Phenyl vinyl silicone rubber composition and preparation method thereof

Abstract

The invention provides a phenyl vinyl silicone rubber composition and a preparation method thereof. The phenyl vinyl silicone rubber composition comprises the following components in parts by weight: 100 parts of phenyl vinyl silicone rubber, 20-50 parts of a reinforcing filler, 3-15 parts of a structural treating agent and 1-3 parts of a heat-resistant agent, wherein the content of phenyl in the phenyl vinyl silicone rubber is 8-15 mol%, and the content of vinyl in the phenyl vinyl silicone rubber is 0.04-0.25 mol%; the reinforcing filler comprises white carbon black; the structure treating agent is prepared from silazane, hydroxyl silicone oil, vinyl hydroxyl silicone oil, vinyl trimethoxy silane, zinc stearate and water according to the weight ratio of 1 to (0.2 to 0.8) to (0.05 to 0.2) to (0.005 to 0.02) to (0.01 to 0.02) to (0.005 to 0.02). The invention also provides silicone rubber formed by the phenyl vinyl silicone rubber composition and a vulcanizing agent. The phenyl vinyl silicone rubber composition disclosed by the invention has improved heat resistance, and the heat resistance grade of the silicone rubber can be improved to 300 DEG C from the common heat resistance temperature of 200 DEG C or 250 DEG C.

Description

Technical Field

[0001] The invention belongs to the technical field of silicone rubber, and in particular relates to a phenyl vinyl silicone rubber composition with improved heat resistance and a preparation method thereof. Background Art

[0002] Methyl vinyl silicone rubber (abbreviated as "VMQ") has excellent heat aging resistance and mechanical properties and is widely used. However, methyl vinyl silicone rubber can usually only be used at temperatures below 200°C, and its heat resistance needs to be further improved.

[0003] Chinese patent CN113956668B discloses ultra-high heat-resistant silicone rubber and its preparation method, which improves the heat resistance and the use temperature by modifying VMQ with a mixture of polysilazane and iron-doped titanium dioxide. However, its high cost and great processability problems seriously affect its practical application.

[0004] Chinese patent application CN117089208A discloses a high temperature resistant silicone rubber composition, which is prepared by surface-modifying nano inorganic heat resistant additives such as vinyl silane coupling agent, hydrogen siloxane ring body, methyl siloxane ring body and end-capping agent and then adding them to polysiloxane to improve heat resistance. However, its heat resistance effect is limited and it can only be used for a short period of time at 300°C.

[0005] Chinese patent application CN114058189A discloses an addition-type flame-retardant and high-temperature resistant silicone rubber and its preparation method and application, using vinyl-terminated polysiloxane with low hydroxyl content, low volatility and low ion content and hydrogen-containing polysiloxane with low volatility and low ion content, and heat-resistant agent pre-treated with silane coupling agent to achieve flame retardant and heat-resistant effects. The silicone rubber uses a platinum vulcanization system, and the process of treating heat-resistant agent and vulcanizing agent is complicated, the cost is high, and the temperature control requirements of the molding process are high, which is not conducive to large-scale production and amplification, and the tear strength and elongation of the rubber material decrease significantly after thermal aging.

[0006] Chinese patent application CN117165088A discloses a high resilience heat-resistant silicone rubber and a preparation method thereof, which improves its heat resistance by introducing diphenyldihydroxysilane and a heat-resistant agent into VMQ. However, it mainly studies the resilience, and the heat-resistant temperature is only 200°C.

[0007] Phenyl vinyl silicone rubber (abbreviated as "PVMQ") is a silicone rubber that introduces diphenylsiloxane chain segments (or methylphenylsiloxane chain segments) into the molecular chain of methyl vinyl silicone rubber. The introduction of phenyl groups into the molecular structure destroys the regularity of the siloxane molecular structure, reduces the crystallinity of the polymer, and improves cold resistance. Therefore, in addition to the small compression permanent deformation, wide operating temperature range, aging resistance, shock resistance, moisture resistance and excellent electrical insulation properties of methyl vinyl silicone rubber, phenyl silicone rubber also has excellent low temperature resistance, ablation resistance and radiation resistance.

[0008] According to the phenyl content, phenyl vinyl silicone rubber is divided into three types: low phenyl, medium phenyl and high phenyl.

[0009] (1) Low phenyl silicone rubber

[0010] When the phenyl content is 5-10 mol%, the hardening temperature of the rubber drops to -115°C, which makes it have unique cold resistance. It can still maintain its elasticity at -70 to -100°C and has the best low-temperature performance among all rubbers.

[0011] (2) Medium phenyl silicone rubber

[0012] The phenyl content is 15-25 mol%, and it has the characteristics of ablation resistance and flame resistance, and can self-extinguish once it catches fire.

[0013] (3) High phenyl silicone rubber

[0014] When the phenyl content is above 30 mol%, it has excellent radiation resistance and can withstand γ-rays of 2.58×10 4 c / kg, and can be used under radiation conditions and still maintain good mechanical properties.

[0015] The production and application of medium-phenyl and high-phenyl silicone rubbers are subject to certain restrictions due to their difficult processing and poor physical and mechanical properties.

