Gear cleaning composition and preparation method thereof

Abstract

The invention discloses a gear cleaning composition and a preparation method thereof, and belongs to the technical field of gear cleaning agents. The gear cleaning composition comprises the following components in parts by weight: 60-75 parts of modified base oil, 10-20 parts of a cleaning agent, 5-10 parts of a self-repairing auxiliary agent, 3-6 parts of a dispersing agent, 1-3 parts of an antioxidant and 2-5 parts of a cosolvent, wherein the self-repairing auxiliary agent comprises a modified solid, a compatible reinforcing agent and an auxiliary repairing agent in a mass ratio of (70-85): (5-10): (5-10). Wherein the modified base oil can cooperate with the cleaning agent to efficiently remove oil stains and impurities on the surface of the gear; the self-repairing additive can fill the wear defect, and the dispersing agent and the cosolvent can guarantee the uniformity and stability of the system. The gear cleaning composition integrates cleaning, lubricating, repairing and protecting functions, solves the problem that an existing cleaning agent is single in function, is suitable for gear maintenance under various working conditions, and has excellent comprehensive performance and application value.

Description

Technical Field

[0001] The present application belongs to the technical field of gear cleaning agents, and specifically relates to a gear cleaning composition and a preparation method thereof. Background Art

[0002] Gear processing requires extremely high cleanliness levels. Tiny contaminant particles can severely impact gear precision and performance, leading to tooth surface damage, reduced precision, premature wear, and shortened service life. Therefore, cleaning is not only a critical step in ensuring product quality, but also an important measure for improving production efficiency. Cleaning effectively removes chips, oil, and other contaminants generated during processing, thereby ensuring gear surface quality and precision, reducing equipment wear, and extending equipment life.

[0003] Most existing cleaning agents have targeted effects in single aspects such as cleaning, rust prevention and lubrication, but they fail to consider the possibility of simultaneously achieving rust prevention and lubrication while ensuring the cleaning effect, and they are even unable to achieve the advanced function of self-repairing gear surface defects. Summary of the Invention

[0004] The purpose of this application is to provide a gear cleaning composition and a preparation method thereof, which can simultaneously clean, rust-proof, lubricate and self-repair the gears.

[0005] To achieve the above objectives, the present application provides a gear cleaning composition comprising the following components in parts by weight: 60-75 parts of modified base oil, 10-20 parts of detergent, 5-10 parts of self-repairing agent, 3-6 parts of dispersant, 1-3 parts of antioxidant and 2-5 parts of cosolvent; The self-healing agent includes a modified solid, a compatibility enhancer and an auxiliary repair agent in a mass ratio of (70~85):(5~10):(5~10).

[0006] Furthermore, the modified base oil is prepared by the following method: Ultrasonic treatment is performed on the base oil composition and the nano-silicon dioxide dispersion to obtain a premixed solution; heating the premixed liquid under vacuum to obtain a pretreated base oil; The pretreated base oil is grafted with polar groups to obtain an intermediate product; The intermediate product is modified by double bond cross-linking to obtain a modified base oil; wherein, The base oil composition is a composition of bio-based base oil and synthetic ester oil or hydroisomerized mineral oil, and the mass fraction of the bio-based base oil in the base oil composition is 10% to 20%.

[0007] Further, the grafting process comprises the following steps: Heat the pretreated base oil to 120-140°C, introduce nitrogen protection, and add maleic anhydride and initiator in sequence, stirring and reacting for 2-3 hours; wherein, The initiator is di-tert-butyl peroxide, and maleic anhydride and di-tert-butyl peroxide account for 3% to 5% and 0.5% to 1% of the mass of the pretreated base oil respectively.

[0008] Further, the double bond cross-linking modification treatment includes the following steps: After mixing the intermediate product with methacrylate monomer and photoinitiator, irradiate with ultraviolet light for 1h~1.5h; wherein, Methacrylate monomers and photoinitiators account for 2%~4% and 0.3%~0.6% of the mass of the pretreated base oil, respectively.

[0009] Furthermore, the self-repairing agent is prepared by the following method: Molybdenum disulfide powder and silane coupling agent were mixed in a mass ratio of 10:1, ethanol was added to immerse the powder, and magnetic stirring was performed at 60°C for 2 hours to obtain a modified solid; The modified solid, the compatibility enhancer, and the auxiliary repair agent are mixed, and 5 wt% to 8 wt% of the modified base oil are added and ground together to obtain a dispersion; The dispersion was vacuum dried at 80°C to a constant weight, crushed and passed through a 200-mesh sieve to obtain a self-healing agent; The auxiliary repair agent includes at least one of metal nanoparticles, metal oxide nanoparticles, carbon-based nanoparticles and ceramic nanoparticles.

[0010] Furthermore, the antioxidant includes at least one of 3,5-di-tert-butyl-4-hydroxyphenylpropionate, 2,6-di-tert-butyl-p-cresol, p-phenylenediamine, TPPi (triphenyl phosphite), BHT (butylated hydroxytoluene) and TNPP (tris(4-nonphenyl)phosphite).

[0011] Furthermore, the cosolvent includes at least one of γ-valerolactone, acetylated monoglyceride, propylene glycol methyl ether, propylene glycol phenyl ether and ethylene glycol monobutyl ether.

[0012] Furthermore, the dispersant includes at least one of polyoxyethylene sorbitan fatty acid ester, sodium dodecylbenzenesulfonate and cetyltrimethylammonium bromide.

[0013] Furthermore, the cleaning agent includes citric acid and D-limonene in a mass ratio of (1-5):1.

