A self-lubricating vulcanized silicone rubber and a method for preparing the same

Abstract

The application provides a self-lubricating vulcanized silicone rubber, which comprises the following components: methyl vinyl silicone rubber, vinyl silicone oil, PTFE micro powder, fumed silica, diphenylsilanediol, hexamethyldisilazane, molybdenum disulfide, nano cerium oxide, a coupling agent, a silicone internal release agent and a vulcanizing agent, and has the beneficial effects that the PTFE micro powder and the molybdenum disulfide form a synergistic lubricating system, the friction coefficient and the abrasion amount of the silicone rubber are greatly reduced, the coupling agent is used to modify the filler, the interface combination is strengthened, and the mechanical properties of the material are ensured, the nano cerium oxide is used to remove aging free radicals, the thermal oxygen stability of the silicone rubber is significantly improved, and the comprehensive performance is better than that of the prior art.

Description

Technical Field

[0001] This invention relates to the field of silicone rubber, and more particularly to a self-lubricating vulcanized silicone rubber and its preparation method. Background Technology

[0002] Silicone rubber, due to its excellent high and low temperature resistance, electrical insulation, weather resistance, and physiological inertness, is widely used in seals, gaskets, rollers, and guide sleeves in aerospace, electronics, automotive manufacturing, and medical device industries. In these dynamic or static contact applications, silicone rubber materials are required to possess not only good mechanical strength but also a low coefficient of surface friction and excellent wear resistance to reduce friction and wear, lower energy consumption, and extend service life.

[0003] There are two main types of methods to improve the self-lubricating properties of silicone rubber. One type involves adding liquid lubricants such as methyl silicone oil and hydroxyl silicone oil to the rubber compound. This method can reduce the coefficient of friction of the material in the short term, but the lubricating effect is difficult to maintain in the long term and will also contaminate the contact surface. The other type involves adding solid lubricating fillers such as polytetrafluoroethylene, molybdenum disulfide, and graphite. Although this can give the material a long-lasting self-lubricating ability, the solid fillers have poor compatibility with the silicone rubber matrix, and are prone to uneven dispersion and agglomeration, ultimately resulting in a significant reduction in the mechanical properties of the vulcanized rubber. Summary of the Invention

[0004] (a) Technical problems to be solved In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a self-lubricating vulcanized silicone rubber and its preparation method, which solves the technical problems of unstable lubrication effect and easy contamination of contact surface by liquid lubricant, and poor compatibility and uneven dispersion of solid lubricating filler with silicone rubber matrix, which leads to a significant decrease in mechanical properties.

[0005] (II) Technical Solution The purpose of this invention is to provide a self-lubricating vulcanized silicone rubber, comprising the following components in parts by weight: 100 parts of methyl vinyl silicone rubber; Vinyl silicone oil, 0.5–1.5 parts; PTFE micro powder 3-10 parts; Fumed silica, 30-45 parts; Diphenylsilanediol, 1.5–3.5 parts; Hexamethyldisilazane 1.0–3.0 parts; Molybdenum disulfide, 2-8 parts; Nano-cerium oxide, 1.0–4.0 parts; 0.5–2.0 parts of coupling agent; Silicone-based internal release agent: 0.05–0.20 parts; Vulcanizing agent: 1.0 to 2.5 parts.

[0006] Preferably, the methyl vinyl silicone rubber has a vinyl chain molar fraction of 0.15% to 0.20%, and the vinyl silicone oil has a vinyl chain molar fraction of 5% to 6%.

[0007] Preferably, the specific surface area of ​​the fumed silica is 300–350 m². 2 / g.

[0008] Preferably, the PTFE micro powder has a particle size of 1–5 μm; and the molybdenum disulfide has a particle size of 0.5–2 μm.

