A perfluoroether rubber-metal composite seal and a method of making the same

Abstract

This invention relates to a perfluoroether rubber-metal composite seal and its preparation method, belonging to the field of composite sealing material technology. The perfluoroether rubber-metal composite seal includes a metal skeleton, a perfluoroether rubber sealing layer, and an adhesive layer. The metal skeleton has an adhesive bonding surface, and the adhesive layer is disposed on the adhesive bonding surface. The perfluoroether rubber sealing layer is bonded to the metal skeleton through the adhesive layer. The adhesive layer comprises a two-component adhesive. The adhesive bonding surface of the metal skeleton is a rough surface. The perfluoroether rubber sealing layer is obtained by vulcanization molding of a cyano-cured perfluoroether rubber compound. This invention addresses the problems of existing perfluoroether rubber-metal seals, such as easy sealing failure at high temperatures, poor bonding effect, and poor reliability.

Description

Technical Field

[0001] This invention relates to the field of composite sealing materials technology, specifically to a perfluoroether rubber-metal composite seal and its preparation method. Background Technology

[0002] In the field of high-end equipment manufacturing, especially in semiconductor thermal process equipment, the seals of critical components such as valves, pumps, and reaction chambers need to be continuously exposed to a high-temperature environment of 250℃~300℃, and may come into contact with corrosive or strong oxidizing process gases such as WF6 (tungsten hexafluoride), HCl (hydrogen chloride), and O2 (oxygen). This places almost stringent requirements on the long-term heat resistance, chemical corrosion resistance, and the ability to maintain elasticity and sealing capacity (i.e., low compression set) of the sealing materials.

[0003] Perfluoroelastomer (PFE) is one of the known synthetic elastomers with the highest heat resistance and most comprehensive chemical resistance, capable of long-term operation at temperatures exceeding 300°C. However, when combining PFE with a metal skeleton to manufacture structural components such as valve plates, gates, and O-ring gaskets, two major technological bottlenecks are encountered: First, the peroxide vulcanization system commonly used for PFE exhibits insufficient cross-linking network stability under sustained ultra-high temperatures, easily leading to a sharp increase in compression set and rapid attenuation of sealing force, resulting in failure. Second, PFE has extremely low surface energy and strong chemical inertness, making it difficult to form a strong and durable bond with the metal substrate. Ordinary adhesives and surface treatment processes are prone to interface failure after long-term high-temperature aging, causing the rubber layer to peel off from the metal skeleton, leading to media leakage and major equipment failure. Furthermore, while there have been attempts to use general-purpose fluororubber adhesives in existing technologies, their bonding strength and durability cannot meet the reliability requirements for long-term operation above 250°C.

[0004] Therefore, it is necessary to propose new measures to overcome the above-mentioned shortcomings. Summary of the Invention

[0005] The purpose of this invention is to provide a perfluoroether rubber-metal composite seal and its preparation method, so as to solve the problems of easy failure of sealing ability, poor adhesion and reliability of existing perfluoroether rubber-metal seals at high temperatures.

[0006] To achieve the above objectives, in a first aspect, the present invention provides a perfluoroether rubber-metal composite seal, comprising a metal skeleton, a perfluoroether rubber sealing layer, and an adhesive layer; the metal skeleton has an adhesive bonding surface, the adhesive layer is disposed on the adhesive bonding surface, and the perfluoroether rubber sealing layer is bonded to the metal skeleton through the adhesive layer; wherein, the adhesive layer comprises a two-component adhesive; the adhesive bonding surface of the metal skeleton is a rough surface; the perfluoroether rubber sealing layer is obtained by vulcanization molding of a cyano-cured perfluoroether rubber compound.

[0007] In one possible implementation, the cyano-cured perfluoroether rubber compound comprises, by weight, 100 parts of raw perfluoroether rubber; 15-25 parts of filler; and 1.0-2.5 parts of crosslinking agent.

[0008] In one possible implementation, the perfluoroether rubber raw rubber comprises tetrafluoroethylene, perfluoroalkyl vinyl ether, and a vulcanizing point monomer; the vulcanizing point monomer has a cyano group.

[0009] In one possible implementation, the dry film thickness of the adhesive layer is 7 μm to 10 μm.

[0010] In one possible implementation, the surface roughness Ra of the bonding surface of the metal skeleton is 2μm~4.5μm.

[0011] In one possible implementation, the metal frame is a metal valve plate frame in a semiconductor heat treatment device.

[0012] In a second aspect, the present invention also provides a method for preparing a perfluoroether rubber-metal composite seal as described in the first aspect or any possible implementation thereof, the method comprising:

[0013] The bonding surfaces of the metal skeleton are roughened to form a rough surface;

[0014] A two-component adhesive is applied to the roughened bonding surfaces to form an adhesive layer;

[0015] A cyano-cured perfluoroether rubber compound is combined with a metal skeleton through an adhesive layer and then subjected to vulcanization molding to form a perfluoroether rubber sealing layer, resulting in a perfluoroether rubber-metal composite seal.

[0016] In one possible implementation, a cyano-cured perfluoroether rubber compound is combined with a metal skeleton via an adhesive layer and then subjected to vulcanization molding to form a perfluoroether rubber sealing layer, resulting in a perfluoroether rubber-metal composite seal comprising:

[0017] The cyano-cured perfluoroether rubber compound is combined with a metal skeleton through an adhesive layer and then subjected to compression molding and vulcanization to obtain an intermediate product.

[0018] The intermediate product is subjected to a secondary vulcanization treatment to form a perfluoroether rubber sealing layer, resulting in a perfluoroether rubber-metal composite seal.

[0019] In one possible implementation, the compression molding vulcanization process is carried out at a temperature of 160°C to 170°C and a pressure of 5 MPa to 12 MPa.

[0020] In one possible implementation, the secondary vulcanization process includes:

[0021] The vulcanization was carried out at a constant temperature for 1.5 hours, and then the temperature was increased to 70℃~90℃ at a rate of 1.5℃ / min~2℃ / min.

[0022] The temperature was kept constant at 70℃~90℃ for 1.5h, and then the temperature was increased to 120℃~140℃ at a rate of 1.5℃ / min~2℃ / min.

[0023] The temperature was kept constant at 120℃~140℃ for 1.5h, and then the temperature was increased to 170℃~190℃ at a rate of 1.5℃ / min~2℃ / min.

[0024] The temperature was kept constant at 170℃~190℃ for 1.5h, and then the temperature was increased to 220℃~240℃ at a rate of 1.5℃ / min~2℃ / min.

[0025] Vulcanization was carried out at a constant temperature of 220℃~240℃ for 16 hours.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] This invention provides a perfluoroether rubber-metal composite seal, comprising a metal skeleton, a perfluoroether rubber sealing layer, and an adhesive layer. Further, the metal skeleton has an adhesive bonding surface, and the adhesive layer is disposed on the adhesive bonding surface, allowing the perfluoroether rubber sealing layer to be bonded to the adhesive bonding surface of the metal skeleton through the adhesive layer, forming a strong, durable, and reliable adhesive bond. The adhesive bonding surface of the metal skeleton is a rough surface, the adhesive layer comprises a two-component adhesive, and the perfluoroether rubber sealing layer is obtained by vulcanizing a cyano-cured perfluoroether rubber compound. This invention provides a perfluoroether rubber-metal composite seal, which, through the synergistic effect of a specific rubber formulation, an optimized adhesive system, and the special surface morphology of the metal skeleton, enables the seal to possess excellent high-temperature compression set performance and adhesive interface durability in high-temperature environments up to 300°C. This solves the problems of easy sealing failure, poor adhesion and reliability of existing perfluoroether rubber-metal seals at high temperatures. It can be used stably for a long time in extreme high-temperature, strong oxidizing and corrosive media environments, and can meet the stringent requirements of ultra-high temperature long-term sealing in fields such as semiconductor manufacturing. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained from these drawings without creative effort.

