A fluorocarbon resin-based composite super-slip coating and a preparation method thereof

Abstract

The present invention discloses a fluorocarbon resin-based composite super-slippery coating and a preparation method thereof, belonging to the technical field of anti-corrosion and anti-fouling coatings. Aiming at the problems of poor stability of the oil layer on the super-slippery surface and insufficient realizability of the super-slippery function, the present invention prepares a fluorocarbon resin-based composite super-slippery coating with good corrosion resistance and anti-scaling performance. Through in-situ hybridization of SiO2, thermal decomposition of urea and embedded CNTs, the present invention jointly constructs a hierarchical porous structure with a covalent interpenetrating network, significantly improving the interfacial interaction inside the coating and enhancing the mechanical durability of the coating. The anchoring mechanism of the lubricating oil is revealed by molecular dynamics simulation and Hückel rule calculation. Due to the highly stable oil layer, the coating exhibits excellent ultraviolet durability, thermal stability and underwater stability, and provides new ideas for the design of durable super-slippery coatings.

Description

Technical Field

[0001] The invention relates to the technical field of anti-corrosion and anti-fouling coatings, and in particular to a fluorocarbon resin-based composite super-slip coating and a preparation method thereof. Background Art

[0002] A slippery liquid-infused porous surface, or SLIPS for short, has attracted considerable attention in anti-corrosion, anti-fouling, and anti-fouling applications due to its excellent water repellency and extremely low sliding angle.

[0003] Many methods for designing and preparing SLIPS coatings have been proposed in the prior art. SLIPS coatings can be divided into three types according to the preparation method: one-dimensional SLIPS, in which lubricant molecules are chemically grafted onto the substrate surface; two-dimensional SLIPS, including the preparation of porous structures, low surface energy modification, and lubricant injection; and three-dimensional SLIPS with a cross-linked gel polymer network. Yao et al. synthesized in-situ MgAl layered double hydroxides with nanoporous structures on AZ31Mg alloy using a hydrothermal method, and then obtained a SLIPS coating with long-term corrosion protection by adding sodium benzoate inhibitor and injecting lubricants. Guo et al. used hydroxyapatite nanowires as a substance to enhance biocompatibility and food safety, and also as an oil-locking layer after spraying to construct a three-dimensional network structure, which was used in the construction of SLIPS. Xu et al. used titanium sheets as working electrodes and graphene sheets as reference electrodes. After two-step anodization, a nanoporous structure was obtained. SLIPS was obtained by low surface energy modification and perfluoropolyether oil injection.

[0004] Although these structural designs allow for the storage of large amounts of lubricants, the excessively porous structures prepared by adding abundant nanoparticles may weaken the crosslinking of the resin, thereby compromising the mechanical stability of the SLIPS coating. Therefore, it is difficult to balance mechanical stability and surface oil layer stability by simply absorbing lubricants through a porous structure, resulting in poor oil layer stability and insufficient feasibility of super-slippery functions in conventional super-slippery coatings. Summary of the invention

[0005] In view of the above problems, the present invention provides a fluorocarbon resin-based composite super-slip coating and a preparation method thereof, which effectively solves the technical problems of poor oil layer stability and insufficient feasibility of super-slip function of traditional super-slip coatings. 2 In-situ hybridization and embedded carbon nanotubes jointly construct a hierarchical porous structure with a covalent interpenetrating network, which promotes the infiltration of lubricating oil into the coating. Through interfacial covalent bonds and π-OH interactions, chemical bridge methylene diphenyl diisocyanate anchors the oil layer to the coating surface, significantly improving the anti-corrosion performance of the fluorocarbon resin-based composite super-slip coating. The present invention constructs a fluorocarbon resin-based composite super-slip coating that combines high oil layer stability and excellent super-slip performance.

[0006] The first object of the present invention is to provide a method for preparing a fluorocarbon resin-based composite super-slip coating, comprising the following steps:

[0007] Carboxyl carbon nanotubes are subjected to hydrophobic and lipophilic modification to obtain modified carbon nanotube particles.

[0008] Fluorinated ethylene-(hydroxy-alkyl) vinyl ether and curing agent are used as coating raw materials, and ethyl orthosilicate and ammonia are added to generate SiO 2 , get SiO 2 The fluorocarbon resin-based solution is loaded, urea, a hydrophobic lipophilic modifier and the modified carbon nanotube particles are added, ultrasonication is performed to obtain a coating solution, the coating solution is sprayed at 48°C to 60°C to obtain a wet coating, and the coating is cured at 150°C to 240°C. The fluorinated ethylene-(hydroxy-alkyl) vinyl ether and the curing agent are cross-linked and bonded to the SiO 2 Cross-linking and hybridization are carried out, and urea is pyrolyzed to generate pores to obtain loaded SiO 2 / CNTs fluorocarbon resin-based superhydrophobic coating.

[0009] The solution containing isocyanate groups is sprayed onto the supported SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating is formed to obtain a modified coating, hydroxyl fluorosilicone oil is dropped onto the surface of the modified coating, placed in a vacuum, and reacted at 180°C to 240°C, so that the isocyanate group and the hydroxyl fluorosilicone oil undergo an addition reaction to obtain a fluorocarbon resin-based composite super-slip coating.

[0010] As a preferred embodiment, the usage ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to tetraethyl orthosilicate is 1 g:0.3 mL~0.4 mL, the concentration of the ammonia water is 25%, and the volume ratio of the tetraethyl orthosilicate to the ammonia water is 1:0.8~1.2.

[0011] As a preferred embodiment, the mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to the carbon nanotube particles is 2:0.09-0.11.

[0012] As a preferred embodiment, the mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to urea is 2:0.08-0.13.

[0013] As a preferred embodiment, the solution containing isocyanate groups is an ethyl acetate solution of methylene diphenyl diisocyanate, and the mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to methylene diphenyl diisocyanate is 2:0.1-0.2.

[0014] As a preferred embodiment, the mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to the hydroxyfluorosilicone oil is 2:1-2.

[0015] As a preferred embodiment, the preparation method of the modified carbon nanotube particles is specifically as follows: adding perfluorooctyltrichlorosilane to an ethanol solution of carboxyl carbon nanotubes in a stirring state, reacting, drying, and grinding to obtain modified carbon nanotube particles.

[0016] As a preferred embodiment, the usage ratio of the carboxyl carbon nanotubes to perfluorooctyltrichlorosilane is 0.7 g: 10 μL~20 μL.

[0017] As a preferred embodiment, the hydrophobic-lipophilic modifier is perfluorooctyltrichlorosilane, and the usage ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to perfluorooctyltrichlorosilane is 1 g: 0.8 μL~1.5 μL.

[0018] As a preferred embodiment, after hydroxyfluorosilicone oil is dropped onto the surface of the modified coating, it is placed under a vacuum condition of 0.06MPa-0.08MPa for 2h.

