NBR oil seal for automobile engine system and preparation method of NBR oil seal

Abstract

The invention relates to the technical field of automobile oil seal materials, and particularly discloses an NBR oil seal for an automobile engine system and a preparation method of the NBR oil seal. The invention discloses an NBR oil seal for an automobile engine system. The NBR oil seal comprises the following components in parts by weight: 100 parts of NBR rubber, 80-115 parts of carbon black, 10-15 parts of a TP759 heat-resistant plasticizer, 5-7 parts of zinc oxide, 0.5-1.5 parts of stearic acid, 3-6 parts of an anti-aging agent, 1-2 parts of protective wax, 0.1-0.5 part of sulfur and 1.5-3 parts of an accelerant. The NBR oil seal material prepared by the technical scheme of the invention has better heat resistance and lower compression deformation.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of automobile oil seal materials, in particular to an NBR oil seal for an automobile engine system and a preparation method thereof. BACKGROUND

[0002] At present, the automobile oil seal is one of the very important parts of automobile components, and its main function is to ensure that the transmission parts of the automobile are isolated from the lubricating oil and are not penetrated, and external impurities can also be prevented from entering the internal mechanical parts. With the continuous development of the automobile industry, various new materials, technologies and requirements are constantly emerging, resulting in higher requirements for sealing standards. Under working conditions, the oil seal and the transmission parts rotate relative to each other, resulting in an increase in temperature, and not only the oil resistance needs to be considered, but also the temperature resistance needs to be considered.

[0003] Among them, nitrile rubber (NBR) is widely used in oil seal products due to its excellent oil resistance, processability and cost performance. The existing nitrile rubber can be used in air medium below 100 DEG C for a long time, but when used in an environment of about 120 DEG C, the compression permanent deformation performance becomes poor after 70 hours, the hardness changes and the elongation changes are large, and the long-term use risk is high.

[0004] Therefore, it is of great significance to develop a mixing rubber with good heat resistance and pressure change for automobile oil seals. SUMMARY

[0005] In order to solve the above technical problems, the application provides an NBR oil seal for an automobile engine system and a preparation method thereof.

[0006] The application provides an NBR oil seal for an automobile engine system, which specifically comprises the following components by weight: 100 parts of NBR rubber, 80-115 parts of carbon black, 10-15 parts of TP759 heat-resistant plasticizer, 5-7 parts of zinc oxide, 0.5-1.5 parts of stearic acid, 3-6 parts of antioxidant, 1-2 parts of protective wax, 0.1-0.5 parts of sulfur, and 1.5-3 parts of accelerator. The NBR rubber is composed of NBR 3345 rubber and NBR 1965 rubber in a weight ratio of 65-75:25-35; The carbon black is prepared from semi-reinforcing carbon black N774, medium particle thermal cracking carbon black N990 and polyethylene glycol monomethyl ether in a weight ratio of 60-75:20-40:1-2; the molecular weight of the polyethylene glycol monomethyl ether is 1800-2200; The antioxidant is composed of quinoline antioxidant, p-phenylenediamine antioxidant and heterocyclic antioxidant in a weight ratio of 1-2:1-2:1-2; The accelerator is composed of a mixture of a sulfenamide accelerator CBS and a thiazole accelerator MBTS in a weight ratio of 1-2:0.5-1.

[0007] The component ratio principle of the technical scheme provided in the application is specifically: in the molecular structure of NBR rubber, NBR 3345 has a higher acrylonitrile content, a compact structure, is easy to generate more stable carbon-carbon bonds and single sulfur bonds, and is not easy to break or rearrange in the heat aging process; NBR 1965 has a relatively stable saturated main chain structure, and the vulcanization forms extremely stable carbon-carbon crosslinking bonds, which provides a very strong and stable skeleton for the crosslinking network under heat and pressure. The application improves the heat resistance of the entire molecular chain by using NBR 3345 rubber and NBR 1965 rubber as the main rubber and cooperating with the best ratio, and at the same time makes the NBR oil seal final product have a lower compression permanent deformation.

