Ce-mof / basalt fiber heterojunction, anticorrosive coating and preparation method and application thereof

Abstract

The application discloses a Ce-MOF / basalt fiber heterojunction, anticorrosive paint and a preparation method and application thereof. The preparation method of the Ce-MOF / basalt fiber heterojunction comprises the following steps: pretreating basalt fiber, assembling Ce particles, and preparing the basalt fiber with the surface assembled with the Ce particles; reacting the basalt fiber with the surface assembled with the Ce particles with an organic ligand, and preparing the basalt fiber with the surface in-situ grown with Ce-MOF; and loading a fluorescent indicator on the surface of the basalt fiber with the surface in-situ grown with the Ce-MOF, and preparing the Ce-MOF / basalt fiber heterojunction. In the application, the Ce-MOF is used to improve the interface bonding between the fiber and the epoxy, the barrier property and the repairing property, the fluorescent indicator is used to produce a fluorescent response to the local pH change caused by corrosion or damage, early damage of the coating is visualized and early warning is realized, and the application is suitable for the corrosion protection of metals in the marine high-salt, high-humidity, erosion and other multi-factor coupling environments.

Description

Technical Field

[0001] This invention belongs to the field of surface protection technology, specifically relating to a Ce-MOF / basalt fiber heterostructure, an anti-corrosion coating, and its preparation and application. Background Technology

[0002] Offshore wind power, large ports, ships and other marine engineering equipment face long-term combined effects from chloride salt corrosion, alternating wet and dry conditions, wave impact and sand erosion in the splash zone. Traditional anti-corrosion coatings are often damaged by wear and tear caused by wave and sand erosion, which degrades the mechanical properties of the coating. Subsequently, salt accumulates, crystallizes and generates pressure difference in the alternating wet and dry environment, which damages the internal structure of the coating and causes blistering. The combined effect of these two factors causes the coating to fail in a short period of time due to interface peeling, substrate corrosion and other damage, which seriously affects the safe and stable service of marine engineering equipment.

[0003] Existing anti-corrosion coatings typically enhance their passivation, barrier, and mechanical properties by adding corrosion inhibitors, layered materials, or fibrous materials. Furthermore, in-situ growth of nanoparticles on fiber surfaces can improve the interfacial bonding between fibers and resins. These strategies primarily passively improve the protective performance of composite coatings by constructing interfacial layers or introducing corrosion inhibitors, lacking the ability to actively detect and provide early warning of early damage to the coating.

[0004] For marine engineering equipment, if early damage is not identified in time, the anti-corrosion coating will rapidly fail under the continuous influence of multiple factors such as salinity, alternating wet and dry conditions, wave impact, and sand erosion, making it difficult for the metal equipment to achieve long service life and high reliability. Therefore, there is an urgent need for a multifunctional anti-corrosion coating that can improve mechanical strength and corrosion resistance while providing timely early warning of early damage.

[0005] Therefore, in response to the urgent need for high-performance anti-corrosion coating materials in harsh marine environments, especially in the splash zone, Ce-MOF material based on pH fluorescent indicators is grown in situ on the fiber surface to endow the coating with excellent mechanical, passivation repair and early damage warning properties, thereby achieving long-term corrosion protection in harsh marine environments, especially in the splash zone. Summary of the Invention

[0006] The main objective of this invention is to provide a Ce-MOF / basalt fiber heterostructure, an anti-corrosion coating, and its preparation and application, so as to overcome the shortcomings of the prior art.

[0007] To achieve the aforementioned objectives, the technical solution adopted by this invention includes: This invention provides a method for preparing Ce-MOF / basalt fiber heterojunctions, comprising: Surface-activated basalt fibers were obtained by pretreatment of basalt fibers. Ce particles are assembled on the surface-activated basalt fibers to obtain basalt fibers with surface-assembled Ce particles. The basalt fibers with Ce particles assembled on the surface are reacted with organic ligands to obtain basalt fibers with Ce-MOF grown in situ on the surface. Furthermore, a fluorescent indicator was loaded onto the surface of Ce-MOF basalt fibers grown in situ on the surface to prepare a Ce-MOF / basalt fiber heterojunction.

[0008] The present invention also provides a Ce-MOF / basalt fiber heterostructure prepared by the aforementioned preparation method, comprising: surface-activated basalt fibers as a carrier, Ce-MOF grown in situ on the surface of the carrier, and a fluorescent indicator loaded on the surface of the carrier.

[0009] This invention also provides a Ce-MOF / basalt fiber heterostructure modified anticorrosive coating, which includes: component A and component B, wherein component A includes the aforementioned Ce-MOF / basalt fiber heterostructure and epoxy powder; and component B includes additives and curing agents.

[0010] This invention also provides a method for preparing a Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating, comprising: Provide the aforementioned Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating; Ce-MOF / basalt fiber heterojunctions are mechanically mixed with epoxy powder to form component A; curing agent and additives are mixed and stirred to form component B. Furthermore, the components A and B are ball-milled and mixed, applied to the surface of a metal substrate by electrostatic spraying, and cured to obtain a Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating.