[0019] The second object of the present invention is to provide a fluorocarbon resin-based composite super-slip coating prepared by the above preparation method.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The present invention provides a method for preparing a fluorocarbon resin-based composite super-slip coating. Aiming at the problems of poor stability of the super-slip surface oil layer and insufficient feasibility of the super-slip function, the present invention prepares a fluorocarbon resin-based composite super-slip coating with good corrosion resistance and anti-scaling performance, which is denoted as FEVE-SiO 2 / CNTs@MDI SLIPS coating. The present invention firstly performs hydrophobic and lipophilic modification on carboxyl carbon nanotubes to obtain modified carbon nanotube particles; then, fluorinated ethylene-(hydroxy-alkyl) vinyl ether and a curing agent are used as coating raw materials, and tetraethyl orthosilicate and ammonia are added to generate SiO 2 , get SiO 2 The fluorocarbon resin-based solution is loaded, urea, a hydrophobic lipophilic modifier and the modified carbon nanotube particles are added, and the modified carbon nanotube particles are cross-linked with fluorinated ethylene-(hydroxy-alkyl) vinyl ether and a curing agent and bonded to SiO 2 Cross-linking and hybridization are carried out, and urea is pyrolyzed to generate pores to obtain loaded SiO 2 / CNTs fluorocarbon resin-based super hydrophobic coating; spraying a solution containing isocyanate groups onto the loaded SiO 2 / CNTs fluorocarbon resin-based super hydrophobic coating to obtain a modified coating, hydroxy fluorosilicone oil is added dropwise to the surface of the modified coating, and the isocyanate group reacts with the hydroxy fluorosilicone oil to obtain a fluorocarbon resin-based composite super slippery coating. 2 In situ hybridization, urea thermal decomposition, and embedded CNTs jointly constructed a hierarchical porous structure with a covalent interpenetrating network, which significantly improved the interfacial interaction within the coating and enhanced the mechanical durability of the coating.

[0022] The present invention uses molecular dynamics simulation and Hückel rule calculation to reveal the anchoring mechanism of lubricating oil. Due to the highly stable oil layer, the coating exhibits excellent UV durability, thermal stability, and underwater stability, and provides new ideas for designing durable super-slip coatings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a graph showing the influence of different contents of carbon nanotubes on the wettability of the fluorocarbon resin-based composite super-slip coating used in the present invention.

[0024] Figure 2 This is the impedance diagram of the fluorocarbon resin-based composite super-slip coating prepared in the present invention.

[0025] Figure 3 FEVE-SiO prepared in Example 1 of the present invention 2 / CNTs coating, FEVE-SiO 2 / CNTs@MDI SLIPS coating and FEVE-SiO prepared in Comparative Example 5 2 / CNTs SLIPS coating surface Ca content comparison bar chart.

[0026] Figure 4 The FEVE-SiO prepared in the present invention 2 Changes in water contact angle WCA and water sliding angle WSA of / CNTs@MDI SLIPS coating after immersion in water for 14 days. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solution of the present invention and implement it, the present invention is further described below in conjunction with specific examples, but the examples are not intended to limit the present invention. The following test methods and detection methods, unless otherwise specified, are conventional methods; the reagents and raw materials, unless otherwise specified, are commercially available.

[0028] In view of the technical problems that the traditional super-lubricating coating has poor oil layer stability and insufficient feasibility of super-lubricating function, the present invention provides a fluorocarbon resin-based composite super-lubricating coating and a preparation method thereof.

[0029] The technical solution of the present invention is described in detail below.

[0030] The present invention first provides a method for preparing a fluorocarbon resin-based composite super-slip coating, comprising the following steps:

[0031] Carboxyl carbon nanotubes are subjected to hydrophobic and lipophilic modification to obtain modified carbon nanotube particles.

[0032] Fluorinated ethylene-(hydroxy-alkyl) vinyl ether and curing agent are used as coating raw materials, and ethyl orthosilicate and ammonia are added to generate SiO 2 , get SiO 2 The fluorocarbon resin-based solution is loaded, urea, a hydrophobic lipophilic modifier and the modified carbon nanotube particles are added, ultrasonication is performed to obtain a coating solution, the coating solution is sprayed at 48°C to 60°C to obtain a wet coating, and the coating is cured at 150°C to 240°C. The fluorinated ethylene-(hydroxy-alkyl) vinyl ether and the curing agent are cross-linked and bonded to the SiO 2 Cross-linking and hybridization are carried out, and urea is pyrolyzed to generate pores to obtain loaded SiO 2 / CNTs fluorocarbon resin-based superhydrophobic coating.

[0033] The solution containing isocyanate groups is sprayed onto the supported SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating is formed to obtain a modified coating, hydroxyl fluorosilicone oil is dropped onto the surface of the modified coating, placed in a vacuum, and reacted at 180°C to 240°C, so that the isocyanate group and the hydroxyl fluorosilicone oil undergo an addition reaction to obtain a fluorocarbon resin-based composite super-slip coating.

[0034] In the above technical solution, ethyl orthosilicate undergoes hydrolysis reaction to generate SiO 2 , in situ cross-linking and curing with fluorinated ethylene-(hydroxy-alkyl) vinyl ether and curing agent, and then through the subsequent thermal decomposition of urea and embedded carbon nanotubes, a hierarchical porous structure with a covalent interpenetrating network was constructed, which significantly improved the interfacial interaction within the coating and enhanced the mechanical durability of the coating.

[0035] For the spraying temperature of 48℃~60℃, if the spraying temperature is too low, the solvent evaporates slowly below 48℃, which is easy to cause the solution to aggregate. At this time, the rough structure of the surface will weaken, affecting the super-hydrophobic properties of the surface. If the temperature is too high, above 60℃, the solvent evaporates too quickly, causing the coating surface structure to be too loose and the mechanical strength to be weakened. Therefore, it is necessary to ensure that the spraying is carried out under heating conditions and control the spraying temperature to 48℃~60℃.

[0036] For the curing temperature of 150°C to 240°C, if the temperature is lower than 150°C, the curing reaction cannot proceed. If the temperature is higher than 240°C, although the curing reaction can proceed, the cross-linking structure of the formed fluorocarbon resin is destroyed and super-hydrophobic properties cannot be achieved.

[0037] The addition reaction is carried out at 180°C ~ 240°C for 20 ~ 30 minutes. If the temperature is lower than 180°C, the reaction efficiency of the addition reaction is low and the performance of the composite coating is affected. If the temperature is higher than 240°C, the hydroxyfluorosilicone oil on the surface of the composite coating begins to decompose and super-slip and super-hydrophobic properties cannot be achieved.

[0038] In order to improve the SiO 2 The loading amount ensures the super-hydrophobic property of the composite coating, the dosage ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to tetraethyl orthosilicate is 1g:0.3mL~0.4mL, the concentration of the ammonia water is 25%, and the volume ratio of the tetraethyl orthosilicate to the ammonia water is 1:0.8~1.2.

[0039] In order to further improve the super-hydrophobic and super-oleophilic properties of the composite coating, the mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to the carbon nanotube particles is 2:0.09-0.11. If the content of the modified carbon nanotube particles is less than 0.09, it will affect the construction of the structure and fail to achieve super-hydrophobic properties. If the content exceeds 0.11, the addition of too many inorganic particles will reduce the adhesion between the coating and the substrate. It will also excessively reduce the surface free energy of the coating, affecting the super-oleophilic properties.

