High-strength anti-aging rubber sealing ring and preparation method thereof

Abstract

The application discloses a high-strength anti-aging rubber sealing ring and a preparation method thereof, and belongs to the technical field of sealing rings. The self-synthesized expanded dispersion filler is used as a reinforcing phase to endow the rubber sealing ring with excellent mechanical properties. The expanded dispersion filler has a core-shell structure, the core layer is expanded graphite, and the shell layer is brush-shaped silicon dioxide. The composite structure can disperse stress by generating relative slip, the brush-shaped silicon dioxide can physically block oxygen and heat, reduces the penetration of oxygen into the rubber interior under high temperature, and delays the oxidation and rupture of rubber molecular chains. When the high-strength anti-aging rubber sealing ring is used in a high-temperature scene, the expanded dispersion filler can expand, the expansion effect can fill the tiny cracks and pores of the rubber matrix caused by thermal expansion and cold shrinkage, and the penetration of oxygen and heat aging factors into the rubber interior is reduced.

Description

Technical Field

[0001] This invention belongs to the field of sealing ring technology, specifically a high-strength, aging-resistant rubber sealing ring and its preparation method. Background Technology

[0002] A rubber seal is an annular cover composed of one or more parts, fixed to one ring or washer of a bearing and contacting or forming a narrow labyrinth gap with another ring or washer, serving to prevent lubricating oil leakage and foreign object intrusion. With the rapid development of the automotive industry, the demand for rubber seals used on components such as cylinders and pistons in automotive engines is increasing daily. These rubber seals not only need to achieve a barrier sealing function, but also, because the sealed medium is fuel or lubricating oil, require properties such as oil resistance, high temperature resistance, and good elasticity.

[0003] Existing rubber seals primarily use materials such as nitrile rubber, fluororubber, or neoprene rubber. Fluororubber offers good chemical resistance, oxidation resistance, high-temperature resistance, and wear resistance, but its cost is high. Neoprene rubber possesses exceptional weather resistance and heat resistance, maintaining stable physical and mechanical properties within a temperature range of -40℃ to 120℃. Nitrile rubber exhibits high-temperature resistance, oil resistance, wear resistance, aging resistance, and high sealing performance, making it the most widely used and lowest-cost rubber seal in media such as gasoline and silicone lubricating oil. However, it also suffers from drawbacks such as poor elasticity and poor UV resistance. In industrial production and equipment operation, rubber seals, as core components for achieving sealing functions, directly affect the safety and efficiency of the entire system. Therefore, developing rubber seals with excellent aging resistance has become a key direction for addressing industry pain points and meeting practical application needs.

[0004] Chinese patent announcement CN120718358B discloses an aging-resistant rubber sealing ring and its preparation method. In this method, modified carbon nanotubes are prepared to improve the aging resistance of the rubber sealing ring. However, the aging resistance of this method is limited and its long-term performance under complex aging environments such as high temperature and humid heat is insufficient. Summary of the Invention

[0005] The purpose of this invention is to provide a high-strength, aging-resistant rubber sealing ring and its preparation method. By using a self-synthesized expandable dispersion filler as a reinforcing phase, the rubber sealing ring is endowed with excellent mechanical properties. The expandable dispersion filler has a core-shell structure, with expanded graphite as the core layer and brush-shaped silica as the shell layer. This composite structure can disperse stress by generating relative slip, and the brush-shaped silica can physically block oxygen and heat, reduce oxygen penetration into the rubber interior at high temperatures, and delay the oxidative breakage of rubber molecular chains.

[0006] The objective of this invention can be achieved through the following technical solutions: A method for preparing a high-strength, aging-resistant rubber sealing ring includes the following steps: Step 1: Natural flake graphite is intercalated using potassium permanganate as an oxidant and perchloric acid and ammonium nitrate as intercalating agents to obtain expanded graphite; expanded graphite composite silica is prepared by depositing silica nanorods on the surface of expanded graphite using hexadecyltrimethylammonium bromide as a template agent and tetraethyl orthosilicate as a silicon source via sol-gel method.

[0007] Step 2: Using silica nanorods on the surface of expanded graphite composite silica as growth sites, silica is again directionally grown into a brush-like nanostructure using the sol-gel method to obtain expanded graphite composite silica.

