Phosphate amine salt conductive lubricating grease as well as preparation method and application thereof

Abstract

The invention provides phosphate amine salt conductive lubricating grease as well as a preparation method and application thereof. The conductive lubricating grease comprises the following components in percentage by mass: 5-20% of oil-soluble ionic liquid, 1-15% of a thickening agent and the balance of base oil, the oil-soluble ionic liquid is phosphate amine salt ionic liquid obtained by reacting lauryl amine with diisooctyl phosphate. The preparation method comprises the following steps: preparing an oil-soluble ionic liquid, mixing, saponifying and refining to obtain the phosphate amine salt conductive lubricating grease. The preparation of the phosphate amine salt conductive lubricating grease is realized.

Description

Technical Field

[0001] The present application relates to the technical field of lubricating materials, and in particular to a phosphate amine salt conductive grease and a preparation method and application thereof. Background Art

[0002] The rapid development of modern industry has accelerated the excessive consumption of energy. Friction will cause wear of mechanical equipment and additional energy consumption. The use of grease is the most effective means to reduce friction, reduce or avoid wear. They are widely used in almost all industries, aerospace, electronic information industry and various military equipment. However, in some special working conditions, such as transformer equipment, pantographs, ultra-high voltage transmission lines and other equipment, the grease not only needs to have good lubrication properties, but also good electrical conductivity.

[0003] Conductive grease is a new type of electrical lubricating material. The base oil used to prepare conductive grease is usually silicone oil, mineral oil and synthetic lipid oil. A series of additives such as conductivity, corrosion resistance and antioxidant are added according to specific conductive requirements. It is prepared through a series of processes such as grinding, dispersion and modification. It looks like a soft paste.

[0004] In the prior art, metal powders such as gold powder and silver powder are usually added to grease as conductive fillers. However, the high prices of gold powder and silver powder limit their application scope. Tin powder is easily oxidized, resulting in poor stability of the grease. Summary of the invention

[0005] The present application provides a phosphate amine salt conductive grease and a preparation method and application thereof, in order to solve the above-mentioned problems mentioned in the background technology.

[0006] On the one hand, the present application provides a phosphate amine salt conductive grease, which comprises the following components in mass percentage: 5-20% of oil-soluble ionic liquid, 1-15% of thickener and the balance of base oil;

[0007] The oil-soluble ionic liquid is a phosphate amine salt ionic liquid obtained by the reaction of dodecylamine and diisooctyl phosphate.

[0008] Optionally, the structural formula of the oil-soluble ionic liquid is as follows:

[0009]

[0010] Optionally, the thickener is dodecyl hydroxystearic acid.

[0011] Optionally, the base oil is any one of PEC100, base oil PAO10 or base oil 5750.

[0012] On the other hand, the present application also provides a method for preparing a phosphate amine salt conductive grease, which is used to prepare the above-mentioned phosphate amine salt conductive grease, and the preparation method comprises the following steps:

[0013] (1) Preparation of oil-soluble ionic liquid: weigh dodecylamine and diisooctyl phosphate, stir and mix, and react to obtain an oil-soluble ionic liquid;

[0014] (2) Mixing: weighing the base oil, the oil-soluble ionic liquid and the thickener according to mass percentage, stirring and mixing, and performing a saponification reaction to obtain a saponification reaction liquid;

[0015] (3) Refining: The saponification reaction liquid is heated and refined under stirring to obtain phosphate amine salt conductive grease.

[0016] Optionally, the molar ratio of dodecylamine to diisooctyl phosphate is 1.1-1.2:1.

[0017] Optionally, in the step of preparing the oil-soluble ionic liquid, the reaction temperature is 50-80° C. and the reaction time is 8-24 h.

[0018] Optionally, the saponification reaction temperature is 80-120° C., and the reaction time is 30-60 min.

[0019] Optionally, in the refining step, the reaction temperature is 100-120°C and the reaction time is 10-30 minutes.