[0009] On the other hand, the present invention also provides a method for preparing self-lubricating vulcanized silicone rubber, characterized by comprising the following steps: S1. Plasticizing and mixing: Put 100 parts of methyl vinyl silicone rubber into a two-mill or internal mixer and plasticize for 1 to 5 minutes until the rollers are wrapped. Add 0.5 to 1.5 parts of vinyl silicone oil and mix until the rubber compound is uniform and transparent. S2. Modification and Reinforcement: Add 30-45 parts of fumed silica in 2-3 batches, and simultaneously add 1.5-3.5 parts of diphenylsilanediol and 1.0-3.0 parts of hexamethyldisilazane in batches. Control the temperature of the rubber compound between 120℃ and 150℃ throughout the process. Mix for 2-3 minutes after each addition. After adding all the reinforcing fillers, continue mixing for 5-8 minutes until the degree of structure of the rubber compound is significantly reduced and the surface is smooth with no dry powder. S3. Dispersion and Coupling of Solid Lubricating Fillers: Mix 3-10 parts of PTFE micro powder, 2-8 parts of molybdenum disulfide, 1.0-4.0 parts of nano-cerium oxide and 0.5-2.0 parts of coupling agent evenly beforehand and let stand for 10-15 minutes; then add the mixture to the compound in 2-3 portions, mixing for 2-3 minutes at a roller speed of 15-25 r / min after each addition, for a total mixing time of 6-8 minutes, maintaining a roller gap of 1-2 mm and a compound temperature between 50℃ and 70℃. S4. Adding vulcanizing agent: Add 0.05 to 0.20 parts of silicone internal release agent and mix for 3 minutes; finally, add 1.0 to 2.5 parts of vulcanizing agent, control the temperature of the rubber compound between 50℃ and 70℃, and pass through the sheet 6 to 8 times with a roller gap of 0.5 to 1.0 mm before sheeting. S5. Curing: Let the obtained compounded rubber sheet stand at room temperature for 24 hours and store it in a dry and ventilated place; S6. Vulcanization: The cured rubber compound is filled into the mold and vulcanized once on a flat vulcanizing machine at a temperature of 170℃, a pressure of 10-15MPa, and a time of 10min; then it is transferred to an oven for a second vulcanization at a temperature of 190-200℃ and a time of 2-3h to obtain the self-lubricating vulcanized silicone rubber.

[0010] (III) Beneficial Effects First, PTFE micro powder and molybdenum disulfide are compounded to construct a synergistic lubrication system. PTFE micro powder forms a low-friction interface on the rubber surface, and molybdenum disulfide generates a transfer lubrication film through interlayer slippage, giving the vulcanized rubber a durable and stable low-friction performance with a friction coefficient as low as 0.29 and Akron wear of only 0.19 cm³, which far exceeds the performance of ordinary silicone rubber. Furthermore, by pretreating PTFE micropowder, molybdenum disulfide, and nano-cerium oxide with a coupling agent, the interfacial bonding force between the filler and the silicone rubber matrix is ​​improved, preventing stress concentration and mechanical property degradation caused by filler agglomeration. The tensile strength of the finished product reaches 8.1. With an elongation at break of 420%, it combines self-lubricating properties with excellent mechanical properties. In addition, the addition of nano-cerium oxide as a heat-resistant stabilizer can capture free radicals generated by thermo-oxidative aging, inhibit the oxidative crosslinking of silicone rubber side chains and the breakage of the main chain. After the material is aged in hot air at 200℃ for 72 hours, the change rate of tensile strength is the lowest -11.2% and the change rate of elongation at break is the lowest -12.2%. The heat aging resistance is significantly better than the existing technology without this component. Detailed Implementation

[0011] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0012] This application provides the following four embodiments, as detailed below: Example 1

[0013] A self-lubricating vulcanized silicone rubber, comprising the following components by weight: 100 parts of methyl vinyl silicone rubber; Vinyl silicone oil 0.5 parts; 3 parts PTFE micro powder; 30 parts of fumed silica; 1.5 parts of diphenylsilanediol; Hexamethyldisilazane 1.0 part; Two parts of molybdenum disulfide; 1.0 part of nano-cerium oxide; 0.5 parts coupling agent; Silicone-based internal release agent, 0.05 parts; Vulcanizing agent 1.0 part.

[0014] In this embodiment, the vinyl chain molar fraction of the methyl vinyl silicone rubber is 0.15% to 0.20%, and the vinyl chain molar fraction of the vinyl silicone oil is 5% to 6%.

[0015] In this embodiment, the specific surface area of ​​the fumed silica is 300-350 m² / g.

[0016] In this embodiment, the particle size of the PTFE micro powder is 1-5 μm; the particle size of the molybdenum disulfide is 0.5-2 μm.

[0017] In this embodiment, the vulcanizing agent is vulcanizing agent bis-25, the coupling agent is silane coupling agent KH-171, and the silicone internal release agent is organosilicone wax modified polysiloxane.

