Oil-resistant rubber composite material for isolating valve of fuel tank

Abstract

The invention relates to the technical field of rubber materials, in particular to an oil-resistant rubber composite material for an isolating valve of a fuel tank. In order to improve the tolerance of the composite rubber material to fuel oil substances, the fluorosilicone rubber is used as a rubber raw material, the carbon black is modified, and a long carbon chain and a silicon-oxygen bond are introduced into the carbon black, so that the compatibility of the carbon black and the fluorosilicone rubber is improved, and the elasticity of the rubber composite material is improved; and fluorine and silicon elements are introduced to the surface of the carbon black, so that the polarity of the rubber composite material is further enhanced, the tolerance to fuel oil is improved, and the service life of the rubber composite material is effectively prolonged.

Description

Technical Field

[0001] This invention relates to the field of rubber materials technology, specifically to an oil-resistant rubber composite material for a fuel tank isolation valve. Background Technology

[0002] A fuel tank isolation valve is a key component used to control fuel flow. Its main function is to open or close the fuel supply when needed. Therefore, during use, the isolation valve is in direct contact with fuel. However, rubber materials are often used in isolation valves to provide a sealing and isolation function. In the fuel environment, the rubber material in the isolation valve is directly exposed to the erosion and swelling of various organic components in the fuel, causing a decrease in the strength and performance of the rubber material and affecting the use of the isolation valve. Therefore, the rubber material used in fuel tank isolation valves must be able to withstand contact with fuel to ensure the reliability of the valve, thereby improving the stability coefficient during use and enhancing the durability of the product. Summary of the Invention

[0003] The purpose of this invention is to provide an oil-resistant rubber composite material for a fuel tank isolation valve to solve the problems mentioned in the background art.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve, comprising the following steps:

[0005] S1. Preparation of modified carbon black;

[0006] S11. Disperse 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane in tetrahydrofuran, stir and mix for 0.5-1 h, then under nitrogen atmosphere protection, add aluminum chloride, and continue stirring and mixing for 15-30 min to obtain a dispersion of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane;

[0007] Under a nitrogen atmosphere, 2,5-diaminotrifluorotoluene was dispersed in DMAc and ultrasonically mixed for 1-2 hours. Then, 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane dispersion was added dropwise at room temperature with continuous stirring. After the addition was completed, the solution was heated to 70-75°C and stirred for 2-4 hours. Excess solvent was removed by rotary evaporation. The product was washed 1-3 times with deionized water, and the remaining product was vacuum evaporated to constant weight to obtain a fluorosilicone modified intermediate.

[0008] S12. Disperse carbon black in concentrated nitric acid, heat to 55-65℃, and ultrasonically disperse for 2-6 hours. After centrifugation to separate the precipitate, wash the precipitate with deionized water until neutral. Disperse the carbon black in DMF, ultrasonically disperse for 0.5-1 hours, add benzoyl chloride, heat to 60-70℃, stir for 2-5 hours, centrifuge to separate the precipitate, wash the precipitate 3-5 times with deionized water, dry to constant weight at 70-80℃, disperse it in DMAc, add triethylamine, stir for 1-1.5 hours, add fluorosilicone modified intermediate, heat to 85-90℃, stir for 2-4 hours, centrifuge to separate the precipitate, and dry to constant weight to obtain fluorosilicone modified carbon black.

[0009] S13. Disperse fluorosilicone modified carbon black in DMF, ultrasonically disperse for 0.5-1 h, add tetra(triphenylphosphine)palladium, continue mixing for 5-10 min, then introduce butadiene, heat to 75-85℃, maintain butadiene reaction pressure at 0.5-1.5 MPa, react for 1-6 h, then stop heating, centrifuge to separate the precipitate, wash with deionized water, and vacuum dry for 12-24 h to obtain modified carbon black;

[0010] S2. Preparation of oil-resistant rubber composite materials;

[0011] S21. After the fluorosilicone rubber is milled and passed through the mill 3-5 times, activator and antioxidant are added, the temperature is raised to 55-120℃ and mixed for 10-25 minutes, plasticizer and modified carbon black are added, and the mixture is continued to be mixed for 5-20 minutes. Then, vulcanizing agent is added, and the mixture is passed through the mill 3-5 times to obtain the compound.

