Multi-component composite elastomer material for track floating slab and preparation method of multi-component composite elastomer material

Abstract

The invention discloses a multi-element composite elastomer material for a track floating slab and a preparation method of the multi-element composite elastomer material, and belongs to the technical field of rubber and plastic composite materials of track traffic accessories. The multi-element composite elastomer material is prepared from the following raw materials in parts by weight: 25 to 40 parts of nitrile rubber, 15 to 25 parts of ethylene propylene diene monomer, 5 to 10 parts of modified ethylene propylene diene monomer, 10 to 15 parts of maleic anhydride grafted chlorosulfonated polyethylene, 15 to 25 parts of polypropylene, 20 to 30 parts of carbon black, 10 to 15 parts of modified multi-walled carbon nanotubes, 2 to 5 parts of hollow fibers, 10 to 15 parts of paraffin oil, 0.8 to 1.6 parts of an oxidizing agent, 0.7 to 1.2 parts of an active agent, 0.5 to 1.1 parts of an anti-aging agent and 0.9 to 1.7 parts of a coupling agent. 0.95 to 2.25 parts of an accelerant and 0.2 to 0.6 part of a vulcanizing agent. According to the multi-element composite elastomer material provided by the invention, the nitrile rubber and ethylene propylene diene monomer blended rubber is taken as a main body, and the modified ethylene propylene diene monomer and the maleic anhydride grafted chlorosulfonated polyethylene are introduced for blending modification, so that the compatibility of the blended rubber is improved, and the strength and the wear resistance of the material are improved; the ozone resistance, the weather resistance and the low-temperature elasticity are excellent.

Description

Technical Field

[0001] This invention relates to the field of rubber and plastic composite materials for rail transit components, specifically to a multi-component composite elastomer material for rail floating slabs and its preparation method. Background Technology

[0002] Rail transit (including high-speed rail, subways, and intercity trains) serves as a vital transportation artery for modern cities and nations, and the safety, smoothness, comfort, and reliability of its operation are of paramount importance. During high-speed operation, vehicles inevitably generate continuous vibrations and impacts. These vibrations and impacts not only affect passenger comfort but are also transmitted to critical vehicle components (such as bogies, car bodies, and suspension systems) and the track structure. Long-term effects accelerate component fatigue damage, shorten service life, increase maintenance costs, and even threaten operational safety. Therefore, high-performance damping and cushioning materials play a crucial role in the rail transit field and are widely used in floating slab systems, track fastening systems, and car body connection components.

[0003] Currently, the commonly used elastomer materials for vibration damping components in rail transit mainly include natural rubber (NR), neoprene rubber (CR), ethylene propylene diene monomer (EPDM), and nitrile butadiene rubber (NBR). While these materials each have their advantages, they still have significant limitations in meeting the increasingly stringent comprehensive performance requirements of rail transit, as manifested in the following ways:

[0004] Insufficient weather resistance and ozone resistance: Rail transit vehicles are exposed to harsh environments such as sunlight, rain, ozone, and extreme temperature changes for extended periods. Rubbers with a high number of double bonds, such as NR and NBR, have poor ozone aging resistance and weather resistance, making them prone to cracking, hardening, and loss of elasticity, leading to vibration damping failure. Although EPDM has excellent weather resistance and ozone resistance, when used alone or as the main component, other key properties (such as oil resistance) are often insufficient.

[0005] Limitations in oil and solvent resistance: Vehicle operating environments contain oils and solvents such as lubricating oil, hydraulic oil, and cleaning agents. NR and EPDM have poor oil resistance and are prone to swelling and deterioration. NBR has become an important choice due to its good oil resistance, but its weather resistance, ozone resistance, and low-temperature performance are relatively weak.

[0006] Low-temperature elasticity and cold resistance challenges: When operating in cold regions or during winter, cushioning materials must maintain good elastic modulus and damping properties to avoid hardening and embrittlement due to excessively high glass transition temperatures, thus losing their vibration damping function. The low-temperature performance of NBR and CR is generally inferior to that of EPDM.

[0007] High requirements for wear resistance and fatigue life: The buffer and vibration damping components are subjected to high frequency and large amplitude dynamic compression and shear stress during vehicle operation, which puts forward extremely high requirements for the wear resistance and dynamic fatigue life of the materials.

[0008] Single rubber materials struggle to maintain stable mechanical properties and dimensional stability under long-term dynamic loads because achieving a balance of comprehensive performance is difficult. Existing material systems often fail to achieve an ideal balance among key performance indicators such as oil resistance (NBR's advantage), weather / ozone resistance (EPDM's advantage), low-temperature elasticity (EPDM's advantage), high abrasion resistance, and good mechanical strength and elastic recovery. For example, using NBR alone results in good oil resistance but insufficient weather resistance, ozone resistance, and low-temperature performance. Using EPDM alone offers excellent weather resistance, ozone resistance, and low-temperature performance but poor oil resistance.

[0009] Simple blends often struggle to maintain stable mechanical properties and dimensional stability under long-term dynamic loads. For example, consider NBR / EPDM blends: EPDM is a low-unsaturated non-polar rubber with a saturated main chain and unsaturated side chains, exhibiting excellent resistance to chemical media, ozone aging, weathering, and flexural cracking. NBR, on the other hand, is a polar rubber with an unsaturated main chain, offering good resistance to non-polar media and antistatic properties. Furthermore, as the acrylonitrile (ACN) content increases, the polarity and antistatic properties of NBR improve.

[0010] Because NBR and EPDM have significantly different polarities, they are not compatible. Filler particles tend to agglomerate, and the rubber two-phase interface is prone to delamination. Therefore, NBR / EPDM blends are prone to problems of poor compatibility and phase separation, resulting in a significant decrease in mechanical properties (especially strength and abrasion resistance). Summary of the Invention

[0011] The purpose of this invention is to provide a multi-component composite elastomer material for track floating slabs and its preparation method, which solves the problem that NBR / EPDM blends are prone to poor compatibility and phase separation, leading to a significant decrease in mechanical properties (especially strength and wear resistance).

[0012] This invention is achieved through the following technical solution:

[0013] This invention provides a multi-component composite elastomer material for track floating slabs, comprising the following raw materials in parts by weight: 25-40 parts of nitrile rubber, 15-25 parts of ethylene propylene diene monomer (EPDM) rubber, 5-10 parts of modified EPDM rubber, 10-15 parts of maleic anhydride-grafted chlorosulfonated polyethylene, 15-25 parts of polypropylene, 20-30 parts of carbon black, 10-15 parts of modified multi-walled carbon nanotubes, 2-5 parts of hollow fiber, 10-15 parts of paraffin oil, 0.8-1.6 parts of oxidant, 0.7-1.2 parts of activator, 0.5-1.1 parts of antioxidant, 0.9-1.7 parts of coupling agent, 0.95-2.25 parts of accelerator, and 0.2-0.6 parts of vulcanizing agent.

