Epoxy adhesive for bonding polyphenylene sulfide diaphragm and polytetrafluoroethylene gasket and preparation method of epoxy adhesive

Abstract

The invention discloses an epoxy adhesive for bonding a polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket and a preparation method of the epoxy adhesive, and belongs to the technical field of hydrogen production by alkaline electrolyzed water, the epoxy adhesive for the polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket comprises a component A and a component B, wherein the component A comprises epoxy resin, a monofunctional group type benzene ring rigid structure diluent, silane crosslinking modified nano zirconium oxide powder, polyphenylene sulfide micron-sized powder, nano silicon carbide powder and an auxiliary agent; and the component B is an amine curing agent. The adhesive prepared by the invention has the advantages of strong alkali resistance, high temperature resistance, high adaptability to base materials, low VOC (volatile organic compounds) and the like.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of hydrogen production by alkaline electrolysis of water, and particularly relates to an epoxy adhesive for bonding polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket and a preparation method thereof. BACKGROUND

[0002] In the field of hydrogen production by alkaline electrolysis of water, the running safety of the system and the high purity of the output gas are the core indicators that production enterprises are most concerned about. Because hydrogen and oxygen mixed together have an explosion risk, when the hydrogen content in oxygen reaches 4%, an explosion accident may occur. To ensure absolute safety, many enterprises even set the safety threshold more strictly, for example, when the hydrogen content in oxygen reaches 2%, forced shutdown protection is triggered. Therefore, how to effectively improve the separation purity of hydrogen and oxygen has become the key to ensuring the safe and stable operation of the system.

[0003] After years of practice and research, the industry has generally recognized that, in addition to selecting polyphenylene sulfide (PPS) diaphragms with excellent air tightness, improving the sealing performance of the entire electrolytic cell is crucial to ensuring gas purity. A typical alkaline electrolytic cell is composed of multiple electrolytic chambers stacked together, and the sealing function of each chamber mainly depends on the precise fit between the electrode plate, the polyphenylene sulfide diaphragm, and the polytetrafluoroethylene (PTFE) gasket. The traditional assembly method is to lay the PPS diaphragm on the diaphragm table of the electrode plate, then position and install the PTFE gasket according to the flow channel of the electrode plate, and finally place the electrode assembly. However, the existing technology faces a major systemic problem: there is currently a lack of in-depth research and unified standards on the compatibility between the depth of the diaphragm table of the electrode plate and the thickness of the diaphragm. When the sizes of the two do not match, even if a diaphragm material with high air tightness is used, after the electrolytic cell is assembled, the gas produced by electrolysis may bypass the diaphragm and pass through the interface gap between the electrode plate-diaphragm-gasket, resulting in abnormal transmission (as shown in FIG. d), which causes hydrogen and oxygen to penetrate each other, seriously reduces the purity of the gas, and threatens the safety of the system. Figure 2

[0004] To solve this key problem, the field urgently needs an innovative solution that can fundamentally eliminate the interface leakage path. For this purpose, the present application proposes to pre-bond the PTFE gasket and the PPS diaphragm into an integral assembly by using an adhesive. This integrated design can effectively prevent sealing failure caused by the mismatch between the depth of the diaphragm table and the thickness of the diaphragm, ensuring that the gas can only be normally transmitted through the diaphragm, thereby significantly improving the air tightness and gas purity of the system (as shown in FIG. d). Figure 2 ​However, there are huge material challenges to realize this concept. Alkaline electrolyzers usually use 30 wt% KOH solution as electrolyte and operate at high temperature up to 90℃ for a long time. Therefore, the adhesive used to bond PTFE gasket and PPS separator must have excellent resistance to strong alkali corrosion and excellent resistance to high temperature aging. In addition, PTFE material has extremely low surface energy and strong chemical inertness, so it is difficult for conventional adhesives to form effective bonding with it. Special treatment or design of specific bonding mechanism is required to achieve high strength bonding. Currently, there is no special adhesive on the market that can meet the above harsh working conditions at the same time.

[0005] Therefore, there is an urgent need to develop an environmentally friendly adhesive for PTFE / PPS composite components that has high alkali resistance, heat resistance, and high bonding strength. SUMMARY

[0006] To solve the above technical problems, the present application provides an epoxy adhesive for bonding polyphenylene sulfide separator-polytetrafluoroethylene gasket and a preparation method thereof. The adhesive prepared by the present application has the advantages of strong alkali resistance, high temperature resistance, high adaptability to substrates, and low VOC.

