Fluorosilicone rubber 2, 5-dimethyl-2, 5-bis (tert-butylperoxy) hexane

Abstract

The invention relates to a fluorosilicone rubber bis (2, 5-dimethyl-2, 5-bis-(tert-butylperoxy) hexane and a preparation method and application thereof, 2, 5-dimethyl-2, 5-bis-(tert-butylperoxy) hexane takes hydrophobic white carbon black as an absorption medium, and then is combined with polymethylvinylsiloxane with high vinyl content to improve the compatibility with fluorosilicone rubber, so that the fluorosilicone rubber bis (2, 5-dimethyl-2, 5-bis-(tert-butylperoxy) hexane is prepared. The performance of the fluorosilicone rubber is maintained; and the operation difficulty and the safety risk of a vulcanizing link of the fluorosilicone rubber are remarkably reduced. The raw materials in the production formula are easy to obtain, the production process is simple, the product quality is easy to control, the prepared vulcanizing agent product is applied to the fluorosilicone rubber industry, the labor efficiency is remarkably improved, the effect of improving the oil resistance of a vulcanized product is remarkable, and the fluorosilicone rubber product has a very good application prospect in the fluorosilicone rubber product industry.

Description

Technical Field

[0001] The invention relates to a fluorosilicone rubber dipentadienyl vulcanizing agent, a preparation method and application thereof, and the technical field of fluorosilicone rubber product industry application. Background Art

[0002] Fluorosilicone rubber products at home and abroad mainly use peroxide vulcanization system in the vulcanization process of compound rubber. Most of the commercially available vulcanizers are developed based on the vulcanization process of silicone rubber. Taking methyl vinyl silicone rubber as an example, silicone rubber vulcanization refers to the process of chemically grafting the vinyl active components in the compound rubber under heating, radiation and other conditions, so that the linear macromolecules are cross-linked into three-dimensional network macromolecules. The compound rubber undergoes a series of complex chemical reactions, changing from a plastic compound colloid state to a highly elastic cross-linked rubber state, thereby obtaining better mechanical and chemical properties. Silicone rubber uses a peroxide vulcanization system to complete this process. The peroxide vulcanization system uses peroxide as an initiator, and releases highly active free radicals through high-temperature homolysis. Alkoxy free radicals capture hydrogen atoms from the polymer chain to achieve the transfer of free radicals to the polymer main chain, and the two free radicals of adjacent polymer chains are coupled to complete the crosslinking.

[0003] At present, the di-250 vulcanizing agents used by fluorosilicone rubber product manufacturers are mainly liquid 2,5-dimethyl-2,5-bis-(tert-butylperoxide)hexane and C-20H vulcanizing agents suitable for silicone rubber vulcanization. Liquid di-250 vulcanizing agents have excellent solvent resistance of fluorosilicone rubber, which makes the vulcanization operation on the mixing mill extremely difficult, resulting in high labor intensity and extremely low efficiency. In addition, liquid di-250 has a great fire hazard during the vulcanization operation due to its volatility and flammability, which greatly limits its application in the product industry. In addition, CN101538406A discloses a formula of a silicone rubber anti-yellowing vulcanizer and a preparation method thereof, which adopts methyl vinyl raw rubber, white carbon black, and methyl silicone oil to change the vulcanizer from liquid to solid, thereby facilitating the processing of raw materials, increasing the safety of employee operations, ensuring the stability of the amount of vulcanizer added, and ensuring the quality of the product; high-hydrogen silicone oil and vinyl triethoxy silane are added to ensure the vulcanization speed when the silicone rubber raw materials are produced into products; because of the addition of high-hydrogen silicone oil, the anti-yellowing effect of the vulcanizer is greatly enhanced, the appearance of the silicone rubber is more transparent, and the beauty of the product is increased; because of the addition of vinyl triethoxy silane, the vulcanization speed is accelerated, the use of double two five is reduced, and the cost of raw materials is reduced.

[0004] On the other hand, manufacturers use silicone rubber vulcanizers for the vulcanization of fluorosilicone rubber, but the properties of fluorosilicone rubber are different from those of silicone rubber, resulting in poor compatibility between the two. As the amount of silicone added in the solid vulcanizer increases, the fluorosilicone compound and silicone rubber will become incompatible, affecting the degree of vulcanization and cross-linking density, causing the physical properties and chemical solvent resistance of fluorosilicone rubber products to deteriorate dramatically.

