A CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material, a preparation method and applications thereof

Abstract

The application discloses a CMC / fluorosilane synergistically modified carbon fiber reinforced resin-based friction material, a preparation method and application, and relates to the technical field of friction materials.The friction material comprises the following components in percentage by mass: 10-25% of thermosetting resin, 15-35% of modified carbon fiber, and 40-75% of an adjusting agent, with the total being 100%; the modified carbon fiber is obtained by synergistically grafting modification of carbon fiber by CMC and fluorosilane.The carbon fiber is synergistically grafted and modified by CMC and fluorosilane, so that the surface energy of the material can be reduced without damaging the fiber strength, the adhesion between the friction material, the counterpart and the abrasive particles is reduced, and the friction and wear performance of the carbon fiber reinforced resin-based material is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of friction materials, and in particular to a CMC / fluorosilane synergistically non-destructively modified carbon fiber reinforced resin-based friction material, a preparation method and an application thereof. Background Art

[0002] Carbon fiber-reinforced resin-based friction materials, composed of carbon fibers, thermosetting resins, and friction modifiers, are widely used in brakes, clutches, and friction transmissions for various transportation vehicles and machinery due to their excellent friction and wear properties, high specific strength, and wide design flexibility. However, during transmission / braking, especially under high loads, adhesion between the friction material and the mating pair and the accumulation of wear debris on the material surface deteriorate the friction material's surface condition, resulting in severe wear and affecting normal equipment operation. Furthermore, traditional carbon fiber surface treatment methods often adversely affect the fiber's mechanical properties (such as high temperatures or acid oxidation) or are cumbersome and unsuitable for large-scale production (e.g., various coatings). Therefore, the development of new carbon fiber-reinforced resin-based friction materials with low adhesion and long lifespan is of great significance.

[0003] The carbon fiber surface modification method that breaks the shackles of resin matrix to composite material interface strength is disclosed in the prior art, and this method utilizes template method to prepare hollow capsule and is applied to oxidized carbon fiber surface, makes it while optimizing composite material interface, effectively strengthens the matrix in composite material, improves the interface and interlaminar shear strength of composite material.But it adopts acidic solution oxidation carbon fiber, destroys the fiber itself structure, reduces fiber strength, and has a negative impact on environment.Meanwhile, those skilled in the art use fluorosilane modified hydrophobic carbon fiber, fluorinated polyurethane, activated carbon etc. as hydrophobic coating, use polyvinyl acetate emulsion, isophorone diamine etc. as composite adhesive, apply adhesive and hydrophobic coating on cable surface after cleaning, finally cover a layer of zinc oxide on its surface.Gained surface effectively reduces cable surface energy and improves its hydrophobicity, but wherein the manufacturing process of hydrophobic carbon fiber is long and required temperature is high, and process is complicated. Summary of the Invention

[0004] To address the shortcomings of the aforementioned background technologies, the present invention primarily utilizes a simpler process flow to reduce the material's surface energy without compromising the carbon fiber's strength, thereby enhancing the friction and wear properties of carbon fiber-reinforced resin-based materials. The present invention provides a CMC / fluorosilane synergistically non-destructively modified carbon fiber-reinforced resin-based friction material, as well as a preparation method and application. In this friction material, CMC and fluorosilane are synergistically grafted onto the carbon fibers, reducing the material's surface energy without compromising fiber strength, reducing adhesion between the friction material, the mating pair, and the abrasive particles, and enhancing the friction and wear properties of the carbon fiber-reinforced resin-based material.

[0005] The first object of the present invention is to provide a CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material, the friction material comprising the following components by mass percentage: 10-25% thermosetting resin, 15-35% modified carbon fiber, 40-75% regulator, totaling 100%;

[0006] The modified carbon fiber is obtained by synergistically grafting CMC and fluorosilane on the carbon fiber;

[0007] The regulator includes one or more of alumina, kaolin, calcium sulfate whisker, carbon black, diatomaceous earth, graphite, black rubber powder, sublimated sulfur, nitrile rubber, hematite, barite, and limestone.

