Composite seepage-proof coating, its preparation method and composite seepage-proof coating coating

Abstract

This invention relates to the field of anti-seepage coatings, and discloses a composite anti-seepage coating, its preparation method, and the composite anti-seepage coating coating itself. The method includes: 1) mixing and drying fluorescent probe molecules and modified hydroxyapatite in the presence of a solvent to obtain a solid product containing fluorescent molecular probes; 2) mixing the solid product obtained in step 1) with epoxy resin and a curing agent to obtain a composite anti-seepage coating, wherein the mass ratio of the fluorescent probe molecules to the modified hydroxyapatite is 1:5-35, and the modified hydroxyapatite is hydroxyapatite grafted onto a molecular sieve imidazole framework material. The composite anti-seepage coating preparation method of this invention has the advantages of improving the self-diagnostic performance, physical barrier performance, and anti-seepage performance of the coating, making up for the shortcomings of existing coating technologies that cannot simultaneously possess self-diagnostic and self-repairing functions, and is conducive to promoting the application and development of highly anti-seepage and anti-corrosion coatings.

Description

Technical Field

[0001] This invention relates to the field of anti-seepage coatings, specifically to a composite anti-seepage coating, its preparation method, and the composite anti-seepage coating coating itself. Background Technology

[0002] Fluorescent probes, due to their unique photoluminescence properties, have been widely used in metal corrosion detection and damage localization. This technology utilizes the change in fluorescence signal generated by the combination of a fluorescent probe with metal ions or H+ / OH- ions produced during corrosion to indicate the occurrence of corrosion. Compared with traditional metal corrosion detection methods such as weight loss, electrochemical methods, noise methods, X-ray methods, and ultrasonic methods, fluorescent probe technology can detect early-stage metal corrosion and has advantages such as in-situ detection, direct visualization, and high sensitivity, and is completely non-destructive to the tested metal during the detection process. As a novel metal corrosion detection method, fluorescent probe technology is also widely used in metal anti-corrosion coatings. Adding fluorescent probes to organic resins to create composite coatings enables the coatings to have self-detection capabilities. Applying these coatings to steel surfaces creates intelligent coatings with self-diagnostic corrosion functions. When the coating is damaged, the iron ions or H+ / OH- ions generated by steel corrosion react with the fluorescent probes, producing a fluorescence signal, thus diagnosing steel corrosion. However, this technology also has drawbacks, such as the poor stability of the fluorescent probes, which can react with organic resins or additives in the coating, thereby reducing the coating's barrier and shielding performance against corrosive media. Porous nanomaterials hold significant promise for applications in coatings. Their ample internal cavities serve as excellent carriers for active substances. By uniformly dispersing porous nanomaterials within the coating, when defects occur, the nanomaterials can actively release active substances in response to stimuli, thereby repairing the coating defects. Employing porous nanomaterial loading technology can prevent direct contact between active substances and the coating, thus avoiding inactivation reactions that could affect coating performance. However, the application conditions of porous nanomaterials in coatings are relatively stringent, requiring optimization and control of the preparation process to enhance their carrying capacity and self-healing effects.

[0003] CN105802452A discloses a method for preparing a graphene coating, which mainly involves dispersing graphene in a resin to create an anti-corrosion coating with partial anti-seepage function.

[0004] CN114686085A discloses a corrosion self-diagnostic coating based on ion exchange and its preparation method. The coating is mainly made by mixing copper salts, organic ligands and organic resins and applying them to the surface of the target metal. The anti-corrosion coating prepared by this method will produce obvious color changes after being damaged, thus realizing the diagnosis of steel corrosion.

[0005] CN114618760A discloses a photothermal responsive nanofiber self-healing coating and its preparation method. The method involves loading photothermal agent copper hydroxynitrate nanoparticles onto the surface of nanofibers through self-assembly, adding them to an organic resin to form a coating, and then applying it to a metal surface. When the metal surface is damaged, this coating can activate the photothermal effect of the copper hydroxynitrate nanoparticles loaded on the nanofibers through light irradiation, converting light into heat and achieving rapid repair of cracks in the organic coating.

[0006] These three approaches all focus on enhancing only one aspect of the coating's corrosion resistance, self-diagnostic properties, or self-healing properties, failing to address all aspects simultaneously. Therefore, developing a waterproof coating that simultaneously possesses self-diagnostic, self-healing, and corrosion-resistant barrier properties is of great significance and necessity. Summary of the Invention

[0007] The purpose of this invention is to overcome the problems existing in the prior art and provide a composite anti-seepage coating, its preparation method and the composite anti-seepage coating coating. The composite anti-seepage coating can generate a fluorescent indication effect in response to the stimulation signal of local damage and form an inhibitory corrosion effect on the exposed metal corrosion process at the defect location, thereby exhibiting excellent anti-seepage and anti-corrosion performance.

[0008] To achieve the above objectives, the present invention provides a method for preparing a composite anti-seepage coating, the method comprising the following steps:

[0009] 1) In the presence of a solvent, fluorescent probe molecules and modified hydroxyapatite are mixed and dried to obtain a solid product containing fluorescent molecular probes;

[0010] 2) Mix the solid product described in step 1) with epoxy resin and curing agent to obtain a composite waterproof coating;

[0011] The mass ratio of the fluorescent probe molecule to the modified hydroxyapatite is 1:5-35.

