Ultrahigh vacuum lubricating grease and preparation method thereof
By using perfluoropolyether oil, polytetrafluoroethylene, extreme pressure antiwear agent and rust preventing agent in the grease, and preparing by film distillation and high-speed stirring under high vacuum conditions, the problem of poor volatility performance of existing greases under high and low temperatures and heavy load conditions is solved, and stable lubricating performance in high temperature and high vacuum environment is achieved.
Patent Information
- Application Number
- CN202411636613.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-15
- Publication Date
- 2025-02-25
AI Technical Summary
The existing grease has poor volatile properties under high and low temperature and heavy load conditions, and insufficient high temperature vacuum, which limits the efficiency of the product.
An ultra-high vacuum grease, including perfluoropolyether oil, polytetrafluoroethylene, extreme pressure antiwear agent and anti-rust agent, is prepared by film distillation and high-speed stirring under high vacuum conditions to ensure the stable performance of the grease in a high temperature and high vacuum environment.
It has achieved excellent low volatility under ultra-high vacuum conditions, and can exert stable lubrication protection performance under maximum temperature of 280℃ and ultra-high vacuum conditions of 3.5×10-9mbar, which significantly improves the efficiency of the product.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of lubricating grease, and in particular to an ultra-high vacuum lubricating grease and a preparation method thereof. Background Art
[0002] With the development and improvement of science and technology and the continuous progress and upgrading of mechanical equipment, modern mechanical technology has begun to develop in the direction of high temperature, high speed, small size, environmental protection, long life and intelligence, especially in the optoelectronic semiconductor industry, chip manufacturing industry, and aerospace field. Because the application environment has very demanding working conditions such as ultra-high vacuum, high and low temperature, cleanliness, radiation resistance, and long life, this type of grease has been monopolized by European and American companies. Ultra-high vacuum perfluoropolyether grease is a white perfluoropolyether grease made by thickening polytetrafluoroethylene with highly chemically stable perfluoropolyether oil and adding special anti-corrosion, extreme pressure and anti-wear additives. This fluorine grease is specially used for precision bearings, linear guides, screws and parts requiring lifelong lubrication in high vacuum, high temperature, high load and chemical corrosion environments. It has excellent chemical inertness, durability, excellent high and low temperature performance and oxidation stability, vacuum resistance and low volatility. The applicable temperature range is -65~+280℃. It is specially used for clean room equipment in the optoelectronic chip semiconductor industry and robots, bearings, guides, etc. of semiconductor manufacturing equipment. It is also suitable for harsh occasions such as high temperature, corrosion, solvents, optical equipment, precision instruments, electronic products, aerospace, military, nuclear energy and nuclear power, high vacuum, etc., where the volatilization of lubricating materials needs to be avoided. It has lifelong lubrication; 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] The existing grease has poor volatility under high and low temperature and heavy load conditions, and the product has poor high temperature vacuum performance, which limits the use efficiency of the product. 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 an ultra-high vacuum grease and a preparation method thereof 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 present invention provides an ultra-high vacuum grease, comprising the following raw materials in parts by weight:
[0007] 5-80 parts of perfluoropolyether oil, 15-30 parts of polytetrafluoroethylene, 1-5 parts of extreme pressure anti-wear agent, and 0.2-2 parts of rust inhibitor.
[0008] Preferably, the extreme pressure anti-wear agent is one of diethyl phosphite or dibutyl phosphite.
[0009] Preferably, the extreme pressure anti-wear agent is further added with a nano-alumina agent in an amount of 2-5% of the total amount of the extreme pressure anti-wear agent;
[0010] The preparation method of nano alumina agent is as follows:
[0011] Prepare 2-5% by mass of yttrium nitrate solution, 3-4% by mass of chitosan solution and 2-5% by mass of sodium dodecylbenzene sulfonate solution;
[0012] 5-8 parts of nano-alumina, 1-3 parts of nano-silica sol, and 2-5 parts of yttrium nitrate solution are mixed and added into 6-10 parts of chitosan solution, and then 1-2 parts of sodium dodecylbenzene sulfonate solution are added and mixed and ball-milled. After the ball-milling is completed, the mixture is washed with water, filtered, and dried to obtain a nano-alumina agent.
[0013] Preferably, the ball milling speed of the blended ball milling treatment is 1000-1500 r / min, and the ball milling is for 2 hours.
[0014] Preferably, the rust inhibitor is barium dinonylnaphthalenesulfonate.
