A high temperature resistant perfluoroether elastomer composition and a method of making

Abstract

The application discloses a kind of high-temperature-resistant perfluoroether elastomer composition and preparation method, and the preparation method of high-temperature-resistant perfluoroether elastomer composition includes the following steps: S1, predetermined proportion of tetrafluoroethylene, perfluoromethyl vinyl ether, non-conjugated fluorine diene sulfur point monomer and phenyl-containing perfluorodiene sulfur point monomer and peroxide initiator emulsion polymerization obtain perfluoroether elastomer emulsion;S2, perfluoroether elastomer emulsion is condensed, washed, dried, and perfluoroether elastomer micro powder is obtained;S3, perfluoroether elastomer micro powder is mixed with predetermined proportion of filler, acid absorbent, vulcanizing agent and thin passage, and perfluoroether elastomer mixing rubber is obtained;S4, perfluoroether elastomer mixing rubber is molded by mould pressing, and secondary vulcanization obtains high-temperature-resistant, water-vapor-resistant perfluoroether elastomer composition.The perfluoroether elastomer composition prepared by the application has the characteristics of high-temperature resistance, water-vapor resistance and low compression permanent deformation.

Description

Technical Field

[0001] The present invention provides a high-temperature resistant perfluoroether elastomer composition and a preparation method thereof, which are applied in the field of semiconductor process technology. Background Art

[0002] Semiconductor manufacturing places extremely stringent demands on material performance, especially those that must maintain stable performance in high-temperature environments. Perfluoroether elastomers, due to their exceptional chemical stability, corrosion resistance, and high-temperature resistance, are ideal for sealing components in semiconductor manufacturing. However, existing perfluoroether elastomers still have room for improvement in terms of high-temperature resistance and compression set to better adapt to the increasingly complex advanced semiconductor manufacturing processes. Summary of the Invention

[0003] To address these issues, the present invention provides a high-temperature-resistant perfluoroether elastomer composition and preparation method. By introducing a phenyl-containing perfluorodiolefin as a vulcanization-site monomer, combined with specific polymerization and processing techniques, the high-temperature resistance of the perfluoroether elastomer is effectively improved while significantly reducing its compression set. This provides a superior material solution for semiconductor manufacturing processes, meeting the stringent high-temperature and high-precision requirements.

[0004] The first aspect of the present invention provides a method for preparing a high-temperature resistant perfluoroether elastomer composition containing a phenyl perfluorodiene vulcanization site monomer, comprising the following steps:

[0005] S1, emulsion polymerizing tetrafluoroethylene, perfluoromethyl vinyl ether, non-conjugated fluorodiene vulcanization monomer, phenyl-containing perfluorodiene vulcanization monomer and peroxide initiator in predetermined proportions to obtain a perfluoroether elastomer emulsion;

[0006] S2, coagulating, washing, and drying the perfluoroether elastomer emulsion to obtain perfluoroether elastomer powder;

[0007] S3, mixing the perfluoroether elastomer powder with a filler, an acid scavenger, and a vulcanizing agent in a predetermined proportion to obtain a perfluoroether elastomer rubber compound;

[0008] S4, molding the perfluoroether elastomer compound and performing secondary vulcanization to obtain a high-temperature-resistant and water vapor-resistant perfluoroether elastomer composition.

[0009] In one embodiment, the mass ratio of the tetrafluoroethylene: the perfluoromethyl vinyl ether: the non-conjugated fluorodiene vulcanization site monomer: the phenyl-containing perfluorodiene vulcanization site monomer: the peroxy initiator is 43-68: 30-55: 0.55-1.5: 0.55-1.5: 0.3-0.5.

[0010] In one embodiment, the non-conjugated fluorodiolefin curing site monomer is CH2=CH-(CF2) n -CH=CH2 (abbreviated as CnDVE) (n is an integer greater than or equal to 2), the perfluorodiene sulfur point monomer containing phenyl is CF2=CF-O-Ph-C(CF3)2-Ph-O-CF=CF2 (abbreviated as AFDVE), where Ph is phenyl.

[0011] In one embodiment, the filler is one of PTFE micropowder, PFA micropowder, fluorinated PI powder, carbon black, silica, or a mixture thereof; the filler accounts for 0-20% of the mass of the perfluoroether elastomer compound.

