A method for producing a multifunctional anti-adhesion coating

Abstract

The application discloses a preparation method of a multifunctional anti-adhesion coating, and relates to the field of safe oil and gas pipeline transportation. The method mainly comprises the following steps: forming a stable metal organic framework (MOFs) structure by dissolving selected metal salts and organic ligands in an organic solvent and ultrasonic stirring; meanwhile, preparing nanoparticles by mixing a nitrate solution under alkaline conditions and hydrothermal reaction; then, intercalating and assembling the prepared MOFs and nanoparticles, and spraying the same on a pretreated steel sheet substrate to form a multifunctional coating. The coating has corrosion resistance and anti-adhesion performance, and through simple spin coating and spraying process steps, the practicability and cost-effectiveness of the preparation method are ensured. The coating can effectively prevent hydrate aggregation and blockage, improve pipeline flowability, and reduce energy consumption, thereby providing a feasible scheme for preparing a coating with excellent anti-adhesion and corrosion resistance for a deepwater oil and gas pipeline and providing scientific support for the flow transportation guarantee of the oil and gas pipeline.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of safe transportation of oil and gas pipelines, in particular to a preparation method of multifunctional anti-adhesion coating. BACKGROUND

[0002] In the oil and gas industry, efficient and safe pipeline transportation has always been a core problem. Natural gas hydrate (NGH) is a solid crystalline compound formed by methane molecules and water molecules under low temperature and high pressure conditions. During pipeline transportation, this solid particle can partially or completely block the pipeline, causing production interruption, equipment damage and personal injury.

[0003] Traditional methods to inhibit the formation of natural gas hydrate mainly involve injecting low-dose hydrate inhibitors such as methanol or ethylene glycol. In recent years, the development of low-adhesion surfaces has become a new method to solve the problem of hydrate nucleation and deposition on the pipe wall. The new low-adhesion surface design effectively reduces the adhesion between hydrate and surface through hydrodynamic shear stress. The pioneers of this technology successfully prepared a biomimetic superhydrophobic coating, which significantly reduced the adhesion of hydrate from a higher value. Studies have shown that surface modification, nanoparticle addition and other means can also effectively reduce the adhesion of hydrate. However, existing technologies often ignore the mechanical stability required in pipeline transportation. SUMMARY

[0004] Based on the above technical problems, the present application provides a preparation method of multifunctional anti-adhesion coating, which can effectively solve the problem of adhesion of natural gas hydrate in multiphase flow pipeline.

[0005] The technical solution adopted by the present application is:

[0006] A preparation method of multifunctional anti-adhesion coating, comprising the following steps:

[0007] (1) Preparation of metal organic framework

[0008] Dissolve the metal salt in the organic solvent to obtain a metal salt solution; dissolve the organic ligand in deionized water to obtain an organic ligand solution; then mix the metal salt solution and the organic ligand solution, and react to obtain a reaction liquid one; centrifugal washing and drying of the reaction liquid one obtain the metal organic framework;

[0009] (2) Preparation of nanoparticles

[0010] Add nitrate to deionized water to obtain a nitrate solution, then add an alkaline solution to the nitrate solution to adjust the pH value to obtain a substrate solution;

[0011] The substrate solution is moved into a hydrothermal reactor, and a reaction is carried out to obtain a reaction liquid II; the reaction liquid II is centrifuged, washed, and dried to obtain nanoparticles;

[0012] (3) Preparation of metal organic framework intercalation

[0013] The metal organic framework in step (1) is dissolved in an organic solvent to obtain a metal organic framework solution; the nanoparticles in step (2) are added to the metal organic framework solution, and a modification solution is further added; the mixture is stirred and reacted; after the reaction is completed, the mixture is centrifuged, washed, and dried to obtain a metal organic framework intercalation;

[0014] (4) Pretreatment of steel sheet substrate

[0015] The steel sheet substrate is polished using sandpaper and then ultrasonically cleaned; the substrate is dried under N2 atmosphere and is ready for use;

[0016] (5) Preparation of base layer

[0017] The pretreated steel sheet substrate in step (4) is coated with a buffer coating and a curing agent by a spin coater, and is then heated to form an uncured base layer;

[0018] (6) Assembly of coating

[0019] The metal organic framework intercalation obtained in step (3) is dissolved in a continuous phase, and is then sprayed onto the uncured base layer in step (5); the mixture is naturally cured at room temperature to obtain a multifunctional anti-adhesion coating.

[0020] Preferably, in step (1), the metal salt is copper acetate, zinc acetate, aluminum acetate, or nickel acetate; the organic solvent is ethanol, dimethylformamide, or dimethyl sulfoxide; and the organic ligand is trimellitic acid, terephthalic acid, or mellitic acid.

[0021] The concentration of the metal salt solution is 1.5-2.0 mol / L, the concentration of the organic ligand solution is 92%-95% (mass fraction), and the amount ratio of the metal salt to the organic ligand is 1:5-1:6 (molar ratio).