[0012] S22. After the rubber compound is left to stand at room temperature for 12-24 hours, it is heated and vulcanized to obtain an oil-resistant rubber composite material for fuel tank isolation valve.

[0013] Furthermore, in step S11, the mass ratio of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane, aluminum chloride, and 2,5-diaminotrifluorotoluene is 10:(0.03-0.05):(0.85-0.98) by weight.

[0014] Furthermore, in step S12, the concentration of the concentrated nitric acid is 68-90 wt%.

[0015] Furthermore, in step S12, the mass ratio of carbon black, benzoyl chloride, and triethylamine is 10:(2-4):

[0016] (0.1-0.3).

[0017] Furthermore, in step S12, the mass ratio of the carbon black to the fluorosilicone modified intermediate is 10:(0.5-4).

[0018] Furthermore, in step S13, the mass ratio of the fluorosilicone modified carbon black to tetra(triphenylphosphine)palladium is 10:

[0019] (0.03-0.08).

[0020] Furthermore, in step S13, the mass ratio of the fluorosilicone modified carbon black to tetra(triphenylphosphine)palladium is 10:

[0021] (0.03-0.08).

[0022] Furthermore, by weight, in step S21, the compound consists of the following components: 100 parts fluorosilicone rubber, 40-55 parts modified carbon black, 1-8 parts activator, 0.5-3 parts antioxidant, 1-3 parts plasticizer, and 1-2.5 parts vulcanizing agent.

[0023] Wherein, the activator is active zinc oxide; the antioxidant is any one of antioxidant 4010 and antioxidant RD; the plasticizer is a phthalate plasticizer; and the vulcanizing agent is dicumyl peroxide, benzoyl peroxide, or di-tert-butyl peroxide.

[0024] Furthermore, in step S22, the vulcanization temperature is 165-175℃, the vulcanization pressure is 10-15MPa, and the vulcanization time is 10-15min.

[0025] Furthermore, an oil-resistant rubber composite material for a fuel tank isolation valve is prepared by the above method.

[0026] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0027] 1. In order to improve the resistance of composite rubber materials to fuel substances, this invention uses fluorosilicone rubber as a rubber raw material. Fluorosilicone rubber contains fluorine and silicon elements, has high polarity, and has excellent resistance to swelling of non-polar and weakly polar oils in fuel. Furthermore, due to its excellent heat resistance, fluorosilicone rubber can effectively resist the high temperature environment in the fuel tank, thereby extending the service life of the fuel tank isolation valve.

[0028] 2. However, the addition of conventional reinforcing materials such as carbon black to fluorosilicone rubber can result in poor softness and elasticity. Therefore, this invention also modifies the carbon black. First, the carbon black is oxidized with concentrated nitric acid, and then its surface is carboxylated with benzoyl chloride to generate active carboxyl groups on the carbon black surface. Then, this invention uses 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane as a raw material and reacts it with 2,5-diaminotrifluorotoluene containing fluorine to generate a fluorosilicone modified intermediate with long carbon chains and silicon-oxygen bonds. This intermediate contains a large amount of fluorine and silicon, both of which are highly polar and can further improve the composite material's resistance to fuel swelling. Furthermore, its long carbon chains and silicon-oxygen bonds have molecular flexibility. Grafting them onto the carbon black surface can effectively improve the bonding performance between carbon black and fluorosilicone rubber and avoid the decrease in elasticity of fluorosilicone rubber after the addition of carbon black.

[0029] After reacting the fluorosilicone modified intermediate with carbon black, the present invention further places the fluorosilicone carbon black in a butadiene environment, and under the action of a catalyst, the conjugated diene in the butadiene reacts with the amino group on the surface of the carbon black, thereby grafting the butadiene structure on the surface of the carbon black, thereby effectively improving the compatibility between carbon black and fluorosilicone rubber.

