Rubber material for oil seal

Abstract

The present invention relates to a rubber material for oil seals, comprising the following raw materials, measured in parts by weight: 100 parts of nitrile rubber or hydrogenated nitrile rubber, 35-44 parts of carbon black, 1-4 parts of a modified thermally conductive filler, 0.3-0.8 parts of a modified thermally conductive self-lubricating filler, 2 parts of stearic acid, 5 parts of zinc oxide, 0.5-2 parts of an antioxidant, 3-10 parts of a plasticizer, 1-2 parts of a vulcanization accelerator, and 1-8 parts of a vulcanizing agent. The present invention preferably uses nano-sheet or nano-tubular boron nitride. The nitrile rubber or hydrogenated nitrile rubber is grafted onto the surface of the boron nitride using a Haake internal mixer, thereby improving the dispersibility and compatibility of the boron nitride in the rubber matrix. Oil seals prepared using the rubber material of the present invention have the characteristics of high thermal conductivity and long service life.

Description

Technical Field

[0001] The present invention relates to the technical field of oil seal preparation, in particular to a rubber material for oil seals. Background Art

[0002] Currently, rubber oil seals account for the largest proportion of oil seals used in the domestic and international oil seal fields, with the main rubber materials including nitrile rubber, hydrogenated nitrile rubber, fluororubber, etc.

[0003] During dynamic mechanical operation, such as in automobile engines, the lip of the engine oil seal is held tightly against the crankshaft with a certain amount of pressure. Due to the high-speed friction between the crankshaft and the lip, a large amount of heat is generated at the oil seal lip. If this heat cannot be dissipated into the engine oil in a timely manner, the temperature of the oil seal lip will rise significantly. For rubber materials, a temperature increase of 10°C generally doubles the theoretical lifespan of the rubber.

[0004] Therefore, improving the thermal conductivity of the oil seal rubber material and transferring the heat generated by the lip to the engine oil in a timely manner will help reduce the temperature of the oil seal and extend the service life of the oil seal. For example, invention patent CN106317712B adds modified graphene to the engine oil seal fluororubber, which greatly reduces the friction coefficient of the fluororubber material and greatly improves the thermal conductivity, thereby significantly reducing the wear of the automobile engine oil seal lip, reducing the lip temperature, and extending the service life of the automobile engine oil seal. In addition, boron nitride is also often used to prepare thermal conductive material additives. For example, invention patent CN113861665A discloses a high thermal conductivity boron nitride / polyurethane thermal conductive composite material and its preparation method; invention patent CN106243715B discloses a boron nitride / high thermal conductivity polyimide composite material and its preparation method. The above patents all show that boron nitride is feasible for preparing polymer thermal conductive composite materials. Summary of the Invention

[0005] In order to solve the above-mentioned problems in the prior art, the present invention proposes a method of partially replacing carbon black with modified boron nitride, compounding the modified boron nitride with commonly used rubber materials for oil seals such as nitrile rubber and hydrogenated nitrile rubber, to prepare a rubber material for nitrile rubber / carbon black / modified boron nitride or hydrogenated nitrile rubber / carbon black / modified boron nitride oil seals. The oil seal prepared using the rubber material has the advantages of good thermal conductivity and long service life.

[0006] The present invention adopts the following technical solutions:

[0007] A rubber material for oil seals comprises the following raw material components, measured in parts by weight: 100 parts of nitrile rubber or hydrogenated nitrile rubber, 35-44 parts of carbon black, 1-4 parts of modified thermally conductive filler, 0.3-0.8 parts of modified thermally conductive self-lubricating filler, 2 parts of stearic acid, 5 parts of zinc oxide, 0.5-2 parts of an antioxidant, 3-10 parts of a plasticizer, 1-2 parts of a vulcanization accelerator, and 1-8 parts of a vulcanizing agent.

[0008] The carbon black includes at least one of N330, N550 or N990.

[0009] The modified thermal conductive filler comprises the following raw materials: nitrile rubber or hydrogenated nitrile rubber, boron nitride, 1,4-bis-tert-butyl peroxyisopropylbenzene and triallyl isocyanurate;

[0010] The weight ratio of nitrile rubber or hydrogenated nitrile rubber, boron nitride, 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate is 100:100-150:0.04-0.10:0.03-0.05.