[0016] In addition, some applications require rubber that can withstand higher temperatures while maintaining low-temperature performance, especially in aerospace, nuclear power and other occasions, where extreme environments require rubber materials that can adapt to a wider temperature range.

[0017] EP2915851B1 discloses a thermosetting addition reaction type silicone rubber composition and proposes a method for improving the heat resistance of phenyl silicone rubber. However, the heat resistance temperature is only 180°C and the temperature range is relatively narrow, which is not conducive to expanding the scope of use.

[0018] Chinese patent CN105814649B discloses an insulated wire, which believes that controlling the content of siloxane units with phenyl groups to more than 0.5 mol% can improve heat resistance, and at the same time, the content of silicon dioxide is less than 40 mol%, which makes the heat resistance excellent. Although the patent describes the retention of elongation after aging, it only does not do certain research and description on other aspects of performance.

[0019] Therefore, there is a need to provide silicone rubber with improved heat resistance. Summary of the invention

[0020] In view of this, the purpose of the present invention is to provide a phenyl vinyl silicone rubber composition with improved heat resistance and a preparation method thereof in view of the technical problems existing in the prior art. The phenyl vinyl silicone rubber composition of the present invention has improved heat resistance and can improve the heat resistance grade of silicone rubber from the general heat resistance temperature of 200° C. or 250° C. to 300° C. On the other hand, the present invention also provides silicone rubber formed by the phenyl vinyl silicone rubber composition and a vulcanizing agent.

[0021] The objectives of the present invention are achieved through the following technical solutions.

[0022] In a first aspect, the present invention provides a phenyl vinyl silicone rubber composition, wherein the phenyl vinyl silicone rubber composition comprises 100 parts by weight of phenyl vinyl silicone rubber, 20-50 parts by weight of reinforcing filler, 3-15 parts by weight of structural treatment agent and 1-3 parts by weight of heat resistant agent;

[0023] The phenyl content of the phenyl vinyl silicone rubber is 8-15 mol%, and the vinyl content is 0.04-0.25 mol%; the reinforcing filler includes white carbon black; the structural treatment agent includes silazane, hydroxy silicone oil, vinyl hydroxy silicone oil, vinyl trimethoxy silane, zinc stearate and water in a weight ratio of 1:(0.2-0.8):(0.05-0.2):(0.005-0.02):(0.01-0.02):(0.005-0.02).

[0024] The inventors of the present application have found that the silicone rubber prepared by using phenyl vinyl silicone rubber with a specific vinyl content as raw rubber, using white carbon black as a reinforcing filler, and using a structural treatment agent containing silazane can not only maintain the original low-temperature resistance of phenyl vinyl silicone rubber, but also improve the high-temperature resistance of the material, broaden the scope of use of the material, and help stimulate market vitality. Furthermore, the water in the structural treatment agent can promote the hydrolysis of silazane, and zinc stearate is a processing aid that can improve the subsequent processing performance of the rubber.

[0025] According to the phenyl vinyl silicone rubber composition provided by the present invention, the weight average molecular weight of the phenyl vinyl silicone rubber is 500000-700000. For example, the weight average molecular weight of the phenyl vinyl silicone rubber can be 500000, 510000, 520000, 530000, 540000, 550000, 560000, 570000, 580000, 5900001, 600000, 610000, 620000, 630000, 640000, 650000, 660000, 670000, 6800001, 690000, 700000 or a range thereof.

[0026] According to the phenyl vinyl silicone rubber composition provided by the present invention, the phenyl content in the phenyl vinyl silicone rubber can be 8 mol%, 9 mol%, 10 mol%, 11 mol%, 12 mol%, 13 mol%, 14 mol%, 15 mol% or a range thereof. In some embodiments, the phenyl content in the phenyl vinyl silicone rubber is 8-10 mol%.

[0027] According to the phenyl vinyl silicone rubber composition provided by the present invention, the vinyl content of the phenyl vinyl silicone rubber can be 0.04 mol%, 0.045 mol%, 0.05 mol%, 0.055 mol%, 0.06 mol%, 0.065 mol%, 0.07 mol%, 0.075 mol%, 0.08 mol%, 0.085 mol%, 0.09 mol%, 0.095 mol%, 0.1 mol%, 0.12 mol%, 0.15 mol%, 0.18 mol%, 0.20 mol%, 0.23 mol%, 0.25 mol% or a range thereof.

[0028] In some embodiments, the vinyl content of the phenyl vinyl silicone rubber is 0.04-0.12 mol%, preferably 0.04-0.08 mol%. Within the preferred vinyl content range, the phenyl vinyl silicone rubber composition of the present invention has further improved heat resistance.

[0029] In the present invention, a phenyl vinyl silicone rubber having a desired vinyl content and a desired phenyl content can be obtained by compounding. In some specific embodiments, the phenyl vinyl silicone rubber comprises a first phenyl vinyl silicone rubber and a second phenyl vinyl silicone rubber, wherein the vinyl content of the first phenyl vinyl silicone rubber is 0.04 mol%, the vinyl content of the second phenyl vinyl silicone rubber is 0.08 mol%, and the weight ratio of the first phenyl vinyl silicone rubber to the second phenyl vinyl silicone rubber is 0:100-100:0, preferably 10:90-90:10, more preferably 15:85-85:15, and further preferably 15:85-25:75.

