Construction method of super-lubricating low-viscosity polar polyether modified silicone oil

Abstract

The invention belongs to the technical field of oil-based super lubrication, and particularly relates to a construction method of super-lubrication low-viscosity polar polyether modified silicone oil. The preparation method comprises the following steps: reacting allyl polyether with hydrogen-containing silicone oil according to a mass ratio of (70-80): 1 under the catalytic condition of chloroplatinic acid to obtain low-viscosity polar polyether modified silicone oil, and mixing 0.5 wt.%-1.5 wt.% of a polar additive, 0.1 wt.%-0.5 wt.% of surface functionalized nanoparticles and 97.5 wt.%-99.4 wt.% of the low-viscosity polar polyether modified silicone oil according to mass percent to obtain the compound lubricating oil. Performing ultrasonic treatment on the composite lubricating oil, and standing to obtain the super-lubricating low-viscosity polar polyether modified silicone oil. The polar additive molecules and the small-size and easy-to-disperse functional nanoparticles are compounded at the same time, so that the interaction between a lubricating film and a friction surface is remarkably enhanced in a cross-scale manner, and a friction pair motion interface is promoted to form a friction composite film with high bearing and low shearing characteristics; and stable ultralow friction and abrasion under the working conditions of wide rotating speed and wide load are achieved, and theoretical and technical supports are provided for engineering application of the oil-based super-lubrication technology.

Description

Technical Field

[0001] This invention belongs to the field of oil-based superlubricating technology, specifically relating to a method for constructing a superlubricating, low-viscosity, polar polyether-modified silicone oil. Background Technology

[0002] As large machinery operates in environments characterized by high loads, long lifespans, and compact designs, increasingly stringent technical requirements are being placed on the friction-reduction and wear-resistant properties of critical moving components. Superlubricating materials, with their near-zero friction and wear characteristics, hold promise for fundamentally solving this problem. However, solid lubrication has been reported to suffer from environmental sensitivity and insufficient load-bearing capacity, while water-based lubrication is limited by material adaptability and temperature sensitivity. Therefore, developing oil-based superlubricating systems has become a key approach to promoting the engineering application of this technology.

[0003] Silicone oils, due to their flexible molecular structure, are of significant value in the development of ultra-lubricating oil-based systems. Their main chain consists of silicon-oxygen bonds (Si-O-Si), with organic side groups, endowing them with excellent thermal stability and chemical inertness. This allows them to maintain structural stability and provide effective lubrication in harsh environments such as high temperature and high pressure. Simultaneously, the compliant molecular chain facilitates the formation of an insulating lubricating film at the friction interface. However, the performance of traditional lubricants is insufficient to meet the demands of extreme operating conditions, especially under boundary lubrication conditions, where the function of lubricants is highly dependent on the lubricating film formed at the friction interface. To enhance the film-forming ability of lubricants, existing technologies mainly employ two improvement strategies: First, embedding polar functional groups into the lubricant molecular structure, such as introducing polyether groups into silicone oil, to enhance its adsorption capacity on the friction surface and guide tribochemical reactions, promoting the formation of a shear-sensitive lubricating film, thereby improving the slip state and laying the foundation for achieving ultra-low friction. Second, introducing polar lubricating additives such as carboxylic acid derivatives, amine compounds, and ethers, leveraging their polar groups to enhance interfacial adsorption capacity, thereby improving lubrication performance. However, increased lubricant polarity exacerbates the risk of tribochemical wear. Therefore, a multi-scale oil-based superlubrication system construction method with excellent adaptability to harsh operating conditions is urgently needed to address the challenges of achieving engineering superlubrication and its adaptability to such conditions.

[0004] By further reducing the size of nanoparticles and performing surface functionalization modifications, their dispersion stability in base oils can be significantly improved, their interaction with friction surfaces can be enhanced, and the formation of a strong and tough superlubricating film in situ can be promoted, thereby improving the mechanical stability and service life of the lubrication system. Summary of the Invention

[0005] This invention addresses the challenges of achieving superlubricity in engineering applications and adapting to demanding operating conditions. By further reducing the size of nanoparticles and performing surface functionalization, it improves their dispersion stability in base oils, enhances their interaction with friction surfaces, and promotes the in-situ formation of a strong and tough superlubricating film. By embedding polar functional groups into the silicone oil molecular structure and compounding them with polar additive molecules and small, easily dispersed functional nanoparticles, the interaction between the lubricating film and the friction surface is significantly enhanced across scales. This promotes the formation of a friction composite film with both high load-bearing capacity and low shear properties at the friction pair's motion interface, achieving stable ultra-low friction and wear under wide speed and load conditions. This provides theoretical and technical support for the engineering application of oil-based superlubricity technology.

