Water-lubricated composite material, preparation method thereof and bearing
By adding microgels and fiber materials to water-lubricated bearing materials, the problem of severe friction and wear under water lubrication conditions has been solved, resulting in a low coefficient of friction and improved wear resistance, thus extending the service life of underwater equipment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- 超滑科技(佛山)有限责任公司
- Filing Date
- 2025-12-30
- Publication Date
- 2026-05-19
AI Technical Summary
The bearings of existing underwater equipment suffer from severe friction and wear, high noise, high energy consumption and short service life under water lubrication conditions. In particular, it is difficult to form a lubricating water film under boundary lubrication conditions. Ultra-high molecular weight polyethylene has low surface hardness, poor resistance to abrasive wear and poor surface wettability.
By adding microgels and high-modulus fiber materials to ultra-high molecular weight polyethylene matrix materials, the microgels improve surface wettability to form a hydrated layer, and the fiber materials enhance hardness and wear resistance, thus preparing a water-lubricated composite material.
Under water lubrication conditions, the material exhibits a low coefficient of friction and wear resistance, significantly improving the friction performance and service life of the bearing.
Smart Images
Figure CN121427205B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of polymer materials technology, and in particular to a water-lubricated composite material and its preparation method, as well as a bearing. Background Technology
[0002] Friction and wear of key components in underwater equipment can cause problems such as high noise, high energy consumption, and short service life, severely restricting the development of underwater equipment. Currently, ship bearings are mainly oil-lubricated metal materials, which has the disadvantages of consuming large amounts of oil and causing environmental pollution. Water-lubricated bearings, as important components of propulsion systems, primarily fail through wear. Under conditions of equipment start-up and shutdown, and low-speed heavy loads, the bearing bushes are in a boundary lubrication state, making it difficult to form a lubricating water film on the surface, leading to severe friction and wear accompanied by abnormal vibration and noise. Ultra-high molecular weight polyethylene (UHMWPE) has advantages such as chemical corrosion resistance, low water swelling, and good self-lubricating properties, meeting the material selection requirements for water-lubricated bearings. However, pure UHMWPE has problems such as low surface hardness, poor resistance to abrasive wear, and poor wear resistance under stress. Furthermore, in water-lubricated bearing applications, UHMWPE has low surface energy and poor surface wettability, making it difficult to form a stable water film. Summary of the Invention
[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a water-lubricated composite material, its preparation method, and a bearing.
[0004] The first aspect of this invention provides a method for preparing a water-lubricated composite material, comprising the following steps:
[0005] The water-lubricated composite material is prepared by hot pressing and sintering ultra-high molecular weight polyethylene, fiber materials and microgels.
[0006] The preparation method of the microgel includes the following steps:
[0007] Methacrylethyl sulfobetaine, N,N-methylenebisacrylamide, and ammonium persulfate were mixed in an aqueous solution to obtain solution A;
[0008] Tween 80 and Span 80 were mixed in n-hexane to obtain solution B;
[0009] Solution A was added to solution B under ice bath conditions, and then the reaction was carried out under inert gas protection and at 65 ℃-75 ℃. The emulsion was broken, the solid product was collected, washed, and freeze-dried to obtain the microgel.
[0010] The mass ratio of the methacryloylethyl sulfobetaine, the N,N-methylenebisacrylamide, the ammonium persulfate, the Tween 80, and the Span 80 is (2500-3000):(60-65):(2-3):(500-600):(1500-1800);
[0011] The fiber material includes at least one of carbon fiber, glass fiber, and aramid fiber.
[0012] This invention uses ultra-high molecular weight polyethylene (UHMWPE) as the matrix material and incorporates microgels and fiber materials to prepare a water-lubricated composite material. Pure UHMWPE has low surface hardness, poor resistance to abrasive wear, and poor wear resistance under heavy loads. Furthermore, UHMWPE has low surface energy, poor surface wettability, and difficulty in forming a stable water film, resulting in unsatisfactory water-lubricated friction performance. This invention incorporates microgels into the UHMWPE matrix material to improve surface wettability, facilitating the formation of a hydrated layer and thus enhancing friction performance. Simultaneously, fiber materials with high elastic modulus (such as carbon fiber, glass fiber, and aramid fiber) are added to the matrix material to improve hardness and wear resistance. Through the hydration and lubrication effect of the microgels and the mechanical reinforcement of the fiber materials, the friction performance of UHMWPE is improved, resulting in a water-lubricated composite material with a low coefficient of friction and high wear resistance under water lubrication conditions.