[0012] The modified hydroxyapatite is hydroxyapatite grafted onto a molecular sieve imidazole framework material.

[0013] Preferably, the mass ratio of the fluorescent probe molecule to the modified hydroxyapatite is 1:15-25.

[0014] Preferably, the weight ratio of the modified hydroxyapatite to the solvent is 1:80-120.

[0015] Preferably, the solvent is one or more of ethanol, diethyl ether, and phenol, with ethanol being the most preferred.

[0016] Preferably, the fluorescent probe molecule is one or more of N-[4-bis(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthylimide, N-(2-thiazolyl)-4-(1-piperidinyl)-1,8-naphthylimide, and N-(2-pyridinyl)-4-(1-piperidinyl)-1,8-naphthylimide, and more preferably N-[4-bis(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthylimide.

[0017] The mixing conditions include: a temperature of 20-30℃, a time of 8-12h, and a pressure of 8-12MPa;

[0018] Preferably, the mixing conditions include: a temperature of 24-26°C, a time of 9-11 hours, and a pressure of 10-11 MPa;

[0019] Preferably, the drying is centrifugal drying, and the drying conditions include: a centrifugal speed of 4000-8000 rpm, a temperature of 50-70℃, and a time of 2-6 h; more preferably, the drying conditions include: a centrifugal speed of 5000-7000 rpm, a temperature of 55-65℃, and a time of 3-5 h.

[0020] Preferably, the molecular sieve imidazole framework material is a metal-organic framework material, and more preferably, the metal-organic framework material ZIF-7.

[0021] Preferably, the modified hydroxyapatite is obtained by contacting hydroxyapatite with benzimidazole and zinc nitrate in the presence of an organic solvent.

[0022] Preferably, the mass ratio of hydroxyapatite, benzimidazole, and zinc nitrate is 1:16-17:5-6.

[0023] Preferably, the mass ratio of the hydroxyapatite to the organic solvent is 1:80-120.

[0024] Preferably, the organic solvent is dimethylformamide.

[0025] Preferably, the mass ratio of the solid product, the epoxy resin, and the curing agent is 1:11-16:3-9; more preferably, the mass ratio of the solid product, the epoxy resin, and the curing agent is 1:12-15.6:3.6-7.

[0026] Preferably, the epoxy resin is one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin.

[0027] Preferably, the curing agent is one or more of diethylenetriamine, triethylenetetramine, and hydroxyethylethylenediamine.

[0028] Preferably, the method further includes vacuum degassing the mixed product after mixing.

[0029] The conditions for vacuum degassing include: a vacuum pressure of -0.03 to -0.08 MPa and a temperature of 25-35°C.

[0030] According to a second aspect of the present invention, a composite anti-seepage coating prepared by the method for preparing the composite anti-seepage coating described in the first aspect of the present invention is provided.

[0031] According to a third aspect of the present invention, a composite anti-seepage coating is provided, wherein the composite anti-seepage coating is prepared using the composite anti-seepage coating preparation method described in the first aspect of the present invention or the composite anti-seepage coating described in the second aspect of the present invention.

[0032] Preferably, the composite anti-seepage coating is obtained by applying the composite anti-seepage coating to the surface of the substrate and then curing it.

[0033] Through the above technical solution, the fluorescent probe molecules encapsulated in hydroxyapatite nanocontainers modified with a molecular sieve imidazole framework in this invention avoid direct contact with other components of the coating, thus improving the self-diagnostic performance of the coating. Furthermore, the benzimidazole released by the molecular sieve imidazole framework-modified hydroxyapatite after metal corrosion can inhibit the corrosion process, exhibiting excellent physical barrier and anti-seepage properties. This overcomes the shortcomings of current coating technologies that cannot simultaneously possess self-diagnostic and self-repair functions, promoting the application and development of highly impermeable anti-corrosion coatings. Detailed Implementation

[0034] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0035] According to a first aspect of the present invention, a method for preparing a composite waterproofing coating is provided, wherein the method comprises:

[0036] 1) In the presence of a solvent, fluorescent probe molecules and modified hydroxyapatite are mixed and dried to obtain a solid product containing fluorescent molecular probes;

[0037] 2) Mix the solid product described in step 1) with epoxy resin and curing agent to obtain a composite waterproof coating.

[0038] The mass ratio of the fluorescent probe molecule to the modified hydroxyapatite is 1:5-35.

[0039] The modified hydroxyapatite is hydroxyapatite grafted onto a molecular sieve imidazole framework material.

[0040] In this invention, the modified hydroxyapatite is a molecular sieve imidazole framework material grafted with hydroxyapatite. "Molecular sieve imidazole framework material grafted with hydroxyapatite" refers to a material on which hydroxyapatite is grafted onto a molecular sieve imidazole framework material.

[0041] The imidazole molecular sieve framework material is preferably a metal-organic framework material, and more preferably a metal-organic framework material ZIF-7.

[0042] According to the present invention, preferably, the mass ratio of the fluorescent probe molecule to the modified hydroxyapatite is 1:5-35; more preferably, the mass ratio of the fluorescent probe molecule to the modified hydroxyapatite is 1:15-25.

