Epoxy resin-based nanocomposite protective coating material, preparation method and application thereof

Abstract

The present application belongs to the technical field of functional composite coating materials, and particularly relates to an epoxy resin-based nano-composite protective coating material, a preparation method and application thereof. The method uses natural attapulgite and copper chloride dihydrate as raw materials, and adopts chemical bath deposition and hydrothermal method to load polydopamine-copper and defect-rich cerium oxide into attapulgite respectively, to obtain a defect-rich cerium oxide / polydopamine-copper / attapulgite nano-composite material. Then, the material is mixed with epoxy resin E51 and diluent to obtain an epoxy resin-based protective coating material with both corrosion and algae resistance and photo-thermal deicing functions. The coating material has long-term and complex environment-resistant corrosion resistance, and also has excellent high and low temperature salt spray complex environment aging resistance and anti-microbial adhesion performance, and is suitable for high-voltage transmission and distribution tower, oil field ground equipment metal structure corrosion protection in high-cold regions and humid environments.

Description

Technical Field

[0001] This invention belongs to the field of functional protective coating technology, specifically relating to an epoxy resin-based nanocomposite protective coating, its preparation method, and its application. Background Technology

[0002] In the protection scenarios of metal components such as power transmission towers and oilfield surface equipment in high-altitude and cold regions around the world, corrosion problems are coupled with multiple destructive factors, including high and low temperature cycling shocks, mechanical damage from icing, and algal microbial corrosion. This results in the actual service life of traditional anti-corrosion coatings being far shorter than expected. Specifically, the thermal stress caused by alternating high and low temperatures can damage the interfacial bonding between the coating and the metal substrate, causing coating delamination and debonding. Icing on the coating surface at low temperatures not only generates mechanical pressure due to volume expansion, leading to coating cracking, but also accelerates the penetration of corrosive media during the melting process. Furthermore, after algae resistant to extreme environments adhere to the coating surface, their secreted organic acids, extracellular polymers, and other metabolic products directly erode the coating resin structure, destroying the coating's barrier protection function.

[0003] More importantly, these destructive factors do not act independently, but exhibit a significant synergistic aggravating effect—microcracks in the coating caused by thermal stress provide a penetration channel for corrosive media and algal metabolites; the coverage of algal biofilms exacerbates local electrochemical corrosion; and the mechanical damage from icing further weakens the overall protective capability of the coating. This makes it difficult for single-function anti-corrosion coatings to meet the protection requirements of complex and harsh environments. Therefore, there is an urgent need for a protective coating material that combines anti-corrosion and anti-algae properties with photothermal de-icing functions to solve this problem. Summary of the Invention

[0004] To address the problem of multiple coupled corrosion faced by metal equipment in high-altitude and cold regions worldwide, this invention provides an epoxy resin-based nanocomposite protective coating, its preparation method, and its application.

[0005] An epoxy resin-based protective coating material possesses both anti-corrosion and anti-algae properties, as well as photothermal de-icing capabilities. Through a special structural design and component control, the coating effectively enhances the interfacial bonding stability between the coating and the metal substrate, strengthening its resistance to high and low temperature cycling shocks. Simultaneously, it exhibits active photothermal de-icing performance, mitigating mechanical damage to the coating caused by icing. Furthermore, the coating allows for the controlled release of active ingredients, effectively inhibiting algae adhesion and metabolic erosion, thereby achieving long-term protection for metal components. This multifunctional coating effectively solves the problem of traditional anti-corrosion coatings failing easily in cold and complex environments, providing an ideal technical solution for the protection of metal equipment in power transmission and transformation, oil fields, and other fields in cold regions.

[0006] The technical solution adopted in this invention is as follows:

[0007] A method for preparing an epoxy resin-based nanocomposite protective coating includes the following steps:

[0008] Step 1: First, a certain mass of attapulgite, dopamine hydrochloride, and tris(hydroxymethyl)aminomethane are dispersed in deionized water, and 28% hydrochloric acid is added to adjust the pH to 7-9 to obtain precursor solution A. A certain mass of copper chloride dihydrate is dispersed in deionized water, and then the pH is adjusted to 8-9 with 0.1 mol / L ammonia water to obtain precursor solution B. Precursor solution B is added dropwise to precursor solution A at a rate of 5-6 ml / min. The reaction temperature is 20-30 ℃, and the reaction time is 24-48 h. After the reaction, the mixture is washed with deionized water, sonicated, centrifuged 3-5 times, and freeze-dried at -50~-30 ℃ for 20-24 h to obtain polydopamine-copper / attapulgite nanoparticle powder.

