An organic-inorganic hybrid waterborne coating resistant to 700 °C high temperature and its preparation method

Abstract

The present invention relates to the technical field of the preparation of high-temperature waterborne coatings, and particularly relates to an organic-inorganic hybrid waterborne coating capable of withstanding a high temperature of 700 °C and a preparation method thereof. By adopting an organic-inorganic hybrid technology to provide a crosslinked skeleton for the coating, and using SiO<subgt;2< / subgt>@PANI core-shell particles obtained by coating nanosilica with polyaniline as nano-silicon powder, silica can be more stably present in the crosslinked skeleton of the organic-inorganic hybrid, while improving the processing performance and barrier performance of PANI, enhancing the adhesion of PANI to the metal substrate. Moreover, the polyaniline on the outer shell of the Si02@PANI core-shell particles is hydrophobic, while the waterborne aluminum powder is hydrophilic, which enables them to be better compatible. The waterborne aluminum powder can isolate most of the light and heat from the external environment, and as a filler, it can better improve the high-temperature resistance of the inorganic-organic silicon hybrid resin. The waterborne aluminum powder also provides high-temperature isolation protection for the Si02@PANI core-shell particles, further enhancing the durability of the coating.

Description

Technical Field

[0001] The present invention relates to the technical field of the preparation of high-temperature waterborne coatings, and particularly relates to an organic-inorganic hybrid waterborne coating capable of withstanding a high temperature of 700 °C and a preparation method thereof. Background Art

[0002] Most of the existing high-temperature resistant paints have the problems of single functionality and poor durability. If they exist on the surface of high-temperature metals for a long time, it will cause a decrease in the adhesion of the paint film, and then cracking, discoloration and rusting will occur. Nowadays, the types of high-temperature mechanical equipment are emerging in an endless stream, and the temperature on the surface of their metals is usually suitable for the range of 200-700 °C. The long-term high-temperature environment will damage the internal structure of the traditional paint film, reduce its adhesion, cause cracking and falling of the metal paint film, and rusting of the surface of the equipment. This undoubtedly poses a huge potential safety hazard to the high-temperature working environment. Moreover, the metal surface in a long-term high-temperature state also has very high requirements for the high-temperature oxidation and discoloration resistance of the topcoat. The rusted and discolored paint film will also affect the overall aesthetics of the public.

[0003] In the current research on high-temperature resistant paints, for example, in a Chinese patent with the application number CN202210615954.8, an organic-inorganic hybrid waterborne coating and a preparation method thereof are disclosed. Through the organic-inorganic hybrid method, nano-SiO2 silica sol is modified by a silane coupling agent, combining the characteristics of an organic coating and an inorganic coating to form a unique coating with good heat resistance, excellent weather resistance and corrosion resistance. However, the use of a large amount of silane coupling agent, although improving the interfacial bonding force between the organic and inorganic components, also destroys the chemical stability and thermal stability inside the coating. When the coating is sprayed onto the metal surface, under high temperature, light and heat will quickly penetrate through the coating to reach the metal surface, resulting in the peeling of the formed paint film.

[0004] For another example, in a Chinese patent with the application number CN202211647485.4, an organic-inorganic hybrid polymer hydrogel, its preparation method, and an exterior wall thermal insulation intermediate paint are disclosed. The formulation of the exterior wall thermal insulation intermediate paint no longer solely uses inorganic silica aerogel and organic film-forming substances. Instead, the two are hybridized into an organic-inorganic hybrid dispersion, which is then added to the paint, improving the dispersion effect and production efficiency, and avoiding problems that may occur when mixing silica aerogel and polymer emulsion / resin in paint production, such as paint caking, too high viscosity, and post-thickening. Moreover, hollow glass microspheres modified with a silane coupling agent are used as low-thermal-conductivity heat insulation fillers, enhancing the compatibility and binding force with the film-forming system, and improving the adhesion of the paint film to the substrate, water resistance, and flexibility. However, at 700°C, the modified hollow glass microspheres cannot stably exist in the organic-inorganic hybrid crosslinked framework, still unable to isolate light and heat conduction to the metal surface, and the problem of paint film peeling still occurs.