[0014] To achieve the above objectives, the present application also provides a method for preparing the gear cleaning composition, comprising the following steps: Heat the modified base oil to 50°C~60°C, and add antioxidant, cosolvent and dispersant in sequence, stirring at a speed of 200r / min~300r / min for 15min~20min; The detergent is added and stirred for 10 minutes, and then the self-repairing agent is added, dispersed under ultrasound assistance for 20 minutes to 30 minutes, and cooled to obtain the product.

[0015] In summary, this application has the following advantages: The composition provided in the present application, the detergent, dispersant and co-solvent can be combined to quickly dissolve oil stains and stably disperse them in the modified base oil, thereby achieving a rapid cleaning effect; the adsorption film formed by the modified base oil can produce a lubricating synergistic effect with the self-repairing agent, which can reduce gear wear, and at the same time the antioxidant can inhibit oil oxidation, thereby maintaining the stability of the lubricating synergy; the self-repairing agent can penetrate and fill nanoparticles into surface defects during the operation of the gear, and the polar groups in the modified base oil and the compatibility enhancer can jointly enhance the bonding force between the repair layer and the metal surface, thereby achieving the multiple functions of "cleaning, lubricating and repairing at the same time". BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of a method for preparing a gear cleaning composition according to an embodiment of the present application; Figure 2 Schematic diagram of the grafting process for this application. DETAILED DESCRIPTION

[0017] The principles and features of the present invention are described below in conjunction with the examples. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention. Where specific conditions are not specified in the examples, they are carried out according to conventional conditions or conditions recommended by the manufacturer. Where the manufacturer of the reagents or instruments is not specified, they are all conventional products that can be purchased commercially.

[0018] Traditional cleaning agents only focus on cleaning or lubrication. This application achieves the four-in-one function of "cleaning, rust prevention, lubrication, and self-repair" through the synergy of multiple components. In particular, the self-repair function can actively improve the surface condition of the gear, thereby improving accuracy and life. Specifically, this application provides a gear cleaning composition, including the following components by weight: 60-75 parts of modified base oil, 10-20 parts of detergent, 5-10 parts of self-repairing agent, 3-6 parts of dispersant, 1-3 parts of antioxidant and 2-5 parts of cosolvent; The self-healing agent includes a modified solid, a compatibility enhancer and an auxiliary repair agent in a mass ratio of (70~85):(5~10):(5~10).

[0019] In the above scheme, the modified base oil is the core carrier and functional enhancer of the gear cleaning composition of the present application. As the solvent carrier of the composition, it can dissolve the remaining functional additives to form a uniform and stable composition system; the antioxidant can inhibit the oxidation reaction of the modified base oil and the metal surface of the gear in a high temperature and oxygen environment, thereby preventing the oil from deteriorating and the acid value from increasing, and avoiding corrosion to the gear; the cosolvent can enhance the compatibility of each component (especially polar components such as detergents and self-repairing agents) with the modified base oil, prevent stratification or precipitation, and ensure the homogeneity of the composition; the dispersant can be adsorbed on the surface of pollutant (such as chips, oil stains) particles through surface activity, so that the pollutants are dispersed in the oil, preventing the pollutants from re-attaching to the gear surface and improving the cleaning efficiency; the detergent can specifically remove grease, metal debris and oxides on the gear surface; the self-repairing agent can repair microscopic defects (such as scratches and wear pits) on the gear surface through physical filling and chemical adsorption, restore surface accuracy, and thus extend the life of the gear.

[0020] The gear cleaning composition provided in the present application has the following characteristics: ① In the cleaning stage, the detergent can quickly dissolve the oil stains, the dispersant can stably disperse the oil stain particles in the modified base oil, and the cosolvent can ensure the compatibility of the system, thereby avoiding oil stain residues after cleaning. ② In the lubrication stage, the adsorption film formed by the modified base oil works synergistically with the molybdenum disulfide solid lubricant to reduce the gear meshing friction coefficient, thereby reducing wear; the antioxidant inhibits the oxidation of the oil, thereby maintaining the stability of the lubricating film. ③ In the repair stage, the nanoparticles in the self-repairing additive penetrate and fill surface defects under the micro-contact pressure of the gear operation, while the stearic acid and the polar groups of the modified base oil jointly enhance the bonding force between the repair layer and the metal surface, achieving the multiple functions of "cleaning, lubricating, and repairing at the same time".

[0021] As some preferred embodiments of the present application, the gear cleaning composition includes the following components in parts by weight: 60-65 parts of modified base oil, 12-15 parts of detergent, 8-10 parts of self-repairing agent, 3-4 parts of dispersant, 1-3 parts of antioxidant and 4-5 parts of cosolvent; The self-healing agent includes a modified solid, a compatibility enhancer and an auxiliary repair agent in a mass ratio of (75~82): (8~10): 10.

[0022] As the best embodiment of the present application, the gear cleaning composition includes the following components in parts by weight: The self-healing agent comprises 64 parts modified base oil, 15 parts detergent, 10 parts self-healing agent, 3 parts dispersant, 3 parts antioxidant, and 5 parts cosolvent. The self-healing agent consists of a modified solid, a compatibilizer, and an auxiliary repair agent in a mass ratio of 80:10:10. This solution, with a detergent-to-modified base oil ratio of 15:64, creates an optimal dissolution-dispersion system that quickly penetrates and removes stubborn oil contaminants from gear crevices. The cosolvent content (5%) ensures that the cleaned oil is easily evaporated or replaced by subsequent lubricants, minimizing residual contaminants. Within the self-healing agent, the modified solid (80%) provides the repair material, the compatibilizer (10%) ensures dispersibility, and the auxiliary repair agent (10%) enhances boundary lubrication. These three components form a closed "repair-protect" loop, making it particularly suitable for preventive maintenance of highly loaded gears, such as those in heavy machinery. The combination of a dispersant (3%) and a cosolvent (5%) ensures the nanoparticles remain stable in the oil, preventing sedimentation. The antioxidant (3%) maintains the composition's performance at high temperatures (such as those found in gearboxes), providing a wider range of applications. Furthermore, the core functional ingredients (cleaning agent and self-healing agent) comprise 25% of the total composition, limiting material costs while ensuring performance.

