High temperature resistant nitrile rubber material and preparation method thereof

Abstract

The application relates to the technical field of rubber, and discloses a high-temperature-resistant nitrile rubber material and a preparation method thereof. The high-temperature-resistant nitrile rubber comprises the following components in parts by weight: 75-95 parts of nitrile rubber, 18-24 parts of fluorine rubber, 3-6 parts of ethylene propylene acrylate elastomer, 15-25 parts of a filler, 2-4 parts of an antioxidant, 1-2 parts of a lubricant, 1-1.4 parts of a plasticizer, 1.4-1.8 parts of an accelerator, 1-2 parts of a coupling agent, 8-16 parts of a flame retardant, 1.2-2 parts of a vulcanizing agent and 1-2 parts of zinc oxide; the filler comprises basalt fibers, graphene oxide and lanthanum-doped silicon dioxide. The technical scheme can solve the problem of insufficient high-temperature resistance of the nitrile rubber in the prior art.

Description

Technical Field

[0001] This invention relates to the field of rubber technology, specifically to a high-temperature resistant nitrile rubber material and its preparation method. Background Technology

[0002] Nitrile rubber (NBR) is widely used in various fields due to its excellent oil resistance, abrasion resistance, and corrosion resistance. However, the presence of numerous unsaturated double bonds in its molecular chain structure and weak intermolecular forces result in poor high-temperature resistance. At excessively high temperatures, the molecular chains are prone to thermal oxidative degradation, leading to hardening, brittleness, and loss of elasticity in rubber products. This limits its application in high-temperature environments such as engine high-temperature component sealing, deep well equipment in oil fields, and high-temperature oil-resistant components in aerospace. Therefore, it is necessary to develop a high-temperature resistant NBR material to address this issue. Summary of the Invention

[0003] This invention proposes a high-temperature resistant nitrile rubber material and its preparation method, which solves the problem of insufficient high-temperature resistance of nitrile rubber in related technologies.

[0004] The technical solution of the present invention is as follows: This invention proposes a high-temperature resistant nitrile rubber, comprising the following components in parts by weight: 75-95 parts nitrile rubber, 18-24 parts fluororubber, 3-6 parts ethylene acrylate elastomer, 15-25 parts filler, 2-4 parts antioxidant, 1-2 parts lubricant, 1-1.4 parts plasticizer, 1.4-1.8 parts accelerator, 1-2 parts coupling agent, 8-16 parts flame retardant, 1.2-2 parts vulcanizing agent, and 1-2 parts zinc oxide; The filler includes basalt fiber, graphene oxide, and lanthanum-doped silicon dioxide.

[0005] As a further technical solution, the mass ratio of the basalt fiber, graphene oxide, and lanthanum-doped silicon dioxide is 4:0.8:4~5.

[0006] In this invention, the mass ratio of basalt fiber, graphene oxide, and lanthanum-doped silicon dioxide is limited to 4:0.8:4~5 to further improve the high-temperature resistance of nitrile rubber. When there is too much lanthanum doping with cerium dioxide, the risk of agglomeration increases; when there is too little, its thermal barrier function cannot be fully utilized, which will reduce the high-temperature resistance of nitrile rubber.

[0007] As a further technical solution, the method for preparing the lanthanum-doped silicon dioxide includes the following steps: Water, anhydrous sodium acetate, and lanthanum acetate hydrate were mixed to obtain solution A; Silica was dispersed in water to obtain a silica suspension; The silica suspension was added to solution A, followed by ultrasonication, hydrothermal reaction, cooling, centrifugation, washing, and drying to obtain lanthanum-doped silica.

[0008] As a further technical solution, the mass ratio of anhydrous sodium acetate, lanthanum acetate hydrate, and water is 0.41:0.25:9.5~11.

[0009] As a further technical solution, the mass ratio of silicon dioxide to water is 0.05:9~11.

[0010] As a further technical solution, the mass ratio of lanthanum acetate hydrate to silicon dioxide is 5:1.

[0011] As a further technical solution, the ultrasound duration is 10-15 minutes and the power is 80-120W.

[0012] As a further technical solution, the temperature of the hydrothermal reaction is 170~190℃ and the time is 11~13h.

[0013] As a further technical solution, the centrifugation rate is 7500~8500 rpm and the time is 4~6 min.

[0014] As a further technical solution, the washing process involves rinsing with methanol 2-3 times.