[0011] The preparation method of the modified thermally conductive filler is as follows:

[0012] Add nitrile rubber or hydrogenated nitrile rubber into a Haake internal mixer, and shear at 175-195°C and 40-100 r / min until the torque curve is stable. Add boron nitride, triallyl isocyanurate and 1,4-bis-tert-butyl peroxyisopropylbenzene, and shear until the torque curve is stable. The material is discharged and cooled to obtain a modified thermal conductive filler.

[0013] The antioxidant includes but is not limited to antioxidant RD, antioxidant 4010NA or antioxidant NBC; the plasticizer includes but is not limited to plasticizer NB-4, plasticizer TP-95, and plasticizer TP-759.

[0014] The vulcanization accelerator is triallyl isocyanurate; and the vulcanizing agent is 1,4-bis-tert-butyl peroxyisopropylbenzene.

[0015] In particular, the selection principle of nitrile rubber or hydrogenated nitrile rubber for boron nitride modification is: when the main raw material of the rubber raw rubber for preparing the oil seal is nitrile rubber, nitrile rubber is selected to modify boron nitride; when the main raw material of the rubber raw rubber for preparing the oil seal is hydrogenated nitrile rubber, hydrogenated nitrile rubber is selected to modify boron nitride.

[0016] The purpose of using boron nitride modified with nitrile rubber or hydrogenated nitrile rubber is to improve its dispersibility and compatibility within the rubber matrix. Boron nitride is an inorganic filler. When used directly as a thermally conductive filler in organic rubber matrices such as nitrile rubber or hydrogenated nitrile rubber, it is difficult to evenly disperse within the rubber matrix due to its significant polarity differences. The interaction with the rubber matrix is ​​also weak, resulting in a decrease in the physical and mechanical properties of the resulting oil seal rubber material, such as tear strength and flexural properties. This decrease in tear strength can lead to premature oil seal failure, while decreased flexural properties can cause premature oil leakage. Both of these conditions are detrimental to the longevity of the oil seal.

[0017] In the preparation method of the modified thermally conductive filler, the weight ratio of nitrile rubber or hydrogenated nitrile rubber, boron nitride, 1,4-bis-tert-butylperoxyisopropylbenzene, and triallyl isocyanurate used is 100:100-150:0.04-0.10:0.03-0.05. The purpose of adding 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate is that 1,4-bis-tert-butylperoxyisopropylbenzene is a peroxide crosslinking agent. Under high temperature, it generates active free radicals, which cause covalent crosslinking between the nitrile rubber or hydrogenated nitrile rubber and the boron nitride, resulting in the grafting of the nitrile rubber or hydrogenated nitrile rubber onto the surface of the boron nitride. This improves the dispersibility of the boron nitride in the rubber matrix and its compatibility with the rubber matrix, thereby effectively exerting the beneficial effects of the modified boron nitride mentioned above. Triallyl isocyanurate is a cross-linking accelerator that can improve the cross-linking efficiency of 1,4-bis-tert-butylperoxyisopropylbenzene.

[0018] If the amount of 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate added is too small, effective covalent crosslinking between the nitrile rubber or hydrogenated nitrile rubber and the boron nitride will not occur. If the amount of 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate added is too large, the nitrile rubber or hydrogenated nitrile rubber will prematurely develop a three-dimensional network crosslink. When this type of nitrile rubber or hydrogenated nitrile rubber with pre-existing three-dimensional crosslinking is used in the preparation of rubber materials for oil seals, it cannot be effectively dispersed during the mixing stage, easily forming "fish eyes," which seriously affects the overall performance of the oil seal. Therefore, the key technical point of the present invention lies in controlling the amount of 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate. The key point is to ensure effective grafting of the nitrile rubber or hydrogenated nitrile rubber with the boron nitride without forming a three-dimensional network structure.

[0019] In the preparation method of the modified thermally conductive filler, to verify whether the nitrile rubber or hydrogenated nitrile rubber has formed a three-dimensional network structure, the modified boron nitride is wrapped with a 200-mesh copper mesh and placed in toluene, refluxed at 115°C for 4 hours. The mesh is then removed and inspected for any undissolved material. If there is visible residue on the mesh, it is a cross-linked polymer that is difficult to dissolve in toluene. Research has shown that when the weight ratio of 1,4-bis-tert-butylperoxyisopropylbenzene to nitrile rubber or hydrogenated nitrile rubber exceeds 0.10%, visible residue will appear on the mesh. Therefore, the amount of 1,4-bis-tert-butylperoxyisopropylbenzene should not exceed 0.10% of the nitrile rubber or hydrogenated nitrile rubber. The condensate refluxed liquid is then filtered while hot, and the filter cake is subjected to thermogravimetric analysis and compared with unmodified boron nitride. Studies have shown that when the amount of 1,4-bis-tert-butylperoxyisopropylbenzene is less than 0.04% of the amount of NBR or HNBR used, the mass loss of the filter cake and unmodified boron nitride at room temperature to 560°C is consistent. This indicates that the amount of crosslinker 1,4-bis-tert-butylperoxyisopropylbenzene is too small to initiate a grafting reaction between the NBR or HNBR and the boron nitride.

