A sulfonated polyphenylsulfone impregnated self-lubricating fabric composite and method of making the same

Abstract

The present application relates to the field of self-lubricating fabric, disclose a kind of sulfonated polyphenyl sulfone impregnated self-lubricating fabric composite and its preparation method, by PTFE / aramid fabric as matrix fiber, with sulfonated polyphenyl sulfone as matrix reinforcing resin, with evenly dispersed carbon shell microcapsule, graphite powder, whisker carbon tube as performance enhancement phase, significantly enhance the mechanical properties of gasket composite, thermodynamic properties, improve the tribological properties of composite under high load, high temperature and other environments.The preparation method uses two-step method, first by impregnating fabric to increase the mechanical properties of fiber, second by adding reinforcing additive to improve the tribological properties of fabric under high temperature, heavy load environment.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of self-lubricating fabric, in particular to a kind of sulfonated polyphenyl sulfone impregnated self-lubricating fabric composite material and preparation method thereof. BACKGROUND

[0002] Self-lubricating fabric composite material is usually made of PTFE fiber and aramid fiber fabric impregnated with phenolic resin or epoxy resin. Among them, PTFE fiber mainly plays a lubricating role, aramid fiber plays a reinforcing and wear-resistant role, and impregnated resin has the functions of bonding, fixing and bearing. In recent years, in order to further improve the performance of self-lubricating pad, researchers have carried out various modification measures. Since the fabric itself has good stability and is difficult to modify, the most widely used modification method is to improve the performance of phenolic resin, including physical blending and chemical grafting to introduce microcapsules, carbon fibers, nanomaterials and two-dimensional materials to improve the core tribological performance of the pad. However, as the impregnated matrix, phenolic resin has the problems of brittleness, low toughness, poor wear resistance, large friction coefficient, insufficient corrosion resistance and easy peeling, which limits the preservation of self-lubricating pad and its further application in heavy load, impact and high temperature environments.

[0003] It can be seen that the prior art still needs to be improved and improved. SUMMARY

[0004] In view of the shortcomings of the prior art described above, the purpose of the present application is to provide a kind of sulfonated polyphenyl sulfone impregnated self-lubricating fabric composite material and preparation method thereof, by PTFE / aramid fabric as matrix fiber, sulfonated polyphenyl sulfone as matrix reinforcing resin, and carbon shell microcapsule, graphite powder and carbon whisker as performance enhancement phase, which significantly enhances the mechanical properties and thermodynamic properties of the pad composite material and improves the tribological properties of the composite material in high load and high temperature environments.

[0005] In order to achieve the above purpose, the present application adopts the following technical scheme:

[0006] A kind of sulfonated polyphenyl sulfone impregnated self-lubricating fabric composite material, comprising PTFE and / or aramid fabric, PTFE and / or aramid fabric impregnated in sulfonated polyphenyl sulfone, and carbon shell microcapsule, graphite powder and carbon whisker uniformly dispersed in PTFE and / or aramid fabric by sulfonated polyphenyl sulfone;The inside of the carbon shell microcapsule stores lubricating oil.

[0007] The sulfonated polyphenyl sulfone impregnated self-lubricating fabric composite material, wherein the sulfonation degree of the sulfonated polyphenyl sulfone is 5-10%, and the glass transition temperature is 220-230 DEG C.

[0008] The sulfonated polyphenyl sulfone impregnated self-lubricating fabric composite material, wherein the particle size of the graphite powder is 2-5 μm.

[0009] The self-lubricating fabric composite material impregnated with sulfonated polyphenylsulfone, wherein the outer diameter of the carbon nanowhisker is 50-100 nm, the inner diameter is 2-5 nm, and the length is 1-15 μm.

