A composite material for a bearing cage and a method for producing the same

Abstract

The application discloses a kind of bearing cage composite material and preparation method thereof, belong to high polymer composite material technical field, including the following mass percentage of components: thermoplastic polymer 10-30%, modified montmorillonite 5-10%, modified short glass fiber 10-20%, lubricant 5-15%, compatibilizer 3-5%, the balance of nylon particle.The application under the action of compatibilizer, so that the complementary thermoplastic polymer and nylon 46 form the plastic alloy with excellent comprehensive performance, further toughening modification is carried out to the composite material using modified lipophilic inorganic material glass fiber and montmorillonite, in addition, by polytetrafluoroethylene superfine powder, the composite material is endowed with good lubricity, under the action of compatibilizer, under the action of heating melting and shearing force, further physical and chemical action occurs between the composite material, obtain high polymer composite material for bearing cage with low water absorption, high mechanical strength, good heat resistance, good lubricating property.

Description

Technical Field

[0001] This invention relates to the field of polymer composite materials technology, specifically a high-strength, high-wear-resistant composite material for bearing cages and its preparation method. Background Technology

[0002] Bearings are critical components ensuring the operation of mechanical equipment, directly determining its reliability, efficiency, and lifespan. The cage is one of the essential parts of a rolling bearing. During operation, the cage is subjected to mechanical stresses such as friction and centrifugal force, and also withstands the corrosive effects of certain chemical media. Therefore, bearing cages must possess not only sufficient strength but also properties such as high-temperature resistance, wear resistance, impact resistance, and corrosion resistance. Traditional rolling bearings primarily use metal stamped cages. However, with the rapid development of polymer composite materials, these materials are widely used in the bearing industry due to their advantages such as light weight, low operating noise, and good lubrication performance.

[0003] Nylon possesses a range of excellent properties, including high strength, good heat resistance, self-lubrication, and good chemical resistance. Moreover, the raw materials are readily available and reasonably priced, making it an ideal wear-resistant and self-lubricating material with increasingly widespread applications. However, using nylon materials for bearing cages still presents some shortcomings. First, due to the presence of polar amide groups, nylon has a high water absorption rate, leading to a decrease in mechanical properties and dimensional stability after water absorption. Second, the thermal properties of nylon vary greatly; with temperature changes, the mechanical properties of nylon materials change significantly. Thermal deformation of the nylon cage can cause phenomena such as "bearing seizure" and cage burning deformation, resulting in bearing failure. Furthermore, special working conditions in high-tech fields require improved friction and wear resistance and mechanical properties of nylon materials, enhancing their wear resistance and service life. Therefore, selecting suitable nylon materials, modifying them to reduce water absorption, and improving friction and wear resistance and mechanical properties to prepare a high-strength, high-wear-resistant nylon composite material suitable for bearing cages is of great significance. Summary of the Invention

[0004] The purpose of this invention is to provide a high-strength, high-wear-resistant composite material for bearing cages and its preparation method. The composite material uses high-strength nylon as the matrix material, which is modified to improve the performance degradation of nylon material during use due to its high water absorption rate. At the same time, the thermal and mechanical properties are modified.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The first objective of this invention is to provide a composite material for bearing cages, comprising the following components by weight percentage: 10-30% thermoplastic polymer, 5-10% modified montmorillonite, 10-20% modified chopped glass fiber, 5-15% lubricant, 3-5% compatibilizer, and the balance being nylon particles.

[0007] Preferably, the thermoplastic polymer material is one or more of polyphenylene sulfide, polyester, and polyphenylene ether. Polyphenylene sulfide, polyester, and polyphenylene ether have similar melting points and viscosity indices to nylon 46. Under the action of compatibilizer, they can form plastic alloys with nylon 46, reduce the water absorption of nylon 46, improve mechanical strength, and optimize processing performance.

[0008] Preferably, the polyphenylene sulfide is a special engineering plastic with excellent comprehensive performance, featuring flame retardancy, balanced mechanical properties, corrosion resistance, high temperature resistance, good adhesion, and low water absorption.

[0009] Preferably, the polyphenylene ether is an engineering plastic with excellent overall performance, including low water absorption, excellent heat resistance, and dimensional stability.

[0010] Preferably, the polyester is polyethylene terephthalate (PET), a crystalline thermoplastic saturated polyester with excellent mechanical properties, chemical stability and good processing performance, low water absorption rate and minimal change in material strength after water absorption.

[0011] Preferably, the modified montmorillonite is an organo-montmorillonite modified from sodium-based montmorillonite using tri-n-butyltetradecylphosphine chloride. The sodium-based montmorillonite has a purity >98% and an average particle size of 16-22 μm.

[0012] Preferably, the modified chopped glass fiber is obtained by further hydrophobic modification of chopped glass fiber modified with a silane coupling agent using perfluorodecyltriethoxysilane, resulting in oleophilic chopped glass fiber. The oleophilic chopped glass fiber powder has good compatibility with the polymer and can improve the mechanical strength of the polymer material. The silane coupling agent-modified chopped glass fiber used in this invention has a single filament diameter of 11 μm and a particle size of 100 mesh.