[0029] Figure 1 The image shown is a schematic diagram of a metal skeleton provided in an embodiment of this application;

[0030] Figure 2 The diagram shown is a structural schematic of a perfluoroether rubber-metal composite seal provided in an embodiment of this application.

[0031] Figure 3 The diagram shown is another structural schematic of the metal skeleton provided in this application embodiment;

[0032] Figure 4 The diagram shown is another structural schematic of the perfluoroether rubber-metal composite seal provided in the embodiments of this application;

[0033] Figure 5 The diagram shows a flowchart of the preparation method of the perfluoroether rubber-metal composite seal provided in the embodiments of this application.

[0034] The diagram is labeled as follows:

[0035] 1-Metal skeleton; 10-Adhesive bonding surface; 2-Perfluoroether rubber sealing layer. Detailed Implementation

[0036] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0037] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0038] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integral connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] Furthermore, in the description of this invention, the terms "first," "second," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance. Of course, such terms can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in a sequence other than those illustrated or described herein.

[0040] It should also be noted that although the order of steps is mentioned in the method description, in some cases, steps may be performed in a different order than that described here, and this should not be interpreted as a restriction on the order of steps.

[0041] This application proposes a perfluoroether rubber-metal composite seal and its preparation method to solve the problems of easy sealing failure, poor adhesion, and low reliability of existing perfluoroether rubber-metal seals at high temperatures. It can combine excellent elastic sealing performance and high adhesion reliability at the rubber-metal interface under extreme high-temperature conditions, making it suitable for long-term reliable sealing in extreme environments such as semiconductor thermal processing equipment and aerospace.

[0042] The following detailed description is provided in conjunction with the accompanying drawings and specific embodiments.

[0043] Figure 1 The image shown is a schematic diagram of a metal skeleton provided in an embodiment of this application; Figure 2 The image shown is a schematic diagram of a perfluoroether rubber-metal composite seal provided in an embodiment of this application. Figure 3 The diagram shown is another structural schematic of the metal skeleton provided in this application embodiment; Figure 4 The diagram shown is another structural schematic of the perfluoroether rubber-metal composite seal provided in the embodiment of this application.

[0044] like Figures 1-4 As shown in the figure, an embodiment of this application provides a perfluoroether rubber-metal composite seal, including a metal skeleton 1, a perfluoroether rubber sealing layer 2, and an adhesive layer (not shown in the figure). Further, the metal skeleton 1 has an adhesive bonding surface 10, and the adhesive layer is disposed on the adhesive bonding surface 10, allowing the perfluoroether rubber sealing layer 2 to be bonded to the adhesive bonding surface 10 of the metal skeleton 1 through the adhesive layer, forming a strong, durable, and reliable adhesive bond. The adhesive bonding surface 10 of the metal skeleton 1 is a rough surface. The rough adhesive bonding surface 10 has micro-rough structures such as pits and pores, which can increase the actual surface area of ​​the adhesive bonding surface 10 of the metal skeleton 1, significantly enhancing the bonding strength between the metal skeleton 1 and the adhesive layer and the perfluoroether rubber sealing layer 2, extending the service life of the perfluoroether rubber-metal composite seal (hereinafter referred to as the seal) in long-term high-temperature or oxidative corrosion environments, and improving the high-temperature durability and reliability of the seal.

[0045] The adhesive layer includes a two-component adhesive. Using a two-component adhesive as the bonding layer between the perfluoroelastomer rubber sealing layer 2 and the metal skeleton 1 can form a high-strength, high-temperature aging-resistant interfacial bond between the two. This helps overcome the bonding difficulties caused by the surface inertness of the perfluoroelastomer rubber and maintains good adhesion after prolonged high-temperature aging, further improving the high-temperature durability and reliability of the seal during long-term service.

[0046] The perfluoroether rubber sealing layer 2 is made by vulcanizing a cyano-cured perfluoroether rubber compound. Compared to perfluoroether rubber based on a peroxide vulcanization system, cyano-cured perfluoroether rubber has a higher operating temperature and excellent resistance to media at high temperatures, which is beneficial for further improving the weather resistance and long-term service capability of the seals in high-temperature and oxidative corrosion environments. Simultaneously, the aromatic heterocyclic cross-linked network structure formed by cyano curing is stable and has good resistance to compression set, which is beneficial for further improving the high-temperature durability and sealing performance of the seals. Furthermore, the cyano-cured perfluoroether rubber and the two-component adhesive can achieve a stable interfacial bond, further ensuring the durability of the seals under high-temperature conditions.

[0047] Therefore, the perfluoroether rubber-metal composite seal provided in this application embodiment, through the synergistic effect of a specific rubber formulation, an optimized adhesive system, and the special surface morphology of the metal skeleton 1, enables the seal to possess excellent high-temperature compression set performance and adhesive interface durability in high-temperature environments below 300°C. This solves the problems of easy sealing failure, poor adhesion effect, and poor reliability of existing perfluoroether rubber-metal seals at high temperatures. It can be used stably for a long time in extreme high-temperature, strong oxidizing, and corrosive media environments, and can meet the stringent requirements for ultra-high temperature and long-term sealing in fields such as semiconductor manufacturing (such as diffusion, oxidation, chemical vapor deposition, and other thermal processes), aerospace engine systems, and petrochemicals.

[0048] As one possible implementation, the cyano-cured perfluoroether rubber compound comprises, by weight, the following components: 100 parts of raw perfluoroether rubber; 15-25 parts of filler; and 1.0-2.5 parts of crosslinking agent.

[0049] Perfluoroether rubber raw rubber (hereinafter referred to as raw rubber) is the matrix material of cyano-cured perfluoroether rubber compound (hereinafter referred to as compound). Fillers can enhance the mechanical strength of the compound, adjust its hardness and processing fluidity. By controlling the filler to 15-25 parts and dispersing it evenly in the rubber matrix, sufficient mechanical strength of the seal is ensured, while avoiding the decrease in rubber fluidity and deterioration of compression set caused by excessive filler. This further improves the elastic sealing effect and reliability of the seal at high temperatures. Crosslinking agents can react with the cyano groups in the raw rubber to form a high-temperature resistant crosslinking network. By controlling the crosslinking agent to 1.0-2.5 parts, the crosslinking agent can fully react with the cyano-cured perfluoroether rubber raw rubber to form a stable aromatic heterocyclic crosslinking network. If the crosslinking agent content is too low, the crosslinking network is incomplete, and the strength and elasticity of the seal are poor; if the crosslinking agent content is too high, the crosslinking density is too high, the rubber becomes hard and brittle, and the fluidity is also poor, which also affects the elasticity of the seal.

[0050] Based on this, the synergistic effect of the crosslinking agent and filler ratio results in a moderate crosslinking density and good strength in the compound. Compared to peroxide vulcanization systems, the cyano vulcanization system in this embodiment exhibits significantly reduced compression set in high-temperature environments below 300°C, which is beneficial for further improving the bonding effect of the seals and the long-term sealing reliability under extreme conditions.

[0051] For example, the filler included in the cyano-cured perfluoroether rubber compound may be 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25 parts by weight, etc. This is just an example and is not a specific limitation.

[0052] For example, the crosslinking agent included in the cyano-cured perfluoroether rubber compound may be 1.0 parts, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, 2.0 parts, 2.1 parts, 2.2 parts, 2.3 parts, 2.4 parts, or 2.5 parts by weight, etc. This is only an example and is not a specific limitation.

[0053] For example, the crosslinking agent may be selected from at least one or more combinations of tetraphenyltin, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (BOAP), amine compounds, bis(aminothiophenol) compounds and dicyandiphenylmethane, etc., which are merely examples and are not specifically limited.