[0012] In one embodiment, in S2, drying comprises low-temperature freeze drying or vacuum drying.

[0013] In one embodiment, the acid scavenger is one of MgO, CaO, ZnO, PbO, dibasic lead phosphite or a mixture thereof, and the acid scavenger accounts for 0-10% of the mass of the perfluoroether elastomer compound.

[0014] In one embodiment, the vulcanizing agent is one of a non-conjugated fluorodiolefin curing site monomer, a phenyl-containing perfluorodiolefin curing site monomer, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, or a mixture thereof.

[0015] In one embodiment, the mass ratio of perfluoroether elastomer powder: non-conjugated fluorodiolefin vulcanization monomer: phenyl-containing perfluorodiolefin vulcanization monomer: bis(2-pentane) is 100: 0.55-1.5: 0.55-1.5: 1-2.

[0016] In one embodiment, in S3, a certain amount of non-conjugated fluorodiolefin vulcanization site monomer and phenyl-containing perfluorodiolefin vulcanization site monomer are first mixed and kneaded, and then dichlorodiphenylmethane is added and kneaded continuously.

[0017] In a second aspect, the present invention provides a high-temperature resistant perfluoroether elastomer composition, which is prepared using the above-mentioned method for preparing a high-temperature resistant perfluoroether elastomer composition.

[0018] Compared with the prior art, the at least one technical solution adopted in this embodiment can achieve the following beneficial effects:

[0019] This application obtains a perfluoroether elastomer by applying a phenyl-containing perfluorodiolefin vulcanization point monomer and a non-conjugated fluorodiolefin hyperbranching modification technology. The prepared perfluoroether elastomer composition has the characteristics of high temperature resistance and low compression permanent set, and can be applied to demanding advanced semiconductor processes.

[0020] This invention utilizes a phenyl-containing perfluorodiolefin vulcanization monomer to enhance its high-temperature resistance. The large π bond of the phenyl group disperses heat and electrons, slowing thermal decomposition. The phenyl-containing perfluorodiolefin maintains crosslinking stability at high temperatures. Bromine- or iodine-containing vulcanization monomers are no longer required, and CnDVE acts as a chain transfer agent, forming more stable crosslinks. By adjusting the ratio of the vulcanization monomer to the initiator, a moderately uniform crosslinking network is formed, avoiding either overcrowding that leads to embrittlement or oversparseness that leads to high-temperature deformation.

[0021] Compared with the prior art, the beneficial effects achieved by at least one of the above technical solutions adopted by the present invention include at least:

[0022] The invention obtains a perfluoroether elastomer by applying CnDVE and AFDVE hyperbranching modification technology. The prepared perfluoroether elastomer composition has the characteristics of high temperature resistance, water vapor resistance and low compression permanent deformation.

[0023] In the present invention, the specific processes of emulsion polymerization, mixing and thinning, compression molding, secondary vulcanization and the added vulcanizing agent are conventional processes in the industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying any creative work, other drawings obtained based on these drawings still fall within the scope of the present invention.

[0025] Figure 1 1 is a schematic diagram of the process for preparing the high-temperature resistant perfluoroether elastomer composition in the embodiment;

[0026] Figure 2 Schematic diagram of the sealing ring water vapor resistance test;

[0027] Figure 3 Infrared spectrum of AFDVE. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the objects, features and advantages of the present invention can be more clearly understood. It should be understood that the embodiments shown in the accompanying drawings are not intended to limit the scope of the present invention, but are only intended to illustrate the essential spirit of the technical solutions of the present invention.

[0029] In the following description, for the purpose of illustrating the various disclosed embodiments, certain specific details are set forth in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the relevant art will recognize that the embodiments may be practiced without one or more of these specific details. In other cases, well-known devices, structures, and techniques associated with this application may not be shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0030] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any manner in one or more embodiments.

[0031] In the following description, in order to clearly show the structure and working mode of the present invention, many directional words will be used for description, but words such as "front", "back", "left", "right", "outside", "inside", "outward", "inward", "up", and "down" should be understood as convenient terms and should not be understood as restrictive terms.

[0032] It should be noted that the features shown in the drawings of this application may belong to one embodiment or to different embodiments, as long as there is no conflict between these features. To save space, this application may use the same drawing to illustrate different embodiments. In other words, the same drawing of this application can be used to illustrate features of different embodiments.