[0022] Preferably, in step (1), the mixture of the metal salt solution and the organic ligand solution is first subjected to ultrasonic treatment, and the ultrasonic treatment time is controlled to be 20-30 min.

[0023] Then, the mixture is stirred, the stirring speed is controlled to be 800-1000 r / min, the reaction temperature is controlled to be 45-60℃, and the reaction time is controlled to be 5-6 h.

[0024] After the reaction, the mixture is centrifuged and washed with anhydrous ethanol for 3-5 times, the centrifugation speed is controlled to be 5000-6000 r / min, the drying temperature is controlled to be 65-70℃, and the drying time is controlled to be 5-6 h.

[0025] Preferably, in step (2), the nitrate salt is cerium nitrate, copper nitrate or zinc nitrate, and the concentration of the nitrate salt solution is 1.5-2.0 mol / L;

[0026] The alkaline solution is a NaOH solution, and the concentration of the NaOH solution is 0.40-0.45 mol / L;

[0027] When the alkaline solution is added to the nitrate salt solution to adjust the pH value, N2 is introduced;

[0028] The pH value is adjusted to 12-14.

[0029] Preferably, in step (2), the substrate solution is stirred before being moved into the hydrothermal reactor, the stirring temperature is controlled to be 25-30°C, the stirring speed is controlled to be 500-600 r / min, and the stirring time is controlled to be 1-2 h;

[0030] The reaction temperature in the hydrothermal reactor is controlled to be 90-100°C, and the reaction time is controlled to be 12-24 h;

[0031] After the reaction, the reaction solution is washed by centrifugation using deionized water until the pH value of the reaction solution is 7;

[0032] The drying temperature is controlled to be 65-70°C.

[0033] Preferably, in step (3), the organic solvent is methanol, dimethylformamide or dimethyl sulfoxide; and the modification solution is a stearic acid solution, a 1H, 2H, 2H-perfluorodecyltrimethoxysilane solution, a 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane solution or a trichloro(1H, 1H, 2H, 2H-perfluorooctyl)silane solution.

[0034] Preferably, in step (3),

[0035] 0.2-0.4 g of the metal-organic framework is dissolved in 30-50 mL of the organic solvent; the addition amount of the nanoparticles is 0.1-0.2 g; the addition amount of the modification solution is 200-300 μL; the mass concentration of the modification solution is 8.5%-10%; for example, taking the stearic acid solution, the stearic acid is the solute, water is the solvent, and the mass concentration of the stearic acid solution can be selected to be 8.5%, 9% or 10%;

[0036] The stirring temperature is controlled to be 25-30°C, the stirring speed is controlled to be 500-600 r / min, and the stirring time is controlled to be 1-2 h;

[0037] After the reaction, the reaction solution is washed by centrifugation using deionized water for 3-5 times; the drying temperature is controlled to be 50-60°C, the dried particles are ground into powder using a mortar, and the powder is sieved using a 100-mesh sieve to obtain the metal-organic framework intercalation.

[0038] Preferably, in step (4): the steel sheet substrate is selected from one of X65 steel, X80 steel, L245 steel; the sandpaper is 280 mesh, 320 mesh, 400 mesh, 600 mesh, 800 mesh, 1000 mesh SiC sandpaper; in the ultrasonic cleaning process, petroleum ether and anhydrous ethanol are used in sequence.

[0039] Preferably, in step (5): the buffer coating is selected from polyacrylic resin, polyurethane or epoxy resin; the curing agent is selected from polyisocyanate, polyhexamethylene lactam alcohol or oxirane amine; the mass ratio of the curing agent to the buffer coating is 1:1.5-1:3.

[0040] The rotation speed of the spin coater is controlled to be 1300-2000 r / min, the spin coating time is 20-30 s, and the heating temperature is 50-60 DEG C, and the heating time is 10-15 min.

[0041] Preferably, in step (6): the continuous phase is anhydrous ethanol or ethyl acetate.

[0042] The spraying parameters are controlled as follows: the air pressure is 0.3-0.5 MPa, the spray gun height is 15-20 cm, and the atomization value is 1.0-1.5 turns.

[0043] The beneficial technical effects of the present application are:

[0044] The present application adopts a spin coating-spraying process to prepare a multifunctional anti-adhesion coating on the surface of a steel sheet through the inspiration of the cat paw structure of bionics. The coating is composed of a base layer and an anti-adhesion layer, has excellent superhydrophobicity, corrosion resistance and wear resistance, can effectively prevent the adhesion and blockage of natural gas hydrates in deepwater oil and gas pipelines, and improves the flowability and safe transportation of the pipeline.