[0007] To achieve the above-mentioned purposes, the present application provides the following technical solutions:

[0008] An epoxy adhesive for bonding polyphenylene sulfide separator-polytetrafluoroethylene gasket, the raw materials including two components A and B;

[0009] The component A includes epoxy resin, monofunctional benzene ring rigid structure diluent, silane crosslinking modified nano zirconia powder, polyphenylene sulfide micron powder (1-500µm), nano silicon carbide powder, and additives.

[0010] The component B is an amine curing agent.

[0011] Optionally, the mass ratio of the component A to the component B is 100:33-55.

[0012] Optionally, the preparation process of the silane crosslinking modified nano zirconia powder is as follows:

[0013] The nano zirconia powder is uniformly dispersed in anhydrous ethanol using a high-speed stirrer, and the dispersion system is heated to 50℃-70℃ while stirring. After 0.5h, epoxy-functionalized silane coupling agent is added, and after 3h, amino-functionalized silane coupling agent is added. After 2h of crosslinking reaction, the silane crosslinking modified zirconia dispersion is obtained. Finally, centrifugation, water washing, drying, and crushing are performed to prepare the silane crosslinking modified nano zirconia powder.

[0014] Further, the mass ratio of the nanoscale zirconium oxide powder, the epoxy functional silane coupling agent and the amino functional silane coupling agent is 10:1:1-2.

[0015] Further, the epoxy functional silane coupling agent and the amino functional silane coupling agent are KH560 and KH792 respectively.

[0016] Optionally, the A component comprises the following raw materials in terms of mass percentage: epoxy resin 30%-45%, monofunctional benzene ring rigid structure diluent 2%-10%, silane crosslinking modified nanometer zirconium oxide powder 20%-31%, polyphenylene sulfide micron powder 5%-15%, nanometer silicon carbide powder 10%-20%, leveling agent 0.1%-5%, and defoaming agent 0.1%-5%.

[0017] Further, the epoxy resin is selected from at least one of E51 and MF-3010.

[0018] Further, the monofunctional benzene ring rigid structure diluent is phenyl glycidyl ether (690).

[0019] Further, the leveling agent is any one of BYK333 and Glide450.

[0020] Further, the defoaming agent is QS-A29.

[0021] Optionally, the B component is composed of the following raw materials in terms of mass percentage: QS-130A 50%-80%, polydiethyldiaminodiphenylmethane (purchased from Haining Luoyi Polymer Technology Co., Ltd., product model E200) 20%-50%.

[0022] The preparation method of the above-mentioned epoxy adhesive for polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket comprises the following steps:

[0023] The raw materials are weighed in terms of mass percentage, and then the A component and the B component are prepared respectively, and then stirred uniformly to prepare the epoxy adhesive for polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket.

[0024] A polyphenylene sulfide diaphragm-polytetrafluoroethylene integrated piece for hydrogen production by alkaline electrolysis of water, comprising polytetrafluoroethylene, a polyphenylene sulfide diaphragm and the above-mentioned epoxy adhesive.

[0025] A preparation method of a polyphenylene sulfide diaphragm-polytetrafluoroethylene integrated piece for hydrogen production by alkaline electrolysis of water, comprising the following steps:

[0026] The polytetrafluoroethylene sample is activated by using a sodium naphthalene treatment solution;

[0027] The activated polytetrafluoroethylene sample and the polyphenylene sulfide diaphragm are bonded by using the epoxy adhesive, and the polyphenylene sulfide diaphragm-polytetrafluoroethylene integrated piece for hydrogen production by alkaline electrolysis of water is prepared by maintaining at room temperature.

[0028] Compared with the prior art, the present application has the following advantages and technical effects:

[0029] (1) The adhesive prepared by the present application exhibits excellent heat resistance, which can meet the long-term stable operation demand under harsh working conditions of hydrogen production by alkaline electrolysis of water.

[0030] (2) Benefiting from the synergistic effect of polyphenylene sulfide micropowder and silane cross-linked modified nano zirconia, the adhesive prepared by the present application has excellent alkali corrosion resistance and can maintain stable structure and performance in a strong alkaline environment.

[0031] (3) The present application forms an integrated assembly by pre-bonding the diaphragm, adhesive and gasket, effectively eliminating the leakage path between the plate-diaphragm-gasket interface in traditional assembly, significantly improving the gas tightness of the electrolytic cell system, and thus ensuring the high purity output of hydrogen and oxygen.

