A low-temperature curing organosilicon high-temperature resistant coating and its preparation method and application

Abstract

The present invention relates to an organosilicon high-temperature resistant coating, and in particular to an organosilicon high-temperature resistant coating that cures at low temperatures, and a preparation method and application thereof. The organosilicon high-temperature resistant coating of the present invention is composed of component A and component B; component A includes an organosilicon resin and an organic modified silicone resin; component B includes a curing agent and an adhesion promoter. The resin system adopted by the present invention has a silicon-oxygen bond (-Si-O-) main chain content that is significantly higher than that of a chemically modified organosilicon resin, and the heat resistance will not be significantly reduced; the curing agent selected by the present invention can react with the organosilicon resin and the modified organosilicon resin at low temperatures or even at room temperature. Therefore, the high-temperature resistant coating prepared by the present invention reduces the curing temperature while also having heat resistance; it solves the contradiction between the low-temperature curing and poor thermal stability of organosilicon coatings.

Description

Technical Field

[0001] The present invention relates to an organic silicon high temperature resistant coating, and more particularly to an organic silicon high temperature resistant coating that cures at low temperatures, and a preparation method and application thereof. Background Art

[0002] In industrial applications such as high-temperature chimneys and pipelines, various materials are frequently used under high-temperature conditions. These materials are susceptible to oxidation at high temperatures, causing performance degradation or even failure. Protective coating technology is the simplest and most effective way to protect materials under these conditions, leading to the development of high-temperature resistant coatings.

[0003] For high temperatures below 700°C, organic high-temperature resistant coatings have great advantages over inorganic high-temperature resistant coatings, such as convenient construction and low curing temperature. Among organic high-temperature resistant coatings, silicone coatings have been widely studied due to their excellent high-temperature resistance. Jun Zhao et al. (The High-Temperature Resistance Properties of Polysiloxane / AlCoatings with Low Infrared Emissivity. Coatings, 2018, 8(4).) used silicone resin as a film-forming resin and added pigments and fillers such as flaky aluminum powder to make a high-temperature resistant coating. After curing at 200°C, the coating can withstand high temperatures of 600°C. Zhang Yuzhong et al. (Preparation of High-Temperature-Resistant Silicone Insulating Coatings for Aircraft [J]. Shanghai Coatings, 2014, 52(08): 14-17) compared and analyzed the heat resistance of five silicone resins from China and abroad and selected Dow Corning silicone resin, which has better heat resistance, as the film-forming material. The coating was cured at 200°C for 2 hours, with an impact resistance of 50 cm and a flexibility of 2 mm. After being subjected to 700°C for 5 hours, the coating did not bubble or peel. However, the fatal disadvantage of silicone coatings is their high curing temperature, generally greater than 200°C. In practical applications, it is difficult to achieve high-temperature curing conditions, especially for large-sized or large-volume components, which seriously restricts the use of silicone coatings in high-temperature protection applications.

[0004] To address the technical shortcomings of high-temperature curing of silicone heat-resistant coatings, existing technologies modify organic resins to produce modified silicone resins; for example, epoxy-modified silicone resins, acrylic-modified silicone resins, polyester-modified silicone resins, and polyurethane-modified silicone resins. Although the curing temperature of some modified silicone resins is reduced, their heat resistance is significantly reduced. Coatings prepared with these resins can withstand short-term high temperatures, but prolonged exposure to high temperatures can lead to noticeable discoloration, cracking, and even shedding. This seriously impacts the use of silicone heat-resistant coatings in certain applications. In other words, while modified silicone resins can lower the curing temperature, they sacrifice high-temperature resistance. This demonstrates the persistent conflict between the curing temperature and thermal stability of silicone resin coatings. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the present invention provides a high-temperature resistant silicone coating that can be cured at low temperature or even at room temperature.

[0006] The present invention adopts silicone resin and modified silicone resin in a specific ratio as the film-forming material of the high-temperature resistant coating, and by selecting components that can react with the silicone resin and the modified silicone resin respectively as curing agents, the coating can be cured at low temperature and has excellent heat resistance.

[0007] One of the purposes of the present invention is to provide a low temperature curing organosilicon high temperature resistant coating.