[0030] According to the phenyl vinyl silicone rubber composition provided by the present invention, the specific surface area of ​​the white carbon black is 100-300m 2 For example, the specific surface area of ​​the white carbon black can be 100 m 2 / g, 110m 2 / g, 120m 2 / g, 150m 2 / g, 180m 2 / g, 200m 2 / g, 220m 2 / g, 250m 2 / g, 280m 2 / g、300m 2 / g or a range of its composition.

[0031] According to the phenyl vinyl silicone rubber composition provided by the present invention, the amount of the reinforcing filler can be 20 parts by weight, 21 parts by weight, 22 parts by weight, 23 parts by weight, 24 parts by weight, 25 parts by weight, 26 parts by weight, 27 parts by weight, 28 parts by weight, 29 parts by weight, 30 parts by weight, 32 parts by weight, 35 parts by weight, 38 parts by weight, 40 parts by weight, 42 parts by weight, 45 parts by weight, 48 parts by weight, 50 parts by weight or a range thereof. In some embodiments, the amount of the reinforcing filler is 25-45 parts by weight.

[0032] According to the phenyl vinyl silicone rubber composition provided by the present invention, the amount of the structural treatment agent can be 3 parts by weight, 4 parts by weight, 5 parts by weight, 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight, 10 parts by weight, 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight, 15 parts by weight or a range thereof. In some embodiments, the amount of the structural treatment agent is 5-10 parts by weight.

[0033] According to the phenyl vinyl silicone rubber composition provided by the present invention, the silazane is hexamethyldisilazane.

[0034] According to the phenyl vinyl silicone rubber composition provided by the present invention, the hydroxyl content of the hydroxy silicone oil is above 5wt%, preferably 5wt%-10wt%; the viscosity at 25°C is ≤30mm 2 / s, preferably 10-30mm 2 / s, more preferably 15-25mm 2 / s.

[0035] According to the phenyl vinyl silicone rubber composition provided by the present invention, examples of hydroxy silicone oil suitable for use in the present invention include but are not limited to: α,γ-dihydroxypolydimethylsilane.

[0036] According to the phenyl vinyl silicone rubber composition provided by the present invention, the weight ratio of the silazane to the hydroxy silicone oil can be 1:0.2, 1:0.25, 1:0.3, 1:0.35, 1:0.4, 1:0.45, 1:0.5, 1:0.55, 1:0.6, 1:0.65, 1:0.7, 1:0.75, 1:0.8 or a range thereof. In some embodiments, the weight ratio of the silazane to the hydroxy silicone oil is 1:(0.4-0.5).

[0037] According to the phenyl vinyl silicone rubber composition provided by the present invention, the hydroxyl content of the vinyl hydroxy silicone oil is 5-7wt%, for example, 6.0wt%; the vinyl content is 6-8mol%, for example, 7.0mol%; the viscosity at 25°C is 30-40mm 2 / s.

[0038] According to the phenyl vinyl silicone rubber composition provided by the present invention, the weight ratio of the silazane to the vinyl hydroxy silicone oil can be 1:0.05, 1:0.06, 1:0.07, 1:0.08, 1:0.09, 1:0.10, 1:0.11, 1:0.12, 1:0.13, 1:0.14, 1:0.15, 1:0.18, 1:0.20 or a range thereof. In some embodiments, the weight ratio of the silazane to the vinyl hydroxy silicone oil is 1:(0.08-0.15).

[0039] According to the phenyl vinyl silicone rubber composition provided by the present invention, the weight ratio of the silazane to the vinyl trimethoxy silane can be 1:0.005, 1:0.006, 1:0.007, 1:0.008, 1:0.009, 1:0.01, 1:0.011, 1:0.012, 1:0.013, 1:0.014, 1:0.015, 1:0.018, 1:0.02 or a range thereof. In some embodiments, the weight ratio of the silazane to the vinyl trimethoxy silane is 1:(0.008-0.015).

[0040] According to the phenyl vinyl silicone rubber composition provided by the present invention, the weight ratio of the silazane to the zinc stearate can be 1:0.01, 1:0.011, 1:0.012, 1:0.013, 1:0.014, 1:0.015, 1:0.016, 1:0.017, 1:0.018, 1:0.019, 1:0.02 or a range thereof.

[0041] According to the phenyl vinyl silicone rubber composition provided by the present invention, the weight ratio of the silazane to water can be 1:0.05, 1:0.06, 1:0.07, 1:0.08, 1:0.09, 1:0.10, 1:0.11, 1:0.12, 1:0.13, 1:0.14, 1:0.15, 1:0.18, 1:0.20 or a range thereof. In some embodiments, the weight ratio of the silazane to water is 1:(0.08-0.15).

[0042] According to the phenyl vinyl silicone rubber composition provided by the present invention, the heat-resistant agent is selected from cerium oxide, titanium dioxide and heat-resistant agent H0, preferably titanium dioxide. In the present invention, titanium dioxide is used as a heat-resistant agent and is used in combination with a structural treatment agent, which has further improved heat resistance.