[0013] The specific principle behind the improvement in friction performance through the addition of microgels is that, due to the inherent dipole moment of water molecules, charged groups on the sliding interface can electrostatically fix oppositely charged groups in water molecules, forming a hydrated layer. The friction between the two friction pairs is then transformed into friction between two surface water molecules. The high load-bearing capacity and fluidity of the hydrated layer effectively reduce energy dissipation during relative motion of the friction surfaces, thus providing efficient lubrication. Because hydrogels contain a large number of hydrophilic functional groups, the polar functional groups of the molecular chains can rapidly form a hydrated layer under water lubrication.
[0014] Preferably, tetrahydrofuran is used as the demulsifier.
[0015] Preferably, the washing includes the following steps: washing the solid product obtained from demulsification with tetrahydrofuran.
[0016] Preferably, by weight, the ultra-high molecular weight polyethylene comprises 83-87 parts, the fiber material comprises 8-12 parts, and the microgel comprises 3-7 parts.
[0017] Preferably, the powder is obtained by mixing the ultra-high molecular weight polyethylene, the fiber material and the microgel; the specific conditions for hot pressing sintering are as follows: the powder is transferred into a mold, heated from room temperature to 160℃-180℃ in 1-3 hours, then cooled to 110℃-120℃ at a rate of 2℃ / min-3℃ / min, held at that temperature for 1-3 hours, and finally cooled to 30℃-50℃.
[0018] Preferably, the hot pressing sintering uses a cylindrical mold with a diameter of 30 mm.
[0019] Preferably, the inert gas is nitrogen.
[0020] Preferably, the pressure of the hot pressing sintering is 15 MPa-20 MPa.
[0021] A second aspect of the present invention provides a water-lubricated composite material, which is prepared by the above-described method for preparing water-lubricated composite materials.
[0022] A third aspect of the present invention provides a bearing comprising the above-described water-lubricated composite material.
[0023] The beneficial effects of this invention are as follows: This invention uses ultra-high molecular weight polyethylene as the matrix material. By adding microgels to the matrix material, the wettability of the material surface is improved, which is conducive to the formation of a hydrated layer on the material surface, thereby improving the friction performance. At the same time, high-modulus fiber materials are added to the matrix to improve the hardness and wear resistance of the material. Through the synergistic effect of microgels and fiber materials, the friction performance of ultra-high molecular weight polyethylene is improved, so that the prepared water-lubricated composite material has a low coefficient of friction and wear resistance under water lubrication conditions. Attached Figure Description
[0024] Figure 1 This is a flowchart of the preparation method of the microgel in Example 1;
[0025] Figure 2 Here is an electron micrograph of the microgel prepared in Example 1;
[0026] Figure 3 Thermogravimetric analysis of the microgels prepared in Example 1;
[0027] Figure 4 This is a comparison chart of the friction coefficient curves of the products obtained in each embodiment and comparative example. Detailed Implementation
[0028] The following will provide a clear and complete description of the concept and technical effects of the present invention in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, solution and effects of the present invention. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.
[0029] Example 1
[0030] A water-lubricated composite material, the preparation method of which includes the following steps:
[0031] By weight, 85 parts of ultra-high molecular weight polyethylene, 10 parts of carbon fiber and 5 parts of microgel were thoroughly mixed to obtain powder. The powder was then transferred to a cylindrical mold with a diameter of 30 mm for hot pressing and sintering (the pressure of hot pressing and sintering was set to 20 MPa). The temperature was raised from room temperature to 160 °C within 2 hours, and then cooled to 120 °C at a rate of 2 °C / min. The temperature was held at 120 °C for 2 hours, and then cooled to 30 °C for demolding. After polishing, a water-lubricated composite material was obtained.
[0032] Among them, reference Figure 1 The preparation method of the above-mentioned microgels includes the following steps:
[0033] In a 10 mL beaker, methacryloylethyl sulfobetaine (2.79 g), N,N-methylenebisacrylamide (61.6 mg, 4 mol%) and ammonium persulfate (2.28 mg, 0.1 mol%) were dissolved in 5 mL of deionized water to obtain solution A;
[0034] Dissolve 0.56 g of Tween 80 and 1.72 g of Span 80 in 100 mL of n-hexane to obtain solution B;
[0035] Solution A prepared above was added dropwise to solution B prepared above under ice bath conditions, and the resulting mixture was reacted at 70 °C for 3 hours under a nitrogen atmosphere. After the reaction was completed, the mixture was cooled to room temperature, tetrahydrofuran was added to break the emulsion, filtered, washed with tetrahydrofuran to remove unreacted monomers, and finally lyophilized to obtain microgels.
