A wear-resistant cellulose coating and its preparation method

Abstract

A wear-resistant cellulose coating and its preparation method relate to the field of surface treatment in mechanical engineering, including a single-phase cellulose coating and a multiphase cellulose composite coating. The wear-resistant cellulose coating is located on the surface of an inert substrate. The preparation method of the wear-resistant cellulose coating includes mixing cellulose or a mixture of cellulose and two-dimensional materials with an organic solvent, ultrasonic oscillation, and dropping the obtained cellulose liquid on the surface of the inert substrate, and standing until the solvent volatilizes completely to obtain the cellulose coating. The cellulose coating prepared by the present invention has excellent wear resistance. After the friction and wear test in the air, the friction coefficient reaches 0.052, and the wear rate is on the order of 10-9 mm3 / Nm. Therefore, the prepared wear-resistant cellulose coating can meet the wear resistance requirements of materials or components with high wear resistance requirements.

Description

Technical Field

[0001] This article relates to the surface treatment technology of mechanical engineering, especially a wear-resistant cellulose coating and its preparation method. Background Art

[0002] The wear-resistant cellulose coating is a coating technology used to enhance the wear resistance of the surface of mechanical components. In the fields of construction, mechanical manufacturing, etc., the wear-resistant cellulose coating is widely used to improve the service life of the surface of mechanical components. In the preparation of traditional cellulose coatings, chemical treatment methods are generally used (Sun XH, et al, Transparent and High Barrier Plasma Functionalized Acrylic Coated Cellulose Triacetate Films, Progress in Organic Coatings, 2021, 150, 105988); while in the preparation of wear-resistant cellulose coatings, the combination and treatment methods of the coatings need to be changed (Shi SC, et al, Surface Characterization and Tribological Behavior of Graphene-Reinforced Cellulose Composites Prepared by Large-Area Spray Coating on Flexible Substrate, Coatings 2020, 10, 1176). This can not only improve the friction and wear performance of the wear-resistant cellulose coating, but also ensure the environmental protection characteristics of the coating, and can be widely used in the fields of aircraft, automobiles, etc. Based on cellulose as the base material, combined with two-dimensional materials, and then researching and developing wear-resistant coatings has become one of the current hot research directions (Shi SC, et al, Aluminum and Alumina / MoS2 / Cellulose Derivative Composite: Design and Performance, Materials Research Express, 2022, 9, 114001). The wear-resistant cellulose coating can be used on the surfaces of various substrates, such as metals, ceramics, plastics, etc., to improve their surface wear resistance and thus extend their service life. Summary of the Invention

[0003] This application provides a wear-resistant cellulose coating and its preparation method. The wear-resistant cellulose coating prepared by this method endows inert substrates with excellent wear resistance and can meet the wear resistance requirements of materials or components with high wear resistance requirements.

[0004] The present application provides a wear-resistant cellulose coating. Among them, the wear-resistant cellulose coating includes: a single-phase cellulose coating and a multi-phase cellulose composite coating; the wear-resistant cellulose coating is located on the surface of an inert substrate.

[0005] In the cellulose coating provided by the present invention, the cellulose material is selected from one or more of cellulose and its derivatives; preferably, the cellulose material is hydroxypropyl methyl cellulose (HPMC).

[0006] In the cellulose coating provided by the present invention, the inert substrate is selected from one or more of steel-based plates, copper-based plates, aluminum-based plates, and ceramic-based plates; preferably, the inert substrate is a steel-based plate. The surface roughness of the steel-based plate is 0.1 - 0.5 μm.

[0007] In the cellulose coating provided by the present invention, the cellulose coating can be dropped on various substrates such as zirconia, sapphire glass, bearing steel, copper, aluminum, and inorganic substances. By introducing the wear-resistant cellulose coating, the service life of the inert substrate in the atmospheric environment is greatly improved.

[0008] On the other hand, the present invention provides a method for preparing the above-mentioned wear-resistant cellulose coating, which includes the following steps:

[0009] (1) Mix the cellulose material and the organic solvent evenly in a certain proportion, and then perform ultrasonic oscillation and static settlement; the concentration of the cellulose solution is 0.2 to 10 mg / mL;

[0010] (2) Mix the cellulose material, one or two two-dimensional materials, and the organic solvent evenly in a certain proportion, and then perform ultrasonic oscillation and static settlement to obtain a mixed solution; the total mass percentage of the two-dimensional material in the two-dimensional material and cellulose is 2.0% to 20.0%. When there are two two-dimensional materials, the mass ratio of the two two-dimensional materials is 1:1; the concentration of the mixture of the cellulose material and the two-dimensional material in the mixed solution is 0.2 to 10 mg / mL;

[0011] (3) Centrifuge the liquid obtained in step (1) after ultrasonic oscillation, take the supernatant and drop it on the surface of the inert substrate, and let it stand until the solvent evaporates completely to obtain a single-phase cellulose coating; or drop the liquid obtained in step (2) on the surface of the inert substrate, and let it stand until the solvent evaporates completely to obtain a multi-phase cellulose coating.