[0054] For example, the filler may be selected from at least one or more combinations of carbon black, barium sulfate, nano zinc oxide, silica, alumina and PTFE (polytetrafluoroethylene) micro powder, etc., which are only examples and are not specifically limited.

[0055] For example, the crosslinking agent can be 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (BOAP), and the filler can be N990 carbon black. This is just an example and is not a specific limitation.

[0056] In some examples, the raw perfluoroether rubber comprises tetrafluoroethylene, perfluoroalkyl vinyl ether, and a vulcanizing point monomer; the vulcanizing point monomer has a cyano group.

[0057] Based on this, under the action of the crosslinking agent, the cyano functional groups carried by the vulcanization point monomer can undergo crosslinking reactions to form an aromatic heterocyclic crosslinking network. The thermal stability of this crosslinking network is significantly better than that of the peroxide vulcanization system, making the perfluoroether rubber sealing layer 2 (hereinafter referred to as the sealing layer) less prone to breakage during long-term service under high-temperature conditions of 250℃~300℃. This effectively inhibits stress relaxation and permanent deformation accumulation in the sealing layer under high-temperature compression. Furthermore, the aromatic heterocyclic crosslinking network formed after cyano vulcanization also exhibits excellent chemical stability, allowing the sealing layer to maintain the integrity of the crosslinking network even when exposed to strong oxidizing and corrosive process gases. Therefore, introducing a vulcanization point monomer with cyano groups helps ensure the sealing effect of the seal and further improves the weather resistance and long-term service capability of the seal under high-temperature and oxidative corrosion environments.

[0058] For example, the sulfidation point monomer with a cyano group can be a cyano-containing fluoroolefin or a cyano-containing fluorovinyl ether, etc. This is only an example and is not a specific limitation.

[0059] For example, the sulfide point monomer with a cyano group can be selected from one or more combinations of perfluoro (4-cyanobutyl vinyl ether), perfluoro-8-cyano-5-methyl-3,6-dioxa-1-octene, perfluoro (2-phenylfluoropropyl vinyl ether), or other cyano-containing fluoroolefins or fluorovinyl ethers, etc. This is only an example and is not a specific limitation.

[0060] In some examples, the compression set of the cyano-cured perfluoroether rubber compound after hot air aging at 300°C for 72 hours is less than 30%. This demonstrates that even after aging at extreme high temperatures of 300°C for 72 hours, the compression set of the cyano-cured perfluoroether rubber compound in this application embodiment can still be controlled below 30%, indicating that the compound has excellent anti-aging capabilities and resilience retention. This allows the seals provided in this application embodiment to maintain excellent sealing reliability for a long time under high-temperature conditions of 250°C to 300°C, avoiding seal failure due to excessive compression set and extending the service life of the seals.

[0061] As one possible implementation, a two-component adhesive (hereinafter referred to as the adhesive) includes component A and component B. Component A is the main agent, providing the main adhesive structure, while component B is a curing agent that initiates crosslinking or polymerization reactions in the main agent. Further, based on a total weight of 100 parts by weight for components A and B, component A can be 80-90 parts by weight, and component B can be 10-20 parts by weight. That is, the weight ratio of component A to component B can be 4:1 to 9:1. Within this weight range, components A and B can be fully mixed and undergo a moderate crosslinking reaction, which is beneficial for forming an adhesive layer with high cohesive strength and excellent thermal stability. This allows the adhesive layer to maintain high peel strength and interfacial integrity under long-term high-temperature conditions, ensuring high adhesive strength and excellent high-temperature durability, while also guaranteeing good process adaptability. If the proportion of component A is too large, the curing agent of component B will be insufficient, the adhesive will not cure completely, the interfacial bonding force will be poor, and the bonding strength at high temperature will be difficult to guarantee. If the proportion of component A is too small, the amount of component B will be excessive, which will easily lead to over-crosslinking, making the adhesive layer brittle and accelerating failure after high-temperature aging.

[0062] In some examples, the weight ratio of component A to component B can be 4:1, 5:1, 6:1, 7:1, 8:1, or 9:1, etc. These are just examples and are not specific limitations.

[0063] For example, with a total weight of 100 parts by weight for components A and B, component A can be 85 parts by weight and component B can be 15 parts by weight, that is, the weight ratio of components A to B can be 85:15. This is just an example and is not a specific limitation.

[0064] Furthermore, after components A and B are mixed evenly, they are diluted with an organic solvent and then applied.

[0065] Furthermore, after components A and B are mixed evenly, a mixed adhesive is formed. The weight ratio of the mixed adhesive to the organic solvent can be 1:3 to 1:5. By limiting the ratio of the mixed adhesive to the organic solvent, the mixed adhesive can fully penetrate the bonding surface of the metal skeleton to form a uniform coating; and promote co-crosslinking with the perfluoroether rubber, which is beneficial to further ensure high bonding strength and interface integrity under long-term high-temperature conditions.

[0066] For example, the weight ratio of the mixed adhesive formed by uniformly mixing component A and component B to the organic solvent can be 1:3, 1:3.5, 1:4, 1:4.5 or 1:5, etc. This is just an example and is not a specific limitation.

[0067] For example, the weight ratio of the mixed adhesive formed by mixing component A and component B evenly to the organic solvent can be 1:4. This is just an example and is not a specific limitation.

[0068] In some examples, the organic solvent may be one or more combinations of ketones, esters, and aromatic hydrocarbons, etc. This is only an example and is not a specific limitation.

[0069] For example, butanone can be chosen as an organic solvent; this is only an example and not a specific limitation.

[0070] In some examples, the dry film thickness of the adhesive layer can be 7μm to 10μm. By controlling the dry film thickness of the adhesive layer to 7μm to 10μm, a relatively thin adhesive layer can be formed on the bonding surface of the metal skeleton. Furthermore, a thinner adhesive layer helps ensure that the seal fails on the rubber body rather than the adhesive interface or adhesive layer under stress, while significantly reducing interfacial stress concentration and thermal expansion mismatch stress, improving fatigue life, resistance to media penetration, and dimensional stability, and also helping to reduce adhesive usage and achieve rapid curing processes. If the dry film thickness of the adhesive layer is too thin, localized adhesive shortages may occur, resulting in decreased adhesive adhesion and affecting the bonding effect and weather resistance of the seal. If the dry film thickness of the adhesive layer is too thick, the adhesive layer itself may become a weak point under stress, accelerating fatigue failure and affecting assembly accuracy.

[0071] For example, the dry film thickness of the adhesive layer can be 7μm, 7.5μm, 8μm, 8.5μm, 9μm, 9.5μm or 10μm, etc. This is just an example and is not a specific limitation.

[0072] As one possible implementation, the surface roughness Ra of the bonding surface of the metal skeleton can be 2μm to 4.5μm. Within this surface roughness range, a uniform microstructure can be formed on the metal surface, and the adhesive can fully fill these microstructures, resulting in good bonding strength after the adhesive layer cures. Furthermore, appropriate surface roughness helps to uniformly transfer thermal stress and dynamic loads, reducing the risk of interfacial delamination and further extending the service life of the seal under high temperature or oxidative corrosion conditions. If the surface roughness Ra of the bonding surface of the metal skeleton is too small, i.e., the bonding surface is too smooth, it is difficult to ensure sufficient wetting of the adhesive on the bonding surface of the metal skeleton, and the interfacial adhesion is also poor. If the surface roughness Ra of the bonding surface of the metal skeleton is too large, the adhesive may not be able to completely fill the microstructure of the bonding surface, and gaps may appear in the adhesive layer at the bonding surface, which also affects the bonding effect.