[0006] To achieve the above objectives, this invention proposes a method for constructing a super-lubricating, low-viscosity polar polyether-modified silicone oil, comprising the following steps: S1. Allyl polyether and hydrogen-containing silicone oil are reacted at a mass ratio of (70~80):1 under chloroplatinic acid catalysis to obtain low-viscosity polar polyether modified silicone oil. S2. Mix 0.5wt.%-1.5wt.% polar additives, 0.1wt.%-0.5wt.% surface-functionalized nanoparticles and 97.5wt.%-99.4wt.% of the low-viscosity polar polyether modified silicone oil by mass percentage to obtain a composite lubricant. S3. After ultrasonic treatment of the composite lubricating oil, it is allowed to stand to obtain a super-lubricating, low-viscosity, polar polyether-modified silicone oil.

[0007] Preferably, in step S1, the hydrogen content of the hydrogen-containing silicone oil is 0.15 wt.% to 0.20 wt.%.

[0008] Preferably, in step S1, during the reaction under the catalytic conditions, the reaction temperature is 110℃~120℃ and the heating time is 0.5h~2h.

[0009] Preferably, in step S2, the polar additive is trioleic acid glyceride, and the surface-functionalized nanoparticles are carboxylated graphene quantum dots.

[0010] Preferably, in step S3, the ultrasonic treatment process lasts for 4 to 8 hours and the frequency is 70 to 90 Hz.

[0011] Preferably, in step S3, the settling time is 1 to 3 hours, and the settling time is at room temperature.

[0012] Preferably, the super-lubricating low-viscosity polar polyether modified silicone oil has an average coefficient of friction of 0.017 under a fixed load of 10N and a frequency of 3Hz-15Hz. Under a fixed frequency of 15Hz and a load of 3N-15N, the average coefficient of friction is 0.016-0.022, and the specific wear rate is 1.3×10⁻⁶. -8 mm 3 / N·m-5.1×10 -8 mm 3 / N·m.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) By constructing a multi-scale synergistic system of "molecular structure-interfacial adsorption-nano reinforcement", this invention forms a high-strength, easily sheared composite lubricating film in situ at the friction interface, which significantly improves the adsorption strength and continuity of the lubricating film and effectively blocks direct contact between the friction pairs.

[0014] (2) Based on a multi-scale collaborative mechanism, this invention breaks through the working condition limitations of traditional lubrication systems and achieves stable ultra-low friction and wear in a wide load and wide speed range, thereby realizing the synergistic regulation of friction reduction and wear resistance of the lubrication system and the adaptability to working conditions. Attached Figure Description

[0015] Figure 1 The friction curve diagram provided in Embodiment 1 of the present invention; Figure 2 The average COF and specific wear rate under different reciprocating frequencies and loads provided in Embodiment 1 of the present invention are shown in (a) and (b) respectively. Figure 3 Friction curves of viscous polar polyether silicone oil and ordinary polyether silicone oil provided in Comparative Example 1 of the present invention; Figure 4 Friction curve diagram provided for Comparative Example 1 of the present invention; Figure 5 Friction curve diagram provided for Comparative Example 2 of the present invention; Figure 6 The bar charts for specific wear rate provided in Comparative Examples 1-2 of this invention. Detailed Implementation

[0016] The technical solutions of the present invention will be clearly and completely described below with reference to the data in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0017] It should be noted that the technical terms used in this invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of this invention. Unless otherwise specified, all raw materials, reagents, instruments and equipment used in the following embodiments of this invention can be purchased from the market or prepared by existing methods.

[0018] This invention proposes a method for constructing a super-lubricating, low-viscosity polar polyether-modified silicone oil, comprising the following steps: S1. Allyl polyether and hydrogen-containing silicone oil are reacted under chloroplatinic acid catalysis at a mass ratio preferably (70~80):1, for example, 70:1, 72:1, 75:1, 78:1, 80:1, to obtain low-viscosity polar polyether modified silicone oil (PESO). Specifically, in step S1, allyl polyether and hydrogen-containing silicone oil with a hydrogen content of 0.15 wt.% to 0.20 wt.% are reacted under chloroplatinic acid catalysis. The reaction temperature is preferably 110℃ to 120℃, for example, 110℃, 115℃, or 120℃, and the heating time is preferably 0.5h to 2h, for example, 0.5h, 0.8h, 1h, 1.5h, 1.8h, or 2h.

