Perfluoropolyether lubricating grease for high temperature and low volatility

Abstract

The perfluoropolyether lubricating grease comprises the following raw materials in percentage by weight: 20-35% of polytetrafluoroethylene and 65-80% of perfluoropolyether oil, and a modification treatment agent accounting for 2-5% of the total amount of the lubricating grease is also added into the lubricating grease. A preparation method of the modification treating agent comprises the following steps: blending 2-5 parts of fibrous barium sulfate, 1-3 parts of yttrium nitrate solution and 2-4 parts of sodium citrate, carrying out ball milling treatment, and after the ball milling is finished, carrying out suction filtration and drying to obtain the modified fibrous barium sulfate. The low-volatility perfluoropolyether lubricating grease provided by the invention meets the defect of large volatilization amount of equipment under high-temperature and high-vacuum conditions, and the low-volatility perfluoropolyether lubricating grease is developed and has the characteristics that the low-volatility perfluoropolyether lubricating grease can effectively meet the requirement of low volatility under the high-temperature and high-vacuum conditions; compared with the existing perfluoropolyether lubricating grease on the market, the perfluoropolyether lubricating grease provided by the invention has better volatility, and can meet the requirement of low volatility of equipment at a high temperature of 360 DEG C under a vacuum condition.

Description

Technical Field

[0001] The invention relates to the technical field of lubricating grease, and in particular to a high-temperature and low-volatility perfluoropolyether lubricating grease. Background Art

[0002] Perfluoropolyether grease is a white perfluoropolyether grease made by thickening polytetrafluoroethylene with highly chemically stable perfluoropolyether oil and adding special anti-corrosion additives. This fluorine high-temperature grease is specially used for bearings in high-temperature, high-load, chemically corrosive environments and parts that require lifelong lubrication. It has excellent chemical inertness, durability and low volatility, and is suitable for temperature range: -20 ~ +360 ℃. It is suitable for lubrication of film stretching tenter bearings, heat setting machine conveyor belt bearings, high-temperature paint oven chain bearings, PTA centrifuge differential bearings, automobile wiper motor bearings, and corrugated paper machine bearings; it is suitable for lifelong lubrication of parts and components of precision machines, optical instruments, office equipment, and clean room equipment; it is used for lubrication and sealing of bearings, pumps, valves, and seals of semiconductor equipment, chemical process machinery, and high vacuum environment equipment; it can also be used for pumps and valves that come into contact with corrosive gases and liquids (such as halogens, liquid oxygen, etc.).

[0003] With the development of the times and the advancement of science and technology, more and more products are produced under high temperature and high vacuum conditions. At the same time, the requirements for lubrication protection of the environment and equipment are getting higher and higher. Many perfluoropolyether greases that could be used before have been gradually eliminated as technical requirements have been improved. This requires improving the performance of perfluoropolyether greases in accordance with the requirements of equipment use conditions. The existing greases have poor volatility under high temperature conditions, which limits the efficiency of product use. Based on this, the present invention further improves it. Summary of the invention

[0004] In view of the defects of the prior art, the object of the present invention is to provide a high-temperature and low-volatility perfluoropolyether grease to solve the problems raised in the above background technology.

[0005] The present invention solves the technical problem by adopting the following technical solution:

[0006] The invention provides a high-temperature low-volatile perfluoropolyether lubricating grease, which comprises the following raw materials in weight percentage: 20-35% of polytetrafluoroethylene and 65-80% of perfluoropolyether oil.

[0007] Preferably, the grease further contains 2-5% of a modifying agent based on the total amount of the grease;

[0008] The preparation method of the modified treatment agent is as follows:

[0009] 2-5 parts of fibrous barium sulfate, 1-3 parts of yttrium nitrate solution and 2-4 parts of sodium citrate are mixed and ball-milled, and after the ball-milling is completed, the mixture is filtered and dried to obtain modified fibrous barium sulfate;

[0010] 5-8 parts of nano calcium carbonate are added to 8-12 parts of sodium lignin sulfonate solution, and then 2-4 parts of silane coupling agent and 2-4 parts of modified fibrous barium sulfate are added and mixed thoroughly, and finally washed with water and dried to obtain a modified treatment agent.

[0011] Preferably, the mass fraction of the yttrium nitrate solution is 2-5%; the mass fraction of the sodium lignin sulfonate solution is 3-6%.

[0012] Preferably, the silane coupling agent is silane coupling agent KH550.

[0013] Preferably, the ball milling speed of the blending ball milling treatment is 1000-1500 r / min, and the ball milling is 1 hour;

[0014] Preferably, the rotation speed for sufficient blending is 550-750 r / min, and the sufficient blending time is 20-30 min.