[0008] Carbon black N990 acts as an inert filling particle, reduces the overall crosslinking density, and reduces the oxidation reaction site; carbon black N774 provides moderate reinforcement and maintains basic mechanical properties, and its weak surface activity also reduces the interaction with rubber. The graft copolymerization technology is used to link polyethylene glycol to the surface of carbon black using polyethylene glycol monomethyl ether as a raw material to form a structural filler, which shields the catalytic degradation effect of the carbon black surface group on the rubber vulcanization network, and the chain segment can reversibly stretch / contract when stressed, which not only dissipates friction energy through molecular chain sliding, but also maintains the strength of the filler-matrix interface through entropy elasticity recovery, so that the elongation rate change and hardness change of the material after aging under high temperature conditions are kept at a low level; at the same time, polyethylene glycol can improve the dispersity of carbon black in the rubber matrix, uniform stress distribution and fewer local stress concentration points, which helps to improve the compression recovery performance.

[0009] For nitrile rubber, high-efficiency heat-resistant antioxidant must be selected, and the application uses quinoline antioxidant (2,2,4-trimethyl-1,2-dihydroquinoline antioxidant) in combination with heterocyclic antioxidant (2-mercaptobenzimidazole) and p-phenylenediamine antioxidant (N-isopropyl-N'-phenyl-p-phenylenediamine) to produce a synergistic effect, effectively capture free radicals generated in the process of thermal oxidation, terminate chain reactions, thereby delaying the crosslinking and degradation of high molecular chains, and increasing the protection effect.

[0010] The plasticizer has a great influence on heat resistance, and plasticizers with lower relative molecular mass are very easy to migrate, seep out or volatilize at high temperatures, resulting in increased hardness and reduced elongation of the vulcanized rubber, which gradually hardens the vulcanized rubber, so the application selects heat-resistant plasticizer TP759.

[0011] Different vulcanization systems form different cross-linking bonds, and the bond energies and oxygen absorption rates of various cross-linking bonds are different. The vulcanization system formed by sulfur, the sulfenamide type accelerator CBS and the thiazole type accelerator MBTS has good heat resistance and low compression deformation.

[0012] Preferably, the NBR oil seal for automobile engine systems specifically comprises the following components in parts by weight: NBR rubber 100 parts, carbon black 90-106 parts, TP759 heat-resistant plasticizer 11-14 parts, zinc oxide 5.5-6.5 parts, stearic acid 0.7-1.2 parts, antioxidant 4-5 parts, protective wax 1.2-1.8 parts, sulfur 0.2-0.4 parts, and accelerator 2-2.5 parts.

[0013] Preferably, the NBR rubber is composed of NBR 3345 rubber and NBR 1965 rubber in a weight ratio of 67-73:27-33.

[0014] Through experimental analysis, it can be known that the NBR oil seal material can further improve the performance by using the NBR 3345 rubber and the NBR 1965 rubber in the above weight ratio.

[0015] Preferably, the carbon black is prepared from semi-reinforcing carbon black N774, medium particle thermal cracking carbon black N990 and polyethylene glycol monomethyl ether in a weight ratio of 65-70:25-35:1.2-1.8.

[0016] In a specific embodiment, the carbon black is prepared from semi-reinforcing carbon black N774, medium particle thermal cracking carbon black N990 and polyethylene glycol monomethyl ether in a weight ratio of 68:30:1.5.

[0017] Preferably, in the preparation method of the carbon black, the molecular weight of the polyethylene glycol monomethyl ether is 2000.

[0018] Through experimental analysis, it can be known that the carbon black prepared from semi-reinforcing carbon black N774, medium particle thermal cracking carbon black N990 and polyethylene glycol monomethyl ether in the above weight ratio can further improve the performance of the NBR oil seal material.

[0019] Preferably, the preparation method of the carbon black is as follows: polyethylene glycol monomethyl ether is dissolved in toluene and dichlorosulfoxide, and reacted at 70-80℃ for 6-10h, and then activated polyethylene glycol monomethyl ether is obtained through rotary evaporation; Semi-reinforcing carbon black N774 and medium particle thermal cracking carbon black N990 are dispersed in anhydrous N,N-dimethylformamide, and then ultrasonic dispersion is performed, and then activated polyethylene glycol monomethyl ether and 4-dimethylaminopyridine are added, and the mixture is stirred and reacted at 80-100℃ for 24-48h under the protection of nitrogen; after the reaction is completed, the mixture is cooled to room temperature; and then the carbon black is obtained through washing and drying.

[0020] Preferably, in the preparation method of the carbon black, the weight ratio of toluene, dichlorosulfoxide and polyethylene glycol monomethyl ether is 8-12:15-25:1; the weight ratio of N,N-dimethylformamide and the total weight of raw materials is 1-5:1; the weight ratio of 4-dimethylaminopyridine and polyethylene glycol monomethyl ether is 0.005-0.02:1.