[0030] Furthermore, the vulcanizing agent used in this invention is a peroxide-based crosslinking agent. The butadiene structure on the surface of carbon black can further participate in the rubber vulcanization and crosslinking process under the action of this type of peroxide crosslinking agent, which can effectively improve the comprehensive performance of rubber composite materials. Detailed Implementation

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] The fluorosilicone rubber used in this application is LS4-9060 type fluorosilicone rubber; the activator used is active zinc oxide with a purity >98% and a density of 5.606 g / cm³. 3 The antioxidant used is antioxidant 4010; the plasticizer used is dioctyl phthalate; the vulcanizing agent used is benzoyl peroxide; and the carbon black used is N990 type carbon black.

[0033] Example 1. A method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve, comprising the following steps:

[0034] S1. Preparation of modified carbon black;

[0035] S11. By weight, 10 parts of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane were dispersed in tetrahydrofuran. After stirring and mixing for 0.5 h, under nitrogen atmosphere protection, 0.03 parts of aluminum chloride were added, and stirring and mixing were continued for 15 min to obtain a dispersion of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane.

[0036] Under a nitrogen atmosphere, 0.85 parts of 2,5-diaminotrifluorotoluene were dispersed in DMAc and ultrasonically mixed for 1 h. Then, 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane dispersion was added dropwise at room temperature for 2 h with continuous stirring. After the addition was completed, the solution was heated to 70 °C and stirred for 2 h. The excess solvent was removed by rotary evaporation. The product was washed once with deionized water and the remaining product was vacuum evaporated to constant weight to obtain the fluorosilicone modified intermediate.

[0037] S12. By weight, 10 parts of carbon black were dispersed in 68wt% concentrated nitric acid, heated to 55℃, and ultrasonically dispersed for 4 hours. After centrifugation to separate the precipitate, the precipitate was washed with deionized water until neutral. The carbon black was then dispersed in DMF and ultrasonically dispersed for 0.5 hours. 2 parts of benzoyl chloride were added, the temperature was raised to 60℃, and the reaction was stirred for 2 hours. The precipitate was then centrifuged, washed three times with deionized water, and dried at 75℃ to constant weight. The precipitate was then dispersed in DMAc, 0.1 parts of triethylamine were added, and the reaction was stirred for 1 hour. 0.5 parts of fluorosilicone modified intermediate were added, the temperature was raised to 85℃, and the reaction was stirred for 2 hours. The precipitate was then centrifuged and dried to constant weight to obtain fluorosilicone modified carbon black.

[0038] S13. By weight, 10 parts of fluorosilicone modified carbon black were dispersed in DMF and ultrasonically dispersed for 0.5 h. Then, 0.05 parts of tetra(triphenylphosphine)palladium were added and mixed for another 5 min. Butadiene was then introduced and the temperature was raised to 75 °C. The reaction pressure of butadiene was maintained at 0.5 MPa. After reacting for 4 h, the heating was stopped, the precipitate was separated by centrifugation, washed with deionized water, and vacuum dried for 12 h to obtain modified carbon black.

[0039] S2. Preparation of oil-resistant rubber composite materials;

[0040] S21. By weight, after 100 parts of fluorosilicone rubber are milled and passed through the mill three times, 2 parts of activator and 1.5 parts of antioxidant are added, the mixture is heated to 75°C and mixed for 20 minutes, then 1.5 parts of plasticizer and 40 parts of modified carbon black are added, the mixture is continued to be mixed for 15 minutes, then 1.5 parts of vulcanizing agent are added, and the mixture is passed through the mill three times to obtain the compound.

[0041] S22. After the compounded rubber is left to stand at room temperature for 16 hours, it is heated to 170℃ for vulcanization. The vulcanization pressure is 10MPa and the vulcanization time is 10min. After vulcanization, an oil-resistant rubber composite material for fuel tank isolation valve is obtained.

[0042] Example 2. A method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve, comprising the following steps:

[0043] Compared with Example 1, this example increases the amount of 2,5-diaminotrifluorotoluene added in step S11, while the other steps remain unchanged;

[0044] S1. Preparation of modified carbon black;

[0045] S11. By weight, 10 parts of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane were dispersed in tetrahydrofuran. After stirring and mixing for 0.5 h, under nitrogen atmosphere protection, 0.03 parts of aluminum chloride were added, and stirring and mixing were continued for 15 min to obtain a dispersion of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane.