[0014] Further specifying, in the multi-component composite elastomer material for the track floating plate, the preparation of the modified EPDM rubber includes:

[0015] EPDM rubber is heated to 140~170℃, and zinc methacrylate, glycidyl methacrylate and allyl (3-isocyanate-4-tolyl) carbamate are added sequentially to carry out a melt reaction. The modified EPDM rubber is obtained by extrusion.

[0016] The modified EPDM rubber comprises the following raw materials in parts by weight: 15-20 parts of EPDM rubber, 0.2-1 parts of zinc methacrylate, 1-2 parts of glycidyl methacrylate, and 1-2 parts of allyl (3-isocyanate-4-tolyl) carbamate.

[0017] Further specifying, in the multi-component composite elastomer material for the track floating plate, the preparation of the maleic anhydride-grafted chlorosulfonated polyethylene includes:

[0018] After mixing chlorosulfonated polyethylene and maleic anhydride evenly, dicumyl peroxide is added and stirring is continued for 5-10 minutes to obtain the maleic anhydride-grafted chlorosulfonated polyethylene.

[0019] The maleic anhydride-grafted chlorosulfonated polyethylene comprises the following raw materials in parts by weight: 20-30 parts of chlorosulfonated polyethylene, 10-20 parts of maleic anhydride, and 0.1-0.5 parts of dicumyl peroxide;

[0020] The grafting rate of the maleic anhydride-grafted chlorosulfonated polyethylene is 2-2.5%.

[0021] Further specifying, in the multi-component composite elastomer material for the track floating plate, the preparation of the modified multi-walled carbon nanotubes includes:

[0022] Gallic acid was dissolved in Tris hydrochloric acid buffer at pH 8-9. Multi-walled carbon nanotubes were added at a mass ratio of gallic acid to multi-walled carbon nanotubes of 1:(3-5). The mixture was ultrasonically dispersed at 40-50℃ for 5-7 hours, and then stirred at room temperature for 2-4 hours. After filtration and washing, the modified multi-walled carbon nanotubes were obtained.

[0023] Further specifying, in the multi-component composite elastomer material for the track floating plate, the multi-component composite elastomer material satisfies at least one of the following:

[0024] The oxidant is zinc oxide; the activator is stearic acid; and the coupling agent is Si-69.

[0025] More specifically, in the multi-component composite elastomer material for the track floating plate, the antioxidant is a composition containing 0.2 to 0.4 parts by weight of 2,2,4-trimethyl-1,2-dihydroquinoline polymer and 0.3 to 0.7 parts by weight of N-cyclohexyl-N'-phenyl-p-phenylenediamine.

[0026] More specifically, in the multi-component composite elastomer material for track floating plates, the accelerator is a composition containing 0.4 to 0.8 parts by weight of zinc dibutyldithiocarbamate, 0.2 to 0.5 parts by weight of accelerator dithiopyrophosphate, 0.2 to 0.6 parts by weight of dibenzothiazole disulfide, and 0.15 to 0.35 parts by weight of N-cyclohexyl-2-benzothiazole sulfenamide.

[0027] More specifically, in the multi-component composite elastomer material for the track floating plate, the vulcanizing agent is sulfur.

[0028] This invention also provides a method for preparing a multi-component composite elastomer material for track floating slabs. The preparation method uses the aforementioned multi-component composite elastomer material for track floating slabs and includes the following steps:

[0029] Nitrile rubber, ethylene propylene diene monomer (EPDM) rubber and polypropylene are mixed and left to stand for at least 8 hours. Then, modified EPDM rubber and maleic anhydride-grafted chlorosulfonated polyethylene are added and mixed again to obtain a multi-component composite elastomer plasticized rubber.

[0030] Carbon black, modified multi-walled carbon nanotubes, hollow fibers, paraffin oil, oxidant, activator, antioxidant, coupling agent, accelerator and vulcanizing agent are added to the multi-component composite elastomer plasticized rubber, and after mixing and pressing, a semi-finished rubber raw material is obtained.

[0031] The semi-finished rubber raw material is vulcanized by compression molding to obtain the multi-component composite elastomer material.

[0032] Further specifying, in the method for preparing the multi-component composite elastomer material for track floating plates, the vulcanization treatment employs a staged, gradual cooling process, including:

[0033] In the first vulcanization stage, the vulcanization temperature is 130–160℃, the time is 100–600s, and the vulcanization pressure is 5–12MPa.

[0034] The third vulcanization stage involves a vulcanization temperature of 120–150℃, a vulcanization time of 100–600s, and a vulcanization pressure of 5–12MPa.

[0035] The third vulcanization stage involves a vulcanization temperature of 110–140℃, a vulcanization time of 100–600s, and a vulcanization pressure of 5–12MPa.

[0036] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0037] The multi-component composite elastomer material provided by this invention is based on a blend of nitrile rubber and ethylene propylene diene monomer (EPDM) rubber. Through the introduction of modified EPDM rubber and maleic anhydride-grafted chlorosulfonated polyethylene for blending modification, the material composition and ratio are optimized, effectively solving the incompatibility problem between nitrile rubber and EPDM rubber, improving the compatibility of the blend, thereby enhancing the material's strength and wear resistance. Furthermore, it exhibits excellent ozone resistance, weather resistance, and low-temperature elasticity, ensuring that rail transit damping components can effectively resist aging cracking and low-temperature embrittlement during long-term service in harsh outdoor environments, maintaining stable performance and significantly extending service life. This material can provide durable, reliable, and efficient damping capabilities for high-speed rail vehicles, ensuring driving safety and comfort, and is particularly suitable for critical components subjected to high-frequency, high-load impacts. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0039] Figure 1 This is a schematic diagram of the steel spring shock-absorbing support in the track floating plate provided by the present invention.

[0040] In the diagram, 1-upper support plate; 2-spring; 3-lower support plate. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and accompanying drawings. The illustrative embodiments and descriptions of this invention are for explanation only and are not intended to limit the invention. Unless otherwise specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0042] To address the problems of poor compatibility and phase separation in existing NBR / EPDM blends, which lead to a significant decrease in mechanical properties (especially strength and abrasion resistance), this invention provides the following solution:

[0043] A multi-component composite elastomer material for use in track floating slabs comprises the following raw materials in parts by weight: 25-40 parts of nitrile rubber, 15-25 parts of ethylene propylene diene monomer (EPDM) rubber, 5-10 parts of modified EPDM rubber, 10-15 parts of maleic anhydride-grafted chlorosulfonated polyethylene, 15-25 parts of polypropylene, 20-30 parts of carbon black, 10-15 parts of modified multi-walled carbon nanotubes, 2-5 parts of hollow fiber, 10-15 parts of paraffin oil, 0.8-1.6 parts of oxidant, 0.7-1.2 parts of activator, 0.5-1.1 parts of antioxidant, 0.9-1.7 parts of coupling agent, 0.95-2.25 parts of accelerator, and 0.2-0.6 parts of vulcanizing agent.

