High-temperature-resistant anticorrosive paint as well as preparation and use methods thereof

Abstract

The invention discloses a high-temperature-resistant anticorrosive coating as well as a preparation method and a use method thereof. The high-temperature-resistant anticorrosive coating is prepared from the following components in parts by mass: 13 to 30 parts of organic silicon resin, 1 to 3 parts of fumed silica, 12 to 26 parts of quartz powder, 2 to 5 parts of mica powder, 1 to 5 parts of titanium dioxide, 0.1 to 3 parts of silicon carbide, 5 to 20 parts of low-melting-point glass powder, 30 to 60 parts of solvent, 0.1 to 0.5 part of dispersing agent and 0.1 to 0.3 part of flatting agent. The organic silicon resin is used as bonding resin, and the fumed silica, the quartz powder, the mica powder, the titanium dioxide, the silicon carbide and the low-melting-point glass powder are used as fillers, so that the obtained coating has the characteristics of high temperature resistance and good shielding effect on hydrogen sulfide gas corrosion.

Description

Technical Field

[0001] The present invention relates to the technical field of coating materials, and in particular to a high temperature resistant anticorrosive coating and a preparation and use method thereof. Background Art

[0002] High temperature resistant coatings mainly include organic polymer-based high temperature resistant coatings and ceramic-based high temperature resistant coatings. Organic polymer-based high temperature resistant coatings mainly use organic polymer resins as film-forming materials, which will decompose in large quantities at a high temperature of 600°C, resulting in powdering, cracking, and shedding of the coating. Therefore, the current organic polymer-based high temperature resistant coatings are not very heat resistant, generally not exceeding 600°C. Ceramic-based high temperature resistant coatings are difficult to construct, with a coating thickness of more than 1mm. They are easily affected by thermal expansion and contraction on metal substrates, resulting in cracking and shedding. Once damaged, they are difficult to repair and can only be completely removed.

[0003] Since heat-resistant stainless steel is a high-nickel alloy, it is easily corroded by hydrogen sulfide gas. When the metal temperature approaches or exceeds 630°C, the corrosion product (a mixture of nickel and nickel sulfide) will melt into liquid and the corrosion rate will increase dramatically.

[0004] Therefore, it is of great significance to provide a coating material that is resistant to high temperatures and can isolate hydrogen sulfide gas corrosion. Summary of the invention

[0005] In view of the above-mentioned deficiencies, the object of the present invention is to provide a high temperature resistant anti-corrosion coating and a preparation and use method thereof, so as to solve the problem that the high temperature resistance of the existing coating does not exceed 600°C and the shielding effect against hydrogen sulfide gas is poor.

[0006] To achieve the above object, the present invention is implemented through the following technical solutions: In a first aspect, the present invention provides a high temperature resistant anti-corrosion coating, which comprises, by mass: 13-30 parts of silicone resin, 1-3 parts of fumed silica, 12-26 parts of quartz powder, 2-5 parts of mica powder, 1-5 parts of titanium dioxide, 0.1-3 parts of silicon carbide, 5-20 parts of low melting point glass powder, 30-60 parts of solvent, 0.1-0.5 parts of dispersant, and 0.1-0.3 parts of leveling agent.

[0007] Preferably, the silicone resin includes one or more of polyalkyl silicone resin, polyaryl silicone resin and polyalkylaryl silicone resin.

[0008] Preferably, the solvent is one or more of ethylene glycol butyl ether, butyl acetate, and propylene glycol methyl ether acetate.

[0009] Preferably, the dispersant is one or more of BYK-110, BASF4401, and BYK161; and the leveling agent is one or more of BYK-306, BYK354, and BYK399.

[0010] In a second aspect, the present invention provides a method for preparing a high temperature resistant anti-corrosion coating, comprising the following steps: mixing silicone resin, fumed silica, quartz powder, mica powder, titanium dioxide, silicon carbide, low melting point glass powder, solvent, dispersant and leveling agent, and dispersing them evenly to obtain a high temperature resistant anti-corrosion coating.