[0020] On the other hand, a phosphate amine salt conductive grease is used, and the phosphate amine salt conductive grease is the above-mentioned phosphate amine salt conductive grease, or the phosphate amine salt conductive grease prepared by the above-mentioned preparation method, and the phosphate amine salt conductive grease is used as a lubricating material.

[0021] The phosphate amine salt conductive grease and its preparation method and application provided in the present application realize the preparation of the phosphate amine salt conductive grease, and have the following beneficial effects compared with the prior art:

[0022] (1) By adding 5-20% by weight of oil-soluble ionic liquid and 1-15% of thickener to the base oil. In the present application, the oil-soluble ionic liquid is one of the components of the conductive grease. The anions and cations in the oil-soluble ionic liquid can move in a directional manner under the action of the electric field, giving the grease good conductivity; at the same time, the oil-soluble ionic liquid itself has good lubrication properties, which can further improve the tribological properties and extreme pressure and anti-wear properties of the conductive grease. The thickener can form a structural skeleton in the base oil, which is conducive to the conductive grease to better adhere to the surface of the metal friction pair, and helps to improve the lubrication properties of the conductive grease. And the conductive grease provided in the present application is expected to play a role in long-term lubrication and continuous conductivity at the metal conductor connections of power plants, substations, distribution stations and high-voltage transmission lines.

[0023] (2) Dodecyl hydroxystearic acid is used to form a soap thickener in the conductive grease. Dodecyl hydroxystearic acid has good lipophilicity and can be evenly mixed with the base oil and the oil-soluble ionic liquid, which helps the base oil and the oil-soluble ionic liquid to be adsorbed and fixed in the structural skeleton of the soap thickener, thereby enhancing the consistency and adhesion of the conductive grease, which is beneficial for the conductive grease to better adhere to the surface of the metal friction pair, and helps to improve the lubrication performance of the conductive grease.

[0024] (3) The preparation process of the present application is simple, and the obtained conductive grease has good conductivity and lubrication properties, and is suitable for promotion. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application is clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work also fall within the scope of protection of the present application.

[0026] On the one hand, the present application provides a phosphate amine salt conductive grease, which comprises the following components in mass percentage: 5-20% of oil-soluble ionic liquid, 1-15% of thickener and the balance of base oil;

[0027] The oil-soluble ionic liquid is a phosphate amine salt ionic liquid obtained by the reaction of dodecylamine and diisooctyl phosphate.

[0028] Optionally, the structural formula of the oil-soluble ionic liquid is as follows:

[0029]

[0030] Specifically, the phosphate amine salt conductive grease provided by the present application includes an oil-soluble ionic liquid, a thickener and a base oil, wherein the base oil plays a main lubricating role, maintains the friction reduction and anti-wear performance of the conductive grease, and the oil-soluble ionic liquid plays a main conductive role. The anions and cations in the oil-soluble ionic liquid can move in a directional manner under the action of the electric field, giving the grease good conductivity. At the same time, the oil-soluble ionic liquid itself has good lubrication properties, which can further improve the tribological properties and extreme pressure anti-wear properties of the conductive grease. The thickener can be dispersed in the base oil and form a structural skeleton, so that the base oil is adsorbed and fixed in the structural skeleton, thereby forming a semi-solid grease with plasticity, which is conducive to the conductive grease to better adhere to the surface of the metal friction pair, and helps to improve the lubrication performance of the conductive grease.

[0031] The present application provides a conductive grease with good electrical conductivity and anti-friction and anti-wear properties through the above scheme. By adding 5-20% by mass of oil-soluble ionic liquid and 1-15% of thickener to the base oil. In the present application, the oil-soluble ionic liquid is used as one of the components of the conductive grease. The anions and cations in the oil-soluble ionic liquid move in a directional manner under the action of the electric field, giving the grease good electrical conductivity; at the same time, the oil-soluble ionic liquid itself has good lubrication properties, which can further improve the tribological properties and extreme pressure anti-wear properties of the conductive grease. The thickener can form a structural skeleton in the base oil, which is conducive to the conductive grease to better adhere to the surface of the metal friction pair, and helps to improve the lubrication properties of the conductive grease. And the conductive grease provided by the present application is expected to play a role in long-term lubrication and continuous conductivity at the metal conductor connections of power plants, substations, distribution stations and high-voltage transmission lines.