[0044] The multi-component composite elastomer material provided by this invention is based on a blend of nitrile rubber and ethylene propylene diene monomer (EPDM) rubber. Through the introduction of modified EPDM rubber and maleic anhydride-grafted chlorosulfonated polyethylene for blending modification, the material composition and ratio are optimized, effectively solving the incompatibility problem between nitrile rubber and EPDM rubber, improving the compatibility of the blend, thereby enhancing the material's strength and wear resistance. Furthermore, it exhibits excellent ozone resistance, weather resistance, and low-temperature elasticity, ensuring that rail transit damping components can effectively resist aging cracking and low-temperature embrittlement during long-term service in harsh outdoor environments, maintaining stable performance and significantly extending service life. This material provides durable, reliable, and efficient damping capabilities for high-speed rail vehicles, ensuring driving safety and comfort, and is particularly suitable for critical components subjected to high-frequency, high-load impacts.

[0045] The multi-component composite elastomer material provided by this invention has a total content of EPDM rubber and modified EPDM rubber of approximately 20-35%. This maximizes the utilization of EPDM rubber's excellent ozone resistance, weather resistance, and low-temperature elasticity, while also addressing the problem that an excessively high proportion of EPDM rubber would severely weaken the inherent oil resistance of nitrile rubber in the blend by controlling its content within an appropriate range. The addition of polyethylene enhances the material's rigidity and tensile strength.

[0046] By employing a composite accelerator, a complete vulcanization speed system ranging from "high-speed" and "high-speed" to "medium-speed" and "after-effect" is constructed. Combined with sulfur vulcanizing agent and zinc oxide activator, it promotes the crosslinking of nitrile rubber and EPDM rubber and constructs a dense three-dimensional network structure, improving the mechanical properties and elasticity of the material. It also endows the material with excellent heat resistance, aging resistance and compression set resistance, making it suitable for extreme working conditions.

[0047] Introducing approximately 10-15% of modified multi-walled carbon nanotubes and 20-30% of carbon black (N330) into the blend as reinforcing fillers, utilizing their high specific surface area and strong interfacial interaction, in conjunction with the silane coupling agent Si-69 (0.9-1.7%), achieves uniform dispersion and strong interfacial bonding of nanoparticles in the rubber matrix, significantly improving the tensile strength, tear strength, and abrasion resistance of the material.

[0048] The multi-component composite elastomer material provided by this invention combines the oil resistance of nitrile rubber, the weather resistance / ozone resistance / low temperature resistance of EPDM rubber, and the ultra-high wear resistance and mechanical strength of nano-reinforcement, while maintaining excellent elasticity and dynamic fatigue performance, meeting the requirements of long service life, high reliability and safety and comfort of rail transit buffer and vibration damping components under harsh environments and high-frequency loads.

[0049] The multi-component composite elastomer material provided by this invention achieves multiple advantages of "oil resistance, weather resistance, high strength, easy processing, and low cost" through the composite of nitrile rubber, ethylene propylene diene monomer (EPDM), modified EPDM, maleic anhydride-grafted chlorosulfonated polyethylene, and polypropylene. Elastic buffer pads made from this multi-component composite elastomer material exhibit excellent comprehensive mechanical properties and outstanding cushioning and vibration reduction capabilities. This multi-component composite elastomer combines the toughness of nitrile rubber, the high elasticity of EPDM, and the rigidity of polypropylene, enabling the buffer pad to possess both high tensile strength and good elasticity. The addition of modified EPDM and maleic anhydride-grafted chlorosulfonated polyethylene enhances the material's tear resistance, and combined with the wear-resistant properties of nitrile rubber, the pad maintains its structural integrity under high-frequency vibration or friction conditions. This rubber-plastic material combines oil resistance and weather resistance, enabling it to adapt to complex environments. The polar molecular structure of nitrile rubber gives the material excellent resistance to mineral oil and hydraulic oil. The composite of EPDM rubber and modified EPDM rubber enhances the material's resistance to ozone, ultraviolet radiation, and high and low temperatures.

[0050] Please refer to Figure 1 As shown, the multi-component composite elastomer material provided by this invention can be used as an elastic buffer pad in the steel spring damping support of the track system (track floating plate), and can also be used as a pad under the iron pad plate and the rail pad plate in the railway system. It has high stability, high insulation and high weather resistance.

[0051] More specifically, the preparation of the modified EPDM rubber includes:

[0052] EPDM rubber is heated to 140~170℃, and zinc methacrylate, glycidyl methacrylate and allyl (3-isocyanate-4-tolyl) carbamate are added sequentially to carry out a melt reaction. The modified EPDM rubber is obtained by extrusion.

[0053] The modified EPDM rubber comprises the following raw materials in parts by weight: 15-20 parts of EPDM rubber, 0.2-1 parts of zinc methacrylate, 1-2 parts of glycidyl methacrylate, and 1-2 parts of allyl (3-isocyanate-4-tolyl) carbamate.

[0054] In the modified EPDM rubber provided by this invention, modification of EPDM rubber with zinc methacrylate, glycidyl methacrylate, and allyl (3-isocyanate-4-tolyl) urethane significantly improves the compatibility between EPDM rubber and nitrile rubber, facilitates co-vulcanization at the interface of the two phases, increases the density of the two phases during blending, promotes the formation of a stable interpenetrating network structure in the rubber matrix, and enhances the stability of rubber properties. Zinc methacrylate can both polymerize with the blend and undergo self-polymerization, and its molecular structure contains ionic bonds formed by zinc cations and carboxylate anions, which helps to form a crosslinked network structure in the blend, increasing the crosslink density and thus improving the hardness, tensile strength, and tear strength of the blend. Glycidyl methacrylate and allyl (3-isocyanate-4-tolyl) urethane have a compatibilizing effect, reducing the number of molecular chain entanglement points between the EPDM rubber phase and the nitrile rubber phase, enhancing the slippage of macromolecular chain segments in the rubber matrix, and thus achieving a plasticizing effect.

[0055] In the modified EPDM rubber provided by this invention, the modification of EPDM rubber can also reduce the proportion of EPDM rubber. The total content of EPDM rubber and modified EPDM rubber is about 20-35%. This can maximize the utilization of the excellent ozone resistance, weather resistance and low temperature elasticity of EPDM rubber, and also solve the problem that an excessively high proportion of EPDM rubber will seriously weaken the inherent oil resistance of nitrile rubber in the blend by controlling its content within a suitable range, thereby improving the oil resistance of the rubber material.

[0056] More specifically, the preparation of the maleic anhydride-grafted chlorosulfonated polyethylene includes:

[0057] After mixing chlorosulfonated polyethylene and maleic anhydride evenly, dicumyl peroxide is added and stirring is continued for 5-10 minutes to obtain the maleic anhydride-grafted chlorosulfonated polyethylene.

