A surface treatment process for motorcycle brake pads that fluoresces green

Abstract

The application discloses a motorcycle brake pad green fluorescent surface treatment process and belongs to the technical field of paints. 2+ The green fluorescent system containing Eu 2+ has high luminous color purity and great fluorescent intensity, can realize clear visual identification of the brake pad in the night, dim light and complex road conditions, realizes uniform fluorescent distribution and good luminous consistency of the coating by loading and dispersing the fluorescent powder by using the expanded pore silicon dioxide, can reduce the quenching of the fluorescent powder by external substances by the space confinement effect of the expanded pore silicon dioxide, and significantly prolongs the effective life of the fluorescent function by accompanying the functional polypropylene modification containing the hindered phenol structure; and the application forms a dense organic protective layer on the surface of the fluorescent hybrid material by PP-g-MAH graft modification and functional polypropylene coating, and significantly improves the thermal stability of the fluorescent filler by isolating oxygen and moisture.

Description

Technical Field

[0001] This invention belongs to the field of coating technology, specifically a surface treatment process for green fluorescentizing motorcycle brake pads. Background Technology

[0002] Fluorescent coatings combine the properties of coatings and fluorescence, and have been widely used in traffic signs, road markings, safety signs, automotive parts, decorations and other fields. Currently, fluorescent coatings are required to have not only higher luminous intensity, but also more luminous wavelengths and better overall performance.

[0003] With the accelerated electrification transformation of the motorcycle transportation industry, the market size of traditional fuel motorcycles and new energy electric motorcycles continues to expand. As a core safety component of vehicles, the braking system is undergoing a comprehensive upgrade in terms of performance and quality requirements. Currently, consumers' demand for brake pads has evolved from a single safety function to a composite demand of "safety performance, visual recognition, and functional integration." When riding at night, the luminous brake pads form a green halo as the wheel rotates, significantly improving the visibility of the vehicle's sides and rear, helping other road users (cars, pedestrians) to spot the motorcycle in time and reducing the risk of nighttime traffic accidents. During repairs, the brake pads can be quickly located, especially in low-light garages or roadside emergency repair scenarios.

[0004] Chinese patent CN119432204A discloses a high-brightness luminescent thermosetting powder coating and its preparation method. In this scheme, fluorescent powder is used as the luminescent material, and glycidyl acrylate modified polycarbonate, hydrogenated bisphenol A epoxy resin and tetraphenol ethylene epoxy resin are used as the main components of the coating. Due to its relatively high transparency and purity, the light emitted by the fluorescent powder can penetrate the coating more easily, thereby enhancing the brightness at night. However, when the fluorescent powder is applied to brake pads, the long-term operation of the brake pads at high temperatures can easily cause the fluorescent material to quench, affecting the luminescent performance. Summary of the Invention

[0005] The purpose of this invention is to provide a green fluorescent surface treatment process for motorcycle brake pads, using a process containing Eu. 2+ The green fluorescent system has high emission color purity and high fluorescence intensity, which can clearly and visually mark brake pads at night, in low light and in complex road conditions. The fluorescent powder is loaded and dispersed by expanded pore silica to ensure uniform fluorescence distribution and good luminescence consistency of the coating. The spatial confinement effect of expanded pore silica can reduce the quenching of fluorescent powder by external substances. In addition, the functionalized polypropylene with hindered phenol structure is modified to significantly extend the effective life of the fluorescent function.

[0006] The objective of this invention can be achieved through the following technical solutions: A surface treatment process for green fluorescentizing motorcycle brake pads includes the following steps: Step 1: Using polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer as a template and 1,3,5-trimethylbenzene as a pore-expanding agent, tetraethyl orthosilicate is hydrolyzed and crystallized to obtain expanded pore silica; by evaporating the solvent at high temperature, green fluorescent powder is uniformly loaded onto the pores and surface of the expanded pore silica to obtain fluorescent mesoporous silica hybrid material.

[0007] Step 2: Dissolve PP-g-MAH in decahydronaphthalene as a solvent, and utilize its maleic anhydride groups to combine with the hydroxyl groups on the surface of the fluorescent mesoporous silica hybrid material to covalently graft polypropylene molecular chains onto the surface of the fluorescent mesoporous silica hybrid material, thereby obtaining the modified fluorescent mesoporous silica hybrid material.