[0012] Optionally, the method for preparing the wear-resistant cellulose coating consists only of the above three steps.

[0013] In the method for preparing the wear-resistant cellulose coating provided by the present invention, the organic solvent is selected from one or more of toluene, isopropanol, absolute ethanol, and acetone; preferably, the organic solvent is isopropanol.

[0014] In the method for preparing the wear-resistant cellulose coating provided by the present invention, the two-dimensional material is selected from one or more of graphene, molybdenum disulfide (MoS2), tungsten disulfide (WS2), MXenes, and hexagonal boron nitride; preferably, the two-dimensional material is graphene and WS2.

[0015] In the method for preparing the wear-resistant cellulose coating provided by the present invention, the ultrasonic oscillation frequency in steps (1) and (2) is 20 kHz to 40 kHz, the oscillation power is 100 W to 200 W, the oscillation time is 45 min, the standing time is 2 - 4 hours, the centrifugation speed is 6000 rpm, and the centrifugation time is 30 minutes. In the method for preparing the wear-resistant cellulose coating provided by the present invention, the ultrasonic oscillation environment in steps (1) and (2) can be in the atmospheric environment or can be ultrasonic oscillation after sealing.

[0016] The wear-resistant cellulose coating prepared by the method of the present application endows the inert substrate with excellent wear resistance. After the friction and wear test in the air, the friction coefficient reaches 0.052, and the wear rate is 10 -9 mm 3 / Nm order of magnitude. Therefore, the prepared wear-resistant cellulose coating can meet the wear resistance requirements of materials or components with high wear resistance requirements.

[0017] Other features and advantages of the present application will be described in the subsequent specification, and part of them will become obvious from the specification or will be understood by implementing the present application. Other advantages of the present application can be realized and obtained through the solutions described in the specification, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings are used to provide an understanding of the technical solutions of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solutions of the present application and do not constitute a limitation to the technical solutions of the present application.

[0019] Figure 1 It is the tribological test curve of the low-concentration single-phase cellulose coating on the steel plate substrate in Example 1 of the present application.

[0020] Figure 2 It is the wear rate test curve of the low-concentration single-phase cellulose coating on the steel plate substrate in Example 1 of the present application.

[0021] Figure 3 It is the tribological test curve of the low-concentration multiphase cellulose coating on the steel plate substrate in Example 2 of the present application.

[0022] Figure 4 It is the wear rate test curve of the low-concentration multiphase cellulose coating on the steel plate substrate in Example 2 of the present application.

[0023] Figure 5 This is the tribological test curve of the high-concentration multiphase cellulose coating in Example 3 of this application on a steel substrate.

[0024] Figure 6 This is the wear rate test curve of the high-concentration multiphase cellulose coating in Example 3 of this application on a steel substrate. Detailed implementation manners

[0025] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined arbitrarily with each other.

[0026] In the specific implementation manners of the present invention, the wear-resistant cellulose coating includes: a single-phase cellulose coating and a multiphase cellulose composite coating; the wear-resistant cellulose coating is located on the surface of an inert substrate.

[0027] In the specific implementation manners of the present invention, the cellulose material is selected from one or more of cellulose and its derivatives; preferably, the cellulose material is hydroxypropyl methylcellulose (HPMC). Materials with structures similar to methylcellulose and HPMC can all achieve similar technical effects, and the friction coefficient is about 0.05.

[0028] In the specific implementation manners of the present invention, the inert substrate is selected from one or more of steel-based plates, copper-based plates, aluminum-based plates, and ceramic-based plates; preferably, the inert substrate is a steel-based plate. The surface roughness of the steel-based plate is 0.1 - 0.5 μm.

[0029] In the specific implementation manners of the present invention, the organic solvent is selected from one or more of toluene, isopropanol, absolute ethanol, and acetone; preferably, the organic solvent is isopropanol. The concentration of the cellulose solution is 0.2 to 10 mg / mL.