[0013] Preferably, the lubricant is polytetrafluoroethylene ultrafine powder with an average particle size of 5 μm and a specific surface area of ​​10 μm. 2 Polytetrafluoroethylene (PTFE) possesses excellent heat resistance, weather resistance, cold resistance, low friction, and chemical stability. When added to composite materials as a solid lubricant, it can reduce the coefficient of friction and improve the wear resistance of the composite material. Compared to solid lubricants such as graphite and molybdenum disulfide, PTFE has a lower coefficient of friction, and as an organic material, PTFE polymer alloys exhibit better compatibility with nylon 46.

[0014] Preferably, the compatibilizer is styrene-butadiene-styrene-grafted maleic anhydride (SEBS-g-MAH). SEBS-g-MAH is a reactive compatibilizer that can improve the compatibility between nylon 46 and other materials.

[0015] Preferably, the nylon particles are nylon 46 particles. Nylon 46 is a high-temperature resistant nylon whose molecular chain contains a large number of amide groups and has high symmetry. Therefore, nylon 46 has high crystallinity, high melting point, high rigidity, high heat resistance, and fatigue resistance. Compared with other nylon materials, such as nylon 66, nylon 6, nylon 1010, and nylon 12, nylon 46 has better heat resistance and higher mechanical strength. Nylon 46 can maintain good mechanical properties for a long time at a temperature of 230°C, and has excellent rigidity, longer fatigue resistance, and excellent wear resistance at high temperatures.

[0016] The second objective of this invention is to provide a method for preparing a composite material for bearing cages, comprising the following steps:

[0017] Step S1: Sodium-based montmorillonite (cation exchange capacity (CEC) of 120 meq / 100g) was added to distilled water to prepare a 10wt% solution. After stirring and reacting in a constant temperature water bath at 75°C for 4 hours, 96 meq / 100g of a 10wt% aqueous solution prepared from tri-n-butyltetradecylphosphine chloride was added dropwise. The reaction was continued in a constant temperature water bath at 75°C for 6 hours. The mixture was filtered, washed with anhydrous ethanol and filtered three times, then washed with distilled water three times and filtered again. The modified organomontmorillonite was dried in a vacuum drying oven at 110°C for 24 hours and then ground and passed through a 200-mesh sieve to obtain organomodified montmorillonite powder.

[0018] Step S2: The silane coupling agent-modified chopped glass fibers were added to anhydrous ethanol to prepare a 20 wt% dispersion. After uniform dispersion, perfluorodecyltriethoxysilane was added, with a mass ratio of perfluorodecyltriethoxysilane to the silane coupling agent-modified chopped glass fibers of 1:4. The mixture was heated and stirred in a 75°C water bath for 3 hours, filtered, and washed with anhydrous ethanol, repeating the filtration process several times. The resulting hydrophobically modified chopped glass fiber powder was dried in a vacuum drying oven at 60°C for 8-10 hours to finally obtain modified chopped glass fibers.

[0019] Step S3: Place the Nylon 46 particles in an 80°C drying oven and dry for 12 hours to remove moisture.

[0020] Step S4: Weigh the thermoplastic polymer, nylon 46, organic modified montmorillonite, lubricant, and compatibilizer according to the proportions, and stir them in a high-speed mixer at a speed of 50~60 rpm for 10~30 minutes until they are evenly mixed to obtain the raw material mixture.

[0021] Step S5: Add the uniformly mixed raw materials and modified chopped glass fibers to a twin-screw extruder for melt blending and extrusion granulation. The chopped glass fibers are added from the side feed port. The extrusion temperature is 290-310℃, the screw speed is 220-250r / min, and the feeding speed is 30kg / h to obtain composite material particles.

[0022] Step S6: Dry the prepared composite material particles in a vacuum drying oven at 120°C for 12 hours.

[0023] Step S7: The dried composite material particles are injection molded using an injection molding machine at an injection temperature of 290-310℃.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] First, regarding the composition of the composite material:

[0026] First, this invention selects nylon 46 as the matrix material for the composite material. Nylon 46 possesses high crystallinity, high melting point, high rigidity, high heat resistance, and fatigue resistance due to its symmetrical molecular structure and the presence of numerous amide bonds in its molecular chains. Nylon 46 exhibits good heat resistance, making it suitable for applications under high temperature, high speed, and high torque conditions. It demonstrates high rigidity and good wear resistance at temperatures above 200°C (and short-term peak temperatures up to 250°C). Therefore, selecting nylon 46 as the matrix material for the composite material used in bearing cage applications results in a composite material with high temperature resistance, wear resistance, oil resistance, fatigue resistance, and good lubricity.

[0027] Secondly, this invention selects one of polyphenylene sulfide, polyphenylene ether, and polyester to prepare a plastic alloy with complementary properties with nylon 46. Polyphenylene sulfide, polyphenylene ether, and polyester are all engineering plastics with excellent comprehensive properties, such as good corrosion resistance, high temperature resistance, and low moisture absorption. At the same time, these three polymers have similar melting points to nylon 46, and can easily be blended to obtain polymer composite materials with excellent comprehensive properties.

[0028] Third, this invention selects styrene-butadiene-styrene-grafted maleic anhydride (SEBS-g-MAH) as a compatibilizer. SEBS-g-MAH is a commonly used reactive compatibilizer. During melt blending, the maleic anhydride active groups on SEBS-g-MAH can react with the functional groups on the nylon 46 molecular chain to generate block or graft copolymers, thereby playing a compatibilizing role and improving the compatibility of nylon 46 with other materials.

