pH-responsive mica@cerium zinc filler and visual self-warning marine anti-corrosion and anti-fouling coatings

Abstract

The present application discloses a pH-responsive mica@cerium zinc filler and a visual self-warning marine anti-corrosion and anti-fouling coating. The filler effectively induces charge separation through the construction of a heterogeneous structure, improves photocatalytic performance and photocathode protection capability, and enhances the UV resistance and anti-fouling performance of the disclosed coating. In addition, the indicator released by the filler in response to pH changes can generate a deep red metal chelate in the damaged area of ​​the substrate. This feature not only slows down the expansion of the corrosion area of ​​the substrate, but also enables the corrosion area of ​​the coating to be visually observed, and has a visual self-warning function. At the same time, the active oxygen released by the filler can inhibit the attachment of bacteria to the coating surface, effectively avoiding the damage of microorganisms to the polymer structure and the deposition of biofilms, and enhancing the overall protective performance of the coating. The disclosed coating integrates anti-corrosion, anti-fouling and self-warning functions, and is intended to provide stable and durable protection in harsh seawater environments.

Description

Technical Field

[0001] The present disclosure relates to the field of marine anti-corrosion materials, and in particular to a composite material, a coating and a preparation method for a marine anti-corrosion and anti-fouling coating. Background Art

[0002] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

[0003] To effectively protect metals from or reduce corrosion in marine environments, surface coating technology is crucial. However, traditional protective coatings often contain micro-defects and small pores during the fabrication process, compromising their integrity. Furthermore, UV radiation exacerbates polymer chain breakage, leading to material degradation and exposure of defects. Furthermore, high temperatures exacerbate polymer chain segmentation and thermal motion within the coating, creating more pores and defects, accelerating coating degradation and failure. Furthermore, in actual use, microbial attachment can lead to complex corrosion problems, further weakening the coating's protective properties. Consequently, under the combined effects of these harsh environmental conditions, corrosive media can accelerate penetration into the coating through these defects, initiating localized corrosion of the substrate. Over time, the area of ​​localized corrosion expands, causing the coating to lose its protective capabilities before reaching its intended service life. Therefore, developing intelligent protective coatings with corrosion warning capabilities, corrosion inhibition and repair capabilities, and anti-fouling adhesion capabilities is crucial, enabling timely repair before severe corrosion occurs, thereby extending the service life of the entire protective system.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may contain information that does not constitute prior art. Summary of the Invention

[0005] In view of at least one of the above technical problems, the present disclosure provides a mica@zinc oxide filler and a composite material for a visual self-warning marine anti-corrosion and anti-fouling coating to solve the problem that mica filler will produce uneven dispersion and agglomeration in the coating, thereby affecting the improvement of the anti-corrosion and anti-fouling performance of the coating.

[0006] In the first aspect, the pH-responsive mica@cerium-zinc filler comprises:

[0007] Cerium salt modified mica, zinc salt, metal developer and polycarboxyl polymer.

[0008] In the present disclosure and possible embodiments, the cerium salt is one or more of cerium chloride, cerium sulfate, cerium acetate, cerium perchlorate, or cerium nitrate;

[0009] The mica is one or more of muscovite, biotite, sericite or conductive mica, and its specification is 200-800 mesh;

[0010] The zinc salt is one or more of zinc chloride, zinc sulfate, zinc acetate or zinc nitrate;

[0011] The metal developer is o-phenanthroline and / or 5,6-diamino-1,10-o-phenanthroline;

[0012] The polycarboxyl polymer is one or more of polyacrylic acid, polylactic acid, sodium polystyrene sulfonate or polyacrylamide-2-acrylamide-2-methylpropanesulfonic acid.

[0013] In a second aspect, the preparation method of the pH-responsive mica@cerium-zinc filler according to any one of the first aspects comprises:

[0014] Preparation of cerium salt modified mica;

[0015] After dissolving the metal developer in a chlorine-containing solvent, a mixed aqueous solution of zinc salt and the cerium salt-modified mica is added, and after stirring evenly, a second alkali solution is added to form a mixed system. After the mixed system is reacted at a set temperature for a set time, a polycarboxyl polymer is added and the reaction is continued. The resulting reaction product is the pH-responsive mica@cerium-zinc filler.