[0008] Preferably, the thermosetting resin includes one or more of modified phenolic resin, epoxy resin, cyanate ester, bismaleimide, and vinyl ester.

[0009] Preferably, the carbon fiber is one or more of polyacrylonitrile-based carbon fiber, asphalt-based carbon fiber, and viscose-based carbon fiber; wherein the carbon fiber has a length of 1-20 microns.

[0010] Preferably, the fluorosilane includes one or more of 1H,1H,2H,2H-perfluorooctyltrichlorosilane, trifluoropropylmethyl silicone oil, and polydimethylsiloxane.

[0011] Preferably, the modified carbon fiber is prepared according to the following steps:

[0012] Add CMC powder to deionized water and stir at 60-80°C for 90-120 minutes to obtain CMC solution;

[0013] Immerse the carbon fiber in the CMC solution and let it stand at 60-80°C for 30-90 minutes to obtain activated carbon fiber;

[0014] dissolving fluorosilane in acetone to obtain a fluorosilane-acetone solution;

[0015] The activated carbon fibers are immersed in a fluorosilane-acetone solution, and then ammonia water is added and stirred, and then the solvent is removed to obtain modified carbon fibers.

[0016] Preferably, the concentration of the fluorosilane-acetone solution is 1-10 g / L.

[0017] Preferably, the amount of ammonia water added is 1 ml of ammonia water per 20-60 ml of fluorosilane-acetone solution.

[0018] A second object of the present invention is to provide a method for preparing a CMC / fluorosilane synergistically non-destructively modified carbon fiber reinforced resin-based friction material, characterized in that it comprises the following steps:

[0019] Weigh thermosetting resin, modified carbon fiber and regulator according to proportion, mix and stir to obtain a mixture;

[0020] The mixture is placed in a mold, and after hot pressing, curing and heat treatment, a CMC / fluorosilane synergistically non-destructive modified carbon fiber reinforced resin-based friction material is obtained.

[0021] Preferably, during the hot pressing curing process, the pressure is set to 5-10 MPa, the temperature is 150-170°C, the hot pressing time is 10-15 min, and the air is released every 50-100 s during the hot pressing curing period;

[0022] During the heat treatment process,

[0023] Start heating from room temperature to 100-130°C for 20-30 minutes and then keep warm for 40-60 minutes;

[0024] Continue heating for 20-30 minutes to 160-180°C and keep warm for 70-90 minutes;

[0025] Continue heating for 5-20 minutes to 185-190°C and keep warm for 30-40 minutes;

[0026] Then heat it up to 195-200°C for 20-30 min, keep it warm for 50-80 min, and finally cool it to room temperature in a blast drying oven.

[0027] The third object of the present invention is to provide a CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material for use in brakes, clutches or friction transmission devices.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] This invention provides a carbon fiber-reinforced resin-based friction material that is synergistically modified with CMC and fluorosilane, as well as a preparation method and application. The invention utilizes CMC and fluorosilane to synergistically and non-destructively modify carbon fibers, and the modified carbon fibers are then used to prepare the carbon fiber-reinforced resin-based friction material. CMC forms a thin film rich in active groups such as hydroxyl and carboxyl groups on the carbon fiber surface. These groups provide numerous attachment sites for fluorosilane grafting, effectively reducing the material's surface energy.

[0030] The process provided by the present invention is simple and has a short cycle, avoiding the damage to carbon fiber caused by traditional activation methods (nitric acid etching, high-temperature oxidation, etc.). The modified low-surface-energy carbon fiber reduces the adhesion of the material to wear debris during the friction process, improves the friction stability of the material, and significantly reduces the wear rate of the friction material and metal.

