Self-healing microcapsule silane composite and method of making and use thereof

Abstract

The application discloses a self-repairing microcapsule silane composite, a preparation method thereof and application thereof. The preparation method comprises the following steps: preparing a urea-formaldehyde resin prepolymer solution, preparing a core material emulsion of benzotriazole and cerium nitrate, mixing and reacting the urea-formaldehyde resin prepolymer solution and the core material emulsion to prepare microcapsules, and dispersing the microcapsules and polyethylene-methacrylic acid as a healing agent into silane to obtain the self-repairing microcapsule silane composite. The application adopts urea-formaldehyde resin as a carrier, the core material comprises benzotriazole and cerium nitrate, polyethylene-methacrylic acid is used as a healing agent, and the composite is used to form a film to serve as a corrosion-resistant film layer of an NdFeB permanent magnet alloy material. The composite film formed by the application has good corrosion resistance and self-repairing performance, and has a certain self-healing effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of self-repairing microcapsules and their silane composite film materials, in particular to a self-repairing microcapsule for sintered NdFeB surface and a preparation method of a silane composite film thereof. BACKGROUND

[0002] Neodymium-iron-boron (NdFeB) permanent magnet alloy is a high energy density energy storage material, through which energy and information can be efficiently converted. Therefore, NdFeB material has been widely used in many fields such as motor, communication, instrument control, 3C electronics, lithography machine, electronic information and 5G supporting application. However, due to its preparation process, structure and application environment, NdFeB is prone to corrosion.

[0003] Silanization treatment process as a new and environmentally friendly metal material protection technology has attracted the attention of researchers. However, due to the problems of thin silane film thickness, easy cracking and adhesion, its wide application is limited. The methods of mixing and hydrolyzing different types of silanes, adding nanoparticles and organic-inorganic corrosion inhibitors can increase the density of silane film layer and enhance its corrosion resistance.

[0004] The Chinese patent publication specification with application number 202011617630.5 discloses a nanoparticle-doped porous graphene / rare earth multilayer composite silane film and its electrodeposition preparation method and application. The preparation method is as follows: first, mix and hydrolyze silane coupling agent, ethanol and water to obtain a hydrolysis solution; then take the hydrolysis solution and add porous graphene and rare earth salt to obtain a first electrodeposition solution, and take another hydrolysis solution and add nanoparticles to obtain a second electrodeposition solution; use chronocoulometry to deposit the first electrodeposition solution and the second electrodeposition solution on the metal substrate step by step to obtain a nanoparticle-doped porous graphene / rare earth multilayer composite silane film. The film layer can enhance the corrosion resistance of the metal to some extent, but due to the inherent pore defects of the film layer, accidental damage and scratches or aging during use, the physical barrier function will gradually weaken, causing the metal to be exposed to the corrosion environment and corroded, and long-term corrosion protection cannot be achieved.

[0005] Therefore, intelligent self-repairing corrosion protection coatings have been developed, which can also protect the substrate metal when the coating system is damaged. Among them, embedding microcapsules in the coating matrix is a mature method of corrosion protection and self-repairing. Self-repairing microcapsules are mainly divided into organic polymer wall corrosion protection microcapsules, inorganic nano-containers and organic-inorganic hybrid wall microcapsules. Ramay Patra et al. prepared a silane coating loaded with corrosion inhibitor modified by inorganic nano-containers on the surface of low carbon steel, which enhanced the corrosion resistance of low carbon steel. However, the compatibility of inorganic nano-containers with the coating is low, the repair timeliness is insufficient, multiple repairs cannot be achieved, and excessive addition will deteriorate the protective performance of the coating. SUMMARY

[0006] (I) Technical problems to be solved

[0007] The main technical problem to be solved by the present application is that the existing microcapsule composite film for corrosion protection has poor repair timeliness and cannot be repaired multiple times.

[0008] The present application also aims to solve the problem of poor adhesion of the existing solid material corrosion protection film.

[0009] (II) Technical solutions

[0010] To solve the above technical problems, the present application provides a self-repairing microcapsule silane composite, which comprises silane and microcapsules and healing agent dispersed in the silane, the microcapsules comprising a carrier and a core material, the carrier comprising urea-formaldehyde resin; the core material comprising benzotriazole and cerium nitrate as self-repairing agents; and the healing agent being polyethylene-methacrylic acid.

