MXene-based coating with near-infrared light induction interaction effect and preparation method of MXene-based coating

Abstract

The invention discloses an MXene-based coating with a near-infrared light induction interaction effect and a preparation method of the MXene-based coating, and relates to the technical field of coatings. The preparation method comprises the following steps: a nano microcapsule and MXene powder are subjected to in-situ growth to form a composite dispersion liquid, the nano microcapsule is of a core-shell structure, a shell layer material is selected from at least one of polyaniline, polyurea, polyurethane, polyacrylate and silicon dioxide, a core contains a functional substance, and the surface of the core contains a porous material. The functional substances are selected from at least two of a corrosion inhibitor, a fluorescent indicator and a lubricant; adding a thermal reversible coating containing dynamic covalent bonds and a curing agent into the composite dispersion liquid, and uniformly mixing to form a homogeneous coating; and spraying the homogeneous coating on the surface of a base material, and curing to obtain the coating. The coating is high in mechanical strength, has a near-infrared light triggered self-repairing function, is high in self-repairing rate, and can realize multiple functions such as fluorescence labeling, corrosion early warning and lubrication coordinated regulation and control.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and particularly to an MXene-based coating with near-infrared light-induced interaction effect and a preparation method thereof. Background Art

[0002] With the development of industry, coating technology has been increasingly widely used in the field of protection, but it also faces challenges such as single function and insufficient environmental friendliness. Traditional coatings mainly rely on physical barriers and are difficult to meet the requirements for diverse performances under complex working conditions.

[0003] In recent years, although thermoreversible coatings have self-healing ability, their mechanical strength and functionality are insufficient. As an emerging two-dimensional material, MXene provides new possibilities for coating protection with its multi-dimensional structure, rich functional groups, and excellent photothermal conversion performance. Among them, the composition of MXene can be expressed as Mn+1XnTx, where M represents transition metals, usually titanium Ti, vanadium V, chromium Cr, and molybdenum Mo, etc., X is usually carbon C or nitrogen N, and Tx represents the terminal groups on the material surface, such as hydroxyl (-OH), oxygen (-O), fluorine (-F), or chlorine (-Cl).

[0004] Therefore, how to improve the mechanical strength and intelligent self-healing function of coatings, and endow coatings with diverse performances to meet the requirements for coating performances under complex working conditions is the current development direction of coating technology. Based on this, the present invention provides an MXene-based coating with near-infrared light-induced interaction effect and a preparation method thereof. Summary of the Invention

[0005] The present invention aims to solve the technical problems that the existing coatings have poor mechanical strength and self-healing ability, and the coating functions are single, and aims to provide an MXene-based coating with near-infrared light-induced interaction effect and a preparation method thereof. By organically combining functionalized nanocapsules, MXene materials, and a dynamic thermoreversible system, the obtained coating has high mechanical strength, has a near-infrared light-triggered self-healing function, and has a high self-healing rate. At the same time, it combines multiple functions such as fluorescence labeling, corrosion warning, and lubrication synergistic regulation, and solves the problems of single function and poor environmental responsiveness of traditional protective coatings.

[0006] The present invention is realized by the following technical solutions:

[0007] The present invention provides a preparation method of an MXene-based coating with near-infrared light-induced interaction effect, comprising the following steps:

[0008] (1) The nano microcapsules and MXene powder are formed into a composite powder through in-situ growth. The nano microcapsules have a mesoporous structure. Among them, the nano microcapsule material is selected from at least one of polyurea, polyurethane, polyacrylate, and silica. A functional substance is electrostatically adsorbed in the mesopores, and the functional substance is selected from at least two of corrosion inhibitors, fluorescent indicators, and lubricants;

[0009] (2) Add a thermoreversible coating containing dynamic covalent bonds and a curing agent to the composite powder, mix evenly to form a homogeneous coating;

[0010] (3) Spray the homogeneous coating on the surface of the substrate by a spraying process, and form an MXene-based coating with a near-infrared light-induced interaction effect after curing.

[0011] Further, the nano microcapsules are selected as mesoporous silica microcapsules.