[0046] Under a nitrogen atmosphere, 0.98 parts of 2,5-diaminotrifluorotoluene were dispersed in DMAc and ultrasonically mixed for 1 h. Then, 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane dispersion was added dropwise at room temperature for 2 h with continuous stirring. After the addition was completed, the solution was heated to 70 °C and stirred for 2 h. The excess solvent was removed by rotary evaporation. The product was washed once with deionized water and the remaining product was vacuum evaporated to constant weight to obtain the fluorosilicone modified intermediate.

[0047] S12. By weight, 10 parts of carbon black were dispersed in 68wt% concentrated nitric acid, heated to 55℃, and ultrasonically dispersed for 4 hours. After centrifugation to separate the precipitate, the precipitate was washed with deionized water until neutral. The carbon black was then dispersed in DMF and ultrasonically dispersed for 0.5 hours. 2 parts of benzoyl chloride were added, the temperature was raised to 60℃, and the reaction was stirred for 2 hours. The precipitate was then centrifuged, washed three times with deionized water, and dried at 75℃ to constant weight. The precipitate was then dispersed in DMAc, 0.1 parts of triethylamine were added, and the reaction was stirred for 1 hour. 0.5 parts of fluorosilicone modified intermediate were added, the temperature was raised to 85℃, and the reaction was stirred for 2 hours. The precipitate was then centrifuged and dried to constant weight to obtain fluorosilicone modified carbon black.

[0048] S13. By weight, 10 parts of fluorosilicone modified carbon black were dispersed in DMF and ultrasonically dispersed for 0.5 h. Then, 0.05 parts of tetra(triphenylphosphine)palladium were added and mixed for another 5 min. Butadiene was then introduced and the temperature was raised to 75 °C. The reaction pressure of butadiene was maintained at 0.5 MPa. After reacting for 4 h, the heating was stopped, the precipitate was separated by centrifugation, washed with deionized water, and vacuum dried for 12 h to obtain modified carbon black.

[0049] Example 3. A method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve, comprising the following steps:

[0050] Compared with Example 1, this example increases the amount of benzoyl chloride added in step S12, while the other steps remain unchanged;

[0051] S1. Preparation of modified carbon black;

[0052] S11. By weight, 10 parts of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane were dispersed in tetrahydrofuran. After stirring and mixing for 0.5 h, under nitrogen atmosphere protection, 0.03 parts of aluminum chloride were added, and stirring and mixing were continued for 15 min to obtain a dispersion of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane.

[0053] Under a nitrogen atmosphere, 0.85 parts of 2,5-diaminotrifluorotoluene were dispersed in DMAc and ultrasonically mixed for 1 h. Then, 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane dispersion was added dropwise at room temperature for 2 h with continuous stirring. After the addition was completed, the solution was heated to 70 °C and stirred for 2 h. The excess solvent was removed by rotary evaporation. The product was washed once with deionized water and the remaining product was vacuum evaporated to constant weight to obtain the fluorosilicone modified intermediate.

[0054] S12. By weight, 10 parts of carbon black were dispersed in 68wt% concentrated nitric acid, heated to 55℃, and ultrasonically dispersed for 4 hours. After centrifugation to separate the precipitate, the precipitate was washed with deionized water until neutral. The carbon black was then dispersed in DMF and ultrasonically dispersed for 0.5 hours. 4 parts of benzoyl chloride were added, the temperature was raised to 60℃, and the reaction was stirred for 2 hours. The precipitate was then centrifuged, washed three times with deionized water, and dried at 75℃ to constant weight. The precipitate was then dispersed in DMAc, 0.1 parts of triethylamine were added, and the reaction was stirred for 1 hour. 0.5 parts of fluorosilicone modified intermediate were added, the temperature was raised to 85℃, and the reaction was stirred for 2 hours. The precipitate was then centrifuged and dried to constant weight to obtain fluorosilicone modified carbon black.

