A hydrogenated nitrile butadiene rubber article for low temperature oil resistant seal and a method for preparing the same

Abstract

The application discloses a hydrogenated nitrile rubber product for low-temperature oil-proof seal and a preparation method thereof, and belongs to the technical field of rubber materials. The method comprises the following steps: hydrogenation reaction of nitrile rubber, ene sulfide hydrogenation aid, ruthenium catalyst and solvent under the conditions of 2.0-6.0 MPa of hydrogen pressure and 40-80 DEG C for 6-12 hours, removal of the solvent under negative pressure to obtain modified hydrogenated nitrile rubber; and mixing of the modified hydrogenated nitrile rubber with carbon black, reinforcing agent, plasticizer, zinc oxide, antioxidant, sulfur, vulcanization accelerator, stearic acid, vulcanization and forming to obtain the hydrogenated nitrile rubber product. The specific ene sulfide hydrogenation aid and ruthenium catalyst are introduced in the hydrogenation modification stage, the flexibility and oil resistance of the nitrile rubber are improved from the source, the prepared rubber product still has good mechanical properties and sealing performance in the extreme environment such as low temperature and oil immersion, and is suitable for low-temperature oil-proof seals in the fields of aerospace, automobile, oil field drilling and the like.

Description

Technical Field

[0001] This invention belongs to the field of rubber material technology, specifically relating to a hydrogenated nitrile butadiene rubber product for low-temperature oil-proof seals and its preparation method. Background Technology

[0002] Hydrogenated nitrile butadiene rubber (HNBR) is a highly saturated nitrile elastomer produced by selectively hydrogenating the butadiene units in nitrile butadiene rubber (NBR). It possesses excellent high-temperature resistance, aging resistance, chemical stability, and superior oil and media resistance, making it widely used in aerospace, military equipment, automotive, oilfield drilling, petrochemical, electronics, textile printing, and other fields. It is commonly used in automotive oil seals, fuel system components, drive belts, drilling housings and mud pistons, printing and textile rollers, aerospace seals, and vibration damping materials. In the high-temperature, high-pressure environment of oil and gas wells, fluororubber or nitrile butadiene rubber is easily corroded and rapidly damaged by media such as hydrochloric acid, hydrogen sulfide, and carbon dioxide, while hydrogenated nitrile butadiene rubber can be used stably and continuously, exhibiting superior overall performance. In the automotive industry, oil hoses require excellent gasoline resistance, and drive belts require stable hardness, modulus, dynamic performance, and oil resistance over a wide temperature range; hydrogenated nitrile butadiene rubber again outperforms nitrile butadiene rubber and chloroprene rubber in this regard. Furthermore, this material also has good applications in automotive lubrication system parts and radiation-resistant nuclear power plant components.

[0003] In special environments, rubber seals must withstand harsh working conditions. High and low temperature changes and mechanical stress during use can lead to aging and even failure of the seals. Especially in low-temperature environments, rubber hardens, its mechanical properties decrease, and it is prone to cracking under repeated mechanical stress. CN118206810B improves the rubber formulation to enable hydrogenated nitrile rubber to withstand low-temperature use without cracking, but the addition of a large amount of ethylene-acrylate rubber significantly reduces the oil resistance of the resulting seals, making oil leakage difficult to prevent. CN121517785A enhances the oil resistance and low-temperature resistance of hydrogenated nitrile rubber seals by adding modified end-thiol polyethers and high-vinyl polybutadiene rubber to the rubber formulation. This significantly reduces the low-temperature brittleness temperature and provides excellent compression set resistance and oil resistance. However, the synthesis of modified end-thiol polyethers is complex and requires the introduction of fluorinated molecular chains, resulting in high costs and significantly limiting the widespread application of this technology. Summary of the Invention

[0004] To address the shortcomings of the existing technology, this invention provides a hydrogenated nitrile butadiene rubber product for low-temperature oil-resistant seals and its preparation method. By introducing specific olefinic sulfide hydrogenation aids and ruthenium catalysts during the hydrogenation modification stage, the flexibility and oil resistance of nitrile butadiene rubber are improved from the source, thereby solving the technical problem that it is difficult to achieve both low-temperature resistance and oil resistance of hydrogenated nitrile butadiene rubber. This provides a solution for sealing rubber parts to have both oil resistance and good sealing performance under extreme conditions such as high and low temperatures.