[0036] Figure 2 The image shown is an electron microscope image of the microgel prepared in Example 1, which shows that the prepared microgel exhibits a spherical shape.
[0037] Figure 3 The thermogravimetric curve of the microgel prepared in Example 1 is shown. It can be seen that the microgel has strong water absorption. The mass loss from the initial temperature to 100°C is the water absorbed by the microgel.
[0038] Example 2
[0039] A water-lubricated composite material, the preparation method of which includes the following steps:
[0040] By weight, 85 parts of ultra-high molecular weight polyethylene, 10 parts of glass fiber and 5 parts of microgel were thoroughly mixed to obtain powder. The powder was then transferred to a cylindrical mold with a diameter of 30 mm for hot pressing and sintering (the pressure of hot pressing and sintering was set to 20 MPa). The temperature was raised from room temperature to 160 °C within 2 hours, and then cooled to 120 °C at a rate of 2 °C / min. The temperature was held at 120 °C for 2 hours, and then cooled to 30 °C for demolding. After polishing, a water-lubricated composite material was obtained.
[0041] The preparation method of the above-mentioned microgel includes the following steps:
[0042] In a 10 mL beaker, methacryloylethyl sulfobetaine (2.79 g), N,N-methylenebisacrylamide (61.6 mg, 4 mol%) and ammonium persulfate (2.28 mg, 0.1 mol%) were dissolved in 5 mL of deionized water to obtain solution A;
[0043] Dissolve 0.56 g of Tween 80 and 1.72 g of Span 80 in 100 mL of n-hexane to obtain solution B;
[0044] Solution A prepared above was added dropwise to solution B prepared above under ice bath conditions, and the resulting mixture was reacted at 70 °C for 3 hours under a nitrogen atmosphere. After the reaction was completed, the mixture was cooled to room temperature, tetrahydrofuran was added to break the emulsion, filtered, washed with tetrahydrofuran to remove unreacted monomers, and finally lyophilized to obtain microgels.
[0045] Example 3
[0046] A water-lubricated composite material, the preparation method of which includes the following steps:
[0047] By weight, 85 parts of ultra-high molecular weight polyethylene, 10 parts of aramid fiber and 5 parts of microgel were thoroughly mixed to obtain powder. The powder was then transferred to a cylindrical mold with a diameter of 30 mm for hot pressing and sintering (the pressure of hot pressing and sintering was set to 20 MPa). The temperature was raised from room temperature to 160 °C within 2 hours, and then cooled to 120 °C at a rate of 2 °C / min. The temperature was held at 120 °C for 2 hours, and then cooled to 30 °C for demolding. After polishing, a water-lubricated composite material was obtained.
[0048] The preparation method of the above-mentioned microgel includes the following steps:
[0049] In a 10 mL beaker, methacryloylethyl sulfobetaine (2.79 g), N,N-methylenebisacrylamide (61.6 mg, 4 mol%) and ammonium persulfate (2.28 mg, 0.1 mol%) were dissolved in 5 mL of deionized water to obtain solution A;
[0050] Dissolve 0.56 g of Tween 80 and 1.72 g of Span 80 in 100 mL of n-hexane to obtain solution B;
[0051] Solution A prepared above was added dropwise to solution B prepared above under ice bath conditions, and the resulting mixture was reacted at 70 °C for 3 hours under a nitrogen atmosphere. After the reaction was completed, the mixture was cooled to room temperature, tetrahydrofuran was added to break the emulsion, filtered, washed with tetrahydrofuran to remove unreacted monomers, and finally lyophilized to obtain microgels.
[0052] Comparative Example 1
[0053] A water-lubricating material, the preparation method of which includes the following steps:
[0054] By weight, 100 parts of ultra-high molecular weight polyethylene were transferred to a cylindrical mold with a diameter of 30 mm and hot-pressed for sintering (the hot-pressing pressure was set to 20 MPa). The temperature was raised from room temperature to 160 °C within 2 hours, then cooled to 120 °C at a rate of 2 °C / min. The temperature was held at 120 °C for 2 hours, and then cooled to 30 °C for demolding. After polishing, the water-lubricated material was obtained.
[0055] Comparative Example 2
[0056] A water-lubricated composite material, the preparation method of which includes the following steps:
[0057] By weight, 95 parts of ultra-high molecular weight polyethylene and 5 parts of microgel were thoroughly mixed to obtain powder. The powder was then transferred to a cylindrical mold with a diameter of 30 mm for hot pressing and sintering (the pressure of hot pressing and sintering was set to 20 MPa). The temperature was raised from room temperature to 160 °C within 2 hours, and then cooled to 120 °C at a rate of 2 °C / min. The temperature was held at 120 °C for 2 hours, and then cooled to 30 °C for demolding. After polishing, a water-lubricated composite material was obtained.
