Current-carrying intelligent lubricating coating, current-carrying intelligent lubricating coating and preparation method thereof

Abstract

The present application relates to the technical field of lubricating material, and particularly relates to a current-carrying intelligent lubricating coating, a current-carrying intelligent lubricating coating and a preparation method thereof.The current-carrying intelligent lubricating coating is prepared from the following raw materials in parts by mass: 40-50 parts of a base material, 5-8 parts of a conductive material, 4-8 parts of an oil-carrying polypyrrole micro storage body and 8-12 parts of a curing agent; the base material is selected from at least one of epoxy resin, phenol-formaldehyde resin, polyurethane and polyimide. The current-carrying intelligent lubricating coating of the present application utilizes the electrical response characteristics of the oil-carrying polypyrrole micro storage body to expand and shrink the pore volume under different current stimuli, so as to regulate the pore size and extrude the internal space of the micro storage body microspheres, thereby realizing the controllable release of the internal lubricating oil.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lubricating materials, in particular to a current-carrying intelligent lubricating coating, a current-carrying intelligent lubricating coating and a preparation method thereof. BACKGROUND

[0002] The friction behavior of two surfaces under the electrified state is called current-carrying friction. Current-carrying friction has important applications in various industries such as aerospace, rail transportation, communication, and power. Current-carrying friction and wear problems are one of the important factors that restrict the service life and reliability of related equipment. Current-carrying self-lubricating coating is a functional coating that combines electrical conductivity, wear resistance, and low friction, and is widely used in the surface performance improvement of high-end equipment sliding electrical contact components.

[0003] Traditional conductive lubricating coatings have basic electrical conductivity and lubrication performance, but have significant limitations in lubrication regulation. On the one hand, the lubrication performance is often difficult to adjust according to the changes in actual working conditions, such as different mechanical running speeds and load sizes, and can usually only provide a fixed lubrication effect, which cannot meet the needs of complex and variable working environments. On the other hand, when facing changes in current size, traditional conductive coatings cannot effectively control the lubrication degree. When the current fluctuates, the lubrication performance of the coating cannot change accordingly, which may cause increased friction and accelerated wear during equipment operation, seriously affecting the service life and working efficiency of the equipment. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application aims to provide a current-carrying intelligent lubricating coating, a current-carrying intelligent lubricating coating and a preparation method thereof, to solve the problem that the existing conductive lubricating coating cannot flexibly adjust the lubrication effect according to the working conditions.

[0005] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0006] The present application provides a current-carrying intelligent lubricating coating, and the preparation raw materials thereof include, in terms of mass fraction: 40-50 parts of a matrix material, 5-8 parts of a conductive material, 4-8 parts of an oil-carrying polypyrrole micro storage body, and 8-12 parts of a curing agent; the matrix material is selected from at least one of epoxy resin, phenolic resin, polyurethane, and polyimide.

[0007] The current-carrying intelligent lubricating coating, wherein the conductive material is selected from at least one of liquid metal, carbon fiber, graphene, and carbon nanotube.

[0008] The current-carrying intelligent lubricating coating, wherein the oil-carrying polypyrrole micro storage body includes polypyrrole hollow microspheres and lubricating oil stored in the polypyrrole hollow microspheres.

[0009] The current application further provides the current application, wherein the curing agent is selected from diaminodiphenyl methane, diaminodiphenyl sulfone or m-phenylenediamine.

[0010] The current application further provides the current application, wherein the lubricating oil comprises at least one of ionic liquid and PAO.

[0011] The current application further provides the current application, wherein the preparation method of the oil-loaded polypyrrole micro storage body comprises the following steps: mixing polystyrene solid microspheres and polyvinylpyrrolidone in a solution and ultrasonic treatment; adding an oxidizing agent and pyrrole to initiate a polymerization reaction, and after the reaction, centrifuging, washing and drying to obtain PS@PPy solid microspheres; soaking the PS@PPy solid microspheres in tetrahydrofuran, continuously stirring to dissolve styrene, and after centrifugal washing, obtaining hollow porous PPy microspheres; and mixing the PPy hollow microspheres and ionic liquid thoroughly, placing them in a negative pressure container and continuously stirring to make the ionic liquid enter the PPy hollow microspheres, and after washing and drying, obtaining the oil-loaded polypyrrole micro storage body.

