High-temperature-resistant and wear-resistant composite material for building seismic isolation support and preparation method thereof

Abstract

This invention relates to the field of sliding materials for seismic isolation bearings, specifically disclosing a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings and its preparation method. The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings comprises the following raw material components in parts by weight: aliphatic polyketone, high-styrene resin-modified methyl vinyl silicone rubber, silicone resin, fluorosilicone rubber, polytetrafluoroethylene, high-temperature resistant filler, lubricant, compatibilizer, and coupling agent; the high-temperature resistant filler comprises the following raw material components: chopped basalt fiber, titanium diboride, silicon nitride, and ceramic powder. The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings prepared by this invention synergistically improves the material's wear performance, thermal stability, and compressive modulus through mechanisms such as hard embedding of filler, elastic energy absorption of rubber and plastic, and self-lubricating interface construction, thus overcoming the shortcomings of existing technologies.

Description

Technical Field

[0001] This invention relates to the field of sliding materials for building seismic isolation bearings, and particularly to a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings and its preparation method. Background Technology

[0002] In recent years, with the widespread application of long-span, multi-tower, and multi-connected continuous bridges, bridge seismic bearings have exposed a series of material-related problems under the combined conditions of strong earthquakes and long-term traffic loads. On the one hand, rubber bearings, while bearing the dead load of the superstructure and vehicle loads, need to undergo significant shear deformation during earthquakes to dissipate energy and reduce vibration. Their internal viscoelastic deformation generates significant internal heat. The sliding interfaces of friction pendulum bearings and seismic isolation bearings continuously generate frictional heat under high contact stress and large reciprocating displacement. However, traditional natural rubber, high-damping rubber, and conventional engineering plastics have low thermal conductivity and limited heat resistance. This heat is difficult to conduct and dissipate in a timely manner, leading to a rapid increase in local temperature. This can easily cause rubber softening, shear modulus and damping characteristic drift, compression creep, and accelerated thermo-oxidative aging, thereby inducing failure modes such as bearing bulging, shear instability, cracking, and delamination. On the other hand, under the coupled working conditions of "high temperature + high contact pressure + large displacement reciprocating", the wear resistance and fatigue resistance of the existing rubber and sliding plate materials are insufficient. The working surface of the support is prone to fuzzing, wear, peeling and step-like damage, which causes the friction coefficient and displacement response to fluctuate drastically with temperature and wear, resulting in the risk of uneven displacement, jamming or even failure.

[0003] To address these issues, existing technologies have developed high-damping rubber bearings by modifying formulations and adding damping resins and anti-aging additives to improve energy dissipation capacity and aging resistance. They have also widely adopted sliding materials such as PTFE and modified ultra-high molecular weight polyethylene to reduce friction and improve load-bearing capacity and wear resistance. However, the former suffers from large creep and wear under high temperature and long-term repeated heating conditions, while the latter has limited heat resistance. Therefore, it remains difficult to simultaneously meet the comprehensive service requirements of "large deformation energy dissipation, strong seismic conditions, high-temperature environments, and long-term wear."

[0004] Therefore, developing a composite rubber-plastic material that combines high temperature resistance and high wear resistance is of great significance for the development of materials for bridge bearings. Summary of the Invention

[0005] In view of this, the present invention provides a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings and a method for preparing the same.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] The first aspect of this invention provides a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings, comprising the following raw material components in parts by weight: 40-70 parts aliphatic polyketone, 10-20 parts high-polystyrene resin modified methyl vinyl silicone rubber, 10-20 parts silicone resin, 1-5 parts fluorosilicone rubber, 10-20 parts polytetrafluoroethylene, 5-15 parts high-temperature resistant filler, 1-5 parts lubricant, 1-5 parts compatibilizer, and 1-5 parts coupling agent;

[0008] The high-temperature resistant filler comprises the following raw material components: chopped basalt fiber, titanium diboride, silicon nitride, and ceramic powder.