[0032] Optionally, the thickener is dodecyl hydroxystearic acid.

[0033] Specifically, dodecyl hydroxystearic acid can form a soap thickener in the conductive grease. At the same time, dodecyl hydroxystearic acid has good lipophilicity and can be evenly mixed with the base oil and oil-soluble ionic liquid, which helps the base oil and the oil-soluble ionic liquid to be adsorbed and fixed in the structural skeleton of the soap thickener, thereby enhancing the consistency and adhesion of the conductive grease, which is beneficial for the conductive grease to better adhere to the surface of the metal friction pair, and helps to improve the lubrication performance of the conductive grease.

[0034] Optionally, the base oil is any one of PEC100, base oil PAO10 or base oil 5750.

[0035] Specifically, the above-mentioned base oils are all commonly used base oils, which can be purchased commercially and are easy to use.

[0036] On the other hand, the present application also provides a method for preparing a phosphate amine salt conductive grease, which is used to prepare the above-mentioned phosphate amine salt conductive grease, and the preparation method comprises the following steps:

[0037] (1) Preparation of oil-soluble ionic liquid: weigh dodecylamine and diisooctyl phosphate, stir and mix, and react to obtain an oil-soluble ionic liquid;

[0038] (2) Mixing: weighing the base oil, the oil-soluble ionic liquid and the thickener according to mass percentage, stirring and mixing, performing a saponification reaction, and obtaining a saponification reaction liquid;

[0039] (3) Refining: The saponification reaction liquid is heated and refined under stirring to obtain phosphate amine salt conductive grease.

[0040] Specifically, an oil-soluble ionic liquid is first synthesized by using dodecylamine and diisooctyl phosphate, and then the base oil, the oil-soluble ionic liquid and the thickener are stirred and mixed to perform a saponification reaction, thereby forming a soap thickener in the conductive grease, which helps the base oil and the oil-soluble ionic liquid to be adsorbed and fixed in the structural skeleton of the soap thickener, thereby enhancing the adhesion of the conductive grease and helping to improve the lubrication performance of the conductive grease. The saponification reaction liquid is heated and refined under stirring, and during the refining process, the viscosity of the grease system is reduced, and it is transformed from a grease state to a viscous liquid, thereby obtaining a phosphate amine salt conductive grease.

[0041] Furthermore, after the refining is completed, the obtained phosphate amine salt conductive grease is naturally cooled to room temperature and then ground so that the soap thickener and the oil-soluble ionic liquid therein are evenly dispersed in the base oil to obtain a homogeneous conductive grease, which is conducive to forming a homogeneous and stable lubricating film on the surface of the metal friction pair during the friction process, improving the friction reduction and anti-wear performance, and at the same time, it is conducive to the uniform dispersion of the oil-soluble ionic liquid, thereby improving the conductive performance of the conductive grease. Preferably, the grinding is performed by a three-roll mill.

[0042] Optionally, the molar ratio of dodecylamine to diisooctyl phosphate is 1:1-1.1. More preferably, the molar ratio of dodecylamine to diisooctyl phosphate is 1:1.

[0043] Optionally, in the step of preparing the oil-soluble ionic liquid, the reaction temperature is 50-80°C and the reaction time is 8-24h. Further, the reaction temperature is 60-70°C, and further the reaction temperature is 65°C and the reaction time is 12-24h.

[0044] Optionally, the saponification reaction temperature is 80-120°C, and the reaction time is 30-60 min. Furthermore, the saponification reaction temperature is 120°C, and the reaction time is 40-60 min.