[0011] The present invention also provides a Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating prepared by the aforementioned preparation method.

[0012] The embodiments of the present invention also provide the application of the aforementioned Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating and Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating in corrosion protection of metal equipment in marine high-salt, high-humidity, and erosion multi-factor coupled environments.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The Ce-MOF grown in situ on the surface of basalt fiber prepared by the present invention can significantly enhance the interfacial bonding strength between the fiber and the epoxy substrate, and can effectively improve the structural stability of the coating in the splashing environment.

[0014] (2) The Ce-MOF-loaded fluorescent indicator prepared by the present invention, which is grown in situ on basalt fibers, can sense local pH changes and give the coating an early warning capability.

[0015] (3) The anti-corrosion coating prepared by the present invention exhibits excellent resistance to mechanical impact and corrosion resistance under the coupled environment of high salt, alternating wet and dry conditions and sand scouring in the splash zone, and can provide long-term protection for metal equipment. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figures 1a-1b This is a SEM image and an EDS energy spectrum of characteristic elements of basalt fibers with Ce-MOF grown in situ on the surface and loaded with isothiocyanate in Example 1 of this invention. Figure 2 This is a diagram showing the maximum erosion depth of the Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating in the simulated wave splash zone in Example 1 of this invention. Figure 3 This is a diagram showing the maximum erosion depth of the Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating in the simulated wave splash zone in Embodiment 2 of the present invention. Figure 4 This is a diagram showing the maximum erosion depth of the Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating in the simulated wave splash zone in Example 3 of the present invention. Figure 5 This is a diagram showing the maximum erosion depth of the Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating in the simulated wave splash zone in Comparative Example 1 of this invention. Figure 6 This is a diagram showing the maximum erosion depth of the Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating in the simulated wave splash zone in Comparative Example 2 of this invention. Figure 7 This is a diagram showing the maximum erosion depth of the Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating in the simulated wave splash zone in Comparative Example 3 of the present invention. Detailed Implementation

[0018] In view of the deficiencies of the prior art, the applicant, through long-term research and extensive practice, has proposed the technical solution of this invention. The technical solution of this invention will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0019] Specifically, as one aspect of the technical solution of this invention, a method for preparing a Ce-MOF / basalt fiber heterostructure includes: Surface-activated basalt fibers were obtained by pretreatment of basalt fibers. Ce particles are assembled on the surface-activated basalt fibers to obtain basalt fibers with surface-assembled Ce particles. The basalt fibers with Ce particles assembled on the surface are reacted with organic ligands to obtain basalt fibers with Ce-MOF grown in situ on the surface. Furthermore, a fluorescent indicator was loaded onto the surface of Ce-MOF basalt fibers grown in situ on the surface to prepare a Ce-MOF / basalt fiber heterojunction.

[0020] In some preferred embodiments, the preparation method specifically includes: (1) Basalt fibers were pretreated with acetone, alkaline solution and hydrogen peroxide in sequence to obtain surface-activated basalt fibers; (2) Dissolve the cerium-containing metal precursor in ethanol, then add the surface-activated basalt fiber and stir at 10℃~50℃ for 6h-18h. After washing and drying, basalt fiber with Ce particles assembled on the surface is obtained. (3) Mix the organic ligand with water and ethanol and adjust the pH value to 7.5~10.5. Then mix it with the basalt fiber with Ce particles assembled on the surface and stir at 10℃~50℃ for 6h-18h. Then wash and dry to obtain basalt fiber with Ce-MOF grown in situ on the surface. (4) Dissolve the fluorescent indicator in ethanol, add the basalt fiber with Ce-MOF grown in situ on the surface, and react at 60℃~95℃ for 6h-18h. Then wash and dry to obtain basalt fiber with Ce-MOF grown in situ on the surface and loaded with fluorescent indicator, i.e., the Ce-MOF / basalt fiber heterojunction.

[0021] Furthermore, the alkaline solution includes any one or more combinations of sodium hydroxide solution, potassium hydroxide solution, and ammonia solution, and is not limited thereto.

[0022] Furthermore, the cerium-containing metal precursor includes any one or more combinations of cerium chloride, cerium sulfate, and cerium nitrate, but is not limited thereto.

[0023] Furthermore, the organic ligand includes, but is not limited to, any one or more combinations of cysteine, terephthalic acid, 2,5-furandicarboxylic acid, pyromellitic acid, and pyromellitic tetracarboxylic acid.

[0024] Furthermore, the fluorescent indicator includes any one or more combinations of isothiocyanates, coumarins, rhodamine derivatives, and fluorescein derivatives, and is not limited thereto.

[0025] Furthermore, in step (1), the average diameter of the basalt fiber is 4-20 μm.

[0026] Further, in step (2), the mass ratio of the cerium-containing metal precursor to the surface-activated basalt fiber is 1:5 to 1:15.

[0027] Further, in step (3), the volume ratio of ethanol to water is 1:(0.1~2).

