High-temperature-resistant flame-retardant rubber cooling water hose and processing method and application thereof

Abstract

The application discloses a kind of high-temperature-resistant flame-retardant rubber cooling water hose and its processing method and application, it is related to rubber technical field, its preparation method includes the following steps: hydrogenated nitrile rubber, epoxy natural rubber is added in internal mixer according to proportion, heating and mixing, and the blend matrix is obtained;Blending matrix is added to internal mixer, acetonitrile suspension of modified graphene oxide nanosheet, acetonitrile suspension of modified nano-aluminum oxide is sequentially added, mixed, further modified aramid pulp, modified polyvinyl alcohol short fiber, modified aluminosilicate microsphere is added, and mixing, finally, crosslinking system is added, and the rubber compound is obtained;Rubber compound is injected into hose mold, vulcanization, and the vulcanized hose blank is obtained;The vulcanized hose blank is directionally stretched, heat preservation, and cooled to room temperature, and the high-temperature-resistant flame-retardant rubber cooling water hose is obtained.

Description

Technical Field

[0001] This invention relates to the field of rubber technology, specifically to a high-temperature resistant, flame-retardant rubber cooling water hose, its processing method, and its application. Background Technology

[0002] In the field of rubber technology, cooling water hoses are widely used in various cooling piping systems, but existing products have many performance shortcomings. Traditional rubber hoses have limited high-temperature resistance, are prone to aging and deformation under long-term exposure to high temperatures, and lack sufficient flame retardancy, posing safety risks under complex operating conditions. Simultaneously, the poor interfacial compatibility between the rubber matrix and various fillers leads to uneven internal structure of the composite material, making it difficult to simultaneously achieve optimal mechanical strength, crack resistance, and dimensional stability, thus affecting service life. Furthermore, existing processing techniques suffer from poor filler dispersion, complex modification methods, or high costs, making it difficult to achieve synergistic optimization of high-temperature resistance, flame retardancy, flexibility, and durability. This fails to meet the stringent requirements of cooling piping systems for comprehensive material performance, limiting their application in a wider range of scenarios. Summary of the Invention

