A fluorine rubber composition of a new vulcanization system and a method for preparing the same

Abstract

The application provides a fluororubber composition of a new vulcanization system and a preparation method thereof, and the fluororubber composition is obtained by introducing a comonomer into a vulcanization system to perform a polymerization reaction to obtain a fluororubber emulsion; wherein the comonomer comprises tetrafluoroethylene, vinylidene fluoride and perfluoroalkyl vinyl ether; the vulcanization system comprises deoxygenated deionized water, an emulsifier, an initiator and a vulcanization point monomer; the fluororubber emulsion is condensed, washed, dried and plasticated to obtain fluororubber raw rubber; and the fluororubber raw rubber, fillers and auxiliaries are mixed to obtain the fluororubber composition. The application can realize a new in-situ crosslinking method without a vulcanizing agent, and a double bond is generated by thermal cracking of the vulcanization point monomer in the fluororubber under catalysis, thermal crosslinking occurs between the double bonds at high temperature to form a three-dimensional network structure, in-situ vulcanization of the fluororubber is realized, and a new fluororubber composition is obtained.

Description

Technical Field

[0001] This application relates to the field of fluororubber production technology, and in particular to a novel vulcanization system of fluororubber composition and its preparation method. Background Technology

[0002] Fluororubber (FKM), due to the presence of fluorine atoms in its molecular structure, possesses excellent high-temperature resistance, oil resistance, chemical corrosion resistance, and weather resistance, making it widely used in aerospace, automotive, and petrochemical industries. Traditional vulcanization methods for fluororubber primarily rely on peroxide or bisphenol systems. Peroxide crosslinking requires high-temperature, long-duration vulcanization and may produce toxic byproducts; bisphenol crosslinking is complex and costly. These vulcanization methods not only limit the processing efficiency of fluororubber but may also affect its long-term stability. Summary of the Invention

[0003] This application aims to at least partially solve one of the technical problems in the related art. This application proposes a novel vulcanization system for fluororubber compositions and its preparation method. This application achieves a novel in-situ crosslinking method without the need for a vulcanizing agent. Under catalysis, the monomers at the vulcanization points in the fluororubber undergo thermal decomposition to generate double bonds. At high temperature, thermal crosslinking occurs between the double bonds to form a three-dimensional network structure, achieving in-situ vulcanization of the fluororubber and obtaining a novel fluororubber composition with good mechanical strength.

[0004] According to the embodiments of the first aspect of this application, a method for preparing a novel vulcanized fluororubber composition is provided, comprising the following steps:

[0005] A fluororubber latex is obtained by passing comonomers into a vulcanization system for polymerization; wherein the comonomers include tetrafluoroethylene, vinylidene fluoride, and perfluoroalkyl vinyl ethers; and the vulcanization system includes deoxygenated deionized water, emulsifier, initiator, and vulcanization point monomer. The fluororubber emulsion is coagulated, washed, dried, and plasticized to obtain raw fluororubber. The fluororubber raw rubber, fillers, and additives are mixed to obtain a fluororubber composition.

[0006] In some embodiments, the perfluoroalkyl vinyl ether is selected from at least one of perfluoromethyl vinyl ether, perfluoroethyl vinyl ether, and perfluoropropyl vinyl ether; And / or, based on the comonomer, the perfluoroalkyl vinyl ether comprises 20-45% by weight.

[0007] In some embodiments, the emulsifier is selected from at least one of perfluorocarboxylate, perfluoroether carboxylate, and perfluorosulfonate; And / or, based on the comonomer, the amount of the emulsifier is 0.01-5% by mass percentage.

[0008] In some embodiments, the initiator is selected from at least one of potassium persulfate, sodium persulfate, and ammonium persulfate; And / or, based on the comonomer, the amount of the initiator is 0.01-5% by mass percentage.

[0009] In some embodiments, the general formula of the sulfurization point monomer is CX1X2=CX3X4-Y-COOM; Wherein X1-X4 are H or F; Y is selected from one or more of alkyl, perfluoroalkyl, or partially fluoroalkyl, alkoxy, and polyether; wherein M is selected from at least one of Na, K, Ca, Mg, and NH4. And / or, by mass percentage, the amount of the vulcanization point monomer based on the comonomer is 0.01-5%.

