Preparation method for multilayer reinforced alkali-water composite separator

Abstract

Provided in the present invention is a preparation method for a multilayer reinforced alkali-water composite separator, comprising the following steps: step S1: preparing raw materials, the raw materials comprising polysulfone, zirconium dioxide, polyethylene glycol, polyvinylpyrrolidone, potassium chloride, methylpyrrolidone and a PEEK woven mesh; step S2: preparing a slurry; and step S3: preparing a separator. The present invention has the following beneficial effects: a PEEK woven mesh is used as a reinforced skeleton layer, the melting point of a PEEK material is 340°C, while the melting point of pps is about 280°C, such that the heat resistance of the PEEK material is significantly higher than that of a pps mesh cloth, and for future application in high-temperature alkaline electrolytic cells (>100°C), the heat resistance and safety of separators are greatly improved.

Description

Preparation method of multilayer reinforced alkaline water composite diaphragm TECHNICAL FIELD

[0001] The present application relates to the technical field of composite diaphragm preparation methods, and particularly relates to a preparation method of a multilayer reinforced alkaline water composite diaphragm. BACKGROUND

[0002] At present, hydrogen produced by mature and low-cost fossil energy is still the main hydrogen supplier in the early stage of the development of China's hydrogen energy industry, and industrial by-product hydrogen is used as a transitional hydrogen source with low cost in the medium term, and plays a supplementary role in the market. In the long term, hydrogen produced by renewable energy electrolysis, which is cleaner and more efficient, will gradually expand its share and replace hydrogen produced by fossil energy to become the main hydrogen supplier in the market.

[0003] According to the working principle and electrolyte, water electrolysis hydrogen production technology can be divided into four types: alkaline water electrolysis (ALK), proton exchange membrane water electrolysis (PEM), high-temperature solid oxide water electrolysis (SOEC) and anion exchange membrane water electrolysis (AEM). The mainstream technology route is the alkaline water electrolysis equipment (ALK) technology, which has completed the commercialization process and occupies the dominant position in the market. The PEM technology is still in the early stage of commercialization due to its high cost, and the SOEC and AEM technologies are still in the research and development stage.

[0004] Diaphragm material is an important component of alkaline electrolysis tank, and its main functions include three aspects: ① separating cathode and anode to form cathode and anode chambers to prevent short circuit; ② preventing mixing of gas products from two poles; ③ having high ion conductivity to facilitate the transfer of hydroxyl ions from the cathode to the anode. Therefore, an ideal diaphragm material should have the following characteristics: ① good ion conductivity, high porosity and low resistivity; ② high gas barrier property, high hydrophilicity and high corrosion resistance; ③ thin thickness, small pore size, high mechanical strength and good dimensional stability; ④ low cost and long service life. The quality of the diaphragm directly affects the purity of H2 and O2 and the power consumption.

[0005] The third-generation organic-inorganic composite diaphragm is a hot research topic at home and abroad. This composite diaphragm is composed of a pps base coated with slurry on both sides. For example, the ZIRFON product of Agfa contains zirconium dioxide and polymers in the surface coating slurry. The inorganic oxide nanoparticles such as zirconium dioxide are the main substances for improving the hydrophilicity of the diaphragm. The mechanism of improving hydrophilicity may be that the oxygen ions in zirconium dioxide form hydrogen bonds with water in the electrolyte. Therefore, the main purpose of surface coating is to improve the hydrophilicity of the diaphragm, improve the compatibility of the diaphragm with the electrolyte, and reduce the internal resistance of the electrolysis tank. However, the mechanical strength and heat resistance of the composite diaphragm supported by the pps mesh are relatively weak, and it is easy to crack and burst during the assembly of the electrolysis tank. Long-term immersion and corrosion in high-concentration potassium hydroxide solution quickly deteriorate the physical and chemical properties of the diaphragm, causing the coating to fall off, gas leakage between the cathode and anode, and explosion hazards in the electrolysis tank. SUMMARY

[0006] In order to overcome the above problems in the prior art, the present application provides a preparation method of a multi-layer reinforced alkaline water composite diaphragm.