[0043] According to the present invention, preferably, the weight ratio of the modified hydroxyapatite to the solvent is 1:80-120.

[0044] According to the present invention, in order to improve the loading efficiency of fluorescent molecular probes and the solubility of reactants, the solvent contained in step 1) is preferably selected from one or more of ethanol, diethyl ether and phenol; more preferably, the solvent is ethanol.

[0045] According to the present invention, in order to enable the anti-seepage coating to generate a fluorescent indication effect in response to the corrosion signal of the base metal and realize the corrosion self-diagnosis function, preferably, the fluorescent probe molecule is one or more of N-[4-bis(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide, N-(2-thiazolyl)-4-(1-piperidinyl)-1,8-naphthalimide and N-(2-pyridinyl)-4-(1-piperidinyl)-1,8-naphthalimide; more preferably, the fluorescent probe molecule is N-[4-bis(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide.

[0046] According to the present invention, preferably, the mixing conditions include: a temperature of 20-30°C, a time of 8-12 hours, and a pressure of 8-12 MPa; more preferably, the mixing conditions include: a temperature of 24-26°C, a time of 9-11 hours, and a pressure of 10-11 MPa.

[0047] According to the present invention, the drying can be performed using methods commonly used in the art, and preferably, the drying is centrifugal drying.

[0048] Preferably, the drying conditions include: a centrifugal speed of 4000-8000 rpm, a temperature of 50-70℃, and a time of 2-6 h; more preferably, the drying conditions include: a centrifugal speed of 5000-7000 rpm, a temperature of 55-65℃, and a time of 3-5 h.

[0049] According to the present invention, in step 1), the amount of solvent can be selected according to the amount of modified hydroxyapatite. Preferably, in step 1), the weight ratio of the modified hydroxyapatite to the solvent is 1:80-120; more preferably, the weight ratio of the modified hydroxyapatite to the solvent is 1:90-110.

[0050] In this invention, in order to encapsulate the fluorescent probe molecules, effectively prevent the fluorescent probe molecules from binding with the organic resins and additives in the coating and thus becoming ineffective, and when the coating is corroded, it can respond to the pH changes caused by metal corrosion, release benzimidazole to repair the corroded substrate, and also release the internal fluorescent probe molecules to cause a fluorescent reaction, thereby realizing the corrosion self-diagnosis function. The modified hydroxyapatite is a molecular sieve imidazole framework material grafted with hydroxyapatite.

[0051] In this invention, preferably, the molecular sieve imidazole framework material grafted with hydroxyapatite is obtained by contacting hydroxyapatite with benzimidazole and zinc nitrate in the presence of an organic solvent.

[0052] The aforementioned hydroxyapatite can be obtained from commercially available products or synthesized using conventional methods in the art.

[0053] For example, hydroxyapatite can be obtained using the following method.

[0054] NH4H2PO4 and Ca(NO3)2 were dissolved in deionized water and then ultrasonically dispersed. The resulting dispersion was reacted with urea aqueous solution and centrifuged. The resulting solid was washed with deionized water and ethanol and dried to obtain hydroxyapatite powder.

[0055] According to the present invention, in the synthesis of the above-mentioned hydroxyapatite, preferably, the weight ratio of NH4H2PO4, Ca(NO3)2, deionized water and urea aqueous solution is 3.45:2.1-2.8:80-87:20.

[0056] According to the present invention, in the synthesis of the above-mentioned hydroxyapatite, preferably, the concentration of the urea aqueous solution is 0.007-0.009 mol / ml.

[0057] According to the present invention, in the synthesis of the above-mentioned hydroxyapatite, preferably, the reaction conditions include: a temperature of 110-125°C and a time of 2-5 h; more preferably, the reaction conditions include: a temperature of 120°C and a time of 3-4 h.

[0058] According to the present invention, in the synthesis of the above-mentioned hydroxyapatite, preferably, the washing can be performed using one or more of deionized water, ethanol, ethyl acetate and petroleum ether; more preferably, deionized water and ethanol are used.

[0059] Examples of organic solvents mentioned above include dimethylformamide.

[0060] According to the present invention, the above contact further includes the steps of centrifugation, washing, and drying after mixing the hydroxyapatite, benzimidazole, zinc nitrate, and organic solvent; preferably, the above contact includes the steps of centrifugation, washing, and drying after mixing the hydroxyapatite with the mixture of benzimidazole, zinc nitrate, and organic solvent.

[0061] The mixing conditions mentioned above include: a stirring speed of 1200-2000 rpm and a time of 0.5-3 h; more preferably, the mixing conditions mentioned above include: a stirring speed of 1500-1800 rpm and a time of 1-2 h.

[0062] The centrifugation conditions mentioned above include: a rotation speed of 4000-8000 rpm, a temperature of 50-70℃, and a time of 2-6 h; more preferably, the centrifugation conditions mentioned above include: a rotation speed of 5000-7000 rpm, a temperature of 55-65℃, and a time of 3-5 h.

[0063] The above washing can be carried out using ethyl acetate solvent.

[0064] The drying conditions described above include a temperature of 60-90°C and a time of 1-3 hours; more preferably, the drying conditions described above include a temperature of 70-80°C and a time of 2-2.5 hours.

