Corrosion-resistant modified waterborne epoxy resin coating prepared from mxene-ni@c-odd and application thereof

Abstract

The application belongs to the technical field of metal substrate surface coating protection, and discloses a MXene-Ni@C-ODD, a corrosion-resistant modified water-based epoxy resin coating prepared by the MXene-Ni@C-ODD and application, wherein the MXene-Ni@C-ODD is abbreviated as mMO, a nickel source and an organic ligand are mixed and then dissolved in a solvent, a MXene suspension is added, and the mixture is hydrothermally treated at 80-180 DEG C to obtain MOFs-MXene, the MOFs-MXene is annealed at 200-800 DEG C to obtain MXene-Ni@C, and then a heptadecenyl amine ethyl imidazoline quaternary ammonium salt (ODD) solution is added, and the mixture is precipitated and dried to obtain the MXene-Ni@C-ODD. The MXene-Ni@C-ODD with magnetism is added into a water-based epoxy resin, and a modified water-based epoxy resin coating is prepared on the surface of a metal substrate by magnetic regulation and curing, and the modified water-based epoxy resin coating has physical shielding, self-healing and corrosion resistance, and can be widely applied in the field of metal surface protection.

Description

Technical Field

[0001] This invention belongs to the field of metal substrate surface coating protection technology, specifically, it relates to an MXene-Ni@C-ODD and its prepared corrosion-resistant modified waterborne epoxy resin coating and its application. Background Technology

[0002] Steel, due to its excellent mechanical properties and good plasticity, is widely used in construction, machinery manufacturing, and other fields. However, due to corrosive media in the environment, steel is highly susceptible to corrosion, leading to functional failure, shortened service life, significant economic losses, and substantial safety issues. Therefore, research has shown that coating the material surface with organic coatings is an effective corrosion protection strategy. Organic coatings are protective coatings with specific functions applied to the surface of a substrate material, offering advantages such as corrosion resistance, wear resistance, friction reduction, and heat resistance.

[0003] Organic coatings can isolate materials from corrosive media in the environment, preventing electrochemical corrosion. Waterborne epoxy resin coatings, in particular, are widely used in construction, food processing equipment, electronic and electrical equipment, and medical devices due to their environmental friendliness, ease of application, and strong adhesion. However, compared to oil-based and waterborne epoxy resin coatings, waterborne epoxy resin coatings suffer from lower durability, poorer mechanical properties, and a tendency to crack during curing, significantly shortening the material's lifespan in corrosive environments. Past improvement strategies have included adding sacrificial anode materials, corrosion inhibitors, shape memory polymers, or two-dimensional materials to protect the substrate. These two-dimensional materials provide strong physical shielding during corrosion, but often the filled two-dimensional materials tend to agglomerate in the coating, or their orientation is not entirely parallel to the substrate, hindering their full physical shielding effect. Furthermore, they suffer from poor self-healing ability after cracking, making them ineffective in protecting the substrate. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide an MXene-Ni@C-ODD; the MXene-Ni@C-ODD is paramagnetic.

[0005] Another objective of this invention is to provide a corrosion-resistant modified waterborne epoxy resin coating prepared by the above-mentioned MXene-Ni@C-ODD and its preparation method. The modified waterborne epoxy resin coating is prepared by combining specially treated magnetic MXene-Ni@C-ODD with waterborne epoxy resin on the substrate surface. It is not easy to crack, has a good physical shielding effect in corrosive environments, and releases corrosion inhibitors when the waterborne epoxy resin coating cracks, giving the waterborne epoxy resin coating strong self-healing ability and corrosion resistance.

[0006] Another objective of this invention is to provide applications of the aforementioned MXene-Ni@C-ODD.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] An MXene-Ni@C-ODD, abbreviated as mMO, is prepared by dissolving a nickel source and an organic ligand in a solvent, adding an MXene suspension, hydrothermally treating the solution at 80–180°C, collecting and drying the precipitate to obtain MOFs-MXene, annealing the MXene-Ni@C at 200–800°C, adding the MXene-Ni@C to a corrosion inhibitor solution of heptadecanylamine ethyl imidazoline quaternary ammonium salt, loading the corrosion inhibitor onto the MXene-Ni@C, collecting and drying the precipitate.