[0003] The purpose of this invention is to provide a high-temperature resistant, flame-retardant rubber cooling water hose, its processing method, and its application, in order to solve the problems raised in the prior art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: A processing method for a high-temperature resistant and flame-retardant rubber cooling water hose includes the following steps: adding chopped aramid fiber slurry to a 30wt% phosphoric acid solution, heating to 55-60℃ for etching for 2-2.5h, filtering, washing to neutral, drying, further immersing in a 2wt% ethyl acetate solution of γ-methacryloyloxypropyltrimethoxysilane for hydrolysis for 1-1.5h, filtering, drying, and finally immersing in a 4wt% ethyl acetate solution of polymethylene polyphenyl polyisocyanate for soaking for 30-45min, and vacuum drying to obtain modified aramid slurry; In the preparation of modified aramid pulp, the mass ratio of chopped aramid fiber pulp: phosphoric acid solution: ethyl acetate solution of γ-methacryloyloxypropyltrimethoxysilane: ethyl acetate solution of polymethylene polyphenyl polyisocyanate is 1:(0.5-1.0):(0.05-0.1):(0.03-0.08); Polyvinyl alcohol short fibers were immersed in an ethanol solution of 3wt% γ-glycidyl etheroxypropyltrimethoxysilane, heated to 30-40℃ and kept at that temperature for 2-3 hours, filtered and dried to obtain modified polyvinyl alcohol short fibers. In the preparation of modified polyvinyl alcohol short fibers, the mass ratio of polyvinyl alcohol short fibers to γ-glycidoxypropyltrimethoxysilane ethanol solution is 1:(5-8). The polyvinyl alcohol short fibers have a diameter of 20-30 μm and a length of 1-2 mm; Graphene oxide was dispersed in an ammonia solution with a pH of 10.5-11, hydrazine was added, the mixture was stirred for 8-12 hours, and then dried under vacuum to obtain reduced graphene oxide. The reduced graphene oxide was then immersed in an ethanol solution of 2 wt% γ-methacryloyloxypropyltrimethoxysilane, ultrasonically dispersed, and dried to obtain modified graphene oxide nanosheets. In the preparation of modified graphene oxide nanosheets, the mass ratio of graphene oxide: hydrazine: γ-methacryloxypropyltrimethoxysilane in ethanol solution is 1:(0.01-0.02):(10-15). Nano-alumina was added to deionized water and ultrasonically dispersed. Then, 0.5-1 wt% of an ethanol solution of γ-aminopropyltriethoxysilane was added, and the mixture was heated to 50-60℃ and stirred for 2-3 hours. The mixture was then filtered and dried to obtain modified nano-alumina. In the preparation of modified nano-alumina, the mass ratio of nano-alumina to γ-aminopropyltriethoxysilane in ethanol solution is 1:(0.02-0.05). The nano-alumina particles have a diameter of 10 nm. Modified aluminosilicate microspheres were obtained by plasma treatment of the surface of aluminosilicate microspheres. During the preparation of modified aluminosilicate microspheres, the plasma treatment parameters were: discharge power of 300-305W and treatment time of 10-11min. The modified aluminosilicate microspheres have an ionic size of 20-100 μm and a wall thickness of 5-10% of their diameter. S1: Add hydrogenated nitrile rubber and epoxidized natural rubber to a mixer in proportion, heat to 80-85℃ and mix for 10-15 minutes to obtain a blend matrix; In the preparation of the blend matrix, the mass ratio of hydrogenated nitrile rubber to epoxidized natural rubber is (60-80):(20-40); The parameters of the hydrogenated nitrile rubber are: acrylonitrile content of 34wt% and Mooney viscosity (ML1+4, 100℃) of 63. The parameters for the epoxidized natural rubber are: an epoxidation degree of 25%; S2: Add the blended matrix to a mixer and heat it to 80-85℃. Then, add the acetonitrile suspension of modified graphene oxide nanosheets and the acetonitrile suspension of modified nano-alumina in sequence. Mix for 10-15 minutes. Then, add the modified aramid slurry, modified polyvinyl alcohol short fiber, and modified aluminosilicate microspheres. Mix for 30-40 minutes. Finally, add the crosslinking system and mix for 15-20 minutes to obtain the rubber compound. The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl 2-isocyanate acrylate, and 2-amino-4-hydroxy-6-methylpyrimidine in a mass ratio of (4-6):(1-2):(2-3):(1-2); The components of the rubber compound, by mass fraction, include: 95-100 parts of blend matrix, 3-5 parts of modified aramid paste, 3-5 parts of modified polyvinyl alcohol short fiber, 1-2 parts of modified graphene oxide nanosheets, 10-20 parts of modified nano-alumina, 3-10 parts of modified aluminosilicate microspheres, and 8-12 parts of crosslinking system. In the acetonitrile suspension of the modified graphene oxide nanosheets, the mass ratio of modified graphene oxide nanosheets to acetonitrile is 1:(10-15); in the acetonitrile suspension of the modified nano aluminum oxide, the mass ratio of modified nano aluminum oxide to acetonitrile is 1:(10-15). S3: Inject the rubber compound into the hose mold, vulcanize it to obtain a vulcanized hose blank; stretch the vulcanized hose blank in a specific direction, keep it warm, and cool it to room temperature to obtain a high-temperature resistant flame-retardant rubber cooling water hose. The vulcanization temperature is 175-180℃, the pressure is 10-12MPa, and the time is 1.5-2h; The directional stretching process involves applying a strain of 30-50% axially to the vulcanized hose blank and holding it for 48-50 hours. The insulation temperature is 200-205℃, and the time is 4-4.5h.

[0005] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention uses hydrogenated nitrile butadiene rubber (NBR) and epoxidized natural rubber in a specific ratio to obtain a blend matrix. The hydrogenated NBR, through selective hydrogenation, reduces unsaturated double bonds in its main chain, exhibiting excellent high-temperature resistance and oil aging resistance, providing a good foundation for the processing flow and mechanical strength of the hose. The epoxidized natural rubber can chemically react with the hydroxyl and amino groups on the modified filler surface, and its 25% epoxidation degree balances the rigidity and elasticity of the matrix, alleviating the brittleness problem when used alone. This results in a blend matrix that not only combines high-temperature resistance, oil resistance, and elasticity, providing reliable basic mechanical properties and environmental stability for the hose, but also significantly improves interfacial compatibility with various modified fillers, effectively reducing phase separation and ensuring the uniformity of the composite material's internal structure.

