Automobile Constant Velocity Joint Anti-rust Grease and Its Preparation Method

Abstract

The present invention discloses the composition of an anti-rust grease for automotive constant velocity joints and its preparation method, which relates to the technical field of grease. The grease of the present invention comprises the following raw materials in parts by weight: 65-75 parts of base oil, 0.5-5 parts of thickening agent, 1-5 parts of antioxidant, 0.1-0.5 parts of rust inhibitor, and 0.5-5 parts of extreme pressure and anti-wear agent. The preparation method of the thickening agent comprises the following steps: S1: heating 12-hydroxy stearic acid, sebacic acid, and modified calcium hydroxide for reaction; S2: continuously heating for reaction for a period of time; S3: continuously heating for reaction for a period of time to obtain the thickening agent.

Description

Technical Field

[0001] The present invention relates to the technical field of greases, and particularly to an anti-rust grease for automotive constant velocity joints and a preparation method thereof. Background Art

[0002] Automobile parts generally refer to all parts and components except the vehicle frame. Among them, parts refer to individual components that cannot be disassembled; components refer to combinations of parts that achieve a certain action (or: function). With the steady development of the Chinese economy and the gradual improvement of the living standards of residents, the demand for automobile parts in new vehicle supporting has increased. At the same time, with the continuous increase in the number of motor vehicles in China, the demand for parts in the aftermarket such as automobile maintenance and automobile modification has gradually expanded, and the requirements for various parts have become higher and higher. The Chinese automobile parts industry has achieved good development achievements in recent years.

[0003] An automobile generally consists of four basic parts: an engine, a chassis, a body, and electrical equipment. Therefore, all kinds of subdivided products of automobile parts are derived from these four basic parts. Classified by the nature of the parts, they can be divided into an engine system, a power system, a transmission system, a suspension system, a braking system, an electrical system, and others (general supplies, loading tools, etc.). Among them, key automobile parts such as constant velocity joints of the ball cage type, drive shaft assemblies, hub bearing units, rubber parts, shock absorbers, etc. have special requirements for the use of grease. Summary of the Invention

[0004] The purpose of the present invention is to provide an anti-rust grease for automotive constant velocity joints and a preparation method thereof, and solve the following technical problems:

[0005] The existing grease contains a lithium hydroxide-calcium hydroxide system, and the introduced calcium soap improves the water resistance and extreme pressure anti-wear performance of the grease, but the thickening ability of the thickener decreases.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] An anti-rust grease for automotive constant velocity joints, the grease comprises the following raw materials in parts by weight: 65 - 75 parts of base oil, 0.5 - 5 parts of thickener, 1 - 5 parts of antioxidant, 0.1 - 0.5 parts of rust inhibitor, 0.5 - 5 parts of extreme pressure anti-wear agent.

[0008] As a further scheme of the present invention: the base oil is one or more of naphthenic oil, paraffin-based mineral oil, Fischer-Tropsch synthetic oil, alkylbenzene, and is obtained by mixing in any ratio.

[0009] As a further scheme of the present invention: the antioxidant is any one of N-phenyl-α-naphthylamine and 2,6-di-tert-butyl-p-cresol.

[0010] As a further solution of the present invention: the rust inhibitor is any one of benzotriazole, thiadiazole, barium dinonylnaphthalene sulfonate, alkenyl succinic acid, dodecenyl succinic acid ester, alkenyl succinic acid ester, alkenyl succinic acid ester.

[0011] As a further solution of the present invention: the extreme pressure and anti-wear agent is any one of dialkyldithiocarbamate or dialkyldithiophosphate.

[0012] As a further solution of the present invention: the preparation method of the thickener includes the following steps:

[0013] S1: Mix 12-hydroxystearic acid and sebacic acid, heat up to 85 - 90 °C, add modified calcium hydroxide, keep warm and react for 0.25 - 0.5 h, then heat up to 90 - 100 °C, add lithium hydroxide, and react for 0.5 - 1.5 h;

[0014] S2: Continue to heat up to 140 - 150 °C, and keep warm and react for 0.5 - 1 h under stirring conditions;

[0015] S3: Continue to heat up to 190 - 210 °C, keep warm and react for 0.2 - 0.5 h to obtain the thickener.

