A grease for automotive electric window regulators and its preparation method

Abstract

This invention discloses a lubricating grease for automotive electric window regulators and its preparation method. By mass fraction, it comprises the following components: 54%-63% polyalphaolefin synthetic oil, 6%-7% silicone oil, 10%-13% thickener, 15%-23% solid lubricant, 1%-1.5% rust inhibitor, 1%-2% antioxidant, and 1%-1.8% polymer; wherein the weight ratio of polyalphaolefin synthetic oil to silicone oil is 9:1; and the viscosity of the silicone oil at 25°C is within 100 mmHg. 2 / s-750mm 2 / s; the viscosity range of polyalphaolefin synthetic oil at 100℃ is 4mm. 2 / s-10mm 2 / s; The thickener is lithium stearate, produced by reacting fatty acids with an aqueous solution of lithium hydroxide. This invention uses silicone oil and PAO oil together as base oils. After thickening the base oils with a thickener, a high-lubricity solid lubricant is added to develop a grease with excellent low-temperature performance, excellent lubricity, excellent low odor, and excellent dust resistance. It is suitable for lubricating the friction pairs of electric window lift guide rails, wire ropes, pulleys, and winding reels, meeting the product requirements of window lifters.

Description

Technical Field

[0001] This invention relates to the field of lubricating grease technology, and in particular to a lubricating grease for automotive electric window regulators and its preparation method. Background Technology

[0002] An electric window regulator is an electrical mechanism that ensures the smooth raising and lowering of car door windows and allows the glass to remain in any position without bouncing up and down due to external forces or vehicle vibrations. It is mainly divided into single-rail regulators, double-rail regulators, and door-panel regulators.

[0003] Electric window regulators are mainly composed of a motor, reel, reel seat, wire rope, sleeve, guide rail, glass bracket, rotating wheel, bracket, pin shaft, and other parts. The motor drives the reel to rotate, and the wire rope is wound up and unwound around the reel, while simultaneously pulling the glass bracket up and down along the guide rail, thereby realizing the raising and lowering of the car door glass.

[0004] The lubrication points of an electric window regulator are: the rotating wheel rotates along the pin shaft, the wire rope slides along the rotating wheel, the winding wheel rotates in the winding wheel seat, the glass bracket slides along the guide rail, and the wire rope slides along the sleeve.

[0005] The following problems may occur during the use of electric window regulators in automobiles: ① Prolonged operation at low temperatures (-40℃) or inability to raise or lower windows at low temperatures; ② Excessive operating noise or jamming after a period of operation; ③ Slow raising and lowering speed after a period of operation; ④ A foul grease odor emitted at high temperatures (90℃).

[0006] To avoid the aforementioned problems, different greases are typically used between the various friction pairs of the window regulator to reduce or eliminate these issues. In the prior art, a grease product suitable for all friction pairs of electric window regulators is described in patent application number CN201210394911.8, entitled "A Grease Composition and Preparation Method for Automotive Window Regulators." This grease is prepared by adding thickeners and other additives (antioxidants, rust removers, and tackifiers) to a conventional base oil to obtain a grease applicable to the window regulator.

[0007] However, the patent only describes the various test indicators of the grease, without specifying whether it can pass the window regulator's test experiments. In particular, it cannot confirm whether the grease is suitable for durability, noise, and odor tests of the window regulator assembly. Currently, the glass weight, motor selection, number of friction pairs, and overall mechanism efficiency of window regulators vary across different vehicle models, requiring greases with excellent lubricity. The aforementioned patent does not demonstrate the grease's lubrication effect. Furthermore, this patent document describes the need for dust testing of the window regulator, but the dust-resistant effect of the grease described in the aforementioned patent is not mentioned. Additionally, the window regulator requires low-temperature durability testing, which the aforementioned patent does not describe. Therefore, it is necessary to provide a grease that can be applied between all friction pairs in the window regulator assembly, ensuring good lubrication between different friction pairs while also possessing good dust resistance, low-temperature performance, and odor control. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a lubricating grease for automotive electric window regulators and its preparation method. This lubricating grease has the characteristics of excellent lubricity, low odor, low temperature performance, and dust resistance. It is suitable for lubricating all friction pairs of electric window regulators and meets the product usage requirements of window regulators.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: a lubricating grease for automotive electric window regulators, comprising, by mass fraction, the following components: 54%-63% polyalphaolefin synthetic oil, 6%-7% silicone oil, 10%-13% thickener, 15%-23% solid lubricant, 1%-1.5% rust inhibitor, 1%-2% antioxidant, and 1%-1.8% polymer; wherein the weight ratio of polyalphaolefin synthetic oil to silicone oil is 9:1; and the viscosity range of the silicone oil at 25°C is within 100 mm. 2 / s-750mm 2 / s; the viscosity range of polyalphaolefin synthetic oil at 100℃ is 4mm. 2 / s-10mm 2 / s; The thickener is a fatty acid salt produced by reacting fatty acids with an aqueous solution of alkali.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] 1. This invention is the first to use silicone oil and PAO oil together as base oils. After thickening the base oils with a thickener, a high-lubricity solid lubricant is added to develop a grease with excellent low-temperature performance, excellent lubricity, excellent dust resistance, and excellent low odor. It is suitable for lubricating all friction pairs of electric window regulators and meets the needs of window regulator products.

[0012] 2. Based on the low-temperature performance and lubrication properties of the target grease, this invention selects the most suitable ratio of polyalphaolefin synthetic oil and silicone oil for mixing, and requires that the viscosity of the polyalphaolefin synthetic oil (PAO oil) at 100°C be less than 4 mm. 2 / s-10mm 2 The viscosity of silicone oil at 25°C changes within / s to 100 mm². 2 / s-750mm 2 The change within / s enables the grease using the proportions of this invention to have excellent low-temperature performance, low low-temperature starting torque, and low low-temperature steel-to-plastic friction coefficient, ensuring that the window regulator using the grease of this application can start smoothly even at low temperatures; at the same time, the use of a small amount of silicone oil and PAO oil improves the lubrication effect of the prepared grease, making the prepared grease have a better lubrication effect than a single type of base oil, suitable for friction between plastic parts, friction between plastic parts and metal parts, and further for lubrication between all friction pairs in the window regulator assembly, ensuring that the window regulator assembly using the grease of this invention can pass the high and low temperature durability test.