[0009] Compared with existing technologies, the high-temperature wear-resistant composite material for building seismic isolation bearings provided by this invention uses aliphatic polyketide, high-polystyrene resin modified silicone rubber, silicone resin, fluorosilicone rubber and polytetrafluoroethylene as multiphase organic matrix. Through the synergistic construction of microstructure skeleton by high-temperature resistant fillers and additives, the high-temperature load-bearing stability, dynamic wear resistance and dimensional retention performance of the material are significantly improved, meeting the stringent requirements of deformation control, wear resistance and thermal stability of bridge structures during long-term operation.

[0010] In this invention, aliphatic polyketone serves as the primary thermoplastic matrix, providing a thermally stable load-bearing skeleton under high temperature and frictional heating conditions. Its high melting point and heat distortion temperature ensure sufficient rigidity and surface hardness, preventing the support sliding surface from softening, collapsing, or experiencing significant cold flow due to temperature rise. This maintains a stable contact stress distribution under heavy loads, high-temperature friction, and multiple cyclic operating conditions. Furthermore, aliphatic polyketone retains good wear resistance and dimensional stability even under heating conditions, forming a synergistic structure of "rigid skeleton + high-temperature resistant elastic phase" with silicone resin and fluorosilicone rubber. This prevents the rubber phase from being excessively crushed or sheared at high temperatures, ensuring the support withstands prolonged high and low temperatures. Under cyclic, frequent braking, and seismic friction conditions, it maintains a low wear rate and stable friction performance, thus significantly improving the overall thermal stability and high-temperature service reliability of bridge bearing plastics. Fluorosilicone rubber further incorporates an elastic phase resistant to high temperatures, fuel oil, and lubricating oil. Its fluorinated side chains significantly enhance the material's media stability and elasticity retention under high and low temperature cycling conditions, enabling the bearing to maintain continuous sliding and sealing protection even at high temperatures, reducing the erosion of the polyketone matrix and interface by media penetration. Silicone resin prevents fatigue pulverization or pull-out from the matrix of polystyrene-modified silicone rubber and fluorosilicone rubber under repeated high-temperature shearing, significantly improving the material's fatigue wear resistance. Simultaneously, the local cross-linking and partial inorganicization of silicone resin on the friction surface allows it to synergistically form a composite wear interface of "rigid support layer + soft lubrication layer" with the polytetrafluoroethylene transfer film, maintaining a low dynamic friction coefficient while effectively reducing the wear rate under high-temperature conditions. Polytetrafluoroethylene provides an extremely low friction coefficient and excellent anti-aging properties, significantly reducing wear and frictional heat accumulation during repeated sliding processes. Polystyrene-modified methyl vinyl silicone rubber and fluorosilicone rubber form a flexible elastic phase, which can jointly enhance high-temperature fracture strength, high-temperature stable resilience, and oil and ozone resistance.

[0011] The high-temperature resistant filler incorporates high-performance inorganic reinforcing components such as chopped basalt fiber, titanium diboride, silicon nitride, and ceramic powder to construct a multi-scale rigid support framework. Basalt fiber possesses high modulus and excellent thermal stability, enhancing the structural stiffness against compression and shear. Titanium diboride combines high hardness with high thermal conductivity, providing wear protection and thermal diffusion on load-bearing friction surfaces. Silicon nitride further enhances thermal shock resistance and dimensional accuracy, while ceramic powder forms a micro-embedding effect in the interface filling, assisting in the construction of a dense wear-resistant layer structure.

[0012] Aliphatic polyketones and polytetrafluoroethylene (PTFE) form a self-lubricating interface on the friction surface, reducing the dynamic friction coefficient. Polystyrene-modified silicone rubber can encapsulate hard, high-temperature resistant fillers, alleviating stress concentration and improving overall fracture toughness and dynamic buffering performance. Furthermore, lubricants, compatibilizers, and silane coupling agents are introduced into the formulation to improve processing fluidity, enhance multiphase interfacial adhesion, and promote uniform dispersion of inorganic fillers. This results in an overall composite system with excellent dynamic stability, durability, and green processing adaptability.

