Highly abrasion-resistant nitrile rubber sealing material and method for producing the same

Abstract

The application discloses a kind of high wear-resistant nitrile rubber sealing material and preparation method thereof, the nitrile rubber sealing material is according to mass parts, including following components: nitrile rubber matrix 100 parts, zinc oxide 2~10 parts, stearic acid 0.5~5 parts, sulfur masterbatch 0.5~5 parts, accelerator 0.5~5 parts, antioxidant 2~10 parts, plasticizer 1~10 parts, carbon black 10~30 parts, molybdenum disulfide or silane coupling agent modified molybdenum disulfide 5~30 parts.The sealing material of the application keeps good mechanical property and wear resistance at the same time, has excellent heat conduction performance, can timely remove heat generated in sealing process or external conduction, reduce the thermal aging rate of sealing material, prolong the service life of material.

Description

Technical Field

[0001] This invention belongs to the technical field of nitrile rubber-based sealing materials and their preparation technology, and relates to a high wear-resistant nitrile rubber sealing material and its preparation method. Background Technology

[0002] Rubber-based composite materials are important sealing materials widely used in the sealing of various equipment, especially in extreme environments (such as acid and alkali environments, high pressure environments, and high temperature environments). To ensure that rubber meets the requirements of practical application scenarios, different additives are usually used to reinforce or modify it.

[0003] In the dynamic sealing process of some equipment, to prevent oil leakage from the inside of the seal, the material is required to have excellent friction and wear resistance and oil resistance. Therefore, nitrile rubber-based composite materials are generally selected as dynamic sealing elements, and reinforcing agents, crosslinking agents, accelerators, plasticizers, etc. are added to improve the overall performance of the material. Commonly used reinforcing agents include carbon black and silica, crosslinking agents include sulfur and peroxides, and accelerators include zinc oxide and stearic acid. In addition, depending on the actual application of the material, other substances can be added or the molded material can be further treated, such as adding nano-glass microspheres to improve the wear resistance of the material, and adding nano-sized desiccants (nano-titanium dioxide, nano-alumina, etc.) to improve the flexibility of the material.

[0004] In existing technologies, nanomaterials are mostly used as additives to improve the wear resistance of nitrile rubber, but this approach is costly. In addition, nanofillers are prone to agglomeration, which means that a large amount of heat generated by friction during dynamic sealing cannot be dissipated in time, causing the material to exhibit thermal aging behavior and reducing its service life. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a sealing material that exhibits excellent oil resistance, high thermal conductivity, resistance to friction and wear, and superior sealing performance. The sealing material utilizes inexpensive industrial-grade molybdenum disulfide as an additive, significantly reducing the material's manufacturing cost. Furthermore, it has been found that the addition of carbon black and molybdenum disulfide can significantly improve the material's thermal conductivity, reduce losses due to thermal aging, and extend its service life.

[0006] Based on this, the technical solution of the present invention is as follows: A nitrile rubber sealing material, comprising the following components by weight: 100 parts of nitrile rubber matrix, 2-10 parts zinc oxide Stearic acid 0.5-5 parts, Sulfur masterbatch 0.5-5 parts, Accelerator 0.5-5 parts, Anti-aging agent 2-10 parts, Plasticizer 1-10 parts, 10-30 parts carbon black 5-30 parts of molybdenum disulfide or silane coupling agent modified molybdenum disulfide.

[0007] According to an embodiment of the present invention, the accelerator is 2,2'-dithiodibenzothiazole.

[0008] According to an embodiment of the present invention, the antioxidant is at least one selected from 2,2,4-trimethyl-1,2-dihydroquinoline polymer and 4,4'-dithiodimorpholine.

[0009] According to an embodiment of the present invention, the plasticizer is dibutyl phthalate.

[0010] According to an embodiment of the present invention, the carbon black is at least one of N330 type and N550 type.

[0011] According to an embodiment of the present invention, the acrylonitrile content in the nitrile rubber matrix is ​​25~35 wt%.

[0012] According to an embodiment of the present invention, the silane coupling agent is selected from at least one of γ-aminopropyltriethoxysilane (KH550), γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH560), and γ-methacryloyloxypropyltrimethoxysilane (KH570).

[0013] According to an embodiment of the present invention, the molybdenum disulfide is industrial-grade molybdenum disulfide.