[0018] The preparation method of this embodiment includes the following steps: S1. Plasticizing and mixing: Put 100 parts of methyl vinyl silicone rubber into a two-mill or internal mixer, plasticize for 2 minutes until the rollers are wrapped, add 0.5 parts of vinyl silicone oil, and mix until the rubber compound is uniform and transparent; S2. Modification and Reinforcement: Add 30 parts of fumed silica in 3 batches, and simultaneously add 1.5 parts of diphenylsilanediol and 1.0 part of hexamethyldisilazane in batches. Control the temperature of the rubber compound between 120℃ and 150℃ throughout the process. Mix for 2 minutes after each addition. After adding all the reinforcing fillers, continue mixing for 8 minutes until the degree of structure of the rubber compound is significantly reduced and the surface is smooth with no dry powder. S3. Dispersion and Coupling of Solid Lubricating Fillers: Mix 3 parts PTFE micro powder, 2 parts molybdenum disulfide, 1.0 part nano cerium oxide and 0.5 parts coupling agent evenly beforehand and let stand for 10 minutes; then add them to the compound in two batches. After each addition, mix at a roller speed of 20 r / min for 3 minutes, for a total mixing time of 7 minutes, keeping the roller gap at 1-2 mm and the compound temperature at 60℃. S4. Adding vulcanizing agent: Add 0.05 parts of silicone internal release agent and mix for 3 minutes; finally add 1.0 part of vulcanizing agent, control the rubber temperature at 50℃, and pass through the sheet 6 to 8 times with a roller gap of 0.5 to 1.0 mm before sheeting. S5. Curing: Let the obtained compounded rubber sheet stand at room temperature for 24 hours and store it in a dry and ventilated place; S6. Vulcanization: The cured rubber compound is filled into the mold and vulcanized once on a flat vulcanizing machine at a vulcanization temperature of 170℃ and a pressure of 10-15. The curing process is carried out for 10 minutes; then transferred to an oven for secondary vulcanization at 190-200℃ for 2.5 hours to obtain the self-lubricating vulcanized silicone rubber. Example 2

[0019] A self-lubricating vulcanized silicone rubber, comprising the following components by weight: 100 parts of methyl vinyl silicone rubber; Vinyl silicone oil 1.0 part; 6 parts PTFE micro powder; 38 parts of fumed silica; 2.5 parts of diphenylsilanediol; Hexamethyldisilazane 2.0 parts; 5 parts of molybdenum disulfide; 2.5 parts of nano-cerium oxide; 1.2 parts coupling agent; Silicone-based internal release agent, 0.12 parts; Vulcanizing agent 1.8 parts.

[0020] In this embodiment, the vinyl chain molar fraction of the methyl vinyl silicone rubber is 0.15% to 0.20%, and the vinyl chain molar fraction of the vinyl silicone oil is 5% to 6%.

[0021] In this embodiment, the specific surface area of ​​the fumed silica is 300-350 m² / g.

[0022] In this embodiment, the particle size of the PTFE micro powder is 1-5 μm; the particle size of the molybdenum disulfide is 0.5-2 μm.

[0023] In this embodiment, the vulcanizing agent is vulcanizing agent bis-25, the coupling agent is silane coupling agent KH-171, and the silicone internal release agent is organosilicone wax modified polysiloxane.