[0040] In order to make the composite coating achieve excellent super-hydrophobicity and have better mechanical durability, the mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to urea is 2:0.08~0.13. Urea, as a pore-forming agent, plays a role in constructing a stable pore structure. The pore volume is very important for lubricating oil penetration. Too few pores are not enough to store a large amount of lubricating oil, which will affect the oil lock effect. And too much pore structure will reduce the mechanical durability of the coating. If the urea content is less than 0.08 defined herein, the pore structure becomes less, affecting the penetration of the lubricating oil. If the urea content is greater than 0.13 defined herein, the scale of the coating pore structure is too large, resulting in the coating surface structure being too loose, affecting the mechanical durability of the super-hydrophobic substrate.

[0041] It should be noted that the solution containing isocyanate groups is an ethyl acetate solution of methylene diphenyl diisocyanate, and the mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to methylene diphenyl diisocyanate is 2:0.1~0.2. When the methylene diphenyl diisocyanate is less than 0.1 as defined herein, the reaction sites formed by methylene diphenyl diisocyanate on the coating surface are relatively few, and it is difficult to fully ensure the stable anchoring of the hydroxyfluorosilicone oil. When the methylene diphenyl diisocyanate is greater than 0.2 as defined herein, the amount of methylene diphenyl diisocyanate used is too much, which will form an accumulation of methylene diphenyl diisocyanate, weaken the bridging effect, and weaken the stability of the hydroxyfluorosilicone oil.

[0042] In order to ensure the super-lubricating properties of the composite coating and the stability of the surface oil layer, the mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to the hydroxyfluorosilicone oil is 2:1~2. As an inert silicone oil, the amount of hydroxyfluorosilicone oil is very critical for the construction of the super-lubricating coating. If the content of hydroxyfluorosilicone oil is too little, it cannot ensure that the super-hydrophobic substrate is completely infiltrated with lubricating oil, affecting the super-lubricating performance. If the content of hydroxyfluorosilicone oil is too much, the oil film on the surface of the super-lubricating coating will be too thick, affecting the sliding performance and the stability of the surface oil layer.

[0043] It should be noted that the preparation method of the modified carbon nanotube particles is specifically as follows: adding perfluorooctyltrichlorosilane to an ethanol solution of carboxyl carbon nanotubes in a stirring state, reacting, drying, and grinding to obtain modified carbon nanotube particles.

[0044] In order to balance the super-hydrophobic and super-oleophilic properties of the composite coating, the amount ratio of the carboxyl carbon nanotube to perfluorooctyl trichlorosilane is 0.7g:10μL~20μL. If the carbon nanotube fluorination modification degree is low, the super-hydrophobicity of the coating is affected. If the carbon nanotube fluorination modification degree is too high, the surface free energy of the coating will be excessively reduced, which is not conducive to achieving super-oleophilic performance. In addition, the introduction of a large amount of fluorine elements will reduce the covalent bond density of the system, affecting the adhesion of the coating and the metal substrate.

[0045] As a preferred embodiment, the hydrophobic lipophilic modifier is perfluorooctyl trichlorosilane, and the amount ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to perfluorooctyl trichlorohydrosilane is 1g:0.8μL~1.5μL. In the coating preparation process, an appropriate amount of trichlorofluorosilane can ensure that a uniform and dense low surface energy layer is formed on the coating surface, thereby improving the hydrophobic properties of the coating. When the content of trichlorofluorosilane is too low, the low surface energy layer on the coating surface may not be complete, resulting in a decrease in hydrophobic properties; when the content is too high, the surface free energy of the coating may be too low, affecting the super oleophilic effect, and may cause the internal stress of the coating to increase, increasing the risk of cracking or falling off of the coating. In addition, if it is not added, the surface free energy of the coating will not reach the critical value for achieving super hydrophobic properties, which will affect the super hydrophobic properties of the coating.

[0046] It should be emphasized that after the hydroxyfluorosilicone oil is dropped onto the surface of the modified coating, it is placed under a vacuum condition of 0.06MPa~0.08MPa for 2h.

[0047] The present invention is specifically described below by means of the following examples and comparative examples.

[0048] Example 1

[0049] A fluorocarbon resin-based composite super-slip coating and a preparation method thereof, comprising the following steps:

[0050] S1, preparation of modified carbon nanotube particles: 0.7 g of carboxyl carbon nanotubes were dispersed in 40 mL of ethanol, then added to 10 μL of perfluorooctyltrichlorosilane under stirring for 4 h, dried at 80° C. for 12 h, and ground to obtain modified carbon nanotube particles.

[0051] S2, preparation of loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating: 2 g of fluorinated ethylene-(hydroxy-alkyl) vinyl ether and 0.1 g of curing agent N3390 were fully dispersed in a beaker filled with 15 mL of ethyl acetate, and ultrasonicated for 10 min to obtain a first mixture. 0.7 mL of tetraethyl orthosilicate was transferred to a beaker filled with 5 mL of ethanol with a dropper and stirred thoroughly. The ethanol solution of tetraethyl orthosilicate was added dropwise to the mixture. Then, 0.7 mL of 25% ammonia solution was added to the mixture and magnetically stirred for 30 min to obtain a second mixture. 0.1 100 g urea was added into 0.5 mL deionized water, and stirred continuously for 5 min until the urea was completely dissolved to obtain a urea solution. The urea solution was added into the second mixture, and 2 μL perfluorooctyltrichlorosilane was slowly added dropwise, and stirred for 0.5 h. Then, 0.1 g modified carbon nanotube particles were added, and a cell crusher was used for ultrasonication for 5 min to obtain a coating solution. The coating solution was sprayed onto the surface of the aluminum substrate at 50 ° C and a distance of 15 cm, and cured at 180 ° C to obtain a SiO2-loaded carbon nanotube. 2 / CNTs fluorocarbon resin-based super hydrophobic coating, denoted as FEVE-SiO 2 / CNTs superhydrophobic coating.

[0052] S3, preparing a fluorocarbon resin-based composite super-slip coating: 0.15 g of methylene diphenyl diisocyanate was dissolved in 5 mL of ethyl acetate and sprayed onto the FEVE-SiO 2 / CNTs super-hydrophobic coating was heated at 80 °C for 10 min to completely evaporate the solvent, and 1.5 g of hydroxy fluorosilicone oil was added dropwise to the FEVE-SiO 2 The surface of the super-hydrophobic coating of / CNTs was then placed in a vacuum drying oven and placed under a pressure of 0.08 MPa for 2 h to allow the hydroxyl fluorosilicone oil to fill the pores. The coating was then heated in an oven at 180 °C for 30 min to obtain a fluorocarbon resin-based composite super-slip coating, which was recorded as FEVE-SiO 2 / CNTs@MDI SLIPS coating.

[0053] Example 2

[0054] A fluorocarbon resin-based composite super-slip coating and a preparation method thereof, comprising the following steps:

[0055] S1, preparing modified carbon nanotube particles: 0.7 g of carboxyl carbon nanotubes were dispersed in 40 mL of ethanol, then added to 20 μL of perfluorooctyltrichlorosilane under stirring for 4 h, dried at 80° C. for 12 h, and ground to obtain modified carbon nanotube particles.