[0009] Step 2: Weigh a certain mass of polydopamine-copper attapulgite nanoparticle powder, cerium nitrate tetrahydrate, and potassium D-gluconate and disperse them in deionized water. Add 0.1 mol / L ammonia water dropwise to adjust the pH to 7.5~9.5. Place the mixture in a hydrothermal reactor for hydrothermal reaction. Then, wash the resulting mixture with deionized water, sonicate, centrifuge 3-5 times, and freeze-dry at -50~-30 ℃ for 24~48 h to obtain defect-rich cerium oxide / polydopamine-copper attapulgite nanoparticle powder.

[0010] Step 3: Weigh a certain mass of defect-rich cerium oxide / polydopamine-copper / attapulgite nanoparticle powder, mix it with epoxy resin E51 and diluent C, stir at 25 ℃ for 3 h, and sonicate for 10 min to obtain coating precursor slurry A; weigh a certain amount of curing agent diaminodiphenylmethane and diluent C, stir at 25 ℃ for 1 h to obtain coating precursor slurry B; mix slurry A and slurry B, stir at 50~90 ℃ for 30~15 min to obtain epoxy resin-based nanocomposite protective coating.

[0011] Furthermore, in step one, the mass ratio of attapulgite to dopamine hydrochloride is 1:1 to 1:8 g; and the concentration of tris(hydroxymethyl)aminomethane added to precursor solution A is 0.1-0.4%.

[0012] Furthermore, in step one, the amount of copper chloride dihydrate added is such that the molar concentration of copper ions in precursor solution B is 0.01-0.5 mol / L.

[0013] Furthermore, in step two, the mass ratio of polydopamine-copper / attapulgite nanoparticle powder to cerium nitrate tetrahydrate is 1:5-2:1, and the amount of potassium D-gluconate added is 0.1-1% of the total mass of polydopamine-copper / attapulgite nanoparticle powder and cerium nitrate tetrahydrate.

[0014] Furthermore, in step two, the hydrothermal reaction temperature is 160~195℃, and the reaction time is 3-6 h.

[0015] Furthermore, in step three, the amount of defect-rich cerium oxide / polydopamine-copper / attapulgite nanoparticle powder added is 1 wt% to 6 wt% of the total volume of epoxy resin.

[0016] Furthermore, in step three, the diluent C is a mixture of tert-butanol, acetone, and ethanol, with a volume ratio of 2:6:1 to 3:1:2.

[0017] An epoxy resin-based nanocomposite protective coating prepared by any of the above methods.

[0018] An epoxy resin-based nanocomposite protective coating, as described above, is used in both corrosion and algae prevention and photothermal de-icing of metal components.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] This invention employs chemical bath deposition and hydrothermal methods to prepare an epoxy resin-based protective coating material that combines corrosion resistance, algae resistance, and photothermal de-icing functions. In the composite coating, defect-rich cerium oxide and polydopamine-copper form a heterojunction, achieving photothermal de-icing while simultaneously releasing copper ions in a controlled manner to effectively inhibit the adhesion of algae and other microorganisms. The defect-rich cerium oxide reduces the organic compatibility between polydopamine-copper and E51 epoxy resin. By reducing the difference in thermal expansion coefficients between the nanoparticles and the epoxy resin matrix, the coating's resistance to high and low temperature impacts is significantly improved, providing effective protection for metals even in environments with alternating high and low temperatures.