[0008] The low-temperature curing organosilicon high-temperature resistant coating is composed of independent components A and B; the weight ratio of component A to component B is 100:1-10, preferably 100:2-6, more preferably 100:3-5, for example 100:4;

[0009] The component A comprises a resin; the resin is composed of an organic silicone resin and a modified organic silicone resin, and the weight ratio of the organic silicone resin to the modified organic silicone resin is 100:5-15, preferably 100:8-11;

[0010] The B component includes a curing agent and an adhesion promoter; the weight ratio of the curing agent to the adhesion promoter is 100:40-90, preferably 100:60-70.

[0011] In the present invention, the silicone resin accounts for a relatively large proportion in the coating resin system, which can account for more than 90% in preferred examples; at the same time, the modified group in the modified silicone resin accounts for a relatively low proportion, which greatly maintains the heat resistance of the silicone. Therefore, the resin system used in the present invention has a significantly higher main chain content of silicon-oxygen bonds (-Si-O-) than the chemically modified silicone resin, and the heat resistance will not be significantly reduced. The above-mentioned curing agent selected in the present invention can react with the silicone resin and the modified silicone resin at low temperatures or even at room temperature. In summary, the high-temperature resistant coating prepared by the present invention reduces the curing temperature while also having heat resistance.

[0012] Experimental studies have found that if the weight ratio of silicone resin to modified silicone resin is too high, the resulting coating may not fully cure or even fail to crosslink at low temperatures, exhibiting low pencil hardness, easy scratching, and poor water resistance, salt spray resistance, and resistance to heat and humidity. If the weight ratio of silicone resin to modified silicone resin is too low, the resulting coating's heat resistance decreases, with noticeable discoloration at 350°C and even cracking and shedding after prolonged exposure to 350°C. Therefore, the present invention limits the weight ratio of silicone resin to modified silicone resin to 100:5-15.

[0013] The modified silicone resin refers to a novel resin formed by modifying a silicone resin with an organic resin. Specifically, the modified silicone resin can be selected from at least one of epoxy-modified silicone resin, acrylic-modified silicone resin, polyester-modified silicone resin, and polyurethane-modified silicone resin. All of these modified silicone resins can be commercially available.

[0014] The curing agent can be selected from at least one of γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, and γ-mercaptopropyltrimethoxysilane, preferably at least one of γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-mercaptopropyltriethoxysilane. The above curing agents can all be obtained commercially.

[0015] In some embodiments of the present invention, the curing agent used is γ-aminopropyltriethoxysilane, γ-mercaptopropyltriethoxysilane, or γ-glycidyloxypropyltrimethoxysilane. For example, when the modified silicone resin is an epoxy-modified silicone resin, γ-aminopropyltriethoxysilane can be selected as the curing agent; when the modified silicone resin is a polyurethane-modified silicone resin, γ-mercaptopropyltriethoxysilane can be selected as the curing agent; when the modified silicone resin is a polyester-modified silicone resin or an acrylic-modified silicone resin, γ-glycidyloxypropyltrimethoxysilane can be selected as the curing agent.

[0016] The adhesion promoter can be any one of the existing adhesion promoters that can be used in the art, and specifically, can be selected from one or both of BYK-4512 and BYK-C8001.

[0017] Component A of the low-temperature curing organosilicon heat-resistant coating may also contain conventional additives and pigments and fillers in the art. For example, Component A may include one or more of mica powder, titanium dioxide, copper chrome black, talc, leveling agent, defoamer, anti-settling agent, wetting and dispersing agent, and solvent. Specific examples are as follows:

[0018] The component A may further include mica powder; based on 100 parts by weight of the resin, the mica powder comprises 40-80 parts by weight, preferably 40-60 parts by weight.

[0019] The component A may further include titanium dioxide; based on 100 parts by weight of the resin, the amount of titanium dioxide is 30-60 parts by weight, preferably 30-50 parts by weight.

[0020] The component A further comprises copper chrome black; based on 100 parts by weight of the resin, the copper chrome black comprises 5-20 parts by weight, preferably 8-12 parts by weight.

[0021] The A component may further include the following components; each component is calculated based on 100 parts by weight of the resin:

[0022] 30-50 parts by weight of talc;

[0023] 3-6 parts by weight of leveling agent;

[0024] 1.5-4 parts by weight of defoaming agent;

[0025] 1.5-4 parts by weight of anti-settling agent;

[0026] 2.5-5 parts by weight of wetting and dispersing agent;

[0027] 30-60 parts by weight of solvent.