[0073] For example, the surface roughness Ra of the bonding surface of the metal skeleton can be 2μm, 2.5μm, 3μm, 3.5μm, 4μm or 4.5μm, etc. This is just an example and is not a specific limitation.

[0074] In some examples, the bonding surfaces of the metal skeleton can be roughened to create a rough surface.

[0075] In some examples, the roughening process can be at least one or more combinations of mechanical roughening and / or chemical roughening.

[0076] For example, the roughening process can be a combination of at least one or more mechanical roughening processes, such as sandblasting, laser roughening, etc.

[0077] For example, roughening treatment can be sandblasting roughening treatment; this is just an example and is not a specific limitation.

[0078] Furthermore, differentiated surface treatment processes can be adopted for different metal skeletons. Here, "different metal skeletons" refers to different materials, shapes, structures, equipment used, and / or processing requirements, etc. This is just an example and is not a specific limitation.

[0079] In some examples, such as Figures 1-4 As shown, the metal skeleton 1 can be a metal valve plate skeleton in semiconductor heat treatment equipment. The valve plate is a key actuator in semiconductor heat treatment equipment (such as oxidation furnaces, diffusion furnaces, CVD / PVD reaction chambers, etc.), which achieves the opening, closing, regulation, or sealing of gas paths through reciprocating movement or rotation; it is also called a gate or valve. The seals at the valve plate need to be continuously exposed to a high-temperature environment of 250℃~300℃ and may come into contact with strong oxidizing or corrosive process gases such as WF6, HCl, or O2. This requires the sealing layer at the metal valve plate skeleton to have long-term heat resistance, chemical corrosion resistance, and the ability to maintain elasticity and sealing at high temperatures. Therefore, using the metal valve plate skeleton as the metal skeleton 1 in this embodiment can improve the valve plate's resistance to high-temperature cycling and dynamic fatigue under long-term high-temperature and oxidative corrosion conditions. This helps ensure that the bonding interface of the valve plate does not fail under frequent opening and closing impacts, thereby significantly extending the reliable service life of the valve plate in semiconductor heat treatment equipment and meeting the stringent requirements of the semiconductor field for high-temperature long-term sealing.

[0080] For example, the metal valve plate frame can be Figures 1-2 The stainless steel knife gate frame shown can also be... Figures 3-4 The aluminum alloy valve plate frame shown is only an example and is not a specific limitation.

[0081] For example, the metal skeleton 1 can also be a metal skeleton in heat treatment equipment in other fields, such as aerospace engine systems and petrochemical fields, which also have strict requirements for high-temperature and long-term sealing.

[0082] It should be noted that the metal valve plate skeleton in the embodiments of this application is not limited to only Figures 1-4 The shape and structure shown can be modified according to the specific interface or channel specifications of the heat treatment equipment.

[0083] For example, the material of the metal frame may include one or more of stainless steel, carbon steel, aluminum alloy, titanium alloy, etc. This is only an example and is not a specific limitation.

[0084] For example, the material of the metal frame may include stainless steel or aluminum alloy; this is just an example and is not a specific limitation.

[0085] Figure 5 The diagram shows a flowchart of the preparation method of the perfluoroether rubber-metal composite seal provided in the embodiments of this application.

[0086] Based on the same inventive concept, such as Figure 5 As shown in the embodiments of this application, a method for preparing a perfluoroether rubber-metal composite seal is also provided. The method for preparing the perfluoroether rubber-metal composite seal includes:

[0087] S100 roughens the bonding surface of the metal skeleton to form a rough surface.

[0088] S200 involves applying a two-component adhesive to the roughened bonding surfaces to form an adhesive layer.

[0089] S300 involves combining a cyano-cured perfluoroether rubber compound with a metal skeleton through an adhesive layer and then performing vulcanization molding to form a perfluoroether rubber sealing layer, resulting in a perfluoroether rubber-metal composite seal.

[0090] Compared with the prior art, the beneficial effects of the preparation method of the perfluoroether rubber-metal composite seal are the same as those of the perfluoroether rubber-metal composite seal described in the above embodiments, and will not be repeated here.

[0091] As one possible implementation, before applying the two-component adhesive to the roughened bonding surface in step S200 to form the adhesive layer, and after roughening the bonding surface of the metal skeleton in step S100, the method for preparing the perfluoroether rubber-metal composite seal further includes: preparing the two-component adhesive.

[0092] In some examples, the preparation method of the two-component adhesive includes: mixing component A and component B at a weight ratio of 4:1 to 9:1 to obtain a mixed adhesive; then adding an organic solvent with a weight of 3 to 5 times the total weight of the mixed adhesive to dilute it, and stirring evenly to obtain the two-component adhesive.

[0093] As one possible implementation, in step S300, the cyano-cured perfluoroether rubber compound is combined with a metal skeleton through an adhesive layer and then subjected to vulcanization molding to form a perfluoroether rubber sealing layer, resulting in a perfluoroether rubber-metal composite seal comprising:

[0094] Step S301: The cyano-cured perfluoroether rubber compound is combined with a metal skeleton through an adhesive layer and subjected to compression molding and vulcanization to obtain an intermediate product.

[0095] Step S302: The intermediate product is subjected to a secondary vulcanization treatment to form a perfluoroether rubber sealing layer, thereby obtaining a perfluoroether rubber-metal composite seal.

[0096] Based on this, when vulcanizing cyano-cured perfluoroether rubber compound and metal skeleton, the cyano-cured perfluoroether rubber compound can be combined with the adhesive-coated metal skeleton and placed in a mold for compression molding. This allows the rubber vulcanization process and the adhesive curing process to proceed simultaneously, ensuring that the rubber crosslinking network and the adhesive crosslinking network form and interpenetrate simultaneously, resulting in a strong interfacial bonding layer. This significantly improves the peel resistance of the adhesive layer under ultra-high temperature long-term service conditions. The intermediate product after compression molding is then subjected to a secondary vulcanization treatment to obtain a perfluoroether rubber-metal composite seal. The secondary vulcanization treatment further increases the crosslinking density, making the crosslinking network more regular and stable. This significantly reduces the compression set of the seal under high temperature long-term service conditions, slows down the attenuation of sealing contact pressure, and enhances high-temperature durability, thus meeting the long-term reliable sealing requirements under ultra-high temperature conditions of 250℃~300℃.

[0097] In some examples, the compression molding vulcanization temperature is 160℃~170℃, and the pressure is 5MPa~12MPa. Based on this, these compression molding vulcanization conditions are beneficial for further ensuring the formation of a stable aromatic heterocyclic crosslinking network in the cyano-cured perfluoroether rubber, while simultaneously achieving integrated co-crosslinking molding of the cyano-cured perfluoroether rubber and the metal skeleton through adhesives. This avoids under-curing or over-curing, reduces compression set, and further ensures the interfacial bonding strength and long-term high-temperature service reliability of the seals.

[0098] For example, the temperature of compression molding vulcanization can be 160℃, 161℃, 162℃, 163℃, 164℃, 165℃, 166℃, 167℃, 168℃, 169℃ or 170℃, etc. This is just an example and is not a specific limitation.

[0099] For example, the pressure of compression molding vulcanization can be 5 MPa, 5.5 MPa, 6 MPa, 6.5 MPa, 7 MPa, 7.5 MPa, 8 MPa, 8.5 MPa, 9 MPa, 9.5 MPa, 10 MPa, 10.5 MPa, 11 MPa, 11.5 MPa or 12 MPa, etc., which are only examples and are not specifically limited.