[0008] Step 3: γ-aminopropyltriethoxysilane is first hydrolyzed in a water and ethanol system and then chemically bonded to the hydroxyl groups of expanded graphite composite silica to obtain an expanded dispersion filler.

[0009] Step 4: Mix nitrile rubber and chloroprene rubber at a mass ratio of 80-90:60-70 and then plasticize for 15-17 minutes to obtain plasticized rubber. Mix the plasticized rubber, expanded dispersion filler, antioxidant RD, stearic acid, dibutyl phthalate, zinc oxide, dicumyl peroxide and accelerator M for 4-5 minutes, put it into a mold and vulcanize to obtain a high-strength aging-resistant rubber sealing ring.

[0010] Furthermore, the ratio of the amount of plasticized rubber, expanded dispersion filler, antioxidant RD, stearic acid, dibutyl phthalate, zinc oxide, dicumyl peroxide and accelerator Md is 140-150g: 18-20g: 3-4g: 2-3g: 8-9g: 4-5g: 3-4g: 2-3g.

[0011] Furthermore, the specific preparation steps of expanded graphite are as follows: Natural flake graphite, potassium permanganate, perchloric acid, and ammonium nitrate were added to a reaction vessel at a mass ratio of 1:0.42-0.45:7-8:0.10-0.12. The mixture was stirred for 15-20 minutes at 20-25℃ and 500-600 rpm. After filtration, the precipitate was washed 2-4 times with deionized water until the pH value was 6.0-6.17. The precipitate was then vacuum dried at 60-70℃ for 4-5 hours to obtain expanded graphite.

[0012] Furthermore, the specific preparation steps of expanded graphite composite silica are as follows: Expanded graphite, hexadecyltrimethylammonium bromide, and ammonia were added to a reaction vessel and stirred for 30-40 minutes at 20-25°C and 500-600 rpm. Then, tetraethyl orthosilicate was added, and the reaction was continued for 6-7 hours. The mixture was centrifuged at 8000-8200 rpm for 5-8 minutes, heated to 80-82°C, and then isopropanol and ammonium nitrate were added. The mixture was stirred for 24-26 hours to remove the template agent. The mixture was then freeze-dried under vacuum at -20°C for 12-14 hours to obtain expanded graphite composite silica.

[0013] Furthermore, the ratio of expanded graphite, hexadecyltrimethylammonium bromide, ammonia, tetraethyl orthosilicate, isopropanol, and ammonium nitrate is 70-75g: 5.6-5.8g: 1.4-1.5L: 24-26mL: 500-600mL: 3-4g.

[0014] Furthermore, the specific preparation steps of expanded graphite composite brush-shaped silica are as follows: Hexadecyltrimethylammonium bromide, urea, expanded graphite composite silica, and deionized water were added to a reaction vessel and stirred for 30-40 min at 20-25℃ and 500-600 r / min. Then, cyclohexane, isopropanol, and tetraethyl orthosilicate were added, and stirring was continued for another 30-40 min. The mixture was then heated to 70-74℃ and stirred for 16-18 h. After filtration, the precipitate was washed 2-4 times with deionized water and anhydrous ethanol and dried under vacuum at 60-70℃ for 1-2 h to obtain expanded graphite composite brush-like silica.

[0015] Furthermore, the ratio of hexadecyltrimethylammonium bromide, urea, expanded graphite composite silica, deionized water, cyclohexane, isopropanol, and tetraethyl orthosilicate is 5-6g: 3-3.5g: 50-60g: 1.5-1.8L: 150-170mL: 46-48mL: 10-12mL.

[0016] Furthermore, the specific preparation steps for the expandable dispersion packing are as follows: Expanded graphite composite brush-shaped silica, deionized water, and anhydrous ethanol were added to a reaction vessel and stirred for 12-14 minutes at 20-25℃ and 500-600 r / min. Then, a mixed solution was added, and stirring was continued for 2-3 hours. After the reaction was completed, the product was vacuum filtered using a circulating water multi-purpose vacuum pump. The filter cake was washed 2-4 times with deionized water and anhydrous ethanol and vacuum dried at 60-70℃ for 1-2 hours to obtain the expanded dispersion packing.