[0010] In some embodiments, the polymerization reaction pressure is 1.4-4.0 MPa, the temperature is 60-100℃, the polymerization time is 2-12 h, and the stirring speed during polymerization is 200-1000 rpm.

[0011] In some embodiments, the filler is selected from at least one of carbon black, silica, calcium carbonate, and talc. And / or, based on the raw fluororubber, the amount of filler is 10-30% by mass percentage.

[0012] In some embodiments, the additive is at least one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol methyl ethyl ether; And / or, based on the raw fluororubber, the amount of the additive is 0.5-10% by mass percentage.

[0013] In some embodiments, the mixing temperature is 60-160℃ and the mixing time is 0.5-6min.

[0014] According to an embodiment of the second aspect of this application, a novel vulcanization system fluororubber composition is provided, which is obtained using the preparation method described in any of the above embodiments.

[0015] The present application discloses a novel vulcanization system for fluororubber compositions and its preparation method, which has the following beneficial effects: The present application introduces novel vulcanization point monomers into the fluororubber molecular chain, wherein the carboxylate groups are thermally decomposed under catalysis to generate double bonds, and thermal cross-linking occurs between the double bonds at high temperature, thereby realizing in-situ vulcanization of fluororubber without the need to add vulcanizing agents during the vulcanization process.

[0016] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0017] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a flowchart of a method for preparing a novel vulcanization system fluororubber composition according to embodiments of this application. Detailed Implementation

[0018] Embodiments of this application are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. Rather, this application includes all variations, modifications, and equivalents falling within the spirit and scope of the appended claims.

[0019] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0020] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0021] According to the embodiments of the first aspect of this application, a method for preparing a novel vulcanized fluororubber composition is provided as follows: Figure 1 As shown, it includes the following steps: S1: A fluororubber latex is obtained by passing comonomers into a vulcanization system for polymerization; wherein the comonomers include tetrafluoroethylene, vinylidene fluoride and perfluoroalkyl vinyl ethers; the vulcanization system includes deoxygenated deionized water, emulsifier, initiator and vulcanization point monomer; S2: Fluororubber raw rubber is obtained by coagulating, washing, drying and plasticizing fluororubber emulsion; S3: Fluororubber composition is obtained by mixing raw fluororubber, fillers and additives.

[0022] In step S1, the comonomer is introduced into the vulcanization system to carry out a polymerization reaction to obtain a fluororubber emulsion; wherein the comonomer includes tetrafluoroethylene, vinylidene fluoride and perfluoroalkyl vinyl ether; the content of perfluoroalkyl vinyl ether is 20-45% by mass percentage based on the comonomer.

[0023] For example, the perfluoroalkyl vinyl ether is selected from at least one of perfluoromethyl vinyl ether, perfluoroethyl vinyl ether, and perfluoropropyl vinyl ether, and the content of the perfluoroalkyl vinyl ether, based on the comonomer, is 20%, 25%, 28%, 30%, 32%, 35%, 39%, 40%, or 45% by mass percentage. In some embodiments, if the content of the perfluoroalkyl vinyl ether is too low, such as less than 20%, the elasticity and compressive properties of the fluororubber product decrease, and it is prone to brittleness at low temperatures; when the content of the perfluoroalkyl vinyl ether is too high, such as greater than 45%, the mechanical properties and heat resistance of the fluororubber product decrease. In some embodiments, the molar percentage of tetrafluoroethylene, vinylidene fluoride, and perfluoromethyl vinyl ether is 45:25:30.

[0024] In this process, the vulcanization system includes deoxygenated deionized water, emulsifier, initiator, and vulcanization point monomer; wherein the emulsifier is selected from at least one of perfluorocarboxylate, perfluoroether carboxylate, and perfluorosulfonate; the amount of emulsifier used is 0.01-5% by mass percentage, based on the comonomer.