[0016] As a further solution of the present invention: the addition ratio of 1,2-hydroxystearic acid, sebacic acid, modified calcium hydroxide, and lithium hydroxide in S1 is 5 - 10:3 - 4:1 - 2:2 - 3.

[0017] As a further solution of the present invention: the preparation method of the modified calcium hydroxide includes the following steps:

[0018] A1: Mix the calcined limestone and distilled water evenly, add propylene glycol under stirring conditions, age for 3 - 6 h, and dry to obtain Component 1;

[0019] A2: Add Component 1, citric acid monohydrate, and deionized water into the reaction kettle, heat up to 40 - 50 °C, keep warm for 3 - 6 h, wash with water and dry to obtain Component 2;

[0020] A3: Add Component 2, N,N'-dicyclohexylcarbodiimide, and absolute ethanol into the reaction kettle, add the aqueous solution of sulfanilic acid, heat up to 50 - 55 °C, keep warm for 3 - 6 h, filter, wash, and dry to obtain the modified calcium hydroxide.

[0021] As a further solution of the present invention: the mass ratio of the calcined limestone: distilled water: propylene glycol in A1 is 10:50 - 100:5 - 10.

[0022] As a further solution of the present invention: the mass ratio of Component 1, citric acid monohydrate, and deionized water in A2 is 5:1 - 3:50 - 100.

[0023] As a further solution of the present invention: In the reaction kettle, add component two in A3, N,N'-dicyclohexylcarbodiimide, and absolute ethanol. The addition ratio of the aqueous solution of sulfanilic acid is 0.3 - 0.5 g : 0.5 - 1 g : 50 - 100 mL : 75 mL. The 75 mL aqueous solution of sulfanilic acid contains 0.3 - 0.5 g of sulfanilic acid.

[0024] The preparation method of the automotive constant velocity joint anti-rust grease comprises the following steps: Add the base oil and the thickening agent into the reaction kettle, heat up to 70 - 90 °C, and then add the antioxidant, the rust inhibitor, and the extreme pressure and anti-wear agent, and grind to obtain the grease.

[0025] The beneficial effects of the present invention:

[0026] The thickening agent prepared in this application can effectively adsorb and fix the base oil to form a grease in the form of a stable system performance pseudo-gel. And the addition of modified calcium hydroxide effectively improves the problem that the thickening ability of the grease is reduced due to the introduction of calcium soap in the grease. The carbon skeleton on the surface of calcium hydroxide cooperates with the other components in the grease, has a compact structure, and is more tightly wound, and can form a denser oil film on the friction surface. The grease obtains a stronger thickening ability, has better mechanical stability performance and higher extreme pressure and anti-wear performance. Specific embodiments

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0028] Example 1

[0029] The preparation method of the modified calcium hydroxide comprises the following steps:

[0030] A1: Mix 50 g of calcined limestone and 250 mL of distilled water evenly, add 25 g of propylene glycol under stirring conditions, age for 3 h, and dry to obtain component one;

[0031] A2: Add 50 g of component one, 10 g of citric acid monohydrate, and 500 mL of deionized water into the reaction kettle, heat up to 40 °C, keep warm for 3 h, wash with water and dry to obtain component two;

[0032] A3: Prepare an aqueous solution of sulfanilic acid: 12 g of sulfanilic acid is contained in 3000 mL of the solution;

[0033] A4: Add 9 g of Component II, 15 g of N,N'-dicyclohexylcarbodiimide, and 1500 mL of absolute ethanol into a reaction kettle, then add 2250 mL of aqueous sulfanilic acid solution. Heat up to 50 - 55 °C and keep the temperature for 3 - 6 h. Filter, wash, and dry to obtain modified calcium hydroxide.