[0045] Optionally, in the refining step, the reaction temperature is 100-120°C and the reaction time is 10-30 min.

[0046] More preferably 15-25 minutes

[0047] On the other hand, a phosphate amine salt conductive grease is used, and the phosphate amine salt conductive grease is the above-mentioned phosphate amine salt conductive grease, or the phosphate amine salt conductive grease prepared by the above-mentioned preparation method, and the phosphate amine salt conductive grease is used as a lubricating material.

[0048] The following are embodiments and effect test examples of the present application, and the technical scheme and technical effect of the present invention are further described, but the protection scope of the present invention is not limited to these embodiments. Any changes or equivalent substitutions that do not deviate from the concept of the present invention are within the protection scope of the present invention. In addition, those who do not indicate specific technical operation steps or conditions in the embodiments are all carried out according to the technology or conditions described in the general literature in this area or according to the product specification. Those who do not indicate the manufacturer of reagents or instruments used are all conventional products that can be obtained by commercial purchase.

[0049] Example 1

[0050] A method for preparing a phosphate amine salt conductive grease comprises the following steps:

[0051] (1) Preparation of oil-soluble ionic liquid: Weigh dodecylamine and diisooctyl phosphate, stir and mix them, and react at 50° C. for 8 h to obtain an oil-soluble ionic liquid; wherein the molar ratio of dodecylamine to diisooctyl phosphate is 1:1.

[0052] (2) Mixing: 83 g of PEC base oil was weighed by mass percentage, and preheated at 80° C. for 30 min under mechanical stirring. 10 g of the oil-soluble ionic liquid in (1) was weighed and added to the preheated PEC base oil under stirring. Then 7 g of dodecyl hydroxyhard acid was weighed and slowly added to the stirred PEC base oil. After the addition was completed, stirring was continued at 80° C. for 30 min to carry out saponification reaction, so that the thickener was completely dissolved, and a saponification reaction liquid was obtained.

[0053] (3) Refining: The saponification reaction liquid is heated and refined at 100° C. for 10 min under stirring to obtain a phosphate amine salt conductive grease.

[0054] (4) Grinding: After the grease system is naturally cooled to room temperature, the phosphate amine salt conductive grease is ground for 20 minutes using a three-roll mill to finally obtain a homogeneous phosphate amine salt conductive grease.

[0055] Example 2

[0056] A method for preparing a phosphate amine salt conductive grease comprises the following steps:

[0057] (1) Preparation of oil-soluble ionic liquid: Weigh dodecylamine and diisooctyl phosphate, stir and mix them, and react at 65° C. for 16 h to obtain an oil-soluble ionic liquid; wherein the molar ratio of dodecylamine to diisooctyl phosphate is 1:1.

[0058] (2) Mixing: 80 g of PEC base oil was weighed by mass percentage, and preheated at 100° C. for 30 min under mechanical stirring. 10 g of the oil-soluble ionic liquid in (1) was weighed and added to the preheated PEC base oil under stirring. Then 7 g of dodecyl hydroxyhard acid was weighed and slowly added to the stirred PEC base oil. After the addition was completed, stirring was continued at 100° C. for 40 min to carry out a saponification reaction, so that the thickener was completely dissolved, and a saponification reaction liquid was obtained.

[0059] (3) Refining: The saponification reaction liquid is heated and refined at 110° C. for 15 min under stirring to obtain a phosphate amine salt conductive grease.

[0060] (4) Grinding: After the grease system is naturally cooled to room temperature, the phosphate amine salt conductive grease is ground for 20 minutes using a three-roll mill to finally obtain a homogeneous phosphate amine salt conductive grease.

[0061] Example 3

[0062] A method for preparing a phosphate amine salt conductive grease comprises the following steps:

[0063] (1) Preparation of oil-soluble ionic liquid: Weigh dodecylamine and diisooctyl phosphate, stir and mix them, and react at 80°C for 24 hours to obtain an oil-soluble ionic liquid; wherein the molar ratio of dodecylamine to diisooctyl phosphate is 1:1.1.