[0020] The boron nitride is in nano-flake or nano-tubular form, not nano-granular. This is because, when the boron nitride is in nano-flake or nano-tubular form, adding a small amount of modified boron nitride can form a heat conduction path in the rubber matrix, effectively dissipating the heat generated by the oil seal lip. If it is in granular form, a large amount of boron nitride is required to form a heat conduction path. However, if the boron nitride addition is too large, even after modification, the physical and mechanical properties of the oil seal rubber material, such as tear strength, flexural properties, and resilience, will be significantly reduced, seriously affecting the overall performance of the oil seal.

[0021] The modified heat-conductive self-lubricating filler comprises the following raw materials: ultra-high molecular weight polyethylene, graphene, 1,4-bis-tert-butyl peroxyisopropylbenzene and triallyl isocyanurate;

[0022] The weight ratio of ultra-high molecular weight polyethylene, graphene, 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate is 35-45:100-150:0.02-0.03:0.01-0.015.

[0023] The preparation method of the modified thermally conductive self-lubricating filler is as follows:

[0024] Ultra-high molecular weight polyethylene is added into a Hake internal mixer and sheared at 200-250° C. until the torque curve is stable. Graphene, triallyl isocyanurate and 1,4-bis-tert-butyl peroxyisopropylbenzene are added and sheared until the torque curve is stable. The material is discharged and cooled to obtain a modified thermal conductive self-lubricating filler, namely ultra-high molecular weight polyethylene modified graphene.

[0025] The principle behind using ultra-high molecular weight polyethylene (UHMWPE) to modify graphene is that under high temperature and peroxide initiation, reactive free radicals are generated within the UHMWPE molecular chain. These reactive free radicals react with oxygen-containing functional groups such as hydroxyl, carboxyl, and ester groups on the graphene surface, forming strong covalent crosslinks.

[0026] The purpose of using UHMWPE to modify graphene is to combine the high thermal conductivity of graphene with the high wear resistance and self-lubricating properties of UHMWPE. Furthermore, the UHMWPE-grafted graphene surface facilitates its dispersion within the rubber matrix during the subsequent mixing process for oil seal materials. This is because the long UHMWPE chains attached to the graphene surface are more likely to physically entangle with the rubber molecular chains, pulling them together and dispersing them evenly.

[0027] The weight ratio of ultra-high molecular weight polyethylene (UHMWPE), graphene, 1,4-bis-tert-butylperoxyisopropylbenzene (1,4-bis-tert-butylperoxyisopropylbenzene), and triallyl isocyanurate is 35-45:100-150:0.02-0.03:0.01-0.015. The addition of 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate is due to the fact that 1,4-bis-tert-butylperoxyisopropylbenzene is a peroxide crosslinker. Under high temperature, it generates active free radicals, which covalently crosslink the UHMWPE with the graphene, grafting the UHMWPE onto the graphene surface and effectively achieving the beneficial effects of the modified graphene mentioned above. Triallyl isocyanurate acts as a crosslinking accelerator, enhancing the crosslinking efficiency of 1,4-bis-tert-butylperoxyisopropylbenzene.

[0028] If the amount of 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate added is too small, the ultra-high molecular weight polyethylene and graphene cannot form effective covalent crosslinks. If the amount of 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate added is too large, the ultra-high molecular weight polyethylene will prematurely form three-dimensional network crosslinks. When this type of ultra-high molecular weight polyethylene with pre-existing three-dimensional network crosslinks is used in the preparation of rubber materials for oil seals, it cannot be effectively dispersed during the mixing stage and is prone to forming "fish eyes", which seriously affects the overall performance of the oil seal. Therefore, the key technical point of the present invention is to control the amount of 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate. The control point is to enable effective grafting of the ultra-high molecular weight polyethylene and graphene without causing the ultra-high molecular weight polyethylene to form a three-dimensional network structure.