[0010] A method for preparing a self-lubricating fabric composite material impregnated with sulfonated polyphenylsulfone, comprising the following steps:

[0011] S1. Preparing a sulfonated polyphenylsulfone impregnation solution: dissolving sulfonated polyphenylsulfone in an organic solvent under heating to obtain the sulfonated polyphenylsulfone impregnation solution;

[0012] S2. Impregnating fabric with sulfonated polyphenylsulfone: soaking the cleaned fabric in the sulfonated polyphenylsulfone impregnation solution and forming by scraping under heating;

[0013] S3. Preparing a sulfonated polyphenylsulfone reinforcing solution: dissolving sulfonated polyphenylsulfone in an organic solvent under heating and dispersing carbon shell microcapsules, graphite powder and carbon nanowhiskers therein to obtain the sulfonated polyphenylsulfone reinforcing solution;

[0014] S4. Forming the composite material: soaking the fabric of step S2 in the sulfonated polyphenylsulfone reinforcing solution and forming by scraping under heating to obtain the self-lubricating fabric composite material impregnated with sulfonated polyphenylsulfone.

[0015] The method for preparing the self-lubricating fabric composite material impregnated with sulfonated polyphenylsulfone, wherein the organic solvent in steps S1 and S3 is one of N-methylpyrrolidone, dimethyl sulfoxide and dimethylacetamide; the heating temperature in steps S1 and S3 is 80-100℃, and the sulfonated polyphenylsulfone is dissolved by stirring for 36-48 h.

[0016] The method for preparing the self-lubricating fabric composite material impregnated with sulfonated polyphenylsulfone, wherein the addition amount of sulfonated polyphenylsulfone in step S1 is 20-30 parts by mass; and the addition amount of the organic solvent is 100-200 parts.

[0017] The method for preparing the self-lubricating fabric composite material impregnated with sulfonated polyphenylsulfone, wherein the soaking time of the fabric in steps S2 and S4 is 20-30 minutes; the heating temperature is 110-120℃, and the forming by scraping is performed at a speed of 1-2 mm / s.

[0018] The method for preparing the self-lubricating fabric composite material impregnated with sulfonated polyphenylsulfone, wherein the addition amount of sulfonated polyphenylsulfone in step S3 is 20-30 parts by mass, the addition amount of carbon shell microcapsules is 1-2 parts, the addition amount of graphite powder is 1-2 parts, the addition amount of carbon nanowhiskers is 1-2 parts, and the addition amount of the organic solvent is 100-150 parts.

[0019] The preparation method of the sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material, wherein the preparation method of the carbon shell microcapsule in step S3 comprises the following steps: wrapping silica microspheres with phenolic resin; calcining the silica microspheres to carbonize the surface of the silica microspheres; etching the silica microspheres with a sodium hydroxide solution to obtain hollow carbon spheres; and preparing the microcapsules of the carbon shell coated with lubricating oil by using an equal-volume impregnation method.

[0020] Advantages:

[0021] The present application provides a sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material and a preparation method thereof, which significantly enhances the mechanical properties, thermodynamic properties of the lining composite material, and improves the tribological properties of the composite material under high load, high temperature and other environments by using PTFE / aramid fabric as the matrix fiber, sulfonated polyphenylsulfone as the matrix reinforcing resin, and uniformly dispersed carbon shell microcapsules, graphite powder and carbon whiskers as the performance enhancing phase. DETAILED DESCRIPTION

[0022] The present application provides a sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material and a preparation method thereof, which significantly enhances the mechanical properties, thermodynamic properties of the lining composite material, and improves the tribological properties of the composite material under high load, high temperature and other environments by using PTFE / aramid fabric as the matrix fiber, sulfonated polyphenylsulfone as the matrix reinforcing resin, and uniformly dispersed carbon shell microcapsules, graphite powder and carbon whiskers as the performance enhancing phase.

[0023] The present application provides a sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material, which comprises PTFE and / or aramid fabric, PTFE and / or aramid fabric impregnated in sulfonated polyphenylsulfone, and carbon shell microcapsules, graphite powder and carbon whiskers uniformly dispersed in the PTFE and / or aramid fabric by sulfonated polyphenylsulfone; the carbon shell microcapsules store lubricating oil in the inside.

[0024] In view of the problems of phenolic resin in self-lubricating lining, such as brittleness, low toughness, poor wear resistance, large friction coefficient, insufficient corrosion resistance and easy peeling, the present application uses sulfonated polyphenylsulfone (PPSU) to replace phenolic resin as the impregnated resin matrix for impregnating fabric lining, and enhances the fabric lining. In practical application, sulfonated polyphenylsulfone can be fully dissolved in organic solvents to form adhesive colloid, and its moderate hardness, good toughness, excellent wear resistance, high temperature resistance and other characteristics can improve the problems of phenolic resin in application.