[0055] S13. By weight, 10 parts of fluorosilicone modified carbon black were dispersed in DMF and ultrasonically dispersed for 0.5 h. Then, 0.05 parts of tetra(triphenylphosphine)palladium were added and mixed for another 5 min. Butadiene was then introduced and the temperature was raised to 75 °C. The reaction pressure of butadiene was maintained at 0.5 MPa. After reacting for 4 h, the heating was stopped, the precipitate was separated by centrifugation, washed with deionized water, and vacuum dried for 12 h to obtain modified carbon black.

[0056] Example 4. A method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve, comprising the following steps:

[0057] Compared with Example 1, this example increases the amount of fluorosilicone modified intermediate added in step S12, while the other steps remain unchanged;

[0058] S1. Preparation of modified carbon black;

[0059] S11. By weight, 10 parts of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane were dispersed in tetrahydrofuran. After stirring and mixing for 0.5 h, under nitrogen atmosphere protection, 0.03 parts of aluminum chloride were added, and stirring and mixing were continued for 15 min to obtain a dispersion of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane.

[0060] Under a nitrogen atmosphere, 0.85 parts of 2,5-diaminotrifluorotoluene were dispersed in DMAc and ultrasonically mixed for 1 h. Then, 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane dispersion was added dropwise at room temperature for 2 h with continuous stirring. After the addition was completed, the solution was heated to 70 °C and stirred for 2 h. The excess solvent was removed by rotary evaporation. The product was washed once with deionized water and the remaining product was vacuum evaporated to constant weight to obtain the fluorosilicone modified intermediate.

[0061] S12. By weight, 10 parts of carbon black were dispersed in 68wt% concentrated nitric acid, heated to 55℃, and ultrasonically dispersed for 4 hours. After centrifugation to separate the precipitate, the precipitate was washed with deionized water until neutral. The carbon black was then dispersed in DMF and ultrasonically dispersed for 0.5 hours. 2 parts of benzoyl chloride were added, the temperature was raised to 60℃, and the reaction was stirred for 2 hours. The precipitate was then centrifuged, washed three times with deionized water, and dried at 75℃ to constant weight. The precipitate was then dispersed in DMAc, 0.1 parts of triethylamine were added, and the reaction was stirred for 1 hour. 4 parts of fluorosilicone modified intermediate were added, the temperature was raised to 85℃, and the reaction was stirred for 2 hours. The precipitate was then centrifuged and dried to constant weight to obtain fluorosilicone modified carbon black.

[0062] S13. By weight, 10 parts of fluorosilicone modified carbon black were dispersed in DMF and ultrasonically dispersed for 0.5 h. Then, 0.05 parts of tetra(triphenylphosphine)palladium were added and mixed for another 5 min. Butadiene was then introduced and the temperature was raised to 75 °C. The reaction pressure of butadiene was maintained at 0.5 MPa. After reacting for 4 h, the heating was stopped, the precipitate was separated by centrifugation, washed with deionized water, and vacuum dried for 12 h to obtain modified carbon black.

[0063] Comparative Example 1. A method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve, comprising the following steps:

[0064] Compared with Example 1, no modified carbon black was prepared in this comparative example;

[0065] S1. Preparation of oil-resistant rubber composite materials;

[0066] S11. By weight, after 100 parts of fluorosilicone rubber are milled and passed through the mill three times, 2 parts of activator and 1.5 parts of antioxidant are added, the mixture is heated to 75°C and mixed for 20 minutes, then 1.5 parts of plasticizer and 40 parts of carbon black are added, and the mixture is continued to be mixed for 15 minutes. Then 1.5 parts of vulcanizing agent are added, and the mixture is passed through the mill three times to obtain the compound.

[0067] S12. After the compounded rubber is left to stand at room temperature for 16 hours, it is heated to 170℃ for vulcanization. The vulcanization pressure is 10MPa and the vulcanization time is 10min. After vulcanization, an oil-resistant rubber composite material for fuel tank isolation valve is obtained.

