High / low-temperature-resistant wear-resistant tear-resistant fluorosilicone rubber compound and preparation method thereof

Abstract

The invention relates to a high / low-temperature-resistant wear-resistant tear-resistant fluorosilicone rubber compound and a preparation method thereof, and belongs to the technical field of special rubber materials, the high / low-temperature-resistant wear-resistant tear-resistant fluorosilicone rubber compound comprises the following components: raw fluorosilicone rubber, a reactive liquid rubber compatibilizer, a reinforcing filler, a tear-resistant aid, a high-temperature-resistant aid, a vulcanizing agent, an accelerant, an anti-aging agent and an anti-attrition filler, the provided reaction type liquid rubber compatibilizer contains vinyl carboxyl liquid fluorosilicone rubber, the tear-resistant auxiliary agent contains zinc polymethacrylate, the high-temperature auxiliary agent contains vinyl fluorosilane modified carbon nanotubes, and the anti-friction filler contains molybdenum disulfide and layered nano zirconium phosphate which are treated by oxygen plasma. The high and low temperature resistance stability, oil resistance, wear resistance and tear strength of the fluorosilicone rubber are synergistically improved by regulating and controlling the multi-cross-linked network structure of the fluorosilicone rubber, strengthening the interface action of the rubber and the filler and optimizing the composite vulcanization system, meanwhile, structuralization of a rubber compound is prevented by optimizing the preparation process, and the requirement for adaptability to severe working conditions is met.

Description

Technical Field

[0001] The present invention relates to the technical field of special rubber materials, and in particular to a fluorosilicone rubber compound with high and low temperature resistance, wear resistance and tear resistance, and a preparation method thereof. Background Art

[0002] Fluorosilicone rubber is a high-performance elastomer material, which combines the high and low temperature resistance characteristics of silicone rubber and the oil and solvent resistance advantages of fluororubber, and has good application prospects in the fields of new energy vehicles, high-end hydraulic equipment, aerospace and petrochemical industries.

[0003] However, fluorosilicone rubber still has defects such as rapid attenuation of mechanical properties, poor tear strength and unsatisfactory wear resistance under harsh high and low temperature, high-speed and high-torque working conditions, which limit its application in high-end sealing parts. Chinese invention patent CN106867258A uses silicone rubber, fluororubber and vinylidene fluoride ether rubber for mixing, which improves the temperature resistance and oil resistance of the compound to a certain extent, but the compatibility between the rubber components is poor, and phase separation is likely to occur, and the wear resistance and tear resistance still cannot meet the increasing application requirements. Chinese invention patent CN119081419A uses silane coupling agent and maleic anhydride as interfacial modifiers and mixes them with modified fluorosilicone rubber, etc. Although the tensile strength and tear resistance of fluorosilicone rubber are greatly improved, the synergistic optimization between low-temperature embrittlement performance and high-temperature wear resistance is not involved.

[0004] In view of the above related technologies, the present invention aims to provide a fluorosilicone rubber compound with high and low temperature resistance, wear resistance and tear resistance. By constructing a multi-molecular chain crosslinking network of fluorosilicone rubber, interfacial modification of fillers and optimization of the composite vulcanization system, the high and low temperature stability, dynamic wear resistance and tear strength of fluorosilicone rubber are synergistically improved. At the same time, the risk of the compound becoming structured is reduced by optimizing the preparation process. This technical breakthrough will effectively solve the urgent need for high-performance sealing materials to adapt to extreme working conditions in the fields of new energy vehicles, aerospace and other fields. Summary of the Invention

[0005] In order to improve the high and low temperature resistance, oil resistance, tear resistance, processing performance and wear resistance of fluorosilicone rubber, the present application provides a fluorosilicone rubber compound with high and low temperature resistance, wear resistance and tear resistance, and a preparation method thereof.

