A lubricating oil composition and a method for producing the same

Abstract

The application belongs to the technical field of lubricating oil, and particularly relates to a lubricating oil composition and a preparation method thereof. The lubricating oil composition comprises linear siloxane, organically modified polysiloxane and pentaerythritol ester. The application has the following beneficial effects: the linear siloxane and the organically modified polysiloxane in the lubricating oil composition have low low-temperature viscosity, and have strong compatibility and can be mutually soluble with the pentaerythritol ester to improve the characteristics of large viscosity at low temperature; the mixed lubricating system obtained by the preparation method has the characteristics of simple mixing mode, excellent uniformity, large mixable amount and the like, and is suitable for industrial production.

Description

Technical Field

[0001] This invention belongs to the field of lubricating oil technology, specifically relating to a lubricating oil composition and its preparation method. Background Technology

[0002] Lubricating oil effectively lubricates components such as bearings and transmission gears that frequently experience friction and wear, and removes heat absorbed by these components, thus maintaining stable engine operation. Polar navigation is accompanied by harsh conditions such as low temperatures and sea conditions. Low-temperature applications also exist in high-altitude, extremely cold regions. For example, in the Arctic winter season, temperatures range from -43 to -26°C, with an average temperature of -34°C; in high-altitude, frigid regions such as Tibet and Qinghai, temperatures above 4000 meters can reach -10°C. These conditions place even higher demands on the application of lubricating oil at low temperatures.

[0003] The viscosity of lubricating oil is one of the most important physical properties affecting heat and mass transfer, and it is a crucial characteristic for determining the oil film thickness on the bearing surface and the elastohydrodynamic lubrication pressure and temperature conditions. Furthermore, viscosity is also a significant factor affecting the fatigue life of bearings and gears. For most lubricants, viscosity increases at low temperatures (<-10℃), increasing the torque required to start machinery or equipment, and reducing fluidity, leading to insufficient lubrication and increased friction and wear. To improve the low-temperature viscosity of lubricating oil, researchers have added antifreeze and additives to reduce its viscosity at low temperatures. However, because the lubricating properties of additives differ from those of lubricating oils, their wear resistance and anti-wear properties are weakened.

[0004] Pentaerythritol ester (PAG or Ester) is a synthetic base oil with excellent thermal oxidation stability and low volatility at high temperatures. Its viscosity-temperature characteristics are as follows: at high temperatures, it maintains low viscosity change, providing a stable lubricating film; while at lower temperatures, the viscosity does not become excessively high, ensuring fluid flow and good starting performance. These characteristics make pentaerythritol ester popular in many demanding industrial applications, such as aerospace, turbines, and high-temperature environments. However, pentaerythritol ester (3,5,5-trimethylacetic acid) has a viscosity of 10 mPas@100s at 0°C. -1 Furthermore, its viscosity decreases continuously as the temperature drops, which greatly limits its application in low-temperature start-up and operation.

[0005] Studies have found that adding polyisobutylene copolymers, ethylene propylene copolymers, and polytoluene acrylate copolymers to pentaerythritol ester lubricating oils can adjust their low-temperature viscosity, but it affects their tribological characteristics over a wide temperature range. Therefore, finding a suitable method to solve the problem of poor rheological properties of pentaerythritol ester lubricating oils at low temperatures has great application potential. Summary of the Invention

[0006] This application provides a lubricating oil composition and its preparation method, aiming to solve the problem of poor rheological properties of pentaerythritol ester lubricating oil at low temperatures.

[0007] The first aspect of this application provides a lubricating oil composition comprising linear siloxane, organically modified polysiloxane, and pentaerythritol ester.

[0008] The linear siloxane and organically modified polysiloxane in the lubricating oil composition described in this application have low low-temperature viscosity and strong compatibility. They are miscible with pentaerythritol esters, which improves their high viscosity at low temperatures.

[0009] According to some embodiments of the lubricating oil composition described in this application, the linear polysiloxane includes one or more of methyl silicone oil, ethyl silicone oil, dimethyl silicone oil, benzyl silicone oil, and diethyl silicone oil.

