阅读说明：本技术 一种全氟聚醚型的润滑脂及其制备方法 (Perfluoropolyether lubricating grease and preparation method thereof ) 是由 乔姣飞 李伟东 辛虎 于 2019-09-24 设计创作，主要内容包括：本发明公开了一种全氟聚醚型的润滑脂,所述的润滑脂中各组分的重量百分含量为：全氟基础油：52％～80％,优选62％～75％；稠化剂：16％～45％,优选22％～35％；添加剂：1％～5％,优选2％～4％；其中,所述的全氟基础油的分子量为3000～30000g/mol,优选8000～20000g/mol。本发明还提供了上述润滑脂的制备方法,包括1)将全氟基础油、稠化剂和添加剂在搅拌下进行乳化,得到油膏；2)将所述的油膏进行抽真空处理得到所述的全氟聚醚型的润滑脂。本发明提供的润滑脂具有高的热稳定性、氧化安定性,本发明的制备方法反应路线短、所用原料易得、收率高且适合规模化生产。(The invention discloses perfluoropolyether lubricating grease which comprises the following components in percentage by weight: perfluoro base oil: 52 to 80 percent, preferably 62 to 75 percent; a thickening agent: 16% to 45%, preferably 22% to 35%; additive: 1% -5%, preferably 2% -4%; wherein the molecular weight of the perfluorinated base oil is 3000-30000 g/mol, preferably 8000-20000 g/mol. The invention also provides a preparation method of the lubricating grease, which comprises the following steps of 1) emulsifying the perfluorinated base oil, the thickening agent and the additive under stirring to obtain an ointment; 2) and vacuumizing the ointment to obtain the perfluoropolyether lubricating grease. The lubricating grease provided by the invention has high thermal stability and oxidation stability, and the preparation method provided by the invention has the advantages of short reaction route, easily available raw materials, high yield and suitability for large-scale production.)

1. The perfluoropolyether lubricating grease is characterized in that the lubricating grease comprises the following components in percentage by weight:

perfluoro base oil: 52 to 80%, preferably: 62 to 75 percent;

a thickening agent: 16% to 45%, preferably: 22 to 35 percent;

additive: 1% to 5%, preferably: 2% -4%;

wherein the molecular weight of the perfluorinated base oil is 3000-30000 g/mol, preferably 8000-20000 g/mol;

the perfluorinated base oil comprises a compound with a structure shown in the following formula I:

C₃F₇O(CF₂CF₂CF₂O)_mC₂F₅formula I

In formula I, m is an integer.

2. The grease of claim 1, wherein the perfluorinated base oil further comprises a compound of formula ii:

R_f1O(CF₂CF₂O)_m(CF₂O)_nR_f2formula II

In the formula II, m and n are integers, m is more than or equal to 1, preferably m is 1-100, n is more than or equal to 1, preferably n is 1-50; r_f1And R_f2Independently selected from-CF₃、-C₂F₅or-C₃F₇。

3. The grease of claim 1 or 2, wherein the thickener is selected from one or more of polytetrafluoroethylene, chlorotrifluoroethylene-polyethylene copolymer, or tetrafluoroethylene-hexafluoropropylene copolymer; preferably polytetrafluoroethylene.

4. The grease of claim 3, wherein the particle size of the thickener is 0.1-200 μm, preferably 0.1-50 μm.

5. A grease according to any one of claims 1 to 4, wherein the additive is selected from one or more of graphite, silica, molybdenum disulphide or bentonite; preferably silica.

6. A method for producing the perfluoropolyether grease of any one of claims 1 to 5, comprising the steps of:

1) emulsifying perfluoro base oil, a thickening agent and an additive under stirring to obtain an ointment;

2) vacuumizing the ointment to obtain the perfluoropolyether lubricating grease; preferably, the vacuuming treatment is carried out until no bubbles are generated on the surface of the ointment, and the vacuuming treatment is stopped.

7. The preparation method according to claim 6, wherein in the step 1), the stirring speed is 100-3000 rpm, and the stirring time is 1-4 h.

8. The method according to claim 7, wherein the evacuation treatment in step 2) is performed under a vacuum of 100 to 10000Pa and at a temperature of 60 to 90 ℃.

9. The method according to any one of claims 6 to 8, wherein the ointment after the vacuuming treatment is subjected to heat preservation in step 2), preferably for 2 to 8 hours.

10. The method according to claim 9, wherein the ointment after the vacuuming is ground in the step 2) to be sufficiently mixed.

Technical Field

The invention belongs to the technical field of lubricating materials, and particularly relates to perfluoropolyether lubricating grease and a preparation method thereof.

Background

With the development of modern industry, more and more mechanical parts are required to be in contact with various acid, alkali, salt, corrosive gas and strong oxidant media, which puts higher requirements on the chemical corrosion resistance of the lubricating grease.

The traditional chemical-medium-resistant lubricating grease is prepared by mixing and stirring base oil, an antioxidant, an extreme pressure antiwear agent, an oiliness agent, a stabilizer, a tackifier and an antirust agent, and then carrying out retreatment. For example, a patent "CN 201610546160.5 long-life high-temperature bearing grease and a preparation method thereof" discloses a chemical corrosion resistant grease, the used components are octadecylamine, cyclohexylamine, MDI, calcium petroleum sulfonate, petroleum ether, mineral oil, an antioxidant, an extreme pressure antiwear agent, an oiliness agent, a stabilizer, a tackifier and an antirust agent, the preparation process is complex, the required raw materials are more, the yield is low, the grease prepared by the method has general high and low temperature resistance, and the applicable working condition is relatively limited; the perfluoropolyether base oil has good high and low temperature resistance, and the chemical-resistant medium lubricating grease containing the perfluoropolyether base oil as the effective component is not reported in the publication.