[0025] The general structural formula of the example perfluorocarboxylate is CF3(CF2). n COO - M + Where n takes values ​​from 3 to 13, M + It is a cation, such as Na + NH4 + Examples include perfluorooctanoic acid, perfluorohexanoic acid, perfluorononanoic acid, perfluorodecanoic acid, and ammonium perfluorooctanoate. The general structural formula of perfluoroether carboxylates is CF3OCF2CF2CF2COO.- M + M + It is a cation, such as Na + NH4 + For example, it includes hexafluoropropylene oxide dimer acid, ADONA, PFO2H x A, PFO3OA, etc. The general structural formula for perfluorosulfonates is CF3(CF2). n SO3 - M + n is 3-8, M + It is a cation, such as Na + NH4 + Examples of emulsifiers include perfluorooctane sulfonic acid, perfluorohexane sulfonic acid, and perfluorobutane sulfonic acid. Based on the comonomer, the emulsifier content is 0.01%, 0.05%, 0.1%, 1%, 2%, 3%, 4%, or 5% by mass percentage. In some embodiments, if the emulsifier content is too low, such as less than 0.01%, demulsification will easily occur during the reaction, affecting the polymerization rate and conversion rate. In other embodiments, if the emulsifier content is too high, such as greater than 5%, it will lead to low purity of the fluororubber product, significantly increase the cost of post-processing, and residual emulsifier will affect the performance of the vulcanized product.

[0026] In some embodiments, the initiator is selected from at least one of potassium persulfate, sodium persulfate, and ammonium persulfate; the initiator dosage, based on the comonomer, is 0.01-5% by mass percentage, with examples of 0.01%, 0.05%, 0.1%, 1%, 2%, 3%, 4%, or 5% based on the comonomer. In some embodiments, if the initiator dosage is too low, such as less than 0.01%, it results in a slow polymerization rate, low conversion rate, and uneven molecular weight distribution of the fluororubber product; in some embodiments, if the initiator content is too high, such as greater than 5%, the fluororubber product has a low molecular weight and poor strength of the vulcanized product.

[0027] In some embodiments, the general formula of the vulcanizing point monomer is CX1X2=CX3X4-Y-COOM; wherein X1-X4 are H or F; Y is selected from one or more of alkyl, perfluoroalkyl, or partially fluoroalkyl, alkoxy, and polyether; wherein M is selected from at least one of Na, K, Ca, Mg, and NH4, for example, the vulcanizing point monomer is CF2=CF(CF2)4COONa. Based on the comonomer, the amount of vulcanizing point monomer used is 0.01%, 0.05%, 0.1%, 1%, 2%, 3%, 4%, or 5% by mass percentage. In some embodiments, if the amount of vulcanizing point monomer is too small, such as less than 0.01%, the vulcanization speed of the fluororubber product is too slow, and the mechanical properties and heat resistance properties decrease. In some embodiments, if the content of vulcanizing point monomer is too large, such as greater than 5%, the vulcanization speed of the fluororubber product is too fast, making it prone to scorching; the elasticity and compression set properties decrease, and the processing performance deteriorates.

[0028] In this process, the polymerization reaction pressure is 1.4-4.0 MPa, the temperature is 60-100℃, the polymerization time is 2-12 h, and the stirring speed is 200-1000 rpm. For example, deoxygenated deionized water can be added to the reactor, and TFE can be used to replace the air in the reactor, so that the oxygen content in the reactor is ≤10 ppm and the nitrogen concentration is ≤1.0%. The reactor is heated to 90℃, and the comonomer (tetrafluoroethylene:vinylidene fluoride: perfluoromethyl vinyl ether = 45:25:30 mol%) is added to the reactor using a diaphragm compressor. After the pressure reaches 2.2 MPa, stirring is started at a speed of 200-1000 rpm. Emulsifier, deionized water, sulfurization point monomer, and initiator are added to the reactor to start the reaction. In addition, during the reaction process, comonomers are continuously introduced and the pressure in the reactor is maintained at 1.4-4.0 MPa, the temperature is maintained at 60-100℃, the stirring speed is 200-1000 rpm, and the reaction is carried out until the predetermined feed amount is reached. The polymerization time is 2-12 hours to obtain fluororubber emulsion.