[0028] Further, in step (3), the mass ratio of the organic ligand to the basalt fiber of the surface-assembled Ce particles is 1:5 to 1:15.

[0029] Further, in step (4), the mass ratio of the fluorescent indicator to the basalt fiber of Ce-MOF grown in situ on the surface is 2:1 to 1:2.

[0030] In some preferred embodiments, the preparation method of the Ce-MOF / basalt fiber heterojunction includes the following steps: (a) Surface pretreatment of basalt fiber: Basalt fiber is mixed with acetone, stirred, refluxed and washed at 75°C and dried; then sodium hydroxide solution is added, stirred at 60°C for 30 minutes, washed until neutral and dried; further, 5% hydrogen peroxide is added, stirred for 3 hours and washed until neutral to obtain surface-activated basalt fiber.

[0031] (b) Assembling Ce particles on the surface of basalt fibers: Weigh a certain amount of cerium-containing metal precursor, dissolve it fully in anhydrous ethanol, then add the activated basalt fibers, stir the reaction thoroughly, wash with deionized water, and dry at 60°C to obtain basalt fibers with Ce particles assembled on the surface.

[0032] (c) In-situ growth of Ce-MOF on basalt fibers: A certain amount of organic ligands was weighed and dissolved in a mixed solution of anhydrous ethanol and deionized water. The pH of the solution was adjusted to 9 using sodium hydroxide. The solution was added dropwise to the solution in (b). The reaction was stirred thoroughly. The solution was washed with deionized water and dried at 60°C to obtain basalt fibers with Ce-MOF grown in situ on the surface.

[0033] (d) In-situ growth of Ce-MOF loaded with fluorescent indicator on basalt fiber: The fluorescent indicator was dissolved in anhydrous ethanol and added to the basalt fiber in which Ce-MOF was grown in situ on the surface. The reaction was carried out at 80°C for 12 hours. The fiber was washed by centrifugation with deionized water and dried at 60°C to obtain basalt fiber in which Ce-MOF was grown in situ on the surface and loaded with fluorescent indicator.

[0034] Another aspect of the present invention provides a Ce-MOF / basalt fiber heterostructure prepared by the aforementioned preparation method, comprising: surface-activated basalt fibers as a carrier, Ce-MOF grown in situ on the surface of the carrier, and a fluorescent indicator loaded on the surface of the carrier.

[0035] Another aspect of the present invention provides a Ce-MOF / basalt fiber heterostructure modified anticorrosive coating, comprising: component A and component B, wherein component A comprises the aforementioned Ce-MOF / basalt fiber heterostructure and epoxy powder; and component B comprises additives and curing agents.

[0036] In some preferred embodiments, the Ce-MOF / basalt fiber heterojunction content in the Ce-MOF / basalt fiber heterojunction modified anticorrosive coating is 1~5wt%.

[0037] In some preferred embodiments, the epoxy powder content in the Ce-MOF / basalt fiber heterostructure modified anticorrosive coating is 80~95wt%.

[0038] In some preferred embodiments, the content of additives in the Ce-MOF / basalt fiber heterostructure modified anticorrosive coating is 0.5~1.5wt%.

[0039] In some preferred embodiments, the curing agent content in the Ce-MOF / basalt fiber heterostructure modified anticorrosive coating is 2~10wt%.

[0040] In some preferred embodiments, the epoxy powder includes any one or more combinations of bisphenol A type epoxy, phenolic epoxy, and alicyclic epoxy, but is not limited thereto.

[0041] In some preferred embodiments, the additives include any one or more combinations of leveling agents, defoamers, and adhesion promoters, but are not limited thereto.

[0042] In some preferred embodiments, the curing agent includes any one or a combination of two of amine curing agents and phenolic curing agents, and is not limited thereto.

[0043] Another aspect of this invention provides a method for preparing a Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating, comprising: Provide the aforementioned Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating; Ce-MOF / basalt fiber heterojunctions are mechanically mixed with epoxy powder to form component A; curing agent and additives are mixed and stirred to form component B. Furthermore, the components A and B are ball-milled and mixed, applied to the surface of a metal substrate by electrostatic spraying, and cured to obtain a Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating.

[0044] In some preferred embodiments, the curing treatment is performed at a temperature of 150°C to 250°C for a time of 0.2 to 1.0 h.

[0045] In some preferred embodiments, the metal substrate includes any one of carbon steel, stainless steel, aluminum alloy, copper alloy, and titanium alloy, but is not limited thereto.

[0046] Another aspect of the present invention provides a Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating prepared by the aforementioned preparation method.

[0047] Another aspect of the present invention provides the application of the aforementioned Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating and Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating in corrosion protection of metal equipment in marine high-salt, high-humidity, and erosion multi-factor coupled environments.

[0048] The technical solution of the present invention will be further described in detail below with reference to several preferred embodiments and accompanying drawings. This embodiment is implemented on the premise of the technical solution of the invention, and provides detailed implementation methods and specific operation processes. However, the protection scope of the present invention is not limited to the following embodiments.