[0064] (2) Mixing: 80 g of PEC base oil was weighed by mass percentage, and preheated at 120° C. for 30 min under mechanical stirring. 10 g of the oil-soluble ionic liquid in (1) was weighed and added to the preheated PEC base oil under stirring. Then 7 g of dodecyl hydroxyhard acid was weighed and slowly added to the stirred PEC base oil. After the addition was completed, stirring was continued at 120° C. for 60 min to carry out saponification reaction, so that the thickener was completely dissolved, and a saponification reaction liquid was obtained.

[0065] (3) Refining: The saponification reaction liquid is heated and refined at 120° C. for 30 min under stirring to obtain a phosphate amine salt conductive grease.

[0066] (4) Grinding: After the grease system is naturally cooled to room temperature, the phosphate amine salt conductive grease is ground for 20 minutes using a three-roll mill to finally obtain a homogeneous phosphate amine salt conductive grease.

[0067] Comparative Example 1

[0068] A method for preparing a phosphate amine salt conductive grease comprises the following steps:

[0069] Weigh 90g of PEC base oil, preheat at 80℃ for 30min under mechanical stirring, weigh 10g of dodecyl stearic acid, add it to the preheated PEC base oil while stirring, and continue stirring at 80℃ for 30min after the addition is complete to completely dissolve the thickener. After the grease system is completely cooled, grind the blank grease with a three-roll mill for 20min to finally obtain a blank grease.

[0070] Experimental Example 1

[0071] Tribological properties test of phosphate amine salt conductive grease

[0072] The friction and wear performance of the conductive grease obtained by the technical solutions provided in Examples 1 to 3 and Comparative Example 1 was tested. The friction and wear test was performed using the MS-10A four-ball friction and wear tester produced by Xiamen Tianji Automation Co., Ltd. in accordance with the petrochemical industry standard "SH / T 0202-1992" grease extreme pressure performance determination method (four-ball machine method). The test time was 60 minutes, the speed was 1200 r / min, the steel ball had a diameter of 12.7 mm, the steel ball was GCr15 (SAE52100), and the hardness was 750-850 HV. At least 3 parallel tests were performed for each test, and the average value was taken to obtain the test results shown in Table 1.

[0073] Table 1 Average friction coefficient and average wear spot diameter of the examples

[0074]

[0075] It can be seen from Table 1 that the conductive grease obtained by the technical solutions provided in Examples 1 to 3 has better lubrication performance than that of Comparative Example 1, and the friction reduction and anti-wear properties of the conductive grease are greatly improved.

[0076] Experimental Example 2

[0077] Dropping point and cone penetration test of phosphate amine salt conductive grease

[0078] The conductive grease obtained by the technical solutions provided in Examples 1 to 3 and Comparative Example 1 was tested for dropping point and cone penetration. The test standards are: national standard GB / T4929-1985 grease dropping point determination method and GB / T269-2023 grease and petroleum grease cone penetration determination method. At least 3 parallel tests were performed for each test, and the average value was taken. The results are shown in Table 2.

[0079] Table 2 Dropping point and cone penetration of greases in the examples and comparative examples

[0080]

[0081]

[0082] It can be seen from Table 2 that with the addition of oil-soluble ionic liquid, the dropping point and cone penetration data of the conductive grease are almost unchanged compared with those of Example 1, which proves that the addition of oil-soluble ionic liquid has little effect on the structure and physical and chemical properties of the grease.

[0083] Experimental Example 3

[0084] Maximum non-seizure load and sintering load test of phosphate amine salt conductive grease

[0085] The MS-10A four-ball friction and wear tester produced by Xiamen Tianji Automation Co., Ltd. was used to test the extreme pressure bearing capacity of the greases of the embodiments and comparative examples according to the industry standard "SH / T 0202-1992" lubricating grease extreme pressure performance determination method (four-ball machine method) and the industry standard "SH / T 0204-1992" lubricating grease anti-wear performance determination method (four-ball machine method). The results are shown in Table 3.