[0028] The mica powder, titanium dioxide, and copper chrome black can all be any existing mica powder, titanium dioxide, and copper chrome black that are used in the art. Specifically, the titanium dioxide can be selected from one or more of DuPont R706, Chuntai R960, and Zhonghe Titanium Dioxide R-2219; the mica powder can be selected from one or both of Huayuan wet-process muscovite 1250 mesh and Jinya wet-process muscovite 1250 mesh; and the copper chrome black can be selected from one or more of Nori NL-04, Jufa JFA-2852, and Zhengnian K3000.

[0029] The mica powder is a layered silicate that provides oxygen barrier protection in the present invention. The titanium dioxide and copper chrome black are high-temperature resistant pigments that provide color matching. The simultaneous addition of the titanium dioxide, mica powder, and copper chrome black may produce a synergistic effect, forming a filler network and potentially creating a "closely packed" state, providing excellent oxygen barrier protection for the resin.

[0030] The talc, leveling agent, defoamer, anti-settling agent, and wetting and dispersing agent are commonly used adjuvants in this field; any existing talc, leveling agent, defoamer, anti-settling agent, and wetting and dispersing agent that can be used in this field can be used; all of them can be obtained through commercial channels. For example, the talc can be selected from one or both of Xin Ge talc and Wei Bo talc; the leveling agent can be selected from one or more of TEGO-410, BYK-314, and AFCONA A-3236; the defoamer can be selected from one or more of BYK-077, TEGO-Airex900, and AFCONA-A2020; the anti-settling agent can be selected from one or both of AFCONA A-0571 and Japan Kusumoto 420-20; and the wetting and dispersing agent can be selected from one or both of BYK-ANTI-TERRA-204 and Disponer 903.

[0031] The solvent may be selected from at least one of xylene, n-butanol, butyl acetate and propylene glycol methyl ether acetate.

[0032] According to some embodiments disclosed herein, the organosilicon high temperature resistant coating is composed of independent component A and component B; the weight ratio of component A to component B is 100:1-10, preferably 100:2-6, and more preferably 100:3-5;

[0033] The A component includes:

[0034] 100 parts by weight of resin;

[0035] 40-80 parts by weight, preferably 40-60 parts by weight, of mica powder;

[0036] 30-60 parts by weight, preferably 30-50 parts by weight, of titanium dioxide;

[0037] Copper chrome black 5-20 parts by weight, preferably 8-12 parts by weight;

[0038] 30-50 parts by weight of talc;

[0039] 3-6 parts by weight of leveling agent;

[0040] 1.5-4 parts by weight of defoaming agent;

[0041] 1.5-4 parts by weight of anti-settling agent;

[0042] 2.5-5 parts by weight of wetting and dispersing agent;

[0043] 30-60 parts by weight of solvent;

[0044] The B component includes a curing agent and an adhesion promoter; the weight ratio of the curing agent to the adhesion promoter is 100:40-90, preferably 100:60-70;

[0045] The resin is composed of an organic silicone resin and a modified organic silicone resin, and the weight ratio of the organic silicone resin to the modified organic silicone resin is 100:5-15, preferably 100:8-11;

[0046] The modified silicone resin is epoxy-modified silicone resin, polyurethane-modified silicone resin, polyester-modified silicone resin or acrylic-modified silicone resin;

[0047] The curing agent is γ-aminopropyltriethoxysilane, γ-mercaptopropyltriethoxysilane or γ-glycidyloxypropyltrimethoxysilane.

[0048] A second object of the present invention is to provide a method for preparing the organosilicon high-temperature resistant coating described in one of the objects of the invention.

[0049] The preparation method includes: mixing and grinding the components of component A according to the weight ratio or weight parts to obtain component A, mixing the components of component B according to the weight parts to obtain component B, and mixing components A and B according to the weight ratio to obtain the organic silicon high-temperature resistant coating.

[0050] The method for using the organic silicon high temperature resistant coating comprises rolling, brushing or spraying the organic silicon high temperature resistant coating on the surface of a substrate.