[0010] According to some embodiments of the lubricating oil composition described in this application, the linear polysiloxane is one or more of ethyl silicone oil, benzyl silicone oil, and methyl silicone oil.

[0011] According to some embodiments of the lubricating oil composition described in this application, the organic modified polysiloxane includes one or more of chlorophenylsiloxane, methyltetrachlorophenyl silicone oil, hydroxyl fluorosilicone oil, and fluorochlorosilicone oil.

[0012] According to some embodiments of the lubricating oil composition described in this application, the organic modified polysiloxane is one or more of chlorophenylsiloxane, methyltetrachlorophenyl silicone oil, and hydroxyfluorosiloxane.

[0013] According to some embodiments of the lubricating oil composition described in this application, the mass ratio of the linear siloxane, the organic modified polysiloxane, and the pentaerythritol ester is (1-5):(0-3):(0-9).

[0014] According to some embodiments of the lubricating oil composition described in this application, the mass ratio of the linear siloxane, the organic modified polysiloxane, and the pentaerythritol ester is (0.6-1.5):1:(1-1.6).

[0015] According to some embodiments of the lubricating oil composition described in this application, the viscosity of the lubricating oil composition at 0°C is 0.15-0.55 Pa·s.

[0016] A second aspect of this application provides a method for preparing the lubricating oil composition described in the first aspect of this application, comprising the following steps: mixing linear siloxane, organically modified polysiloxane, and pentaerythritol ester to obtain the lubricating oil composition.

[0017] The mixed lubrication system prepared by the method of this application has the characteristics of simple mixing method, excellent uniformity and large mixable amount, and is suitable for industrial production.

[0018] According to some embodiments of the preparation method of the lubricating oil composition described in this application, the mixing temperature is 50-80°C and the mixing time is 10-60 min. Detailed Implementation

[0019] The embodiments of the present invention are described in detail below. These embodiments are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0020] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0021] This application provides a lubricating oil composition comprising a linear siloxane, an organically modified polysiloxane, and a pentaerythritol ester. The linear siloxane and organically modified polysiloxane in the lubricating oil composition of this application have low low-temperature viscosity and strong compatibility, and can be miscible with pentaerythritol ester to improve its high viscosity at low temperatures.

[0022] In some embodiments of this application, the linear polysiloxane includes one or more of methyl silicone oil, ethyl silicone oil, dimethyl silicone oil, benzyl silicone oil, and diethyl silicone oil.

[0023] In some embodiments of this application, the linear polysiloxane is one or more of ethyl silicone oil, benzyl silicone oil, and methyl silicone oil. Ethyl silicone oil has weak intermolecular forces due to the effect of the ethyl group, and is miscible with ester oils and mineral oils. It also has excellent thermal stability, good dielectric properties, hydrophobicity, and low surface tension, and is therefore used as a base oil for polishing agents, magnetorheological agents, and other materials.

[0024] In some embodiments of this application, the organic modified polysiloxane includes one or more of chlorophenylsiloxane, methyltetrachlorophenylsiloxane, hydroxyfluorosiloxane, and fluorochlorosiloxane.

[0025] In some embodiments of this application, the organically modified polysiloxane is one or more of chlorophenylsiloxane, methyltetrachlorophenyl silicone oil, and hydroxyl fluorosiloxane. Chlorophenylsiloxane is produced by introducing polychlorinated benzyl groups into the chemical structure of polysiloxane, resulting in a colorless or pale yellow transparent liquid with physical properties varying with molecular weight. As the phenyl content increases, the density and refractive index increase; the freezing point of low phenyl content is below -70°C; and the thermal stability of medium and high phenyl contents improves, while exhibiting excellent radiation resistance.

[0026] In some embodiments of this application, the mass ratio of the linear siloxane, the organic modified polysiloxane, and the pentaerythritol ester is (1-5):(0-3):(0-9).