[0009] Preferably, the nickel source is NiCl2·6H2O, Ni(NO3)2·6H2O, NiSO4·6H2O, or Ni(OAc)2·4H2O; the organic ligand is 2,3,6,7,10,11-hexahydroxytriphenylene hydrate, o-benzoic acid, p-benzoic acid, 1,3,5-triphenylcarboxylic acid, or TDC (thiophene-2,5-dicarboxylic acid) pyromellitic acid; and the solvent is DMF, water, or ethanol.

[0010] Preferably, the mass ratio of the nickel source, organic ligand, and solvent is (1-10):(1-10):(1-10); the mass ratio of MXene to MOFs in MOFs-MXene is (1-10):(1-10); and the mass ratio of MXene-Ni@C to heptadecanylaminoethylimidazoline quaternary ammonium salt in the solution is (1-10):1.

[0011] Preferably, the MXene is Ti3C2T. x Ta4C3T x TiN3T x V2CT x Nb2CT x Ti3CNT x x represents the total number of functional groups on the material surface, x = 1 to 3; the concentration of the MXene suspension is 0.1 to 10 mg / mL; the concentration of the heptadecenylamine ethyl imidazoline quaternary ammonium salt corrosion inhibitor solution is 1 to 100 wt.%.

[0012] A corrosion-resistant modified waterborne epoxy resin coating is prepared using the aforementioned MXene-Ni@C-ODD.

[0013] The method for preparing the corrosion-resistant modified waterborne epoxy resin coating includes the following steps;

[0014] S1. Remove oil stains from the metal substrate with acetone or anhydrous ethanol, and polish the substrate with sandpaper to increase the surface roughness of the metal substrate;

[0015] S2. Add MXene-Ni@C-ODD and waterborne epoxy curing agent to waterborne epoxy resin and stir to obtain MXene-Ni@C-ODD waterborne epoxy resin coating, abbreviated as MO coating;

[0016] S3. When using a coating machine to apply the MO coating, magnetic control is applied to make MXene-Ni@C-ODD adhere to the waterborne epoxy resin coating. After curing at room temperature, a modified waterborne epoxy resin coating, abbreviated as mMO coating, is obtained on the surface of the metal substrate.

[0017] Preferably, the metal matrix in step S1 is stainless steel, aluminum alloy, magnesium alloy, titanium alloy or copper alloy.

[0018] Preferably, in step S2, the amount of MXene-Ni@C-ODD added is 0.001 to 20 wt.% of the waterborne epoxy resin; the waterborne epoxy resin is epoxy resin F0716, epoxy resin H1150, or epoxy resin H145, the waterborne epoxy curing agent is F0716, H205B, or H206B, and the mass ratio of the waterborne epoxy resin to the waterborne epoxy curing agent is (1 to 10):1.

[0019] Preferably, the thickness of the mAMO ​​coating in step S3 is 10–100 μm.

[0020] The application of MXene-Ni@C-ODD in the field of metal surface protection.

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

[0022] 1. The MOFs of this invention are formed by the coordination assembly of nickel ions and organic ligands. During hydrothermal treatment, MOFs are simultaneously formed and assembled on MXene. After annealing, MXene-Ni@C is formed. MXene-Ni@C is magnetic and can support the corrosion inhibitor ODD, forming an MXene-Ni@C-ODD waterborne epoxy resin coating. Further conditioning yields a modified waterborne epoxy resin coating. Due to the strong adhesion of waterborne epoxy resin, this modified waterborne epoxy resin coating can bond firmly to the metal substrate and is not easily detached. Adding MXene-Ni@C-ODD to waterborne epoxy resin coatings imparts stronger corrosion inhibition. Combined with magnetic field-controlled scraping, this modified waterborne epoxy resin coating exhibits physical shielding, self-healing properties, and corrosion resistance, solving the problem of easy cracking during the curing process. It prevents water and corrosive substances from contacting the substrate through micropores formed during curing, thus avoiding corrosion. Simultaneously, ultrasonic treatment of MXene-Ni@C-ODD ensures more uniform dispersion within the waterborne epoxy resin coating, resulting in excellent corrosion protection. The magnetically controlled modified waterborne epoxy resin coating exhibits superior healing performance, with a corrosion current reaching 5.2 × 10⁻⁶. -13 A·cm -2 above.