[0100] In some examples, the secondary vulcanization process includes: maintaining a constant temperature vulcanization at room temperature for 1.5 hours, followed by increasing the temperature to 70°C to 90°C at a rate of 1.5°C / min to 2°C / min; maintaining a constant temperature vulcanization at 70°C to 90°C for 1.5 hours, followed by increasing the temperature to 120°C to 140°C at a rate of 1.5°C / min to 2°C / min; maintaining a constant temperature vulcanization at 120°C to 140°C for 1.5 hours, followed by increasing the temperature to 170°C to 190°C at a rate of 1.5°C / min to 2°C / min; maintaining a constant temperature vulcanization at 170°C to 190°C for 1.5 hours, followed by increasing the temperature to 220°C to 240°C at a rate of 1.5°C / min to 2°C / min; and maintaining a constant temperature vulcanization at 220°C to 240°C for 16 hours.

[0101] Based on this, the secondary vulcanization process employs a stepped heating procedure, increasing the temperature sequentially from room temperature to 70℃~90℃, 120℃~140℃, and 170℃~190℃, with each temperature stage being held constant for 1.5 hours. The final temperature is increased to 220℃~240℃, and vulcanization is carried out at 220℃~240℃ for 16 hours. This five-stage stepped secondary vulcanization process enables progressive post-crosslinking based on the crosslinked network formed during compression molding, releasing molding internal stress step by step. This facilitates the complete elimination of low-molecular-weight byproducts during vulcanization, further densifying the crosslinked network, and making the aromatic heterocyclic network structure more regular, significantly reducing compression set. Simultaneously, it ensures a denser interfacial bond between the adhesive layer and the perfluoroether rubber sealing layer. Furthermore, the secondary vulcanization process can achieve multiple synergies with specific rubber formulations, optimized adhesive systems, and metal skeleton surface treatment processes, enabling the seals to achieve excellent high-temperature compression set performance and adhesive interface durability, meeting the long-term reliable sealing requirements of the semiconductor field, aerospace engine systems, and petrochemical fields under high-temperature and strong oxidative corrosion conditions.

[0102] For example, the room temperature for secondary vulcanization treatment refers to room temperature of 20℃~30℃. The specific temperature value can be adjusted according to the actual operation needs, and this application embodiment does not limit it.

[0103] For example, the heating rate at each stage may be the same or different, and this application embodiment does not limit this.

[0104] For example, the secondary vulcanization process may include: maintaining a constant temperature vulcanization at room temperature for 1.5 hours, then increasing the temperature to 80°C at a rate of 1.5°C / min; maintaining a constant temperature vulcanization at 80°C for 1.5 hours, then increasing the temperature to 130°C at a rate of 1.5°C / min; maintaining a constant temperature vulcanization at 130°C for 1.5 hours, then increasing the temperature to 180°C at a rate of 1.5°C / min; maintaining a constant temperature vulcanization at 180°C for 1.5 hours, then increasing the temperature to 230°C at a rate of 1.5°C / min; and maintaining a constant temperature vulcanization at 230°C for 16 hours. This is merely an example and is not a specific limitation.

[0105] The present application will now be described with reference to specific embodiments. The embodiments described are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0106] In this application, all units indicating the content of raw materials are based on weight in parts, expressed in grams, unless otherwise stated. Furthermore, the methods used to determine the technical specifications of this application are standard methods used in the art, and specific details can be found in the relevant national standards, unless otherwise stated. Additionally, other raw materials used in this application refer to raw materials commonly used in the art.

[0107] Example 1:

[0108] The perfluoroether rubber-metal composite seal provided in this application includes a metal skeleton, a perfluoroether rubber sealing layer, and an adhesive layer. The metal skeleton has an adhesive bonding surface, and the adhesive layer is disposed on the adhesive bonding surface. The perfluoroether rubber sealing layer is bonded to the metal skeleton through the adhesive layer. The adhesive layer includes a two-component adhesive. The adhesive bonding surface of the metal skeleton is a rough surface. The perfluoroether rubber sealing layer is obtained by vulcanizing a cyano-cured perfluoroether rubber compound. By weight, the cyano-cured perfluoroether rubber compound contains the following components: 100 parts of raw perfluoroether rubber; 15-25 parts of filler; and 1.0-2.5 parts of crosslinking agent. In this embodiment, the metal skeleton is a machined 304 stainless steel gate skeleton; the two-component high-temperature resistant adhesive is ThinkBond® 233A / 200B, purchased from Shanghai Lerui Curing Technology Co., Ltd.; the perfluoroether rubber raw material is PFR-2050-R, purchased from Fujian Yonghong High-Tech Materials Co., Ltd.; the filler is thermally pyrolyzed carbon black N990, purchased from Cabot Corporation of the United States; and the crosslinking agent is 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (BOAP), purchased from Zigong Tianlong Chemical Co., Ltd.

[0109] The preparation method of the perfluoroether rubber-metal composite seal provided in this application includes the following steps:

[0110] Step 1, Pre-treatment of stainless steel frame:

[0111] A machined 304 stainless steel gate frame was subjected to sandblasting on its upper surface sealing and bonding area using 80-mesh white corundum sand at a pressure of 0.5 MPa. The surface roughness Ra after treatment was approximately 3.3 μm. The frame was then cleaned with ethyl acetate solution for 5 minutes to remove grease and dust, and then dried in an oven at 80°C for 20 minutes for later use.

[0112] The second step is to prepare and apply the adhesive:

[0113] A two-component high-temperature resistant adhesive was selected. Component A and component B were mixed evenly at a weight ratio of 85:15, and then diluted with methyl ethyl ketone (MEK) at a weight ratio of 1:4. The mixed adhesive was then evenly applied to the sandblasted surface of the guillotine frame using a brush, ensuring uniform coating. The mixture was allowed to air dry at room temperature for 30 minutes to form a dry film layer with a thickness of approximately 8 μm.

[0114] The third step is compression molding and vulcanization:

[0115] The compound formulation includes: 100 parts cyano-perfluoroether raw rubber, 1.2 parts crosslinking agent, and 25 parts carbon black. Sufficient amounts of the cyano-cured perfluoroether rubber compound are weighed and cut into strips to obtain a pre-formed compound. The pre-formed compound and the adhesive-coated gate skeleton are placed together into a mold cavity preheated to 165°C. A pressure of 6 MPa is applied on a flat vulcanizing machine, and compression curing is performed for 30 minutes. During this process, the rubber undergoes vulcanization and crosslinking, while the adhesive is fully cured by heat, achieving a strong bond between the rubber and the metal.

[0116] Step 4, secondary vulcanization treatment:

[0117] The molded composite seals are demolded and then placed in an aging chamber for a staged secondary vulcanization treatment to stabilize product performance and eliminate internal stress. Specifically, the vulcanization is carried out at room temperature for 1.5 hours, followed by a heating rate of 1.5℃ / min to 80℃; then at 80℃ for 1.5 hours, the temperature is increased to 130℃ at a rate of 1.5℃ / min; then at 130℃ for 1.5 hours, the temperature is increased to 180℃ at a rate of 1.5℃ / min; then at 180℃ for 1.5 hours, the temperature is increased to 230℃ at a rate of 1.5℃ / min; finally, the vulcanization is carried out at 230℃ for 16 hours.

[0118] Example 2:

[0119] The perfluoroether rubber-metal composite seal provided in this application includes a metal skeleton, a perfluoroether rubber sealing layer, and an adhesive layer. The metal skeleton has an adhesive bonding surface, and the adhesive layer is disposed on the adhesive bonding surface. The perfluoroether rubber sealing layer is bonded to the metal skeleton through the adhesive layer. The adhesive layer includes a two-component adhesive. The adhesive bonding surface of the metal skeleton is a rough surface. The perfluoroether rubber sealing layer is obtained by vulcanizing a cyano-cured perfluoroether rubber compound. By weight, the cyano-cured perfluoroether rubber compound contains the following components: 100 parts of raw perfluoroether rubber; 15-25 parts of filler; and 1.0-2.5 parts of crosslinking agent. In this embodiment, the metal skeleton is a machined aluminum alloy valve plate skeleton; the two-component high-temperature resistant adhesive is ThinkBond® 233A / 200B, purchased from Shanghai Lerui Curing Technology Co., Ltd.; the perfluoroether rubber raw material is PFR-2050-R, purchased from Fujian Yonghong High-Tech Materials Co., Ltd.; the filler is thermally pyrolyzed carbon black N990, purchased from Cabot Corporation of the United States; and the crosslinking agent is 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (BOAP), purchased from Zigong Tianlong Chemical Co., Ltd.