[0005] The present invention provides a method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals, comprising the following steps:

[0006] Step 1: Mix tris(triphenylphosphine) dichloride, ammonium iron sulfate, triethylamine, tetrafluoroborate ether solution and solvent A evenly, and age at 40-80℃ for 1-8 hours under a normal pressure nitrogen atmosphere to obtain a ruthenium catalyst.

[0007] Step 2: Add nitrile rubber, alkene sulfide hydrogenation aid, the ruthenium catalyst and solvent B into the reactor, introduce hydrogen gas and maintain the gauge pressure at 2.0-6.0 MPa, and carry out the hydrogenation reaction at 40-80°C for 6-12 hours. After the reaction is complete, remove the solvent under negative pressure to obtain modified hydrogenated nitrile rubber.

[0008] The chemical structure of the olefin sulfide hydrogenation aid is shown in the following formula:

[0009]

[0010] In the formula, R1 represents hydrogen, C1 to C2. 12 Alkyl, C1-C 12 Any one of alkylthio, aryl, or arylthio, where R2 represents C1 to C2. 12 Alkyl, aryl, C2-C 12 Any of the alkenyl groups.

[0011] Step 3: Mix 100 parts of the modified hydrogenated nitrile rubber with 50-60 parts of carbon black, 10-20 parts of reinforcing agent, 5-10 parts of plasticizer, 5-10 parts of zinc oxide, 1-2 parts of antioxidant, 0.5-1 part of sulfur, 1-5 parts of vulcanization accelerator, and 1-2 parts of stearic acid according to the mass ratio, and then vulcanize and mold to obtain the hydrogenated nitrile rubber product.

[0012] Preferably, in step 1, the tetrafluoroborate ether solution is a tetrafluoroborate ether solution, and the mass fraction of tetrafluoroborate in the tetrafluoroborate ether solution is 48%; the mass ratio of ammonium iron sulfate, triethylamine, tetrafluoroborate ether, and tris(triphenylphosphine) ruthenium chloride is 2:10:1.5:1; and the mass fraction of tris(triphenylphosphine) ruthenium chloride in solvent A is 1‰ to 5‰.

[0013] Preferably, in step 2, the mass fraction of the nitrile rubber in solvent B is 4% to 8%; the nitrile rubber is any one of the following: low-nitrile nitrile rubber with an acrylonitrile content of 16% to 24%, medium-nitrile nitrile rubber with an acrylonitrile content of 25% to 30%, medium-high-nitrile nitrile rubber with an acrylonitrile content of 31% to 35%, and high-nitrile nitrile rubber with an acrylonitrile content of 36% to 42%.

[0014] Preferably, in step 2, the amount of ruthenium catalyst added is 5% to 10% of the mass of the nitrile rubber.

[0015] Preferably, in step 2, R1 represents any one of hydrogen, C1-C6 alkyl, phenyl, and phenylthio, and R2 represents any one of C1-C6 alkyl, phenyl, and C2-C6 alkenyl.

[0016] Preferably, in step 2, the amount of the olefin sulfide hydrogenation aid added is 0.5‰ to 5‰ of the mass of the nitrile rubber.

[0017] Preferably, in step 1, solvent A is any one of butanone, acetone, toluene, xylene, chlorobenzene, dichlorobenzene, and trichlorobenzene. In step 2, solvent B is the same as solvent A in step 1.

[0018] Preferably, in step 3, the reinforcing agent is any one or more of silica, sulphuric acid, and kaolin; the plasticizer is tri(2-ethylhexyl)trimethicone (TOTM) or di[2-(2-butoxyethoxy)ethyl adipic acid (TP-95); the antioxidant is any one or more of 2-thiol-benzimidazole zinc salt (ZMB), 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine (SOV445), 2,2,4-trimethyl-1,2-dihydroquinoline polymer (RD), and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (4020); and the vulcanization accelerator is any one or more of tetramethylthiuram disulfide (TMTD), N-cyclohexyl-2-benzothiazole sulfenamide (CZ), and dibenzothiazole disulfide (DM).