[0058] The maleic anhydride-grafted chlorosulfonated polyethylene comprises the following raw materials in parts by weight: 20-30 parts of chlorosulfonated polyethylene, 10-20 parts of maleic anhydride, and 0.1-0.5 parts of dicumyl peroxide;

[0059] The grafting rate of the maleic anhydride-grafted chlorosulfonated polyethylene is 2-2.5%.

[0060] In the maleic anhydride-grafted chlorosulfonated polyethylene provided by this invention, the main chain of the chlorosulfonated polyethylene is a chemically stable saturated hydrocarbon, similar in structure to the main chain of ethylene propylene diene monomer (EPDM) rubber, enabling entanglement. The side groups are polar chlorine atoms, with polarity close to that of nitrile rubber, resulting in good compatibility with nitrile rubber. To further improve the compatibility of chlorosulfonated polyethylene, both polar aldehyde groups and non-polar olefin segments are grafted using maleic anhydride. This increases the compatibility of chlorosulfonated polyethylene with nitrile rubber and EPDM rubber blends while also promoting the formation of a co-crosslinking network in the blended rubber, thereby improving the strength and wear resistance of the material.

[0061] Furthermore, the chlorosulfonated polyethylene provided by this invention also possesses highly active chlorosulfonyl groups that can provide crosslinking sites for the vulcanization of chlorosulfonated polyethylene. The accelerator dithiopyrophosphate releases sulfur during the vulcanization process, which is then used for the vulcanization of chlorosulfonated polyethylene. In this invention, the accelerator dithiopyrophosphate acts as both an accelerator and a vulcanizing agent for chlorosulfonated polyethylene, bonding nitrile rubber and EPDM rubber together. This improves the asynchronous vulcanization of nitrile rubber and EPDM rubber, promotes the formation of a co-crosslinked network in the nitrile rubber and EPDM rubber blend, thereby improving the strength and wear resistance of the material.

[0062] More specifically, the preparation of the modified multi-walled carbon nanotubes includes:

[0063] Gallic acid was dissolved in Tris hydrochloric acid buffer at pH 8-9. Multi-walled carbon nanotubes were added at a mass ratio of gallic acid to multi-walled carbon nanotubes of 1:(3-5). The mixture was ultrasonically dispersed at 40-50℃ for 5-7 hours, and then stirred at room temperature for 2-4 hours. After filtration and washing, the modified multi-walled carbon nanotubes were obtained.

[0064] Multi-walled carbon nanotubes (MWCNTs) possess unique properties due to their extremely high aspect ratio and rigid chemical structure composed of a carbon network. MWCNTs can be embedded in the two-phase structure of blended rubbers. Their large aspect ratio forces the two-phase structure of the blended rubber to "stitch together," enhancing the interaction between the two phases, reducing the interfacial tension in the contact area of ​​incompatible components, and improving the compatibility of the two phases, thus acting as a compatibilizer. However, MWCNTs are prone to entanglement and aggregation, resulting in poor dispersibility. Chemical modification of MWCNTs with gallic acid can enhance the interfacial bonding between MWCNTs and the rubber matrix, while optimizing the dispersibility of MWCNTs within the rubber matrix, thereby improving the overall mechanical properties of the rubber material. Gallic acid molecules are anchored to the graphene structure of MWCNTs through π-π interactions via aromatic rings, thus adsorbing onto their surface. Furthermore, the ortho-polyphenolic group of gallic acid can be oxidized to an ortho-quinone group, which undergoes a Michael addition reaction with polysulfide free radicals during the rubber vulcanization process. Therefore, gallic acid molecules adsorbed on the surface of multi-walled carbon nanotubes can establish a strong interface between the rubber matrix and the multi-walled carbon nanotubes through covalent and non-covalent interactions, thereby improving the overall compatibility of the rubber.

[0065] Further specified, the multi-component composite elastomer material satisfies at least one of the following:

[0066] The oxidant is zinc oxide; the activator is stearic acid; and the coupling agent is Si-69.

[0067] More specifically, in the multi-component composite elastomer material for the track floating plate, the antioxidant is a composition containing 0.2 to 0.4 parts by weight of 2,2,4-trimethyl-1,2-dihydroquinoline polymer and 0.3 to 0.7 parts by weight of N-cyclohexyl-N'-phenyl-p-phenylenediamine.

[0068] More specifically, the accelerator is a composition containing 0.4 to 0.8 parts by weight of zinc dibutyldithiocarbamate, 0.2 to 0.5 parts by weight of accelerator dithiopyrophosphate, 0.2 to 0.6 parts by weight of dibenzothiazole disulfide, and 0.15 to 0.35 parts by weight of N-cyclohexyl-2-benzothiazole sulfenamide.

[0069] In blends of nitrile butadiene rubber (NBR) and ethylene propylene diene monomer (EPDM), NBR exhibits high vulcanization activity and a fast vulcanization rate, while EPDM has low vulcanization activity and a slow vulcanization rate. Using a single accelerator system can easily lead to over-vulcanization of the NBR phase and under-vulcanization of the EPDM phase, resulting in poor interfacial bonding and a decline in overall performance.

[0070] Therefore, the accelerator provided by this invention is a composition containing four accelerators. Zinc dibutyldithiocarbamate (BZ) acts as an ultra-fast co-catalyst with extremely high activity, significantly increasing the vulcanization start-up speed, especially effectively driving the slower vulcanization rate of the EPDM rubber phase, enabling it to start up faster and keep pace with the nitrile rubber phase. Dithiopyrophosphate (DTPP), as a sulfur donor and multifunctional accelerator, not only provides active sulfur but also promotes co-vulcanization. The decomposition and release of uniformly distributed active sulfur is more easily captured by rubber molecules, helping to form a more uniform co-crosslink at the interface between the nitrile rubber and EPDM rubber phases, thus better matching the vulcanization rates of the two rubbers, improving the bonding strength between the rubber phases, and thereby improving the co-vulcanization between the blended rubber phases. Dibenzothiazole disulfide (DM) acts as a medium-speed main accelerator, optimizing the vulcanization rate and making the vulcanization curve more stable. It also synergistically stabilizes the problem of excessively rapid vulcanization caused by the addition of zinc dibutyldithiocarbamate and N-cyclohexyl-2-benzothiazole sulfenamide, thus balancing the vulcanization rate and stabilizing the vulcanization process.

[0071] This composite accelerator constructs a complete vulcanization speed system ranging from "high-speed" and "medium-speed" to "after-effect." This combination avoids the problems of excessively slow, excessively fast, or narrow plateau vulcanization speeds that may occur with single accelerators. This composite accelerator ensures that at the vulcanization temperature, nitrile rubber and ethylene propylene diene monomer (EPDM) rubber can begin crosslinking at similar speeds and form a dense network, firmly bonded at the phase interface through chemical bonds, thus achieving true "co-vulcanization."