[0016] In the present disclosure and possible embodiments, the method for preparing cerium salt-modified mica includes:

[0017] A first base is added to an alcohol dispersion solution of mica and cerium salt to form a reaction system, the reaction system is reacted at 150-200° C. for 10-18 hours, and the reaction product is dried and calcined to obtain the cerium salt-modified mica.

[0018] In the present disclosure and possible embodiments, the alcohol dispersion solution has an alcohol-to-water ratio of 1:4 to 5:1, and the alcohol is ethanol;

[0019] The first base is one or more of NaOH, KOH or NH4OH;

[0020] By mass, mica powder: cerium salt: ethanol: water: first base = 0.8-5.0: 0.4-4.0: 10.0-100.0: 30.0-200.0: 0.4-5.0;

[0021] The calcination temperature is 500-800°C and the calcination time is 4-8h;

[0022] The drying temperature is 80-100° C., and the drying time is 12-48 hours.

[0023] In the present disclosure and possible embodiments, a cationic surfactant is further added to the mixed system;

[0024] The reaction time at the set temperature is 1 to 3 hours at 30 to 50° C., then the temperature is raised to 50 to 65° C. and the reaction is continued for 3 to 6 hours; the polycarboxyl polymer is added and the reaction is continued at 60 to 75° C. for 1 to 4 hours.

[0025] In the present disclosure and possible embodiments, the chlorine-containing solvent is dichloromethane and / or chloroform;

[0026] The cationic surfactant is a mixture of one or more of sodium lauryl sulfate, sodium lauryl sulfonate or sodium dodecylbenzene sulfonate;

[0027] The second base is NaOH and / or KOH;

[0028] Calculated by mass, cerium salt modified mica: metal color developer: chlorine-containing solvent: cationic surfactant: zinc salt: water: second base: polycarboxyl polymer = 1.0~10.0:1.0~18.0:10.0~100.0:2.0~20.0:0.2~3.0:120.0~1000.0:1.2~18.0:0.1~2.0.

[0029] In a third aspect, the visual self-warning marine anti-corrosion and anti-fouling coating comprises:

[0030] The pH-responsive mica@cerium-zinc filler according to any one of the first aspects.

[0031] In the present disclosure and possible embodiments, the coating composition further includes:

[0032] Epoxy resin, solvent and curing agent;

[0033] The epoxy resin is E51 type and / or E44 type epoxy resin, and the curing agent is an amine curing agent;

[0034] The amine curing agent is phenalkamine and / or polyetheramine;

[0035] The solvent is a mixed solvent of a benzene solvent and an alcohol solvent, and the mass ratio of the benzene solvent to the alcohol solvent is 3:1-1:5; the benzene solvent is toluene and / or xylene; and the alcohol solvent is n-butanol and / or amyl alcohol.

[0036] In the present disclosure and possible embodiments, by mass, epoxy resin: solvent: curing agent: pH responsive mica@cerium zinc filler = 1.5-15.0: 4.0-50.0: 1.2-15.0: 0.15-2.0.

[0037] The present disclosure has the following beneficial effects:

