Alkaline electrolyzed water device sealing element and preparation method thereof

Abstract

The invention provides a sealing element of an alkaline water electrolysis device and a preparation method of the sealing element. The method comprises the following steps: S1, adding polytetrafluoroethylene into a solvent, and carrying out first stirring to obtain a first membrane solution; s2, adding an initiator into the first membrane liquid, and performing second stirring to obtain second membrane liquid; s3, adding perfluoropropyl vinyl ether into the second membrane liquid, and performing third stirring to obtain third membrane liquid; s4, adding an inorganic filler into the third membrane solution, and performing fourth stirring to obtain a fourth membrane solution; and S5, the fourth membrane liquid is subjected to tape casting treatment and sintering treatment in sequence, and the alkaline electrolyzed water device sealing element is obtained. According to the invention, polytetrafluoroethylene is used as a base material, perfluoropropyl vinyl ether is introduced to modify the base material, and an inorganic filler is used as an auxiliary material, so that the alkaline water electrolysis device sealing element which has good sealing performance, mechanical strength and creep resistance and also shows excellent strong alkali aging resistance is prepared.

Description

Technical Field

[0001] The invention relates to the field of hydrogen production by water electrolysis, and in particular to a sealing component of an alkaline water electrolysis device and a preparation method thereof. Background Art

[0002] Alkaline water electrolysis hydrogen production refers to the process of producing hydrogen by electrolysis of water in an alkaline electrolyte environment. The electrolyte is generally a 30% mass concentration KOH solution. The main body of the electrolyzer used for alkaline water electrolysis hydrogen production is assembled from end pressure plates, seals, plates, plates, diaphragms and other components. Among them, the function of the seal is to prevent the electrolyte solution, hydrogen and oxygen from leaking from the electrolyzer under the operating conditions of 30% KOH solution, 90°C and 1.6MPa. As the main component of the electrolyzer seal, the quality of its seal largely determines the quality of the electrolyzer chamber sealing and insulation performance, which directly affects the safety and reliability of the entire water electrolysis hydrogen production system.

[0003] The common materials used for existing seals are silicone, rubber, and polytetrafluoroethylene (PTFE). The application conditions of alkaline electrolysis water technology are strong alkali, high temperature, and high pressure. The above-mentioned existing seals are easy to deform under high pressure and easy to age under strong alkali and high temperature. At the same time, the existing seals also have the problems of low hardness and poor air and liquid sealing, which are difficult to meet the use requirements.

[0004] Based on this, how to provide a preparation method of an alkaline water electrolysis device seal to obtain an alkaline water electrolysis device seal having excellent sealing performance, good aging resistance and high mechanical properties is one of the important technical problems that need to be solved in this field. Summary of the invention

[0005] The main purpose of the present invention is to provide an alkaline water electrolysis device seal and a preparation method thereof, so as to solve the problem that the alkaline water electrolysis device seal in the prior art is difficult to have excellent sealing performance, good aging resistance and high mechanical properties at the same time.

[0006] In order to achieve the above-mentioned purpose, the first aspect of the present invention provides a method for preparing a seal of an alkaline water electrolysis device, comprising: step S1, adding polytetrafluoroethylene to a solvent, and obtaining a first membrane liquid through a first stirring; step S2, adding an initiator to the first membrane liquid, and obtaining a second membrane liquid through a second stirring; step S3, adding perfluoropropyl vinyl ether to the second membrane liquid, and obtaining a third membrane liquid through a third stirring; step S4, adding an inorganic filler to the third membrane liquid, and obtaining a fourth membrane liquid through a fourth stirring; step S5, sequentially subjecting the fourth membrane liquid to a casting treatment and a sintering treatment to obtain a seal of an alkaline water electrolysis device.

[0007] Furthermore, based on 100% by weight of polytetrafluoroethylene, the added amount of perfluoropropyl vinyl ether is 5% to 6%.

