Corrosion-resistant waterproof coating and preparation method thereof

Abstract

The invention discloses a corrosion-resistant waterproof coating and a preparation method thereof, and relates to the technical field of protective coatings. The ceramic flexible fibers are embedded into tiny pores or uneven positions on the surface of the base material through impact force generated by a spraying process, and a three-dimensional network structure is formed on the surface, so that corrosion resistance and waterproofness of the coating are achieved, meanwhile, titanium sol and the metal base material are promoted to be combined and react through acting force, the metal surface is passivated, and the corrosion resistance of the coating is improved. The preparation method comprises the following steps: firstly, preparing a coating, further enhancing corrosion resistance and waterproofness, then forming a nanoscale rough surface on the coating through high-temperature treatment to realize hydrophobicity of a base material so as to gain the corrosion resistance and waterproof effects of the coating, and finally, spraying epoxy resin to form an ultrathin packaging coating, so that a rough hydrophobic structure is not influenced, and the corrosion resistance and waterproofness are further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of protective coatings, and particularly to a corrosion-resistant and waterproof coating and a preparation method thereof. Background Art

[0002] Regarding the concept of metal corrosion, it is generally considered that during the coexistence of metal materials and the external environment, physical and chemical reactions occur between them, and the phenomenon of gradual damage and deterioration occurs. Metal corrosion can be seen everywhere in our production and life. For example, the external rusting of steel products, the oxidation of steel exposed to the air for a long time, the appearance of a powdered aluminum oxide layer on utensils made of aluminum, etc. These phenomena are all metal corrosion. Due to the complex and diverse use environments of metal materials, environmental factors such as oxygen, temperature and humidity, and pH value can all cause the failure of metal material protection; the resulting adverse consequences include not only the effects on the appearance, color, and strength of the metal itself, but also the damage or scrapping of instruments, tools, and metal structures made of these metals, reducing their utilization efficiency, and even causing accidents and disasters in extreme cases. According to incomplete statistics, one-third of the world's annual steel production is scrapped due to corrosion. Excluding the recycled part, the waste of steel caused purely by corrosion reaches 10%.

[0003] The structural damage, energy efficiency decline, and economic losses caused by metal corrosion are incalculable. Therefore, the protection methods and effects of metal corrosion have attracted more and more attention. On the one hand, traditional metal corrosion protection measures may have certain negative impacts on the environment. For example, using toxic substances such as chromates for passivation treatment may cause environmental pollution; on the other hand, the protection effects of traditional protection measures have relatively large limitations, can only provide a certain degree of protection, and have high maintenance costs. For example, the coating may have problems such as peeling and cracking, resulting in the exposure of the metal to the corrosive environment. However, anti-corrosion coatings have been widely used in the field of metal protection due to their unique advantages such as low cost, fast construction, and strong corrosion resistance. The coating protection method refers to a class of liquid or solid materials that can form a thin film on the surface of an object under certain conditions to achieve protection, decoration, or other special functions (insulation, rust prevention, mildew prevention, heat resistance, etc.). It is a kind of coating widely used in modern industries, transportation, energy, ocean engineering and other departments. However, on the surface of some substrates that need to withstand deformation, such as the bending part of a metal pipe or the deformation area during the processing of a metal sheet, the flexibility of the coating is crucial. If the coating lacks flexibility, it is easy to crack when the substrate deforms, thereby destroying the protection performance of the coating and limiting the application of the coating. Summary of the Invention

[0004] The purpose of the present invention is to provide a corrosion-resistant and waterproof coating and a preparation method thereof to solve the problems existing in the prior art.