[0005] Therefore, there is an urgent need to develop a vulcanizing agent suitable for fluorosilicone rubber while overcoming the various defects of using silicone rubber vulcanizing agent and liquid dipentadienyl vulcanizing agent. Summary of the invention

[0006] In view of the above-mentioned prior art conditions, the purpose of the present invention is to provide a fluorosilicone rubber dipentadienyl vulcanizing agent and its preparation method and application. The present invention combines 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane with hydrophobic silica and high vinyl content polymethylvinylsiloxane to obtain a finished product, which has a short manufacturing process, simple operation, and can be mass-produced. In addition, the fluorosilicone rubber dipentadienyl vulcanizing agent of the present invention can effectively reduce the user's operating hours, reduce the risk of fire during the vulcanization operation, and maintain the various properties of fluorosilicone rubber products unchanged.

[0007] The technical solution for achieving the above-mentioned invention object can be summarized as follows:

[0008] Fluorosilicone rubber dipentadienyl vulcanizing agent includes the following raw materials:

[0009] Hydrophobic silica, 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane, high vinyl content polymethylvinylsiloxane;

[0010] The amount of 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane used is 300%-500% of the mass of hydrophobic silica, and the amount of high vinyl content polymethylvinylsiloxane used is 40%-70% of the total mass of hydrophobic silica and 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane.

[0011] According to the present invention, preferably, the hydrophobic silica is a product obtained by treating fumed silica with a hydrophobic treatment agent, and the hydrophobic treatment agent is at least one of fluorine-containing silazane, methyl silazane, vinyl silazane, and a silane coupling agent;

[0012] Preferably, the amount of the hydrophobic treatment agent used is 1%-3% of the mass of the fumed silica, and more preferably 1.5%-2.5%.

[0013] According to the present invention, preferably, the molar vinyl content of the high vinyl content polymethylvinylsiloxane is 1%-20%, more preferably 5%-15%.

[0014] According to the present invention, preferably, the average molecular weight of the high vinyl content polymethylvinylsiloxane is in the range of 600,000 to 1.3 million, preferably 700,000 to 900,000.

[0015] According to the present invention, the preparation method of the above-mentioned fluorosilicone rubber dipentadienyl vulcanizing agent comprises the following steps:

[0016] (1) adding fumed silica to a hydrophobic treatment agent, heating the mixture to 110° C. to 130° C. in a closed environment for reaction, and releasing the pressure and cooling the mixture to room temperature after the reaction is completed to obtain hydrophobic silica;

[0017] (2) adding the hydrophobic silica obtained in step (1) to 2,5-dimethyl-2,5-bis-(tert-butyl peroxide) hexane liquid, stirring and mixing to react, and controlling the reaction temperature to be ≤50° C. to obtain a reaction mass;

[0018] (3) Add the block obtained in step (2) to polymethylvinylsiloxane with high vinyl content, stir and mix to react, and control the reaction temperature to be ≤50° C. After the reaction is completed, a fluorosilicone rubber dipentadienyl vulcanizing agent is obtained.

[0019] According to the present invention, preferably, in step (1), the reaction temperature is 115° C.-125° C., and the reaction time is 2-6 hours.

[0020] According to the present invention, preferably, the stirring and mixing reaction time in step (2) is 1-3 hours, and the stirring and mixing reaction time in step (3) is 2-6 hours;

[0021] Preferably, the reaction temperature is controlled in steps (2) and (3) by passing cooling water.

[0022] According to the present invention, the above-mentioned fluorosilicone rubber dipentadienyl vulcanizing agent is used as a vulcanizing agent in fluorosilicone rubber and fluorosilicone rubber products.

[0023] The beneficial effects of the present invention are as follows:

[0024] 1. The fluorosilicone rubber dipentadienyl vulcanizing agent of the present invention is in a solid state, which can not only effectively reduce the user's operating hours, but also reduce the fire risk in the vulcanization operation, making the vulcanization process simple and safe.

[0025] 2. The fluorosilicone rubber di-pentyl vulcanizing agent of the present invention has good compatibility with fluorosilicone rubber, and the feeding can be completed by adding it once, which greatly shortens the feeding time and helps to reduce energy consumption and labor intensity.

