Gasoline engine oil composition and base oil molecular modification method thereof

Abstract

The present application relates to the technical field of base oil molecular structure modification, in particular to a gasoline engine oil composition and a base oil molecular modification method thereof, the composition containing 70-85 parts of modified base oil, 5-10 parts of borate ester dispersant and various additives; during preparation of the modified base oil, the base oil is first reacted with 3-mercaptopropyl trimethoxysilane, then glycidyl methacrylate and N-vinyl pyrrolidone are sequentially added, and through multi-step temperature control reaction, siloxane groups, epoxy groups and pyrrolidone groups are grafted on the molecular chain to obtain the modified base oil, which is used for preparing high-performance gasoline engine oil; through base oil molecular modification and special additive compounding, the present application improves the viscosity-temperature performance, wear resistance and oxidation stability of the gasoline engine oil and reduces the generation of deposits; the process reduces energy consumption and cost, meets environmental protection requirements and realizes the unification of high performance and economy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of base oil molecular structure modification, in particular to a gasoline engine oil composition and a base oil molecular modification method thereof. BACKGROUND

[0002] In the modern automobile industry, the performance of gasoline engine oil directly affects the service life and fuel economy of the engine. Traditional gasoline engine oil is mostly compounded by mineral base oil and conventional additives. The molecular structure of the base oil is single, and it is easy to oxidize and crack under high temperature and high load conditions, resulting in a decrease in oil viscosity and an increase in deposits, thereby shortening the oil change cycle. Although the conventional additive system can provide basic lubrication and oxidation resistance, it is difficult to meet the comprehensive requirements of anti-wear, anti-foam and low-temperature fluidity in response to the harsh working environment brought by engine miniaturization and turbocharging technology. For example, the decomposition rate of traditional diphenylamine antioxidants is relatively fast at high temperatures, which cannot provide long-term protection for oil products; the dispersion capacity of polyisobutylene-based dispersants for oil sludge is limited, which can easily cause carbon deposition inside the engine.

[0003] The existing base oil modification technology has limitations. The process cost of improving the quality of base oil through hydroisomerization is high, and it is difficult to change the polarity and adsorption performance of the base oil from the molecular level; and simple physical mixing of additives cannot form a stable synergistic network, resulting in significant performance degradation of the engine oil during long-term use. In addition, with the increasingly stringent environmental regulations on the volatility and phosphorus content of engine oil, it is difficult for traditional formulations to reduce environmental impact while maintaining high performance.

[0004] Emerging nanomaterials and ionic liquids have been tried in the field of lubricating oil, but due to poor dispersibility, high cost and insufficient compatibility with base oil, they have not been applied on a large scale. For example, unmodified graphene tends to agglomerate in oil, which can even exacerbate mechanical wear; the high viscosity characteristics of ionic liquids can significantly increase the running resistance of the engine. Therefore, it is urgent to develop a gasoline engine oil molecular modification and formulation design scheme that takes into account performance improvement and cost optimization. SUMMARY

[0005] (I) Technical problems solved

[0006] In view of the deficiencies of the prior art, the present application provides a gasoline engine oil composition and a base oil molecular modification method thereof.

[0007] (II) Technical solutions

[0008] A gasoline engine oil composition, consisting of the following components by weight: 70-85 parts of a base oil modified at the molecular level, 5-10 parts of a borate ester ashless dispersant, 3-6 parts of zinc dialkyldithiophosphate, 2-5 parts of an aromatic amine antioxidant, 4-8 parts of a methacrylate viscosity index improver, and 0.5-1.5 parts of a benzotriazole derivative metal deactivator.

[0009] The molecularly modified base oil is prepared by mixing base oil with 3-mercaptopropyl trimethoxysilane, heating to 150-180℃ under nitrogen protection, adding dibutyl tin dilaurate catalyst, then adding glycidyl methacrylate, continuing to react, and finally adding N-vinyl pyrrolidone, reacting at 80-100℃ to obtain a modified base oil with siloxane, epoxy and pyrrolidone groups grafted on the molecular chain; the chemical equation of the reaction is as follows:

[0010]

[0011]

[0012]

[0013] Preferably, 0.5-2 parts of graphene quantum dot additives are also included, the particle size of the graphene quantum dots is 2-8nm, and the surface contains hydroxyl and carboxyl functional groups, which are uniformly dispersed in the base oil by ultrasonic dispersion method.