[0008] Further, the third stirring is performed at 55° C. to 60° C., and the stirring speed of the third stirring is 300 rpm to 350 rpm, and the time is 4 h to 5 h.

[0009] Furthermore, the solvent is selected from one or more of petroleum ether, hexane, diethyl ether and n-butanol, preferably petroleum ether; preferably, the solid content of the first membrane liquid is 20wt% to 25wt%.

[0010] Furthermore, based on 100% of the total weight of the first membrane liquid, the added amount of the initiator is 10% to 12%, and the initiator is barium sulfate and / or ammonium persulfate, preferably barium sulfate.

[0011] Furthermore, the first stirring is performed at 60°C to 65°C, and the stirring speed of the first stirring is 100rpm to 300rpm; the second stirring is performed at 80°C to 90°C, and after the initiator is completely dispersed in the first membrane liquid, stirring is continued for 5min to 10min.

[0012] Furthermore, based on the total weight of the third membrane liquid as 100%, the amount of inorganic filler added is 60% to 70%, and the inorganic filler is selected from one or more of zirconium oxide, silicon oxide and aluminum oxide, preferably zirconium oxide; preferably, after the fourth stirring, step S4 also includes degassing the fourth membrane liquid at a speed of 25rpm to 30rpm.

[0013] Furthermore, the casting speed of the casting process is 0.15 cm / min to 0.25 cm / min; the temperature of the sintering process is 300° C. to 400° C., and the sintering process is carried out under the protection of an inert gas, preferably N2.

[0014] The second aspect of the present invention provides a seal for an alkaline water electrolysis device, wherein the seal for an alkaline water electrolysis device is prepared by the above-mentioned method for preparing the seal for an alkaline water electrolysis device.

[0015] Furthermore, the tensile strength of the seal of the alkaline water electrolysis device is 18MPa to 21MPa, and the sealing performance is 2.5E-05Pa·m 3 / s~8.5E-05Pa·m 3 / s.

[0016] By applying the technical solution of the present invention, a preparation method with a simple process and the ability to be scaled up for mass production is adopted, polytetrafluoroethylene is used as a substrate, and it is modified by introducing perfluoropropyl vinyl ether, and an inorganic filler is used as an auxiliary, so as to prepare an alkaline water electrolysis device seal having good sealing performance, mechanical strength and creep resistance, and exhibiting excellent resistance to strong alkali aging, which can well meet its use requirements. DETAILED DESCRIPTION

[0017] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0018] As described in the background technology, the alkaline water electrolysis device seal in the prior art has the problem that it is difficult to have excellent sealing, good anti-aging and high mechanical properties at the same time. In order to solve the above technical problems, the first aspect of the present invention provides a method for preparing an alkaline water electrolysis device seal, including: step S1, adding polytetrafluoroethylene to a solvent, and obtaining a first membrane liquid through a first stirring; step S2, adding an initiator to the first membrane liquid, and obtaining a second membrane liquid through a second stirring; step S3, adding perfluoropropyl vinyl ether to the second membrane liquid, and obtaining a third membrane liquid through a third stirring; step S4, adding an inorganic filler to the third membrane liquid, and obtaining a fourth membrane liquid through a fourth stirring; step S5, the fourth membrane liquid is sequentially subjected to a casting process and a sintering process to obtain an alkaline water electrolysis device seal.

[0019] The present invention introduces perfluoropropyl vinyl ether (PPVE) into polytetrafluoroethylene (PTFE) with corrosion resistance and high temperature resistance to achieve PTFE modification, significantly improving the anti-aging ability of the seal with PPVE as the main polymer material. Inorganic fillers are simultaneously introduced during the preparation process to significantly improve its mechanical strength and wear resistance.

[0020] In particular, in the above-mentioned preparation process, strictly controlling the timing and order of adding each component involved in the reaction system can obtain a fourth membrane liquid with more uniform dispersion and excellent modification and curing reaction effects. Compared with the method of adding and mixing all components at once, the above-mentioned addition preparation method can more accurately control the progress of the modification reaction, effectively promote the recombination between the PPVE and PTFE main chains, and thus prepare an alkaline water electrolysis device seal with good comprehensive performance, especially excellent sealing performance.