[0013] 3. The grease of the present invention contains both silicone oil and polya-olefin, which has the advantages of better low temperature performance (enhanced by silicone oil) compared to separate components. The silicone oil content is small and is added during the soaping process. At the same time, a large amount of solid lubricant is added, which improves the lubricity. The solid lubricant also plays a part in thickening, so the overall grease is easier to thicken, thus obtaining a grease with good high-temperature performance, low-temperature performance and lubrication effect.

[0014] 4. The difference between the extended working cone penetration and the working cone penetration of the grease of the present invention is smaller than that of the prior art (patent application number CN201210394911.8), indicating that the grease of the present invention has better shear resistance and is less prone to leakage and failure between friction pairs. Combined with the base oil composition of the grease of the present invention, the grease of the present invention has better dust resistance and can successfully pass the dust test of the window regulator.

[0015] 5. The grease of the present invention also has the advantage of low odor under high temperature conditions. According to the test, the odor of the grease of the present invention is 2.5 level under high temperature (65°C) environment, which can effectively avoid the problem of bad odor emitted by the lifting device under high temperature during use.

[0016] Furthermore, the silicone oil includes either dimethyl silicone oil or benzyl silicone oil.

[0017] Furthermore, the polyalphaolefin synthetic oil includes any one of PAO4, PAO6, PAO8, and PAO10.

[0018] Furthermore, the solid lubricant contains two types: PTFE and MCA, with a weight ratio of PTFE to MCA of 9:1.

[0019] Furthermore, the rust inhibitor includes calcium dinonylnaphthalene sulfonate; the fatty acid includes stearic acid; and the base includes lithium hydroxide.

[0020] Furthermore, the polymer includes styrene-ethylene-butene polymers.

[0021] Furthermore, the antioxidants include 2,6-di-tert-butyl-p-cresol.

[0022] The present invention also provides a method for preparing a lubricating grease, comprising the following steps:

[0023] S1: Weigh the raw materials according to the weight percentage of the above-mentioned lubricating grease raw materials and set aside;

[0024] S2: Add alkali, hydrate, and water to the reaction vessel in a preset ratio, heat and mix until the alkali is completely dissolved to obtain an alkali solution;

[0025] S3: Add 80% of the polyalphaolefin synthetic oil, fatty acids, and polymer from step S1 to the alkaline solution in step S2 for saponification reaction.

[0026] S4: After the saponification in step S3 is completed, add the silicone oil from step S1, then heat to 200-205℃ and hold the temperature for a preset time. Then add the remaining 20% ​​of the polyalphaolefin synthetic oil to the reactor and cool to 180-190℃ and hold the temperature for 25-30 minutes.

[0027] S5: After the constant temperature in step S4 is completed, cool down to 110-120℃, add antioxidant and mix evenly, then cool down to 100-110℃ for homogenization.

[0028] S6: After further cooling the product from step S5 to 90-100℃, add rust inhibitor and solid lubricant, stir evenly, filter, degas, and fill to obtain the finished grease.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The biggest difference between the preparation method provided by this invention and the prior art lies in the order of addition of the base oil.

[0031] In existing technologies, the preparation process of lubricating grease involves mixing a portion of the base oil and thickener for a saponification reaction, then adding the remaining base oil and subjecting it to rapid cooling. Other additives (rust inhibitors, antioxidants, etc.) are then added and the mixture is homogenized. This is because existing technologies use one type of base oil or multiple base oils with good compatibility, and mixing these base oils does not result in stratification. Therefore, the traditional production steps for preparing lubricating grease using base oils can be directly followed.

[0032] However, in this application, the base oil contains both silicone oil and polyalphaolefin (PAO) synthetic oil. Silicone oil and PAO synthetic oil cannot be directly mixed because they are immiscible and will separate into layers after standing. Therefore, the preparation process of this invention changes the order of base oil addition based on existing grease preparation processes. During the preparation process, silicone oil is added before the heating stage after saponification. When the remaining PAO synthetic oil is rapidly cooled after addition, soap fibers grow, simultaneously thickening both the silicone oil and the PAO oil. This prevents the grease prepared by this method from separating into layers, and the oil separation rate at high temperatures is also satisfactory.

[0033] Furthermore, in step S6, the filter is made using a 100-mesh filter for 120-150 minutes. Detailed Implementation

[0034] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0035] In this invention, to reduce or avoid the problem of unpleasant odor emitted by the grease at high temperatures, lithium stearate is used as the thickener, which is a fatty acid salt obtained by reacting stearic acid and lithium hydroxide. The use of this thickener effectively reduces the problem of unpleasant odor emitted by the grease at high temperatures. Therefore, the thickeners involved in this embodiment are all lithium stearate. Furthermore, during the grease preparation process, the mass ratio of lithium hydroxide to stearic acid is 28:175.

[0036] Example 1

[0037] This invention provides a lubricating grease, comprising the following components by mass fraction:

[0038]

[0039] Dimethyl silicone oil, viscosity 100 mm at 25°C 2 / s; PAO6, viscosity at 100℃ is 6mm. 2 / s.

[0040] The preparation process of the above-mentioned grease is as follows:

[0041] S1: Weigh the raw materials according to the weight percentage of each ingredient in the grease in the table above, and set aside for later use;

[0042] S2: Add lithium hydroxide and water to the reaction vessel at a weight ratio of 1:4.9, heat to 80-90°C, and mix until the alkali is completely dissolved to obtain a lithium hydroxide solution;

[0043] S3: Add 80% of the PAO6 oil, stearic acid, and polymer from step S1 to the lithium hydroxide solution from step S2, stir and melt at 85-90℃, gradually increase the temperature to carry out the saponification reaction (acid and base mixing at 100℃, saponification reaction at 100-110℃) for 110-120 minutes and drain the water.