[0013] The high-temperature wear-resistant composite material for building seismic isolation bearings provided by this invention exhibits excellent dimensional retention, low wear rate and thermal stability under the high temperature, high load and slip fatigue environment of bridge bearings during long-term operation. It can significantly extend the service life of the bearings and reduce the maintenance frequency, and has broad engineering application value and industrial promotion prospects.

[0014] Preferably, the preparation method of the polystyrene resin modified methyl vinyl silicone rubber includes the following steps:

[0015] S1. Keep methyl vinyl silicone rubber at 80-100℃ for 50-70 min to obtain pretreated methyl vinyl silicone rubber.

[0016] S2. The pretreated methyl vinyl silicone rubber is impregnated in the modified mixture, and a vacuum-backfill cycle is performed to separate the solid and liquid. Under an inert atmosphere, the temperature is raised to 120-130°C in stages to carry out the polymerization reaction. After cooling, washing, and drying, the precursor is obtained. The modified mixture includes styrene, organic solvent, initiator, and stabilizer.

[0017] S3. The precursor is kept at 90-110°C for 1-2 hours to obtain the polystyrene resin modified methyl vinyl silicone rubber.

[0018] More preferably, in S2, the mass-to-volume ratio of the pretreated methyl vinyl silicone rubber to the modified mixture is 1g:2mL-1g:3mL.

[0019] More preferably, in S2, the modified mixture comprises the following raw material components in the following mass percentages: 20%-30% styrene, 45%-60% organic solvent, 5%-15% initiator and 5%-10% stabilizer.

[0020] In a further preferred embodiment, S2 includes the following steps for the segmented heating: first, heating to 75-85℃ and holding for 4-5 hours; then heating to 95-105℃ and holding for 2-3 hours; and finally heating to 120-130℃.

[0021] More preferably, in S2, the holding time for the polymerization reaction is 30-40 minutes.

[0022] More preferably, the organic solvent is toluene and ethyl acetate in a volume ratio of 1:1 to 1:2.

[0023] More preferably, the initiator is azobisisobutyronitrile.

[0024] More preferably, the stabilizer is divinylbenzene.

[0025] Preferably, the high-temperature resistant filler comprises the following raw material components in weight percentage: 20-30% chopped basalt fiber, 5%-8% titanium diboride, 20%-40% silicon nitride, and the balance ceramic powder.

[0026] Preferably, the length of the chopped basalt fibers is 0.5-1 mm;

[0027] Preferably, the titanium diboride has a particle size of 50-100 μm.

[0028] Preferably, the silicon nitride has a particle size of 10-50 μm;

[0029] Preferably, the particle size of the ceramic powder is 100-200 μm.

[0030] Preferably, the aliphatic polyketone has a melt flow rate of 3-20 g / 10 min measured at 240°C and 2.16 kg; the aliphatic polyketone has a weight-average molecular weight of 180,000-320,000 and a polydispersity index (PDI) of 2.3-3.2.

[0031] Preferably, the weight-average molecular weight of the silicone resin is 10,000-80,000.

[0032] Preferably, the polytetrafluoroethylene is polytetrafluoroethylene micro powder with a particle size of 0.5-20 μm.

[0033] Preferably, the number-average molecular weight of the fluorosilicone rubber is 3 × 10⁻⁶. 5 -1.5×10 6 The Mooney viscosity ML(1+4) at 100℃ is 30-80.

[0034] Preferably, the lubricant is methylphenyl silicone oil, methyl silicone oil, polyethylene wax, or Fischer-Tropsch wax.

[0035] Preferably, the compatibilizer is maleic anhydride-grafted polypropylene.

[0036] Preferably, the coupling agent is a titanate coupling agent.

[0037] The second aspect of the present invention provides a method for preparing the high-temperature wear-resistant composite material for building seismic isolation bearings, comprising the following steps: the high-temperature wear-resistant composite material for building seismic isolation bearings is prepared by any one of compression molding, injection molding or extrusion calendering.