[0027] In some embodiments of this application, the mass ratio of the linear siloxane, the organic modified polysiloxane, and the pentaerythritol ester is (0.6-1.5):1:(1-1.6), for example, 0.6:1:1, 0.8:1:1, 1:1:1, 1.2:1:1.2, 1.5:1:1.5, 1.5:1:1.6, etc. The lubricating oil composition obtained from this ratio range has the optimal high-temperature friction coefficient and wear amount on ceramic / steel friction pairs, showing a trend of low-temperature viscosity and high-temperature friction performance consistent with each other, thus constructing a wide-temperature-range lubricating material system.

[0028] In some embodiments of this application, the viscosity of the lubricating oil composition at 0°C is 0.15-0.55 Pa·s, such as 0.15 Pa·s, 0.20 Pa·s, 0.25 Pa·s, 0.30 Pa·s, 0.36 Pa·s, 0.38 Pa·s, 0.43 Pa·s, 0.45 Pa·s, 0.5 Pa·s, 0.52 Pa·s, and 0.55 Pa·s. The low-temperature dynamic viscosity is a key factor affecting the low-temperature starting performance of engine equipment and devices; the lower the low-temperature viscosity, the easier it is to start. The higher the low-temperature viscosity, the greater the difficulty for the engine to operate at low temperatures, and the longer it takes for the lubricating oil to reach the friction points. This can lead to brief periods of dry or semi-liquid friction, increasing wear. The lubricating oil described in this application has a viscosity of 0.15-0.55 Pa·s at 0°C, which is relatively low at low temperatures, thus solving the problem of poor rheological properties of pentaerythritol ester lubricating oil at low temperatures.

[0029] This application also provides a method for preparing the lubricating oil composition described in the first aspect of this application, comprising the following steps: mixing linear siloxane, organic modified polysiloxane and pentaerythritol ester to obtain the lubricating oil composition. The mixed lubrication system obtained by the preparation method of this application has the characteristics of simple mixing method, excellent uniformity and large mixable amount, and is suitable for industrial production.

[0030] In some embodiments of this application, the mixing temperature is 50-80°C, such as 50°C, 60°C, 70°C, 80°C, etc., and the mixing time is 10-60 min, such as 10 min, 20 min, 30 min, 40 min, 50 min, 60 min, etc.

[0031] The technical solution of this application will be further explained below with reference to specific implementation cases.

[0032] Example 1

[0033] A lubricating oil composition comprising 3g ethyl silicone oil, 3g chlorophenyl silicone oil and 3g pentaerythritol ester.

[0034] The method for preparing the lubricating oil composition includes the following steps:

[0035] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0036] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0037] Step 2: Compounding the mixed oil: Weigh 3g of ethyl silicone oil, 3g of chlorophenyl silicone oil and 3g of pentaerythritol ester at a mass ratio of 1:1:1, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0038] Example 2

[0039] The only difference between Example 2 and Example 1 is that the lubricating oil composition described in Example 2 includes 3g of ethyl silicone oil, 2g of chlorophenyl silicone oil and 5g of pentaerythritol ester.

[0040] The specific operating steps include:

[0041] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0042] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0043] Step 2: Compounding the mixed oil: Weigh 3g of ethyl silicone oil, 2g of chlorophenyl silicone oil and 5g of pentaerythritol ester at a mass ratio of 3:2:5, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0044] Example 3

[0045] The only difference between Example 3 and Example 1 is that the lubricating oil composition described in Example 3 includes 3g of ethyl silicone oil, 3g of chlorophenyl silicone oil and 4g of pentaerythritol ester.

[0046] The specific operating steps include:

[0047] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0048] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0049] Step 2: Compounding the mixed oil: Weigh 3g of ethyl silicone oil, 3g of chlorophenyl silicone oil and 4g of pentaerythritol ester in a mass ratio of 3:3:4, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0050] Example 4

[0051] The only difference between Example 4 and Example 1 is that the lubricating oil composition of Example 4 includes 2g of ethyl silicone oil, 3g of chlorophenyl silicone oil and 5g of pentaerythritol ester.