[0021] Preferably, the antioxidant is composed of quinoline antioxidants, p-phenylenediamine antioxidants and heterocyclic antioxidants with a weight ratio of 1-1.3:1.6-2:1-1.3.

[0022] Preferably, in the antioxidant, the quinoline antioxidant is 2,2,4-trimethyl-1,2-dihydroquinoline, the p-phenylenediamine antioxidant is N-isopropyl-N'-phenyl-p-phenylenediamine, and the heterocyclic antioxidant is 2-mercaptobenzimidazole.

[0023] Through experimental analysis, it can be known that the antioxidant composed of quinoline antioxidants, p-phenylenediamine antioxidants and heterocyclic antioxidants with the above weight ratio can further improve the performance of the NBR oil seal material.

[0024] Preferably, the accelerator is composed of secondary sulfonamide accelerator CBS and thiazole accelerator MBTS with a weight ratio of 1.5-2:0.5-0.7.

[0025] The application also provides a preparation method of the NBR oil seal for the automobile engine system, which specifically comprises the following steps in sequence: (1) Start the internal mixer, and add NBR rubber, zinc oxide, stearic acid, antioxidant and protective wax into the internal mixer, and mix at a speed of 35-45 r / min, with an upper plunger applying a pressure of 4-6 bar, for 60-80 s; (2) Add carbon black and TP759 heat-resistant plasticizer, and mix at a speed of 15-25 r / min and a pressure of 4-6 bar until the temperature reaches 130-140 DEG C, with intermediate pressure increase and exhaust 1-2 times; (3) After thinning, filtering and sheeting, cool and store for more than 8 h to obtain a masterbatch; (4) Add the masterbatch into the internal mixer, add sulfur and accelerator, and mix for 120-150 s, and discharge when the temperature is less than or equal to 100 DEG C; (5) After thinning and striping, cool to 20-25 DEG C, and store for 16-24 h to obtain a finished product.

[0026] In summary, the technical scheme of the application has the following effects: By using the technical scheme provided in the application, the NBR oil seal for an automobile engine system prepared has a compression permanent deformation of ≤16.8% at a test temperature of 120°C for 70 hours; and the elongation of the NBR oil seal product is ≥410%, and the hardness is 65-69; the elongation change rate after hot air aging can be controlled within-22%, and the hardness change can be controlled within 7. That is, the NBR oil seal material prepared by the technical scheme of the application has good heat resistance and low compression deformation. DETAILED DESCRIPTION

[0027] The application will be further described in detail below in combination with examples, comparative examples and performance test experiments, and these examples should not be understood as limiting the scope of the application.

[0028] Examples

[0029] Examples 1-5 Examples 1-5 respectively provide an NBR oil seal for an automobile engine system and a preparation method thereof.

[0030] The difference between the above examples is that the amount of each raw material component is different, as shown in Table 1.

[0031] The preparation method of the carbon black in the above examples is specifically as follows.

[0032] 1.5 g of polyethylene glycol monomethyl ether MPEG-2000 was dissolved in 15 g of toluene, 30 g of dichlorosulfoxide was added, and the reaction was carried out at 75°C for 7 h. After the reaction was completed, the excess solvent was removed by a rotary evaporator to obtain activated polyethylene glycol monomethyl ether; 68 g of semi-reinforcing carbon black N774 and 30 g of medium particle thermal cracking carbon black N990 were dispersed in 200 g of anhydrous N,N-dimethylformamide, and ultrasonic treatment was carried out for 30 min to fully disperse them. Then, the activated polyethylene glycol monomethyl ether and 0.02 g of 4-dimethylaminopyridine catalyst were added, and the reaction was carried out at 90°C for 36 h under nitrogen protection. After the reaction was completed, it was cooled to room temperature; washed by centrifugation with ethanol for 5 times, and dried at 80°C to obtain carbon black.

[0033] The preparation method of the NBR oil seal for an automobile engine system in the above examples is specifically as follows.