[0017] Furthermore, the ratio of expanded graphite composite brush-shaped silica, deionized water, anhydrous ethanol, and the mixed solution is 30-40g: 20-25mL: 60-70mL: 300-320mL.

[0018] Furthermore, the specific steps for preparing the mixed solution are as follows: Deionized water, anhydrous ethanol, and γ-aminopropyltriethoxysilane were added to a reaction vessel and stirred for 40-50 minutes at 20-25°C and 500-600 r / min to obtain a mixed solution.

[0019] Furthermore, the ratio of deionized water, anhydrous ethanol, and γ-aminopropyltriethoxysilane is 30-40 mL: 300-340 mL: 30-40 mL.

[0020] The beneficial effects of this invention are: 1. The high-strength, aging-resistant rubber sealing ring of the present invention uses a self-synthesized expandable dispersion filler as a reinforcing phase, which endows the rubber sealing ring with excellent mechanical properties. The expandable dispersion filler has a core-shell structure, with expanded graphite as the core layer and brush-shaped silica as the shell layer. This composite structure can disperse stress by generating relative slippage. The brush-shaped silica can physically block oxygen and heat, reduce oxygen penetration into the rubber interior at high temperatures, and delay the oxidative breakage of rubber molecular chains.

[0021] 2. The high-strength, aging-resistant rubber sealing ring prepared by this invention is dispersed by γ-aminopropyltriethoxysilane using an expanded dispersion filler, which improves its compatibility with the rubber matrix, avoids agglomeration when used as a reinforcing phase, and prevents agglomeration from forming void defects. In conjunction with the special structure of expanded graphite composite brush-like silica, a continuous physical barrier layer can be formed to prevent rapid penetration of oil media and improve oil resistance.

[0022] 3. When the high-strength, aging-resistant rubber sealing ring prepared by this invention is used in high-temperature environments, its composition contains an expandable dispersing filler. The expandable dispersing filler can exert an expansion effect, which fills the tiny cracks and pores in the rubber matrix caused by thermal expansion and contraction, reduces the penetration of oxygen and heat aging factors into the rubber interior, delays the oxidative breakage of the rubber molecular chains, and can offset thermal stress to avoid structural damage. Rubber is prone to softening and shrinking at high temperatures. The expansion of the filler can compensate for this volume change, release internal thermal stress, prevent the rubber molecular chains from breaking due to stress concentration, delay accelerated aging, and the expansion effect can squeeze the brush-like silica in the shell layer, causing it to penetrate into the rubber matrix, reduce interfacial voids, and improve the bonding force with the rubber matrix. Attached Figure Description

[0023] Figure 1 This is a SEM image of natural flake graphite in Example 3.

[0024] Figure 2 This is a SEM image of the expanded graphite in Example 3.

[0025] Figure 3This is a SEM image of expanded graphite composite silica in Example 3.

[0026] Figure 4 This is a SEM image of the expanded graphite composite brush-shaped silica in Example 3. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] Example 1: A method for preparing a high-strength, aging-resistant rubber sealing ring, comprising the following steps: S1: Natural flake graphite, potassium permanganate, perchloric acid and ammonium nitrate were added to a reaction vessel in a mass ratio of 1:0.42:7:0.10. The mixture was stirred for 15 min at 20℃ and 500 r / min, filtered, and the precipitate was washed twice with deionized water until the pH value was 6.0. The precipitate was then vacuum dried at 60℃ for 4 h to obtain expanded graphite.

[0029] S2: Add 70g of expanded graphite, 5.6g of hexadecyltrimethylammonium bromide and 1.4L of ammonia water to a reaction vessel, stir for 30min at 20℃ and 500r / min, then add 24mL of tetraethyl orthosilicate, continue the reaction for 6h, centrifuge at 8000r / min for 5min, heat to 80℃, then add 500mL of isopropanol and 3g of ammonium nitrate, continue stirring for 24h to remove the template agent, and freeze-dry under vacuum at -20℃ for 12h to obtain expanded graphite composite silica.