[0056] S2, preparation of loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating: 2 g of fluorinated ethylene-(hydroxy-alkyl) vinyl ether and 0.1 g of curing agent N3390 were fully dispersed in a beaker containing 15 mL of ethyl acetate, and ultrasonicated for 10 min to obtain a first mixture. 0.6 mL of tetraethyl orthosilicate was transferred to a beaker containing 5 mL of ethanol with a dropper and stirred thoroughly. The ethanol solution of tetraethyl orthosilicate was added dropwise to the mixture. Then, 0.6 mL of tetraethyl orthosilicate was added to the mixture. 25% ammonia solution, and magnetically stirred for 30 minutes to obtain a second mixture, 0.08g urea was added to 0.5mL deionized water, and stirred continuously for 5 minutes until the urea was completely dissolved to obtain a urea solution, the urea solution was added to the second mixture, 1.6μL perfluorooctyltrichlorosilane was slowly added dropwise, and stirred for 0.5h, and then 0.09g modified carbon nanotube particles were added, and a cell crusher was used for ultrasonication for 5min to obtain a coating solution, and the coating solution was sprayed onto the surface of the aluminum substrate at 48°C and a distance of 15cm, and cured at 150°C to obtain a loaded SiO 2 / CNTs fluorocarbon resin-based super hydrophobic coating, denoted as FEVE-SiO 2 / CNTs superhydrophobic coating.

[0057] S3, preparing a fluorocarbon resin-based composite super-slip coating: dissolving 0.1 g of methylene diphenyl diisocyanate in 5 mL of ethyl acetate and spraying it onto the FEVE-SiO 2 / CNTs super-hydrophobic coating was heated at 80 °C for 10 min to completely evaporate the solvent, and 1 g of hydroxy fluorosilicone oil was added dropwise to the FEVE-SiO 2 The surface of the super-hydrophobic coating of / CNTs was then placed in a vacuum drying oven and placed under a pressure of 0.06 MPa for 2 h to allow the hydroxyl fluorosilicone oil to fill the pores. The fluorocarbon resin-based composite super-slip coating was obtained by heating in an oven at 200 °C for 30 min, and the coating was recorded as FEVE-SiO 2 / CNTs@MDI SLIPS coating.

[0058] Example 3

[0059] A fluorocarbon resin-based composite super-slip coating and a preparation method thereof, comprising the following steps:

[0060] S1, preparing modified carbon nanotube particles: 0.7 g of carboxyl carbon nanotubes were dispersed in 40 mL of ethanol, then added to 15 μL of perfluorooctyltrichlorosilane under stirring for 4 h, dried at 80° C. for 12 h, and ground to obtain modified carbon nanotube particles.

[0061] S2, preparation of loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating: 2 g of fluorinated ethylene-(hydroxy-alkyl) vinyl ether and 0.1 g of curing agent N3390 were fully dispersed in a beaker containing 15 mL of ethyl acetate, and ultrasonicated for 10 min to obtain a first mixture. 0.8 mL of tetraethyl orthosilicate was transferred to a beaker containing 5 mL of ethanol with a dropper and stirred thoroughly. The ethanol solution of tetraethyl orthosilicate was added dropwise to the mixture. Then, 0.9 mL of tetraethyl orthosilicate was added to the mixture. 25% ammonia solution, and magnetically stirred for 30 minutes to obtain a second mixture, 0.13g urea was added to 0.5mL deionized water, and stirred continuously for 5 minutes until the urea was completely dissolved to obtain a urea solution, the urea solution was added to the second mixture, 3μL perfluorooctyltrichlorosilane was slowly added dropwise, and stirred for 0.5h, and then 0.11g modified carbon nanotube particles were added, and a cell crusher was used for ultrasonication for 5min to obtain a coating solution, and the coating solution was sprayed onto the surface of the aluminum substrate at 60°C and a distance of 15cm, and cured at 240°C to obtain a loaded SiO 2 / CNTs fluorocarbon resin-based super hydrophobic coating, denoted as FEVE-SiO 2 / CNTs superhydrophobic coating.

[0062] S3, preparing a fluorocarbon resin-based composite super-slip coating: dissolving 0.2 g of methylene diphenyl diisocyanate in 5 mL of ethyl acetate and spraying it onto the FEVE-SiO 2 / CNTs super-hydrophobic coating was heated at 80 °C for 10 min to completely evaporate the solvent, and 2 g of hydroxy fluorosilicone oil was added dropwise to the FEVE-SiO 2 The surface of the super-hydrophobic coating of / CNTs was then placed in a vacuum drying oven and placed under a pressure of 0.08 MPa for 2 h to allow the hydroxyl fluorosilicone oil to fill the pores. The fluorocarbon resin-based composite super-slip coating was obtained by heating in an oven at 200 °C for 30 min, and the coating was labeled as FEVE-SiO 2 / CNTs@MDI SLIPS coating.

[0063] Example 4

[0064] A fluorocarbon resin-based composite super-slip coating and a preparation method thereof, comprising the following steps:

[0065] S1, preparing modified carbon nanotube particles: 0.7 g of carboxyl carbon nanotubes were dispersed in 40 mL of ethanol, then added to 18 μL of perfluorooctyltrichlorosilane under stirring for 4 h, dried at 80° C. for 12 h, and ground to obtain modified carbon nanotube particles.

[0066] S2, preparation of loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating: 2 g of fluorinated ethylene-(hydroxy-alkyl) vinyl ether and 0.1 g of curing agent N3390 were fully dispersed in a beaker filled with 15 mL of ethyl acetate, and ultrasonicated for 10 min to obtain a first mixture. 0.7 mL of tetraethyl orthosilicate was transferred to a beaker filled with 5 mL of ethanol with a dropper and stirred thoroughly. The ethanol solution of tetraethyl orthosilicate was added dropwise to the mixture. Then, 0.6 mL of 25% ammonia solution was added to the mixture and magnetically stirred for 30 min to obtain a second mixture. 0.1 100 g urea was added into 0.5 mL deionized water, and stirred continuously for 5 min until the urea was completely dissolved to obtain a urea solution. The urea solution was added into the second mixture, and 2.5 μL perfluorooctyltrichlorosilane was slowly added dropwise, and stirred for 0.5 h. Then, 0.11 g modified carbon nanotube particles were added, and a cell crusher was used for ultrasonication for 5 min to obtain a coating solution. The coating solution was sprayed onto the surface of the aluminum substrate at 55 ° C and a distance of 15 cm, and cured at 200 ° C to obtain a SiO2-loaded carbon nanotube. 2 / CNTs fluorocarbon resin-based super hydrophobic coating, denoted as FEVE-SiO 2 / CNTs superhydrophobic coating.

[0067] S3, preparing a fluorocarbon resin-based composite super-slip coating: dissolving 0.1 g of methylene diphenyl diisocyanate in 5 mL of ethyl acetate and spraying it onto the FEVE-SiO 2 / CNTs super-hydrophobic coating was heated at 80 °C for 10 min to completely evaporate the solvent, and 2 g of hydroxy fluorosilicone oil was added dropwise to the FEVE-SiO 2 The surface of the super-hydrophobic coating of / CNTs was then placed in a vacuum drying oven and placed under a pressure of 0.07 MPa for 2 h to allow the hydroxyl fluorosilicone oil to fill the pores. The fluorocarbon resin-based composite super-slip coating was obtained and recorded as FEVE-SiO 2 / CNTs@MDI SLIPS coating.