[0026] 3. The fluorosilicone rubber dipentadienyl vulcanizing agent of the present invention has a short manufacturing process, simple operation, and is easy to mass produce.

[0027] 4. The fluorosilicone rubber dipentadienyl vulcanizing agent of the present invention maintains the chemical reagent resistance of the fluorosilicone rubber product without reducing it. DETAILED DESCRIPTION

[0028] The invention combines 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane with hydrophobic white carbon black and high-vinyl content polymethylvinylsiloxane to prepare a finished product.

[0029] The fluorosilicone rubber di-pentane vulcanizing agent of the present invention comprises the following raw materials:

[0030] Hydrophobic silica, 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane, high vinyl content polymethylvinylsiloxane;

[0031] The amount of 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane used is 300%-500% of the mass of hydrophobic white carbon black, and the amount of polymethylvinylsiloxane used is 40%-70% of the total mass of hydrophobic white carbon black and 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane.

[0032] According to the present invention, the purpose of hydrophobic silica is to effectively reduce the agglomeration of vulcanizing agent powder and improve the dispersion and uniformity of the vulcanizing agent. Hydrophilic silica has a large number of surface hydroxyl groups, which are easily adsorbed into agglomerates and difficult to disperse. In addition, it has a repulsive and difficult to dissolve in the liquid vulcanizing agent 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane due to the difference between the organic and inorganic phases. Hydrophobic silica is treated with reagents to remove a large number of free hydroxyl groups in silica to reduce agglomeration, and at the same time, organic groups are grafted onto silica to increase the compatibility with liquid 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane, effectively improving the uniformity of vulcanizing agent dispersion.

[0033] In one or more preferred embodiments, the amount of 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane used is 26%-400% of the mass of the hydrophobic white carbon black. After the materials are mixed and reacted, a transparent or translucent solid block can be obtained.

[0034] In one or more preferred embodiments, the hydrophobic silica is a product obtained by treating fumed silica with a hydrophobic treatment agent, and the hydrophobic treatment agent is at least one of fluorinated silazane, methyl silazane, vinyl silazane, and a silane coupling agent; preferably, the amount of the hydrophobic treatment agent is 1%-3% of the mass of the fumed silica, and more preferably 1.5%-2.5%.

[0035] When the added mass ratio of the hydrophobic treatment agent is less than 1%, the surface hydroxyl groups of the obtained hydrophobic silica are not treated cleanly, and it is easy to absorb water, causing defects such as bubbles to be generated during the vulcanization of the vulcanizing agent product; when the added mass ratio of the hydrophobic treatment agent is greater than 3%, the surface hydroxyl groups of the obtained hydrophobic silica are excessively treated and the unreacted reagents are difficult to pull out, making the product easy to react with the vinyl group in the fluorosilicone rubber during vulcanization, causing defects in the vulcanization system.

[0036] According to the present invention, the purpose of adding high vinyl content polymethylvinylsiloxane is to adjust the vulcanization crosslinking density of methylvinylsilicone and fluorosilicone rubber to ensure that the physical properties of fluorosilicone rubber, especially the chemical resistance, are not reduced.

[0037] In one or more preferred embodiments, the molar vinyl content of the high vinyl content polymethylvinylsiloxane is 1%-20%, more preferably 3%-15%.

[0038] If the vinyl molar content is too low, the added methyl vinyl siloxane molecular chain will form fewer cross-linking points with the main chain of the fluorosilicone rubber molecule during vulcanization. The three-dimensional structure formed is not enough to resist the destructive effect of chemical reagents on the main chain of the silicone molecule, causing the main chain of the silicone molecule to break, resulting in a significant decrease in the chemical reagent resistance of the fluorosilicone rubber products.

[0039] Too high a vinyl molar content will cause the added methyl vinyl siloxane molecular chain to form too many cross-linking points with the main chain of the fluorosilicone rubber molecule during vulcanization. The three-dimensional structure formed by too many cross-linking points can improve the chemical resistance of fluorosilicone rubber. However, due to over-vulcanization, the tensile strength, elongation and other indicators of fluorosilicone rubber products are significantly reduced and do not meet the use requirements.

[0040] In one or more preferred embodiments, the average molecular weight of polymethylvinylsiloxane is in the range of 600,000 to 900,000.