[0034] Example 2

[0035] The preparation method of modified calcium hydroxide comprises the following steps:

[0036] A1: Mix 50 g of calcined limestone and 400 mL of distilled water evenly. Under stirring conditions, add 40 g of propylene glycol, age for 3 h, and dry to obtain Component I;

[0037] A2: Add 50 g of Component I, 20 g of citric acid monohydrate, and 700 mL of deionized water into a reaction kettle. Heat up to 45 °C and keep the temperature for 3 h. Wash with water and dry to obtain Component II;

[0038] A3: Prepare an aqueous sulfanilic acid solution: 12 g of sulfanilic acid is contained in 3000 mL of the solution;

[0039] A4: Add 9 g of Component II, 20 g of N,N'-dicyclohexylcarbodiimide, and 2000 mL of absolute ethanol into a reaction kettle, then add 2250 mL of aqueous sulfanilic acid solution. Heat up to 55 °C and keep the temperature for 3 h. Filter, wash, and dry to obtain modified calcium hydroxide.

[0040] Example 3

[0041] The preparation method of modified calcium hydroxide comprises the following steps:

[0042] A1: Mix 50 g of calcined limestone and 500 mL of distilled water evenly. Under stirring conditions, add 50 g of propylene glycol, age for 6 h, and dry to obtain Component I;

[0043] A2: Add 50 g of Component I, 30 g of citric acid monohydrate, and 1000 mL of deionized water into a reaction kettle. Heat up to 50 °C and keep the temperature for 6 h. Wash with water and dry to obtain Component II;

[0044] A3: Prepare an aqueous sulfanilic acid solution: 12 g of sulfanilic acid is contained in 3000 mL of the solution;

[0045] A4: Add 9 g of Component II, 30 g of N,N'-dicyclohexylcarbodiimide, and 3000 mL of absolute ethanol into a reaction kettle, then add 2250 mL of 0.3 g aqueous sulfanilic acid solution. Heat up to 55 °C and keep the temperature for 6 h. Filter, wash, and dry to obtain modified calcium hydroxide.

[0046] Example 4

[0047] The preparation method of the thickening agent comprises the following steps:

[0048] S1: Mix 5 g of 12 - hydroxy stearic acid and 4 g of sebacic acid, heat up to 90 °C, add 2 g of the modified calcium hydroxide prepared in Example 1, keep warm and react for 0.5 h, then heat up to 100 °C, add 2 g of lithium hydroxide, and react for 1.5 h;

[0049] S2: Continue to heat up to 150 °C, and under the condition of stirring, keep warm and react for 1 h;

[0050] S3: Continue to heat up to 190 °C, keep warm and react for 0.2 h to obtain the thickening agent.

[0051] Example 5

[0052] The preparation method of the thickening agent comprises the following steps:

[0053] S1: Mix 5 g of 12 - hydroxy stearic acid and 4 g of sebacic acid, heat up to 90 °C, add 2 g of the modified calcium hydroxide prepared in Example 2, keep warm and react for 0.5 h, then heat up to 100 °C, add 2 g of lithium hydroxide, and react for 1.5 h;

[0054] S2: Continue to heat up to 150 °C, and under the condition of stirring, keep warm and react for 1 h;

[0055] S3: Continue to heat up to 190 °C, keep warm and react for 0.2 h to obtain the thickening agent.

[0056] Example 6

[0057] The preparation method of the thickening agent comprises the following steps:

[0058] S1: Mix 5 g of 12 - hydroxy stearic acid and 4 g of sebacic acid, heat up to 90 °C, add 2 g of the modified calcium hydroxide prepared in Example 3, keep warm and react for 0.5 h, then heat up to 100 °C, add 2 g of lithium hydroxide, and react for 1.5 h;

[0059] S2: Continue to heat up to 150 °C, and under the condition of stirring, keep warm and react for 1 h;

[0060] S3: Continue to heat up to 190 °C, keep warm and react for 0.2 h to obtain the thickening agent.

[0061] Example 7

[0062] The preparation method of automotive constant velocity joint anti - rust lubricating grease comprises the following steps:

[0063] B1: The lubricating grease comprises the following raw materials in parts by weight: 75 parts of naphthenic oil, 2 parts of the thickening agent prepared in Example 4, 5 parts of N - phenyl - α - naphthylamine, 0.5 part of benzotriazole, and 5 parts of dialkyldithiocarbamate.