[0006] 2. The present invention prepares ① modified aramid paste, in which phosphoric acid forms grooves on the surface of etched fibers and introduces hydroxyl groups. Subsequently, silane coupling agent hydrolysis and condensation, and polyisocyanate react with rubber molecular chains, significantly improving the tensile strength, tear strength and high temperature deformation resistance of the hose, avoiding filler detachment at high temperature, and enhancing the long-term bonding stability with the rubber matrix. ② Modified polyvinyl alcohol short fiber: The epoxy groups of silane coupling agent KH560 react with the hydroxyl groups on the surface of polyvinyl alcohol, and at the same time form chemical bonds with the rubber matrix, improving compatibility. The polyvinyl alcohol fiber constructs a three-dimensional network in the matrix, which hinders molecular chain slippage, reduces high-temperature creep, and enhances oil aging resistance. It forms a dual-fiber reinforcement system with aramid pulp, taking into account both rigidity and toughness. ③ Modified graphene oxide nanosheets: The double bonds of the silane coupling agent participate in rubber vulcanization, enabling the graphene oxide nanosheets to chemically bond with the matrix. The technical effect is to construct a high-temperature resistant barrier network, reduce thermal conductivity, decrease linear combustion rate, synergistically enhance tensile strength and wear resistance, and inhibit flame spread; ④ Modified nano-alumina, with silane coupling agent KH550 improving the dispersibility of nano-alumina in the matrix, its high thermal conductivity uniformly transfers heat, forming an inorganic heat insulation layer at high temperatures. The technical effects are to avoid local overheating, improve high-temperature mechanical stability, synergistically enhance flame retardancy to increase coke residue rate, reduce combustion mass loss, and construct a dual system of thermal conductivity and insulation with aluminosilicate microspheres; ⑤ Modified aluminosilicate microspheres undergo low-temperature plasma treatment to clean the surface and introduce oxygen-containing polar groups, reducing the contact angle and enhancing wetting and adhesion to the rubber matrix; the hollow structure reduces thermal conductivity. The technical effects are reduced material density, extended heating time of unheated surfaces at high temperatures, improved tensile strength and crack resistance, and inhibition of crack propagation.

[0007] 3. The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl 2-isocyanate acrylate (and 2-amino-4-hydroxy-6-methylpyrimidine in a specific ratio). Its mechanism of action is the synergistic construction of a dual network of "covalent crosslinking + dynamic hydrogen bonding" by multiple components: peroxide F40 acts as the main crosslinking agent, decomposing under sulfidation to generate free radicals, initiating CC crosslinking of the blend matrix molecular chains to form a rigid crosslinking network; triallyl isocyanurate acts as a crosslinking aid, participating in the crosslinking reaction through polyunsaturated bonds, improving crosslinking efficiency and network density; the isocyanate groups of ethyl 2-isocyanate acrylate react with the amino and hydroxyl groups of 2-amino-4-hydroxy-6-methylpyrimidine to form carbonyl-amide double hydrogen bonds, constructing a dynamic crosslinking network that can reversibly break and recombine at high temperatures, releasing stress. This synergistic mechanism significantly improves the crosslinking density of the hose, taking into account both mechanical strength and elasticity at high temperatures, while introducing dynamic crosslinking points to improve the material's crack resistance and thermo-oxidative aging stability, avoiding the brittleness problem of traditional covalent crosslinking networks.

[0008] 4. This invention uses a directional stretching process to orient fillers such as aramid pulp, polyvinyl alcohol fiber, and graphene oxide nanosheets axially, forming an oriented reinforcing structure that improves the axial tensile strength and fatigue resistance of the hose. Simultaneously, it induces cross-linked network recombination, reducing internal defects. The heat preservation process further promotes interfacial reactions and cross-linking, improving the uniformity of cross-linking density. It also simulates a high-temperature service environment, releasing internal stress in advance and reducing dimensional deformation during actual use. The synergistic effect of this series of processes optimizes the filler arrangement and cross-linking structure, maximizing the performance of each component and ultimately achieving a comprehensive technical effect of high-temperature resistance, flame retardancy, high strength, and dimensional stability in the hose. Detailed Implementation

[0009] 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.