[0025] The carbon shell microcapsule, graphite powder and carbon nanotube whisker uniformly dispersed therein serve as a performance reinforcing phase. The introduction of the reinforcing phase can significantly enhance the mechanical and thermodynamic properties of the gasket composite material (as the reinforcing phase is carbon-based, which is conducive to heat dissipation), thereby improving the tribological properties of the composite material in high-load, high-temperature and other environments.

[0026] Specifically, the shell of the carbon shell microcapsule serves as a heat conductor. The lubricating oil stored in the shell can be slowly released during material friction, and continuously supplemented to the friction interface, thereby effectively alleviating the direct contact wear of the friction surface, when the shell is broken or penetrated due to wear, pressure or temperature change.

[0027] The interlayer bonding force of the graphite powder is weak, and the graphite powder is prone to interlayer slip and transfer to the friction interface during friction, thereby forming a dense and uniform solid lubricating film. The lubricating film can reduce the contact resistance of the friction surface, and can also fill the small pits and scratches of the friction interface, thereby reducing the mechanical engagement and wear between the rough surfaces. In addition, the graphite powder has good chemical stability, and can maintain lubricating properties in high-temperature and corrosive environments, thereby further improving the applicability of the composite material in harsh working conditions. Specifically, the particle size of the graphite powder is 2-5 μm. The graphite powder with the particle size can avoid the problems of easy agglomeration due to too small particle size, and difficult mixing with the matrix in the sulfonated polyphenyl sulfone reinforced solution due to too large particle size. In addition, the particle size range is matched with the gap size of the fabric fibers and the micro-roughness of the friction interface. The graphite powder can quickly slip and transfer to the interface to form a continuous and dense solid lubricating film during friction, thereby effectively reducing the friction resistance. In addition, the rolling effect of the particles can assist in alleviating friction and wear.

[0028] The whisker carbon tube has very high tensile strength and elastic modulus, and can be uniformly dispersed in the sulfonated polyphenyl sulfone matrix in the fabric composite material, improving the load transmission and the mechanical properties such as tensile resistance, impact resistance and wear resistance of the material. At the same time, the high hardness characteristics of the whisker carbon tube can enhance the wear resistance of the friction surface and reduce the volume loss of the material during the friction process. In addition, the whisker carbon tube can also form a synergistic effect with graphite powder and carbon shell microcapsule released lubricating oil, further optimize the stability and density of the lubricating film through physical adsorption and interface combination, and improve the long-term usability of the composite material. The outer diameter of the whisker carbon tube is 50-100 nm, the inner diameter is 2-5 nm, and the length is 1-15 μm. By limiting the outer diameter, the whisker carbon tube is uniformly dispersed in the fabric, fully exerting its reinforcing effect. By limiting the inner diameter, the whisker carbon tube is given a certain hollow structure, which can not only reduce the overall density of the material, but also adsorb the lubricating oil released from the carbon shell microcapsule during the friction process, further optimizing the friction interface state. The above length limitation is adapted to the size of the fabric fiber and the thickness of the matrix, which can effectively transfer the load and inhibit crack propagation, significantly improving the mechanical properties such as tensile resistance and impact resistance of the material.

[0029] In some embodiments, the sulfonation degree of the sulfonated polyphenyl sulfone is 5-10%, and the glass transition temperature is 220°C. Compared with polyphenyl sulfone, sulfonation can improve the mechanical properties of polyphenyl sulfone. Moderate sulfonation of 5-10% can improve the interfacial bonding force between the sulfonated polyphenyl sulfone and the PTFE / aramid fabric fiber by introducing polar sulfonic acid groups. The sulfonic acid groups can form hydrogen bonds or polar interactions with the active groups on the surface of the fiber, so that the sulfonated polyphenyl sulfone can more closely coat the fiber and fill the gaps between the fabric after impregnation, reducing the interfacial voids and defects. Strengthened interfacial bonding can effectively improve the tensile strength and anti-peeling performance of the composite material. When the material is subjected to external force, the load can be efficiently transferred to the high-strength fiber matrix through the interface, thereby reducing the material fracture or deformation caused by local stress concentration. At the same time, the moderately sulfonated polyphenyl sulfone still retains most of the rigid structure of the main chain, and the interaction between the molecular chains is not excessively destroyed, which can provide the composite material with basic load-bearing and impact resistance, ensuring that the material does not easily deform under heavy load conditions.