[0007] The present application discloses a preparation method of a multi-layer reinforced alkaline water composite diaphragm, comprising the following steps:

[0008] Step S1: raw material preparation; the raw materials include polysulfone, zirconium dioxide, polyethylene glycol, polyvinylpyrrolidone, potassium chloride, methylpyrrolidone and PEEK woven net;

[0009] Step S2: slurry preparation;

[0010] Step S3: film preparation.

[0011] On this basis, the ratio of polysulfone to zirconium dioxide is 1:3-5.

[0012] On this basis, the ratio of polysulfone to polyethylene glycol is 1:0.2-1.

[0013] On this basis, the ratio of polysulfone to polyvinylpyrrolidone is 1:0.2-0.5.

[0014] On this basis, the ratio of polysulfone to potassium chloride is 1:0.01-0.08.

[0015] On this basis, the ratio of polysulfone to methylpyrrolidone is 1:4-8.

[0016] On this basis, the thickness of the PEEK is 30-80 μm.

[0017] On this basis, the slurry preparation method of step 2 comprises the following steps:

[0018] Step S21: heat and disperse polysulfone in methylpyrrolidone at 60-100°C to obtain a uniform transparent polymer solution;

[0019] Step S22: add zirconium oxide, disperse at a high speed of 500-1500 r / min for 2-8 h, then add polyethylene glycol, polyvinylpyrrolidone and potassium chloride in sequence, continue to stir at 200-600 r / min for 2-8 h;

[0020] Step S23: after the solution forms a homogeneous system, vacuum degassing for 3-8 h to obtain a milky white slurry.

[0021] On this basis, the film preparation method of step S3 comprises the following steps:

[0022] Step S31: The release PET back film is pulled out from the unwinding mechanism, changes the film direction through the guide roller, and then enters the slurry coating unit;

[0023] Step S32: The release film is coated with slurry at the back roller of the slurry coating unit. The slurry is transported from the transfer tank to the extrusion die through the pipeline by the screw pump, and a layer of slurry is scraped on the back film.

[0024] Step S33: The film strip advances to the pressure roller mechanism, and the PEEK mesh is pre-stuck with the wet slurry coated on the bottom.

[0025] Step S34: The film strip advances to the extrusion die, and the wet slurry is scraped on the PEEK mesh through the screw pump to a thickness of 80 microns.

[0026] Step S35: The film strip continues to advance directly into the coagulation bath unit, and the wet slurry film undergoes phase transition in it. After 5-20 minutes, the final cured organic-inorganic composite film is formed.

[0027] On this basis, the coagulation bath unit in step S35 is kept at a constant temperature.

[0028] Compared with the prior art, the beneficial effects of the present application are:

[0029] (1) PEEK woven mesh is used as the reinforcing skeleton layer. The melting point of PEEK material is 340℃, while the melting point of pps is about 280℃. The heat resistance of PEEK material is significantly higher than that of pps mesh. In the future, for high-temperature alkaline electrolytic cells (>100℃), the heat resistance and safety of the diaphragm are greatly improved.

[0030] (2) PEEK material has higher hydrophilicity than pps material. The carbon group on the main chain has greater polarity, and it is easy to form physical combination with ceramic powder, improving the adhesion of ceramic powder and the base material.

[0031] (3) The thickness of PEEK woven mesh for electrolytic cells is 50-200 microns, and the opening rate is 40-75%. The innovative PEEK woven mesh multi-layer reinforced composite technology prepares a composite diaphragm. Compared with single-layer pps alkaline composite diaphragm, the tensile strength, ion permeability, surface resistance, and puncture strength are significantly improved. The thickness can be made thinner, reducing the cost of the diaphragm, and improving the electrochemical performance and safety and reliability.

