Modified zirconium oxide nano material as well as preparation method and application thereof

Abstract

The invention discloses a modified zirconium oxide nano material as well as a preparation method and application thereof, and relates to the technical field of nano materials. The preparation method comprises the following steps: weighing isopropanol and gamma-methacryloxypropyltrimethoxysilane (KH570), adding the isopropanol and the gamma-methacryloxypropyltrimethoxysilane (KH570) into distilled water, adding an acetic acid solution to adjust the pH value to 4-6, and uniformly mixing to obtain a mixed solution; and adding nano zirconium oxide into the mixed solution, carrying out ultrasonic dispersion for 10-15 minutes, stirring at a constant temperature, and carrying out centrifugal washing and drying to obtain the modified zirconium oxide nano material. Weighing the modified zirconium oxide nano material, adding into the lubricating oil, and carrying out ultrasonic oscillation treatment for 15-20 minutes; and putting the mixture into a magnetic stirrer, and stirring at the stirring speed of 900-1200rpm for 1.5-2 hours to obtain the uniformly dispersed modified zirconium oxide lubricating oil. The modified nano zirconium oxide is not easy to agglomerate and has good dispersion stability, the lubricating oil with uniformly dispersed zirconium oxide is obtained by adding the modified nano zirconium oxide into the lubricating oil and carrying out ultrasonic dispersion and magnetic stirring, and the lubricating oil has better antifriction and antiwear properties.

Description

Technical Field

[0001] The present invention relates to the technical field of nanomaterials, and particularly relates to a modified zirconia nanomaterial, a preparation method thereof, and uses thereof. Background Art

[0002] Bearings are generally used in mechanical equipment to support rotating components, which bear loads and rotate at high speeds. For example, the thrust bearing of a water pump operates under high temperature, high speed, and high load. Therefore, lubrication is particularly important for bearings. Nanomaterials can improve the anti-wear effect of lubricating oils, and they are used more and more in lubricating oils. Zirconia nanomaterials have extremely high surface energy, which makes them tend to agglomerate. In lubricating oils, these agglomerates cause particle sedimentation and uneven distribution, thereby affecting the friction performance of the lubricating oil and limiting their application as anti-friction and anti-wear additives.

[0003] CN106635328A discloses a preparation method of a lubricating oil containing a nano-modified material. During the preparation process, carbon nanotubes are introduced. Nano-zirconia can reduce the frictional resistance and thus improve the anti-wear effect. Carbon nanotubes have strong adsorption ability and can adsorb various additives together, and can fully exert the role of additives during friction. Then, through modification means such as magnetic force and ultrasonic waves, reactions are carried out in an atmosphere such as ammonia and carbon dioxide to further improve their antioxidant and high-temperature resistance capabilities. Among them, there are samples with a mass ratio of carbon nanotubes to nano-zirconia of 5:2. 5 parts of carbon nanotubes, 2 parts of nano-zirconia, 20 parts of heptene, 20 parts of decene, 0.2 part of zinc chloride powder, 1 part of sodium hydroxide, 2 parts of active silicon powder, 1 part of polybutenyl succinimide tetraethylene pentamine as a surfactant, 2 parts of coupling agent KH560, and 1 part of PMA. And samples with a mass ratio of carbon nanotubes to nano-zirconia of 2:7. 2 parts of carbon nanotubes, 7 parts of nano-zirconia, 20 parts of heptene, 20 parts of decene, 0.2 part of zinc chloride powder, 1 part of sodium hydroxide, 2 parts of active silicon powder, 1 part of polybutenyl succinimide tetraethylene pentamine as a surfactant, 2 parts of coupling agent KH560, and 1 part of PMA. The lubricating oils containing nano-modified materials prepared under these two ratios have the best anti-wear effect.

[0004] However, many reagents are used in the above-mentioned scheme and the preparation method is complex. Therefore, there is an urgent need to develop a more concise method for modifying zirconia nanomaterials and using them in lubricating oils. Summary of the Invention

[0005] The purpose of the present invention is to provide a modified zirconia nanomaterial, a preparation method thereof, and uses thereof, so as to solve the problem of the cumbersome and complex preparation process of the existing method.