[0030] If the sulfonation degree is too low, the number of sulfonic acid groups is insufficient, and the interfacial interaction between the sulfonated polyphenyl sulfone and the fabric fiber is weak, resulting in a decrease in the mechanical properties such as tensile resistance and anti-peeling performance of the composite material. If the sulfonation degree is too high, too many sulfonic acid groups will destroy the regularity of the polyphenyl sulfone main chain and the bonding force between the molecular chains. Because the molecular chains are excessively entangled, the sulfonated polyphenyl sulfone becomes brittle, resulting in a decrease in the rigidity and strength of the sulfonated polyphenyl sulfone, and a decrease in the bending resistance and wear resistance of the composite material.

[0031] Meanwhile, the sulfonization can increase the glass transition temperature of the PPSU (the glass transition temperature of the sulfonated polyphenylsulfone is 220-230℃, preferably 220℃), and the high glass transition temperature ensures the high temperature resistance of the material. Under the conventional working temperature or even high temperature working condition, the sulfonated polyphenylsulfone matrix always maintains the glassy rigid structure, ensuring that the self-lubricating, wear-resistant and other performances do not attenuate; meanwhile, the high temperature resistance can also reduce the thermal aging speed of the material in the high temperature environment, delay the degradation or structure damage of the molecular chain, and further prolong the service life of the composite material.

[0032] The application further provides a preparation method of the sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material, comprising the following steps:

[0033] S1. Preparing a sulfonated polyphenylsulfone impregnation solution: taking 20-30g of PPSU and 100-200mL of an organic solvent (one of N-methyl pyrrolidone (NMP), dimethyl sulfoxide (DMSO) and dimethyl acetamide (DMAc)) as a solvent into a flask. The flask is connected to a constant temperature heating and stirring device, slowly heated to 80-100℃, and at the same time, a mechanical stirring system is started, and the stirring is continuously performed for 36-48 hours until the PPSU powder is gradually dissolved, the viscosity of the system is gradually increased, and finally a uniform, flowing and smooth sulfonated polyphenylsulfone impregnation solution with brownish yellow viscosity is formed.

[0034] S2. Impregnating the sulfonated polyphenylsulfone into the fabric: the cleaned fabric is soaked in the sulfonated polyphenylsulfone impregnation solution for 20-30 minutes, and after the sulfonated polyphenylsulfone impregnation solution is fully diffused into the fiber bundle, the fabric is taken out and fixed on the bottom plate of a film coating machine, the thickness is limited to 0.3mm, the bottom plate is heated, the heating temperature is 110-120℃, and the scraping forming is performed at a speed of 1-2mm / s. This process is based on the thickness limitation of the fabric to form the thickness, mainly to remove the excess resin on the surface of the fabric, while retaining the resin inside the fabric.

[0035] S3. Preparing a sulfonated polyphenylsulfone reinforcing solution: taking 20-30g of PPSU, 1-2g of carbon shell microcapsules, 1-2g of graphite powder, 1-2g of carbon whiskers, and 100-150mL of an organic solvent (one of N-methyl pyrrolidone (NMP), dimethyl sulfoxide (DMSO) and dimethyl acetamide (DMAc)) into a clean three-necked flask, slowly heating to 80-100℃, and at the same time, a mechanical stirring system is started, and the stirring is continuously performed for 36-48 hours until the PPSU powder is gradually dissolved, the viscosity of the system is gradually increased, and finally a uniform, moderately flowing and brownish black viscous sulfonated polyphenylsulfone reinforcing solution is formed.