[0032] (4) This technology realizes batch production of at least 2 layers of reinforced skeleton composite film, and the product performance is better than that of similar products on the market. The molecular weight of the resin used for PEEK mesh weaving is 8-12 million, and the thickness of the multi-layer reinforced composite film is 150-500 microns. BRIEF DESCRIPTION OF DRAWINGS

[0033] Fig. 1 is a structural schematic diagram of the multi-layer reinforced net coating film area process of the present application;

[0034] Fig. 2 is a structural schematic diagram of the PEEK reinforced net layer of the present application;

[0035] Fig. 3 is a structural schematic diagram of the surface SEM of the composite diaphragm;

[0036] Fig. 4 is a structural schematic diagram of the cross-section SEM of the composite diaphragm;

[0037] In the figure: 1, unwinding mechanism, 2, guide roller, 3, slurry coating unit, 4, coagulation bath unit, 11, first extrusion die, 12, first compression roller mechanism, 13, second extrusion die, 14, second compression roller mechanism, 15, third extrusion die, 16, third compression roller mechanism, 17, fourth extrusion die, 18, fourth compression roller mechanism, 19, fifth extrusion die, 20, fifth compression roller mechanism, 21, sixth extrusion die. DETAILED DESCRIPTION

[0038] The present application will be further described in detail below in combination with the accompanying drawings and examples. It should be understood that the specific examples described herein are intended to explain the present application, and are not intended to limit the present application.

[0039] The present application discloses a preparation method of a multi-layer reinforced alkali water composite diaphragm, comprising the following steps:

[0040] Step S1: raw material preparation; the raw materials include polysulfone, zirconium dioxide, polyethylene glycol, polyvinylpyrrolidone, potassium chloride, methylpyrrolidone and PEEK woven net, the ratio of polysulfone to zirconium dioxide is 1:3-5; the ratio of polysulfone to polyethylene glycol is 1:0.2-1; the ratio of polysulfone to polyvinylpyrrolidone is 1:0.2-0.5; the ratio of polysulfone to potassium chloride is 1:0.01-0.08; the ratio of polysulfone to methylpyrrolidone is 1:4-8; referring to Fig. 2, the thickness of PEEK is 30-80 μm;

[0041] Step S2: slurry preparation; specifically: step S21: heat and disperse polysulfone to dissolve in methylpyrrolidone at 60-100 ℃ to obtain a uniform transparent polymer solution; step S22: add zirconium dioxide, disperse at a high speed of 500-1500 r / min for 2-8 h, then add polyethylene glycol, polyvinylpyrrolidone and potassium chloride in sequence, continue to stir at 200-600 r / min for 2-8 h; step S23: after the solution forms a homogeneous system, vacuum degassing for 3-8 h to obtain a milky white slurry.

[0042] Step S3: film making, specifically: step S31: the release PET back film is drawn out from the unwinding mechanism 1, changes the film direction after passing through the guide roller 2, and enters the slurry coating unit 3; step S32: the release film is at the first back roller of the slurry coating unit, and the slurry is transported to the extrusion die by the screw pump, so that the slurry in the transfer tank is delivered to the extrusion die by the pipeline, and a layer of slurry is scraped on the back film; step S33: the film strip advances to the pressure roller mechanism, and the PEEK mesh is pre-stuck with the wet slurry of the primer by the pressure roller mechanism; step S34: the film strip advances to the extrusion die, and the wet slurry is delivered to the extrusion die by the screw pump, so that a layer of wet slurry with a thickness of 80μm is scraped on the PEEK mesh; step S35: the film strip continues to advance and directly enters the coagulation bath unit 4, the coagulation bath unit 4 keeps the constant temperature, and the wet slurry film inside it undergoes phase transition, and after 5~20min, the cured organic-inorganic composite film is finally formed.

[0043] The prepared composite diaphragm structure is shown in Fig. 4.

[0044] Example 1

[0045] Raw material preparation: polysulfone 1 part, (D50, 0.5μm) zirconium dioxide 3 parts, polyethylene glycol 0.5 parts, polyvinylpyrrolidone 0.2 parts, potassium chloride 0.05 parts, methylpyrrolidone 6 parts and 50μm thick PEEK woven mesh;

[0046] Slurry preparation: at 80℃, heat 1 part of polysulfone to dissolve in 6 parts of methylpyrrolidone to obtain a uniform transparent polymer solution, add 3 parts of zirconium oxide, disperse at 800r / min for 3h, then add 0.5 parts of polyethylene glycol, 0.2 parts of polyvinylpyrrolidone and 0.01 parts of potassium chloride in turn, continue to stir at 400r / min for 3h, after the solution forms a homogeneous system, vacuum degassing for 6h to obtain a milky white slurry;