[0065] According to the present invention, the amount of benzimidazole and zinc nitrate is selected according to the amount of hydroxyapatite. Preferably, the mass ratio of hydroxyapatite, benzimidazole and zinc nitrate is 1:16-17:5-6; more preferably, the mass ratio of hydroxyapatite, benzimidazole and zinc nitrate is 1:16.42-16.48:5.82-5.96.

[0066] According to the present invention, the amount of organic solvent is selected based on the amount of hydroxyapatite. Preferably, the mass ratio of hydroxyapatite to organic solvent is 1:80-120; more preferably, the mass ratio of hydroxyapatite to organic solvent is 1:90-110.

[0067] According to the present invention, in order to improve the physical properties and corrosion resistance of the composite waterproof coating, epoxy resin and curing agent are added in step 2).

[0068] Preferably, the epoxy resin is selected from one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin.

[0069] Preferably, the curing agent is selected from one or more of diethylenetriamine, triethylenetetramine, and hydroxyethylethylenediamine.

[0070] According to the present invention, preferably, the mass ratio of the solid product, the epoxy resin and the curing agent is 1:11-16:3-9; more preferably, the mass ratio of the solid product, the epoxy resin and the curing agent is 1:12-15.6:3.6-7.

[0071] According to the present invention, in order to remove air bubbles in the composite anti-seepage coating, the method further includes a step of vacuum degassing the mixed product after mixing.

[0072] Preferably, the conditions for vacuum degassing include: a vacuum pressure of -0.03 to -0.08 MPa and a temperature of 25-35°C; more preferably, the conditions for vacuum degassing include: a vacuum pressure of -0.05 MPa and a temperature of 28°C.

[0073] According to a second aspect of the present invention, a composite anti-seepage coating prepared by the method for preparing the composite anti-seepage coating described in the first aspect of the present invention is provided.

[0074] According to a third aspect of the present invention, a composite anti-seepage coating is provided, wherein the composite anti-seepage coating is prepared using the composite anti-seepage coating preparation method described in the first aspect of the present invention or the composite anti-seepage coating described in the second aspect of the present invention.

[0075] According to the present invention, preferably, the composite anti-seepage coating is obtained by applying the composite anti-seepage coating to the surface of a substrate and then curing it.

[0076] The present invention will be described in detail below through embodiments, but the present invention is not limited to the following embodiments.

[0077] Preparation Example 1

[0078] Two parts by weight of 4-bromo-1,8-naphthalene anhydride (purchased from Anshan Huifeng Chemical Co., Ltd.) and 0.5 parts by weight of p-phenylenediamine (purchased from Anshan Huifeng Chemical Co., Ltd.) were dissolved in a mixed solvent of 140 parts by weight of ethanol and 10 parts by weight of water, and refluxed for 2 hours under nitrogen protection. After standing until a solid precipitated, the solution was filtered, washed with ethanol, and dried to obtain N-(4-aminophenyl)-4-bromo-1,8-naphthalimide solid.

[0079] The obtained 2.1 parts by weight of N-(4-aminophenyl)-4-bromo-1,8-naphthalimide solid and 4.2 parts by weight of hexahydropyridine (purchased from Shanghai Aladdin Chemical Co., Ltd.) were dissolved in 60 parts by weight of ethylene glycol monomethyl ether (purchased from Wuxi Mezan Chemical Co., Ltd.). The mixture was refluxed for 4 hours under nitrogen protection, and then filtered and washed with ethanol to obtain N-(4-aminophenyl)-4-(1-piperidinyl)-1,8-naphthalimide solid.

[0080] 1.2 parts by weight of the obtained N-(4-aminophenyl)-4-(1-piperidinyl)-1,8-naphthalimide solid was dissolved in 150 parts by weight of ethanol and 20 parts by weight of acetic acid. The reaction was carried out by passing ethylene oxide through a -10°C cold bath. The resulting reaction solution was then subjected to vacuum distillation to remove the solvent, yielding a solid powder. The obtained solid powder was dissolved in dichloromethane (purchased from Wuxi Mezan Chemical Co., Ltd.), washed with potassium carbonate aqueous solution, and the solvent was then removed by distillation to obtain N-[4-bis(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide solid (NHAN).

[0081] Example 1

[0082] (1) 3.45 parts by weight of NH4H2PO4 (purchased from Sinopharm Chemical Reagent Co., Ltd.) and 2.4 parts by weight of Ca(NO3)2 (purchased from Sinopharm Chemical Reagent Co., Ltd.) were added to 80 parts by weight of deionized water and dissolved and then ultrasonically dispersed. The resulting dispersion mixture was added to 20 parts by weight of urea aqueous solution with a concentration of 0.0075 mol / mL (purchased from Shanghai Aladdin Chemical Co., Ltd.). After reacting at 120°C for 3 hours, the mixture was centrifuged and separated. The resulting solid was washed with deionized water and ethanol and dried to obtain hydroxyapatite powder.