[0036] Specifically, the preparation method of the above-mentioned carbon shell microcapsules is as follows:

[0037] Take 700 mL of anhydrous ethanol, 100 mL of deionized water and 30 mL of concentrated ammonia water into a 1000 mL three-necked flask. Keep the temperature at 30℃, stir at 300 rpm for 15 min to mix the solution well. Then take 9.2 mL of tetrapropyl orthosilicate (TPOS) and 28.7 mL of tetraethyl orthosilicate (TEOS) and add them to the solution, keep the water bath temperature and stirring speed, and react for 30 min. Add 4 g of resorcinol and 7.62 mL of formaldehyde solution, keep the water bath temperature and stirring speed, and react for 24 h. During this period, the solution can be observed to change from milky white to coffee color to red brown, and the phenolic resin coated silica microspheres are prepared. Then use a tube furnace to calcine at 1000℃ for 5 h to obtain carbonized silica microspheres. Finally, prepare a 2 mol / L sodium hydroxide solution and etch at 80℃ under magnetic stirring for 4 h to obtain hollow carbon spheres. Use the equal volume impregnation method to prepare microcapsules of carbon shell coated lubricating oil: take 2 g of carbon shell and place it in a plastic centrifuge tube, weigh 7 g (obtained by calculating the cavity volume ratio of mesoporous carbon) of lubricating oil (such as PAO) and add it to the powder in three times, and use a glass rod to stir well during the process. Finally, rinse the powder with ethanol several times to remove excess lubricating oil, dry in an oven at 80℃ for 2 h, and then store in a glass desiccator for use.

[0038] S4. Composite material forming: soak the fabric in the sulfonated polyphenyl sulfone reinforced solution, and repeatedly extrude the surface of the fabric with a scraper to accelerate the resin impregnation efficiency. After 20-30 min, take out the fabric and fix it on the bottom plate of the film coating machine, limit the thickness to 0.35 mm, heat the bottom plate, the heating temperature is 110-120℃, and the speed is 1-2 mm / s. This process ensures that the fabric is fully impregnated and a layer of resin is reserved on the surface of the fabric to ensure the integrity of the impregnation.

[0039] In order to further illustrate the sulfonated polyphenyl sulfone impregnated self-lubricating fabric composite material and the preparation method thereof provided by the present application, the following examples and comparative examples are provided.

[0040] Example 1

[0041] First, sulfonated polyphenylsulfone infiltration solution was prepared, 20g PPSU powder, 150mL of NMP was placed in a clean three-necked flask, heated to 80°C and stirred for 48 hours to form a sulfonated polyphenylsulfone infiltration solution. The cleaned fabric was immersed in the impregnation solution, the immersion time was 20 minutes, the fabric was taken out and fixed on the bottom plate of the film coating machine, the thickness was limited to 0.3mm, the bottom plate was heated, the heating temperature was 120°C, and the scraping was formed at a speed of 1mm / s. Then, sulfonated polyphenylsulfone reinforcing solution was prepared: 20g PPSU powder, 1g carbon shell microcapsule, 1g graphite powder, 1g whisker carbon tube, 100mL of NMP was placed in a clean three-necked flask to form a sulfonated polyphenylsulfone reinforcing solution. The infiltrated fabric was soaked in the impregnation colloid, and the surface of the fabric was repeatedly scraped with a scraper, after 30 minutes, the fabric was taken out and fixed on the bottom plate of the film coating machine, the thickness was limited to 0.35mm, the bottom plate was heated, the heating temperature was 120°C, and the scraping was formed at a speed of 1mm / s.

[0042] Example 2

[0043] First, sulfonated polyphenylsulfone infiltration solution was prepared, 20g PPSU powder, 150mL of NMP was placed in a clean three-necked flask, heated to 80°C and stirred for 48 hours to form a sulfonated polyphenylsulfone infiltration solution. The cleaned fabric was immersed in the impregnation solution, the immersion time was 20 minutes, the fabric was taken out and fixed on the bottom plate of the film coating machine, the thickness was limited to 0.3mm, the bottom plate was heated, the heating temperature was 120°C, and the scraping was formed at a speed of 1mm / s. Then, sulfonated polyphenylsulfone reinforcing solution was prepared: 20g PPSU powder, 1g carbon shell microcapsule, 1g graphite powder, 1g whisker carbon tube, 100mL of NMP was placed in a clean three-necked flask to form a sulfonated polyphenylsulfone reinforcing solution. The infiltrated fabric was soaked in the impregnation colloid, and the surface of the fabric was repeatedly scraped with a scraper, after 30 minutes, the fabric was taken out and fixed on the bottom plate of the film coating machine, the thickness was limited to 0.35mm, the bottom plate was heated, the heating temperature was 120°C, and the scraping was formed at a speed of 1mm / s.