[0005] Therefore, to solve the above problems, it is very necessary to develop a multifunctional waterborne topcoat paint that can withstand high temperatures, prevent discoloration, and has strong adhesion. Summary of the Invention

[0006] Aiming at the problem that existing topcoat paints cannot withstand 700°C high temperature, the purpose of the present invention is to provide an organic-inorganic hybrid waterborne paint that can withstand 700°C high temperature and its preparation method. By adopting the organic-inorganic hybrid technology to provide a crosslinked framework for the coating, and using SiO2@PANI core-shell particles obtained by coating nano-silica with polyaniline as nano-silicon powder, silica can exist more stably in the organic-inorganic hybrid crosslinked framework. While improving the processing performance and barrier performance of PANI, it also improves the adhesion of PANI to the metal substrate. Moreover, the polyaniline on the outer shell of the SiO2@PANI core-shell particles is hydrophobic, and the waterborne aluminum powder is hydrophilic, which enables them to be better compatible. The waterborne aluminum powder can isolate most of the light and heat from the external environment, and as a filler, it can better improve the high-temperature resistance characteristics of the inorganic-organic silicon hybrid resin. Using the waterborne aluminum powder also provides high-temperature isolation protection for the SiO2@PANI core-shell particles, further enhancing the durability of the coating.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] An organic-inorganic hybrid waterborne paint that can withstand 700°C high temperature, calculated by mass ratio, includes the following components:

[0009] 5-6% deionized water, 4-6% organic hybrid resin, 2-5% nano silicon powder, 5-10% talcum powder, 5-7% film-forming aid, 2-4% additive, 4-6% nano-precipitated barium sulfate, 5-10% water-based aluminum powder, and the rest is water-based inorganic hybrid resin. The water-based inorganic hybrid resin contains fumed silica and nano-silica particles. The particle size of fumed silica is 0.1-1μm, and the diameter of nano-silica particles is 20-50nm.

[0010] As an improvement, the film-forming aid is composed of alcohol ester twelve and dipropylene glycol methyl ether in a mass ratio of 1:3.

[0011] As an improvement, the additive is composed of a dispersant, an antifoaming agent, a leveling agent, an amine neutralizer, a thickener, and a flash rust inhibitor in a mass ratio of 1:5:1:1:1:7.

[0012] As an improvement, the particle size of the water-based aluminum powder is 20-50nm, and the particle size of the nano-precipitated barium sulfate is 0.1μm.

[0013] As an improvement, the nano silicon powder, nano-precipitated barium sulfate, talcum powder, and water-based aluminum powder are composed in a mass ratio of 1:1:1:2.

[0014] As an improvement, the nano silicon powder is composed of SiO2@PANI core-shell particles obtained by coating nano-silica with polyaniline, and the diameter is 25μm.

[0015] As an improvement, the synthesis method of the nano silicon powder is as follows:

[0016] Silica particles are dispersed in distilled water under ultrasound, then aniline is added, and the pH is stabilized at 3.5 by adding hydrochloric acid to form a suspension. The resulting suspension is stirred until homogeneous at room temperature, and then an aqueous solution of APS oxidant is dropped into the suspension to form a dark green reaction mixture. The pH value is stabilized at 1.5 and stirred until the polymerization process ends. The particles are recovered by centrifugation, and the recovered particles are washed four times with ethanol and deionized water and dried at 80°C for 16 hours to obtain nano silicon powder.

[0017] In addition, the present invention provides a method for preparing the above-mentioned organic-inorganic hybrid water-based coating that can withstand high temperatures of 700°C, including the following steps:

[0018] S1. Using deionized water as the base, at a rotation speed of 400-1000 rpm, the additive and talcum powder are added in sequence and continuously stirred for 8-15 minutes to obtain mixture A;

[0019] S2. Add the grinding medium to mixture A in step S1 and grind it in a shaker or sand mill to obtain a ground product with a fineness ≤ 30μm;

[0020] S3. Under stirring at a rotation speed of 400 - 1000 rpm, successively add silicone resin, nano silicon powder, additives, nano precipitated barium sulfate and film-forming aids to the ground material in step S2, and continue stirring for 8 - 15 min to obtain mixture B;

[0021] S4. Stir at a rotation speed of 9000 - 1500 rpm, add aqueous aluminum powder and continue stirring for 8 - 15 min until it is uniformly stirred without granularity to obtain component A of the organic-inorganic hybrid waterborne coating;

[0022] S5. Stir at a rotation speed of 9000 - 1500 rpm, add the aqueous hybrid inorganic resin as component B to the mixture in step S4, and continue stirring for 8 - 15 min until it is uniformly stirred to obtain the organic-inorganic hybrid waterborne coating.