[0010] Short-cut aramid fiber slurry was added to a 30wt% phosphoric acid solution, heated to 55℃ for etching for 2h, filtered, washed until neutral, dried, and further immersed in a 2wt% ethyl acetate solution of γ-methacryloyloxypropyltrimethoxysilane for hydrolysis for 1h, filtered, dried, and finally immersed in a 4wt% ethyl acetate solution of polymethylene polyphenyl polyisocyanate for 30min, and vacuum dried to obtain modified aramid slurry. In the preparation of modified aramid pulp, the mass ratio of chopped aramid fiber pulp: phosphoric acid solution: ethyl acetate solution of γ-methacryloyloxypropyltrimethoxysilane: ethyl acetate solution of polymethylene polyphenyl polyisocyanate is 1:0.75:0.075:0.06. Polyvinyl alcohol short fibers were immersed in an ethanol solution of 3wt% γ-glycidyl etheroxypropyltrimethoxysilane, heated to 30°C and kept at that temperature for 2 hours, filtered and dried to obtain modified polyvinyl alcohol short fibers. In the preparation of modified polyvinyl alcohol short fibers, the mass ratio of polyvinyl alcohol short fibers to γ-glycidoxypropyltrimethoxysilane ethanol solution is 1:6. The polyvinyl alcohol short fibers have a diameter of 20 μm and a length of 1 mm; Graphene oxide was dispersed in an ammonia solution at pH 10.5, hydrazine was added, the mixture was stirred for 8 hours, and then dried under vacuum to obtain reduced graphene oxide. The reduced graphene oxide was then immersed in an ethanol solution of 2 wt% γ-methacryloyloxypropyltrimethoxysilane, ultrasonically dispersed, and dried to obtain modified graphene oxide nanosheets. In the preparation of modified graphene oxide nanosheets, the mass ratio of graphene oxide: hydrazine: γ-methacryloxypropyltrimethoxysilane in ethanol solution is 1:0.01:10. Nano-alumina was added to deionized water and ultrasonically dispersed. Then, 0.5-1 wt% of an ethanol solution of γ-aminopropyltriethoxysilane was added, heated to 50°C and stirred for 2 hours. The mixture was then filtered and dried to obtain modified nano-alumina. In the preparation of modified nano-alumina, the mass ratio of nano-alumina to γ-aminopropyltriethoxysilane in ethanol solution is 1:0.03. The nano-alumina particles have a diameter of 10 nm. Modified aluminosilicate microspheres were obtained by plasma treatment of the surface of aluminosilicate microspheres. In the preparation of modified aluminosilicate microspheres, the plasma treatment parameters were: discharge power of 300W and treatment time of 10min. The modified aluminosilicate microspheres have an ionic size of 50 μm and a wall thickness of 8% of their diameter. Example 1: A processing method for a high-temperature resistant flame-retardant rubber cooling water hose: S1: Hydrogenated nitrile rubber and epoxidized natural rubber are added to a mixer in proportion, heated to 80°C and mixed for 10 minutes to obtain a blend matrix; In the preparation of the blend matrix, the mass ratio of hydrogenated nitrile rubber to epoxidized natural rubber is 70:30; S2: Add 100 parts of the blend matrix to a mixer and heat to 80°C. Then, add acetonitrile suspension containing 1.5 parts of modified graphene oxide nanosheets and acetonitrile suspension containing 15 parts of modified nano-alumina in sequence. Mix for 10 minutes. Then, add 4 parts of modified aramid paste, 4 parts of modified polyvinyl alcohol short fiber, and 6 parts of modified aluminosilicate microspheres. Mix for 30 minutes. Finally, add 10 parts of the crosslinking system and mix for 15 minutes to obtain the rubber compound. The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl isocyanate acrylate, and 2-amino-4-hydroxy-6-methylpyrimidine in a mass ratio of 5:1.5:2.5:1. S3: Inject the rubber compound into the hose mold, vulcanize at 175℃ and 10MPa for 1.5h to obtain a vulcanized hose blank; apply 30% strain along the axial direction to the vulcanized hose blank, maintain for 48h, keep at 200℃ for 4h, and cool to room temperature to obtain a high-temperature resistant flame-retardant rubber cooling water hose.