[0006] The fluorosilicone rubber compound with high and low temperature resistance, wear resistance and tear resistance provided by the present invention and its preparation method adopt the following technical solutions:

[0007] In the first aspect, the present invention provides a fluorosilicone rubber compound with high and low temperature resistance, wear resistance and tear resistance, comprising the following raw materials in parts by mass:

[0008] Raw fluorosilicone rubber: 100 parts;

[0009] Reactive liquid rubber compatibilizer: 2 - 5 parts;

[0010] Reinforcing filler: 20 - 40 parts;

[0011] Tear resistance aid: 2 - 5 parts;

[0012] High temperature resistant aid: 1 - 3 parts;

[0013] Vulcanizing agent: 2 - 4 parts;

[0014] Accelerator: 1 - 3 parts;

[0015] Antioxidant: 2 - 4 parts;

[0016] Anti - friction filler: 10 - 20 parts.

[0017] As a preferred technical solution of the present invention, the vinyl content of the fluorosilicone rubber raw rubber is 0.05% - 0.5%, and the number - average molecular weight is 200,000 - 600,000.

[0018] As a preferred technical solution of the present invention, the reactive liquid rubber compatibilizer is at least one of vinyl carboxyl liquid silicone rubber, vinyl phenol hydroxyl liquid silicone rubber, vinyl urethane liquid silicone rubber, vinyl carboxyl liquid fluorosilicone rubber.

[0019] As a preferred technical solution of the present invention, the reinforcing filler is at least one of fluorosilane - modified silica, high - abrasion furnace black, silica powder, potassium titanate whiskers.

[0020] As a preferred technical solution of the present invention, the tear resistance aid is at least one of zinc polymethacrylate, bis - [γ - (triethoxysilyl) propyl] tetrasulfide, glass microspheres.

[0021] As a preferred technical solution of the present invention, the high temperature resistant aid is at least one of nano - cerium oxide, nano - lanthanum oxide, fluorosilane - modified carbon nanotubes.

[0022] As a preferred technical solution of the present invention, the vulcanizing agent is at least one of dibenzoyl peroxide, di - isopropylbenzene peroxide, tert - butyl peroxybenzoate, 2,5 - dimethyl - 2,5 - bis(tert - butylperoxy) hexane.

[0023] As a preferred technical solution of the present invention, the accelerator is at least one of benzyltriphenylphosphonium chloride, triallyl isocyanurate, bisphenol - AF, magnesium oxide.

[0024] As a preferred technical solution of the present invention, the antioxidant is at least one of N,N'-di(β - naphthyl) - p - phenylenediamine, dibenzyl hydroquinone ether, N - isopropyl - N'-phenyl - p - phenylenediamine, zinc 2 - mercaptobenzimidazole.

[0025] As a preferred technical solution of the present invention, the anti-friction filler is at least one of molybdenum disulfide, graphite, layered nanozirconium phosphate, and polytetrafluoroethylene fine powder treated by oxygen plasma.

[0026] In a second aspect, the present invention provides a method for preparing a high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber masterbatch, comprising the following steps:

[0027] S1. Put fluorosilicone rubber raw rubber, reactive liquid rubber compatibilizer, reinforcing filler, anti-tear aid, high temperature resistant aid, anti-aging agent, and anti-friction filler into a mixer in proportion, control the temperature at 80-100 °C, mix for 10-15 min and then take out and cool to room temperature to obtain a fluorosilicone rubber premix;

[0028] S2. Add vulcanizing agent and accelerator to the fluorosilicone rubber premix described in S1, mix by making a triangular package through a two-roll mill at room temperature for 6-8 min, the roll spacing of the mill is 0.5-2 mm, and after mixing, quickly blow with cold air to cool the masterbatch to room temperature, and store it in an environment below 28 °C and air humidity <70%.

[0029] S3. Use a flat vulcanizer to vulcanize the coagulated rubber in S2 under the conditions of a temperature of 160-175 °C and a pressure of 10-20 MPa for 6-10 min, and then carry out secondary vulcanization in a blast oven at 200 °C for 2-3 h to obtain a high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber masterbatch.

[0030] The beneficial effects of the present invention are as follows:

[0031] (1) The high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber masterbatch provided by the present invention has the advantages of high and low temperature resistance, oil resistance, tear resistance, good processing performance, low friction coefficient, and outstanding wear resistance, and can meet the performance requirements of rubber seals for high-speed and high-torque power motors of new energy vehicles in harsh high and low temperature environments, greatly improving the safety, stability, power performance and service life of the power motors of new energy vehicles.