[0047] The film forming method is shown in Figure 1. The release PET backing film is drawn from the unwinding mechanism 1, changes the film direction through the guide roller 2, enters the slurry coating unit 3, and the slurry is transported to the first extrusion die 11 through the pipeline by the screw pump. A layer of wet slurry with a thickness of 80 μm is scraped on the backing film. The film strip advances to the first pressure roller mechanism 12, and the PEEK mesh is pre-stuck with the wet slurry on the bottom coating through the first pressure roller mechanism 12. The film strip advances to the second extrusion die 13, and a layer of wet slurry with a thickness of 80 μm is scraped on the PEEK mesh through the screw pump. The film strip advances to the second pressure roller mechanism 14, and the PEEK mesh is pre-stuck with the wet slurry on the PEEK mesh through the second pressure roller mechanism 14. The film strip advances to the third extrusion die 15, and a layer of wet slurry with a thickness of 70 μm is scraped on the PEEK mesh through the screw pump. The film strip continues to advance directly into the coagulation bath unit 4. The coagulation bath unit 4 maintains a constant temperature, and the wet slurry film undergoes phase transition inside. After 8-20 minutes, the final cured organic-inorganic composite film HQT1 is formed.

[0048] Example 2

[0049] Example 2 is different from Example 1 in that the release PET backing film is drawn from the unwinding mechanism 1, changes the film direction through the guide roller 2, enters the slurry coating unit 3, and the slurry is transported to the first extrusion die 11 through the pipeline by the screw pump. A layer of wet slurry with a thickness of 90 μm is scraped on the backing film. The film strip advances to the first pressure roller mechanism 12, and the PEEK mesh is pre-stuck with the wet slurry on the bottom coating through the first pressure roller mechanism 12. The film strip advances to the second extrusion die 13, and a layer of wet slurry with a thickness of 90 μm is scraped on the PEEK mesh through the screw pump. The film strip advances to the second pressure roller mechanism 14, and the PEEK mesh is pre-stuck with the wet slurry on the PEEK mesh through the second pressure roller mechanism 14. The film strip advances to the third extrusion die 15, and a layer of wet slurry with a thickness of 80 μm is scraped on the PEEK mesh through the screw pump. The film strip advances to the third pressure roller mechanism 16, and the PEEK mesh is pre-stuck with the wet slurry on the PEEK mesh through the third pressure roller mechanism 16. The film strip advances to the fourth extrusion die 17, and a layer of wet slurry with a thickness of 80 μm is scraped on the PEEK mesh through the screw pump. The film strip continues to advance directly into the coagulation bath unit 4, which maintains a constant temperature. The wet slurry film undergoes phase transition inside. After 9 minutes, the final cured organic-inorganic composite film HQT2 is formed.

[0050] Example 3

[0051] Example 3 differs from Example 1 in that the release PET backing film is drawn from the unwinding mechanism 1, changes the film direction after passing through the guide roller 2, and enters the slurry coating unit 3. The release film is at the first backing roller of the slurry coating unit 3. The slurry is transported from the transfer tank to the first extrusion die 11 by a pipe line through a screw pump, and is scraped on the backing film to form a layer of wet slurry with a thickness of 90 μm. The film strip advances to the first pressure roller mechanism 12, and the PEEK mesh is pre-stuck to the wet slurry of the base coating after passing through the first pressure roller mechanism 12. The film strip advances to the second extrusion die 13, and the wet slurry with a thickness of 80 μm is scraped on the PEEK mesh after passing through the screw pump. The film strip advances to the second pressure roller mechanism 14, and the PEEK mesh is pre-stuck to the wet slurry with the PEEK mesh after passing through the second pressure roller mechanism 14. The film strip advances to the third extrusion die 15, and the wet slurry with a thickness of 80 μm is scraped on the PEEK mesh after passing through the screw pump. The film strip advances to the third pressure roller mechanism 16, and the PEEK mesh is pre-stuck to the wet slurry with the PEEK mesh after passing through the third pressure roller mechanism 16. The film strip advances to the fourth extrusion die 17, and the wet slurry with a thickness of 85 μm is scraped on the PEEK mesh after passing through the screw pump. The film strip advances to the fourth pressure roller mechanism 18, and the PEEK mesh is pre-stuck to the wet slurry with the PEEK mesh after passing through the fourth pressure roller mechanism 18. The film strip advances to the fifth extrusion die 19, and the wet slurry with a thickness of 85 μm is scraped on the PEEK mesh after passing through the screw pump. The film strip continues to advance and directly enters the solidification bath unit 4, which maintains a constant temperature. The wet slurry film undergoes phase transition in the unit, and after 11 min, the final cured organic-inorganic composite film HQT3 is formed.