[0008] Step 3: Using decahydronaphthalene as a solvent, the PP segments on the surface of the modified fluorescent mesoporous silica hybrid material are entangled with the functionalized polypropylene molecular chains to form a coating of the modified fluorescent mesoporous silica hybrid material by functionalized polypropylene, thus obtaining an aging-resistant green fluorescent powder.

[0009] Step 4: Spray the aging-resistant green fluorescent coating onto the NGBBP motorcycle / ATV semi-metallic brake pads at a rate of 0.01-0.02 g / cm³. 2 Place them in a vacuum oven at 120-130℃ and dry for 30-40 minutes to complete the green fluorescent surface treatment process for motorcycle brake pads.

[0010] Furthermore, the specific preparation steps of the green fluorescent powder are as follows: SrCO3, La2O3, Eu2O3, (NH4)2HPO4 and SiO2 were placed in an agate mortar and ground for 20-30 min at 20-25℃ and 150-170 r / min to obtain precursor powder. The precursor powder was transferred to a tube furnace and a mixed gas of H2 and Ne with a volume ratio of 1:19 and a total flow rate of 60 mL / min was introduced. The furnace was heated to 800-900℃ and sintered for 2-3 h. After natural cooling to room temperature, the product was washed 2-4 times with deionized water and vacuum dried at 60-70℃ for 1-2 h to obtain green fluorescent powder.

[0011] Furthermore, the mass ratio of SrCO3, La2O3, Eu2O3, (NH4)2HPO4 and SiO2 is 0.5-0.8g: 0.3-0.4g: 0.02-0.04g: 0.5-0.6g: 0.02-0.03g.

[0012] Furthermore, the specific preparation steps for expanded-pore silica are as follows: Polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer, 2 mol / L hydrochloric acid solution, and deionized water were added to a reaction vessel and stirred at 50-60℃ and 400-500 r / min for 20-30 min. Then, 1,3,5-trimethylbenzene was added, and stirring was continued for 2-3 h. Then, tetraethyl orthosilicate was added, and stirring was continued for 24-26 h. The mixture was heated to 90-92℃ for crystallization for 24-26 h, filtered, and the product was washed 2-4 times with deionized water. It was then extracted with ethanol as solvent at 130-140℃ for 24-26 h and vacuum dried at 60-70℃ for 1-2 h to obtain expanded-pore silica.

[0013] Furthermore, the ratio of polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer, hydrochloric acid solution, deionized water, 1,3,5-trimethylbenzene and tetraethyl orthosilicate is 6-8g: 180-200mL: 45-50mL: 3-4g: 12-14g.

[0014] Furthermore, the specific preparation steps of the fluorescent mesoporous silica hybrid material are as follows: Green fluorescent powder and N,N-dimethylformamide were added to a reaction vessel and stirred for 20-30 minutes at 50-60℃ and 400-500 r / min. Then, expanded pore silica and anhydrous ethanol were added, and stirring was continued for 1-2 hours. The mixture was then sonicated at 180-190 W for 1-2 hours, heated to 80-90℃ to evaporate the solvent, and then dried in a vacuum oven at 120-130℃ to constant weight to obtain a fluorescent mesoporous silica hybrid material.

[0015] Furthermore, the ratio of green fluorescent powder, N,N-dimethylformamide, expanded silica and anhydrous ethanol is 2-3g: 50-90mL: 4-5g: 80-90mL.

[0016] Furthermore, the specific preparation steps of the modified fluorescent mesoporous silica hybrid material are as follows: PP-g-MAH and decahydronaphthalene were added to a reaction vessel and stirred for 20-30 min at 150-160℃ and 400-500 r / min. Then, fluorescent mesoporous silica hybrid material was added and the reaction was continued for 1-2 h. The mixture was filtered and the product was washed 2-4 times with deionized water and anhydrous ethanol, respectively. The product was then dried under vacuum at 60-70℃ for 1-2 h to obtain the modified fluorescent mesoporous silica hybrid material.