[0068] Example 5

[0069] A fluorocarbon resin-based composite super-slip coating and a preparation method thereof, comprising the following steps:

[0070] S1, preparing modified carbon nanotube particles: 0.7 g of carboxyl carbon nanotubes were dispersed in 40 mL of ethanol, then added to 12 μL of perfluorooctyltrichlorosilane under stirring for 4 h, dried at 80° C. for 12 h, and ground to obtain modified carbon nanotube particles.

[0071] S2, preparation of loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating: 2 g of fluorinated ethylene-(hydroxy-alkyl) vinyl ether and 0.1 g of curing agent N3390 were fully dispersed in a beaker containing 15 mL of ethyl acetate, and ultrasonicated for 10 min to obtain a first mixture. 0.6 mL of tetraethyl orthosilicate was transferred to a beaker containing 5 mL of ethanol with a dropper and stirred thoroughly. The ethanol solution of tetraethyl orthosilicate was added dropwise to the mixture. Then, 0.5 mL of tetraethyl orthosilicate was added to the mixture. 25% ammonia solution, and magnetically stirred for 30 minutes to obtain a second mixture, 0.12g urea was added to 0.5mL deionized water, and stirred continuously for 5 minutes until the urea was completely dissolved to obtain a urea solution, the urea solution was added to the second mixture, 2μL perfluorooctyltrichlorosilane was slowly added dropwise, and stirred for 0.5h, and then 0.09g modified carbon nanotube particles were added, and cell disruption was used, and ultrasonication was performed for 5min to obtain a coating solution, and the coating solution was sprayed onto the surface of the aluminum substrate at 50°C and a distance of 15cm, and cured at 220°C to obtain a loaded SiO 2 / CNTs fluorocarbon resin-based super hydrophobic coating, denoted as FEVE-SiO 2 / CNTs superhydrophobic coating.

[0072] S3, preparing a fluorocarbon resin-based composite super-slip coating: dissolving 0.2 g of methylene diphenyl diisocyanate in 5 mL of ethyl acetate and spraying it onto the FEVE-SiO 2 / CNTs super-hydrophobic coating was heated at 80 °C for 10 min to completely evaporate the solvent, and 1 g of hydroxy fluorosilicone oil was added dropwise to the FEVE-SiO 2 The surface of the super-hydrophobic coating of / CNTs was then placed in a vacuum drying oven and placed under a pressure of 0.06 MPa for 2 h to allow the hydroxyl fluorosilicone oil to fill the pores. The fluorocarbon resin-based composite super-slip coating was obtained by heating in an oven at 200 °C for 30 min, and the coating was recorded as FEVE-SiO 2 / CNTs@MDI SLIPS coating.

[0073] In order to further illustrate the effect of the present invention, the present invention also provides a comparative example, which is as follows:

[0074] Comparative Example 1

[0075] Compared with Example 1, the difference is that no SiO 2 Instead of in situ cross-linking, they are added directly.

[0076] A fluorocarbon resin-based composite super-slip coating and a preparation method thereof, comprising the following steps:

[0077] S1, preparation of modified carbon nanotube particles: 0.7 g of carboxyl carbon nanotubes were dispersed in 40 mL of ethanol, then added to 10 μL of perfluorooctyltrichlorosilane under stirring for 4 h, dried at 80° C. for 12 h, and ground to obtain modified carbon nanotube particles.

[0078] S2, preparation of loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating: 2 g of fluorinated ethylene-(hydroxy-alkyl) vinyl ether and 0.1 g of curing agent N3390 were fully dispersed in a beaker containing 15 mL of ethyl acetate, and ultrasonicated for 10 min to obtain a first mixture. 0.188 g of silica was added to the first mixture, and magnetic stirring was performed for 30 min to obtain a second mixture. 0.1 g of urea was added to 0.5 mL of deionized water, and the mixture was continuously stirred for 5 min until the urea was completely dissolved to obtain a urea solution. The urea solution was added to the second mixture, and 2 μL of perfluorooctyltrichlorosilane was slowly added dropwise and stirred for 0.5 h. 0.1 g of modified carbon nanotube particles was added, and a cell crusher was used for ultrasonication for 5 min to obtain a coating solution. The coating solution was sprayed onto the surface of the aluminum substrate at 50°C and a distance of 15 cm, and cured at 180°C to obtain a loaded SiO 2 / CNTs fluorocarbon resin-based super hydrophobic coating, denoted as FEVE / SiO 2 / CNTs superhydrophobic coating.

[0079] S3, preparing a fluorocarbon resin-based composite super-slip coating: 0.15 g of methylene diphenyl diisocyanate was dissolved in 5 mL of ethyl acetate and sprayed onto the FEVE-SiO 2 / CNTs super-hydrophobic coating was heated at 80 °C for 10 min to completely evaporate the solvent, and 1.5 g of hydroxy fluorosilicone oil was added dropwise to the FEVE-SiO 2 The surface of the super-hydrophobic coating of / CNTs was then placed in a vacuum drying oven and placed under a pressure of 0.08 MPa for 2 h to allow the hydroxyl fluorosilicone oil to fill the pores. The coating was then heated in an oven at 180 °C for 30 min to obtain a fluorocarbon resin-based composite super-slip coating, which was recorded as FEVE-SiO 2 / CNTs@MDI SLIPS coating.

[0080] Comparative Example 2

[0081] Compared with Example 1, the difference is that urea is replaced by an equal amount of ammonium bicarbonate.

[0082] A fluorocarbon resin-based composite super-slip coating and a preparation method thereof, comprising the following steps:

[0083] S1, preparation of modified carbon nanotube particles: 0.7 g of carboxyl carbon nanotubes were dispersed in 40 mL of ethanol, then added to 10 μL of perfluorooctyltrichlorosilane under stirring for 4 h, dried at 80° C. for 12 h, and ground to obtain modified carbon nanotube particles.

[0084] S2, preparation of loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating: 2 g of fluorinated ethylene-(hydroxy-alkyl) vinyl ether and 0.1 g of curing agent N3390 were fully dispersed in a beaker filled with 15 mL of ethyl acetate, and ultrasonicated for 10 min to obtain a first mixture. 0.7 mL of tetraethyl orthosilicate was transferred to a beaker filled with 5 mL of ethanol with a dropper and stirred thoroughly. The ethanol solution of tetraethyl orthosilicate was added dropwise to the mixture. Then, 0.7 mL of 25% ammonia solution was added to the mixture and magnetically stirred for 30 min to obtain a second mixture. 0.1 100 g of ammonium bicarbonate was added to 0.5 mL of deionized water, and the mixture was stirred continuously for 5 min until the ammonium bicarbonate was completely dissolved to obtain an ammonium bicarbonate solution. The ammonium bicarbonate solution was added to the second mixture, and 2 μL of perfluorooctyltrichlorosilane was slowly added dropwise, and the mixture was stirred for 0.5 h. Then, 0.1 g of modified carbon nanotube particles was added, and the mixture was ultrasonicated for 5 min using a cell crusher to obtain a coating solution. The coating solution was sprayed onto the surface of the aluminum substrate at 50° C. and a distance of 15 cm, and the coating solution was cured at 180° C. to obtain a loaded SiO 2 / CNTs fluorocarbon resin-based super hydrophobic coating, denoted as FEVE-SiO 2 / CNTs superhydrophobic coating.