[0030] In the specific implementation manners of the present invention, the mass percentage of the two-dimensional material to cellulose is 2.0% to 20.0%, and the mass ratio between the two two-dimensional materials is 1:1; the concentration of the mixture of the cellulose material and the two-dimensional material in the organic solvent is 0.2 to 10 mg / mL.

[0031] In the specific implementation manners of the present invention, the two-dimensional material is selected from one or more of graphene, molybdenum disulfide (MoS2), tungsten disulfide (WS2), MXenes, and hexagonal boron nitride; preferably, the two-dimensional materials are graphene and WS2.

[0032] In the specific embodiment of the present invention, the frequency of the ultrasonic oscillation is 20 kHz to 40 kHz, the oscillation power is 100 W to 200 W, the oscillation time is 45 min, the standing time is 2 - 4 hours, the centrifugation speed is 6000 rpm, and the centrifugation time is 30 minutes.

[0033] In the specific embodiment of the present invention, the cellulose coating can be dropped on various substrates such as zirconia, sapphire glass, bearing steel, copper, aluminum, and inorganic substances. By introducing the wear-resistant cellulose coating, the service life of the inert substrate in the atmospheric environment is greatly improved. In the specific embodiment of the present invention, the wear-resistant cellulose coating endows the inert substrate with excellent wear resistance. After the friction and wear test in the air, the friction coefficient reaches 0.052, and the wear rate is 10 -9 mm 3 / Nm magnitude. Therefore, the prepared wear-resistant cellulose coating can meet the wear resistance requirements of materials or components with high wear resistance requirements.

[0034] Example 1

[0035] First, pour 100 mL of isopropanol into a glass beaker. Then, add 20 mg of HPMC powder (Shanghai Aladdin Biochemical Technology Co., Ltd.) into the glass beaker containing isopropanol. Subsequently, the glass beaker containing HPMC and isopropanol is sealed at room temperature and ultrasonically oscillated for 45 minutes (ultrasonic power is 150 W, frequency is 30 kHz). The solution after ultrasonic oscillation is further centrifuged (centrifugation speed is 6000 rpm, centrifugation time is 30 minutes). After obtaining the supernatant, it is left standing for 2 hours to obtain a uniform HPMC solution with a concentration of 0.2 mg / mL. Subsequently, the uniform cellulose coating solution is dropped onto the surface of a steel substrate with a surface roughness of 0.2 μm, and placed in a room temperature environment. After the isopropanol has completely evaporated, a single-phase cellulose coating is obtained. The tribological test curve of the single-phase cellulose coating in the air is as Figure 1 shown, and the wear rate test curve is as Figure 2 shown.

[0036] Example 2

[0037] First, pour 500 mL of isopropanol into a glass beaker. Subsequently, add 80 mg of HPMC powder (Shanghai Aladdin Biochemical Technology Co., Ltd.), 10 mg of graphene powder (Shanghai Aladdin Biochemical Technology Co., Ltd.), and 10 mg of WS2 powder (Shanghai Aladdin Biochemical Technology Co., Ltd.) into the glass beaker containing isopropanol. Then, seal the glass beaker containing HPMC, graphene, WS2, and isopropanol at room temperature and ultrasonically vibrate for 45 minutes (ultrasonic power is 150 W, frequency is 30 kHz). Further centrifuge the ultrasonically vibrated solution (centrifugation speed is 6000 rpm, centrifugation time is 30 minutes). After obtaining the supernatant, let it stand for 4 hours to obtain a uniform HPMC solution with a concentration of 10 mg / mL. Subsequently, drop the uniform cellulose coating solution onto the surface of a steel substrate with a surface roughness of 0.3 μm, and place it in a room temperature environment. Wait until the isopropanol has completely evaporated to obtain a multiphase cellulose coating. The tribological test curve of the multiphase cellulose coating in air is as Figure 3 shown, and the wear rate test curve is as Figure 4 shown.