[0051] The third object of the present invention is to provide an application of the organosilicon high-temperature resistant coating described in one of the inventions in the fields of high-temperature chimneys, high-temperature pipelines, automobiles, and aircraft.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] 1. The low-temperature curing organosilicon heat-resistant coating prepared by the present invention overcomes the disadvantage of heat-resistant coatings generally requiring high-temperature curing. It can be cured at low temperatures (less than 80°C) or even at room temperature. This not only reduces the energy consumption during high-temperature curing of the coating, but also greatly increases the ease of application of the heat-resistant coating.

[0054] 2. Compared with single modified silicone resin coatings, the coating prepared by the present invention has better heat resistance and can be used for a long time at a high temperature of 350°C without changing color.

[0055] 3. The coating prepared by the present invention has a good coating pot life of up to 6 hours after the coating is prepared and can be applied by conventional air spraying.

[0056] 4. The coating prepared by the present invention has good liquid medium resistance, corrosion resistance and environmental adaptability.

[0057] 5. The disclosed method and process for preparing the low-temperature curable organosilicon heat-resistant coating is simple, effectively reducing production costs. This method and process involves physical mixing of different materials, without chemical synthesis or modification. Compared to chemically modified organosilicon heat-resistant coatings, this method and process is simpler and easier to operate, making it highly practical.

[0058] In the present invention, the "low temperature" refers to 80°C or less. DETAILED DESCRIPTION

[0059] The present invention will be described in detail below with reference to specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and are not to be construed as limiting the scope of protection of the present invention. Non-essential improvements and adjustments made by those skilled in the art to the present invention based on the contents of the present invention still fall within the scope of protection of the present invention.

[0060] The reagents used in the following examples and comparative examples are all commercially available products.

[0061] Example 1

[0062] (1) 95 parts by weight of silicone resin, 5 parts by weight of epoxy-modified silicone resin, 60 parts by weight of titanium dioxide R706, 12 parts by weight of copper chrome black 2852, 40 parts by weight of Huayuan wet-process muscovite 1250 mesh, 2 parts by weight of AFCONAA-0571 anti-settling agent, 30 parts by weight of pigeon talc, 6 parts by weight of BYK-314 leveling agent, 4 parts by weight of BYK-077 defoaming agent, 5 parts by weight of BYK-ANTI-TERRA-204 wetting and dispersing agent, 26.5 parts by weight of xylene and 3.5 parts by weight of n-butanol were added to a container in sequence, stirred for 0.5 h, ground and dispersed with a sand mill until the fineness was ≤40 μm, filtered, and sealed and packaged to obtain component A;

[0063] (2) In a container, 100 parts by weight of γ-aminopropyltriethoxysilane and 70 parts by weight of BYK-4512 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0064] (3) The component A and component B prepared above were mixed in a weight ratio of A:B=100:1 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0065] Example 2

[0066] (1) 92.5 parts by weight of silicone resin, 7.5 parts by weight of epoxy-modified silicone resin, 50 parts by weight of titanium dioxide R706, 10 parts by weight of copper chrome black 2852, 60 parts by weight of Huayuan wet-process muscovite 1250 mesh, 4 parts by weight of AFCONA A-0571 anti-settling agent, 50 parts by weight of pigeon talc, 3 parts by weight of BYK-314 leveling agent, 1.5 parts by weight of BYK-077 defoaming agent, 2.5 parts by weight of BYK-ANTI-TERRA-204 wetting and dispersing agent, 52.5 parts by weight of xylene and 7.5 parts by weight of n-butanol were added to a container in sequence, stirred for 0.5 h, ground and dispersed with a sand mill until the fineness was ≤40 μm, filtered, and sealed and packaged to obtain component A;

[0067] (2) In a container, 100 parts by weight of γ-aminopropyltriethoxysilane and 60 parts by weight of BYK-4512 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0068] (3) The component A and component B prepared above were mixed in a weight ratio of A:B=100:3 to prepare a coating material, which was applied to the surface of a substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0069] Example 3

[0070] (1) 91.3 parts by weight of silicone resin, 8.7 parts by weight of epoxy modified silicone resin, 40 parts by weight of titanium dioxide R706, 8 parts by weight of copper chrome black 2852, 50 parts by weight of Huayuan wet-process muscovite 1250 mesh, 3 parts by weight of AFCONA A-0571 anti-settling agent, 40 parts by weight of pigeon talc powder, 4 parts by weight of BYK-314 leveling agent, 2.3 parts by weight of BYK-077 defoaming agent, 3.2 parts by weight of

[0071] BYK-ANTI-TERRA-204 wetting and dispersing agent, 35 parts by weight of xylene and 5 parts by weight of n-butanol were stirred for 0.5 h, and ground and dispersed with a sand mill until the fineness was ≤ 40 μm. The material was filtered and sealed to obtain component A.