[0011] In a third aspect, the present invention provides a method for using a high temperature resistant anti-corrosion coating, comprising the following steps: coating the high temperature resistant anti-corrosion coating described in the first aspect on a substrate, drying it at a first temperature, then heating it to a second temperature and keeping it warm, and after cooling, obtaining a high temperature resistant anti-corrosion coating.

[0012] Preferably, the first temperature is 80-90°C, and the second temperature is 1000-1100°C.

[0013] Preferably, the drying time is 20 to 30 minutes; the insulation time is 20 to 30 minutes.

[0014] Preferably, the coating method is spraying or brushing; the thickness of the high temperature resistant anti-corrosion coating is 30-40 μm.

[0015] Preferably, the substrate is made of stainless steel.

[0016] The beneficial effects of the present invention are: 1. The present invention uses silicone resin as a bonding resin, and fumed silica, quartz powder, mica powder, titanium dioxide, silicon carbide, and low-melting-point glass powder as fillers. The resulting coating has the characteristics of being resistant to high temperatures and having a good shielding effect against hydrogen sulfide gas corrosion.

[0017] 2. When the coating provided by the present invention is used, it is dried at a first temperature and then heated to a second temperature and kept warm. During the drying stage at the first temperature, the silicone resin is used as a binder to form a film once. During the process of heating to the second temperature, the silicone resin is gradually decomposed. After the silicon and oxygen elements are converted into silicon dioxide, they are well compatible with the melted low-melting-point glass powder, thereby replacing the silicone resin as a binder to form a secondary film with other fillers in the coating to form a smooth and dense inorganic coating. The resulting coating solves the problem of corrosion of the base material by hydrogen sulfide gas under long-term conditions of 1000°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings of the embodiment are briefly introduced below.

[0019] Figure 1This is a picture of the coating of Example 1 after endurance at 1000°C for 500 hours in a hydrogen sulfide atmosphere; Figure 2 This is a picture of the coating of Example 2 after endurance at 1000°C for 500 hours in a hydrogen sulfide atmosphere; Figure 3 This is a picture of the coating of Example 3 after endurance at 1000°C for 500 hours in a hydrogen sulfide atmosphere; Figure 4 This is a picture of the coating of comparative example 1 after endurance at 1000°C for 96 hours in a hydrogen sulfide atmosphere; Figure 5 This is a picture of the coating of comparative example 2 after endurance at 1000°C for 96 hours in a hydrogen sulfide atmosphere; Figure 6 This is a cross-sectional view of a fully enclosed sample of the coating of Example 2 after the coating has been subjected to 1050° C. resistance in a hydrogen sulfide atmosphere for 500 hours; Figure 7 These are the front and back pictures of the single-sided coating sample of Example 2 after the coating was resistant to 1050°C in a hydrogen sulfide atmosphere for 72 hours. DETAILED DESCRIPTION

[0020] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] An embodiment of the present invention provides a high temperature resistant anti-corrosion coating, which includes, by mass: 13-30 parts of silicone resin, 1-3 parts of fumed silica, 12-26 parts of quartz powder, 2-5 parts of mica powder, 1-5 parts of titanium dioxide, 0.1-3 parts of silicon carbide, 5-20 parts of low-melting point glass powder, 30-60 parts of solvent, 0.1-0.5 parts of dispersant, and 0.1-0.3 parts of leveling agent.

[0022] The silicone resin includes one or more of polyalkyl silicone resin, polyaryl silicone resin, and polyalkylaryl silicone resin; the solvent includes but is not limited to one or more of ethylene glycol butyl ether, butyl acetate, and propylene glycol methyl ether acetate; the dispersant is one or more of BYK-110, BASF4401, and BYK161; and the leveling agent is one or more of BYK-306, BYK354, and BYK399.

[0023] The embodiment of the present invention also provides a method for using a high temperature resistant anticorrosion coating, comprising the following steps: applying the high temperature resistant anticorrosion coating of the above formula on a substrate by spraying or brushing, drying at 80-90°C for 20-30 minutes, then heating to 1000-1100°C and keeping the temperature for 20-30 minutes, and cooling to obtain a high temperature resistant anticorrosion coating. The thickness of the high temperature resistant anticorrosion coating can be 30-40 μm, and the substrate can be a stainless steel material.