[0083] (2) 0.5 parts by weight of the hydroxyapatite powder solid was added to a 50-part by weight dimethylformamide solution containing 8.23 ​​parts by weight of benzimidazole and 2.91 parts by weight of zinc nitrate (both purchased from Shanghai Aladdin Chemical Co., Ltd.) under stirring. The mixture was stirred for 2 hours (stirring speed of 1500 rpm) and then centrifuged (speed of 6000 rpm, temperature of 55℃, time of 3.5 hours) to obtain a solid powder. The obtained solid powder was washed with ethyl acetate and dried (drying temperature of 75℃, time of 2 hours) to obtain modified hydroxyapatite.

[0084] (3) 0.5 parts by weight of N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide and 10 parts by weight of modified hydroxyapatite solid were stirred and mixed in 50 parts by weight of ethanol for 10 hours (mixing pressure: 10.1 MPa, temperature: 25℃), and then centrifuged and dried (centrifugation speed: 5000 rpm, temperature: 60℃, time: 3 h) to obtain modified hydroxyapatite solid containing N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide. 5 parts by weight of modified hydroxyapatite solid were mixed with 70 parts by weight of bisphenol A epoxy resin (purchased from the Institute of Marine Chemistry) and stirred. During stirring, 25 parts by weight of triethylenetetramine curing agent (purchased from Aladdin Reagent) were added. The resulting mixture was subjected to vacuum degassing treatment (vacuum pressure -0.05MPa, temperature 28℃) to obtain composite anti-seepage coating S1.

[0085] Example 2

[0086] (1) 3.45 parts by weight of NH4H2PO4 (purchased from Sinopharm Chemical Reagent Co., Ltd.) and 2.2 parts by weight of Ca(NO3)2 (purchased from Sinopharm Chemical Reagent Co., Ltd.) were added to 85 parts by weight of deionized water and dissolved and then ultrasonically dispersed. The resulting dispersion mixture was added to 20 parts by weight of urea aqueous solution with a concentration of 0.008 mol / mL (purchased from Shanghai Aladdin Chemical Co., Ltd.). After reacting at 120°C for 4 hours, the mixture was centrifuged and separated. The resulting solid was washed with deionized water and ethanol and dried to obtain hydroxyapatite powder.

[0087] (2) 0.5 parts by weight of the hydroxyapatite powder solid was added to a 48-part by weight dimethylformamide solution containing 8.24 parts by weight of benzimidazole and 2.98 parts by weight of zinc nitrate (both purchased from Sinopharm Chemical Reagent Co., Ltd.) under stirring. The mixture was stirred for 1.5 hours (stirring speed of 1600 rpm) and then centrifuged (speed of 7000 rpm, temperature of 60℃, time of 3 hours) to obtain a solid powder. The obtained solid powder was washed with ethyl acetate and dried to obtain modified hydroxyapatite.

[0088] (3) 0.5 parts by weight of N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide and 12 parts by weight of modified hydroxyapatite solid were stirred and mixed in 50 parts by weight of ethanol for 9 hours (mixing pressure was 10.5 MPa and temperature was 25 °C), and then centrifuged and dried (centrifugation speed was 6500 rpm, temperature was 60 °C and time was 5 h) to obtain modified hydroxyapatite solid containing N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide. Five parts by weight of modified hydroxyapatite solid were mixed with 65 parts by weight of bisphenol F epoxy resin (purchased from Nan Ya Chemical Co., Ltd., Taiwan) and stirred. During the stirring process, 30 parts by weight of diethylenetriamine curing agent (Jinan Chuangshi Chemical Co., Ltd.) were added. The resulting mixture was then subjected to vacuum degassing treatment (vacuum pressure -0.05 MPa, temperature 28℃) to obtain composite anti-seepage coating S2.

[0089] Example 3

[0090] (1) 3.45 parts by weight of NH4H2PO4 (purchased from Sinopharm Chemical Reagent Co., Ltd.) and 2.7 parts by weight of Ca(NO3)2 (purchased from Sinopharm Chemical Reagent Co., Ltd.) were added to 86 parts by weight of deionized water and dissolved and then ultrasonically dispersed. The resulting dispersion mixture was added to 20 parts by weight of urea aqueous solution with a concentration of 0.0085 mol / mL (purchased from Shanghai Aladdin Chemical Co., Ltd.). After reacting fully at 125°C for 3 hours, the mixture was centrifuged and separated. The resulting solid was washed with deionized water and ethanol and dried to obtain hydroxyapatite powder.

[0091] (2) 0.5 parts by weight of the hydroxyapatite powder solid was added to a 52-part by weight dimethylformamide solution containing 8.23 ​​parts by weight of benzimidazole and 2.95 parts by weight of zinc nitrate (both purchased from Shanghai Aladdin Chemical Co., Ltd.) under stirring. The mixture was stirred for 2 hours (stirring speed of 1700 rpm) and then centrifuged (speed of 7000 rpm, temperature of 65℃, time of 3 min) to obtain a solid powder. The obtained solid powder was washed with dimethylformamide and dried to obtain modified hydroxyapatite.