[0012] Further, the preparation method of the MXene powder is as follows:

[0013] Slowly add the MAX precursor to the hydrofluoric acid etching solution, stir at 18 °C to 30 °C for 1 h to 24 h, centrifuge the reaction solution, then wash with deionized water, and obtain MXene powder after drying.

[0014] Further, the MAX precursor is at least one of two-dimensional materials such as Ti3AlC2, Ti2AlC, Ti4AlN3, and Cr2AlC.

[0015] Further, the mass ratio of the nano microcapsules to the MXene powder is 1:(1 - 100).

[0016] Further, the in-situ growth technology is the sol-gel method or the in-situ polymerization method, the reaction temperature is 40 - 80 °C, and the reaction time is 6 - 24 h.

[0017] Further, the dynamic covalent bond is selected from at least one of Diels-Alder bonds, disulfide bonds, diselenide bonds, Schiff base bonds, oxime-carbamate bonds, hydrazone bonds, and phenol-carbamate bonds.

[0018] Further, the thermoreversible coating containing dynamic covalent bonds is a Diels-Alder bond type thermoreversible waterborne polyurethane.

[0019] Further, the mass ratio of the nano microcapsules to the thermoreversible coating containing dynamic covalent bonds and the curing agent is 1:(1 - 100):(1 - 100).

[0020] The second object of the present invention is to provide an MXene-based coating with a near-infrared light-induced interaction effect, which is prepared by the aforementioned method.

[0021] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0022] 1. When the coating of the present invention is damaged, the warning agent can emit fluorescence warning. At this time, irradiating the damaged area with near-infrared light can trigger the self-healing function, and further release the internal lubricant and corrosion inhibitor to enhance the coating performance.

[0023] 2. By in-situ compounding functionalized nano-microcapsules with MXene materials and introducing a dynamic thermoreversible system, under near-infrared light irradiation, MXene generates a local high-temperature thermal effect, raising the coating temperature to break the dynamic covalent bonds. After cooling, the dynamic covalent bonds are reorganized to repair the microcracks of the coating, realizing self-healing. At the same time, the mesopores of the nano-microcapsules rupture, releasing the functional substances in the mesopores. The released lubricant can reduce the friction coefficient of the coating, and the corrosion inhibitor can achieve the corrosion inhibition effect. Therefore, by organically combining the functionalized nano-microcapsules, MXene materials, and the dynamic thermoreversible system, the present invention realizes multiple functions such as enhancing the mechanical strength of the coating, near-infrared light-triggered self-healing, fluorescence labeling, corrosion warning, and lubrication synergistic regulation, and solves the problems of single function and poor environmental responsiveness of traditional protective coatings. Specific Embodiments

[0024] To make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the illustrative embodiments and their descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0025] The following details the embodiments of an MXene-based coating with a near-infrared light sensing interaction effect and its preparation method of the present invention. However, there may be cases where unnecessary details are omitted. For example, there are cases where the detailed descriptions of well-known matters and repeated descriptions are omitted. This is to avoid the following descriptions from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art.

[0026] The "range" disclosed in this application is defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a specific range. The range defined in this way can include the end values or not include the end values, and can be combined arbitrarily, that is, any lower limit can be combined with any upper limit to form a range.

[0027] If there is no special description, all the embodiments and optional embodiments of this application can be combined with each other to form a new technical solution.

[0028] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form new technical solutions.

[0029] Unless otherwise specified, the terms "comprising" and "including" mentioned in this application mean open-ended, and can also be closed-ended. For example, the terms "comprising" and "including" can mean that other substances not listed can also be included or contained, or can only include or contain the substances listed.

[0030] Unless otherwise specified, all steps of this application can be carried out sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method can include steps (a) and (b) carried out sequentially, or can also include steps (b) and (a) carried out sequentially. For example, it is mentioned that the method may further include step (c), which means that step (c) can be added to the method in any order. For example, the method can include steps (a), (b) and (c), or can also include steps (a), (c) and (b), or can also include steps (c), (a) and (b), etc.