[0052] The specific operating steps include:

[0053] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0054] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0055] Step 2: Compounding the mixed oil: Weigh 2g of ethyl silicone oil, 3g of chlorophenyl silicone oil and 5g of pentaerythritol ester at a mass ratio of 2:3:5, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0056] Example 5

[0057] The only difference between Example 5 and Example 1 is that the lubricating oil composition of Example 5 includes 3g of benzyl silicone oil, 3g of chlorophenyl silicone oil and 3g of pentaerythritol ester.

[0058] The specific operating steps include:

[0059] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0060] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0061] Step 2: Compounding the mixed oil: Weigh 3g of benzyl silicone oil, 4g of chlorophenyl silicone oil and 3g of pentaerythritol ester in a mass ratio of 3:3:3, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0062] Example 6

[0063] The only difference between Example 6 and Example 1 is that the lubricating oil composition of Example 6 includes 3g of ethyl silicone oil, 3g of chlorophenylsiloxane and 3g of pentaerythritol ester.

[0064] The specific operating steps include:

[0065] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0066] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0067] Step 2: Compounding the mixed oil: Weigh 3g of ethyl silicone oil, 3g of chlorophenylsiloxane and 3g of pentaerythritol ester in a mass ratio of 3:3:3, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0068] Example 7

[0069] The only difference between Example 7 and Example 1 is that the lubricating oil composition of Example 7 includes 3g of ethyl silicone oil, 3g of hydroxyl fluorosilicone oil and 3g of pentaerythritol ester.

[0070] The specific operating steps include:

[0071] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0072] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0073] Step 2: Compounding the mixed oil: Weigh 3g of ethyl silicone oil, 3g of hydroxyl fluorosilicone oil and 3g of pentaerythritol ester at a mass ratio of 1:1:1, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0074] Example 8

[0075] The only difference between Example 8 and Example 1 is that the lubricating oil composition of Example 8 includes 3g of ethyl silicone oil, 3g of methyltetrachlorophenyl silicone oil and 3g of pentaerythritol ester.

[0076] The specific operating steps include:

[0077] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0078] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0079] Step 2: Compounding the mixed oil: Weigh 3g of ethyl silicone oil, 3g of methyltetrachlorophenyl silicone oil and 3g of pentaerythritol ester at a mass ratio of 1:1:1, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0080] Example 9

[0081] The only difference between Example 9 and Example 1 is that the lubricating oil composition of Example 9 includes 3g of methyl silicone oil, 3g of ethyl silicone oil and 3g of pentaerythritol ester.

[0082] The specific operating steps include:

[0083] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0084] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0085] Step 2: Compounding the mixed oil: Weigh 3g of methyl silicone oil, 3g of ethyl silicone oil and 3g of pentaerythritol ester at a mass ratio of 1:1:1, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0086] Example 10

[0087] The only difference between Example 10 and Example 1 is that the lubricating oil composition of Example 10 includes 2g of ethyl silicone oil, 2g of chlorophenyl silicone oil and 6g of pentaerythritol ester.

[0088] The specific operating steps include:

[0089] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0090] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0091] Step 2: Compounding the mixed oil: Weigh 2g of ethyl silicone oil, 2g of chlorophenyl silicone oil and 6g of pentaerythritol ester at a mass ratio of 1:1:3, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0092] Example 11

[0093] The only difference between Example 11 and Example 1 is that the lubricating oil composition of Example 11 includes 1g of ethyl silicone oil, 2g of chlorophenyl silicone oil and 7g of pentaerythritol ester.

[0094] The specific operating steps include:

[0095] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0096] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0097] Step 2: Compounding the mixed oil: Weigh 1g of ethyl silicone oil, 2g of chlorophenyl silicone oil and 7g of pentaerythritol ester at a mass ratio of 1:2:7, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0098] Example 12

[0099] The only difference between Example 12 and Example 1 is that the lubricating oil composition of Example 12 includes 1g of ethyl silicone oil, 1g of chlorophenyl silicone oil and 8g of pentaerythritol ester.