[0006] To solve the above technical problems, the present invention adopts the following technical solutions: A preparation method of a modified zirconia nanomaterial, which is characterized by including the following steps:

[0007] S1. Weigh isopropanol and γ-methacryloxypropyltrimethoxysilane (KH570), add them to distilled water, add acetic acid solution to adjust the pH value to 4 - 6, and obtain a mixed solution after mixing evenly.

[0008] S2. Add nano-zirconia to the mixed solution, disperse it by ultrasonic for 10 - 15 minutes, then stir it at a constant temperature, and obtain the modified zirconia nano-material after centrifugal washing and drying.

[0009] A further technical solution is that the volume ratio of isopropanol to γ-methacryloxypropyltrimethoxysilane is 1:1 - 1.5, and the addition amount of nano-zirconia is 1 - 1.5 g / 40 mL.

[0010] A further technical solution is that the constant temperature stirring is carried out at 70 °C for 25 - 30 min.

[0011] A further technical solution is that the centrifugal speed is 9000 rpm and the time is 5 - 10 min.

[0012] A further technical solution is that the drying is carried out at a temperature of 70 °C for 16 - 18 h.

[0013] The present invention also protects a modified zirconia nano-material prepared by the above method.

[0014] A further technical solution is that the modified zirconia nano-material is used for preparing lubricating oil.

[0015] A further technical solution is that the preparation method of the lubricating oil is as follows:

[0016] Step 1. Weigh the modified zirconia nano-material and add it to the lubricating oil, and carry out ultrasonic oscillation treatment for 15 - 20 minutes;

[0017] Step 2. Place the mixture in Step 1 on a magnetic stirrer, and stir it at a stirring speed of 900 - 1200 rpm for 1.5 - 2 h to obtain a uniformly dispersed modified zirconia lubricating oil.

[0018] A further technical solution is that the addition amount of the modified zirconia nano-material is 0.05 - 0.5%.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: It provides a more concise preparation method for modified zirconia nano-materials. By first mixing isopropanol and γ-methacryloxypropyltrimethoxysilane (KH570) and adjusting the pH value with acetic acid, and then adding nano-zirconia to modify it, the modified nano-zirconia is not easy to agglomerate and has good dispersion stability. When the modified nano-zirconia is added to the lubricating oil, through ultrasonic dispersion and magnetic stirring, a lubricating oil with uniformly dispersed zirconia is obtained, and its friction reduction and anti-wear performance are better. Description of the Drawings

[0020] Figure 1 This is the process flow chart of the present invention.

[0021] Figure 2 This is the SEM image of the nano-zirconia in Example 1. Among them, (a) is the SEM image of the unmodified nano-zirconia, and (b) is the SEM image of the modified nano-zirconia.

[0022] Figure 3 This is the Fourier Transform Infrared (FTIR) spectrum of the modified nano-zirconia in Example 1.

[0023] Figure 4 This is the X-ray Diffraction (XRD) pattern of the modified nano-zirconia in Example 1.

[0024] Figure 5 This is the schematic diagram of the chemical reaction process in the present invention. Detailed Description of the Invention

[0025] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the following further describes the invention in detail with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0026] Example 1

[0027] Using nano-zirconia as the raw material, acetic acid, water and isopropanol as the solvents, and γ-methacryloxypropyltrimethoxysilane (KN570) as the modifier, the surface of the nano-zirconia was modified.

[0028] Step 1: Add 20 mL of isopropanol and 20 mL of γ-methacryloxypropyltrimethoxysilane (KH570) to 30 mL of distilled water, and then adjust its pH value to 4 by adding acetic acid solution to obtain a mixed solution.

[0029] Step 2: Weigh 1 g of nano-zirconia and add it to the mixed solution, and ultrasonically disperse it for 15 minutes until evenly dispersed to obtain a nano-zirconia mixed solution. The ultrasonic power is 900 W and the ultrasonic frequency is 40 Hz.