[0029] Fourth, this invention uses montmorillonite to modify the composite material. First, sodium-based montmorillonite is ion-exchange modified with a cationic quaternary phosphine salt (tri-n-butyltetradecylphosphine chloride) with a high thermal decomposition temperature, changing its surface from hydrophilic to oleophilic. This reduces the surface energy of the montmorillonite and expands the interlayer space. The modified organo-montmorillonite is then melt-blended with polymers such as nylon 46. Under the action of heat and mechanical shear force, the polymer molecular chains can insert into the lamellar spaces of the montmorillonite and occupy the interlayer space, further expanding the interlayer spacing. This promotes partial or complete exfoliation of the montmorillonite lamellar structure, forming a nanosheet structure that is uniformly distributed in the polymer matrix, forming a polymer-based nanocomposite material. The polymer and montmorillonite lamellars can interact at the interface, resulting in excellent mechanical properties, thermal stability, and barrier properties. Even a small amount of montmorillonite can effectively improve the mechanical strength, thermal stability, and dimensional stability of the polymer composite material.

[0030] Fifth, this invention selects hydrophobically modified oleophilic short-cut glass fibers as reinforcing materials. Oleophilic short-cut glass fibers have better dispersion uniformity in the polymer matrix. At the same time, under the synergistic effect of compatibilizers, there is a stronger interfacial interaction between glass fibers and polymers, which improves the bonding strength inside the material and thus improves the mechanical strength of the composite material.

[0031] Sixth, this invention uses ultrafine polytetrafluoroethylene (PTFE) powder as a lubricant to improve the lubrication performance of the composite material and reduce its coefficient of friction. During the grinding process between the composite material and the metal surface, PTFE can work synergistically with montmorillonite nanosheets and other polymers to form a dense lubrication transfer film on the surface of the metal surface, giving the composite material excellent self-lubricating properties.

[0032] In summary, this invention, under the action of a compatibilizer, enables complementary thermoplastic polymers and nylon 46 to form a plastic alloy with excellent comprehensive performance. Modified oleophilic inorganic materials, glass fiber and montmorillonite, are used to further reinforce and toughen the composite material. Additionally, ultrafine polytetrafluoroethylene powder imparts good lubricity to the composite material. Together with the compatibilizer, under the action of heating, melting, and shear force, further physicochemical reactions occur between the composite materials, resulting in a polymer composite material with low water absorption, high mechanical strength, good heat resistance, and good lubrication performance, suitable for use in bearing cages.

[0033] Secondly, regarding the preparation methods of composite materials:

[0034] This invention employs a simple ion-exchange intercalation method to organically modify montmorillonite, uses a general-purpose compatibilizer to enhance the compatibilization between the composite material interfaces, and finally prepares a high-strength, high-wear-resistant polymer composite material suitable for bearing cages through melt blending, extrusion granulation, and melt injection molding. The preparation method is simple and the processing technology is easy to control. Before extrusion granulation, materials other than chopped glass fibers are premixed to improve the uniformity of composite material dispersion. In addition, the chopped glass fibers are added from the side feed port of the twin-screw extruder, ensuring that the structure of the glass fibers is not damaged during extrusion granulation and guaranteeing the reinforcing effect of the glass fibers. Detailed Implementation

[0035] The following provides a more detailed description of specific embodiments of the present invention. It should be understood that the illustrative description of the present invention herein is not intended to limit the scope of protection of the present invention.

[0036] Nylon 46, purchased from DSM Engineering Plastics in the Netherlands, model Stanyl;

[0037] Short-cut glass fiber powder, purchased from Shenzhen Yataida Technology Co., Ltd., model ECS-11-100 (modified with silane coupling agent).

[0038] The polytetrafluoroethylene ultrafine powder was purchased from Zhejiang Jiezhou Wannengda Technology Co., Ltd.

[0039] Polyphenylene oxide, purchased from Asahi Kasei Corporation of Japan, model number 1950J;

[0040] Polyphenylene sulfide, purchased from Chongqing Jushi New Material Technology Co., Ltd., model number GAT01;

[0041] Polyester (PET), purchased from China Resources Chemical Materials Technology Co., Ltd., model CR-8828;

[0042] Sodium-based montmorillonite, purchased from Zhejiang Fenghong New Material Co., Ltd., model number MMT-Na;

[0043] Styrene-butadiene-styrene-grafted maleic anhydride (SEBS-g-MAH) was purchased from Nanjing Deba Polymer Materials Co., Ltd.

[0044] Tri-n-butyltetradecylphosphine chloride was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0045] Perfluorodecyltriethoxysilane was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0046] Comparative Example 1 (Montmorillonite without modification)

[0047] Components of the polymer composite material: 200g polyphenylene ether, 80g montmorillonite, 150g chopped glass fiber modified with silane coupling agent, 100g polytetrafluoroethylene ultrafine powder, 40g styrene-butadiene-styrene grafted maleic anhydride, and 430g nylon 46 particles.

[0048] Step S1: Add 200g of silane coupling agent-modified chopped glass fibers to 1000ml of anhydrous ethanol, stir and disperse evenly, then add 50g of perfluorodecyltriethoxysilane. Heat and stir in a 75℃ constant temperature water bath for 3 hours, filter, and wash with anhydrous ethanol, repeating the filtration process several times. Dry the obtained hydrophobically modified chopped glass fiber powder in a vacuum drying oven at 60℃ for 9 hours to finally obtain modified chopped glass fibers.

[0049] Step S2: Place the Nylon 46 particles in an 80°C drying oven and dry for 12 hours to remove moisture.