[0033] The molecular structure of phenyl-containing perfluorodiolefin vulcanization monomers (AFDVEs) is characterized by a high degree of stability, and their large π-bond system disperses electrons, enhancing molecular stability. These stable chemical bonds and structures resist breakage and decomposition in high-temperature environments, enhancing the high-temperature and water vapor resistance of perfluoroether elastomers and their compositions, maintaining excellent physical and chemical properties in high-temperature processes such as semiconductor manufacturing.

[0034] The cross-linked structure formed by the vulcanization monomer during the vulcanization process significantly affects the compression set of elastomers. Non-conjugated fluorodiolefin vulcanization monomers (CnDVE) and AFDVE form a uniform and moderate cross-linked network. This cross-linked network effectively limits molecular chain slippage and deformation. When the elastomer is subjected to compression, the cross-linked structure stores energy, allowing the elastomer to return to its original shape after the pressure is removed, thereby reducing compression set and ensuring that the elastomer maintains good sealing properties and elasticity during long-term use.

[0035] The two kinds of vulcanization point monomers can effectively vulcanize with peroxide initiator and the like to form chemical crosslinking. The reaction activity of CnDVE is moderate, and the polymerization and vulcanization reaction with other monomers can be carried out under suitable conditions to control the crosslinking speed and degree. The phenyl group in AFDVE can affect the active center and reaction path of the reaction, making the vulcanization reaction more controllable, and being conducive to the preparation of full fluorinated ether elastomer and composition with stable performance.

[0036] The fluorine-containing polymers obtained by free radical polymerization reaction are difficult to control the molecular weight and molecular weight distribution due to the coupling termination and disproportionation termination of free radicals. The high energy of C-F bond prevents the branching reaction of polymer chains, so the fluoropolymer with high fluorine content is basically linear. Although linear polymers can provide better flowability and physical properties in many cases, polymers with complex chain structures such as star-shaped and block copolymers are more marketable due to their other excellent properties.

[0037] The peroxide vulcanized fluorine elastomer in the prior art is obtained by introducing a "vulcanization point" monomer susceptible to free radical attack into the macromolecule. For example, the high-energy C-I bond is used for peroxide vulcanization system, and the iodine end group of the polymer chain can be used to vulcanize the elastomer. Notably, the mechanical stability of the crosslinking network is related to the number of end groups on each macromolecule, and the more the number is, the better the mechanical properties of the crosslinking network are. When using such "vulcanization point" monomer technology, the number of end groups on each macromolecular chain is less than 2, and the vulcanized rubber obtained in this way is relatively poor in mechanical properties and compression set resistance, which cannot meet the growing demand for processing of vulcanized rubber.

[0038] Branching technology can synthesize a series of products with different structural characteristics to meet different application needs, such as peroxide vulcanizable fluorine elastomer and fluorine-containing thermoplastic elastomer. In all cases, it is always desirable to have as many end groups as possible on each macromolecule, and branching technology can achieve this. A small amount of highly active fluorodiene used as a vulcanization point monomer in the reaction medium can form polymers with complex chain structures such as star-shaped and block copolymers. Because fluorodiene is active, it can quickly and completely connect to the growing chain once it is added, so that the number of end groups on each macromolecular chain is much higher than 2, and these polymers have better mechanical properties and sealing performance after a very short press vulcanization and secondary vulcanization process.

[0039] However, there are still some aspects to be improved. First, the non-conjugated fluorodiene and phenyl-containing perfluorodiene hyperbranching modification technology is applied to perfluoroether elastomer, so that the prepared perfluoroether elastomer composition has the characteristics of high temperature resistance, water vapor resistance and low compression permanent deformation; second, the problem of poor stability of the end groups of the hyperbranched modified perfluoroether elastomer composition is solved to be applied to harsh advanced semiconductor processes.