[0038] The pH-responsive mica / cerium zinc filler and visual self-warning marine anticorrosion and antifouling coating disclosed herein, wherein the SCC@ZPhP filler effectively induces charge separation through the construction of a heterogeneous structure, thereby improving the photocatalytic performance and photocathodic protection ability, thereby greatly enhancing the UV resistance and antifouling performance of the coating; in addition, the indicator released by the SCC@ZPhP filler in response to pH changes can generate a deep red metal chelate in the damaged area of ​​the substrate. This feature not only slows down the expansion of the substrate corrosion area, but also allows the coating corrosion area to be visually observed, thereby realizing the self-warning function, which is practically The SCC@CZPhP filler is extremely convenient during work and helps to take timely maintenance measures. At the same time, the active oxygen released by the SCC@CZPhP filler can inhibit the adhesion of bacterial colonies to the coating surface, effectively preventing microbial damage to the polymer structure and the deposition of biofilm, thereby enhancing the overall protective performance of the coating. In addition, the surface modification of the SCC@CZPhP filler significantly improves its compatibility and dispersibility with the coating, thereby enhancing the interaction between the coating and the substrate. Therefore, the composite coating prepared in the present disclosure integrates anti-corrosion, anti-fouling and self-warning functions, and is designed to provide stable and durable protection in harsh seawater environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0040] Figure 1 1 is the XRD pattern of SC, SCC and pH-responsive mica / cerium zinc composite material (SCC@ZPhP) in Example 1 of the present disclosure;

[0041] Figure 2 is the Phen release kinetics of the pH-responsive mica / cerium-zinc composite material (SCC@ZPhP) of Example 1 of the present disclosure at different pH values;

[0042] Figure 3 Figure a1 is the UV-visible DRS spectra of SC, SCC and SCC@ZPhP in Example 3; Figures a2 and a3 are the VB spectrum and band structure of the SCC@ZPhP material and the corrosion potential diagram of steel in Example 3, respectively;

[0043] Figure 4 The pH-responsive mica / cerium-zinc composite material and different concentrations of Fe in Example 2 of the present disclosure are 2+ Color change diagram after ion reaction;

[0044] Figure 5Figures a1-a3 are comparisons of the impedance of the EP coating, SC coating, and SCC@ZPhP coating in Example 3 of the present disclosure after ultraviolet irradiation at different times;

[0045] Figure 6 Figures a1-a3 are respectively schematic diagrams of visual self-warning salt spray test of EP coating, SC coating, and SCC@ZPhP coating in Example 4 of the present disclosure;

[0046] Figure 7 Figures a1, b1, and c1 are SEM images of the scratched areas of the EP coating, SC coating, and SCC@ZPhP coating in Example 4 of the present disclosure, respectively; Figures a2, b2, and c2 are EDS images of the scratched areas of the EP coating, SC coating, and SCC@ZPhP coating in Example 4 of the present disclosure, respectively;

[0047] Figure 8 Figures a\b\c\d are schematic diagrams of anti-fouling tests of the coating and epoxy coating of Example 2 of the present disclosure on different bacteria and seaweed respectively. DETAILED DESCRIPTION

[0048] The present disclosure is described below based on embodiments, but it is worth noting that the present disclosure is not limited to these embodiments. In the detailed description of the present disclosure below, some specific details are described in detail. However, for the parts not described in detail, those skilled in the art can also fully understand the present disclosure.

[0049] Furthermore, those skilled in the art should understand that the drawings are only provided to illustrate the purpose, features and advantages of the present disclosure, and are not actually drawn to scale.

[0050] At the same time, unless the context clearly requires otherwise, words such as "include", "comprising" and the like throughout the specification and claims should be interpreted as inclusive rather than exclusive or exhaustive; that is, as "including but not limited to".

[0051] The following are preferred embodiments of the present disclosure.

[0052] Example 1

[0053] (1) Preparation of cerium salt modified mica SCC:

[0054] 0.8 parts by mass of mica SC and 0.4 parts by mass of Ce(NO)3·6H2O were dispersed in 40 mL of a solution (ethanol:water ratio of 1:4) and stirred thoroughly for 1 hour. Subsequently, 0.4 parts of NaOH was slowly added to the solution and stirred for another 2 hours. The mixture was then transferred to a Teflon stainless steel autoclave and reacted at 160°C for 12 hours. After cooling, the product was collected by centrifugation and dried in an 80°C oven for 12 hours. Finally, the powder was transferred to a porcelain crucible and calcined at 500°C for 8 hours to obtain cerium salt-modified mica SCC.