[0038] Preferably, the compression molding method includes the following steps:

[0039] Step 1: Weigh each component raw material according to the design ratio, mix them evenly to obtain the mixture;

[0040] Step 2: Heat the mixture to 250-270℃ and mold it, then cool it down and remove it from the mold to obtain a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings.

[0041] Preferably, the injection molding method includes the following steps:

[0042] Step 1: Weigh aliphatic polyketone, high-styrene resin modified methyl vinyl silicone rubber, silicone resin, fluorosilicone rubber and polytetrafluoroethylene according to the design ratio, mix them evenly, keep them at 110-150℃ for 3-6 hours, mix them evenly under the conditions of barrel temperature of 240-270℃, main machine speed of 140-180rpm and feeder speed of 5-10rpm, cool, granulate, and obtain the first mixture.

[0043] Step 2: Add the first mixture to the injection molding machine, add the remaining raw material components, and inject it into the mold cavity under the conditions of injection pressure of 60-150 bar, barrel temperature of 240-270℃ and holding pressure of 50-80 bar. Hold the pressure for 100-140 seconds and extrude to obtain the high temperature and wear-resistant composite material for building seismic isolation bearings.

[0044] In a further preferred embodiment, step two also includes an injection speed of 40-50 mm / s.

[0045] In summary, this invention designs a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings. The matrix is ​​constructed using aliphatic polyketide, high-styrene resin-modified methyl vinyl silicone rubber, fluorosilicone rubber, and polytetrafluoroethylene to create a multiphase matrix structure that combines rigidity and flexibility. The wear resistance, high-temperature resistance, and dimensional stability of the material are enhanced by introducing high-temperature resistant fillers such as chopped basalt fiber, titanium diboride, silicon nitride, and ceramic powder. Simultaneously, lubricants, compatibilizers, and coupling agents are used to achieve improved processing flowability and interfacial synergistic enhancement of the composite system. This high-temperature resistant and wear-resistant composite material for building seismic isolation bearings synergistically improves friction and wear performance and thermal stability through mechanisms such as hard filler embedding, elastic energy absorption of rubber and plastic, and self-lubricating interface construction. This allows the material to maintain stable deformation and low wear rate even under long-term high-temperature sliding conditions, significantly extending the service life of bridge bearings and overcoming the shortcomings of existing technologies. Detailed Implementation

[0046] 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.

[0047] The preparation methods of the polystyrene resin modified methyl vinyl silicone rubber described in the following embodiments and comparative examples include the following steps:

[0048] S1. 500g of methyl vinyl silicone rubber is kept at 80-100℃ for 50-70min to obtain pretreated methyl vinyl silicone rubber.

[0049] S2. The pretreated methyl vinyl silicone rubber is impregnated in 1200 mL of modified mixture, and vacuum-backfill cycles are performed 3 times to separate the solid and liquid. Under an inert atmosphere, the temperature is first raised to 80°C and held for 5 h; then raised to 100°C and held for 2 h; finally, the temperature is raised to 120-130°C for polymerization reaction for 35 min. After cooling, washing, and drying, the precursor is obtained. The modified mixture includes the following raw material components in the following mass percentages: 25% styrene, 55% toluene and ethyl acetate in a volume ratio of 1:1, 12% azobisisobutyronitrile, and 8% divinylbenzene.

[0050] S3. The precursor is kept at 100°C for 1 hour to obtain the polystyrene resin modified methyl vinyl silicone rubber.

[0051] The aliphatic polyketones described in the following examples and comparative examples had a melt flow rate of 15 g / 10 min measured at 240 °C and 2.16 kg; the weight-average molecular weight of the aliphatic polyketones was 180,000, and the polydispersity index (PDI) was 2.5.

[0052] The number-average molecular weight of the fluorosilicone rubber described in the following examples and comparative examples is 1.2 × 10⁻⁶. 6 The Mooney viscosity ML(1+4) at 100℃ is 50.