[0029] The number-average molecular weight of the ultra-high molecular weight polyethylene (UHMWPE) is 1.5 to 4.5 million. If the molecular weight is too low, the UHMWPE will not be able to impart good self-lubricity and dispersibility to the modified graphene in the rubber matrix. If the molecular weight is too high, processing difficulties may arise, such as increased equipment wear and increased processing costs.

[0030] In summary, compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. The present invention utilizes rational technical means to covalently graft nitrile rubber or hydrogenated nitrile rubber onto the surface of boron nitride to produce modified boron nitride. Compared to direct addition of boron nitride, the addition of modified boron nitride facilitates its effective dispersion within the rubber matrix and improves compatibility with the rubber matrix. While leveraging the high thermal conductivity of boron nitride, it also avoids significant degradation of the physical and mechanical properties of the oil seal rubber material, such as tear strength and flexural properties, thereby enabling the production of highly thermally conductive, long-life oil seals.

[0032] 2. The present invention, by preferably using nano-sheet or nano-tubular boron nitride, can ensure high thermal conductivity of the rubber material for oil seals with the addition of a small amount, while taking into account the physical and mechanical properties of the rubber material for oil seals, such as tear strength, flexural properties, and resilience, thereby producing an oil seal with high thermal conductivity and long life.

[0033] 3. By adding modified boron nitride and modified graphene to the production formula of oil seal rubber, the oil seal rubber material is given high thermal conductivity, high wear resistance and other properties, so that high thermal conductivity and long life oil seals can be prepared. DETAILED DESCRIPTION

[0034] The present invention will be further described below with reference to specific examples, but they do not constitute any limitation to the present invention.

[0035] In each embodiment of the present invention, the Haake internal mixer used is a HAAKE (polylab) type produced by HAAKE Company of Germany.

[0036] In each embodiment of the present invention, the specific information of each raw material is as follows:

[0037] Nitrile butadiene rubber, DN2144, Lanzhou Petrochemical Company of Sinopec.

[0038] Hydrogenated nitrile rubber, Therban A3407, Lanxess Chemical Co., Ltd., Germany.

[0039] Ultra-high molecular weight polyethylene, PE-UHMW GK01, molecular weight 4 million, Sinopec Yanshan Branch.

[0040] Carbon black, N550, Jiangxi Black Cat Carbon Black Co., Ltd.

[0041] Flake boron nitride, color: white, flake diameter: 1-3μm, average thickness: <100nm, Angxing New Carbon Materials Changzhou Co., Ltd.

[0042] Granular boron nitride, color: white, average particle size: <100nm, Angxing New Carbon Materials Changzhou Co., Ltd.

[0043] Stearic acid, analytical grade, was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0044] Zinc oxide, analytical grade, was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0045] Antioxidant, 4010NA, analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.

[0046] Plasticizer, TP-95, industrial grade, Shanghai Rohm and Haas Chemical Co., Ltd.

[0047] Triallyl isocyanurate, analytical grade, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0048] 1,4-Di-tert-butylperoxyisopropylbenzene, analytical grade, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0049] Example 1

[0050] This embodiment provides a method for preparing a modified thermally conductive filler, the specific details of which are as follows:

[0051] Nitrile-butadiene rubber was added to a Haake internal mixer and sheared at 180°C and 70 rpm until the torque curve stabilized. Boron nitride, triallyl isocyanurate, and 1,4-bis-tert-butylperoxyisopropylbenzene were then added and sheared until the torque curve stabilized to produce modified boron nitride. The weight ratio of nitrile rubber, flake boron nitride, 1,4-bis-tert-butylperoxyisopropylbenzene, and triallyl isocyanurate was 100:100:0.08:0.04.

[0052] Example 2

[0053] Example 2: A modified thermally conductive filler, i.e., modified boron nitride, was prepared using the same method as Example 1, except that the raw material ratios were different. Specifically, the weight ratio of nitrile rubber, flake boron nitride, 1,4-bis-tert-butylperoxyisopropylbenzene, and triallyl isocyanurate was 100:100:0.02:0.02.

[0054] Example 3

[0055] Example 3: Modified thermal conductive filler, i.e., modified boron nitride, was prepared using the same preparation method as Example 1, except that the raw material ratios were different. Specifically, the weight ratio of nitrile rubber, flake boron nitride, 1,4-bis-tert-butylperoxyisopropylbenzene, and triallyl isocyanurate was 100:100:0.15:0.08.

[0056] Example 4

[0057] Example 4: A modified thermal conductive filler, i.e., modified boron nitride, is prepared by the preparation method of Example 1, except that the boron nitride selected is granular.