[0041] According to the present invention, the preparation method of fluorosilicone rubber dipentadienyl vulcanizing agent comprises the following steps:

[0042] (1) adding fumed silica to a hydrophobic treatment agent, heating the mixture to 110° C. to 130° C. in a closed environment for reaction, and releasing the pressure and cooling the mixture to room temperature after the reaction is completed to obtain hydrophobic silica;

[0043] (2) adding the hydrophobic silica obtained in step (1) to 2,5-dimethyl-2,5-bis-(tert-butyl peroxide) hexane liquid, stirring and mixing to react, and controlling the reaction temperature to be ≤50° C. to obtain a reaction mass;

[0044] (3) Add the material block obtained in step (2) to polymethylvinylsiloxane, stir and mix to react, and control the reaction temperature to be ≤50° C. After the reaction is completed, a fluorosilicone rubber dipentadienyl vulcanizing agent is obtained.

[0045] In one or more preferred embodiments, the reaction temperature in step (1) is 115° C.-125° C., and the reaction time is 2-6 hours. In this step, the fumed silica is subjected to a hydrophobic treatment.

[0046] In one or more preferred embodiments, the stirring and mixing reaction time in step (2) is 1-3 hours, and the stirring and mixing reaction time in step (3) is 2-6 hours;

[0047] Preferably, the reaction temperature is controlled in steps (2) and (3) by passing cooling water.

[0048] According to the present invention, the reaction temperature needs to be controlled to be ≤50°C during the stirring and mixing process in step (2). The flash point of 2,5-dimethyl-2,5-bis-(tert-butyl peroxide) hexane is 85-88°C. Controlling the reaction temperature to be ≤50°C is beneficial to inhibiting the volatilization of 2,5-dimethyl-2,5-bis-(tert-butyl peroxide) hexane and improving the uniformity of the vulcanizing agent.

[0049] The stirring and mixing reaction in step (3) needs to control the reaction temperature to be ≤50°C. If the reaction temperature is higher than 50°C, the 2,5-dimethyl-2,5-bis-(tert-butylperoxide)hexane in the vulcanizing agent will slowly induce vinyl crosslinking of the high vinyl content polymethylvinylsiloxane, causing the performance of the vulcanizing agent to fail and become unusable. When the reaction temperature is less than 50°C, this initiation effect is very slight and can be ignored.

[0050] According to the present invention, a method for preparing a fluorosilicone rubber dipentadienyl vulcanizing agent, a preferred embodiment, comprises the following steps:

[0051] (1) Put fumed silica A380\A300\A200 into a closed reaction stirring kettle, add one or more of fluorinated silazane, methyl silazane, vinyl silazane, silane coupling agent, etc. in an amount of 1%-13% by mass, slowly heat to 120° C. and maintain for 4 hours to react, and after the reaction is completed, release the pressure, seal and cool to room temperature;

[0052] (2) slowly adding 2,5-dimethyl-2,5-bis-(tert-butyl peroxide) hexane liquid to the treated hydrophobic white carbon black obtained in step (1) at a weight ratio of 1:2-1:5, turning on the stirring to slowly mix for 2 hours, and passing cooling water through the equipment to control the temperature not exceeding 50° C., and forming a uniform transparent or translucent block when the mixing is completed;

[0053] (3) Add polymethylvinylsiloxane with a high vinyl content of 1%-20% in a weight ratio of 1:1-1:3 to the transparent or translucent block obtained in step (2), start stirring and slowly mix for 4 hours, and pass cooling water through the equipment to control the temperature not exceeding 50° C. When the mixing is completed, a uniform transparent or translucent block is formed, which is the dipentadienyl vulcanizing agent for fluorosilicone rubber.

[0054] According to the present invention, the fluorosilicone rubber di-pentane vulcanizing agent is used as a vulcanizing machine in fluorosilicone rubber and fluorosilicone rubber products.

[0055] The present invention is further described in detail below in conjunction with specific examples. In the following examples, all the raw materials used are commercially purchased commodities, and the fluorosilicone rubber used for testing is commercially available NFS9470U.

[0056] Example 1

[0057] A method for preparing a di-pentadienyl vulcanizing agent for fluorosilicone rubber comprises the following steps:

[0058] (1) Put the fumed silica A380 into a closed reaction stirring kettle, add the hydrophobic treatment agent fluorinated silazane in an amount of 2% by mass, slowly raise the temperature to 120° C. and maintain the reaction for 4 hours. After the reaction is completed, release the pressure, seal and cool to room temperature.