[0014] According to an embodiment of the present invention, the method for preparing the silane coupling agent modified molybdenum disulfide is as follows: Mix 1.0–2.0 g of silane coupling agent, 0.5–1.0 g of water, and 10 mL of ethanol at 65–75 °C. After 1–3 h, add 2.0–5.0 g of molybdenum disulfide and react for 5–10 h. Preferably, after the solution has cooled naturally, filter it using a vacuum pump, wash the filter cake 3–5 times with anhydrous ethanol, and dry the filter residue to obtain the silane coupling agent-modified molybdenum disulfide.

[0015] According to an embodiment of the present invention, the zinc oxide is present in parts by weight of 2, 4, 6, 8 or 10.

[0016] According to an embodiment of the present invention, the stearic acid is present in parts by weight of 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts or 5 parts.

[0017] According to an embodiment of the present invention, the sulfur masterbatch is in the following proportions by weight: 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, or 5 parts.

[0018] According to an embodiment of the present invention, the accelerator is present in parts by weight of 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts or 5 parts.

[0019] According to an embodiment of the present invention, the antioxidant is present in parts by weight of 2, 4, 6, 8 or 10.

[0020] According to an embodiment of the present invention, the plasticizer is present in parts by weight of 1 part, 2 parts, 4 parts, 6 parts, 8 parts, or 10 parts.

[0021] According to an embodiment of the present invention, the carbon black is in the following quantities: 10 parts, 12 parts, 14 parts, 16 parts, 18 parts, 20 parts, 24 parts, 28 parts, or 30 parts by weight.

[0022] According to an embodiment of the present invention, the molybdenum disulfide or silane coupling agent modified molybdenum disulfide is present in parts by weight of 5, 10, 12, 14, 16, 18, 20, 24, 28 or 30.

[0023] This invention also provides a method for preparing the above-mentioned sealing material, the steps of which are as follows: The raw materials are mixed and molded to obtain a compound rubber; the compound rubber is vulcanized to prepare the sealing material.

[0024] According to an embodiment of the present invention, the mixing temperature is 50~70°C. Preferably, the present invention does not particularly limit the mixing time, as long as the raw materials are mixed evenly.

[0025] According to an embodiment of the present invention, the mixing is carried out on a mixing machine.

[0026] According to an embodiment of the present invention, the vulcanization temperature is 160~170℃; the vulcanization pressure is 10-20MPa, preferably 12-18MPa; and the vulcanization time is 15~35min.

[0027] According to an embodiment of the present invention, the vulcanization is carried out in a flat vulcanizing machine.

[0028] The present invention also provides the application of the above-mentioned sealing material in the preparation of hydraulic oil seals, piston seals, electronic equipment seals and high-pressure oil and gas sealing materials.

[0029] The beneficial effects of this invention are: The sealing material prepared by this invention has good thermal conductivity, which can dissipate the heat generated during the dynamic sealing process in a timely manner and effectively reduce the rubber loss caused by thermal aging. At the same time, molybdenum disulfide is selected to enhance the wear resistance of the material. Compared with the general method of adding nanomaterials, it is low in cost and easy to achieve large-scale production and application.

[0030] The sealing material of this invention maintains good mechanical properties and wear resistance while also possessing excellent thermal conductivity. It can promptly dissipate heat generated during the sealing process or conducted externally, thereby reducing the thermal aging rate of the sealing material and extending its service life.

[0031] The material of this invention maintains good overall performance while also possessing excellent airtightness, making it suitable for sealing applications with stringent gas barrier requirements. Attached Figure Description

[0032] Figure 1 This is a flowchart of the preparation process for nitrile rubber sealing materials.

[0033] Figure 2 The mechanical properties of the sealing materials prepared according to Comparative Examples 1-3 and Examples 1-7 are shown in the diagram. Detailed Implementation

[0034] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0035] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0036] Example 1 The raw materials for the sealing material consist of 100 parts by weight of nitrile rubber, 2 parts by weight of zinc oxide, 0.5 parts by weight of stearic acid, 0.5 parts by weight of sulfur masterbatch, 0.5 parts by weight of accelerator 2,2'-dithiodibenzothiazole, 1 part by weight of antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 1 part by weight of antioxidant 4,4'-dithiodimorpholine, 1 part by weight of plasticizer dibutyl phthalate, 15 parts by weight of N550 type carbon black, and 15 parts by weight of molybdenum disulfide.