[0032] (4) The design of the diaphragm-adhesive-gasket integrated assembly simplifies the on-site assembly process, avoids the complex operation of multi-component alignment installation, and greatly improves the overall assembly efficiency and consistency of the electrolytic cell.

[0033] (5) The silane cross-linked modified nano zirconia in the adhesive prepared by the present application can form a firm chemical bond with the surface-activated polytetrafluoroethylene gasket, thereby realizing high-strength and high-reliability bonding effect.

[0034] (6) The adhesive prepared by the present application is a solvent-free formula, does not contain volatile organic compounds (VOC), is green and environmentally friendly, and meets the requirements of modern industry for environmentally friendly materials. BRIEF DESCRIPTION OF DRAWINGS

[0035] The accompanying drawings, which form a part of the present application, are used to provide further understanding of the present application, and the schematic embodiments of the present application and their descriptions are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0036] Figure 1 It is a synthesis flow chart of the silane cross-linked modified zirconia powder of the present application;

[0037] Figure 2a is the electrode plate of the hydrogen electrolyzer for alkaline electrolysis water, b is the polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket assembly, c is the electrode plate-polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket assembly, d is the transmission mode of electrolysis generated gas when the polyphenylene sulfide diaphragm and the polytetrafluoroethylene gasket are not integrated, e is the polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket assembly, and the transmission mode of electrolysis generated gas;

[0038] Figure 3 It is the production flow chart of the gasket-diaphragm assembly in the effect example of the application.

[0039] Figure 4 a is the photo of the polytetrafluoroethylene strip-diaphragm assembly (using the adhesive of Example 1) before stretching after aging; b is the photo of the stretching failure form of the assembly (using the adhesive of Example 1); c is the photo of the gasket-diaphragm after running on the groove prepared by using the adhesive of Example 1, and d is the photo of the stretching failure form of the assembly prepared by using the adhesive of Comparative Example 1;

[0040] Figure 5 It is the schematic diagram of the action mechanism of the silane cross-linked modified nano zirconium oxide powder prepared by the application and polytetrafluoroethylene.

[0041] Figure 6 It is the purity monitoring of the gas generated by the ordinary assembled electrolyzer (i.e. the normal assembly of the diaphragm and the gasket);

[0042] Figure 7 It is the purity monitoring of the gas prepared by the diaphragm-gasket integrated alkaline tank of the application. DETAILED DESCRIPTION

[0043] The various illustrative embodiments of the application will now be described in detail in connection with the accompanying drawings. This description is not intended to be a limitation on the application, but rather a description of certain aspects, features, and embodiments of the application, and modifications can be made within the scope of the application.

[0044] It should be understood that the terms used herein are merely for the purpose of describing particular embodiments and are not intended to limit the application. In addition, for numerical ranges in the application, it should be understood that each intermediate value between the upper limit and the lower limit of the range is specifically disclosed. Each smaller range within the range of the stated value or the stated range and any other stated value or intermediate value within the stated range is also included in the application. The upper limit and the lower limit of these smaller ranges can be included or excluded independently.

[0045] Unless otherwise indicated, all technical and scientific terms have the same meaning as those one of ordinary skill in the art of the disclosure would understand. Although preferred methods and materials are described, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present disclosure. All documents mentioned herein are incorporated by reference to disclose and describe in further detail the methods and / or materials associated with the documents. In the case of conflict between the content of the specification and that of any document incorporated herein by reference, the content of the specification controls.

[0046] Many modifications and variations of the present disclosure described in the specification are possible without departing from the scope or spirit of the present disclosure. Other implementations of the present disclosure will be apparent to those skilled in the art from the specification. The specification and examples of the present disclosure are merely illustrative.

[0047] As used herein, "comprise", "comprising", "have", "having", "include", "including", "contain", "containing", and the like, are open-ended terms that are intended to mean including, but not limited to.