[0023] 2. This invention incorporates a hydrophilic heptadecanylamine ethyl imidazoline quaternary ammonium salt suspension as a corrosion inhibitor into the waterborne epoxy resin coating, thereby protecting the coating. When defects develop in the waterborne epoxy resin coating due to changes in the external environment, the corrosion inhibitor functions, forming a precipitation layer and an adsorption layer on the metal substrate surface. This endows the waterborne epoxy resin coating with self-healing capabilities, improves its corrosion resistance, and extends the service life of the substrate.

[0024] 3. This invention uses magnetic modulation to modify the waterborne epoxy resin coating of MXene-Ni@C-ODD, which solves the problem of the disordered distribution of MXene in MXene-Ni@C-ODD in the waterborne epoxy resin coating. This allows the MXene in MXene-Ni@C-ODD to be arranged parallel to the metal substrate, exerting its physical shielding effect and improving the corrosion resistance of the waterborne epoxy resin coating. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the scanning electron microscope morphology of MXene and MXene-Ni@C-ODD in Example 1.

[0026] Figure 2 This is a schematic diagram of the paramagnetism of MXene and MXene-Ni@C-ODD under a magnet in Example 1.

[0027] Figure 3The macroscopic morphology of the surface of the waterborne epoxy resin coating MXene-Ni@C-ODD prepared in Example 1 is shown.

[0028] Figure 4 Impedance spectra of the waterborne epoxy resin coating, MXene-Ni@C-ODD waterborne epoxy resin coating (MO coating), and modified waterborne epoxy resin coating (mMO coating) of Example 1.

[0029] Figure 5 The Tafel test curves after scratching the coatings are shown for the waterborne epoxy resin coatings of Example 1, namely the MXene-Ni@C-ODD waterborne epoxy resin coating (MO coating) and the modified waterborne epoxy resin coating (mMO coating). Detailed Implementation

[0030] The present invention will be further described in detail below with reference to embodiments, but the embodiments of the present invention are not limited thereto. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in this technical field.

[0031] In this embodiment of the invention, waterborne epoxy resin F0716 and curing agent F0716 were purchased from Shenzhen Yoshida Chemical Co., Ltd.; waterborne epoxy resin H1150 and curing agent H205B were purchased from Shanghai Hanzhong Chemical Co., Ltd.; and waterborne epoxy resin H145 and curing agent H206B were purchased from Shanghai Hanzhong Coatings Co., Ltd.

[0032] Example 1

[0033] 1. Pre-treat the Q235 metal substrate by removing oil stains with acetone or anhydrous ethanol and sanding the substrate with sandpaper to increase the surface roughness of the substrate, so as to facilitate the adhesion of water-based epoxy resin to the substrate.

[0034] 2. Mix NiCl2·6H2O (mass ratio 10:7) and the organic ligand 2,3,6,7,10,11-hexahydroxytriphenylene hydrate (HHTP), then add the mixture to DMF and sonicate at 11–20 W / L. Next, add 40 mL of 0.5 mg / mL ultrasonically dispersed MXene (Ti3C2T). x x is the total number of functional groups on the surface of the material (x = 1 to 3). The suspension is hydrothermally treated at 80℃ for 10 h, the precipitate is dried and collected to prepare MOFs-MXene. After annealing at 700℃, MXene-Ni@C is obtained. Then, it is added to a 70 wt.% solution of hydrophilic heptadecenylamine ethyl imidazoline quaternary ammonium salt (ODD) as a corrosion inhibitor. The corrosion inhibitor ODD is loaded onto MXene-Ni@C, the precipitate is collected and dried to obtain MXene-Ni@C-ODD, abbreviated as mMO.

[0035] 3. Add 1 wt.% of MXene-Ni@C-ODD to waterborne epoxy resin F0716, then add waterborne epoxy curing agent F0716 and mix. This will produce an MXene-Ni@C-ODD waterborne epoxy resin coating, abbreviated as MO coating. The mass ratio of waterborne epoxy resin F0716 to waterborne epoxy curing agent F0716 is 3:1.

[0036] 4. When using a coating machine for scraping, magnetic control is applied. Two magnets are placed at the front end of the coating machine. Like magnetic poles attract each other. As the machine moves forward, the magnetic MXene-Ni@C-ODD tends to align in parallel due to the magnetic field, reducing forward resistance. During the process, the magnetic field gradually weakens, and eventually the MXene-Ni@C-ODD adheres to the waterborne epoxy resin coating. After curing at room temperature, a modified waterborne epoxy resin coating, abbreviated as mMO coating, is obtained on the surface of the Q235 metal substrate.