[0015] As a further technical solution, the drying temperature is 70~100℃ and the time is 4~7h.

[0016] As a further technical solution, the fluororubber includes dimer fluororubber, trimer fluororubber and fluorosilicone rubber in a mass ratio of 4.5:3:2.5~3.5.

[0017] In this invention, dimer fluororubber, trimer fluororubber, and fluorosilicone rubber are used together, further improving the high-temperature resistance of nitrile rubber. Fluororubber itself has excellent high-temperature resistance, and dimer fluororubber and trimer fluororubber are interspersed in nitrile rubber to form a tight structure. The silicon-oxygen bonds in fluorosilicone rubber can absorb some heat, further buffering the heat, thereby obtaining nitrile rubber with excellent high-temperature resistance.

[0018] As a further technical solution, the antioxidant includes one or both of antioxidant RD and antioxidant 4010NA.

[0019] As a further technical solution, the lubricant includes one or both of stearic acid and butyl stearate.

[0020] As a further technical solution, the plasticizer includes one or both of trioctyl trimellitate and tricresyl phosphate.

[0021] As a further technical solution, the accelerator includes one or both of accelerator CZ and accelerator TMTD.

[0022] As a further technical solution, the coupling agent includes one or both of silane coupling agents and titanate coupling agents.

[0023] As a further technical solution, the flame retardant includes one or both of aluminum hydroxide and magnesium hydroxide.

[0024] As a further technical solution, the vulcanizing agent includes vulcanizing agent DCP.

[0025] This invention also proposes a method for preparing a high-temperature resistant nitrile rubber material, comprising the following steps: Nitrile rubber, fluororubber, ethylene acrylate elastomer, filler, antioxidant, lubricant, plasticizer, accelerator, coupling agent, and flame retardant are mixed and then vulcanized with vulcanizing agent and zinc oxide to obtain high-temperature resistant nitrile rubber material.

[0026] The working principle and beneficial effects of this invention are as follows: In this invention, basalt fiber, graphene oxide, and lanthanum-doped silica are used together to improve the high-temperature resistance of nitrile rubber. The layered graphene oxide has high thermal conductivity, which quickly disperses heat and avoids heat accumulation. The linear basalt fiber forms a network structure to further disperse heat and inhibit the thermal motion of rubber molecules in the matrix, thereby improving the thermal stability of the rubber. Lanthanum-doped silica is filled between the linear basalt fiber and the layered graphene oxide. Its hollow structure can act as a thermal barrier to slow down the heat transfer rate. The combined use of these three materials significantly improves the high-temperature resistance of nitrile rubber. Detailed Implementation

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

[0028] In the following embodiments and comparative examples, Nitrile rubber: Model GM50, manufactured by Jingjiang Guangsheng Rubber & Plastic Materials Factory; Dimeric fluororubber: Model number FC 2230, manufactured by 3M Company; Trimeric fluororubber: model number FPO 3730, manufacturer is 3M; Fluorosilicone rubber: Model DS412, manufactured by Shandong Dongyue Polymer Materials Co., Ltd. Ethylene acrylate elastomer: Model: Vamac Ultra HT; Basalt fiber: monofilament diameter is 5μm, length is 6mm; Graphene oxide: Model name: lgshimo, manufacturer: Henan Wanying Refractory Materials Technology Co., Ltd. Silica: Particle size 300nm.