[0014] Preferably, 1-3 parts of ionic liquid additives are also included, the ionic liquid is 1-butyl-3-methyl imidazole hexafluorophosphate, the purity is ≥99%, and the water content is ≤0.05%.

[0015] Preferably, the borate ashless dispersant is polyisobutylene-based succinimide borate, the number average molecular weight is 1000-3000, and the boron content is 1.2-2.0wt%.

[0016] Preferably, the aromatic amine antioxidant is a complex of octylated diphenylamine and N-phenyl-α-naphthylamine, the mass ratio of the two is 2:1, and contains 0.5-1.5wt% of nanometer cerium dioxide synergist.

[0017] Preferably, the base oil molecular modification method of the gasoline engine oil composition comprises the following steps:

[0018] S1: heating the base oil to 100-120℃, dehydrating for 1-2 hours under a vacuum degree of -0.08 to -0.1MPa;

[0019] S2: cooling to 60-80℃, purging nitrogen to replace air 3 times, maintaining nitrogen positive pressure at 0.02-0.03MPa after each replacement; 3-mercaptopropyl trimethoxysilane is pre-dehydrated at 40-50℃ under a vacuum degree of -0.09MPa for 1 hour, then added to the system under nitrogen protection; continue to purging nitrogen for 30 minutes to ensure the water content of the system is ≤50ppm; then heat to 150-180℃;

[0020] S3: Add dibutyltin dilaurate catalyst, maintain the temperature for 4-6 hours, and apply ultrasound at 20-40kHz during the reaction;

[0021] S4: Cool to 120-140℃, add glycidyl methacrylate, then add 0.1-0.3% of boron trifluoride diethyl ether complex as an epoxy ring-opening catalyst, and simultaneously introduce oxygen at a flow rate of 0.1-0.3 L / min·kg base oil, and continue the reaction for 2-3 hours.

[0022] S5: Cool down again to 80-100℃, add 0.5-1.0 parts of benzoyl peroxide as an initiator, and stir to dissolve; add N-vinylpyrrolidone in 3 batches, with an interval of 20 minutes between each batch. After each batch is added, apply nitrogen pressure of 0.2-0.3MPa to inhibit monomer volatilization and maintain for 10 minutes; the initiator initiates the polymerization grafting of the double bond of N-vinylpyrrolidone with the residual active sites on the base oil molecular chain, and the reaction takes 1-2 hours;

[0023] S6: After the reaction is complete, remove low-boiling substances at 120-140℃ and vacuum degree of -0.09 to -0.1MPa, filter through a 3-5μm filter element, and filter pressure ≤0.3MPa to obtain modified base oil.

[0024] Preferably, the power density of the ultrasonic wave in S3 is 0.5-1.5W / cm², and it is turned on for 5 minutes every 15 minutes.

[0025] Preferably, the oxygen in S4 is dried by molecular sieve before being introduced, and the moisture content is ≤10ppm.

[0026] Preferably, after each batch of N-vinylpyrrolidone is added in S5, a nitrogen pressure of 1-2 MPa is immediately applied and maintained for 10 minutes.

[0027] Preferably, after filtration in step S6, the modified base oil is further subjected to a strong magnetic field treatment with a magnetic field strength of 0.5-1.5T for 30-60 minutes.

[0028] (iii) Beneficial technical effects

[0029] Compared with existing technologies, the beneficial effects of this invention are:

[0030] 1. By grafting modification of siloxane group, epoxy group and pyrrolidone group, the base oil molecules form a three-dimensional network with polar adsorption and steric hindrance effect, which improves the viscosity index and enhances the high temperature and high shear viscosity, effectively improving the film forming stability of engine oil under extreme working conditions. The complex antioxidant system formed by the grafting functional group and borate ester, arylamine additive improves the oxidation stability, prolongs the traditional formula, and greatly reduces the aging rate of oil products.