[0023] As an improvement, in step S1, the stirring rotation speed is 500 - 800 rpm, and the continuous stirring time is 10 min;

[0024] In step S2, the grinding medium is glass beads with a diameter of 0.2 mm, the content of the grinding medium accounts for 70% of the mass ratio of mixture A, the grinding time is 20 min, and the fineness of the ground material ≤ 30 μm;

[0025] In step S3, the stirring rotation speed is 500 - 800 rpm, and the continuous stirring time is 10 min;

[0026] In step S4, the stirring rotation speed is 1000 - 1200 rpm, and the continuous stirring time is 10 min;

[0027] In step S5, the stirring rotation speed is 1000 - 1200 rpm, and the continuous stirring time is 10 min.

[0028] Furthermore, the present invention also provides an application scenario of the organic-inorganic hybrid waterborne coating capable of withstanding high temperature of 700 °C. Cover the surface of the object to be constructed with the coating, with a thickness of 20 - 30 microns, and dry for 24 hours. After baking the paint film surface at 700 °C for 24 hours, there is no obvious change in the paint film surface, the cross-cut adhesion is 0 - 2 levels, and the pencil hardness of the coating ≥ HB.

[0029] The beneficial effects of the present invention are as follows:

[0030] (1) The present invention adopts an organic-inorganic hybrid technology to provide a crosslinked framework for the coating, enabling it to have the effect of high temperature resistance and no color change at high temperatures. Among them, the inorganic hybrid resin and the silicone resin complement each other. The inorganic hybrid resin provides a rigid high-temperature-resistant framework structure on the basis of the silicone resin, and the presence of the silicone resin provides toughness and adhesiveness for the rigid framework. The inorganic silica sol component is mainly composed of clusters of nano-silica. These clusters can fill fine voids and have a coupling effect with inorganic materials and resins, making the coating have better rigidity and denseness. Its existence can maintain the excellent protection of the original hybrid resin and the high stability of the silicone-based coating, and can overcome the problem that the paint is prone to deformation during storage at room temperature;

[0031] (2) Under the action of the waterborne aluminum powder in the present invention, external gases and moisture cannot reach the substrate through the capillary pores, providing good physical shielding for the topcoat. Moreover, the aluminum powder can isolate most of the light and heat in the external environment, and as a filler, it can better enhance the high-temperature resistance characteristics of the inorganic-organic silicone hybrid resin;

[0032] (3) The core-shell structure of SiO2@PANI adopted in the present invention can enable silica to exist more stably in the organic-inorganic hybrid crosslinked framework. While improving the processing performance and barrier performance of PANI, it improves the adhesion of PANI to the metal substrate, further enhancing the durability of the coating. Moreover, the polyaniline presenting as the shell of the SiO2@PANI core-shell particles is hydrophobic, and the waterborne aluminum powder is hydrophilic. This property enables them to be better compatible, so that the SiO2@PANI core-shell particles can be protected from high temperatures by the waterborne aluminum powder, isolating the influence of external high temperatures, light and heat on it;

[0033] (4) A small amount of aluminum powder in the present invention will react with polyaniline, thus effectively improving the wear resistance of polyaniline. Nano-precipitated barium sulfate, as a extender pigment, increases the coating thickness and workability. In addition, due to the surface effect of the nano-particles, it further enhances the hardness and mechanical properties of the coating. At the same time, the extender pigment will absorb the deformation stress generated when the coating is heated, making the coating have better high-temperature resistance and thermal shock performance.

[0034] In summary, the present invention is applied to the high-temperature metal surface of mechanical equipment by spraying or smearing to form a waterborne hybrid high-temperature-resistant coating with high temperature resistance, long-term color retention and strong adhesion, and is particularly suitable for the topcoat technology field of mechanical surface protection coatings in high-temperature environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic flow chart of the preparation method of the organic-inorganic hybrid waterborne coating of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in 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 creative efforts shall fall within the protection scope of the present invention.