[0030] S3: Add 5g hexadecyltrimethylammonium bromide, 3g urea, 50g expanded graphite composite silica and 1.5L deionized water to a reaction vessel, stir for 30min at 20℃ and 500r / min, then add 150mL cyclohexane, 46mL isopropanol and 10mL tetraethyl orthosilicate, continue stirring for 30min, heat to 70℃ and continue stirring for 16h, filter, wash the precipitate twice with deionized water and anhydrous ethanol, and vacuum dry at 60℃ for 1h to obtain expanded graphite composite brush-like silica.

[0031] S4: Add 30 mL of deionized water, 300 mL of anhydrous ethanol and 30 mL of γ-aminopropyltriethoxysilane to the reaction vessel and stir for 40 min at 20 °C and 500 r / min to obtain a mixed solution; add 30 g of expanded graphite composite brush-shaped silica, 20 mL of deionized water and 60 mL of anhydrous ethanol to the reaction vessel and stir for 12 min at 20 °C and 500 r / min, then add 300 mL of the mixed solution and continue stirring for 2 h. After the reaction is completed, vacuum filter the product using a circulating water multi-purpose vacuum pump, wash the filter cake twice with deionized water and anhydrous ethanol, and vacuum dry at 60 °C for 1 h to obtain the expanded dispersion packing.

[0032] S5: Mix 80g of nitrile rubber and 60g of chloroprene rubber, and then plasticize at 40℃ and 40r / min for 15min to obtain plasticized rubber; mix 140g of plasticized rubber, 18g of expanded dispersion filler, 3g of antioxidant RD, 2g of stearic acid, 8g of plasticizer dibutyl phthalate, 4g of zinc oxide, 3g of dicumyl peroxide and 2g of accelerator M for 4min, put it into a mold, and vulcanize at 140℃ for 10min to obtain a high-strength aging-resistant rubber sealing ring.

[0033] Example 2: A method for preparing a high-strength, aging-resistant rubber sealing ring, comprising the following steps: S1: Natural flake graphite, potassium permanganate, perchloric acid and ammonium nitrate were added to a reaction vessel in a mass ratio of 1:0.435:7.5:0.11. The mixture was stirred at 22.5℃ and 550r / min for 17.5 min, filtered, and the precipitate was washed three times with deionized water until the pH value was 6.085. The precipitate was then dried under vacuum at 65℃ for 4.5 h to obtain expanded graphite.

[0034] S2: 72.5g expanded graphite, 5.7g hexadecyltrimethylammonium bromide and 1.45L ammonia water were added to a reaction vessel and stirred at 22.5℃ and 550r / min for 35min. Then 25mL tetraethyl orthosilicate was added and the reaction was continued for 6.5h. The mixture was centrifuged at 8100r / min for 6.5min, heated to 81℃, and then 550mL isopropanol and 3.5g ammonium nitrate were added. The mixture was stirred for 25h to remove the template agent. The mixture was then freeze-dried under vacuum at -20℃ for 13h to obtain expanded graphite composite silica.

[0035] S3: Add 5.5g hexadecyltrimethylammonium bromide, 3.25g urea, 55g expanded graphite composite silica and 1.65L deionized water to a reaction vessel and stir for 35min at 22.5℃ and 550r / min. Then add 160mL cyclohexane, 47mL isopropanol and 11mL tetraethyl orthosilicate and continue stirring for 35min. Heat to 72℃ and continue stirring for 17h. Filter and wash the precipitate three times with deionized water and anhydrous ethanol. Dry under vacuum at 65℃ for 1.5h to obtain expanded graphite composite brush-like silica.

[0036] S4: Add 35 mL of deionized water, 320 mL of anhydrous ethanol, and 35 mL of γ-aminopropyltriethoxysilane to a reaction vessel and stir for 45 min at 22.5 °C and 550 r / min to obtain a mixed solution. Add 35 g of expanded graphite composite brush-shaped silica, 22.5 mL of deionized water, and 65 mL of anhydrous ethanol to a reaction vessel and stir for 13 min at 22.5 °C and 550 r / min. Then add 310 mL of the mixed solution and continue stirring for 2.5 h. After the reaction is complete, vacuum filter the product using a circulating water multi-purpose vacuum pump. Wash the filter cake three times with deionized water and anhydrous ethanol and vacuum dry at 65 °C for 1.5 h to obtain the expanded dispersion packing.