[0032] (2) The formula provided by the present invention does not contain small molecule compatibilizers, coupling agents and plasticizers, but uses a reactive liquid rubber compatibilizer, which not only overcomes the defects of easy degradation or migration loss of small molecule compatibilizers or coupling agents, but also improves the service performance of fluorosilicone rubber in low temperature environments through plasticization and compatibilization effects. At the same time, by regulating the multiple cross-linked network structure of fluorosilicone rubber and strengthening the interface interaction between rubber and filler, the high and low temperature stability, oil resistance, wear resistance and tear strength of fluorosilicone rubber are synergistically improved.

[0033] (3) The formulated ingredients provided by the present invention include high-temperature resistant additives such as nano-cerium oxide, nano-lanthanum oxide, and fluorosilane-modified carbon nanotubes. These additives can not only improve the antioxidant performance and mechanical stability of fluorosilicone rubber at high temperatures but also have a good nano-reinforcement effect on the rubber matrix, further enhancing its tear resistance. Detailed Embodiments

[0034] Unless otherwise defined, the technical terms and scientific terms used in this application shall have the same meanings as those commonly understood by those skilled in the relevant technical fields. The terms used in this application are only for describing specific embodiments and are not intended to limit this application. It should be understood that when used in this specification and the appended claims, the terms "include" and "comprise" indicate the presence of the described features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0035] To further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following, in combination with embodiments, details the specific embodiments, structures, features, and their effects according to the present invention as follows.

[0036] Example 1

[0037] A preparation method of a fluorosilicone rubber masterbatch with high and low temperature resistance, wear resistance, and tear resistance, calculated by mass parts, includes the following steps:

[0038] S1. Charge 100 mass parts of fluorosilicone rubber raw rubber (vinyl content is 0.05%, number average molecular weight is 600,000) into a Banbury mixer. The initial temperature of the Banbury mixer is 80°C, and it is plasticized for 4 minutes. Then, sequentially add 2 mass parts of vinyl carboxyl liquid silicone rubber, 30 mass parts of fluorosilane-modified silica, 2 mass parts of zinc polymethacrylate, 2 mass parts of nano-cerium oxide, 2 mass parts of N,N'-di(β-naphthyl)-p-phenylenediamine, 1 mass part of dibenzyl hydroquinone ether, 10 parts of polytetrafluoroethylene micropowder, and 10 mass parts of molybdenum disulfide. Carry out pressure Banbury mixing, control the temperature at 85 - 90°C, and after mixing for 10 minutes, take out the mixed rubber and cool it to room temperature to obtain a fluorosilicone rubber premix.

[0039] S2. Add 3 mass parts of dibenzoyl peroxide and 1 mass part of benzyltriphenylphosphonium chloride to the fluorosilicone rubber premix described in S1. At room temperature, carry out triangular bale mixing on an XK160 two-roll mill for 8 minutes. The roll gap of the mill is 1.5 mm. After mixing, quickly blow it with cold air to cool the mixed rubber to room temperature, and store it in an environment with a temperature below 28°C and an air humidity < 70%.

[0040] S3. Use a flat vulcanizer to vulcanize for 8 minutes at a temperature of 170°C and a pressure of 15MPa, and then perform a second-stage vulcanization in a blast oven at 200°C for 3 hours to obtain a high- and low-temperature resistant, wear-resistant, and tear-resistant fluorosilicone rubber compound.

[0041] Example 2

[0042] A method for preparing a high-low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber compound, calculated by mass, comprises the following steps:

[0043] S1. Put 100 parts by mass of fluorosilicone rubber raw rubber (vinyl content of 0.15%, number average molecular weight of 400,000) into an internal mixer with a starting temperature of 85°C and plasticization for 3 minutes, then add 2 parts by mass of vinylphenol hydroxyl liquid silicone rubber, 20 parts by mass of high wear-resistant carbon black, 10 parts by mass of potassium titanate whiskers, 2 parts by mass of bis-[γ-(triethoxysilyl)propyl]tetrasulfide, 2 parts by mass of vinylfluorosilane modified carbon nanotubes, 2 parts by mass of N-isopropyl-N'-phenyl-p-phenylenediamine, 1 part by mass of 2-mercaptobenzimidazole zinc salt, 15 parts by mass of graphite, and 5 parts by mass of layered nano zirconium phosphate, pressurize and internally mix, control the temperature at 90-95°C, take out the mixed rubber after mixing for 12 minutes and cool it to room temperature to obtain a fluorosilicone rubber premix.