[0011] Example 2: A processing method for a high-temperature resistant flame-retardant rubber cooling water hose: S1: Hydrogenated nitrile rubber and epoxidized natural rubber are added to a mixer in proportion, heated to 80°C and mixed for 10 minutes to obtain a blend matrix; In the preparation of the blend matrix, the mass ratio of hydrogenated nitrile rubber to epoxidized natural rubber is 60:40; S2: Add 100 parts of the blend matrix to a mixer and heat to 80°C. Then, add acetonitrile suspension containing 1 part of modified graphene oxide nanosheets and acetonitrile suspension containing 15 parts of modified nano-alumina in sequence. Mix for 10 minutes. Then, add 3 parts of modified aramid paste, 4 parts of modified polyvinyl alcohol short fiber, and 6 parts of modified aluminosilicate microspheres. Mix for 30 minutes. Finally, add 10 parts of the crosslinking system and mix for 15 minutes to obtain the rubber compound. The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl isocyanate acrylate, and 2-amino-4-hydroxy-6-methylpyrimidine in a mass ratio of 5:1.5:2.5:1. S3: Inject the rubber compound into the hose mold, vulcanize at 175℃ and 10MPa for 1.5h to obtain a vulcanized hose blank; apply 30% strain along the axial direction to the vulcanized hose blank, maintain for 48h, keep at 200℃ for 4h, and cool to room temperature to obtain a high-temperature resistant flame-retardant rubber cooling water hose.

[0012] Example 3: A processing method for a high-temperature resistant flame-retardant rubber cooling water hose: S1: Hydrogenated nitrile rubber and epoxidized natural rubber are added to a mixer in proportion, heated to 80°C and mixed for 10 minutes to obtain a blend matrix; In the preparation of the blend matrix, the mass ratio of hydrogenated nitrile rubber to epoxidized natural rubber is 80:20; S2: Add 100 parts of the blend matrix to a mixer and heat to 80°C. Then, add acetonitrile suspension containing 2 parts of modified graphene oxide nanosheets and acetonitrile suspension containing 20 parts of modified nano-alumina in sequence. Mix for 10 minutes. Then, add 5 parts of modified aramid paste, 4 parts of modified polyvinyl alcohol short fiber, and 10 parts of modified aluminosilicate microspheres. Mix for 30 minutes. Finally, add 12 parts of the crosslinking system and mix for 15 minutes to obtain the rubber compound. The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl isocyanate acrylate, and 2-amino-4-hydroxy-6-methylpyrimidine in a mass ratio of 5:1.5:2.5:1. S3: Inject the rubber compound into the hose mold, vulcanize at 175℃ and 10MPa for 1.5h to obtain a vulcanized hose blank; apply 40% strain along the axial direction to the vulcanized hose blank, maintain for 48h, keep at 200℃ for 4h, and cool to room temperature to obtain a high-temperature resistant flame-retardant rubber cooling water hose.

[0013] Example 4: A processing method for a high-temperature resistant flame-retardant rubber cooling water hose: S1: Hydrogenated nitrile rubber and epoxidized natural rubber are added to a mixer in proportion, heated to 80°C and mixed for 10 minutes to obtain a blend matrix; In the preparation of the blend matrix, the mass ratio of hydrogenated nitrile rubber to epoxidized natural rubber is 70:30; S2: Add 100 parts of the blend matrix to a mixer and heat to 80°C. Then, add acetonitrile suspension containing 1.5 parts of modified graphene oxide nanosheets and acetonitrile suspension containing 15 parts of modified nano-alumina in sequence. Mix for 10 minutes. Then, add 5 parts of modified aramid paste, 5 parts of modified polyvinyl alcohol short fiber, and 6 parts of modified aluminosilicate microspheres. Mix for 30 minutes. Finally, add 10 parts of the crosslinking system and mix for 15 minutes to obtain the rubber compound. The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl isocyanate acrylate, and 2-amino-4-hydroxy-6-methylpyrimidine in a mass ratio of 5:1.5:2.5:1. S3: Inject the rubber compound into the hose mold, vulcanize at 175℃ and 10MPa for 1.5h to obtain a vulcanized hose blank; apply 50% strain along the axial direction to the vulcanized hose blank, maintain for 48h, keep at 200℃ for 4h, and cool to room temperature to obtain a high-temperature resistant flame-retardant rubber cooling water hose.