[0012] The current application further provides the current application, wherein the mixing of the polystyrene solid microspheres and polyvinylpyrrolidone in a solution and ultrasonic treatment specifically comprises: mixing the polystyrene solid microspheres and polyvinylpyrrolidone in an ethanol aqueous solution, and then ultrasonic treatment at 25-30℃ for 4-5 hours.

[0013] The current application further provides the current application, wherein the particle size of the oil-loaded polypyrrole micro storage body is 1-2 microns.

[0014] The current application further provides the current application, wherein the oil-loaded polypyrrole micro storage body is prepared by the method.

[0015] The current application further provides the current application, wherein the preparation method of the oil-loaded polypyrrole micro storage body comprises the following steps: mixing polystyrene solid microspheres and polyvinylpyrrolidone in a solution and ultrasonic treatment; adding an oxidizing agent and pyrrole to initiate a polymerization reaction, and after the reaction, centrifuging, washing and drying to obtain PS@PPy solid microspheres; soaking the PS@PPy solid microspheres in tetrahydrofuran, continuously stirring to dissolve styrene, and after centrifugal washing, obtaining hollow porous PPy microspheres; and mixing the PPy hollow microspheres and ionic liquid thoroughly, placing them in a negative pressure container and continuously stirring to make the ionic liquid enter the PPy hollow microspheres, and after washing and drying, obtaining the oil-loaded polypyrrole micro storage body.

[0016] The current application further provides the current application, wherein the particle size of the oil-loaded polypyrrole micro storage body is 1-2 microns. DETAILED DESCRIPTION

[0017] The present application provides a current-carrying intelligent lubricating coating, a current-carrying intelligent lubricating coating and a preparation method thereof. In order to make the purpose, technical scheme and effect of the present application more clear and explicit, the present application will be further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0018] The present application provides a current-carrying intelligent lubricating coating, a current-carrying intelligent lubricating coating and a preparation method thereof. In order to make the purpose, technical scheme and effect of the present application more clear and explicit, the present application will be further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application. The current-carrying intelligent lubricating coating of the present application comprises: 40-50 parts of a base material, 5-8 parts of a conductive material, 4-8 parts of an oil-carrying polypyrrole micro storage body and 8-12 parts of a curing agent. The base material is selected from at least one of epoxy resin, phenolic resin, polyurethane and polyimide. The oil-carrying polypyrrole micro storage body used in the present application is a polypyrrole microsphere which stores lubricating oil inside. Under electrical stimulation, the polymer polypyrrole shell will undergo redox reaction, resulting in the expansion or contraction of the pore volume, so that the release efficiency of the internal ionic liquid will be regulated by electrical stimulation, and the lubricating effect will be flexibly adjusted according to the working condition. In order to improve the response rate of the coating, the present application further adds a conductive material to the coating to improve the conductivity of the coating.

[0019] Preferably, the conductive material is selected from at least one of liquid metal, carbon fiber, graphene and carbon nanotube. These conductive materials not only have conductivity, but also have lubricating effect, which can reduce the friction coefficient and reduce wear.

[0020] Preferably, the curing agent is selected from diaminodiphenylmethane, diaminodiphenyl sulfone or m-phenylenediamine.

[0021] Preferably, the lubricating oil comprises at least one of ionic liquid and PAO. The ionic liquid itself is composed of anions and cations, has certain conductivity and is beneficial to release and migration under electrical stimulation.

[0022] Preferably, the preparation method of the oil-carrying polypyrrole micro storage body comprises the following steps: mixing polystyrene solid microspheres and polyvinylpyrrolidone in a solution and ultrasonic treatment; adding an oxidizing agent and pyrrole to initiate polymerization reaction, and after reaction, centrifuging, washing and drying to obtain PS@PPy solid microspheres; soaking the PS@PPy solid microspheres in tetrahydrofuran and continuously stirring to dissolve styrene, and after centrifuging and washing, obtaining hollow porous PPy microspheres; mixing the PPy hollow microspheres and ionic liquid thoroughly and placing them in a negative pressure container for continuous stirring, so that the ionic liquid enters the PPy hollow microspheres, and after washing and drying, the oil-carrying polypyrrole micro storage body is obtained. Specifically, the polystyrene solid microspheres can be prepared by emulsion polymerization, suspension polymerization or obtained by commercial channels.