[0053] The length of the short-cut basalt fibers described in the following embodiments and comparative examples is 0.6 mm;

[0054] The titanium diboride particles described in the following examples and comparative examples have a particle size of 60 μm;

[0055] The silicon nitride particles described in the following examples and comparative examples have a particle size of 30 μm;

[0056] The ceramic powder described in the following examples and comparative examples has a particle size of 150 μm.

[0057] The weight-average molecular weight of the silicone resins described in the following examples and comparative examples is 60,000.

[0058] The particle size of the polytetrafluoroethylene micropowder described in the following examples and comparative examples is 10 μm.

[0059] Unless otherwise stated, all other raw materials used in the following examples and comparative examples are commercially available products.

[0060] Example 1

[0061] This embodiment provides a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings and its preparation method, specifically including the following:

[0062] The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings comprises the following raw material components in parts by weight: 65 parts aliphatic polyketone, 18 parts polystyrene resin modified methyl vinyl silicone rubber, 14 parts silicone resin, 15 parts fluorosilicone rubber, 15 parts polytetrafluoroethylene, 10 parts high-temperature resistant filler, 3 parts methyl phenyl silicone oil, 3 parts maleic anhydride grafted polypropylene, and 2 parts titanate coupling agent.

[0063] The high-temperature resistant filler comprises the following raw material components in weight percentage: 25% chopped basalt fiber, 6% titanium diboride, 30% silicon nitride, and the balance ceramic powder.

[0064] The preparation method of the high-temperature resistant and wear-resistant composite material for building seismic isolation bearings includes the following steps:

[0065] Step 1: Weigh each component raw material according to the design ratio, mix them evenly to obtain the mixture;

[0066] Step 2: Heat the mixture to 260°C and mold it, then cool it down and remove it from the mold to obtain a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings.

[0067] Example 2

[0068] This embodiment provides a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings and its preparation method, specifically including the following:

[0069] The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings comprises the following raw material components in parts by weight: 40 parts aliphatic polyketone, 20 parts high-styrene resin modified methyl vinyl silicone rubber, 20 parts silicone resin, 20 parts fluorosilicone rubber, 20 parts polytetrafluoroethylene, 12 parts high-temperature resistant filler, 3 parts methyl phenyl silicone oil, 3 parts maleic anhydride grafted polypropylene, and 2 parts titanate coupling agent.

[0070] The high-temperature resistant filler comprises the following raw material components in weight percentage: 28% chopped basalt fiber, 5% titanium diboride, 40% silicon nitride, and the balance ceramic powder.

[0071] The preparation method of the high-temperature resistant and wear-resistant composite material for building seismic isolation bearings includes the following steps:

[0072] Step 1: Weigh each component raw material according to the design ratio, mix them evenly to obtain the mixture;

[0073] Step 2: Heat the mixture to 265°C and mold it, then cool it down and remove it from the mold to obtain a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings.

[0074] Example 3

[0075] This embodiment provides a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings and its preparation method, specifically including the following:

[0076] The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings comprises the following raw material components in parts by weight: 70 parts aliphatic polyketone, 10 parts high-styrene resin modified methyl vinyl silicone rubber, 10 parts silicone resin, 10 parts fluorosilicone rubber, 10 parts polytetrafluoroethylene, 10 parts high-temperature resistant filler, 3 parts methyl silicone oil, 3 parts maleic anhydride grafted polypropylene, and 2 parts titanate coupling agent.

[0077] The high-temperature resistant filler comprises the following raw material components in weight percentage: 30% chopped basalt fiber, 5% titanium diboride, 25% silicon nitride, and the balance ceramic powder.

[0078] The preparation method of the high-temperature resistant and wear-resistant composite material for building seismic isolation bearings includes the following steps:

[0079] Step 1: Weigh aliphatic polyketone, high-styrene resin modified methyl vinyl silicone rubber, silicone resin, fluorosilicone rubber, and polytetrafluoroethylene according to the designed proportions, mix them evenly, and keep them at 145℃ for 6 hours. Set the barrel temperature as follows: Section 1 240℃, Section 2 245℃, Section 3 250℃, Section 4 255℃, Section 5 255℃, Section 6 260℃, Section 7 260℃, Section 8 265℃, Section 9 265℃, and the die head temperature 265℃. After the barrel temperature is constant, start the main machine and set the speed to 160 rpm. Set the feeder speed to 8 rpm. The rubber strip is extruded, cooled in a water bath, and then cut and granulated by a pelletizer to obtain the first mixture.