[0092] (3) 0.5 parts by weight of N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide and 11 parts by weight of modified hydroxyapatite solid were stirred and mixed in 50 parts by weight of ethanol for 11 hours (mixing pressure: 10.2 MPa, temperature: 26℃), and then centrifuged and dried (centrifugation speed: 7000 rpm, temperature: 60℃, time: 4 h) to obtain modified hydroxyapatite solid containing N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide. 5 parts by weight of modified hydroxyapatite solid were mixed with 70 parts by weight of phenolic epoxy resin (purchased from Shandong Lehua Chemical) and stirred. During stirring, 25 parts by weight of triethylenetetramine curing agent (purchased from Aladdin Reagent) were added. The resulting mixture was subjected to vacuum degassing treatment (vacuum pressure -0.05MPa, temperature 28℃) to obtain composite anti-seepage coating S3.

[0093] Example 4

[0094] The method of Example 1 was followed, except that in step (3) of preparing the modified hydroxyapatite solid containing N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide, the modified hydroxyapatite was 5 parts by weight, and the composite anti-seepage coating S4 was obtained in the same way.

[0095] Example 5

[0096] The method of Example 1 was followed, except that in step (3) of preparing the modified hydroxyapatite solid containing N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide, the modified hydroxyapatite was 15 parts by weight, and the composite anti-seepage coating S5 was obtained in the same way.

[0097] Example 6

[0098] The procedure was carried out according to Example 1, except that the fluorescent probe molecule N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide was replaced with the same amount of N-(2-thiazolyl)-4-(1-piperidinyl)-1,8-naphthalimide, and the composite anti-seepage coating S6 was obtained in the same manner.

[0099] Example 7

[0100] The procedure was carried out according to Example 1, except that the fluorescent probe molecule N-[4-bis(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide was replaced with the same amount of N-(2-pyridinyl)-4-(1-piperidinyl)-1,8-naphthalimide, and the composite anti-seepage coating S7 was obtained in the same manner.

[0101] Comparative Example 1

[0102] The procedure was carried out according to Example 1, except that unmodified hydroxyapatite was used.

[0103] 0.5 parts by weight of N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide and 10 parts by weight of hydroxyapatite solid were stirred and mixed in 50 parts by weight of ethanol for 10 hours (mixing pressure: 10.1 MPa, temperature: 25°C), and then centrifuged and dried (centrifugation speed: 5000 rpm, temperature: 60°C, time: 3 h) to obtain hydroxyapatite solid containing N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide. 5 parts by weight of hydroxyapatite solid were mixed with 70 parts by weight of bisphenol A epoxy resin (purchased from the Institute of Marine Chemistry) and stirred. During stirring, 25 parts by weight of triethylenetetramine curing agent (purchased from Aladdin Reagent) were added. The resulting mixture was subjected to vacuum degassing treatment (vacuum pressure: -0.05 MPa, temperature: 28°C) to obtain composite anti-seepage coating D1.

[0104] Comparative Example 2

[0105] The method of Example 1 was followed, except that in step (3) of preparing the modified hydroxyapatite solid containing N-[4-bis(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide, the modified hydroxyapatite was 2 parts by weight, and the composite anti-seepage coating D2 was obtained in the same way.

[0106] Comparative Example 3

[0107] The method of Example 1 was followed, except that in step (3) of preparing the modified hydroxyapatite solid containing N-[4-bis(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide, the modified hydroxyapatite was 20 parts by weight, and the composite anti-seepage coating D3 was obtained in the same way.

[0108] Comparative Example 4

[0109] 1.0 g of aniline trimer and 1.0 g of graphene (purchased from Ningbo Moxi Technology Co., Ltd.) were dispersed in 1.0 L of toluene solution and ultrasonically dispersed for 1 hour to obtain a graphene dispersion. The graphene content in toluene reached 1 g / L after modification with aniline trimer. The graphene dispersion was added to 45 g of epoxy resin (model E44, purchased from Jiangsu Wujiang Heli Resin Factory), and mixed to obtain mixture A. Then, 2 g of leveling agent, 4 g of defoamer, 2 g of anti-settling agent, and 45 g of polyamide curing agent were added to mixture A in sequence, and stirred evenly to obtain composite anti-seepage coating D4.

[0110] Comparative Example 5

[0111] Disperse 3g of copper nitrate in 100mL of deionized water, dissolve evenly, and pour into a round-bottom flask. Disperse 0.2g of terephthalic acid in 100mL of deionized water, dissolve evenly, and pour into the same round-bottom flask to obtain a mixture. Add 1mL of 1M sodium hydroxide solution to the mixture. Place the round-bottom flask containing the mixture in an oil bath. Stir at 800r / min and set the oil bath temperature to 50℃. After stirring for 5h, centrifuge the resulting suspension at 5000r / min for 5min. Dry the resulting solid in a 50℃ oven for 30h to obtain copper ion organic framework nanomaterials. Add 2wt% organic framework nanomaterials to polyurethane resin and mix evenly. Then place the mixture in a vacuum oven at -0.05MPa for 20min to obtain a resin mixture. The above resin mixture was coated on the surface of carbon steel and cured at room temperature for 5 hours, and then cured in an oven at 60°C for 15 hours to obtain a corrosion self-diagnostic coating based on ion exchange. The thickness of the cured coating was 40 μm, and the composite anti-seepage coating D5 was obtained.

