Corrosion-resistant self-repairing polyurea coating material for ships and preparation method thereof
By combining modified zirconium hydrogen phosphate with polyurea and adding the quadruple hydrogen bonding curing agent UPy-IPDA-NH2, a self-healing polyurea coating material was prepared, which solved the problem of easy damage to traditional coatings, improved corrosion resistance and repair efficiency, and extended the service life of the coating.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHENYANG JUSHENG NEW MATERIAL TECH CO LTD
- Filing Date
- 2026-04-02
- Publication Date
- 2026-05-15
AI Technical Summary
Traditional anti-corrosion coatings are prone to micro-cracks or peeling on ship surfaces, leading to the penetration of corrosive media, which affects the protective effect. Moreover, repair is difficult and cannot provide long-term effective protection.
A self-healing polyurea coating material was prepared by mixing modified zirconium hydrogen phosphate with polyurea and adding UPy-IPDA-NH2, a curing agent with quadruple hydrogen bonds. The corrosion resistance was improved by modifying zirconium hydrogen phosphate, and the coating was rapidly repaired by utilizing the quadruple hydrogen bonds.
It significantly enhances the coating's resistance to scratches and damage, enabling rapid repair after damage, extending the coating's service life and reliability, and providing longer-lasting corrosion protection.
Smart Images
Figure CN122037745A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of self-healing anti-corrosion materials technology, specifically to a corrosion-resistant self-healing polyurea coating material for ships and its preparation method. The self-healing polyurea coating material manufactured using this preparation method is suitable for ship protection, especially for protection applications in high-salt corrosive environments. Background Technology
[0002] Ships operate in the marine environment for extended periods, and their surfaces are susceptible to corrosion from seawater, salt spray, microorganisms, and mechanical abrasion, leading to severe corrosion problems. Currently, ship protection mainly relies on traditional epoxy resin coatings, polyurethane coatings, and anti-corrosion primers. While these coatings offer some degree of corrosion protection, their corrosion resistance is limited, and they are prone to cracking and peeling over long-term use, resulting in a decline in protective effectiveness. To address this issue, anti-corrosion coatings have become a common protective measure. These coatings prevent direct contact between corrosive media and the ship's surface, thereby delaying or preventing corrosion. Common anti-corrosion coatings include epoxy resin coatings, polyurethane coatings, and acrylic coatings. These coatings have good corrosion resistance and are widely used in petrochemical, marine engineering, and construction industries. However, these traditional anti-corrosion coatings have several problems in use, mainly concerning the coating's durability, repair difficulty, and environmental adaptability.
[0003] Specifically, while traditional anti-corrosion coatings can effectively isolate corrosive media, they typically have some inherent defects. For example, during long-term service, coatings are prone to microcracks or peeling due to external impacts, temperature changes, mechanical wear, or environmental corrosion. This damage often allows corrosive media to penetrate the metal surface through the cracks, thereby compromising the coating's protective function and causing corrosion of the metal substrate. Therefore, the issue of coating damage repair has become one of the key factors limiting its long-term effectiveness. Summary of the Invention
[0004] This disclosure provides a method for preparing a corrosion-resistant, self-healing polyurea coating material for ships, comprising the following steps:
[0005] Prepare modified zirconium hydrogen phosphate, wherein the modified zirconium hydrogen phosphate comprises alkylated zirconium hydrogen phosphate;
[0006] Preparation of UP containing quadruple hydrogen bonds y Group curing agent UP y -IPDA-NH2; and
[0007] The modified zirconium hydrogen phosphate was mixed with polyurea in a certain proportion, and a curing agent IPDA and UP containing four hydrogen bonds were added in a certain proportion. yGroup curing agent UP y -IPDA-NH2, to obtain a self-healing polyurea coating material.
[0008] In some embodiments, the preparation of modified zirconium hydrogen phosphate includes the following steps:
[0009] Preparation of zirconium hydrogen phosphate using zirconium chloride and phosphoric acid solution; and
[0010] Modified zirconium hydrogen phosphate was obtained by modifying zirconium hydrogen phosphate with chloromethane.
[0011] In some embodiments, the preparation of zirconium hydrogen phosphate using zirconium chloride and phosphoric acid solution includes the following steps:
[0012] Zirconium chloride is added to deionized water and heated and stirred to dissolve it, forming a zirconium chloride solution.
[0013] A zirconium chloride solution was added to a phosphoric acid solution, and the reaction was carried out with stirring in a fume hood to obtain the first reactant; and
[0014] The first reactant was centrifuged, washed with deionized water, and dried to obtain zirconium hydrogen phosphate powder.
[0015] In some embodiments, modifying zirconium hydrogen phosphate with chloromethane to obtain modified zirconium hydrogen phosphate includes the following steps:
[0016] Zirconium hydrogen phosphate solution was obtained by dissolving zirconium hydrogen phosphate in isopropanol solvent;
[0017] Chloromethane was added to the zirconium hydrogen phosphate solution, and the reaction was carried out with stirring in a fume hood to obtain a second reactant.
[0018] The second reactant was centrifuged, washed with deionized water, and dried to obtain modified zirconium hydrogen phosphate powder.
[0019] In some embodiments, UP containing quadruple hydrogen bonds is prepared. y Group curing agent UP y -IPDA-NH2 includes the following steps:
[0020] The intermediate UP was obtained by reacting 2-amino-4-hydroxy-6-methylpyrimidine with N,N'-carbonyldiimidazole. y -CDI; and
[0021] UP the intermediate y -CDI reacts with curing agent IPDA to produce UP containing four hydrogen bonds. y Group curing agent UP y -IPDA-NH2.