[0023] In a specific embodiment, the modified base oil is prepared by the following method: Ultrasonic treatment is performed on the base oil composition and the nano-silicon dioxide dispersion to obtain a premixed solution; heating the premixed liquid under vacuum to obtain a pretreated base oil; The pretreated base oil is grafted with polar groups to obtain an intermediate product; The intermediate product is modified by double bond cross-linking to obtain a modified base oil; wherein, The base oil composition is a composition of bio-based base oil and synthetic ester oil or hydroisomerized mineral oil, and the mass fraction of the bio-based base oil in the base oil composition is 10% to 20%.

[0024] In the above scheme, ultrasonic treatment allows the nano-silica to be evenly dispersed in the base oil, improving the base oil's wear resistance and anti-friction properties and reducing gear wear. Vacuum heating removes moisture and low-boiling-point impurities from the base oil, preventing contamination of the gear surface while enhancing the base oil's compatibility with polar groups. Grafting treatment introduces polar groups (such as carboxylic acid groups), giving the base oil enhanced adsorption capacity and allowing it to adhere firmly to the metal surface of the gear, forming a protective film and enhancing rust prevention and lubrication. Double-bond crosslinking modification treatment forms a network structure through crosslinking reactions, improving the base oil's high-temperature stability and film strength, preventing lubricant loss at high temperatures and extending the lubrication cycle. Furthermore, the present application incorporates 10% to 20% of bio-based base oil into the base oil, making the composition environmentally friendly and biodegradable, thereby reducing industrial pollution. It also introduces double bonds that react during the subsequent crosslinking process.

[0025] In the above scheme, the mass ratio of the base oil composition to the nano-silica dispersion is (85-95):(5-15), the silica particles have a particle size of 10 nm to 50 nm, the silica content in the nano-silica dispersion is 10 wt% to 30 wt%, and the dispersant (ethanol or toluene) content is 5 wt% to 10 wt%. This ensures that the SiO2 particles are evenly dispersed in the base oil, forming a stable colloidal system, while preventing excessive particles from causing a sudden increase in oil viscosity or a decrease in friction performance.

[0026] In the above scheme, the ultrasonic power is controlled between 200W and 500W to avoid both overheating of the base oil due to low power and the breakage of agglomerated particles due to high power. Furthermore, the ultrasonic treatment frequency is set between 20kHz and 40kHz, and the treatment duration is set between 15 and 30 minutes. In actual production, to prevent solvent volatilization caused by ultrasonic heat generation, a water cooling cycle is used to control the temperature to ≤50°C, thereby preventing evaporation of light components in the base oil and dispersant degradation.

[0027] In the above scheme, vacuum treatment removes air introduced during the ultrasonication process (to prevent oxidation), solvents (such as ethanol) in the dispersion, and low-boiling-point impurities in the base oil, thereby preventing these impurities from interfering with the subsequent cross-linking reaction. Therefore, the vacuum level must be controlled between -0.08 MPa and -0.1 MPa (nearly absolute vacuum) to ensure complete solvent evaporation. Simultaneously, the premix is ​​heated to a temperature of 60°C to 80°C for 30 to 60 minutes until the vacuum pressure gauge reading stabilizes (no bubbles escape), indicating a residual solvent content of <0.5%. During this process, silica is evenly dispersed in the base oil, forming a stable colloid that provides anchor points for polar group grafting.

[0028] In this application, bio-based base oils include soybean oil-based base oils, rapeseed oil-based base oils, palm oil-based base oils, sunflower oil-based base oils, and castor oil-based base oils. Synthetic ester oils include polyol esters, diester oils, complex ester oils, and polyester oils (polymer esters). Hydroisomerized mineral oils include low-viscosity hydroisomerized mineral oils (such as the ISOWAX series), medium-to-high viscosity hydroisomerized mineral oils (such as HC-150 and HC-500), and food-grade hydroisomerized mineral oils.

[0029] Preferably, the base oil composition may include 15 wt% rapeseed oil-based base oil and 85 wt% pentaerythritol ester. The rapeseed oil-based base oil has good lubricity and biodegradability, while the pentaerythritol ester has excellent thermal oxidative stability and low volatility. The combination of the two can improve the high-temperature stability of the composition while maintaining cleaning effectiveness.

[0030] Preferably, the base oil composition may include 12 wt% palm oil-based base oil and 88 wt% diester. Palm oil-based base oil is widely available, and diester has low viscosity and a high viscosity index, which can impart good fluidity and low-temperature performance to the cleaning composition.

[0031] Preferably, the base oil composition may include 18 wt % of soybean oil-based base oil and 82 wt % of polyol ester. The soybean oil-based base oil has good environmental performance, and the polyol ester has good lubricity, which helps to reduce gear wear.

[0032] Preferably, the base oil composition may include 10 wt% of castor oil-based base oil and 90 wt% of complex ester. Castor oil-based base oil has a unique molecular structure and complex ester has comprehensive performance. The combination of the two can improve the comprehensive performance of the cleaning composition.

[0033] Preferably, the base oil composition may include 10 wt% of sunflower oil-based base oil and 90 wt% of deeply hydroisomerized mineral oil. The sunflower oil-based base oil has good biodegradability, and the deeply hydroisomerized mineral oil has few impurities and stable performance.