[0100] The specific operating steps include:

[0101] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0102] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0103] Step 2: Compounding the mixed oil: Weigh 1g of ethyl silicone oil, 1g of chlorophenyl silicone oil and 8g of pentaerythritol ester at a mass ratio of 1:1:8, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0104] Comparative Example 1

[0105] The only difference between Comparative Example 1 and Example 1 is that the lubricating oil composition of Comparative Example 1 uses ethylene propylene copolymer (OCP) instead of ethyl silicone oil and chlorophenyl silicone oil.

[0106] The specific operating steps include:

[0107] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0108] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0109] Step 2: Compounding the mixed oil: Weigh 6g of ethylene propylene copolymer (OCP) and 3g of pentaerythritol ester at a mass ratio of 2:1, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0110] Comparative Example 2

[0111] The only difference between Comparative Example 2 and Example 1 is that the lubricating oil composition of Comparative Example 2 uses hydrogenated styrene-diene copolymer instead of chlorophenyl silicone oil.

[0112] The specific operating steps include:

[0113] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0114] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0115] Step 2: Compounding the mixed oil: Weigh 3g of ethyl silicone oil, 3g of hydrogenated styrene-diene copolymer and 3g of pentaerythritol ester at a mass ratio of 1:1:1, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0116] Comparative Example 3

[0117] The only difference between Comparative Example 3 and Example 1 is that the lubricating oil composition of Comparative Example 3 uses polymethyl methacrylate instead of ethyl silicone oil.

[0118] The specific operating steps include:

[0119] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0120] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0121] Step 2: Compounding the oil mixture: Weigh 3g of polymethacrylate, 3g of chlorophenyl silicone oil and 3g of pentaerythritol ester at a mass ratio of 1:1:1, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0122] Comparative Example 4

[0123] The only difference between Comparative Example 4 and Example 1 is that the lubricating oil composition of Comparative Example 4 does not contain the raw material chlorophenyl silicone oil.

[0124] The specific operating steps include:

[0125] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0126] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0127] Step 2: Compounding the mixed oil: Weigh 3g of ethyl silicone oil and 3g of pentaerythritol ester at a mass ratio of 1:1, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0128] Comparative Example 5

[0129] The only difference between Comparative Example 5 and Example 1 is that the lubricating oil composition of Comparative Example 5 does not contain the raw materials chlorophenyl silicone oil and ethyl silicone oil.

[0130] Comparative Example 6

[0131] The only difference between Comparative Example 6 and Example 1 is that the lubricating oil composition of Comparative Example 6 does not contain the raw material ethyl silicone oil.

[0132] The specific operating steps include:

[0133] Step 1: Pretreatment: Clean the beaker with deionized water, acetone, and anhydrous ethanol in sequence using ultrasonic cleaning.

[0134] The specific procedure is as follows: first, use deionized water for ultrasonic cleaning for 15 minutes, then use acetone for ultrasonic cleaning for 15 minutes, then use anhydrous ethanol for ultrasonic cleaning for 15 minutes, and then place the beaker in an oven at 60°C to dry for 12 hours for later use.

[0135] Step 2: Compounding the mixed oil: Weigh 3g of chlorophenyl silicone oil and 3g of pentaerythritol ester at a mass ratio of 1:1, with an accuracy of 0.001g. Mix them in the beaker dried in Step 1, sonicate at a frequency of 20kHz for 30 minutes, and then place them in an oil bath at 60℃ for 30 minutes to fully dissolve them, finally obtaining a lubricating oil composition with excellent low-temperature viscosity.

[0136] Viscosity tests of the lubricating oil compositions described in Examples 1-12 and Comparative Examples 1-6 of this application:

[0137] The test method was as follows: the viscosity of the lubricating oil composition was tested using Anton Paar R301.

[0138] The specific operation is as follows: First, install the test rotor on the rheometer, and set the shear rate to 0.001, 0.01, 0.02, 0.05, 0.01... up to 1000s. -1 A total of 400 sampling points were used for the shear rate, with a sampling time of 1 second. Then, low-temperature rheological testing was started, with tests conducted every 5°C. The test temperature range was kept within ±1°C. The test was stopped when the shear rate suddenly increased or changed very little. The test results are shown in Table 1.

