Method for preparing micron-flower-shaped structure super-hydrophobic membrane on rusty bronze surface
By using a combination method of pretreatment liquid and film forming liquid on the surface of rusted bronze, a micron-shaped structure superhydrophobic film was prepared, which solved the problem that the prior art was difficult to prepare a superhydrophobic film on the surface of rusted bronze, and significantly improved the corrosion resistance and self-cleaning ability of bronzeware.
Patent Information
- Application Number
- CN202510172404.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-17
- Publication Date
- 2025-04-08
AI Technical Summary
The prior art is difficult to directly prepare superhydrophobic films on the rusted bronze surface, which leads to the rapid increase in the oxygen and moisture content of bronzes in the environment, and it is difficult to effectively prevent irreversible corrosion and damage.
By preparing pretreatment liquid and film forming liquid, including components such as phenylatic acid, sodium hydroxide and stearic acid, the rust layer is first pretreated on the surface of the rusted bronze to activate the rust layer, and then a micron-shaped structure superhydrophobic film is formed on its surface.
Without changing the original appearance of rusted bronze, a micron-shaped structure superhydrophobic film with a contact angle of up to 154-158.5° was prepared, which significantly improved the corrosion resistance of rusted bronze and had self-cleaning properties to effectively prevent corrosion of environmental media.
Smart Images
Figure CN119776817A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of cultural relics protection, relates to metal surface treatment technology, and in particular to a method for preparing a micron flower-shaped super-hydrophobic film on a rusty bronze surface. Background Art
[0002] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention, and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.
[0003] Bronze is the earliest alloy in the history of metal smelting, usually containing elements such as tin or lead. The emergence of bronze ware has improved productivity and promoted the development of human society. At the same time, it has extremely high artistic value and records the rise and fall of different civilizations. However, due to the long-term burial of bronze ware in complex and diverse underground environments, the harmful rust layer on the surface of unearthed bronze ware has brought many difficulties to the preservation of cultural relics. The drastic changes in the environment after unearthed, especially the sharp increase in oxygen and moisture content in the environment, will cause irreversible damage to bronze ware, which is bronze disease. Therefore, it is necessary to carry out timely and effective anti-corrosion treatment on unearthed bronze ware.
[0004] Modifying a layer of super-hydrophobic film on the metal surface can significantly enhance the corrosion resistance of the metal, isolate moisture in the environment, and also have the advantages of anti-oxidation and self-cleaning. However, there are currently few literatures or reports on the preparation of super-hydrophobic films directly on rusty bronze surfaces. Due to the complex composition and morphology of the rust layer on the bronze surface, it is difficult to directly apply the existing preparation methods of super-hydrophobic films on metal surfaces on rusty bronze surfaces. Summary of the invention
[0005] The purpose of the present invention is to propose a method for preparing a micron flower-like super-hydrophobic film on the surface of rusty bronze in view of the above problems. The components of the pretreatment liquid and the film-forming liquid are simple and easy to prepare. A super-hydrophobic film can be prepared on the surface of the rusty bronze without almost changing the color of the rusty bronze. This super-hydrophobic film can effectively improve the corrosion resistance of the rusty bronze.
[0006] The specific technical solutions are as follows: On one hand, the present invention provides a method for preparing a micron flower-like structure super-hydrophobic film on a rusty bronze surface, comprising the following steps: S1. Prepare a pretreatment solution: the pretreatment solution includes trimesic acid, sodium hydroxide, and nitric acid, and the solvent is an organic solvent and water; prepare a film-forming solution: the required film-forming solution includes stearic acid, sodium hydroxide or nitric acid, and the solvent is an organic solvent; S2, immersing the rusted bronze in a pretreatment solution, wherein the solution temperature is 20-30°C during the immersion process; S3, take out the rusty bronze, rinse it with an organic solvent, and immerse it in a film-forming solution for 1 to 3 hours to prepare a super-hydrophobic film. The solution temperature during the immersion process is 20°C to 30°C; S4. After the film is formed, take out the rusty bronze, rinse it with organic solvent and blow it dry.
[0007] The composition and structure of the rust layer of rusty bronze are usually complex, so the influence of different rust layer compositions needs to be considered when selecting a protection plan. The present application can regulate the microscopic morphology of the rust layer surface after pretreatment by adding nitric acid and adjusting the pH of the pretreatment liquid. Different pH values are used for different rust layers to obtain better protection effects.