[0072] Furthermore, the accelerator zinc dithiocarbamate (BZ) has a good promoting effect on the sulfonyl chloride crosslinking of CSM. The accelerator dithiopyrophosphate (DPTT) not only acts as an accelerator to increase the vulcanization speed during the vulcanization process, but also acts as a vulcanizing agent to release sulfur, thereby achieving crosslinking of CSM, improving the mismatch in vulcanization speed between nitrile rubber and EPDM, increasing the degree of crosslinking in the blend, constructing a strong co-crosslinked network, and improving the strength and wear resistance of the material.

[0073] In this invention, the accelerator dithiophosphate acts as both an accelerator and a vulcanizing agent for chlorosulfonated polyethylene, bonding nitrile rubber and ethylene propylene diene monomer (EPDM) rubber together. This improves the asynchronous vulcanization of nitrile rubber and EPDM rubber, promotes the formation of a co-crosslinked network in the blended nitrile rubber and EPDM rubber, thereby improving the strength and abrasion resistance of the blended rubber.

[0074] More specifically, the vulcanizing agent is sulfur.

[0075] A method for preparing a multi-component composite elastomer material for track floating plates, as described above, comprising the following steps:

[0076] Nitrile rubber, ethylene propylene diene monomer (EPDM) rubber and polypropylene are mixed and left to stand for at least 8 hours. Then, modified EPDM rubber and maleic anhydride-grafted chlorosulfonated polyethylene are added and mixed again to obtain a multi-component composite elastomer plasticized rubber.

[0077] Carbon black, modified multi-walled carbon nanotubes, hollow fibers, paraffin oil, oxidant, activator, antioxidant, coupling agent, accelerator and vulcanizing agent are added to the multi-component composite elastomer plasticized rubber, and after mixing and pressing, a semi-finished rubber raw material is obtained.

[0078] The semi-finished rubber raw material is vulcanized by compression molding to obtain the multi-component composite elastomer material.

[0079] More specifically, the vulcanization treatment employs a phased, gradual cooling process:

[0080] In the first vulcanization stage, the vulcanization temperature is 130–160℃, the time is 100–600s, and the vulcanization pressure is 5–12MPa.

[0081] The second vulcanization stage involves a vulcanization temperature of 120–150℃, a time of 100–600s, and a vulcanization pressure of 5–12MPa.

[0082] The third vulcanization stage involves a vulcanization temperature of 110–140℃, a vulcanization time of 100–600s, and a vulcanization pressure of 5–12MPa.

[0083] In the preparation method of the multi-component composite elastomer material for track floating plates provided by this invention, the vulcanization treatment adopts a staged gradual cooling method. The vulcanization temperature in the first stage is 130-160℃, rapidly heating the molded semi-finished rubber to make the internal and external temperatures of the semi-finished rubber tend to be uniform and to begin cross-linking, initially establishing a three-dimensional network framework. The second and third vulcanization stages gradually reduce the temperature, allowing the cross-linking reaction to be completed at a relatively mild temperature, preventing the outer layer of the semi-finished rubber from over-sulfurization degradation caused by prolonged high temperatures. This staged gradual cooling vulcanization treatment method ensures that the overall cross-linking density distribution of the final multi-component composite elastomer material is more uniform, avoiding problems such as differences in internal and external hardness, internal bubbles, or tearing starting from the inside during use caused by uneven vulcanization.

[0084] To further illustrate the present invention, the following description, in conjunction with embodiments, illustrates a multi-component composite elastomer material for track floating slabs and its preparation method. However, it should be understood that these embodiments are implemented under the premise of the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. They are only for further illustrating the features and advantages of the present invention, and are not intended to limit the scope of the claims of the present invention. The protection scope of the present invention is not limited to the following embodiments.

[0085] Example 1:

[0086] The multi-component composite elastomer material for track floating slabs provided in this embodiment includes the following raw materials in parts by weight: 25 parts nitrile rubber, 15 parts ethylene propylene diene monomer (EPDM) rubber, 5 parts modified EPDM rubber, 10 parts maleic anhydride-grafted chlorosulfonated polyethylene, 15 parts polypropylene, 20 parts carbon black, 10 parts modified multi-walled carbon nanotubes, 2 parts hollow fiber, 10 parts paraffin oil, 0.8 parts zinc oxide, 0.7 parts stearic acid, 0.5 parts antioxidant, 0.9 parts Si-69, 0.95 parts accelerator, and 0.2 parts sulfur.

[0087] The preparation of modified EPDM rubber includes: heating EPDM rubber to 140°C, sequentially adding zinc methacrylate, glycidyl methacrylate and allyl (3-isocyanate-4-tolyl) carbamate for melt reaction, and extruding to obtain the modified EPDM rubber; wherein the modified EPDM rubber comprises the following raw materials in parts by weight: 15 parts EPDM rubber, 0.2 parts zinc methacrylate, 1 part glycidyl methacrylate and 1 part allyl (3-isocyanate-4-tolyl) carbamate.

[0088] The preparation of maleic anhydride-grafted chlorosulfonated polyethylene includes: mixing chlorosulfonated polyethylene and maleic anhydride evenly, adding dicumyl peroxide and stirring for 5 minutes to obtain the maleic anhydride-grafted chlorosulfonated polyethylene; wherein the maleic anhydride-grafted chlorosulfonated polyethylene comprises the following raw materials in parts by weight: 20 parts of chlorosulfonated polyethylene, 10 parts of maleic anhydride and 0.1 parts of dicumyl peroxide; the grafting rate of the maleic anhydride-grafted chlorosulfonated polyethylene is 2%.

[0089] The preparation of the modified multi-walled carbon nanotubes includes: dissolving gallic acid in Tris hydrochloric acid buffer at pH=8, adding multi-walled carbon nanotubes at a mass ratio of gallic acid to multi-walled carbon nanotubes of 1:3, mixing, ultrasonically dispersing at 40°C for 5 hours, stirring at room temperature for 2 hours, and obtaining the modified multi-walled carbon nanotubes after filtration and washing.

[0090] The antioxidant is a composition containing 0.2 parts by weight of 2,2,4-trimethyl-1,2-dihydroquinoline polymer and 0.3 parts by weight of N-cyclohexyl-N'-phenyl-p-phenylenediamine.

[0091] The accelerator is a composition containing 0.4 parts by weight of zinc dibutyldithiocarbamate, 0.2 parts by weight of accelerator dithiopyrophosphate, 0.2 parts by weight of dibenzothiazole disulfide, and 0.15 parts by weight of N-cyclohexyl-2-benzothiazole sulfenamide.

[0092] The method for preparing a multi-component composite elastomer material for a track floating plate provided in this embodiment includes the following steps:

[0093] Nitrile rubber, ethylene propylene diene monomer (EPDM) rubber and polypropylene are mixed and left to stand for 8 hours. Then, modified EPDM rubber and maleic anhydride-grafted chlorosulfonated polyethylene are added and the mixture is further mixed to obtain a multi-component composite elastomer plasticized rubber.