[0040] Based on this, Figure 1 As shown, this embodiment provides a method for preparing a high-performance perfluoroether elastomer composition using a hyperbranched modified non-conjugated fluorodiolefin and a phenyl-containing perfluorodiolefin vulcanization site monomer, comprising the following steps:

[0041] S1, emulsion polymerizing 43-68 parts by mass of tetrafluoroethylene, 30-55 parts by mass of perfluoroalkyl vinyl ether, 0.3-0.5 parts by mass of peroxy initiator, 0.55-1.5 parts by mass of non-conjugated fluorodiolefin vulcanization monomer, and 0.55-1.5 parts by mass of phenyl-containing perfluorodiolefin vulcanization monomer to obtain a perfluoroether elastomer emulsion;

[0042] S2, coagulating, washing, drying, devolatilizing and end-group passivating the perfluoroether elastomer emulsion to obtain perfluoroether elastomer powder;

[0043] S3, mixing the perfluoroether elastomer powder with a filler, an acid scavenger, and a vulcanizing agent at 60-90° C. to obtain a perfluoroether elastomer rubber compound;

[0044] S4. The perfluoroether elastomer compound is molded and subjected to secondary vulcanization to obtain a perfluoroether elastomer composition that is resistant to high temperature and water vapor and has low compression set.

[0045] Optionally, the non-conjugated fluorodiolefin curing site monomer structure is CH2=CH-(CF2) n -CH=CH2 (abbreviated as CnDVE) (n is an integer greater than or equal to 2).

[0046] Optionally, the structure of the phenyl-containing perfluorodiene vulcanization site monomer is CF2=CF-O-Ph-C(CF3)2-Ph-O-CF=CF2 (abbreviated as AFDVE), wherein Ph is a phenyl group.

[0047] Alternatively, the perfluoroalkyl vinyl ether includes one or more of perfluoromethyl vinyl ether, perfluoroethyl vinyl ether, and perfluoropropyl vinyl ether.

[0048] Optionally, the filler is at least one of PTFE micropowder, PFA micropowder, fluorinated PI powder, carbon black, or silicon dioxide; and the filler accounts for 0-20% of the mass of the perfluoroether elastomer compound.

[0049] Optionally, in S2, drying includes low-temperature drying or vacuum drying.

[0050] Optionally, the acid scavenger is one or more of MgO, CaO, ZnO, PbO, and dibasic lead phosphite, and the acid scavenger accounts for 0-10% of the mass of the perfluoroether elastomer compound.

[0051] Optionally, the vulcanizing agent is one or more of CnDVE, AFDVE, and 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane (DBPH).

[0052] Optionally, a certain amount of CnDVE and AFDVE are mixed first, and then the double 25 is added and the mixing is continued.

[0053] Optionally, in S1, the non-conjugated fluorodiolefin vulcanization site monomer is added in stages or continuously during the polymerization process.

[0054] Preparation of phenyl-containing perfluorodiene vulcanization site monomer (AFDVE; Cas # 134174-11-1; molecular weight 496.25)

[0055] To a 1 L five-necked round-bottom flask equipped with an addition funnel, reflux condenser, receiver, and mechanical stirrer, 190.1 g (0.57 mol) of bisphenol AF starting material, 63.3 g (0.57 mol) of potassium tert-butoxide (CH3)3COK, 31.5 g (0.57 mol) of KOH, and 450 mL of dimethyl sulfoxide (DMSO) were added. The temperature was raised to 120°C and the mixture was refluxed under vacuum for 30 hours. The product was dried by azeotropic distillation under reduced pressure and washed with dry DMSO (dimethyl sulfoxide). The temperature was lowered to 30°C, and 325 g (1.17 mol) of BrCF2CF2Br (tetrafluorodibromoethane) was added dropwise over 4 hours. The mixture was heated to room temperature (25°C) for 12 hours and then heated to 35°C for 12 hours. The reaction was quenched by adding water, extracted with dichloromethane, and the organic phase was washed three times with water, dried over MgSO4, and concentrated in vacuo to obtain 200 g of the supernatant intermediate; the intermediate was purified by refluxing with alumina in hexane.

[0056] 37.5 g (0.057 mol; MW 658.07) of the intermediate was added to a 1 L dry three-necked round-bottom flask. 10.5 g (0.162 mol; MW 65) of Zn powder and 45 ml of anhydrous acetonitrile MeCN were added at 80 °C. The mixture was refluxed for 15 h to obtain the product AFDVE. AFDVE was purified by refluxing alumina in hexane to obtain 13.7 g of the purified transparent product AFDVE (yield 53%).

[0057] The corresponding reaction mechanism is shown in the reaction equation below.

[0058]

[0059] In the formula, 1 is the molecular structure of bisphenol AF, 2 is the molecular structure of the intermediate, and 3 is the molecular structure of the product.