[0024] It should be noted that the low-melting-point glass powder in the present invention refers to glass powder with a melting point of 600°C-900°C.

[0025] Example 1 1. Coating preparation 21 parts of polymethyl silicone resin, 2 parts of fumed silica, 15 parts of quartz powder, 3 parts of mica powder, 5 parts of titanium dioxide, 0.5 parts of silicon carbide, 13 parts of low-melting point glass powder, 45 parts of ethylene glycol butyl ether, 0.3 parts of dispersant (BYK-110) and 0.2 parts of leveling agent (BYK-306) were dispersed on a high-speed disperser at 3000 rpm for 15 minutes to obtain a high-temperature resistant anti-corrosion coating.

[0026] 2. Paint coating process The high temperature resistant anti-corrosion coating prepared in this example was applied to the S310 stainless steel plate by air spraying, the coating thickness was controlled to be about 35 μm, and dried at 80° C. for 30 minutes. Then the temperature was gradually raised to 1000° C. and maintained for 30 minutes, and then cooled to room temperature to obtain the high temperature resistant anti-corrosion coating.

[0027] Example 2 1. Coating preparation 18 parts of polyethyl silicone resin, 1 part of fumed silica, 16 parts of quartz powder, 2 parts of mica powder, 2 parts of titanium dioxide, 0.2 parts of silicon carbide, 7 parts of low-melting point glass powder, 54 parts of ethylene glycol butyl ether, 0.2 parts of dispersant (BYK-110) and 0.2 parts of leveling agent (BYK-306) were dispersed on a high-speed disperser at 3000 rpm for 15 minutes to obtain a high-temperature resistant anti-corrosion coating.

[0028] 2. Paint coating process The high temperature resistant anti-corrosion coating prepared in this example was applied to the S310 stainless steel plate by air spraying, the coating thickness was controlled to be about 35 μm, and dried at 80° C. for 30 minutes. Then the temperature was gradually raised to 1100° C. and maintained for 20 minutes, and then cooled to room temperature to obtain the high temperature resistant anti-corrosion coating.

[0029] Example 3 1. Coating preparation 26 parts of polyaryl silicone resin, 2.5 parts of fumed silica, 15 parts of quartz powder, 3 parts of mica powder, 1 part of titanium dioxide, 3 parts of silicon carbide, 11 parts of low-melting point glass powder, 39 parts of ethylene glycol butyl ether, 0.4 parts of dispersant (BYK-110) and 0.3 parts of leveling agent (BYK-306) were dispersed on a high-speed disperser at 3000 rpm for 15 minutes to obtain a high-temperature resistant anti-corrosion coating.

[0030] 2. Paint coating process The high temperature resistant anti-corrosion coating prepared in this example was applied to the S310 stainless steel plate by brushing, the coating thickness was controlled to be about 35 μm, and dried at 80° C. for 30 min. Then the temperature was gradually raised to 1050° C. and maintained for 25 min, and then cooled to room temperature to obtain the high temperature resistant anti-corrosion coating.

[0031] Comparative Example 1 An organosilicon coating was prepared according to the method of Example 1 in Publication No. CN106280987A, and applied on a S310 stainless steel plate by air spraying, and dried at 80° C. for 30 minutes to obtain an organosilicon coating.

[0032] Comparative Example 2 The commercially available Akzo Nobel brand Intertherm 751CSA high temperature resistant anti-corrosion coating was used and applied on the S310 stainless steel plate by air spraying according to the requirements of its product manual to obtain a high temperature resistant anti-corrosion coating.

[0033] The coatings prepared in Examples 1 to 3 and Comparative Examples 1 and 2 were tested for performance, and the results are shown in Table 1.

[0034] Table 1

[0035] As can be seen from Table 1, the coating prepared by using the coating provided by the present invention has the characteristics of resistance to high temperature of 1000°C, high hardness, adhesion level 0, and good shielding effect against hydrogen sulfide gas corrosion; while the coatings of Comparative Example 1 and Comparative Example 2 show powdering and cracking phenomena at 1000°C. Under long-term conditions of 1000°C, the corrosion of hydrogen sulfide gas to stainless steel materials is aggravated, and the corrosion is serious.