[0043] In a second aspect, the present invention also provides a method for preparing a phenyl vinyl silicone rubber composition having improved heat resistance, wherein the preparation method comprises the following steps:

[0044] S1, adding phenyl vinyl silicone rubber, silazane, hydroxy silicone oil, vinyl hydroxy silicone oil and vinyl trimethoxy silane into a kneader for kneading to obtain a first mixed material;

[0045] S2, adding reinforcing filler, water and zinc stearate to the first mixed material, and kneading at a temperature of 140-160° C. to obtain a second mixed material;

[0046] S3. Add a heat-resistant agent to the second mixed material, and knead the mixture at 20-90° C. to obtain a phenyl vinyl silicone rubber composition.

[0047] According to the preparation method provided by the present invention, the kneading time in step S1 is 3-4 hours.

[0048] According to the preparation method provided by the present invention, the mixing time in step S2 is 1-3 hours.

[0049] According to the preparation method provided by the present invention, in step S3, the kneading temperature is 60-90° C., and the kneading time is 10-30 minutes.

[0050] In a third aspect, the present invention provides a silicone rubber formed from the phenyl vinyl silicone rubber composition and a vulcanizing agent.

[0051] According to the silicone rubber provided by the present invention, there is no special requirement on the type of vulcanizing agent, and any known vulcanizing agent in the art can be used, for example, the di-2-pentane vulcanizing agent purchased from Shenzhen Aviation Materials New Materials Co., Ltd.

[0052] According to the silicone rubber provided by the present invention, the weight ratio of the phenyl vinyl silicone rubber composition to the vulcanizing agent is 100:(0.1-5), preferably 100:(0.2-2), and more preferably 100:(0.5-1.5).

[0053] The present invention has the following advantages:

[0054] (1) In the present invention, phenyl vinyl silicone rubber is used as the main material of the heat-resistant rubber, which not only maintains the original low-temperature resistance of phenyl vinyl silicone rubber, but also improves the high-temperature resistance of the material, from the general heat-resistant temperature of 200°C or 250°C to 300°C, broadens the application scope of the material, and is conducive to stimulating market vitality. In particular, after aging at 300°C for 3 days, the silicone rubber of the present invention still has certain mechanical properties and other characteristics, and has good high-temperature resistance.

[0055] (2) The phenyl vinyl silicone rubber composition of the present invention is kneaded to form a solid mixture that is approximately milky white in color, has excellent processing performance, and has stable comprehensive physical properties. It is suitable for production by processes such as extrusion, molding, and coating. It not only retains traditional process characteristics and does not increase costs, but also broadens the temperature resistance range of silicone rubber, and can be used in a wide temperature range of -100°C to 300°C.

[0056] (3) The phenyl vinyl silicone rubber composition and / or silicone rubber of the present invention is processed into various low-pressure seals, sealing rings, sealing pads, films, hoses and rods through molding and extrusion, which can be used in occasions requiring low temperature resistance, ablation resistance, high energy radiation resistance, heat insulation, etc., and has a wide range of applications. For example, it can be used in the fields of construction, electronic appliances, automobiles, industrial deep refrigeration, aviation, aerospace, nuclear power, engines, etc. Specifically, in the construction industry, it is used to make waterproof materials, sound insulation materials, refractory materials, etc.; in the automobile industry, it is used to prepare various types of vehicle sealing rings, oil seals, diaphragms, catheters, valve linings, etc.; in the medical industry, it is used to make artificial organs, heart stents and other medical devices; in the petrochemical industry, it is used to prepare various types of high temperature, low temperature, chemical corrosion resistant pumps, valves, oil tanks and other equipment sealing products; in the aviation industry, it is used to prepare fuel oil and lubricating oil resistant seals and contact parts on aircraft, such as various O-rings, gaskets, sealing rings, sensor materials, diaphragms, and gaskets. DETAILED DESCRIPTION

[0057] The equipment and raw materials used in the examples and comparative examples of the present invention are as follows.

[0058] Equipment and instruments: kneading machine, mixing mill, tensile strength tester, hardness tester, specific gravity meter, high temperature aging box.

[0059] The raw materials are as follows:

[0060] 1. Phenyl vinyl silicone rubber

[0061] (1) Phenyl vinyl silicone rubber raw rubber I, purchased from Shandong Bito Silicone Co., Ltd., with a phenyl content of 8 mol%, a vinyl content of 0.02 mol%, and a weight average molecular weight of 600,000;

[0062] (2) Phenyl vinyl silicone rubber raw rubber II, purchased from Shandong Bito Silicone Co., Ltd., phenyl content 8 mol%, vinyl content 0.04 mol%, weight average molecular weight 600,000;

[0063] (3) Phenyl vinyl silicone rubber raw rubber III, purchased from Shandong Bito Silicone Co., Ltd., phenyl content 8 mol%, vinyl content 0.08 mol%, weight average molecular weight 580,000.

[0064] (4) Phenyl vinyl silicone rubber raw rubber IV, purchased from Shandong Bito Silicone Co., Ltd., phenyl content 8 mol%, vinyl content 0.12 mol%, weight average molecular weight 590,000.

[0065] 2. Fumed silica, M-5, surface area 200m 2 / g, selected from Jiangxi Cabot Co., Ltd.

[0066] 3.α,γ-dihydroxypolydimethylsilane, GT-14, viscosity at 25℃ is 25mm 2 / s, hydroxyl content is 8.5wt%, Xuancheng Guixin New Materials Co., Ltd.