[0011] The present application provides a preparation method of a self-repairing microcapsule silane composite, which comprises silane and microcapsules dispersed in the silane, the microcapsules comprising a carrier and a core material. The preparation method comprises the following steps: preparing a urea-formaldehyde resin prepolymer solution; preparing a core material emulsion, the core material emulsion containing benzotriazole and cerium nitrate; mixing and reacting the urea-formaldehyde resin prepolymer solution and the core material emulsion to prepare microcapsules, the microcapsules comprising a carrier and a core material, the carrier comprising urea-formaldehyde resin, and the core material being benzotriazole and cerium nitrate as self-repairing agents; and dispersing the microcapsules and polyethylene-methacrylic acid as a healing agent into silane to obtain a self-repairing microcapsule silane composite.

[0012] According to a preferred embodiment of the present application, in the preparation of the urea-formaldehyde resin prepolymer solution, a urea-formaldehyde solution is used for reaction.

[0013] According to a preferred embodiment of the present application, in the preparation of the core material emulsion, sodium dodecyl sulfonate and / or polyvinyl alcohol are used as emulsifiers, and benzotriazole and cerium nitrate are added to the emulsifiers before emulsification.

[0014] According to a preferred embodiment of the present application, in the preparation of the microcapsules, a curing agent is added after the mixing of the urea-formaldehyde resin prepolymer solution and the core material emulsion, or a curing agent and a curing accelerator are added.

[0015] According to a preferred embodiment of the present application, a defoaming agent is added after the mixing of the urea-formaldehyde resin prepolymer solution and the core material emulsion.

[0016] The third aspect of the present application provides a method for forming a self-repairing microcapsule silane composite multilayer film on the surface of a solid material, characterized in that it comprises the following steps: performing plasma treatment on the surface of the solid material to harden the surface; preparing a self-repairing microcapsule silane composite using the method for preparing a self-repairing microcapsule silane composite;

[0017] using the self-repairing microcapsule silane composite, preparing a self-repairing microcapsule silane composite film on the surface of the solid material by using an electrochemical assisted deposition sol-gel method;

[0018] adding self-repairing microcapsules into an epoxy polymer to form a microcapsule-epoxy composite, and spin-coating the microcapsule-epoxy composite on the surface of the self-repairing microcapsule silane composite to form a microcapsule-epoxy coating, so as to form a self-repairing microcapsule silane composite multilayer film on the surface of the solid material.

[0019] According to a preferred embodiment of the present application, the solid material is an NdFeB permanent magnet alloy.

[0020] The fourth aspect of the present application provides a use of a self-repairing microcapsule silane composite as a corrosion-resistant film layer on the surface of a solid material.

[0021] (III) Beneficial Effects

[0022] The use of the self-repairing microcapsule silane composite of the present application as a corrosion-resistant film layer on the surface of a solid material has good corrosion resistance and self-repairing performance, and has little effect on magnetic properties, and can be used for the surface corrosion protection of NdFeB permanent magnet alloy materials and the like.

[0023] The self-repairing microcapsule silane composite of the present application as a corrosion-resistant film layer on the surface of a solid material has a certain self-healing effect.

[0024] The microcapsules in the self-repairing microcapsule silane composite of the present application can be uniformly dispersed in the silane, and the formed corrosion-resistant film layer is uniform and dense as a whole, without obvious defects.

[0025] The method for preparing the self-repairing microcapsule silane composite of the present application has the characteristics of simple process, short preparation time, low toxicity and high stability.

[0026] The corrosion-resistant film layer formed by using the method for forming a self-repairing microcapsule silane composite film on the surface of a solid material of the present application has the advantages of strong adhesion and not easy to fall off. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a flow chart of the method for preparing a self-repairing microcapsule silane composite of the present application.

[0028] Figure 2This is a flowchart of the method for forming a self-healing microcapsule silane composite film on the surface of a solid material according to the present invention.

[0029] Figure 3 The electrochemical impedance spectroscopy diagrams are of the products and substrates prepared in Examples 2, 1, and 3 of this invention.

[0030] Figure 4 The electrochemical polarization curves of the products and substrates prepared in Examples 2, 1, 2 and 3 of this invention are shown in the test diagrams.

[0031] Figure 5 The image is a SEM image obtained from linear scanning analysis of the product prepared in Example 2 of the present invention.

[0032] Figure 6 The EDS image is obtained from the linear scan analysis of the product prepared in Example 2 of the present invention.