[0058] Examples 5 to 8

[0059] 100 parts of nitrile rubber, 40 parts of carbon black, 1.5 parts of modified boron nitride, 0.5 parts of modified graphene, 2 parts of stearic acid, 5 parts of zinc oxide, 1 part of antioxidant 4010NA, 4 parts of plasticizer TP-95, 1.5 parts of vulcanization accelerator triallyl isocyanurate, and 2 parts of vulcanizing agent 1,4-bis-tert-butylperoxyisopropylbenzene were mixed uniformly in an internal mixer to obtain a rubber mix. The rubber mix was then formed into a rubber blank for oil seals on a precision preforming machine. The rubber blank and a surface-treated metal skeleton were vulcanized using an electric hot plate vulcanizer. The lip was then cut to standard dimensions and a spring was installed to obtain an oil seal test piece. Examples 5 to 8 correspond to the modified boron nitride prepared using the methods of Examples 1 to 4, respectively, and are otherwise identical.

[0060] The modified graphene is prepared by adding ultra-high molecular weight polyethylene (UHMWPE) to a Haake internal mixer and shearing the mixture at 235°C and 70 rpm until the torque curve reaches a plateau. Graphene, triallyl isocyanurate (TRII), and 1,4-bis-tert-butylperoxyisopropylbenzene (1,4-bis-tert-butylperoxyisopropylbenzene) are then added and sheared until the torque curve reaches a plateau. The weight ratio of UHMWPE, graphene, 1,4-bis-tert-butylperoxyisopropylbenzene, and triallyl isocyanurate is 35:100:0.02:0.01.

[0061] Examples 9-10

[0062] Examples 9-10 used the method of Example 5 to prepare oil seal test pieces, except that the amounts of modified boron nitride used were 4 parts and 10 parts, respectively.

[0063] Comparative Example 1

[0064] Comparative Example 1: An oil seal test piece was prepared using the method of Example 5, except that the boron nitride used was unmodified granular boron nitride.

[0065] Comparative Example 2

[0066] Comparative Example 2: An oil seal test piece was prepared using the method of Example 5, except that the boron nitride used was unmodified flaky boron nitride.

[0067] Comparative Example 3

[0068] Comparative Example 3: An oil seal test piece was prepared using the method of Example 5, except that the graphene used was unmodified graphene.

[0069] The oil seal test pieces prepared in Experimental Examples 5 to 10 and Comparative Examples 1 to 3 were subjected to thermal conductivity measurement and simulated bench testing. The simulated bench testing was conducted in accordance with GB / T 13871.4-2007, with the following parameters: temperature 140°C, spindle speed 6000 r / min -1 The test medium is 32# machinery oil. The test data are shown in Table 1.

[0070] Table 1

[0071]

[0072]

[0073] Comparing Comparative Example 1 and Comparative Example 2, it can be seen that the thermal conductivity of flake boron nitride is higher than that of granular boron nitride, because flake boron nitride is easier to form a heat conduction path in the rubber matrix, so the operating time of the oil seal is also significantly increased.

[0074] Comparing Comparative Example 2 and Example 5 shows that the modified flake boron nitride is more evenly dispersed in the rubber matrix, forming a more complete thermal conductivity path. Consequently, the thermal conductivity of Example 5 is 40.5% higher than that of Comparative Example 2. Furthermore, the modified flake boron nitride exhibits a stronger interaction with the rubber matrix. These two factors combined result in a 21.0% increase in the operating time of Example 5 compared to Comparative Example 2.

[0075] Comparing Comparative Example 3 and Example 5, it can be seen that after graphene is modified by an appropriate method, it is easier to bring about wear resistance of the rubber matrix. Therefore, the operating time of Example 5 is increased by 19.1% compared with Comparative Example 3.

[0076] In Example 6, since the amount of 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate used in the boron nitride modification process was too small, the modification was unsuccessful, so the thermal conductivity and operating time were significantly reduced compared with Example 5.

[0077] In Example 7, excessive amounts of 1,4-bis-tert-butyl peroxyisopropylbenzene and triallyl isocyanurate were used during the boron nitride modification process, resulting in crosslinking of the nitrile rubber grafted onto the boron nitride surface. This crosslinked structure was difficult to evenly disperse within the rubber matrix during processing, and also formed "fisheyes" and stress concentration points in the oil seal test piece. Consequently, the operating time was even shorter than that of Comparative Example 1.