[0015] A method for preparing ultra-high vacuum grease comprises the following steps:
[0016] Step 1: First, the PFPE base oil has a kinematic viscosity of 150 to 220 mm2 / s at 40°C, and is subjected to thin film distillation of fluidity under high vacuum conditions in a polymer purifier, and the PFPE base oil is subjected to four dynamic, high temperature, and high vacuum pretreatments;
[0017] Step 2:
[0018] The polytetrafluoroethylene (PTFE) and the obtained effective heavy component perfluoropolyether oil (PFPE) are mixed and stirred at high speed, and then the extreme pressure anti-wear agent and the rust inhibitor are added and stirred for 1-2 hours at 150 degrees in a vacuum reactor, so that the polytetrafluoroethylene (PTFE) can better dilute and wrap the perfluoropolyether oil (PFPE);
[0019] Step 3:
[0020] After the vacuum stirring is completed, the product is ground 3-4 times with a three-roller mill in a clean room to obtain the product, which is then vacuum packaged and stored.
[0021] Preferably, the thin film distillation is carried out under high vacuum of 3.5×10-9 mbar and high temperature of 250° C. to 290° C.
[0022] Compared with the prior art, the present invention has the following beneficial effects:
[0023] The invention satisfies the requirement that the equipment has excellent low volatility performance under ultra-high vacuum conditions, which is superior to the existing vacuum-resistant perfluoropolyether grease on the market, and can achieve the equipment at a maximum temperature of 280°C and an ultra-high vacuum of 3.5×10 -9 It exerts stable lubrication and protection performance under mbar conditions; there is not much fluctuation in data detection for different proportions of effective heavy components of perfluoropolyether oil (PFPE) and polytetrafluoroethylene (PTFE) thickened into grease, and it is relatively stable in the test of high vacuum volatility (evaporation amount), and there is no large data fluctuation due to different proportions. The experiment shows that the specially treated perfluoropolyether oil can fully achieve high temperature and high vacuum performance. DETAILED DESCRIPTION
[0024] 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.
[0025] An ultra-high vacuum grease of this embodiment includes the following raw materials in parts by weight:
[0026] 5-80 parts of perfluoropolyether oil, 15-30 parts of polytetrafluoroethylene, 1-5 parts of extreme pressure anti-wear agent, and 0.2-2 parts of rust inhibitor.
[0027] The extreme pressure anti-wear agent of this embodiment is one of diethyl phosphite or dibutyl phosphite.
[0028] The extreme pressure anti-wear agent of this embodiment also contains 2-5% of the total amount of the extreme pressure anti-wear agent as a nano-alumina agent;
[0029] The preparation method of nano alumina agent is as follows:
[0030] Prepare 2-5% by mass of yttrium nitrate solution, 3-4% by mass of chitosan solution and 2-5% by mass of sodium dodecylbenzene sulfonate solution;
[0031] 5-8 parts of nano-alumina, 1-3 parts of nano-silica sol, and 2-5 parts of yttrium nitrate solution are mixed and added into 6-10 parts of chitosan solution, and then 1-2 parts of sodium dodecylbenzene sulfonate solution are added and mixed and ball-milled. After the ball-milling is completed, the mixture is washed with water, filtered, and dried to obtain a nano-alumina agent.
[0032] The ball milling speed of the blended ball milling treatment in this embodiment is 1000-1500 r / min, and the ball milling is 2 h.
[0033] The rust inhibitor of this embodiment is barium dinonylnaphthalenesulfonate.
[0034] A method for preparing ultra-high vacuum grease comprises the following steps:
[0035] Step 1: First, the PFPE base oil has a kinematic viscosity of 150 to 220 mm2 / s at 40°C, and is subjected to thin film distillation of fluidity under high vacuum conditions in a polymer purifier, and the PFPE base oil is subjected to four dynamic, high temperature, and high vacuum pretreatments;
[0036] Step 2:
[0037] The polytetrafluoroethylene (PTFE) and the obtained effective heavy component perfluoropolyether oil (PFPE) are mixed and stirred at high speed, and then the extreme pressure anti-wear agent and the rust inhibitor are added and stirred for 1-2 hours at 150 degrees in a vacuum reactor, so that the polytetrafluoroethylene (PTFE) can better dilute and wrap the perfluoropolyether oil (PFPE);
[0038] Step 3:
[0039] After the vacuum stirring is completed, the product is ground 3-4 times with a three-roller mill in a clean room to obtain the product, which is then vacuum packaged and stored.
[0040] The high vacuum of the thin film distillation in this example is 3.5×10 -9 mbar high temperature 250℃~290℃ condition.
[0041] Example 1:
[0042] 18% polytetrafluoroethylene (PTFE) and 77% perfluoropolyether oil (PFPE) effective heavy components, 4% extreme pressure anti-wear agent and 1% rust inhibitor were mixed and stirred evenly in a high-temperature vacuum kettle, and then three-roll milled for 3-4 times, and the test data were recorded.