[0029] Example 1 A high-temperature resistant nitrile rubber comprises the following components in parts by weight: 75 parts nitrile rubber, 18 parts fluororubber, 3 parts ethylene acrylate elastomer, 15 parts filler, 2 parts antioxidant RD, 1 part stearic acid, 1 part trioctyl trimellitate, 1.4 parts accelerator CZ, 1 part silane coupling agent KH550, 5 parts aluminum hydroxide, 3 parts magnesium hydroxide, 1.2 parts vulcanizing agent DCP, and 1 part zinc oxide; The filler is basalt fiber, graphene oxide and lanthanum-doped silicon dioxide in a mass ratio of 4:0.8:3; Fluororubber is a dimer fluororubber and a trimer fluororubber with a mass ratio of 4.5:3; The method for preparing lanthanum-doped silicon dioxide includes the following steps: Water, anhydrous sodium acetate, and lanthanum acetate hydrate were mixed (the mass ratio of anhydrous sodium acetate, lanthanum acetate hydrate, and water was 0.41:0.25:9.5) to obtain solution A; Silica is dispersed in water (the mass ratio of silica to water is 0.05:9) to obtain a silica suspension; The silica suspension was added to solution A (the mass ratio of lanthanum acetate hydrate to silica was 5:1), sonicated at 120W for 10 min, and then hydrothermally reacted at 170℃ for 13 h. After cooling to room temperature, it was centrifuged at 7500 rpm for 6 min, washed twice with methanol, and finally dried at 70℃ for 7 h to obtain lanthanum-doped silica. A method for preparing a high-temperature resistant nitrile rubber material includes the following steps: Nitrile rubber, fluororubber, ethylene acrylate elastomer, filler, antioxidant RD, stearic acid, trioctyl trimellitate, accelerator CZ, silane coupling agent KH550, aluminum hydroxide, and magnesium hydroxide are mixed together, then vulcanizing agent DCP and zinc oxide are added, and the mixture is further mixed and vulcanized to obtain a high-temperature resistant nitrile rubber material.

[0030] Example 2 A high-temperature resistant nitrile rubber comprises the following components in parts by weight: 95 parts nitrile rubber, 24 parts fluororubber, 6 parts ethylene acrylate elastomer, 25 parts filler, 4 parts antioxidant 4010NA, 2 parts butyl stearate, 1.4 parts tricresyl phosphate, 1 part accelerator CZ, 0.8 parts accelerator TMTD, 1.8 parts silane coupling agent KH550, 0.2 parts titanate coupling agent NDZ-101, 10 parts aluminum hydroxide, 6 parts magnesium hydroxide, 2 parts vulcanizing agent DCP, and 1 part zinc oxide; The filler is basalt fiber, graphene oxide and lanthanum-doped silicon dioxide in a mass ratio of 4:0.8:3; Fluororubber is a dimer fluororubber and a trimer fluororubber with a mass ratio of 4.5:3; The method for preparing lanthanum-doped silicon dioxide includes the following steps: Water, anhydrous sodium acetate, and lanthanum acetate hydrate were mixed (the mass ratio of anhydrous sodium acetate, lanthanum acetate hydrate, and water was 0.41:0.25:11) to obtain solution A; Silica is dispersed in water (the mass ratio of silica to water is 0.05:11) to obtain a silica suspension; The silica suspension was added to solution A (the mass ratio of lanthanum acetate hydrate to silica was 5:1), sonicated at 80W for 15 min, and then hydrothermally reacted at 190℃ for 11 h. After cooling to room temperature, it was centrifuged at 8500 rpm for 4 min, washed 3 times with methanol, and finally dried at 100℃ for 4 h to obtain lanthanum-doped silica. A method for preparing a high-temperature resistant nitrile rubber material includes the following steps: Nitrile rubber, fluororubber, ethylene acrylate elastomer, filler, antioxidant 4010NA, butyl stearate, tricresyl phosphate, accelerator CZ, accelerator TMTD, silane coupling agent KH550, titanate coupling agent NDZ-101, aluminum hydroxide, and magnesium hydroxide are mixed together. Then, vulcanizing agent DCP and zinc oxide are added, and the mixture is further mixed and vulcanized to obtain a high-temperature resistant nitrile rubber material.