[0021] The protective coating prepared by this invention, through special structural design and component regulation, effectively improves the interfacial bonding stability between the coating and the metal substrate, and enhances the coating's ability to resist high and low temperature cycling shocks. It also possesses active photothermal de-icing properties, mitigating mechanical damage to the coating caused by icing. Furthermore, the coating allows for the controlled release of active ingredients, effectively inhibiting algae adhesion and metabolic erosion, thereby achieving long-term protection for metal components. This multifunctional coating effectively solves the problem of traditional anti-corrosion coatings easily failing in cold and complex environments, providing an ideal technical solution for the protection of metal equipment in power transmission and transformation, oil fields, and other fields in cold regions. The epoxy resin-based protective coating material prepared by this invention, which combines anti-corrosion, anti-algae, and photothermal de-icing functions, possesses excellent acid and alkali resistance as well as crude oil (shale oil) corrosion resistance, and has broad practical application prospects. Attached Figure Description

[0022] Figure 1Examples 1, 2, and 3 show actual images of the coatings applied to a Q235B steel corrosion-resistant hanging plate, a 304 stainless steel pipe surface, and a glass surface, respectively.

[0023] Figure 2 Scanning electron microscope image of defect-rich cerium oxide / polydopamine-copper attapulgite nanoparticle powder in Example 1;

[0024] Figure 3 From left to right are actual photos of the corrosion-resistant Q2535B steel hanging plates after high and low temperature cycling shock and 120 h salt spray test obtained from Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3.

[0025] Figure 4 From left to right, these are Example 1 and Comparative Example 3, showing the melting effect of a 2 mm ice layer after 5 minutes of 1.0 solar intensity irradiation.

[0026] Figure 5 This is a comparison chart of the total chlorophyll content in the Chlorella algal solutions obtained in Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3. Detailed Implementation

[0027] The specific content of the present invention will be further explained in detail below with reference to the embodiments and accompanying drawings.

[0028] Example 1

[0029] Step 1: First, disperse 0.5 g of attapulgite, 1.5 g of dopamine hydrochloride, and 0.12 g of tris(hydroxymethyl)aminomethane in 50 ml of deionized water, add 28% hydrochloric acid, and adjust the pH to 7.5 to obtain precursor solution A. Then, disperse 1.02 g of copper chloride dihydrate in 50 ml of deionized water to achieve a copper ion molar concentration of 0.35 mol / L. Adjust the pH to 8.35 with 0.1 mol / L ammonia water to obtain precursor solution B. Add precursor solution B dropwise to precursor solution A at a rate of 5-6 ml / min. The reaction temperature is 25 ℃, and the reaction time is 24 h. After the reaction is complete, wash the mixture with deionized water, sonicate, centrifuge 3-5 times, and freeze-dry at -50~-30 ℃ for 20~24 h to obtain polydopamine-copper attapulgite nanoparticle powder.

[0030] Step 2: Weigh 1 g of polydopamine-copper attapulgite nanoparticle powder, 2.5 g of cerium nitrate tetrahydrate, and 0.014 g of potassium D-gluconate, disperse them in 30 ml of deionized water, add 0.1 mol / L ammonia dropwise to adjust the pH to 7.8, place in a hydrothermal reactor, and react at 170 ℃ for 360 min to obtain a suspension of defect-rich cerium oxide-modified polydopamine-copper attapulgite nanoparticle precursors; then, wash the mixture with deionized water, sonicate, centrifuge 3-5 times, and freeze-dry at -45 ℃ for 36 h to obtain defect-rich cerium oxide / polydopamine-copper / attapulgite nanoparticle powder.

[0031] Step 3: Weigh 0.088 g of the defect-rich cerium oxide / polydopamine-copper / attapulgite nanocomposite material and mix it with 3 ml of epoxy resin E51. Sonicate the mixture for 10 min to obtain coating precursor slurry A. Weigh 1.059 g of curing agent diaminodiphenylmethane and diluent C (1 ml of tert-butanol, 3 ml of acetone, and 1 ml of ethanol, respectively), mix them, and stir at 25 ℃ for 3 h, then at 25 ℃ for 1 h to obtain coating precursor slurry B. Mix slurry A and slurry B, and stir at 80 ℃ for 16 min to prepare a defect-rich cerium oxide / polydopamine-copper / attapulgite nanocomposite protective coating. Spray this coating onto the surfaces of a 10×10×2 mm Q235B electrode sheet and a 50×20×2 mm Q235B etching pad, with coating thicknesses of 75 μm and 1000 μm, respectively. Cur at 60 ℃ for 21 h.