[0067] 4. Hexamethyldisilazane, HMDZ, Bluestar Starfire Silicones Co., Ltd.

[0068] 5. Heat resistant agent

[0069] Heat resistant agent 19338, the main component is cerium oxide, Jiangxi Lanxing Xinghuo Silicone Co., Ltd.;

[0070] Heat resistant agent PF-2, the main component is TiO2, Evonik Chemical Co., Ltd.;

[0071] Heat Resistant H0, Wacker Chemie Co., Ltd.

[0072] 6.Bis(250-400) vulcanizing agent (paste, effective content 50%), Shenzhen Aviation Materials New Materials Co., Ltd.

[0073] The performance testing methods in the embodiments of the present invention are all conventional testing methods in the art, with special mention:

[0074] Viscosity is Mooney viscosity, based on the test standard GB / T 1232.1-2000;

[0075] The test standard for tear strength / type B is GB / T 529-2023;

[0076] The test standard for tear strength / type C is GB / T 529-2023.

[0077] Example 1

[0078] (1) 100 parts by weight of phenyl vinyl silicone rubber (including 40 parts by weight of phenyl vinyl silicone rubber II (Shandong Bito Silicone Co., Ltd.) with a weight average molecular weight of 600,000, a vinyl content of 0.04 mol%, and a phenyl content of 8 mol%, and 60 parts by weight of phenyl vinyl silicone rubber III (Shandong Bito Silicone Co., Ltd.) with a weight average molecular weight of 580,000, a vinyl content of 0.08 mol%, and a phenyl content of 8 mol%)), 3 parts by weight of hydroxy silicone oil GT-14 (viscosity of 25 mm at 25°C) were added. 2 / s, hydroxyl content of 8.5wt%), 6 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity of 35mm at 25°C) 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%), 0.05 weight parts of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0079] (2) adding 42 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, heating to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), and cooling the rubber material to below 100° C. to obtain a second mixed material;

[0080] (3) Add 1 part by weight of heat-resistant agent 19338 to the second mixed material, continue kneading (pass cooling water, the temperature is controlled at 90° C.) for 20 min, discharge the material, cool for more than 30 min, weigh and package to obtain a rubber compound;

[0081] (4) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizing agent. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizing agent in the rubber mix. After passing the mixture through a thin mill for six times, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 1.

[0082] Example 2

[0083] (1) 100 parts by weight of phenyl vinyl silicone rubber (including 20 parts by weight of phenyl vinyl silicone rubber II (Shandong Bito Silicone Co., Ltd.) with a weight average molecular weight of 600,000, a vinyl content of 0.04 mol%, and a phenyl content of 8 mol%, and 80 parts by weight of phenyl vinyl silicone rubber III (Shandong Bito Silicone Co., Ltd.) with a weight average molecular weight of 580,000, a vinyl content of 0.08 mol%, and a phenyl content of 8 mol%)), 3 parts by weight of hydroxy silicone oil GT-14 (viscosity of 25 mm at 25°C) were added. 2 / s, hydroxyl content of 8.5wt%), 6 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity of 35mm at 25°C) 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%) and 0.05 weight part of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0084] (2) adding 42 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, heating to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), and cooling the rubber material to below 100° C. to obtain a second mixed material;

[0085] (3) adding 1.3 parts by weight of heat-resistant agent PF-2 to the second mixed material, continuing to knead (passing cooling water, the temperature is controlled at 90° C.) for 20 min, discharging the material, cooling for more than 30 min, weighing and packaging to obtain a rubber compound;

[0086] (4) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizing agent. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizing agent in the rubber mix. After passing the mixture through a thin mill for six times, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 1.

[0087] Example 3

[0088] (1) 100 parts by weight of phenyl vinyl silicone rubber (phenyl vinyl silicone rubber III with a weight average molecular weight of 580,000, a vinyl content of 0.08 mol%, and a phenyl content of 8 mol%, Shandong Bituo Silicone Co., Ltd.), 3 parts by weight of hydroxy silicone oil GT-14 (viscosity of 25 mm at 25 ° C) were mixed with 2 / s, hydroxyl content of 8.5wt%), 6 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity of 35mm at 25°C) 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%) and 0.05 weight part of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0089] (2) adding 42 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, heating to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), and cooling the rubber material to below 100° C. to obtain a second mixed material;

[0090] (3) Add 2 parts by weight of heat-resistant agent H0 to the second mixed material, continue kneading (pass cooling water, the temperature is controlled at 90° C.) for 20 min, discharge the material, cool for more than 30 min, weigh and package to obtain a rubber compound;

[0091] (4) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizing agent. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizing agent in the rubber mix. After passing the mixture through a thin mill for six times, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 1.