[0022] In some embodiments, intermediate UP is obtained by reacting 2-amino-4-hydroxy-6-methylpyrimidine with N,N'-carbonyldiimidazole. y -CDI includes the following steps:
[0023] 2-Amino-4-hydroxy-6-methylpyrimidine and N,N'-carbonyldiimidazole were dispersed in dimethyl sulfoxide solvent, and a solid product was obtained by stirring and filtration.
[0024] The solid product was washed and dried to obtain the intermediate UP. y -CDI.
[0025] In some embodiments, the intermediate UP y -CDI reacts with curing agent IPDA to produce UP containing four hydrogen bonds. y Group curing agent UP y -IPDA-NH2 includes the following steps:
[0026] UP the intermediate y -CDI and curing agent IPDA are mixed and then added to n-hexane and stirred to obtain a mixture; and
[0027] The lower layer solution of the mixture was dissolved in dichloromethane, and the product was obtained by washing, drying, rotary evaporation, and vacuum drying. y Group curing agent UP y -IPDA-NH2.
[0028] In some embodiments, the modified zirconium hydrogen phosphate is mixed with polyurea in a certain proportion to form a composite material, and a curing agent IPDA and a UP containing four hydrogen bonds are added in a certain proportion. y Group curing agent UP y The process of obtaining a self-healing polyurea coating using IPDA-NH2 includes the following steps:
[0029] The modified zirconium hydrogen phosphate was mixed with polyurea in a certain proportion and then subjected to ultrasonic treatment to obtain a composite material.
[0030] Mix curing agent IPDA with UP containing quadruple hydrogen bonds in a specific ratio. y Group curing agent UP y -IPDA-NH2 is used to obtain a curing agent mixture;
[0031] The composite material and curing agent mixture are mixed in xylene solvent in a certain proportion, and the mixture is stirred, degassed, evaporated, and heated to obtain the self-healing polyurea coating material.
[0032] In some embodiments, the curing agent IPDA reacts with UP containing quadruple hydrogen bonds. yGroup curing agent UP y -IPDA-NH2 are mixed in a molar ratio of 8:2.
[0033] This disclosure provides some embodiments of a corrosion-resistant, self-healing polyurea coating material for ships, which is manufactured using the preparation method described in the foregoing embodiments.
[0034] Compared with related technologies, the above-described solutions of this disclosure have at least the following beneficial effects:
[0035] This disclosure discloses a self-healing polyurea coating material for marine applications, prepared by mixing modified zirconium hydrogen phosphate with polyurea and adding a curing agent with quadruple hydrogen bonds. The introduction of modified zirconium hydrogen phosphate enhances the corrosion resistance of the coating material, effectively preventing the penetration of corrosive media and providing longer-lasting protection. At the same time, the addition of modified zirconium hydrogen phosphate gives the coating material stronger mechanical properties, improving its scratch and damage resistance, making it more reliable in harsh environments. Furthermore, the use of quadruple hydrogen bond repair technology enables the coating to repair itself quickly after damage, significantly enhancing the coating's service life and reliability. Attached Figure Description
[0036] Figure 1 A flowchart illustrating a method for preparing a corrosion-resistant, self-healing polyurea coating material for ships according to some embodiments of this disclosure is shown;
[0037] Figure 2 for Figure 1 A detailed flowchart of step S100;
[0038] Figure 3 for Figure 2 The detailed flowchart of step S110;
[0039] Figure 4 for Figure 2 The detailed flowchart of step S120;
[0040] Figure 5 for Figure 1 The detailed flowchart of step S200;
[0041] Figure 6 for Figure 5 The detailed flowchart of step S210;
[0042] Figure 7 for Figure 5 The detailed flowchart of step S220;
[0043] Figure 8 for Figure 1 The detailed flowchart of step S300. Detailed Implementation
[0044] To make the objectives, technical solutions, and advantages of this disclosure clearer, the disclosure will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.
[0045] The terminology used in the embodiments of this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure. The singular forms “a,” “the,” and “the” as used in the embodiments of this disclosure and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.
[0046] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.
[0047] It should be understood that although the terms first, second, third, etc., may be used to describe structures in the embodiments of this disclosure, these structures should not be limited to these terms. These terms are only used to distinguish different structures. For example, without departing from the scope of the embodiments of this disclosure, a first component may also be referred to as a second component, and similarly, a second component may also be referred to as a first component.
[0048] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”
[0049] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.
[0050] This disclosure provides a method for preparing a corrosion-resistant, self-healing polyurea coating material for ships, comprising the following steps: preparing modified zirconium hydrogen phosphate, wherein the modified zirconium hydrogen phosphate includes alkylated zirconium hydrogen phosphate; preparing UP containing quadruple hydrogen bonds. y Group curing agent UP y -IPDA-NH2; and the modified zirconium hydrogen phosphate and polyurea are mixed in a certain proportion, and a curing agent IPDA and UP containing four hydrogen bonds are added in a certain proportion. y Group curing agent UP y -IPDA-NH2, to obtain a self-healing polyurea coating material.