[0015] The present invention provides a method for preparing a high-temperature, low-volatility perfluoropolyether grease, comprising the following steps:

[0016] The polytetrafluoroethylene (PTFE), perfluoropolyether oil (PFPE) and the modifying agent are mixed and stirred evenly, and baked at high temperature for 2 hours so that the polytetrafluoroethylene (PTFE) and the modifying agent can better dilute and wrap the perfluoropolyether oil (PFPE). After baking, the three-roll mill is used for 3-4 times to obtain the product.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention meets the deficiency of large volatility of equipment under high temperature and high vacuum conditions, and develops a low-volatility perfluoropolyether grease. The low-volatility perfluoropolyether grease is characterized in that it can effectively meet the requirements of low volatility under high temperature and high vacuum conditions. Compared with the existing perfluoropolyether grease on the market, it has better volatility and can meet the low volatility requirements of equipment under high temperature 200°C 360°C and vacuum conditions. DETAILED DESCRIPTION

[0019] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The high-temperature and low-volatility perfluoropolyether grease of this embodiment comprises the following raw materials in weight percentage: 20-35% polytetrafluoroethylene and 65-80% perfluoropolyether oil.

[0021] The grease of this embodiment also contains a modifying agent in an amount of 2-5% of the total amount of the grease;

[0022] The preparation method of the modified treatment agent is as follows:

[0023] 2-5 parts of fibrous barium sulfate, 1-3 parts of yttrium nitrate solution and 2-4 parts of sodium citrate are mixed and ball-milled, and after the ball-milling is completed, the mixture is filtered and dried to obtain modified fibrous barium sulfate;

[0024] 5-8 parts of nano calcium carbonate are added to 8-12 parts of sodium lignin sulfonate solution, and then 2-4 parts of silane coupling agent and 2-4 parts of modified fibrous barium sulfate are added and mixed thoroughly, and finally washed with water and dried to obtain a modified treatment agent.

[0025] The mass fraction of the yttrium nitrate solution in this embodiment is 2-5%; the mass fraction of the sodium lignin sulfonate solution is 3-6%.

[0026] The silane coupling agent of this embodiment is silane coupling agent KH550.

[0027] The ball milling speed of the blended ball milling treatment in this embodiment is 1000-1500r / min, and the ball milling is 1h;

[0028] The rotation speed for sufficient blending in this embodiment is 550-750 r / min, and the sufficient blending time is 20-30 min.

[0029] The present invention provides a method for preparing a high-temperature, low-volatility perfluoropolyether grease, comprising the following steps:

[0030] The polytetrafluoroethylene (PTFE), perfluoropolyether oil (PFPE) and the modifying agent are mixed and stirred evenly, and baked at high temperature for 2 hours so that the polytetrafluoroethylene (PTFE) and the modifying agent can better dilute and wrap the perfluoropolyether oil (PFPE). After baking, the three-roll mill is used for 3-4 times to obtain the product.

[0031] Example 1:

[0032] 20% polytetrafluoroethylene (PTFE) and 80% perfluoropolyether oil (PFPE) were mixed and stirred evenly, and after high-temperature baking for 2 hours, three-roll milling was performed for 3-4 times, and the test data was recorded.

[0033] The grease also contains 2-5% of the total amount of the grease as a modifier.

[0034] The preparation method of the modified treatment agent is as follows:

[0035] Blending 2 parts of fibrous barium sulfate, 1 part of yttrium nitrate solution and 2 parts of sodium citrate, and subjecting the mixture to ball milling, filtering and drying after the ball milling is completed, to obtain modified fibrous barium sulfate;

[0036] 5 parts of nano calcium carbonate are added into 8 parts of sodium lignin sulfonate solution, and then 2 parts of silane coupling agent and 2 parts of modified fibrous barium sulfate are added and mixed thoroughly, and finally washed with water and dried to obtain a modified treatment agent.

[0037] The mass fraction of the yttrium nitrate solution in this embodiment is 2%; the mass fraction of the sodium lignin sulfonate solution is 3%.

[0038] The silane coupling agent of this embodiment is silane coupling agent KH550.

[0039] The ball milling speed of the blended ball milling treatment in this embodiment is 1000r / min, and the ball milling is 1h;

[0040] The rotation speed for sufficient blending in this embodiment is 550 r / min, and the sufficient blending time is 20 min.