[0023] Preferably, the polystyrene solid microspheres and the polyvinylpyrrolidone are mixed in a solution, and ultrasonic treatment is performed, specifically including: the polystyrene solid microspheres and the polyvinylpyrrolidone are mixed in 30-60 wt% ethanol aqueous solution, and then ultrasonic treatment is performed at 25-30℃ for 4-5 hours.

[0024] Preferably, the particle size of the oil-loaded polypyrrole micro storage body is 1-2 microns. If the particle size of the oil-loaded polypyrrole micro storage body is too large, it is not conducive to forming a multilayer distribution in the coating.

[0025] The second aspect of the present application provides a current-carrying intelligent lubricating coating prepared from the current-carrying intelligent lubricating coating as described above. The current-carrying intelligent lubricating coating prepared by the present application has a low friction coefficient in the current-carrying friction performance test, and the friction coefficient changes according to the current change, specifically, the larger the current, the smaller the friction coefficient, which can effectively cope with the changing working conditions of the conductive equipment.

[0026] The third aspect of the present application provides a preparation method of a current-carrying intelligent lubricating coating, which is used to prepare the current-carrying intelligent lubricating coating as described above, and includes the following steps: mixing a base material, a conductive material and an oil-loaded polypyrrole micro storage body, adding a curing agent, uniformly stirring, and then vacuum treatment to obtain a coating; coating the coating on a substrate, and curing to obtain the current-carrying intelligent lubricating coating.

[0027] Example 1

[0028] A current-carrying intelligent lubricating coating, and a preparation method thereof includes the following steps:

[0029] S01. Preparation of an oil-loaded polypyrrole (PPy) micro storage body:

[0030] Polystyrene solid microspheres (PS solid microspheres) with a particle size of 1-2 microns are selected, 0.6g of the PS solid microspheres and 0.1g of polyvinylpyrrolidone (PNVP, stabilizer) are mixed in 30mL of 60wt% ethanol aqueous solution, and the mixed liquid sample is subjected to ultrasonic treatment at 30℃ for 4 hours;

[0031] Then, 1.6g of FeCl3·6H2O (oxidizing agent) is added, and 250μL of pyrrole with a concentration of 98wt% is added to initiate polymerization, and the reaction lasts for 24 hours. After the reaction, the sample is washed by centrifugation with deionized water for three times, and then dried at 60℃ for 12 hours to obtain black powder-like PS@PPy solid microspheres;

[0032] 10mg of the PS@PPy solid microspheres are placed in 20mL of tetrahydrofuran (THF), and stirred and dissolved at 25℃ for 24 hours; then, the hollow PPy micro storage body is separated by centrifugation, washed with ethanol for three times, and then the sample is dried at 50℃ for 12 hours;

[0033] A certain amount of hollow PPy micro storage body and ionic liquid (lubricating oil) are mixed well, and placed in a negative pressure sealing device to make the hollow PPy micro storage body adsorb the ionic liquid; after adsorption for 48 h, the oil-loaded polypyrrole micro storage body is obtained, filtered and separated, and the surface ionic liquid is removed;

[0034] S02. Preparation of a current-carrying intelligent lubricating coating:

[0035] 40 parts of epoxy resin (E51), 2 parts of carbon fiber, 3 parts of graphene, and 4 parts of oil-loaded polypyrrole micro storage body are mixed and stirred for 10 min to fully mix; 10 parts of diamino diphenyl methane curing agent (DDM) is added, and further stirred for 10 min before being placed in a vacuum device to eliminate bubbles, to obtain a current-carrying intelligent lubricating coating;

[0036] The prepared current-carrying intelligent lubricating coating is dropped on a stainless steel round pad adsorbed on a glue spreading machine, the rotating speed of the glue spreading machine is adjusted to 500 rpm for 30 s first, and then 600 rpm for 30 s, so that the current-carrying intelligent lubricating coating is uniformly dispersed on the surface of the steel plate, and finally, the current-carrying intelligent lubricating coating is cured in an oven at 60°C for 6 h to obtain a current-carrying intelligent lubricating coating.