[0044] S4: After the saponification in step S3 is completed, keep the temperature at 140℃ for 50 minutes. After confirming that the free shear is qualified, add the dimethyl silicone oil from step S1, then raise the temperature to 200℃ and keep it at 200℃ for 3 minutes. Then add the remaining 20% ​​of PAO6 oil to the reactor and lower the temperature to 180℃ and keep it at 180℃ for 25 minutes.

[0045] S5: After the constant temperature in step S4 is completed, cool down to 110℃, add antioxidant and mix evenly, then cool down to 100℃ for homogenization.

[0046] S6: After further cooling the product from step S5 to 90°C, add rust inhibitor and solid lubricant, stir evenly, filter through a 100-mesh filter for 120 minutes, degas, and then fill to obtain grease 1. Of course, according to usage requirements, other additives can be added after filtration, stirred evenly, then degassed and filled.

[0047] Example 2

[0048] This invention provides a lubricating grease, comprising the following components by mass fraction:

[0049]

[0050] Ethyl silicone oil, viscosity 300 mm at 25°C 2 / s; PAO8, viscosity at 100℃ is 8mm. 2 / s.

[0051] The preparation process of the above-mentioned grease is as follows:

[0052] S1: Weigh the raw materials according to the weight percentage of each ingredient in the grease in the table above, and set aside for later use;

[0053] S2: Add lithium hydroxide and water to the reaction vessel at a weight ratio of 1:4.9, heat to 80-90℃, and mix until the alkali is completely dissolved to obtain a lithium hydroxide solution;

[0054] S3: Add 80% of the PAO8 oil, stearic acid, and polymer from step S1 to the lithium hydroxide solution from step S2, stir and melt at 85-90℃, gradually increase the temperature to carry out the saponification reaction (acid and base mixing at 100℃, saponification reaction at 100-110℃) for 110-120 minutes and drain the water.

[0055] S4: After the saponification in step S3 is completed, keep the temperature at 140℃ for 50 minutes. After confirming that the free shear is qualified, add the benzyl silicone oil from step S1, then raise the temperature to 205℃ and keep it at 205℃ for 3 minutes. Then add the remaining 20% ​​of PAO8 oil to the reactor and lower the temperature to 185℃ and keep it at 185℃ for 25 minutes.

[0056] S5: After the constant temperature in step S4 is completed, cool down to 115℃, add antioxidant and mix evenly, then cool down to 105℃ for homogenization.

[0057] S6: After further cooling the product from step S5 to 95°C, add rust inhibitor and solid lubricant, stir evenly, filter through a 100-mesh filter for 130 minutes, degas, and then fill to obtain grease 2.

[0058] Example 3

[0059] This invention provides a lubricating grease, comprising the following components by mass fraction:

[0060]

[0061] Dimethyl silicone oil, viscosity 500 mm at 25°C 2 / s; PAO4, viscosity at 100℃ is 4mm. 2 / s.

[0062] The preparation process of the above-mentioned grease is as follows:

[0063] S1: Weigh the raw materials according to the weight percentage of each ingredient in the grease in the table above, and set aside for later use;

[0064] S2: Add lithium hydroxide and water to the reaction vessel at a weight ratio of 1:4.9, heat to 80-90℃, and mix until the alkali is completely dissolved to obtain a lithium hydroxide solution;

[0065] S3: Add 80% of the PAO4 oil, stearic acid, and polymer from step S1 to the lithium hydroxide solution from step S2, stir and melt at 85-90℃, gradually increase the temperature to carry out the saponification reaction (acid and base mixing at 100℃, saponification reaction at 100-110℃) for 110-120 minutes and drain the water.

[0066] S4: After the saponification in step S3 is completed, keep the temperature at 140℃ for 50 minutes. After confirming that the free shear is qualified, add the dimethyl silicone oil from step S1, then raise the temperature to 200℃ and keep it at 200℃ for 3 minutes. Then add the remaining 20% ​​of PAO4 oil to the reactor and lower the temperature to 180℃ and keep it at 180℃ for 30 minutes.

[0067] S5: After the constant temperature in step S4 is completed, cool down to 120°C, add antioxidant and mix evenly (stir for 30 minutes), then cool down to 110°C for homogenization.

[0068] S6: After further cooling the product from step S5 to 100°C, add rust inhibitor and solid lubricant, stir evenly (stir for 20 min), filter with a 100-mesh filter for 120 min, degas, and then fill to obtain grease 3.

[0069] Example 4

[0070] This invention provides a lubricating grease, comprising the following components by mass fraction:

[0071]

[0072] Benzyl silicone oil has a kinematic viscosity of 750 mmHg at 25°C. 2 / s; PAO8, kinematic viscosity at 100℃ is 8 mm. 2 / s.

[0073] The preparation process of the above-mentioned grease is as follows:

[0074] S1: Weigh the raw materials according to the weight percentage of each ingredient in the grease in the table above, and set aside for later use;

[0075] S2: Add lithium hydroxide and water to the reaction vessel at a weight ratio of 1:4.9, heat to 80-90℃, and mix until the alkali is completely dissolved to obtain a lithium hydroxide solution;

[0076] S3: Add 80% of the PAO8 oil, stearic acid, and polymer from step S1 to the lithium hydroxide solution from step S2, stir and melt at 85-90℃, gradually increase the temperature to carry out the saponification reaction (acid and base mixing at 100℃, saponification reaction at 100-110℃) for 110-120 minutes and drain the water.

[0077] S4: After the saponification in step S3 is completed, keep the temperature at 140℃ for 50 minutes. After confirming that the free shear is qualified, add the benzyl silicone oil from step S1, then raise the temperature to 200℃ and keep it at 200℃ for 3 minutes. Then add the remaining 20% ​​of PAO8 oil to the reactor and lower the temperature to 190℃ and keep it at 190℃ for 28 minutes.