[0034] In a specific embodiment, the grafting process comprises the following steps: Heat the pretreated base oil to 120-140°C, introduce nitrogen protection, and add maleic anhydride and initiator in sequence, stirring and reacting for 2-3 hours; wherein, The initiator is di-tert-butyl peroxide, and maleic anhydride and di-tert-butyl peroxide account for 3% to 5% and 0.5% to 1% of the mass of the pretreated base oil respectively.

[0035] In the above scheme, if Figure 2As shown, maleic anhydride provides strong polar groups (anhydride groups), transforming the base oil from a non-polar / weakly polar base oil into a polar base oil. This enhances compatibility with polar additives such as antioxidants, dispersants, and detergents, preventing composition stratification. Furthermore, the anhydride groups can further copolymerize with the double bonds of methacrylate monomers (such as methyl methacrylate) used in the subsequent double-bond crosslinking modification, forming a crosslinked network under UV light initiation. This further enhances the base oil's film strength and high-temperature resistance, making it less susceptible to frictional heat loss during gear cleaning. Furthermore, after the polar groups are grafted, the base oil forms a stable system with antioxidants (such as phenols and amines), dispersants (such as surfactants), and detergents in the formulation through polar interactions. This solves the "repulsion" problem of traditional non-polar base oils and polar additives, ensuring a uniform and stable composition.

[0036] In the above scheme, the temperature is controlled between 120°C and 140°C, ensuring effective decomposition of the initiator (the half-life temperature of di-tert-butyl peroxide is approximately 126°C) while preventing thermal cracking or oxidative degradation of the base oil due to excessive temperatures. A sufficient reaction time (2-3 hours) ensures sufficient grafting of the maleic anhydride. Too short a reaction time will result in insufficient grafting and limited polarity enhancement. Too long a reaction time may lead to excessive crosslinking of the molecular chains, increasing base oil viscosity.

[0037] In a specific embodiment, the double bond crosslinking modification process comprises the following steps: After mixing the intermediate product with methacrylate monomer and photoinitiator, irradiate with ultraviolet light for 1h~1.5h; wherein, Methacrylate monomers and photoinitiators account for 2% to 4% and 0.3% to 0.6% of the mass of the pretreated base oil, respectively. The wavelength of the ultraviolet light is 365nm and the power is 500W.

[0038] This application utilizes a photo-induced free radical cross-linking reaction, polymerizing methacrylate monomers with base oil molecules to create a three-dimensional network structure, thereby enhancing the film-forming properties, stability, and cleaning efficiency of the cleaning composition. The cross-linked polymer film enhances the cleaning liquid's adhesion to the gear surface, thereby prolonging its action. The three-dimensional network structure improves the oil's ability to disperse dirt, thereby preventing redeposition. The cross-linked structure also enhances the base oil's stability under high temperature and shear conditions, further improving the gear's adaptability under high-load conditions.

[0039] To avoid insufficient crosslinking due to too low a dosage, or excessive viscosity due to too high a dosage, the methacrylate monomer content is controlled at 2% to 4%. Furthermore, the initiator content affects the concentration of free radicals. If the initiator dosage is insufficient (less than 0.3%), the reaction will be too slow, while if the initiator dosage is too high, it may lead to side reactions such as chain termination.

[0040] Preferably, the methacrylate monomers include methyl methacrylate (MMA), ethyl methacrylate (EMA), and butyl methacrylate (BMA), etc. The photoinitiators include benzoin ethers (such as benzoin dimethyl ether) and acetophenones (such as 2-hydroxy-2-methylacetophenone), etc.

[0041] In a specific embodiment, the self-repairing agent is prepared by the following method: Molybdenum disulfide powder and silane coupling agent were mixed in a mass ratio of 10:1, ethanol was added to immerse the powder, and magnetic stirring was performed at 60°C for 2 hours to obtain a modified solid; The modified solid, the compatibility enhancer, and the auxiliary repair agent are mixed, and 5 wt% to 8 wt% of the modified base oil are added and ground together to obtain a dispersion; The dispersion was vacuum dried at 80° C. to a constant weight, crushed, and passed through a 200-mesh sieve to obtain a self-repairing agent.

[0042] The auxiliary repair agent includes at least one of metal nanoparticles, metal oxide nanoparticles, carbon-based nanoparticles and ceramic nanoparticles, and the compatibility enhancer is stearic acid.

[0043] In the above scheme, molybdenum disulfide serves as a solid lubricant. After being modified with a silane coupling agent to make its surface oleophilic, it can be evenly dispersed in the base oil to fill the wear gaps in the gears. The silane coupling agent can also react with the hydroxyl groups on the metal surface to enhance adsorption and prevent shedding. Stearic acid forms an adsorption film on the metal surface through the carboxyl group. At the same time, the long hydrophobic chain is compatible with the base oil, which enhances the binding force between the self-repairing agent and the system. The nano-particles provided by the auxiliary repair agent can penetrate into the micropores on the gear surface, filling defects through physical deposition or chemical reactions (such as metal oxide film repair), further improving surface smoothness. At the same time, the carboxyl groups provided by the stearic acid in this application can work together with the polar groups (such as carboxylic acid groups) provided by the modified base oil to form a dense anti-rust film on the metal surface, thereby isolating moisture and air and preventing rust on the gear surface.

[0044] Preferably, the co-grinding method is: grinding in a ball mill at a speed of 300 r / min for 30 minutes to form a uniform dispersion.

[0045] As some optional embodiments of the present application, the silane coupling agent in the modified solid can be aminosilane (such as γ-aminopropyltriethoxysilane, KH-550), methacryloxysilane (such as KH-570), mercaptosilane (such as KH-590) and epoxysilane (such as KH-560), etc.