[0045] Specifically, the present application has the following advantages:

[0046] 1. Metal organic frameworks (MOFs) have highly adjustable pore structures and extremely high specific surface areas, which provide an excellent performance basis for their application in coatings. The porosity of MOFs structure helps to effectively embed nanoparticles, enhancing the adsorption and barrier properties of the coating.

[0047] 2. The multifunctional coating has excellent superhydrophobic properties, which can reduce the adhesion and retention of liquids in the pipeline, reduce the formation and accumulation of hydrates, thereby preventing blockage and pressure loss.

[0048] 3. The anti-adhesion layer has corrosion and erosion resistance, which can protect the metal surface of the pipeline under the action of corrosive media and chemicals in the pipeline, prolonging the service life of the pipeline.

[0049] 4. The present invention not only actively prevents the formation and blockage of hydrates, but also passively delays the growth and accumulation of hydrates, greatly reducing the frequency and cost of pipeline maintenance and cleaning.

[0050] 5. The spin-spray process is simple and low-cost.

[0051] The advantages of the present invention will be described in more detail below in combination with the principles:

[0052] (1) The present invention provides a superior performance basis for the application of metal-organic frameworks (MOFs) in coatings by preparing MOFs with highly adjustable pore structure and extremely high specific surface area. The porosity of MOFs helps to effectively embed nanoparticles, enhancing the adsorption and barrier properties of the coating. After reasonable design and optimization, the structure of MOFs can have high stability, maintaining its structural integrity during the service life of the coating, providing reliability for long-term use.

[0053] (2) Among nanomaterials, nanoceria has excellent wear resistance, with high hardness that effectively resists surface wear and friction. At the same time, nanoceria has a certain lubricity on the surface, which helps to reduce frictional resistance, which is crucial for engineering applications that require low friction coefficients. As a component of the coating, nanoceria can form a surface with excellent wear resistance, providing protection in mechanical devices, tools, automotive parts, etc. Nanocopper oxide has excellent antioxidant properties, which help to enhance the durability of the coating. In the coating, copper oxide particles can provide additional protection against the erosion of harmful gases and chemicals, extending the service life of the coating. The surface properties of nanometer zinc oxide help to form a uniform and dense surface structure, making it exhibit good anti-adhesion properties. This plays an important role in preventing the adhesion of substances on the surface, reducing adhesion and adhesion problems, and improving the smoothness and cleanliness of the surface.

[0054] (3) The metal-organic frameworks and nanoparticles in the coating of the present invention work synergistically to provide effective corrosion and erosion protection for the pipeline. Under the action of corrosive media and chemicals in the pipeline, the coating can protect the metal surface of the pipeline, prolonging the service life of the pipeline. The multifunctional coating exhibits excellent superhydrophobic properties, effectively reducing the adhesion and retention of liquids in the pipeline. This not only helps to reduce the formation and accumulation of hydrates, preventing pipeline blockage and pressure loss, but also improves the transportation efficiency of the pipeline.

[0055] (4) The multifunctional coating not only actively prevents the formation and blockage of hydrates, but also passively delays the growth and accumulation of hydrates. This significantly reduces the frequency of pipeline maintenance and cleaning, reduces related costs, and improves the overall reliability and economy of the pipeline system.

[0056] (5) The spin-coating-spraying process provides a simple, efficient, and low-cost method for coating preparation. This helps reduce production costs, improve production efficiency, and makes multifunctional coatings more competitive in industrial applications. Attached Figure Description

[0057] Figure 1 This is a schematic diagram of the structure of the multifunctional anti-adhesion coating prepared according to the present invention;

[0058] Figure 2 A scanning electron microscope image of the nanoparticles obtained during the preparation of the multifunctional anti-adhesion coating of this invention;

[0059] Figure 3 This is a schematic diagram of the metal-organic framework nanoparticle intercalation obtained during the preparation of the multifunctional anti-adhesion coating of the present invention.

[0060] Figure 4 The surface morphology of the multifunctional anti-adhesion coating prepared according to the present invention after spraying;

[0061] Figure 5 The image shows the wettability test results of the multifunctional anti-adhesion coating prepared according to the present invention.

[0062] Figure 6 Electrochemical impedance spectroscopy (EIS) of the multifunctional anti-adhesion coating prepared according to this invention;

[0063] Figure 7 The effect of a 1000-cycle abrasion resistance test on the wettability of the multifunctional anti-adhesion coating prepared according to the present invention is shown.

[0064] Figure 8 The adhesion test results of the multifunctional anti-adhesion coating prepared according to the present invention on simulated cyclopentane hydrate are shown.

[0065] Figure 9 This is a schematic diagram of the adhesion test setup. Detailed Implementation

[0066] This invention provides a method for preparing a multifunctional anti-adhesion coating, the main steps of which are as follows: First, a selected metal salt and organic ligand are dissolved in an organic solvent, and a stable MOF structure is formed by ultrasonic stirring; simultaneously, nanoparticles are prepared by hydrothermal reaction of a mixed nitrate solution under alkaline conditions; the prepared MOFs are intercalated and assembled with the nanoparticles, and then sprayed onto a pretreated steel substrate to form a multifunctional coating. This coating has corrosion resistance and anti-adhesion properties, and the simple process steps such as spin coating and spraying ensure the practicality and cost-effectiveness of the preparation method.