[0055] (2) Preparation of pH-responsive mica / cerium zinc composite material SCC@ZPhP:

[0056] First, 1.0 part of o-phenanthroline (Phen) was added to a 150 mL three-necked flask containing 6.0 parts of chloroform and 4.0 parts of dichloromethane. Subsequently, 2.0 parts of sodium dodecyl sulfate (SDS) and 60 mL of deionized water were added to the solution and mechanically stirred at 45°C for 2 hours. Then, 40 mL of deionized water containing 1.8 parts of Zn(CH3COO)2 and 1.0 part of SCC was added dropwise to the mixed solution. Stirring was continued for 1.5 hours, followed by the addition of 1.2 parts of NaOH. The mixed solution was then allowed to react at 30°C for 3 hours before being heated to 50°C and reacted for 6 hours. Subsequently, 0.1 part of polyacrylic acid (PAA) was added to the mixture and stirred at 60°C for another 4 hours. After the reaction, the mixed solution was washed with deionized water, and SCC@ZPhP particles were collected by centrifugation and dried in an oven at 80°C for 12 hours.

[0057] (3) Preparation of visual self-warning marine anti-corrosion and anti-fouling coatings:

[0058] First, Q235 carbon steel was polished with 400- and 1000-grit sandpaper, respectively, then cleaned with ethanol and dried in an oven. Next, 1.5 parts of EP and 1.2 parts of a curing agent were added to 4.0 parts of a solvent (xylene:1-butanol = 3:1) to form a uniform dispersion under ultrasound. 0.15 parts of SCC@ZPhP were then mixed with the dispersion and sonicated for 20 minutes. The mixture was then sprayed onto carbon steel at a pressure of 0.2 MPa and cured at 50°C and 80°C for 4 hours, respectively.

[0059] exist Figure 1In the XRD pattern of the SCC@ZPhP composite, the peaks at 2θ=8.6°, 20.8°, 26.6°, 36.5° and 50.1° are the special diffraction peaks of SC. New diffraction peaks were observed at 2θ=28.6°, 33.0°, 47.4° and 56.2° in the SCC curve, which are attributed to the (111), (200), (220) and (311) crystal planes of CeO2, respectively, indicating that CeO2 particles have been loaded on the SC surface. ZnO characteristic diffraction peaks at 2θ=31.7°, 34.3°, 36.2°, 62.7° and 67.7° can be observed in the XRD pattern of the SCC@ZPhP composite, further confirming the loading of the ZnO container and the synthesis of the SCC / ZnO heterostructure.

[0060] Figure 2 The pH-responsive mica / zinc cerium composite material (SCC@ZPhP) of Example 1 of the present disclosure releases Phen at different pH values. Figure 2 As can be seen, the release rate of phenic acid (Phen) is lowest in neutral solution, reaching approximately 28.9% after 48 hours of immersion, demonstrating that SCC@ZPhP effectively inhibits Phen leakage in neutral environments. At pH 10, the release rate is significantly accelerated, reaching 75.9% after 24 hours of immersion. The amount of Phen released increases with immersion time, reaching 85.0% after 48 hours. Under acidic conditions, SCC@ZPhP also exhibits high release amounts and rapid release rates. After 48 hours of immersion, the Phen release rate reaches 59.9%, double that of the release under neutral conditions. These results demonstrate that the pH-responsive nature of the SCC@ZPhP material prevents premature Phen leakage and facilitates on-demand release during actual corrosion processes.

[0061] Example 2

[0062] (1) Preparation of cerium salt modified mica:

[0063] 4.0 parts by mass of SC and 2.0 parts by mass of Ce(NO)3·6H2O were dispersed in 200 mL of a solution (ethanol:water ratio of 5:1) and stirred thoroughly for 1 hour. Subsequently, 2.4 parts of NaOH were slowly added to the solution and stirred for another 2 hours. The mixture was then transferred to a Teflon stainless steel autoclave and reacted at 160°C for 12 hours. After cooling, the product was collected by centrifugation and dried in an 80°C oven for 12 hours. Finally, the powder was transferred to a porcelain crucible and calcined at 800°C for 4 hours to obtain a cerium salt-modified mica SCC.