[0051] This disclosure discloses a self-healing polyurea coating material for marine applications, prepared by mixing modified zirconium hydrogen phosphate with polyurea and adding a curing agent with quadruple hydrogen bonds. The introduction of modified zirconium hydrogen phosphate enhances the corrosion resistance of the coating material, effectively preventing the penetration of corrosive media and providing longer-lasting protection. At the same time, the addition of modified zirconium hydrogen phosphate gives the coating material stronger mechanical properties, improving its scratch and damage resistance, making it more reliable in harsh environments. Furthermore, the use of quadruple hydrogen bond repair technology enables the coating to repair itself quickly after damage, significantly enhancing the coating's service life and reliability.
[0052] The optional embodiments of this disclosure are described in detail below with reference to the accompanying drawings.
[0053] Figure 1 A flowchart illustrating a method for preparing a corrosion-resistant, self-healing polyurea coating material for ships, as provided in some embodiments of this disclosure, is shown. Figure 1 As shown in some embodiments of this disclosure, a method for preparing a corrosion-resistant, self-healing polyurea coating material for ships is provided. The preparation method includes the following steps:
[0054] S100: Prepare modified zirconium hydrogen phosphate, wherein the modified zirconium hydrogen phosphate includes alkylated zirconium hydrogen phosphate;
[0055] S200: Preparation of UP containing quadruple hydrogen bonds y Group curing agent UP y -IPDA-NH2; and
[0056] S300: The modified zirconium hydrogen phosphate is mixed with polyurea in a certain proportion, and IPDA curing agent and UP containing four hydrogen bonds are added in a certain proportion. y Group curing agent UP y -IPDA-NH2, to obtain a self-healing polyurea coating material.
[0057] The above preparation method includes the preparation of modified zirconium hydrogen phosphate and self-healing polyurea elastomer. The self-healing polyurea coating material prepared by this method is applied to the metal surface by spraying or spin coating processes, and cured at room temperature for 48 hours to finally form a composite coating with excellent corrosion resistance and self-healing ability. The above preparation method improves the corrosion resistance of the coating by introducing modified zirconium hydrogen phosphate and achieves rapid repair of the coating after damage by utilizing quadruple hydrogen bond repair technology, significantly enhancing the service life and reliability of the coating.
[0058] Figure 2 for Figure 1 A detailed flowchart of step S100 is provided in some embodiments, such as... Figure 2 As shown, step S100: the preparation of modified zirconium hydrogen phosphate includes the following steps:
[0059] S110: Preparation of zirconium hydrogen phosphate using zirconium chloride and phosphoric acid solution;
[0060] Specifically, zirconium hydrogen phosphate is obtained by reacting zirconium chloride with phosphoric acid, with the molecular formula Zr(HPO4)2.
[0061] S120: Modified zirconium hydrogen phosphate is obtained by modifying zirconium hydrogen phosphate with chloromethane.
[0062] Specifically, zirconium hydrogen phosphate is modified using chloromethane. Chloromethane reacts with the phosphate groups on the surface of zirconium hydrogen phosphate to generate alkylated zirconium hydrogen phosphate, namely methyl zirconium hydrogen phosphate Zr(OH)(HPO4)(OCH3).
[0063] Figure 3 for Figure 2 A detailed flowchart of step S110 is provided in some embodiments, such as... Figure 3 As shown, step S110: the preparation of zirconium hydrogen phosphate using zirconium chloride and phosphoric acid solution includes the following steps:
[0064] S111: Add zirconium chloride to deionized water, heat and stir to dissolve and form a zirconium chloride solution;
[0065] Specifically, weigh an appropriate amount of zirconium chloride and add it to an appropriate amount of deionized water. Under the condition of heating to the set temperature, stir slowly to dissolve it and obtain a zirconium chloride solution.
[0066] S112: Zirconium chloride solution is added to phosphoric acid solution, and the reaction is carried out with stirring in a fume hood to obtain the first reactant;
[0067] Specifically, the dissolved zirconium chloride solution is slowly poured into the phosphoric acid solution while continuously stirring. The reaction is carried out in a fume hood, and a cooling device is used to capture hydrogen chloride gas to prevent leakage of toxic gases, resulting in the formation of zirconium hydrogen phosphate precipitate, which is the first reactant. The molar ratio of zirconium chloride to phosphoric acid is 1:2, meaning 1 mol of zirconium chloride reacts with 2 mol of phosphoric acid.
[0068] S113: The first reactant is centrifuged, washed with deionized water, and dried to obtain zirconium hydrogen phosphate powder.
[0069] Specifically, the first reactant is subjected to centrifugation, washing with deionized water, and other filtration operations to remove impurities, and then transferred to an oven for drying to obtain zirconium hydrogen phosphate powder.
[0070] Figure 4 for Figure 2 A detailed flowchart of step S120 is provided in some embodiments, such as... Figure 2 As shown, step S120: Modifying zirconium hydrogen phosphate using chloromethane to obtain modified zirconium hydrogen phosphate includes the following steps:
[0071] S121: Zirconium hydrogen phosphate solution is obtained by dissolving zirconium hydrogen phosphate in isopropanol solvent;
[0072] Specifically, zirconium hydrogen phosphate powder is dissolved in isopropanol solution to form zirconium hydrogen phosphate solution.