[0046] As some optional embodiments of the present application, metal nanoparticles have a particle size of 10nm to 100nm, including nano-copper, nano-silver, and nano-nickel; metal oxide nanoparticles include aluminum oxide and titanium oxide; carbon-based nanoparticles include graphene and carbon nanotubes; and ceramic nanoparticles include silicon nitride and silicon carbide. If graphene is selected as the metal nanoparticle, its preferred lateral dimensions are 0.5μm to 2μm and its thickness is 1nm to 10nm. If carbon nanotubes are selected, its preferred diameter is 10nm to 50nm and its length is 1μm to 10μm.

[0047] As some optional embodiments of the present application, the antioxidant includes at least one of 3,5-di-tert-butyl-4-hydroxyphenylpropionate, 2,6-di-tert-butyl-p-cresol, p-phenylenediamine, TPPi, BHT, dilauryl thiodipropionate and TNPP.

[0048] In this scheme, phenolic antioxidants such as 2,6-di-tert-butyl-4-hydroxyphenylpropionate and 2,6-di-tert-butyl-p-cresol, as well as aminic antioxidants such as p-phenylenediamine, can block the oxidative chain reaction by capturing free radicals. The double-bond cross-linked base oil's network structure synergizes with the antioxidants to resist high-temperature oxidation and shear forces, ensuring the combination will not fail or deteriorate during long-term gear operation.

[0049] As some optional embodiments of the present application, the co-solvent includes at least one of γ-valerolactone, acetylated monoglyceride, propylene glycol methyl ether, propylene glycol phenyl ether and ethylene glycol monobutyl ether.

[0050] In the above scheme, cosolvents can enhance the compatibility of various components (especially polar ingredients such as detergents and self-healing agents) with the base oil, preventing stratification or precipitation and ensuring the homogeneity of the composition. For example, polar solvents such as γ-valerolactone and propylene glycol methyl ether can promote the mixing of polar substances with non-polar base oils through intermolecular forces (such as hydrogen bonds). When introducing citric acid (polar detergent) and molybdenum disulfide micropowder (self-healing agent), cosolvents can prevent "oil-water stratification" and ensure the effective release of functional ingredients during the cleaning process.

[0051] As some optional embodiments of the present application, the dispersant includes at least one of polyoxyethylene sorbitan fatty acid ester, sodium dodecylbenzenesulfonate, polyisobutylene succinimide and cetyltrimethylammonium bromide.

[0052] In the above scheme, dispersants disperse contaminants in the oil, preventing them from reattaching to the gear surface and thus improving cleaning efficiency. For example, polyoxyethylene sorbitan fatty acid esters (non-ionic) and sodium dodecylbenzene sulfonate (anionic) can coat oil contaminants with their lipophilic groups, directing the hydrophilic groups outward, thereby dispersing contaminant particles within the oil. Dispersants and detergents work together, first dissolving the oil contaminants with the detergent, and then stably dispersing the oil particles with the dispersant, preventing secondary contamination. The combined effect of dispersants and cosolvents makes the composition compatible with a variety of contaminants used in gear machining (such as mineral oil-based cutting fluids and aqueous grinding fluids), thereby expanding its application range.

[0053] As some optional embodiments of the present application, the cleaning agent includes citric acid and D-limonene in a mass ratio of (1~5):1.

[0054] In the above scheme, citric acid, a weak acid, removes metal surface oxides (such as rust) through chelation and also possesses a certain degree of oil emulsification. D-limonene, a natural solvent with strong solubility for mineral oils, animal and plant oils, can quickly break down oil stains on gear surfaces. A 1:1 ratio of citric acid to D-limonene provides both acidic cleaning and oil dissolution, making it suitable for a variety of processing oils (such as cutting oils and grinding fluids). In this application, the use of bio-based base oil and D-limonene reduces the toxicity and environmental impact of the composition, meeting the requirements of green manufacturing.

[0055] Based on the same inventive concept, the present application also provides a method for preparing the gear cleaning composition, such as Figure 1 As shown, the following steps are included: S1. Heat the modified base oil to 50°C~60°C, and add antioxidant, cosolvent and dispersant in sequence, stirring at a speed of 200r / min~300r / min for 15min~20min; S2. Add a detergent and stir for 10 minutes, then add a self-repairing agent, disperse under ultrasound assistance for 20 minutes to 30 minutes, and cool to obtain the product.

[0056] In the above scheme, antioxidants, cosolvents, and dispersants are added first and stirred to form a stable system with the base oil, preventing stratification due to polarity differences when the detergent is subsequently added. Adding the detergent and self-healing agent later ensures uniform dispersion of the functional ingredients within the stabilized base oil. Ultrasound, in particular, achieves nanoscale dispersion of the self-healing agent, preventing agglomeration. The high-frequency vibrations generated by ultrasonic treatment break up agglomerates of the self-healing agent, keeping its particle size within the ideal range. This also promotes penetration of detergent molecules into the gear micropores, enhancing cleaning depth.

[0057] As some optional implementations of the present application, the stirring speed when adding the detergent is 200 r / min~300 r / min.

[0058] As some optional embodiments of the present application, the power of ultrasonic assistance is 100 W to 400 W. When mass production is carried out, ultrasonic assisted dispersion can be replaced with a high shear emulsifier (speed 2000 r / min to 3000 r / min) to improve efficiency.

[0059] The gear cleaning composition prepared in this application is suitable for a variety of application scenarios, such as precision gear systems, including automotive gearboxes and aircraft engine gearboxes. It can remove micron-sized wear particles and avoid seizures or abnormal wear. For example, heavy-duty industrial gears, such as metallurgical and mining equipment, can use self-repairing additives to repair surface damage caused by high loads and extend maintenance cycles. For example, in automated cleaning equipment, the stirring and ultrasonic steps in the preparation process of this application are suitable for industrial assembly line operations and can be integrated into the gear cleaning production line to improve production efficiency.