[0052] Example 4

[0053] Example 4 differs from Example 1 in that the release PET backing film is drawn from the unwinding mechanism 1, after changing the film direction by the guide roller 2, it enters the slurry coating unit 3. The release film is coated with slurry at the first backing roller of the slurry coating unit 3. The slurry is transported from the transfer tank to the first extrusion die 11 by a pipe line through a screw pump, and a layer of wet slurry with a thickness of 100 pm is scraped on the backing film. The film strip advances to the first pressure roller mechanism 12, and the PEEK mesh is pre-stuck to the wet slurry with the first pressure roller mechanism 12. The film strip advances to the second extrusion die 13, and a layer of wet slurry with a thickness of 90 pm is scraped on the PEEK mesh through a screw pump. The film strip advances to the second pressure roller mechanism 14, and the PEEK mesh is pre-stuck to the wet slurry with the second pressure roller mechanism 14. The film strip advances to the third extrusion die 15, and a layer of wet slurry with a thickness of 80 pm is scraped on the PEEK mesh through a screw pump. The film strip advances to the third pressure roller mechanism 16, and the PEEK mesh is pre-stuck to the wet slurry with the third pressure roller mechanism 16. The film strip advances to the fourth extrusion die 17, and a layer of wet slurry with a thickness of 90 pm is scraped on the PEEK mesh through a screw pump. The film strip advances to the fourth pressure roller mechanism 18, and the PEEK mesh is pre-stuck to the wet slurry with the fourth pressure roller mechanism 18. The film strip advances to the fifth extrusion die 19, and a layer of wet slurry with a thickness of 70 pm is scraped on the PEEK mesh through a screw pump. The film strip advances to the fifth pressure roller mechanism 20, and the PEEK mesh is pre-stuck to the wet slurry with the fifth pressure roller mechanism 20. The film strip advances to the sixth extrusion die 21, and a layer of wet slurry with a thickness of 30 pm is scraped on the PEEK mesh through a screw pump. The film strip continues to advance and directly enters the solidification bath unit 4, which maintains a constant temperature. The wet slurry film undergoes phase transition in the unit, and after 11 min, the final cured organic-inorganic composite film HQT4 is formed.

[0054] Example 5

[0055] Example 5 differs from Example 1 in that the release PET backing film is drawn from the unwinding mechanism 1, changes the film direction after passing through the guide roller 2, and enters the slurry coating unit 3. The release film is at the first backing roller of the slurry coating unit 3. The slurry is transported from the transfer tank to the first extrusion die 11 by a pipe line through a screw pump, and is scraped on the backing film to form a layer of wet slurry with a thickness of 80 pm. The film strip advances to the first pressure roller mechanism 12, and the PEEK mesh is pre-stuck to the wet slurry of the base coating after passing through the first pressure roller mechanism 12. The film strip advances to the second extrusion die 13, and the wet slurry with a thickness of 80 pm is scraped on the PEEK mesh after passing through the screw pump. The film strip advances to the second pressure roller mechanism 14, and the PEEK mesh is pre-stuck to the wet slurry with the PEEK mesh after passing through the third pressure roller mechanism 14. The film strip advances to the third extrusion die 15, and the wet slurry with a thickness of 70 pm is scraped on the PEEK mesh after passing through the screw pump. The film strip continues to advance and directly enters the coagulation bath unit 4, which maintains a constant temperature. The wet slurry film undergoes phase transition in the unit, and after 10 min, the final cured organic-inorganic composite film HQT5 is formed.