[0017] Furthermore, the ratio of PP-g-MAH, decahydronaphthalene, and fluorescent mesoporous silica hybrid material is 10-12g: 100-130mL: 1-2g.

[0018] Furthermore, the specific preparation steps of the aging-resistant green fluorescent powder are as follows: Functionalized polypropylene and decahydronaphthalene were added to a polytetrafluoroethylene reactor and stirred for 20-30 min at 140-150℃ and 400-500 r / min. Then, modified fluorescent mesoporous silica hybrid material was added, and the mixture was cooled to 80-90℃ and sonicated at 180-190 W for 20-30 min. After naturally cooling to room temperature, the mixture was filtered, and the product was washed 2-4 times with deionized water and anhydrous ethanol, respectively. The product was then vacuum dried at 60-70℃ for 1-2 h to obtain an aging-resistant green fluorescent powder.

[0019] Furthermore, the ratio of functionalized polypropylene, decahydronaphthalene, and modified fluorescent mesoporous silica hybrid material is 0.9-1g: 50-60mL: 0.4-0.6g.

[0020] Furthermore, the specific preparation steps of the aging-resistant green fluorescent coating are as follows: Nitrile latex, sodium hexametaphosphate, sodium carboxymethyl cellulose, sulfur, accelerator M, zinc oxide, light magnesium oxide, and aging-resistant green fluorescent powder are stirred and mixed, and ground at 20-25℃ and 150-170r / min for 1-2 hours. Then deionized water is added and stirred for 20-30 minutes to form an aging-resistant green fluorescent coating.

[0021] Furthermore, the ratio of nitrile latex, sodium hexametaphosphate, sodium carboxymethyl cellulose, sulfur, accelerator M, zinc oxide, light magnesium oxide, aging-resistant green fluorescent powder, and deionized water is 200-220g: 1-2g: 2-3g: 5-6g: 0.5-0.8g: 1-2g: 100-110g: 8-10g: 200-220g.

[0022] The beneficial effects of this invention are: 1. This invention uses Eu-containing... 2+ The green fluorescent system has high emission color purity and high fluorescence intensity, which can clearly and visually mark brake pads at night, in low light and in complex road conditions. The fluorescent powder is loaded and dispersed by expanded pore silica to ensure uniform fluorescence distribution and good luminescence consistency of the coating. The spatial confinement effect of expanded pore silica can reduce the quenching of fluorescent powder by external substances. In addition, the functionalized polypropylene with hindered phenol structure is modified to significantly extend the effective life of the fluorescent function.

[0023] 2. This invention forms a dense organic protective layer on the surface of fluorescent hybrid materials by grafting and modifying PP-g-MAH and coating with functionalized polypropylene. This isolates oxygen and moisture, significantly improving the thermal stability and weather resistance of the fluorescent filler. The functionalized polypropylene itself contains hindered phenolic structures, which have excellent aging resistance. Combined with the nitrile rubber matrix, the overall fluorescent coating can adapt to the temperature rise environment during brake pad operation, and will not fade or fail after long-term use.

[0024] 3. This invention utilizes PP-g-MAH to chemically modify fluorescent mesoporous silica hybrid materials. Maleic anhydride groups form chemical bonds with hydroxyl groups on the silica surface, and polypropylene segments are grafted onto the filler surface. This solves the problems of large polarity differences and weak interfacial bonding between inorganic fluorescent fillers and organic polypropylene and nitrile rubber. The modified fluorescent mesoporous silica hybrid material has significantly improved compatibility with the rubber matrix, is uniformly dispersed in coatings, and exhibits no obvious phase separation or particle agglomeration, resulting in a dense internal structure of the coating. Detailed Implementation

[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1: A surface treatment process for green fluorescentizing motorcycle brake pads, comprising the following steps: S1: 0.5g SrCO3, 0.3g La2O3, 0.02g Eu2O3, 0.5g (NH4)2HPO4 and 0.02g SiO2 were placed in an agate mortar and ground for 20 min at 20℃ and 150 r / min to obtain precursor powder. The precursor powder was transferred to a tube furnace and a mixed gas of H2 and Ne with a volume ratio of 1:19 and a total flow rate of 60 mL / min was introduced. The furnace was heated to 800℃ and sintered for 2 h. After natural cooling to room temperature, the product was washed twice with deionized water and dried under vacuum at 60℃ for 1 h to obtain green fluorescent powder with an average particle size of 10 nm.