[0034] (1) Start the internal mixer, add NBR rubber (NBR rubber is composed of NBR 3345 rubber and NBR 1965 rubber in a weight ratio of 70:30), zinc oxide, stearic acid, antioxidant (composed of quinoline antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline, p-phenylenediamine antioxidant N-isopropyl-N'-phenyl-p-phenylenediamine, and heterocyclic antioxidant 2-mercaptobenzimidazole in a weight ratio of 1:2:1), and protective wax into the internal mixer, mix at a speed of 40 r / min, apply a pressure of 5 bar with the upper plunger, and mix for 70 s; (2) Add carbon black (prepared by mixing semi-reinforcing carbon black N774, medium particle thermal cracking carbon black N990, and polyethylene glycol monomethyl ether in a weight ratio of 68:30:1.5), and TP759 heat-resistant plasticizer, mix at a speed of 20 r / min and a pressure of 5 bar until the temperature reaches 135°C, and then increase the pressure twice to remove some small molecular organic substances; (3) Thin pass on the first open mill, filter in the rubber filter, and then sheet on the second open mill, and then cool and store for more than 8 h to obtain the masterbatch; (4) Add the masterbatch into the internal mixer, add sulfur and accelerator (composed of sulfenamide accelerator CBS and thiazole accelerator MBTS in a weight ratio of 1.7:0.6), mix for 140 s, and discharge when the temperature is less than or equal to 100°C; (5) Thin pass on the open mill, and then sheet; cool to 25°C, and then store for 24 h to obtain the finished product.

[0035] Table 1: Amounts of raw materials in examples 1-5 and comparative examples 1-2

[0036] Examples 6-12 Examples 6-12 respectively provide an NBR oil seal for an automobile engine system and a preparation method thereof.

[0037] The differences between the above examples and example 1 are as follows.

[0038] In example 6, the NBR rubber is composed of NBR 3345 rubber and NBR 1965 rubber in a weight ratio of 67:33.

[0039] In example 7, the NBR rubber is composed of NBR 3345 rubber and NBR 1965 rubber in a weight ratio of 60:40.

[0040] In example 8, in the preparation method of the carbon black, the carbon black is prepared by mixing semi-reinforcing carbon black N774, medium particle thermal cracking carbon black N990, and polyethylene glycol monomethyl ether in a weight ratio of 70:25:1.8.

[0041] In Example 9: the preparation method of carbon black, the carbon black was prepared from semi-reinforcing carbon black N774, medium particle thermal cracking carbon black N990 and polyethylene glycol monomethyl ether with a weight ratio of 60:40:1.

[0042] In Example 10: the carbon black was directly mixed from semi-reinforcing carbon black N774, medium particle thermal cracking carbon black N990 and polyethylene glycol monomethyl ether with a weight ratio of 68:30:1.5.

[0043] In Example 11: the antioxidant was composed of quinoline antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline, p-phenylenediamine antioxidant N-isopropyl-N'-phenyl-p-phenylenediamine and heterocyclic antioxidant 2-mercaptobenzimidazole with a weight ratio of 2:1:2.

[0044] In Example 12: the antioxidant was composed of quinoline antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline, p-phenylenediamine antioxidant N-isopropyl-N'-phenyl-p-phenylenediamine and heterocyclic antioxidant 2-mercaptobenzimidazole with a weight ratio of 1.3:1.6:1.3.

[0045] The other process parameters in the above examples are the same as those in Example 1.

[0046] Comparative Example Comparative Example 1-2 Comparative Example 1-2 respectively provides an NBR oil seal and a preparation method thereof.

[0047] The above comparative examples and Example 1 are different in that the amounts of the raw material components are different, as shown in Table 1.

[0048] The other process parameters in the above comparative examples are the same as those in Example 1.

[0049] Comparative Example 3-5 Comparative Example 3-5 respectively provides an NBR oil seal and a preparation method thereof.

[0050] The above comparative examples and Example 1 are different in that the amounts of the raw material components are different, as shown in Table 1.

[0051] In Comparative Example 3: the NBR rubber was composed of NBR 3345 rubber and NBR 1965 rubber with a weight ratio of 30:70.

[0052] In Comparative Example 4: the carbon black was composed of semi-reinforcing carbon black N774 and medium particle thermal cracking carbon black N990 with a weight ratio of 68:30.

[0053] In Comparative Example 5: in the preparation method of carbon black, an equal amount of high wear-resistant furnace black N330 was used to replace the medium particle thermal cracking carbon black N990.

[0054] All other process parameters in the above comparative examples are the same as those in Example 1.

[0055] Performance testing Compression set: The compression set of NBR oil seal specimens was tested according to the test method of GB / T 7759.1-2015 under the test conditions of 120℃×70h.