[0043] The extreme pressure anti-wear agent also contains 3.5% of the total amount of the extreme pressure anti-wear agent as nano-alumina agent;
[0044] The preparation method of nano alumina agent is as follows:
[0045] Prepare 3.5% by mass of yttrium nitrate solution, 3.5% by mass of chitosan solution and 3.5% by mass of sodium dodecylbenzene sulfonate solution;
[0046] 6.5 parts of nano-alumina, 2 parts of nano-silica sol, and 3.5 parts of yttrium nitrate solution were mixed and added into 8 parts of chitosan solution, and then 1.5 parts of sodium dodecylbenzene sulfonate solution were added and mixed and ball-milled. After the ball-milling was completed, the mixture was washed with water, filtered, and dried to obtain a nano-alumina agent.
[0047] The ball milling speed of the blended ball milling treatment in this embodiment is 1250 r / min, and the ball milling is performed for 2 hours.
[0048] As shown in Table 1
[0049] Test items Test Standards Control indicators Appearance — White uniform ointment Maximum load PB of four balls without biting SH / T 0202 186N Four-ball extreme pressure sintering load PD SH / T 0202 6076N Unworked cone penetration (25℃) GB / T 269 283mm Steel mesh oil separation (100℃, 24h) SH / T 0324 3.8％ Vacuum evaporation capacity (250℃) GB / T 7325 0.07％ Steel corrosion (100℃, 24h) GB / T 7326 qualified
[0050] Table 1
[0051] Test results: The effective heavy components of pretreated perfluoropolyether oil (PFPE) are thickened with polytetrafluoroethylene (PTFE) and special additives are added, and the physical and chemical performance test data meet the requirements.
[0052] Experiments show that the effective heavy components of pretreated 77% perfluoropolyether oil (PFPE) can achieve high vacuum performance under high temperature conditions by thickening with 18% polytetrafluoroethylene (PTFE) and adding 4% extreme pressure anti-wear agent and 1% rust inhibitor.
[0053] Example 2:
[0054] 21% polytetrafluoroethylene (PTFE) and 75% perfluoropolyether oil (PFPE) effective heavy component, 3.5% extreme pressure anti-wear agent and 0.5% rust inhibitor were mixed and stirred in a high-temperature vacuum kettle, and then three-roll milled for 3-4 times, and the test data were recorded.
[0055] Test items Test Standards Control indicators Appearance — White uniform ointment Maximum load PB of four balls without biting SH / T 0202 186N Four-ball extreme pressure sintering load PD SH / T 0202 6076N Unworked cone penetration (25℃) GB / T 269 280mm Steel mesh oil separation (100℃, 24h) SH / T 0324 3.1％ Vacuum evaporation capacity (250℃) GB / T 7325 0.05％ Steel corrosion (100℃, 24h) GB / T 7326 qualified
[0056] Table 2
[0057] Test results: The effective heavy components of the pretreated perfluoropolyether oil (PFPE) were thickened with polytetrafluoroethylene (PTFE) and special additives were added, and the physical and chemical performance test data met the requirements.
[0058] Experiments show that the effective heavy components of pretreated 75% perfluoropolyether oil (PFPE) can achieve high vacuum performance under high temperature conditions by thickening with 21% polytetrafluoroethylene (PTFE) and adding 3.5% extreme pressure anti-wear agent and 0.5% rust inhibitor.
[0059] Example 3:
[0060] 27% polytetrafluoroethylene (PTFE) and 69% perfluoropolyether oil (PFPE) effective heavy components, 3.5% extreme pressure anti-wear agent and 1.5% rust inhibitor were mixed and stirred in a high-temperature vacuum kettle, and then three-roll milled for 3-4 times, and the test data were recorded.
[0061]
[0062]
[0063] Table 3
[0064] Test results: The effective heavy components of pretreated perfluoropolyether oil (PFPE) are thickened with polytetrafluoroethylene (PTFE) and special additives are added, and the physical and chemical performance test data meet the requirements.
[0065] Experiments show that the effective heavy components of pretreated 69% perfluoropolyether oil (PFPE) can achieve high vacuum performance under high temperature conditions by thickening with 27% polytetrafluoroethylene (PTFE) and adding 3.5% extreme pressure anti-wear agent and 1.5% rust inhibitor.
[0066] Example 4:
[0067] 30% polytetrafluoroethylene (PTFE) and 67% perfluoropolyether oil (PFPE) effective heavy components, 2.2% extreme pressure anti-wear agent and 0.8% rust inhibitor were mixed and stirred in a high-temperature vacuum kettle and then ground with a three-roller mill for 3-4 times, and the test data were recorded.