[0050] Step S3: Weigh out polyphenylene ether, nylon 46, sodium montmorillonite, polytetrafluoroethylene ultrafine powder, and styrene-butadiene-styrene-grafted maleic anhydride, and stir them in a high-speed mixer at 50 rpm for 20 minutes until they are evenly mixed to obtain the raw material mixture.

[0051] Step S4: Add the uniformly mixed raw materials and the oleophilic modified chopped glass fibers weighed in proportion to a twin-screw extruder for melt blending and extrusion granulation. The chopped glass fibers are added from the side feed port. The extrusion temperature is 300℃, the screw speed is 240r / min, and the feeding speed is 30kg / h to obtain composite material particles.

[0052] Step S5: Dry the prepared composite material particles in a vacuum drying oven at 120°C for 12 hours.

[0053] Step S6: The dried composite material particles are injection molded using an injection molding machine at an injection temperature of 300℃.

[0054] Comparative Example 2 (short-cut glass fiber without hydrophobic modification)

[0055] Components of the polymer composite material: 200g polyphenylene ether, 80g modified montmorillonite, 150g chopped glass fiber modified with silane coupling agent, 100g polytetrafluoroethylene ultrafine powder, 40g styrene-butadiene-styrene grafted maleic anhydride, and 430g nylon 46 particles.

[0056] Step S1: Add 100g of sodium-based montmorillonite (cation exchange capacity (CEC) of 120meq / 100g) to distilled water to prepare a 10wt% solution. After stirring and reacting in a constant temperature water bath at 75℃ for 4 hours, add dropwise a 10wt% aqueous solution prepared from 42g of tri-n-butyltetradecylphosphine chloride. Continue to react in a constant temperature water bath at 75℃ for 6 hours. Filter, wash with anhydrous ethanol, repeat the filtration three times, wash with distilled water, and filter three times. Place the obtained modified organomontmorillonite in a vacuum drying oven at 110℃ and dry for 24 hours. Grind and pass through a 200-mesh sieve to obtain organomodified montmorillonite powder.

[0057] Step S2: Place the Nylon 46 particles in a drying oven at 80°C for 12 hours to remove moisture.

[0058] Step S3: Weigh the thermoplastic polymer, nylon 46, organic modified montmorillonite, polytetrafluoroethylene ultrafine powder and styrene-butadiene-styrene grafted maleic anhydride according to the proportion, and stir them in a high-speed mixer at 50 rpm for 20 minutes until they are evenly mixed to obtain the raw materials.

[0059] Step S4: Add the uniformly mixed raw materials and chopped glass fibers to a twin-screw extruder for melt blending and extrusion granulation. The chopped glass fibers are added from the side feed port. The extrusion temperature is 300℃, the screw speed is 2240r / min, and the feeding speed is 30kg / h to obtain composite material particles.

[0060] Step S5: Dry the prepared composite material particles in a vacuum drying oven at 120°C for 12 hours.

[0061] Step S6: The dried composite material particles are injection molded using an injection molding machine at an injection temperature of 300℃.

[0062] Comparative Example 3 (without compatibilizer)

[0063] Components of the polymer composite material: 200g polyphenylene ether, 80g modified montmorillonite, 150g modified chopped glass fiber with silane coupling agent, 100g polytetrafluoroethylene ultrafine powder, and 470g nylon 46 particles.

[0064] Step S1: Add 100g of sodium-based montmorillonite (cation exchange capacity (CEC) of 120meq / 100g) to distilled water to prepare a 10wt% solution. After stirring and reacting in a constant temperature water bath at 75℃ for 4 hours, add dropwise a 10wt% aqueous solution prepared from 42g of tri-n-butyltetradecylphosphine chloride. Continue to react in a constant temperature water bath at 75℃ for 6 hours. Filter, wash with anhydrous ethanol, repeat the filtration three times, wash with distilled water, and filter three times. Place the obtained modified organomontmorillonite in a vacuum drying oven at 110℃ and dry for 24 hours. Grind and pass through a 200-mesh sieve to obtain organomodified montmorillonite powder.

[0065] Step S2: Add 200g of silane coupling agent-modified chopped glass fibers to 1000ml of anhydrous ethanol, stir and disperse evenly, then add 50g of perfluorodecyltriethoxysilane. Heat and stir in a 75℃ constant temperature water bath for 3 hours, filter, and wash several times with anhydrous ethanol. Dry the obtained hydrophobically modified chopped glass fiber powder in a vacuum drying oven at 60℃ for 9 hours to obtain modified chopped glass fibers.

[0066] Step S3: Place the Nylon 46 particles in an 80°C drying oven for 12 hours to remove moisture.

[0067] Step S4: Weigh out polyphenylene ether, nylon 46, organic modified montmorillonite, and polytetrafluoroethylene ultrafine powder according to the proportion, and stir them in a high-speed mixer at 50 rpm for 20 minutes until they are evenly mixed to obtain the raw materials.

[0068] Step S5: Add the uniformly mixed raw materials and the oleophilic modified chopped glass fibers weighed in proportion to a twin-screw extruder for melt blending and extrusion granulation. The chopped glass fibers are added from the side feed port. The extrusion temperature is 300℃, the screw speed is 240r / min, and the feeding speed is 30kg / h to obtain composite material particles.

[0069] Step S6: Dry the prepared composite material particles in a vacuum drying oven at 120°C for 12 hours.