[0027] S2: Add 6g of polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer, 180mL of 2mol / L hydrochloric acid solution, and 45mL of deionized water to a reaction vessel. Stir for 20min at 50℃ and 400r / min. Then add 3g of 1,3,5-trimethylbenzene and continue stirring for 2h. Then add 12g of tetraethyl orthosilicate and continue stirring for 24h. Heat to 90℃ for crystallization for 24h, filter, wash the product twice with deionized water, extract with ethanol as solvent at 130℃ for 24h, and vacuum dry at 60℃ for 1h to obtain expanded-pore silica.

[0028] S3: Add 2g of green fluorescent powder and 50mL of N,N-dimethylformamide to a reaction vessel, stir for 20min at 50℃ and 400r / min, then add 4g of expanded pore silica and 80mL of anhydrous ethanol, continue stirring for 1h, sonicate at 180w for 1h, heat to 80℃ to evaporate the solvent, and then dry in a vacuum oven at 120℃ to constant weight to obtain fluorescent mesoporous silica hybrid material.

[0029] S4: Add 10g PP-g-MAH and 100mL decahydronaphthalene to the reactor and stir for 20min at 150℃ and 400r / min. Then add 1g of fluorescent mesoporous silica hybrid material and continue the reaction for 1h. Filter the mixture and wash the product twice with deionized water and anhydrous ethanol, respectively. Dry the product under vacuum at 60℃ for 1h to obtain the modified fluorescent mesoporous silica hybrid material.

[0030] S5: Add 0.9g of functionalized polypropylene and 50mL of decahydronaphthalene to a polytetrafluoroethylene reactor, stir for 20min at 140℃ and 400r / min, then add 0.4g of modified fluorescent mesoporous silica hybrid material, then cool to 80℃, sonicate at 180w for 20min, cool naturally to room temperature, filter, wash the product twice with deionized water and anhydrous ethanol respectively, and vacuum dry at 60℃ for 1h to obtain aging-resistant green fluorescent powder.

[0031] S6: Mix 200g nitrile latex, 1g sodium hexametaphosphate, 2g sodium carboxymethyl cellulose, 5g sulfur, 0.5g accelerator M, 1g zinc oxide, 100g light magnesium oxide, and 8g aging-resistant green fluorescent powder. Grind at 20℃ and 150r / min for 1 hour. Then add 200g deionized water and mix for 20 minutes to form an aging-resistant green fluorescent coating. Spray the aging-resistant green fluorescent coating onto the semi-metallic brake pads of NGBBP motorcycles / ATVs at a coating amount of 0.01g / cm². 2 The surface treatment process for green fluorescentizing of motorcycle brake pads is completed by placing them in a vacuum oven at 120°C for 30 minutes.

[0032] Example 2: A surface treatment process for green fluorescentizing motorcycle brake pads, comprising the following steps: 0.7 g SrCO3, 0.35 g La2O3, 0.03 g Eu2O3, 0.55 g (NH4)2HPO4 and 0.025 g SiO2 were placed in an agate mortar and ground for 25 min at 23 °C and 160 r / min to obtain precursor powder. The precursor powder was transferred to a tube furnace and a mixed gas of H2 and Ne with a volume ratio of 1:19 and a total flow rate of 60 mL / min was introduced. The furnace was heated to 850 °C and sintered for 2.5 h. After natural cooling to room temperature, the product was washed three times with deionized water and dried under vacuum at 65 °C for 1.2 h to obtain green fluorescent powder with an average particle size of 10 nm.

[0033] S2: 7g of polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer, 190mL of 2mol / L hydrochloric acid solution, and 47.5mL of deionized water were added to a reaction vessel and stirred at 55℃ and 450r / min for 25min. Then, 3.5g of 1,3,5-trimethylbenzene was added, and stirring was continued for 2.5h. Then, 13g of tetraethyl orthosilicate was added, and stirring was continued for 25h. The mixture was heated to 91℃ for crystallization for 25h, filtered, and the product was washed three times with deionized water. It was then extracted with ethanol as solvent at 135℃ for 25h and dried under vacuum at 65℃ for 1.5h to obtain expanded-pore silica.