[0024] The preparation method of this embodiment includes the following steps: S1. Plasticizing and mixing: Put 100 parts of methyl vinyl silicone rubber into a two-mill or internal mixer, plasticize for 3 minutes until the rollers are wrapped, add 1.0 part of vinyl silicone oil, and mix until the rubber compound is uniform and transparent; S2. Modification and Reinforcement: Add 38 parts of fumed silica in two batches, and simultaneously add 2.5 parts of diphenylsilanediol and 2.0 parts of hexamethyldisilazane in batches. Control the temperature of the rubber compound between 120℃ and 150℃ throughout the process. Mix for 3 minutes after each addition. After adding all the reinforcing fillers, continue mixing for 5 minutes until the degree of structure of the rubber compound is significantly reduced and the surface is smooth with no dry powder. S3. Dispersion and Coupling of Solid Lubricating Fillers: 6 parts PTFE micro powder, 5 parts molybdenum disulfide, 2.5 parts nano cerium oxide and 1.2 parts coupling agent are premixed evenly and allowed to stand for 12 minutes; then added to the compound in two batches, and after each addition, the mixture is mixed at a roller speed of 25 r / min for 3 minutes, for a total mixing time of 8 minutes, while maintaining a roller gap of 1-2 mm and a compound temperature of 65℃; S4. Adding vulcanizing agent: Add 0.12 parts of silicone internal release agent and mix for 3 minutes; finally add 1.8 parts of vulcanizing agent, control the rubber temperature at 60℃, and pass through the sheet 6 to 8 times with a roller gap of 0.5 to 1.0 mm before sheeting. S5. Curing: Let the obtained compounded rubber sheet stand at room temperature for 24 hours and store it in a dry and ventilated place; S6. Vulcanization: The cured rubber compound is filled into the mold and vulcanized once on a flat vulcanizing machine at a vulcanization temperature of 170℃ and a pressure of 10-15. The curing process is carried out for 10 minutes; then transferred to an oven for secondary vulcanization at 190-200℃ for 2.5 hours to obtain the self-lubricating vulcanized silicone rubber. Example 3

[0025] A self-lubricating vulcanized silicone rubber, comprising the following components by weight: 100 parts of methyl vinyl silicone rubber; Vinyl silicone oil 1.5 parts; 10 parts PTFE micro powder; 45 parts of fumed silica; Diphenylsilanediol 3.5 parts; Hexamethyldisilazane 3.0 parts; 8 parts of molybdenum disulfide; 4.0 parts of nano-cerium oxide; 2.0 parts of coupling agent; Silicone-based internal mold release agent, 0.2 parts; 2.5 parts of vulcanizing agent.

[0026] In this embodiment, the vinyl chain molar fraction of the methyl vinyl silicone rubber is 0.15% to 0.20%, and the vinyl chain molar fraction of the vinyl silicone oil is 5% to 6%.

[0027] In this embodiment, the specific surface area of ​​the fumed silica is 300-350 m² / g.

[0028] In this embodiment, the particle size of the PTFE micro powder is 1-5 μm; the particle size of the molybdenum disulfide is 0.5-2 μm.

[0029] In this embodiment, the vulcanizing agent is vulcanizing agent bis-25, the coupling agent is silane coupling agent KH-171, and the silicone internal release agent is organosilicone wax modified polysiloxane.

[0030] The preparation method of this embodiment includes the following steps: S1. Plasticizing and mixing: Put 100 parts of methyl vinyl silicone rubber into a two-mill or internal mixer, plasticize for 3 minutes until the rollers are wrapped, add 1.5 parts of vinyl silicone oil, and mix until the rubber compound is uniform and transparent; S2. Modification and Reinforcement: Add 45 parts of fumed silica in two batches, and simultaneously add 3.5 parts of diphenylsilanediol and 3.0 parts of hexamethyldisilazane in batches. Control the temperature of the rubber compound between 120℃ and 150℃ throughout the process. Mix for 3 minutes after each addition. After adding all the reinforcing fillers, continue mixing for 5 minutes until the degree of structure of the rubber compound is significantly reduced and the surface is smooth with no dry powder. S3. Dispersion and Coupling of Solid Lubricating Fillers: 10 parts of PTFE micro powder, 8 parts of molybdenum disulfide, 4.0 parts of nano-cerium oxide and 2.0 parts of coupling agent are premixed evenly and allowed to stand for 12 minutes; then added to the compound in two batches, and after each addition, the mixture is mixed at a roller speed of 25 r / min for 3 minutes, for a total mixing time of 8 minutes, while maintaining a roller gap of 1-2 mm and a compound temperature of 65℃; S4. Adding vulcanizing agent: Add 0.2 parts of silicone internal release agent and mix for 3 minutes; finally add 2.5 parts of vulcanizing agent, control the rubber temperature at 60℃, and pass through the sheet 6 to 8 times with a roller gap of 0.5 to 1.0 mm before sheeting. S5. Curing: Let the obtained compounded rubber sheet stand at room temperature for 24 hours and store it in a dry and ventilated place; S6. Vulcanization: The cured rubber compound is filled into the mold and vulcanized once on a flat vulcanizing machine at a vulcanization temperature of 170℃ and a pressure of 10-15. The curing process is carried out for 10 minutes; then transferred to an oven for secondary vulcanization at 190-200℃ for 2.5 hours to obtain the self-lubricating vulcanized silicone rubber. Example 4

[0031] A self-lubricating vulcanized silicone rubber, comprising the following components by weight: 100 parts of methyl vinyl silicone rubber; Vinyl silicone oil 1.2 parts; 6.0 parts of PTFE micro powder; 35 parts of fumed silica; Diphenylsilanediol 2.0 parts; 1.5 parts of hexamethyldisilazane; 6.0 parts of molybdenum disulfide; Nano-cerium oxide, 2.0 parts; 1.0 part of coupling agent; Silicone-based internal mold release agent, 0.1 parts; Vulcanizing agent 1.5 parts.