[0019] S2. The polar additive is preferably 0.5 wt.%-1.5 wt.%, for example, 0.5 wt.%, 0.8 wt.%, 1.2 wt.%, or 1.5 wt.% by mass percentage; the surface functionalized nanoparticles are preferably 0.1 wt.%-0.5 wt.%, for example, 0.1 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, or 0.5 wt.% by mass percentage; and the low viscosity polar polyether modified silicone oil is preferably 97.5 wt.%-99.4 wt.%, for example, 97.5 wt.%, 98 wt.%, 99 wt.%, or 99.4 wt.% by mass percentage. After mixing, a composite lubricating oil is obtained. Specifically, in step S2, the polar additive is trioleic acid glyceride (GT), and the surface functionalized nanoparticles are carboxylated graphene quantum dots (GQDs). Specifically, a composite lubricant is obtained by mixing 0.5 wt.% trioleic acid glyceride, 0.3 wt.% carboxylated graphene quantum dots and 99.2 wt.% low-viscosity polar polyether modified silicone oil.

[0020] S3. After ultrasonic treatment of the composite lubricating oil, it is allowed to stand to obtain a super-lubricating, low-viscosity, polar polyether-modified silicone oil. Specifically, in step S3, the composite lubricating oil is ultrasonically heated at a frequency preferably 70Hz~90Hz, for example, 70Hz, 75Hz, 80Hz, 85Hz, or 90Hz, for a time preferably 4h~8h, for example, 4h, 5h, 6h, 7h, or 8h, and then allowed to stand at room temperature for a time preferably 1h~3h, for example, 1h, 2h, or 3h.

[0021] The following specific examples will provide further explanation.

[0022] Example 1 The specific steps for preparing the super-lubricating, low-viscosity polar polyether-modified silicone oil in this embodiment are as follows: (1) Preparation of low-viscosity polar polyether silicone oil: Allyl polyether with a mass ratio of 75:1 and low-hydrogen silicone oil were reacted under chloroplatinic acid catalysis to obtain low-viscosity polar polyether modified silicone oil. The reaction temperature was 110 °C and the heating time was 1 h. (2) Preparation of low-viscosity polar polyether silicone oil with compound trioleic acid glyceride and carboxylated graphene quantum dots: 0.5 wt.% (0.1 g) trioleic acid glyceride, 0.3 wt.% (0.06 g) carboxylated graphene quantum dots and 99.2 wt.% (19.84 g) low-viscosity polar polyether silicone oil were mixed and placed in a reagent bottle. Then, the compound trioleic acid glyceride and carboxylated graphene quantum dot composite lubricating oil were mixed evenly by an ultrasonic cleaner and ultrasonicated at 80 Hz for 6 h. The composite lubricating oil obtained by ultrasonication was uniform and transparent. It was left to stand in the air for 2 h before use to prepare the low-viscosity polar polyether silicone oil with compound trioleic acid glyceride and carboxylated graphene quantum dots.

[0023] The tribological properties of a low-viscosity polar polyether silicone oil composed of compounded carboxylated graphene quantum dots and trioleic acid glyceride were tested using a UMT-3 tribometer. The contact method was ball-disk contact. The disk used was a 20 mm diameter, 5 mm thick GGr15 bearing steel disk, and the balls used were 9.525 mm diameter GGr15 bearing steel balls with a stroke of 1 mm. A constant load and constant frequency friction test was conducted: the load was 10 N, and the frequency was 5 Hz. Figure 1 As shown, the average coefficient of friction is approximately 0.038.