[0037] Figure 1 These are scanning electron microscope (SEM) images of MXene and MXene-Ni@C-ODD from Example 1. From... Figure 1 As can be seen from the image, the spherical particles on MXene are Ni@C, and the white deposits are the ODD corrosion inhibitors loaded on Ni@C, indicating that MXene-Ni@C-ODD was successfully prepared. Figure 2 This is a schematic diagram illustrating the paramagnetism of MXene and MXene-Ni@C-ODD under a magnet in Example 1. MXene and MXene-Ni@C-ODD were placed in two separate bottles, and a magnet was placed close between the two bottles. Figure 2 It can be observed that MXene remains at the bottom of the bottle, while MXene-Ni@C-ODD is adsorbed onto the bottle wall near the magnet, indicating that the prepared MXene-Ni@C-ODD is paramagnetic. Figure 3 The morphology of the surface of the waterborne epoxy resin coating MXene-Ni@C-ODD prepared in Example 1 is shown below. Figure 3 It can be seen that the prepared waterborne epoxy resin coating of MXene-Ni@C-ODD has a uniform color distribution and no small black spots formed by the segregation of MXene-Ni@C-ODD appear, indicating that MXene-Ni@C-ODD can be uniformly dispersed in waterborne epoxy resin. Figure 4 The images show the impedance spectra of the waterborne epoxy resin coating, the MXene-Ni@C-ODD waterborne epoxy resin coating, and the modified waterborne epoxy resin coating in Example 1. From... Figure 4It can be seen that the addition of MXene-Ni@C-ODD can reduce the corrosion rate of the metal matrix Q235 by anions in a 3.5 wt.% NaCl solution, and the impedance arc increases to 3.48 × 10⁻⁶ after magnetic field modulation. 6 Ω·cm -2 This demonstrates that magnetic field modulation can adjust the MXene in MXene-Ni@C-ODD to be arranged parallel to the matrix, thus better exerting its physical shielding effect. Figure 5 Tafel test curves after scratching the waterborne epoxy resin coatings of Example 1, specifically the MXene-Ni@C-ODD waterborne epoxy resin coating (MO coating) and the modified waterborne epoxy resin coating (mMO coating). Figure 5 As can be seen from the Tafel test after the coating was scratched, the water-based epoxy resin coating lost its organic passive protection ability and its anti-corrosion protection failed after being damaged. The coating with MXene-Ni@C-ODD added was able to successfully repair the coating, with a corrosion current of 8.2×10. -12 A·cm -2 To maintain its cathodic protection effect, the modified waterborne epoxy resin coating under magnetic field control exhibits even better healing performance, with a corrosion current reaching 5.2 × 10⁻⁶. -13 A·cm -2 .

[0038] Example 2

[0039] 1. Pre-treat the metal substrate AZ31 by removing oil stains from the substrate AZ31 with acetone or anhydrous ethanol, and sand the substrate with sandpaper to increase the surface roughness of the substrate, so as to facilitate the adhesion of water-based epoxy resin to the substrate.

[0040] 2. Mix NiSO4·6H2O and the organic ligand p-benzoic acid in a mass ratio of 10:7, then add the mixture to DMF and sonicate at a power of 11-20 W / L. Next, add 50 mL of 0.5 mg / mL ultrasonically dispersed MXene (Ta4C3T). x (x is the total number of functional groups on the surface of the material, x = 1 to 3) The suspension was hydrothermally treated at 120℃ for 10 h, the precipitate was dried, and MOFs-MXene was prepared. After annealing at 800℃, MXene-Ni@C was obtained. Then, it was added to a 70 wt.% solution of hydrophilic heptadecenylamine ethyl imidazoline quaternary ammonium salt (ODD) as a corrosion inhibitor, and the corrosion inhibitor ODD was loaded onto MXene-Ni@C. The precipitate was collected and dried to obtain MXene-Ni@C-ODD, abbreviated as mMO.

[0041] 3. Add 1 wt.% of MXene-Ni@C-ODD to waterborne epoxy resin H1150, then add waterborne epoxy curing agent H205B and mix to obtain an MXene-Ni@C-ODD waterborne epoxy resin coating, abbreviated as MO coating. The mass ratio of waterborne epoxy resin H1150 to waterborne epoxy curing agent H205B is 4:1.