[0037] Preparation of sealing materials: At 50-70°C, nitrile rubber is added to a mixing mill and plasticized for 1-2 minutes to form a rubber sheet. Then, zinc oxide, stearic acid, sulfur masterbatch, accelerator, antioxidant, plasticizer, carbon black, and molybdenum disulfide are added to the rubber sheet as it rotates with two rollers and mixed for 10-15 minutes. The resulting rubber compound is then vulcanized and crosslinked using a flat vulcanizing apparatus. The vulcanization time is 15 minutes, and the cooling time is 3-5 minutes. The required temperature is 160°C, and the required pressure is 15 MPa. A sealing material is then prepared. The material prepared in Example 1 is designated as "Example-1".

[0038] Example 2 The raw materials for the sealing material consist of 100 parts by weight of nitrile rubber, 10 parts by weight of zinc oxide, 5 parts by weight of stearic acid, 5 parts by weight of sulfur masterbatch, 5 parts by weight of accelerator 2,2'-dithiodibenzothiazole, 5 parts by weight of antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 5 parts by weight of antioxidant 4,4'-dithiodimorpholine, 10 parts by weight of plasticizer dibutyl phthalate, 15 parts by weight of N330 carbon black, and 15 parts by weight of molybdenum disulfide.

[0039] The sealing material was prepared in the same manner as in Example 1, and the material prepared in Example 2 is referred to as "Example-2".

[0040] Example 3 This method uses 100 parts by weight of nitrile rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 3 parts by weight of sulfur masterbatch, 2 parts by weight of accelerator 2,2'-dithiodibenzothiazole, 2 parts by weight of antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 2 parts by weight of antioxidant 4,4'-dithiodimorpholine, 6 parts by weight of plasticizer dibutyl phthalate, 15 parts by weight of N330 type carbon black, and 15 parts by weight of molybdenum disulfide modified with silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane KH550.

[0041] The method for preparing the silane coupling agent modified molybdenum disulfide is as follows: 1.5 g of silane coupling agent, 1.0 g of distilled water, and 10 mL of ethanol were mixed at 75 °C. After 2 h, 2.5 g of molybdenum disulfide was added, and the reaction was allowed to proceed for 8 h. Preferably, after the solution cooled naturally, it was filtered using a vacuum pump. The filter cake was washed 3-5 times with anhydrous ethanol, and the filter residue was dried at 80 °C for 24 h to obtain the silane coupling agent-modified molybdenum disulfide.

[0042] The sealing material was prepared in the same manner as in Example 1, and the material prepared in Example 3 is referred to as "Example-3".

[0043] Example 4 This method uses 100 parts by weight of nitrile rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 3 parts by weight of sulfur masterbatch, 2 parts by weight of accelerator 2,2'-dithiodibenzothiazole, 2 parts by weight of antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 2 parts by weight of antioxidant 4,4'-dithiodimorpholine, 6 parts by weight of plasticizer dibutyl phthalate, 15 parts by weight of N330 type carbon black, and 15 parts by weight of molybdenum disulfide modified with silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane KH560.

[0044] The sealing material was prepared in the same manner as in Example 1, and the material prepared in Example 4 is referred to as "Example-4".

[0045] Example 5 This method uses 100 parts by weight of nitrile rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 3 parts by weight of sulfur masterbatch, 2 parts by weight of accelerator 2,2'-dithiodibenzothiazole, 2 parts by weight of antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 2 parts by weight of antioxidant 4,4'-dithiodimorpholine, 6 parts by weight of plasticizer dibutyl phthalate, 15 parts by weight of N330 type carbon black, and 15 parts by weight of molybdenum disulfide modified with silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane KH570.

[0046] The sealing material was prepared in the same manner as in Example 1, and the material prepared in Example 5 is referred to as "Example-5".

[0047] Example 6 This method uses 100 parts by weight of nitrile rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 3 parts by weight of sulfur masterbatch, 2 parts by weight of accelerator 2,2'-dithiodibenzothiazole, 2 parts by weight of antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 2 parts by weight of antioxidant 4,4'-dithiodimorpholine, 6 parts by weight of plasticizer dibutyl phthalate, 10 parts by weight of N330 type carbon black, and 20 parts by weight of molybdenum disulfide modified with silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane KH560.

[0048] The sealing material was prepared in the same manner as in Example 1, and the material prepared in Example 6 is referred to as "Example-6".