[0031] 2. The nanoscale graphene quantum dots are uniformly dispersed in the oil, forming a nanometer lubricating film, reducing the wear scar diameter and significantly reducing the engine friction loss; the low volatility and high polarity of the ionic liquid suppress the foam generation to less than 10 ml, while reducing the evaporation loss of the oil product. The preparation process of the modified base oil improves the reaction efficiency while reducing energy consumption through ultrasonic strengthening and segmented temperature control, and the production cost is lower than that of hydrogenation process. This scheme realizes the organic unity of high performance, long service life and low environmental impact, and provides a new path for the upgrading of gasoline engine oil technology. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is the base oil molecule modification method flow chart of the gasoline engine oil composition disclosed by the present application;

[0033] Figure 2 is the kinematic viscosity and high temperature and high shear viscosity fold line comparison chart of the examples and comparative examples;

[0034] Figure 3 is the deposit weight and acid value growth comparison chart of the examples and comparative examples;

[0035] Figure 4 is the radar comparison chart of the performance data of the examples and comparative examples after the same dimension. DETAILED DESCRIPTION

[0036] According to Figures 1 to 4 , the specific embodiments of the present application are as follows:

[0037] Example 1

[0038] The present embodiment provides a base oil molecule modification method of a gasoline engine oil composition, which comprises the following treatment steps:

[0039] Dehydration treatment: 1000g API Group III base oil (viscosity index 130, 100℃ kinematic viscosity 6.5mm² / s) is added to a four-necked flask with stirrer, thermometer and condenser, heated to 110℃, and dehydrated under-0.09MPa vacuum for 1.5 hours. The water content after dehydration is 20ppm.

[0040] Silane grafting reaction was carried out: cooling to 70℃, nitrogen was introduced to replace air for 30 minutes, then 45g 3-mercaptopropyltrimethoxysilane was added, and was pre-dehydrated at 45℃, -0.09MPa vacuum for 1 hour; after adding, nitrogen was continued to be introduced for 10 minutes, and the system water content was detected as 35ppm; then it was slowly heated to 165℃. 3.2g dibutyltin dilaurate catalyst (pre-diluted with 15g base oil) was added, and the ultrasonic generator (frequency 30kHz, power density 1.0W / cm²) was turned on for 5 minutes every 15 minutes, and the temperature was maintained for 5 hours.

[0041] Epoxy group grafting reaction was carried out: cooling to 130℃, 35g glycidyl methacrylate was added, then 0.5g boron trifluoride etherate complex was added as catalyst, and dry oxygen (moisture content 8ppm) was introduced at a flow rate of 0.2L / min, and the reaction was carried out for 2.5 hours.

[0042] Pyrrolidone group grafting reaction was carried out: cooling to 90℃, 0.2g dibenzoyl peroxide dissolved in base oil was added, and stirred for 5 minutes; 20g N-vinyl pyrrolidone was added in 3 batches, with an interval of 20 minutes between each batch, and nitrogen pressure of 0.25MPa was applied immediately after each addition and maintained for 10 minutes, and the reaction was continued for 1.5 hours.

[0043] Product post-treatment: heating to 130℃, removing low-boiling substances under vacuum of -0.095MPa for 1 hour, then filtering through a 4μm filter core (filtration pressure 0.2MPa), and finally treating with a 1.0T strong magnetic field for 45 minutes to obtain modified base oil A.

[0044] The present embodiment provides a preparation method of a gasoline engine oil composition, which comprises the following treatment steps:

[0045] The following components were weighed in parts by weight:

[0046] Modified base oil A: 80 parts; borate ashless dispersant (polyisobutylene-based succinimide borate, number average molecular weight 2000, boron content 1.6wt%): 7 parts; zinc dialkyldithiophosphate (ZDDP): 4.5 parts; aromatic amine antioxidant (octylated diphenylamine: N-phenyl-α-naphthylamine = 2:1, containing 1.0wt% nanometer cerium dioxide): 3.5 parts; methacrylate viscosity index improver: 6 parts; benzotriazole derivative metal deactivator: 1 part; graphene quantum dot additive (particle size 5nm, hydroxyl and carboxyl functional group content 15%): 1.2 parts; ionic liquid additive (1-butyl-3-methylimidazolium hexafluorophosphate, purity 99.2%, moisture content 0.04%): 1.8 parts;

[0047] The above components were mixed at 60°C for 2 hours, and then degassed at a vacuum degree of -0.09 MPa for 30 minutes to obtain a gasoline engine oil composition S1.