[0037] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0038] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0039] Example:

[0040] An organic-inorganic hybrid waterborne coating resistant to 700 °C high temperature, by mass ratio, includes the following components:

[0041] Deionized water 5 - 6%, organic hybrid resin 4 - 6%, nano-silica powder 2 - 5%, talcum powder 5 - 10%, film-forming aid 5 - 7%, additive 2 - 4%, nano-precipitated barium sulfate 4 - 6%, waterborne aluminum powder 5 - 10%, and the rest is waterborne inorganic hybrid resin. The waterborne inorganic hybrid resin contains fumed silica and nano-silica particles. The particle size of fumed silica is 0.1 - 1 μm, and the diameter of nano-silica particles is 20 - 50 nm.

[0042] As an improvement, the film-forming aid is composed of dodecyl alcohol ester and dipropylene glycol methyl ether according to a mass ratio of 1:3.

[0043] As an improvement, the additive is composed of a dispersant, an antifoaming agent, a leveling agent, an amine neutralizer, a thickener, and a flash rust inhibitor according to a mass ratio of 1:5:1:1:1:7.

[0044] As an improvement, the particle size of the waterborne aluminum powder is 20 - 50 nm, and the particle size of the nano-precipitated barium sulfate is 0.1 μm.

[0045] As an improvement, the nano-silica powder, nano-precipitated barium sulfate, talc powder, and water-based aluminum powder are composed according to a mass ratio of 1:1:1:2.

[0046] As an improvement, the nano-silica powder is composed of SiO2@PANI core-shell particles obtained by coating nano-silica with polyaniline, and the diameter is 25 μm.

[0047] As an improvement, the synthesis method of the nano-silica powder is as follows:

[0048] The silica particles are dispersed in distilled water under ultrasonic conditions, then aniline is added, and the pH is stabilized at 3.5 by adding hydrochloric acid to form a suspension. The resulting suspension is stirred until homogeneous at room temperature, and then an aqueous solution of APS oxidant is dropped into the suspension to form a dark green reaction mixture. The pH value is stabilized at 1.5 and stirred until the polymerization process ends. The particles are recovered by centrifugation, and the recovered particles are washed four times with ethanol and deionized water and dried at 80 °C for 16 hours to obtain the nano-silica powder.

[0049] As Figure 1 shown, in addition, the present invention provides a method for preparing the above-mentioned organic-inorganic hybrid water-based coating that can withstand a high temperature of 700 °C, including the following steps:

[0050] S1. Using deionized water as the base, at a rotation speed of 400 - 1000 rpm, additives and talc powder are sequentially added and continuously stirred for 8 - 15 min to obtain mixture A;

[0051] S2. Add the grinding medium to mixture A in step S1 and grind it in a shaker or sand mill to obtain a ground product with a fineness ≤ 30 μm;

[0052] S3. Under stirring at a rotation speed of 400 - 1000 rpm, silicone resin, nano-silica powder, water-based inorganic hybrid resin, additives, nano-precipitated barium sulfate, and film-forming aids are sequentially added to the ground product in step S2, and continue to stir for 8 - 15 min to obtain mixture B;

[0053] S4. Stir at a rotation speed of 9000 - 1500 rpm, add water-based aluminum powder and continuously stir for 8 - 15 min until it is stirred evenly without particles to obtain component A of the organic-inorganic hybrid water-based coating;

[0054] S5. Stir at a rotation speed of 9000 - 1500 rpm, add the water-based hybrid inorganic resin as component B to the mixture in step S4, and continuously stir for 8 - 15 min until it is stirred evenly to obtain the organic-inorganic hybrid water-based coating.

[0055] As an improvement, in step S1, the stirring speed is 500 - 800 rpm, and the continuous stirring time is 10 min;

[0056] In step S2, the grinding medium is glass beads with a diameter of 0.2 mm, the content of the grinding medium accounts for 70% of the mass ratio of the mixture A, the grinding time is 20 min, and the fineness of the ground material is ≤ 30 μm;

[0057] In step S3, the stirring speed is 500 - 800 rpm, and the continuous stirring time is 10 min;

[0058] In step S4, the stirring speed is 1000 - 1200 rpm, and the continuous stirring time is 10 min;

[0059] In step S5, the stirring speed is 9000 - 1500 rpm, and the continuous stirring time is 10 min.