[0019] Preferably, in step 3, the mixing is carried out on a two-roll open mill at a roll temperature of 45–55°C; the vulcanization molding is carried out in a flat vulcanizer at 170–190°C for 5–15 minutes.

[0020] The present invention also provides a hydrogenated nitrile rubber product for low-temperature oil-proof seals, which is prepared by the above-described method.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] 1. This invention modifies the flexibility and oleophobicity of nitrile rubber polymers from the source by introducing specific olefinic sulfide hydrogenation auxiliaries and ruthenium catalysts during the hydrogenation modification stage of nitrile rubber. This solves the problem that hydrogenated nitrile rubber cannot simultaneously achieve good oil resistance and low-temperature resistance. Even using conventional mixing formulations and vulcanization processes, low-temperature resistant and oil-proof sealing components can be obtained without the need for cumbersome additive processes or complex formulation designs, overcoming the "treating the symptoms but not the root cause" shortcomings of existing technologies.

[0023] 2. The rubber products obtained by this invention exhibit excellent mechanical properties and oil resistance under extreme environmental conditions, and maintain good sealing performance even when used in low-temperature media. Rubber seals made from medium-high nitrile modified hydrogenated nitrile rubber can achieve a low-temperature brittleness temperature of -40℃, which is approximately 10℃ lower than that of seals made from unmodified ordinary nitrile rubber. Simultaneously, their oil resistance is significantly improved, meeting the requirements for sealing rubber components under extreme conditions such as high and low temperatures.

[0024] 3. The hydrogenation modification method of the present invention is effective for nitrile rubber raw materials with different acrylonitrile contents (low acrylonitrile type, medium acrylonitrile type, medium-high acrylonitrile type, and high acrylonitrile type), has wide applicability, is easy to promote in industrial production, and can significantly improve production efficiency. Attached Figure Description

[0025] Figure 1 These are rubber parts made by mixing and vulcanizing modified hydrogenated nitrile butadiene rubber according to a certain formula and then molding them in different molds. Detailed Implementation

[0026] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited to these embodiments.

[0027] Example 1

[0028] The method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals provided in this embodiment includes:

[0029] Step 1: Mix 0.4g of tris(triphenylphosphine) dichloride, 0.8g of ammonium iron sulfate, 4g of triethylamine, 0.6g of tetrafluoroborate ether solution with a mass fraction of 48%, and 399.6g of butanone evenly. The resulting mixture is aged at 60°C for 2 hours under a nitrogen atmosphere at normal pressure to obtain the ruthenium catalyst.

[0030] Step 2: Mix 3 kg of medium-high acrylonitrile rubber (grade NBR3304G) with 57 kg of methyl ethyl ketone (MEK) evenly and add it to a batch reactor. Add 1.5 g of ethyl vinyl sulfide and 300 g of ruthenium catalyst. Introduce hydrogen into the batch reactor and maintain the gauge pressure at 4.0 MPa. Perform hydrogenation reaction at 60°C for 6 h. After the reaction is complete, evaporate the MEK at 60°C under a vacuum of 10 mmHg to remove the MEK, and obtain modified hydrogenated nitrile rubber.

[0031] Step 3: Weigh 200g of modified hydrogenated nitrile butadiene rubber, 100g of carbon black, 40g of clay, 20g of plasticizer TP-95, 10g of zinc oxide, 3g of antioxidant SOV445, 2g of sulfur, 2g of vulcanization accelerator CZ, 2g of vulcanization accelerator TMTD, and 3g of stearic acid. Mix these ingredients on a two-roll mill at a roll temperature of 50℃. The mixing process is as follows: First, pass the modified hydrogenated nitrile butadiene rubber through the mill in a thin pass, then wrap it around the front roll to form a rubber mass between the rolls. Next, add carbon black, clay, plasticizer, zinc oxide, antioxidant, stearic acid, vulcanization accelerator, and sulfur in sequence. After the material has been fully fed, pass it through the two-roll mill in a thin pass, pack it six times, and then sheet it to obtain the compound. The obtained rubber compound is placed into the required mold according to the testing requirements or application scenario. The mold is then placed in a flat vulcanizing apparatus and vulcanized at 180°C for 10 minutes to obtain hydrogenated nitrile rubber products (such as...). Figure 1 (As shown).