[0085] S3, preparing a fluorocarbon resin-based composite super-slip coating: 0.15 g of methylene diphenyl diisocyanate was dissolved in 5 mL of ethyl acetate and sprayed onto the FEVE-SiO 2 / CNTs super-hydrophobic coating was heated at 80 °C for 10 min to completely evaporate the solvent, and 1.5 g of hydroxy fluorosilicone oil was added dropwise to the FEVE-SiO 2 The surface of the super-hydrophobic coating of / CNTs was then placed in a vacuum drying oven and placed under a pressure of 0.08 MPa for 2 h to allow the hydroxyl fluorosilicone oil to fill the pores. The coating was then heated in an oven at 180 °C for 30 min to obtain a fluorocarbon resin-based composite super-slip coating, which was recorded as FEVE-SiO 2 / CNTs@MDI SLIPS coating.

[0086] Comparative Example 3

[0087] Compared with Example 1, the difference is that the carbon nanotube particles are not modified by perfluorooctyltrichlorosilane.

[0088] A fluorocarbon resin-based composite super-slip coating and a preparation method thereof, comprising the following steps:

[0089] S1, 0.1 g carbon nanotube particles without modification.

[0090] S2, preparation of loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating: 2 g of fluorinated ethylene-(hydroxy-alkyl) vinyl ether and 0.1 g of curing agent N3390 were fully dispersed in a beaker filled with 15 mL of ethyl acetate, and ultrasonicated for 10 min to obtain a first mixture. 0.7 mL of tetraethyl orthosilicate was transferred to a beaker filled with 5 mL of ethanol with a dropper and stirred thoroughly. The ethanol solution of tetraethyl orthosilicate was added dropwise to the mixture. Then, 0.7 mL of 25% ammonia solution was added to the mixture and magnetically stirred for 30 min to obtain a second mixture. 0.1 100 g urea was added into 0.5 mL deionized water, and the mixture was stirred continuously for 5 min until the urea was completely dissolved to obtain a urea solution. The urea solution was added into the second mixture, and 2 μL perfluorooctyltrichlorosilane was slowly added dropwise, and the mixture was stirred for 0.5 h. Then, 0.1 g carbon nanotube particles were added, and the mixture was ultrasonicated for 5 min using a cell crusher to obtain a coating solution. The coating solution was sprayed onto the surface of the aluminum substrate at 50° C. and a distance of 15 cm, and the coating solution was cured at 180° C. to obtain a SiO2-loaded carbon nanotube. 2 / CNTs fluorocarbon resin-based super hydrophobic coating, denoted as FEVE-SiO 2 / CNTs superhydrophobic coating.

[0091] S3, preparing a fluorocarbon resin-based composite super-slip coating: 0.15 g of methylene diphenyl diisocyanate was dissolved in 5 mL of ethyl acetate and sprayed onto the FEVE-SiO 2 / CNTs super-hydrophobic coating was heated at 80 °C for 10 min to completely evaporate the solvent, and 1.5 g of hydroxy fluorosilicone oil was added dropwise to the FEVE-SiO 2 The surface of the super-hydrophobic coating of / CNTs was then placed in a vacuum drying oven and placed under a pressure of 0.08 MPa for 2 h to allow the hydroxyl fluorosilicone oil to fill the pores. The coating was then heated in an oven at 180 °C for 30 min to obtain a fluorocarbon resin-based composite super-slip coating, which was recorded as FEVE-SiO 2 / CNTs@MDI SLIPS coating.

[0092] Comparative Example 4

[0093] Compared with Example 1, the difference is that the amount of perfluorooctyltrichlorosilane in S2 is reduced from 2 μL to 1 μL.

[0094] A fluorocarbon resin-based composite super-slip coating and a preparation method thereof, comprising the following steps:

[0095] S1, preparation of modified carbon nanotube particles: 0.7 g of carboxyl carbon nanotubes were dispersed in 40 mL of ethanol, then added to 10 μL of perfluorooctyltrichlorosilane under stirring for 4 h, dried at 80° C. for 12 h, and ground to obtain modified carbon nanotube particles.

[0096] S2, preparation of loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating: 2 g of fluorinated ethylene-(hydroxy-alkyl) vinyl ether and 0.1 g of curing agent N3390 were fully dispersed in a beaker filled with 15 mL of ethyl acetate, and ultrasonicated for 10 min to obtain a first mixture. 0.7 mL of tetraethyl orthosilicate was transferred to a beaker filled with 5 mL of ethanol with a dropper and stirred thoroughly. The ethanol solution of tetraethyl orthosilicate was added dropwise to the mixture. Then, 0.7 mL of 25% ammonia solution was added to the mixture and magnetically stirred for 30 min to obtain a second mixture. 0.1 100 g urea was added into 0.5 mL deionized water, and stirred continuously for 5 min until the urea was completely dissolved to obtain a urea solution. The urea solution was added into the second mixture, 1 μL perfluorooctyltrichlorosilane was slowly added dropwise, and stirred for 0.5 h. Then 0.1 g modified carbon nanotube particles were added, and a cell crusher was used for ultrasonication for 5 min to obtain a coating solution. The coating solution was sprayed onto the surface of the aluminum substrate at 50 ° C and a distance of 15 cm, and cured at 180 ° C to obtain a SiO2-loaded carbon nanotube. 2 / CNTs fluorocarbon resin-based super hydrophobic coating, denoted as FEVE-SiO 2 / CNTs superhydrophobic coating.

[0097] S3, preparing a fluorocarbon resin-based composite super-slip coating: 0.15 g of methylene diphenyl diisocyanate was dissolved in 5 mL of ethyl acetate and sprayed onto the FEVE-SiO 2 / CNTs super-hydrophobic coating was heated at 80 °C for 10 min to completely evaporate the solvent, and 1.5 g of hydroxy fluorosilicone oil was added dropwise to the FEVE-SiO 2 The surface of the super-hydrophobic coating of / CNTs was then placed in a vacuum drying oven and placed under a pressure of 0.08 MPa for 2 h to allow the hydroxyl fluorosilicone oil to fill the pores. The coating was then heated in an oven at 180 °C for 30 min to obtain a fluorocarbon resin-based composite super-slip coating, which was recorded as FEVE-SiO 2 / CNTs@MDI SLIPS coating.

[0098] Comparative Example 5

[0099] Compared with Example 1, the difference is that methylene diphenyl diisocyanate is not used, and hydroxy fluorosilicone oil is directly impregnated on the coating surface.

[0100] A fluorocarbon resin-based composite super-slip coating and a preparation method thereof, comprising the following steps:

[0101] S1, preparation of modified carbon nanotube particles: 0.7 g of carboxyl carbon nanotubes were dispersed in 40 mL of ethanol, then added to 10 μL of perfluorooctyltrichlorosilane under stirring for 4 h, dried at 80° C. for 12 h, and ground to obtain modified carbon nanotube particles.