[0005] To solve the above technical problems, the present invention provides the following technical solutions: A preparation method of a corrosion-resistant and waterproof coating, comprising the following steps:

[0006] (1) Pretreat the ceramic flexible fibers, and then mix them with titanium sol to obtain a coating;

[0007] (2) Pretreat the iron plate, then spray the coating on its surface, and finally perform high-temperature treatment;

[0008] (3) Mix bisphenol A epoxy resin, accelerator, initiator, and dipropylene glycol diacrylate and spray them on the plate obtained in step (2) to obtain a packaging layer with a thickness of 5-30 μm, and then perform ultraviolet treatment to obtain a corrosion-resistant and waterproof coating;

[0009] The preparation method of the ceramic flexible fibers: Mix 10wt% polyvinylpyrrolidone-ethanol solution, 1mol / L nitric acid solution, and vinyltrimethylsiloxane, stir at 500 rpm for 4-8 h, perform ultrasonic treatment at 21 kHz for 10-30 min, add zirconium butoxide, aluminum butoxide, and acetic acid, stir for another 1 h, and perform spinning treatment. The needle diameter is 0.6 mm and the rate is 2000-4000 m / min. Finally, heat it to 600 °C at a rate of 1 °C / min in an argon atmosphere, keep it warm for 2 h, and then heat it to 900-1200 °C at a rate of 5 °C / min and keep it warm for 1 h to obtain; The mass ratio of the 10wt% polyvinylpyrrolidone-ethanol solution, 1mol / L nitric acid solution, vinyltrimethylsiloxane, zirconium butoxide, aluminum butoxide, and acetic acid is 5:1.5:1.5:3:3:4.

[0010] Further, the length of the ceramic flexible fibers in step (1) is 0.05-0.2 mm.

[0011] Further, the specific steps of the pretreatment in step (1) are: Adopt a low-temperature ammonia plasma process, and its process parameters are: temperature is 100-200 °C, air pressure is 80-100 MPa, power is 700-800 W, and time is 40-80 min.

[0012] Further, the mass ratio of the ceramic flexible fibers to titanium sol in step (1) is 1:50-100.

[0013] Further, the specific steps of the pretreatment in step (2) are: First, polish with 80-120 mesh sandpaper, then rinse with anhydrous ethanol 5 times, and finally treat with 10wt% sodium hydroxide solution under ultrasonic conditions at 21 kHz for 15 min and dry at 60 °C for 4 h.

[0014] Further, the spraying pressure in step (2) is 11-25 MPa, the running speed is 20-60 m / s, and the spraying angle is 30-80°.

[0015] Further, the temperature of the high-temperature treatment in step (2) is 400-700 °C and the time is 30-50 min.

[0016] Further, the ultraviolet treatment conditions in step (3) are: wavelength of 310-395 nm, intensity of 40-100 mW / cm 2 , temperature of 80 °C, and time of 5-30 s.

[0017] Further, the mass ratio of bisphenol A epoxy resin, accelerator, initiator, and dipropylene glycol diacrylate in step (3) is 50:0.2:0.2-0.6:5-15.

[0018] Compared with the prior art, the beneficial effects achieved are as follows:

[0019] In the present invention, the ceramic flexible fibers are first subjected to activation pretreatment so that the fiber surface is provided with polar groups such as amino groups, and then compounded with titanium sol. Through the impact force generated by the spraying process, the fiber material plays a mechanical anchoring role on the metal substrate. Some fibers can be embedded in the micro-pores or uneven places on the substrate surface and form a three-dimensional network structure on the surface, thereby preventing the penetration of corrosive media. Moreover, the amino groups on the fiber surface can form amide bonds with the active groups on the substrate surface, thereby enhancing the adhesion between the coating and the substrate, and thus realizing the corrosion resistance and waterproofness of the coating. At the same time, through the action force, the sol is promoted to combine and react with the free radicals on the surface of the metal substrate, thereby forming a stable complex and passivating the metal surface, further enhancing the corrosion resistance and waterproofness.