[0033] Figure 7 The elemental distribution map is obtained from linear scanning analysis of the product prepared in Example 2 of the present invention. Detailed Implementation

[0034] The self-healing microcapsule silane complex upon which this invention is based comprises silane and microcapsules dispersed within the silane, wherein the microcapsules include a carrier and a core material. To address the aforementioned technical problems, this invention proposes using benzotriazole (BTA) and cerium nitrate (in a 1:1 ratio) as corrosion inhibitors, i.e., as the core material of the microcapsules. BTA is an organic corrosion inhibitor (organic inhibitor), and its corrosion inhibition consists of two steps. First, the inhibitor is transferred to the metal surface; second, the inhibitor molecules interact with the metal surface. When a metal comes into contact with a corrosive substance and corrosion occurs, a positive charge gradually accumulates on the metal surface. Cl... - SO4 2- NO2 - Anions, attracted by positive charges, adsorb onto the metal surface. Organic inhibitors exhibit cationic properties in corrosive solutions. Due to physicostatic adsorption, corrosive anions attract organic inhibitor molecules, but a layer of corrosive anions exists between the metal surface and the inhibitor molecules. Subsequently, the organic inhibitor molecules adsorb onto the metal surface. The polar end of the inhibitor forms a coordination bond with the metal through shared electrons. The nonpolar tail faces the solution, ultimately forming a passivation film on the metal surface, hindering the corrosion reaction. Cerium ions (Ce)... 3+ The outermost and penultimate electron shells have numerous empty orbitals, exhibiting strong coordination ability and increasing the coverage of the organic inhibitor BTA molecules on the metal substrate surface. Taking iron-containing materials as an example, the relevant self-healing mechanism of this invention is as follows:

[0035] Fe + BTA → Fe-BTA ads

[0036] Fe 2+ + BTA → Fe(II)BTA

[0037]

[0038] In the above formula, BTA ads represents benzotriazole molecules adsorbed on the surface of the metal, and Fe(II)BTA represents a chelate formed by benzotriazole molecules coordinated with divalent iron. Since the silane film has the disadvantages of thin film layer and easy cracking, the corrosion medium (Cl - , O2, H2O) in the solution easily penetrates into the film through the cracks, and when Cl - penetrates into the iron matrix, the inhibitor in the microcapsule is released, and the loaded BTA molecules form a complex with the NdFeB matrix, forming a dense protective film that repairs the film layer. On the other hand, cerium ions Ce 3+ , as an anion precipitation inhibitor, react with OH - to form hydroxide at the interface of the metal solution, inhibiting further development of corrosion.

[0039] The carrier of the microcapsule proposed by the present application is also one of the key points. As the carrier of the microcapsule loaded with the corrosion inhibitor benzotriazole (BTA) and cerium nitrate, the present application uses urea-formaldehyde resin as the basic component of the carrier. The hydroxyl groups on the surface of the carrier are dehydrogenated with silicon oxide, so there is a chemical adsorption effect on the interface, which makes the microcapsule well incorporated into the silane film layer.

[0040] In addition, the silane composite film layer also includes polyethylene-methacrylic acid as a healing agent, so that the silane composite film not only has corrosion inhibition effect, but also has certain self-healing performance. Polyethylene-methacrylic acid contains dynamic chemical bonds that can undergo reversible reactions, such as hydrogen bonds, etc. When the material is damaged, these dynamic chemical bonds break and recombine, thereby repairing the damaged area. In addition, thermal repair is also a feasible self-repairing method. By external heating, the material reaches a certain temperature, the repair agent melts and flows to the crack to fill the defect, and then solidifies to form a new connection during the cooling process.

[0041] The present application also proposes a method for preparing a self-repairing microcapsule silane composite. Figure 1 is a flow chart of the method for preparing a self-repairing microcapsule silane composite of the present application. As Figure 1As shown, the method of the present application comprises: S1, preparing a urea-formaldehyde resin prepolymer solution; S2, preparing a core material emulsion, the core material emulsion comprising benzotriazole and cerium nitrate; S3, mixing and reacting the urea-formaldehyde resin prepolymer solution and the core material emulsion to prepare microcapsules, the microcapsules comprising a carrier and a core material, the carrier comprising urea-formaldehyde resin, and the core material being benzotriazole and cerium nitrate as a self-repairing agent; S4, dispersing the microcapsules and polyethylene-methacrylic acid as a healing agent into silane to obtain a self-repairing microcapsule silane composite.