In view of the above, it is an urgent need to develop a grease that can resist chemical agents in order to solve the problems of the prior art grease resistant to chemical corrosion.

Disclosure of Invention

In view of the above, the present invention provides a perfluoropolyether type grease which can be applied to lubrication of most parts requiring direct contact with strong acid, strong base, aqueous hydrogen peroxide solution, etc., and which can achieve good performance.

In order to realize the purpose of the invention, the invention adopts the following technical scheme:

the invention provides perfluoropolyether lubricating grease in a first aspect, wherein the components are as follows by weight percent:

perfluoro base oil: 52 to 80%, preferably: 62 to 75 percent;

a thickening agent: 16% to 45%, preferably: 22 to 35 percent;

additive: 1% to 5%, preferably: 2% -4%;

wherein the molecular weight of the perfluorinated base oil is 3000-30000 g/mol, preferably 8000-20000 g/mol;

the perfluorinated base oil comprises a compound with a structure shown in the following formula I:

C₃F₇O(CF₂CF₂CF₂O)_mC₂F₅formula I

In formula I, m is an integer.

In the perfluoropolyether type lubricating grease provided by the invention, the perfluoro base oil also comprises a compound with the structure shown in the following formula II:

R_f1O(CF₂CF₂O)_m(CF₂O)_nR_f2formula II

In the formula II, m and n are integers, m is more than or equal to 1, preferably m is 1-100, such as 15, 30 and 60; n is more than or equal to 1, preferably n is 1-50, such as 6, 10 and 30; r_f1And R_f2Independently selected from-CF₃、-C₂F₅or-C₃F₇。

In the components of the lubricating grease provided by the invention, the perfluoro base oil can adopt perfluoro base oil with a structure shown in formula I, and also can comprise perfluoro base oil with a structure shown in formula II, wherein the perfluoro base oil accounts for 52-80% of the components of the lubricating grease by weight percent.

In some preferred embodiments, the thickener in the grease of the present invention is selected from one or more of polytetrafluoroethylene, chlorotrifluoroethylene-polyethylene copolymer, or tetrafluoroethylene-hexafluoropropylene copolymer; further preferred is polytetrafluoroethylene. As the thickener, commercially available products such as ZH-4TS, Dongguan Bolin XM220, Zhejiang Quzhou omnida technologies, Inc., and JTC-303S, which are new materials from Australian province in Huangshan, can be used. In other preferred embodiments, the particle size of the thickener is 0.1 to 200 μm, preferably 0.1 to 50 μm, such as 2 μm, 50 μm; so that the obtained lubricating grease has excellent thermal stability and oxidation stability, and is more suitable for working conditions with severe conditions, such as strong acid and strong alkali working conditions.

In some preferred embodiments, the additive in the grease of the present invention is selected from one or more of graphite, silica, molybdenum disulfide, or bentonite; preferably silica. The additive in the present invention may be a commercially available product, for example, Kenyin chemical R972.

The second aspect of the present invention provides a preparation method of perfluoropolyether type lubricating grease, comprising the following steps:

1) emulsifying perfluoro base oil, a thickening agent and an additive under stirring to obtain an ointment;

2) vacuumizing the ointment to obtain the perfluoropolyether lubricating grease; preferably, the vacuuming treatment is carried out until no bubbles are generated on the surface of the ointment, and the vacuuming treatment is stopped.

In the preparation method of the invention, the perfluoro base oil, the thickening agent and the additive are placed in a vacuum emulsification stirrer according to the weight percentage, and stirring is started until the mixture is uniformly stirred, for example, the mixture is stirred until the mixture is in a white oil paste shape; the stirring speed is 100-3000 rpm, and the stirring time is 1-4 h, so as to ensure the full mixing effect of the components, for example, the stirring speed is 150rmp and 2000rmp, and the stirring time is 1h and 2 h.

In the step 2) of the preparation method, the ointment obtained in the step 1) is vacuumized until no bubbles are generated on the surface of the ointment, and then the process is stopped; in some specific embodiments, the vacuum treatment is performed at a vacuum degree of 100 to 10000Pa, preferably 100 to 1000 Pa; the temperature of the vacuumizing treatment is 60-90 ℃, and preferably 70-80 ℃; for example, the obtained ointment is subjected to vacuum treatment at vacuum degree of 2000Pa and 4000Pa, the temperature of the vacuum treatment is 72 ℃, the temperature is 78 ℃, and the temperature is kept for 4 hours and 4.5 hours.

In some preferred embodiments, the ointment is subjected to vacuum pumping treatment and then is subjected to heat preservation for 2-8 hours, preferably 3-5 hours.

In some embodiments, the ointment after vacuuming is repeatedly ground to obtain more uniform grease. The above-described grinding operation can be carried out on a grinder, preferably a three-roll grinder, as is well known to those skilled in the art.

By adopting the technical scheme, the method has the following technical effects:

the perfluoropolyether lubricating grease provided by the invention has good compatibility with various acids, alkalis, salts, corrosive gases and strong oxidants, and can achieve the effects of stability and lubrication; meanwhile, the lubricating grease prepared from the perfluorinated base oil has high thermal stability and oxidation stability, and can be suitable for some working conditions with severe conditions.

The preparation method of the perfluoropolyether lubricating grease provided by the invention is simple in process and suitable for industrial production.

Detailed Description

In order to better understand the technical solution of the present invention, the following examples are further provided to illustrate the present invention, but the present invention is not limited to the following examples.