[0041] As shown in Table 1

[0042] project index Appearance White paste PB(GB / T3142)N 186 PD(GB / T3142)N 4900 Cone penetration (GB / T269) mm 268 Steel mesh oil separation (SH / T0324) % 1.2 Evaporation capacity (GB / T7325, 300℃, 22H) 0.08

[0043] Table 1

[0044] Test results: The data test can meet the requirements by using specially treated perfluoropolyether oil (PFPE) thickened with polytetrafluoroethylene (PTFE).

[0045] Experiments show that specially treated 80% perfluoropolyether oil (PFPE) thickened with 20% polytetrafluoroethylene (PTFE) can fully achieve low volatility under high temperature and high pressure conditions.

[0046] Example 2:

[0047] 25% polytetrafluoroethylene (PTFE) and 75% perfluoropolyether oil (PFPE) were mixed and stirred evenly, and after high-temperature baking for 2 hours, three-roll milling was performed for 4 times, and the test data were recorded.

[0048] The grease also contains 2-5% of the total amount of the grease as a modifier.

[0049] The preparation method of the modified treatment agent is as follows:

[0050] 5 parts of fibrous barium sulfate, 3 parts of yttrium nitrate solution and 4 parts of sodium citrate are mixed and ball-milled, and after the ball-milling is completed, the mixture is filtered and dried to obtain modified fibrous barium sulfate;

[0051] 8 parts of nano calcium carbonate are added into 12 parts of sodium lignin sulfonate solution, and then 4 parts of silane coupling agent and 4 parts of modified fibrous barium sulfate are added and mixed thoroughly, and finally washed with water and dried to obtain a modified treatment agent.

[0052] The mass fraction of the yttrium nitrate solution in this embodiment is 5%; the mass fraction of the sodium lignin sulfonate solution is 6%.

[0053] The silane coupling agent of this embodiment is silane coupling agent KH550.

[0054] The ball milling speed of the blended ball milling treatment in this embodiment is 1500r / min, and the ball milling is 1h;

[0055] The rotation speed for sufficient blending in this embodiment is 750r / min, and the sufficient blending time is 20-30min.

[0056] As shown in Table 2

[0057]

[0058] Table 2

[0059] Test results: The data test can meet the requirements by using specially treated perfluoropolyether oil (PFPE) thickened with polytetrafluoroethylene (PTFE).

[0060] Experiments show that specially treated 75% perfluoropolyether oil (PFPE) thickened with 25% polytetrafluoroethylene (PTFE) can fully achieve low volatility under high temperature and high pressure conditions.

[0061] Example 3:

[0062] 30% polytetrafluoroethylene (PTFE) and 70% perfluoropolyether oil (PFPE) were mixed and stirred evenly, and after high-temperature baking for 2 hours, three-roll milling was performed for 3-4 times, and the test data were recorded.

[0063] The grease also contains 2-5% of the total amount of the grease as a modifier.

[0064] The preparation method of the modified treatment agent is as follows:

[0065] 3.5 parts of fibrous barium sulfate, 2 parts of yttrium nitrate solution and 3 parts of sodium citrate are mixed and ball-milled, and after the ball-milling is completed, the mixture is filtered and dried to obtain modified fibrous barium sulfate;

[0066] 6.5 parts of nano calcium carbonate were added to 10 parts of sodium lignin sulfonate solution, and then 3 parts of silane coupling agent and 3 parts of modified fibrous barium sulfate were added and mixed thoroughly, and finally washed with water and dried to obtain a modified treatment agent.

[0067] The mass fraction of the yttrium nitrate solution in this embodiment is 3.5%; the mass fraction of the sodium lignin sulfonate solution is 4.5%.

[0068] The silane coupling agent of this embodiment is silane coupling agent KH550.

[0069] The ball milling speed of the blended ball milling treatment in this embodiment is 1250r / min, and the ball milling is 1h;

[0070] The rotation speed for sufficient blending in this embodiment is 600 r / min, and the sufficient blending time is 25 min.

[0071] As shown in Table 3

[0072]

[0073]

[0074] Table 3

[0075] Test results: The data test can meet the requirements by using specially treated perfluoropolyether oil (PFPE) thickened with polytetrafluoroethylene (PTFE).

[0076] Experiments show that specially treated 70% perfluoropolyether oil (PFPE) thickened with 30% polytetrafluoroethylene (PTFE) can fully achieve low volatility under high temperature and high pressure conditions.

[0077] Example 4:

[0078] 35% polytetrafluoroethylene (PTFE) and 65% perfluoropolyether oil (PFPE) were mixed and stirred evenly, and after high-temperature baking for 2 hours, three-roll milling was performed for 3-4 times, and the test data were recorded.