[0042] In the step, the reaction raw material (or prepolymer) is added into the reaction medium (core material emulsion / continuous phase). Since the reaction raw material (or prepolymer) is soluble in the medium, and its polymer is insoluble in the whole system, the polymerization reaction occurs at the interface between the dispersed phase and the continuous phase. As the reaction continuously proceeds, the reaction raw material gradually polymerizes, and when the reaction product reaches a certain amount, it gradually deposits on the surface of the core material.

[0043] In addition, the present application preferably uses sodium dodecyl sulfonate and polyvinyl alcohol as emulsifiers, ammonium chloride as a curing agent, and resorcinol as a curing accelerator.

[0044] The present application also proposes to use the self-repairing microcapsule silane composite film formed on the surface of the solid material of the present application. Figure 2 is a flow chart of the method of the present application for forming a self-repairing microcapsule silane composite film on the surface of a solid material. As shown, Figure 2 As shown, the method for forming a self-repairing microcapsule silane composite film comprises: step T1, plasma treating the surface of the solid material to harden the surface; T2, using the method for preparing a self-repairing microcapsule silane composite to prepare a self-repairing microcapsule silane composite; T3, using the self-repairing microcapsule silane composite to prepare a self-repairing microcapsule silane composite film on the surface of the solid material; T4, adding self-repairing microcapsules into an epoxy polymer to form a microcapsule-epoxy composite, and spin coating the microcapsule-epoxy composite on the surface of the self-repairing microcapsule silane composite film to form a microcapsule-epoxy coating, so as to form a self-repairing microcapsule silane composite multilayer film on the surface of the solid material.

[0045] In step T3, the microcapsule silane composite film is preferably prepared on the surface of the solid material by using an electrochemical assisted deposition sol-gel method, and then dried.

[0046] In step T4, the microcapsule-epoxy coating is preferably prepared on the surface by using a spin coating method, so as to form a self-repairing microcapsule silane composite multilayer film on the surface of the solid material and improve the adhesion, and the corrosion resistance is also improved.

[0047] In the process, the silanol molecules formed by hydrolysis of silane and the surface hydroxyl groups of the solid material undergo dehydration condensation reaction to form Si-O-Fe bond (taking Fe-containing material as an example).

[0048] Before forming the self-repairing microcapsule silane composite film, the surface of the solid material is also subjected to plasma treatment to harden the surface, because of etching of the material surface, formation of a dense crosslinked layer or introduction of oxygen-containing polar groups, such treatment not only improves the energy of the material surface, but also improves the spreading performance of the surface, reduces the generation of bubbles, according to the diffusion theory, the increase of wettability promotes the improvement of the bonding strength. Thus the bonding force of the self-repairing microcapsule silane composite film and the solid material can be enhanced.

[0049] In addition, the electrochemical assisted deposition method is used in film formation, and in the process, the silanol monomers form a tight three-dimensional network structure through condensation reaction between silanol monomers with silane oxide bridge as the connection, which can hinder the penetration of surrounding corrosive substances and provide short-term barrier protection.

[0050] The application also proposes the use of the self-repairing microcapsule silane composite as a corrosion-resistant film layer on the surface of the solid material. The solid material can be NdFeB permanent magnet alloy, because the self-repairing microcapsule silane composite layer of the application has little effect on the magnetic properties.

[0051] In order to make the purpose, technical scheme and advantages of the application more clear and explicit, the application will be further described in detail below with reference to the specific examples and the accompanying drawings.

[0052] Example 1

[0053] Example 1 is the process step of preparing the self-repairing microcapsule silane composite of the application. The process step includes:

[0054] (1) Take 5g urea and 10g formaldehyde solution (37wt.%) and add them to a three-necked flask, stir and dissolve, adjust the pH value to 8 with triethanolamine, adjust the stirring speed, heat in a 70℃ water bath for 1h, cool to room temperature, and obtain the urea-formaldehyde resin prepolymer M1 for use.

[0055] (2) Take 15ml of 10wt.% sodium dodecyl sulfonate and 135ml of deionized water and mix them in a three-necked flask, take 2g of benzotriazole and 2g of cerium nitrate hexahydrate and add them, emulsify and stir at 65℃ for 35min, and obtain the core material emulsion M2.

[0056] The sodium dodecyl sulfonate in this step is used as an emulsifier, polyvinyl alcohol can also be used, or a mixture of the two can also be used.