[0067] The present application provides an effective deep water oil and gas pipeline anti-blocking technology by designing and preparing a multifunctional anti-adhesion coating, which can ensure smooth transportation of the pipeline and improve the efficiency and safety of energy development. At the same time, the technology provides protection against particle erosion while meeting the mechanical stability required in complex multiphase pipeline systems. It has the advantages of simplicity, economy, environmental protection, etc., and has wide application prospect and market value. The technology can reduce the risk of hydrate adhesion and blockage, reduce energy consumption, and ensure the safe operation of the oil and gas pipeline under the premise of ensuring the safety and efficiency of pipeline transportation.

[0068] The present application will be described in detail below with specific examples.

[0069] Example 1

[0070] Step 1: Preparation of metal Cu organic framework

[0071] First, 0.4 g of copper acetate was dissolved in 50 mL of anhydrous ethanol, and 0.2 g of trimellitic acid was dissolved in 10 mL of deionized water. The two solutions were mixed and ultrasonically treated for 30 min to obtain a suspension. The suspension was then magnetically stirred at a fixed speed of 1000 r / min at a temperature of 50℃ for 5 h, and then washed with anhydrous ethanol at 5000 r / min for 3 times, and then dried in an oven at a temperature of 65℃ for 6 h to obtain a metal Cu organic framework (Cu-MOFs).

[0072] Step 2: Preparation of nano copper oxide particles

[0073] 0.15 mol of Cu(NO3)2·3H2O was dissolved in 100 mL of deionized water, and then N2 was introduced. The pH of the nitrate solution was adjusted to about 13 using a 0.45 mol / L NaOH solution. The mixture was magnetically stirred at a fixed stirring speed of 500 r / min for 1 h, and then the mixture was transferred to a hydrothermal reactor and reacted at a temperature of 100℃ for 12 h. After the reaction, the mixture was washed with deionized water at 5000 r / min until the pH of the solution was about 7. Then, the mixture was dried at 65℃ for 12 h.

[0074] Step 3: Preparation of metal organic framework intercalation

[0075] 0.2 g of Cu-MOFs was dissolved in 30 mL of dimethylformamide (DMF), and then 0.2 g of nano CuO particles and 200 μL of stearic acid (SA) solution were added. The mass concentration of the stearic acid solution was 8.5%. The mixture was stirred at room temperature at a speed of 500 r / min for 2 h, and then washed with deionized water at 5000 r / min for 3 times. After drying at 60℃, the mixture was ground with a mortar and sieved with a 100 mesh sieve to obtain a metal organic framework intercalation (Cu-MOFs@CuO).

[0076] Step 4: Pretreatment of steel sheet substrate

[0077] The X65 steel sheet was polished sequentially with 280-grit, 320-grit, 400-grit, 600-grit, 800-grit, and 1000-grit SiC sandpaper. After ultrasonic cleaning with petroleum ether and anhydrous ethanol in sequence, it was dried in a N2 atmosphere for later use.

[0078] Step 5: Prepare the base layer

[0079] Polyacrylic resin and polyisocyanate were mixed in a mass ratio of 1:2, and then the mixture was spin-coated at 1500 r / min for 30 s. After being placed in an oven at 50 ℃ for 10 min, an incompletely cured base layer was obtained.

[0080] Step 6: Coating Assembly

[0081] 0.2 g of Cu-MOFs@CuO particles obtained in step 3 were dissolved in continuous phase ethanol. A spray gun was used with the air pressure adjusted to 0.5 MPa, the gun height to 20 cm, and the atomization value to 1.0 revolution to prepare for the spraying operation. The solution was sprayed onto the uncured substrate layer from step 5, and then the sample was allowed to cure naturally at room temperature for 24 h to obtain a multifunctional anti-adhesion coating.

[0082] Example 2

[0083] Step 1: Preparation of the metal Zn organic framework

[0084] First, 0.4 g of zinc acetate was dissolved in 50 mL of anhydrous ethanol at room temperature, and 0.2 g of terephthalic acid was dissolved in 10 mL of deionized water. The two solutions were mixed and sonicated for 30 min to obtain a suspension. The suspension was then magnetically stirred at a constant speed of 1000 r / min for 6 h at 60 °C, washed three times by centrifugation with anhydrous ethanol at 5000 r / min, and dried in an oven at 65 °C for 6 h to obtain metal-Zn organic frameworks (Zn-MOFs).