[0042] 4. When using a coating machine for scraping, magnetic control is applied. Two magnets are placed at the front end of the coating machine. Like magnetic poles attract each other. As the machine moves forward, the magnetic MXene-Ni@C-ODD tends to align in parallel due to the magnetic field, reducing resistance. As the machine moves forward, the magnetic field gradually weakens, and eventually the MXene-Ni@C-ODD adheres to the waterborne epoxy coating. After curing at room temperature, a modified waterborne epoxy resin coating, abbreviated as mMO coating, is obtained on the substrate surface.

[0043] In this embodiment, MXene-Ni@C-ODD exhibits paramagnetism, and the resulting modified waterborne epoxy resin coating shows uniform color distribution without the appearance of small black spots caused by MXene-Ni@C-ODD segregation, indicating that MXene-Ni@C-ODD can be uniformly dispersed in the waterborne epoxy resin. Electrochemical testing results show that the addition of MXene-Ni@C-ODD reduces the corrosion rate, and the impedance arc increases to 2.99 × 10⁻⁶ after magnetic field modulation. 6 Ω·cm -2 This demonstrates that magnetic field modulation can adjust the MXene arrangement in MXene-Ni@C-ODD to be parallel to the substrate, thus better exerting its physical shielding effect. Tafel testing results after scratching the coating show that the waterborne epoxy resin coating loses its organic passive protection capability and its corrosion protection fails after damage. The waterborne epoxy resin coating with added MXene-Ni@C-ODD can successfully repair the coating and maintain its cathodic protection function (corrosion current 8.8 × 10⁻⁶). -12 A·cm -2 The modified waterborne epoxy resin coating, after being regulated by a magnetic field, exhibits even better healing performance, with a corrosion current reaching 6.2 × 10⁻⁶. -13 A·cm -2 .

[0044] Example 3

[0045] 1. Pre-treat the metal substrate ZL101 by removing oil stains from the substrate ZL101 with acetone or anhydrous ethanol, and sand the substrate with sandpaper to increase the surface roughness of the substrate, so as to facilitate the adhesion of water-based epoxy resin to the substrate.

[0046] 2. Mix Ni(OAc)₂·6H₂O and the organic ligand 1,3,5-benzenetricarboxylic acid in a 1:1 mass ratio, add the mixture to DMF, and sonicate at 11–20 W / L. Then add 50 mL of 0.5 mg / mL ultrasonically dispersed MXene (TiN₃T) x (x is the total number of functional groups on the surface of the material, x = 1 to 3) The suspension was hydrothermally treated at 180℃ for 10 h, the precipitate was collected and dried to prepare MOFs-MXene, and after annealing at 800℃, MXene-Ni@C was obtained. Then, it was added to a 70 wt.% solution of hydrophilic heptadecenylamine ethyl imidazoline quaternary ammonium salt (ODD) as a corrosion inhibitor, and the corrosion inhibitor ODD was loaded onto MXene-Ni@C. The precipitate was collected and dried to obtain MXene-Ni@C-ODD, abbreviated as mMO.

[0047] 3. Add 2 wt.% of MXene-Ni@C-ODD to waterborne epoxy resin H145, then add waterborne epoxy curing agent H206B and mix to obtain an MXene-Ni@C-ODD waterborne epoxy resin coating, abbreviated as MO coating. The mass ratio of waterborne epoxy resin H145 to waterborne epoxy curing agent H206B is 2:1.

[0048] 4. When using a coating machine for scraping, magnetic control is applied. Two magnets are placed at the front end of the coating machine. Like magnetic poles attract each other. As the machine moves forward, the magnetic MXene-Ni@C-ODD tends to align in parallel due to the magnetic field, reducing resistance. As the machine moves forward, the magnetic field gradually weakens, and eventually the MXene-Ni@C-ODD adheres to the waterborne epoxy coating. After curing at room temperature, a modified waterborne epoxy resin coating, abbreviated as mMO coating, is obtained on the substrate surface.