[0064] (2) Preparation of pH-responsive mica / cerium zinc composite material SCC@ZPhP:

[0065] First, 5.0 parts of Phen were added to a 500 mL three-necked flask containing 60 parts of chloroform and 40 parts of dichloromethane. Subsequently, 10 parts of SDS and 300 mL of deionized water were added to the solution and mechanically stirred at 45°C for 2 hours. Next, 40 mL of deionized water containing 10.0 parts of Zn(CH3COO)2 and 5.0 parts of SCC were added dropwise to the mixed solution. Stirring was continued for 1.5 hours before the addition of 8.0 parts of NaOH. After the mixture was fully reacted at 45°C for 1 hour, the temperature was raised to 65°C and the reaction continued for 3 hours. Subsequently, 0.5 parts of PAA was added to the mixture and stirring continued at 65°C for 1 hour. After the reaction, the mixed solution was washed with deionized water, and the SCC@ZPhP particles were collected by centrifugation and dried in an oven at 80°C for 12 hours.

[0066] (3) Preparation of visual self-warning marine anti-corrosion and anti-fouling coatings:

[0067] First, Q235 carbon steel was polished with 400- and 1000-grit sandpaper, respectively, then cleaned with ethanol and dried in an oven. Next, 9.0 parts of EP and 7.2 parts of a curing agent were added to 20.0 parts of a solvent (xylene:1-butanol = 1:5) to form a uniform dispersion under ultrasound. 0.75 parts of SCC@ZPhP were then mixed with the dispersion and sonicated for 20 minutes. Subsequently, the mixture was sprayed onto the carbon steel at a pressure of 0.2 MPa and cured at 60°C for 6 hours, followed by an additional 2 hours at 100°C.

[0068] Figure 4 The pH-responsive mica / cerium-zinc composite material and different concentrations of Fe in Example 2 of the present disclosure are 2+ Color change diagram after ion reaction. The initial color of the solution is milky white. 2+ With the gradual increase of concentration, the color of the mixed solution changes from light yellow to orange to dark red, indicating that [Fe(Phen)2] 2+ Formation of ligand compounds; even in the presence of low concentrations of Fe 2+ ions, the SCC@ZPhP solution also shows an obvious color change.

[0069] Figure 8Schematic diagrams of antifouling tests performed on different bacteria against the coating of Example 2 of the present disclosure and an epoxy EP coating (CG: blank control group). Graphs a and b depict bacteria, while graphs c and d depict algae. Graphs ad show that the epoxy EP coating containing bacteria (Escherichia coli and Staphylococcus aureus) and algae was placed in a light / dark environment for antifouling performance testing. After incubation, the EP coating demonstrated extremely poor antifouling effectiveness, with a large number of surviving bacterial colonies in the culture medium and on the coating surface. In contrast, the SCC / ZPhP coating exhibited significantly fewer bacterial colonies and algae in the culture medium after incubation in the light / dark environment, demonstrating excellent antifouling effectiveness.

[0070] Example 3

[0071] (1) Preparation of cerium salt modified mica:

[0072] 2.4 parts by mass of SC and 1.5 parts by mass of Ce(NO)3·6H2O were dispersed in 150 mL of a solution (ethanol:water ratio of 1:4) and stirred thoroughly for 1 hour. Subsequently, 1.4 parts of NaOH was slowly added to the solution and stirred for another 2 hours. The mixture was then transferred to a Teflon stainless steel autoclave and reacted at 160°C for 12 hours. After cooling, the product was collected by centrifugation and dried in an 80°C oven for 12 hours. Finally, the powder was transferred to a porcelain crucible and calcined at 650°C for 7 hours to obtain a cerium salt-modified mica SCC.