[0029] In step S2, the fluororubber emulsion is coagulated, washed, dried, and plasticized to obtain fluororubber raw rubber. The coagulation, washing, drying, and plasticizing of the perfluoroether rubber emulsion are carried out using conventional processes in the field. For example, the coagulation of the perfluoroether rubber emulsion is carried out using the electrolyte coagulation method. Under stirring, a coagulant solution, such as an aqueous solution of calcium chloride, magnesium chloride, aluminum sulfate, or polyaluminum chloride, is slowly added to the diluted perfluoroether rubber emulsion. The temperature is usually controlled at 30-60°C to reduce viscosity and promote coagulation.

[0030] The washing process in this procedure involves multi-stage countercurrent washing and coagulation, followed by separation of most of the water from the wet rubber particles using a vibrating screen, inclined screen, or centrifuge. The wet rubber particles are then redispersed in deionized water to form a slurry, which is then agitated and washed repeatedly in a countercurrent manner. This means the freshest deionized water is used for the final washing stage, and the wash water is reused from stage to stage to improve efficiency and reduce water consumption. The drying process first uses mechanical dehydration to reduce the moisture content of the wet rubber to 10-30%, followed by a fluidized bed dryer or vibrating fluidized bed dryer. The plasticizing process is carried out using a two-roll mill, with the roll temperature generally controlled between 30-60℃. Multiple cutting and folding operations are required to ensure uniform plasticizing.

[0031] In step S3, the fluororubber raw rubber, filler, and additives are mixed to obtain a fluororubber composition. The filler is selected from at least one of carbon black, silica, calcium carbonate, and talc; the filler content, based on the fluororubber raw rubber, is 10-30% by mass percentage. Examples of filler content include 10%, 15%, 18%, 22%, 25%, 28%, 29%, or 30%. In some embodiments, when the filler content is too low, such as less than 10%, the mechanical properties of the fluororubber composition decrease; conversely, in some embodiments, when the filler content is too high, such as greater than 30%, the mechanical properties of the fluororubber composition also decrease, and the processing performance deteriorates.

[0032] In this application, the additive is at least one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol methyl ethyl ether; the amount of additive based on fluororubber raw rubber, by mass percentage, is 0.5-10%. Examples of additive amounts are 0.5%, 1%, 2%, 3%, 4%, 6%, 8%, or 10%, etc. In some embodiments, if the amount of additive is too small, such as less than 0.5%, the vulcanization speed of the fluororubber product is too slow, and the mechanical properties and heat resistance decrease. In some embodiments, if the content of the additive is too large, such as greater than 10%, the vulcanization speed of the fluororubber product is too fast, making it prone to scorching; the elasticity and compression set properties decrease, and the processing performance deteriorates.

[0033] The process involves mixing raw fluororubber with fillers and additives at 60-160℃ for 0.5-6 minutes until the mixture is homogeneous, thus obtaining a fluororubber composition.

[0034] According to an embodiment of the second aspect of this application, a novel vulcanization system fluororubber composition is provided, which is obtained using the preparation method described in any of the above embodiments.

[0035] To facilitate a further understanding of this application, the solutions described below are further described in conjunction with embodiments. Those skilled in the art will understand that the embodiments described in this application are only some examples, and any other suitable specific embodiments are within the scope of this application.

[0036] Example 1 This embodiment provides a novel fluororubber composition with a vulcanization system. The preparation method and specific steps are as follows: 30L of deoxygenated deionized water is added to a 50L reactor. The air in the reactor is replaced with TFE to ensure that the oxygen content is ≤10ppm and the nitrogen concentration is ≤1.0%. The reactor is heated to 90℃, and a diaphragm compressor is used to add a mixture of monomers (tetrafluoroethylene: vinylidene fluoride: perfluoromethyl vinyl ether = 45:25:30mol%) to the reactor. After the pressure reaches 2.2MPa, stirring is started at 600rpm.

[0037] 4.5 kg of ammonium perfluorooctanoate, 2.7 kg of deionized water, and 2.0 kg of sulfurized monomer (CF2=CF(CF2)4COONa) were added to the reactor, along with 15 g of initiator (20 wt%, ammonium persulfate) to initiate the reaction. During the reaction, a mixed monomer (tetrafluoroethylene: vinylidene fluoride: perfluoromethyl vinyl ether = 45:25:30 mol%) was continuously introduced to maintain the reactor pressure at 2.2 MPa and the temperature at 90 °C until the predetermined feed amount was reached.