[0102] S2, preparation of loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating: 2 g of fluorinated ethylene-(hydroxy-alkyl) vinyl ether and 0.1 g of curing agent N3390 were fully dispersed in a beaker filled with 15 mL of ethyl acetate, and ultrasonicated for 10 min to obtain a first mixture. 0.7 mL of tetraethyl orthosilicate was transferred to a beaker filled with 5 mL of ethanol with a dropper and stirred thoroughly. The ethanol solution of tetraethyl orthosilicate was added dropwise to the mixture. Then, 0.7 mL of 25% ammonia solution was added to the mixture and magnetically stirred for 30 min to obtain a second mixture. 0.1 100 g urea was added into 0.5 mL deionized water, and stirred continuously for 5 min until the urea was completely dissolved to obtain a urea solution. The urea solution was added into the second mixture, and 2 μL perfluorooctyltrichlorosilane was slowly added dropwise, and stirred for 0.5 h. Then, 0.1 g modified carbon nanotube particles were added, and a cell crusher was used for ultrasonication for 5 min to obtain a coating solution. The coating solution was sprayed onto the surface of the aluminum substrate at 50 ° C and a distance of 15 cm, and cured at 180 ° C to obtain a SiO2-loaded carbon nanotube. 2 / CNTs fluorocarbon resin-based super hydrophobic coating, denoted as FEVE-SiO 2 / CNTs superhydrophobic coating.

[0103] S3, preparation of fluorocarbon resin-based composite super-slip coating: 1.5 g of hydroxy fluorosilicone oil was added dropwise to the FEVE-SiO 2 The surface of the super-hydrophobic coating of / CNTs was then placed in a vacuum drying oven and placed under a pressure of 0.08 MPa for 2 h to allow the hydroxyl fluorosilicone oil to fill the pores. The coating was then heated in an oven at 180 °C for 30 min to obtain a fluorocarbon resin-based composite super-slip coating, which was recorded as FEVE-SiO 2 / CNTsSLIPS coating.

[0104] The corrosion resistance, anti-scaling performance and underwater durability of the fluorocarbon resin-based composite super-slip coatings prepared in the above-mentioned Examples 1 to 5 and Comparative Examples 1 to 5 were tested, and the results are shown in Table 1 below.

[0105] 1. Corrosion resistance

[0106] The initial impedance modulus of the fluorocarbon resin-based composite super-slip coating prepared by the present invention is 1.22×10 8 Ω cm 2Compared with traditional super-slip coatings in recent years, the details are as follows:

[0107] 1) Long YF, Yin XX, Mu P, Wang QT, Hu JJ, Li J. Slippery liquid-infused porous surface (SLIPS) with superior liquid repellency, anti-corrosion, anti-icing and intensified durability for protecting substrates. Chem Eng J. 2020;401:126137. In the above literature, the SLIPS coating with a unique flower-like structure prepared by porous attapulgite nanorods and inorganic aluminum phosphate has a |Z|0.01Hz =10 4 ~10 5 Ω cm 2 .

[0108] 2) Yu YZ, Wei YS, Liu QY, Lin ZF, Li BiZ, Xue XY, Qiu R, Ouyang YB. One-step electrodeposition enables bioinspired SLIPS coating for corrosion inhibition of Mg-Li alloy. Colloids Surf A. 2023;676:132208. In the above literature, a universal deep eutectic solvent DES was used to prepare a corrosion-resistant and anti-icing super-slip coating by one-step electrodeposition. The Z|0.01Hz = 10 4 Ωcm 2 .

[0109] Compared with the super-slip coating in the prior art, the FEVE-SiO 2 The corrosion protection performance of CNTs@MDI SLIPS coating is improved by 10 3 times.

[0110] 2. Anti-scaling performance

[0111] During the testing process, the contents of C, O and Ca elements on the surface of the coating samples were tested. 2 The content of Ca in the super-hydrophobic coating of CNTs accounts for 11.9% of the three elements. 2The mass proportion of Ca element in the / CNTs@MDI SLIPS coating is only 0.42%, and the scale inhibition performance is improved by 96.47%, showing its excellent anti-scaling performance.

[0112] 3. Underwater durability

[0113] After 14 days of underwater immersion, a sliding angle of 7.18° was exhibited, which was attributed to the strong interfacial interaction on the coating surface that enhanced the stability of the oil layer.

[0114] Table 1 Performance test table of the composite coating of the present invention

[0115]

[0116] As shown in Table 1, the fluorocarbon resin-based composite super-slip coating prepared by the present invention has excellent corrosion resistance, anti-scaling performance and underwater durability. The initial impedance modulus of the fluorocarbon resin-based composite super-slip coating prepared by the present invention can reach 3.2×10 8 Ω cm 2 , the mass proportion of Ca element can reach 0.39wt%, and the sliding angle of the fluorocarbon resin-based composite super-slip coating can reach 6.9° after immersion for 14 days. The composite coatings prepared in the above comparative examples 1 to 5 have poor performance, and the reasons are analyzed as follows:

[0117] In Comparative Example 1, Example 1 of the present invention uses hydrolysis of tetraethyl orthosilicate and fluorocarbon resin for in-situ crosslinking. However, in Comparative Example 1, tetraethyl orthosilicate is replaced with an equal mass of silica particles for physical addition, which seriously affects the mechanical stability of the coating. Taking 3000 revolutions of friction cycle as an example, the thickness loss of tetraethyl orthosilicate after hydrolysis is 66 μm, and the thickness loss of the physically added silica coating is 92 μm.

[0118] In Comparative Example 2, if urea is replaced with ammonium bicarbonate for pore formation, the bottom of the coating substrate will be exposed, and the overall mechanical stability will deteriorate. The reason is that the decomposition temperature of ammonium bicarbonate is too low, which will affect the cross-linking of the fluorocarbon resin itself. Therefore, urea that decomposes at high temperature is required for pore formation. However, excessive addition of urea will also affect the mechanical stability of the coating itself.

[0119] In Comparative Example 3, the carboxyl carbon nanotubes are not fluorinated and hydrophobically modified with perfluorooctyltrichlorosilane. Even if the amount of carboxyl carbon nanotubes is increased, the construction of a super-hydrophobic surface cannot be achieved. Because although carbon nanotube particles can enrich the nanostructure and improve the hydrophobic performance, the hydrophilicity of the carboxyl group will reduce the hydrophobic performance from another level. Therefore, it is necessary to modify them with fluorine to achieve the construction of a super-hydrophobic surface.

[0120] In comparative example 4, the amount of perfluorooctyl trichlorosilane is too low to ensure hydrophobicity, and too high to ensure lipophilicity. After testing, only within the dosage range specified in the present invention can the super hydrophobic and super lipophilic properties of the composite coating be achieved simultaneously.

[0121] In Comparative Example 5, methylene diphenyl diisocyanate was not used, and hydroxy fluorosilicone oil was directly impregnated in the loaded SiO 2 / CNTs fluorocarbon resin-based super-hydrophobic coating surface, the oil film stability is insufficient. In the spin coating test, it can be found that the oil film loss rate of the coating without methylene diphenyl diisocyanate is 79.46%, and the oil film loss rate of the coating with methylene diphenyl diisocyanate is 10.41%.