[0044] S2. Add 2 parts by mass of diisopropylbenzene peroxide and 2 parts by mass of triallyl triisocyanurate to the fluorosilicone rubber premix described in S1, and mix them in triangle packages on an XK160 double-roll open mill for 8 minutes at room temperature. The roller spacing of the open mill is 2 mm. After mixing, blow cold air quickly to cool the mixed rubber to room temperature, and store it in an environment below 28°C and with an air humidity of <70.

[0045] S3. Use a flat vulcanizer to vulcanize for 6 minutes at a temperature of 175°C and a pressure of 13MPa, and then perform a second-stage vulcanization in a blast oven at 200°C for 2 hours to obtain a high- and low-temperature resistant, wear-resistant, and tear-resistant fluorosilicone rubber compound.

[0046] Example 3

[0047] A method for preparing a high-low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber compound, calculated by mass, comprises the following steps:

[0048] S1. Put 100 parts by mass of fluorosilicone rubber raw rubber (vinyl content is 0.5%, number average molecular weight is 300,000) into a Banbury mixer. The initial mixing temperature is 80 °C, and plasticize for 2 min. Then add 5 parts by mass of vinyl urethane-based liquid silicone rubber, 20 parts by mass of silica powder, 5 parts by mass of potassium titanate whiskers, 2 parts by mass of zinc polymethacrylate, 3 parts by mass of glass microspheres, 2 parts by mass of lanthanum oxide nanoparticles, 3 parts by mass of zinc 2-mercaptobenzimidazole, 10 parts by mass of molybdenum disulfide, and 3 parts by mass of layered nanozirconium phosphate in sequence. Carry out pressure mixing, control the temperature at 95 - 100 °C, and after mixing for 13 min, take out the mixed rubber and cool it to room temperature to obtain the fluorosilicone rubber premix.

[0049] S2. Add 4 parts by mass of 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane and 2 parts by mass of bisphenol-AF to the fluorosilicone rubber premix described in S1. At room temperature, mix by making triangular bales on an XK160 two-roll mill for 6 min. The roll spacing of the mill is 1 mm. After mixing, quickly blow with cold air to cool the mixed rubber to room temperature, and store it in an environment below 28 °C and with air humidity < 70%.

[0050] S3. Use a flat vulcanizer to vulcanize for 10 min under the conditions of a temperature of 165 °C and a pressure of 10 MPa, and then carry out secondary vulcanization in a forced-air oven at 200 °C for 3 h to obtain a fluorosilicone rubber mixed rubber with high and low temperature resistance, wear resistance, and tear resistance.

[0051] Example 4

[0052] A preparation method of a fluorosilicone rubber mixed rubber with high and low temperature resistance, wear resistance, and tear resistance, calculated by mass parts, includes the following steps:

[0053] S1. Put 100 parts by mass of fluorosilicone rubber raw rubber (vinyl content is 0.25%, number average molecular weight is 400,000) into a Banbury mixer. The initial mixing temperature is 85 °C, and plasticize for 2.5 min. Then add 5 parts by mass of vinyl carboxyl-based liquid fluorosilicone rubber, 20 parts by mass of fluorosilane-modified silica, 5 parts by mass of silica powder, 5 parts by mass of potassium titanate whiskers, 2 parts by mass of bis-[γ-(triethoxysilyl)propyl] tetrasulfide, 2 parts by mass of glass microspheres, 2 parts by mass of vinyl fluorosilane-modified carbon nanotubes, 4 parts by mass of N-isopropyl-N'-phenyl-p-phenylenediamine, 10 parts by mass of graphite, 5 parts by mass of layered nanozirconium phosphate, and 5 parts by mass of polytetrafluoroethylene micropowder in sequence. Carry out pressure mixing, control the temperature at 90 - 95 °C, and after mixing for 12 min, take out the mixed rubber and cool it to room temperature to obtain the fluorosilicone rubber premix.