[0073] S122: Chloromethane is added to the zirconium hydrogen phosphate solution, and the reaction is carried out with stirring in a fume hood to obtain a second reactant;
[0074] Specifically, excess chloromethane is added to an isopropanone solution containing dissolved zirconium hydrogen phosphate, and the mixture is continuously stirred to generate a modified zirconium hydrogen phosphate precipitate, which is the second reactant. For example, chloromethane can be directly introduced into the isopropanone solution containing dissolved zirconium hydrogen phosphate by bubbling, or chloromethane can be first dissolved in a solvent to form a chloromethane solution, such as a saturated chloromethane solution, and then added to the isopropanone solution containing dissolved zirconium hydrogen phosphate.
[0075] S123: The second reactant is centrifuged, washed with deionized water, and dried to obtain modified zirconium hydrogen phosphate powder.
[0076] Specifically, the second reactant is subjected to centrifugation, washing with deionized water, and other filtration operations to remove impurities, and then transferred to an oven for drying to obtain modified zirconium hydrogen phosphate powder.
[0077] Figure 5 for Figure 1 A detailed flowchart of step S200 is provided in some embodiments, such as... Figure 5 As shown, step S200: Preparation of UP containing four hydrogen bondsy Group curing agent UP y -IPDA-NH2 includes the following steps:
[0078] S210: Intermediate UP was obtained by reacting 2-amino-4-hydroxy-6-methylpyrimidine with N,N'-carbonyldiimidazole. y -CDI;
[0079] S220: UP the intermediate y -CDI reacts with curing agent IPDA to produce UP containing four hydrogen bonds. y Group curing agent UP y -IPDA-NH2.
[0080] Figure 6 for Figure 5 A detailed flowchart of step S210 is provided in some embodiments, such as... Figure 6 As shown, step S210: reacting 2-amino-4-hydroxy-6-methylpyrimidine with N,N'-carbonyldiimidazole to obtain intermediate UP. y -CDI includes the following steps:
[0081] S211: 2-Amino-4-hydroxy-6-methylpyrimidine and N,N'-carbonyldiimidazole are dispersed in dimethyl sulfoxide solvent, and a solid product is obtained by stirring and filtration.
[0082] Specifically, the molar ratio of 2-amino-4-hydroxy-6-methylpyrimidine to N,N'-carbonyldiimidazole is 2:3. The two are dispersed and dissolved in dimethyl sulfoxide solvent, stirred at high temperature, and then filtered and purified to obtain a solid product.
[0083] S212: Wash and dry the solid product to obtain the intermediate UP. y -CDI.
[0084] Specifically, the solid product is washed multiple times with cold acetone and dried under vacuum to obtain intermediate UP. y -CDI.
[0085] Figure 7 for Figure 5 A detailed flowchart of step S220 is provided in some embodiments, such as... Figure 7 As shown, step S200: the intermediate UP y -CDI reacts with curing agent IPDA to produce UP containing four hydrogen bonds. y Group curing agent UP y -IPDA-NH2 includes the following steps:
[0086] S221 will UP the intermediate y-CDI is mixed with curing agent IPDA and then added to n-hexane and stirred to obtain a mixture;
[0087] Specifically, the intermediate UP y -CDI, dissolved in curing agent IPDA (isophoretic diamine), intermediate UP y The molar ratio of CDI to curing agent IPDA is 1:10. Subsequently, hexane is added and stirred thoroughly.
[0088] S222: The lower layer solution of the mixture is dissolved in dichloromethane, and the product is obtained by washing, drying, rotary evaporation, and vacuum drying. y Group curing agent UP y -IPDA-NH2.
[0089] Specifically, the lower layer of the mixture is dissolved in dichloromethane and thoroughly washed with brine and deionized water. The mixture is then dried with Na₂SO₄ and the dichloromethane is removed by rotary evaporation. Finally, the mixture is dried under vacuum to obtain UP containing four hydrogen bonds. y Group curing agent UP y -IPDA-NH2.
[0090] Figure 8 for Figure 1 A detailed flowchart of step S300 is provided in some embodiments, such as... Figure 8 As shown, step S300: The modified zirconium hydrogen phosphate and polyurea are mixed in a certain proportion to form a composite material, and a curing agent IPDA and a UP containing four hydrogen bonds are added in a certain proportion. y Group curing agent UP y The process of obtaining a self-healing polyurea coating using IPDA-NH2 includes the following steps:
[0091] S310: The modified zirconium hydrogen phosphate and polyurea are mixed in a certain proportion and ultrasonically treated to obtain a composite material;
[0092] Modified zirconium hydrogen phosphate and polyurea were mixed at a mass ratio of 1:20, and ultrasonic treatment technology was used to ensure that the modified zirconium hydrogen phosphate was uniformly dispersed in the polyurea, thus ensuring the uniformity of the coating material.
[0093] S320: A proportionally mixed curing agent IPDA and UP containing quadruple hydrogen bonds. y Group curing agent UP y -IPDA-NH2 is used to obtain a curing agent mixture;
[0094] Specifically, the curing agent IPDA and UP containing quadruple hydrogen bonds y Group curing agent UP yThe ratio of IPDA to NH2, i.e., the molar ratio, is 6:4 to 9:1, which is achieved by adjusting the ratio of the curing agent IPDA to UP containing quadruple hydrogen bonds. y Different self-healing polyurea elastomers can be prepared by varying the content ratio of the group-curing agent UPy-IPDA-NH2.
[0095] S330: The composite material and curing agent mixture are mixed in xylene solvent in a certain proportion, and the self-healing polyurea coating material is obtained by stirring, degassing, evaporation and heat treatment.