[0031] The CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material prepared by the present invention reduces the wear rate by 27-53%, the surface energy by 39-53%, and the wear rate of the metal pair by 46-75%. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a comparison chart of the wear rates of the CMC / fluorosilane synergistically non-destructive modified carbon fiber reinforced resin-based friction material prepared in the present invention and the metal dual wear rate.

[0033] Figure 2 This is a comparison chart of the surface energy after grinding of the CMC / fluorosilane synergistically non-destructively modified carbon fiber reinforced resin-based friction material prepared by the present invention. DETAILED DESCRIPTION

[0034] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the present invention is further described below with reference to specific embodiments and drawings, but the embodiments are not intended to limit the present invention.

[0035] The first aspect of the present invention provides a CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material, the friction material comprising the following components in percentage by weight: 10-25% thermosetting resin, 15-35% modified carbon fiber, 40-75% regulator, totaling 100%;

[0036] The modified carbon fiber is obtained by synergistically grafting carboxymethyl cellulose (CMC) and fluorosilane onto the carbon fiber;

[0037] The regulator includes one or more of alumina, kaolin, calcium sulfate whisker, carbon black, diatomaceous earth, graphite, black rubber powder, sublimated sulfur, nitrile rubber, hematite, barite, and limestone.

[0038] This invention primarily utilizes CMC / fluorosilane for synergistic, non-destructive modification of carbon fibers, and uses the modified carbon fibers in the preparation of carbon fiber-reinforced resin-based friction materials. CMC forms a thin film rich in reactive groups, such as hydroxyl and carboxyl groups, on the carbon fiber surface. These groups provide numerous attachment sites for fluorosilane grafting, effectively reducing the material's surface energy. The synergistic grafting modification of carbon fibers with CMC and fluorosilane reduces the material's surface energy without compromising fiber strength, minimizing adhesion between the friction material, the mating pair, and abrasive particles, and improving the friction and wear performance of carbon fiber-reinforced resin-based materials.

[0039] The thermosetting resin includes one or more of modified phenolic resin, epoxy resin, cyanate ester, bismaleimide, and vinyl ester.

[0040] The carbon fiber is one or more of polyacrylonitrile-based carbon fiber, asphalt-based carbon fiber, and viscose-based carbon fiber; wherein the carbon fiber has a length of 1-20 microns.

[0041] The fluorosilane includes one or more of 1H,1H,2H,2H-perfluorooctyltrichlorosilane, trifluoropropylmethyl silicone oil, and polydimethylsiloxane.

[0042] Specifically, the modified carbon fiber is prepared according to the following steps:

[0043] Add CMC powder to deionized water and stir at 60-80°C for 90-120 minutes to obtain a CMC solution; the concentration of the CMC solution is 1-4 g / L.

[0044] Immerse the carbon fiber in the CMC solution and let it stand at 60-80°C for 30-90 minutes to obtain activated carbon fiber;

[0045] dissolving fluorosilane in acetone to obtain a fluorosilane-acetone solution;

[0046] The activated carbon fibers were immersed in a fluorosilane-acetone solution, and then ammonia water was added and stirred for 2 to 8 hours, and then the solvent was removed to obtain modified carbon fibers.

[0047] The concentration of the fluorosilane-acetone solution is 1-10 g / L.

[0048] The amount of ammonia water added is 1 ml of ammonia water to every 20-60 ml of fluorosilane-acetone solution; after adding ammonia water and stirring, the solvent is removed to obtain the modified carbon fiber.

[0049] A second aspect of the present invention provides a method for preparing a CMC / fluorosilane synergistically non-destructively modified carbon fiber reinforced resin-based friction material, comprising the following steps:

[0050] Weigh thermosetting resin, modified carbon fiber and regulator according to proportion, mix and stir to obtain a mixture;

[0051] The mixture is placed in a mold, and after hot pressing, curing and heat treatment, a CMC / fluorosilane synergistically non-destructive modified carbon fiber reinforced resin-based friction material is obtained.