[0072] (2) In a container, 100 parts by weight of γ-aminopropyltriethoxysilane and 60 parts by weight of BYK-4512 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0073] (3) The component A and component B prepared above were mixed in a weight ratio of A:B=100:5 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0074] Example 4

[0075] (1) Add 90 parts by weight of silicone resin, 10 parts by weight of epoxy modified silicone resin, 30 parts by weight of titanium dioxide R706, 6 parts by weight of copper chrome black 2852, 80 parts by weight of Huayuan wet-process muscovite 1250 mesh, 1.5 parts by weight of AFCONAA-0571 anti-settling agent, 30 parts by weight of pigeon talc, 5 parts by weight of BYK-314 leveling agent, 3 parts by weight of BYK-077 defoaming agent, 4 parts by weight of BYK-ANTI-TERRA-204 wetting and dispersing agent, 45 parts by weight of xylene and 5 parts by weight of n-butanol into a container in sequence, stir for 0.5 h, grind and disperse with a sand mill until the fineness is ≤40 μm, filter the material, seal and package to obtain component A;

[0076] (2) In a container, 100 parts by weight of γ-aminopropyltriethoxysilane and 50 parts by weight of BYK-4512 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0077] (3) The component A and component B prepared above were mixed in a weight ratio of A:B=100:7 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0078] Example 5

[0079] (1) 87 parts by weight of silicone resin, 13 parts by weight of epoxy modified silicone resin, 30 parts by weight of titanium dioxide R706, 6 parts by weight of copper chrome black 2852, 70 parts by weight of Huayuan wet-process muscovite 1250 mesh, 2.5 parts by weight of AFCONAA-0571 anti-settling agent, 40 parts by weight of pigeon talc powder, 4.5 parts by weight of BYK-314 leveling agent, 3.5 parts by weight of BYK-077 defoaming agent, 3.2 parts by weight of

[0080] BYK-ANTI-TERRA-204 wetting and dispersing agent, 45 parts by weight of xylene and 5 parts by weight of n-butanol were stirred for 0.5 h, and ground and dispersed with a sand mill until the fineness was ≤ 40 μm. The material was filtered and sealed to obtain component A.

[0081] (2) In a container, 100 parts by weight of γ-aminopropyltriethoxysilane and 40 parts by weight of BYK-4512 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0082] (3) The component A and component B prepared above were mixed in a weight ratio of A:B=100:10 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0083] Example 6

[0084] (1) 91.3 parts by weight of silicone resin, 8.7 parts by weight of polyurethane modified silicone resin, 40 parts by weight of titanium dioxide R706, 8 parts by weight of copper chrome black 2852, 50 parts by weight of Huayuan wet-process muscovite 1250 mesh, 3 parts by weight of Japanese Kusunoki 420-20 anti-settling agent, 40 parts by weight of pigeon talc, 4 parts by weight of TEGO-410 leveling agent, 2.3 parts by weight of AFCONA-A2020 defoaming agent, 3.2 parts by weight of Disponer903 wetting and dispersing agent, 0.5 parts by weight of dibutyltin dilaurate, 35 parts by weight of xylene and 5 parts by weight of butyl acetate were added to a container in sequence, stirred for 0.5 h, ground and dispersed with a sand mill until the fineness was ≤40 μm, filtered out, and sealed and packaged to obtain component A;

[0085] (2) In a container, 100 parts by weight of γ-mercaptopropyltriethoxysilane and 60 parts by weight of BYK-C8001 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0086] (3) The component A and component B prepared above were mixed in a weight ratio of A:B=100:4 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0087] Example 7