[0070] Step S7: The dried composite material particles are injection molded using an injection molding machine at an injection temperature of 300℃.

[0071] Comparative Example 4 (Excessive Addition of Montmorillonite)

[0072] Components of the polymer composite material: 200g polyphenylene ether, 150g modified montmorillonite, 150g modified chopped glass fiber with silane coupling agent, 100g polytetrafluoroethylene ultrafine powder, 40g styrene-butadiene-styrene grafted maleic anhydride, and 360g nylon 46 particles.

[0073] Step S1: Add 100g of sodium-based montmorillonite (cation exchange capacity (CEC) of 120meq / 100g) to distilled water to prepare a 10wt% solution. After stirring and reacting in a constant temperature water bath at 75℃ for 4 hours, add dropwise a 10wt% aqueous solution prepared from 42g of tri-n-butyltetradecylphosphine chloride. Continue to react in a constant temperature water bath at 75℃ for 6 hours. Filter, wash with anhydrous ethanol, repeat the filtration three times, wash with distilled water, and filter three times. Place the obtained modified organomontmorillonite in a vacuum drying oven at 110℃ and dry for 24 hours. Grind and pass through a 200-mesh sieve to obtain organomodified montmorillonite powder.

[0074] Step S2: Add 200g of silane coupling agent-modified chopped glass fibers to 1000ml of anhydrous ethanol, stir and disperse evenly, then add 50g of perfluorodecyltriethoxysilane. Heat and stir in a 75℃ constant temperature water bath for 3 hours, filter, and wash several times with anhydrous ethanol. Dry the obtained hydrophobically modified chopped glass fiber powder in a vacuum drying oven at 60℃ for 9 hours to finally obtain modified chopped glass fibers.

[0075] Step S3: Place the Nylon 46 particles in an 80°C drying oven for 12 hours to remove moisture.

[0076] Step S4: Weigh out polyphenylene ether, nylon 46, organic modified montmorillonite, polytetrafluoroethylene ultrafine powder, and styrene-butadiene-styrene grafted maleic anhydride according to the proportions, and stir them in a high-speed mixer at 50 rpm for 20 minutes until they are evenly mixed.

[0077] Step S5: Add the uniformly mixed raw materials and the oleophilic modified chopped glass fibers weighed in proportion to a twin-screw extruder for melt blending and extrusion granulation. The chopped glass fibers are added from the side feed port. The extrusion temperature is 300℃, the screw speed is 240r / min, and the feeding speed is 30kg / h.

[0078] Step S6: Dry the prepared composite material particles in a vacuum drying oven at 120°C for 12 hours.

[0079] Step S7: The dried composite material particles are injection molded using an injection molding machine at an injection temperature of 300℃.

[0080] Compare with Example 5 (using Nylon 66).

[0081] Components of the polymer composite material: 200g polyphenylene ether, 80g modified montmorillonite, 150g modified chopped glass fiber with silane coupling agent, 100g polytetrafluoroethylene ultrafine powder, 40g styrene-butadiene-styrene grafted maleic anhydride, and 430g nylon 66 particles.

[0082] Step S1: Add 100g of sodium montmorillonite (cation exchange capacity (CEC) of 120meq / 100g) to distilled water to prepare a 10wt% solution. After stirring and reacting in a constant temperature water bath at 75℃ for 4 hours, add dropwise a 10wt% aqueous solution prepared from 42g of tri-n-butyltetradecylphosphine chloride. Continue to react in a constant temperature water bath at 75℃ for 6 hours. Filter, wash with anhydrous ethanol, repeat the filtration three times, wash with distilled water, and filter three times. Place the obtained modified organomontmorillonite in a vacuum drying oven at 110℃ and dry for 24 hours. Grind and pass through a 200-mesh sieve to obtain organomontmorillonite powder.

[0083] Step S2: Add 200g of silane coupling agent-modified chopped glass fibers to 1000ml of anhydrous ethanol, stir and disperse evenly, then add 50g of perfluorodecyltriethoxysilane. Heat and stir in a 75℃ constant temperature water bath for 3 hours, filter, and wash several times with anhydrous ethanol. Dry the obtained hydrophobically modified chopped glass fiber powder in a vacuum drying oven at 60℃ for 9 hours to finally obtain modified chopped glass fibers.

[0084] Step S3: Place the Nylon 66 particles in an 80°C drying oven for 12 hours to remove moisture.

[0085] Step S4: Weigh out polyphenylene ether, nylon 66, organic modified montmorillonite, polytetrafluoroethylene ultrafine powder, and styrene-butadiene-styrene grafted maleic anhydride according to the proportions, and stir them in a high-speed mixer at 50 rpm for 20 minutes until they are evenly mixed to obtain the raw materials.

[0086] Step S5: Add the uniformly mixed raw materials and the oleophilic modified chopped glass fibers weighed in proportion to a twin-screw extruder for melt blending and extrusion granulation. The chopped glass fibers are added from the side feed port. The extrusion temperature is 300℃, the screw speed is 240r / min, and the feeding speed is 30kg / h to obtain composite material particles.

[0087] Step S6: Dry the prepared composite material particles in a vacuum drying oven at 120°C for 12 hours.

[0088] Step S7: The dried composite material particles are injection molded using an injection molding machine at an injection temperature of 300℃.