[0020] Secondly, through high-temperature treatment, nano-titanium dioxide is generated on the fiber surface and inside the coating. Then, by forming a nano-scale rough surface, the substrate realizes hydrophobicity, thereby greatly enhancing the corrosion resistance and waterproof effect of the coating. Finally, the epoxy resin monomer is sprayed and polymerized under ultraviolet and initiation conditions to form an ultra-thin encapsulation coating, so that the rough hydrophobic structure is not affected, thereby improving the corrosion resistance and waterproofness of the coating again. Specific Embodiments

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0022] In order to more clearly illustrate the method provided by the present invention, the following examples are used for detailed description. The test methods for each index of the corrosion-resistant and waterproof coating prepared in the following examples are as follows:

[0023] Waterproof property: Samples of the same size from the examples and comparative examples were taken for hydrophobic effect testing. The water contact angle of the fabric was measured using an OCA15EC type contact angle measuring instrument. The droplet volume was 8 μl, and the droplet rate was 2 μl / s.

[0024] Corrosion resistance: Samples of the same size from the examples and comparative examples were taken for acid and alkali resistance testing. The specimens were immersed in a 30 wt% sulfuric acid solution and a 10 wt% sodium hydroxide solution for 7 days respectively, and their changes were observed.

[0025] Example 1

[0026] (1) Mix a 10 wt% polyvinylpyrrolidone - ethanol solution, 1 mol / L nitric acid solution, and vinyltrimethylsiloxane, stir at 500 rpm for 4 h, ultrasonicate at 21 kHz for 10 min, add zirconium butoxide, aluminum butoxide, and acetic acid, then stir for 1 h, and perform spinning treatment with a needle diameter of 0.6 mm and a rate of 2000 m / min. Finally, heat it to 600 °C at a rate of 1 °C / min under an argon atmosphere, hold for 2 h, then heat it to 900 - 1200 °C at a rate of 5 °C / min and hold for 1 h to obtain ceramic flexible fibers; the mass ratio of the 10 wt% polyvinylpyrrolidone - ethanol solution, 1 mol / L nitric acid solution, vinyltrimethylsiloxane, zirconium butoxide, aluminum butoxide, and acetic acid is 5:1.5:1.5:3:3:4; Pretreat the ceramic flexible fibers: use a low - temperature ammonia plasma process with process parameters: temperature 100 °C, pressure 80 MPa, power 700 W, time 40 min, and then mix it evenly with titanium sol to obtain a coating; the mass ratio of the ceramic flexible fibers to the titanium sol is 1:50; the length of the ceramic flexible fibers is 0.05 mm; the model of the titanium sol is SS - TA10W;

[0027] (2) Pretreat the iron plate: First, polish it with 80 - mesh sandpaper, then rinse it 5 times with anhydrous ethanol, and finally treat it with a 10 wt% sodium hydroxide solution under 21 kHz ultrasonic conditions for 15 min, dry at 60 °C for 4 h, then spray the coating on its surface with a spraying pressure of 11 MPa, a running speed of 20 m / s, and a spraying angle of 30°, and finally perform high - temperature treatment at a temperature of 400 °C for 30 min;

[0028] (3) Mix bisphenol A epoxy resin, accelerator, initiator, and dipropylene glycol diacrylate and spray it on the plate obtained through step (2) to obtain a 5 - μm - thick encapsulation layer, and perform ultraviolet treatment with condition parameters: wavelength 310 nm, intensity 40 mW / cm 2, at a temperature of 80 °C and a time of 5 s, a corrosion-resistant and waterproof coating is obtained; the mass ratio of bisphenol A epoxy resin, promoter, initiator, and dipropylene glycol diacrylate is 50:0.2:0.2:5; the promoter is benzophenone; the initiator is OMNICAT 550.

[0029] Example 2

[0030] (1) Mix 10 wt% polyvinylpyrrolidone-ethanol solution, 1 mol / L nitric acid solution, and vinyltrimethylsiloxane, stir at 500 rpm for 6 h, sonicate at 21 kHz for 20 min, add zirconium butoxide, aluminum butoxide, and acetic acid, then stir for 1 h, and perform spinning treatment with a needle diameter of 0.6 mm and a rate of 3000 m / min. Finally, heat to 600 °C at 1 °C / min under an argon atmosphere, hold for 2 h, then heat to 1000 °C at 5 °C / min and hold for 1 h to obtain ceramic flexible fibers; the mass ratio of 10 wt% polyvinylpyrrolidone-ethanol solution, 1 mol / L nitric acid solution, vinyltrimethylsiloxane, zirconium butoxide, aluminum butoxide, and acetic acid is 5:1.5:1.5:3:3:4; pre-treat the ceramic flexible fibers: use a low-temperature ammonia plasma process with process parameters: temperature of 150 °C, pressure of 90 MPa, power of 750 W, and time of 60 min, and then mix evenly with titanium sol to obtain a coating; the mass ratio of the ceramic flexible fibers to the titanium sol is 1:80; the length of the ceramic flexible fibers is 0.12 mm; the model of the titanium sol is SS-TA10W;