[0068] Test items Test Standards Control indicators Appearance — White uniform ointment Maximum load PB of four balls without biting SH / T 0202 186N Four-ball extreme pressure sintering load PD SH / T 0202 4900N Unworked cone penetration (25℃) GB / T 269 272mm Steel mesh oil separation (100℃, 24h) SH / T 0324 2.4％ Vacuum evaporation capacity (250℃) GB / T 7325 0.04％ Steel corrosion (100℃, 24h) GB / T 7326 qualified
[0069] Table 4
[0070] Test results: The effective heavy components of pretreated perfluoropolyether oil (PFPE) are thickened with polytetrafluoroethylene (PTFE) and special additives are added, and the physical and chemical performance test data meet the requirements.
[0071] Experiments show that the effective heavy components of pretreated 67% perfluoropolyether oil (PFPE) can achieve high vacuum performance under high temperature conditions by thickening with 30% polytetrafluoroethylene (PTFE) and adding 2.2% extreme pressure anti-wear agent and 0.8% rust inhibitor.
[0072] The above four groups of experiments prove that there is not much fluctuation in the data detection for different proportions of effective heavy components of perfluoropolyether oil (PFPE) and polytetrafluoroethylene (PTFE) thickened into grease. The test of high vacuum volatility (evaporation amount) is relatively stable, and there is no large data fluctuation due to different proportions. The experiments show that specially treated perfluoropolyether oil can fully achieve high temperature and high vacuum performance.
[0073] It meets the requirements of equipment with excellent low volatility under ultra-high vacuum conditions. It is superior to the existing vacuum-resistant perfluoropolyether grease on the market. It can achieve equipment with a maximum temperature of 280°C and an ultra-high vacuum of 3.5×10 -9 It can exert stable lubrication protection performance under mbar conditions.
[0074] 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.
[0075] 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. An ultra-high vacuum grease, characterized in that: It includes the following raw materials in parts by weight: 5-80 parts of perfluoropolyether oil, 15-30 parts of polytetrafluoroethylene, 1-5 parts of extreme pressure anti-wear agent, and 0.2-2 parts of rust inhibitor.
2. An ultra-high vacuum grease according to claim 1, characterized in that: The extreme pressure anti-wear agent is one of diethyl phosphite and dibutyl phosphite.
3. An ultra-high vacuum grease according to claim 2, characterized in that: The extreme pressure anti-wear agent is further added with a nano alumina agent accounting for 2-5% of the total amount of the extreme pressure anti-wear agent; The preparation method of nano alumina agent is as follows: Prepare 2-5% by mass of yttrium nitrate solution, 3-4% by mass of chitosan solution and 2-5% by mass of sodium dodecylbenzene sulfonate solution; 5-8 parts of nano-alumina, 1-3 parts of nano-silica sol, and 2-5 parts of yttrium nitrate solution are mixed and added into 6-10 parts of chitosan solution, and then 1-2 parts of sodium dodecylbenzene sulfonate solution are added and mixed and ball-milled. After the ball-milling is completed, the mixture is washed with water, filtered, and dried to obtain a nano-alumina agent.
4. The ultra-high vacuum grease according to claim 3, characterized in that: The ball milling speed of the blended ball milling treatment is 1000-1500 r / min, and the ball milling is performed for 2 hours.
5. The ultra-high vacuum grease according to claim 1, characterized in that: The rust inhibitor is barium dinonylnaphthalenesulfonate.
6. A method for preparing ultra-high vacuum grease, characterized in that: The following steps are involved: Step 1: First, the PFPE base oil has a kinematic viscosity of 150 to 220 mm2 / s at 40°C, and is subjected to thin film distillation of fluidity under high vacuum conditions in a polymer purifier, and the PFPE base oil is subjected to four dynamic, high temperature, and high vacuum pretreatments; Step 2: The polytetrafluoroethylene (PTFE) and the obtained effective heavy component perfluoropolyether oil (PFPE) are mixed and stirred at high speed, and then the extreme pressure anti-wear agent and the rust inhibitor are added and stirred for 1-2 hours at 150 degrees in a vacuum reactor, so that the polytetrafluoroethylene (PTFE) can better dilute and wrap the perfluoropolyether oil (PFPE); Step 3: After the vacuum stirring is completed, the product is ground 3-4 times with a three-roller mill in a clean room to obtain the product, which is then vacuum packaged and stored.
7. The method for preparing an ultra-high vacuum grease according to claim 6, characterized in that: The high vacuum of the thin film distillation is 3.5×10 -9 mbar high temperature 250℃~290℃ condition.