[0064] B2: Add naphthenic oil and the thickener prepared in Example 4 into a reaction kettle, heat up to 70 °C, then add N-phenyl-α-naphthylamine, benzotriazole, and dialkyldithiocarbamate, and grind to obtain the grease.

[0065] Example 8

[0066] A method for preparing an automotive constant velocity joint anti-rust grease comprises the following steps:

[0067] B1: The grease comprises the following raw materials in parts by weight: 75 parts of naphthenic oil, 2 parts of the thickener prepared in Example 5, 5 parts of N-phenyl-α-naphthylamine, 0.5 part of benzotriazole, and 5 parts of dialkyldithiocarbamate.

[0068] B2: Add naphthenic oil and the thickener prepared in Example 4 into a reaction kettle, heat up to 70 °C, then add N-phenyl-α-naphthylamine, benzotriazole, and dialkyldithiocarbamate, and grind to obtain the grease.

[0069] Example 9

[0070] A method for preparing an automotive constant velocity joint anti-rust grease comprises the following steps:

[0071] B1: The grease comprises the following raw materials in parts by weight: 75 parts of naphthenic oil, 2 parts of the thickener prepared in Example 6, 5 parts of N-phenyl-α-naphthylamine, 0.5 part of benzotriazole, and 5 parts of dialkyldithiocarbamate.

[0072] B2: Add naphthenic oil and the thickener prepared in Example 4 into a reaction kettle, heat up to 70 °C, then add N-phenyl-α-naphthylamine, benzotriazole, and dialkyldithiocarbamate, and grind to obtain the grease.

[0073] Comparative Example 1

[0074] A method for preparing modified calcium hydroxide comprises the following steps:

[0075] Mix 50 g of calcined limestone and 250 mL of distilled water evenly, add 25 g of propylene glycol under stirring conditions, age for 3 h, and dry to obtain modified calcium hydroxide.

[0076] Comparative Example 2

[0077] A method for preparing modified calcium hydroxide comprises the following steps:

[0078] A1: Mix 50 g of calcined limestone and 250 mL of distilled water evenly, add 25 g of propylene glycol under stirring conditions, age for 3 h, and dry to obtain Component 1;

[0079] A2: Add 50 g of Component 1, 10 g of citric acid monohydrate, and 500 mL of deionized water into a reaction kettle, heat up to 40 °C, keep warm for 3 h, wash with water and dry to obtain modified calcium hydroxide.

[0080] Comparative Example 3

[0081] Compared with Example 4, in Comparative Example 3, only the modified calcium hydroxide prepared in Example 1 added therein was replaced with the modified calcium hydroxide prepared in Comparative Example 1 in equal amount, and the other components were exactly the same as those in Example 4.

[0082] Comparative Example 4

[0083] Compared with Example 4, in Comparative Example 4, only the modified calcium hydroxide prepared in Example 1 added therein was replaced with the modified calcium hydroxide prepared in Comparative Example 2 in equal amount, and the other components were exactly the same as those in Example 4.

[0084] Comparative Example 5

[0085] Compared with Example 4, in Comparative Example 5, only the modified calcium hydroxide prepared in Example 1 added therein was replaced with calcium hydroxide in equal amount, and the other components were exactly the same as those in Example 4.

[0086] Comparative Example 6

[0087] Compared with Example 7, in Comparative Example 6, only the thickener prepared in Example 4 added therein was replaced with the thickener prepared in Comparative Example 3 in equal amount, and the other components and the preparation method were exactly the same as those in Example 4.

[0088] Comparative Example 7

[0089] Compared with Example 7, in Comparative Example 7, only the thickener prepared in Example 4 added therein was replaced with the thickener prepared in Comparative Example 4 in equal amount, and the other components and the preparation method were exactly the same as those in Example 4.

[0090] Comparative Example 8

[0091] Compared with Example 7, in Comparative Example 8, only the thickener prepared in Example 4 added therein was replaced with the thickener prepared in Comparative Example 5 in equal amount, and the other components and the preparation method were exactly the same as those in Example 4.