[0052] Wherein, during the hot pressing curing process, the pressure is set to 5-10 MPa, the temperature is 150-170 ° C, the hot pressing time is 10-15 min, and the air is released every 50-100 s during the hot pressing curing period;

[0053] During the heat treatment process, the temperature is raised from room temperature to 100-130°C for 20-30 minutes and then kept warm for 40-60 minutes; the temperature is further raised to 160-180°C for 20-30 minutes and kept warm for 70-90 minutes; the temperature is further raised to 185-190°C for 5-20 minutes and kept warm for 30-40 minutes; the temperature is further raised to 195-200°C for 20-30 minutes and kept warm for 50-80 minutes, and finally cooled to room temperature in a blast drying oven.

[0054] The preparation method provided by the present invention is simple and has a short cycle, avoiding the damage to carbon fiber caused by traditional activation methods (nitric acid etching, high-temperature oxidation, etc.). The modified low-surface-energy carbon fiber reduces the adhesion of the material to wear debris during the friction process, improves the friction stability of the material, and significantly reduces the wear rate of the friction material and metal.

[0055] A third aspect of the present invention provides an application of a CMC / fluorosilane synergistically non-destructively modified carbon fiber reinforced resin-based friction material in a brake, clutch or friction transmission device.

[0056] It should be noted that the experimental methods used in the present invention are all conventional methods unless otherwise specified; the reagents and materials used are all commercially available unless otherwise specified.

[0057] Example 1

[0058] Step 1: Dissolve 1.5 g of CMC in 1 L of deionized water, heat and stir at 80° C. for 90 min to obtain a CMC solution;

[0059] Step 2: immerse 20 g of polyacrylonitrile-based carbon fiber in the solution of step 1, heat it at 80° C. for 30 min, remove the solution, and then dry the carbon fiber in an electric blast drying oven to obtain activated carbon fiber;

[0060] Step 3: Dissolve 1g of 1H,1H,2H,2H-perfluorooctyltrichlorosilane in 1L of acetone, immerse 20g of activated carbon fiber in the solution, add 35ml of 25% ammonia water, and stir for 3h. Remove the solvent, rinse with deionized water, and dry to obtain the modified carbon fiber.

[0061] Step 4: Accurately weigh 20g of modified carbon fiber, 15g of cashew nut shell liquid-modified phenolic resin, 5g of aramid pulp, 1g of carbon black, 7g of nitrile rubber, 1g of sublimed sulfur, 5g of calcined alumina, 10g of barite, 20g of fluorite, and 16g of limestone. Place the above raw materials in a high-speed mixer and mix them at 2000 rpm for 5 times, each time for 3 seconds, with a 5-minute interval between two mixings to obtain a mixture;

[0062] Step 5, weigh 15.44 g of the mixture obtained in step 4 and place it in a mold, place it on a hot press, set the pressure to 5 MPa, the temperature to 170°C, the hot pressing time to 10 min, release the air once every 50 s during hot pressing curing, and release the air once every 100 s after 400 s, and obtain a semi-finished product after hot pressing curing; place the semi-finished product in an electric hot air drying oven for heat treatment, the procedure is: start from room temperature to 125°C for 20 min and then keep warm for 50 min; continue to heat up to 170°C for 20 min and keep warm for 80 min; continue to heat up to 185°C for 10 min and keep warm for 35 min; heat up to 200°C for another 20 min and keep warm for 60 min, and finally cool to room temperature with a blast drying oven to obtain a modified carbon fiber reinforced resin-based friction material.