[0031] Example 3 A high-temperature resistant nitrile rubber comprises the following components in parts by weight: 85 parts nitrile rubber, 21 parts fluororubber, 5 parts ethylene acrylate elastomer, 20 parts filler, 3.2 parts antioxidant RD, 1.5 parts stearic acid, 1.2 parts trioctyl trimellitate, 0.8 parts accelerator CZ, 0.4 parts accelerator TMTD, 1.2 parts silane coupling agent KH550, 0.3 parts titanate coupling agent NDZ-101, 8 parts aluminum hydroxide, 4 parts magnesium hydroxide, 1.6 parts vulcanizing agent DCP, and 1.5 parts zinc oxide; The filler is basalt fiber, graphene oxide and lanthanum-doped silicon dioxide in a mass ratio of 4:0.8:3; Fluororubber is a dimer fluororubber and a trimer fluororubber with a mass ratio of 4.5:3; The method for preparing lanthanum-doped silicon dioxide includes the following steps: Water, anhydrous sodium acetate, and lanthanum acetate hydrate were mixed (the mass ratio of anhydrous sodium acetate, lanthanum acetate hydrate, and water was 0.41:0.25:10) to obtain solution A; Silica is dispersed in water (the mass ratio of silica to water is 0.05:10) to obtain a silica suspension; The silica suspension was added to solution A (the mass ratio of lanthanum acetate hydrate to silica was 5:1), sonicated at 100W for 13 min, and then hydrothermally reacted at 180℃ for 12 h. After cooling to room temperature, it was centrifuged at 8000 rpm for 5 min, washed 3 times with methanol, and finally dried at 80℃ for 6 h to obtain lanthanum-doped silica. A method for preparing a high-temperature resistant nitrile rubber material includes the following steps: Nitrile rubber, fluororubber, ethylene acrylate elastomer, filler, antioxidant RD, stearic acid, trioctyl trimellitate, accelerator CZ, accelerator TMTD, silane coupling agent KH550, titanate coupling agent NDZ-101, aluminum hydroxide, and magnesium hydroxide are mixed together. Then, vulcanizing agent DCP and zinc oxide are added, and the mixture is further mixed and vulcanized to obtain a high-temperature resistant nitrile rubber material.

[0032] Example 4 The only difference between this embodiment and Embodiment 3 is that the filler is basalt fiber, graphene oxide, and lanthanum-doped silicon dioxide in a mass ratio of 4:0.8:4.

[0033] Example 5 The only difference between this embodiment and Embodiment 3 is that the filler is basalt fiber, graphene oxide, and lanthanum-doped silicon dioxide in a mass ratio of 4:0.8:5.

[0034] Example 6 The only difference between this embodiment and Embodiment 3 is that the filler is basalt fiber, graphene oxide, and lanthanum-doped silicon dioxide in a mass ratio of 4:0.8:6.

[0035] Example 7 The only difference between this embodiment and Embodiment 4 is that the fluororubber is a dimer fluororubber and fluorosilicone rubber with a mass ratio of 4.5:2.5.

[0036] Example 8 The only difference between this embodiment and Embodiment 4 is that the fluororubber is a trimer of fluororubber and fluorosilicone rubber with a mass ratio of 3:2.5.

[0037] Example 9 The only difference between this embodiment and Embodiment 4 is that the fluororubber is a dimer fluororubber, a trimer fluororubber, and a fluorosilicone rubber with a mass ratio of 4.5:3:2.5.

[0038] Example 10 The only difference between this embodiment and Embodiment 4 is that the fluororubber is a dimer fluororubber, a trimer fluororubber, and a fluorosilicone rubber in a mass ratio of 4.5:3:3.

[0039] Example 11 The only difference between this embodiment and Embodiment 4 is that the fluororubber is a dimer fluororubber, a trimer fluororubber, and a fluorosilicone rubber with a mass ratio of 4.5:3:3.5.

[0040] Comparative Example 1 The only difference between this comparative example and Example 3 is that the filler is basalt fiber, graphene oxide and silicon dioxide in a mass ratio of 4:0.8:3.

[0041] Comparative Example 2 The only difference between this comparative example and Example 3 is that the filler is basalt fiber and graphene oxide in a mass ratio of 4:0.8.

[0042] Comparative Example 3 The only difference between this comparative example and Example 3 is that the filler is basalt fiber and lanthanum-doped silicon dioxide in a mass ratio of 4:3.

[0043] Comparative Example 4 The only difference between this comparative example and Example 3 is that the filler is graphene oxide and lanthanum-doped silicon dioxide in a mass ratio of 0.8:3.

[0044] The high-temperature resistant nitrile rubbers obtained in Examples 1-11 and Comparative Examples 1-4 were tested according to the following method: 1. Tensile strength: Tested according to GB / T 528-2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber", with dumbbell-shaped type 1 specimens selected. 2. Heat resistance test: According to GB / T 3512-2014 "Accelerated aging and heat resistance test of vulcanized rubber or thermoplastic rubber in hot air", the aging temperature is 140℃ and the time is 168h; Tensile strength retention rate = (Tensile strength after heat resistance test treatment / Tensile strength before treatment) × 100%; The test results are shown in Table 1 below: Table 1. Performance test results of high-temperature resistant nitrile rubbers prepared in Examples 1-11 and Comparative Examples 1-4

[0045] 1. Compared with Comparative Examples 1 to 4, the nitrile rubber materials prepared in Examples 1 to 11 showed a significantly higher tensile strength retention rate after heat resistance test treatment than those in Comparative Examples 1 to 4. This indicates that the combined use of basalt fiber, graphene oxide and lanthanum-doped silica can improve the high temperature resistance of nitrile rubber.