[0054] S2. Add 4 parts by mass of tert-butyl perbenzoate, 2 parts by mass of bisphenol-AF and 1 part by mass of magnesium oxide to the fluorosilicone rubber premix described in S1, and mix them in triangle packages on an XK160 double-roll open mill for 8 minutes at room temperature. The roller spacing of the open mill is 1.5 mm. After mixing, blow cold air quickly to cool the mixed rubber to room temperature, and store it in an environment below 28°C and with an air humidity of <70.

[0055] S3. Use a flat vulcanizer to vulcanize for 8 minutes at a temperature of 170°C and a pressure of 15MPa, and then perform a second-stage vulcanization in a blast oven at 200°C for 2 hours to obtain a high- and low-temperature resistant, wear-resistant, and tear-resistant fluorosilicone rubber compound.

[0056] Example 5

[0057] A method for preparing a high-low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber compound, calculated by mass, comprises the following steps:

[0058] S1. Put 100 parts by mass of fluorosilicone rubber raw rubber (vinyl content of 0.15%, number average molecular weight of 500,000) into an internal mixer, the starting temperature of internal mixing is 85°C, and the mixing is plasticized for 3 minutes. Then, 5 parts by mass of vinyl urethane-based liquid silicone rubber, 20 parts by mass of fluorosilane-modified white carbon black, 10 parts by mass of silicon powder, 3 parts by mass of zinc polymethacrylate, 2 parts by mass of glass microbeads, 2 parts by mass of nano-cerium oxide, 1 part by mass of vinyl fluorosilane-modified carbon nanotubes, 2 parts by mass of hydroquinone dibenzyl ether, 2 parts by mass of 2-mercaptobenzimidazole zinc salt, 10 parts by mass of molybdenum disulfide, 2 parts by mass of layered nano zirconium phosphate, and 3 parts by mass of polytetrafluoroethylene powder are added in sequence, and the mixture is pressurized and internally mixed at a temperature of 80-85°C. After mixing for 10 minutes, the mixed rubber is taken out and cooled to room temperature to obtain a fluorosilicone rubber premix.

[0059] S2. Add 4 parts by mass of dibenzoyl peroxide, 2 parts by mass of benzyltriphenylphosphine chloride and 1 part by mass of magnesium oxide to the fluorosilicone rubber premix described in S1, and mix them in triangle packages on an XK160 double-roll open mill for 7 minutes at room temperature. The roller spacing of the open mill is 1 mm. After mixing, blow cold air quickly to cool the mixed rubber to room temperature, and store it in an environment below 28°C and with an air humidity of <70.

[0060] S3. Use a flat vulcanizer to vulcanize for 6 minutes at a temperature of 175°C and a pressure of 20MPa, and then perform a second-stage vulcanization in a 200°C blast oven for 2 hours to obtain a high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber compound.

[0061] Example 6

[0062] A method for preparing a high-low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber compound, calculated by mass, comprises the following steps:

[0063] S1. Charge 100 parts by mass of fluorosilicone rubber raw rubber (vinyl content is 0.35%, number-average molecular weight is 450,000) into a Banbury mixer. The initial temperature of the Banbury mixing is 90°C, and plasticize for 3 min. Then, sequentially add 2 parts by mass of vinyl urethane-based liquid silicone rubber, 3 parts by mass of vinyl carboxyl-based liquid fluorosilicone rubber, 30 parts by mass of fluorosilane-modified silica, 10 parts by mass of silica powder, 3 parts by mass of zinc polymethacrylate, 2 parts by mass of bis-[γ-(triethoxysilyl)propyl] tetrasulfide, 1.5 parts by mass of lanthanum oxide nanoparticles, 1.5 parts by mass of vinyl fluorosilane-modified carbon nanotubes, 2 parts by mass of N,N'-bis(β-naphthyl)-p-phenylenediamine, 2 parts by mass of zinc 2-mercaptobenzimidazole, 10 parts by mass of molybdenum disulfide, 5 parts by mass of graphite, and 5 parts by mass of layered nanozirconium phosphate. Carry out pressure Banbury mixing, control the temperature at 80 - 85°C, and after mixing for 10 min, take out the mixed rubber and cool it to room temperature to obtain a fluorosilicone rubber premix.