[0058] The preparation method of the above-mentioned microgel includes the following steps:
[0059] In a 10 mL beaker, methacryloylethyl sulfobetaine (2.79 g), N,N-methylenebisacrylamide (61.6 mg, 4 mol%) and ammonium persulfate (2.28 mg, 0.1 mol%) were dissolved in 5 mL of deionized water to obtain solution A;
[0060] Dissolve 0.56 g of Tween 80 and 1.72 g of Span 80 in 100 mL of n-hexane to obtain solution B;
[0061] Solution A prepared above was added dropwise to solution B prepared above under ice bath conditions, and the resulting mixture was reacted at 70 °C for 3 hours under a nitrogen atmosphere. After the reaction was completed, the mixture was cooled to room temperature, tetrahydrofuran was added to break the emulsion, filtered, washed with tetrahydrofuran to remove unreacted monomers, and finally lyophilized to obtain microgels.
[0062] Performance Testing and Result Analysis
[0063] Friction coefficient determination: The friction coefficient of the products prepared in each embodiment and comparative example was determined using a UMT rotary friction and wear tester. The friction pair was a silicon nitride ball with a diameter of 10 mm. The rotation speed was 100 rpm, the linear velocity was 0.05 m / s, the load weight was 15 N, the test environment was 3% NaCl solution, and the test time was 1 hour.
[0064] Wear rate determination: The wear rate of the products prepared in each example and comparative example was determined using a white light diffractometer;
[0065] Wear depth measurement: The wear depth of the products prepared in each example and comparative example was measured using a white light diffractometer;
[0066] Wetting test: The water contact angle of the product surface prepared in each example and comparative example was measured using a water contact angle meter.
[0067] Table 1. Test results of friction coefficient, wear rate, wear depth, and water contact angle.
[0068]
[0069] Referring to Table 1, the friction coefficient test results of each embodiment and comparative example were analyzed. Comparative Example 1 used only ultra-high molecular weight polyethylene to prepare the water-lubricating material, with a friction coefficient of 0.062, and the friction coefficient showed a continuous upward trend with increasing friction time. Comparative Example 2 added microgel to the ultra-high molecular weight polyethylene matrix material, and its friction coefficient decreased to 0.034. This is because the uniformly dispersed microgel improved the wettability of the ultra-high molecular weight polyethylene surface, and quickly formed a hydration layer under water lubrication conditions, thereby reducing the friction coefficient. Based on the ultra-high molecular weight polyethylene matrix material and microgel, Examples 1, 2, and 3 added carbon fiber, glass fiber, and aramid fiber to the ultra-high molecular weight polyethylene matrix material, respectively. The friction coefficients of the products obtained were reduced to 0.008, 0.028, and 0.019, respectively. Adding fiber materials with high elastic modulus improves the mechanical properties of the material. During the friction process, the fibers bear part of the load and play a supporting role, which is beneficial to reducing the friction coefficient of the water-lubricated composite material.
[0070] Referring to Table 1, the test results of wear rate and wear depth for each embodiment and comparative example were analyzed. Comparative example 1 used only ultra-high molecular weight polyethylene to prepare the water lubricating material, and the wear rate was 6.44 × 10⁻⁶. -5 mm 3 / (N·m), with a wear depth of 6μm. In Comparative Example 2, the addition of microgels to the ultra-high molecular weight polyethylene matrix slightly reduced the wear rate to 6.30×10⁻⁶. - 5 The wear rate remained at 6 μm, with a wear depth of 6 mm³ / (N·m), indicating that while introducing microgel alone can improve interfacial lubrication, the improvement in wear resistance is limited because the overall mechanical properties of the matrix material are not significantly enhanced. Based on the ultra-high molecular weight polyethylene matrix material and microgel, the addition of fiber material in Examples 1, 2, and 3 resulted in a certain decrease in wear rate, which was 2.34 × 10⁻⁶ mm³ / (N·m). -5 mm 3 / (N·m), 1.54×10 -5 mm 3 / (N·m) and 2.74 ×10 -5 mm 3 The wear depth also decreased to 4 μm, 2.5 μm, and 4 μm, respectively, due to the support effect of the added fiber material on the water-lubricated composite material during the friction process, which significantly improved the tribological properties. Among them, the water-lubricated composite material doped with glass fiber prepared in Example 2 showed the largest decrease, with the wear rate reduced by 76% compared with Comparative Example 1.