[0094] Carbon black, modified multi-walled carbon nanotubes, hollow fibers, paraffin oil, oxidant, activator, antioxidant, coupling agent, accelerator and vulcanizing agent are added to the multi-component composite elastomer plasticized rubber, and after mixing and pressing, a semi-finished rubber raw material is obtained.

[0095] The semi-finished rubber raw material is vulcanized by compression molding to obtain the multi-component composite elastomer material.

[0096] The vulcanization process employs a phased, gradual cooling process, including: a first vulcanization stage with a vulcanization temperature of 160°C, a time of 100 seconds, and a vulcanization pressure of 5 MPa; a second vulcanization stage with a vulcanization temperature of 150°C, a time of 100 seconds, and a vulcanization pressure of 5 MPa; and a third vulcanization stage with a vulcanization temperature of 140°C, a time of 100 seconds, and a vulcanization pressure of 5 MPa.

[0097] Example 2:

[0098] The multi-component composite elastomer material for track floating slabs provided in this embodiment includes the following raw materials in parts by weight: 30 parts nitrile rubber, 22 parts ethylene propylene diene monomer (EPDM) rubber, 7 parts modified EPDM rubber, 12 parts maleic anhydride-grafted chlorosulfonated polyethylene, 20 parts polypropylene, 25 parts carbon black, 14 parts modified multi-walled carbon nanotubes, 3 parts hollow fiber, 12 parts paraffin oil, 1.2 parts zinc oxide, 0.9 parts stearic acid, 0.8 parts antioxidant, 1.4 parts Si-69, 1.48 parts accelerator, and 0.35 parts sulfur.

[0099] The preparation of the modified EPDM rubber includes: heating EPDM rubber to 155°C, sequentially adding zinc methacrylate, glycidyl methacrylate and allyl (3-isocyanate-4-tolyl) carbamate for melt reaction, and extruding to obtain the modified EPDM rubber; wherein the modified EPDM rubber comprises the following raw materials in parts by weight: 18 parts EPDM rubber, 0.6 parts zinc methacrylate, 1.4 parts glycidyl methacrylate and 1.6 parts allyl (3-isocyanate-4-tolyl) carbamate.

[0100] The preparation of maleic anhydride-grafted chlorosulfonated polyethylene includes: mixing chlorosulfonated polyethylene and maleic anhydride evenly, adding dicumyl peroxide and stirring for 8 minutes to obtain the maleic anhydride-grafted chlorosulfonated polyethylene; wherein the maleic anhydride-grafted chlorosulfonated polyethylene comprises the following raw materials in parts by weight: 24 parts of chlorosulfonated polyethylene, 16 parts of maleic anhydride and 0.3 parts of dicumyl peroxide; the grafting rate of the maleic anhydride-grafted chlorosulfonated polyethylene is 2.3%.

[0101] The preparation of the modified multi-walled carbon nanotubes includes: dissolving gallic acid in Tris hydrochloric acid buffer at pH 8.5, adding multi-walled carbon nanotubes at a mass ratio of gallic acid to multi-walled carbon nanotubes of 1:4.2, ultrasonically dispersing at 46°C for 6 hours, stirring at room temperature for 3.5 hours, and obtaining the modified multi-walled carbon nanotubes after filtration and washing.

[0102] The antioxidant is a composition containing 0.32 parts by weight of 2,2,4-trimethyl-1,2-dihydroquinoline polymer and 0.55 parts by weight of N-cyclohexyl-N'-phenyl-p-phenylenediamine.

[0103] The accelerator is a composition containing 0.55 parts by weight of zinc dibutyldithiocarbamate, 0.35 parts by weight of accelerator dithiopyrophosphate, 0.4 parts by weight of dibenzothiazole disulfide, and 0.25 parts by weight of N-cyclohexyl-2-benzothiazole sulfenamide.

[0104] The method for preparing a multi-component composite elastomer material for a track floating plate provided in this embodiment includes the following steps:

[0105] Nitrile rubber, ethylene propylene diene monomer (EPDM) rubber and polypropylene are mixed and left to stand for 10 hours. Then, modified EPDM rubber and maleic anhydride-grafted chlorosulfonated polyethylene are added and mixed again to obtain a multi-component composite elastomer plasticized rubber.

[0106] Carbon black, modified multi-walled carbon nanotubes, hollow fibers, paraffin oil, oxidant, activator, antioxidant, coupling agent, accelerator and vulcanizing agent are added to the multi-component composite elastomer plasticized rubber, and after mixing and pressing, a semi-finished rubber raw material is obtained.

[0107] The semi-finished rubber raw material is vulcanized by compression molding to obtain the multi-component composite elastomer material.

[0108] The vulcanization process employs a phased, gradual cooling process, including: a first vulcanization stage with a vulcanization temperature of 140°C, a time of 300s, and a vulcanization pressure of 8MPa; a second vulcanization stage with a vulcanization temperature of 130°C, a time of 300s, and a vulcanization pressure of 8MPa; and a third vulcanization stage with a vulcanization temperature of 120°C, a time of 300s, and a vulcanization pressure of 8MPa.

[0109] Example 3:

[0110] The multi-component composite elastomer material for track floating slabs provided in this embodiment includes the following raw materials in parts by weight: 40 parts nitrile rubber, 25 parts ethylene propylene diene monomer (EPDM) rubber, 10 parts modified EPDM rubber, 15 parts maleic anhydride-grafted chlorosulfonated polyethylene, 25 parts polypropylene, 30 parts carbon black, 15 parts modified multi-walled carbon nanotubes, 5 parts hollow fiber, 15 parts paraffin oil, 1.6 parts zinc oxide, 1.2 parts stearic acid, 1.1 parts antioxidant, 1.7 parts Si-69, 2.25 parts accelerator, and 0.6 parts sulfur.

[0111] The preparation of the modified EPDM rubber includes: heating EPDM rubber to 170°C, sequentially adding zinc methacrylate, glycidyl methacrylate and allyl (3-isocyanate-4-tolyl) carbamate for melt reaction, and extruding to obtain the modified EPDM rubber; wherein the modified EPDM rubber comprises the following raw materials in parts by weight: 20 parts EPDM rubber, 1 part zinc methacrylate, 2 parts glycidyl methacrylate and 2 parts allyl (3-isocyanate-4-tolyl) carbamate.

[0112] The preparation of maleic anhydride-grafted chlorosulfonated polyethylene includes: mixing chlorosulfonated polyethylene and maleic anhydride evenly, adding dicumyl peroxide and stirring for 10 minutes to obtain the maleic anhydride-grafted chlorosulfonated polyethylene; wherein the maleic anhydride-grafted chlorosulfonated polyethylene comprises the following raw materials in parts by weight: 30 parts of chlorosulfonated polyethylene, 20 parts of maleic anhydride and 0.5 parts of dicumyl peroxide; the grafting rate of the maleic anhydride-grafted chlorosulfonated polyethylene is 2.5%.

