 and the second electrospinning solution S2 is the same, both being 16~20%.

4. The method for preparing a polyarylene ether nitrile nanofiber membrane by dual-solvent synergistic electrospinning according to claim 2, characterized in that, In step (1), the saturated vapor pressure of the solvent in the high-volatility system at 25°C ranges from 10 to 20 kPa, and the Hansen solubility parameter δ T 18~20 MPa 1 / 2 ; The saturated vapor pressure of the low-volatility solvent system at 25°C ranges from 10 to 100 Pa, and the Hansen solubility parameter δ... T 21~23 MPa 1 / 2 .

5. The method for preparing a polyarylene ether nitrile nanofiber membrane by dual-solvent synergistic electrospinning according to claim 1, characterized in that, In step (1), the solvent for the high-volatility system is either tetrahydrofuran or acetone, and the solvent for the low-volatility system is either N-methylpyrrolidone or dihydrol-glucanone.

6. The method for preparing a polyarylene ether nitrile nanofiber membrane by dual-solvent synergistic electrospinning according to claim 1, characterized in that, In step (2), the spinning flow rate of the first electrospinning solution S1 is 1.6~4.8 mL / h, the positive and negative voltages are +10~+25 kV and -7~-10 kV respectively, the receiving distance is 10~20 cm, the operating temperature is 20~40℃, the relative humidity of the environment is 30~75%, the inner diameter of the electrospinning needle is 0.5~0.8 mm, and the rotation speed of the receiving roller is 300~400 rpm.

7. The method for preparing a polyarylene ether nitrile nanofiber membrane by dual-solvent synergistic electrospinning according to claim 1, characterized in that, In step (2), the spinning flow rate of the second electrospinning solution S2 is 0.2~1.6 mL / h, the positive and negative voltages are +10~+25 kV and -7~-10 kV respectively, the receiving distance is 10~20 cm, the operating temperature is 20~40℃, the relative humidity of the environment is 30~75%, the inner diameter of the electrospinning needle is 0.5~0.8 mm, and the rotation speed of the receiving roller is 300~400 rpm.

8. The method for preparing a polyarylene ether nitrile nanofiber membrane by dual-solvent synergistic electrospinning according to claim 1, characterized in that, In step (3), the nanofiber membrane is dried in an air atmosphere at a temperature of 100-140°C for 24-48 hours.

9. A polyarylether nitrile nanofiber membrane, characterized in that, The polyarylene ether nitrile nanofiber membrane prepared by any one of claims 1-8 has a uniform and stable porous structure, and the nanofibers inside it fuse together through high-density bonding points formed in situ at the intersections to form an integrated three-dimensional / two-dimensional network.

10. A polyarylene ether nitrile nanofiber membrane according to claim 9, characterized in that, The density of adhesive joints ranges from 500 to 800 per mm. 2 The areal density of the polyarylene ether nitrile nanofiber membrane is 1.0 × 10⁻⁶. -3 ~2.0×10 -3 g / cm 2 .

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