[0032] Example 2

[0033] Step 1: First, disperse 0.5 g of attapulgite, 1.5 g of dopamine hydrochloride, and 0.12 g of tris(hydroxymethyl)aminomethane in 50 ml of deionized water, add 28% hydrochloric acid, and adjust the pH to 7.5 to obtain precursor solution A. Then, disperse 1.02 g of copper chloride dihydrate in 50 ml of deionized water to achieve a copper ion molar concentration of 0.35 mol / L. Adjust the pH to 8.35 with 0.1 mol / L ammonia water to obtain precursor solution B. Add precursor solution B dropwise to precursor solution A at a rate of 5-6 ml / min. The reaction temperature is 25 ℃, and the reaction time is 24 h. After the reaction is complete, wash the mixture with deionized water, sonicate, centrifuge 3-5 times, and freeze-dry at -50~-30 ℃ for 20~24 h to obtain polydopamine-copper attapulgite nanoparticle powder.

[0034] Step 2: Weigh 1 g of polydopamine-copper attapulgite nanoparticle powder, 2.5 g of cerium nitrate tetrahydrate, and 0.014 g of potassium D-gluconate, disperse them in 30 ml of deionized water, add 0.1 mol / L ammonia dropwise to adjust the pH to 7.8, place the mixture in a hydrothermal reactor, and react at 170 ℃ for 360 min. Then, wash the mixture with deionized water, sonicate, centrifuge 3-5 times, and freeze-dry at -45 ℃ for 36 h to obtain defect-rich cerium oxide / polydopamine-copper / attapulgite nanoparticle powder.

[0035] Step 3: Weigh 0.088 g of the defect-rich cerium oxide / polydopamine-copper / attapulgite nanocomposite material and mix it with 3 ml of epoxy resin E51. Sonicate the mixture for 10 min to obtain coating precursor slurry A. Weigh 1.059 g of curing agent diaminodiphenylmethane and diluent C (1 ml of tert-butanol, 3 ml of acetone, and 1 ml of ethanol, respectively). Mix the mixture at 25 ℃ for 3 h and then at 25 ℃ for 1 h to obtain coating precursor slurry B. Mix slurry A and slurry B and stir at 80 ℃ for 16 min to prepare a defect-rich cerium oxide / polydopamine-copper / attapulgite nanocomposite protective coating. Spray this coating onto the surface of a 304 stainless steel pipe to a thickness of 1000 μm. Cur at 60 ℃ for 21 h.

[0036] Example 3

[0037] Step 1: First, disperse 0.5 g of attapulgite, 1.5 g of dopamine hydrochloride, and 0.12 g of tris(hydroxymethyl)aminomethane in 50 ml of deionized water, add 28% hydrochloric acid, and adjust the pH to 7.5 to obtain precursor solution A. Then, disperse 1.02 g of copper chloride dihydrate in 50 ml of deionized water to achieve a copper ion molar concentration of 0.35 mol / L. Adjust the pH to 8.35 with 0.1 mol / L ammonia water to obtain precursor solution B. Add precursor solution B dropwise to precursor solution A at a rate of 5-6 ml / min. The reaction temperature is 25 ℃, and the reaction time is 24 h. After the reaction is complete, wash the mixture with deionized water, sonicate, centrifuge 3-5 times, and freeze-dry at -50~-30 ℃ for 20~24 h to obtain polydopamine-copper attapulgite nanoparticle powder.

[0038] Step 2: Weigh 1 g of polydopamine-copper attapulgite nanoparticle powder, 2.5 g of cerium nitrate tetrahydrate, and 0.014 g of potassium D-gluconate, disperse them in 30 ml of deionized water, add 0.1 mol / L ammonia dropwise to adjust the pH to 7.8, place in a hydrothermal reactor, and react at 170 ℃ for 360 min to obtain a suspension of defect-rich cerium oxide-modified polydopamine-copper attapulgite nanoparticle precursors; then, wash the mixture with deionized water, sonicate, centrifuge 3-5 times, and freeze-dry at -45 ℃ for 36 h to obtain defect-rich cerium oxide / polydopamine-copper / attapulgite nanoparticle powder.