[0063] Example 2

[0064] Step 1: Dissolve 1.5 g of CMC in 1 L of deionized water, heat and stir at 80° C. for 90 min to obtain a CMC solution;

[0065] Step 2: immerse 20 g of polyacrylonitrile-based carbon fiber in the solution of step 1, heat it at 80° C. for 30 min, remove the solution, and dry the carbon fiber in an electric blast drying oven to obtain activated carbon fiber;

[0066] Step 3: Dissolve 2g of 1H,1H,2H,2H-perfluorooctyltrichlorosilane in 1L of acetone, immerse 20g of activated carbon fiber in the solution, add 35ml of 25% ammonia water, and stir for 3h. Remove the solvent, rinse with deionized water, and dry to obtain the modified carbon fiber.

[0067] Step 4: Accurately weigh 20g of modified carbon fiber, 15g of cashew nut shell liquid-modified phenolic resin, 5g of aramid pulp, 1g of carbon black, 7g of nitrile rubber, 1g of sublimed sulfur, 5g of calcined alumina, 10g of barite, 20g of fluorite, and 16g of limestone. Place the above raw materials in a high-speed mixer and mix them at 2000 rpm for 5 times, each time for 3 seconds, with a 5-minute interval between two mixings to obtain a mixture;

[0068] Step 5, weigh 15.44 g of the mixture obtained in step 4 and place it in a mold, place it on a hot press, set the pressure to 5 MPa, the temperature to 170°C, the hot pressing time to 10 min, release the air once every 50 s during hot pressing curing, and release the air once every 100 s after 400 s, and obtain a semi-finished product after hot pressing curing; place the semi-finished product in an electric hot air drying oven for heat treatment, the procedure is: start from room temperature to 125°C for 20 min and then keep warm for 50 min; continue to heat up to 170°C for 20 min and keep warm for 80 min; continue to heat up to 185°C for 10 min and keep warm for 35 min; heat up to 200°C for another 20 min and keep warm for 60 min, and finally cool to room temperature with a blast drying oven to obtain a modified carbon fiber reinforced resin-based friction material.

[0069] Example 3

[0070] Step 1: Dissolve 1.5 g of CMC in 1 L of deionized water, heat and stir at 80° C. for 90 min to obtain a CMC solution;

[0071] Step 2: immerse 20 g of polyacrylonitrile-based carbon fiber in the solution of step 1, heat it at 80° C. for 30 min, remove the solution, and dry the carbon fiber in an electric blast drying oven to obtain activated carbon fiber;

[0072] Step 3: Dissolve 3g of 1H,1H,2H,2H-perfluorooctyltrichlorosilane in 1L of acetone, immerse 20g of activated carbon fiber in the solution, add 35ml of 25% ammonia water, and stir for 3h. Remove the solvent, rinse with deionized water, and dry to obtain the modified carbon fiber.

[0073] Step 4: Accurately weigh 20g of modified carbon fiber, 15g of cashew nut shell liquid-modified phenolic resin, 5g of aramid pulp, 1g of carbon black, 7g of nitrile rubber, 1g of sublimed sulfur, 5g of calcined alumina, 10g of barite, 20g of fluorite, and 16g of limestone. Place the above raw materials in a high-speed mixer and mix them at 2000 rpm for 5 times, each time for 3 seconds, with a 5-minute interval between two mixings to obtain a mixture;

[0074] Step 5, weigh 15.44 g of the mixture obtained in step 4 and place it in a mold, place it on a hot press, set the pressure to 5 MPa, the temperature to 170°C, the hot pressing time to 10 min, release the air once every 50 s during hot pressing curing, and release the air once every 100 s after 400 s, and obtain a semi-finished product after hot pressing curing; place the semi-finished product in an electric hot air drying oven for heat treatment, the procedure is: start from room temperature to 125°C for 20 min and then keep warm for 50 min; continue to heat up to 170°C for 20 min and keep warm for 80 min; continue to heat up to 185°C for 10 min and keep warm for 35 min; heat up to 200°C for another 20 min and keep warm for 60 min, and finally cool to room temperature with a blast drying oven to obtain a modified carbon fiber reinforced resin-based friction material.