[0092] Example 4

[0093] (1) 100 parts by weight of phenyl vinyl silicone rubber (weight average molecular weight 600,000, vinyl content 0.04 mol%, phenyl content 8 mol% phenyl vinyl silicone rubber II, Shandong Bito Silicone Co., Ltd.), 3 parts by weight of hydroxy silicone oil GT-14 (viscosity 25 mm 2 / s, hydroxyl content of 8.5wt%), 6 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity of 35mm at 25°C) 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%) and 0.05 weight part of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0094] (2) adding 42 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, heating to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), and cooling the rubber material to below 100° C. to obtain a second mixed material;

[0095] (3) Add 2 parts by weight of heat-resistant agent H0 to the second mixed material, continue kneading (pass cooling water, the temperature is controlled at 90° C.) for 20 min, discharge the material, cool for more than 30 min, weigh and package to obtain a rubber compound;

[0096] (4) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizing agent. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizing agent in the rubber mix. After passing the mixture through a thin mill for six times, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 1.

[0097] Example 5

[0098] (1) 100 parts by weight of phenyl vinyl silicone rubber raw rubber (phenyl vinyl silicone rubber IV with a weight average molecular weight of 590,000, a vinyl content of 0.12 mol%, and a phenyl content of 8 mol%, Shandong Bituo Silicone Co., Ltd.), 3 parts by weight of hydroxy silicone oil GT-14 (viscosity of 25 mm at 25 ° C) 2 / s, hydroxyl content of 8.5wt%), 6 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity of 35mm at 25°C) 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%) and 0.05 weight part of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0099] (2) adding 42 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, heating to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), and cooling the rubber material to below 100° C. to obtain a second mixed material;

[0100] (3) Add 2 parts by weight of heat-resistant agent H0 to the second mixed material, continue kneading (pass cooling water, the temperature is controlled at 90° C.) for 20 min, discharge the material, cool for more than 30 min, weigh and package to obtain a rubber compound;

[0101] (4) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizing agent. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizing agent in the rubber mix. After passing the mixture through a thin mill for six times, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 1.

[0102] Example 6

[0103] (1) 100 parts by weight of phenyl vinyl silicone rubber (including 40 parts by weight of phenyl vinyl silicone rubber II (Shandong Bito Silicone Co., Ltd.) with a weight average molecular weight of 600,000, a vinyl content of 0.04 mol%, and a phenyl content of 8 mol%, and 60 parts by weight of phenyl vinyl silicone rubber III (Shandong Bito Silicone Co., Ltd.) with a weight average molecular weight of 580,000, a vinyl content of 0.08 mol%, and a phenyl content of 8 mol%)), 1.83 parts by weight of hydroxy silicone oil GT-14 (viscosity of 25 mm at 25°C) 2 / s, hydroxyl content of 8.5wt%), 4 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity of 35mm at 25°C) 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%), 0.05 weight parts of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0104] (2) adding 25 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, heating to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), and cooling the rubber material to below 100° C. to obtain a second mixed material;

[0105] (3) Add 1 part by weight of heat-resistant agent 19338 to the second mixed material, continue kneading (pass cooling water, the temperature is controlled at 90° C.) for 20 min, discharge the material, cool for more than 30 min, weigh and package to obtain a rubber compound;

[0106] (4) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizing agent. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizing agent in the rubber mix. After passing the mixture through a thin mill for six times, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 2.

[0107] Example 7

[0108] (1) 100 parts by weight of phenyl vinyl silicone rubber (including 20 parts by weight of phenyl vinyl silicone rubber II (Shandong Bito Silicone Co., Ltd.) with a weight average molecular weight of 600,000, a vinyl content of 0.04 mol%, and a phenyl content of 8 mol%, and 80 parts by weight of phenyl vinyl silicone rubber III (Shandong Bito Silicone Co., Ltd.) with a weight average molecular weight of 580,000, a vinyl content of 0.08 mol%, and a phenyl content of 8 mol%), 1.83 parts by weight of hydroxy silicone oil GT-14 (viscosity at 25°C: 25 mm2 / s, hydroxyl content: 8.5 wt%), 4 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity at 25°C: 35 mm2 / s), and 1.83 parts by weight of hydroxy silicone oil GT-14 (viscosity at 25°C: 25 mm2 / s, hydroxyl content: 8.5 wt%). 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%) and 0.05 weight part of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0109] (2) adding 25 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, heating to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), and cooling the rubber material to below 100° C. to obtain a second mixed material;

[0110] (3) adding 1.3 parts by weight of heat-resistant agent PF-2 to the second mixed material, continuing to knead (passing cooling water, the temperature is controlled at 90° C.) for 20 min, discharging the material, cooling for more than 30 min, weighing and packaging to obtain a rubber compound;

[0111] (4) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizing agent. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizing agent in the rubber mix. After passing the mixture through a thin mill for six times, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 2.

[0112] Example 8

[0113] (1) 100 parts by weight of phenyl vinyl silicone rubber (phenyl vinyl silicone rubber III with a weight average molecular weight of 580,000, a vinyl content of 0.08 mol%, and a phenyl content of 8 mol%, Shandong Bituo Silicone Co., Ltd.), 1.83 parts by weight of hydroxy silicone oil GT-14 (viscosity of 25 mm at 25 ° C) 2 / s, hydroxyl content of 8.5wt%), 4 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity of 35mm at 25°C) 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%) and 0.05 weight part of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0114] (2) adding 25 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, heating to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), and cooling the rubber material to below 100° C. to obtain a second mixed material;

[0115] (3) Add 2 parts by weight of heat-resistant agent H0 to the second mixed material, continue kneading (pass cooling water, the temperature is controlled at 90° C.) for 20 min, discharge the material, cool for more than 30 min, weigh and package to obtain a rubber compound;

[0116] (4) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizing agent. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizing agent in the rubber mix. After passing the mixture through a thin mill for six times, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 2.