[0048] An epoxy adhesive for bonding a polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket, the composition of the material comprising component A and component B;

[0049] Component A comprises epoxy resin, monofunctional benzene ring rigid structure diluent, silane crosslinking modified nano zirconia powder, polyphenylene sulfide micron powder, nano silicon carbide powder, and additives;

[0050] The epoxy resin is any one of E51, MF-3010, or a mixture of the two;

[0051] The monofunctional benzene ring rigid structure diluent is phenyl glycidyl ether (690);

[0052] The silane crosslinking modified nano zirconia powder is self-made; as shown in the formula, the preparation process of the silane crosslinking modified nano zirconia powder is: Figure 1

[0053] (1) Use a high-speed stirrer to uniformly disperse the nano zirconia powder in anhydrous ethanol, pour the dispersion into a three-necked flask, and heat the dispersion system to 50-70°C while stirring. After 0.5 h, add the epoxy functional silane coupling agent, and after 3 h, add the amino functional silane coupling agent. After 2 h of crosslinking reaction, the silane crosslinking modified zirconia dispersion is obtained. The epoxy functional silane coupling agent and the amino functional silane coupling agent are KH560 and KH792, respectively;

[0054] (2) Centrifuge the dispersion obtained in step 1 to separate the liquid and solid, wash the solid repeatedly with purified water, dry, crush, and sieve to obtain the silane crosslinking modified zirconia powder;​

[0055] The assistant includes a leveling agent and a defoaming agent, wherein the leveling agent is any one of BYK333 or Glide450; the defoaming agent is QS-A29;

[0056] The B component consists of QS-130A 50%-80% and polydiethyldiaminodiphenylmethane 20%-50% by mass percentage.

[0057] The technical features of the present application are:

[0058] (1) In view of the extremely high heat resistance and alkali resistance requirements of the adhesive for alkaline electrolytic water hydrogen production electrolytic cell, the present application introduces polyphenylene sulfide micron powder and silane cross-linked modified nano zirconia filler into the adhesive system, which significantly improves the heat resistance and alkali corrosion resistance of the material. Among them, polyphenylene sulfide itself has excellent chemical stability, and silane cross-linked modified nano zirconia not only enhances the interfacial bonding force of the filler and the epoxy matrix, but also further improves the structural stability of the adhesive in high temperature and strong alkali environment.

[0059] (2) At present, there is still a lack of adaptive sealing design standard based on systematic research among the depth of the electrode plate diaphragm tank, the thickness of the commercially available diaphragm and the size of the gasket. This size mismatch easily leads to micro gaps at the interface of the electrode plate-diaphragm-gasket, causing abnormal cross penetration of hydrogen and oxygen in the cell, which seriously affects the gas purity. Therefore, the present application proposes to pre-bond the polytetrafluoroethylene gasket and the polyphenylene sulfide diaphragm into an integrated assembly through a special adhesive. This integrated structure can effectively eliminate the interface leakage path during subsequent assembly process, greatly improving the gas tightness of the electrolytic cell, thereby ensuring the stable output of high-purity gas.

[0060] (3) The design of diaphragm-adhesive-gasket integrated assembly simplifies the on-site assembly process of the electrolytic cell, avoids the complex operation of traditional multiple component one-by-one alignment installation, and significantly improves the assembly efficiency and batch consistency of the electrolytic cell.

[0061] (4) The conventional epoxy adhesive has high hardness after curing, which may cause stress concentration and even damage to the soft gasket or diaphragm. The present application adds polyphenylene sulfide micron powder with good compatibility with the matrix material, which moderately adjusts the modulus and hardness of the cured adhesive layer, and reduces the risk of mechanical damage to the sealing material. At the same time, combined with the use of alkali-resistant and corrosion-resistant nano silicon carbide and modified zirconia fillers, the overall weather resistance and long-term service stability of the adhesive are further enhanced.

[0062] (5) PTFE is difficult to be effectively bonded by conventional adhesives due to its extremely low surface energy. However, after specific surface treatment (such as sodium naphthalene treatment), the C-F bonds on its surface can be broken and active oxygen-containing functional groups such as hydroxyl groups can be introduced. The silane crosslinking modified nano-zirconia filler used in the present application contains siloxane groups, which can chemically react with the hydroxyl groups on the activated PTFE surface to form stable covalent bonds, thereby significantly improving the bonding strength and durability between the adhesive and the PTFE gasket. The principle is shown in Figure 5 PTFE surface contains a large number of C-F bonds, which exhibit extremely strong chemical inertness. After sodium naphthalene treatment, hydroxyl groups and other groups appear on the surface. The unreacted siloxane groups of the silane crosslinking modified zirconia in the adhesive can condense with the activated gasket surface hydroxyl groups to form extremely stable Si-O bonds. This design realizes high-strength and reliable bonding of inert materials under harsh working conditions.

[0063] In the present application, "room temperature" refers to 20-30℃ unless otherwise specified.