[0036] Figures 1 to 3 These are pictures of the coatings of Examples 1 to 3 after endurance at 1000°C for 500 hours in a hydrogen sulfide atmosphere. Figures 4 and 5 These are pictures of the coatings of Comparative Examples 1 and 2 resisting 1000°C in a hydrogen sulfide atmosphere for 96 hours. It can be seen that the coating provided by the present invention can prevent the corrosion of the base material by hydrogen sulfide gas under long-term high temperature conditions.

[0037] In the laboratory tube furnace test, hydrogen sulfide gas was introduced at 1050℃, and the coating was fully enclosed. After 500 hours of testing, there was no corrosion on the surface, the adhesion was still level 0, and the thickness of the sample did not change. Figure 6 As shown, the sample was cut open to observe the corrosion of the cross section. The interior of the stainless steel was still the original color of the metal, and there was only a gray corrosion layer of about 0.1 mm at the contact with the coating. The single-sided closed sample was tested under the same conditions for 72 hours. Figure 7 As shown, there is no corrosion on the coated surface ( Figure 7 a), the adhesion score is still level 0, the uncoated surface is severely corroded, and the sample thickness is reduced by 2mm ( Figure 7 b). Experiments show that the coating can effectively delay the corrosion of stainless steel by hydrogen sulfide gas at 1000°C, significantly improving the service life of stainless steel in high temperature environments.

[0038] It should be noted that the above embodiments all belong to the same inventive concept, and the description of each embodiment has its own focus. For matters that are not described in detail in some embodiments, reference may be made to the description in other embodiments.

[0039] The above-mentioned embodiments only express the implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A high temperature resistant anticorrosive coating, characterized in that: Calculated by mass, it includes: 13-30 parts of silicone resin, 1-3 parts of fumed silica, 12-26 parts of quartz powder, 2-5 parts of mica powder, 1-5 parts of titanium dioxide, 0.1-3 parts of silicon carbide, 5-20 parts of low-melting point glass powder, 30-60 parts of solvent, 0.1-0.5 parts of dispersant, and 0.1-0.3 parts of leveling agent.

2. The high temperature resistant anticorrosion coating according to claim 1, characterized in that: The organic silicone resin includes one or more of polyalkyl organic silicone resin, polyaryl organic silicone resin and polyalkylaryl organic silicone resin.

3. The high temperature resistant anticorrosion coating according to claim 1, characterized in that: The solvent is one or more of ethylene glycol butyl ether, butyl acetate, and propylene glycol methyl ether acetate.

4. The high temperature resistant anticorrosion coating according to claim 1, characterized in that: The dispersant is one or more of BYK-110, BASF4401, and BYK161; the leveling agent is one or more of BYK-306, BYK354, and BYK399.

5. The method for preparing the high temperature resistant anticorrosive coating according to any one of claims 1 to 4, characterized in that: The following steps are involved: Organic silicon resin, fumed silica, quartz powder, mica powder, titanium dioxide, silicon carbide, low-melting-point glass powder, solvent, dispersant and leveling agent are mixed and dispersed evenly to obtain the high-temperature resistant anticorrosive coating.

6. A method for using a high temperature resistant anticorrosive coating, characterized in that: The method comprises the following steps: coating the high temperature resistant anti-corrosion coating according to any one of claims 1 to 4 on a substrate, drying the coating at a first temperature, heating the substrate to a second temperature and keeping the temperature constant, and cooling the substrate to obtain a high temperature resistant anti-corrosion coating.

7. The method for using the high temperature resistant anticorrosive coating according to claim 6, characterized in that: The first temperature is 80-90°C, and the second temperature is 1000-1100°C.

8. The method for using the high temperature resistant anticorrosive coating according to claim 6, characterized in that: The drying time is 20 to 30 minutes; the heat preservation time is 20 to 30 minutes.

9. The method for using the high temperature resistant anticorrosive coating according to claim 6, characterized in that: The coating method is spraying or brushing; the thickness of the high temperature resistant anti-corrosion coating is 30-40 μm.

10. The method for using the high temperature resistant anticorrosive coating according to claim 6, characterized in that: The substrate is made of stainless steel.

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