[0021] In several typical implementations, the amount of perfluoropropyl vinyl ether added is 5% to 6% based on 100% weight of polytetrafluoroethylene. The inventors have optimized the amount of PPVE added as above after a large number of experiments and comprehensively considered the various properties of PPVE-modified PTFE, and found that the seal prepared by modification under this ratio not only has significantly improved mechanical strength and sealing, but also maintains good elasticity, so that it can be applied to more complex situations and has a longer service life.

[0022] Furthermore, in order to better promote the reaction of PPVE-modified PTFE to be more complete and obtain a modified PTFE resin with a more complete chain structure and better mechanical properties, the third stirring is preferably carried out at 55°C to 60°C, and the stirring speed of the third stirring is 300rpm to 350rpm, and the time is 4h to 5h. The alkaline water electrolysis device seal prepared under this condition has higher sealing performance and stronger anti-aging performance.

[0023] In several typical embodiments, the solvent is selected from one or more of petroleum ether, hexane, ether and n-butanol, preferably petroleum ether, so as to promote better dissolution of PTFE, and to obtain a more uniformly dispersed membrane liquid system when other components are subsequently added, thereby improving the sealing performance of the obtained alkaline water electrolysis device seal. At the same time, in order to further improve the uniformity of the dispersion of the membrane liquid system, promote the occurrence of the modification reaction, and obtain a seal with better comprehensive performance, the solid content of the first membrane liquid is preferably 20wt% to 25wt%.

[0024] In the reaction process of PPVE-modified PTFE, in order to more accurately control the progress of the reaction and also improve the compatibility of the components in the membrane liquid reaction system, thereby improving the dimensional accuracy, mechanical properties and sealing performance of the seal, it is preferred that the total weight of the first membrane liquid is 100%, the amount of initiator added is 10% to 12%, and the initiator is barium sulfate and / or ammonium sulfate, preferably barium sulfate.

[0025] In several typical embodiments, the first stirring of mixing PTFE and solvent is preferably carried out at 60°C to 65°C, and the stirring speed of the first stirring is 100rpm to 300rpm. This stirring condition for mixing can more effectively reduce the thermal decomposition of PTFE resin and improve the dispersion uniformity of the material, so that the prepared seal has more stable performance and improves its anti-aging properties. Preferably, the second stirring is carried out at 80°C to 90°C, and after the initiator is completely dispersed in the first membrane liquid, stirring is continued for 5min to 10min. Complete dispersion here means that the initiator particles are evenly distributed in the first membrane liquid, the distance between each initiator particle is maximized, and there is no agglomeration and the like. Under this condition, a more evenly dispersed second membrane liquid containing PTFE and initiator can be obtained, so that the subsequent reaction between PTFE and PPVE is more fully carried out, and an alkaline electrolysis water device seal with excellent mechanical properties and sealing properties is obtained.

[0026] Furthermore, based on the total weight of the third membrane liquid as 100%, the amount of inorganic filler added is 60% to 70%, and the inorganic filler is selected from one or more of zirconium oxide, silicon oxide and aluminum oxide, preferably zirconium oxide. The inventor has optimized the type and amount of inorganic filler through a large number of experiments in order to obtain an alkaline water electrolysis device seal with stronger hardness, higher tensile strength and better anti-aging performance. In several typical embodiments, in order to reduce the structural defects of the seal caused by the presence of bubbles in the membrane liquid, it is preferred that after the fourth stirring, step S4 also includes degassing the fourth membrane liquid at a speed of 25rpm to 30rpm, so as to obtain an alkaline water electrolysis device seal with better comprehensive performance and less prone to aging failure.