[0031] The present invention provides a method for preparing an MXene-based coating with a near-infrared light-induced interaction effect, comprising the following steps:

[0032] (1) Forming a composite powder by in-situ growth of nano-microcapsules and MXene powder. The nano-microcapsules have a mesoporous structure. Among them, the nano-microcapsule material is selected from at least one of polyurea, polyurethane, polyacrylate, and silica. Functional substances are electrostatically adsorbed in the mesopores, and the functional substances are selected from at least two of corrosion inhibitors, fluorescent indicators, and lubricants;

[0033] (2) Adding a thermoreversible coating containing dynamic covalent bonds and a curing agent to the composite powder, and mixing evenly to form a homogeneous coating;

[0034] (3) Spraying the homogeneous coating on the surface of the substrate by a spraying process, and forming an MXene-based coating with a near-infrared light-induced interaction effect after curing; wherein, the spraying process adopts any one of air spraying, airless spraying, electrostatic spraying, roll coating spraying, thermal spraying, ultrasonic spraying, and thin film deposition spraying, and the surface of the substrate refers to the surface of metal, plastic or fabric.

[0035] In the present invention, MXene will generate local high temperature under near-infrared light irradiation. The thermoreversible coating containing dynamic covalent bonds will undergo a thermoreversible reaction when heated. Specifically, the chemical bonds break when heated, and the reaction proceeds in the reverse direction. When cooled, the chemical bonds re-form, and the reaction proceeds in the forward direction. After cooling and recombination, microcracks can be repaired. The mechanical strength of the nano-microcapsule shell layer is relatively low, and it can rupture and decompose under high temperature stimulation, releasing functional substances such as corrosion inhibitors, fluorescent agents, and lubricants inside.

[0036] In the present invention, the surface of the MXene material is rich in functional groups such as hydroxyl (-OH), oxygen (-O), fluorine (-F), or chlorine (-Cl), which can form hydrogen bonds, covalent bonds, or ionic bonds with a thermoreversible coating containing dynamic covalent bonds, enhancing the interfacial binding force and improving the mechanical strength of the coating.

[0037] Therefore, in the present invention, by in-situ compounding functionalized nanocapsules with the MXene material and introducing a dynamic thermoreversible system, under the irradiation of near-infrared light with a wavelength of 750 nm to 2500 nm, the MXene generates a local high-temperature thermal effect, raising the coating temperature to break the dynamic covalent bonds. After cooling, the dynamic covalent bonds are reorganized to repair the microcracks in the coating. Meanwhile, the mesopores of the nanocapsules rupture, releasing the functional substances inside the mesopores. The released lubricant can reduce the friction coefficient of the coating, the corrosion inhibitor can achieve the corrosion inhibition effect, and the warning agent can achieve the warning effect. Therefore, by organically combining the functionalized nanocapsules, the MXene material, and the dynamic thermoreversible system, the present invention realizes multiple functions such as the improvement of the mechanical strength of the coating, near-infrared light-triggered self-repair, fluorescence labeling, corrosion warning, and lubrication synergistic regulation, solving the problems of single function and poor environmental responsiveness of traditional protective coatings.

[0038] Furthermore, the nanocapsules are selected as mesoporous silica microcapsules. The mechanical strength of the shell layer of the mesoporous silica microcapsules is relatively low, facilitating rupture under external stimuli such as high temperature to release the internal corrosion inhibitor, fluorescent agent, and lubricant. Among them, the corrosion inhibitor is selected as benzotriazole to achieve the corrosion inhibition effect, the fluorescent agent is selected as rhodamine B to achieve the warning effect, the lubricant is selected as tung oil to achieve the lubrication effect. The released benzotriazole inhibits metal corrosion, the fluorescence intensity of rhodamine B is linearly related to the corrosion depth, tung oil can reduce the friction coefficient, and the corrosion inhibitor, lubricant, fluorescent agent, and polyaniline shell layer can degrade in the natural environment.

[0039] Furthermore, the preparation method of the MXene powder is as follows:

[0040] The MAX precursor is slowly added to the hydrofluoric acid etching solution, stirred at 18 °C to 30 °C for 1 h to 24 h, the reaction solution is centrifuged, and then washed with deionized water and dried to obtain the Mxene powder.

[0041] Furthermore, the MAX precursor is at least one of two-dimensional materials such as Ti3AlC2, Ti2AlC, Ti4AlN3, Cr2AlC. Preferably, the MAX precursor is selected as Ti3AlC2.