[0030] Step 3: Keep the nano-zirconia mixed solution at a constant temperature of 70 °C and stir for 30 minutes. After stirring, the centrifugation speed is 9000 rpm and the time is 5 min. After centrifugation, wash it 3 times and then dry it to obtain the modified nano-zirconia powder. The drying temperature is 70 °C and the drying time is 16 h.

[0031] The characterization results of the modified nano-zirconia are as Figures 2 to 4 shown. Figure 2In (a) is the SEM image of unmodified nano-zirconia, Figure 2 In (b) is the SEM image of modified nano-zirconia. From Figure 2 (a) and (b), it can be seen that the dispersibility of nano-zirconia particles modified by KH570 silane coupling agent is improved compared with that before modification. Figure 3 Figure (6) is the FTIR diagram of the modified nano-zirconia in the example, Figure 3 In (1) is the spectrum of KH570, (2) is the spectrum of nano-zirconia modified by KH570, and (3) is the spectrum of unmodified nano-zirconia. Figure 3 In (6), the broad absorption band near 3450 cm -1 and the peak at 1630 cm -1 are the stretching vibrations of adsorbed water and surface hydroxyl groups (-OH). The peaks at 2885 and 2932 cm -1 are the asymmetric stretching vibration and symmetric stretching vibration of -CH3. In addition, the characteristic absorption peak of Si-O-C appears near 1049 cm -1 . The absorption peaks at 1719, 1460 and 1170 cm -1 represent the stretching vibration absorption peak of C=O, the bending vibration absorption peak of -CH2 and the stretching vibration absorption peak of C-O-C. The above several groups of vibration peaks further confirm that the condensation reaction has successfully occurred between the KH570 silane coupling agent and the surface hydroxyl groups of zirconia, and confirm the success of the surface modification experiment of the silane coupling agent modified nano-zirconia. Figure 4 Figure (22) is the XRD diagram of the modified nano-zirconia in the example. Compared with the pure nano-zirconia particles, the XRD pattern of the KH570 modified nano-zirconia particles does not show obvious differences, indicating that the crystal structure of the nano-particles has not changed during the surface modification of zirconia by the KH570 silane coupling agent.

[0032] Example 2

[0033] Using nano-zirconia as the raw material, acetic acid, water and isopropanol as solvents, and γ-methacryloyloxypropyltrimethoxysilane (KN570) as the modifier, the surface of nano-zirconia was modified.

[0034] Step 1: Add 20 mL of isopropanol and 25 mL of γ-methacryloyloxypropyltrimethoxysilane (KH570) to 30 mL of distilled water, and then adjust its pH value to 4.5 by adding acetic acid solution to obtain a mixed solution.

[0035] Step 2: Weigh 1 g of nano-zirconia and add it to the mixed solution, and ultrasonically disperse it for 15 minutes until it is evenly dispersed to obtain a nano-zirconia mixed solution. The ultrasonic power is 900 W and the ultrasonic frequency is 40 hz.

[0036] Step 3: Keep the nano-zirconia mixed solution at a constant temperature of 70 °C and stir for 30 minutes. After stirring, centrifuge at a speed of 9000 rpm for 10 minutes. After centrifugation, wash 3 times and then dry to obtain modified nano-zirconia powder. The drying temperature is 70 °C and the drying time is 18 h.

[0037] In Step 1, different pH values result in different surface modification grafting rates of the obtained nano-zirconia. Under the condition of pH = 4, the surface modification grafting rate is 4.82%. Under the condition of pH = 4.5, the surface modification grafting rate is 1.33%. Under the condition of pH = 5, the surface modification grafting rate is 2.95%.

[0038] Example 3

[0039] Using nano-zirconia as the raw material, acetic acid, water and isopropanol as solvents, and γ-methacryloxypropyltrimethoxysilane (KN570) as the modifier, the surface of nano-zirconia is modified.

[0040] Step 1: Add 20 mL of isopropanol and 30 mL of γ-methacryloxypropyltrimethoxysilane (KH570) to 30 mL of distilled water, and then adjust its pH value to 5 by adding acetic acid solution to obtain a mixed solution.