[0039] Step 3: Weigh 0.088 g of the defect-rich cerium oxide / polydopamine-copper / attapulgite nanocomposite material and mix it with 3 ml of epoxy resin E51. Sonicate the mixture for 10 min to obtain coating precursor slurry A. Weigh 1.059 g of curing agent diaminodiphenylmethane and diluent C (1 ml of tert-butanol, 3 ml of acetone, and 1 ml of ethanol), mix them, and stir at 25 ℃ for 3 h, then at 25 ℃ for 1 h to obtain coating precursor slurry B. Mix slurry A and slurry B, and stir at 80 ℃ for 16 min to prepare a defect-rich cerium oxide / polydopamine-copper / attapulgite nanocomposite protective coating. Spray this coating onto the glass surface to a thickness of 1000 μm. Cur at 60 ℃ for 21 h.

[0040] Comparative Example 1

[0041] Step 1: First, disperse 0.5 g of attapulgite, 1.5 g of dopamine hydrochloride, and 0.12 g of tris(hydroxymethyl)aminomethane in 50 ml of deionized water, add 28% hydrochloric acid, and adjust the pH to 7.5 to obtain precursor solution A. Then, disperse 1.02 g of copper chloride dihydrate in 50 ml of deionized water to achieve a copper ion molar concentration of 0.35 mol / L. Adjust the pH to 8.35 with 0.1 mol / L ammonia water to obtain precursor solution B. Add precursor solution B dropwise to precursor solution A at a rate of 5-6 ml / min. The reaction temperature is 25 ℃, and the reaction time is 24 h. After the reaction is complete, wash the mixture with deionized water, sonicate, centrifuge 3-5 times, and freeze-dry at -50~-30 ℃ for 20~24 h to obtain polydopamine-copper attapulgite nanoparticle powder.

[0042] Step 2: Weigh 0.088 g of polydopamine-copper / attapulgite nanocomposite material and mix it with 3 ml of epoxy resin E51, then sonicate for 10 min to obtain coating precursor slurry A. Weigh 1.059 g of curing agent diaminodiphenylmethane and diluent C (1 ml of tert-butanol, 3 ml of acetone, and 1 ml of ethanol, respectively), mix them, and stir at 25 ℃ for 3 h, then at 25 ℃ for 1 h to obtain coating precursor slurry B. Mix slurry A and slurry B, and stir at 80 ℃ for 16 min to prepare a polydopamine-copper / attapulgite nanocomposite protective coating. Spray this coating onto the surface of a 10×10×2 mm Q235B electrode sheet and a 50×20×2 mm Q235B etching pad, with coating thicknesses of 75 μm and 1000 μm, respectively. Curing is performed at 60 ℃ for 21 h.

[0043] Comparative Example 2

[0044] Step 1: First, disperse 0.5 g of attapulgite, 1.5 g of dopamine hydrochloride, and 0.12 g of tris(hydroxymethyl)aminomethane in 50 ml of deionized water, add 28% hydrochloric acid, and adjust the pH to 7.5 to obtain precursor solution A. Then, disperse 1.02 g of copper chloride dihydrate in 50 ml of deionized water to achieve a copper ion molar concentration of 0.35 mol / L. Adjust the pH to 8.35 with 0.1 mol / L ammonia water to obtain precursor solution B. Add precursor solution B dropwise to precursor solution A at a rate of 5-6 ml / min. The reaction temperature is 25 ℃, and the reaction time is 24 h. After the reaction is complete, wash the mixture with deionized water, sonicate, centrifuge 3-5 times, and freeze-dry at -50~-30 ℃ for 20~24 h to obtain polydopamine-copper attapulgite nanoparticle powder.

[0045] Step 2: Weigh 0.088 g of attapulgite nanocomposite material and mix it with 3 ml of epoxy resin E51, then sonicate for 10 min to obtain coating precursor slurry A. Weigh 1.059 g of curing agent diaminodiphenylmethane and diluent C (1 ml of tert-butanol, 3 ml of acetone, and 1 ml of ethanol, respectively), mix them, and stir at 25 ℃ for 3 h, then at 25 ℃ for 1 h to obtain coating precursor slurry B. Mix slurry A and slurry B, and stir at 80 ℃ for 16 min to prepare an attapulgite nanocomposite protective coating. Spray this coating onto the surface of a 10×10×2 mm Q235B electrode sheet and a 50×20×2 mm Q235B etching pad, with coating thicknesses of 75 μm and 1000 μm, respectively. Curing is performed at 60 ℃ for 21 h.