[0064] The raw materials used in the present application are commercially available.

[0065] The technical solutions of the present application are further illustrated by the following examples.

[0066] Example 1

[0067] A preparation method of an epoxy adhesive for bonding a polyphenylene sulfide separator and a PTFE gasket, comprising the following steps:

[0068] 1. Preparation of silane crosslinking modified zirconia: use a high-speed stirrer to uniformly disperse 10 g of nano-sized zirconia powder in 100 ml of anhydrous ethanol, pour the dispersion into a 250 mL three-necked flask, and heat the dispersion system to 65℃ while stirring. After 0.5 h, add 1 g of KH560, and after 3 h, add 1 g of KH792. After 2 h of crosslinking reaction, silane crosslinking modified zirconia dispersion is obtained.

[0069] Centrifuge the obtained dispersion to separate the liquid and solid, wash the solid repeatedly with purified water, dry, crush and sieve to obtain silane crosslinking modified zirconia powder;

[0070] 2. Preparation of component A: mix 80 g of E51 resin, 10 g of phenyl glycidyl ether (690), 60 g of silane crosslinking modified nano-zirconia powder, 15 g of polyphenylene sulfide micron-sized powder, 30 g of nano-silicon carbide, 2 g of leveling agent BYK333, and 3 g of defoaming agent QS-A29 to obtain component A.

[0071] 3. Preparation of B component: Take 60 g of QS-130A and 20 g of polydiethyldiaminodiphenylmethane, and stir them uniformly for use;

[0072] 4. Mix the A component and the B component uniformly according to a mass ratio of A:B of 100:36 to obtain an epoxy adhesive.

[0073] Example 2

[0074] A preparation method of an epoxy adhesive for bonding a polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket, comprising the following steps:

[0075] 1. Preparation of silane cross-linked modified zirconia: use a high-speed stirrer to uniformly disperse 10 g of nano-sized zirconia powder in 120 ml of anhydrous ethanol, pour the dispersion into a 250 mL three-necked flask, and heat the dispersion system to 70°C while stirring, then add 1 g of KH560 after 0.5 h, add 2 g of KH792 after 3 h, and obtain a silane cross-linked modified zirconia dispersion after cross-linking for another 2 h;

[0076] Centrifuge the obtained dispersion to separate the liquid and the solid, repeatedly wash the solid with purified water, dry and crush it to pass through a sieve to obtain silane cross-linked modified zirconia powder;

[0077] 2. Preparation of A component: mix 50 g of E51 and 50 g of MF-3010 resin, 8 g of phenyl glycidyl ether (690), 70 g of silane cross-linked modified nano-sized zirconia powder, 20 g of polyphenylene sulfide micron-sized powder, 30 g of nano-sized silicon carbide, 1 g of leveling agent BYK333, and 2 g of defoaming agent QS-A29 uniformly to obtain the A component;

[0078] 3. Preparation of B component: take 30 g of QS-130A and 30 g of polydiethyldiaminodiphenylmethane, and stir them uniformly for use;

[0079] 4. Mix the A component and the B component uniformly according to a mass ratio of A:B of 100:33 to obtain an epoxy adhesive.

[0080] Example 3

[0081] A preparation method of an epoxy adhesive for bonding a polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket, comprising the following steps:

[0082] 1. Preparation of silane cross-linked modified zirconia: use a high-speed stirrer to uniformly disperse 15 g of nano-sized zirconia powder in 120 ml of anhydrous ethanol, pour the dispersion into a 250 mL three-necked flask, and heat the dispersion system to 55°C while stirring, then add 1 g of KH560 after 0.5 h, add 1 g of KH792 after 3 h, and obtain a silane cross-linked modified zirconia dispersion after cross-linking for another 2 h;

[0083] The obtained dispersion was centrifuged to separate the liquid and solid. The solid was repeatedly washed with pure water, dried, pulverized and sieved to obtain silane crosslinked modified zirconium oxide powder.

[0084] 2. Preparation of component A: Take 100g of MF-3010 resin, 5g of phenyl glycidyl ether (690), 60g of silane crosslinked modified nano zirconia powder, 30g of polyphenylene sulfide micron-sized powder, 30g of nano silicon carbide, 1g of leveling agent BYK333, and 2g of defoamer QS-A292g and mix them evenly to obtain component A.