[0042] Furthermore, the mass ratio of the nanocapsules to the MXene powder is 1:(1 - 100), preferably 1:(1 - 50), more preferably 1:(1 - 20).

[0043] Furthermore, the in-situ growth technique is the sol-gel method or the in-situ polymerization method, with a reaction temperature of 40-80 °C and a reaction time of 6-24 h. Preferably, the in-situ polymerization method is adopted, which has the advantages of simplicity, high efficiency, and strong controllability, and can effectively realize the in-situ composite of nano microcapsules and MXene materials.

[0044] Furthermore, the dynamic covalent bond-containing group is selected from at least one of Diels-Alder bonds, disulfide bonds, diselenide bonds, Schiff base bonds, oxime-carbamate bonds, acylhydrazone bonds, and phenol-carbamate bonds. Preferably, it is a Diels-Alder bond.

[0045] More preferably, the thermoreversible coating containing dynamic covalent bonds is a Diels-Alder bond-type thermoreversible waterborne polyurethane. In the following examples, the Diels-Alder bond-type thermoreversible waterborne polyurethane is used as the experimental object.

[0046] Furthermore, the mass ratio of the nano microcapsules, the thermoreversible coating containing dynamic covalent bonds, and the curing agent is 1:(1-100):(1-100). Preferably, it is 1:(1-50):(1-50), and more preferably, it is 1:(1-20):(1-20).

[0047] The second object of the present invention is to provide an MXene-based coating with a near-infrared light-induced interaction effect, which is prepared by the aforementioned method. The MXene-based coating with a near-infrared light-induced interaction effect prepared by the present invention is mainly applied to the surface of equipment for oil and gas wells. Specifically, the coating of the present invention is used on the surface of equipment for oil and gas wells with poor visibility. When the coating is damaged, it can emit a fluorescence warning, and at this time, irradiating the damaged area with near-infrared light can trigger the self-healing function.

[0048] The technical solutions of the present invention will be further described in detail below in conjunction with examples.

[0049] It should be noted that the experimental methods used in the examples are all conventional methods unless otherwise specified. The materials, reagents, methods, and instruments used are all conventional materials, reagents, methods, and instruments in this field, and those skilled in the art can obtain them through commercial channels without special instructions.

[0050] Example 1

[0051] In this example, mesoporous silica microcapsules are used, and the mesopores contain lubricating tung oil, corrosion inhibitor benzotriazole, and fluorescent agent rhodamine B at the same time.

[0052] A preparation method of an MXene-based coating with a near-infrared light-induced interaction effect includes the following steps:

[0053] (1) Slowly dissolve lithium fluoride powder in 9 mol / L hydrochloric acid solution, stir until lithium fluoride is fully dissolved to obtain a hydrofluoric acid etching solution. Slowly add Ti3AlC2 to the hydrofluoric acid etching solution (the mass ratio of lithium fluoride to Ti3AlC2 is 1:1), and mechanically stir at 20 °C for 24 h. Transfer the reacted solution to a centrifuge tube for centrifugation, and then wash with deionized water to obtain Mxene precipitate. After drying, Mxene powder is obtained.

[0054] (2) Ultrasonically disperse 100 parts of mesoporous silica microcapsules in deionized water. After stirring for 30 min, add 100 parts of Mxene powder, 50 parts of tung oil, 50 parts of corrosion inhibitor benzotriazole, and 50 parts of rhodamine B. Wash the reacted product with deionized water to obtain a composite precipitate. After drying, composite powder is obtained.

[0055] (3) Dissolve the obtained composite powder in deionized water, then add 100 parts of thermoreversible waterborne polyurethane containing Diels - Alder bonds and 100 parts of aromatic amine curing agent. After ultrasonic treatment for 5 minutes, stir at a high speed of 3000 rpm for 30 min to form a homogeneous coating.

[0056] (4) Coat the coating on the surface of Q345 steel by air pressure spraying. After curing at 80 °C for 24 h, a multifunctional MXene - based coating with a thickness of 20 μm and near - infrared light - induced interaction effect is formed.

[0057] Example 2

[0058] In this example, mesoporous silica microcapsules are used, and the mesopores contain lubricant tung oil and fluorescent agent rhodamine B.