[0064] S2. Add 4 parts by mass of benzoyl peroxide, 2 parts by mass of benzyltriphenylphosphonium chloride, and 1 part by mass of magnesium oxide to the fluorosilicone rubber premix described in S1. At room temperature, carry out triangular bale mixing on an XK160 two-roll mill for 7 min. The roll gap of the mill is 1 mm. After the mixing is completed, quickly blow with cold air to cool the mixed rubber to room temperature, and store it in an environment with a temperature below 28°C and an air humidity < 70%.

[0065] S3. Use a flat vulcanizer to vulcanize for 6 min under the conditions of a temperature of 175°C and a pressure of 20 MPa, and then carry out secondary vulcanization in a forced-air oven at 200°C for 2 h to obtain a fluorosilicone rubber mixed rubber with high and low temperature resistance, wear resistance, and tear resistance.

[0066] Comparative Example 1

[0067] Do not add anti-friction fillers, and the remaining formulation and operations refer to Example 1.

[0068] Comparative Example 2

[0069] Do not add reactive liquid rubber compatibilizer, and the remaining formulation and operations refer to Example 2.

[0070] Comparative Example 3

[0071] Do not add tear resistance aids, and the remaining formulation and operations refer to Example 3.

[0072] Comparative Example 4

[0073] Do not add high temperature resistant aids, and the remaining formulation and operations refer to Example 4.

[0074] Comparative Example 5

[0075] Do not add tear resistance aids and high temperature resistant aids, and the remaining formulation and operations refer to Example 5.

[0076] Comparative Example 6

[0077] Replace the added molybdenum disulfide, graphite, and layered nanozirconium phosphate treated with oxygen plasma with molybdenum disulfide, graphite, and layered nanozirconium phosphate without oxygen plasma treatment, and the remaining formulation and operations refer to Example 6.

[0078] Performance Test

[0079] Perform performance tests on the examples and comparative examples according to the following standards, and the results are shown in Table 1:

[0080] 1. Tensile strength and elongation at break of the sample before the high-temperature resistance test: Refer to "GB / T528-2009 Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber, tensile rate is 500mm / min" for testing.

[0081] 2. Hardness / Shore A of the sample before the high-temperature resistance test: Refer to "GB / T531.1-2008 Experimental method for indentation hardness of vulcanized rubber or thermoplastic rubber - Part 1: Shore hardness tester method (Shore hardness)" for testing.

[0082] 3. Changes in tensile strength, elongation at break, and hardness after the high-temperature resistance test (250°C × 70h): Refer to "GB / T3512-2014 Accelerated thermal aging and heat resistance test for vulcanized rubber or thermoplastic rubber" for testing.

[0083] 4. Compression set (250°C × 70h): Refer to "GB / T7759.1-2015 Determination of compression set of vulcanized rubber or thermoplastic rubber - Part 1: At normal and high temperatures" for testing.

[0084] 5. Oil resistance test (200°C × 70h): Refer to "GB / T1690-2010 Test method for resistance of vulcanized rubber or thermoplastic rubber to liquids" for testing.

[0085] 6. Low-temperature brittleness temperature (-50°C): Refer to "GB / T15256-2014 Determination of low-temperature brittleness of vulcanized rubber or thermoplastic rubber" for testing.

[0086] 7. Tear strength test: Refer to "GB / T529-2008 Determination of tear strength of vulcanized rubber or heat-vulcanized rubber (Method C)" for testing.

[0087] 8. Akron abrasion test: Refer to "GB / T1689-2014 Determination of abrasion resistance of vulcanized rubber (using Akron abrasion tester)" for testing.