[0044] Example 3

[0045] First, sulfonated polyphenylsulfone infiltration solution was prepared by taking 30 g of PPSU powder, 200 mL of NMP into a clean three-necked flask, heating and stirring at 80 °C for 42 hours to form sulfonated polyphenylsulfone infiltration solution. The cleaned fabric was immersed in the impregnation solution for 25 minutes, and then taken out and fixed on the bottom plate of the film coating machine with a thickness of 0.3 mm. The bottom plate was heated at a temperature of 115 °C, and the fabric was coated at a speed of 1.5 mm / s. Then, sulfonated polyphenylsulfone reinforcing solution was prepared by taking 20 g of PPSU powder, 1 g of carbon shell microcapsule, 1 g of graphite powder, 2 g of carbon whisker, and 130 mL of NMP into a clean three-necked flask to form sulfonated polyphenylsulfone reinforcing solution. The infiltrated fabric was soaked in the impregnation colloid, and the surface of the fabric was repeatedly scraped with a scraper. After 30 minutes, the fabric was taken out and fixed on the bottom plate of the film coating machine with a thickness of 0.35 mm. The bottom plate was heated at a temperature of 115 °C, and the fabric was coated at a speed of 1.5 mm / s.

[0046] Example 4

[0047] First, sulfonated polyphenylsulfone infiltration solution was prepared by taking 20 g of PPSU powder, 200 mL of DMAc into a clean three-necked flask, heating and stirring at 90 °C for 42 hours to form sulfonated polyphenylsulfone infiltration solution. The cleaned fabric was immersed in the impregnation solution for 30 minutes, and then taken out and fixed on the bottom plate of the film coating machine with a thickness of 0.3 mm. The bottom plate was heated at a temperature of 120 °C, and the fabric was coated at a speed of 1.5 mm / s. Then, sulfonated polyphenylsulfone reinforcing solution was prepared by taking 25 g of PPSU powder, 2 g of carbon shell microcapsule, 2 g of graphite powder, 2 g of carbon whisker, and 100 mL of DMAc into a clean three-necked flask to form sulfonated polyphenylsulfone reinforcing solution. The infiltrated fabric was soaked in the impregnation colloid, and the surface of the fabric was repeatedly scraped with a scraper. After 25 minutes, the fabric was taken out and fixed on the bottom plate of the film coating machine with a thickness of 0.35 mm. The bottom plate was heated at a temperature of 120 °C, and the fabric was coated at a speed of 1.5 mm / s.

[0048] Comparative Example 1 (without adding reinforcing phase): basically the same as Example 1, except that the sulfonated polyphenylsulfone reinforcing solution of Comparative Example 1 only has 20 g of PPSU and 100 mL of NMP.

[0049] Comparative Example 2 (phenolic resin impregnation): basically the same as Example 1, except that phenolic resin is used instead of PPSU as sulfonated polyphenylsulfone infiltration solution and sulfonated polyphenylsulfone reinforcing solution (sulfonated polyphenylsulfone reinforcing solution: 20 g of phenolic resin powder, 1 g of carbon shell microcapsule, 1 g of graphite powder, 1 g of carbon whisker, and 100 mL of NMP).

[0050] Comparative Example 3 (without adding carbon shell microcapsules): substantially the same as Example 1, except that the sulfonated polyphenylsulfone reinforced solution in Comparative Example 3 only contains 20 g of PPSU, 1 g of graphite powder, 1 g of carbon nanotube whisker, and 100 mL of NMP.

[0051] Comparative Example 4 (without adding carbon nanotube whisker): substantially the same as Example 1, except that the sulfonated polyphenylsulfone reinforced solution in Comparative Example 4 only contains 20 g of PPSU, 1 g of carbon shell microcapsule, 1 g of graphite powder, and 100 mL of NMP.