[0037] Example 2

[0038] A current-carrying intelligent lubricating coating, the difference between the preparation method thereof and that of Example 1 is that the formula of the current-carrying intelligent lubricating coating is different, and in this embodiment, the raw materials for preparing the current-carrying intelligent lubricating coating are composed of 40 parts of epoxy resin (E51), 2 parts of carbon fiber, 3 parts of graphene, 8 parts of oil-loaded polypyrrole micro storage body, and 10 parts of diamino diphenyl methane curing agent (DDM).

[0039] Example 3

[0040] A current-carrying intelligent lubricating coating, the difference between the preparation method thereof and that of Example 1 is that the formula of the current-carrying intelligent lubricating coating is different, and in this embodiment, the raw materials for preparing the current-carrying intelligent lubricating coating are composed of 40 parts of epoxy resin (E51), 2 parts of liquid metal, 3 parts of graphene, 4 parts of oil-loaded polypyrrole micro storage body, and 10 parts of diamino diphenyl methane curing agent (DDM).

[0041] Example 4

[0042] A current-carrying intelligent lubricating coating, the difference between the preparation method thereof and that of Example 1 is that the formula of the current-carrying intelligent lubricating coating is different, and in this embodiment, the raw materials for preparing the current-carrying intelligent lubricating coating are composed of 40 parts of epoxy resin (E51), 2 parts of liquid metal, 2 parts of carbon fiber, 2 parts of graphene, 6 parts of oil-loaded polypyrrole micro storage body, and 10 parts of diamino diphenyl methane curing agent (DDM).

[0043] Example 5

[0044] A current-carrying intelligent lubricating coating, the difference between the preparation method and embodiment 1 is that the formula of the current-carrying intelligent lubricating coating is different, in this embodiment, the raw materials for preparing the current-carrying intelligent lubricating coating are composed of 50 parts of phenolic resin, 2 parts of liquid metal, 3 parts of graphene, 6 parts of oil-loaded polypyrrole micro storage body and 10 parts of diaminodiphenyl methane curing agent (DDM).

[0045] The curing temperature of the current-carrying intelligent lubricating coating is 180℃, and the curing time is 2h.

[0046] Comparative example 1

[0047] A lubricating coating, the difference between the preparation method and embodiment 1 is that the raw materials for preparing the lubricating coating are composed of 40 parts of epoxy resin (E51), 2 parts of carbon fiber, 3 parts of graphene and 10 parts of diaminodiphenyl methane curing agent (DDM).

[0048] Comparative example 2

[0049] A lubricating coating, the difference between the preparation method and embodiment 1 is that the raw materials for preparing the lubricating coating are composed of 40 parts of epoxy resin (E51), 4 parts of oil-loaded polypyrrole micro storage body and 10 parts of diaminodiphenyl methane curing agent (DDM).

[0050] Test the current-carrying friction performance of the coating prepared in each of the above embodiments and comparative examples in the atmospheric environment: test the change of the friction coefficient of the prepared coating under the conditions of 0, 0.5, 1A current by using UMT ball-on-disc friction and wear tester. The friction pair is GCr15 steel ball, the current is output from the positive electrode of the direct current power supply, and then input to the negative electrode through the sliding resistor, the coating and the steel ball pair. Reciprocating sliding friction mode is adopted, and the experimental parameters are respectively normal load 10N, frequency 2Hz, stroke 5mm, 20min. The test results are shown in Table 1.