[0027] In several typical embodiments, the inventors have preferably selected a casting speed of 0.15 cm / min to 0.25 cm / min after a large number of experiments, so as to better adapt to the membrane liquid system containing PPVE-modified PTFE, improve the structural integrity of the obtained seal, and thus make it have better mechanical properties and stability in use. The preferred sintering temperature is 300°C to 400°C, and the sintering is carried out under the protection of an inert gas, preferably N2. The above sintering method, which has been selected by the inventors after a large number of experiments, can more effectively remove solvents and solidify materials, while inhibiting oxidation, thereby improving the oxidation resistance and aging resistance of the prepared alkaline water electrolysis device seal.

[0028] The second aspect of the present invention provides an alkaline water electrolysis device seal, which is prepared by the preparation method of the alkaline water electrolysis device seal. The obtained alkaline water electrolysis device seal has higher mechanical strength, higher creep resistance, more superior sealing and better aging resistance, and is also more wear-resistant and has better comprehensive performance. It can also perform well in extreme environments such as high temperature and high pressure, so as to meet the requirements of the application conditions of the alkaline water electrolysis device.

[0029] In several preferred embodiments, in order to better meet the requirements of the application environment of the alkaline water electrolysis device, the tensile strength of the alkaline water electrolysis device seal is preferably 18MPa to 21MPa, and the sealing performance is 2.5E-05Pa·m 3 / s~8.5E-05Pa·m 3 / s.

[0030] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0031] Unless otherwise defined, all professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0032] Example 1

[0033] A method for preparing a seal for an alkaline water electrolysis device:

[0034] 1) mixing PTFE resin and petroleum ether to dilute a polymer solution with a solid content of 20 wt.%, heating to 60° C., and stirring and mixing at a speed of 200 rpm to obtain a first membrane solution;

[0035] 2) adding barium sulfate in a ratio of 10 wt.% (compared to the mass of the first membrane liquid) slowly and step by step into the stirring tank containing the first membrane liquid, heating to 80° C. and stirring until all the barium sulfate is completely mixed into the first membrane liquid, and then continuing to stir for 10 minutes to obtain a second membrane liquid;

[0036] 3) adding 5 wt.% (compared to the mass of PTFE) of perfluoropropyl vinyl ether to the second membrane liquid, lowering the temperature to 60° C., stirring at a stirring speed of 300 rpm for 4 hours to obtain a third membrane liquid;

[0037] 4) Add 60wt.% (compared to the mass of the third membrane liquid) of zirconium oxide filler to the third membrane liquid, slowly add it to the stirring tank containing the third membrane liquid in multiple steps, mix them evenly to obtain the fourth membrane liquid, then adjust the rotation speed to 30rpm, slowly rotate to degas, and set aside.

[0038] 5) Pre-debug the casting equipment, set the die height to 2mm (the adjustable sheet can reach 0.3mm), the casting speed to 0.20cm / min, pour the stirred film liquid into the casting tank, start the casting machine, cast the film liquid at room temperature, heat the bottom plate to 100℃ for pre-evaporation, and set the evaporation time to 10min. Then put the semi-dry seal into an alcohol-water ratio of 1:6 to dissolve the volatile solvent and cure it;

[0039] 5) The processed semi-finished product is placed in a muffle furnace, heated to 350° C. in a N2 atmosphere, and sintered to obtain a seal for an alkaline water electrolysis device.

[0040] Example 2

[0041] A method for preparing a seal for an alkaline water electrolysis device:

[0042] The difference between this embodiment and embodiment 1 is only in step 3), specifically: 3 wt.% (compared to the mass of PTFE) of perfluoropropyl vinyl ether is added to the second membrane liquid, the temperature is lowered to 50° C., and the mixture is stirred at a stirring speed of 250 rpm for 3 hours to obtain a third membrane liquid. The remaining steps and conditions remain unchanged.