[0038] Example 3

[0039] First, pour 200 mL of isopropanol into a glass beaker. Subsequently, add 1980 mg of HPMC powder (Shanghai Aladdin Biochemical Technology Co., Ltd.), 10 mg of graphene powder (Shanghai Aladdin Biochemical Technology Co., Ltd.), and 10 mg of WS2 powder (Shanghai Aladdin Biochemical Technology Co., Ltd.) into the glass beaker containing isopropanol. Then, seal the glass beaker containing HPMC, graphene, WS2, and isopropanol at room temperature and ultrasonically vibrate for 45 minutes (ultrasonic power is 150 W, frequency is 30 kHz). Further centrifuge the ultrasonically vibrated solution (centrifugation speed is 6000 rpm, centrifugation time is 30 minutes). After obtaining the supernatant, let it stand for 3 hours to obtain a uniform HPMC solution with a concentration of 10 mg / mL. Subsequently, drop the uniform cellulose coating solution onto the surface of a steel substrate with a surface roughness of 0.3 μm, and place it in a room temperature environment. Wait until the isopropanol has completely evaporated to obtain a multiphase cellulose coating. The tribological test curve of the multiphase cellulose coating in air is as Figure 3 shown, and the wear rate test curve is as Figure 4 shown.

[0040] Example 4

[0041] First, pour 100 mL of isopropanol into a glass beaker. Subsequently, add 20 mg of cellulose powder (Shanghai Aladdin Biochemical Technology Co., Ltd.) to the glass beaker containing isopropanol. Then, seal the glass beaker containing cellulose powder and isopropanol at room temperature and ultrasonically vibrate for 45 minutes (ultrasonic power is 150 W, frequency is 30 kHz). Centrifuge the solution after ultrasonic vibration (centrifugation speed is 6000 rpm, centrifugation time is 30 minutes). After obtaining the supernatant, let it stand for 2 hours to obtain a uniform cellulose powder solution with a concentration of 0.2 mg / mL. Subsequently, drop the uniform cellulose coating solution onto the surface of a silicon substrate with a surface roughness of 0.5 nm, place it in a room temperature environment, and wait for the isopropanol to evaporate completely to obtain a single-phase cellulose coating. The coefficient of friction is 0.064, and the wear rate is 10 -8 mm 3 in the order of / Nm.

[0042] Example 5

[0043] First, pour 300 mL of isopropanol into a glass beaker. Subsequently, add 80 mg of cellulose powder (Shanghai Aladdin Biochemical Technology Co., Ltd.) and 10 mg of WS2 powder (Shanghai Aladdin Biochemical Technology Co., Ltd.) to the glass beaker containing isopropanol. Then, seal the glass beaker containing cellulose powder, WS2 and isopropanol at room temperature and ultrasonically vibrate for 45 minutes (ultrasonic power is 150 W, frequency is 30 kHz). Centrifuge the solution after ultrasonic vibration (centrifugation speed is 6000 rpm, centrifugation time is 30 minutes). After obtaining the supernatant, let it stand for 3 hours to obtain a uniform cellulose powder solution with a concentration of 0.3 mg / mL. Subsequently, drop the uniform cellulose coating solution onto the surface of a silicon substrate with a surface roughness of 0.5 nm, place it in a room temperature environment, and wait for the isopropanol to evaporate completely to obtain a multi-phase cellulose coating. The coefficient of friction is 0.058, and the wear rate is 10 - 8 mm 3 in the order of / Nm.

[0044] Example 6

[0045] First, pour 10 mL of isopropanol into a glass beaker. Subsequently, add 10 mg of methylcellulose powder (Shanghai Aladdin Biochemical Technology Co., Ltd.) into the glass beaker containing isopropanol. Then, seal the glass beaker containing methylcellulose and isopropanol at room temperature and ultrasonically vibrate it for 45 minutes (ultrasonic power is 150 W, frequency is 30 kHz). Centrifuge the ultrasonically vibrated solution further (centrifugation speed is 6000 rpm, centrifugation time is 30 minutes). After obtaining the supernatant, let it stand for 2 hours to obtain a uniform HPMC solution with a concentration of 1 mg / mL. Subsequently, drop the uniform cellulose coating solution onto the surface of a steel substrate with a surface roughness of 0.2 μm, place it in a room temperature environment, and wait for the isopropanol to completely volatilize to obtain a multiphase cellulose coating. The friction coefficient is 0.070, and the wear rate is 10 -7 mm 3 in the order of / Nm.

[0046] Comparative Example 1

[0047] Conduct a tribological performance test in air on a steel substrate without surface coating dripping using the present invention. The experimental results show that the friction coefficient of the steel substrate in air is 0.3, and the wear rate is 10 -4 mm 3 in the order of / Nm.

[0048] Comparative Example 2

[0049] Conduct a tribological performance test in air on a silicon substrate without surface coating dripping using the present invention. The experimental results show that the friction coefficient of the silicon substrate in air is 0.78, and the wear rate is 10 -3 mm 3 in the order of / Nm.