[0060] Infrared spectra are obtained by analyzing the absorption of infrared light by substances. Different chemical bonds or functional groups have selective absorption of infrared light, which makes infrared spectroscopy an important tool for studying molecular structure.

[0061] The infrared spectrum of AFDVE is shown in Figure 3 (Shimadzu FTIR AIM-9000), infrared spectra are usually expressed in wave numbers (unit: cm -1 ), the horizontal axis represents the wave number, and the vertical axis represents the transmittance or absorbance.

[0062] Each peak on the spectrum corresponds to the vibration absorption of a certain chemical bond or functional group in the molecule. By analyzing the position, shape and intensity of these peaks, the structural information of the molecule can be inferred. -1 、1610.56 cm -1 is the skeleton vibration of the benzene ring, 1832.38 cm -1 is the stretching vibration of CF2=CF, 1170.79 cm -1 It is the absorption peak of -CF3 group.

[0063] CnDVE and AFDVE work synergistically with the dipentadienyl vulcanizing agent to provide moderate reactivity, ensuring a controlled crosslinking rate and preventing material embrittlement caused by overly rapid vulcanization. The stabilizing effect of the phenyl groups creates highly stable crosslinking points, enhancing the durability of the network structure at high temperatures.

[0064] The dipentadiene disulfide vulcanizing agent can provide stable and controllable vulcanization efficiency. CnDVE and AFDVE enhance the high temperature resistance and chemical corrosion resistance of the final product. In the manufacturing of high temperature and high pressure seals, their synergy can balance the safety of the vulcanization process and the durability of the final product.

[0065] Example 1

[0066] S1, 434 g (about 4.34 mol; 54.3% by mass) tetrafluoroethylene (MW 100.01), 347 g (about 2.09 mol; 43.4% by mass) perfluoromethyl vinyl ether (MW 166.02), 7.5 g (about 0.03 mol; 1.05% by mass) non-conjugated fluorodiolefin vulcanization monomer CH2=CH-(CF2)4-CH=CH2 (MW 254.12), 7.5 g (about 0.015 mol; 1.05% by mass) phenyl-containing perfluorodiolefin vulcanization monomer CF2=CF-O-Ph-C(CF3)2-Ph-O-CF=CF2 (MW 496.25), 3.34 g initiator ammonium persulfate (APS) was used for emulsion polymerization to obtain a hyperbranched modified perfluoroether elastomer emulsion; non-conjugated fluorodiolefin curing point monomer was added in batches by a metering pump at the beginning and end of the reaction, 0.75 g each time, for a total of 10 times.

[0067] S2. After flocculation with HNO3, washing and drying, about 686 g of perfluoroether elastomer powder was obtained.

[0068] S3. Mix 5 g of CnDVE and 5 g of AFDVE, and knead them with 500 g of perfluoroether elastomer powder at 60-90 °C for a thin layer, then add 10 g of dipentadienyl vulcanizing agent and continue kneading for a thin layer to obtain a perfluoroether elastomer compound rubber.

[0069] S4. The mixed rubber is molded and subjected to secondary vulcanization to obtain a hyperbranched modified perfluoroether elastomer composition (O-ring).

[0070] Example 2

[0071] A hyperbranched perfluoroether elastomer emulsion was prepared by emulsion polymerization of 400 g (approximately 4.0 mol; 51.1% by mass) tetrafluoroethylene (MW 100.01), 360 g (approximately 2.17 mol; 46.0% by mass) perfluoromethyl vinyl ether (MW 166.02), 10 g (approximately 0.039 mol; 1.28% by mass) non-conjugated fluorodiene CH2=CH-(CF2)4-CH=CH2 (MW 254.12), 10 g (approximately 0.02 mol; 1.28% by mass) AFDVE monomer CF2=CF-O-Ph-C(CF3)2-Ph-O-CF=CF2 (MW 496.25), and 3.34 g initiator ammonium persulfate (APS). The non-conjugated fluorodiene was added in batches of 1 g each time at the beginning and end of the reaction, for a total of 10 times.

[0072] S2. After flocculation with HNO3, washing and drying, about 634 g of perfluoroether elastomer powder was obtained.

[0073] S3. Mix 5 g of CnDVE and 5 g of AFDVE, and knead them with 500 g of perfluoroether elastomer powder at 60-90°C for a thin layer, then add 10 g of dipentadienyl vulcanizing agent and continue kneading for a thin layer to obtain a perfluoroether elastomer compound rubber.