[0043] Example 3

[0044] A method for preparing a seal for an alkaline water electrolysis device:

[0045] The difference between this embodiment and embodiment 1 is only in step 3), specifically: add 8 wt.% (compared to the mass of PTFE) of perfluoropropyl vinyl ether to the second membrane liquid, reduce the temperature to 65°C, stir at a stirring speed of 400 rpm and a stirring time of 6 hours to obtain a third membrane liquid.

[0046] Example 4

[0047] A method for preparing a seal for an alkaline water electrolysis device:

[0048] The difference between this embodiment and embodiment 1 is only in step 1), specifically: PTFE resin is mixed and diluted with petroleum ether to form a polymer solution with a solid content of 15 wt.%, heated to 55°C, and fully stirred and mixed at a speed of 350 rpm to obtain a first membrane solution. The remaining steps and conditions remain unchanged.

[0049] Example 5

[0050] A method for preparing a seal for an alkaline water electrolysis device:

[0051] The difference between this embodiment and embodiment 1 is only in step 1), specifically: PTFE resin is mixed and diluted with petroleum ether to form a polymer solution with a solid content of 30 wt.%, heated to 70°C, and fully stirred and mixed at a speed of 50 rpm to obtain a first membrane solution. The remaining steps and conditions remain unchanged.

[0052] Example 6

[0053] A method for preparing a seal for an alkaline water electrolysis device:

[0054] The difference between this embodiment and embodiment 1 is only in step 2), specifically: barium sulfate is slowly added to the stirring tank containing the first membrane liquid in multiple steps at a ratio of 8 wt.% (compared to the mass of the first membrane liquid), heated to 95° C. and stirred, and the second membrane liquid is obtained after all the barium sulfate is completely mixed into the first membrane liquid. The other steps and conditions remain unchanged.

[0055] Example 7

[0056] A method for preparing a seal for an alkaline water electrolysis device:

[0057] The difference between this embodiment and embodiment 1 is only in step 2), specifically: barium sulfate is slowly added to the stirring tank containing the first membrane liquid in multiple steps at a ratio of 14wt.% (compared to the mass of the first membrane liquid), heated to 75°C and stirred until all the barium sulfate is completely mixed into the first membrane liquid, and then stirred for 15 minutes to obtain the second membrane liquid. The other steps and conditions remain unchanged.

[0058] Example 8

[0059] A method for preparing a seal for an alkaline water electrolysis device:

[0060] The difference between this embodiment and embodiment 1 is only in step 4), specifically: add 55wt.% (compared to the mass of the third membrane liquid) of zirconium oxide filler to the third membrane liquid, slowly add it to the stirring tank containing the third membrane liquid in multiple steps, mix them evenly to obtain the fourth membrane liquid, then adjust the rotation speed to 20rpm, slowly rotate to degas, and set aside. The other steps and conditions remain unchanged.

[0061] Example 9

[0062] A method for preparing a seal for an alkaline water electrolysis device:

[0063] The difference between this embodiment and embodiment 1 is only in step 4), specifically: add 75wt.% (compared to the mass of the third membrane liquid) of zirconium oxide filler to the third membrane liquid, slowly add it to the stirring tank containing the third membrane liquid in multiple steps, mix them evenly to obtain the fourth membrane liquid, then adjust the rotation speed to 35rpm, slowly rotate to degas, and set aside. The other steps and conditions remain unchanged.

[0064] Example 10

[0065] A method for preparing a seal for an alkaline water electrolysis device:

[0066] The only difference between this embodiment and embodiment 1 is that the fourth membrane liquid obtained in step 4) is not subjected to degassing treatment. The remaining steps and conditions remain unchanged.

[0067] Embodiment 11

[0068] A method for preparing a seal for an alkaline water electrolysis device:

[0069] The only difference between this embodiment and embodiment 1 is that the casting speed in step 4) is changed to 0.1 cm / min and the sintering temperature in step 5) is changed to 250° C. The other steps and conditions remain unchanged.