[0008] In the solvent of the pretreatment liquid in step S1, the organic solvent is an alcohol solvent, preferably ethanol.
[0009] The mass fraction of each substance in the pretreatment solution in step S1 is: 0.1-0.2% of trimesic acid, 0.06-0.18% of sodium hydroxide. The mass fraction of each substance in the film-forming solution is: 0.2-0.3% of stearic acid.
[0010] In step S1, the volume fraction of ethanol in the solvent of the pretreatment solution is 40-55%, and the pH is adjusted to 6.0-8.0 by nitric acid; the pH of the membrane-forming solution is adjusted to 5.0-6.0 by sodium hydroxide or nitric acid.
[0011] On the other hand, the present invention also provides a method for preparing a super-hydrophobic film on a rusty bronze surface and its application in the anti-corrosion of bronze artifacts.
[0012] Beneficial effects of the present invention: 1. The method of the present invention utilizes the coordination ability of trimesic acid and copper, first activates the rust layer on the surface of bronze, enhances its binding force with stearic acid, and then modifies the low surface energy substance of stearic acid to prepare a relatively rare micron flower-like structure super hydrophobic film without changing the original appearance of the rusted bronze; the micron flower-like structure can significantly increase the contact angle of water droplets by increasing the surface roughness, showing stronger hydrophobicity. It also has a certain self-cleaning performance, and water droplets can take away pollutants when rolling on the surface to keep the surface clean.
[0013] 2. The solution required for the present invention is simple in composition and convenient in processing conditions, and can be directly applied on the surface of rusted bronze. The prepared super-hydrophobic film has a contact angle of 154-158.5°, which can effectively isolate the corrosive medium in the environment, and its corrosion resistance is much higher than that of rusted bronze and rusted bronze treated only with film-forming liquid. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.
[0014] Figure 1 is the contact angle of a water drop on the rusted bronze surface with a superhydrophobic film; Figure 2 The SEM images of the rusted bronze surface under different treatment conditions; (a) the rusted bronze surface treated only with the film-forming solution, (b) the rusted bronze surface treated only with the pretreatment solution, (c) the rusted bronze surface treated with the pretreatment solution and then with the film-forming solution; Figure 3 Figure 2 is the AC impedance spectra of rusted bronze under different treatment conditions. The test solution is a 3.5wt.% NaCl deionized water solution. (a) The rusted bronze surface treated only with the film-forming solution, (b) The rusted bronze surface treated only with the pretreatment solution, and (c) The rusted bronze surface treated with the pretreatment solution and then with the film-forming solution. DETAILED DESCRIPTION
[0015] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.
[0016] Through a large number of experiments, the inventors found that after the rusty bronze was first treated with a pretreatment solution containing trimesic acid, the rust layer on the surface of the bronze could be activated to form a small amount of micron flower-like structure. Then, it was treated with a film-forming solution containing stearic acid to form a layer of micron flower-like structure super-hydrophobic film on the surface of the rust layer, and the color of the rust layer hardly changed before and after the treatment.
[0017] As is common knowledge in the field, the water contact angle of superhydrophobic films is usually greater than 150°, with low surface energy and a certain micro-nano structure. They can exhibit extremely strong hydrophobicity and self-cleaning ability and are widely used in anti-fouling, anti-icing, anti-corrosion and other fields.
[0018] Preparation of simulated rusted bronze samples: The bronze model used is QSn 6.5-0.1, with a thickness of 0.4 mm. Several samples of 3 cm × 3 cm are cut and polished with 400 mesh, 800 mesh, and 1200 mesh sandpaper in order. After polishing, they are placed in an ethanol solution for ultrasonic degreasing for 5 minutes and dried. Then a certain amount of 30 g / L NH4Cl+30 g / L (NH4)2CO3 mixed aqueous solution is sprayed on the sample, and it is placed in a 50°C oven. After ten minutes, the sample is taken out, sprayed with a certain amount of deionized water, and placed in the oven again. The above operation is repeated again after ten minutes. The above operation is repeated three times to obtain a rusted bronze sample. The surface rust layer is mainly composed of basic copper chloride Cu2(OH)3Cl.