[0096] Specifically, the composite material and curing agent mixture are thoroughly mixed and stirred in xylene solvent at a mass ratio of 10:1. The air bubbles in the mixture solution are removed using a vacuum drying oven. The solution is then applied to polytetrafluoroethylene (PTFE) and vacuum dried to ensure complete evaporation of the solvent. Finally, it is heated to obtain a self-healing polyurea elastomer, i.e., a self-healing polyurea coating material.
[0097] The self-healing polyurea coating material prepared using the method disclosed herein has significant advantages over traditional anti-corrosion coatings. Firstly, it possesses self-healing capabilities, automatically repairing damaged areas when microcracks or damage occur in the coating, restoring its anti-corrosion performance, and extending its service life. Specifically, this is achieved by embedding 2-ureido-4[1H]-pyrimidinone (UP) with four hydrogen bonds. y UP units endow materials with excellent self-healing properties. When the material is subjected to mechanical damage, UP y The material can restore its original structure through reversible hydrogen bonding interactions between units, achieving self-healing. Secondly, the introduction of modified zirconium hydrogen phosphate significantly improves the corrosion resistance of the coating, effectively preventing the penetration of corrosive media and providing longer-lasting protection. Finally, due to the addition of modified zirconium hydrogen phosphate, the material has stronger mechanical properties, improving the coating's scratch and damage resistance, making it more reliable in harsh environments.
[0098] The following provides specific examples and comparative studies of this disclosure.
[0099] Example 1
[0100] Example 1 provides a method for preparing a corrosion-resistant, self-healing polyurea coating material for ships, specifically including the following steps:
[0101] Step S100: Prepare modified zirconium hydrogen phosphate, wherein the modified zirconium hydrogen phosphate comprises alkylated zirconium hydrogen phosphate.
[0102] Specifically, 5g of zirconium chloride was added to 100ml of deionized water, heated to 60℃ and stirred continuously until dissolved. The zirconium chloride solution was then slowly poured into a 0.5mol / L phosphoric acid solution and stirred continuously for 2 hours to form zirconium hydrogen phosphate precipitate. The above reaction was carried out in a fume hood, and a cooling device was used to capture hydrogen chloride gas to prevent leakage of toxic gases.
[0103] The reactants were transferred to centrifuge tubes and centrifuged at 3000 rpm for 15 min. The zirconium hydrogen phosphate precipitate was then transferred to test tubes and washed repeatedly with deionized water. The precipitate was dried at 60°C to remove moisture, yielding a pale yellow zirconium hydrogen phosphate powder.
[0104] Weigh 5g of zirconium hydrogen phosphate and add it to 100ml of isopropanol solvent. Heat the solution to 60℃ and stir with a magnetic stirrer until the zirconium hydrogen phosphate is completely dissolved. Add 0.03mol of chloromethane to the isopropanol solution containing dissolved zirconium hydrogen phosphate and stir continuously for 2 hours. The above reactions are carried out in a fume hood.
[0105] The reactants were transferred to centrifuge tubes and centrifuged at 3000 rpm for 15 min. The modified zirconium hydrogen phosphate precipitate was then transferred to test tubes and washed repeatedly with deionized water. The precipitate was dried at 60°C for 12 h to remove moisture, yielding powdered modified zirconium hydrogen phosphate.
[0106] S200: Preparation of UP containing quadruple hydrogen bonds y Group curing agent UP y -IPDA-NH2;
[0107] Specifically, 15.0 g (0.12 mol) of 2-amino-4-hydroxy-6-methylpyrimidine and 29.187 g (0.18 mol) of N,N'-carbonyldiimidazole (CDI) were dispersed and dissolved in 500 mL of dimethyl sulfoxide (DMSO), and the mixture was stirred at 80 °C for 2 h. The solid product was then purified by filtration.
[0108] The solid product was washed three times with cold acetone and dried under vacuum at 30°C for 12 hours to obtain 21.82 g of a white powder, with a yield of 83%. The compound was named UP. y -CDI, also known as intermediate UP y -CDI.
[0109] 10.0 g, 0.0456 mol of intermediate UP y -CDI was mixed with 78.49 g of 0.456 mol of curing agent IPDA (isophoretic diamine) and stirred at 45 °C for 48 h. Subsequently, n-hexane at 0 °C was added and stirred thoroughly to obtain a mixture.
[0110] The lower layer of the mixture was then dissolved in 30 mL of dichloromethane (DCM) and thoroughly washed three times with 30 mL of brine and 30 mL of deionized water. The mixture was then dried with Na₂SO₄ and the dichloromethane was removed by rotary evaporation. Finally, the mixture was dried under vacuum overnight to obtain UP containing four hydrogen bonds. y Group curing agent UP y -IPDA-NH2.
[0111] S300: The modified zirconium hydrogen phosphate is mixed with polyurea in a certain proportion, and IPDA curing agent and UP containing four hydrogen bonds are added in a certain proportion. y Group curing agent UP y -IPDA-NH2, to obtain a self-healing polyurea coating material.
[0112] Specifically, modified zirconium hydrogen phosphate and polyurea are mixed at a mass ratio of 1:20. Ultrasonic treatment is used to ensure that the modified zirconium hydrogen phosphate is uniformly dispersed in the polyurea, ensuring the uniformity of the coating material and obtaining a uniform composite material.
[0113] The curing agent IPDA and UP containing quadruple hydrogen bonds are mixed in a 9:1 molar ratio. y Group curing agent UP y -IPDA-NH2 is used to obtain a curing agent mixture.