[0073] (2) Preparation of pH-responsive mica / cerium zinc heterogeneous composite material SCC@ZPhP:

[0074] First, 4.0 parts of Phen were added to a 500 mL three-necked flask containing 18.0 parts of chloroform and 12.0 parts of dichloromethane. Subsequently, 6 parts of SDS and 60 mL of deionized water were added to the solution and mechanically stirred at 45°C for 2 hours. Next, 60 mL of deionized water containing 7.0 parts of Zn(CH3COO)2 and 3.3 parts of SCC were added dropwise to the mixed solution. Stirring was continued for 1.5 hours, followed by the addition of 5.0 parts of NaOH. After the mixture was fully reacted at 45°C for 1 hour, the temperature was raised to 65°C and the reaction continued for 3 hours. Subsequently, 0.3 parts of PAA was added to the mixture, and stirring was continued at 65°C for 1 hour. After the reaction, the mixed solution was washed with deionized water, and the SCC@ZPhP particles were collected by centrifugation and dried in an oven at 80°C for 12 hours.

[0075] (3) Preparation of visual self-warning marine anti-corrosion and anti-fouling coatings:

[0076] First, Q235 carbon steel was polished with 400- and 1000-grit sandpaper, respectively, then cleaned with ethanol and dried in an oven. Next, 3.0 parts of EP and 4.2 parts of a curing agent were added to 7.0 parts of a solvent (xylene:1-butanol = 5:2) to form a uniform dispersion under ultrasound. 0.42 parts of SCC@ZPhP were then mixed with the dispersion and sonicated for 20 minutes. The mixture was then sprayed onto the carbon steel at a pressure of 0.2 MPa and cured at 60°C and 80°C for 6 hours.

[0077] Table 1 shows the Eg values ​​of SC / ZPhP and SCC / ZPhP in Example 3:

[0078] Table 1 Eg values ​​of SC / ZPhP and SCC / ZPhP

[0079]

[0080] Figure 3 is the UV-visible DRS spectra (a1) of SC, SCC and SCC@ZPhP in Example 3 and V B Spectrum (a2), band structure, and steel corrosion potential diagram (a3). Figures a1-a3 show that SC has low absorption in the ultraviolet region due to its strong extinction shielding effect. SC / ZPhP, on the other hand, exhibits good absorption only in the ultraviolet region, allowing electron transitions and failing to fully improve the system's light utilization efficiency. In contrast, the heterostructure formed by SC / ZPhP and CeO2 exhibits stronger absorption of UVA and UVB. Furthermore, the red shift in the absorption band improves the light absorption range of SCC@ZPhP, enhancing the material's light capture capability over a wider wavelength range.

[0081] At the same time, - / h + The effective spatial separation and narrower Eg make SCC@ZPhP more active in the UV / visible region (Table 1), which is beneficial to produce more e - / h + , thereby improving the light utilization and conversion performance of the system.

[0082] Depend on Figure 5 As shown in a1-a3, due to the existence of internal defects in the EP coating, the poor compatibility of mica powder (SC) with the resin, and the lack of functional corrosion inhibition performance, a large amount of corrosion products are produced on the substrate surface after long-term UV exposure. On the contrary, the surface of the visual self-warning marine anti-corrosion and anti-fouling coating (SCC@ZPhP) is intact after long-term light exposure, with no obvious pitting and corrosion, and the coating impedance value can still reach 10 11 Ω·cm 2, indicating that the overall anti-corrosion performance of the coating has been significantly improved.

[0083] Example 4

[0084] (1) Preparation of cerium salt modified mica:

[0085] 5.0 parts by mass of SC and 4.0 parts by mass of Ce(NO)3·6H2O were dispersed in 300 mL of a solution (ethanol:water ratio of 1:4) and stirred thoroughly for 1 hour. Subsequently, 5.0 parts of NaOH were slowly added to the solution and stirred for another 2 hours. The mixture was then transferred to a Teflon stainless steel autoclave and reacted at 160°C for 12 hours. After cooling, the product was collected by centrifugation and dried in an 80°C oven for 12 hours. Finally, the powder was transferred to a porcelain crucible and calcined at 550°C for 7 hours to obtain a cerium salt-modified mica SCC.