[0059] A preparation method of a MXene - based coating with near - infrared light - induced interaction effect, comprising the following steps:

[0060] (1) Slowly dissolve lithium fluoride powder in 9 mol / L hydrochloric acid solution, stir until lithium fluoride is fully dissolved to obtain a hydrofluoric acid etching solution. Slowly add Ti3AlC2 to the hydrofluoric acid etching solution (the mass ratio of lithium fluoride to Ti3AlC2 is 1:1), and mechanically stir at 20 °C for 24 h. Transfer the reacted solution to a centrifuge tube for centrifugation, and then wash with deionized water to obtain Mxene precipitate. After drying, Mxene powder is obtained.

[0061] (2) Ultrasonically disperse 100 parts of mesoporous silica microcapsules in deionized water. After stirring for 30 min, add 100 parts of Mxene powder, 50 parts of tung oil and 50 parts of rhodamine B. Wash the reacted product with deionized water to obtain a composite precipitate. After drying, composite powder is obtained.

[0062] (3) Dissolve the obtained composite powder in deionized water, then add 100 parts of thermoreversible waterborne polyurethane containing Diels-Alder bonds and 100 parts of aromatic amine curing agent. After ultrasonic treatment for 5 minutes, stir at a high speed of 3000 rpm for 30 minutes to form a homogeneous coating.

[0063] (4) Coat the coating on the surface of Q345 steel by air spraying. After curing at 80 °C for 24 h, a multifunctional MXene-based coating with a thickness of 20 μm and near-infrared light-induced interaction effect is formed.

[0064] Example 3

[0065] In this example, mesoporous silica microcapsules are used, and the mesopores contain the lubricant corrosion inhibitor benzotriazole and the fluorescent agent rhodamine B.

[0066] A preparation method of a multifunctional MXene-based coating with near-infrared light-induced interaction effect includes the following steps:

[0067] (1) Slowly dissolve lithium fluoride powder in a 9 mol / L hydrochloric acid solution, stir until lithium fluoride is fully dissolved to obtain a hydrofluoric acid etching solution. Slowly add Ti3AlC2 to the hydrofluoric acid etching solution (the mass ratio of lithium fluoride to Ti3AlC2 is 1:1), and mechanically stir at 20 °C for 24 h. Transfer the reacted solution to a centrifuge tube for centrifugation, and then wash with deionized water to obtain Mxene precipitate. After drying, Mxene powder is obtained.

[0068] (2) Ultrasonically disperse 100 parts of mesoporous silica microcapsules in deionized water. After stirring for 30 minutes, add 100 parts of Mxene powder, 50 parts of corrosion inhibitor benzotriazole and 50 parts of rhodamine B. Wash the reacted product with deionized water to obtain a composite precipitate. After drying, composite powder is obtained.

[0069] (3) Dissolve the obtained composite powder in deionized water, then add 100 parts of thermoreversible waterborne polyurethane containing Diels-Alder bonds and 100 parts of aromatic amine curing agent. After ultrasonic treatment for 5 minutes, stir at a high speed of 3000 rpm for 30 minutes to form a homogeneous coating.

[0070] (4) Coat the coating on the surface of Q345 steel by air spraying. After curing at 80 °C for 24 h, a multifunctional MXene-based coating with a thickness of 20 μm and near-infrared light-induced interaction effect is formed.

[0071] Comparative Example 1

[0072] The difference between this comparative example and Example 1 is that no Mxene powder is added.

[0073] A preparation method of a Diels-Alder bond type mesoporous silica microcapsule coating, comprising the following steps:

[0074] (1) Ultrasonically disperse 100 parts of mesoporous silica microcapsules into deionized water. After stirring for 30 min, add 50 parts of lubricant tung oil, 50 parts of corrosion inhibitor benzotriazole, and 50 parts of rhodamine B. Wash the reaction product with deionized water to obtain a composite precipitate, and dry it to obtain a composite powder.

[0075] (2) Dissolve 50 parts of the composite powder into deionized water, then add 100 parts of thermoreversible waterborne polyurethane containing Diels-Alder bonds and 100 parts of aromatic amine curing agent. After ultrasonic treatment for 5 minutes, stir at a high speed of 3000 rpm for 30 min to form a homogeneous coating.