[0031] (2) Pre-treat the iron plate: first sand it with 100-mesh sandpaper, then rinse it with anhydrous ethanol 5 times, and finally treat it with 10 wt% sodium hydroxide solution under 21 kHz ultrasonic conditions for 15 min, dry at 60 °C for 4 h, then spray the coating on its surface with a spraying pressure of 18 MPa, a running speed of 40 m / s, and a spraying angle of 50°, and finally perform high-temperature treatment at a temperature of 550 °C and a time of 40 min;

[0032] (3) Mix bisphenol A epoxy resin, promoter, initiator, and dipropylene glycol diacrylate and spray them on the plate obtained in step (2) to obtain a packaging layer with a thickness of 17 μm, and perform ultraviolet treatment with the following condition parameters: wavelength of 365 nm, intensity of 70 mW / cm 2 , at a temperature of 80 °C and a time of 18 s, a corrosion-resistant and waterproof coating is obtained; the mass ratio of bisphenol A epoxy resin, promoter, initiator, and dipropylene glycol diacrylate is 50:0.2:0.4:10; the promoter is benzophenone; the initiator is OMNICAT 550.

[0033] Example 3

[0034] (1) Mix a 10 wt% polyvinylpyrrolidone - ethanol solution, 1 mol / L nitric acid solution, and vinyltrimethylsiloxane, stir at 500 rpm for 8 h, sonicate at 21 kHz for 10 - 30 min, add zirconium n - butoxide, aluminum n - butoxide, and acetic acid, then stir for 1 h, and perform spinning treatment with a needle diameter of 0.6 mm and a rate of 4000 m / min. Finally, heat to 600 °C at a rate of 1 °C / min under an argon atmosphere, hold for 2 h, then heat to 1200 °C at a rate of 5 °C / min and hold for 1 h to obtain ceramic flexible fibers; the mass ratio of the 10 wt% polyvinylpyrrolidone - ethanol solution, 1 mol / L nitric acid solution, vinyltrimethylsiloxane, zirconium n - butoxide, aluminum n - butoxide, and acetic acid is 5:1.5:1.5:3:3:4; Pretreat the ceramic flexible fibers: use a low - temperature ammonia plasma process with process parameters: temperature of 200 °C, pressure of 100 MPa, power of 800 W, and time of 80 min, then mix evenly with titanium sol to obtain a coating; the mass ratio of the ceramic flexible fibers to the titanium sol is 1:50 - 100; the length of the ceramic flexible fibers is 0.2 mm; the model of the titanium sol is SS - TA10W;

[0035] (2) Pretreat the iron plate: first polish it with 120 - mesh sandpaper, then rinse it 5 times with anhydrous ethanol, and finally treat it with a 10 wt% sodium hydroxide solution under 21 kHz ultrasonic conditions for 15 min, dry at 60 °C for 4 h, then spray the coating on its surface with a spraying pressure of 25 MPa, a running speed of 60 m / s, and a spraying angle of 80°, and finally perform high - temperature treatment at a temperature of 700 °C for 50 min;

[0036] (3) Mix bisphenol A epoxy resin, accelerator, initiator, and dipropylene glycol diacrylate and spray them on the plate obtained through step (2) to obtain a 30 - μm - thick encapsulation layer, and perform ultraviolet treatment with the following condition parameters: wavelength of 395 nm, intensity of 100 mW / cm 2 , temperature of 80 °C, and time of 30 s to obtain a corrosion - resistant and waterproof coating; the mass ratio of bisphenol A epoxy resin, accelerator, initiator, and dipropylene glycol diacrylate is 50:0.2:0.6:15; the accelerator is benzophenone; the initiator is OMNICAT 550.