[0117] Example 9

[0118] (1) 100 parts by weight of phenyl vinyl silicone rubber (weight average molecular weight 600,000, vinyl content 0.04 mol%, phenyl content 8 mol% phenyl vinyl silicone rubber II, Shandong Bito Silicone Co., Ltd.), 1.83 parts by weight of hydroxy silicone oil GT-14 (viscosity 25 mm 2 / s, hydroxyl content of 8.5wt%), 4 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity of 35mm at 25°C) 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%) and 0.05 weight part of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0119] (2) adding 25 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, heating to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), and cooling the rubber material to below 100° C. to obtain a second mixed material;

[0120] (3) Add 2 parts by weight of heat-resistant agent H0 to the second mixed material, continue kneading (pass cooling water, the temperature is 90° C.) for 20 min, discharge the material, cool for more than 30 min, weigh and package to obtain a rubber compound;

[0121] (4) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizing agent. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizing agent in the rubber mix. After passing the mixture through a thin mill for six times, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 2.

[0122] Comparative Example 1

[0123] (1) 100 parts by weight of phenyl vinyl silicone rubber (weight average molecular weight 600,000, vinyl content 0.04 mol%, phenyl content 8 mol% phenyl vinyl silicone rubber II, Shandong Bito Silicone Co., Ltd.), 3 parts by weight of hydroxy silicone oil GT-14 (viscosity 25 mm 2 / s, hydroxyl content of 8.5wt%), 6 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity of 35mm at 25°C) 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%) and 0.05 weight part of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0124] (2) adding 42 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, raising the temperature to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), cooling the rubber material to below 100° C., weighing and packaging to obtain a mixed rubber;

[0125] (3) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizing agent. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizing agent in the rubber mix. After passing the mixture through a thin mill for six times, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 3.

[0126] Comparative Example 2

[0127] The rubber compound was prepared and tested using the same formula and method as in Example 4, except that hexamethyldisilazane was not used. The results are shown in Table 3.

[0128] Comparative Example 3

[0129] The rubber compound was prepared and tested by using the same formula and method as in Example 4, except that 100 parts by weight of phenyl vinyl silicone rubber raw rubber I with a weight average molecular weight of 600,000, a vinyl content of 0.02 mol%, and a phenyl content of 8 mol% was used, Shandong Bito Silicone Co., Ltd. The results are shown in Table 3.

[0130] Comparative Example 4

[0131] (1) 100 parts by weight of phenyl vinyl silicone rubber (weight average molecular weight 600,000, vinyl content 0.02 mol%, phenyl content 8 mol% phenyl vinyl silicone rubber I, Shandong Bito Silicone Co., Ltd.), 1.83 parts by weight of hydroxy silicone oil GT-14 (viscosity 25 mm 2 / s, hydroxyl content of 8.5wt%), 4 parts by weight of hexamethyldisilazane HMDZ, 0.5 parts by weight of vinyl hydroxy silicone oil (viscosity of 35mm at 25°C) 2 / s, hydroxyl content of 6.0wt%, vinyl content of 7.0mol%) and 0.05 weight part of vinyltrimethoxysilane (A-171, Nanjing Nengde New Material Technology Co., Ltd.) were put into a kneader and kneaded for 3-4 hours to obtain a first mixed material;

[0132] (2) adding 25 parts by weight of fumed silica M-5, 0.05 parts by weight of deionized water and 0.07 parts by weight of zinc stearate (Hangzhou Oil Chemical Co., Ltd.) to the first mixed material, heating to 150° C. for high-temperature banburying, keeping the temperature for 2 hours (while removing low molecular weight substances), cooling the rubber material to below 100° C., weighing and packaging to obtain a mixed rubber;

[0133] (3) Take 100 parts by weight of the rubber mix and 1 part by weight of a paste of dipentadienyl vulcanizer. Then, use a 6-inch open mill to evenly mix and disperse the paste of dipentadienyl vulcanizer in the rubber mix. After six passes, a curable silicone rubber composition is prepared. The curable silicone rubber composition is subjected to plate vulcanization at 170°C for 10 minutes (i.e., one-stage vulcanization) and post-vulcanization at 200°C for 4 hours (i.e., two-stage vulcanization). The mechanical properties are tested. The results are shown in Table 3.

[0134] Comparative Example 5

[0135] The rubber compound was prepared and tested using the same formula and method as in Example 8, except that hexamethyldisilazane was not used. The results are shown in Table 3.

[0136] Table 1 Performance of samples of Examples 1-5

[0137]

[0138]

[0139] Table 2 Performance of samples of Examples 6-9

[0140]

[0141] Table 3 Comparative Examples 1-5 Sample Performance

[0142]

[0143]

[0144] It can be seen from Tables 1-3 that the phenyl vinyl silicone rubber composition of the present invention has improved heat resistance, especially after aging at a high temperature of 300° C. for 3 days, the overall performance is good.