[0049] Unless otherwise specified, the experimental materials used in the examples below can be purchased from conventional biochemical reagent companies.

[0050] Example 1 (1) Surface pretreatment of basalt fiber: 10 g of basalt fiber was mixed with 400 ml of acetone and stirred at 500 r / min at 75℃ for 48 hours and washed, and dried at 80℃ for 24 hours; then a sodium hydroxide solution with a concentration of 2 mol / L was added, stirred at 500 r / min at 60℃ for 30 minutes, washed with deionized water until neutral, and dried at 80℃ for 12 hours; further, it was added to 5% hydrogen peroxide, stirred for 3 hours, and washed with deionized water until neutral to obtain surface-activated basalt fiber.

[0051] (2) In-situ growth of Ce-MOF on basalt fiber surface and loading of isothiocyanate: ① Weigh 0.6210 g of cerium chloride and dissolve it completely in 40 ml of anhydrous ethanol. Then add 4.9676 g of activated basalt fiber and stir the reaction for 12 hours. Wash with deionized water and dry at 60°C to obtain basalt fiber with Ce particles assembled on the surface. ② Weigh 0.6050 g of cysteine ​​and dissolve it in a mixed solution of 40 ml of anhydrous ethanol and 40 ml of deionized water. Adjust the pH of the solution to 9 with 2 mol / L sodium hydroxide and add it dropwise to the above solution. Stir the reaction for 12 hours and wash with deionized water. Dry at 60°C to obtain basalt fiber with Ce-MOF grown in situ on the surface. ③ Dissolve 0.7948 g of isothiocyanate in 40 ml of anhydrous ethanol, and add 0.6210 g of basalt fiber with Ce-MOF grown in situ on the surface. React at 80℃ for 12 hours, wash three times with deionized water by centrifugation, and dry at 60℃ to obtain basalt fiber with Ce-MOF grown in situ on the surface and loaded with isothiocyanate. The SEM morphology of the basalt fiber with Ce-MOF grown in situ on the surface and loaded with isothiocyanate is as follows. Figure 1a As shown, the elemental spectrum is as follows Figure 1b As shown.

[0052] (3) Preparation of composite coating: 2.5 wt.% Ce-MOF / basalt fiber heterojunction was mechanically mixed with 90 wt.% SH-E50 epoxy powder to obtain component A; 7 wt.% SH-500 curing agent and 0.5 wt.% HYC-01 additive were mixed and stirred to obtain component B; then, component A and component B were ball-milled, electrostatically sprayed, and cured at 180℃ for 30 minutes to obtain the anti-corrosion coating. The erosion resistance was tested under the conditions of 25℃, sand content of 20 wt.%, impact angle of 90°, impact pressure of 0.25MPa, and test time of 25 minutes. The maximum erosion depth of the coating surface was 1.71 mm, and the coating mass damage was 0.81 g; the erosion depth diagram is shown in the figure. Figure 2As shown. After immersion in 3.5 wt.% NaCl for 60 days, the low-frequency impedance of the coating was 10. 9 Ω·cm 2 The damaged area of ​​the coating showed a significant fluorescent effect on the fourth day, changing from yellow to green, indicating excellent corrosion early warning function.

[0053] Example 2 (1) Surface pretreatment of basalt fiber: 10 g of basalt fiber was mixed with 400 ml of acetone and stirred at 500 r / min at 75℃ for 48 hours and washed, and dried at 80℃ for 24 hours; then a sodium hydroxide solution with a concentration of 2 mol / L was added, stirred at 500 r / min at 60℃ for 30 minutes, washed with deionized water until neutral, and dried at 80℃ for 12 hours; further, it was added to 5% hydrogen peroxide, stirred for 3 hours, and washed with deionized water until neutral to obtain surface-activated basalt fiber.

[0054] (2) In-situ growth of Ce-MOF on basalt fiber surface and loading of isothiocyanate: ① Weigh 0.6210 g of cerium chloride and dissolve it completely in 40 ml of anhydrous ethanol. Then add 4.9676 g of activated basalt fiber and stir the reaction for 12 hours. Wash with deionized water and dry at 60°C to obtain basalt fiber with Ce particles assembled on the surface. ② Weigh 0.6050 g of cysteine ​​and dissolve it in a mixed solution of 40 ml of anhydrous ethanol and 40 ml of deionized water. Adjust the pH of the solution to 9 with 2 mol / L sodium hydroxide and add it dropwise to the above solution. Stir the reaction for 12 hours and wash with deionized water. Dry at 60°C to obtain basalt fiber with Ce-MOF grown in situ on the surface. ③ Dissolve 0.7948 g of isothiocyanate in 40 ml of anhydrous ethanol, and add 0.6210 g of basalt fiber with Ce-MOF grown in situ on the surface. React at 80℃ for 12 hours, wash three times with deionized water by centrifugation, and dry at 60℃ to obtain basalt fiber with Ce-MOF grown in situ on the surface and loaded with isothiocyanate.