[0089] Example 1

[0090] Components of the polymer composite material: 200g polyphenylene ether, 80g modified montmorillonite, 150g modified chopped glass fiber with silane coupling agent, 100g polytetrafluoroethylene ultrafine powder, 40g styrene-butadiene-styrene grafted maleic anhydride, and 430g nylon 46 particles.

[0091] Step S1: Add 100g of sodium montmorillonite (cation exchange capacity (CEC) of 120meq / 100g) to distilled water to prepare a 10wt% solution. After stirring and reacting in a constant temperature water bath at 75℃ for 4 hours, add dropwise a 10wt% aqueous solution prepared from 42g of tri-n-butyltetradecylphosphine chloride. Continue to react in a constant temperature water bath at 75℃ for 6 hours. Filter, wash with anhydrous ethanol, repeat the filtration three times, wash with distilled water, and filter three times. Place the obtained modified organomontmorillonite in a vacuum drying oven at 110℃ and dry for 24 hours. Grind and pass through a 200-mesh sieve to obtain organomontmorillonite powder.

[0092] Step S2: Add 200g of silane coupling agent-modified chopped glass fibers to 1000ml of anhydrous ethanol, stir and disperse evenly, then add 50g of perfluorodecyltriethoxysilane. Heat and stir in a 75℃ constant temperature water bath for 3 hours, filter, and wash several times with anhydrous ethanol. Dry the obtained hydrophobically modified chopped glass fiber powder in a vacuum drying oven at 60℃ for 9 hours to finally obtain modified chopped glass fibers.

[0093] Step S3: Place the Nylon 46 particles in an 80°C drying oven for 12 hours to remove moisture.

[0094] Step S4: Weigh out polyphenylene ether, nylon 46, organic modified montmorillonite, polytetrafluoroethylene ultrafine powder, and styrene-butadiene-styrene grafted maleic anhydride according to the proportions, and stir them in a high-speed mixer at 50 rpm for 20 minutes until they are evenly mixed to obtain the raw materials.

[0095] Step S5: Add the uniformly mixed raw materials and the oleophilic modified chopped glass fibers weighed in proportion to a twin-screw extruder for melt blending and extrusion granulation. The chopped glass fibers are added from the side feed port. The extrusion temperature is 300℃, the screw speed is 240r / min, and the feeding speed is 30kg / h to obtain composite material particles.

[0096] Step S6: Dry the prepared composite material particles in a vacuum drying oven at 120°C for 12 hours.

[0097] Step S7: The dried composite material particles are injection molded using an injection molding machine at an injection temperature of 300℃.

[0098] Example 2

[0099] Components of the polymer composite material: 200g polyphenylene sulfide, 80g modified montmorillonite, 150g modified chopped glass fiber with silane coupling agent, 100g polytetrafluoroethylene ultrafine powder, 40g styrene-butadiene-styrene grafted maleic anhydride, and 430g nylon 46 particles.

[0100] Step S1: Add 100g of sodium-based montmorillonite (cation exchange capacity (CEC) of 120meq / 100g) to distilled water to prepare a 10wt% solution. After stirring and reacting in a constant temperature water bath at 75℃ for 4 hours, add dropwise a 10wt% aqueous solution prepared from 42g of tri-n-butyltetradecylphosphine chloride. Continue to react in a constant temperature water bath at 75℃ for 6 hours. Filter, wash with anhydrous ethanol, repeat the filtration three times, wash with distilled water, and filter three times. Place the obtained modified organomontmorillonite in a vacuum drying oven at 110℃ and dry for 24 hours. Grind and pass through a 200-mesh sieve to obtain organomodified montmorillonite powder.

[0101] Step S2: Add 200g of silane coupling agent-modified chopped glass fibers to 1000ml of anhydrous ethanol, stir and disperse evenly, then add 50g of perfluorodecyltriethoxysilane. Heat and stir in a 75℃ constant temperature water bath for 3 hours, filter, and wash several times with anhydrous ethanol. Dry the obtained hydrophobically modified chopped glass fiber powder in a vacuum drying oven at 60℃ for 90 hours to finally obtain modified chopped glass fibers.

[0102] Step S3: Place the Nylon 46 particles in an 80°C drying oven for 12 hours to remove moisture.

[0103] Step S4: Weigh out polyphenylene sulfide, nylon 46, organic modified montmorillonite, polytetrafluoroethylene ultrafine powder, and styrene-butadiene-styrene grafted maleic anhydride according to the proportions, and stir them in a high-speed mixer at 50 rpm for 20 minutes until they are evenly mixed to obtain the raw materials.

[0104] Step S5: Add the uniformly mixed raw materials and the oleophilic modified chopped glass fibers weighed in proportion to a twin-screw extruder for melt blending and extrusion granulation. The chopped glass fibers are added from the side feed port. The extrusion temperature is 300℃, the screw speed is 240r / min, and the feeding speed is 30kg / h to obtain composite material particles.

[0105] Step S6: Dry the prepared composite material particles in a vacuum drying oven at 120°C for 12 hours.

[0106] Step S7: The dried composite material particles are injection molded using an injection molding machine at an injection temperature of 300℃.

[0107] Example 3

[0108] Polymer composite material components: 200g polyester, 80g modified montmorillonite, 150g modified chopped glass fiber with silane coupling agent, 100g polytetrafluoroethylene ultrafine powder, 40g styrene-butadiene-styrene grafted maleic anhydride, and 430g nylon 46 particles.