[0037] S5: Mix 85g of nitrile rubber and 65g of chloroprene rubber, and then plasticize at 42.5℃ and 45r / min for 16min to obtain plasticized rubber; mix 145g of plasticized rubber, 19g of expanded dispersion filler, 3.5g of antioxidant RD, 2.5g of stearic acid, 8.5g of plasticizer dibutyl phthalate, 4.5g of zinc oxide, 3.5g of dicumyl peroxide and 2.5g of accelerator M for 4.5min, put into a mold, and vulcanize at 145℃ for 12.5min to obtain a high-strength aging-resistant rubber sealing ring.

[0038] Example 3: A method for preparing a high-strength, aging-resistant rubber sealing ring, comprising the following steps: S1: Natural flake graphite, potassium permanganate, perchloric acid and ammonium nitrate were added to a reaction vessel in a mass ratio of 1:0.45:8:0.12. The mixture was stirred for 20 min at 25 °C and 600 r / min. After filtration, the precipitate was washed four times with deionized water until the pH value was 6.17. The precipitate was then vacuum dried at 70 °C for 5 h to obtain expanded graphite.

[0039] S2: Add 75g of expanded graphite, 5.8g of hexadecyltrimethylammonium bromide and 1.5L of ammonia water to a reaction vessel, stir for 40min at 25℃ and 600r / min, then add 26mL of tetraethyl orthosilicate, continue the reaction for 7h, centrifuge at 8200r / min for 8min, heat to 82℃, then add 600mL of isopropanol and 4g of ammonium nitrate, continue stirring for 26h to remove the template agent, and freeze-dry under vacuum at -20℃ for 14h to obtain expanded graphite composite silica.

[0040] S3: Add 6g hexadecyltrimethylammonium bromide, 3.5g urea, 60g expanded graphite composite silica and 1.8L deionized water to a reaction vessel and stir for 40min at 25℃ and 600r / min. Then add 170mL cyclohexane, 48mL isopropanol and 12mL tetraethyl orthosilicate and continue stirring for 40min. Heat to 74℃ and continue stirring for 18h. Filter and wash the precipitate four times with deionized water and anhydrous ethanol. Dry under vacuum at 70℃ for 2h to obtain expanded graphite composite brush-like silica.

[0041] S4: Add 40 mL of deionized water, 340 mL of anhydrous ethanol and 40 mL of γ-aminopropyltriethoxysilane to the reaction vessel and stir for 50 min at 25 °C and 600 r / min to obtain a mixed solution; add 40 g of expanded graphite composite brush-shaped silica, 25 mL of deionized water and 70 mL of anhydrous ethanol to the reaction vessel and stir for 14 min at 25 °C and 600 r / min, then add 320 mL of the mixed solution and continue stirring for 3 h. After the reaction is completed, vacuum filter the product using a circulating water multi-purpose vacuum pump, wash the filter cake four times with deionized water and anhydrous ethanol, and vacuum dry at 70 °C for 2 h to obtain the expanded dispersion packing.

[0042] S5: Mix 90g of nitrile rubber and 70g of chloroprene rubber, and then plasticize at 45℃ and 50r / min for 17min to obtain plasticized rubber; mix 150g of plasticized rubber, 20g of expanded dispersion filler, 4g of antioxidant RD, 3g of stearic acid, 9g of plasticizer dibutyl phthalate, 5g of zinc oxide, 4g of dicumyl peroxide and 3g of accelerator M for 5min, put it into a mold, and vulcanize at 150℃ for 15min to obtain a high-strength aging-resistant rubber sealing ring.

[0043] Comparative Example 1: Based on Example 3, the expanded graphite in step S2 was replaced with the natural flake graphite in step S1.

[0044] Comparative Example 2: Based on Example 3, the expanded graphite composite brush-shaped silica in step S4 was replaced with the expanded graphite composite silica prepared in step S2.

[0045] Comparative Example 3: Based on Example 3, the expanded dispersion filler in step S5 was replaced with the expanded graphite composite brush-shaped silica prepared in step S3.