[0055] (3) Preparation of composite coating: 3 wt.% Ce-MOF / basalt fiber heterojunction was mechanically mixed with 89 wt.% SH-E50 epoxy powder to obtain component A; 7 wt.% SH-500 curing agent and 1 wt.% HYC-01 additive were mixed and stirred to obtain component B; then, component A and component B were ball-milled, electrostatically sprayed, and cured at 180℃ for 30 minutes to obtain the anti-corrosion coating. The erosion resistance was tested at 25℃, sand content of 20 wt.%, impact angle of 90°, impact pressure of 0.25 MPa, and test time of 25 minutes. The maximum erosion depth of the coating surface was 1.96 mm, and the coating mass loss was 0.86 g; the erosion depth diagram is shown below. Figure 3 As shown. After immersion in 3.5 wt.% NaCl for 60 days, the low-frequency impedance of the coating was 10. 9 Ω·cm 2 The damaged area of ​​the coating showed a significant fluorescent effect on the fourth day, changing from yellow to green, indicating excellent corrosion early warning function.

[0056] Example 3 (1) Surface pretreatment of basalt fiber: 10 g of basalt fiber was mixed with 400 ml of acetone and stirred at 500 r / min at 75℃ for 48 hours and washed, and dried at 80℃ for 24 hours; then a sodium hydroxide solution with a concentration of 2 mol / L was added, stirred at 500 r / min at 60℃ for 30 minutes, washed with deionized water until neutral, and dried at 80℃ for 12 hours; further, it was added to 5% hydrogen peroxide, stirred for 3 hours, and washed with deionized water until neutral to obtain surface-activated basalt fiber.

[0057] (2) In-situ growth of Ce-MOF on basalt fiber surface and loading of isothiocyanate: ① Weigh 0.6210 g of cerium chloride and dissolve it completely in 40 ml of anhydrous ethanol. Then add 4.9676 g of activated basalt fiber and stir the reaction for 12 hours. Wash with deionized water and dry at 60°C to obtain basalt fiber with Ce particles assembled on the surface. ② Weigh 0.6050 g of cysteine ​​and dissolve it in a mixed solution of 40 ml of anhydrous ethanol and 40 ml of deionized water. Adjust the pH of the solution to 9 with 2 mol / L sodium hydroxide and add it dropwise to the above solution. Stir the reaction for 24 hours and wash with deionized water. Dry at 60°C to obtain basalt fiber with Ce-MOF grown in situ on the surface. ③ Dissolve 0.7948 g of isothiocyanate in 40 ml of anhydrous ethanol, and add 0.6210 g of basalt fiber with Ce-MOF grown in situ on the surface. React at 80℃ for 24 hours, wash three times with deionized water by centrifugation, and dry at 60℃ to obtain basalt fiber with Ce-MOF grown in situ on the surface and loaded with isothiocyanate.

[0058] (3) Preparation of composite coating: 3 wt.% Ce-MOF / basalt fiber heterojunction was mechanically mixed with 89.5 wt.% SH-E50 epoxy powder to obtain component A; 7 wt.% SH-500 curing agent and 0.5 wt.% HYC-01 additive were mixed and stirred to obtain component B; then, component A and component B were ball-milled, electrostatically sprayed, and cured at 180℃ for 60 minutes to obtain the anti-corrosion coating. The erosion resistance was tested under the conditions of 25℃, 20 wt.% sand content, 90° impact angle, 0.25MPa impact pressure, and 25 minutes. The maximum erosion depth of the coating surface was 2.04 mm, and the coating mass damage was 0.89 g; the erosion depth diagram is shown below. Figure 4 As shown. After immersion in 3.5 wt.% NaCl for 60 days, the low-frequency impedance of the coating was 10. 8 Ω·cm 2 .

[0059] Comparative Example 1 (1) Surface pretreatment of basalt fiber: 10 g of basalt fiber was mixed with 400 ml of acetone and stirred at 500 r / min at 75℃ for 48 hours and washed, and dried at 80℃ for 24 hours; then a sodium hydroxide solution with a concentration of 2 mol / L was added, stirred at 500 r / min at 60℃ for 30 minutes, washed with deionized water until neutral, and dried at 80℃ for 12 hours; further, it was added to 5% hydrogen peroxide, stirred for 3 hours, and washed with deionized water until neutral to obtain surface-activated basalt fiber.

[0060] (2) In-situ growth of Ce particles on the surface of basalt fiber: Weigh 0.6210 g of cerium chloride and dissolve it in 40 ml of anhydrous ethanol. Then add 4.9676 g of activated basalt fiber and stir the reaction for 12 hours. Wash with deionized water and dry at 60°C to obtain basalt fiber with Ce particles assembled on the surface.