[0120] The preparation method of the perfluoroether rubber-metal composite seal provided in this application includes the following steps:

[0121] Step 1, Pre-treatment of aluminum alloy frame:

[0122] A machined aluminum alloy valve plate skeleton was subjected to sandblasting of its upper surface sealing groove area using 120-mesh white corundum sand at a pressure of 0.5 MPa. The surface roughness Ra after treatment was approximately 3.8 μm. The skeleton was then cleaned with ethyl acetate solution for 5 minutes to remove grease and dust, and then dried in an oven at 80°C for 20 minutes for later use.

[0123] The second step is to prepare and apply the adhesive:

[0124] A two-component high-temperature resistant adhesive was selected. Component A and component B were mixed evenly at a weight ratio of 85:15, and then diluted with methyl ethyl ketone (MEK) at a weight ratio of 1:4. The mixed adhesive was evenly applied to the sandblasted valve plate skeleton surface using a brush, ensuring uniform coating. The mixture was then allowed to air dry at room temperature for 30 minutes to form a dry film layer with a thickness of approximately 9 μm.

[0125] The third step is compression molding and vulcanization:

[0126] The compound formulation includes: 100 parts cyano-perfluoroether raw rubber, 1.2 parts crosslinking agent, and 25 parts carbon black. Sufficient amounts of the cyano-cured perfluoroether rubber compound are weighed and cut into strips to obtain a pre-formed compound. The pre-formed compound and the valve plate skeleton coated with adhesive are placed together into a mold cavity preheated to 165°C. A pressure of 10 MPa is applied on a flat vulcanizing machine, and compression molding is performed for 30 minutes. During this process, the rubber undergoes vulcanization and crosslinking, while the adhesive is completely cured by heat, achieving a strong bond between the rubber and the metal.

[0127] Step 4, secondary vulcanization treatment:

[0128] The molded composite seals are demolded and then placed in an aging chamber for a staged secondary vulcanization treatment to stabilize product performance and eliminate internal stress. Specifically, the vulcanization is carried out at room temperature for 1.5 hours, followed by a heating rate of 1.5℃ / min to 80℃; then at 80℃ for 1.5 hours, the temperature is increased to 130℃ at a rate of 1.5℃ / min; then at 130℃ for 1.5 hours, the temperature is increased to 180℃ at a rate of 1.5℃ / min; then at 180℃ for 1.5 hours, the temperature is increased to 230℃ at a rate of 1.5℃ / min; finally, the vulcanization is carried out at 230℃ for 16 hours.

[0129] Example 3:

[0130] The perfluoroether rubber-metal composite seal provided in this application includes a metal skeleton, a perfluoroether rubber sealing layer, and an adhesive layer. The metal skeleton has an adhesive bonding surface, and the adhesive layer is disposed on the adhesive bonding surface. The perfluoroether rubber sealing layer is bonded to the metal skeleton through the adhesive layer. The adhesive layer includes a two-component adhesive. The adhesive bonding surface of the metal skeleton is a rough surface. The perfluoroether rubber sealing layer is obtained by vulcanizing a cyano-cured perfluoroether rubber compound. By weight, the cyano-cured perfluoroether rubber compound contains the following components: 100 parts of raw perfluoroether rubber; 15-25 parts of filler; and 1.0-2.5 parts of crosslinking agent. In this embodiment, the metal skeleton is a machined 304 stainless steel gate skeleton; the two-component high-temperature resistant adhesive is ThinkBond® 233A / 200B, purchased from Shanghai Lerui Curing Technology Co., Ltd.; the perfluoroether rubber raw material is PFR-2050-R, purchased from Fujian Yonghong High-Tech Materials Co., Ltd.; the filler is thermally pyrolyzed carbon black N990, purchased from Cabot Corporation of the United States; and the crosslinking agent is 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (BOAP), purchased from Zigong Tianlong Chemical Co., Ltd.

[0131] The preparation method of the perfluoroether rubber-metal composite seal provided in this application includes the following steps:

[0132] Step 1, Pre-treatment of stainless steel frame:

[0133] A machined 304 stainless steel gate frame was subjected to sandblasting on its upper surface sealing and bonding area using 80-mesh white corundum sand at a pressure of 0.5 MPa. The surface roughness Ra after treatment was approximately 2 μm. The frame was then cleaned with ethyl acetate solution for 5 minutes to remove grease and dust, and then dried in an oven at 80°C for 20 minutes for later use.

[0134] The second step is to prepare and apply the adhesive:

[0135] A two-component high-temperature resistant adhesive was selected. Component A and component B were mixed evenly at a weight ratio of 80:20, and then diluted with methyl ethyl ketone (MEK) at a weight ratio of 1:3. The mixed adhesive was then evenly applied to the sandblasted surface of the guillotine frame using a brush, ensuring uniform coating. The mixture was allowed to air dry at room temperature for 30 minutes to form a dry film layer with a thickness of approximately 7 μm.

[0136] The third step is compression molding and vulcanization:

[0137] The compound formulation includes: 100 parts cyano-perfluoroether raw rubber, 2.5 parts crosslinking agent, and 15 parts carbon black. Sufficient amounts of the cyano-cured perfluoroether rubber compound are weighed and cut into strips to obtain a pre-formed compound. The pre-formed compound and the adhesive-coated gate skeleton are placed together into a mold cavity preheated to 160°C. A pressure of 12 MPa is applied on a flat vulcanizing machine, and compression molding is performed for 30 minutes. During this process, the rubber undergoes vulcanization and crosslinking, while the adhesive is completely cured by heat, achieving a strong bond between the rubber and the metal.

[0138] Step 4, secondary vulcanization treatment:

[0139] The molded composite seals are demolded and then placed in an aging chamber for a staged secondary vulcanization treatment to stabilize product performance and eliminate internal stress. Specifically, the vulcanization is carried out at room temperature for 1.5 hours, followed by a heating rate of 2°C / min to 70°C; at 70°C, the vulcanization is carried out at a constant temperature for 1.5 hours, followed by a heating rate of 2°C / min to 120°C; at 120°C, the vulcanization is carried out at a constant temperature for 1.5 hours, followed by a heating rate of 2°C / min to 170°C; at 170°C, the vulcanization is carried out at a constant temperature for 1.5 hours, followed by a heating rate of 2°C / min to 220°C; and finally, the vulcanization is carried out at 220°C for 16 hours.

[0140] Example 4:

[0141] The perfluoroether rubber-metal composite seal provided in this application includes a metal skeleton, a perfluoroether rubber sealing layer, and an adhesive layer. The metal skeleton has an adhesive bonding surface, and the adhesive layer is disposed on the adhesive bonding surface. The perfluoroether rubber sealing layer is bonded to the metal skeleton through the adhesive layer. The adhesive layer includes a two-component adhesive. The adhesive bonding surface of the metal skeleton is a rough surface. The perfluoroether rubber sealing layer is obtained by vulcanizing a cyano-cured perfluoroether rubber compound. By weight, the cyano-cured perfluoroether rubber compound contains the following components: 100 parts of raw perfluoroether rubber; 15-25 parts of filler; and 1.0-2.5 parts of crosslinking agent. In this embodiment, the metal skeleton is a machined 304 stainless steel gate skeleton; the two-component high-temperature resistant adhesive is ThinkBond® 233A / 200B, purchased from Shanghai Lerui Curing Technology Co., Ltd.; the perfluoroether rubber raw material is PFR-2050-R, purchased from Fujian Yonghong High-Tech Materials Co., Ltd.; the filler is thermally pyrolyzed carbon black N990, purchased from Cabot Corporation of the United States; and the crosslinking agent is 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (BOAP), purchased from Zigong Tianlong Chemical Co., Ltd.