[0052] Comparative Example 5 (only adding carbon shell microcapsule): substantially the same as Example 1, except that the sulfonated polyphenylsulfone reinforced solution in Comparative Example 5 only contains 20 g of PPSU, 1 g of carbon shell microcapsule, and 100 mL of NMP.

[0053] Performance test

[0054] (1) Strength test:

[0055] The bursting performance is a key indicator of the resistance of textile materials to local pressure or puncture force, reflecting the damage resistance of the fabric in actual use. The bursting performance test was carried out by YG026B electronic fabric strength tester according to ISO 3303-1:2012, and the results are shown in Table 1.

[0056] Table 1

[0057]

[0058] As can be seen from Table 1, the bursting strength of the pure fabric is low, only 1242N, and the bursting strength is significantly improved after impregnation of the resin of each example and each comparative example. Among them, the bursting strength of Examples 1-4 all exceeds 2000N, which is a substantial improvement compared with the pure fabric, proving that PPSU as an impregnated resin can effectively bond fabric fibers, fill gaps, and strengthen the overall structural stability. In comparison, the bursting strength of Comparative Example 1 without adding reinforcing phase is slightly lower than that of Example 1, and the strength of Comparative Examples 4 and 5 without adding carbon nanotube whisker is also lower than that of Example 1, while the bursting strength of Comparative Example 3 with graphite powder and carbon nanotube whisker is higher, indicating that carbon nanotube whisker is the key component to improve the bursting strength; carbon shell microcapsules have a slight weakening effect on the strength, but do not affect the overall performance. In addition, the bursting strength of Comparative Example 2 impregnated with phenolic resin is significantly lower than all samples impregnated with PPSU, further proving that the fabric impregnated with PPSU has higher damage resistance than traditional phenolic resin.

[0059] (2) Friction and wear test:

[0060] The fabric pads prepared were subjected to tribological test using a face contact resin lubricant friction performance evaluation tester, the motion mode was rotary sliding, the heavy load test load was 3000N, the rotating speed was 30 rpm, the room temperature, the test time was 1 h, the high temperature test was 150 °C, the test time was 1 h, the wear depth after test was tested by laser profilometer, and the results are shown in Tables 2 and 3.

[0061] Table 2 Heavy load test

[0062]

[0063] In the heavy load experiment, the friction coefficient of examples 1-4 was between 0.04-0.05, and the wear depth was between 40-50 μm, both of which were less than the comparative examples. Among them, comparative example 1 was a pad impregnated with pure sulfonated polyphenyl sulfone (PPSU), and the friction coefficient and wear depth were higher than examples 1-4 due to the absence of modified additives (reinforcing phase), indicating that the addition of carbon shell microcapsules, graphite powder and carbon whisker is beneficial to improving the lubricating performance. Comparative example 2 was a composite material prepared by using the same modification method for phenolic resin, and the friction coefficient and wear rate were higher than examples 1-4, indicating that PPSU impregnation is superior to traditional phenolic resin. The friction coefficient and wear rate of comparative examples 3-5 were greater than examples, but less than pure sulfonated polyphenyl sulfone (PPSU) impregnated pad, indicating that the coupling formulation of the three additives used in the examples has better performance.

[0064] Table 3 High temperature test

[0065]

[0066] In the high temperature test, the friction coefficient of examples 1-4 at 150 °C was stable at 0.038-0.045, and the wear depth was controlled in the range of 40-50 μm, both of which were significantly better than the comparative examples. Among them, comparative example 1 without adding reinforcing phase lacked the synergistic support of carbon shell microcapsules, graphite powder and carbon whisker, and the lubrication and wear resistance at high temperature were greatly attenuated. Comparative example 2, which was impregnated with traditional phenolic resin, performed the worst, confirming the superior high temperature stability of PPSU compared to phenolic resin. Comparative examples 3-5, which lack any reinforcing phase (such as comparative example 3 lacking microcapsules, comparative example 4 lacking carbon whisker, and comparative example 5 lacking both graphite powder and carbon whisker), although their friction and wear performance is better than comparative examples 1-2, still not as good as examples, indicating that the long-acting lubrication of carbon shell microcapsules (more easily release core material lubricating oil at high temperature), the solid lubricating film of graphite powder (stable structure at high temperature) and the mechanical enhancement of carbon whisker (suppressing wear deformation at high temperature) form a coupling effect, which together guarantees the low friction and low wear characteristics of the composite material at high temperature working conditions.