[0050] Comparative Example 3

[0051] Prepare a two-dimensional material coating using a similar solution preparation method. The preparation method is as follows: Add 20 mL of isopropanol into a glass beaker, then weigh 100 mg of graphene powder with an electronic balance and add it into the glass beaker. After sealing, ultrasonically vibrate it at room temperature for 45 minutes (ultrasonic power is 150 W, frequency is 30 kHz) to make it uniformly dispersed. Centrifuge the ultrasonically vibrated solution further (centrifugation speed is 6000 rpm, centrifugation time is 30 minutes). After obtaining the supernatant, use a burette to suck this solution and drop it on the steel substrate. After the solvent volatilizes, conduct a friction and wear experiment. After the experiment, the friction coefficient is 0.25, and the wear rate is 10 -5 mm 3 in the order of / Nm.

[0052] Performance Test

[0053] The cellulose coating prepared in Example 1 was subjected to friction and wear testing. The instrument used was a reciprocating ball-on-disk tribometer (CETR, Inc., USA, UMT-5). The friction pair parameters were as follows: the load was 4 N, the frequency was 2 Hz, the test temperature was room temperature, and the humidity was 10%.

[0054] Figure 1 The curve in... is based on the steel substrate bottom surface. The test results show that in air, for the steel substrate with a cellulose coating applied by surface dripping, the friction coefficient can reach 0.055.

[0055] Figure 2 The curve in... is based on the steel substrate surface. The test results show that in air, for the steel substrate with a cellulose coating applied by surface dripping, the wear rate can reach 10 -9 mm 3 / Nm order of magnitude.

[0056] Examples 2 and 3 were subjected to friction and wear testing according to the test method of Example 1. The test results are shown in detail in Figure 3 、 Figure 4 、 Figure 5 and Figure 6 .

[0057] Although the disclosed embodiments of the present application are as above, the described content is only an embodiment for facilitating the understanding of the present application and is not intended to limit the present application. Any person skilled in the art within the scope of the present application can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed by the present application. However, the protection scope of the present application shall still be subject to the scope defined by the appended claims.

Claims

1. Use of an abrasion-resistant cellulose coating in enhancing the abrasion resistance of an inert substrate, characterized in that, The composition of the wear-resistant cellulose coating is: a single-phase cellulose coating or a multi-phase cellulose composite coating; the wear-resistant cellulose coating is located on the surface of an inert substrate; The cellulose is hydroxypropyl methyl cellulose (HPMC); the inert substrate is a steel-based sheet; the surface roughness of the steel-based sheet is 0.5 nm - 0.3 μm; The preparation method of the wear-resistant cellulose coating includes the following steps: (1) Mix the cellulose material with an organic solvent evenly to obtain a cellulose solution, and perform ultrasonic oscillation and standing; the concentration of the cellulose solution is 0.2 to 10 mg / mL; (2) Mix the cellulose material, one or two two-dimensional materials, and an organic solvent evenly according to a certain ratio, and perform ultrasonic oscillation and standing to obtain a mixed solution; the percentage of the two-dimensional material in the total mass of the two-dimensional material and cellulose is 2.0% to 20.0%. When there are two two-dimensional materials, the mass ratio of the two two-dimensional materials is 1:1; the concentration of the mixture of the cellulose material and the two-dimensional material in the mixed solution is 0.2 to 10 mg / mL; (3) Centrifuge the liquid obtained in step (1) after ultrasonic oscillation, take the supernatant, and drop it on the surface of an inert substrate, then let it stand until the solvent has completely evaporated to obtain a single-phase cellulose coating; or take 1 mL of the liquid obtained in step (2) and drop it on the surface of a 2×2 cm 2 inert substrate, let it stand until the solvent has completely evaporated to obtain a multi-phase cellulose coating.

2. The use according to claim 1, wherein, The organic solvent is selected from one or more of toluene, isopropanol, absolute ethanol, and acetone.

3. The use according to claim 1, wherein, The two-dimensional material is selected from one or more of graphene, molybdenum disulfide (MoS2), tungsten disulfide (WS2), MXenes, and hexagonal boron nitride.

4. The use according to claim 1, wherein The frequency of the ultrasonic oscillation in steps (1) and (2) is 20 kHz to 40 kHz, the oscillation power is 100 W to 200 W, and the oscillation time is 45 min; the standing time is 2 - 4 hours, the centrifugation speed is 6000 rpm, and the centrifugation time is 30 minutes.

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