[0114] 4.5 g of the composite material and 0.452 g of the curing agent mixture, along with 150 mL of xylene solvent, were thoroughly mixed and stirred for 20 min. Air bubbles in the mixture were removed using a vacuum drying oven. The mixture was then applied to polytetrafluoroethylene (PTFE) and vacuum dried at 60 °C for 24 h to ensure complete solvent evaporation. Finally, it was heated at 80 °C for 24 h to obtain a self-healing polyurea elastomer, named NEU0.1.
[0115] Example 2:
[0116] The preparation method of the self-healing polyurea coating material in Example 2 is basically the same as that in Example 1, except that in step S300, the curing agent IPDA and UP containing four hydrogen bonds are mixed in a molar ratio of 8:2. y Group curing agent UP y -IPDA-NH2 was used to obtain a curing agent mixture. The self-healing polyurea elastomer prepared by the preparation method of Example 2 was named NEU0.2.
[0117] Example 3:
[0118] The preparation method of the self-healing polyurea coating material in Example 3 is basically the same as that in Example 1, except that in step S300, the curing agent IPDA and UP containing four hydrogen bonds are mixed in a molar ratio of 7:3. y Group curing agent UP y -IPDA-NH2 was used to obtain a curing agent mixture. The self-healing polyurea elastomer prepared by the preparation method of Example 3 was named NEU0.3.
[0119] Example 4:
[0120] The preparation method of the self-healing polyurea coating material in Example 4 is basically the same as that in Example 1, except that in step S300, the curing agent IPDA and UP containing four hydrogen bonds are mixed in a molar ratio of 6:4. y Group curing agent UP y -IPDA-NH2 was used to obtain a curing agent mixture. The self-healing polyurea elastomer prepared by the preparation method of Example 4 was named NEU0.4.
[0121] Comparative Example 1:
[0122] The preparation method of the self-healing polyurea coating material in the comparative example is basically the same as that in Example 1, except that in step S300, the curing agent mixture only uses IPDA curing agent and does not contain UP containing four hydrogen bonds. y Group curing agent UP y The polyurea elastomer prepared by the comparative method of -IPDA-NH2 is named NEP1.
[0123] As described above, in the method for preparing the self-healing polyurea coating material provided in this disclosure, different polyurea elastomers can be prepared by adding curing agent mixtures with different mixing ratios. Firstly, it completely avoids using UP containing quadruple hydrogen bonds. y Group curing agent UP y -IPDA-NH2, using only IPDA as the curing agent, corresponding to a ratio of 1, then changing the amount of IPDA added, adding different amounts of UP containing quadruple hydrogen bonds. y Group curing agent UP y -IPDA-NH2 curing agent, corresponding to Examples 1 to 4, yielded four different products with UP y Polyurea elastomers of the unit. For distinction, NEPx and NEUx are used here to name polyurea elastomers; NEP indicates a polyurea elastomer, and NEU indicates one with UP... y The unit is a polyurea elastomer, and "x" is used to distinguish different proportions of curing agent added.
[0124] The polyurea elastomers prepared by the preparation methods of Examples 1 to 4 and the comparative examples were tested respectively, and the test results are shown in Table 1.
[0125] Table 1
[0126]
[0127] As shown in Table 1, the glass transition temperatures (Tg) of NEP1, NEU0.1, NEU0.2, NEU0.3, and NEU0.4 are not significantly different, with elongation at break increasing sequentially, tensile strength decreasing sequentially, and recovery rate increasing sequentially. Although the NEU0.1 sample has the best tensile strength, its strength-elongation recovery only restores 68% of its initial state. This phenomenon is due to UP y This is due to insufficient addition of unit content. Limited self-healing ability cannot guarantee the stability and safety of the material during service. For the NEU0.2 sample, the self-healing efficiency was significantly improved, reaching approximately 89%, indicating that UP... y Increasing the unit content can improve the repair efficiency of the coating material. Furthermore, the repair efficiency of NEU0.3 and NEU0.4 samples reached over 90%, but their tensile strength was only half that of the NEU0.2 sample, or even lower. Based on the above test results, it can be confirmed that the polyurea elastomer of the NEU0.2 sample exhibits strong tensile strength, high elongation at break, and excellent self-healing properties, possessing the best overall performance.
[0128] To further verify the protective effect of the elastomer coating, EDS analysis was performed on the polyurea elastomers prepared by the preparation methods of Examples 1 to 4 and the comparative example after peeling and immersion. The analysis results are shown in Table 2, which reflects the atomic percentage of various elements in the polyurea elastomer.
[0129] Table 2
[0130]
[0131] As shown in Table 2, for samples NEP1, NEU0.1, NEU0.3, and NEU0.4, a large amount of corrosion products, such as iron oxide, were present on the metal surface at the scratches of the coating, indicating that the substrate had been severely corroded. This damage was irreparable, leading to the accumulation of corrosion products. For sample NEU0.2, a small amount of corrosion products were observed on its surface. This is early corrosion of the metal caused by the initial stage of damage repair, but it was significantly less than the other three coatings. This indicates that NEU0.2 did not experience significant penetration of the corrosive medium during immersion. This performance of NEU0.2 is attributed to the repair of micro-defects inside the coating by multiple hydrogen bonds and the reconstruction of the molecular shielding network. The complete molecular network of the coating has a good barrier effect, increasing the corrosion resistance of the coating and thus providing excellent corrosion protection for the metal under the coating.