[0057] (3) The prepared urea-formaldehyde resin prepolymer Ml was added dropwise into the core material emulsion M2, 0.5 g of resorcinol and 0.5 g of ammonium chloride were added for dissolution, 1 mol / L dilute hydrochloric acid was used to adjust the pH to 3, and n-octanol was added as a defoaming agent. The reaction was carried out at 65 °C and 700 rpm for 2.5 h to obtain an intermediate sample M3.

[0058] (4) The intermediate sample M3 was washed with deionized water, vacuum filtered, and vacuum dried at 45 °C for 6 h to obtain self-repairing microcapsules M4.

[0059] (5) The self-repairing microcapsules M4 and polyethylene-methacrylic acid were ultrasonically dispersed in a silane hydrolysis solution for 30 min to obtain a microcapsule silane mixed solution M5, i.e., a self-repairing microcapsule silane composite.

[0060] Example 2

[0061] Example 2 implements the process steps of forming a self-repairing microcapsule silane composite film on the surface of an NdFeB permanent magnet alloy using the self-repairing microcapsule silane composite prepared in Example 1.

[0062] (1) NdFeB permanent magnet alloy pretreatment: The NdFeB permanent magnet alloy was polished to 800 mesh in stages using a metallographic sandpaper, and then the surface was ultrasonically degreased with acetone for 100 s and ultrasonically derusted with ethanol for 100 s, and the surface was dried with N2.

[0063] (2) The surface of the NdFeB permanent magnet alloy was treated using a plasma surface treatment machine, with argon gas of 99.99% purity as the working gas, a gas flow range of 1 L / min, a frequency of 20 kHz, a power of 600 W, a vertical distance of 10 mm between the nozzle of the spray gun and the surface of the sample, a treatment speed of 5 mm / s, and an arch-shaped reciprocating motion. After the gas pressure stabilized, the discharge power was adjusted and the discharge was started. After a certain period of time, the power was turned off, and the NdFeB permanent magnet alloy sample M6 was obtained.

[0064] (3) The NdFeB permanent magnet alloy sample M6 was immersed in the microcapsule silane mixed solution M5, and a microcapsule silane composite film was prepared by electrochemical assisted deposition.

[0065] The electrochemical assisted deposition was carried out using a three-electrode system (the working electrode was the substrate NdFeB permanent magnet alloy, the reference electrode was a saturated calomel electrode, and the auxiliary electrode was a platinum sheet) with a voltage of -1.5 V, a deposition time of 400 s, and a working temperature of 35 °C. The prepared composite film layer was rinsed with deionized water and dried and cured at 40 °C to obtain sample M7.

[0066] (4) A certain amount of self-repairing microcapsules M4 was added into the epoxy polymer matrix, and the sample was treated with ultrasound at 30 kHz for 10 min. The mixture was placed in a shaker, and then degassed after mixing under vacuum to obtain sample M8.

[0067] (5) A multi-layer composite film was prepared by spin coating: sample M7 was fixed on a spin coater, the rotation speed was adjusted to 1500 r / min, a certain amount of sample M8 was added to the center of sample M7, and a uniform microcapsule-epoxy coating was formed on the surface of sample M7 after rotating for 300 s, and then it was dried to obtain product M9.

[0068] Comparative Example 1

[0069] Compared with Example 2, most of them are the same, but the addition of self-repairing microcapsules loaded with benzotriazole and cerium nitrate and the preparation of multi-layer composite film by spin coating are omitted.

[0070] Comparative Example 2

[0071] Compared with Example 2, most of them are the same, but the addition of self-repairing microcapsules loaded with benzotriazole and cerium nitrate and the preparation of multi-layer composite film by spin coating are omitted.

[0072] Comparative Example 3

[0073] Compared with Example 2, most of them are the same, but the preparation of multi-layer composite film by spin coating is omitted.

[0074] Comparative Example 4

[0075] Compared with Example 2, most of them are the same, but the step of treating NdFeB permanent magnet alloy by plasma is omitted.

[0076] Performance analysis

[0077] A three-electrode system (working electrode: NdFeB substrate, reference electrode: saturated calomel electrode, auxiliary electrode: platinum plate) was immersed in a 3.5 wt.% sodium chloride solution, and the polarization curve and electrochemical impedance spectrum of Example 2 and each comparative example were tested by an electrochemical workstation.