[0085] 3. Preparation of component B: Take 80g of QS-130A and 20g of poly(diethyldiaminodiphenylmethane), stir them evenly and set aside for later use;

[0086] 4. Mix component A and component B evenly at a mass ratio of A:B of 100:55 to obtain epoxy adhesive.

[0087] Comparative Example 1

[0088] The difference from Example 1 is that the silane crosslinked modified zirconium oxide was replaced with zirconium oxide powder (i.e., unmodified). Other preparation conditions were the same as in Example 1.

[0089] Example 1 (Aging polyphenylene sulfide diaphragm - polytetrafluoroethylene sample)

[0090] 1. Surface treatment of polytetrafluoroethylene (PTFE) samples: Several 100mm*25mm*3mm PTFE samples were activated using sodium naphthalene treatment solution;

[0091] 2. Cut a polyphenylene sulfide membrane to 100mm*25mm*2mm;

[0092] 3. The activated polytetrafluoroethylene strip and the polyphenylene sulfide membrane were bonded together using the adhesive from Example 1 to form a single piece (see preparation process). Figure 3 );

[0093] 4. Cure the integrated component at room temperature for 24 hours;

[0094] 5. Five samples were aged in 30% KOH at 120℃ for 128 hours, while another five samples served as a blank control (unaged).

[0095] 6. The adhesion of the strip was tested using a tensile testing machine, and the results are shown in Table 1.

[0096] Table 1 Tensile mechanical properties of polytetrafluoroethylene-polyphenylene sulfide diaphragm strips

[0097] Sample Name Failure Force / N Failure Mode Unaged-1 517 Gasket Material Cohesive Failure Unaged-2 538 Gasket Material Cohesive Failure Unaged-3 525 Gasket Material Cohesive Failure Unaged-4 557 Gasket Material Cohesive Failure Unaged-5 494 Gasket Material Cohesive Failure Mean 526.2 / Aged Sample-6 431 Bondline Aged Sample-7 513 Gasket Material Cohesive Failure Aged Sample-8 535 Gasket Material Cohesive Failure Aged Sample-9 521 Gasket Material Cohesive Failure Aged Sample-10 530 Gasket Material Cohesive Failure Mean 506

[0098] Note: The bonding area of the integrated sample of the diaphragm-polytetrafluoroethylene is 25 mm*10 mm.

[0099] Conclusion: As shown in Table 1, the bonding strength of the unaged and aged samples does not decrease significantly after tensile failure, and the failure mode of the integrated sample is cohesive failure in the gasket, which proves that the adhesive of the application is suitable for the sealing system of the alkaline electrolytic cell.

[0100] The pre-and post-tension photos of the aged sample 8 are shown in Figure 4 (a), the tensile failure mode photo of sample 8 is shown in Figure 4 (b), the post-operation photo of the gasket-diaphragm is shown in Figure 4 (c), and the post-operation photo of the gasket-diaphragm is shown in Figure 4 As shown in c, the bonding area of the integrated sample of the gasket-diaphragm is not damaged due to the extrusion of the electrode plate after the operation.

[0101] In addition, the activated polytetrafluoroethylene sample and the polyphenylene sulfide diaphragm are bonded using the adhesive of Comparative Example 1 to form an integrated sample, and the specific tensile mechanical test results are shown in Table 2.

[0102] Table 2 Tensile mechanical test of polytetrafluoroethylene-polyphenylene sulfide diaphragm sample

[0103] Sample Name Failure Force / N Failure Mode Unaged-1 327 Bondline Unaged-2 278 Bondline Unaged-3 364 Bondline

[0104] Note: The bonding area of the integrated sample of the diaphragm-polytetrafluoroethylene is 25 mm*10 mm.

[0105] As shown in Table 2, the zirconium oxide is not modified by silane crosslinking and added to the adhesive, and the tensile failure strength of the unaged sample is about 39% lower than the data in Table 1, and the failure mode of the sample is adhesive face failure (as shown in d). Compared with Table 1, it shows that the modified zirconium oxide can improve the bonding strength of the adhesive and the substrate. Figure 4

[0106] Effect Example 2 (polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket integrated sample for electrolytic cell operation)

[0107] 1. Prepare 11 groups of integrated diaphragm-gasket assemblies (integrated assemblies prepared by the adhesive of Example 1) for alkaline cell operation experiments;

[0108] 2. The electrolytic cell platform is SDQZ-1 / 1.6 of Shandong Hydrogen Boat Green Energy Technology Development Co., Ltd.