[0086] (2) Preparation of pH-responsive mica / cerium zinc heterogeneous composite material SCC@ZPhP:

[0087] First, 18 parts of Phen were added to a 500 mL three-necked flask containing 60 parts of chloroform and 40 parts of dichloromethane. Subsequently, 30 parts of SDS and 100 mL of deionized water were added to the solution and mechanically stirred at 45°C for 2 hours. Next, 100 mL of deionized water containing 20 parts of Zn(CH3COO)2 and 10 parts of SCC were added dropwise to the mixed solution. Stirring was continued for 1.5 hours, followed by the addition of 18 parts of NaOH. The mixed solution was then allowed to react at 45°C for 1 hour before being heated to 65°C and reacted for 3 hours. Subsequently, 2 parts of PAA were added to the mixture and stirred at 65°C for another hour. The resulting mixture was washed with deionized water, and SCC@ZPhP particles were collected by centrifugation and dried in an oven at 80°C for 12 hours.

[0088] (3) Preparation of visual self-warning marine anti-corrosion and anti-fouling coatings:

[0089] First, Q235 carbon steel was polished with 400- and 1000-grit sandpaper, respectively, then cleaned with ethanol and dried in an oven. Next, 15.0 parts of EP and 15.0 parts of a curing agent were added to 50.0 parts of a solvent (xylene:1-butanol = 1:4) to form a uniform dispersion under ultrasound. 2.0 parts of SCC@ZPhP were then mixed with the dispersion and sonicated for 20 minutes. The mixture was then sprayed onto carbon steel at a pressure of 0.2 MPa and cured at 60°C and 90°C for 8 hours.

[0090] Depend on Figure 6As shown in Figures a1-a3, after long-term exposure to a salt spray environment, the scratched areas of EP and SC coatings accumulate a large amount of corrosion products due to the lack of functional protection, and their undamaged areas also show obvious pitting. In contrast, SCC@ZPhP exhibits relatively few corrosion products and no obvious diffusion zone. Furthermore, the deep red marks formed around the scratched areas of the coating indicate the release of the indicator, and the resulting composite deposited protective film further mitigates the erosion of the corrosive medium. At the same time, the interaction between SCC@ZPhP and the substrate not only improves the shielding and barrier properties of the coating but also reduces the generation of internal defects in the system, ensuring that the coating maintains excellent stability and long-term corrosion resistance. The formation of the deep red marks provides an intuitive early warning function for localized corrosion of the substrate, facilitating the timely identification of potential locations of substrate damage and maintenance.

[0091] from Figure 7 As can be seen from a1-a2 in the figure, the EP scratch region is dotted with a large number of loose corrosion products containing Fe and O, indicating that the substrate has been severely corroded. For SC, numerous corrosion products also form in the substrate scratch region (b1-b2). In contrast, the SCC@ZPhP scratch region produces a relatively dense barrier film that inhibits the penetration of the corrosive medium (c1). Furthermore, the presence of C, O, N, Ce, and Zn in the SCC@ZPhP scratch region further indicates the release of phen and the formation of a Ce / Zn-containing protective film (c2).

[0092] The above-described embodiments are merely examples of implementation methods of the present disclosure, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art may make various modifications, equivalent substitutions, and improvements without departing from the scope of the present disclosure, and these modifications are all within the scope of protection of the present disclosure. Therefore, the scope of protection of the present invention shall be based on the appended claims.