[0085] Step 2: Preparation of nano-zinc oxide particles

[0086] 0.15 mol of Zn(NO3)2·6H2O was dissolved in 100 mL of deionized water, and then N2 was bubbled through. The pH of the nitrate solution was adjusted to approximately 13 using a 0.45 mol / L NaOH solution. The mixture was magnetically stirred at a constant speed of 600 rpm for 1 h. The resulting substrate solution was then transferred to a hydrothermal reactor and reacted at 90 °C for 24 h. After the reaction, the solution was washed with deionized water at 6000 rpm until the pH reached approximately 7. Finally, the solution was dried at 65 °C for 12 h.

[0087] Step 3: Preparation of metal organic framework intercalation

[0088] Dissolve 0.2 g of Zn-MOFs in 30 mL of dimethyl sulfoxide (DMSO), then add 0.2 g of nano ZnO particles, 300 μL of 1H,2H,2H-perfluorodecyltrimethoxysilane solution. Stir at 500 r / min at room temperature for 2 h, then wash with deionized water at 5000 r / min for 3 times, dry at 60 °C, then grind with a mortar and sieve with a 100 mesh sieve to obtain metal organic framework intercalation (Zn-MOFs@ZnO).

[0089] Step 4: Pretreatment of steel sheet substrate

[0090] Grind the X65 steel sheet with 280 mesh, 320 mesh, 400 mesh, 600 mesh, 800 mesh, and 1000 mesh SiC sandpaper in order, then ultrasonically clean with petroleum ether and anhydrous ethanol in order, and dry under N2 atmosphere for standby use.

[0091] Step 5: Preparation of substrate layer

[0092] Mix polyurethane and polycaprolactam alcohol in a mass ratio of 1:3, then spin coat at 2000 r / min for 20 s using a spin coater, and then place in a 50 °C oven for 10 min to obtain an incompletely cured substrate layer.

[0093] Step 6: Assembly of coating

[0094] Dissolve 0.2 g of Zn-MOFs@ZnO particles obtained in step 3 in the continuous phase ethanol, and prepare for spraying operation using an airbrush with air pressure adjusted to 0.3 MPa, airbrush height of 15 cm, and atomization value of 1.2 turns. Spray the solution to be sprayed on the incompletely cured substrate layer of step 5, then place the sample at room temperature for natural curing for 24 h to prepare a multifunctional anti-adhesion coating.

[0095] Example 3

[0096] Step 1: Preparation of metal Cu organic framework

[0097] First, dissolve 0.4 g of copper acetate in 50 mL of anhydrous ethanol at room temperature, dissolve 0.2 g of trimellitic acid in 10 mL of deionized water, mix the two solutions and ultrasonically treat for 30 min to obtain a suspension. Then, magnetically stir the suspension at a fixed speed of 1000 r / min at a temperature of 50 °C for 5 h, then centrifuge and wash with anhydrous ethanol at 5000 r / min for 3 times, and then dry in an oven at a temperature of 65 °C for 6 h to obtain a metal Cu organic framework (Cu-MOFs).

[0098] Step 2: Preparation of nano cerium oxide particles

[0099] Dissolve 0.20 mol of Ce(NO3)3·6H2O in 100 mL of deionized water, then pass N2, and use a 0.45 mol / L NaOH solution to adjust the pH of the nitrate solution to about 13. First ultrasonic treatment for 10 min, then magnetic stirring at a fixed stirring speed of 500 r / min for 1 h, move the mixed substrate solution into the hydrothermal reactor, react at a temperature of 100°C for 12 h, and then wash with deionized water at 5000 r / min until the solution pH is about 7. Then dry at 65°C for 12 h.

[0100] Step 3: Preparation of metal organic framework intercalation

[0101] Dissolve 0.2 g of Cu-MOFs in 30 mL of dimethylformamide (DMF), then add 0.2 g of nano CeO2 particles, 200 μL of H,1H,2H,2H-perfluorodecyltriethoxysilane solution, and the mass concentration of the silane solution is 10%. Stir at room temperature for 2 h at a speed of 500 r / min, then wash with deionized water 3 times at 5000 r / min, dry at 60°C, then grind with a mortar and sieve with a 100 mesh sieve to obtain metal organic framework intercalation (Cu-MOFs@CeO2).

[0102] Step 4: Pretreatment of steel sheet substrate

[0103] Grind the X65 steel sheet with 280 mesh, 320 mesh, 400 mesh, 600 mesh, 800 mesh, and 1000 mesh SiC sandpaper in order, then ultrasonically clean with petroleum ether and anhydrous ethanol in order, and then dry under N2 atmosphere for standby use.

[0104] Step 5: Preparation of base layer

[0105] Mix the epoxy resin and oxirane amine in a mass ratio of 1:1.5, then spin coat at 1500 r / min for 30 s using a spin coater, and then place in a 50°C oven for 10 min to obtain an incompletely cured base layer.