[0049] In this embodiment, MXene-Ni@C-ODD exhibits paramagnetism, and the resulting modified waterborne epoxy resin coating shows uniform color distribution without the appearance of small black spots caused by MXene-Ni@C-ODD segregation, indicating that MXene-Ni@C-ODD can be uniformly dispersed in the waterborne epoxy resin. Electrochemical testing results show that the addition of MXene-Ni@C-ODD reduces the corrosion rate, and the impedance arc increases to 3.11 × 10⁻⁶ after magnetic field modulation. 6 Ω·cm -2This demonstrates that magnetic field modulation can adjust the MXene arrangement in MXene-Ni@C-ODD to be parallel to the substrate, thus better exerting its physical shielding effect. Tafel testing results after scratching the coating show that the waterborne epoxy resin coating loses its organic passive protection capability and its corrosion protection fails after damage. The waterborne epoxy resin coating with added MXene-Ni@C-ODD can successfully repair the coating and maintain its cathodic protection function (corrosion current 7.8 × 10⁻⁶). -12 A·cm -2 The modified waterborne epoxy resin coating, after being regulated by a magnetic field, exhibits even better healing performance, with a corrosion current reaching 6.6 × 10⁻⁶. -13 A·cm -2 .

[0050] Example 4

[0051] 1. Pre-treat the 304 metal substrate by removing oil stains from the 304 substrate with acetone or anhydrous ethanol, and sanding the substrate with sandpaper to increase the surface roughness of the substrate, so as to facilitate the adhesion of water-based epoxy resin to the substrate.

[0052] 2. Mix Ni(OAc)₂·6H₂O and the organic ligand 1,3,5-benzenetricarboxylic acid in a 1:1 mass ratio, add the mixture to DMF, and sonicate at 11–20 W / L. Then add 50 mL of 0.5 mg / mL ultrasonically dispersed MXene (V₂CT). x (x is the total number of functional groups on the surface of the material, x = 1 to 3) The suspension was hydrothermally treated at 180℃ for 10 h, the precipitate was collected and dried to prepare MOFs-MXene, and after annealing at 800℃, MXene-Ni@C was obtained. Then, it was added to a 70 wt.% solution of hydrophilic heptadecenylamine ethyl imidazoline quaternary ammonium salt (ODD) corrosion inhibitor to load the corrosion inhibitor ODD on MXene-Ni@C, the precipitate was collected and dried to obtain MXene-Ni@C-ODD, abbreviated as mMO.

[0053] 3. Add 1 wt.% of MXene-Ni@C-ODD to waterborne epoxy resin F0716, then add waterborne epoxy curing agent F0716 and mix. This will produce an MXene-Ni@C-ODD waterborne epoxy resin coating, abbreviated as MO coating. The mass ratio of waterborne epoxy resin F0716 to waterborne epoxy curing agent F0716 is 3:1.

[0054] 4. When using a coating machine for scraping, magnetic control is applied. Two magnets are placed at the front end of the coating machine. Like magnetic poles attract each other. As the machine advances, the magnetic MXene-Ni@C-ODD tends to align in parallel due to the magnetic field, reducing resistance. As the machine moves forward, the magnetic field gradually weakens, and eventually the MXene-Ni@C-ODD adheres to the waterborne epoxy coating. After curing at room temperature, a modified waterborne epoxy resin coating, abbreviated as mMO coating, is obtained on the substrate surface.

[0055] In this embodiment, MXene-Ni@C-ODD exhibits paramagnetism, and the resulting modified waterborne epoxy resin coating shows uniform color distribution without the appearance of small black spots caused by MXene-Ni@C-ODD segregation, indicating that MXene-Ni@C-ODD can be uniformly dispersed in the waterborne epoxy resin. Electrochemical testing results show that the addition of MXene-Ni@C-ODD reduces the corrosion rate, and the impedance arc increases to 2.99 × 10⁻⁶ after magnetic field modulation. 6 Ω·cm -2 This demonstrates that magnetic field modulation can adjust the MXene arrangement in MXene-Ni@C-ODD to be parallel to the substrate, thus better exerting its physical shielding effect. Tafel testing results after scratching the coating show that the waterborne epoxy resin coating loses its organic passive protection capability and its corrosion protection fails after damage. The waterborne epoxy resin coating with added MXene-Ni@C-ODD can successfully repair the coating and maintain its cathodic protection function (corrosion current 8.8 × 10⁻⁶). -12 A·cm -2 The modified waterborne epoxy resin coating, after being regulated by a magnetic field, exhibits even better healing performance, with a corrosion current reaching 6.2 × 10⁻⁶. -13 A·cm -2 .