[0048] Example 2

[0049] The present example provides a method for modifying the molecules of a base oil of a gasoline engine oil composition, comprising the following processing steps:

[0050] Dehydration treatment was performed: 1000 g of API Group III base oil (viscosity index 125, 100°C kinematic viscosity 5.8 mm² / s) was added to a reaction device, and the temperature was raised to 105°C, and the dehydration was performed at a vacuum degree of -0.085 MPa for 2 hours. After dehydration, the water content was 18 ppm.

[0051] Silane grafting reaction was performed: the temperature was lowered to 65°C, and nitrogen was introduced to replace air 3 times, and after each replacement, the nitrogen overpressure was maintained at 0.02-0.03 MPa; 38 g of 3-mercaptopropyltrimethoxysilane was added, and was previously dehydrated at 40-50°C, -0.09 MPa vacuum for 1 hour, and the water content was controlled to be ≤0.02%; nitrogen was continuously introduced for 30 minutes, and the water content of the system was 40 ppm; the temperature was raised to 155°C. 2.8 g of dibutyltin dilaurate catalyst was added, and ultrasonic waves (frequency 25 kHz, power density 0.8 W / cm²) were turned on for 5 minutes every 15 minutes, and the reaction was performed for 6 hours.

[0052] Epoxy group grafting reaction was performed: the temperature was lowered to 125°C, 28 g of glycidyl methacrylate was added, and then 0.1-0.3% of boron trifluoride etherate complex based on the total mass of the system was added as an epoxy ring-opening catalyst, dry oxygen (flow rate 0.15 L / min, water content 5 ppm) was introduced, and the reaction was performed for 3 hours.

[0053] Pyrrolidone group grafting reaction was performed: the temperature was lowered to 85°C, 0.15 g of dibenzoyl peroxide was added as an initiator, and was stirred and dissolved; 15 g of N-vinyl pyrrolidone was added in 3 batches, with an interval of 25 minutes between each batch, and each time the pressure was maintained at 0.2 MPa nitrogen pressure for 10 minutes, and the reaction was performed for 2 hours.

[0054] Product post-treatment: low-boiling substances were removed at 125°C, -0.09 MPa for 1.5 hours, filtered through a 3 μm filter element (pressure 0.25 MPa), treated in a 0.8T strong magnetic field for 50 minutes, and modified base oil B was obtained.

[0055] The present example provides a method for preparing a gasoline engine oil composition, comprising the following processing steps:

[0056] The following components were weighed in parts by weight:

[0057] Modified base oil B: 75 parts; borate ashless dispersant (number average molecular weight 1800, boron content 1.4wt%): 8 parts; ZDDP: 5 parts; aromatic amine antioxidant (containing 0.8wt% nanometer cerium dioxide): 4 parts; viscosity index improver: 7 parts; metal deactivator: 0.8 parts; graphene quantum dot additive (particle size 3nm, functional group content 12%): 0.8 parts; ionic liquid additive: 2.4 parts;

[0058] Stirring at 55℃ for 2.5 hours, degassing for 40 minutes, to obtain gasoline engine oil composition S2.

[0059] Example 3

[0060] The present example provides a base oil molecule modification method of a gasoline engine oil composition, comprising the following processing steps:

[0061] Dehydration treatment: 1000g API Group III base oil (viscosity index 135, 100℃ kinematic viscosity 7.2mm² / s) is heated to 115℃, and dehydrated under a vacuum degree of -0.095MPa for 1 hour, and the water content is reduced to 25ppm.

[0062] Silane grafting reaction: cool to 75℃, replace air with nitrogen for 3 times; add 52g 3-mercaptopropyltrimethoxysilane, which is pre-dehydrated at 40-50℃ under a vacuum of -0.09MPa for 1 hour, and control the water content to be ≤0.02%; continue to pass nitrogen for 30 minutes, and detect the water content of the system to be ≤50ppm; then heat to 175℃. Add 4.0g dibutyltin dilaurate catalyst, and open the ultrasonic wave (frequency 35kHz, power density 1.2W / cm²) for 5 minutes every 15 minutes, and react for 4 hours.