[0113] The preparation of the modified multi-walled carbon nanotubes includes: dissolving gallic acid in Tris hydrochloric acid buffer at pH=9, adding multi-walled carbon nanotubes at a mass ratio of gallic acid to multi-walled carbon nanotubes of 1:5, mixing, ultrasonically dispersing at 50°C for 7 hours, stirring at room temperature for 4 hours, and obtaining the modified multi-walled carbon nanotubes after filtration and washing.

[0114] The antioxidant is a composition containing 0.4 parts by weight of 2,2,4-trimethyl-1,2-dihydroquinoline polymer and 0.3-0.7 parts by weight of N-cyclohexyl-N'-phenyl-p-phenylenediamine.

[0115] The accelerator is a composition containing 0.8 parts by weight of zinc dibutyldithiocarbamate, 0.5 parts by weight of accelerator dithiopyrophosphate, 0.6 parts by weight of dibenzothiazole disulfide, and 0.35 parts by weight of N-cyclohexyl-2-benzothiazole sulfenamide.

[0116] The method for preparing a multi-component composite elastomer material for a track floating plate provided in this embodiment includes the following steps:

[0117] Nitrile rubber, ethylene propylene diene monomer (EPDM) rubber and polypropylene are mixed and left to stand for 8 hours. Then, modified EPDM rubber and maleic anhydride-grafted chlorosulfonated polyethylene are added and the mixture is further mixed to obtain a multi-component composite elastomer plasticized rubber.

[0118] Carbon black, modified multi-walled carbon nanotubes, hollow fibers, paraffin oil, oxidant, activator, antioxidant, coupling agent, accelerator and vulcanizing agent are added to the multi-component composite elastomer plasticized rubber, and after mixing and pressing, a semi-finished rubber raw material is obtained.

[0119] The semi-finished rubber raw material is vulcanized by compression molding to obtain the multi-component composite elastomer material.

[0120] The vulcanization process employs a phased, gradual cooling process, comprising: a first vulcanization stage with a vulcanization temperature of 130°C, a time of 600s, and a vulcanization pressure of 12MPa; a second vulcanization stage with a vulcanization temperature of 120°C, a time of 600s, and a vulcanization pressure of 12MPa; and a third vulcanization stage with a vulcanization temperature of 110°C, a time of 600s, and a vulcanization pressure of 12MPa.

[0121] The performance of the multi-component composite elastomer materials prepared in Examples 1-3 was tested. (1) Shore A hardness was tested according to GB / T 531.1-2008; (2) Working resistance was tested according to GB / T 1410-2006; (3) Tensile properties were tested according to GB / T528, using the tensile mode and the I-type condition; (4) Tensile strength after hot air aging was tested according to GB / T3512, with aging conditions of 100℃ and 72h; (5) Tensile strength was tested according to GB / T528; (6) Tensile strength after hot air aging was tested according to GB / T3512, with aging conditions of 100℃ and 72h; (7) 200% elongation was tested according to GB / T528; (8) Akron abrasion was tested according to GB / T1689; (9) Oil resistance was tested according to GB / T The following tests were conducted: (10) Alkali resistance was tested according to GB / T1690-2010; (11) Brittleness temperature was tested according to GB / T1682; (12) Ozone aging resistance was tested according to GB / T7762-2014; (13) Fatigue test was conducted according to TB / T1495; (14) Static stiffness was tested according to Appendix A of TB / T3395.1. The test results are shown in Table 1 below:

[0122] Table 1 Performance test results of the multi-component composite elastomer materials prepared in Examples 1-3

[0123] Testing items National Railway Technical Specifications Example 1 Example 2 Example 3 Hardness (Shore A) ≥65 85 87 88 Operating resistance / Ω <![CDATA[≥1×10 6 ]]> <![CDATA[1.1×10 9 ]]> <![CDATA[1.3×10 9 ]]> <![CDATA[1.4×10 9 ]]> Tensile strength / MPa ≥12.5 24.3 26.0 26.4 Tensile strength (after hot air aging) / MPa ≥10 19.8 20.7 21.1 Elongation at break / % ≥250 305 314 323 Elongation at break (after hot air aging) / % ≥180 268 272 280 200% constant tensile stress / MPa ≥9.5 11.2 11.4 11.7 <![CDATA[Akkron Abrasion / cm 3 / 1.61Km]]> ≤0.6 0.23 0.17 0.15 Oil resistance (percentage of change in mass) / % ≤20 12.2 13.5 14.3 Alkali resistance (saturated alkali, volume change rate at 23℃ for 24 hours) / % ≤0.6 0.45 0.48 0.54 Brittleness temperature / °C -20 -48 -57 -59 Ozone aging resistance No cracks No cracks No cracks No cracks Rate of change in static stiffness after 3 million fatigue cycles / % ≤25 11.6 11.2 10.9 Static stiffness / KN / mm ≥500 750 780 795

[0124] As can be seen from the results in Table 1, the multi-component composite elastomer material provided by the embodiments of the present invention exhibits excellent overall performance, providing durable, reliable and efficient buffering and vibration reduction capabilities for high-speed rail transit vehicles, ensuring driving safety and comfort.

[0125] Compare with Example 1:

[0126] The multi-component composite elastomer material and its preparation method for track floating slabs provided in this comparative example are the same as those in Example 1, except that modified EPDM rubber is not added to the multi-component composite elastomer material in this comparative example.

[0127] Compare with Example 2:

[0128] The multi-component composite elastomer material and its preparation method for track floating slabs provided in this comparative example are the same as those in Example 1, except that maleic anhydride-grafted chlorosulfonated polyethylene is not added to the multi-component composite elastomer material in this comparative example.

[0129] Compare with Example 3:

[0130] The multi-component composite elastomer material and its preparation method for track floating plates provided in this comparative example are the same as those in Example 1, except that the multi-walled carbon nanotubes added to the multi-component composite elastomer material in this comparative example are not modified with gallic acid.

[0131] The performance of the multi-component composite elastomer materials prepared in Comparative Examples 1-3 was tested, and the test results are shown in Table 2.