[0080] Step 2: Add the first mixture to the injection molding machine, add the remaining raw material components, and set the barrel temperature as follows: Section 1 240℃, Section 2 245℃, Section 3 245℃, Section 4 255℃, and nozzle 255℃; close the mold and inject, with an injection pressure of 100 bar and a speed of 45 mm / s; hold pressure and cool, with a holding pressure of 60 bar and a holding time of 120 s; after cooling, open the mold and eject to obtain a high-temperature resistant and wear-resistant composite material for building vibration damping and isolation bearings.

[0081] Comparative Example 1

[0082] This comparative example provides a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings. The difference from Example 1 is that the high-styrene resin modified methyl vinyl silicone rubber is replaced with an equal amount of methyl vinyl silicone rubber, while other components and processes remain unchanged, which will not be described in detail here.

[0083] Comparative Example 2

[0084] This comparative example provides a high-temperature and wear-resistant composite material for building seismic isolation bearings. The difference from Example 1 is that the short-cut basalt fibers are replaced with an equal amount of short-cut carbon fibers, while other components and processes remain unchanged, which will not be described in detail here.

[0085] Comparative Example 3

[0086] This comparative example provides a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings. The difference from Example 1 is that aliphatic polyketone is replaced with an equal amount of ultra-high molecular weight polyethylene with a molecular weight of over 9 million. Other components and processes remain unchanged and will not be described in detail here.

[0087] To further verify the technical effects of the present invention, the high-temperature wear-resistant composite materials for building seismic isolation bearings obtained in Examples 1-3 and Comparative Examples 1-3 were tested as follows: the hardness of the samples was measured using a Shore hardness tester (referencing GB / T 2411-2008), the tensile strength and tensile modulus of elasticity were tested according to GB / T 1040.1-2018, the linear wear rate was tested according to JT / T 901-2023, the relative sliding speed for dynamic friction coefficient testing was 15 / 100 / 200 / 300 mm / s, the test temperature was 23±2℃, and the test results are shown in Table 1. In the table, / represents a failed test, indicating that the test did not reach 50 km.

[0088] Table 1. Performance test results of high-temperature and wear-resistant composite materials for building seismic isolation bearings obtained in each embodiment and comparative example at 23℃.

[0089]

[0090] As shown in Table 1, the overall performance of each embodiment under normal temperature and heavy load conditions is superior to that of the comparative example, especially Embodiment 1, which exhibits a more prominent comprehensive advantage in terms of friction reduction, wear resistance, and mechanical properties. Regarding the dynamic friction coefficients at different sliding speeds (15, 100, 200, 300 mm / s) under a load of 45 MPa, Embodiment 1 has coefficients of 0.063, 0.062, 0.058, and 0.058, respectively, with the overall friction coefficient remaining stable within the range of 0.06 ± 10%, showing stability and minimal fluctuation. In contrast, Comparative Example 1, under the same conditions, has coefficients of 0.076, 0.071, 0.068, and 0.065, respectively, which are significantly higher than those of Embodiment 1, especially at low and medium speeds, indicating weaker friction reduction capabilities under boundary and mixed lubrication conditions. Although the friction coefficients of Comparative Example 2 (0.065, 0.064, 0.062, 0.059) are close to those of Embodiment 1, they are still slightly higher overall. Comparative Example 3 has the highest friction coefficient at low speed (0.081), indicating that it has poor friction control under low-speed heavy load conditions.