[0056] Elongation: The elongation of the NBR oil seal specimen was determined according to GB / T 528. After aging at 120℃ for 70h, the elongation of the NBR oil seal specimen was tested. The elongation change rate was calculated as follows: Elongation change rate = (Elongation of the aged specimen - Elongation of the original specimen) / Elongation of the original specimen × 100%.

[0057] Hardness: The hardness of the NBR oil seal sample was determined according to GB / T 531.1; the hardness of the NBR oil seal sample was tested after aging at 120℃ for 70h; the hardness change value was calculated, and the hardness change value = hardness of the aged sample - hardness of the original sample.

[0058] Test results are shown in Table 2.

[0059] Table 2 Performance test results of NBR oil seals in the examples and comparative examples

[0060] As shown in Table 2 above, the NBR oil seals for automotive engine systems prepared using the technical solution provided in this application exhibit a compression set of ≤16.0% after 70 hours at a test temperature of 120℃; the elongation of the NBR oil seal products is ≥410%, and the hardness is 65-69; the elongation change rate after hot air aging can be controlled within -22%, and the hardness change can be controlled within 7. These test results demonstrate that the NBR oil seal material prepared using the technical solution of this application achieves a perfect combination of excellent heat resistance and compression set.

[0061] By comparing the test results of Examples 1-5 and Comparative Examples 1-2, it can be seen that the amount of each raw material component has a significant impact on the performance of the NBR oil seal material. In Comparative Examples 1-2, the amounts of each raw material component were mismatched, resulting in NBR oil seal materials with poor performance. In contrast, the present application, by precisely matching the amounts of each raw material component, produces a finished product with excellent performance.

[0062] Comparing the test results of Examples 1, 6-7, and Comparative Example 3, it can be seen that the type of NBR rubber has a significant impact on the performance of NBR oil seal materials. In Comparative Example 3, the NBR rubber was composed of a mixture of NBR 3345 rubber and NBR1965 rubber in a weight ratio of 30:70, resulting in a material with poor performance. In contrast, this application utilizes a mixture of NBR 3345 rubber and NBR 1965 rubber in a weight ratio of 65-75:25-35 to prepare an NBR oil seal material with excellent pressure deformation properties and heat resistance.

[0063] Comparing the test results of Examples 1, 8-10, and Comparative Examples 4-5, it can be seen that the preparation method of carbon black has a significant impact on the performance of NBR oil seal materials. In Comparative Example 4, the carbon black was composed of a mixture of semi-reinforcing carbon black N774 and medium-particle pyrolytic carbon black N990 in a weight ratio of 68:30. In Comparative Example 5, the carbon black was prepared by replacing an equal amount of medium-particle pyrolytic carbon black N990 with high-abrasion-resistant furnace black N330, resulting in NBR oil seal materials with poor performance. In contrast, the carbon black prepared in this application using a weight ratio of semi-reinforcing carbon black N774, medium-particle pyrolytic carbon black N990, and polyethylene glycol monomethyl ether in a weight ratio of 60-75:20-40:1-2 results in NBR oil seal materials with excellent pressure transition properties and heat resistance.

[0064] By comparing the test results of Examples 1 and 11-12, it can be seen that the type of antioxidant has a significant impact on the performance of NBR oil seal materials. This application utilizes a mixture of quinoline antioxidants, p-phenylenediamine antioxidants, and heterocyclic antioxidants in a weight ratio of 1-1.3:1.6-2:1-1.3 to form an antioxidant, which further improves the performance of NBR oil seal materials.

[0065] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. An NBR oil seal for an automotive engine system, characterized in that, Specifically, it includes the following components in parts by weight: 100 parts NBR rubber, 80-115 parts carbon black, 10-15 parts TP759 heat-resistant plasticizer, 5-7 parts zinc oxide, 0.5-1.5 parts stearic acid, 3-6 parts antioxidant, 1-2 parts protective wax, 0.1-0.5 parts sulfur, and 1.5-3 parts accelerator; The NBR rubber is composed of a mixture of NBR 3345 rubber and NBR 1965 rubber in a weight ratio of 65-75:25-35; The carbon black is prepared from semi-reinforcing carbon black N774, medium-particle thermally decomposed carbon black N990, and polyethylene glycol monomethyl ether in a weight ratio of 60-75:20-40:1-2; the molecular weight of the polyethylene glycol monomethyl ether is 1800-2200. The antioxidant is composed of a mixture of quinoline antioxidants, p-phenylenediamine antioxidants, and heterocyclic antioxidants in a weight ratio of 1-2:1-2:1-2; The accelerator is prepared in a weight ratio of 1-2: It is composed of a mixture of 0.5-1% sulfenamide accelerator CBS and thiazole accelerator MBTS.