[0061] (3) Preparation of composite coating: 2.5 wt.% Ce particles / basalt fiber heterojunction was mechanically mixed with 90 wt.% SH-E50 epoxy powder to obtain component A; 7 wt.% SH-500 curing agent and 0.5 wt.% HYC-01 additive were mixed and stirred to obtain component B; then, component A and component B were ball-milled, electrostatically sprayed, and cured at 180℃ for 30 minutes to obtain the anti-corrosion coating. The erosion resistance was tested at 25℃, sand content of 20 wt.%, impact angle of 90°, impact pressure of 0.25 MPa, and test time of 25 minutes. The maximum erosion depth of the coating surface was 2.69 mm, and the coating mass loss was 1.18 g; the erosion depth diagram is shown below. Figure 5 As shown. After immersion in 3.5 wt.% NaCl for 60 days, the low-frequency impedance of the coating was 10. 5 Ω·cm 2 No obvious fluorescent effect was observed in the damaged area of ​​the coating.

[0062] Comparative Example 2 (1) Surface pretreatment of basalt fiber: 10 g of basalt fiber was mixed with 400 ml of acetone and stirred at 500 r / min at 75℃ for 48 hours and washed, and dried at 80℃ for 24 hours; then a sodium hydroxide solution with a concentration of 2 mol / L was added, stirred at 500 r / min at 60℃ for 30 minutes, washed with deionized water until neutral, and dried at 80℃ for 12 hours; further, it was added to 5% hydrogen peroxide, stirred for 3 hours, and washed with deionized water until neutral to obtain surface-activated basalt fiber.

[0063] (2) In-situ growth of Ce-MOF on the surface of basalt fiber: ① Weigh 0.6210 g of cerium chloride and dissolve it completely in 40 ml of anhydrous ethanol. Then add 4.9676 g of activated basalt fiber and stir the reaction for 12 hours. Wash with deionized water and dry at 60°C to obtain basalt fiber with Ce particles assembled on the surface. ② Weigh 0.6050 g of cysteine ​​and dissolve it in a mixed solution of 40 ml of anhydrous ethanol and 40 ml of deionized water. Adjust the pH of the solution to 9 with 2 mol / L sodium hydroxide and add it dropwise to the above solution. Stir the reaction for 12 hours and wash with deionized water. Dry at 60°C to obtain basalt fiber with Ce-MOF grown in situ on the surface.

[0064] (3) Preparation of composite coating: 2.5 wt.% of basalt fiber with in-situ Ce-MOF growth was mechanically mixed with 90 wt.% of SH-E50 epoxy powder to obtain component A; 7 wt.% of SH-500 curing agent and 0.5 wt.% of HYC-01 additive were mixed and stirred to obtain component B; then, component A and component B were ball-milled, electrostatically sprayed, and cured at 180℃ for 30 minutes to obtain the anti-corrosion coating. The erosion resistance was tested at 25℃, sand content of 20 wt.%, impact angle of 90°, impact pressure of 0.25 MPa, and test time of 25 minutes. The maximum erosion depth of the coating surface was 2.33 mm, and the coating mass loss was 1.01 g; the erosion depth diagram is shown below. Figure 6 As shown. After immersion in 3.5 wt.% NaCl for 60 days, the low-frequency impedance of the coating was 10. 6 Ω·cm 2 No obvious fluorescent effect was observed in the damaged area of ​​the coating.

[0065] Comparative Example 3 (1) Surface pretreatment of basalt fiber: 10 g of basalt fiber was mixed with 400 ml of acetone and stirred at 500 r / min at 75°C for 48 hours and washed, and then dried at 80°C for 24 hours; then a sodium hydroxide solution with a concentration of 2 mol / L was added, stirred at 500 r / min at 60°C for 30 minutes, washed with deionized water until neutral, and dried at 80°C for 24 hours; further, 5% hydrogen peroxide was added, stirred for 3 hours, and washed with deionized water until neutral to obtain surface-activated basalt fiber.

[0066] (2) In-situ growth of Ce-MOF on the surface of basalt fiber: ① Weigh 0.6210 g of cerium chloride and dissolve it completely in 40 ml of anhydrous ethanol. Then add 4.9676 g of activated basalt fiber and stir the reaction for 24 hours. Wash with deionized water and dry at 60°C to obtain basalt fiber with Ce particles assembled on the surface. ② Weigh 0.6050 g of cysteine ​​and dissolve it in a mixed solution of 40 ml of anhydrous ethanol and 40 ml of deionized water. Adjust the pH of the solution to 9 with 2 mol / L sodium hydroxide and add it dropwise to the above solution. Stir the reaction for 24 hours and wash with deionized water. Dry at 60°C to obtain basalt fiber with Ce-MOF grown in situ on the surface. ③ Dissolve 0.7948 g of isothiocyanate in 40 ml of anhydrous ethanol, and add 0.6210 g of basalt fiber with Ce-MOF grown in situ on the surface. React at 80 °C for 24 hours, wash once with deionized water by centrifugation, and dry at 60 °C to obtain basalt fiber with Ce-MOF grown in situ on the surface and loaded with isothiocyanate.