[0091] Secondly, regarding wear resistance, the linear wear rate of Example 1 was 9.86 μm / km, significantly lower than that of Comparative Example 1 (25.01 μm / km), with a wear reduction of over 60%, indicating that Example 1 has significantly superior wear resistance. Compared to Comparative Example 2 (13.38 μm / km), Example 1 also exhibited a lower wear level, indicating better stability under long-distance operating conditions. Comparative Example 3 did not provide wear data, indicating that it failed to complete the 50km wear test under high-load, grease-free lubrication conditions, and its wear resistance was far lower than that of Comparative Example 1.

[0092] In terms of mechanical properties, the tensile strength of Example 1 was 56.6 MPa, significantly higher than that of Comparative Example 1 (52.1 MPa) and Comparative Example 3 (32.5 MPa); the tensile modulus of elasticity was 1568 MPa, also significantly higher than that of Comparative Example 1 (1368 MPa) and Comparative Example 3 (705 MPa). Regarding Shore hardness, Example 1 had a hardness of 75D, higher than that of Comparative Example 1 (69D), and exhibited a higher or more stable hardness level compared to Comparative Examples 2 and 3. This indicates that Example 1, while maintaining a low coefficient of friction, still possesses high rigidity and load-bearing capacity, achieving a synergistic improvement in strength, stiffness, and wear resistance.

[0093] In summary, the high-temperature wear-resistant composite material for building seismic isolation bearings provided by the embodiments of the present invention exhibits a stable coefficient of friction, a lower linear wear rate, and higher mechanical properties, demonstrating the optimized advantages of the material system in terms of structural strengthening and lubrication wear resistance mechanisms, and has better stability and reliability in engineering applications.

[0094] Table 2 shows the performance test results of high-temperature and wear-resistant composite materials for building seismic isolation bearings obtained in each example and comparative example at 150℃.

[0095]

[0096] As shown in Table 2, under the conditions of 150℃ and 45MPa load, the friction and mechanical properties of each embodiment are superior and more stable than those of the comparative example. Regarding the coefficients of friction at different sliding speeds (15, 100, 200, 300 mm / s), Embodiment 1 has coefficients of friction of 0.052, 0.050, 0.050, and 0.048, respectively, demonstrating good high-temperature friction stability. The coefficients of friction of Comparative Example 1 are 0.063, 0.061, 0.059, and 0.052, respectively, which are significantly higher than those of Embodiment 1, especially in the low and medium speed ranges, indicating weaker friction reduction ability under high-temperature conditions. Although the coefficients of friction of Comparative Example 2 (0.058, 0.054, 0.052, 0.051) are close to those of Embodiment 1, they are still slightly higher overall. The friction coefficient of Comparative Example 3 is abnormally low (0.014-0.021). However, combined with its mechanical property data, it can be seen that the material has shown significant performance degradation at high temperatures. The decrease in friction coefficient may be due to material softening or structural instability, and is not a truly excellent wear-resistant and friction-reducing performance.

[0097] In terms of mechanical properties, the tensile strength of Example 1 is 49.7 MPa, which is significantly higher than that of Comparative Example 1 (44.5 MPa) and also much higher than that of Comparative Example 3 (26.5 MPa). The tensile modulus of elasticity of Example 1 is 1252 MPa, which is higher than that of Comparative Example 1 (1114 MPa) and significantly better than that of Comparative Example 3 (147 MPa).

[0098] In terms of hardness, Example 1 has a hardness of 65D, which is also higher than Comparative Example 1 (59D) and Comparative Example 3 (35D). This indicates that Example 1 can still maintain good structural integrity and load-bearing capacity under high temperature conditions. Although Comparative Example 2 is close to Example 1 in terms of tensile strength (48.8 MPa) and elastic modulus (1269 MPa), its coefficient of friction is slightly higher overall, and its overall performance is still slightly inferior to Example 1.

[0099] Comprehensive analysis shows that, under high-temperature conditions of 150℃, the high-temperature resistant and wear-resistant composite material for building seismic isolation bearings provided in this embodiment of the invention not only maintains a low and stable coefficient of friction, but also possesses high strength, modulus and hardness, achieving a good match between tribological and mechanical properties.