[0076] (3) Coat the coating on the surface of Q345 steel by air pressure spraying. After curing at 80 °C for 24 h, a Diels-Alder bond type mesoporous silica microcapsule coating with a thickness of 20 μm is formed.

[0077] Comparative Example 2

[0078] The difference between this comparative example and Example 1 is that no mesoporous silica microcapsules and functional substances in the mesopores are added.

[0079] A preparation method of an MXene-based coating with near-infrared light-induced interaction effect, comprising the following steps:

[0080] (1) Slowly dissolve lithium fluoride powder in a 9 mol / L hydrochloric acid solution, stir until lithium fluoride is fully dissolved to obtain a hydrofluoric acid etching solution. Slowly add Ti3AlC2 to the hydrofluoric acid etching solution (the mass ratio of lithium fluoride to Ti3AlC2 is 1:1), and mechanically stir at 20 °C for 24 h. Transfer the reaction solution to a centrifuge tube for centrifugation, and then wash it with deionized water to obtain an Mxene precipitate. Dry it to obtain Mxene powder.

[0081] (2) Ultrasonically disperse 100 parts of Mxene powder into deionized water, then add 100 parts of thermoreversible waterborne polyurethane containing Diels-Alder bonds and 100 parts of aromatic amine curing agent. After ultrasonic treatment for 5 minutes, stir at a high speed of 3000 rpm for 30 min to form a homogeneous coating.

[0082] (3) Coat the coating on the surface of Q345 steel by air pressure spraying. After curing at 80 °C for 24 h, a multifunctional MXene-based coating with a near-infrared light-induced interaction effect and a thickness of 20 μm is formed.

[0083] Comparative Example 3

[0084] The difference between this comparative example and Example 1 lies in that: no mesoporous silica microcapsules, internal functional substances, and MXene powder are added, and the coating is only formed by a thermoreversible waterborne polyurethane containing Diels-Alder bonds and a curing agent.

[0085] Related performance tests

[0086] 1. Functional performance test: Coat the coatings prepared in the examples and comparative examples on the surface of Q345 steel with a specification of 30×30×3 mm, and cure them at room temperature to form a shape. Use a scalpel to make a 10×10 mm scratch on the surface of the coating, and then place it in a 3.5 wt% NaCl solution. Electrochemical tests and fluorescence intensity detections are carried out at 30 min and 24 h respectively. The specific data are shown in Table 1 below.

[0087] Table 1. Data of electrochemical tests and fluorescence intensity detections

[0088]

[0089]

[0090] It can be seen from the data in Table 1 that the impedance modulus and fluorescence intensity of the coating prepared in this example are larger, while the impedance modulus and fluorescence intensity of the coating prepared in the comparative example are smaller, indicating that the coating prepared by the present invention has better corrosion resistance and fluorescence stability.

[0091] 2. Near-infrared light self-healing test: Coat the coatings prepared in the above examples and comparative examples on the surface of Q345 steel with a specification of 30×30×3 mm, and cure them at room temperature to form a shape. Place the coating on a sliding friction machine for a reciprocating friction experiment of 8 N, 2 Hz, 6 mm, and 1 h. After the experiment, measure the final stable friction coefficient and wear scar width. After the measurement, irradiate with 880 nm near-infrared light for 10 min, and measure the wear scar width again to calculate the self-healing rate. The specific data are shown in Table 2 below.

[0092] Table 2. Self-healing rate data

[0093]

[0094]

[0095] As can be seen from the data in Table 2, the coatings prepared in the embodiments of the present invention have strong self-healing ability. Especially in Embodiment 1, by combining functionalized nano-microcapsules, MXene materials, and a dynamic thermoreversible system, and when the mesoporous silica microcapsules contain both lubricants and corrosion inhibitors, the self-healing rate reaches over 66%. In Embodiments 2 and 3, the lack of some functional substances has a certain impact on the self-healing effect, resulting in a certain degree of decrease in the self-healing rate. In Comparative Example 1 and Comparative Example 3, due to the lack of MXene materials, the photothermal conversion effect cannot be achieved, resulting in the loss of the self-healing effect of the coating. In Comparative Example 2, the lack of mesoporous silica microcapsules and the functional substances inside them cannot cooperate with MXene, resulting in a decrease in the self-healing rate. Thus, it is proved that combining functionalized nano-microcapsules, MXene materials with a dynamic thermoreversible system, and the synergy of the three can effectively improve the self-healing effect of the coating.