[0078] S5: After the constant temperature in step S4 is completed, cool down to 110℃, add antioxidant and mix evenly, then cool down to 100℃ for homogenization.

[0079] S6: After further cooling the product from step S5 to 90°C, add rust inhibitor and solid lubricant, stir evenly, filter through a 100-mesh filter for 120 minutes, degas, and then fill to obtain finished grease 4.

[0080] Example 5

[0081] This invention provides a lubricating grease, comprising the following components by mass fraction:

[0082]

[0083] Dimethyl silicone oil, kinematic viscosity at 25°C is 500 mm. 2 / s; The kinematic viscosity of PAO4 at 100℃ is 4 mm² / s; 2 / s.

[0084] The preparation process of the above-mentioned grease is as follows:

[0085] S1: Weigh the raw materials according to the weight percentage of each ingredient in the grease in the table above, and set aside for later use;

[0086] S2: Add lithium hydroxide and water to the reaction vessel at a weight ratio of 1:4.9, heat to 80-90℃, and mix until the alkali is completely dissolved to obtain a lithium hydroxide solution;

[0087] S3: Add 80% of the PAO4 oil, stearic acid, and polymer from step S1 to the lithium hydroxide solution from step S2, stir and melt at 85-90℃, gradually increase the temperature to carry out the saponification reaction (acid and base mixing at 100℃, saponification reaction at 100-110℃) for 110-120 minutes and drain the water.

[0088] S4: After the saponification in step S3 is completed, keep the temperature at 140℃ for 50 minutes. After confirming that the free shear is qualified, add the dimethyl silicone oil from step S1, then raise the temperature to 200℃ and keep it at 200℃ for 3 minutes. Then add the remaining 20% ​​of PAO4 oil to the reactor and lower the temperature to 180℃ and keep it at 180℃ for 30 minutes.

[0089] S5: After the constant temperature in step S4 is completed, cool down to 120℃, add antioxidant and mix evenly, then cool down to 110℃ for homogenization.

[0090] S6: After further cooling the product from step S5 to 100°C, add rust inhibitor and solid lubricant, stir evenly, filter through a 100-mesh filter for 120 minutes, degas, and then fill to obtain finished grease 5.

[0091] Example 6

[0092] This invention provides a lubricating grease, comprising the following components by mass fraction:

[0093]

[0094] Benzyl silicone oil, kinematic viscosity at 25°C is 500 mmHg. 2 / s; PAO8, kinematic viscosity at 100℃ is 8 mm. 2 / s.

[0095] The preparation process of the above-mentioned grease is as follows:

[0096] S1: Weigh the raw materials according to the weight percentage of each ingredient in the grease in the table above, and set aside for later use;

[0097] S2: Add lithium hydroxide and water to the reaction vessel at a weight ratio of 1:4.9, heat to 80-90℃, and mix until the alkali is completely dissolved to obtain a lithium hydroxide solution;

[0098] S3: Add 80% of the PAO8 oil, stearic acid, and polymer from step S1 to the lithium hydroxide solution from step S2, stir and melt at 85-90℃, gradually increase the temperature to carry out the saponification reaction (acid and base mixing at 100℃, saponification reaction at 100-110℃) for 110-120 minutes and drain the water.

[0099] S4: After the saponification in step S3 is completed, keep the temperature at 140℃ for 50 minutes. After confirming that the free shear is qualified, add the benzyl silicone oil from step S1, then raise the temperature to 200℃ and keep it at 200℃ for 3 minutes. Then add the remaining 20% ​​of PAO8 to the reactor and lower the temperature to 190℃ and keep it at 190℃ for 25 minutes.

[0100] S5: After the constant temperature in step S4 is completed, cool down to 110℃, add antioxidant and mix evenly, then cool down to 100℃ for homogenization.

[0101] S6: After further cooling the product from step S5 to 90°C, add rust inhibitor and solid lubricant, stir evenly, filter through a 100-mesh filter for 120 minutes, degas, and then fill to obtain the finished lubricating grease 6.

[0102] Example 7

[0103] This invention provides a lubricating grease, comprising the following components by mass fraction:

[0104]

[0105] Dimethyl silicone oil, kinematic viscosity at 25°C is 750 mmHg. 2 / s; PAO6, kinematic viscosity at 100℃ is 6mm. 2 / s.

[0106] The preparation process of the above-mentioned grease is as follows:

[0107] S1: Weigh the raw materials according to the weight percentage of each ingredient in the grease in the table above, and set aside for later use;

[0108] S2: Add lithium hydroxide and water to the reaction vessel at a weight ratio of 1:4.9, heat to 80-90℃, and mix until the alkali is completely dissolved to obtain a lithium hydroxide solution;

[0109] S3: Add 80% of the PAO6 oil, stearic acid, and polymer from step S1 to the lithium hydroxide solution from step S2, stir and melt at 85-90℃, gradually increase the temperature to carry out the saponification reaction (acid and base mixing at 100℃, saponification reaction at 100-110℃) for 110-120 minutes and drain the water.

[0110] S4: After the saponification in step S3 is completed, keep the temperature at 140℃ for 50 minutes. After confirming that the free shear is qualified, add the dimethyl silicone oil from step S1, then raise the temperature to 200℃ and keep it at 200℃ for 3 minutes. Then add the remaining 20% ​​of PAO6 oil to the reactor and lower the temperature to 190℃ and keep it at 190℃ for 30 minutes.

[0111] S5: After the constant temperature in step S4 is completed, cool down to 120℃, add antioxidant and mix evenly, then cool down to 110℃ for homogenization.

[0112] S6: After further cooling the product from step S5 to 100°C, add rust inhibitor and solid lubricant, stir evenly, filter through a 100-mesh filter for 150 minutes, degas, and then fill to obtain the finished lubricating grease 7.