Claims

1. A pH-responsive mica@cerium-zinc filler, characterized in that: Its composition includes: Cerium salt modified mica, zinc salt, metal developer and polycarboxyl polymer; The cerium salt is one or more of cerium chloride, cerium sulfate, cerium acetate, cerium perchlorate or cerium nitrate; The mica is one or more of muscovite, biotite, sericite or conductive mica, and its specification is 200-800 mesh; The zinc salt is one or more of zinc chloride, zinc sulfate, zinc acetate or zinc nitrate; The metal developer is o-phenanthroline and / or 5,6-diamino-1,10-o-phenanthroline; The polycarboxyl polymer is one or more of polyacrylic acid, polylactic acid, sodium polystyrene sulfonate or polyacrylamide-2-acrylamide-2-methylpropane sulfonic acid; The preparation method thereof comprises: Preparation of cerium salt modified mica; After the metal developer is dissolved in a chlorine-containing solvent, zinc salt and the cerium salt modified cloud are added. The mixed aqueous solution of the mother is stirred evenly and then a second alkali solution is added to form a mixed system, the mixed system is reacted at a set temperature for a set time, and then a polycarboxyl polymer is added and the reaction is continued to obtain the reaction product, which is the pH-responsive mica@cerium-zinc filler; The method for preparing cerium salt modified mica comprises: The first base is added to the alcohol dispersion solution of mica and cerium salt to form a reaction system. The reaction system is reacted at 150-200° C. for 10-18 hours, and the reaction product is dried and calcined to obtain the cerium salt-modified mica.

2. The pH-responsive mica@cerium-zinc filler according to claim 1, characterized in that: The alcohol-water ratio of the alcohol dispersion solution is 1:4-5:1, and the alcohol is ethanol; The first base is one or more of NaOH, KOH or NH4OH; By mass, mica powder: cerium salt: ethanol: water: first alkali = 0.8~5.0: 0.4~4.0: 10.0~100.0: 30.0~200.0: 0.4~5.0; The calcination temperature is 500-800°C and the calcination time is 4-8 hours; The drying temperature is 80-100°C, and the drying time is 12-48 hours.

3. The pH-responsive mica@cerium-zinc filler according to claim 2, characterized in that: A cationic surfactant is also added to the mixed system; The set reaction time at the set temperature is 1-3 hours at 30-50°C, then the temperature is raised to 50-65°C and the reaction is continued for 3-6 hours; the adding of the polycarboxyl polymer and the continued reaction is 1-4 hours at 60-75°C.

4. The pH-responsive mica@cerium-zinc filler according to claim 3, characterized in that: The chlorinated solvent is dichloromethane and / or chloroform; The cationic surfactant is sodium lauryl sulfate, sodium lauryl sulfonate or A mixture of one or more of sodium dodecylbenzenesulfonate; The second base is NaOH and / or KOH; By mass, cerium salt modified mica: metal color developer: chlorine-containing solvent: cationic surface Surfactant: zinc salt: water: second base: polycarboxyl polymer = 1.0 ~ 10.0: 1.0 ~ 18.0: 10.0 ~ 100.0: 2.0 ~ 20.0: 0.2 ~ 3.0: 120.0 ~ 1000.0: 1.2 ~ 18.0: 0.1 ~2.

0.

5. A visual self-warning marine anti-corrosion and anti-fouling coating, characterized in that: Its composition include: The pH-responsive mica@cerium-zinc filler according to any one of claims 1 to 4.

6. The visual self-warning marine anti-corrosion and anti-fouling coating according to claim 5 is characterized in that: The composition also includes: Epoxy resin, solvent and curing agent; The epoxy resin is E51 type and / or E44 type epoxy resin, and the curing agent is an amine curing agent; The amine curing agent is phenalkamine and / or polyetheramine; The solvent is a mixed solvent of a benzene solvent and an alcohol solvent, and the mass ratio of the benzene solvent to the alcohol solvent is 3:1-1:5; the benzene solvent is toluene and / or xylene; and the alcohol solvent is n-butanol and / or amyl alcohol.

7. The visual self-warning marine anti-corrosion and anti-fouling coating according to claim 6 is characterized by: By mass, epoxy resin: solvent: curing agent: pH responsive mica@cerium zinc filler = 1.5 ~ 15.0: 4.0 ~ 50.0: 1.2 ~ 15.0: 0.15 ~ 2.0.

Images