[0049] Example 7 This method uses 100 parts by weight of nitrile rubber, 5 parts by weight of zinc oxide, 2 parts by weight of stearic acid, 3 parts by weight of sulfur masterbatch, 2 parts by weight of accelerator 2,2'-dithiodibenzothiazole, 2 parts by weight of antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 2 parts by weight of antioxidant 4,4'-dithiodimorpholine, 6 parts by weight of plasticizer dibutyl phthalate, 25 parts by weight of N330 type carbon black, and 5 parts by weight of molybdenum disulfide modified with silane coupling agent γ-(2,3-epoxypropoxy)propyltrimethoxysilane KH560.

[0050] The sealing material was prepared in the same manner as in Example 1, and the material prepared in Example 7 is referred to as "Example-7".

[0051] Comparative Example 1 The raw materials for the sealing material consist of 100 parts by weight of nitrile rubber, 10 parts by weight of zinc oxide, 5 parts by weight of stearic acid, 5 parts by weight of sulfur masterbatch, 5 parts by weight of accelerator 2,2'-dithiodibenzothiazole, 5 parts by weight of antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 5 parts by weight of antioxidant 4,4'-dithiodimorpholine, and 10 parts by weight of plasticizer dibutyl phthalate.

[0052] At 50-70℃, nitrile rubber was added to a mixing mill and plasticized for 1-2 minutes to form a rubber sheet. Then, the uniformly mixed zinc oxide, stearic acid, sulfur masterbatch, accelerator, antioxidant, and plasticizer were added to the rubber sheet as it rotated with two rollers and mixed for 10-15 minutes. The resulting rubber compound was then vulcanized and crosslinked using a flat vulcanizing apparatus. The vulcanization time was 15 minutes, and the cooling time was 3-5 minutes. The required temperature was 160℃, and the required pressure was 15MPa. The resulting sealing material was then prepared and the material prepared in Comparative Example 1 was designated as "Comparative-1".

[0053] Comparative Example 2 The raw materials for the sealing material consist of 100 parts by weight of nitrile rubber, 10 parts by weight of zinc oxide, 5 parts by weight of stearic acid, 5 parts by weight of sulfur masterbatch, 5 parts by weight of accelerator 2,2'-dithiodibenzothiazole, 5 parts by weight of antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 5 parts by weight of antioxidant 4,4'-dithiodimorpholine, 10 parts by weight of plasticizer dibutyl phthalate, and 30 parts by weight of molybdenum disulfide.

[0054] The sealing material was prepared in the same manner as in Comparative Example 1. The material prepared in Comparative Example 2 is referred to as "Comparative-2".

[0055] Comparative Example 3 The raw materials for the sealing material consist of 100 parts by weight of nitrile rubber, 10 parts by weight of zinc oxide, 5 parts by weight of stearic acid, 5 parts by weight of sulfur masterbatch, 5 parts by weight of accelerator 2,2'-dithiodibenzothiazole, 5 parts by weight of antioxidant 2,2,4-trimethyl-1,2-dihydroquinoline polymer, 5 parts by weight of antioxidant 4,4'-dithiodimorpholine, 10 parts by weight of plasticizer dibutyl phthalate, and 30 parts by weight of N330 carbon black.

[0056] The sealing material was prepared in the same manner as in Comparative Example 1, and the material prepared in Comparative Example 3 was designated as "Comparative-3".

[0057] The sealing materials prepared in Comparative Examples 1-3 and Examples 1-7 were tested for mechanical properties, wear resistance, thermal conductivity, and sealing performance.

[0058] According to GB / T 528-2009 standard, the mechanical properties of sealing material specimens with specifications of 50 mm × 8.5 mm × 2 mm were tested. Seven specimens were tested in parallel for each group, and at least five groups were taken as average values. The results are listed in Table 1.

[0059] A 10 mm × 10 mm × 4 mm sealing material sample was selected. A 316L stainless steel ball was used as the friction pair. The test was conducted for 1 h under the conditions of friction load of 1 N, reciprocating distance of 5 mm, and friction speed of 50 mm / s. The friction coefficient of the sealing material was obtained. The wear section data (maximum depth of section and wear cross-sectional area) were tested using a 3D profilometer. The results are listed in Table 2.

[0060] A sealing material sample with dimensions of 150 mm × 100 mm × 2 mm was selected, and the thermal conductivity of the sealing material was tested. The results are listed in Table 3.

[0061] According to the GB1038-2000 standard, a sealing material specimen with a specification of 70 mm × 70 mm × 0.5 mm was selected to test the permeability of nitrogen and oxygen in the sealing material.