[0132] This disclosure combines the curing agent IPDA with UP containing quadruple hydrogen bonds. y Group curing agent UP y When IPDA and NH2 are used synergistically in a suitable molar ratio, they can simultaneously construct two levels of crosslinking within the same network: an irreversible covalent backbone and reversible multi-point hydrogen bonds. Specifically, IPDA participates in the epoxy ring-opening reaction to form a dense and continuous covalent crosslinked network, endowing the material with the necessary initial strength, modulus, and durable shielding. y -IPDA-NH2 maintains network integrity by forming covalent bonds between -NH2 and epoxy, while its side chain UP y Groups spontaneously pair to form quadruple hydrogen bonds with a strength between covalent and ordinary hydrogen bonds. These bonds preferentially break and absorb energy under load, and rapidly reconstruct upon unloading or at room temperature, balancing toughness and rapid self-healing. When UP y If the content is too low, the sacrificial bond density is insufficient, limiting the repair efficiency and elongation. If the content is too high, it leads to sparse covalent crosslinking, decreased strength, and weakened shielding performance. Experiments have shown that NEU0.2 in Example 2 achieves a "mechanical-kinetic" balance between covalent and reversible crosslinking, matching the chain segment diffusion rate with the interfacial heavy bond rate. As a result, it achieves optimal comprehensive performance in terms of tensile strength, elongation at break, 89% self-healing efficiency within 10 min at room temperature, and long-term corrosion resistance.
[0133] Comparative Example 2:
[0134] The preparation method of the self-healing polyurea coating material in Comparative Example 2 is basically the same as that in Example 1, except that modified zirconium hydrogen phosphate is not added to the polyurea. The self-healing polyurea elastomer prepared by the preparation method of Comparative Example 2 is named PUA0.1.
[0135] Electrochemical impedance spectroscopy was performed on NEU0.1 in Example 1 and PUA0.1 in Comparative Example 2, with a test frequency range of 10 Hz.5 Up to 10 -2 The electrolyte was 3.5 wt% NaCl solution, the coating thickness was 50 ± 5 μm, and the immersion time was 50 days. The test data are shown in Tables 3 and 4 below, where Table 3 shows the change of low-frequency impedance modulus (Zf = 0.01 Hz) with immersion time, and Table 4 shows the Bode phase angle characteristic parameters.
[0136] Table 3
[0137]
[0138] Table 4
[0139]
[0140] Based on electrochemical impedance spectroscopy (EIS) data analysis, the polyurea coating NEU0.1 modified with chloromethane-modified zirconium hydrogen phosphate exhibits significantly superior corrosion resistance compared to the pure polyurea coating PUA0.1: in immersion tests in 3.5 wt% NaCl solution, the initial impedance value of the NEU0.1 coating reached 3.2 × 10⁻⁶. 9 Ω·cm 2 This is higher than PUA0.1's 2.1×10 9 Ω·cm 2 After 50 days of soaking, the NEU0.1 concentration still remained at 1.4 × 10⁻⁶. 9 Ω·cm 2 The high impedance (retention rate 43.75%), while PUA0.1 drops sharply to 5.3 × 10⁻⁶. 7 Ω·cm 2 (The retention rate was only 2.52%), and PUA0.1 showed a second time constant after 50 days, indicating that the corrosive medium had penetrated the coating and reached the metal substrate, while NEU0.1 maintained a single time constant and a low breakpoint frequency of 0.15 Hz, proving that the coating had good integrity. This performance improvement is mainly attributed to the "maze effect" generated by the ordered layered arrangement of chloromethane-modified zirconium hydrogen phosphate in the polyurea matrix, which extended the penetration path of the corrosive medium by 3 to 5 times. At the same time, the hydrogen bond interaction between the chloromethane group and the -NH group of polyurea improved the interfacial compatibility and reduced agglomeration and interfacial defects. In addition, the interlayer ion exchange capacity of zirconium hydrogen phosphate can capture corrosive ions such as Cl⁻, and the uniform dispersion of modified nanosheets also improved the coating density (porosity <5%). The synergistic effect of multiple mechanisms made the long-term protection capability of the NEU0.1 coating about 26 times better than that of PUA0.1.
[0141] Some embodiments of this disclosure also provide a corrosion-resistant self-healing polyurea coating material for ships, which is manufactured using the preparation method described in the foregoing embodiments.
[0142] The self-healing polyurea coating material prepared using the method for preparing corrosion-resistant self-healing polyurea coatings for ships provided in this disclosure has the following advantages:
[0143] By introducing modified zirconium hydrogen phosphate, the corrosion resistance of the coating material is improved, effectively preventing the penetration of corrosive media and providing longer-lasting protection. At the same time, the addition of modified zirconium hydrogen phosphate gives the coating material stronger mechanical properties, improves the coating's scratch resistance and damage resistance, and makes it more reliable in harsh environments.
[0144] Through UP y The material utilizes a hydrogen-bonded repair mechanism, enabling it to rapidly repair micro-damage such as scratches and cracks at room temperature. The repaired material not only restores its original shape but also maintains high mechanical properties. This self-healing function significantly extends the material's lifespan and reduces maintenance and replacement costs.
[0145] Polyurea elastomers exhibit high elongation and demonstrate high strength and ductility in tensile tests. Even after mechanical damage, the material can recover near-original mechanical properties, ensuring structural integrity during long-term use.