[0056] Comparative Example 1

[0057] Raw material preparation: 1 part of polysulfone, 3 parts of zirconium dioxide (D50, 0.5 pm), 0.5 parts of polyethylene glycol, 0.2 parts of polyvinylpyrrolidone, 0.01 parts of potassium chloride, 6 parts of methylpyrrolidone, and a 50 pm thick pps woven mesh;

[0058] Slurry preparation: 1 part of polysulfone is heated and dispersed to dissolve in 6 parts of methylpyrrolidone at 80°C to obtain a uniform transparent polymer solution. 3 parts of zirconium dioxide are added and dispersed at 800 r / min for 3 h. Then 0.5 parts of polyethylene glycol, 0.2 parts of polyvinylpyrrolidone, and 0.01 parts of potassium chloride are added in sequence, and continue to stir at 400 r / min for 3 h. After the solution forms a homogeneous system, vacuum degassing is performed for 6 h to obtain a milky white slurry;

[0059] The film forming method is shown in Figure 1. The release PET back film is drawn from the unwinding mechanism 1, changes the film direction through the guide roller 2, enters the slurry coating unit 3, and the release film is coated with a layer of wet slurry with a thickness of 120 μm at the first back roller of the slurry coating unit 3. The slurry is transported to the first extrusion die 11 by the screw pump, and then scraped on the back film to form a layer of wet slurry with a thickness of 120 μm. The film strip advances to the first pressure roller mechanism 12, and the pps mesh is pre-stuck with the wet slurry of the primer through the first pressure roller mechanism 12. The film strip advances to the second extrusion die 13, and a layer of wet slurry with a thickness of 95 μm is scraped on the pps mesh through the screw pump. The film strip continues to advance directly into the coagulation bath unit 4, which maintains a constant temperature. The wet slurry film undergoes phase transition in the unit, and after 8 min, the final cured organic-inorganic composite film PQT1 is formed after 5-20 min.

[0060] The properties are shown in Table 1 below:

[0061] Product Reinforced Type Separator Thickness (μm) Porosity (%) Alkali Absorption Rate (%) Alkali Resistance Loss Rate (%) Tensile Strength MPa Contact Angle (°) Surface Resistance Ω·cm 2 Bubble Point Pressure bar Maximum Pore Size (Bubble Point Pore Size), Nanometer Electrolytic Water Test (90℃, 0.25A / cm 2 ) Working Voltage (V) Agfapps Single Layer 500 61.25 67.12 0.4342 0.8345 90.32 1.6727 3.61.86 HQT1 PEEK Two Layers 200 62.05 72.5 0.2343 2.4806 50.12 1.9427 9.31.74 HQT2 PEEK Three Layers 320 60.65 88.6 0.1343 6.7506 70.14 1.9826 3.51.76 HQT3 PEEK Four Layers 380 61.96 84.6 0.1342 0.9170 90.18 2.1625 6.41.78 HQT4 PEEK Five Layers 450 60.14 88.6 0.1195 5.8317 00.22 2.2222 62.21.81 HQT5 PEEK Two Layers 200 61.36 75.5 0.1343 3.5640.11.9427 8.81.72 PQT1 PPS Single Layer 200 59.54 77.3 0.1561 9.8550.35 1.8429 7.21.92

[0062] Table 1

[0063] In summary, the PEEK woven mesh is used as the reinforcing framework layer, the melting point of PEEK material is 340 DEG C, and the melting point of pps is about 280 DEG C, the heat resistance of PEEK material is significantly higher than that of pps mesh, and the heat resistance and safety of the diaphragm are greatly improved for the application of high-temperature alkaline electrolytic tank (> 100 DEG C);

[0064] Secondly, compared with pps material, PEEK material has higher hydrophilicity, and the polarity of carbon group on the main chain is larger, which is easy to form physical combination with ceramic powder, thereby improving the adhesion of ceramic powder and the base material,

[0065] The thickness of the PEEK woven mesh for the electrolytic tank is 50-200 mu m, and the opening rate is 40-75%. The innovative PEEK woven mesh multi-layer reinforcing composite technology is used to prepare a composite diaphragm, and compared with the single-layer pps alkaline composite diaphragm, the tensile strength, ion permeability, surface resistance and puncture strength are obviously improved, the thickness can be thinner, the cost of the diaphragm is reduced, and the electrochemical performance and safety reliability are improved;

[0066] The technology realizes batch preparation and production of at least 2 layers of reinforcing framework composite membrane, and the product performance is better than that of the same product on the market, wherein the resin molecular weight for the PEEK mesh preparation is 8-12 million, and the thickness of the multi-layer reinforcing composite membrane is 150-500 mu m.