[0145] It can be seen from Examples 3-5 and Comparative Example 3 that, compared with Comparative Example 3 in which the vinyl content is outside the scope of the present invention, under thermal aging conditions of 300°C, Examples 3-5 show low change rates of tensile strength and elongation at break, have excellent high temperature resistance, and preferably have a vinyl content of phenyl vinyl silicone rubber in the range of 0.04-0.08 mol%.

[0146] It can be seen from Example 4 and Comparative Example 2, as well as Example 8 and Comparative Example 5 that the silicone rubber prepared by using the structural treatment agent containing silazane improves the high temperature resistance of the material.

[0147] It can be seen from Examples 1-3 and Examples 6-8 that the use of titanium dioxide as a heat-resistant agent in combination with a structural treatment agent containing silazane has excellent high temperature resistance.

Claims

1. A phenyl vinyl silicone rubber composition, wherein: The phenyl vinyl silicone rubber composition comprises 100 parts by weight of phenyl vinyl silicone rubber, 20-50 parts by weight of reinforcing filler, 3-15 parts by weight of structural treatment agent and 1-3 parts by weight of heat-resistant agent; The phenyl content of the phenyl vinyl silicone rubber is 8-15 mol%, and the vinyl content is 0.04-0.25 mol%; the reinforcing filler includes white carbon black; the structural treatment agent includes silazane, hydroxy silicone oil, vinyl hydroxy silicone oil, vinyl trimethoxy silane, zinc stearate and water in a weight ratio of 1:(0.2-0.8):(0.05-0.2):(0.005-0.02):(0.01-0.02):(0.005-0.02).

2. The phenyl vinyl silicone rubber composition according to claim 1, wherein The weight average molecular weight of the phenyl vinyl silicone rubber is 500000-700000; And / or, the phenyl content in the phenyl vinyl silicone rubber is 8-10 mol%; And / or, the vinyl content of the phenyl vinyl silicone rubber is 0.04-0.12 mol%, preferably 0.04-0.08 mol%.

3. The phenyl vinyl silicone rubber composition according to claim 2, wherein The phenyl vinyl silicone rubber includes a first phenyl vinyl silicone rubber and a second phenyl vinyl silicone rubber, the first phenyl vinyl silicone rubber has a vinyl content of 0.04 mol%, the second phenyl vinyl silicone rubber has a vinyl content of 0.08 mol%, and the weight ratio of the first phenyl vinyl silicone rubber to the second phenyl vinyl silicone rubber is 0:100-100:0, preferably 10:90-90:10, more preferably 15:85-85:15, and further preferably 15:85-25:

75.

4. The phenyl vinyl silicone rubber composition according to any one of claims 1 to 3, wherein The specific surface area of ​​the white carbon black is 100-300m 2 / g; And / or, the amount of the structure treating agent is 5-10 parts by weight; And / or, the silazane is hexamethyldisilazane.

5. The phenyl vinyl silicone rubber composition according to any one of claims 1 to 4, wherein The hydroxyl content of the hydroxy silicone oil is above 5wt%, preferably 5wt%-10wt%; the viscosity at 25°C is ≤30mm 2 / s, preferably 10-30mm 2 / s, more preferably 15-25mm 2 / s; And / or, the hydroxy silicone oil is α,γ-dihydroxypolydimethylsilane; And / or, the weight ratio of the silazane to the hydroxy silicone oil is 1:(0.4-0.5).

6. The phenyl vinyl silicone rubber composition according to any one of claims 1 to 5, wherein The vinyl hydroxy silicone oil has a hydroxyl content of 5-7 wt%, for example, 6.0 wt%; a vinyl content of 6-8 mol%, for example, 7.0 mol%; and a viscosity of 30-40 mm at 25°C. 2 / s; And / or, the weight ratio of the silazane to the vinyl hydroxy silicone oil is 1:(0.08-0.15).

7. The phenyl vinyl silicone rubber composition according to any one of claims 1 to 6, wherein The weight ratio of the silazane to the vinyltrimethoxysilane is 1:(0.008-0.015); And / or, the weight ratio of the silazane to water is 1:(0.08-0.15).

8. The phenyl vinyl silicone rubber composition according to any one of claims 1 to 7, wherein The heat-resistant agent is selected from cerium oxide, titanium dioxide and heat-resistant agent H0, preferably titanium dioxide.

9. The method for preparing the phenyl vinyl silicone rubber composition according to any one of claims 1 to 8, wherein: The preparation method comprises the following steps: S1, adding phenyl vinyl silicone rubber, silazane, hydroxy silicone oil, vinyl hydroxy silicone oil and vinyl trimethoxy silane into a kneader for kneading to obtain a first mixed material; S2, adding reinforcing filler, water and zinc stearate to the first mixed material, and kneading at a temperature of 140-160° C. to obtain a second mixed material; S3. Add a heat-resistant agent to the second mixed material, and knead the mixture at 20-90° C. to obtain a phenyl vinyl silicone rubber composition.

10. Silicone rubber, formed by the phenyl vinyl silicone rubber composition according to any one of claims 1 to 8 and a vulcanizing agent, wherein the vulcanizing agent is a dipentane vulcanizing agent, and the weight ratio of the phenyl vinyl silicone rubber composition to the vulcanizing agent is 100:(0.1-5), preferably 100:(0.2-2), and more preferably 100:(0.5-1.5).

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