[0071] Referring to Table 1, the wettability test results of each embodiment and comparative example were analyzed. Comparative Example 1 used only ultra-high molecular weight polyethylene to prepare the water-lubricating material, with a surface water contact angle of 94°. Comparative Example 2 added microgels to the ultra-high molecular weight polyethylene matrix material, and the surface water contact angle decreased to 82°, indicating that the addition of microgels can significantly reduce the wettability of the material surface. Based on the ultra-high molecular weight polyethylene matrix material and microgels, fiber materials were added to Examples 1, 2, and 3. Due to the inertness of the fiber material surface, the surface contact angles of Examples 1-3 increased slightly compared to Comparative Example 2, reaching 85°, 84°, and 83° respectively, but were still lower than Comparative Example 1. This indicates that the addition of fiber materials has a certain impact on the surface wettability of the prepared water-lubricating composite material. However, the microgels can still play a major role in hydrophilic regulation on the surface of the water-lubricating composite material, enabling the water-lubricating composite material to maintain good overall wettability.
[0072] Based on the test results, this invention incorporates microgels into the ultra-high molecular weight polyethylene (UHMWPE) matrix material to improve the surface wettability of the material, which is conducive to the formation of a hydrated layer on the material surface, thereby enhancing frictional performance. Simultaneously, fiber materials with high elastic modulus, including at least one of carbon fiber, glass fiber, and aramid fiber, are added to the matrix material to improve the material's hardness and wear resistance. Through the hydration and lubrication effect of the microgels and the mechanical reinforcement of the fiber materials, the frictional performance of UHMWPE is improved, resulting in a water-lubricated composite material with a low coefficient of friction and high wear resistance under water lubrication conditions.
[0073] The preferred embodiments of the present invention have been described in detail above, but the present disclosure is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of the present disclosure.
Claims
1. A method for preparing a water-lubricated composite material, characterized in that, Includes the following steps: The water-lubricated composite material is prepared by hot pressing and sintering ultra-high molecular weight polyethylene, fiber materials and microgels. The preparation method of the microgel includes the following steps: Methacrylethyl sulfobetaine, N,N-methylenebisacrylamide, and ammonium persulfate were mixed in an aqueous solution to obtain solution A; Tween 80 and Span 80 were mixed in n-hexane to obtain solution B; Solution A was added to solution B under ice bath conditions, and then the reaction was carried out under inert gas protection and at 65 ℃-75 ℃. The emulsion was broken, the solid product was collected, washed, and freeze-dried to obtain the microgel. The mass ratio of the methacryloylethyl sulfobetaine, the N,N-methylenebisacrylamide, the ammonium persulfate, the Tween 80, and the Span 80 is (2500-3000):(60-65):(2-3):(500-600):(1500-1800); The fiber material includes at least one of carbon fiber, glass fiber, and aramid fiber; By weight, the ultra-high molecular weight polyethylene comprises 83-87 parts, the fiber material comprises 8-12 parts, and the microgel comprises 3-7 parts.
2. The method for preparing the water-lubricated composite material according to claim 1, characterized in that: The demulsifier used is tetrahydrofuran.
3. The method for preparing the water-lubricated composite material according to claim 1, characterized in that: The washing process includes the following steps: The solid product obtained from demulsification was washed with tetrahydrofuran.
4. The method for preparing the water-lubricated composite material according to claim 1, characterized in that: The powder is obtained by mixing the ultra-high molecular weight polyethylene, the fiber material and the microgel; the specific conditions for hot pressing sintering are as follows: the powder is transferred into a mold, heated from room temperature to 160 ℃-180 ℃ in 1 hour to 3 hours, then cooled to 110 ℃-120 ℃ at a rate of 2 ℃ / min-3 ℃ / min, held at that temperature for 1 hour to 3 hours, and finally cooled to 30 ℃-50 ℃.
5. The method for preparing the water-lubricated composite material according to claim 1, characterized in that: The hot pressing sintering uses a cylindrical mold with a diameter of 30 mm.
6. The method for preparing the water-lubricated composite material according to claim 1, characterized in that: The inert gas is nitrogen.
7. The method for preparing the water-lubricated composite material according to claim 1, characterized in that: The pressure for hot pressing and sintering is 15 MPa-20 MPa.
8. A water-lubricated composite material, characterized in that, The water-lubricated composite material is prepared by the method described in any one of claims 1-7.
9. A bearing, characterized in that, Including the water-lubricated composite material as described in claim 8.