[0056] Due to the strong adhesion of waterborne epoxy resin, the prepared modified waterborne epoxy resin coating can bond firmly to the substrate and is not easy to peel off. Furthermore, the modified waterborne epoxy resin has high hardness, enhancing the wear resistance of the coating. The method of preparing a modified waterborne epoxy resin coating to meet the corrosion protection requirements of the substrate is relatively simple, requires little equipment, and is easy to operate. Adding MXene-Ni@C-ODD to the waterborne epoxy resin coating solves the problem of easy cracking during the curing process, preventing water and corrosive substances from contacting the substrate through the micropores formed inside the cracked coating and causing corrosion. Simultaneously, ultrasonic treatment of MXene-Ni@C-ODD solves the problem of MXene agglomeration in MXene-Ni@C-ODD, increasing its dispersibility in the waterborne epoxy resin coating. This allows MXene-Ni@C-ODD to be more uniformly dispersed in the waterborne epoxy resin coating, resulting in good corrosion protection. Adding a certain concentration of corrosion inhibitor ODD solution to the waterborne epoxy resin coating can protect the coating. When defects occur in the waterborne epoxy resin coating due to changes in the external environment, the corrosion inhibitor plays a role, forming a precipitation layer and an adsorption layer on the substrate surface. This gives the waterborne epoxy resin coating self-healing ability, improves its corrosion resistance, and extends the service life of the substrate. Magnetic control of MXene-Ni@C-ODD solves the problem of disordered distribution of MXene in the coating, allowing MXene in MXene-Ni@C-ODD to be arranged parallel to the substrate, exerting its physical shielding effect and improving the corrosion resistance of the waterborne epoxy resin coating.

[0057] The waterborne epoxy resin coating of this invention exhibits excellent physical shielding and self-healing properties due to the waterborne epoxy coating prepared on the substrate surface through Ni@C-MXene magnetic field orientation control. The proportion of MXene determines the density of the waterborne epoxy coating; insufficient MXene content affects the coating's anti-corrosion effect and physical shielding function. The proportion of MOFs determines the loading and release rate of the coating's corrosion inhibitor, enabling it to be released upon exposure. The parallel arrangement of MXene after magnetic field control provides even better physical shielding properties, enabling it to resist harsh corrosive environments such as:

[0058] The modified waterborne epoxy resin coating of this invention can form a dense protective film on the metal surface, preventing water, oxygen, and corrosive media from contacting the metal. It is widely used for corrosion protection of various metal products. For example, outdoor metal billboards coated with the modified coating can resist humid environments and acid rain erosion, extending their service life. In the chemical industry, many metal equipment come into contact with corrosive media such as acids, alkalis, and salts. The modified waterborne epoxy resin coating, with its excellent chemical corrosion resistance, can protect these devices. For example, metal tanks storing sulfuric acid, when coated with the modified coating on their inner walls, can prevent sulfuric acid from corroding the tanks, ensuring safe operation of the equipment. Using this solution, a smooth, wear-resistant, and stain-resistant coating can be formed on the floors of industrial plants, warehouses, parking lots, and other locations, meeting the needs of different environments. For example, in the workshop floors of some electronics factories, this coating not only provides good wear resistance and corrosion resistance but also has environmentally friendly, non-toxic, and pollution-free characteristics, meeting the requirements of electronics factories for their production environment. In food processing machinery, modified waterborne epoxy resin coatings provide excellent wear resistance and high-temperature resistance, ensuring structural stability even under high temperatures, reducing wear rates over long periods, extending equipment lifespan, and lowering costs. In medical equipment, modified waterborne epoxy resin coatings offer excellent corrosion protection for metal components, preventing rust from disinfectants and cleaning agents used in hospitals, and facilitating cleaning and disinfection.

[0059] Due to the large specific surface area of ​​MXene in magnetic MXene-Ni@C-ODD, it can fully load corrosion inhibitors, acting like microcapsules encapsulating the inhibitors. When the waterborne epoxy resin coating cracks, it can quickly capture metal ions released in the early stages of corrosion, forming a new corrosion-inhibiting layer to achieve self-healing. The self-healing properties of modified waterborne epoxy resin coatings have been widely applied in various fields, especially in scenarios requiring long-term protection, damage resistance, or difficult maintenance. Key application areas include: In marine and shipbuilding engineering, such as offshore platforms, ship hulls, and port facilities, microcapsules encapsulate corrosion inhibitors. When the coating cracks, the inhibitors are released at the corresponding locations, dispersed within the coating. When the coating is subjected to wave erosion or mechanical damage, the capsules rupture, releasing the inhibitors, which combine with metal ions at the crack to form a new slow-release layer, resisting seawater corrosion.