[0139] Table 1

[0140] Viscosity at 0℃ Low temperature viscosity Example 1 0.332 Pa·s The low-temperature viscosity at -50℃ is 20.6 Pa·s. Example 2 0.321 Pa·s The low-temperature viscosity at -40℃ is 34.96 Pa.s Example 3 0.333 Pa·s The low-temperature viscosity at -50℃ is 20.8 Pa·s. Example 4 0.157 Pa·s The low-temperature viscosity at -45℃ is 31.33 Pa·s. Example 5 0.166 Pa·s The low-temperature viscosity at -50℃ is 20.94 Pa·s. Example 6 0.298 Pa·s The low-temperature viscosity at -55℃ is 23.4 Pa·s. Example 7 0.2166 Pa·s The low-temperature viscosity at -80℃ is 10.14 Pa·s. Example 8 0.53 Pa·s The low-temperature viscosity at -80℃ is 13.4 Pa·s. Example 9 0.51 Pa·s The low-temperature viscosity at -60℃ is 19.49 Pa·s. Example 10 0.451 Pa·s The low-temperature viscosity at -38℃ is 34.17 Pa·s. Example 11 2.36 Pa·s The low-temperature viscosity at -18℃ is 34.99 Pa·s. Example 12 4.40 Pa·s The low-temperature viscosity at -15℃ is 29.76 Pa.s Comparative Example 1 14.25 Pa·s The low-temperature viscosity at -10℃ is 35.5 Pa·s. Comparative Example 2 12.29 Pa·s The low-temperature viscosity at -5℃ is 30.65 Pa·s. Comparative Example 3 13.26 Pa·s The low-temperature viscosity at -5℃ is 29.92 Pa.s Comparative Example 4 13.06 Pa·s The low-temperature viscosity at -5℃ is 23.11 Pa·s. Comparative Example 5 12.96 Pa·s The low-temperature viscosity at -5℃ is 23.11 Pa. Comparative Example 6 13.56 Pa·s The low-temperature viscosity at -5℃ is 22.62 Pa·s.

[0141] As can be seen from Table 1, organically modified polysiloxanes can effectively improve the viscosity-temperature characteristics of high-viscosity pentaerythritol esters, achieving good flowability at lower temperatures.

[0142] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A lubricating oil composition, characterized in that, Including linear polysiloxanes, organically modified polysiloxanes, and pentaerythritol esters; The linear polysiloxane includes one or more of methyl silicone oil, ethyl silicone oil, and benzyl silicone oil; The organic modified polysiloxane includes one or more of polychlorophenylsiloxane, methyltetrachlorophenylsiloxane, hydroxyl fluorosiloxane, and fluorochlorosiloxane; The mass ratio of the linear polysiloxane, the organic modified polysiloxane, and the pentaerythritol ester is (0.6-1.5):1:(1-1.6).

2. The lubricating oil composition according to claim 1, characterized in that, The organic modified polysiloxane is one or more of polychlorophenylsiloxane, methyltetrachlorophenyl silicone oil, and hydroxyl fluorosiloxane.

3. The lubricating oil composition according to any one of claims 1-2, characterized in that, The viscosity of the lubricating oil composition at 0°C is 0.15-0.55 Pa·s.

4. A method for preparing the lubricating oil composition according to any one of claims 1-3, characterized in that, Includes the following steps: The linear polysiloxane, the organically modified polysiloxane, and the pentaerythritol ester are mixed to obtain the lubricating oil composition. The linear polysiloxane includes one or more of methyl silicone oil, ethyl silicone oil, and benzyl silicone oil; The organic modified polysiloxane includes one or more of polychlorophenylsiloxane, methyltetrachlorophenylsiloxane, hydroxyl fluorosiloxane, and fluorochlorosiloxane.

5. The method for preparing the lubricating oil composition according to claim 4, characterized in that, The mixing temperature is 50-80℃, and the mixing time is 10-60 min.