[0046] Comparative Example 3

[0047] Step 1: Measure 3 ml of epoxy resin E51 and sonicate for 10 min to prepare coating precursor slurry A; weigh 1.059 g of curing agent diaminodiphenylmethane and diluent C (1 ml of tert-butanol, 3 ml of acetone, and 1 ml of ethanol, respectively), mix, stir at 25℃ for 3 h, and then stir at 25℃ for 1 h to prepare coating precursor slurry B; mix slurry A and slurry B, stir at 80℃ for 16 min to prepare an epoxy resin protective coating, and spray it onto the surface of a 10×10×2 mm Q235B electrode sheet and a 50×20×2 mm Q235B etching pad, with coating thicknesses of 75 μm and 1000 μm, respectively. Curing at 60℃ for 21 h.

[0048] Figure 1 Examples 1, 2, and 3 show actual images of the resulting coatings on a Q235B steel corrosion-resistant hanging plate, a 304 stainless steel pipe surface, and a glass surface, respectively. It is evident that the coating prepared by the defect-rich cerium oxide / polydopamine-copper / attapulgite nanocomposite protective coating is suitable for substrates of various shapes and can also be used for the protection of glass-based devices.

[0049] Figure 2 The image shows a SEM image of a defect-rich cerium oxide / polydopamine-copper / attapulgite nanoparticle obtained in Example 1. The attapulgite encapsulated by polydopamine-copper and the carbon-doped oxygen-vacancy cerium oxide loaded on the surface of polydopamine-copper in spherical or grape-like patterns are clearly visible.

[0050] The thickness of the polydopamine-copper coated attapulgite is 50-1000 nm, and the defect-rich cerium oxide is a spherical or grape-like aggregate with an area of ​​100-400 nm.

[0051] Figure 3 From left to right, these are examples 1, 2, and 3, showing the actual effect of the anti-corrosion coatings prepared from epoxy resin-based protective coating materials that combine anti-corrosion, anti-algae, and photothermal de-icing functions. The images depict the coatings after a 120-hour salt spray test following high and low temperature cycling. In examples 1, 2, and 3, the coatings either detached or completely peeled off, while in example 1, detachment occurred and the metal substrate did not corrode. This demonstrates that the anti-corrosion coating prepared from the epoxy resin-based protective coating material obtained in example 1, which combines anti-corrosion, anti-algae, and photothermal de-icing functions, possesses excellent resistance to high and low temperature damage.

[0052] Figure 4From left to right, these are Example 1 and Comparative Example 3, respectively. The anti-corrosion coating prepared from an epoxy resin-based protective coating material that combines anti-corrosion, anti-algae, and photothermal de-icing functions was irradiated with 1.0 solar intensity for 5 minutes, resulting in the melting effect of a 2 mm ice layer. It can be significantly observed that Example 1 has a larger de-icing ring compared to Comparative Example 1, demonstrating superior de-icing capability.

[0053] Figure 5 The graph shows a comparison of the total chlorophyll content in the Chlorella algal solutions obtained in Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3. It can be clearly observed that the chlorophyll content in Chlorella in Example 1 also decreased, proving that the coating prepared in Example 1 significantly hindered the growth of Chlorella and had an anti-algae adhesion effect.

[0054] According to the GB / T 10125-2021 neutral salt spray test standard and the ASTM G59 standard test method for measuring electrodynamic polarization resistance, it was found that when the amount of defect-rich cerium oxide / polydopamine-copper attapulgite nanoparticle powder added is 2~3 wt%, the resulting coating corrosion area is less than 0.1%, which is the optimal level. Furthermore, the coating material is suitable for spraying on flat, curved, or complex surfaces. After curing, the coating is dense and uniform, and the EIS coating test shows that the 0.1Hz characteristic frequency impedance value remains at 10 for 40 days. 7 Ω.

[0055] According to the GB / T 23932 neutral salt spray test standard, a periodic temperature-varying salt spray test was introduced. It was found that when the amount of defect-rich cerium oxide / polydopamine-copper attapulgite nanoparticle powder added was 2~3 wt%, the resulting coating had a corrosion area of ​​less than 0.1%, which is the optimal level. After 50 cycles of periodic temperature variation and 120 hours of salt spray test, no obvious corrosion occurred in the metal substrate, and the coating was firmly bonded to the substrate.