[0074] S4. Molding the mixed rubber and performing secondary vulcanization to obtain a hyperbranched modified perfluoroether elastomer composition and an O-ring.

[0075] Comparative Example 1

[0076] S1. 434 g (about 4.34 mol; 54.3% by mass) of tetrafluoroethylene (MW 100.01), 347 g (about 2.1 mol; 43.4% by mass) of perfluoromethyl vinyl ether (MW 166.02), 3.34 g of initiator ammonium persulfate (APS), and 15 g (about 0.04 mol; 1.85% by mass) of non-conjugated fluorodiolefin CH2=CH-(CF2)4-CH=CH2 (MW 254.12) were emulsion polymerized to obtain a hyperbranched modified perfluoroether elastomer emulsion; the non-conjugated fluorodiolefin was added in batches of 1.5 g each time by a metering pump at the beginning and end of the reaction, for a total of 10 times.

[0077] S2. After flocculation with HNO3, washing and drying, about 713 g of perfluoroether elastomer powder was obtained.

[0078] S3. Mix 500 g of perfluoroether elastomer powder and 10 g of dipentadienyl vulcanizing agent at 60-90° C. to obtain a perfluoroether elastomer compound rubber.

[0079] S4. The mixed rubber is molded and subjected to secondary vulcanization to obtain a hyperbranched modified perfluoroether elastomer composition and an O-ring.

[0080] Comparative Example 2

[0081] A hyperbranched modified perfluoroether elastomer emulsion was obtained by emulsion polymerization of 400 g (about 4.0 mol; 51.1% by mass) of tetrafluoroethylene (MW 100.01), 360 g (about 2.17 mol; 46.0% by mass) of perfluoromethyl vinyl ether (MW 166.02), 3.3 g of initiator ammonium persulfate (APS), and 20 g (about 0.047 mol; 2.55% by mass) of non-conjugated fluorodiolefin CH2=CH-(CF2)4-CH=CH2 (MW 254.12). The non-conjugated fluorodiolefin was added in batches of 2 g each time at the beginning and end of the reaction by a metering pump for a total of 10 times.

[0082] S2. After flocculation with HNO3, washing and drying, about 720 g of perfluoroether elastomer powder was obtained.

[0083] S3. Mix 500 g of perfluoroether elastomer powder and 10 g of dipentadienyl vulcanizing agent at 60-90° C. to obtain a perfluoroether elastomer compound rubber.

[0084] S4. The mixed rubber is molded and subjected to secondary vulcanization to obtain a hyperbranched modified perfluoroether elastomer composition and an O-ring.

[0085] Table 1 Main test results of this embodiment and comparative example

[0086]

[0087] The hydrothermal synthesis reactor for heat resistance (superheated steam) experiment is used as a sealed container.

[0088] like Figure 2 As shown, a reactor 1 serving as a sealed container has a water vapor-resistant lining 2 with a capacity of 100 ml. Deionized water 3 (resistivity ≥ 18.2 MΩ·cm) is added to about 1 / 3 of the liquid level of the lining 2 to carry out a hydrothermal synthesis reaction. Samples YP of the same size (Φ3.53 mm) are taken from Examples 1 and 2 and Comparative Examples 1 and 2. A polytetrafluoroethylene wire 4 is used to hover above the deionized water 3 and heat the sample to about 95°C. After the air is removed, the reactor 1 is sealed and placed in an oven. A constant temperature heat source is given at 200°C (saturated vapor pressure of 15.57 bar). After 72 hours, the sample YP is removed from the oven for testing and comparison. The test results are shown in Table 2.

[0089] Table 2 Heat resistance (superheated steam) test results of examples and comparative examples

[0090]

[0091] *Senhuan Enterprise Standard Perfluoroether Elastomer and Rubber Seal Immersion and Liquid Resistance Test Method

[0092] A comparison of Examples 1 and 2 with Comparative Examples 1 and 2 in Tables 1 and 2 shows that the values ​​of the line diameter change rate and the mass change rate of Examples 1 and 2 are much smaller than those of Comparative Examples 1 and 2. In this example, a perfluoroether elastomer is obtained by applying a hyperbranched modification technology of a non-conjugated fluorodiene CnDVE and a phenyl sulfide point-containing AFDVE monomer. The prepared perfluoroether elastomer composition has the characteristics of high temperature resistance, water vapor (steam), and low compression set, and can be applied to demanding semiconductor processes.