[0032] Example 2

[0033] In step 2 of this embodiment, 4 kg of low-acrylonitrile nitrile rubber (grade NBR2306) with an acrylonitrile content of 21.5% was mixed evenly with 46 kg of butanone and then added to a batch reactor. 20 g of phenyl vinyl sulfide and 400 g of ruthenium catalyst were also added. Hydrogen gas was introduced into the batch reactor and the gauge pressure was maintained at 4.0 MPa. The hydrogenation reaction was carried out at 60°C for 6 hours. After the reaction was complete, the butanone was evaporated at 60°C under a vacuum of 10 mmHg to remove it, yielding modified hydrogenated nitrile rubber. The other steps were the same as in Example 1, resulting in a hydrogenated nitrile rubber product.

[0034] Example 3

[0035] In step 2 of this embodiment, 3 kg of acrylonitrile-type nitrile rubber (grade NBR2808) with an acrylonitrile content of 28.6% was mixed evenly with 47 kg of butanone and then added to a batch reactor. 12 g of 1,2-bis(phenylmercapto)ethylene and 300 g of ruthenium catalyst were added. Hydrogen gas was introduced into the batch reactor and the gauge pressure was maintained at 4.0 MPa. The hydrogenation reaction was carried out at 60°C for 6 hours. After the reaction was complete, the butanone was evaporated at 60°C under a vacuum of 10 mmHg to remove it, yielding modified hydrogenated nitrile rubber. The other steps were the same as in Example 1, resulting in a hydrogenated nitrile rubber product.

[0036] Example 4

[0037] In step 2 of this embodiment, 3 kg of high-acrylonitrile nitrile rubber (grade NBR4105) with an acrylonitrile content of 41.0% was mixed evenly with 57 kg of butanone and then added to a batch reactor. 6 g of divinyl sulfide and 300 g of ruthenium catalyst were also added. Hydrogen gas was introduced into the batch reactor and the gauge pressure was maintained at 4.0 MPa. The hydrogenation reaction was carried out at 60°C for 6 hours. After the reaction was complete, the butanone was evaporated at 60°C under a vacuum of 10 mmHg to remove it, yielding modified hydrogenated nitrile rubber. The other steps were the same as in Example 1, resulting in a hydrogenated nitrile rubber product.

[0038] Example 5

[0039] In step 1 of this embodiment, methyl ethyl ketone (MEK) is replaced with an equal volume of acetone. In step 2, 3 kg of medium-high acrylonitrile-type nitrile rubber (grade NBR3304G) with an acrylonitrile content of 33.6% is mixed evenly with 57 kg of acetone and added to a batch reactor. 3 g of ethyl vinyl sulfide and 150 g of ruthenium catalyst are also added. Hydrogen gas is introduced into the batch reactor and the gauge pressure is maintained at 6.0 MPa. The hydrogenation reaction is carried out at 50°C for 6 hours. After the reaction is complete, the acetone is evaporated at 60°C under a vacuum of 10 mmHg to remove the acetone, yielding modified hydrogenated nitrile rubber. The other steps are the same as in Example 1, resulting in a hydrogenated nitrile rubber product.

[0040] Example 6

[0041] In step 1 of this embodiment, methyl ethyl ketone (MEK) is replaced with an equal volume of toluene. In step 2, 4 kg of medium-high acrylonitrile-type nitrile rubber (grade NBR3304G) with an acrylonitrile content of 33.6% is mixed evenly with 46 kg of toluene and added to a batch reactor. 6 g of ethyl vinyl sulfide and 320 g of ruthenium catalyst are also added. Hydrogen gas is introduced into the batch reactor and the gauge pressure is maintained at 5.0 MPa. The hydrogenation reaction is carried out at 40°C for 6 hours. After the reaction is complete, toluene is evaporated at 70°C under a vacuum of 10 mmHg to remove the toluene, yielding modified hydrogenated nitrile rubber. The other steps are the same as in Example 1, resulting in a hydrogenated nitrile rubber product.

[0042] Comparative Example 1

[0043] The difference between this comparative example and Example 1 is that ethyl vinyl sulfide is not added in step 2.

[0044] Comparative Example 2

[0045] The difference between this comparative example and Example 2 is that phenyl vinyl sulfide is not added in step 2.