[0078] Comparing Example 8 with Example 5, it can be seen that even if a suitable modification method is used, the thermal conductivity and operating time of granular boron nitride are significantly worse than those of flake boron nitride.

[0079] Comparing Examples 5, 9, and 10, it can be seen that increasing the amount of modified boron nitride from 1.5 to 4 parts significantly improves thermal conductivity, but the run time does not significantly increase. This is because increasing the amount of boron nitride added degrades the physical and mechanical properties of the rubber. The positive effect of improved thermal conductivity is balanced by the negative effect of decreased physical and mechanical properties. This is clearly demonstrated in Example 10, where increasing the amount of modified boron nitride to 10 parts significantly reduces the run time.

[0080] Any numerical value mentioned in the present invention includes all values ​​that increase by one unit each time from the lowest value to the highest value if there is only an interval of two units between any minimum value and any maximum value. For example, if the amount of a component, or the value of a process variable such as temperature, pressure, time, etc. is stated to be 50-90, it is meant in this specification to specifically list values ​​such as 51-89, 52-88... and 69-71 and 70-71. For non-integer values, it is appropriate to consider 0.1, 0.01, 0.001 or 0.0001 as one unit. These are just some special examples. In this application, in a similar manner, all possible combinations of numerical values ​​between the listed lowest value and the listed highest value are considered to have been disclosed.

[0081] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation of the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein. On the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A rubber material for oil seal, characterized in that: The composition comprises the following raw materials in parts by weight: 100 parts of nitrile rubber or hydrogenated nitrile rubber, 35-44 parts of carbon black, 1-4 parts of modified thermal conductive filler, 0.3-0.8 parts of modified thermal conductive self-lubricating filler, 2 parts of stearic acid, 5 parts of zinc oxide, 0.5-2 parts of antioxidant, 3-10 parts of plasticizer, 1-2 parts of vulcanization accelerator and 1-8 parts of vulcanizing agent. The modified thermal conductive filler comprises the following raw materials: nitrile rubber or hydrogenated nitrile rubber, boron nitride, 1,4-bis-tert-butyl peroxyisopropylbenzene and triallyl isocyanurate; The weight ratio of nitrile rubber or hydrogenated nitrile rubber, boron nitride, 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate is 100:100-150:0.04-0.10:0.03-0.05; The modified thermally conductive filler is prepared by adding nitrile rubber or hydrogenated nitrile rubber to a Haake internal mixer, shearing the mixture at 175-195° C. and 40-100 r / min until the torque curve is stable, adding boron nitride, triallyl isocyanurate, and 1,4-bis-tert-butyl peroxyisopropylbenzene, shearing the mixture until the torque curve is stable, and cooling the mixture to obtain the modified thermally conductive filler. The modified heat-conductive self-lubricating filler comprises the following raw materials: ultra-high molecular weight polyethylene, graphene, 1,4-bis-tert-butyl peroxyisopropylbenzene and triallyl isocyanurate; The weight ratio of ultra-high molecular weight polyethylene, graphene, 1,4-bis-tert-butylperoxyisopropylbenzene and triallyl isocyanurate is 35-45:100-150:0.02-0.03:0.01-0.015; The preparation method of the modified thermally conductive self-lubricating filler is as follows: ultra-high molecular weight polyethylene is added to a Hake internal mixer, and sheared at 200-250° C. until the torque curve is stable, and graphene, triallyl isocyanurate, and 1,4-bis-tert-butyl peroxyisopropylbenzene are added and sheared until the torque curve is stable. The material is discharged and cooled to obtain the modified thermally conductive self-lubricating filler.

2. The rubber material for oil seal according to claim 1, characterized in that: The carbon black includes at least one of N330, N550 or N990.

3. The rubber material for oil seal according to claim 1, characterized in that: The boron nitride is in the form of nanosheets or nanotubes.

4. The rubber material for oil seal according to claim 1, characterized in that: The number average molecular weight of the ultra-high molecular weight polyethylene is 1.5 to 4.5 million.

5. The rubber material for oil seal according to claim 1, characterized in that: The antioxidant includes but is not limited to antioxidant RD, antioxidant 4010NA or antioxidant NBC; the plasticizer includes but is not limited to plasticizer NB-4, plasticizer TP-95, and plasticizer TP-759.

6. The rubber material for oil seal according to claim 1, characterized in that: The vulcanization accelerator is triallyl isocyanurate; and the vulcanizing agent is 1,4-bis-tert-butyl peroxyisopropylbenzene.

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