[0109] Step S1: Add 100g of sodium-based montmorillonite (cation exchange capacity (CEC) of 120meq / 100g) to distilled water to prepare a 10wt% solution. After stirring and reacting in a constant temperature water bath at 75℃ for 4 hours, add dropwise a 10wt% aqueous solution prepared from 42g of tri-n-butyltetradecylphosphine chloride. Continue to react in a constant temperature water bath at 75℃ for 6 hours. Filter, wash with anhydrous ethanol, repeat the filtration three times, wash with distilled water, and filter three times. Place the obtained modified organomontmorillonite in a vacuum drying oven at 110℃ and dry for 24 hours. Grind and pass through a 200-mesh sieve to obtain organomodified montmorillonite powder.

[0110] Step S2: Add 200g of silane coupling agent-modified chopped glass fibers to 1000ml of anhydrous ethanol, stir and disperse evenly, then add 50g of perfluorodecyltriethoxysilane. Heat and stir in a 75℃ constant temperature water bath for 3 hours, filter, and wash several times with anhydrous ethanol. Dry the obtained hydrophobically modified chopped glass fiber powder in a vacuum drying oven at 60℃ for 9 hours to finally obtain modified chopped glass fibers.

[0111] Step S3: Place the Nylon 46 particles in an 80°C drying oven for 12 hours to remove moisture.

[0112] Step S4: Weigh out polyester, nylon 46, organic modified montmorillonite, polytetrafluoroethylene ultrafine powder, and styrene-butadiene-styrene grafted maleic anhydride according to the proportions, and stir them in a high-speed mixer at 50 rpm for 20 minutes until they are evenly mixed to obtain the raw materials.

[0113] Step S5: Add the uniformly mixed raw materials and the oleophilic modified chopped glass fibers weighed in proportion to a twin-screw extruder for melt blending and extrusion granulation. The chopped glass fibers are added from the side feed port. The extrusion temperature is 300℃, the screw speed is 240r / min, and the feeding speed is 30kg / h to obtain composite material particles.

[0114] Step S6: Dry the prepared composite material particles in a vacuum drying oven at 120°C for 12 hours.

[0115] Step S7: The dried composite material particles are injection molded using an injection molding machine at an injection temperature of 300℃.

[0116] Example 4

[0117] Components of the polymer composite material: 300g polyphenylene ether, 80g modified montmorillonite, 150g modified chopped glass fiber with silane coupling agent, 100g polytetrafluoroethylene ultrafine powder, 40g styrene-butadiene-styrene grafted maleic anhydride, and 330g nylon 46 particles.

[0118] Step S1: Add 100g of sodium-based montmorillonite (cation exchange capacity (CEC) of 120meq / 100g) to distilled water to prepare a 10wt% solution. After stirring and reacting in a constant temperature water bath at 75℃ for 4 hours, add dropwise a 10wt% aqueous solution prepared from 42g of tri-n-butyltetradecylphosphine chloride. Continue to react in a constant temperature water bath at 75℃ for 6 hours. Filter, wash with anhydrous ethanol, repeat the filtration three times, wash with distilled water, and filter three times. Place the obtained modified organomontmorillonite in a vacuum drying oven at 110℃ and dry for 24 hours. Grind and pass through a 200-mesh sieve to obtain organomodified montmorillonite powder.

[0119] Step S2: Add 200g of silane coupling agent-modified chopped glass fibers to 1000ml of anhydrous ethanol, stir and disperse evenly, then add 50g of perfluorodecyltriethoxysilane. Heat and stir in a 75℃ constant temperature water bath for 3 hours, filter, and wash several times with anhydrous ethanol. Dry the obtained hydrophobically modified chopped glass fiber powder in a vacuum drying oven at 60℃ for 9 hours to finally obtain modified chopped glass fibers.

[0120] Step S3: Place the Nylon 46 particles in an 80°C drying oven for 12 hours to remove moisture.

[0121] Step S4: Weigh out polyphenylene ether, nylon 46, organic modified montmorillonite, polytetrafluoroethylene ultrafine powder, and styrene-butadiene-styrene grafted maleic anhydride according to the proportions, and stir them in a high-speed mixer at 50 rpm for 20 minutes until they are evenly mixed to obtain the raw materials.

[0122] Step S5: Add the uniformly mixed raw materials and the oleophilic chopped glass fibers weighed in proportion to a twin-screw extruder for melt blending and extrusion granulation. The chopped glass fibers are added from the side feed port. The extrusion temperature is 300℃, the screw speed is 240r / min, and the feeding speed is 30kg / h.

[0123] Step S6: Dry the prepared composite material particles in a vacuum drying oven at 120°C for 12 hours.

[0124] Step S7: The dried composite material particles are injection molded using an injection molding machine at an injection temperature of 300℃.

[0125] The performance testing methods for polymer composite materials are as follows:

[0126] Water absorption rate: Test method: GB / T1034-2008, see the test method for water absorption in water at 23℃.

[0127] Tensile strength: Test method: GB / T 1040.2 / 1A-2006, see the test method for tensile strength of type 1A specimen.

[0128] Compressive strength: Test method: GB / T 1041-2008, see Test Method for Compression Properties of Plastics.

[0129] Coefficient of friction: Test method: GB / T 3960-1983(1989) shall be adopted, see the test method for sliding friction and wear of plastics.

[0130] Wear mark width: Test method: GB / T 3960-1983(1989), see Plastic sliding friction and wear test method.