[0034] S3: Add 2.5g of green fluorescent powder and 70mL of N,N-dimethylformamide to a reaction vessel, stir for 25min at 55℃ and 450r / min, then add 4.5g of expanded pore silica and 85mL of anhydrous ethanol, continue stirring for 1.5h, sonicate at 185w for 1.5h, heat to 85℃ to evaporate the solvent, and then dry in a vacuum oven at 125℃ to constant weight to obtain fluorescent mesoporous silica hybrid material.

[0035] S4: Add 11g PP-g-MAH and 115mL decahydronaphthalene to the reactor and stir for 25min at 155℃ and 450r / min. Then add 1.5g fluorescent mesoporous silica hybrid material and continue the reaction for 1.5h. Filter the mixture and wash the product three times with deionized water and anhydrous ethanol, respectively. Dry the product under vacuum at 65℃ for 1.5h to obtain the modified fluorescent mesoporous silica hybrid material.

[0036] S5: Add 0.95g of functionalized polypropylene and 55mL of decahydronaphthalene to a polytetrafluoroethylene reactor, stir for 25min at 145℃ and 450r / min, then add 0.45g of modified fluorescent mesoporous silica hybrid material, then cool to 85℃, sonicate at 185w for 25min, cool naturally to room temperature, filter, wash the product three times with deionized water and anhydrous ethanol respectively, and vacuum dry at 65℃ for 1.5h to obtain aging-resistant green fluorescent powder.

[0037] S6: Mix 210g nitrile latex, 1.5g sodium hexametaphosphate, 2.5g sodium carboxymethyl cellulose, 5.5g sulfur, 0.65g accelerator M, 1.5g zinc oxide, 105g light magnesium oxide, and 9g aging-resistant green fluorescent powder. Grind at 22.5℃ and 160r / min for 1.5h. Then add 210g deionized water and mix for 25min to form an aging-resistant green fluorescent coating. Spray the aging-resistant green fluorescent coating onto the semi-metallic brake pads of NGBBP motorcycles / ATVs at a coating amount of 0.015g / cm². 2 The surface treatment process for green fluorescentizing of motorcycle brake pads is completed by placing them in a vacuum oven at 125°C for 35 minutes.

[0038] Example 3: A surface treatment process for green fluorescentizing motorcycle brake pads, comprising the following steps: S1: 0.8g SrCO3, 0.4g La2O3, 0.04g Eu2O3, 0.6g (NH4)2HPO4 and 0.03g SiO2 were placed in an agate mortar and ground for 30 min at 25℃ and 170 r / min to obtain precursor powder. The precursor powder was transferred to a tube furnace and a mixed gas of H2 and Ne with a volume ratio of 1:19 and a total flow rate of 60 mL / min was introduced. The furnace was heated to 900℃ and sintered for 3 h. After natural cooling to room temperature, the product was washed 4 times with deionized water and vacuum dried at 70℃ for 2 h to obtain green fluorescent powder with an average particle size of 10 nm.

[0039] S2: Add 8g of polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer, 200mL of 2mol / L hydrochloric acid solution, and 50mL of deionized water to a reaction vessel. Stir for 30min at 60℃ and 500r / min. Then add 4g of 1,3,5-trimethylbenzene and continue stirring for 3h. Then add 14g of tetraethyl orthosilicate and continue stirring for 26h. Heat to 92℃ for crystallization for 26h, filter, wash the product 4 times with deionized water, extract with ethanol as solvent at 140℃ for 26h, and vacuum dry at 70℃ for 2h to obtain expanded-pore silica.

[0040] S3: Add 3g of green fluorescent powder and 90mL of N,N-dimethylformamide to a reaction vessel, stir for 30min at 60℃ and 500r / min, then add 5g of expanded pore silica and 90mL of anhydrous ethanol, continue stirring for 2h, sonicate at 190w for 2h, heat to 90℃ to evaporate the solvent, and then dry in a vacuum oven at 130℃ to constant weight to obtain fluorescent mesoporous silica hybrid material.