2. The NBR oil seal for automotive engine systems according to claim 1, characterized in that, Specifically, it includes the following components in parts by weight: 100 parts NBR rubber, 90-106 parts carbon black, 11-14 parts TP759 heat-resistant plasticizer, 5.5-6.5 parts zinc oxide, 0.7-1.2 parts stearic acid, 4-5 parts antioxidant, 1.2-1.8 parts protective wax, 0.2-0.4 parts sulfur, and 2-2.5 parts accelerator.

3. The NBR oil seal for automotive engine systems according to claim 1, characterized in that, The NBR rubber is composed of a mixture of NBR 3345 rubber and NBR 1965 rubber in a weight ratio of 67-73:27-33.

4. The NBR oil seal for an automotive engine system according to claim 1, characterized in that, The carbon black is prepared from semi-reinforcing carbon black N774, medium particle pyrolysis carbon black N990, and polyethylene glycol monomethyl ether in a weight ratio of 65-70:25-35:1.2-1.

8.

5. The NBR oil seal for an automotive engine system according to claim 1, characterized in that, The carbon black is prepared by dissolving polyethylene glycol monomethyl ether in toluene and thionyl chloride, reacting at 70-80℃ for 6-10 hours, and then rotary evaporating to obtain activated polyethylene glycol monomethyl ether. Semi-reinforcing carbon black N774 and medium-particle thermally decomposed carbon black N990 were dispersed in anhydrous N,N-dimethylformamide solvent and ultrasonically dispersed. Then, activated polyethylene glycol monomethyl ether and 4-dimethylaminopyridine were added, and the mixture was stirred and reacted at 80-100℃ for 24-48 hours under nitrogen protection. After the reaction was completed, the mixture was cooled to room temperature. After washing and drying, carbon black was obtained.

6. The NBR oil seal for an automotive engine system according to claim 5, characterized in that, In the method for preparing carbon black, the weight ratio of toluene, sulfoxide and polyethylene glycol monomethyl ether is 8-12:15-25:1; the weight ratio of N,N-dimethylformamide to the total weight of raw materials is 1-5:1; and the weight ratio of 4-dimethylaminopyridine to polyethylene glycol monomethyl ether is 0.005-0.02:

1.

7. The NBR oil seal for an automotive engine system according to claim 1, characterized in that, The antioxidant is composed of a mixture of quinoline antioxidants, p-phenylenediamine antioxidants, and heterocyclic antioxidants in a weight ratio of 1-1.3:1.6-2:1-1.

3.

8. The NBR oil seal for an automotive engine system according to claim 1, characterized in that, Among the antioxidants, the quinoline antioxidant is 2,2,4-trimethyl-1,2-dihydroquinoline, the p-phenylenediamine antioxidant is N-isopropyl-N'-phenyl-p-phenylenediamine, and the heterocyclic antioxidant is 2-mercaptobenzimidazole.

9. The NBR oil seal for an automotive engine system according to claim 1, characterized in that, The accelerator is composed of a mixture of sulfenamide accelerator CBS and thiazole accelerator MBTS in a weight ratio of 1.5-2:0.5-0.

7.

10. The method for preparing an NBR oil seal for an automotive engine system according to any one of claims 1-9, characterized in that, Specifically, the following steps are performed sequentially: (1) Start the internal mixer, add NBR rubber, zinc oxide, stearic acid, antioxidant and protective wax into the internal mixer, and mix for 60-80 seconds with a speed of 35-45 r / min and a pressure of 4-6 bar applied by the top plug; (2) Add carbon black and TP759 heat-resistant plasticizer, and heat at a speed of 15-25 r / min and a pressure of 4-6 bar until the temperature reaches 130-140℃, with the pressure increased and the exhaust gas 1-2 times in between; (3) After cooling, thinning, filtering, and sheeting, the masterbatch is obtained after cooling and standing for more than 8 hours. (4) Add the masterbatch to the internal mixer, add sulfur and accelerator, mix for 120-150s, and discharge when the temperature is ≤100℃; (5) After passing through a thin tube and extruding the strip, cool it to 20-25℃ and let it stand for 16-24 hours to obtain the finished product.

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