[0100] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-temperature resistant and wear-resistant composite material for building seismic isolation bearings, characterized in that, The raw material components include the following parts by weight: 40-70 parts aliphatic polyketone, 10-20 parts high-styrene resin modified methyl vinyl silicone rubber, 10-20 parts silicone resin, 1-5 parts fluorosilicone rubber, 10-20 parts polytetrafluoroethylene, 5-15 parts high-temperature resistant filler, 1-5 parts lubricant, 1-5 parts compatibilizer, and 1-5 parts coupling agent; The high-temperature resistant filler comprises the following raw material components: chopped basalt fiber, titanium diboride, silicon nitride, and ceramic powder; The preparation method of the polystyrene resin modified methyl vinyl silicone rubber includes the following steps: S1. Keep methyl vinyl silicone rubber at 80-100℃ for 50-70 min to obtain pretreated methyl vinyl silicone rubber. S2. The pretreated methyl vinyl silicone rubber is impregnated in the modified mixture, and a vacuum-backfill cycle is performed to separate the solid and liquid. Under an inert atmosphere, the temperature is raised to 120-130°C in stages to carry out the polymerization reaction. After cooling, washing, and drying, the precursor is obtained. The modified mixture includes styrene, organic solvent, initiator, and stabilizer. S3. The precursor is kept at 90-110℃ for 1-2 hours to obtain the polystyrene resin modified methyl vinyl silicone rubber.

2. The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings as described in claim 1, characterized in that, In S2, the mass-to-volume ratio of the pretreated methyl vinyl silicone rubber to the modified mixture is 1g:2mL-1g:3mL; In S2, the modified mixture comprises the following raw material components in the following mass percentages: 20%-30% styrene, 45%-60% organic solvent, 5%-15% initiator and 5%-10% stabilizer. In S2, the specific steps of the segmented heating are as follows: first, heat to 75-85℃ and hold for 4-5 hours; then heat to 95-105℃ and hold for 2-3 hours; finally, heat to 120-130℃. In S2, the holding time for the polymerization reaction is 30-40 minutes.

3. The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings as described in claim 1 or 2, characterized in that, The organic solvent is toluene and ethyl acetate in a volume ratio of 1:1 to 1:2; The initiator is azobisisobutyronitrile; The stabilizer is divinylbenzene.

4. The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings as described in claim 1, characterized in that: The high-temperature resistant filler comprises the following raw material components in the following mass percentages: 20%-30% chopped basalt fiber, 5%-8% titanium diboride, 20%-40% silicon nitride, and the balance being ceramic powder.

5. The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings as described in claim 4, characterized in that: The length of the short-cut basalt fibers is 0.5-1 mm; The titanium diboride has a particle size of 50-100 μm; The silicon nitride has a particle size of 10-50 μm; The ceramic powder has a particle size of 100-200 μm.

6. The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings as described in claim 1, characterized in that: The aliphatic polyketone had a melt flow rate of 3-20 g / 10 min measured at 240℃ and 2.16 kg; the weight-average molecular weight of the aliphatic polyketone was 180,000-320,000, and the polydispersity index (PDI) was 2.3-3.

2. The weight-average molecular weight of the silicone resin is 10,000-80,000; The polytetrafluoroethylene is polytetrafluoroethylene micro powder with a particle size of 0.5-20μm.

7. The high-temperature resistant and wear-resistant composite material for building seismic isolation bearings as described in claim 1, characterized in that: The lubricant is methylphenyl silicone oil, methyl silicone oil, polyethylene wax or Fischer-Tropsch wax; The compatibilizer is maleic anhydride-grafted polypropylene. The coupling agent is a titanate coupling agent.

8. A method for preparing a high-temperature resistant and wear-resistant composite material for building seismic isolation bearings as described in any one of claims 1-7, characterized in that: The process includes the following steps: the high-temperature resistant and wear-resistant composite material for the building seismic isolation bearing is prepared by any one of the following methods: compression molding, injection molding, or extrusion calendering.

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