[0106] Step 6: Assembly of coating

[0107] Dissolve 0.2 g of Cu-MOFs@CeO2 particles obtained in step 3 in the continuous phase ethanol, and prepare for spraying operation using an airbrush with an air pressure of 0.6 MPa, a spraying height of 20 cm, and an atomization value of 1.0 turn. Spray the solution to be sprayed on the uncured base layer of step 5, then place the sample at room temperature for natural curing for 24 h to prepare a multifunctional anti-adhesion coating.

[0108] Example 4

[0109] Step 1: Preparation of metal Ni organic framework

[0110] Firstly, 0.3 g of nickel acetate was dissolved in 50 mL of absolute ethanol at room temperature, and 0.3 g of benzene tetraacid was dissolved in 10 mL of deionized water. After ultrasonic treatment for 20 min, the two solutions were mixed to obtain a suspension. Then the suspension was stirred at a fixed speed of 800 r / min at a temperature of 40 °C for 6 h, and then washed with absolute ethanol at 5500 r / min for 3 times. After drying in an oven at a temperature of 70 °C for 5 h, the metal Cu organic framework (Ni-MOFs) was obtained.

[0111] Step 2: Preparation of nano cerium oxide particles

[0112] 0.20 mol of Ce(NO3)3·6H2O was dissolved in 100 mL of deionized water, and then N2 was introduced. The pH of the nitrate solution was adjusted to about 13 using a 0.45 mol / L NaOH solution. The mixed substrate solution was moved into a hydrothermal reactor and reacted at a temperature of 100 °C for 12 h under magnetic stirring at a fixed stirring speed of 500 r / min. After the reaction, the solution was washed with deionized water at 5000 r / min until the pH was about 7. Then, it was dried at 65 °C for 12 h.

[0113] Step 3: Preparation of metal organic framework intercalation

[0114] 0.3 g of Ni-MOFs was dissolved in 30 mL of dimethylformamide (DMF), and then 0.1 g of nano CeO2 particles, 200 μL of trichloro(1H,1H,2H,2H-perfluorooctyl)silane solution were added. After stirring at room temperature for 1 h at a speed of 500 r / min, the product was washed with deionized water at 5000 r / min for 3 times, and then dried at 65 °C. After grinding with a mortar and sieving with a 100 mesh sieve, the metal organic framework intercalation (Ni-MOFs@CeO2) was obtained.

[0115] Step 4: Pretreatment of steel sheet substrate

[0116] The X65 steel sheet was polished with 280 mesh, 320 mesh, 400 mesh, 600 mesh, 800 mesh, and 1000 mesh SiC sandpaper, and then ultrasonically cleaned with petroleum ether and absolute ethanol in sequence. After drying under N2 atmosphere, it was ready for use.

[0117] Step 5: Preparation of base layer

[0118] Polyurethane and polycaprolactam alcohol were mixed in a mass ratio of 1:3, and then spin-coated at 1500 r / min for 30 s using a spin coater. After being placed in an oven at 50 °C for 15 min, an incompletely cured base layer was obtained.

[0119] Step 6: Assembly of the coating

[0120] The Ni-MOFs@CeO2particles obtained in step 3 were dissolved in the continuous phase ethyl acetate, and a spray gun was used to prepare for the spraying operation with an air pressure of 0.5 MPa, a spray gun height of 15 cm, and an atomization value of 1.0 circle. The solution to be sprayed was sprayed on the uncured base layer of step 5, and then the sample was naturally cured at room temperature for 24 h to prepare a multifunctional anti-adhesion coating.

[0121] Figure 1 A schematic diagram of the multifunctional anti-adhesion coating prepared in Example 1 of the present application is shown in the figure, which shows the overall structure of the anti-adhesion coating. As shown in Figure 1 , the bottom is a metal substrate, the middle base layer is a polyacrylate, which protects and buffers the metal substrate, and the outermost layer is a metal organic framework (MOFs) structure loaded with CuO nanoparticles.

[0122] Figure 2 A scanning electron microscope image of the nanoparticles obtained during the preparation of a multifunctional anti-adhesion coating according to the present application is shown in Figure 2 , which clearly shows that the CuO nanoparticles prepared by the urea hydrothermal method are spherical and agglomerated together, with a size of about 100 nm.

[0123] Figure 3 A schematic diagram of the metal organic framework nanoparticles intercalated during the preparation of a multifunctional anti-adhesion coating according to the present application is shown in Figure 3 , the metal organic framework CuO nanoparticles intercalated (Cu-MOFs@CuO) prepared by the immersion method can effectively disperse the CuO nanoparticles, providing effective adsorption sites for the attachment and dispersion of nanoparticles.

[0124] Figure 4 The surface morphology of a multifunctional anti-adhesion coating prepared according to the present application after spraying, in which polyacrylate was coated on the surface of X65 steel by spin coating, and then the uncured base layer was sprayed with metal organic framework CuO nanoparticle intercalation (Cu-MOFs@CuO), is shown in Figure 4 , the surface forms a micro-nano structure containing nanoparticles and a continuous phase of polyacrylate, which is more conducive to the formation of a super-hydrophobic surface.