[0024] The resulting low-viscosity polar polyether silicone oil, composed of trioleic acid glyceride and carboxylated graphene quantum dots, was tested for average COF and specific wear rate under different reciprocating frequencies and loads. Results Figure 2 As shown in (a), under a fixed load of 10 N and a frequency of 3 Hz-15 Hz, the average friction coefficient decreased from 0.048 to 0.017, and the specific wear rate decreased from 2.43 × 10⁻⁶. -7 mm 3 / N·m decreased to 5.1×10 -8 mm 3 / N·m; Figure 2 As shown in (b), under a fixed frequency of 15 Hz and a load of 3 N-15 N, the average coefficient of friction remained stable between 0.016 and 0.022; under a load of 10 N and a frequency of 5 Hz, the specific wear rate of the low-viscosity polar polyether silicone oil compounded with trioleic acid glyceride and carboxylated graphene quantum dots was 0.9 × 10⁻⁶. -7 mm 3 / N·m; and under fixed frequency of 15Hz and load of 3N-15N, the specific wear rate is stable at 1.3×10 -8 mm 3 / N·m-5.1×10 -8 mm 3 The results show that the composite lubrication system maintains stable ultra-low friction and wear performance over a wide load and frequency range.

[0025] Example 2 This embodiment prepares a low-viscosity polar polyether silicone oil compounded with trioleic acid glyceride and carboxylated graphene quantum dots.

[0026] In step (2), 0.5 wt.% trioleic acid glyceride, 0.5 wt.% carboxylated graphene quantum dots and 99.4 wt.% low-viscosity polar polyether silicone oil are mixed together, and the remaining steps are the same as in Example 1.

[0027] The tribological properties of a low-viscosity polar polyether silicone oil composed of compounded carboxylated graphene quantum dots and trioleic acid glyceride were tested using a UMT-3 tribometer. The contact method was ball-disk contact. The disk used was a 20 mm diameter, 5 mm thick GGr15 bearing steel disk, and the balls used were 9.525 mm diameter GGr15 bearing steel balls with a stroke of 1 mm. A constant load and constant frequency friction test was conducted: the load was 10 N, and the frequency was 5 Hz. Figure 1 As shown, the average coefficient of friction is approximately 0.04. Example 3 This embodiment prepares a low-viscosity polar polyether silicone oil compounded with trioleic acid glyceride and carboxylated graphene quantum dots.

[0028] In step (2), 0.5 wt.% trioleic acid glyceride, 0.1 wt.% carboxylated graphene quantum dots and 99.4 wt.% low-viscosity polar polyether silicone oil are mixed together, and the remaining steps are the same as in Example 1.

[0029] The tribological properties of a low-viscosity polar polyether silicone oil composed of compounded carboxylated graphene quantum dots and trioleic acid glyceride were tested using a UMT-3 tribometer. The contact method was ball-disk contact. The disk used was a 20 mm diameter, 5 mm thick GGr15 bearing steel disk, and the balls used were 9.525 mm diameter GGr15 bearing steel balls with a stroke of 1 mm. A constant load and constant frequency friction test was conducted: the load was 10 N, and the frequency was 5 Hz. Figure 1 As shown, the friction coefficient is between 0.04 and 0.06 in the initial stage, and the average friction coefficient in the later stage is 0.06.

[0030] Comparative Example 1 This comparative example only uses low-viscosity polar polyether modified silicone oil for friction performance testing.

[0031] The tribological properties of low-viscosity polar polyether silicone oil were tested using a UMT-3 tribometer with ball-disc contact. The disk used was a 20 mm diameter, 5 mm thick GGr15 bearing steel disk, and the balls were 9.525 mm diameter GGr15 bearing steel balls with a stroke of 1 mm. A constant load and constant frequency friction test was conducted: load 10 N, frequency 15 Hz. Figure 3 As shown, the average coefficient of friction is 0.01-0.02, which is significantly lower than that of traditional ordinary polyether silicone oil. Perform constant load, dynamic frequency test: load is 10 N, frequency is 5 Hz, 10 Hz and 15 Hz, such as Figure 4 As shown, the coefficient of friction gradually decreases with increasing frequency, reaching a minimum of 0.01-0.02 at 15 Hz. Initially, it is 0.05 at 5 Hz, then gradually increases to 0.16. Compared to the coefficient of friction in Example 1, the coefficient of friction in this comparative example is significantly higher. The specific wear rate was measured under a load of 10 N and a frequency of 5 Hz. Figure 6 As shown, its specific wear rate is approximately 9.6 × 10⁻⁶. -7 mm 3 / N·m, which is much higher than the specific wear rate of Example 1.

[0032] Comparative Example 2 In step (2) of this comparative example, trioleic acid glyceride was used to compound low-viscosity polar polyether silicone oil. 0.005g of carboxylated graphene quantum dots and 0.995g of low-viscosity polar polyether silicone oil were mixed and placed in a reagent bottle. The remaining steps were the same as in Example 1.