[0046] Comparative Example 3

[0047] The difference between this comparative example and Example 3 is that 1,2-bis(phenylmercapto)ethylene is not added in step 2.

[0048] Comparative Example 4

[0049] The difference between this comparative example and Example 4 is that divinyl sulfide is not added in step 2.

[0050] Comparative Example 5

[0051] Hydrogenated nitrile butadiene rubber products were prepared directly using hydrogenated nitrile butadiene rubber (brand name Therban3406) with an acrylonitrile content of 34% according to step 3 of Example 1.

[0052] Comparative Example 6

[0053] Hydrogenated nitrile butadiene rubber products were prepared directly using hydrogenated nitrile butadiene rubber (brand name TherbanLT2007) with an acrylonitrile content of 21% according to step 3 of Example 1.

[0054] The modified hydrogenated nitrile butadiene rubber obtained in Examples 1-6 above was tested for hydrogenation degree (according to the method specified in standard SH / T 1762-2008 "Determination of Residual Unsaturation of Hydrogenated Nitrile Butadiene Rubber (HNBR) by Infrared Spectroscopy"). Simultaneously, the hydrogenated nitrile butadiene rubber products obtained in Examples 1-6 and Comparative Examples 1-6 were tested for low-temperature brittleness temperature (referring to the test method in GB / T 15256-2014 test standard) and oil resistance (referring to GB / T1690-2010, the samples were immersed in IRM901# oil at 150℃ for 72h, and the changes in hardness, tensile strength, and elongation at break before and after immersion were detected). The test results are shown in Table 1.

[0055] Table 1

[0056]

[0057] As shown in Table 1, this invention, by adding an alkenyl sulfide hydrogenation auxiliary agent to the nitrile rubber hydrogenation system, without affecting the degree of hydrogenation, allows the alkenyl sulfide hydrogenation auxiliary agent to interact with the ruthenium catalyst, making the molecular chain arrangement of nitrile rubber more random during hydrogenation. This significantly disrupts the microcrystalline region of the cis-butene molecular structure and makes the oleophobic cyano groups more prominent, thus significantly improving the low-temperature resistance and oil resistance of the rubber seals. Comparison of Examples 1-4 with Comparative Examples 1-4 shows that the method of this invention effectively improves the performance of the resulting rubber seals by hydrogenating nitrile rubber raw materials with different acrylonitrile contents (from low-nitrile to high-nitrile). The low-temperature brittleness temperature of the rubber seals made from medium-high acrylonitrile modified hydrogenated nitrile rubber can reach -40℃, which is about 10℃ lower than that of the unmodified nitrile rubber raw material seals, and the oil resistance is also improved simultaneously, indicating that the method of this invention has good applicability to nitrile rubber raw materials with different acrylonitrile contents. Comparative Examples 5-6 and 6 show that, under conditions where the degree of hydrogenation reaches 95% or higher, changes in the amount of ruthenium catalyst and hydrogenation reaction conditions (including hydrogen pressure, reaction temperature, and reaction time) have little impact on the low-temperature resistance and oil resistance of the resulting rubber seals. This indicates that, after meeting the basic hydrogenation requirements, the low-temperature performance and oil resistance of the final product of the modified hydrogenated nitrile butadiene rubber prepared by the method of this invention mainly depend on the hydrogenation modification itself, rather than the fluctuations in specific operating parameters during the hydrogenation process. Furthermore, compared to commercially available hydrogenated nitrile butadiene rubber, the modified hydrogenated nitrile butadiene rubber of this invention improves its mechanical properties at low temperatures while ensuring the oil resistance of the final rubber parts, fundamentally solving the drawbacks of commercially available hydrogenated nitrile butadiene rubber requiring the addition of additives or complex formulation design during processing.

[0058] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Any simple modifications, alterations, or equivalent structural changes made to the above embodiments based on the technical essence of the invention shall still fall within the protection scope of the present invention.