[0125] Figure 5 A wettability detection and evaluation result graph of a multifunctional anti-adhesion coating prepared according to the present application is shown in Figure 5As shown, the contact angle values of the four types of coatings in Example 1, Example 2, Example 3, and Example 4 of the present application were measured by a contact angle measuring instrument using a fixed drop suspension method (the test liquid was deionized water), and were 154.4°, 155.9°, 156.6°, and 153.9°, respectively. The hydrophobic effect of Example 3 was the best.

[0126] Figure 6 In order to quantitatively evaluate the corrosion resistance of the composite coating, electrochemical impedance spectroscopy (EIS) tests were performed on the four types of coatings in Example 1, Example 2, Example 3, and Example 4 of the present application after being immersed in a 3.5wt% NaCl solution for 24h. The results of EIS showed that the transfer resistance R p of Example 1, Example 2, Example 3, and Example 4 was 1.66×10 6 Ω / cm 2 , 1.77×10 6 Ω / cm 2 , 1.97×10 6 Ω / cm 2 , and 1.88×10 6 Ω / cm 2 , respectively. The transfer resistance R p of the X65 carbon steel was only 2610Ω / cm 2 . The capacitive arc radius of the X65 carbon steel with the added coating was larger than that of the single X65 carbon steel, which indicated that the addition of the coating greatly inhibited the occurrence of corrosion. The corrosion resistance of Example 3 was the best.

[0127] Figure 7 The 1000-cycle wear resistance test of the multifunctional anti-adhesion coating prepared by the present application affected the wettability of the coating. The contact angle of Example 3 was measured after different wear cycles of 200, 400, 600, 800, and 1000 times using a wear tester. After 1000 cycles of friction, the contact angle decreased from 164.3° to 151.8°, and the sliding angle increased from 6.9° to 8.8°. The coating was still a super-hydrophobic coating.

[0128] Figure 8 The multifunctional anti-adhesion coating prepared by the present application was subjected to an adhesion test of simulated generated cyclopentane hydrates, Figure 9 which is a schematic diagram of an adhesion test device; in the figure: 1-mechanical operating arm, 2-glass fiber, 3-steel sheet with coating, 4-quartz square box, 5-cyclopentane solution, 6-hydrate.

[0129] A piece of bare steel X65 and the anti-adhesion coating of Example 3 were placed in a quartz square cell filled with cyclopentane, then the system temperature was lowered to -4°C and held at this temperature for 30 min. Then, a small drop of liquid water (2 μΐ) was carefully dropped on the square wall material immersed in cyclopentane. To give the drop enough time to fully form hydrate particles, the temperature was gradually increased to 1 °C. When the hydrates were formed, the tip of a glass fiber was fixed on a hand-held stage and the glass fiber was used to push the hydrate particles by applying a force with a micromechanical force arm until they detached from the wall material surface. The displacement of the glass fiber was recorded using a microscope and the adhesion force of the hydrate particles on the X65 and coated surfaces was calculated. As shown in Figure 8 Figure 9, the hydrates on the bare steel X65 surface could not be removed when a force of 0.1 mN / m was applied, resulting in the breaking of the hydrate shell. In contrast, the surface of the Example 3 coating allowed the hydrate particles to swing with the movement of the small glass fiber when the average adhesion force was increased to 0.0064 mN / m.