[0041] S4: Add 12g PP-g-MAH and 130mL decahydronaphthalene to the reactor and stir for 30min at 160℃ and 500r / min. Then add 2g of fluorescent mesoporous silica hybrid material and continue the reaction for 2h. Filter the mixture and wash the product 4 times with deionized water and anhydrous ethanol respectively. Dry the product under vacuum at 70℃ for 2h to obtain the modified fluorescent mesoporous silica hybrid material.

[0042] S5: Add 1g of functionalized polypropylene and 60mL of decahydronaphthalene to a polytetrafluoroethylene reactor, stir for 30min at 150℃ and 500r / min, then add 0.5g of modified fluorescent mesoporous silica hybrid material, then cool to 90℃, sonicate at 190w for 30min, cool naturally to room temperature, filter, wash the product 4 times with deionized water and anhydrous ethanol respectively, and vacuum dry at 70℃ for 2h to obtain aging-resistant green fluorescent powder.

[0043] S6: Mix 220g nitrile latex, 2g sodium hexametaphosphate, 3g sodium carboxymethyl cellulose, 6g sulfur, 0.8g accelerator M, 2g zinc oxide, 110g light magnesium oxide, and 10g aging-resistant green fluorescent powder. Grind at 25℃ and 170r / min for 2 hours. Then add 220g deionized water and mix for 30 minutes to form an aging-resistant green fluorescent coating. Spray the aging-resistant green fluorescent coating onto the semi-metallic brake pads of NGBBP motorcycles / ATVs at a coating amount of 0.02g / cm². 2 The surface treatment process for green fluorescentizing of motorcycle brake pads is completed by placing them in a vacuum oven at 130°C for 40 minutes.

[0044] Comparative Example 1: Based on Example 3, the pore-expanding silica in step S3 was replaced with commercially available silica, while the other steps remained unchanged, to prepare an aging-resistant green fluorescent coating and complete the green fluorescent surface treatment process for motorcycle brake pads.

[0045] Comparative Example 2: Based on Example 3, the modified fluorescent mesoporous silica hybrid material in step S5 was replaced with the fluorescent mesoporous silica hybrid material prepared in step S3, while the other steps remained unchanged, and an aging-resistant green fluorescent coating was prepared, thus completing the green fluorescent surface treatment process for motorcycle brake pads.

[0046] Comparative Example 3: Based on Example 3, the aging-resistant green fluorescent powder in step S6 was replaced with the modified fluorescent mesoporous silica hybrid material prepared in step S4, while the other steps remained unchanged, to prepare an aging-resistant green fluorescent coating and complete the green fluorescent surface treatment process for motorcycle brake pads.

[0047] In the examples and comparative examples: 1,3,5-Trimethylbenzene was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No.: 108-67-8, molecular weight: 120.19.

[0048] PP-g-MAH was purchased from Dongguan Shangyi Plastics Co., Ltd., model: AT2747, density: 0.910 g / cm³. 3 .

[0049] Accelerator M was purchased from Greenlink (Jining) Chemical Technology Co., Ltd., CAS No.: 149-30-4.

[0050] Zinc oxide was purchased from Henan Juteng Chemical Products Co., Ltd., CAS No. 1314-13-2, density: 5.6 g / cm³. 3 .

[0051] Light magnesium oxide was purchased from Changsha Rongqing Chemical Products Co., Ltd., CAS No.: 1309-48-4.

[0052] The polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer (polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer) was purchased from Henan Weitixi Chemical Technology Co., Ltd., CAS No.: 106392-12-5.

[0053] The functionalized polypropylene was purchased from Polymics, model number HP200.

[0054] The decahydronaphthalene was purchased from Shandong Yuxuan Chemical Products Co., Ltd., CAS No.: 91-17-8.

[0055] The nitrile latex was purchased from Shandong Wang's Brothers Rubber & Plastics Technology Co., Ltd., model: LXNBR-827.

[0056] The NGBBP motorcycle / ATV semi-metallic brake pads were purchased from Anhui Xiangchi Vehicle Industry Co., Ltd.