[0062] Table 1 Mechanical properties of sealing materials prepared in Comparative Examples 1-3 and Examples 1-7

[0063] The three comparative examples show that the addition of both carbon black and molybdenum disulfide fillers can significantly improve the mechanical strength of the composite material. Carbon black, which provides physical cross-linking points, has a more significant reinforcing effect on the material (the strength can be increased from 3.09 MPa to a maximum of 13.07 MPa). However, the addition of either of the two fillers alone will lead to a decrease in the elongation at break of the material, proving that the interfacial compatibility between the nitrile rubber matrix and the filler is poor. That is, the junction between the matrix and the filler is prone to become a stress concentration point, which in turn leads to a decrease in flexibility. Examples 1 and 2 used unmodified carbon black and molybdenum disulfide. The material strength and elongation at break were not significantly different, but they continued to decrease, indicating that the compatibility of the two fillers was also poor under unmodified conditions. Examples 3, 4, and 5 used three coupling agents, KH550 (amino type), KH560 (epoxy type), and KH570 (methacryloyloxy type), respectively, to modify molybdenum disulfide. The test results showed that molybdenum disulfide modified with KH560 containing epoxy groups had the best reinforcing effect on the material, significantly improving the material's strength (strength increased from 6.53 Pa to 10.67 MPa) and toughness (elongation at break increased from 753% to 1102%). KH550 had the second best effect, while KH570 had the most limited improvement effect. Based on the preferred KH560 modified molybdenum disulfide, Examples 6 and 7 further varied the ratio of carbon black and molybdenum disulfide as reinforcing fillers. Test results revealed a synergistic reinforcement mechanism between the two fillers: carbon black primarily enhances the tensile strength and modulus of the composite material (reinforcing phase), while the modified molybdenum disulfide significantly improves the tear resistance and elongation at break (toughening phase). By adjusting the ratio of the two, a gradient design from "rigidity" to "toughness" can be achieved, resulting in a composite material with optimal overall performance.

[0064] Table 2. Wear resistance of the sealing materials prepared in Comparative Examples 1-3 and Examples 1-7 under dry friction conditions.

[0065] As shown in Table 2, in the comparative examples, the addition of both carbon black and molybdenum disulfide improved the wear resistance of the materials under dry friction conditions, with molybdenum disulfide showing a more significant improvement, reducing the friction coefficient from 2.9 to 0.9. Furthermore, compared to Examples 1-2, the sealing materials prepared using modified molybdenum disulfide as filler in Examples 3-7 of this invention exhibited lower friction coefficients, smaller maximum wear depths, and smaller wear cross-sectional areas under dry friction conditions, demonstrating excellent wear resistance. In particular, Examples 4, 6, and 7, which used KH560 modified molybdenum disulfide, had friction coefficients of 1.5, 1.4, and 1.8, respectively; maximum wear depths of 209 μm, 222 μm, and 192 μm, respectively; and wear cross-sectional areas of 203,300 μm, respectively. 2 227195μm 2and 167348 μm 2 All of them are significantly better than the comparative examples and Examples 1 and 2 using unmodified molybdenum disulfide, as well as Examples 3 (KH550) and 5 (KH570) using other modifiers, indicating that the material of the present invention significantly improves wear resistance while maintaining good mechanical properties, and is suitable for sealing applications with high wear resistance requirements.

[0066] Table 3 Thermal conductivity (W) of the sealing materials prepared in Comparative Examples 1-3 and Examples 1-7 . m -1. K -1 )

[0067] As can be seen from the data in Table 3, the thermal conductivity of Comparative Example 2 (0.3932 W) is... . m -1. K -1 The thermal conductivity was significantly higher than that of Comparative Example 3 (0.0.2597 W). . m -1. K -1 This indicates that molybdenum disulfide, with its lamellar structure, is more conducive to forming a continuous thermally conductive network within the nitrile rubber matrix, thus conducting heat more effectively than particulate carbon black. Compared to Comparative Example 1, the sealing material prepared in this invention exhibits higher thermal conductivity, with the composite materials prepared in Examples 3, 4, and 5 showing thermal conductivity of 0.3278 W. . m -1. K -1 0.3294 W . m -1. K -1 0.3266W . m -1. K -1 This indicates that KH560-modified molybdenum disulfide has the best compatibility with the nitrile rubber matrix, enabling the formation of a high-quality thermally conductive network. Based on the preferred KH560-modified molybdenum disulfide, Example 6 achieved a thermal conductivity of 0.4102 W by increasing the amount of molybdenum disulfide filler. . m -1. K -1 The material of this invention is significantly superior to that of the comparative examples and other embodiments. Therefore, while maintaining good mechanical properties and wear resistance, the material of this invention also has excellent thermal conductivity, which can promptly dissipate heat generated during the sealing process or conducted externally, reduce the thermal aging rate of the sealing material, and extend the service life of the material.