[0032] In this embodiment, the vinyl chain molar fraction of the methyl vinyl silicone rubber is 0.15% to 0.20%, and the vinyl chain molar fraction of the vinyl silicone oil is 5% to 6%.

[0033] In this embodiment, the specific surface area of ​​the fumed silica is 300-350 m² / g.

[0034] In this embodiment, the particle size of the PTFE micro powder is 1-5 μm; the particle size of the molybdenum disulfide is 0.5-2 μm.

[0035] In this embodiment, the vulcanizing agent is vulcanizing agent bis-25, the coupling agent is silane coupling agent KH-171, and the silicone internal release agent is organosilicone wax modified polysiloxane.

[0036] The preparation method of this embodiment includes the following steps: S1. Plasticizing and mixing: Put 100 parts of methyl vinyl silicone rubber into a two-mill or internal mixer and plasticize for 5 minutes until the rollers are wrapped. Add 1.2 parts of vinyl silicone oil and mix until the rubber compound is uniform and transparent. S2. Modification and Reinforcement: Add 35 parts of fumed silica in two batches, and simultaneously add 2.0 parts of diphenylsilanediol and 1.5 parts of hexamethyldisilazane in batches. Control the temperature of the rubber compound between 120℃ and 150℃ throughout the process. Mix for 3 minutes after each addition. After adding all the reinforcing fillers, continue mixing for 8 minutes until the degree of structure of the rubber compound is significantly reduced and the surface is smooth with no dry powder. S3. Dispersion and Coupling of Solid Lubricating Fillers: Mix 8 parts PTFE micro powder, 8 parts molybdenum disulfide, 2.0 parts nano cerium oxide and 1.0 part coupling agent evenly beforehand and let stand for 15 minutes; then add them to the compound in two batches. After each addition, mix at a roller speed of 25 r / min for 3 minutes, for a total mixing time of 6 minutes, keeping the roller gap at 1-2 mm and the compound temperature at 70℃. S4. Adding vulcanizing agent: Add 0.1 parts of silicone internal release agent and mix for 3 minutes; finally add 1.5 parts of vulcanizing agent, control the rubber temperature at 70℃, and pass through the sheet 6 to 8 times with a roller gap of 0.5 to 1.0 mm before sheeting. S5. Curing: Let the obtained compounded rubber sheet stand at room temperature for 24 hours and store it in a dry and ventilated place; S6. Vulcanization: The cured rubber compound is filled into the mold and vulcanized once on a flat vulcanizing machine at a vulcanization temperature of 170℃ and a pressure of 10-15. The curing process is carried out for 10 minutes; then transferred to an oven for secondary vulcanization at 190-200℃ for 2 hours to obtain the self-lubricating vulcanized silicone rubber.

[0037] The silicone rubber products prepared in Examples 1 to 4 were subjected to the following performance tests, and the results are shown in the table below:

[0038] Results analysis: Based on the test results of the four embodiments, the comprehensive performance of the self-lubricating vulcanized silicone rubber of the present invention is as follows: With the increase of PTFE micropowder and molybdenum disulfide content, the coefficient of friction and wear of the material significantly decrease. In Example 3 (10 parts PTFE, 8 parts molybdenum disulfide), the coefficient of friction is as low as 0.29, and the Akron wear is only 0.19 cm³, exhibiting the best self-lubricating and wear-resistant properties. Furthermore, the reasonable ratio of reinforcing filler and lubricating filler affects the mechanical properties; Example 2 (38 parts fumed silica, 6 parts PTFE, 5 parts molybdenum disulfide) reaches the highest tensile strength of 8.1. With an elongation at break of 380%, it balances reinforcement and lubrication. In terms of heat aging resistance, the higher the content of nano-cerium oxide, the better the performance retention rate after aging. After hot air aging at 200℃ for 72h, the change rates of tensile strength and elongation at break in Example 3 were -10.1% and -12.4%, respectively, which are better than other examples. Overall, Examples 2 and 4 achieved a good balance between mechanical properties, lubrication properties and processing adaptability, and are more suitable for actual dynamic sealing and roller applications, while Example 3 is suitable for harsh working conditions such as high temperature and high speed friction.