[0112] Comparative Example 6

[0113] Precursor solution synthesis: Polymer 1, Polymer 2, Solvent 1, Solvent 2, and copper nitrate were weighed in a mass ratio of 0.5:0.5:5:5:1. 0.5 g of polyvinyl butyral and 0.5 g of polyvinylpyrrolidone were added to a mixed solution of 5 mL ethanol and 5 mL N,N-dimethylformamide. The mixture was stirred at 400 rpm for 24 hours at 25°C. Then, 1 g of copper nitrate was added, and the mixture was stirred at 400 rpm for 10 hours at 25°C. Electrospinning synthesis: Tin foil was fixed to a roller receiver of appropriate size. The syringe containing the precursor solution was installed, and the power was turned on for electrospinning. The translation distance was set to 60 mm, the front stop of the injection device was set to zero, the syringe capacity was 5 mL, the positive voltage was set to 25 kV, the negative voltage to 4 kV, the injection rate to 0.08 mm / min, the receiving rate to 100 rpm, the translation speed to 40 mm / min, and the receiving distance to 20 cm. After spinning for 3 hours, nanofiber filler PVB / PVP-Cu2(OH)3NO3 can be obtained. The obtained nanofiber filler is mixed with mixed epoxy resin at a thickness ratio of 1:5, coated on the surface of a metal substrate, and dried at room temperature for 72 hours to obtain composite anti-seepage coating D6.

[0114] Test Example 1

[0115] The obtained intelligent anti-seepage coatings S1-S7 and coatings D1-D6 were drop-coated onto Q235 steel plates, and the coatings were applied to the Q235 steel plates with a cured thickness of 100 micrometers using a bar coating machine. After curing at room temperature for 10 hours and at 60℃ for 5 hours, the water resistance time of the coating formed by the coatings was tested according to the test method described in GB / T16777-2008. The results are shown in Table 1.

[0116] Table 1

[0117] Water resistance time / h S1 1800 S2 1800 S3 1750 S4 1400 S5 1430 S6 1600 S7 1580 D1 1020 D2 1020 D3 1050 D4 700 D5 600 D6 1100

[0118] Test Example 2

[0119] The obtained intelligent anti-seepage coatings S1-S7 and D1-D6 were drop-coated onto Q235 steel plates, and then coated onto the Q235 steel plates with a rod coating machine to achieve a cured coating thickness of 100μm. After curing at room temperature for 10 hours and at 60℃ for 5 hours, the oil leakage resistance of the coating was tested according to the test method described in GB / T16777-2008, except that the test medium water was replaced with simulated ethanol gasoline (the composition ratio refers to the EU standard EN13160-7-2003). The results are shown in Table 2.

[0120] Table 2

[0121] Oil leakage resistance time / h S1 1300 S2 1200 S3 1250 S4 950 S5 930 S6 1100 S7 1080 D1 550 D2 600 D3 630 D4 550 D5 400 D6 350

[0122] Test Example 3

[0123] The obtained intelligent anti-seepage coatings S1-S7 and coatings D1-D6 were drop-coated onto copper foil, and the coatings were applied to the copper foil with a rod coating machine to achieve a coating thickness of 50 μm after curing. After curing at room temperature for 10 h and at 60 °C for 5 h, the samples were used to test the corrosion resistance of the samples according to the method of GB / T1771-2007 for the determination of neutral salt spray resistance of paints and varnishes. The results are shown in Table 3.

[0124] Table 3

[0125] Salt spray corrosion resistance time / h S1 4200 S2 4500 S3 4300 S4 4000 S5 3900 S6 4100 S7 4000 D1 2000 D2 2900 D3 3000 D4 2800 D5 1400 D6 1800

[0126] Test Example 4

[0127] The obtained intelligent anti-seepage coatings S1-S7 and D1-D6 were drop-coated onto 13 identical Q235 steel plates. A rod coating machine was used to apply the coatings to the Q235 steel plates to a cured thickness of 5 μm. After curing at room temperature for 10 hours and then at 60°C for 5 hours, the 13 coated steel plates were placed in 13 identical beakers containing 3.5 wt% NaCl solution. After immersion for 6 hours, no significant changes were observed in the steel plates coated with D1-D6, while the steel plates coated with S1-S7 showed obvious fluorescence under dark conditions, with the fluorescence intensity increasing with the degree of corrosion. After another 6 hours of immersion, the fluorescence intensity of the corroded areas on the steel plates coated with S1-S7 continued to increase, and red marks appeared on the surface of the steel plates coated with D5. This indicates that the anti-seepage coatings S1-S7 prepared according to the method described in this invention have a self-diagnostic function for metal corrosion, and compared to the D5 coating, the sensitivity of corrosion self-diagnosis is higher. Furthermore, compared to the anti-seepage coating containing hydroxyapatite grafted with a molecular sieve imidazole framework described in this invention, the anti-seepage coating D1 containing pure hydroxyapatite is more likely to release fluorescent molecular probes prematurely during the coating's service life, causing them to lose activity and thus failing to achieve the self-diagnosis effect of corrosion.

[0128] Test Example 5

[0129] The obtained intelligent anti-seepage coatings S1-S7 and coatings D1-D6 were drip-coated onto Q235 steel plates, and the coatings were applied to the Q235 steel plates with a cured thickness of 100 micrometers using a bar coating machine. After curing at room temperature for 10 hours and at 60°C for 5 hours, the water resistance time of the coating formed by the coatings was tested according to the test method described in GB / T16777-2008. 100 hours after the start of the test, the same 50-micrometer wide and 1-centimeter long scratches were made on the coating surface of 13 steel plates using a scalpel, and the water resistance time of the coating formed by the coatings was tested again under the test conditions of GB / T16777-2008. The results are shown in Table 4.