[0142] The preparation method of the perfluoroether rubber-metal composite seal provided in this application includes the following steps:

[0143] Step 1, Pre-treatment of stainless steel frame:

[0144] A machined 304 stainless steel gate frame was subjected to sandblasting on its upper surface sealing and bonding area using 80-mesh white corundum sand at a pressure of 0.5 MPa. The surface roughness Ra after treatment was approximately 4.5 μm. The frame was then cleaned with ethyl acetate solution for 5 minutes to remove grease and dust, and then dried in an oven at 80°C for 20 minutes for later use.

[0145] The second step is to prepare and apply the adhesive:

[0146] A two-component high-temperature resistant adhesive was selected. Component A and component B were mixed evenly at a weight ratio of 90:10, and then diluted with methyl ethyl ketone (MEK) at a weight ratio of 1:5. The mixed adhesive was then evenly applied to the sandblasted surface of the guillotine frame using a brush, ensuring uniform coating. The mixture was allowed to air dry at room temperature for 30 minutes to form a dry film layer with a thickness of approximately 10 μm.

[0147] The third step is compression molding and vulcanization.

[0148] The compound formulation includes: 100 parts cyano-perfluoroether raw rubber, 1.0 part crosslinking agent, and 20 parts carbon black. Sufficient cyano-cured perfluoroether rubber compound is weighed and cut into strips to obtain a pre-formed compound. The pre-formed compound and the adhesive-coated gate skeleton are placed together into a mold cavity preheated to 170°C. A pressure of 5 MPa is applied on a flat vulcanizing machine, and compression curing is performed for 30 minutes. During this process, the rubber undergoes vulcanization and crosslinking, while the adhesive is completely cured by heat, achieving a strong bond between the rubber and the metal.

[0149] Step 4, secondary vulcanization treatment:

[0150] The molded composite seals are demolded and then placed in an aging chamber for a staged secondary vulcanization treatment to stabilize product performance and eliminate internal stress. Specifically, the vulcanization is carried out at room temperature for 1.5 hours, followed by a heating rate of 1.5℃ / min to 90℃; at 90℃, the vulcanization is carried out at a constant temperature for 1.5 hours, followed by a heating rate of 1.7℃ / min to 140℃; at 140℃, the vulcanization is carried out at a constant temperature for 1.5 hours, followed by a heating rate of 1.8℃ / min to 190℃; at 190℃, the vulcanization is carried out at a constant temperature for 1.5 hours, followed by a heating rate of 1.75℃ / min to 240℃; finally, the vulcanization is carried out at 240℃ for 16 hours.

[0151] Example 5:

[0152] The perfluoroether rubber-metal composite seal provided in this application includes a metal skeleton, a perfluoroether rubber sealing layer, and an adhesive layer. The metal skeleton has an adhesive bonding surface, and the adhesive layer is disposed on the adhesive bonding surface. The perfluoroether rubber sealing layer is bonded to the metal skeleton through the adhesive layer. The adhesive layer includes a two-component adhesive. The adhesive bonding surface of the metal skeleton is a rough surface. The perfluoroether rubber sealing layer is obtained by vulcanizing a cyano-cured perfluoroether rubber compound. By weight, the cyano-cured perfluoroether rubber compound contains the following components: 100 parts of raw perfluoroether rubber; 15-25 parts of filler; and 1.0-2.5 parts of crosslinking agent. In this embodiment, the metal skeleton is a machined 304 stainless steel gate skeleton; the two-component high-temperature resistant adhesive is ThinkBond® 233A / 200B, purchased from Shanghai Lerui Curing Technology Co., Ltd.; the perfluoroether rubber raw material is PFR-2050-R, purchased from Fujian Yonghong High-Tech Materials Co., Ltd.; the filler is thermally pyrolyzed carbon black N990, purchased from Cabot Corporation of the United States; and the crosslinking agent is 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (BOAP), purchased from Zigong Tianlong Chemical Co., Ltd.

[0153] The preparation method of the perfluoroether rubber-metal composite seal provided in this application includes the following steps:

[0154] Step 1, Pre-treatment of stainless steel frame:

[0155] A machined 304 stainless steel gate frame was subjected to sandblasting on its upper surface sealing and bonding area using 80-mesh white corundum sand at a pressure of 0.5 MPa. The surface roughness Ra after treatment was approximately 3.3 μm. The frame was then cleaned with ethyl acetate solution for 5 minutes to remove grease and dust, and then dried in an oven at 80°C for 20 minutes for later use.

[0156] The second step is to prepare and apply the adhesive:

[0157] A two-component high-temperature resistant adhesive was selected. Component A and component B were mixed evenly at a weight ratio of 75:25, and then diluted with methyl ethyl ketone (MEK) at a weight ratio of 1:4. The mixed adhesive was then evenly applied to the sandblasted surface of the guillotine frame using a brush, ensuring uniform coating. The mixture was allowed to air dry at room temperature for 30 minutes to form a dry film thickness of approximately 8 μm.

[0158] The third step is compression molding and vulcanization.

[0159] The compound formulation includes: 100 parts cyano-perfluoroether raw rubber, 1.8 parts crosslinking agent, and 21 parts carbon black. Sufficient amounts of the cyano-cured perfluoroether rubber compound are weighed and cut into strips to obtain a pre-formed compound. The pre-formed compound and the adhesive-coated gate skeleton are placed together into a mold cavity preheated to 165°C. A pressure of 8 MPa is applied on a flat vulcanizing machine, and compression molding is performed for 30 minutes. During this process, the rubber undergoes vulcanization and crosslinking, while the adhesive is fully cured by heat, achieving a strong bond between the rubber and the metal.

[0160] Step 4, secondary vulcanization treatment:

[0161] The molded composite seals are demolded and then placed in an aging chamber for a staged secondary vulcanization treatment to stabilize product performance and eliminate internal stress. Specifically, the vulcanization is carried out at room temperature for 1.5 hours, followed by a heating rate of 1.7℃ / min to 80℃; at 80℃, the vulcanization is carried out at a constant temperature for 1.5 hours, followed by a heating rate of 1.8℃ / min to 130℃; at 130℃, the vulcanization is carried out at a constant temperature for 1.5 hours, followed by a heating rate of 1.7℃ / min to 180℃; at 180℃, the vulcanization is carried out at a constant temperature for 1.5 hours, followed by a heating rate of 2℃ / min to 230℃; finally, the vulcanization is carried out at 230℃ for 16 hours.

[0162] Comparative Example 1:

[0163] This comparative example provides a perfluoroether rubber-stainless steel composite seal. Unlike Examples 1 to 5, the perfluoroether rubber sealing layer in this comparative example is obtained by vulcanizing a peroxide-cured perfluoroether rubber compound. By weight, the peroxide-cured perfluoroether rubber compound in Comparative Example 1 comprises: 100 parts peroxide-cured raw perfluoroether rubber, 1.5 parts crosslinking agent, and 25 parts carbon black. The peroxide-cured perfluoroether rubber raw material is PFR-95HT, purchased from Stratco; the carbon black is thermally pyrolyzed carbon black N990, purchased from Cabot Corporation (USA); and the crosslinking agent is powdered bis-25 vulcanizing agent, purchased from Kemawei New Materials Co., Ltd. All other aspects are the same as in Example 1.