[0070] Example 12

[0071] A method for preparing a seal for an alkaline water electrolysis device:

[0072] The only difference between this embodiment and embodiment 1 is that the casting speed in step 4) is changed to 0.3 cm / min, the sintering temperature in step 5) is changed to 450° C., and the N2 protection treatment during the sintering process is removed. The other steps and conditions remain unchanged.

[0073] Comparative Example 1

[0074] The PTFE resin raw material without adding any other materials was directly used to prepare the alkaline water electrolysis device seal as a sample.

[0075] Comparative Example 2

[0076] The commercial PTFE gasket of Fluorine New Materials was directly used as the sample.

[0077] Comparative Example 3

[0078] A method for preparing a seal for an alkaline water electrolysis device:

[0079] The only difference between this comparative example and Example 1 is that PTFE, barium sulfate, PPVE and zirconium oxide are added into petroleum ether, mixed to obtain a membrane liquid, and then directly cast and subsequently treated.

[0080] Comparative Example 4

[0081] A method for preparing a seal for an alkaline water electrolysis device:

[0082] The only difference between this comparative example and Example 1 is that step 3) is not performed, but the second membrane liquid is directly used as the third membrane liquid for subsequent experiments, and finally a sealing sample containing no PPVE is obtained.

[0083] Comparative Example 5

[0084] A method for preparing a seal for an alkaline water electrolysis device:

[0085] The only difference between this comparative example and Example 1 is that PPVE is replaced by an equal weight of perfluorobutylene (PFB), and finally a sealing member sample containing no PPVE but containing PFB is obtained.

[0086] Comparative Example 6

[0087] A method for preparing a seal for an alkaline water electrolysis device:

[0088] The only difference between this comparative example and Example 1 is that PPVE is replaced by an equal weight of fluoroethylene ether (FEE), and finally a sealing member sample containing no PPVE but containing FEE is obtained.

[0089] Comparative Example 7

[0090] A method for preparing a seal for an alkaline water electrolysis device:

[0091] The only difference between this comparative example and Example 1 is that PPVE is replaced by an equal weight of ethyl fluoroacrylate, and finally a sealing member sample containing no PPVE but ethyl fluoroacrylate is obtained.

[0092] Test Method

[0093] Tensile Strength: Determined based on the test results of GB / T 1040.1-2018 plastics.

[0094] Sealing: The electrolytic cell is assembled using gaskets with a size of 50 mm × 50 mm. The test fluid is N2 and the tightening surface pressure is 10 MPa.

[0095] Anti-aging property: The obtained samples were immersed in 30% KOH solution at 300°C for aging, and their tensile strength was tested after 150 hours.

[0096] The above performance tests were performed on the seals obtained in each embodiment and comparative example, and the obtained test results are shown in Table 1.

[0097] Table 1

[0098] Tensile strength(MPa) <![CDATA[Sealing performance (Pa·m 3 / s)]]> Aging resistance (300℃, 30% KOH, 150h, MPa) Example 1 20.6 8.2E-05 20.2 Example 2 20.2 2.8E-05 16.3 Example 3 18.5 7.9E-05 15.7 Example 4 20.2 3.2E-05 19.8 Example 5 19.8 3.7E-05 19.6 Example 6 19.4 4.6E-05 19.0 Example 7 19.2 4.9E-05 19.0 Example 8 18.6 5.2E-05 18.2 Example 9 18.4 4.9E-05 18.1 Example 10 20.3 5.8E-05 19.7 Embodiment 11 20.1 6.7E-05 19.3 Example 12 20.2 6.4E-05 19.4 Comparative Example 1 13.2 4.5E-04 8.6 Comparative Example 2 18.5 9.2E-05 14.8 Comparative Example 3 17.2 3.2E-04 14.0 Comparative Example 4 17.4 1.3E-04 15.6 Comparative Example 5 18.2 1.0E-04 16.2 Comparative Example 6 17.9 1.6E-04 14.2 Comparative Example 7 16.5 3.5E-04 15.0

[0099] From the above description, it can be seen that the above embodiments of the present invention achieve the preparation of the seal of the alkaline water electrolysis device with high mechanical properties, high sealing performance and excellent anti-aging performance.