[0037] Comparative Example 1

[0038] The difference between Comparative Example 1 and Example 2 lies in that step (1) is different. Step (1) is changed to: Mix 10 wt% polyvinylpyrrolidone-ethanol solution, 1 mol / L nitric acid solution, and vinyltrimethylsiloxane, stir at 500 rpm for 6 h, ultrasonicate at 21 kHz for 20 min, add zirconium butoxide, aluminum butoxide, and acetic acid, then stir for 1 h, and conduct spinning treatment with a needle diameter of 0.6 mm and a rate of 3000 m / min. Finally, heat to 600 °C at 1 °C / min under an argon atmosphere, hold for 2 h, then heat to 1000 °C at 5 °C / min, and hold for 1 h to obtain ceramic flexible fibers; the mass ratio of the 10 wt% polyvinylpyrrolidone-ethanol solution, 1 mol / L nitric acid solution, vinyltrimethylsiloxane, zirconium butoxide, aluminum butoxide, and acetic acid is 5:1.5:1.5:3:3:4; Pretreat the ceramic flexible fibers: Use a low-temperature ammonia plasma process with process parameters: temperature of 150 °C, pressure of 90 MPa, power of 750 W, and time of 60 min, and then mix evenly with ethanol to obtain a coating; the mass ratio of the ceramic flexible fibers to ethanol is 1:80; the length of the ceramic flexible fibers is 0.12 mm; the remaining steps are the same as those in Example 2.

[0039] Comparative Example 2

[0040] The difference between Comparative Example 2 and Example 2 is that step (1) is absent. Step (2) is changed to: Pretreat the iron plate: First, polish it with 100-mesh sandpaper, then rinse it with anhydrous ethanol 5 times, and finally treat it with 10 wt% sodium hydroxide solution under 21 kHz ultrasonic conditions for 15 min, dry at 60 °C for 4 h, and then spray titanium sol on its surface with a spraying pressure of 18 MPa, a running speed of 40 m / s, and a spraying angle of 50°. Finally, conduct high-temperature treatment with a temperature of 550 °C and a time of 40 min; the model of the titanium sol is SS-TA10W; the remaining steps are the same as those in Example 2.

[0041] Comparative Example 3

[0042] The difference between Comparative Example 3 and Example 2 is that step (3) is absent; the remaining steps are the same as those in Example 2.

[0043] Effect Example

[0044] The following Table 1 gives the performance analysis results of the corrosion-resistant and waterproof coatings using Examples 1 to 3 and Comparative Examples 1 to 3 of the present invention.

[0045] Table 1

[0046]

[0047] From the comparison of the experimental results between the examples and the comparative examples in Table 1, it can be found that in the present invention, the ceramic flexible fibers are first subjected to activation pretreatment to make the fiber surface carry polar groups such as amino groups, and then compounded with titanium sol. Through the impact force generated by the spraying process, the fiber material plays a mechanical anchoring role on the metal substrate. Some fibers can be embedded in the tiny pores or uneven places on the substrate surface and form a three-dimensional network structure on the surface, thereby preventing the penetration of corrosive media. Moreover, the amino groups on the fiber surface can generate amide bonds with the active groups on the substrate surface, thereby enhancing the adhesion between the coating and the substrate, so as to achieve the corrosion resistance and waterproofness of the coating. At the same time, through the action force, the sol is promoted to combine and react with the free radicals on the surface of the metal substrate, and then a stable complex is formed to passivate the metal surface, further enhancing the corrosion resistance and waterproofness. Then, through high-temperature treatment, nano-titanium dioxide is generated on the fiber surface and inside the coating. Furthermore, by forming a nano-scale rough surface, the substrate is made hydrophobic, thus greatly enhancing the corrosion resistance and waterproof effect of the coating. Finally, the epoxy resin monomer is sprayed and polymerized under ultraviolet and initiation conditions to form an ultra-thin encapsulation coating, so that the rough hydrophobic structure is not affected, thereby improving the corrosion resistance and waterproofness of the coating again.