Claims

1. A method for the production of multifunctional anti-adhesive coatings, characterized in that The method comprises the following steps: (1) preparing a metal organic framework Dissolve a metal salt in an organic solvent to obtain a metal salt solution; dissolve an organic ligand in deionized water to obtain an organic ligand solution; then mix the metal salt solution and the organic ligand solution to perform a reaction to obtain a reaction liquid one; and centrifugally wash and dry the reaction liquid one to obtain the metal organic framework; (2) preparing nanoparticles Add a nitrate salt to deionized water to obtain a nitrate salt solution, then add an alkaline solution to the nitrate salt solution to adjust a pH value to obtain a substrate solution; Move the substrate solution into a hydrothermal reaction kettle to perform a reaction to obtain a reaction liquid two, and centrifugally wash and dry the reaction liquid two to obtain the nanoparticles; (3) preparing a metal organic framework intercalation Dissolve the metal organic framework in the step (1) in an organic solvent to obtain a metal organic framework solution; add the nanoparticles in the step (2) to the metal organic framework solution, and then add a modification solution to perform a stirring reaction; and after the reaction is completed, centrifugally wash and dry the metal organic framework intercalation to obtain the metal organic framework intercalation; (4) pretreating a steel sheet substrate Grind the steel sheet substrate using sandpaper, and then ultrasonically clean and dry the steel sheet substrate under a N2 atmosphere for standby use; (5) preparing a base layer On the steel sheet substrate pretreated in the step (4), select a buffer coating and a curing agent, perform a spin coating through a spin coater, and then perform heating to form an uncured base layer; (6) assembling a coating Dissolve the metal organic framework intercalation obtained in the step (3) in a continuous phase, then spray the metal organic framework intercalation onto the uncured base layer in the step (5), and then place the uncured base layer in a room temperature environment to naturally solidify to obtain a multifunctional anti-adhesion coating; In the step (1), the metal salt is copper acetate, zinc acetate, aluminum acetate or nickel acetate; the organic solvent is ethanol, dimethylformamide or dimethyl sulfoxide; and the organic ligand is trimellitic acid, terephthalic acid or mellitic acid; The concentration of the metal salt solution is 1.5-2.0 mol / L, the mass concentration of the organic ligand solution is 92%-95%, and the molar ratio of the metal salt to the organic ligand is 1:5-1:6; In the step (2), the nitrate salt is cerium nitrate, copper nitrate or zinc nitrate, and the concentration of the nitrate salt solution is 1.5-2.0 mol / L; The alkaline solution is a NaOH solution, and the concentration of the NaOH solution is 0.40-0.45 mol / L; When the alkaline solution is added to the nitrate salt solution to adjust the pH value, N2 is introduced; The pH value is adjusted to 12-14; In the step (3), the organic solvent is methanol, dimethylformamide or dimethyl sulfoxide; and the modification solution is a stearic acid solution, a 1H, 2H, 2H-perfluorodecyltrimethoxysilane solution, a 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane solution or a trichloro(1H, 1H, 2H, 2H-perfluorooctyl)silane solution; 0.2-0.4 g of the metal organic framework is dissolved in 30-50 mL of the organic solvent; the addition amount of the nanoparticles is 0.1-0.2 g; and the addition amount of the modification solution is 200-300 μL; and the mass concentration of the modification solution is 8.5%-10%; The stirring temperature is controlled at 25-30℃, the stirring speed is controlled at 500-600r / min, and the stirring time is controlled at 1-2h; After the reaction, centrifugal washing is performed 3-5 times using deionized water; the drying temperature is controlled at 50-60℃, the dried particles are ground into powder using a mortar and sieved using a 100-mesh screen, and the metal-organic framework intercalation is obtained.

2. A method of preparing a multifunctional anti-adhesion coating according to claim 1, characterized in that, In step (1), the metal salt solution and the organic ligand solution are mixed and then subjected to ultrasonic treatment; the ultrasonic treatment time is controlled at 20-30min; Then, stirring reaction is performed; the stirring speed is controlled at 800-1000r / min, the reaction temperature is controlled at 45-60℃, and the reaction time is controlled at 5-6h; After the reaction, centrifugal washing is performed 3-5 times using anhydrous ethanol; the centrifugal speed is controlled at 5000-6000r / min, and the drying temperature is controlled at 65-70℃, and the drying time is controlled at 5-6h.

3. A method of preparing a multifunctional anti-adhesion coating according to claim 1, characterized in that, In step (2), the substrate solution is stirred before being transferred into the hydrothermal reactor; the stirring temperature is controlled at 25-30℃, the stirring speed is controlled at 500-600r / min, and the stirring time is controlled at 1-2h; The reaction temperature in the hydrothermal reactor is controlled at 90-100℃, and the reaction time is controlled at 12-24h; After the reaction, centrifugal washing is performed using deionized water until the pH value of the reaction solution is 7; The drying temperature is controlled at 65-70℃.

4. The method of claim 1, wherein the method further comprises: In step (4), the steel sheet substrate is selected from one of X65 steel, X80 steel, and L245 steel; the sandpaper is selected from 280-mesh, 320-mesh, 400-mesh, 600-mesh, 800-mesh, and 1000-mesh SiC sandpaper; and petroleum ether and anhydrous ethanol are used in sequence during the ultrasonic cleaning process.

5. The method of claim 1, wherein the multifunctional anti-adhesion coating is prepared by, In step (5), the buffer coating is selected from polyacrylic resin, polyurethane, or epoxy resin; the curing agent is selected from polyisocyanate, polyhexamethylene lactam alcohol, or oxirane amine; and the mass ratio of the curing agent to the buffer coating is 1:1.5-1:3; The rotation speed of the spin coater is controlled at 1300-2000r / min, the spin coating time is controlled at 20-30s, the heating temperature is controlled at 50-60℃, and the heating time is controlled at 10-15min.

6. The method of claim 1, wherein the multifunctional anti-adhesion coating is prepared by, In step (6), the continuous phase is anhydrous ethanol or ethyl acetate; The spraying parameters are as follows: the air pressure is 0.3-0.5MPa, the spray gun height is 15-20cm, and the atomization value is 1.0-1.5 turns.

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