[0059] (2) The treated hydrophobic silica obtained in step (1) is slowly added with 2,5-dimethyl-2,5-bis-(tert-butylperoxide)hexane liquid in a weight ratio of 1:2, and stirring is started to slowly mix for 2 hours. The entire equipment is cooled with water to control the temperature not to exceed 50° C., and a uniform transparent or translucent mass is formed when mixing is completed.

[0060] (3) adding polymethylvinylsiloxane having a high vinyl molar content of 5% and an average molecular weight of 1 million in a weight ratio of 1:1.5 to the transparent or translucent block obtained in step (2), starting stirring to perform slow mixing for 4 hours, passing cooling water through the equipment to control the temperature not exceeding 50° C., and forming a uniform transparent or translucent block when the mixing is completed.

[0061] The fluorosilicone rubber dipentadienyl vulcanizing agent product prepared in this embodiment was applied to the vulcanization process of commercially available NFS9470U, and vulcanization tests were performed using silicone rubber vulcanizing agent C-20H and 2,5-dimethyl-2,5-bis-(tert-butylperoxide)hexane for comparison.

[0062] The vulcanization conditions are:

[0063] The amount of the vulcanizing agent added is 0.50 g / 100 g of 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane, and other vulcanizing agents are added according to the concentration conversion.

[0064] Vulcanization temperature conditions: using molded flat plate

[0065] The first stage is 170℃*15min, and the second stage of vulcanization pressure is 200℃*4 hours.

[0066] The test was conducted in accordance with relevant national standards such as GB / T528-1998 Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber and GB / T1690-2006 Test method for liquid resistance of vulcanized rubber or thermoplastic rubber. The results are shown in Table 1.

[0067] Table 1—NFS9470U fuel oil resistance post-C performance test data

[0068]

[0069] From the experimental results in Table 1 above, it can be seen that the curing effect of the curing agent of the present invention is similar to that of liquid 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane, and the fuel oil resistance performance of C is better than that of silicone curing agent-C20H.

[0070] Example 2

[0071] A fluorosilicone rubber dipentadienyl vulcanizing agent was prepared according to the method of Example 1, and a vulcanization test was carried out together with liquid 2,5-dimethyl-2,5-bis-(tert-butylperoxide)hexane and a silicone rubber C-20H vulcanizing agent.

[0072] 10 kg of NFS9470U product was used for sulfur addition on an open mixing mill, and the operating hours were recorded. The test results are shown in Table 2.

[0073] Table 2

[0074]

[0075] According to the data results in Table 2, the vulcanizing operation time of the vulcanizing agent of the present invention is greatly shortened, which is beneficial to reducing energy consumption and labor intensity.

[0076] Example 3

[0077] A fluorosilicone rubber dipentadienyl vulcanizing agent was prepared according to the method of Example 1, except that the vinyl molar content of polymethylvinylsiloxane was changed from 5% to 3%. After the vulcanizing agent was prepared, a vulcanization test was performed using NFS9470U. The test data are shown in Table 3.

[0078] Table 3

[0079]

[0080]

[0081] According to the data results in Table 3, the vulcanizing agents obtained from the polymethylvinylsiloxanes with different vinyl contents of the present invention all meet the technical requirements of the standards.

[0082] Example 4

[0083] The fluorosilicone rubber dipentadienyl vulcanizing agent was prepared according to the method of Example 1, except that:

[0084] In step (1), the hydrophobic treatment agent is methylsilazane, and the amount of the hydrophobic treatment agent is 3% of the mass of the fumed silica. The amounts of the hydrophobic treatment agent are 4% and 6% of the mass of the fumed silica as comparative examples 1 and 2 for comparison. The comparative data are shown in Table 4 below.

[0085] Table 4

[0086]

[0087]

[0088] According to the data results in Table 4, the vulcanizing agent obtained by treating hydrophobic silica with different contents of the treating agent of the present invention has a great influence on the physical properties of fluorosilicone rubber products. When the amount of the hydrophobic treating agent exceeds 3% of the mass of the fumed silica, the physical properties of the obtained fluorosilicone rubber products will decrease.