[0014] Comparative Example 1: A processing method for a high-temperature resistant flame-retardant rubber cooling water hose: S1: Hydrogenated nitrile rubber and epoxidized natural rubber are added to a mixer in proportion, heated to 80°C and mixed for 10 minutes to obtain a blend matrix; In the preparation of the blend matrix, the mass ratio of hydrogenated nitrile rubber to epoxidized natural rubber is 70:30; S2: Add 100 parts of the blend matrix to a mixer, heat to 80°C, add acetonitrile suspension containing 15 parts of modified nano aluminum oxide, mix for 10 min, add 10 parts of the crosslinking system, mix for 15 min, and obtain rubber compound. The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl isocyanate acrylate, and 2-amino-4-hydroxy-6-methylpyrimidine in a mass ratio of 5:1.5:2.5:1. S3: Inject the rubber compound into the hose mold, vulcanize at 175℃ and 10MPa for 1.5h to obtain a vulcanized hose blank; apply 30% strain along the axial direction to the vulcanized hose blank, maintain for 48h, keep at 200℃ for 4h, and cool to room temperature to obtain a high-temperature resistant flame-retardant rubber cooling water hose.

[0015] Comparative Example 2: A processing method for a high-temperature resistant flame-retardant rubber cooling water hose: S1: Hydrogenated nitrile rubber and epoxidized natural rubber are added to a mixer in proportion, heated to 80°C and mixed for 10 minutes to obtain a blend matrix; In the preparation of the blend matrix, the mass ratio of hydrogenated nitrile rubber to epoxidized natural rubber is 70:30; S2: Add 100 parts of the blend matrix to a mixer and heat to 80°C. Then, add acetonitrile suspension containing 1.5 parts of graphene oxide nanosheets and acetonitrile suspension containing 15 parts of nano-alumina in sequence. Mix for 10 minutes. Then, add 4 parts of aramid paste, 4 parts of polyvinyl alcohol short fiber, and 6 parts of aluminosilicate microspheres. Mix for 30 minutes. Finally, add 10 parts of the crosslinking system and mix for 15 minutes to obtain the rubber compound. The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl isocyanate acrylate, and 2-amino-4-hydroxy-6-methylpyrimidine in a mass ratio of 5:1.5:2.5:1. S3: Inject the rubber compound into the hose mold, vulcanize at 175℃ and 10MPa for 1.5h to obtain a vulcanized hose blank; apply 30% strain along the axial direction to the vulcanized hose blank, maintain for 48h, keep at 200℃ for 4h, and cool to room temperature to obtain a high-temperature resistant flame-retardant rubber cooling water hose.

[0016] Comparative Example 3: A processing method for a high-temperature resistant flame-retardant rubber cooling water hose: S1: Hydrogenated nitrile rubber and epoxidized natural rubber are added to a mixer in proportion, heated to 80°C and mixed for 10 minutes to obtain a blend matrix; In the preparation of the blend matrix, the mass ratio of hydrogenated nitrile rubber to epoxidized natural rubber is 90:10; S2: Add 100 parts of the blend matrix to a mixer and heat to 80°C. Then, add acetonitrile suspension containing 1.5 parts of modified graphene oxide nanosheets and acetonitrile suspension containing 15 parts of modified nano-alumina in sequence. Mix for 10 minutes. Then, add 4 parts of modified aramid paste, 4 parts of modified polyvinyl alcohol short fiber, and 6 parts of modified aluminosilicate microspheres. Mix for 30 minutes. Finally, add 10 parts of the crosslinking system and mix for 15 minutes to obtain the rubber compound. The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl isocyanate acrylate, and 2-amino-4-hydroxy-6-methylpyrimidine in a mass ratio of 5:1.5:2.5:1. S3: Inject the rubber compound into the hose mold, vulcanize at 175℃ and 10MPa for 1.5h to obtain a vulcanized hose blank; apply 30% strain along the axial direction to the vulcanized hose blank, maintain for 48h, keep at 200℃ for 4h, and cool to room temperature to obtain a high-temperature resistant flame-retardant rubber cooling water hose.