[0130] Table 4

[0131] Water resistance time / h S1 1600 S2 1550 S3 1600 S4 1240 S5 1200 S6 1400 S7 1420 D1 520 D2 850 D3 790 D4 300 D5 420 D6 840

[0132] Comparative results from Test Examples 1 to 5 show that the intelligent anti-seepage coating prepared using the method described in this invention exhibits better resistance to corrosive media such as salt spray, water, and ethanol gasoline compared to existing technologies. It also demonstrates higher self-diagnostic sensitivity to corrosion and improved scratch healing efficiency. Furthermore, the molecular sieve imidazole framework on the hydroxyapatite surface is crucial for the self-healing function of the anti-seepage material.

[0133] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing a composite waterproof coating, characterized in that, This method Includes the following steps, 1) In the presence of a solvent, fluorescent probe molecules and modified hydroxyapatite are mixed and dried to obtain a solid product containing fluorescent probe molecules; 2) Mix the solid product described in step 1) with epoxy resin and curing agent to obtain a composite waterproof coating; The mass ratio of the fluorescent probe molecule to the modified hydroxyapatite is 1:5-35. The modified hydroxyapatite is hydroxyapatite grafted onto a molecular sieve imidazole framework material.

2. The method according to claim 1, wherein, In step 1), the mass ratio of the fluorescent probe molecule to the modified hydroxyapatite is 1:15-25.

3. The method according to claim 1, wherein, In step 1), the weight ratio of the modified hydroxyapatite to the solvent is 1:80-120.

4. The method according to claim 1, wherein, In step 1), the solvent is one or more of ethanol, diethyl ether, and phenol.

5. The method according to claim 4, wherein, In step 1), the solvent is ethanol.

6. The method according to claim 1, wherein, In step 1), the fluorescent probe molecule is one or more of N-[4-di(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthylimide, N-(2-thiazolyl)-4-(1-piperidinyl)-1,8-naphthylimide, and N-(2-pyridinyl)-4-(1-piperidinyl)-1,8-naphthylimide.

7. The method according to claim 6, wherein, In step 1), the fluorescent probe molecule is N-[4-bis(2-hydroxyethyl)aminophenyl]-4-(1-piperidinyl)-1,8-naphthalimide.

8. The method according to claim 1, wherein, In step 1), the mixing conditions include: a temperature of 20-30°C, a time of 8-12 hours, and a pressure of 8-12 MPa.

9. The method according to claim 8, wherein, The mixing conditions for step 1) include: a temperature of 24-26℃, a time of 9-11h, and a pressure of 10-11MPa.

10. The method according to claim 1, wherein, In step 1), the drying is centrifugal drying, and the drying conditions include: centrifugal speed of 4000-8000 rpm, temperature of 50-70℃, and time of 2-6 hours.

11. The method according to claim 10, wherein, The drying conditions include: a centrifugal speed of 5000-7000 rpm, a temperature of 55-65℃, and a time of 3-5 hours.

12. The method according to claim 1, wherein, The molecular sieve imidazole framework material is a metal-organic framework material.

13. The method according to claim 12, wherein, The molecular sieve imidazole framework material is the metal-organic framework material ZIF-7.

14. The method according to claim 1, wherein, The modified hydroxyapatite is obtained by contacting hydroxyapatite with benzimidazole and zinc nitrate in the presence of an organic solvent.

15. The method according to claim 14, wherein, The mass ratio of hydroxyapatite, benzimidazole, and zinc nitrate is 1:16-17:5-6.

16. The method of claim 14, wherein, The mass ratio of the hydroxyapatite to the organic solvent is 1:80-120.

17. The method according to claim 14, wherein, The organic solvent is dimethylformamide.

18. The method according to claim 1, wherein, In step 2), the mass ratio of the solid product, the epoxy resin, and the curing agent is 1:11-16:3-9.

19. The method according to claim 18, wherein, The mass ratio of the solid product, the epoxy resin, and the curing agent is 1:12-15.6:3.6-7.

20. The method according to claim 1, wherein, In step 2), the epoxy resin is one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, and phenolic epoxy resin.

21. The method according to claim 1, wherein, The curing agent is one or more of diethylenetriamine, triethylenetetramine, and hydroxyethylethylenediamine.

22. The method according to claim 1, wherein, The method also includes a step of vacuum degassing the mixed product after the mixing; The conditions for vacuum degassing include: a vacuum pressure of -0.03 to -0.08 MPa and a temperature of 25-35°C.

23. The composite anti-seepage coating prepared by the method of any one of claims 1-22.

24. A composite waterproof coating, characterized in that, The composite anti-seepage coating is prepared using the composite anti-seepage coating preparation method according to any one of claims 1-22 or the composite anti-seepage coating according to claim 23.

25. The composite waterproof coating according to claim 24, wherein, The composite anti-seepage coating is obtained by applying the composite anti-seepage coating to the surface of the substrate and then curing it.