[0060] Furthermore, the present invention also provides an application scenario of the organic - inorganic hybrid water - borne coating resistant to 700 °C high temperature. The coating is covered on the surface of the object to be constructed, with a thickness of 20 - 30 microns, and dried for 24 hours. After baking the paint film surface at 700 °C for 24 hours, there is no obvious change in the paint film surface, the cross - cut adhesion is 0 - 2 levels, and the pencil hardness of the coating is ≥ HB.

[0061] Examples 1 - 4:

[0062] The following is the content table of each component of the organic - inorganic hybrid water - borne coating resistant to 700 °C high temperature in Examples 1 - 4, as shown in Table 1.

[0063] Table 1

[0064]

[0065] Comparative Examples 1 - 3:

[0066] The following is the content table of each component of the water - borne coating in Comparative Examples 1 - 3, as shown in Table 2.

[0067] Table 2

[0068]

[0069] In Comparative Examples 1-3 and Examples 1-4, the film-forming aid is composed of alcohol ester dodecanol and dipropylene glycol methyl ether in a mass ratio of 1:3. In the examples, the film-forming aid comprises a dispersant, defoamer, leveling agent, amine neutralizer, thickener, and flash rust inhibitor in a mass ratio of 1:5:1:1:1:7. In Example 4, the solid component preferably comprises nano-silicon powder (particle size 25 μm), nano-precipitated barium sulfate (particle size 0.1 μm), talc, and water-based aluminum powder (particle size 20-50 nm) in a mass ratio of 1:1:1:2. Excessive amounts of talc and nano-precipitated barium sulfate can result in excessive viscosity, making dispersion of the nano-silicon powder difficult, while excessive rigidity can easily lead to cracking of the paint surface. The appropriate addition of water-based aluminum powder can effectively improve the paint's high-temperature resistance. Excessive or insufficient amounts can result in excessive thickness or failure to meet high-temperature resistance standards. This ratio achieves the perfect ratio of powder to solvent and resin, resulting in a smooth, complete paint surface with excellent overall performance.

[0070] The organic-inorganic hybrid waterborne coatings of Examples 1-4 and Comparative Examples 1-3 were prepared using the preparation methods described in the Examples. The 700°C high-temperature-resistant organic-inorganic hybrid waterborne coatings obtained in Examples 1-4 and Comparative Examples 1-3 were subjected to cross-hatch adhesion testing, impact resistance testing, salt spray resistance testing, and high-temperature resistance testing in accordance with the standards GB / T 9286, GB / T 1732, GB / T 1771, and GB / T 1735, respectively. The test results are shown in Table 3 below:

[0071] Table 3. Performance test comparison between comparative example and example

[0072]

[0073] As shown in Table 3, Example 4 exhibits the best overall performance. Comparative Examples 1 and 3 exhibit far less than ideal adhesion, impact resistance, salt spray resistance, and heat resistance. Comparative Example 2 exhibits comparable salt spray resistance and heat resistance to Example 4, with adhesion and salt spray resistance only slightly inferior to those of Example 4. The curing of silicone resins typically relies on the silanol condensation reaction to produce silanol-oxygen chains. The continued condensation reaction gradually reduces the silanol concentration, increases steric hindrance, and reduces fluidity, leading to a decrease in reaction rate.

[0074] Combined with the above content and Table 3, it can be seen that the ratio of silicone resin to inorganic resin plays a decisive role in the adhesion, impact resistance, salt spray resistance and heat resistance of the topcoat, which means whether the siloxane group and the inorganic cross-linked skeleton can be completely compounded. On this basis, the addition of waterborne aluminum powder further improves the high-temperature resistance of the topcoat. The core-shell structure of Si02@PANI provides more stable silica for the topcoat, and better improves the impact resistance of the paint surface. In addition, they can fill fine voids and couple with inorganic materials and resins, making the coating have better rigidity, denseness and durability. Their existence can maintain the excellent protection of the original hybrid resin and the high stability of the silicon-based coating, and can overcome the problem that the paint is prone to deformation during storage at room temperature. The reaction between polyaniline and waterborne aluminum powder also effectively improves the wear resistance of the coating.