[0086] Table 3 PB (maximum non-seizure load) and PD (seizure load) of grease

[0087]

[0088] It can be seen from Table 3 that, compared with Comparative Example 1, the maximum non-seizure load and sintering load of the conductive grease provided in Examples 1 to 3 are significantly improved, indicating that the conductive grease provided in the examples has good extreme pressure bearing performance.

[0089] Experimental Example 4

[0090] Conductive performance test of phosphate amine salt conductive grease

[0091] The electrical conductivity of the greases in the examples and comparative examples was measured using an FT-304 series resistivity tester produced by Ningbo Ruike Instrument Co., Ltd. The results are shown in Table 4.

[0092] Table 4 Conductivity of greases in Examples and Comparative Examples

[0093]

[0094] It can be seen from Table 4 that with the addition of oil-soluble ionic liquid, the volume resistivity of the conductive grease in Examples 1 to 3 is significantly reduced, indicating that the addition of oil-soluble ionic liquid not only improves the tribological properties of the grease, but also greatly improves its conductive properties. When the addition amount is 10% (Example 3), its conductivity is reduced by 2 orders of magnitude compared with the blank grease.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, ordinary technicians in the field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A phosphate amine salt conductive grease, characterized in that: The conductive grease comprises the following components in percentage by mass: 5-20% of oil-soluble ionic liquid, 1-15% of thickener and the remainder of base oil; The oil-soluble ionic liquid is a phosphate amine salt ionic liquid obtained by reacting dodecylamine with diisooctyl phosphate.

2. The phosphate amine salt conductive grease according to claim 1, characterized in that: The oil-soluble ionic liquid has a structure shown in Formula I:

3. The phosphate amine salt conductive grease according to claim 1, characterized in that: The thickener is dodecyl hydroxystearic acid.

4. The phosphate amine salt conductive grease according to claim 1, characterized in that: The base oil is any one of PEC100, base oil PAO10 or base oil 5750.

5. A method for preparing a phosphate amine salt conductive grease, characterized in that: For preparing the phosphate amine salt conductive grease according to any one of claims 1 to 4, the preparation method comprises the following steps: (1) Preparation of oil-soluble ionic liquid: weighing the dodecylamine and the diisooctyl phosphate, stirring and mixing, and reacting to obtain the oil-soluble ionic liquid; (2) mixing: weighing the base oil, the oil-soluble ionic liquid and the thickener according to mass percentage, stirring and mixing, performing a saponification reaction, and obtaining a saponification reaction liquid; (3) Refining: The saponification reaction liquid is heated and refined under stirring to obtain the phosphate amine salt conductive grease.

6. The method for preparing the phosphate amine salt conductive grease according to claim 5, characterized in that: The added molar ratio of the dodecylamine to the diisooctyl phosphate is 1:1-1.

1.

7. The method for preparing the phosphate amine salt conductive grease according to claim 5, characterized in that: In the oil-soluble ionic liquid preparation step, the reaction temperature is 50-80° C. and the reaction time is 8-24 hours.

8. The method for preparing the phosphate amine salt conductive grease according to claim 5, characterized in that: The saponification reaction temperature is 80-120° C., and the reaction time is 30-60 min.

9. The method for preparing the phosphate amine salt conductive grease according to claim 5, characterized in that: In the refining step, the reaction temperature is 100-120° C. and the reaction time is 10-30 min.

10. An application of a phosphate amine salt conductive grease, characterized in that: The phosphate amine salt conductive grease is the phosphate amine salt conductive grease described in any one of claims 1 to 4, or the phosphate amine salt conductive grease prepared by the preparation method described in any one of claims 5 to 9, and the phosphate amine salt conductive grease is used as a lubricating material.

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