[0060] In summary, the modified waterborne epoxy resin coating of this invention combines the characteristics of physical shielding and strong self-healing to further improve the corrosion resistance of the green organic coating, enabling it to be used for a longer period of time in various harsh corrosive environments.

[0061] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations and simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for preparing a corrosion-resistant modified waterborne epoxy resin coating, characterized in that, Includes the following steps; S1. Remove oil stains from the metal substrate with acetone or anhydrous ethanol, and polish the substrate with sandpaper to increase the surface roughness of the metal substrate; S2. MXene-Ni@C-ODD and a waterborne epoxy curing agent are added to a waterborne epoxy resin and stirred to obtain an MXene-Ni@C-ODD waterborne epoxy resin coating, abbreviated as MO coating; the MXene-Ni@C-ODD is prepared by dissolving a nickel source and an organic ligand in a solvent, adding an MXene suspension, hydrothermally treating at 80~180℃, collecting the precipitate and drying it to obtain MOFs-MXene, annealing at 200~800℃ to obtain MXene-Ni@C, then adding MXene-Ni@C to a corrosion inhibitor heptadecenylamine ethyl imidazoline quaternary ammonium salt solution, loading the corrosion inhibitor onto MXene-Ni@C, collecting the precipitate and drying it to obtain the coating; S3. When using a coating machine to apply the MO coating, magnetic control is applied to make MXene-Ni@C-ODD adhere to the waterborne epoxy resin coating. After curing at room temperature, a modified waterborne epoxy resin coating, abbreviated as mMO coating, is obtained on the surface of the metal substrate.

2. The method for preparing the corrosion-resistant modified waterborne epoxy resin coating according to claim 1, characterized in that, The metal matrix mentioned in step S1 is stainless steel, aluminum alloy, magnesium alloy, titanium alloy or copper alloy.

3. The method for preparing the corrosion-resistant modified waterborne epoxy resin coating according to claim 1, characterized in that, In step S2, the amount of MXene-Ni@C-ODD added is 0.001~20 wt.% of the waterborne epoxy resin; the waterborne epoxy resin is epoxy resin F0716, epoxy resin H1150 or epoxy resin H145, the waterborne epoxy curing agent is F0716, H205B or H206B, and the mass ratio of the waterborne epoxy resin to the waterborne epoxy curing agent is (1~10):

1.

4. The method for preparing the corrosion-resistant modified waterborne epoxy resin coating according to claim 1, characterized in that, The thickness of the mMO coating in step S3 is 10~100μm.

5. The method for preparing the corrosion-resistant modified waterborne epoxy resin coating according to claim 1, characterized in that, The nickel source mentioned in step S2 is NiCl2·6H2O, Ni(NO3)2·6H2O, NiSO4·6H2O, or Ni(OAc)2·4H2O; the organic ligand is 2,3,6,7,10,11-hexahydroxytriphenylene hydrate, o-dibenzoic acid, p-dibenzoic acid, 1,3,5-benzenetricarboxylic acid, or thiophene-2,5-dicarboxylic acid; and the solvent is DMF, water, or ethanol.

6. The method for preparing the corrosion-resistant modified waterborne epoxy resin coating according to claim 1, characterized in that, In step S2, the mass ratio of the nickel source, organic ligand, and solvent is (1~10):(1~10):(1~10); the mass ratio of MXene to MOFs in MOFs-MXene is (1~10):(1~10); and the mass ratio of MXene-Ni@C to heptadecanylamine ethyl imidazoline quaternary ammonium salt in the solution is (1~10):

1.

7. The method for preparing the corrosion-resistant modified waterborne epoxy resin coating according to claim 1, characterized in that, The MXene mentioned in step S2 is Ti3C2T x Ta4C3T x V2CT x Nb2CT x or Ti3CNT x x=1~3; the concentration of the MXene suspension is 0.1~10 mg / mL; the concentration of the heptadecenylaminoethylimidazoline quaternary ammonium salt solution is 1~100 wt.%.

8. A corrosion-resistant modified waterborne epoxy resin coating, characterized in that, The modified waterborne epoxy resin coating is prepared by the method described in any one of claims 1-7.

9. The application of the corrosion-resistant modified waterborne epoxy resin coating of claim 8 in the field of metal surface protection.

Images