[0089] Embodiment 5-7

[0090] The fluorosilicone rubber dipentadienyl vulcanizing agent was prepared according to the method of Example 1, except that:

[0091] In step (2), the hydrophobic white carbon black is added in a weight ratio of 1:3, 1:4, and 1:5, and 2,5-dimethyl-2,5-bis-(tert-butyl peroxide) hexane liquid is slowly added, and the same mass of high vinyl content polymethylvinylsiloxane is added to carry out step (3). The hydrophobic white carbon black in step (2) is added in a weight ratio of 1:1 and 1:2, and 2,5-dimethyl-2,5-bis-(tert-butyl peroxide) hexane liquid is added as comparative examples 3 and 4 for comparison. The comparative data of vulcanization under the same conditions are shown in Table 5 below.

[0092] Table 5

[0093]

[0094] According to the test data of the appearance machine in Table 5, the appearance of the vulcanizing agent obtained by treating the hydrophobic silica and liquid bis(2,5-dimethyl)hexane in different proportions and the vulcanization effect on the fluorosilicone rubber products are quite different, and the performance of the fluorosilicone rubber products is greatly affected. When the mass of the added 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane liquid to the mass of the hydrophobic silica is less than 3:1, the physical properties of the obtained fluorosilicone rubber products will decrease.

Claims

1. Fluorosilicone rubber dipentadienyl vulcanizing agent, characterized in that: The raw materials include: Hydrophobic silica, 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane, high vinyl content polymethylvinylsiloxane; The amount of 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane used is 300%-500% of the mass of hydrophobic silica, and the amount of high vinyl content polymethylvinylsiloxane used is 40%-70% of the total mass of hydrophobic silica and 2,5-dimethyl-2,5-bis-(tert-butylperoxy)hexane.

2. The fluorosilicone rubber dipentadienyl vulcanizing agent according to claim 1, characterized in that: The hydrophobic silica is a product obtained by treating fumed silica with a hydrophobic treatment agent, and the hydrophobic treatment agent is at least one of fluorine-containing silazane, methyl silazane, vinyl silazane, and a silane coupling agent.

3. The fluorosilicone rubber dipentadienyl vulcanizing agent according to claim 2, characterized in that: The dosage of the hydrophobic treatment agent is 1%-3% of the mass of the fumed silica.

4. The fluorosilicone rubber dipentadienyl vulcanizing agent according to claim 1, characterized in that: The molar vinyl content of the high vinyl content polymethylvinylsiloxane is 1%-20%.

5. The fluorosilicone rubber dipentadienyl vulcanizing agent according to claim 1, characterized in that: The average molecular weight of high vinyl content polymethylvinylsiloxane is in the range of 600,000 to 1.3 million.

6. A method for preparing the fluorosilicone rubber dipentadienyl vulcanizing agent according to any one of claims 1 to 5, comprising the following steps: (1) adding fumed silica to a hydrophobic treatment agent, heating the mixture to 110° C. to 130° C. in a closed environment for reaction, and releasing the pressure and cooling the mixture to room temperature after the reaction is completed to obtain hydrophobic silica; (2) adding the hydrophobic silica obtained in step (1) to 2,5-dimethyl-2,5-bis-(tert-butyl peroxide) hexane liquid, stirring and mixing to react, controlling the reaction temperature to ≤50° C., and obtaining a reaction mass; (3) Add the block obtained in step (2) to polymethylvinylsiloxane with high vinyl content, stir and mix to react, and control the reaction temperature to be ≤50° C. After the reaction is completed, a fluorosilicone rubber dipentadienyl vulcanizing agent is obtained.

7. The method for preparing the fluorosilicone rubber dipentadienyl vulcanizing agent according to claim 6, characterized in that: In step (1), the reaction temperature is 115° C.-125° C., and the reaction time is 2-6 hours.

8. The method for preparing the fluorosilicone rubber dipentadienyl vulcanizing agent according to claim 6, characterized in that: The stirring and mixing reaction time in step (2) is 1-3 hours, and the stirring and mixing reaction time in step (3) is 2-6 hours.

9. The method for preparing the fluorosilicone rubber dipentadienyl vulcanizing agent according to claim 6, characterized in that: The reaction temperature is controlled by passing cooling water in steps (2) and (3).

10. Use of the fluorosilicone rubber dipentadienyl vulcanizing agent according to any one of claims 1 to 5 as a vulcanizing agent in fluorosilicone rubber and fluorosilicone rubber products.

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