[0075] Example 4

[0076] Step 1: Dissolve 1.5 g of CMC in 1 L of deionized water, heat and stir at 80° C. for 90 min to obtain a CMC solution;

[0077] Step 2: immerse 20 g of polyacrylonitrile-based carbon fiber in the solution of step 1, heat it at 80° C. for 30 min, remove the solution, and then dry the carbon fiber in an electric blast drying oven to obtain activated carbon fiber;

[0078] Step 3: Dissolve 4g of 1H,1H,2H,2H-perfluorooctyltrichlorosilane in 1L of acetone, immerse 20g of activated carbon fiber in the solution, add 35ml of 25% ammonia water, and stir for 3h. Remove the solvent, rinse with deionized water, and dry to obtain the modified carbon fiber.

[0079] Step 4: Accurately weigh 20g of modified carbon fiber, 15g of cashew nut shell liquid-modified phenolic resin, 5g of aramid pulp, 1g of carbon black, 7g of nitrile rubber, 1g of sublimed sulfur, 5g of calcined alumina, 10g of barite, 20g of fluorite, and 16g of limestone. Place the above raw materials in a high-speed mixer and mix them at 2000 rpm for 5 times, each time for 3 seconds, with a 5-minute interval between two mixings to obtain a mixture;

[0080] Step 5, weigh 15.44 g of the mixture obtained in step 4 and place it in a mold, place it on a hot press, set the pressure to 5 MPa, the temperature to 170°C, the hot pressing time to 10 min, release the air once every 50 s during hot pressing curing, and release the air once every 100 s after 400 s, and obtain a semi-finished product after hot pressing curing; place the semi-finished product in an electric hot air drying oven for heat treatment, the procedure is: start from room temperature to 125°C for 20 min and then keep warm for 50 min; continue to heat up to 170°C for 20 min and keep warm for 80 min; continue to heat up to 185°C for 10 min and keep warm for 35 min; heat up to 200°C for another 20 min and keep warm for 60 min, and finally cool to room temperature with a blast drying oven to obtain a modified carbon fiber reinforced resin-based friction material.

[0081] Comparative Example 1

[0082] Step 1: Accurately weigh 20g of polyacrylonitrile-based carbon fiber, 15g of cashew nut shell liquid-modified phenolic resin, 5g of aramid pulp, 1g of carbon black, 7g of nitrile rubber, 1g of sublimed sulfur, 5g of calcined alumina, 10g of barite, 20g of fluorite, and 16g of limestone. Place the above raw materials in a high-speed mixer and mix them at 2000rpm for 5 times, each time for 3 seconds, with a 5-minute interval between two mixings to obtain a mixture;

[0083] Step 2: Weigh 15.44 g of the mixture obtained in step 1 and place it in a mold, which is then placed on a hot press. The pressure is set to 5 MPa, the temperature is 170°C, the hot pressing time is 10 min, and the air is released every 50 s during hot pressing curing. After 400 s, the air is released every 100 s to obtain a semi-finished product after hot pressing curing. The semi-finished product is placed in an electric blast drying oven for heat treatment. The procedure is as follows: start heating from room temperature to 125°C for 20 min and then keep warm for 50 min; continue heating to 170°C for 20 min and keep warm for 80 min; continue heating to 185°C for 10 min and keep warm for 35 min; then heat to 200°C for 20 min and keep warm for 60 min, and finally cool to room temperature with a blast drying oven to obtain a modified carbon fiber reinforced resin-based friction material.