[0067] The above description shows and describes the preferred embodiments of the present application, as previously described, it should be understood that the present application is not limited to the form disclosed herein, and should not be considered as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the inventive concept described herein by the above teaching or related art or knowledge. The modifications and changes made by those skilled in the art without departing from the spirit and scope of the present application shall be within the protection scope of the appended claims of the present application.

Claims

1. A method for producing a multilayer reinforced alkaline water composite separator, characterized by, It comprises the following steps: Step S1: raw material preparation; the raw material comprises polysulfone, zirconium dioxide, polyethylene glycol, polyvinylpyrrolidone, potassium chloride, methylpyrrolidone and PEEK woven net; Step S2: slurry preparation; Step S3: film preparation.

2. The method of claim 1, wherein the multilayer reinforced alkaline water composite separator is prepared by the steps of: The ratio of the polysulfone to the zirconium dioxide is 1:3-5.

3. The method of claim 2, wherein the multilayer reinforced alkaline water composite separator is prepared by the steps of: The ratio of the polysulfone to the polyethylene glycol is 1:0.2-1.

4. The method of claim 3, wherein the multilayer reinforced alkaline water composite separator is prepared by the steps of: The ratio of the polysulfone to the polyvinylpyrrolidone is 1:0.2-0.

5.

5. The method of claim 4, wherein the multilayer reinforced alkaline water composite separator is prepared by the steps of: The ratio of the polysulfone to the potassium chloride is 1:0.01-0.

08.

6. The method of claim 5, wherein the multilayer reinforced alkaline water composite separator is prepared by the steps of: The ratio of the polysulfone to the methylpyrrolidone is 1:4-8.

7. The method of claim 6, wherein the multilayer reinforced alkaline water composite separator is prepared by the steps of: The thickness of the PEEK is 30-80 μm.

8. The method of claim 1, wherein the multilayer reinforced alkaline water composite separator is prepared by the steps of: The slurry preparation method of the step 2 comprises the following steps: Step S21: heat and disperse the polysulfone to dissolve in the methylpyrrolidone at 60-100 ℃ to obtain a uniform transparent polymer solution; Step S22: add the zirconium dioxide, disperse at a high speed of 500-1500 r / min for 2-8 h, then add the polyethylene glycol, the polyvinylpyrrolidone and the potassium chloride in sequence, and continue to stir at 200-600 r / min for 2-8 h; Step S23: after the solution forms a homogeneous system, vacuum degassing for 3-8 h to obtain a milky white slurry.

9. The method of claim 1, wherein the multilayer reinforced alkaline water composite separator is prepared by the steps of: The film preparation method of the step S3 comprises the following steps: Step S31: the release PET back film is pulled out from the unwinding mechanism (1), changes the film direction through the guide roller (2), and then enters the slurry coating unit (3); Step S32: the release film is coated with a layer of slurry at the back roller of the slurry coating unit (3), the slurry is transported to the extrusion die through the pipeline of the screw pump, and the slurry in the transfer tank is scraped on the back film to form a layer of slurry; Step S33: the film strip advances to the pressure roller mechanism, and the PEEK woven cloth is pre-stuck with the wet slurry of the primer through the pressure roller mechanism; Step S34: the film strip advances to the extrusion die, the wet slurry is scraped on the PEEK woven cloth through the screw pump to form a layer of wet slurry with a thickness of 80 μm; Step S35: the film strip continues to advance and directly enters the coagulation bath unit (4), the wet slurry film undergoes phase transition in the coagulation bath unit (4), and after 5-20 min, the organic-inorganic composite film after solidification is finally formed.

10. The method of claim 9, wherein the multilayer reinforced alkaline water composite separator is prepared by the steps of: The coagulation bath unit (4) in the step S35 is kept at a constant temperature.

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