[0100] Specifically, from the comparison of the data in the examples, it can be seen that the temperature change in the preparation process affects the aging performance, the mixed preparation process affects its sealing performance, and the amount of monomer added affects the initial tensile strength. Without PPVE modification, the overall performance is relatively poor.

[0101] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those described herein, for example.

[0102] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a seal for an alkaline water electrolysis device, It is characterized in that include: Step S1, adding polytetrafluoroethylene into a solvent, and obtaining a first membrane liquid through a first stirring; Step S2, adding an initiator into the first membrane liquid, and obtaining a second membrane liquid through a second stirring; Step S3, adding perfluoropropyl vinyl ether into the second membrane liquid, and obtaining a third membrane liquid through a third stirring; Step S4, adding an inorganic filler into the third membrane liquid, and obtaining a fourth membrane liquid by a fourth stirring; Step S5, the fourth membrane liquid is sequentially subjected to a casting process and a sintering process to obtain the alkaline water electrolysis device seal.

2. The method for preparing the seal of the alkaline water electrolysis device according to claim 1, It is characterized in that Based on 100% weight of the polytetrafluoroethylene, the added amount of the perfluoropropyl vinyl ether is 5% to 6%.

3. A method for preparing a seal for an alkaline water electrolysis device according to claim 1 or 2, It is characterized in that The third stirring is performed at 55° C. to 60° C., and the stirring speed of the third stirring is 300 rpm to 350 rpm, and the time is 4 h to 5 h.

4. A method for preparing a seal for an alkaline water electrolysis device according to any one of claims 1 to 3, It is characterized in that The solvent is selected from one or more of petroleum ether, hexane, ethyl ether and n-butanol, preferably petroleum ether; Preferably, the solid content of the first membrane liquid is 20wt% to 25wt%.

5. A method for preparing a seal for an alkaline water electrolysis device according to any one of claims 1 to 4, It is characterized in that Based on the total weight of the first membrane liquid being 100%, the added amount of the initiator is 10% to 12%, and the initiator is barium sulfate and / or ammonium persulfate, preferably barium sulfate.

6. A method for preparing a seal for an alkaline water electrolysis device according to any one of claims 1 to 5, It is characterized in that The first stirring is performed at 60° C. to 65° C., and the stirring speed of the first stirring is 100 rpm to 300 rpm; The second stirring is performed at 80° C. to 90° C., and after the initiator is completely dispersed in the first membrane liquid, the stirring is continued for 5 min to 10 min.

7. A method for preparing a seal for an alkaline water electrolysis device according to any one of claims 1 to 6, It is characterized in that Based on the total weight of the third membrane liquid being 100%, the amount of the inorganic filler added is 60% to 70%, and the inorganic filler is selected from one or more of zirconium oxide, silicon oxide and aluminum oxide, preferably zirconium oxide; Preferably, after the fourth stirring, step S4 further comprises degassing the fourth membrane liquid at a speed of 25 rpm to 30 rpm.

8. A method for preparing a seal for an alkaline water electrolysis device according to any one of claims 1 to 7, It is characterized in that The casting speed of the casting process is 0.15 cm / min to 0.25 cm / min; The sintering temperature is 300°C to 400°C, and the sintering is carried out under the protection of an inert gas, preferably N 2 .

9. A seal for an alkaline water electrolysis device, It is characterized in that The alkaline water electrolysis device seal is prepared by the preparation method of the alkaline water electrolysis device seal according to any one of claims 1 to 8.

10. The alkaline water electrolysis device seal according to claim 9, It is characterized in that The tensile strength of the seal of the alkaline water electrolysis device is 18MPa-21MPa, and the sealing performance is 2.5E-05Pa·m 3 / s~8.5E-05Pa·m 3 / s.