[0075] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An organic-inorganic hybrid waterborne coating resistant to 700 °C high temperature, characterized in that, By mass ratio, it includes the following components: Deionized water 5 - 6%, silicone resin 4 - 6%, nano silicon powder 2 - 5%, talcum powder 5 - 10%, film-forming aid 5 - 7%, additive 2 - 4%, nano-precipitated barium sulfate 4 - 6%, water-based aluminum powder 5 - 10%, and the rest is water-based inorganic hybrid resin. The additive is composed of a dispersant, an antifoaming agent, a leveling agent, an amine neutralizer, a thickener, and a flash rust inhibitor according to a mass ratio of 1:5:1:1:1:

7. The water-based inorganic hybrid resin contains fumed silica and nano-silica particles. The particle size of the fumed silica is 0.1 - 1 μm, and the diameter of the nano-silica particles is 20 - 50 nm; The particle size of the water-based aluminum powder is 20 - 50 nm, and the particle size of the nano-precipitated barium sulfate is 0.1 μm; The nano silicon powder, nano-precipitated barium sulfate, talcum powder, and water-based aluminum powder are composed according to a mass ratio of 1:1:1:2; The composition of the nano silicon powder is SiO2@PANI core-shell particles obtained by coating nano-silica with polyaniline, with a diameter of 25 μm; The synthesis method of the nano silicon powder is as follows: Silica particles are dispersed in distilled water under ultrasonic waves, then aniline is added, and the pH is stabilized at 3.5 by adding hydrochloric acid to form a suspension. The resulting suspension is stirred until homogeneous at room temperature, and then an aqueous solution of APS oxidant is dropped into the suspension to form a dark green reaction mixture. The pH value is stabilized at 1.5 and stirred until the polymerization process ends. The particles are recovered by centrifugation, and the recovered particles are washed four times with ethanol and deionized water and dried at 80°C for 16 hours to obtain nano silicon powder; The coating is covered on the surface of the object to be constructed to form a paint film with a thickness of 20 - 30 microns and dried for 24 hours. After baking the paint film at 700°C for 24 hours, there is no obvious change on the paint film surface, the cross-cut adhesion is 0 - 2 levels, and the pencil hardness of the coating is ≥ HB.

2. A kind of organic-inorganic hybrid water-based coating that can withstand high temperature of 700°C according to claim 1, characterized in that: The film-forming aid is composed of dodecyl alcohol ester and dipropylene glycol methyl ether according to a mass ratio of 1:

3.

3. A method for preparing the organic-inorganic hybrid waterborne coating capable of withstanding high temperature of 700 °C as described in any one of claims 1-2, characterized in that, It includes the following steps: S1. Using deionized water as the base, at a rotation speed of 400 - 1000 rpm, the additive and talcum powder are successively added and continuously stirred for 8 - 15 min to obtain mixture A; S2. Add the grinding medium to mixture A in step S1 and put it into a shaker or a sand mill for grinding to obtain a grinding material with a fineness ≤ 30 μm; S3. Under stirring at a rotation speed of 400 - 1000 rpm, the silicone resin, nano silicon powder, water-based inorganic hybrid resin, additive, nano-precipitated barium sulfate, and film-forming aid are successively added to the grinding material in step S2 and continue to stir for 8 - 15 min to obtain mixture B; S4. Stir at a rotation speed of 9000 - 1500 rpm, add water-based aluminum powder and continuously stir for 8 - 15 min until it is stirred evenly without particles to obtain the organic-inorganic hybrid water-based coating.

4. The method according to claim 3, characterized in that: In step S1, the stirring rotation speed is 500 - 800 rpm, and the continuous stirring time is 10 min; In step S2, the grinding medium is glass beads with a diameter of 0.2 mm, the content of the grinding medium accounts for 70% of the mass ratio of the mixture A, the grinding time is 30 min, and the fineness of the ground material is ≤ 20 μm; In step S3, the stirring speed is 500 - 800 rpm, and the continuous stirring time is 10 min; In step S4, the stirring speed is 1000 - 1200 rpm, and the continuous stirring time is 10 min.

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