[0046] The high-strength, aging-resistant rubber sealing rings prepared in Examples 1-3 and Comparative Examples 1-3 were subjected to performance tests. Tensile strength was tested according to the method specified in GB / T528-2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber". The samples were then heat-treated at 150℃ and 70% relative humidity for 80 hours, and the tensile strength was tested again according to the method specified in GB / T528-2009 "Determination of Tensile Stress-Strain Properties of Vulcanized Rubber or Thermoplastic Rubber". The test specimens were type 1A dumbbell-shaped specimens, and the tensile rate was 500 mm / min. The oil used was liquid B (30% toluene, 70% isooctane) according to GB / T1690-2010 standard, and the mass change rate was tested at 23℃ for 168 hours. The tensile elongation was determined according to ASTM D412. The results are shown in Table 1. Table 1

[0047] As can be seen from Table 1, Comparative Example 1, which replaced expanded graphite with natural flake graphite in step S1, lacked intercalation modification. Natural flake graphite has strong interlayer forces and small interlayer spacing, and cannot form an expansion function. It cannot fill rubber cracks or compensate for thermal shrinkage at high temperatures. Aging factors can easily penetrate, resulting in a significant decrease in heat resistance and damp heat aging performance. Without composite silica, it has no physical barrier effect and cannot form a core-shell structure. Its stress dispersion ability is extremely poor, and its mechanical strength and performance retention rate after aging are the lowest.

[0048] Comparative Example 2 replaced expanded graphite composite brush-shaped silica with expanded graphite composite silica. Lacking the brush-shaped silica structure, it was only ordinary composite silica. It could not strengthen the interface bonding with the rubber matrix through brush-shaped interpenetration, resulting in insufficient stress dispersion ability. Without the directional growth modification of step S3, the silica layer structure was loose, and the barrier effect against aging factors was weaker than that of the brush-shaped structure. Moreover, there was no interface optimization effect of extrusion and interpenetration at high temperature, and the performance loss after thermal aging and damp heat aging was more obvious.

[0049] Comparative Example 3 replaced the expanded dispersing filler with expanded graphite composite brush-shaped silica. Lacking γ-aminopropyltriethoxysilane modification, the hydroxyl groups on the surface of the brush-shaped silica did not form chemical bonds with the silane coupling agent, resulting in insufficient compatibility with the rubber matrix, slightly poor dispersion uniformity, and a tendency to local agglomerate. Without the bridging effect of the silane coupling agent, the bonding between the filler and the matrix could not be strengthened through chemical bonds at high temperatures, the stress release effect was weakened, and the performance retention rate after thermal aging was low.

[0050] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. A method for preparing a high-strength, aging-resistant rubber sealing ring, characterized in that, Includes the following steps: Step 1: Natural flake graphite was intercalated using potassium permanganate as an oxidant and perchloric acid and ammonium nitrate as intercalating agents to obtain expanded graphite; expanded graphite composite silica was prepared by depositing silica nanorods on the surface of expanded graphite using hexadecyltrimethylammonium bromide as a template agent and tetraethyl orthosilicate as a silicon source via sol-gel method. Step 2: Using silica nanorods on the surface of expanded graphite composite silica as growth sites, silica is again directionally grown into a brush-like nanostructure through the sol-gel method to obtain expanded graphite composite brush-like silica. Step 3: γ-aminopropyltriethoxysilane is first hydrolyzed in a water and ethanol system and then chemically bonded to the hydroxyl groups of expanded graphite composite brush-shaped silica to obtain an expanded dispersion filler. Step 4: Mix nitrile rubber and chloroprene rubber at a mass ratio of 80-90:60-70 and then plasticize for 15-17 minutes to obtain plasticized rubber; mix the plasticized rubber, expanded dispersion filler, antioxidant RD, stearic acid, dibutyl phthalate, zinc oxide, dicumyl peroxide and accelerator M for 4-5 minutes, put it into a mold and vulcanize to obtain a high-strength aging-resistant rubber sealing ring; The ratio of the following components is: plasticized rubber, expanded dispersion filler, antioxidant RD, stearic acid, dibutyl phthalate, zinc oxide, dicumyl peroxide and accelerator Md. The specific preparation steps of the expanded dispersion packing are as follows: Expanded graphite composite brush-shaped silica, deionized water and anhydrous ethanol were added to a reaction vessel and stirred for 12-14 min at 20-25℃ and 500-600 r / min. Then, a mixed solution was added and stirring was continued for 2-3 h. After the reaction was completed, the product was vacuum filtered using a circulating water multi-purpose vacuum pump. The filter cake was washed 2-4 times with deionized water and anhydrous ethanol and vacuum dried at 60-70℃ for 1-2 h to obtain the expanded dispersion packing. The specific steps for preparing the mixed solution are as follows: Deionized water, anhydrous ethanol and γ-aminopropyltriethoxysilane were added to a reaction vessel and stirred for 40-50 minutes at 20-25℃ and 500-600 r / min to obtain a mixed solution. The ratio of deionized water, anhydrous ethanol, and γ-aminopropyltriethoxysilane is 30-40 mL: 300-340 mL: 30-40 mL.