[0113] Example 8

[0114] This invention provides a lubricating grease, comprising the following components by mass fraction:

[0115]

[0116] Methylphenyl silicone oil, methyl silicone oil, and ethyl silicone oil all have a kinematic viscosity of 500 mmHg at 25°C. 2 / s; The kinematic viscosity of PAO10 at 100℃ is 10 mm³ / s; 2 / s.

[0117] The preparation process of the above-mentioned grease is as follows:

[0118] S1: Weigh the raw materials according to the weight percentage of each ingredient in the grease in the table above, and set aside for later use;

[0119] S2: Add lithium hydroxide and water to the reaction vessel at a weight ratio of 1:4.9, heat to 80-90℃, and mix until the alkali is completely dissolved to obtain a lithium hydroxide solution;

[0120] S3: Add 80% of the PAO10 oil, stearic acid, and polymer from step S1 to the lithium hydroxide solution from step S2, stir and melt at 85-90℃, gradually increase the temperature to carry out the saponification reaction (acid and base mixing at 100℃, saponification reaction at 100-110℃) for 110-120 minutes and drain the water.

[0121] S4: After the saponification in step S3 is completed, keep the temperature at 140℃ for 50 minutes. After confirming that the free shear is qualified, add the benzyl silicone oil from step S1, then raise the temperature to 200℃ and keep it at 200℃ for 3 minutes. Then add the remaining 20% ​​of PAO10 oil to the reactor and lower the temperature to 180℃ and keep it at 180℃ for 25 minutes.

[0122] S5: After the constant temperature in step S4 is completed, cool down to 120℃, add antioxidant and mix evenly, then cool down to 110℃ for homogenization.

[0123] S6: After further cooling the product from step S5 to 100°C, add rust inhibitor and solid lubricant, stir evenly, filter through a 100-mesh filter for 120 minutes, degas, and then fill to obtain finished grease 8.

[0124] Comparative Example 1

[0125] To verify the effect of PAO oils of different viscosities on the overall performance of the grease, this example, based on Example 3, only changed the viscosity of the PAO oil while keeping other conditions unchanged, and obtained the comparative greases No. 1-3 in Table 1.

[0126] Compare the grease grades PAO oil type and viscosity in raw materials No. 1 <![CDATA[PAO10, the kinematic viscosity at 100 °C is 10 mm 2 / s]]> No. 2 <![CDATA[The kinematic viscosity of PAO25 at 100 °C is 25.1 mm 2 / s]]> No. 3 <![CDATA[The kinematic viscosity of PAO40 at 100 °C is 39 mm 2 / s]]>

[0127] Table 1

[0128] Comparative Example 2

[0129] To verify the effect of silicone oils of different viscosities on the overall performance of the grease, this embodiment, based on Example 3, only changed the viscosity of the silicone oil while keeping other conditions unchanged, and obtained the comparative greases No. 4-6 in Table 2.

[0130] Compare the grease grades Silicone oil type and viscosity in raw materials No. 4 <![CDATA[Dimethyl silicone oil, with a kinematic viscosity of 750 mm 2 / s at 25°C]]> No. 5 <![CDATA[Dimethyl silicone oil, with a kinematic viscosity of 1000 mm 2 / s at 25°C]]> No. 6 <![CDATA[Dimethyl silicone oil, kinematic viscosity at 25°C is 900mm 2 / s]]>

[0131] Table 2

[0132] Comparative Example 3

[0133] To verify the effect of different proportions of PAO oil and silicone oil in the base oil on the overall performance of the grease, this example, based on Example 3, only changed the ratio of methyl silicone oil and PAO4 oil, while keeping other adjustments unchanged, to obtain the comparative greases No. 7-10 in Table 3.

[0134] Compare the grease grades The weight ratio of dimethyl silicone oil to PAO4 oil in the raw materials No. 7 5:5 No. 8 3:7 No. 9 2:8 No. 10 1:10

[0135] Table 3

[0136] Comparative Example 4

[0137] The difference between this embodiment and embodiment 3 is as follows:

[0138] In the preparation of the grease, dimethyl silicone oil, PAO4 oil, and stearic acid were added together to the heated alkaline solution, while other steps remained unchanged, to obtain No. 11 comparative grease.

[0139] Comparative Example 5

[0140] The difference between this embodiment and comparative embodiment 3 is as follows:

[0141] In the preparation of the grease, dimethyl silicone oil and the remaining 20% ​​of PAO4 oil were used together to cool the product after saponification and heating. Other steps remained unchanged, resulting in No. 12 comparative grease.

[0142] Comparative Example 6

[0143] The difference between this embodiment and Comparative Example 3 is that the solid lubricant in this embodiment is PTFE particles (polytetrafluoroethylene particles with a particle size of 200 mesh). Using the preparation method in Example 3, Comparative Lubricating Oil No. 13 was obtained.

[0144] Comparative Example 7

[0145] The difference between this embodiment and Comparative Embodiment 3 is that the solid lubricant in the grease formulation is MCA.

[0146] Using the preparation method in Example 3, Comparative Lubricating Oil No. 14 was obtained.

[0147] Lubricating oil performance testing

[0148] Effect Experiment:

[0149] The performance of the 8 lubricating greases obtained in Examples 1-8 was analyzed.

[0150]

[0151] Table 4

[0152] The data recorded in Table 4 shows that:

[0153] Regarding odor, all eight greases tested in Table 4 had the advantage of low odor under high-temperature conditions.

[0154] As can be seen from the friction performance, the friction coefficients of the eight greases in Table 4 are all relatively small. This is because the solid lubricant of the present invention uses a combination of PTFE particles and MCA. Adding a mixed solid lubricant to the grease can improve the friction effect between plastics or between plastics and metals, making the lubrication effect of the grease of the present invention better.

[0155] The data on low-temperature aerodynamic torque and low-temperature motion torque show that all eight greases in Table 4 have good low-temperature performance, enabling the elevator to start smoothly even in low-temperature environments.