[0038] After the reaction is complete, the emulsion is collected, and raw rubber is obtained by coagulation, washing, drying and plasticizing. 100g of raw rubber is mixed with 20g of carbon black N990 and 3.0g of diethylene glycol dimethyl ether at 120℃ for 5min. After uniform mixing, a fluororubber composition is obtained.

[0039] Example 2 This embodiment provides a novel vulcanization system fluororubber composition, the preparation method and specific steps of which are as follows: This application differs from Example 1 in the following ways: The mixed monomers (tetrafluoroethylene: vinylidene fluoride: perfluoromethyl vinyl ether = 30:25:45 mol%) are added to the reaction vessel using a diaphragm compressor to reach a pressure of 2.2 MPa, and then the stirring is started at a speed of 600 rpm.

[0040] Example 3 This embodiment provides a novel vulcanization system of fluororubber composition, the preparation method and specific steps of which are as follows: This application differs from Example 1 in the following ways: The mixed monomers (tetrafluoroethylene: vinylidene fluoride: perfluoromethyl vinyl ether = 45:35:20 mol%) are added to the reaction vessel using a diaphragm compressor to make the pressure reach 2.2 MPa, and then the stirring is started at 600 rpm.

[0041] Example 4 This embodiment provides a novel vulcanization system for fluororubber composition, the preparation method and specific steps of which are as follows: This application differs from Example 1 in the following ways: After the reaction is completed, the emulsion is collected, and raw rubber is obtained by coagulation, washing, drying and plasticizing. 100g of raw rubber is mixed with 30g of carbon black N990 and 1.0g of diethylene glycol dimethyl ether at 120°C for 5min. After uniform mixing, the fluororubber composition is obtained.

[0042] Comparative Example 1 This comparative example provides a novel vulcanization system for fluororubber compositions, the preparation method and specific steps of which are as follows: 30L of deoxygenated deionized water is added to a 50L reactor, and the air in the reactor is replaced with TFE to ensure that the oxygen content in the reactor is ≤10ppm and the nitrogen concentration is ≤1.0%. The reactor is heated to 90℃, and a diaphragm compressor is used to add a mixture of monomers (tetrafluoroethylene: vinylidene fluoride: perfluoromethyl vinyl ether = 45:25:30mol%) to the reactor. After the pressure reaches 2.2MPa, stirring is started at 600rpm.

[0043] 4.5 kg of ammonium perfluorooctanoate, 2.7 kg of deionized water, and 2.0 kg of sulfurized monomer (CF2=CF(CF2)4COONa) were added to the reactor, along with 15 g of initiator (20 wt%, ammonium persulfate) to initiate the reaction. During the reaction, a mixed monomer (tetrafluoroethylene: vinylidene fluoride: perfluoromethyl vinyl ether = 45:25:30 mol%) was continuously introduced to maintain the reactor pressure at 2.2 MPa and the temperature at 90 °C until the predetermined feed amount was reached.

[0044] After the reaction is complete, the emulsion is collected, and raw rubber is obtained by coagulation, washing, drying and plasticizing. 100g of raw rubber and 20g of carbon black N990 are mixed at 120℃ for 5min. After uniform mixing, a fluororubber composition is obtained.

[0045] Comparative Example 2 This comparative example provides a novel vulcanization system of fluororubber composition, the preparation method and specific steps of which are as follows: This application differs from Example 1 in the following ways: The mixed monomers (tetrafluoroethylene: vinylidene fluoride: perfluoromethyl vinyl ether = 40:45:15mol%) are added to the reaction vessel using a diaphragm compressor to reach a pressure of 2.2MPa, and then the stirring is started at a speed of 600rpm.

[0046] Experimental Example The tensile strength, elongation, Shore A hardness, and permanent compression set of the fluororubber compositions in each embodiment and comparative example were tested, and the results are shown in Table 1. The testing methods are as follows: The tensile strength of the fluororubber composition was tested according to the Chinese national standard GB / T 528 on a universal testing machine, with a tensile strength TS=F.m / (W×t); where TS, MPa; F m t is the maximum force the specimen can withstand before fracture, in N; W is the width of the narrow section of the specimen, in m; t is the average thickness of the narrow section of the specimen, in m.