[0067] In summary, the PPSU impregnated fabric gasket of the present application adopts a two-step method, the first step increases the mechanical properties of the fibers by impregnating the fabric, and the second step improves the tribological properties of the fabric under high temperature and heavy load environment by adding reinforcing additives.

[0068] It can be understood that, for those skilled in the art, equivalent replacements or changes can be made according to the technical solutions and the inventive concept of the present application, and all these changes or replacements shall belong to the protection scope of the present application.

Claims

1. A method for preparing a sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material, characterized in that, Includes the following steps: S1. Preparation of sulfonated polyphenylsulfone impregnation solution: Sulfonated polyphenylsulfone is dissolved in an organic solvent under heating conditions to obtain a sulfonated polyphenylsulfone impregnation solution; S2. Sulfonated polyphenylsulfone impregnated fabric: The cleaned fabric is immersed in a sulfonated polyphenylsulfone impregnation solution and then coated and molded under heating conditions; S3. Preparation of sulfonated polyphenylsulfone reinforced solution: Sulfonated polyphenylsulfone is dissolved in an organic solvent under heating conditions, and carbon shell microcapsules, graphite powder and carbon whisker tubes are dispersed therein to obtain sulfonated polyphenylsulfone reinforced solution; S4. Composite material molding: The fabric from step S2 is immersed in a sulfonated polyphenylsulfone reinforcing solution and then coated and molded under heating conditions to obtain a sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material. In both steps S1 and S3, the degree of sulfonation of polyphenylene sulfone is 5-10%; in step S3, the carbon shell microcapsules contain lubricating oil.

2. The method for preparing the sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material according to claim 1, characterized in that, The organic solvents used in steps S1 and S3 are all one of N-methylpyrrolidone, dimethyl sulfoxide, and dimethylacetamide; the heating temperature in steps S1 and S3 is 80-100℃, and the sulfonated polyphenylsulfone is dissolved by stirring for 36-48 hours.

3. The method for preparing the sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material according to claim 1, characterized in that, By mass, the amount of sulfonated polyphenylene sulfone added in step S1 is 20-30 parts; the amount of organic solvent added is 100-200 parts.

4. The method for preparing the sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material according to claim 1, characterized in that, In steps S2 and S4, the fabric is soaked for 20 to 30 minutes; the heating temperature is 110 to 120°C; and the fabric is coated at a speed of 1 to 2 mm / s.

5. The method for preparing the sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material according to claim 1, characterized in that, By mass fraction, in step S3, the amount of sulfonated polyphenylene sulfone added is 20-30 parts, the amount of carbon shell microcapsules added is 1-2 parts, the amount of graphite powder added is 1-2 parts, the amount of carbon whisker tubes added is 1-2 parts, and the amount of organic solvent added is 100-150 parts.

6. The method for preparing the sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material according to claim 1, characterized in that, The preparation method of carbon-shell microcapsules in step S3 includes the following steps: encapsulating silica microspheres with phenolic resin; calcining the silica microspheres to carbonize the surface of the silica microspheres; etching the silica microspheres with sodium hydroxide solution to obtain hollow carbon spheres; and preparing microcapsules of lubricating oil with carbon shells using an equal-volume impregnation method.

7. A sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material prepared by the method for preparing the sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material according to any one of claims 1-6, characterized in that, The sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material includes PTFE and / or aramid fabric impregnated with sulfonated polyphenylsulfone, and carbon shell microcapsules, graphite powder and carbon whiskers uniformly dispersed in the sulfonated polyphenylsulfone, PTFE and / or aramid fabric.

8. The sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material according to claim 7, characterized in that, The glass transition temperature of the sulfonated polyphenylsulfone is 220–230 °C.

9. The sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material according to claim 7, characterized in that, The graphite powder has a particle size of 2–5 μm.

10. The sulfonated polyphenylsulfone impregnated self-lubricating fabric composite material according to claim 7, characterized in that, The outer diameter of the carbon whisker tube is 50–100 nm, the inner diameter is 2–5 nm, and the length is 1–15 μm.

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