[0088] Table 1 Performance test results of fluorosilicone rubber masterbatches of examples and comparative examples

[0089]

[0090] As can be seen from the test results in Table 1, before the high-temperature resistance experiment (250 °C × 70 h), the high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber masterbatches prepared in Examples 1 to 6 all showed excellent tensile strength and tear resistance, indicating that fluorosilane-modified silica, high-abrasion furnace black, silica powder, and potassium titanate whiskers have good reinforcing effects. Moreover, the reactive liquid rubber compatibilizer and tear-resistant additives improve the service performance of fluorosilicone rubber in low-temperature environments through plasticization and compatibilization effects, and synergistically enhance the high and low temperature stability, oil resistance, wear resistance, and tear strength of fluorosilicone rubber by regulating the multiple crosslinked network structure of fluorosilicone rubber and strengthening the interface interaction between rubber and fillers.

[0091] Compared with Comparative Example 1 and Comparative Example 6, the high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber masterbatches prepared in Examples 1 to 6 showed better wear resistance, indicating that anti-friction fillers such as molybdenum disulfide, graphite, layered nanozirconium phosphate, and polytetrafluoroethylene fine powder after oxygen plasma treatment not only reduced the friction coefficient of the fluorosilicone rubber masterbatch, but also had good nano-enhancement effects on the rubber matrix. At the same time, treating the surface of the fillers by oxygen plasma technology helps to strengthen the interface interaction between nano-fillers such as molybdenum disulfide, graphite, and layered nanozirconium phosphate and fluorosilicone rubber, and improve their dispersibility and compatibility.

[0092] Compared with Comparative Example 2, the high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber masterbatches prepared in Examples 1 to 6 had excellent low-temperature performance. By adding a reactive liquid rubber compatibilizer to increase the lubrication between rubber molecular chains, it not only improved the interface interaction between the rubber matrix and the fillers, but also avoided the hardening of the fluorosilicone rubber masterbatch at low temperatures, effectively improving the service performance of the fluorosilicone rubber masterbatch in low-temperature environments, and making the low-temperature brittle temperature of the fluorosilicone rubber masterbatch lower than -50 °C.

[0093] Compared with Comparative Example 3, the high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber masterbatches prepared in Examples 1 to 6 had excellent tear resistance, indicating that tear-resistant additives such as zinc polymethacrylate, bis-[γ-(triethoxysilyl)propyl]tetrasulfide, and glass microspheres can inhibit the development of silver streaks and cracks in the rubber matrix, and synergistically enhance the tear strength of the fluorosilicone rubber masterbatch.

[0094] Compared with Comparative Example 4 and Comparative Example 5, the high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber masterbatches prepared in Examples 1 to 6 had excellent high-temperature performance, indicating that high-temperature resistant additives such as nano-cerium oxide, nano-lanthanum oxide, and fluorosilane-modified carbon nanotubes can not only improve the antioxidant performance and mechanical stability of fluorosilicone rubber at high temperatures, but also have good nano-enhancement effects on the rubber matrix, further improving its high-temperature performance.

[0095] The high and low temperature resistant, wear resistant and tear resistant fluorosilicone rubber masterbatches prepared in Examples 1 to 6 have outstanding properties such as high and low temperature resistance, oil resistance, low compression set and tear resistance, and can be applied to the seals of high-end hydraulic equipment and new energy vehicle power systems under harsh working conditions.

[0096] The high and low temperature resistant, wear resistant and tear resistant fluorosilicone rubber masterbatches prepared in Examples 1 to 6 have outstanding wear resistance, with an Akron abrasion ≤ 0.18 cm 3 / 1.61 km, which is only about one-third of the fluorosilicone rubber masterbatches prepared in Comparative Examples 1 to 6. This is because the selected anti-friction fillers and reactive liquid rubber compatibilizers play a good plasticizing and interface strengthening role, reducing the friction coefficient of the fluorosilicone rubber masterbatch and improving the anti-wear performance.