[0048] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be regarded as limiting the claimed claim.

Claims

1. A method for preparing a corrosion-resistant and waterproof coating, characterized in that, It includes the following steps: (1) Pretreat the ceramic flexible fibers, and then mix them evenly with titanium sol to obtain a coating; (2) Pretreat the iron plate, then spray the coating on its surface, and finally conduct high-temperature treatment; (3) Mix bisphenol A epoxy resin, accelerator, initiator, and dipropylene glycol diacrylate and spray them on the plate obtained through step (2) to obtain a packaging layer with a thickness of 5 - 30 μm, and then obtain a corrosion-resistant and waterproof coating through ultraviolet treatment; The preparation method of the ceramic flexible fibers: Mix 10wt% polyvinylpyrrolidone - ethanol solution, 1mol / L nitric acid solution, and vinyltrimethylsiloxane, stir at 500 rpm for 4 - 8 h, ultrasonicate at 21 kHz for 10 - 30 min, add zirconium butoxide, aluminum butoxide, and acetic acid, stir for another 1 h, and conduct spinning treatment with a needle diameter of 0.6 mm and a rate of 2000 - 4000 m / min. Finally, heat it to 600 °C at a rate of 1 °C / min under an argon atmosphere, hold for 2 h, then heat it to 900 - 1200 °C at a rate of 5 °C / min, and hold for 1 h to obtain; the mass ratio of the 10wt% polyvinylpyrrolidone - ethanol solution, 1mol / L nitric acid solution, vinyltrimethylsiloxane, zirconium butoxide, aluminum butoxide, and acetic acid is 5:1.5:1.5:3:3:

4.

2. The preparation method of a corrosion-resistant and waterproof coating according to claim 1, characterized in that, The length of the ceramic flexible fibers in step (1) is 0.05 - 0.2 mm.

3. The preparation method of a corrosion-resistant and waterproof coating according to claim 1, characterized in that The specific steps of the pretreatment in step (1) are: adopt a low-temperature ammonia plasma process with process parameters: temperature of 100 - 200 °C, pressure of 80 - 100 MPa, power of 700 - 800 W, and time of 40 - 80 min.

4. The preparation method of a corrosion-resistant and waterproof coating according to claim 1, characterized in that, The mass ratio of the ceramic flexible fibers to titanium sol in step (1) is 1:50 - 100.

5. The preparation method of a corrosion-resistant and waterproof coating according to claim 1, characterized in that, The specific steps of the pretreatment in step (2) are: first polish with 80 - 120 mesh sandpaper, then rinse with absolute ethanol 5 times, and finally treat with 10wt% sodium hydroxide solution under 21 kHz ultrasonic conditions for 15 min and dry at 60 °C for 4 h.

6. The preparation method of a corrosion-resistant and waterproof coating according to claim 1, characterized in that The spraying pressure in step (2) is 11 - 25 MPa, the running speed is 20 - 60 m / s, and the spraying angle is 30 - 80°.

7. The preparation method of a corrosion-resistant and waterproof coating according to claim 1, characterized in that The temperature of the high-temperature treatment in step (2) is 400 - 700 °C and the time is 30 - 50 min.

8. The preparation method of a corrosion-resistant and waterproof coating according to claim 1, characterized in that, The UV treatment conditions described in step (3): wavelength is 310 - 395 nm, intensity is 40 - 100 mW / cm 2 , temperature is 80 °C, and time is 5 - 30 s.

9. The preparation method of a corrosion-resistant and waterproof coating according to claim 1, characterized in that, The mass ratio of bisphenol A epoxy resin, accelerator, initiator, and dipropylene glycol diacrylate in step (3) is 50:0.2:0.2 - 0.6:5 - 15.

Images