[0041] Step 2: Weigh 1.5 g of nano-zirconia and add it to the mixed solution, and ultrasonically disperse for 12 minutes until evenly dispersed to obtain a nano-zirconia mixed solution. The ultrasonic power is 900 W and the ultrasonic frequency is 40 hz.

[0042] Step 3: Keep the nano-zirconia mixed solution at a constant temperature of 70 °C and stir for 30 minutes. After stirring, centrifuge at a speed of 9000 rpm for 10 minutes. After centrifugation, wash 3 times and then dry to obtain modified nano-zirconia powder. The drying temperature is 70 °C and the drying time is 16 h.

[0043] Example 4

[0044] This example provides a preparation method of modified nano-zirconia lubricating oil, specifically as follows:

[0045] Step 1: Add 0.05% of modified nano-zirconia (the modified nano-zirconia prepared in Example 1) to 30 g of lubricating oil.

[0046] Step 2: Place it in an ultrasonic disperser and perform ultrasonic oscillation treatment for 15 minutes.

[0047] Step 3: Place the modified zirconia lubricating oil obtained in Step 2 on a magnetic stirrer, stir at a speed of 900 rpm for 2 h, and after stirring, obtain uniformly dispersed modified zirconia lubricating oil.

[0048] Example 5

[0049] The difference between this example and Example 4 is that the addition amount of modified nano-zirconia is 0.1%, and the preparation process is the same as that of Example 4, that is, modified nano-zirconia lubricating oil is obtained.

[0050] Example 6

[0051] The difference between this example and Example 4 is that the mass fraction of modified nano-zirconia is adjusted to 0.3%, and the preparation process is the same as that of Example 4, that is, modified nano-zirconia lubricating oil is obtained.

[0052] Example 7

[0053] The difference between this example and Example 4 is that the mass fraction of modified nano-zirconia is adjusted to 0.5%, and the preparation process is the same as that of Example 4, that is, modified nano-zirconia lubricating oil is obtained.

[0054] The friction performance of the nano-lubricating oil prepared in the above examples was measured, and the results are shown in Table 1:

[0055] Table 1 Influence of different mass fractions of modified nano-zirconia on the friction performance of lubricating oil

[0056] nano-lubricating oil average friction coefficient average wear scar diameter (mm) Example 4 0.0938 0.818 Example 5 0.0892 0.813 Example 6 0.0753 0.581 Example 7 0.0764 0.731

[0057] As can be seen from Table 1, with the increase of the mass fraction of modified nano-zirconia, the friction coefficient and wear scar diameter of the nano-lubricating oil decrease. When the mass fraction of added modified nano-zirconia is 0.3%, both the friction coefficient and wear scar diameter are the lowest. Then, when the mass fraction of modified nano-zirconia increases to 0.5%, the friction coefficient and wear scar diameter of the nano-lubricating oil increase.

[0058] Comparative Example 1

[0059] In this comparative example, the friction performance of the lubricating oil without added nanoparticles was measured for comparison with the examples.

[0060] Comparative Example 2

[0061] This comparative example provides a preparation method of unmodified nano-zirconia lubricating oil, in which the mass fraction of unmodified nano-zirconia is 0.05%, and the preparation process is the same as that of Example 4, that is, nano-zirconia lubricating oil is obtained.

[0062] Comparative Example 3

[0063] This comparative example provides a preparation method of unmodified nano-zirconia lubricating oil, and the mass fraction of unmodified nano-zirconia is adjusted to 0.1%, and the preparation process is the same as that of Example 4, that is, nano-zirconia lubricating oil is obtained.

[0064] Comparative Example 4

[0065] This comparative example provides a method for preparing unmodified nano-zirconia lubricating oil. The mass fraction of unmodified nano-zirconia is adjusted to 0.3%, and the preparation process is the same as that of Example 4, thus obtaining nano-zirconia lubricating oil.

[0066] Comparative Example 5

[0067] This comparative example provides a method for preparing unmodified nano-zirconia lubricating oil. The mass fraction of unmodified nano-zirconia is adjusted to 0.5%, and the preparation process is the same as that of Example 4, thus obtaining nano-zirconia lubricating oil.