[0078] Figure 3 The electrochemical impedance spectra (EIS, detection equipment: CHI660e electrochemical workstation) of the products prepared by the substrates (NdFeB permanent magnet alloy), Example 2 and Comparative Example 1, Comparative Example 3 in 3.5 wt.% NaCl were obtained. Table 1 is the EIS analysis data (R s : solution resistance; R ct : charge transfer resistance; CPE f : film capacitance; R f : film resistance; CPEdl : double layer capacitor).

[0079] The resistance of the microcapsule silane composite film prepared in Comparative Example 3 was significantly increased compared with the bisilane film and the substrate prepared in Comparative Example 1. It was nearly 2 times of the bisilane film prepared in Comparative Example 1 and nearly 30 times of the substrate. This indicates that the addition of the self-repairing microcapsule significantly improves the corrosion resistance of the silane film. The resistance of the product prepared in Example 2 was nearly 130 times of that of Comparative Example 3, which indicates that the multilayer film significantly improves the corrosion resistance.

[0080] Table 1 EIS fitting data

[0081]

[0082] Figure 4 The electrochemical polarization curves of the substrate (NdFeB permanent magnet alloy), the products prepared in Example 2 and Comparative Examples 1, 2 and 3 in 3.5 wt.% NaCl were tested (the detection equipment was CHI660e electrochemical workstation).

[0083] Table 2 is the electrochemical parameters of the electrochemical polarization measurement. Compared with the products prepared in Comparative Examples 1, 2 and 3, the current density of the product prepared in Example 2 decreased significantly, and the decreasing trend was as follows: substrate < Comparative Example 2 < Comparative Example 1 < Comparative Example 3 < Example 2, which indicates that the self-repairing microcapsule silane composite film of the application has significant corrosion resistance.

[0084] Table 2 electrochemical parameters of electrochemical polarization measurement

[0085] Potential / V i corr (A-cm -2 ) <!-- 6 -->]]> Substrate -0.775 3.673 x 10 -6 ]] Comparative Example 1 -0.729 1.122 x 10 -6 ]]> Comparative Example 2 -0.760 3.057 x 10 -6 ]]> Comparative Example 3 -0.717 2.42 x 10 -7 ]] Example 2 -0.556 1.67 x 10 -8 ]]

[0086] Figure 5 The morphology of the scratch area of the self-repairing microcapsule multilayer silane composite film prepared in Example 2 was observed. The corrosion inhibitor forms a chelate by chemical reaction with the substrate in the scratch area, which acts as a protective film to inhibit the further transmission of corrosive substances, achieving the effect of self-repairing.

[0087] Figure 6 The EDS spectrum of the scratch area was observed, and the peaks corresponding to N and Ce elements were detected at the scratch, which indicates the successful release of the corrosion inhibitor at the scratch.

[0088] Figure 7 The element distribution obtained by line scanning analysis in the scratch area was observed. Compared with the defect-free part, the intensity of O and Si elements in the defect area was significantly reduced, indicating that the scratch test completely destroyed the silane coating. The content of Ce and N elements was large, indicating that the corrosion inhibitor was released from the self-repairing microcapsule and migrated to the scratch area, playing a self-repairing role.

[0089] The adhesion of the film layer is an important parameter of its performance, and has an important influence on the protection performance of the film layer. In actual application, the adhesion of the film layer is continuously reduced with the passage of time, resulting in peeling or even falling off of the film layer. The adhesion of the film layer is tested according to GB / T9286-1998 "Cross-cut test for dried coatings of paints and varnishes". The specific experimental steps are as follows: a knife is used to draw a grid on the surface of the sample, the grid is perpendicular to each other, then a soft brush is used to gently brush the surface along the diagonal direction, and the surface impurities are cleaned. Then the 3M adhesive tape is adhered to the surface of the sample, and the adhesive tape is quickly torn along the scratch direction, and the peeling of the coating at the edge of the square is observed, and the obtained grade is shown in Table 3.