[0047] The elongation of the fluororubber composition was tested according to the Chinese national standard GB / T 528 on a universal testing machine. The elongation E was measured. b =(L b -L0) / L0; where E b ,%; L b L is the gauge length at which the specimen breaks, in mm; L0 is the original gauge length of the specimen, in mm.

[0048] The fluororubber composition was tested for Shore A hardness using a Shore A hardness tester according to ASTM D2240 standard.

[0049] The permanent compression set of fluororubber compositions was tested using a compression jig, a constant-temperature oven, and a thickness gauge, following the ASTM D395 standard. The initial thickness h0 was measured using a thickness gauge at the center point of the specimen. The specimen and restraint were placed in the compression jig and the screws were tightened. The restraint thickness was 75% of the initial thickness. The entire jig was placed in an oven at 200°C for 22 hours and 70 hours. After the specified time, the jig was quickly removed and allowed to cool at room temperature for 30 minutes. The jig was then released, the specimen removed, and allowed to rest horizontally on the test bench for 30 minutes. The final thickness h was then measured. f Permanent compressive deformation (C,%) = (h0 - h) f ) / (h0-h s ) × 100%; where h0 is the original thickness; h f The final thickness after restoration; h s The thickness is under compression.

[0050] Table 1. Test performance results of fluororubber compositions in each example and comparative example.

[0051] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0052] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A method for producing a novel vulcanization system fluororubber composition, characterized by, Includes the following steps: A fluororubber latex is obtained by passing comonomers into a vulcanization system for polymerization; wherein the comonomers include tetrafluoroethylene, vinylidene fluoride, and perfluoroalkyl vinyl ethers; and the vulcanization system includes deoxygenated deionized water, emulsifier, initiator, and vulcanization point monomer. The fluororubber emulsion is coagulated, washed, dried, and plasticized to obtain raw fluororubber. The fluororubber raw material, filler, and additives are mixed to obtain a fluororubber composition.

2. The preparation method according to claim 1, characterized in that, The perfluoroalkyl vinyl ether is selected from at least one of perfluoromethyl vinyl ether, perfluoroethyl vinyl ether, and perfluoropropyl vinyl ether; And / or, based on the comonomer, the perfluoroalkyl vinyl ether comprises 20-45% by weight.

3. The preparation method according to claim 2, characterized in that, The emulsifier is selected from at least one of perfluorocarboxylate, perfluoroether carboxylate, and perfluorosulfonate; And / or, based on the comonomer, the amount of the emulsifier is 0.01-5% by mass percentage.

4. The preparation method according to claim 3, characterized in that, The initiator is selected from at least one of potassium persulfate, sodium persulfate, and ammonium persulfate; And / or, based on the comonomer, the amount of the initiator is 0.01-5% by mass percentage.

5. The preparation method according to claim 4, characterized in that, The general formula for the sulfurization point monomer is CX1X2=CX3X4-Y-COOM; Wherein X1-X4 are H or F; Y is selected from one or more of alkyl, perfluoroalkyl, or partially fluoroalkyl, alkoxy, and polyether; wherein M is selected from at least one of Na, K, Ca, Mg, and NH4. And / or, by mass percentage, the amount of the vulcanization point monomer based on the comonomer is 0.01-5%.

6. The preparation method according to any one of claims 1-5, characterized in that, The polymerization reaction is carried out at a pressure of 1.4-4.0 MPa, a temperature of 60-100℃, a polymerization time of 2-12 h, and a stirring speed of 200-1000 rpm.

7. The preparation method according to claim 6, characterized in that, The filler is selected from at least one of carbon black, silica, calcium carbonate, and talc. And / or, based on the raw fluororubber, the amount of filler is 10-30% by mass percentage.

8. The preparation method according to claim 6, characterized in that, The auxiliary agent is at least one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol methyl ethyl ether; And / or, based on the raw fluororubber, the amount of the additive is 0.5-10% by mass percentage.

9. The preparation method according to claim 6, characterized in that, The mixing temperature is 60-160℃, and the mixing time is 0.5-6min.

10. A novel fluororubber composition with a vulcanization system, characterized in that, It is obtained using any of the preparation methods in claims 1-9.

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