[0046] 2. Compared with Examples 3 to 6, the nitrile rubber materials prepared in Examples 4 to 5 have a higher tensile strength retention rate after heat resistance test treatment than those in Examples 3 and 6. This indicates that further limiting the mass ratio of basalt fiber, graphene oxide and lanthanum-doped silicon dioxide to 4:0.8:4~5 can further improve the high temperature resistance of nitrile rubber.

[0047] 3. The nitrile rubber materials prepared in Examples 4, 7-11, and 9-11 retained a tensile strength of over 99% after heat resistance testing, which is higher than that in Examples 4 and 7-8. This indicates that the compounding of dimer fluororubber, trimer fluororubber, and fluorosilicone rubber can improve the high-temperature resistance of nitrile rubber.

[0048] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-temperature resistant nitrile rubber, comprising the following components in parts by weight: 75-95 parts nitrile rubber, 18-24 parts fluororubber, 3-6 parts ethylene acrylate elastomer, 15-25 parts filler, 2-4 parts antioxidant, 1-2 parts lubricant, 1-1.4 parts plasticizer, 1.4-1.8 parts accelerator, 1-2 parts coupling agent, 8-16 parts flame retardant, 1.2-2 parts vulcanizing agent, and 1-2 parts zinc oxide; The filler includes basalt fiber, graphene oxide, and lanthanum-doped silicon dioxide.

2. The high-temperature resistant nitrile rubber according to claim 1, characterized in that, The mass ratio of basalt fiber, graphene oxide, and lanthanum-doped silicon dioxide is 4:0.8:4~5.

3. The high-temperature resistant nitrile rubber according to claim 1, characterized in that, The method for preparing the lanthanum-doped silicon dioxide includes the following steps: Water, anhydrous sodium acetate, and lanthanum acetate hydrate were mixed to obtain solution A; Silica was dispersed in water to obtain a silica suspension; The silica suspension was added to solution A, followed by ultrasonication, hydrothermal reaction, cooling, centrifugation, washing, and drying to obtain lanthanum-doped silica.

4. The high-temperature resistant nitrile rubber according to claim 3, characterized in that, The mass ratio of anhydrous sodium acetate, lanthanum acetate hydrate, and water is 0.41:0.25:9.5~11; The mass ratio of silicon dioxide to water is 0.05:9~11; The mass ratio of lanthanum acetate hydrate to silicon dioxide is 5:

1. The hydrothermal reaction is carried out at a temperature of 170~190℃ for 11~13 hours.

5. The high-temperature resistant nitrile rubber according to claim 1, characterized in that, The fluororubber includes dimer fluororubber, trimer fluororubber, and fluorosilicone rubber in a mass ratio of 4.5:3:2.5~3.

5.

6. The high-temperature resistant nitrile rubber according to claim 1, characterized in that, The antioxidant includes one or both of antioxidant RD and antioxidant 4010NA; The lubricant includes one or both of stearic acid and butyl stearate.

7. The high-temperature resistant nitrile rubber according to claim 1, characterized in that, The plasticizer includes one or both of trioctyl trimellitate and tricresyl phosphate; The accelerator includes one or both of accelerator CZ and accelerator TMTD.

8. The high-temperature resistant nitrile rubber according to claim 1, characterized in that, The coupling agent includes one or both of silane coupling agents and titanate coupling agents; The flame retardant includes one or both of aluminum hydroxide and magnesium hydroxide.

9. The high-temperature resistant nitrile rubber according to claim 1, characterized in that, The vulcanizing agent includes vulcanizing agent DCP.

10. A method for preparing a high-temperature resistant nitrile rubber material, used to prepare the high-temperature resistant nitrile rubber material according to any one of claims 1 to 9, characterized in that, Includes the following steps: Nitrile rubber, fluororubber, ethylene acrylate elastomer, filler, antioxidant, lubricant, plasticizer, accelerator, coupling agent, and flame retardant are mixed and then vulcanized with vulcanizing agent and zinc oxide to obtain high-temperature resistant nitrile rubber material.

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