[0090] Table 3: Adhesion test grade

[0091] Bonding Force Grade Comparative Example 1 4th Grade Comparative Example 3 3rd Grade Comparative Example 4 1st Grade Example 2 0th Grade

[0092] Through the introduction of the above examples, the beneficial effects of the present application compared with the prior art are as follows:

[0093] (1) The microcapsule core material corrosion inhibitor prepared by the present application is in the form of a combination of organic inhibitors and inorganic inhibitors. The organic inhibitor has good corrosion inhibition effect on copper, steel and other metals, and the N-heterocycle of the N heteroatom in the molecular structure of the organic inhibitor can be effectively adsorbed on the metal surface to form a chelate with the metal. At the same time, rare earth salts are added, which are oxidized by oxygen to form oxides, and the cracks are healed due to the volume expansion, such as cerium oxide, yttrium oxide, etc. The Ce 3+ The outermost layer and the next outer electron layer have more empty orbitals, have strong coordination ability, and can increase the coverage of the organic corrosion inhibitor BTA molecules on the surface of the metal substrate, thereby inhibiting corrosion and playing a self-repairing role.

[0094] (2) The microcapsule silane composite film prepared by the present application has a certain self-healing effect, and the urea-formaldehyde microcapsules can be uniformly dispersed in the composite silane film layer.

[0095] (3) The method for preparing the microcapsule silane composite film layer has the characteristics of simple process, short preparation time, low toxicity and high stability.

[0096] The above specific embodiments further illustrate the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only for specific embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A self-healing microcapsule silane complex, comprising silane, microcapsules dispersed in the silane, and a healing agent, wherein the microcapsules comprise a carrier and a core material, characterized in that: The carrier is urea-formaldehyde resin; The core material includes benzotriazole and cerium nitrate as self-healing agents; The healing agent is polyethylene-methacrylic acid.

2. A method for preparing a self-healing microcapsule silane complex, the complex comprising silane and microcapsules dispersed in the silane, the microcapsules comprising a carrier and a core material, characterized in that, The preparation method includes the following steps: Preparation of urea-formaldehyde resin prepolymer solution; A core material emulsion is prepared, wherein the core material emulsion comprises benzotriazole and cerium nitrate; The urea-formaldehyde resin prepolymer solution and the core material emulsion are mixed and reacted to prepare microcapsules. The microcapsules include a carrier and a core material. The carrier includes urea-formaldehyde resin, and the core material is benzotriazole and cerium nitrate as self-healing agents. Microcapsules and polyethylene-methacrylic acid as a healing agent were dispersed in silane to obtain a self-healing microcapsule silane complex.

3. The method for preparing the self-healing microcapsule silane complex as described in claim 2, characterized in that, In preparing the urea-formaldehyde resin prepolymer solution, urea and formaldehyde solution are reacted together.

4. The method for preparing the self-healing microcapsule silane complex as described in claim 2, characterized in that, In preparing the core material emulsion, sodium dodecyl sulfonate and / or polyvinyl alcohol are used as emulsifiers, and benzotriazole and cerium nitrate are added to the emulsifiers before emulsification.

5. The method for preparing the self-healing microcapsule silane complex as described in claim 2, characterized in that, In the preparation of microcapsules, after mixing the urea-formaldehyde resin prepolymer solution and the core material emulsion, a curing agent is added, or a curing agent and a curing accelerator are added.

6. The method for preparing the self-healing microcapsule silane complex as described in claim 5, characterized in that, After mixing the urea-formaldehyde resin prepolymer solution and the core material emulsion, an antifoaming agent is also added.

7. A method for forming a self-healing microcapsule silane composite multilayer film on the surface of a solid material, characterized in that, Includes the following steps: The surface of the solid material is subjected to plasma treatment to harden the surface; The self-healing microcapsule silane complex was prepared using the preparation method of the self-healing microcapsule silane complex as described in any one of claims 2 to 6; Using the self-healing microcapsule silane composite, a self-healing microcapsule silane composite film was prepared on the surface of the solid material by electrochemically assisted deposition using a sol-gel method. Self-healing microcapsules are added to an epoxy polymer to form a microcapsule-epoxy composite. The microcapsule-epoxy composite is then spin-coated onto the surface of the self-healing microcapsule silane composite film to form a microcapsule-epoxy coating, thereby forming a self-healing microcapsule silane composite multilayer film on the surface of the solid material.

8. The method for forming a self-healing microcapsule silane composite multilayer film on the surface of a solid material as described in claim 7, characterized in that, The solid material is an NdFeB permanent magnet alloy.

9. The use of the self-healing microcapsule silane composite of claim 1 as an anti-corrosion film layer on the surface of a solid material.

10. The use of the self-healing microcapsule silane composite as described in claim 9 as an anti-corrosion film layer on the surface of solid materials, characterized in that, The solid material is an NdFeB permanent magnet alloy.

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