[0039] Although embodiments of the present invention have been shown above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications and variations to the above embodiments, but such modifications are all included within the broad scope of the foregoing disclosure, drawings and claims.

Claims

1. A self-lubricating vulcanized silicone rubber, characterized in that, Based on parts by weight, it comprises the following components: 100 parts of methyl vinyl silicone rubber; Vinyl silicone oil, 0.5–1.5 parts; PTFE micro powder 3-10 parts; Fumed silica, 30-45 parts; Diphenylsilanediol, 1.5–3.5 parts; Hexamethyldisilazane 1.0–3.0 parts; Molybdenum disulfide, 2-8 parts; Nano-cerium oxide, 1.0–4.0 parts; 0.5–2.0 parts of coupling agent; Silicone-based internal release agent: 0.05–0.20 parts; Vulcanizing agent: 1.0 to 2.5 parts.

2. The self-lubricating vulcanized silicone rubber according to claim 1, characterized in that, The methyl vinyl silicone rubber has a vinyl chain molar fraction of 0.15% to 0.20%; the vinyl silicone oil has a vinyl chain molar fraction of 5% to 6%.

3. The self-lubricating vulcanized silicone rubber according to claim 1, characterized in that, The specific surface area of ​​the fumed silica is 300–350 m². 2 / g.

4. The self-lubricating vulcanized silicone rubber according to claim 1, characterized in that, The PTFE micro powder has a particle size of 1–5 μm; the molybdenum disulfide has a particle size of 0.5–2 μm.

5. A method for preparing the self-lubricating vulcanized silicone rubber according to any one of claims 1 to 4, characterized in that, Includes the following steps: S1. Plasticizing and mixing: Put 100 parts of methyl vinyl silicone rubber into a two-mill or internal mixer and plasticize for 1 to 5 minutes until the rollers are wrapped. Add 0.5 to 1.5 parts of vinyl silicone oil and mix until the rubber compound is uniform and transparent. S2. Modification and Reinforcement: Add 30-45 parts of fumed silica in 2-3 batches, and simultaneously add 1.5-3.5 parts of diphenylsilanediol and 1.0-3.0 parts of hexamethyldisilazane in batches. Control the temperature of the rubber compound between 120℃ and 150℃ throughout the process. Mix for 2-3 minutes after each addition. After adding all the reinforcing fillers, continue mixing for 5-8 minutes until the degree of structure of the rubber compound is significantly reduced and the surface is smooth with no dry powder. S3. Dispersion and Coupling of Solid Lubricating Fillers: Mix 3-10 parts of PTFE micro powder, 2-8 parts of molybdenum disulfide, 1.0-4.0 parts of nano-cerium oxide and 0.5-2.0 parts of coupling agent evenly beforehand and let stand for 10-15 minutes; then add the mixture to the compound in 2-3 portions, mixing for 2-3 minutes at a roller speed of 15-25 r / min after each addition, for a total mixing time of 6-8 minutes, maintaining a roller gap of 1-2 mm and a compound temperature between 50℃ and 70℃. S4. Adding vulcanizing agent: Add 0.05 to 0.20 parts of silicone internal release agent and mix for 3 minutes; finally, add 1.0 to 2.5 parts of vulcanizing agent, control the temperature of the rubber compound between 50℃ and 70℃, and pass through the sheet 6 to 8 times with a roller gap of 0.5 to 1.0 mm before sheeting. S5. Curing: Let the obtained compounded rubber sheet stand at room temperature for 24 hours and store it in a dry and ventilated place; S6. Vulcanization: The cured rubber compound is filled into the mold and vulcanized once on a flat vulcanizing machine at a temperature of 170℃, a pressure of 10-15MPa, and a time of 10min; then it is transferred to an oven for a second vulcanization at a temperature of 190-200℃ and a time of 2-3h to obtain the self-lubricating vulcanized silicone rubber.

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