[0060] The above technical solutions of the present application are described in detail below with reference to specific embodiments.

[0061] Example 1 This embodiment provides a gear cleaning composition comprising 64 parts of a modified base oil, 15 parts of a detergent, 10 parts of a self-repairing agent, 3 parts of a dispersant, 3 parts of an antioxidant, and 5 parts of a cosolvent. The self-repairing agent comprises a modified solid, a compatibility enhancer, and an auxiliary repair agent in a mass ratio of 80:10:10. The dispersant is polyisobutylene succinimide, the antioxidant is BHT, and the cosolvent is propylene glycol methyl ether. The detergent comprises citric acid and D-limonene in a mass ratio of 3:1.

[0062] The gear cleaning composition of this embodiment is particularly suitable for working environments such as automobile transmission gears (steel-steel friction pairs, medium loads), with a cleaning efficiency of >95%, a friction coefficient reduction of 20%, and is suitable for working conditions below 80°C.

[0063] The gear cleaning composition of this embodiment is prepared by the following method: (1) Preparation of modified base oil 90 wt% of a base oil composition and 10 wt% of a nano-silica dispersion were ultrasonically treated at a power of 300 W, a frequency of 20 kHz, and a duration of 30 minutes to obtain a premix. The nano-silica dispersion contained 30 wt% of 50 nm silica nanoparticles and 10 wt% of an ethanol dispersant. The base oil composition comprised 10 wt% of a castor oil-based base oil and 90 wt% of a complex ester.

[0064] The premixed liquid was heated under vacuum to obtain a pretreated base oil; wherein the vacuum degree was -0.1 MPa, the heating temperature of the premixed liquid was 60° C., and the heating holding time was 60 min.

[0065] The pretreated base oil was heated to 120°C, nitrogen was introduced for protection, and maleic anhydride and di-tert-butyl peroxide were added in sequence. The mixture was stirred and reacted for 2 hours to obtain an intermediate product. Among them, maleic anhydride and di-tert-butyl peroxide accounted for 3% and 0.5% of the mass of the pretreated base oil, respectively.

[0066] The intermediate product was mixed with MMA monomer and 2-hydroxy-2-methylacetophenone, and then irradiated with 365nm ultraviolet light at a power of 500W for 1 hour to obtain a modified base oil; among them, MMA monomer and 2-hydroxy-2-methylacetophenone accounted for 3% and 0.3% of the mass of the pretreated base oil, respectively.

[0067] (2) Preparation of modified solid Molybdenum disulfide powder and γ-aminopropyltriethoxysilane were mixed in a mass ratio of 10:1, ethanol was added to immerse the powder, and magnetic stirring was performed at 60° C. for 2 h to obtain a modified solid.

[0068] (3) Preparation of self-repairing agents The modified solid, stearic acid and auxiliary repair agent were mixed, and a portion of the modified base oil accounting for 5 wt% of the total amount of the modified base oil was added, and the mixture was ground in a ball mill at a speed of 300 r / min for 30 min to obtain a dispersion; The dispersion was vacuum dried at 80° C. to a constant weight, crushed, and passed through a 200-mesh sieve to obtain a self-repairing agent.

[0069] Among them, the auxiliary repair agent includes equal masses of nano copper (30nm) and silicon carbide (80nm).

[0070] (4) Preparation of gear cleaning composition Heat the remaining modified base oil to 60°C, and add antioxidant, cosolvent and dispersant in sequence, stirring at 300 r / min for 15 minutes; The detergent was added and stirred at the same speed for 10 minutes, and then the self-repairing agent was added, and the mixture was dispersed under the assistance of ultrasound (power of 400W) for 20 minutes, and then cooled to obtain the product.

[0071] Example 2 This embodiment provides a gear cleaning composition comprising 75 parts modified base oil, 10 parts detergent, 5 parts self-repairing agent, 3 parts dispersant, 2 parts antioxidant, and 5 parts cosolvent. The self-repairing agent comprises a modified solid, a compatibility enhancer, and an auxiliary repair agent in a mass ratio of 75:5:10. The dispersant is sodium dodecylbenzenesulfonate, the antioxidant is dilauryl thiodipropionate, the cosolvent is γ-valerolactone, and the detergent comprises citric acid and D-limonene in a mass ratio of 2:1.

[0072] The gear cleaning composition of this embodiment is particularly suitable for working environments such as aircraft engine gears (titanium alloy, high load and high temperature), has a high temperature resistance of up to 120° C., and a corrosion grade of 0 (ASTM D130).

[0073] The gear cleaning composition of this embodiment is prepared by the following method: (1) Preparation of modified base oil 90 wt% of a base oil composition and 10 wt% of a nano-silica dispersion were ultrasonically treated at a power of 300 W, a frequency of 20 kHz, and a duration of 30 minutes to obtain a premix. The nano-silica dispersion contained 30 wt% of 50 nm silica nanoparticles and 10 wt% of an ethanol dispersant. The base oil composition comprised 18 wt% of a soybean oil-based base oil and 82 wt% of trimethylolpropane trioleate.

[0074] The premixed liquid was heated under vacuum to obtain a pretreated base oil; wherein the vacuum degree was -0.1 MPa, the heating temperature of the premixed liquid was 80° C., and the heating holding time was 30 min.

[0075] The pretreated base oil was heated to 140°C, nitrogen was introduced for protection, and maleic anhydride and di-tert-butyl peroxide were added in sequence. The mixture was stirred and reacted for 2 hours to obtain an intermediate product. Among them, maleic anhydride and di-tert-butyl peroxide accounted for 5% and 1% of the mass of the pretreated base oil, respectively.