[0017] Comparative Example 4: A processing method for a high-temperature resistant and flame-retardant rubber cooling water hose: S1: Hydrogenated nitrile rubber and epoxidized natural rubber are added to a mixer in proportion, heated to 80°C and mixed for 10 minutes to obtain a blend matrix; In the preparation of the blend matrix, the mass ratio of hydrogenated nitrile rubber to epoxidized natural rubber is 70:30; S2: Add 100 parts of the blend matrix to a mixer and heat to 80°C. Then, add acetonitrile suspension containing 1.5 parts of modified graphene oxide nanosheets and acetonitrile suspension containing 15 parts of modified nano-alumina in sequence. Mix for 10 minutes. Then, add 4 parts of modified aramid paste, 4 parts of modified polyvinyl alcohol short fiber, and 6 parts of modified aluminosilicate microspheres. Mix for 30 minutes. Finally, add 10 parts of the crosslinking system and mix for 15 minutes to obtain the rubber compound. The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl isocyanate acrylate, and 2-amino-4-hydroxy-6-methylpyrimidine in a mass ratio of 5:1.5:2.5:1. S3: Inject the rubber compound into the hose mold, vulcanize at 175℃ and 10MPa for 1.5h to obtain a vulcanized hose blank; keep it at 200℃ for 4h, and cool it to room temperature to obtain a high-temperature resistant flame-retardant rubber cooling water hose.

[0018] Testing: Mechanical property testing: Tensile testing was conducted according to ASTM D412, with a parameter of 500 mm / min; tear testing was conducted according to ASTM D624, with test temperatures of room temperature and 150℃. High temperature stability test: The tensile strength / tear strength retention rate was tested after 72 hours of heat treatment in a thermal aging chamber. Flame retardant performance test: The oxygen index of the hose was tested according to GB / T 2406; The experimental results are shown in Table 1 below.

[0019] Table 1 Performance Tests of Rubber Cooling Water Hose

[0020] Conclusion: The rubber cooling water hose prepared by this invention has excellent mechanical properties, thermal stability and flame retardant properties.

[0021] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A processing method for a high-temperature resistant, flame-retardant rubber cooling water hose, characterized in that: Includes the following steps: S1: Add hydrogenated nitrile rubber and epoxidized natural rubber to a mixer in proportion, heat to 80-85℃ and mix to obtain a blend matrix; S2: Add the blended matrix to a mixer and heat it to 80-85℃. Then, add the acetonitrile suspension of modified graphene oxide nanosheets and the acetonitrile suspension of modified nano-alumina in sequence, mix, and then add the modified aramid paste, modified polyvinyl alcohol short fiber, and modified aluminosilicate microspheres. Mix and finally add the crosslinking system to obtain the rubber compound. S3: Inject the rubber compound into the hose mold, vulcanize it to obtain a vulcanized hose blank; stretch the vulcanized hose blank in a specific direction, keep it warm, and cool it to room temperature to obtain a high-temperature resistant flame-retardant rubber cooling water hose.

2. The processing method of a high-temperature resistant flame-retardant rubber cooling water hose according to claim 1, characterized in that: The preparation method of the modified aramid slurry includes the following steps: adding chopped aramid fiber slurry to a 30-35wt% phosphoric acid solution, heating to 55-60℃ for etching for 2-2.5h, filtering, washing to neutral, drying, further immersing in a 2-2.5wt% ethyl acetate solution of γ-methacryloyloxypropyltrimethoxysilane for hydrolysis for 1-1.5h, filtering, drying, and finally immersing in a 4-5wt% ethyl acetate solution of polymethylene polyphenyl polyisocyanate for soaking for 30-45min, and vacuum drying to obtain the modified aramid slurry; In the preparation of modified aramid pulp, the mass ratio of chopped aramid fiber pulp: phosphoric acid solution: ethyl acetate solution of γ-methacryloyloxypropyltrimethoxysilane: ethyl acetate solution of polymethylene polyphenyl polyisocyanate is 1:(0.5-1.0):(0.05-0.1):(0.03-0.08).