[0057] Performance tests were conducted on Examples 1-3 and Comparative Examples 1-3. The tensile strength of the aging-resistant green fluorescent coating was tested according to GB / T 528-2009, and the tensile strength was tested again after the coating was placed at 300℃ and 60% relative humidity for 50 hours. The heat resistance of the aging-resistant green fluorescent coating was tested according to GB / T 1735-2009, and the salt spray resistance was tested according to GB / T 1771-2007. The results are shown in Table 1. Table 1 As shown in Table 1, ordinary silica lacks ordered mesoporous and expanded pore structures, making it unable to load and spatially confine fluorescent powder. The fluorescent powder is prone to agglomeration, resulting in uneven fluorescence distribution and decreased brightness in the coating. Furthermore, the fluorescent powder is more easily quenched by the external environment, significantly shortening the fluorescence lifetime. Ordinary silica has a small specific surface area, weak bonding force with the rubber matrix, low internal density of the coating, low tensile strength, and substandard heat resistance and salt spray resistance. The loose coating structure cannot meet the long-term operating requirements of brake pads.

[0058] In Comparative Example 2, the PP-g-MAH chemical grafting process was not performed. The fluorescent mesoporous silica hybrid material was still a highly polar inorganic material, which had a huge difference in polarity from the non-polar functionalized polypropylene. This resulted in severe phase separation and filler agglomeration problems. There was no chemical bonding or molecular chain entanglement at the inorganic-organic interface, resulting in extremely poor bonding force, reduced tensile strength, and an inability to form a continuous and dense polypropylene protective layer. The phosphor was easily quenched and failed when directly exposed to a thermal environment. The coating cracked and powdered severely at high temperatures, and blistered and peeled off over a large area under salt spray conditions.

[0059] Comparative Example 3 only has PP-g-MAH surface grafting, without a complete functional polypropylene coating layer, which cannot effectively isolate oxygen and moisture, and lacks the synergistic protection of hindered phenolic structure. It has poor thermal stability, the coating protective layer is not dense, the tensile strength is low, and it softens and peels at high temperatures. It cannot adapt to the braking temperature rise conditions of brake pads. The coating structure is not complete enough, and long-term use is prone to coating peeling and rapid fluorescence decay.

[0060] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. A surface treatment process for green fluorescentizing motorcycle brake pads, characterized in that, Includes the following steps: Nitrile latex, sodium hexametaphosphate, sodium carboxymethyl cellulose, sulfur, accelerator M, zinc oxide, light magnesium oxide, and aging-resistant green fluorescent powder are mixed to form an aging-resistant green fluorescent coating. This coating is then sprayed onto the semi-metallic brake pads of NGBBP motorcycles and ATVs at a rate of 0.01-0.02 g / cm³. 2 After drying, the green fluorescent surface treatment process for motorcycle brake pads is completed. The aging-resistant green fluorescent powder is prepared by the following steps: Using decahydronaphthalene as a solvent, the PP segments on the surface of the modified fluorescent mesoporous silica hybrid material are entangled with the functionalized polypropylene molecular chains to form a coating of the modified fluorescent mesoporous silica hybrid material by functionalized polypropylene, thus obtaining an aging-resistant green fluorescent powder.

2. The green fluorescent surface treatment process for motorcycle brake pads according to claim 1, characterized in that, The ratio of the following components to be used is 200-220g: 1-2g: 2-3g: 5-6g: 0.5-0.8g: 1-2g: 100-110g: 8-10g: 200-220g.

3. The green fluorescent surface treatment process for motorcycle brake pads according to claim 1, characterized in that, The specific preparation steps of the green fluorescent powder are as follows: SrCO3, La2O3, Eu2O3, (NH4)2HPO4 and SiO2 were placed in an agate mortar and ground for 20-30 min at 20-25℃ and 150-170 r / min to obtain precursor powder. The precursor powder was transferred to a tube furnace and a mixed gas of H2 and Ne with a volume ratio of 1:19 and a total flow rate of 60 mL / min was introduced. The furnace was heated to 800-900℃ and sintered for 2-3 h. After natural cooling to room temperature, the product was washed 2-4 times with deionized water and vacuum dried at 60-70℃ for 1-2 h to obtain green fluorescent powder.