[0056] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing an epoxy resin-based nanocomposite protective coating, characterized in that, Includes the following steps: Step 1: First, a certain mass of attapulgite, dopamine hydrochloride, and tris(hydroxymethyl)aminomethane are dispersed in deionized water. 28% hydrochloric acid is added to adjust the pH to 7-9 to obtain precursor solution A. A certain mass of copper chloride dihydrate is dispersed in deionized water, and then the pH is adjusted to 8-9 with 0.1 mol / L ammonia water to obtain precursor solution B. Precursor solution B is added dropwise to precursor solution A at a rate of 5-6 ml / min. The reaction temperature is 20-30 ℃, and the reaction time is 24-48 h. After the reaction, the mixture is washed with deionized water, sonicated, centrifuged 3-5 times, and freeze-dried at -50~-30 ℃ for 20-24 h to obtain polydopamine-copper / attapulgite nanoparticle powder. Step 2: Weigh a certain mass of polydopamine-copper attapulgite nanoparticle powder, cerium nitrate tetrahydrate, and potassium D-gluconate and disperse them in deionized water. Add 0.1 mol / L ammonia water dropwise to adjust the pH to 7.5~9.

5. Place the mixture in a hydrothermal reactor for hydrothermal reaction. Then, wash the resulting mixture with deionized water, sonicate, centrifuge 3-5 times, and freeze-dry at -50~-30 ℃ for 24~48 h to obtain defect-rich cerium oxide / polydopamine-copper attapulgite nanoparticle powder. Step 3: Weigh a certain mass of defect-rich cerium oxide / polydopamine-copper / attapulgite nanoparticle powder, mix it with epoxy resin E51 and diluent C, stir at 25 ℃ for 3 h, and sonicate for 10 min to obtain coating precursor slurry A; weigh a certain amount of curing agent diaminodiphenylmethane and diluent C, stir at 25 ℃ for 1 h to obtain coating precursor slurry B; mix slurry A and slurry B, stir at 50~90 ℃ for 30~15 min to obtain epoxy resin-based nanocomposite protective coating.

2. The preparation method of the epoxy resin-based nanocomposite protective coating as described in claim 1, characterized in that, In step one, the mass ratio of attapulgite to dopamine hydrochloride is 1:1 to 1:8 g; tris(hydroxymethyl)aminomethane is added to precursor solution A at a concentration of 0.1-0.4%.

3. The preparation method of the epoxy resin-based nanocomposite protective coating as described in claim 1, characterized in that, In step one, the amount of copper chloride dihydrate added is such that the molar concentration of copper ions in precursor solution B is 0.01-0.5 mol / L.

4. The preparation method of the epoxy resin-based nanocomposite protective coating as described in claim 1, characterized in that, In step two, the mass ratio of polydopamine-copper / attapulgite nanoparticle powder to cerium nitrate tetrahydrate is 1:5-2:1, and the amount of potassium D-gluconate added is 0.1-1% of the total mass of polydopamine-copper / attapulgite nanoparticle powder and cerium nitrate tetrahydrate.

5. The preparation method of the epoxy resin-based nanocomposite protective coating as described in claim 1, characterized in that, In step two, the hydrothermal reaction temperature is 160~195℃, and the reaction time is 3-6 h.

6. The preparation method of the epoxy resin-based nanocomposite protective coating as described in claim 1, characterized in that, In step three, the amount of defect-rich cerium oxide / polydopamine-copper / attapulgite nanoparticle powder added is 1 wt% to 6 wt% of the total volume of epoxy resin.

7. The preparation method of the epoxy resin-based nanocomposite protective coating as described in claim 1, characterized in that, In step three, diluent C is a mixture of tert-butanol, acetone, and ethanol, with a volume ratio of 2:6:1 to 3:1:

2.

8. An epoxy resin-based nanocomposite protective coating prepared by the preparation method according to any one of claims 1 to 7.

9. The application of the epoxy resin-based nanocomposite protective coating as described in claim 8 in both corrosion and algae prevention and photothermal de-icing of metal components.

Images