[0156] The data from the steel mesh shows that even when this product uses a mixture of silicone oil and PAO oil as the base oil, the resulting grease will not separate. This is because the present invention has improved the silicone oil addition step in the preparation process. The silicone oil is added during the heating stage after saponification. After rapid cooling, the soap fibers grow, which can thicken both the silicone oil and PAO oil at the same time, so the grease will not separate. The oil separation rate can also meet the requirements at high temperatures.

[0157] As can be seen from the data on working cone penetration and extended working cone penetration in Table 4, the grease has relatively high hardness. Therefore, this type of grease has high viscosity at low temperatures. Even when operating at low temperatures, it can maintain a stable lubrication effect and is not prone to leakage or failure.

[0158] In summary, it can be seen that the grease provided in this application has good performance, possessing excellent low-temperature performance, excellent lubricity, and excellent low odor. Furthermore, the data for grease 3 (the product prepared in Example 3) in Table 4 are particularly superior; the parameters of the grease in this formulation are better than those of the greases in other examples.

[0159] Comparative Experiment 1

[0160] The performance parameters of 14 comparative products (Comparative Examples 1-7) were tested and compared with the data of grease 3.

[0161] The data in Table 5.

[0162]

[0163]

[0164] Table 5

[0165] Comparative Experiment 2:

[0166] To further verify the difference between the parameters of the grease in this product and existing greases, MULTEMP TAS NO.2 grease from Synergy Oil & Grease Lubrication Engineering (Shanghai) Co., Ltd. was purchased as Comparative Example 1; and the grease test data recorded in the patent technology (patent application number CN201210394911.8) was used as Comparative Example 2, and compared with the test data of grease 3 prepared in Example 3 of this invention, the data in Table 6 were obtained.

[0167]

[0168] Table 6

[0169] Combining the data in Tables 5 and 6, and comparing the test data of grease 3 and comparative greases 1-3, it can be seen that the data in comparative grease 1 are quite similar to those in grease 3. However, as the viscosity of the PAO base oil increases, the low-temperature performance of the prepared greases (comparative greases 2 and 3) deteriorates. Therefore, even when using a mixture of PAO base oil and silicone oil as the base oil for the entire grease, PAO oil with an unsuitable viscosity range should not be arbitrarily selected. Therefore, combining the data in Tables 4 and 5, it can be seen that the PAO oil provided in this invention has a viscosity range of 4-10 mm at 100℃. 2 The ratio of / s is maintained to ensure that the grease prepared according to this invention has better overall performance.

[0170] The test data of grease 3 and comparative greases 4-6 show that the data of comparative grease 4 is similar to that of grease 3, but the overall performance of grease 4 is lower than that of grease 3. In particular, as the viscosity of dimethyl silicone oil increases, the lubricating effect of the grease increases. However, because higher viscosity dimethyl silicone oil is less likely to thicken, the cone penetration increases, and the low-temperature performance also slightly deteriorates. Therefore, the proportion of grease separated by the stencil is higher in comparative greases 4-6. This indicates that to ensure smooth thickening of dimethyl silicone oil without adding thickener, one cannot simply pursue high viscosity dimethyl silicone oil. Therefore, the silicone oil used in this application has a viscosity range of 100-750 mmHg at 25°C. 2 / s.

[0171] The test data from grease 3 and comparative greases 7-10 show that the lubrication performance, high-temperature performance, and low-temperature performance of greases 7-8 are inferior to those of grease 3. Clearly, a higher proportion of silicone oil in the base oil is not necessarily better. Comparing the data of grease 10 with those of grease 3 reveals insufficient lubrication, increased low-temperature torque, and a higher coefficient of friction. Therefore, it can be shown that the proportion of silicone oil in the base oil needs to be selected in conjunction with the performance of other components (especially solid lubricants), and cannot be arbitrarily chosen. Based on this, the present invention selects a silicone oil to PAO oil mass ratio of 1:9 as the base oil for the entire grease.

[0172] The test data for greases 3, 11, and 12, as shown by the oil separation data from the stencil, reveal that the order in which silicone oil is added during the preparation process is crucial. Different addition points directly affect whether the silicone oil can thicken together with the PAO oil. Incorrect addition order leads to oil separation in the prepared grease, resulting in poor overall performance. Therefore, when using a mixture of PAO oil and silicone oil as the base oil for the grease, the silicone oil must be added during the heating stage after saponification. This ensures that after the remaining PAO oil is added and rapidly cooled, soap fibers grow, simultaneously thickening both the silicone oil and PAO oil, thus ensuring the stability of the prepared grease and meeting application requirements.

[0173] Based on the test data of grease 3 and comparative greases 13 and 14, it can be seen that changing the type of solid lubricant has a relatively large impact on the coefficient of friction of the grease. Using a single solid lubricant as an additive in the entire grease is not as effective as using a mixture of PTFE particles and MCA. Therefore, in order to make the grease suitable for all friction pairs of the lifting device, grease 3 is more suitable than comparative greases 13 and 14 and has a better lubrication effect.

[0174] Combining the test data from Comparative Examples 1-2 and Lubricant 3, it can be seen that the friction coefficient, low-temperature starting torque, and low-temperature operating torque of Comparative Example 1 are all significantly higher than those of Lubricant 3, indicating that the lubricating properties and low-temperature performance of the lubricating oil in Comparative Example 1 are inferior to those of Lubricant 3. Furthermore, odor testing reveals that the product in Comparative Example 1 releases a pungent odor at high temperatures, indicating that this grease does not meet the requirement of low odor at high temperatures. In Comparative Example 2, the loading data in the patent document shows that the low-temperature performance of the lubricating oil is also lower than that of this product, and it cannot be verified whether the patented product can meet the low-odor requirement at high temperatures. Additionally, this product exhibits greater oil separation on the steel mesh, resulting in lower stability in use compared to Lubricant 3. In summary, the grease prepared by this invention has advantages over existing technologies, including low odor at high temperatures, good low-temperature performance, and superior lubrication effect.