[0068] Table 4. Sealing performance of the sealing materials prepared in Comparative Examples 1-3 and Examples 1-7

[0069] As shown in Table 4, compared with Comparative Example 1, the addition of carbon black or molybdenum disulfide in Comparative Example 2 or Comparative Example 3 can improve the material's sealing performance against nitrogen and oxygen, with molybdenum disulfide showing a more significant improvement. The N2 permeability coefficient increased from 1.24 × 10⁻⁶. -13 (cm 3 ·cm) / (cm 2 The concentration of s·Pa decreased to 7.46 × 10 -14 (cm 3 ·cm) / (cm 2 The air permeability coefficient of O2 (·s·Pa) is 5.16×10 -13 (cm 3 ·cm) / (cm 2 The concentration of s·Pa decreased to 2.91 × 10⁻⁶. -13 (cm 3 ·cm) / (cm 2 The gas permeability of molybdenum disulfide (·s·Pa) is significantly improved compared to particulate carbon black because its layered structure creates a "maze effect" in the matrix, effectively extending the diffusion path of gas molecules. Compared to the comparative examples and Examples 1 and 2 using unmodified molybdenum disulfide, the sealing materials prepared using modified molybdenum disulfide in Examples 3-7 of this invention exhibit lower nitrogen and oxygen permeability coefficients, demonstrating excellent gas permeability. In particular, Example 6, which uses a high amount of KH560 modified molybdenum disulfide, has an N2 permeability coefficient of 2.02 × 10⁻⁶. -14 (cm 3 ·cm) / (cm 2 The O2 permeability coefficient is 7.82 × 10⁻⁶ Pa·s. -14 (cm 3 ·cm) / (cm 2 The concentration of molybdenum disulfide (·s·Pa) was reduced by more than an order of magnitude compared to the comparative example, further demonstrating the improvement in material performance brought about by KH560-modified molybdenum disulfide. Therefore, the material of this invention maintains good overall performance while also possessing excellent airtightness, making it suitable for sealing applications with stringent gas barrier requirements.

[0070] The embodiments of the present invention have been described above by way of example. However, the scope of protection of the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A nitrile rubber sealing material, characterized in that, Based on parts by weight, it comprises the following components: 100 parts of nitrile rubber matrix, 2-10 parts zinc oxide Stearic acid 0.5-5 parts, Sulfur masterbatch 0.5-5 parts, Accelerator 0.5-5 parts, Anti-aging agent 2-10 parts, Plasticizer 1-10 parts, 10-30 parts carbon black 5-30 parts of molybdenum disulfide or silane coupling agent modified molybdenum disulfide.

2. The nitrile rubber sealing material according to claim 1, characterized in that, The accelerator is 2,2'-dithiodibenzothiazole.

3. The nitrile rubber sealing material according to claim 1, characterized in that, The antioxidant is at least one of 2,2,4-trimethyl-1,2-dihydroquinoline polymer and 4,4'-dithiodimorpholine.

4. The nitrile rubber sealing material according to claim 1, characterized in that, The plasticizer is dibutyl phthalate.

5. The nitrile rubber sealing material according to claim 1, characterized in that, The carbon black is at least one of N330 and N550 types.

6. The nitrile rubber sealing material according to claim 1, characterized in that, The acrylonitrile content in the nitrile rubber matrix is ​​25~35 wt%.

7. The nitrile rubber sealing material according to claim 1, characterized in that, The silane coupling agent is selected from at least one of γ-aminopropyltriethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, and γ-methacryloyloxypropyltrimethoxysilane.

8. A method for preparing the sealing material according to any one of claims 1-7, characterized in that, The method is as follows: The raw materials are mixed and molded to obtain a compound rubber; the compound rubber is vulcanized to prepare the sealing material.

9. The preparation method according to claim 8, characterized in that, The vulcanization temperature is 160~170℃; the vulcanization pressure is 10-20MPa; and the vulcanization time is 15~35min.

10. The application of the sealing material according to any one of claims 1-7 in the preparation of any one of hydraulic seals, piston seals, electronic device seals, and high-pressure oil-gas sealing materials.

Images