[0063] Epoxy grafting reaction: cool to 135℃, add 42g glycidyl methacrylate, and then add 0.1-0.3% of boron trifluoride etherate complex of the total mass of the system as an epoxy ring-opening catalyst, and pass dry oxygen (flow rate 0.25L / min, water content 10ppm), and react for 2 hours.

[0064] Pyrrolidone grafting reaction: cool to 95℃, add 0.25g dibenzoyl peroxide as an initiator, and stir to dissolve; add 25g N-vinyl pyrrolidone in 3 batches, with an interval of 15 minutes each time, and pressurize 0.3MPa nitrogen pressure to suppress monomer volatilization for 8 minutes each time, and react for 1 hour.

[0065] Product post-treatment: remove low-boiling substances at 135℃ under a vacuum of -0.1MPa for 0.5 hours, filter through a 5μm filter core (pressure 0.15MPa), and treat in a 1.2T strong magnetic field for 35 minutes, to obtain modified base oil C.

[0066] The present embodiment provides a preparation method of a gasoline engine oil composition, comprising the following treatment steps:

[0067] The following components are weighed by parts by weight:

[0068] Modified base oil C: 82 parts; borate ashless dispersant (number average molecular weight 2500, boron content 1.8wt%): 6 parts; ZDDP: 3.8 parts; aromatic amine antioxidant (containing 1.2wt% nanometer cerium dioxide): 3 parts; viscosity index improver: 5 parts; metal deactivator: 1.2 parts; graphene quantum dot additive (particle size 7nm, functional group content 18%): 1.5 parts; ionic liquid additive: 1.5 parts;

[0069] Stirring and mixing at 65°C for 1.5 hours, degassing for 25 minutes, to obtain gasoline engine oil composition S3.

[0070] Comparative Example

[0071] Base oil treatment method

[0072] 1000g of the same API Group III base oil (viscosity index 130, 100°C kinematic viscosity 6.5mm² / s) is dehydrated at 110°C, -0.09MPa for 1.5 hours without graft modification treatment, and is recorded as base oil D.

[0073] Preparation of gasoline engine oil composition

[0074] The following components are weighed by parts by weight:

[0075] Base oil D: 80 parts; conventional polyisobutylene-based succinimide dispersant: 7 parts; ZDDP: 4.5 parts; diphenylamine antioxidant: 3.5 parts; viscosity index improver: 6 parts; metal deactivator: 1 part

[0076] Stirring and mixing at 60°C for 2 hours, degassing for 30 minutes, to obtain gasoline engine oil composition D1.

[0077] The performance results of the examples and comparative examples are as follows:

[0078] Table 1

[0079] Test item Example 1 Example 2 Example 3 Comparative example Kinematic viscosity (100°C, mm2 / s) 11.8 10.9 12.3 11.5 Viscosity index 185 180 190 165 High temperature high shear viscosity (150°C, mPa-s) 3.5 3.3 3.6 3.0 Pour point (°C) -39 -37 -38 -35 Foaminess (ml / ml) 10 / 0 15 / 0 5 / 0 45 / 10 Oxidation stability (TOST lifetime, h) >5000 4800 >5000 2200 Wear scar diameter (mm) 0.42 0.45 0.40 0.65 Deposit weight (mg) 8 10 7 25 Acid value increase (mg KOH / g) 0.8 1.0 0.7 3.2

[0080] As can be seen from the test results, the gasoline engine oil compositions of Examples 1-3 are significantly superior to the comparative example in viscosity index, high temperature stability, anti-wear performance and oxidation stability, proving the synergistic effect of the molecularly modified base oil and the additive formulation of the present application.

[0081] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely exemplary of the principles and application of the present application. Numerous modifications and adaptions can be effected without departing from the spirit and scope of the present application, which is not limited to the exact construction and arrangement described. It is intended, therefore, to cover all modifications and adaptions that fall within the scope of the claims and their equivalents.