[0164] The preparation method of the perfluoroether rubber-metal composite seal provided in this comparative example is the same as that in Example 1.

[0165] Comparative Example 2:

[0166] This comparative example provides a perfluoroether rubber-stainless steel composite seal. Unlike Examples 1 to 5 above, the adhesive layer in this comparative example is a one-component silane coupling agent adhesive, specifically ThinkBond 3H, purchased from Shanghai Lerui Curing Technology Co., Ltd. Everything else is the same as in Example 1.

[0167] The preparation method of the perfluoroether rubber-metal composite seal provided in this comparative example is the same as that in Example 1.

[0168] Comparative Example 3:

[0169] This comparative example provides a perfluoroether rubber-stainless steel composite seal. Unlike Examples 1 to 5 above, the adhesive layer in this comparative example is a general-purpose fluororubber single-component adhesive, specifically model BDL637008, purchased from Bolin Chemical. All other aspects are the same as in Example 1.

[0170] The preparation method of the perfluoroether rubber-metal composite seal provided in this comparative example is the same as that in Example 1.

[0171] To verify the high-temperature compression set performance and adhesive interface durability of the perfluoroether rubber-metal composite seal, under the same conditions, the seals prepared in Example 1, Example 2, Comparative Example 1, Comparative Example 2 and Comparative Example 3 were tested according to standard test strips. The performance test data results are shown in Table 1 below.

[0172] The compression set was tested according to GB / T7759.1-2015 "Determination of compression set of vulcanized rubber or thermoplastic rubber - Part 1: Under normal and high temperature conditions", with the following test conditions: type B specimen, compression rate 25%, 300℃×72h.

[0173] Peel strength was tested according to GB / T 7760-2003 "Determination of adhesion strength between vulcanized rubber or thermoplastic rubber and rigid sheet material - 90° peel method" under the following conditions: room temperature, 200℃×72h, and 280℃×72h.

[0174] Table 1 Performance test results of the sealing components

[0175]

[0176] As shown in Table 1, under the conditions of 300℃×72h and 25% compression ratio, the compression set of the perfluoroether rubber-metal composite seals provided in Examples 1 and 2 of this application is 28% and 27%, respectively. In contrast, the compression set of the perfluoroether rubber sealing layer prepared by peroxide vulcanization molding of perfluoroether rubber compound in Comparative Example 1 is 62%. This indicates that Examples 1 and 2 of this application have significantly better high-temperature compression set resistance than Comparative Example 1. In the peel strength test, tests were conducted at room temperature, 200℃×72h, and 280℃×72h. Comparative Example 2 showed debonding at 200℃×72h, while Comparative Example 1 and Comparative Example 3 also showed debonding at 280℃×72h. However, the peel strengths of Examples 1 and 2 of this application under the same conditions were 1.16 kN / m and 1.23 kN / m, respectively. This indicates that compared to Comparative Examples 1 to 3, the adhesive interfaces of Examples 1 and 2 of this application have higher adhesive strength and high-temperature durability.

[0177] Therefore, the perfluoroether rubber-metal composite seal and its preparation method provided in this application, through the synergistic effect of a specific rubber formulation, an optimized adhesive system, and the special surface morphology of the metal skeleton, enable the seal to possess excellent high-temperature compression set performance and adhesive interface durability in high-temperature environments below 300°C. This solves the problems of easy failure of sealing ability, poor adhesion effect and reliability of existing perfluoroether rubber-metal seals at high temperatures. It can be used stably for a long time in extreme high-temperature, strong oxidizing and corrosive media environments, and can meet the stringent requirements of ultra-high temperature long-term sealing in fields such as semiconductor manufacturing.

[0178] The above examples illustrate the present invention only to aid in understanding it and are not intended to limit the scope of the invention. Those skilled in the art can make various simple deductions, modifications, or substitutions based on the principles of this invention.

Claims

1. A perfluoroether rubber-metal composite seal, characterized in that, Includes a metal skeleton, a perfluoroether rubber sealing layer, and an adhesive layer; The metal skeleton has an adhesive bonding surface, the adhesive layer is disposed on the adhesive bonding surface, and the perfluoroether rubber sealing layer is bonded to the metal skeleton through the adhesive layer; The adhesive layer comprises a two-component adhesive; the bonding surface of the metal skeleton is a rough surface; and the perfluoroether rubber sealing layer is obtained by vulcanizing a cyano-cured perfluoroether rubber compound.

2. The perfluoroether rubber-metal composite seal according to claim 1, characterized in that, By weight, the cyano-cured perfluoroether rubber compound comprises the following components: 100 parts of perfluoroether rubber raw material; 15-25 parts of filler; Crosslinking agent 1.0~2.5 parts.

3. The perfluoroether rubber-metal composite seal according to claim 2, characterized in that, The perfluoroether rubber raw rubber includes tetrafluoroethylene, perfluoroalkyl vinyl ether, and a monomer with a vulcanization point. The sulfidation point monomer has a cyano group.

4. The perfluoroether rubber-metal composite seal according to claim 1, characterized in that, The dry film thickness of the adhesive layer is 7μm~10μm.

5. The perfluoroether rubber-metal composite seal according to claim 1, characterized in that, The surface roughness Ra of the bonding surface of the metal skeleton is 2μm~4.5μm.

6. The perfluoroether rubber-metal composite seal according to claim 1, characterized in that, The metal frame is the metal valve plate frame in a semiconductor heat treatment device.

7. A method for preparing a perfluoroether rubber-metal composite seal according to any one of claims 1 to 6, characterized in that, The preparation method of the perfluoroether rubber-metal composite seal includes: The bonding surfaces of the metal skeleton are roughened to form a rough surface; A two-component adhesive is applied to the roughened bonding surfaces to form the adhesive layer; A cyano-cured perfluoroether rubber compound is combined with a metal skeleton through an adhesive layer and then subjected to vulcanization molding to form a perfluoroether rubber sealing layer, thereby obtaining the perfluoroether rubber-metal composite seal.

8. The method for preparing the perfluoroether rubber-metal composite seal according to claim 7, characterized in that, The process involves combining a cyano-cured perfluoroether rubber compound with a metal skeleton via an adhesive layer, followed by vulcanization molding to form a perfluoroether rubber sealing layer, resulting in the perfluoroether rubber-metal composite seal. The cyano-cured perfluoroether rubber compound is combined with a metal skeleton through an adhesive layer and then subjected to compression molding and vulcanization to obtain an intermediate product. The intermediate product is subjected to a secondary vulcanization treatment to form a perfluoroether rubber sealing layer, thereby obtaining the perfluoroether rubber-metal composite seal.

9. The method for preparing the perfluoroether rubber-metal composite seal according to claim 8, characterized in that, The temperature of the compression molding vulcanization process is 160℃~170℃, and the pressure is 5MPa~12MPa.

10. The method for preparing the perfluoroether rubber-metal composite seal according to claim 8, characterized in that, The secondary vulcanization process includes the following steps: The vulcanization was carried out at a constant temperature for 1.5 hours, and then the temperature was increased to 70℃~90℃ at a rate of 1.5℃ / min~2℃ / min. The temperature was kept constant at 70℃~90℃ for 1.5h, and then the temperature was increased to 120℃~140℃ at a rate of 1.5℃ / min~2℃ / min. The temperature was kept constant at 120℃~140℃ for 1.5h, and then the temperature was increased to 170℃~190℃ at a rate of 1.5℃ / min~2℃ / min. The temperature was kept constant at 170℃~190℃ for 1.5h, and then the temperature was increased to 220℃~240℃ at a rate of 1.5℃ / min~2℃ / min. Vulcanization was carried out at a constant temperature of 220℃~240℃ for 16 hours.

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