[0175] Window regulator assembly testing compliance experiment

[0176] Durability tests were conducted on the glass lifter assembly using eight greases from Examples 1-8 of this invention, 14 comparative greases from Comparative Examples 1-7, and the externally sourced grease from Comparative Example 1. Among glass lifters, the double-track glass lifter, due to its complex structure, lower mechanism efficiency, and heavier glass load, requires the highest performance grease; therefore, the double-track glass lifter assembly test was the most representative. The durability test of the double-track glass lifter assembly required 7500 cycles at 80°C (Experiment 1), 3000 cycles at -30°C (Experiment 2), 16500 cycles at 20°C under ash spraying conditions (Experiment 3), and 3000 cycles at 55°C and 95% RH humidity (Experiment 4), totaling 30,000 cycles. The test results of the above 23 products are as follows:

[0177] As shown in Table 7.

[0178]

[0179]

[0180] Table 7

[0181] Experiment 1: 80℃ × 7500 cycles. This experiment can be demonstrated by combining the dropping point, evaporation loss, and oil separation on the stencil; since the grease did not show signs of drying due to large loss or evaporation of base oil at high temperatures, the impact on the lubrication effect of the grease is relatively low.

[0182] As can be seen from the test results of the above 23 products recorded in Table 7, the comparative greases 7, 8, 9, 11, and 12 and Comparative Example 1 failed Experiment 1.

[0183] The fact that greases 7-9 failed Experiment 1 indicates that a higher proportion of silicone oil in the base oil is not necessarily better. This is because silicone oil is not easily thickened, and a higher proportion of silicone oil in the base oil results in a smaller cone penetration. After 100,000 shear cycles, the extended cone penetration is even smaller. Therefore, greases 7-8 failed the test in Experiment 1. However, greases 1-8 of the present invention, as shown in Table 7, all passed the test in Experiment 1, indicating that the proportion of silicone oil in the entire base oil should not be too high. Therefore, the base oil of the grease should be selected with a silicone oil to PAO oil mass ratio of 1:9 as described in the present invention.

[0184] The fact that greases 11 and 12 failed Experiment 1 indicates that even when silicone oil and PAO oil are used as the base oil in a 1:9 mass ratio, the order in which the silicone oil is added directly affects the high-temperature performance of the prepared grease. Combined with the fact that grease 3 passed Experiment 1 in Table 7, this demonstrates that the silicone oil must be added during the heating stage after saponification. This ensures that after the remaining PAO oil is added and rapidly cooled, soap fibers grow, simultaneously thickening both the silicone oil and PAO oil. This prevents the prepared grease from separating and ensures it meets the required high-temperature performance.

[0185] Experiment 2: -30℃ × 3000 cycles. Whether this experiment can be validated by combining low-temperature torque data with lubricating grease data is crucial; a lower low-temperature torque indicates that the elevator can start smoothly at low temperatures.

[0186] As can be seen from the test results of the above 23 products recorded in Table 7, comparative greases 2, 3, and 10 and comparative example 1 failed experiment 2.

[0187] Comparing greases 2 and 3, which failed Experiment 2, it was found that the higher the viscosity of PAO oil at 100℃, the worse the low-temperature performance of the grease, and the smooth start-up of the lifting device in low-temperature environments could not be guaranteed. Therefore, only PAO oil with a viscosity range of 4-10 mm at 100℃ was selected. 2 / s of PAO oil.

[0188] The fact that grease 10 failed Experiment 2 indicates that when the proportion of silicone oil in the base oil is too low, the resulting grease will have insufficient lubricity, increased low-temperature torque, and a higher coefficient of friction. Therefore, the proportion of silicone oil in the base oil should not be too low. Combining the experimental results of greases 7-9 in Table 7, it can be shown that using a silicone oil to PAO oil mass ratio of 1:9 as the base oil for the entire grease results in the best lubrication and low-temperature performance.

[0189] Experiment 3: At 20℃, grease was sprayed 16,500 times. This experiment determined whether the grease passed the test and could be combined with the frictional properties of the lubricating grease. A low coefficient of friction ensures continuous and efficient lubrication of the lifting device, and the extended working cone penetration was used to assess the grease's shear resistance. Furthermore, grease spraying did not affect durability, indicating strong grease resistance.

[0190] As can be seen from the test results of the above 23 products recorded in Table 7, greases 5, 6, 13, and 14, as well as Comparative Example 1, failed Experiment 3.

[0191] Compared to greases 5 and 6, which failed Experiment 2, the data in Table 5 shows that although greases 5 and 6 have a better coefficient of friction than grease 3, they also have a greater extended working cone penetration. This indicates that even though using silicone oil with higher viscosity can improve the overall lubrication effect of the grease, it also affects the shear resistance of the grease. This shows that as the viscosity of dimethyl silicone oil increases, the lubrication effect of the grease increases. However, since dimethyl silicone oil with higher viscosity is less likely to thicken, the cone penetration becomes larger and larger, and the extended cone penetration also increases accordingly, which is not conducive to the shear resistance of the grease.

[0192] The failure of greases 13 and 14 in Experiment 2 indicates that the composition of solid lubricants also affects the lubrication performance of greases. Using a single solid lubricant as an additive in the entire grease is not as effective as using a mixture of PTFE particles and MCA. Therefore, in order to make the grease suitable for all friction pairs of the lifting device, grease 3 is more suitable than greases 13 and 14 and has a better lubrication effect.

[0193] Experiment 4: 55℃, 95% humidity, 3000 cycles. This experiment was used to determine whether the grease could withstand corrosion by a copper plate. The metal parts of the window regulator did not show any rust (humidity can cause metal to rust), indicating that the grease has excellent rust prevention capabilities.

[0194] As can be seen from the test results of the above 23 products recorded in Table 7, all of the greases passed the test of Experiment 4, indicating that the above 23 greases have good metal protection capabilities.