4. The green fluorescent surface treatment process for motorcycle brake pads according to claim 3, characterized in that, The mass ratio of SrCO3, La2O3, Eu2O3, (NH4)2HPO4 and SiO2 is 0.5-0.8g: 0.3-0.4g: 0.02-0.04g: 0.5-0.6g: 0.02-0.03g.

5. The green fluorescent surface treatment process for motorcycle brake pads according to claim 1, characterized in that, The specific preparation steps of the modified fluorescent mesoporous silica hybrid material are as follows: PP-g-MAH and decahydronaphthalene were added to a reaction vessel and stirred for 20-30 min at 150-160℃ and 400-500 r / min. Then, fluorescent mesoporous silica hybrid material was added and the reaction was continued for 1-2 h. The mixture was filtered and the product was washed 2-4 times with deionized water and anhydrous ethanol, respectively. The product was then dried under vacuum at 60-70℃ for 1-2 h to obtain the modified fluorescent mesoporous silica hybrid material. The ratio of the PP-g-MAH, decahydronaphthalene and fluorescent mesoporous silica hybrid material is 10-12g: 100-130mL: 1-2g.

6. The green fluorescent surface treatment process for motorcycle brake pads according to claim 5, characterized in that, The specific preparation steps of the fluorescent mesoporous silica hybrid material are as follows: Green fluorescent powder and N,N-dimethylformamide were added to a reaction vessel and stirred for 20-30 min at 50-60℃ and 400-500 r / min. Then, expanded pore silica and anhydrous ethanol were added, and stirring was continued for 1-2 h. The mixture was sonicated at 180-190 W for 1-2 h, heated to 80-90℃ to evaporate the solvent, and then dried in a vacuum oven at 120-130℃ to constant weight to obtain fluorescent mesoporous silica hybrid material. The ratio of the green fluorescent powder, N,N-dimethylformamide, expanded silica, and anhydrous ethanol is 2-3g: 50-90mL: 4-5g: 80-90mL.

7. The green fluorescent surface treatment process for motorcycle brake pads according to claim 6, characterized in that, The specific preparation steps for the expanded-pore silica are as follows: Polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer, 2 mol / L hydrochloric acid solution, and deionized water were added to a reaction vessel and stirred at 50-60℃ and 400-500 r / min for 20-30 min. Then, 1,3,5-trimethylbenzene was added, and stirring was continued for 2-3 h. Then, tetraethyl orthosilicate was added, and stirring was continued for 24-26 h. The mixture was heated to 90-92℃ for crystallization for 24-26 h, filtered, and the product was washed 2-4 times with deionized water. It was then extracted with ethanol as solvent at 130-140℃ for 24-26 h and vacuum dried at 60-70℃ for 1-2 h to obtain expanded-pore silica.

8. The green fluorescent surface treatment process for motorcycle brake pads according to claim 7, characterized in that, The ratio of the polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer, hydrochloric acid solution, deionized water, 1,3,5-trimethylbenzene and tetraethyl orthosilicate is 6-8g: 180-200mL: 45-50mL: 3-4g: 12-14g.

9. The green fluorescent surface treatment process for motorcycle brake pads according to claim 1, characterized in that, The specific preparation steps of the aging-resistant green fluorescent powder are as follows: Functionalized polypropylene and decahydronaphthalene were added to a polytetrafluoroethylene reactor and stirred for 20-30 min at 140-150℃ and 400-500 r / min. Then, modified fluorescent mesoporous silica hybrid material was added, and the mixture was cooled to 80-90℃ and sonicated at 180-190 W for 20-30 min. After naturally cooling to room temperature, the mixture was filtered, and the product was washed 2-4 times with deionized water and anhydrous ethanol, respectively. The product was then vacuum dried at 60-70℃ for 1-2 h to obtain an aging-resistant green fluorescent powder.

10. The green fluorescent surface treatment process for motorcycle brake pads according to claim 9, characterized in that, The ratio of the functionalized polypropylene, decahydronaphthalene, and modified fluorescent mesoporous silica hybrid material is 0.9-1g: 50-60mL: 0.4-0.6g.

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