[0033] The frictional properties of a low-viscosity polar polyether silicone oil compounded with trioleic acid glyceride were tested using a UMT-3 trioleic acid wear testing machine. The contact method was ball-disc contact. The disk used was a 20 mm diameter, 5 mm thick GGr15 bearing steel disk, and the balls used were 9.525 mm diameter GGr15 bearing steel balls with a stroke of 1 mm. A constant load and constant frequency friction test was conducted: the load was 10 N, and the frequency was 5 Hz. Figure 5 As shown, the average coefficient of friction of the 0.5 wt.% trioleic acid glyceride compounded with low-viscosity polar polyether silicone oil is approximately 0.05, which is higher than the average coefficient of friction in Example 1. Figure 6 It can be seen that the specific wear rate of 0.5 wt.% trioleic acid glyceride compounded with low viscosity polar polyether silicone oil is 1.66 × 10⁻⁶. -7 mm 3 The specific wear rate of the low-viscosity polar polyether silicone oil with trioleic acid glyceride was higher than that of Example 1, and the specific wear rate of the compounded trioleic acid glyceride gradually increased with the increase of the mass percentage of trioleic acid glyceride.

[0034] In summary, this invention solves the problems of lubricating film strength and stability that cannot be addressed by a single additive through the synergistic effect of trioleic acid glyceride, carboxylated graphene quantum dots, and low-viscosity polar polyether silicone oil. As a result, it exhibits a more stable and lower coefficient of friction than base oil and single ester additives under relatively harsh operating conditions (10N, 5Hz). At the same time, it obtains a more stable and reliable lubricating film than single quantum dot additives. The low-viscosity polar polyether silicone oil with trioleic acid glyceride and carboxylated graphene quantum dots compounded in this invention has a low and stable specific wear rate.

[0035] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described here to avoid redundancy. Although preferred embodiments of the invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this invention.

[0036] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for constructing a super-lubricating, low-viscosity polar polyether-modified silicone oil, characterized in that, Includes the following steps: S1. Allyl polyether and hydrogen-containing silicone oil are reacted at a mass ratio of (70~80):1 under chloroplatinic acid catalysis to obtain low-viscosity polar polyether modified silicone oil. S2. Mix 0.5wt.%-1.5wt.% polar additives, 0.1wt.%-0.5wt.% surface-functionalized nanoparticles and 97.5wt.%-99.4wt.% of the low-viscosity polar polyether modified silicone oil by mass percentage to obtain a composite lubricant. S3. After ultrasonic treatment of the composite lubricating oil, it is allowed to stand to obtain a super-lubricating, low-viscosity, polar polyether-modified silicone oil.

2. The method for constructing a super-lubricating, low-viscosity polar polyether-modified silicone oil according to claim 1, characterized in that, In step S1, the hydrogen content of the hydrogen-containing silicone oil is 0.15 wt.% to 0.20 wt.%.

3. The method for constructing a super-lubricating, low-viscosity polar polyether-modified silicone oil according to claim 1, characterized in that, In step S1, during the reaction under the catalytic conditions, the reaction temperature is 110℃~120℃ and the heating time is 0.5h~2h.

4. The method for constructing a super-lubricating, low-viscosity polar polyether-modified silicone oil according to claim 1, characterized in that, In step S2, the polar additive is trioleic acid glyceride, and the surface functionalized nanoparticles are carboxylated graphene quantum dots.

5. The method for constructing a super-lubricating, low-viscosity polar polyether-modified silicone oil according to claim 1, characterized in that, In step S3, during the ultrasonic treatment process, the ultrasonic time is 4h~8h and the frequency is 70Hz~90Hz.

6. The method for constructing a super-lubricating, low-viscosity polar polyether-modified silicone oil according to claim 1, characterized in that, In step S3, the settling time is 1 to 3 hours, and the settling time is at room temperature.

7. The method for constructing a super-lubricating, low-viscosity polar polyether-modified silicone oil according to claim 1, characterized in that, The super-lubricating, low-viscosity polar polyether-modified silicone oil has an average coefficient of friction of 0.017 under a fixed load of 10N and a frequency of 3Hz-15Hz. Under a fixed frequency of 15Hz and a load of 3N-15N, the average coefficient of friction is 0.016-0.022, and the specific wear rate is 1.3×10⁻⁶. -8 mm 3 / N·m-5.1×10 -8 mm 3 / N·m.

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