3. The processing method of a high-temperature resistant flame-retardant rubber cooling water hose according to claim 1, characterized in that: The method for preparing the modified polyvinyl alcohol short fiber includes the following steps: immersing the polyvinyl alcohol short fiber in an ethanol solution of 3wt% γ-glycidyl etheroxypropyltrimethoxysilane, heating to 30-40℃ and holding for 2-3 hours, filtering, and drying to obtain the modified polyvinyl alcohol short fiber. In the preparation of modified polyvinyl alcohol short fibers, the mass ratio of polyvinyl alcohol short fibers to γ-glycidoxypropyltrimethoxysilane ethanol solution is 1:(5-8).

4. The processing method of a high-temperature resistant flame-retardant rubber cooling water hose according to claim 1, characterized in that: The method for preparing the modified graphene oxide nanosheets includes the following steps: dispersing graphene oxide in an ammonia solution with a pH of 10.5-11, adding hydrazine, stirring for 8-12 hours, and vacuum drying to obtain reduced graphene oxide; immersing the reduced graphene oxide in an ethanol solution of 2wt% γ-methacryloyloxypropyltrimethoxysilane, ultrasonically dispersing, and drying to obtain modified graphene oxide nanosheets. In the preparation of modified graphene oxide nanosheets, the mass ratio of graphene oxide: hydrazine: γ-methacryloxypropyltrimethoxysilane in ethanol solution is 1:(0.01-0.02):(10-15).

5. The processing method of a high-temperature resistant flame-retardant rubber cooling water hose according to claim 1, characterized in that: The method for preparing the modified nano-alumina includes the following steps: adding nano-alumina to deionized water, ultrasonically dispersing, adding 0.5-1wt% of an ethanol solution of γ-aminopropyltriethoxysilane, heating to 50-60℃ and stirring for 2-3 hours, filtering, and drying to obtain modified nano-alumina. In the preparation of modified nano-alumina, the mass ratio of nano-alumina to γ-aminopropyltriethoxysilane ethanol solution is 1:(0.02-0.05).

6. The processing method of a high-temperature resistant flame-retardant rubber cooling water hose according to claim 1, characterized in that: The method for preparing the modified aluminosilicate microspheres includes the following steps: subjecting the surface of the aluminosilicate microspheres to plasma treatment to obtain the modified aluminosilicate microspheres; In the preparation of modified aluminosilicate microspheres, the plasma treatment parameters were: discharge power of 300-305W and treatment time of 10-11min.

7. The processing method of a high-temperature resistant flame-retardant rubber cooling water hose according to claim 1, characterized in that: In the preparation of the blend matrix, the mass ratio of hydrogenated nitrile rubber to epoxidized natural rubber is (60-80):(20-40).

8. The processing method of a high-temperature resistant flame-retardant rubber cooling water hose according to claim 1, characterized in that: The crosslinking system is composed of peroxide F40, triallyl isocyanurate, ethyl 2-isocyanate acrylate, and 2-amino-4-hydroxy-6-methylpyrimidine in a mass ratio of (4-6):(1-2):(2-3):(1-2); The components of the rubber compound, by mass fraction, include: 95-100 parts of blend matrix, 3-5 parts of modified aramid paste, 3-5 parts of modified polyvinyl alcohol short fiber, 1-2 parts of modified graphene oxide nanosheets, 10-20 parts of modified nano-alumina, 3-10 parts of modified aluminosilicate microspheres, and 8-12 parts of crosslinking system.

9. A high-temperature resistant flame-retardant rubber cooling water hose prepared by the processing method of a high-temperature resistant flame-retardant rubber cooling water hose according to any one of claims 1-8.

10. An application of a high-temperature resistant, flame-retardant rubber cooling water hose, characterized in that: The application of the high-temperature resistant and flame-retardant rubber cooling water hose prepared by the processing method of the high-temperature resistant and flame-retardant rubber cooling water hose according to claim 9 in the cooling pipeline system.

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