[0146] Polyurea elastomers exhibit excellent anti-corrosion performance in salt spray environments. Even after damage, the coating can still effectively prevent the penetration of corrosive media and protect the substrate from corrosion, indicating that it has good corrosion resistance in marine environments.
[0147] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems or apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.
[0148] The above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit it. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure.
Claims
1. A method for preparing a corrosion-resistant, self-healing polyurea coating material for ships, characterized in that, Includes the following steps: Prepare modified zirconium hydrogen phosphate, wherein the modified zirconium hydrogen phosphate comprises alkylated zirconium hydrogen phosphate; Preparation of UP containing quadruple hydrogen bonds y Group curing agent UP y -IPDA-NH2; and The modified zirconium hydrogen phosphate was mixed with polyurea in a certain proportion, and a curing agent IPDA and UP containing four hydrogen bonds were added in a certain proportion. y Group curing agent UP y -IPDA-NH2, to obtain a self-healing polyurea coating material.
2. The method for preparing the self-healing polyurea coating material according to claim 1, characterized in that, The preparation of modified zirconium hydrogen phosphate includes the following steps: Preparation of zirconium hydrogen phosphate using zirconium chloride and phosphoric acid solution; and Modified zirconium hydrogen phosphate was obtained by modifying zirconium hydrogen phosphate with chloromethane.
3. The method for preparing the self-healing polyurea coating material according to claim 2, characterized in that, The preparation of zirconium hydrogen phosphate using zirconium chloride and phosphoric acid solution includes the following steps: Zirconium chloride is added to deionized water and heated and stirred to dissolve it, forming a zirconium chloride solution. A zirconium chloride solution was added to a phosphoric acid solution, and the reaction was carried out with stirring in a fume hood to obtain the first reactant; and The first reactant was centrifuged, washed with deionized water, and dried to obtain zirconium hydrogen phosphate powder.
4. The method for preparing the self-healing polyurea coating material according to claim 2, characterized in that, The modified zirconium hydrogen phosphate is obtained by modifying zirconium hydrogen phosphate with chloromethane, which includes the following steps: Zirconium hydrogen phosphate solution was obtained by dissolving zirconium hydrogen phosphate in isopropanol solvent; Chloromethane was added to the zirconium hydrogen phosphate solution, and the reaction was carried out with stirring in a fume hood to obtain a second reactant. The second reactant was centrifuged, washed with deionized water, and dried to obtain modified zirconium hydrogen phosphate powder.
5. The method for preparing the self-healing polyurea coating material according to claim 1, characterized in that, Preparation of UP containing quadruple hydrogen bonds y Group curing agent UP y -IPDA-NH2 includes the following steps: The intermediate UP was obtained by reacting 2-amino-4-hydroxy-6-methylpyrimidine with N,N'-carbonyldiimidazole. y -CDI; and UP the intermediate y -CDI reacts with curing agent IPDA to produce UP containing four hydrogen bonds. y Group curing agent UP y -IPDA-NH2.
6. The method for preparing the self-healing polyurea coating material according to claim 5, characterized in that, The intermediate UP was obtained by reacting 2-amino-4-hydroxy-6-methylpyrimidine with N,N'-carbonyldiimidazole. y -CDI includes the following steps: 2-Amino-4-hydroxy-6-methylpyrimidine and N,N'-carbonyldiimidazole were dispersed in dimethyl sulfoxide solvent, and a solid product was obtained by stirring and filtration. The solid product was washed and dried to obtain the intermediate UP. y -CDI.
7. The method for preparing the self-healing polyurea coating material according to claim 5, characterized in that, UP the intermediate y -CDI reacts with curing agent IPDA to produce UP containing four hydrogen bonds. y Group curing agent UP y -IPDA-NH2 includes the following steps: UP the intermediate y -CDI and curing agent IPDA are mixed and then added to n-hexane and stirred to obtain a mixture; and The lower layer solution of the mixture was dissolved in dichloromethane, and the product was obtained by washing, drying, rotary evaporation, and vacuum drying. y Group curing agent UP y -IPDA-NH2.
8. The method for preparing the self-healing polyurea coating material according to claim 1, characterized in that, The modified zirconium hydrogen phosphate and polyurea are mixed in a certain proportion to form a composite material, and a curing agent IPDA and a UP containing four hydrogen bonds are added in a certain proportion. y Group curing agent UP y The process of obtaining a self-healing polyurea coating using IPDA-NH2 includes the following steps: The modified zirconium hydrogen phosphate was mixed with polyurea in a certain proportion and then subjected to ultrasonic treatment to obtain a composite material. Mix curing agent IPDA with UP containing quadruple hydrogen bonds in a specific ratio. y Group curing agent UP y -IPDA-NH2 is used to obtain a curing agent mixture; The composite material and curing agent mixture are mixed in xylene solvent in a certain proportion, and the mixture is stirred, degassed, evaporated, and heated to obtain the self-healing polyurea coating material.
9. The method for preparing the self-healing polyurea coating material according to claim 8, characterized in that, The curing agent IPDA and UP containing quadruple hydrogen bonds y Group curing agent UP y -IPDA-NH2 are mixed in a molar ratio of 8:
2.
10. A corrosion-resistant, self-healing polyurea coating material for ships, characterized in that, The self-healing polyurea coating material is manufactured using the preparation method described in any one of claims 1 to 9.