[0195] The data in Table 7 shows that all eight greases prepared in Examples 1-8, as well as comparative greases 1 and 4, passed the durability test of the dual-track lift assembly, indicating that all ten greases possess good anti-dust properties. Combined with the performance test data of the ten greases recorded in Tables 4 and 5, this demonstrates that the grease formulation and preparation method provided by this invention are applicable to all friction pairs in dual-track lifts, ensuring the low-temperature and high-temperature performance of the lift, and ensuring that this product can be applied to glass lifts.

[0196] In summary, it can be seen that the present invention has the following advantages:

[0197] 1. This invention is the first to use silicone oil and PAO oil together as base oils. After thickening the base oils with a thickener, a high-lubricity solid lubricant is added to develop a grease with excellent low-temperature performance, excellent lubricity, excellent dust resistance, and excellent low odor. It is suitable for lubricating all friction pairs of electric window regulators and meets the needs of window regulator products.

[0198] 2. Based on the low-temperature performance and lubrication properties of the target grease, this invention selects the most suitable ratio of polyalphaolefin synthetic oil and silicone oil for mixing, and requires that the viscosity of the polyalphaolefin synthetic oil (PAO oil) at 100°C be less than 4 mm. 2 / s-10mm 2 The viscosity of silicone oil at 25°C changes within / s to 100 mm². 2 / s-750mm 2 The change within / s enables the grease using the proportions of this invention to have excellent low-temperature performance (low starting torque at low temperatures, low coefficient of friction between steel and plastic at low temperatures), ensuring that the window regulator using the grease of this application can start smoothly even at low temperatures; at the same time, by mixing a small amount of silicone oil with PAO oil (the mass ratio of silicone oil to PAO oil is 1:9), the lubrication effect of the prepared grease is improved, making the prepared grease have a better lubrication effect than a single type of base oil (low coefficient of friction between steel and plastic at room temperature), suitable for friction between plastic parts, friction between plastic parts and metal parts, and further for lubrication between all friction pairs in the window regulator assembly, ensuring that the window regulator assembly using the grease of this invention can pass the high and low temperature durability test.

[0199] 3. The grease of the present invention contains both silicone oil and polya-olefin, which has the advantage of better low temperature performance (enhanced by silicone oil) compared to the two separate components. The silicone oil content is small and is added during the soaping process. At the same time, a large amount of solid lubricant is added, which improves the lubricity and also plays a part in thickening. Therefore, the overall grease is easier to thicken, resulting in a grease with good high-temperature performance, low-temperature performance and lubrication effect.

[0200] 4. The difference between the extended working cone penetration and the working cone penetration of the grease of the present invention is smaller than that of the prior art (patent application number CN201210394911.8), indicating that the grease of the present invention has better shear resistance and is less prone to loss and failure between friction pairs. Combined with the base oil composition and oil film thickness data of the grease of the present invention, there is a thicker oil film between friction pairs, which makes the grease of the present invention have better dust resistance.

[0201] 5. The grease of the present invention also has the advantage of low odor under high temperature conditions. According to the test, the odor of the grease of the present invention is 2.5 level under high temperature (65°C) environment, which can effectively avoid the problem of bad odor emitted by the lifting device under high temperature during use.

[0202] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for preparing a lubricating grease for automotive electric window regulators, characterized in that: Includes the following steps: S1: Weigh the raw materials according to the weight percentage and set aside; S2: Add alkali and water to the reaction vessel according to the preset ratio, heat and mix until the alkali is completely dissolved to obtain an alkali solution; S3: Add 80% of the polyalphaolefin synthetic oil, fatty acids, and polymer from step S1 to the alkaline solution in step S2 for saponification reaction. S4: After the saponification in step S3 is completed, add the silicone oil from step S1, then heat to 200-205℃ and hold the temperature for a preset time. Then add the remaining 20% ​​of the polyalphaolefin synthetic oil to the reactor and cool to 180-190℃ and hold the temperature for 25-30 minutes. S5: After the constant temperature in step S4 is completed, cool down to 110-120℃, add antioxidant and mix evenly, then cool down to 100-110℃ for homogenization. S6: After further cooling the product from step S5 to 90-100℃, add rust inhibitor and solid lubricant, stir evenly, filter, degas, and fill to obtain the finished grease. The grease for automotive power window regulators, by mass fraction, comprises the following components: The composition includes: 54%-63% polyalphaolefin synthetic oil, 6%-7% silicone oil, 10%-13% thickener, 15%-23% solid lubricant, 1%-1.5% rust inhibitor, 1%-2% antioxidant, and 1%-1.8% polymer. The weight ratio of polyalphaolefin synthetic oil to silicone oil is 9:1; the viscosity range of the silicone oil at 25°C is within 100 mm. 2 / s-750mm 2 / s; the viscosity range of polyalphaolefin synthetic oil at 100℃ is 4mm. 2 / s-10mm 2 / s; The thickener is a fatty acid salt produced by reacting fatty acids with an aqueous solution of alkali; Solid lubricants include two types: PTFE and MCA, with a weight ratio of 9:1 for PTFE and MCA.

2. The preparation method according to claim 1, characterized in that: Silicone oil includes either benzyl silicone oil or dimethyl silicone oil.

3. The preparation method according to claim 1 or 2, characterized in that: Polyalphaolefin synthetic oils include any one of PAO4, PAO6, PAO8, and PAO10.

4. The preparation method according to claim 1 or 2, characterized in that: Rust inhibitors include calcium dinonylnaphthalene sulfonate; fatty acids include stearic acid; and bases include lithium hydroxide.

5. The preparation method according to claim 1 or 2, characterized in that: The polymers include styrene-ethylene-butene polymers.

6. The preparation method according to claim 1 or 2, characterized in that: Antioxidants include 2,6-di-tert-butyl-p-cresol.

7. The preparation method according to claim 1 or 2, characterized in that: In step S5, filter the filter using a 100-mesh screen for 120-150 minutes.

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