[0076] The intermediate product was mixed with MMA monomer and 2-hydroxy-2-methylacetophenone, and then irradiated with 365nm ultraviolet light at a power of 500W for 1 hour to obtain a modified base oil; among them, the MMA monomer and 2-hydroxy-2-methylacetophenone accounted for 2% and 0.6% of the mass of the pretreated base oil, respectively.

[0077] (2) Preparation of modified solid Molybdenum disulfide powder and γ-aminopropyltriethoxysilane were mixed in a mass ratio of 10:1, ethanol was added to immerse the powder, and magnetic stirring was performed at 60° C. for 2 h to obtain a modified solid.

[0078] (3) Preparation of self-repairing agents The modified solid, stearic acid and auxiliary repair agent were mixed, and a portion of the modified base oil accounting for 6 wt% of the total amount of the modified base oil was added, and the mixture was ground in a ball mill at a speed of 300 r / min for 30 min to obtain a dispersion; The dispersion was vacuum dried at 80° C. to a constant weight, crushed, and passed through a 200-mesh sieve to obtain a self-repairing agent.

[0079] Among them, the auxiliary repair agent includes equal masses of nanosilver (20nm) and silicon nitride (60nm).

[0080] (4) Preparation of gear cleaning composition Heat the remaining modified base oil to 60°C, and add antioxidant, cosolvent and dispersant in sequence, stirring at 300 r / min for 15 minutes; The detergent was added and stirred at the same speed for 10 minutes, and then the self-repairing agent was added, and the mixture was dispersed under the assistance of ultrasound (power of 100 W) for 30 minutes, and then cooled to obtain the product.

[0081] Example 3 This embodiment provides a gear cleaning composition comprising 60 parts of a modified base oil, 20 parts of a detergent, 10 parts of a self-repairing agent, 6 parts of a dispersant, 2 parts of an antioxidant, and 2 parts of a cosolvent. The self-repairing agent comprises a modified solid, a compatibility enhancer, and an auxiliary repair agent in a mass ratio of 80:10:10. The dispersant is hexadecyltrimethylammonium bromide, the antioxidant is TNPP, the cosolvent is acetylated monoglyceride, and the detergent comprises citric acid and D-limonene in a mass ratio of 2:1.

[0082] In the preparation method, the base oil composition of Example 3 includes 15 wt % of rapeseed oil-based base oil and 85 wt % of pentaerythritol ester, and the remaining steps are consistent with Example 1.

[0083] Comparative Example 1 The difference between this comparative example and Example 1 is that the modified base oil is not modified, and only 10 wt % of castor oil-based base oil and 90 wt % of complex ester are used.

[0084] Comparative Example 2 The difference between this comparative example and Example 1 is that the molybdenum disulfide powder, stearic acid, nanosilver and silicon nitride are directly mixed, vacuum dried at 80°C to constant weight, crushed and sieved through a 200-mesh sieve to prepare a self-repairing additive, and the molybdenum disulfide powder is not subjected to the modification treatment of step (2).

[0085] Comparative Example 3 The difference between this comparative example and Example 1 is that no detergent is contained.

[0086] Comparative Example 4 The difference between this comparative example and Example 1 is that no auxiliary repairing agent is contained.

[0087] Comparative Example 5 This comparative example differs from Example 1 in that no modified solid is contained.

[0088] Experimental example ① Cleanliness is determined in accordance with GB / T 3821-2005 Determination of Cleanliness of Small and Medium-Power Internal Combustion Engines. The gear to be tested is immersed in a cleaning composition to simulate the gear oil adhesion environment. After a specified time, the gear is removed and the mass of residual oil on the gear surface before and after cleaning is weighed using a precision balance to calculate the oil removal rate.

[0089] ② The self-repair performance test refers to "ISO 21741:2018 Metallic materials - Surface integrity - Surface defect repair evaluation method". A laser confocal microscope is used to scan the surface micromorphology of the gear before and after the test. The surface defect repair area is calculated using professional image analysis software, and the surface defect repair rate is then obtained.

[0090] ③ The lubricity test follows ASTM D2782 Standard Test Method for Load-Carrying Capacity of Gear Lubricants (FZG Gear Machine Method). The gear cleaning composition is applied to a standard gear testing machine to simulate actual operating conditions. The friction coefficient of the gears before and after use is measured and calculated to determine the friction coefficient reduction rate.

[0091] ④ The anti-rust performance test is carried out in strict accordance with "ASTM D130-21 Standard Test Method for Corrosion of Copper to Petroleum Products, Lubricants, and Additives". The standard metal test piece is immersed in the cleaning composition and placed in a specified temperature and humidity environment for a certain period of time. The corrosion condition of the metal test piece surface is observed and the ASTM D130 corrosion grade is determined by comparing with the standard atlas.

[0092] ⑤ Test the D90 characteristic value (ISO 13320) using laser diffraction technology: This indicates that 90% of the particle diameters are smaller than this value (in μm), reflecting the uniformity of particle dispersion. The smaller the D90, the finer the particles and the better the dispersion.

[0093] The gear cleaning compositions prepared in Examples 1-3 and Comparative Examples 1-5 were subjected to performance tests, and the results are shown in Table 1.

[0094] Table 1

[0095] As can be seen from Table 1, the compositions of Examples 1-3 have a high removal rate for oil stains, indicating that the ratio of the detergent citric acid and D-limonene is reasonable, and the dispersant and the cosolvent also produce a synergistic effect on the cleaning effect. Among them, the dispersant can effectively adsorb oil particles, and the cosolvent can enhance the compatibility of the system, so that the detergent can fully play its role. At the same time, the modified base oil serves as a solvent carrier to ensure the dissolution and dispersion of the detergent and dispersant. The base oil of Comparative Example 1 is not modified, resulting in its weak solubility and dispersion ability, which affects the effect of the detergent and dispersant, and ultimately leads to a decrease in the oil stain removal rate. Comparative Example 3 does not contain a detergent, so it cannot specifically dissolve the grease on the gear surface, which significantly reduces the oil stain removal rate.