[0109] 3. The operation conditions and gas purity data are shown in Figure 7 .

[0110] Figure 6 The purity of the gas generated by the normally assembled electrolytic cell (i.e., the diaphragm and gasket are normally assembled) is monitored; ​

[0111] Figure 7 Purity monitoring of gas produced for the alkali tank of the diaphragm-gasket integrated piece of the present application;

[0112] From Figure 6-7 It can be seen from the comparison of hydrogen purity and oxygen purity that the integrated assembly of the polyphenylene sulfide diaphragm and gasket has a more obvious improvement on the gas purity. This shows that the gasket-diaphragm integration is beneficial to improve the gas purity and ensure the production safety.

[0113] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any change or replacement easily thought of by those skilled in the art within the technical range disclosed by the present application should be covered within the protection scope of the present application.

Claims

1. An epoxy adhesive for polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket, characterized in that, The raw materials consist of two components, A and B. Component A includes epoxy resin, monofunctional benzene ring rigid structure diluent, silane crosslinked modified nano-zirconia powder, polyphenylene sulfide micron-sized powder, nano-silicon carbide powder, and additives. Component B is an amine curing agent; The mass ratio of component A to component B is 100:33-55.

2. The epoxy adhesive for polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket according to claim 1, characterized in that, The preparation process of the silane crosslinked modified nano-zirconia powder is as follows: Nanoscale zirconia powder was dispersed in anhydrous ethanol and heated to 50℃-70℃ while stirring. After 0.5h, an epoxy-functionalized silane coupling agent was added, followed by an amino-functionalized silane coupling agent after 3h. After the crosslinking reaction was carried out for 2h, the mixture was centrifuged, washed with water, dried and pulverized in sequence to prepare the silane crosslinked modified nanoscale zirconia powder.

3. The epoxy adhesive for a polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket according to claim 2, characterized in that, The mass ratio of the nano-sized zirconium oxide powder, epoxy-functionalized silane coupling agent, and amino-functionalized silane coupling agent is 10:1:1-2.

4. The epoxy adhesive for a polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket according to claim 2, characterized in that, The epoxy-functionalized silane coupling agent and the amino-functionalized silane coupling agent are KH560 and KH792, respectively.

5. The epoxy adhesive for a polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket according to claim 1, characterized in that, Component A, by mass percentage, comprises the following raw materials: Epoxy resin 30%-45%, monofunctional benzene ring rigid structure diluent 2%-10%, silane crosslinked modified nano zirconia powder 20%-31%, polyphenylene sulfide micron-sized powder 5%-15%, nano silicon carbide powder 10%-20%, leveling agent 0.1%-5%, defoamer 0.1%-5%.

6. The epoxy adhesive for polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket according to claim 5, characterized in that, The epoxy resin is selected from at least one of E51 and MF-3010; and / or, The monofunctional benzene ring rigid structure diluent is phenyl glycidyl ether; and / or... The leveling agent is either BYK333 or Glide450; and / or The defoamer is QS-A29.

7. The epoxy adhesive for polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket according to claim 1, characterized in that, Component B, by mass percentage, consists of the following raw materials: 50%-80% QS-130A and 20%-50% poly(diethyldiaminodiphenylmethane).

8. A method for preparing an epoxy adhesive for a polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket as described in any one of claims 1-7, characterized in that, Includes the following steps: Weigh the raw materials according to the mass percentage, prepare component A and component B respectively, and then stir the two components evenly to prepare the epoxy adhesive for polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket.

9. A polyphenylene sulfide diaphragm-polytetrafluoroethylene integrated component for alkaline water electrolysis to produce hydrogen, characterized in that, The raw materials include polytetrafluoroethylene, polyphenylene sulfide diaphragm, and the epoxy adhesive for polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket as described in any one of claims 1-7.

10. A method for preparing a polyphenylene sulfide membrane-polytetrafluoroethylene integrated component for alkaline water electrolysis to produce hydrogen as described in claim 9, characterized in that, Includes the following steps: Polytetrafluoroethylene was activated using a sodium naphthalene treatment solution; The activated polytetrafluoroethylene and polyphenylene sulfide diaphragm are bonded together with epoxy adhesive using the polyphenylene sulfide diaphragm-polytetrafluoroethylene gasket as described in any one of claims 1-7, and cured at room temperature to prepare the polyphenylene sulfide diaphragm-polytetrafluoroethylene integral part.

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