Claims

1. A gasoline engine oil composition characterized in that, It is composed of the following components by weight: 70-85 parts of a molecularly modified base oil, 5-10 parts of a borate ashless dispersant, 3-6 parts of zinc dialkyldithiophosphate, 2-5 parts of an aromatic amine antioxidant, 4-8 parts of a methacrylate viscosity index improver, and 0.5-1.5 parts of a benzotriazole derivative metal deactivator; The molecularly modified base oil is prepared by mixing the base oil with 3-mercaptopropyltrimethoxysilane, heating to 150-180°C under nitrogen protection, adding dibutyltin dilaurate catalyst for reaction, then adding glycidyl methacrylate, continuing to react, and finally adding N-vinylpyrrolidone for reaction at 80-100°C to obtain a modified base oil with siloxane groups, epoxy groups, and pyrrolidone groups grafted on the molecular chain; the chemical equation of the reaction is as follows: ； It also includes 0.5-2 parts of graphene quantum dot additives with a particle size of 2-8 nm and containing hydroxyl and carboxyl functional groups on the surface, which are uniformly dispersed in the base oil by ultrasonic dispersion method; It also includes 1-3 parts of ionic liquid additives, which are 1-butyl-3-methylimidazolium hexafluorophosphate with a purity of ≥99% and a water content of ≤0.05%.

2. The gasoline engine oil composition according to claim 1, characterized in that, The borate ashless dispersant is polyisobutenyl succinimide borate with a number average molecular weight of 1000-3000 and a boron content of 1.2-2.0 wt%.

3. The gasoline engine oil composition according to claim 1, characterized in that, The aromatic amine antioxidant is a complex of octylated diphenylamine and N-phenyl-α-naphthylamine with a mass ratio of 2:1 and containing 0.5-1.5 wt% of nano cerium dioxide synergist.

4. A method for producing a molecularly modified base oil of the gasoline engine oil composition according to claim 1, characterized by, The method comprises the following steps: S1: heat the base oil to 100-120°C, and dehydrate under a vacuum degree of -0.08 to -0.1 MPa for 1-2 hours; S2: cool to 60-80°C, replace the air with nitrogen, then add 3-mercaptopropyltrimethoxysilane, and heat to 150-180°C; the 3-mercaptopropyltrimethoxysilane needs to be pre-treated by vacuum dehydration, and the total water content of the system after adding the 3-mercaptopropyltrimethoxysilane needs to be controlled to ≤50 ppm; S3: add dibutyltin dilaurate catalyst, maintain the temperature for 4-6 hours, and apply ultrasonic waves of 20-40 kHz during the reaction; S4: cool to 120-140°C, add glycidyl methacrylate, then add 0.1-0.3% of boron trifluoride etherate complex based on the total mass of the system as an epoxy ring-opening catalyst, and simultaneously introduce oxygen with a flow rate of 0.1-0.3 L / min·kg base oil, and continue to react for 2-3 hours; S5: cool to 80-100°C again, add 0.5-1.0 parts of dibenzoyl peroxide as an initiator, and stir and dissolve; add N-vinylpyrrolidone in 3 batches with an interval of 20 minutes, and apply nitrogen pressure of 0.2-0.3 MPa after each batch to inhibit monomer volatilization for 10 minutes; the initiator initiates the polymerization and grafting of the double bonds of N-vinylpyrrolidone with the residual active sites on the molecular chain of the base oil, and the reaction is carried out for 1-2 hours; S6: After the reaction is completed, low-boiling substances are removed at 120-140℃ under a vacuum of -0.09 to -0.1 MPa, filtered through a filter core with a pore size of 3-5 μm at a filtration pressure of ≤0.3 MPa, to obtain the modified base oil.

5. The method of producing a molecularly modified base oil for a gasoline engine oil composition according to claim 4, characterized in that, The power density of the ultrasonic waves in S3 is 0.5-1.5 W / cm², and the ultrasonic waves are turned on for 5 minutes every 15 minutes.

6. The method for producing a molecularly modified base oil of a gasoline engine oil composition according to claim 4, characterized by, The oxygen in S4 is dried by molecular sieves before being introduced, and the water content is ≤10 ppm.

7. The method of producing a molecularly modified base oil for a gasoline engine oil composition according to claim 4, characterized by, In S5, 1-2 MPa of nitrogen pressure is applied immediately after each batch of N-vinylpyrrolidone is added, and the pressure is maintained for 10 minutes.

8. The method for producing a molecularly modified base oil of a gasoline engine oil composition according to claim 4, characterized by, In S6, after filtration, the modified base oil is further subjected to a step of treatment in a strong magnetic field, with a magnetic field strength of 0.5-1.5 T and a treatment time of 30-60 minutes.

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