[0067] (3) Preparation of composite coating: 2 wt.% Ce-MOF / basalt fiber heterojunction was mechanically mixed with 90.5 wt.% SH-E50 epoxy powder to obtain component A; 6.5 wt.% SH-500 curing agent and 1 wt.% HYC-01 additive were mixed and stirred to obtain component B; then, component A and component B were ball-milled, electrostatically sprayed, and cured at 180℃ for 30 minutes to obtain the anti-corrosion coating. The erosion resistance was tested at 25℃, sand content of 20 wt.%, impact angle of 90°, impact pressure of 0.25 MPa, and test time of 25 minutes. The maximum erosion depth of the coating surface was 2.28 mm, and the coating mass loss was 0.96 g; the erosion depth diagram is shown below. Figure 7 As shown. After immersion in 3.5 wt.% NaCl for 60 days, the low-frequency impedance of the coating was 10. 6 Ω·cm 2 On the sixth day, the damaged area of ​​the coating exhibited a fluorescent effect, changing from yellow to yellow-green, indicating that the corrosion warning function had essentially disappeared.

[0068] Comparative Example 4 The method is the same as that of Comparative Example 2, except that the 2.5 wt.% of basalt fibers of surface in-situ grown Ce-MOF in step (3) is replaced with a mixture of isothiocyanate and basalt fibers of surface in-situ grown Ce-MOF.

[0069] The erosion resistance of the coating was tested under the following conditions: temperature 25℃, sand content 20 wt.%, impact angle 90°, impact pressure 0.25 MPa, and test time 25 minutes. The maximum erosion depth of the coating surface was 3.62 mm, and the coating mass loss was 1.89 g. After immersion in 3.5 wt.% NaCl for 60 days, the low-frequency impedance of the coating was 10 Ω·cm. 5 Ω·cm 2 On the sixth day, the damaged area of ​​the coating showed a weak fluorescent effect, and the color changed from yellow to yellow-green, indicating that the corrosion warning function had basically disappeared.

[0070] Comparative Example 5 The method is the same as that of Comparative Example 2, except that the 2.5 wt.% of basalt fibers in step (3) that are grown in situ on the surface of Ce-MOF are replaced with basalt fibers loaded only with isothiocyanate.

[0071] The erosion resistance of the coating was tested under the following conditions: temperature 25℃, sand content 20 wt.%, impact angle 90°, impact pressure 0.25 MPa, and test time 25 minutes. The maximum erosion depth of the coating surface was 4.48 mm, and the coating mass loss was 3.12 g. After immersion in 3.5 wt.% NaCl for 60 days, the low-frequency impedance of the coating was 10 Ω·cm. 4 Ω·cm 2 On the fifth day, the damaged area of ​​the coating showed a certain fluorescent effect, changing from yellow to green, indicating a weak corrosion warning function.

[0072] Comparative Example 6 (Insufficient Ce-MOF / basalt fiber heterojunction) The method is the same as in Example 1, except that the amount of Ce-MOF / basalt fiber heterojunction is 0.5wt% and the amount of epoxy powder is 92wt%.

[0073] The erosion resistance of the coating was tested under the following conditions: temperature 25℃, sand content 20 wt.%, impact angle 90°, impact pressure 0.25 MPa, and test time 25 minutes. The maximum erosion depth of the coating surface was 3.96 mm, and the coating mass loss was 2.14 g. After immersion in 3.5 wt.% NaCl for 60 days, the low-frequency impedance of the coating was 10. 6 Ω·cm 2 On the fifth day, the damaged area of ​​the coating showed a certain fluorescent effect, changing from yellow to green, indicating a weak corrosion warning function.

[0074] Comparative Example 7 (Excessive use of Ce-MOF / basalt fiber heterojunction) The method is the same as in Example 1, except that the amount of Ce-MOF / basalt fiber heterojunction is 15wt% and the amount of epoxy powder is 77.5wt%.

[0075] Characterization: Erosion resistance was tested at 25℃, with a sand content of 20 wt.%, an impact angle of 90°, an impact pressure of 0.25 MPa, and a test time of 25 minutes. The maximum erosion depth of the coating surface was 5.06 mm, and the coating mass loss was 4.22 g. After immersion in 3.5 wt.% NaCl for 60 days, the low-frequency impedance of the coating was 10 Ω·cm. 4 Ω·cm 2 On the sixth day, the damaged area of ​​the coating exhibited a fluorescent effect, changing from yellow to yellow-green, indicating that the corrosion warning function had essentially disappeared.

[0076] In addition, the applicant also conducted experiments with other raw materials, process operations, and process conditions described in this specification, referring to the aforementioned embodiments, and obtained relatively ideal results in all cases.

[0077] It should be understood that the technical solutions of the present invention are not limited to the specific embodiments described above. Any technical modifications made to the technical solutions of the present invention without departing from the spirit and scope of the claims are within the scope of protection of the present invention.

Claims

1. A method for preparing Ce-MOF / basalt fiber heterojunctions, characterized in that, include: Surface-activated basalt fibers were obtained by pretreatment of basalt fibers. Ce particles are assembled on the surface-activated basalt fibers to obtain basalt fibers with surface-assembled Ce particles. The basalt fibers with Ce particles assembled on the surface are reacted with organic ligands to obtain basalt fibers with Ce-MOF grown in situ on the surface. Furthermore, a fluorescent indicator was loaded onto the surface of Ce-MOF basalt fibers grown in situ on the surface to prepare a Ce-MOF / basalt fiber heterojunction.