2. The method for preparing a high-strength, aging-resistant rubber sealing ring according to claim 1, characterized in that, The specific preparation steps for the expanded graphite are as follows: Natural flake graphite, potassium permanganate, perchloric acid, and ammonium nitrate were added to a reaction vessel at a mass ratio of 1:0.42-0.45:7-8:0.10-0.

12. The mixture was stirred for 15-20 minutes at 20-25℃ and 500-600 rpm. After filtration, the precipitate was washed 2-4 times with deionized water until the pH value was 6.0-6.

17. The precipitate was then vacuum dried at 60-70℃ for 4-5 hours to obtain expanded graphite.

3. The method for preparing a high-strength, aging-resistant rubber sealing ring according to claim 1, characterized in that, The specific preparation steps for the expanded graphite composite silica are as follows: Expanded graphite, hexadecyltrimethylammonium bromide, and ammonia were added to a reaction vessel and stirred for 30-40 minutes at 20-25°C and 500-600 rpm. Then, tetraethyl orthosilicate was added, and the reaction was continued for 6-7 hours. The mixture was centrifuged at 8000-8200 rpm for 5-8 minutes, heated to 80-82°C, and then isopropanol and ammonium nitrate were added. The mixture was stirred for 24-26 hours to remove the template agent. The mixture was then freeze-dried under vacuum at -20°C for 12-14 hours to obtain expanded graphite composite silica.

4. The method for preparing a high-strength, aging-resistant rubber sealing ring according to claim 3, characterized in that, The ratio of expanded graphite, hexadecyltrimethylammonium bromide, ammonia, tetraethyl orthosilicate, isopropanol, and ammonium nitrate is 70-75g: 5.6-5.8g: 1.4-1.5L: 24-26mL: 500-600mL: 3-4g.

5. The method for preparing a high-strength, aging-resistant rubber sealing ring according to claim 1, characterized in that, The specific preparation steps for the expanded graphite composite brush-shaped silica are as follows: Hexadecyltrimethylammonium bromide, urea, expanded graphite composite silica, and deionized water were added to a reaction vessel and stirred for 30-40 min at 20-25℃ and 500-600 r / min. Then, cyclohexane, isopropanol, and tetraethyl orthosilicate were added, and stirring was continued for another 30-40 min. The mixture was then heated to 70-74℃ and stirred for 16-18 h. After filtration, the precipitate was washed 2-4 times with deionized water and anhydrous ethanol and dried under vacuum at 60-70℃ for 1-2 h to obtain expanded graphite composite brush-like silica.

6. The method for preparing a high-strength, aging-resistant rubber sealing ring according to claim 5, characterized in that, The ratio of hexadecyltrimethylammonium bromide, urea, expanded graphite composite silica, deionized water, cyclohexane, isopropanol and tetraethyl orthosilicate is 5-6g: 3-3.5g: 50-60g: 1.5-1.8L: 150-170mL: 46-48mL: 10-12mL.

7. The method for preparing a high-strength, aging-resistant rubber sealing ring according to claim 1, characterized in that, The ratio of expanded graphite composite brush-shaped silica, deionized water, anhydrous ethanol, and the mixed solution is 30-40g: 20-25mL: 60-70mL: 300-320mL.

8. A high-strength, aging-resistant rubber sealing ring, characterized in that, It is prepared by the preparation method described in any one of claims 1-7.

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