[0019] Embodiment 1: A method for preparing a micron flower-like structure super-hydrophobic film on a rusty bronze surface comprises the following steps: S1. The raw material mass percentages of the pretreatment liquid are as follows: 0.1% trimesic acid, 0.06% sodium hydroxide, and the rest is solvent, with the volume fraction of ethanol in the solvent being 50%. After stirring and dissolving, the pH of the pretreatment liquid is adjusted to 7.0 using nitric acid. The raw material mass percentages of the membrane-forming liquid are as follows: 0.25% stearic acid, and the rest is ethanol. After stirring and dissolving, the pH is adjusted to 6.0 using sodium hydroxide or nitric acid. The pH of the obtained stearic acid ethanol solution is determined by the pH. If it is too high, it is neutralized with sodium hydroxide, and if it is low, a small amount of nitric acid is added.
[0020] In this embodiment, the preparation method of the pretreatment liquid is as follows: first prepare a solvent, the volume ratio of ethanol to water is 1:1, a portion of the water is used to prepare a 0.1 mol / L sodium hydroxide solution. The amount of the sodium hydroxide solution is calculated, the molar ratio of NaOH to trimesic acid is 3:1, then trimesic acid is added and stirred to dissolve, and finally 0.1 mol / L nitric acid is used to adjust the pH.
[0021] S2. Soak the prepared rusted bronze sample in the pretreatment solution for 12 h at a temperature of 25°C.
[0022] S3, take out the rusty bronze, rinse it with ethanol, and immerse it in the film-forming solution again for 1 h to prepare a super-hydrophobic film. The solution temperature during the immersion process is 25°C; S4. After the film is formed, take out the rusty bronze, rinse it with ethanol and blow it dry.
[0023] The following comparative examples were carried out according to the experimental parameters of Example 1.
[0024] Comparative Example 1: The rusted bronze sample was used as the experimental object, step S3 was removed, and other experimental parameters were the same as those in Example 1.
[0025] Comparative Example 2: The rusted bronze sample was used as the experimental object, step S2 was removed, and other experimental parameters were the same as those in Example 1.
[0026] Comparative Example 3: The rusted bronze sample was used as the experimental object, and the concentration of stearic acid in step S1 was modified to 0.1%. The other experimental parameters were the same as those in Example 1.
[0027] Comparative Example 4: The rusted bronze sample was used as the experimental object, the sodium hydroxide content in step S1 was modified to 0.02%, nitric acid was not added to adjust the pH, step S3 was removed, and other experimental parameters were the same as those in Example 1.
[0028] Comparative Example 5: The rusted bronze sample was used as the experimental object, the sodium hydroxide content in step S1 was modified to 0.04%, nitric acid was not added to adjust the pH, step S3 was removed, and other experimental parameters were the same as those in Example 1. The comprehensive performance test of the rusted bronze included: (1) Conducting contact angle test on bronze samples using a contact angle tester; (2) Observe the surface morphology of bronze samples by scanning electron microscopy; (3) The corrosion resistance of bronze samples was tested using a three-electrode system.
[0029] Figure 1 is the contact angle of a water drop on a rusty bronze surface that has been treated with a pretreatment solution and then with a film-forming solution. The contact angle of the superhydrophobic film obtained under this condition can reach 156.3°.
[0030] Figure 2 The following are SEM images of the rusted bronze surfaces obtained under different treatment conditions. Among them, (a) is the rusted bronze obtained in Comparative Example 2, (b) is the rusted bronze obtained in Comparative Example 1, (c) is the rusted bronze obtained in Example 1, (d) is the rusted bronze obtained in Comparative Example 4, and (e) is the rusted bronze obtained in Comparative Example 5.
[0031] Depend on Figure 2 As can be seen in (a), the rusty bronze surface after immersion in the film-forming liquid alone has many defects and no dense flower-like superhydrophobic structure is formed.
[0032] Depend on Figure 2 As can be seen in (b), the surface of the rusty bronze treated only with the pretreatment solution has more flower-like structures, which are complexes of copper and trimesic acid and do not have superhydrophobic properties. However, after the treatment, the surface of the rusty bronze is activated and can react better with stearic acid.
[0033] Depend on Figure 2 As can be seen in (c), after being treated with the pretreatment solution and then with the film-forming solution, the rusty bronze surface has a very dense micron flower-like structure that completely covers the rust layer surface.
[0034] Depend on Figure 2 As can be seen in (d) and (e), by adjusting the amount of sodium hydroxide and changing the pH of the pretreatment solution, the microscopic morphology of the rust layer surface after pretreatment can be regulated, and the microscopic morphology structure is almost non-hydrophobic.