[0068] Comparative Example 2. A method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve, comprising the following steps:

[0069] Compared with Example 1, this comparative example did not undergo step S13.

[0070] S1. Preparation of modified carbon black;

[0071] S11. By weight, 10 parts of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane were dispersed in tetrahydrofuran. After stirring and mixing for 0.5 h, under nitrogen atmosphere protection, 0.03 parts of aluminum chloride were added, and stirring and mixing were continued for 15 min to obtain a dispersion of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane.

[0072] Under a nitrogen atmosphere, 0.85 parts of 2,5-diaminotrifluorotoluene were dispersed in DMAc and ultrasonically mixed for 1 h. Then, 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane dispersion was added dropwise at room temperature for 2 h with continuous stirring. After the addition was completed, the solution was heated to 70 °C and stirred for 2 h. The excess solvent was removed by rotary evaporation. The product was washed once with deionized water and the remaining product was vacuum evaporated to constant weight to obtain the fluorosilicone modified intermediate.

[0073] S12. By weight, 10 parts of carbon black were dispersed in 68wt% concentrated nitric acid, heated to 55℃, and ultrasonically dispersed for 4 hours. After centrifugation to separate the precipitate, the precipitate was washed with deionized water until neutral. The carbon black was then dispersed in DMF and ultrasonically dispersed for 0.5 hours. 2 parts of benzoyl chloride were added, the temperature was raised to 60℃, and the reaction was stirred for 2 hours. The precipitate was then centrifuged, washed three times with deionized water, and dried at 75℃ to constant weight. The precipitate was then dispersed in DMAc, 0.1 parts of triethylamine were added, and the reaction was stirred for 1 hour. 0.5 parts of fluorosilicone modified intermediate were added, the temperature was raised to 85℃, and the reaction was stirred for 2 hours. The precipitate was then centrifuged and dried to constant weight to obtain fluorosilicone modified carbon black.

[0074] S2. Preparation of oil-resistant rubber composite materials;

[0075] S21. By weight, after 100 parts of fluorosilicone rubber are milled and passed through the mill three times, 2 parts of activator and 1.5 parts of antioxidant are added. After heating to 75°C and mixing for 20 minutes, 1.5 parts of plasticizer and 40 parts of fluorosilicone modified carbon black are added. After mixing for another 15 minutes, 1.5 parts of vulcanizing agent are added. After passing through the mill three times, the compound is obtained.

[0076] S22. After the compounded rubber is left to stand at room temperature for 16 hours, it is heated to 170℃ for vulcanization. The vulcanization pressure is 10MPa and the vulcanization time is 10min. After vulcanization, an oil-resistant rubber composite material for fuel tank isolation valve is obtained.

[0077] Testing: Shore hardness was tested on the samples prepared in Examples 1-4 and Comparative Examples 1-2 according to GB / T 531-2008; oil resistance was tested on the samples prepared in Examples 1-4 and Comparative Examples 1-2 according to GB / T 1690-2012, using No. 3 standard oil as the test standard; tensile strength and elongation at break were tested on the samples prepared in Examples 1-4 and Comparative Examples 1-2 according to GB / T 528-2009; after a thermo-oxidative aging test on the samples prepared in Examples 1-4 and Comparative Examples 1-2 according to GB / T 13939-2014, their tensile strength and elongation at break were tested again, with the test temperature at 135℃ and the time at 72h; the test results are shown in the table below.

[0078]