[0079] The grease also contains 4% of the total amount of the grease as a modifier;

[0080] The preparation method of the modified treatment agent is as follows:

[0081] 3 parts of fibrous barium sulfate, 2 parts of yttrium nitrate solution and 3 parts of sodium citrate are mixed and ball-milled, and after the ball-milling is completed, the mixture is filtered and dried to obtain modified fibrous barium sulfate;

[0082] 6 parts of nano calcium carbonate are added into 9 parts of sodium lignin sulfonate solution, and then 3 parts of silane coupling agent and 3 parts of modified fibrous barium sulfate are added and mixed thoroughly, and finally washed with water and dried to obtain a modified treatment agent.

[0083] The mass fraction of the yttrium nitrate solution in this embodiment is 4%; the mass fraction of the sodium lignin sulfonate solution is 5%.

[0084] The silane coupling agent of this embodiment is silane coupling agent KH550.

[0085] The ball milling speed of the blended ball milling treatment in this embodiment is 1200r / min, and the ball milling is 1h;

[0086] The rotation speed for sufficient blending in this embodiment is 600 r / min, and the sufficient blending time is 22 min.

[0087] As shown in Table 4

[0088]

[0089]

[0090] Table 4

[0091] Test results: The data test can meet the requirements by using specially treated perfluoropolyether oil (PFPE) thickened with polytetrafluoroethylene (PTFE).

[0092] Experiments show that specially treated 65% perfluoropolyether oil (PFPE) thickened with 35% polytetrafluoroethylene (PTFE) can fully achieve low volatility under high temperature and high pressure conditions.

[0093] In order to meet the problem of high volatility of equipment under high temperature and high vacuum conditions, low volatility perfluoropolyether grease has been developed. The characteristic of low volatility perfluoropolyether grease is that it can effectively meet the requirements of low volatility under high temperature and high vacuum conditions. Compared with the existing perfluoropolyether grease on the market, it has better volatility and can meet the low volatility requirements of equipment under high temperature of 360°C and vacuum conditions.

[0094] Through the above experiments, there is not much fluctuation in the data detection of different proportions of perfluoropolyether oil (PFPE) and polytetrafluoroethylene (PTFE) thickened into grease. The volatility (evaporation) test is relatively stable, and there is no large data fluctuation due to different proportions. The experiment shows that the specially treated perfluoropolyether oil can fully achieve low volatility under high temperature and high pressure conditions.

[0095] 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 present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0096] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A high temperature and low volatility perfluoropolyether grease, characterized in that: The invention comprises the following raw materials in weight percentage: polytetrafluoroethylene accounts for 20-35% and perfluoropolyether oil accounts for 65-80%.

2. The high temperature and low volatility perfluoropolyether grease according to claim 1, characterized in that: The grease is further added with a modifying agent in an amount of 2-5% of the total amount of the grease; The preparation method of the modified treatment agent is as follows: 2-5 parts of fibrous barium sulfate, 1-3 parts of yttrium nitrate solution and 2-4 parts of sodium citrate are mixed and ball-milled, and after the ball-milling is completed, the mixture is filtered and dried to obtain modified fibrous barium sulfate; 5-8 parts of nano calcium carbonate are added to 8-12 parts of sodium lignin sulfonate solution, and then 2-4 parts of silane coupling agent and 2-4 parts of modified fibrous barium sulfate are added and mixed thoroughly, and finally washed with water and dried to obtain a modified treatment agent.

3. The high temperature and low volatility perfluoropolyether grease according to claim 2, characterized in that: The mass fraction of the yttrium nitrate solution is 2-5%; the mass fraction of the sodium lignin sulfonate solution is 3-6%.

4. The high temperature and low volatility perfluoropolyether grease according to claim 2, characterized in that: The silane coupling agent is silane coupling agent KH550.

5. The high temperature and low volatility perfluoropolyether grease according to claim 2, characterized in that: The ball milling speed of the blended ball milling treatment is 1000-1500 r / min, and the ball milling is for 1 hour.

6. The high temperature and low volatility perfluoropolyether grease according to claim 2, characterized in that: The rotation speed for sufficient blending is 550-750r / min, and the sufficient blending time is 20-30min.

7. A method for preparing a high-temperature, low-volatility perfluoropolyether grease, characterized in that: The following steps are involved: The polytetrafluoroethylene (PTFE), perfluoropolyether oil (PFPE) and the modifying agent are mixed and stirred evenly, and baked at high temperature for 2 hours so that the polytetrafluoroethylene (PTFE) and the modifying agent can better dilute and wrap the perfluoropolyether oil (PFPE). After baking, the three-roll mill is used for 3-4 times to obtain the product.

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