[0035] Figure 3 The electrochemical impedance spectra of rusted bronze obtained under different treatment conditions are shown in Figure 1. (a) is the rusted bronze obtained in Comparative Example 2, (b) is the rusted bronze obtained in Comparative Example 1, (c) is the rusted bronze obtained in Example 1, and (d) is the rusted bronze obtained in Comparative Example 3.
[0036] Depend on Figure 3As can be seen in (a), the rusted bronze after being immersed in the film-forming liquid alone has a certain corrosion resistance, but due to its many defects, Warburg impedance appears, that is, the straight line sloping upward at the end of the curve.
[0037] Depend on Figure 3 As can be seen in (b), the rusted bronze treated only with the pretreatment solution has almost no corrosion resistance.
[0038] Depend on Figure 3 As can be seen in (c), the impedance arc radius of the rusted bronze treated with the pretreatment solution and then with the film-forming solution is one order of magnitude higher than that of the rusted bronze treated with the film-forming solution alone, indicating that it has better corrosion resistance.
[0039] Depend on Figure 3 As can be seen in (d), the impedance arc of the rusted bronze treated with the pretreatment solution and then with the film-forming solution with stearic acid concentration lower than the protection range is much lower than Figure 3 The impedance arc radius in (c) is only slightly better than that of the rusted bronze after being immersed in the film-forming liquid alone.
[0040] Therefore, the method of preparing a micron flower-like structure super-hydrophobic film on the surface of rusted bronze of the present invention can significantly enhance the hydrophobicity and corrosion resistance of the rusted bronze, thereby protecting the rusted bronze.
[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A method for preparing a super hydrophobic film on a rusty bronze surface, characterized in that: The following steps are involved: S1. Prepare a pretreatment solution and a film-forming solution: the pretreatment solution includes trimesic acid, sodium hydroxide, and nitric acid, and the solvent is a mixed solution of an organic solvent and water; the film-forming solution includes stearic acid, sodium hydroxide or nitric acid, and the solvent is an alcohol solvent; S2, soaking the rusted bronze in a pretreatment solution to activate the surface of the rust layer; S3, taking out the rusty bronze, washing it with an organic solvent and immersing it in a film-forming solution to prepare a super-hydrophobic film; S4. After the film is formed, take out the rusty bronze, rinse it with organic solvent and blow it dry.
2. The method for preparing a super-hydrophobic film on a rusty bronze surface according to claim 1, wherein In the solvent of the pretreatment liquid in step S1, the organic solvent is an alcohol solvent, preferably ethanol.
3. The method for preparing a super-hydrophobic film on a rusty bronze surface according to claim 1, wherein The solvent of the pretreatment liquid in step S1 is ethanol with a volume fraction of 40-55%.
4. The method for preparing a super-hydrophobic film on a rusty bronze surface according to claim 1, wherein The mass fractions of the substances in the pretreatment solution in step S1 are: trimesic acid 0.1-0.2%, sodium hydroxide 0.06-0.18%.
5. The method for preparing a super-hydrophobic film on a rusty bronze surface according to claim 1, wherein The mass fraction of each substance in the membrane-forming solution in step S1 is: stearic acid 0.2~0.3%.
6. The method for preparing a super hydrophobic film on a rusty bronze surface according to claim 1, wherein: In step S1, nitric acid is added to the pretreatment solution to adjust the pH to 6.0-8.
0.
7. The method for preparing a super hydrophobic film on a rusty bronze surface according to claim 1, wherein: The preparation method of the pretreatment liquid in step S1 is: first prepare a solvent, the volume ratio of ethanol to water is 1:1, a portion of the water is used to prepare a 0.1 mol / L sodium hydroxide solution, the amount of the sodium hydroxide solution is calculated, and the molar ratio of NaOH to trimesic acid is 3:1; then add trimesic acid and stir to dissolve, and finally use 0.1 mol / L nitric acid to adjust the pH.
8. The method for preparing a super hydrophobic film on a rusty bronze surface according to claim 1, wherein: In step S1, sodium hydroxide or nitric acid is added to the membrane-forming solution to adjust the pH to 5.0-6.
0.
9. The method for preparing a super hydrophobic film on a rusty bronze surface according to claim 1, wherein: The temperature of the solution during the soaking process of steps S2 and S3 is 20°C to 30°C.
10. Application of the method for preparing a super-hydrophobic film on a rusty bronze surface according to claim 1 in the anti-corrosion of bronze artifacts.