[0131] The composite materials prepared in Comparative Examples 1, 2, 3, 4, and 5, as well as Examples 1, 2, 3, and 4, were tested for water absorption, tribological properties, and mechanical properties. The results are as follows:

[0132]

[0133] Comparing Comparative Example 1 and Example 1, it can be seen that after organic modification of sodium-based montmorillonite, the water absorption rate of the polymer composite material decreased, the tensile and compressive strengths of the material increased, the coefficient of friction decreased, and the wear resistance of the material improved. This is because the water absorption rate of montmorillonite itself decreased after organic modification, while the compatibility between organic montmorillonite and the composite material increased, improving the mechanical properties of the composite material and its friction and wear resistance.

[0134] Comparing Comparative Example 2 and Example 1, it can be seen that further modification of the chopped glass fibers reduces the water absorption rate of the polymer composite material, increases its strength, and improves its tribological properties. Further hydrophobic modification of the chopped glass fibers further reduces their water absorption rate, while improving the compatibility between the glass fibers and the polymer, thus enhancing mechanical strength. Furthermore, the improved compatibility between the glass fibers and the polymer makes it less likely for the glass fibers to detach from the polymer and become abrasive particles during surface-to-surface grinding, further improving tribological properties.

[0135] Comparing Comparative Example 3 and Example 1, it can be seen that the addition of compatibilizer improves the overall performance of the material, such as strength. The addition of compatibilizer improves the compatibility between composite materials, increases the interfacial interaction between materials, and improves the overall performance of the material.

[0136] Comparing Comparative Example 4 and Example 1, it can be seen that the addition of excessive montmorillonite reduces the strength and wear resistance of the composite material. The addition of excessive montmorillonite increases the proportion of inorganic materials in the composite material, reduces the bonding force of the material, and decreases the mechanical properties and wear resistance of the material.

[0137] Comparing Comparative Example 5 and Example 1, it can be seen that when nylon 66 is used as the matrix material, both the tensile strength and compressive strength of the composite material decrease, while the wear of the composite material increases. This is because the mechanical strength and wear resistance of nylon 66 are lower than those of nylon 46.

[0138] Comparing Examples 1, 2, and 3, it can be seen that adding equal proportions of polyphenylene ether, polyphenylene sulfide, and polyester results in slight differences in the composite material's tensile water absorption, tensile strength, compressive strength, and tribological properties, but the differences are not significant.

[0139] Comparing Examples 1 and 4, it can be seen that as the amount of polyphenylene ether added increases, the water absorption rate of the composite material decreases, the mechanical strength of the composite material increases, the coefficient of friction of the material increases slightly, but the wear of the material decreases, and the increased strength of the material increases the wear resistance of the material.

Claims

1. A composite material for bearing cages, characterized in that, The product comprises the following components by weight percentage: 10-30% thermoplastic polymer, 5-10% modified montmorillonite, 10-20% modified chopped glass fiber, 5-15% lubricant, 3-5% compatibilizer, and the balance being nylon particles; wherein the thermoplastic polymer is one or more of polyphenylene sulfide, polyester, and polyphenylene ether. The modified montmorillonite is an organically modified montmorillonite obtained by modifying sodium-based montmorillonite with tri-n-butyltetradecylphosphine chloride; the modified chopped glass fiber is an oleophilic chopped glass fiber obtained by further modifying chopped glass fiber modified with a silane coupling agent with perfluorodecyltriethoxysilane; the compatibilizer is styrene-butadiene-styrene-grafted maleic anhydride; and the nylon particles are nylon 46 particles.

2. The composite material for a bearing cage according to claim 1, characterized in that, The lubricant is ultrafine polytetrafluoroethylene powder with an average particle size of 5 μm and a specific surface area of ​​10 m². 2 / g.

3. A method for preparing a composite material for a bearing cage according to any one of claims 1 or 2, characterized in that it comprises: Weigh out the thermoplastic polymer, modified montmorillonite, modified chopped glass fiber, lubricant, compatibilizer, and nylon particles according to the specified proportions. Thermoplastic polymer, nylon particles, modified montmorillonite, lubricant, and compatibilizer are mixed evenly in a high-speed mixer to obtain the raw material; The uniformly mixed raw materials and modified chopped glass fibers are added to a twin-screw extruder for melt blending and extrusion granulation. The modified chopped glass fibers are added from the side feed port to obtain composite material particles. The composite material particles are dried in a vacuum drying oven, and then the dried composite material particles are injection molded using an injection molding machine.

4. The method for preparing a composite material for a bearing cage according to claim 3, characterized in that, The modified montmorillonite is prepared as follows: Sodium montmorillonite was added to distilled water to prepare a solution. After stirring the reaction in a constant temperature water bath, an aqueous solution of tri-n-butyltetradecylphosphine chloride was added dropwise, and the reaction continued in a constant temperature water bath. The modified organo-montmorillonite was obtained by filtration and washing, then placed in a vacuum drying oven and ground to obtain organo-modified montmorillonite powder.

5. The method for preparing a composite material for a bearing cage according to claim 3, characterized in that, The modified chopped glass fiber is prepared as follows: Short-cut glass fibers modified with silane coupling agent were added to anhydrous ethanol, stirred and dispersed evenly, and then perfluorodecyltriethoxysilane was added. The mixture was heated and stirred in a constant temperature water bath, then filtered, washed, and vacuum dried to obtain modified short-cut glass fibers.

Images