[0096] As can be seen in Table 1, the compositions of Examples 1-3 of the present application significantly enhance the repair effect through the synergistic effect of the modified solid, compatibility enhancer, and auxiliary repair agent in the self-repair additive. The modified solid can enhance the bonding force with the gear surface, and the nanoparticles can penetrate and fill defects under micro-contact pressure. In contrast, the molybdenum disulfide in Comparative Example 2 is not modified, resulting in insufficient bonding with the gear surface, making it difficult for the nanoparticles to effectively fill the gear, thereby reducing the repair rate. The lack of an auxiliary repair agent in Comparative Example 4 results in an insufficient variety and quantity of nanoparticles, making it impossible to fill defects.

[0097] As can be seen from Table 1, the compositions of Examples 1-3 of the present application produce a synergistic effect with the molybdenum disulfide solid lubricant through the adsorption film formed by the modified base oil, further reducing the meshing friction of the gears. At the same time, under the inhibitory effect of the antioxidant, the stability of the lubricating film is maintained, reflecting the friction-reducing and synergistic effect of the maleic anhydride grafting and methacrylate monomer cross-linking modification.

[0098] Although the specific embodiments of the present application have been described in detail, this should not be construed as limiting the scope of protection of the present application. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of the present application.

Claims

1. A gear cleaning composition, characterized in that: It comprises the following components in parts by weight: 60-75 parts of modified base oil, 10-20 parts of detergent, 5-10 parts of self-repairing agent, 3-6 parts of dispersant, 1-3 parts of antioxidant and 2-5 parts of cosolvent; The self-repairing agent comprises a modified solid, a compatibility enhancer and an auxiliary repairing agent in a mass ratio of (70-85): (5-10): (5-10).

2. The gear cleaning composition according to claim 1, wherein The modified base oil is prepared by the following method: Ultrasonic treatment is performed on the base oil composition and the nano-silicon dioxide dispersion to obtain a premixed solution; heating the premixed liquid under vacuum to obtain a pretreated base oil; Grafting the pretreated base oil with polar groups to obtain an intermediate product; The intermediate product is subjected to double bond cross-linking modification to obtain a modified base oil; wherein, The base oil composition is a composition of bio-based base oil and synthetic ester oil or hydroisomerized mineral oil, and the mass fraction of the bio-based base oil in the base oil composition is 10% to 20%.

3. The gear cleaning composition according to claim 2, wherein The grafting process comprises the following steps: The pretreated base oil is heated to 120°C to 140°C, nitrogen is introduced for protection, and maleic anhydride and initiator are added in sequence, and stirred for reaction for 2h to 3h; wherein, The initiator is di-tert-butyl peroxide, and the maleic anhydride and the di-tert-butyl peroxide account for 3% to 5% and 0.5% to 1% of the mass of the pretreated base oil respectively.

4. The gear cleaning composition according to claim 2, wherein The double bond cross-linking modification process comprises the following steps: After mixing the intermediate product with a methacrylate monomer and a photoinitiator, the mixture is irradiated with ultraviolet light for 1 h to 1.5 h; wherein, The methacrylate monomer and the photoinitiator account for 2% to 4% and 0.3% to 0.6% of the mass of the pretreated base oil respectively.

5. The gear cleaning composition according to claim 1, wherein The self-repairing agent is prepared by the following method: Molybdenum disulfide powder and silane coupling agent were mixed in a mass ratio of 10:1, ethanol was added to immerse the powder, and magnetic stirring was performed at 60°C for 2 hours to obtain a modified solid; The modified solid, the compatibility enhancer, and the auxiliary repair agent are mixed, and 5 wt % to 8 wt % of the modified base oil are added and ground together to obtain a dispersion; The dispersion was vacuum dried at 80° C. to a constant weight, crushed, and passed through a 200-mesh sieve to obtain the self-repairing agent; Wherein, the auxiliary repair agent includes at least one of metal nanoparticles, metal oxide nanoparticles, carbon-based nanoparticles and ceramic nanoparticles.

6. The gear cleaning composition according to claim 1, wherein The antioxidant includes at least one of 3,5-di-tert-butyl-4-hydroxyphenylpropionate, 2,6-di-tert-butyl-p-cresol, p-phenylenediamine, TPPi and TNPP.

7. The gear cleaning composition according to claim 1, wherein The cosolvent comprises at least one of gamma-valerolactone, acetylated monoglyceride, propylene glycol methyl ether, propylene glycol phenyl ether and ethylene glycol monobutyl ether.

8. The gear cleaning composition according to claim 1, wherein The dispersant includes at least one of polyoxyethylene sorbitan fatty acid ester, sodium dodecylbenzenesulfonate and cetyltrimethylammonium bromide.

9. The gear cleaning composition according to claim 1, wherein The cleaning agent comprises citric acid and D-limonene in a mass ratio of (1-5):

1.

10. A method for preparing the gear cleaning composition according to any one of claims 1 to 9, characterized in that: The following steps are involved: Heat the modified base oil to 50° C. to 60° C., and add the antioxidant, cosolvent, and dispersant in sequence, stirring at a speed of 200 rpm to 300 rpm for 15 to 20 minutes; The cleaning agent is added and stirred for 10 minutes, and then the self-repairing agent is added, dispersed under ultrasound assistance for 20 minutes to 30 minutes, and cooled to obtain the product.

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