[0068] The friction performance of the nano-lubricating oil prepared in the above comparative examples was measured and compared with that of the examples. The results are shown in Table 2:

[0069] Table 2 Comparison of Friction Performance

[0070]

[0071]

[0072] It can be seen from Table 2 that after the nano-zirconia is modified by the method of the present invention, the friction coefficient and wear scar diameter of the prepared nano-lubricating oil are greatly reduced. Compared with the base oil, the average friction coefficient of the modified nano-zirconia lubricating oil is reduced by up to 40.71%. However, the average friction coefficient of the unmodified zirconia lubricating oil is reduced by about 16.54% at most. It is found that adding 0.05 wt% unmodified zirconia cannot reduce the friction coefficient of the base oil under high load and high speed conditions. When the concentration of the modified zirconia additive is 0.3 wt%, the wear scar diameter is only 0.581 mm, which is reduced by 20.09% compared with the wear scar diameter of the pure lubricating oil. The above phenomena also indicate that the modified zirconia in the base oil effectively lubricates the interface between metals under heavy load and high friction speed conditions. The added modified zirconia alleviates the interaction between the surfaces, changes the friction mode from sliding to rolling, thereby reducing the friction of the particles. The high hardness of zirconia gives it a polishing effect, which helps to reduce the surface roughness. In addition, the alkyl chain provides stability to the dispersion and acts as an additional protective layer, thus also avoiding roughness and being beneficial to the progress of the synergistic lubrication mechanism. It shows that the modified nano-zirconia lubricating oil prepared by the present invention has excellent anti-friction and anti-wear properties.

[0073] Although the present invention has been described herein with reference to a number of illustrative embodiments of the invention, it should be understood that those skilled in the art can devise many other modifications and embodiments that will fall within the scope of the disclosure of this application. More specifically, within the scope of the disclosure of this application, the accompanying drawings, and the claims, various deformations and improvements can be made to the components or the layout. In addition to the deformations and improvements to the components or the layout, other uses will also be obvious to those skilled in the art.

Claims

1. A preparation method of a modified zirconia nanomaterial, characterized in that It includes the following steps: S1. Weigh isopropanol and γ-methacryloxypropyltrimethoxysilane, add them into distilled water, add acetic acid solution to adjust the pH value to 4-6, and obtain a mixed solution after mixing evenly; S2. Add nano zirconia into the mixed solution, ultrasonically disperse for 10-15 minutes, then stir at a constant temperature, and obtain the modified zirconia nano-material after centrifugal washing and drying.

2. The preparation method of a modified zirconia nanomaterial according to claim 1, characterized in that: The volume ratio of the isopropanol to the γ-methacryloxypropyltrimethoxysilane is 1:1-1.5, and the addition amount of the nano zirconia is 1-1.5 g / 40 mL.

3. The preparation method of a modified zirconia nanomaterial according to claim 1, characterized in that: The constant temperature stirring is to stir at 70 °C for 25-30 min.

4. The preparation method of a modified zirconia nanomaterial according to claim 1, characterized in that: The centrifugal speed is 9000 rpm and the time is 5-10 min.

5. The preparation method of a modified zirconia nanomaterial according to claim 1, characterized in that: The drying is to dry at a temperature of 70 °C for 16-18 h.

6. A modified zirconia nanomaterial, characterized in that: It is prepared by the preparation method of the modified zirconia nano-material according to any one of claims 1-5.

7. A modified zirconia nanomaterial according to claim 1, characterized in that: The modified zirconia nano-material is used for preparing lubricating oil.

8. A modified zirconia nanomaterial according to claim 7, characterized in that: The preparation method of the lubricating oil is as follows: Step 1. Weigh the modified zirconia nano-material and add it into the lubricating oil, and perform ultrasonic oscillation treatment for 15-20 minutes; Step 2. Place the mixture in step 1 on a magnetic stirrer, and stir at a stirring speed of 900-1200 rpm for 1.5-2 h to obtain a uniformly dispersed modified zirconia lubricating oil.

9. A modified zirconia nanomaterial according to claim 8, characterized in that: The addition amount of the modified zirconia nano-material is 0.05-0.5%.

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