[0084] Comparative Example 2

[0085] Step 1: Dissolve 1.5 g of CMC in 1 L of deionized water, heat and stir at 80° C. for 90 min to obtain a CMC solution;

[0086] Step 2: immerse 20 g of polyacrylonitrile-based carbon fiber in the solution of step 1, heat it at 80° C. for 30 min, remove the solution, and dry the carbon fiber in an electric blast drying oven to obtain activated carbon fiber;

[0087] Step 3: Accurately weigh 20g of modified carbon fiber, 15g of cashew nut shell liquid-modified phenolic resin, 5g of aramid pulp, 1g of carbon black, 7g of nitrile rubber, 1g of sublimed sulfur, 5g of calcined alumina, 10g of barite, 20g of fluorite, and 16g of limestone. Place the above raw materials in a high-speed mixer and mix them at 2000 rpm for 5 times, each time for 3 seconds, with a 5-minute interval between two mixings to obtain a mixture;

[0088] Step 4, weigh 15.44 g of the mixture obtained in step 4 and place it in a mold, place it on a hot press, set the pressure to 5 MPa, the temperature to 170°C, the hot pressing time to 10 min, release the air once every 50 s during hot pressing curing, and release the air once every 100 s after 400 s, and obtain a semi-finished product after hot pressing curing; place the semi-finished product in an electric hot air drying oven for heat treatment, the procedure is: start from room temperature to 125°C for 20 min and then keep warm for 50 min; continue to heat up to 170°C for 20 min and keep warm for 80 min; continue to heat up to 185°C for 10 min and keep warm for 35 min; heat up to 200°C for another 20 min and keep warm for 60 min, and finally cool to room temperature with a blast drying oven to obtain a modified carbon fiber reinforced resin-based friction material.

[0089] Comparative Example 3

[0090] Step 1: Dissolve 3g of 1H,1H,2H,2H-perfluorooctyltrichlorosilane in 1L of acetone, immerse 20g of polyacrylonitrile-based carbon fiber in the solution, add 35ml of 25% ammonia water, and stir for 3 hours. Remove the solvent, rinse with deionized water, and dry to obtain the modified carbon fiber.

[0091] Step 2: Accurately weigh 20g of modified carbon fiber, 15g of cashew nut shell liquid-modified phenolic resin, 5g of aramid pulp, 1g of carbon black, 7g of nitrile rubber, 1g of sublimed sulfur, 5g of calcined alumina, 10g of barite, 20g of fluorite, and 16g of limestone. Place the above raw materials in a high-speed mixer and mix them at 2000 rpm for 5 times, each time for 3 seconds, with a 5-minute interval between two mixings to obtain a mixture;

[0092] Step 3, weigh 15.44 g of the mixture obtained in step 4 and place it in a mold, place it on a hot press, set the pressure to 5 MPa, the temperature to 170°C, the hot pressing time to 10 min, release the air once every 50 seconds during hot pressing curing, and release the air once every 100 seconds after 400 seconds, and obtain a semi-finished product after hot pressing curing; place the semi-finished product in an electric hot air drying oven for heat treatment, the procedure is: start from room temperature to 125°C for 20 minutes and then keep warm for 50 minutes; continue to heat up to 170°C for 20 minutes and keep warm for 80 minutes; continue to heat up to 185°C for 10 minutes and keep warm for 35 minutes; heat up to 200°C for another 20 minutes and keep warm for 60 minutes, and finally cool to room temperature with a blast drying oven to obtain a modified carbon fiber reinforced resin-based friction material.

[0093] In order to illustrate the relevant performance of the friction material provided by the present invention, it is described in conjunction with the accompanying drawings.

[0094] from Figure 1 It can be seen that compared with the control example, the wear rate of the carbon fiber reinforced resin-based friction material and the metal counterpart is significantly reduced after the synergistic non-destructive modification of CMC / fluorosilane, showing good friction and wear performance and protection for the metal counterpart.

[0095] from Figure 2 It can be seen that compared with the control example, the surface energy of the carbon fiber reinforced resin-based friction material after CMC / fluorosilane synergistic non-destructive modification is significantly reduced, and is consistent with the law of decreasing wear rate, indicating that the reduction in surface energy improves the friction and wear properties of the material.