[0122] Figure 1 The figure shows the effect of different contents of carbon nanotubes on the wettability of fluorocarbon resin-based composite super-slip coating. Figure 1 As shown in Figure 2, with the increase of carbon nanotube content, FEVE-SiO 2 The hydrophobic angle WCA value of the / CNTs coating increases, and the oleophobic angle OCA increases first and then decreases. 2 / CNTs coating has super hydrophobicity and super oleophilicity of WCA, with WCA=152.24°±1.5° and OCA=6.76°±1.5°. When the content of carbon nanotubes increases to 5wt%, it is considered that adding excessive carbon nanotubes will weaken the cross-linking of fluorocarbon resin and reduce the FEVE-SiO 2 / CNTs coating mechanical stability, it is determined that 5wt% of carbon nanotube particles is the preparation of superhydrophobic and superoleophilic FEVE-SiO 2 / Optimal particle content of CNTs coating.

[0123] Figure 2 This is the impedance diagram of the fluorocarbon resin-based composite super-slip coating prepared by the present invention. Figure 2 It can be seen that the initial |0.01Hz of the fluorocarbon resin-based composite super-slip coating prepared by the present invention is as high as 1.22×10 8 Ω cm 2 After immersion for 15 days, it still remained at 6.91×107Ω cm 2 . Figure 2 A diagonal line is shown in the figure, indicating good anti-corrosion performance. This is mainly because the bridging molecule MDI fixes the lubricant on the coating surface through the synergistic anchoring effect of π-OH interaction and interfacial covalent bond formation, forming a more stable oil layer, thereby delaying the penetration of the sodium chloride solution into the interface between the Al substrate and the coating.

[0124] Figure 3 FEVE-SiO prepared in Example 1 of the present invention 2 / CNTs coating, FEVE-SiO 2 Comparative bar graph of the Ca content on the surface of the FEVE-SiO2 / CNTs SLIPS coating prepared in Example 5 and the FEVE-SiO2 / CNTs SLIPS coating prepared in Example 5. Figure 3 It can be seen that FEVE-SiO 2 The Ca content of the super-hydrophobic coating of / CNTs is as high as 11.9wt%. 2 The Ca content of the FEVE-SiO2 / CNTs slip coating decreased to 0.48 wt%, which was due to the smooth and hydrophobic oil layer, which enhanced the shielding property of the coating, prevented the growth and adhesion of calcium carbonate, and improved the anti-fouling performance. 2 A more stable oil layer was formed on the surface of the FEVE-SiO2 / CNTs@MDI sliding coating, which inhibited the normal growth of calcium carbonate. 2 / CNTs@MDI coating showed the best scale inhibition performance. After immersion in salt water for 48h, FEVE-SiO 2 The Ca content on the surface of the / CNTs@MDI super-slip coating is the lowest, which is only 0.42 wt%.

[0125] Figure 4 The FEVE-SiO prepared in the present invention 2 Changes in water contact angle WCA and water sliding angle WSA of / CNTs@MDI SLIPS coating after immersion in water for 14 days. Figure 4 It can be seen that MDI fixes the lubricant on the coating surface through the synergistic anchoring effect formed by π-OH interaction and interfacial covalent bonds, forming a more stable oil layer, making FEVE-SiO 2 After being immersed in water for 14 days, the / CNTs@MDI coating still has excellent super-slip properties, with a sliding angle of only 7.4°.

[0126] In summary, the present invention adopts SiO 2 In situ hybridization, urea thermal decomposition, and embedded CNTs jointly constructed a hierarchical porous structure with a covalent interpenetrating network, which significantly improved the interfacial interaction within the coating and enhanced the mechanical durability of the coating.

[0127] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preparing a fluorocarbon resin-based composite super-slip coating, characterized in that: The following steps are involved: Carboxyl carbon nanotubes are subjected to hydrophobic and lipophilic modification to obtain modified carbon nanotube particles; Fluorinated ethylene-(hydroxy-alkyl) vinyl ether and a curing agent are used as coating raw materials, ethyl orthosilicate and ammonia water are added to generate SiO2, a SiO2-loaded fluorocarbon resin-based solution is obtained, urea, a hydrophobic lipophilic modifier and the modified carbon nanotube particles are added, ultrasonication is performed to obtain a coating solution, the coating solution is sprayed at 48°C to 60°C to obtain a wet coating, and the coating solution is cured at 150°C to 240°C, the fluorinated ethylene-(hydroxy-alkyl) vinyl ether and the curing agent are cross-linked and cross-linked with SiO2, and urea is pyrolyzed to generate pores to obtain a SiO2 / CNTs-loaded fluorocarbon resin-based super-hydrophobic coating; A solution containing isocyanate groups is sprayed on the SiO2 / CNTs loaded fluorocarbon resin-based super-hydrophobic coating to obtain a modified coating, and hydroxyfluorosilicone oil is dropped onto the surface of the modified coating, placed in a vacuum, and reacted at 180°C to 240°C. The isocyanate groups react with the hydroxyfluorosilicone oil to obtain a fluorocarbon resin-based composite super-slippery coating.

2. The method for preparing the fluorocarbon resin-based composite super-slip coating according to claim 1, characterized in that: The dosage ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to tetraethyl orthosilicate is 1 g: 0.3 mL to 0.4 mL, the concentration of the ammonia water is 25%, and the volume ratio of the tetraethyl orthosilicate to the ammonia water is 1: 0.8 to 1.

2.

3. The method for preparing the fluorocarbon resin-based composite super-slip coating according to claim 1, characterized in that: The mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to the carbon nanotube particles is 2:0.09-0.

11.

4. The method for preparing the fluorocarbon resin-based composite super-slip coating according to claim 1, characterized in that: The mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to urea is 2:0.08-0.

13.

5. The method for preparing the fluorocarbon resin-based composite super-slip coating according to claim 1, characterized in that: The solution containing isocyanate groups is an ethyl acetate solution of methylene diphenyl diisocyanate, and the mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to methylene diphenyl diisocyanate is 2:0.1-0.

2.

6. The method for preparing a fluorocarbon resin-based composite super-slip coating according to claim 1, characterized in that: The mass ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to the hydroxy fluorosilicone oil is 2:1-2.

7. The method for preparing a fluorocarbon resin-based composite super-slip coating according to claim 1, characterized in that: The preparation method of the modified carbon nanotube particles is specifically as follows: in a stirring state, perfluorooctyltrichlorosilane is added to an ethanol solution of carboxyl carbon nanotubes according to a usage ratio of 0.7g carboxyl carbon nanotubes to 10μL~20μL perfluorooctyltrichlorosilane, reacting, drying, and grinding to obtain modified carbon nanotube particles.

8. The method for preparing a fluorocarbon resin-based composite super-slip coating according to claim 1, characterized in that: The hydrophobic and lipophilic modifier is perfluorooctyltrichlorosilane, and the usage ratio of the fluorinated ethylene-(hydroxy-alkyl) vinyl ether to perfluorooctyltrichlorosilane is 1g:0.8μL~1.5μL.

9. The method for preparing a fluorocarbon resin-based composite super-slip coating according to claim 1, characterized in that: After hydroxy fluorosilicone oil is dropped onto the surface of the modified coating, it is placed under a vacuum condition of 0.06 MPa to 0.08 MPa for 2 hours.

10. A fluorocarbon resin-based composite super-slip coating prepared according to the preparation method according to any one of claims 1 to 9.

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