[0132] Table 2 Performance test results of the multi-component composite elastomer materials prepared in Comparative Examples 1-3

[0133] Testing items National Railway Technical Specifications Compare with Example 1 Compare with Example 2 Compare with Example 3 Hardness (Shore A) ≥65 75.5 76.7 79.2 Operating resistance / Ω <![CDATA[≥1×10 6 ]]> <![CDATA[0.7×10 9 ]]> <![CDATA[0.78×10 9 ]]> <![CDATA[0.9×10 9 ]]> Tensile strength / MPa ≥12.5 17.1 17.5 18.3 Tensile strength (after hot air aging) / MPa ≥10 12.3 12.9 13.7 Elongation at break / % ≥250 255 268 282 Elongation at break (after hot air aging) / % ≥180 192 203 207 200% constant tensile stress / MPa ≥9.5 12.7 12.8 12.4 <![CDATA[Akkron Abrasion / cm 3 / 1.61Km]]> ≤0.6 0.42 0.38 0.31 Oil resistance (percentage of change in mass) / % ≤20 8.3 8.6 9.7 Alkali resistance (saturated alkali, volume change rate at 23℃ for 24 hours) / % ≤0.6 0.22 0.25 0.33 Brittleness temperature / °C -20 -39 -40 -44 Ozone aging resistance No cracks No cracks No cracks No cracks Rate of change in static stiffness after 3 million fatigue cycles / % ≤25 18.2 17.5 15.2 Static stiffness / KN / mm ≥500 635 652 688

[0134] As can be seen from the results in Table 2, the addition of multi-walled carbon nanotubes in Comparative Example 3, without modification by gallic acid, had a certain impact on the overall performance of the material. However, the absence of modified EPDM rubber in Comparative Example 1 and the absence of maleic anhydride-grafted chlorosulfonated polyethylene in Comparative Example 3 had a greater impact on the overall performance of the material compared to Comparative Example 3. A comparative analysis of the examples and the comparative examples shows that only the multi-component composite elastomer material provided by this invention exhibits excellent overall performance.

[0135] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-component composite elastomer material for use in track floating slabs, characterized in that, The raw materials include the following parts by weight: 25-40 parts of nitrile rubber, 15-25 parts of ethylene propylene diene monomer (EPDM) rubber, 5-10 parts of modified EPDM rubber, 10-15 parts of maleic anhydride-grafted chlorosulfonated polyethylene, 15-25 parts of polypropylene, 20-30 parts of carbon black, 10-15 parts of modified multi-walled carbon nanotubes, 2-5 parts of hollow fiber, 10-15 parts of paraffin oil, 0.8-1.6 parts of oxidant, 0.7-1.2 parts of activator, 0.5-1.1 parts of antioxidant, 0.9-1.7 parts of coupling agent, 0.95-2.25 parts of accelerator, and 0.2-0.6 parts of vulcanizing agent.

2. The multi-component composite elastomer material for track floating slabs according to claim 1, characterized in that, The preparation of the modified EPDM rubber includes: EPDM rubber is heated to 140~170℃, and zinc methacrylate, glycidyl methacrylate and allyl (3-isocyanate-4-tolyl) carbamate are added sequentially to carry out a melt reaction. The modified EPDM rubber is obtained by extrusion. The modified EPDM rubber comprises the following raw materials in parts by weight: 15-20 parts of EPDM rubber, 0.2-1 parts of zinc methacrylate, 1-2 parts of glycidyl methacrylate, and 1-2 parts of allyl (3-isocyanate-4-tolyl) carbamate.

3. The multi-component composite elastomer material for track floating slabs according to claim 1, characterized in that, The preparation of the maleic anhydride-grafted chlorosulfonated polyethylene includes: After mixing chlorosulfonated polyethylene and maleic anhydride evenly, dicumyl peroxide is added and stirring is continued for 5-10 minutes to obtain the maleic anhydride-grafted chlorosulfonated polyethylene. The maleic anhydride-grafted chlorosulfonated polyethylene comprises the following raw materials in parts by weight: 20-30 parts of chlorosulfonated polyethylene, 10-20 parts of maleic anhydride, and 0.1-0.5 parts of dicumyl peroxide; The grafting rate of the maleic anhydride-grafted chlorosulfonated polyethylene is 2-2.5%.

4. The multi-component composite elastomer material for track floating slabs according to claim 1, characterized in that, The preparation of the modified multi-walled carbon nanotubes includes: Gallic acid was dissolved in Tris hydrochloric acid buffer at pH 8-9. Multi-walled carbon nanotubes were added at a mass ratio of gallic acid to multi-walled carbon nanotubes of 1:(3-5). The mixture was ultrasonically dispersed at 40-50℃ for 5-7 hours, and then stirred at room temperature for 2-4 hours. After filtration and washing, the modified multi-walled carbon nanotubes were obtained.

5. The multi-component composite elastomer material for track floating slabs according to claim 1, characterized in that, The multi-component composite elastomer material satisfies at least one of the following: The oxidant is zinc oxide; the activator is stearic acid; and the coupling agent is Si-69.

6. The multi-component composite elastomer material for track floating slabs according to claim 1, characterized in that, The antioxidant is a composition containing 0.2 to 0.4 parts by weight of 2,2,4-trimethyl-1,2-dihydroquinoline polymer and 0.3 to 0.7 parts by weight of N-cyclohexyl-N'-phenyl-p-phenylenediamine.

7. The multi-component composite elastomer material for track floating slabs according to claim 1, characterized in that, The accelerator is a composition containing 0.4 to 0.8 parts by weight of zinc dibutyldithiocarbamate, 0.2 to 0.5 parts by weight of accelerator dithiopyrophosphate, 0.2 to 0.6 parts by weight of dibenzothiazole disulfide, and 0.15 to 0.35 parts by weight of N-cyclohexyl-2-benzothiazole sulfenamide.

8. The multi-component composite elastomer material for track floating slabs according to claim 1, characterized in that, The vulcanizing agent is sulfur.

9. A method for preparing a multi-component composite elastomer material for track floating slabs, characterized in that, The preparation method uses the multi-component composite elastomer material for track floating plates as described in any one of claims 1-8, and the preparation method includes the following steps: Nitrile rubber, ethylene propylene diene monomer (EPDM) rubber and polypropylene are mixed and left to stand for at least 8 hours. Then, modified EPDM rubber and maleic anhydride-grafted chlorosulfonated polyethylene are added and mixed again to obtain a multi-component composite elastomer plasticized rubber. Carbon black, modified multi-walled carbon nanotubes, hollow fibers, paraffin oil, oxidant, activator, antioxidant, coupling agent, accelerator and vulcanizing agent are added to the multi-component composite elastomer plasticized rubber, and after mixing and pressing, a semi-finished rubber raw material is obtained. The semi-finished rubber raw material is vulcanized by compression molding to obtain the multi-component composite elastomer material.

10. The method for preparing the multi-component composite elastomer material for track floating plates according to claim 9, characterized in that, The vulcanization process employs a phased, gradual cooling process, including: In the first vulcanization stage, the vulcanization temperature is 130–160℃, the time is 100–600s, and the vulcanization pressure is 5–12MPa. The second vulcanization stage involves a vulcanization temperature of 120–150℃, a time of 100–600s, and a vulcanization pressure of 5–12MPa. The third vulcanization stage involves a vulcanization temperature of 110–140℃, a vulcanization time of 100–600s, and a vulcanization pressure of 5–12MPa.

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