2. The preparation method according to claim 1, characterized in that, Specifically, it includes: (1) Basalt fibers were pretreated with acetone, alkaline solution and hydrogen peroxide in sequence to obtain surface-activated basalt fibers; (2) Dissolve the cerium-containing metal precursor in ethanol, then add the surface-activated basalt fiber and stir at 10℃~50℃ for 6h-18h. After washing and drying, basalt fiber with Ce particles assembled on the surface is obtained. (3) Mix the organic ligand with water and ethanol and adjust the pH value to 7.5~10.

5. Then mix it with the basalt fiber with Ce particles assembled on the surface and stir at 10℃~50℃ for 6h-18h. Then wash and dry to obtain basalt fiber with Ce-MOF grown in situ on the surface. (4) Dissolve the fluorescent indicator in ethanol, add the basalt fiber with Ce-MOF grown in situ on the surface, and react at 60℃~95℃ for 6h-18h. Then wash and dry to obtain basalt fiber with Ce-MOF grown in situ on the surface and loaded with fluorescent indicator, i.e., the Ce-MOF / basalt fiber heterojunction.

3. The preparation method according to claim 2, characterized in that: The alkaline solution includes any one or more combinations of sodium hydroxide solution, potassium hydroxide solution, and ammonia solution; And / or, the cerium-containing metal precursor includes any one or more combinations of cerium chloride, cerium sulfate, and cerium nitrate; And / or, the organic ligand comprises any one or more combinations of cysteine, terephthalic acid, 2,5-furandicarboxylic acid, pyromellitic acid, and pyromellitic tetracarboxylic acid; And / or, the fluorescent indicator includes any one or more combinations of isothiocyanates, coumarins, rhodamine derivatives, and fluorescein derivatives; And / or, in step (1), the average diameter of the basalt fibers is 4-20 μm; And / or, in step (2), the mass ratio of the cerium-containing metal precursor to the surface-activated basalt fiber is 1:5 to 1:15; And / or, in step (3), the volume ratio of ethanol to water is 1:(0.1~2). And / or, in step (3), the mass ratio of the organic ligand to the basalt fiber with surface-assembled Ce particles is 1:5 to 1:15; And / or, in step (4), the mass ratio of the fluorescent indicator to the basalt fiber of Ce-MOF grown in situ on the surface is 2:1 to 1:

2.

4. The Ce-MOF / basalt fiber heterojunction prepared by the preparation method according to any one of claims 1-3, characterized in that, include: The surface-activated basalt fibers serve as a carrier, Ce-MOFs are grown in situ on the carrier surface, and a fluorescent indicator is loaded on the carrier surface.

5. A Ce-MOF / basalt fiber heterostructure modified anticorrosive coating, characterized in that, include: Component A and component B, wherein component A comprises the Ce-MOF / basalt fiber heterostructure and epoxy powder as described in claim 4; and component B comprises additives and curing agents.

6. The Ce-MOF / basalt fiber heterostructure modified anticorrosive coating according to claim 5, characterized in that: The Ce-MOF / basalt fiber heterojunction content in the Ce-MOF / basalt fiber heterojunction modified anticorrosive coating is 1~5wt%; And / or, the epoxy powder content in the Ce-MOF / basalt fiber heterostructure modified anticorrosion coating is 80~95wt%; And / or, the content of additives in the Ce-MOF / basalt fiber heterostructure modified anticorrosion coating is 0.5~1.5wt%; And / or, the content of curing agent in the Ce-MOF / basalt fiber heterostructure modified anticorrosion coating is 2~10wt%; And / or, the epoxy powder comprises any one or more combinations of bisphenol A type epoxy, phenolic epoxy, and alicyclic epoxy; And / or, the additives include any one or more combinations of leveling agents, defoamers, and adhesion promoters; And / or, the curing agent includes amine curing agents and / or phenolic curing agents.

7. A method for preparing a Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating, characterized in that, include: Provide the Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating as described in claim 5 or 6; Ce-MOF / basalt fiber heterojunctions are mechanically mixed with epoxy powder to form component A; curing agent and additives are mixed and stirred to form component B. Furthermore, the components A and B are ball-milled and mixed, applied to the surface of a metal substrate by electrostatic spraying, and cured to obtain a Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating.

8. The preparation method according to claim 7, characterized in that: The curing process is carried out at a temperature of 150℃~250℃ for a time of 0.2~1.0h. And / or, the metal substrate includes any one of carbon steel, stainless steel, aluminum alloy, copper alloy, and titanium alloy.

9. Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating prepared by the preparation method of claim 7 or 8.

10. The application of the Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating as described in claim 5 or 6, and the Ce-MOF / basalt fiber heterostructure modified anti-corrosion coating as described in claim 9, in the corrosion protection of metal equipment in marine high-salt, high-humidity, and erosion-prone multi-factor coupled environments.

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