[0097] As mentioned above, it is only the preferred embodiments of the present invention, and there is no any form of restriction on the present invention. Although the present invention has been disclosed as above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments by using the disclosed technical content within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any brief modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber compound, characterized by: The invention comprises the following raw materials in parts by weight: Fluorosilicone rubber raw rubber: 100 parts; Reactive liquid rubber compatibilizer: 2-5 parts; Reinforcing filler: 20-40 parts; Anti-tear additive: 2-5 parts; High temperature resistant additive: 1 to 3 parts; Vulcanizing agent: 2-4 parts; Accelerator: 1-3 parts; Anti-aging agent: 2-4 parts; Friction-reducing filler: 10-20 parts; The vinyl content of the fluorosilicone rubber raw rubber is 0.05% to 0.5%, and the number average molecular weight is 200,000 to 600,000.

2. The high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber compound according to claim 1, characterized in that: The reactive liquid rubber compatibilizer is at least one of vinyl carboxyl liquid silicone rubber, vinyl phenol hydroxyl liquid silicone rubber, vinyl urethane liquid silicone rubber, and vinyl carboxyl liquid fluorosilicone rubber.

3. The high and low temperature resistant, wear resistant and tear resistant fluorosilicone rubber compound according to claim 1, characterized in that: The reinforcing filler is at least one of fluorosilane-modified white carbon black, high wear-resistant carbon black, silicon micropowder, and potassium titanate whisker.

4. The high and low temperature resistant, wear resistant and tear resistant fluorosilicone rubber compound according to claim 1, characterized in that: The anti-tearing aid is at least one of polymethacrylate zinc, bis-[γ-(triethoxysilyl)propyl]tetrasulfide and glass microspheres.

5. The high and low temperature resistant, wear resistant and tear resistant fluorosilicone rubber compound according to claim 1, characterized in that: The high temperature resistant auxiliary agent is at least one of nano cerium oxide, nano lanthanum oxide and vinyl fluorosilane modified carbon nanotubes.

6. The high and low temperature resistant, wear resistant and tear resistant fluorosilicone rubber compound according to claim 1, characterized in that: The vulcanizing agent is at least one of dibenzoyl peroxide, dicumyl peroxide, tert-butyl perbenzoate, and 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane.

7. The high and low temperature resistant, wear resistant and tear resistant fluorosilicone rubber compound according to claim 1, characterized in that: The accelerator is at least one of benzyltriphenylphosphine chloride, triallyl triisocyanurate, bisphenol-AF, and magnesium oxide.

8. The high and low temperature resistant, wear resistant and tear resistant fluorosilicone rubber compound according to claim 1, characterized in that: The antioxidant is at least one of N,N'-di(β-naphthyl)-p-phenylenediamine, hydroquinone dibenzyl ether, N-isopropyl-N'-phenyl-p-phenylenediamine and 2-mercaptobenzimidazole zinc salt.

9. The high and low temperature resistant, wear resistant and tear resistant fluorosilicone rubber compound according to claim 1, characterized in that: The friction-reducing filler is at least one of molybdenum disulfide, graphite, layered nano zirconium phosphate, and polytetrafluoroethylene powder treated with oxygen plasma.

10. A method for preparing the high and low temperature resistant, wear resistant and tear resistant fluorosilicone rubber compound according to any one of claims 1 to 9, characterized in that: The preparation of the rubber compound comprises the following steps: S1. Add fluorosilicone rubber raw rubber, reactive liquid rubber extender, reinforcing filler, tear-resistant additive, high temperature resistant additive, antioxidant and anti-friction filler into an internal mixer in proportion, control the temperature at 80-100°C, mix for 10-15 minutes, take out and cool to room temperature to obtain fluorosilicone rubber premix; S2. Add the vulcanizer and accelerator to the fluorosilicone rubber premix described in S1, mix them in triangle packages on a double-roll open mill at room temperature for 6 to 8 minutes, with the roller spacing of the open mill being 0.5 to 2 mm. After mixing, blow cold air quickly to cool the mixed rubber to room temperature, and store it in an environment below 28°C and with an air humidity of less than 70%. S3. The mixed gel in S2 is vulcanized for 6 to 10 minutes using a flat vulcanizer at a temperature of 160 to 175°C and a pressure of 10 to 20 MPa, and then subjected to a second-stage vulcanization in a 200°C blast oven for 2 to 3 hours to obtain a high and low temperature resistant, wear-resistant and tear-resistant fluorosilicone rubber compound.

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