[0096] 3. Mechanical strength test: The coatings prepared in the embodiments and comparative examples were subjected to a pull-out test, and the mechanical strength of the coatings was tested under 10% strain conditions. The specific data are shown in Table 3 below.

[0097] Table 3. Mechanical strength data

[0098]

[0099]

[0100] As can be seen from the data in Table 3, by combining functionalized nano-microcapsules, MXene materials with a dynamic thermoreversible system, and the synergy of the three, the present invention can improve the mechanical strength of the coating.

[0101] Finally, it should be noted that: The above specific embodiments are only used to elaborate in detail the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above description is only the specific implementation manners of the present invention and is not used to limit the protection scope of the present invention; Although the present invention has been described in detail with reference to the above specific embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the above embodiments, or perform equivalent replacements or improvements on some or all of the technical features; And these modifications, equivalent replacements, and improvements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and the description of the present invention.

Claims

1. A method for preparing a MXene-based coating with near-infrared light-induced interactive effect, characterized in that: The following steps are involved: (1) forming a composite powder by in-situ growth of nanocapsules and MXene powder, wherein the nanocapsules are of a mesoporous structure, wherein the nanocapsule material is selected from at least one of polyurea, polyurethane, polyacrylate, and silica, and functional substances are electrostatically adsorbed in the mesopores, wherein the functional substances are selected from at least two of a corrosion inhibitor, a fluorescent indicator, and a lubricant; (2) adding a thermally reversible coating containing dynamic covalent bonds and a curing agent to the composite powder, mixing them evenly to form a homogeneous coating; (3) A homogeneous coating is sprayed onto the surface of the substrate using a spraying process, and after curing, a MXene-based coating with a near-infrared light-sensitive interactive effect is formed.

2. The method for preparing a MXene-based coating with near-infrared light-induced interactive effect according to claim 1, characterized in that: The nanometer microcapsules are mesoporous silica microcapsules.

3. The method for preparing a MXene-based coating with near-infrared light-induced interactive effect according to claim 1, characterized in that: The preparation method of the MXene powder is: Slowly add the MAX precursor into the hydrofluoric acid etching solution, stir at 18°C ​​to 30°C for 1h to 24h, centrifuge the solution after the reaction, wash with deionized water, and dry to obtain MXene powder.

4. The method for preparing a MXene-based coating with near-infrared light-induced interactive effect according to claim 3, characterized in that: The MAX precursor is at least one of Ti3AlC2, Ti2AlC, Ti4AlN3, and Cr2AlC two-dimensional materials.

5. The method for preparing a MXene-based coating with near-infrared light-induced interactive effect according to claim 1, characterized in that: The mass ratio of the nano-microcapsules to the MXene powder is 1:(1-100).

6. The method for preparing a MXene-based coating with near-infrared light-induced interactive effect according to claim 1, characterized in that: The in-situ growth technology is a sol-gel method or an in-situ polymerization method, with a reaction temperature of 40 to 80° C. and a reaction time of 6 to 24 hours.

7. The method for preparing a MXene-based coating with near-infrared light-induced interactive effect according to claim 1, characterized in that: The dynamic covalent bond is selected from at least one of a Diels-Alder bond, a disulfide bond, a diselenide bond, a Schiff base bond, an oxime-carbamate bond, an acylhydrazone bond, and a phenol-carbamate bond.

8. The method for preparing a MXene-based coating with near-infrared light-induced interactive effect according to claim 7, characterized in that: The thermally reversible coating containing dynamic covalent bonds is a Diels-Alder bond type thermally reversible waterborne polyurethane.

9. The method for preparing a MXene-based coating with near-infrared light-induced interactive effect according to claim 7, characterized in that: The mass ratio of the nano-microcapsule to the thermally reversible coating containing dynamic covalent bonds and the curing agent is 1:(1-100):(1-100).

10. A MXene-based coating with near-infrared light-induced interactive effect, prepared by the method described in any one of claims 1 to 9.

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