[0079] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. 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 method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve, characterized in that, Includes the following steps: S1. Preparation of modified carbon black; S11. Disperse 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane in tetrahydrofuran, stir and mix for 0.5-1 h, then under nitrogen atmosphere protection, add aluminum chloride, and continue stirring and mixing for 15-30 min to obtain a dispersion of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane; Under a nitrogen atmosphere, 2,5-diaminotrifluorotoluene was dispersed in DMAc and ultrasonically mixed for 1-2 hours. Then, 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane dispersion was added dropwise at room temperature with continuous stirring. After the addition was completed, the solution was heated to 70-75°C and stirred for 2-4 hours. Excess solvent was removed by rotary evaporation. The product was washed 1-3 times with deionized water, and the remaining product was vacuum evaporated to constant weight to obtain a fluorosilicone modified intermediate. S12. Disperse carbon black in concentrated nitric acid, heat to 55-65℃, and ultrasonically disperse for 2-6 hours. After centrifugation to separate the precipitate, wash the precipitate with deionized water until neutral. Disperse the carbon black in DMF, ultrasonically disperse for 0.5-1 hours, add benzoyl chloride, heat to 60-70℃, stir for 2-5 hours, centrifuge to separate the precipitate, wash the precipitate 3-5 times with deionized water, dry to constant weight at 70-80℃, disperse it in DMAc, add triethylamine, stir for 1-1.5 hours, add fluorosilicone modified intermediate, heat to 85-90℃, stir for 2-4 hours, centrifuge to separate the precipitate, and dry to constant weight to obtain fluorosilicone modified carbon black. S13. Disperse fluorosilicone modified carbon black in DMF, ultrasonically disperse for 0.5-1 h, add tetra(triphenylphosphine)palladium, continue mixing for 5-10 min, then introduce butadiene, heat to 75-85℃, maintain butadiene reaction pressure at 0.5-1.5 MPa, react for 1-6 h, then stop heating, centrifuge to separate the precipitate, wash with deionized water, and vacuum dry for 12-24 h to obtain modified carbon black; S2. Preparation of oil-resistant rubber composite materials; S21. After the fluorosilicone rubber is milled and passed through the mill 3-5 times, activator and antioxidant are added, the temperature is raised to 55-120℃ and mixed for 10-25 minutes, plasticizer and modified carbon black are added, and the mixture is continued to be mixed for 5-20 minutes. Then, vulcanizing agent is added, and the mixture is passed through the mill 3-5 times to obtain the compound. S22. After the rubber compound is left to stand at room temperature for 12-24 hours, it is heated and vulcanized to obtain an oil-resistant rubber composite material for fuel tank isolation valve.

2. The method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve according to claim 1, characterized in that: In step S11, by weight, the mass ratio of 1,1,3,3-tetramethyl-1,3-bis[3-(epoxyethylmethoxy)propyl]disiloxane, aluminum chloride, and 2,5-diaminotrifluorotoluene is 10:(0.03-0.05):(0.85-0.98).

3. The method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve according to claim 1, characterized in that: In step S12, the concentration of the concentrated nitric acid is 68-90 wt%.

4. The method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve according to claim 1, characterized in that: In step S12, the mass ratio of carbon black, benzoyl chloride, and triethylamine is 10:(2-4):(0.1-0.3).

5. The method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve according to claim 1, characterized in that: In step S12, the mass ratio of carbon black to fluorosilicone modified intermediate is 10:(0.5-4).

6. The method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve according to claim 1, characterized in that: In step S13, the mass ratio of the fluorosilicone modified carbon black to tetra(triphenylphosphine)palladium is 10:(0.03-0.08).

7. The method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve according to claim 1, characterized in that: In step S13, the mass ratio of the fluorosilicone modified carbon black to tetra(triphenylphosphine)palladium is 10:(0.03-0.08).

8. The method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve according to claim 1, characterized in that: By weight, in step S21, the compound consists of the following components: 100 parts fluorosilicone rubber, 40-55 parts modified carbon black, 1-8 parts activator, 0.5-3 parts antioxidant, 1-3 parts plasticizer, and 1-2.5 parts vulcanizing agent. Wherein, the activator is active zinc oxide; the antioxidant is any one of antioxidant 4010 and antioxidant RD; the plasticizer is a phthalate plasticizer; and the vulcanizing agent is dicumyl peroxide, benzoyl peroxide, or di-tert-butyl peroxide.

9. The method for preparing an oil-resistant rubber composite material for a fuel tank isolation valve according to claim 1, characterized in that: In step S22, the vulcanization temperature is 165-175℃, the vulcanization pressure is 10-15MPa, and the vulcanization time is 10-15min.

10. An oil-resistant rubber composite material for a fuel tank isolation valve prepared by the preparation method according to any one of claims 1-9.

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