Claims

1. A method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals, characterized in that, Includes the following steps: Step 1: Mix tris(triphenylphosphine) ruthenium dichloride, ammonium iron sulfate, triethylamine, tetrafluoroborate ether solution and solvent A evenly, and age at 40-80℃ for 1-8 hours under a normal pressure nitrogen atmosphere to obtain ruthenium catalyst; Step 2: Add nitrile rubber, alkene sulfide hydrogenation aid, the ruthenium catalyst and solvent B into the reactor, introduce hydrogen gas and maintain the gauge pressure at 2.0-6.0 MPa, and carry out the hydrogenation reaction at 40-80°C for 6-12 hours. After the reaction is completed, remove the solvent under negative pressure to obtain modified hydrogenated nitrile rubber. The chemical structure of the olefin sulfide hydrogenation aid is shown in the following formula: In the formula, R1 represents hydrogen, C1 to C2. 12 Alkyl, C1-C 12 Any one of alkylthio, aryl, or arylthio, where R2 represents C1 to C2. 12 Alkyl, aryl, C2-C 12 Any one of the alkenyl groups; Step 3: Mix 100 parts of the modified hydrogenated nitrile rubber with 50-60 parts of carbon black, 10-20 parts of reinforcing agent, 5-10 parts of plasticizer, 5-10 parts of zinc oxide, 1-2 parts of antioxidant, 0.5-1 part of sulfur, 1-5 parts of vulcanization accelerator, and 1-2 parts of stearic acid according to the mass ratio, and then vulcanize and mold to obtain the hydrogenated nitrile rubber product.

2. The method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals according to claim 1, characterized in that, In step 1, the mass fraction of tetrafluoroboric acid in the tetrafluoroboric acid ether solution is 48%; the mass ratio of ammonium iron sulfate, triethylamine, tetrafluoroboric acid ether and tris(triphenylphosphine) ruthenium chloride is 2:10:1.5:1; and the mass fraction of tris(triphenylphosphine) ruthenium chloride in solvent A is 1‰ to 5‰.

3. The method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals according to claim 1, characterized in that, In step 2, the mass fraction of the nitrile rubber in solvent B is 4% to 8%; the nitrile rubber is any one of the following: low-nitrile nitrile rubber with an acrylonitrile content of 16% to 24%, medium-nitrile nitrile rubber with an acrylonitrile content of 25% to 30%, medium-high-nitrile nitrile rubber with an acrylonitrile content of 31% to 35%, and high-nitrile nitrile rubber with an acrylonitrile content of 36% to 42%.

4. The method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals according to claim 1, characterized in that, In step 2, the amount of ruthenium catalyst added is 5% to 10% of the mass of the nitrile rubber.

5. The method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals according to claim 1, characterized in that, In step 2, R1 represents any one of hydrogen, C1-C6 alkyl, phenyl, and phenylthio, and R2 represents any one of C1-C6 alkyl, phenyl, and C2-C6 alkenyl.

6. The method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals according to claim 1, characterized in that, In step 2, the amount of the olefin sulfide hydrogenation aid added is 0.5‰ to 5‰ of the mass of the nitrile rubber.

7. The method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals according to claim 1, characterized in that, In step 1, solvent A is any one of butanone, acetone, toluene, xylene, chlorobenzene, dichlorobenzene, and trichlorobenzene; in step 2, solvent B is the same as solvent A in step 1.

8. The method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals according to claim 1, characterized in that, In step 3, the reinforcing agent is any one or more of silica, sulphuric acid, and kaolin; the plasticizer is tri(2-ethylhexyl) trimellitate or di[2-(2-butoxyethoxy)ethyl adipic acid; the antioxidant is any one or more of 2-thiol-benzimidazole zinc salt, 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine, 2,2,4-trimethyl-1,2-dihydroquinoline polymer, and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine; and the vulcanization accelerator is any one or more of tetramethylthiuram disulfide, N-cyclohexyl-2-benzothiazole sulfenamide, and dibenzothiazole disulfide.

9. The method for preparing hydrogenated nitrile butadiene rubber products for low-temperature oil-proof seals according to claim 1, characterized in that, In step 3, the mixing is carried out on a two-roll mill at a roll temperature of 45–55°C; the vulcanization molding is carried out in a flat vulcanizer at 170–190°C for 5–15 minutes.

10. A hydrogenated nitrile rubber product for use in low-temperature oil-resistant seals, characterized in that: It is prepared by the preparation method according to any one of claims 1 to 9.

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