[0096] Combine Figure 1 and Figure 2 It can be seen that the introduction of CMC and fluorosilane enhances the bonding ability between carbon fiber and resin matrix and reduces the surface energy of the material without damaging the strength of carbon fiber, thereby reducing the generation of abrasive particles during friction and wear and avoiding the plowing effect of hard abrasive particles on the metal dual surface.

[0097] The present invention describes preferred embodiments and their effects. However, those skilled in the art, once informed of the basic inventive concept, may make additional changes and modifications to these embodiments. Therefore, it is intended that the appended claims be interpreted to include the preferred embodiments as well as all changes and modifications that fall within the scope of the invention.

[0098] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material, characterized in that: The friction material comprises the following components by mass percentage: 10-25% thermosetting resin, 15-35% modified carbon fiber, 40-75% regulator, totaling 100%; The modified carbon fiber is obtained by synergistically grafting CMC and fluorosilane on the carbon fiber; The conditioning agent includes one or more of alumina, kaolin, calcium sulfate whiskers, carbon black, diatomaceous earth, graphite, black rubber powder, sublimated sulfur, nitrile rubber, hematite, barite, and limestone; The modified carbon fiber is prepared according to the following steps: Add CMC powder to deionized water and stir at 60-80°C for 90-120 minutes to obtain CMC solution; Immerse the carbon fiber in the CMC solution and let it stand at 60-80°C for 30-90 minutes to obtain activated carbon fiber; dissolving fluorosilane in acetone to obtain a fluorosilane-acetone solution; The activated carbon fibers are immersed in a fluorosilane-acetone solution, and then ammonia water is added and stirred, and then the solvent is removed to obtain modified carbon fibers; Among them, CMC is carboxymethyl cellulose.

2. The CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material according to claim 1, characterized in that: The thermosetting resin includes one or more of modified phenolic resin, epoxy resin, cyanate resin, bismaleimide resin, and vinyl ester resin.

3. The CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material according to claim 1, characterized in that: The carbon fiber is one or more of polyacrylonitrile-based carbon fiber, asphalt-based carbon fiber, and viscose-based carbon fiber; wherein the carbon fiber has a length of 1-20 microns.

4. The CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material according to claim 1, characterized in that: The fluorosilane includes one or more of 1H,1H,2H,2H-perfluorooctyltrichlorosilane, trifluoropropylmethyl silicone oil, and polydimethylsiloxane.

5. The CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material according to claim 1, characterized in that: The concentration of the fluorosilane-acetone solution is 1-10 g / L.

6. The CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material according to claim 1, characterized in that: The amount of ammonia water added is 1 ml of ammonia water per 20-60 ml of fluorosilane-acetone solution.

7. A method for preparing the CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material according to any one of claims 1 to 6, characterized in that: The following steps are involved: Weigh thermosetting resin, modified carbon fiber and regulator according to proportion, mix and stir to obtain a mixture; The mixture is placed in a mold, and after hot pressing, curing and heat treatment, a CMC / fluorosilane synergistically non-destructive modified carbon fiber reinforced resin-based friction material is obtained.

8. The method for preparing the CMC / fluorosilane synergistic non-destructive modified carbon fiber reinforced resin-based friction material according to claim 7, characterized in that: During the hot pressing curing process, the pressure is set to 5-10 MPa, the temperature is 150-170°C, the hot pressing time is 10-15 min, and the air is released every 50-100 s during the hot pressing curing; During the heat treatment process, Start heating from room temperature to 100-130°C for 20-30 minutes and then keep warm for 40-60 minutes; Continue heating for 20-30 minutes to 160-180°C and keep warm for 70-90 minutes; Continue heating for 5-20 minutes to 185-190°C and keep warm for 30-40 minutes; Then heat it up to 195-200°C for 20-30 min, keep it warm for 50-80 min, and finally cool it to room temperature in a blast drying oven.

9. Use of the CMC / fluorosilane synergistically non-destructive modified carbon fiber reinforced resin-based friction material according to any one of claims 1 to 6 in brakes, clutches or friction transmission devices.

Images