[0093] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0094] The embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and all changes that come within the meaning and range of equivalents of the claims are therefore intended to be embraced therein.

[0095] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, system or module that includes a series of elements includes not only those elements, but also other elements that are not explicitly listed, or elements that are inherent to such process, method, system or module. In the absence of further restrictions, an element defined by the sentence "comprises a..." does not exclude the presence of other identical elements in the process, method, system or module that includes the element.

[0096] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but is to be construed in the widest possible manner consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a high-temperature resistant perfluoroether elastomer composition, characterized in that: The following steps are involved: S1. Emulsion polymerizing tetrafluoroethylene, perfluoromethyl vinyl ether, a non-conjugated fluorodiolefin vulcanization monomer, a phenyl-containing perfluorodiolefin vulcanization monomer, and a peroxide initiator to obtain a perfluoroether elastomer emulsion, wherein the phenyl-containing perfluorodiolefin vulcanization monomer is CF2=CF-O-Ph-C(CF3)2-Ph-O-CF=CF2, wherein Ph is a phenyl group; S2, coagulating, washing, and drying the perfluoroether elastomer emulsion to obtain perfluoroether elastomer powder; S3, mixing the perfluoroether elastomer powder with a filler, an acid scavenger, and a vulcanizing agent in a predetermined proportion to obtain a perfluoroether elastomer rubber compound; S4, molding the perfluoroether elastomer compound and performing secondary vulcanization to obtain a high-temperature-resistant and water vapor-resistant perfluoroether elastomer composition.

2. The method for preparing a high temperature resistant perfluoroether elastomer composition according to claim 1, wherein: The mass ratio of the tetrafluoroethylene: the perfluoromethyl vinyl ether: the non-conjugated fluorodiene vulcanization site monomer: the phenyl-containing perfluorodiene vulcanization site monomer: the peroxy initiator is 43-68: 30-55: 0.55-1.5: 0.55-1.5: 0.3-0.

5.

3. The method for preparing a high temperature resistant perfluoroether elastomer composition according to claim 1 or 2, characterized in that: The non-conjugated fluorodiolefin curing point monomer is CH2=CH-(CF2) n -CH=CH2, where n is an integer greater than or equal to 2.

4. The method for preparing a high temperature resistant perfluoroether elastomer composition according to claim 1, wherein: The filler is one of PTFE micropowder, PFA micropowder, fluorinated PI powder, carbon black and silicon dioxide or a mixture thereof; the filler accounts for 0-20% of the mass of the perfluoroether elastomer compound.

5. The method for preparing a high temperature resistant perfluoroether elastomer composition according to claim 1, wherein: In S2, drying includes low-temperature freeze drying or vacuum drying.

6. The method for preparing a high temperature resistant perfluoroether elastomer composition according to claim 1, wherein: The acid absorber is one of MgO, CaO, ZnO, PbO and dibasic lead phosphite or a mixture thereof.

7. The method for preparing a high temperature resistant perfluoroether elastomer composition according to claim 1, wherein: The vulcanizing agent is one of a non-conjugated fluorodiolefin vulcanization site monomer, a phenyl-containing perfluorodiolefin vulcanization site monomer, and 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, or a mixture thereof.

8. The method for preparing a high temperature resistant perfluoroether elastomer composition according to claim 7, wherein: The mass ratio of the perfluoroether elastomer powder: the non-conjugated fluorodiolefin vulcanization site monomer: the phenyl-containing perfluorodiolefin vulcanization site monomer: bis(2-pentane) is 100: 0.55-1.5: 0.55-1.5: 1-2.

9. The method for preparing a high temperature resistant perfluoroether elastomer composition according to claim 7, wherein: In S3, the non-conjugated fluorodiolefin vulcanization site monomer and the phenyl-containing perfluorodiolefin vulcanization site monomer are first mixed and kneaded, and then dichloromethane is added and kneaded continuously.

10. A high temperature resistant perfluoroether elastomer composition, characterized in that: The high-temperature resistant perfluoroether elastomer composition is prepared by the preparation method of any one of claims 1 to 9.

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