[0092] Performance Detection

[0093] (1) Dropping Point: Detect the performance according to GB / T 3498, and the detection data are shown in Table 1;

[0094] (2) Penetration: Detect the performance according to GB / T 269, and the detection data are shown in Table 1;

[0095] (3) Four-Ball Wear: Detect the performance according to SH / T 0189, and the detection data are shown in Table 1;

[0096] Table 1: Statistical Table of Performance Detection Data for Examples 7 - 9 and Comparative Examples 6 - 8

[0097]

[0098] As can be seen from Table 1, the grease prepared in this application has a high dropping point, so it has excellent temperature resistance. Under the high-temperature conditions generated by friction during use, it is not easy to lose, and the service life of the grease itself is long. In the four-ball wear test, the grease prepared in this application shows low wear and good anti-wear and extreme pressure performance.

[0099] The above has described in detail one embodiment of the present invention, but the content described is only the preferred embodiment of the present invention and cannot be considered as limiting the scope of implementation of the present invention. Any equivalent changes and improvements made according to the scope of the application of the present invention should still fall within the scope covered by the patent of the present invention.

Claims

1. Automotive constant velocity joint anti-rust lubricating grease, characterized in that, The grease is composed of the following raw materials in parts by weight: 65 - 75 parts of base oil, 0.5 - 5 parts of thickener, 1 - 5 parts of antioxidant, 0.1 - 0.5 parts of rust inhibitor, 0.5 - 5 parts of extreme pressure and anti-wear agent; The preparation method of the thickener includes the following steps: S1: Mix 12 - hydroxy stearic acid and sebacic acid, heat up to 85 - 90 °C, add modified calcium hydroxide, keep the temperature for reaction for 0.25 - 0.5 h, heat up to 90 - 100 °C, add lithium hydroxide, and react for 0.5 - 1.5 h; S2: Continue to heat up to 140 - 150 °C, and keep the temperature for reaction for 0.5 - 1 h under stirring; S3: Continue to heat up to 190 - 210 °C, and keep the temperature for reaction for 0.2 - 0.5 h to obtain the thickener; The preparation method of the modified calcium hydroxide includes the following steps: A1: Mix the calcined limestone and distilled water evenly, add propylene glycol under stirring, age for 3 - 6 h, and dry to obtain Component One; A2: Add Component One, citric acid monohydrate, and deionized water into the reaction kettle, heat up to 40 - 50 °C, keep the temperature for 3 - 6 h, wash with water and dry to obtain Component Two; A3: Add Component Two, N,N'-dicyclohexylcarbodiimide, and absolute ethanol into the reaction kettle, add an aqueous solution of sulfanilic acid, heat up to 50 - 55 °C, keep the temperature for 3 - 6 h, filter, wash, and dry to obtain the modified calcium hydroxide.

2. The automotive constant velocity joint anti-rust grease according to claim 1, wherein In S1, the mass ratio of 1,2 - hydroxy stearic acid, sebacic acid, modified calcium hydroxide, and lithium hydroxide is 5 g:4 g:2 g:2 g.

3. The automotive constant velocity joint anti-rust grease according to claim 1, characterized in that In A1, the mass ratio of the calcined limestone:distilled water:propylene glycol is 10:50 - 100:5 - 10.

4. The automotive constant velocity joint anti-rust grease according to claim 1, characterized in that In A2, the mass ratio of Component One, citric acid monohydrate, and deionized water is 5:1 - 3:50 - 100.

5. The automotive constant velocity joint anti-rust grease according to claim 1, characterized in that, In A3, the addition ratio of Component Two, N,N'-dicyclohexylcarbodiimide, absolute ethanol, and the aqueous solution of sulfanilic acid is 0.3 g - 0.5 g:0.5 g - 1 g:50 mL - 100 mL:75 mL, where 75 mL of the aqueous solution of sulfanilic acid contains 0.3 g - 0.5 g of sulfanilic acid.

6. A preparation method of the automotive constant velocity joint anti-rust grease as described in claim 1, characterized in that, It includes the following steps: Add the base oil and the thickener into the reaction kettle, heat up to 70 - 90 °C, then add the antioxidant, rust inhibitor, and extreme pressure and anti-wear agent, and grind to obtain the grease.

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