[0051] Table 1. Friction coefficient of lubricating coating in current-carrying environment

[0052]

[0053] From the above results, it can be seen that the friction coefficients of Examples 1-4 are significantly reduced after power-on, and the reduction amplitude increases with the increase of current, which is mainly due to the redox reaction of the PPy shell of the oil-loaded polypyrrole micro-reservoir under electrical stimulation, resulting in the change of the expansion or contraction amplitude of the PPy shell. Under different current stimulation, the oil-loaded polypyrrole micro-reservoir controls the ion liquid release by regulating the pore size and extruding the internal space of the microsphere through the cycle process of expansion / contraction, thereby realizing intelligent lubrication. Comparative Example 1 added conductive materials, but did not have an electric response micro-reservoir, and the friction coefficient slightly decreased after power-on, with small changes, which may be due to the internal electric field change after power-on. Comparative Example 2 added an electric response micro-reservoir, but did not add conductive fillers, and the coating had poor conductivity, thereby affecting the stimulation effect of the electric response micro-reservoir, and the friction coefficient only slightly decreased.

[0054] Among them, Example 4 has a smaller friction coefficient than Example 2, although the amount of oil-loaded polypyrrole micro-reservoir is less, but in the case of more conductive materials, which shows that the amount of oil-loaded polypyrrole micro-reservoir needs to reach a suitable proportion with the conductive materials, in order to achieve the best effect.

[0055] It can be understood that for those skilled in the art, equivalent replacements or changes can be made according to the technical solutions and inventive concepts of the present application, and all such changes or replacements shall fall within the protection scope of the appended claims of the present application.

Claims

1. A current-carrying smart lubricating coating, characterized in that, The preparation raw material comprises, by mass fraction, 40-50 parts of a matrix material, 5-8 parts of a conductive material, 4-8 parts of an oil-loaded polypyrrole micro storage body, and 8-12 parts of a curing agent; the matrix material is selected from at least one of epoxy resin, phenol formaldehyde resin, polyurethane and polyimide; the oil-loaded polypyrrole micro storage body comprises polypyrrole hollow microspheres and ionic liquid stored in the polypyrrole hollow microspheres; The preparation method of the oil-loaded polypyrrole micro storage body comprises the following steps: mixing polystyrene solid microspheres and polyvinylpyrrolidone in a solution and ultrasonic treatment; adding an oxidant and pyrrole to initiate a polymerization reaction, and obtaining PS@PPy solid microspheres after centrifugation, cleaning and drying; immersing the PS@PPy solid microspheres in tetrahydrofuran, continuously stirring to dissolve polystyrene, and obtaining hollow porous PPy microspheres after centrifugation and cleaning; mixing the PPy hollow microspheres and ionic liquid thoroughly, placing them in a negative pressure container and continuously stirring to make the ionic liquid enter the PPy hollow microspheres, and obtaining the oil-loaded polypyrrole micro storage body after cleaning and drying.

2. The current-carrying intelligent lubricating coating of claim 1, wherein, The conductive material is selected from at least one of liquid metal, carbon fiber, graphene and carbon nanotube.

3. The current-carrying intelligent lubricating coating of claim 1, wherein, The curing agent is selected from diaminodiphenylmethane, diaminodiphenyl sulfone or m-phenylenediamine.

4. The current-carrying intelligent lubricating coating of claim 1, wherein, The mixing of the polystyrene solid microspheres and polyvinylpyrrolidone in a solution and ultrasonic treatment specifically comprises mixing the polystyrene solid microspheres and polyvinylpyrrolidone in an ethanol aqueous solution, and then ultrasonic treatment at 25-30°C for 4-5 hours.

5. The current-carrying intelligent lubricating coating of claim 1, wherein, The particle size of the oil-loaded polypyrrole micro storage body is 1-2 microns.

6. A current-carrying intelligent lubricating coating characterized by, The current-carrying intelligent lubricating coating is prepared by the method.

7. A method for the preparation of a current-carrying smart lubricating coating for the preparation of a current-carrying smart lubricating coating according to claim 6, characterized in that The method comprises the following steps: mixing the matrix material, the conductive material and the oil-loaded polypyrrole micro storage body thoroughly, adding the curing agent, uniformly stirring and then vacuum treatment to obtain the current-carrying intelligent lubricating coating; coating the current-carrying intelligent lubricating coating on a substrate, curing to obtain the current-carrying intelligent lubricating coating.

Images