[0088] (1) 91.3 parts by weight of silicone resin, 8.7 parts by weight of polyester modified silicone resin, 40 parts by weight of titanium dioxide R706, 8 parts by weight of copper chrome black 2852, 50 parts by weight of Huayuan wet-process muscovite 1250 mesh, 3 parts by weight of AFCONA A-0571 anti-settling agent, 40 parts by weight of pigeon talc, 4 parts by weight of AFCONA A-3236 leveling agent, 2.3 parts by weight of TEGO-Airex 900 defoaming agent, 3.2 parts by weight of Disponer 903 wetting and dispersing agent, 3 parts by weight of triethylamine, 35 parts by weight of xylene and 5 parts by weight of butyl acetate were added to a container in sequence, stirred for 0.5 h, ground and dispersed with a sand mill until the fineness was ≤40 μm, filtered out, and sealed and packaged to obtain component A;

[0089] (2) In a container, 100 parts by weight of γ-glycidyloxypropyltrimethoxysilane and 60 parts by weight of BYK-C8001 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0090] (3) The component A and component B prepared above were mixed in a weight ratio of A:B=100:4 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0091] Example 8

[0092] (1) Add 91.3 parts by weight of silicone resin, 8.7 parts by weight of acrylic modified silicone resin, 40 parts by weight of titanium dioxide R706, 8 parts by weight of copper chrome black 2852, 50 parts by weight of Huayuan wet-process muscovite 1250 mesh, 3 parts by weight of Japanese Kusunoki 420-20 anti-settling agent, 40 parts by weight of pigeon talc, 4 parts by weight of BYK-314 leveling agent, 2.3 parts by weight of AFCONA-A2020 defoaming agent, 3.2 parts by weight of BYK-ANTI-TERRA-204 wetting and dispersing agent, 3 parts by weight of triethylamine, 45 parts by weight of xylene and 5 parts by weight of propylene glycol methyl ether acetate into a container in sequence, stir for 0.5 h, grind and disperse with a sand mill until the fineness is ≤40 μm, filter the material, seal and package to obtain component A;

[0093] (2) In a container, 100 parts by weight of γ-glycidyloxypropyltrimethoxysilane and 70 parts by weight of BYK-C8001 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0094] (3) The component A and component B prepared above were mixed in a weight ratio of A:B=100:4 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0095] Comparative Example 1

[0096] (1) Add 100 parts by weight of silicone resin, 40 parts by weight of titanium dioxide R706, 8 parts by weight of copper chrome black 2852, 50 parts by weight of Huayuan wet-process muscovite 1250 mesh, 3 parts by weight of AFCONA A-0571 anti-settling agent, 40 parts by weight of pigeon talc, 4 parts by weight of BYK-314 leveling agent, 2.3 parts by weight of BYK-077 defoaming agent, 3.2 parts by weight of BYK-ANTI-TERRA-204 wetting and dispersing agent, 35 parts by weight of xylene and 5 parts by weight of n-butanol into a container in sequence, stir for 0.5 h, grind and disperse with a sand mill until the fineness is ≤40 μm, filter the material, seal and package to obtain component A;

[0097] (2) In a container, 100 parts by weight of γ-aminopropyltriethoxysilane and 60 parts by weight of BYK-4512 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0098] (3) The component A and component B prepared above were mixed in a weight ratio of A:B=100:5 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0099] Comparative Example 2

[0100] (1) Add 100 parts by weight of silicone resin, 40 parts by weight of titanium dioxide R706, 8 parts by weight of copper chrome black 2852, 50 parts by weight of Huayuan wet-process muscovite 1250 mesh, 3 parts by weight of Japanese Kusunoki 420-20 anti-settling agent, 40 parts by weight of pigeon talc, 4 parts by weight of TEGO-410 leveling agent, 2.3 parts by weight of AFCONA-A2020 defoaming agent, 3.2 parts by weight of Disponer903 wetting and dispersing agent, 0.5 parts by weight of dibutyltin dilaurate, 35 parts by weight of xylene and 5 parts by weight of butyl acetate into a container in sequence, stir for 0.5 h, grind and disperse with a sand mill until the fineness is ≤40 μm, filter the material, seal and package to obtain component A;

[0101] (2) In a container, 100 parts by weight of γ-mercaptopropyltriethoxysilane and 60 parts by weight of BYK-C8001 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0102] (3) The component A and component B prepared above were mixed in a weight ratio of A:B=100:4 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0103] Comparative Example 3

[0104] (1) Add 100 parts by weight of epoxy modified silicone resin, 40 parts by weight of titanium dioxide R706, 8 parts by weight of copper chrome black 2852, 50 parts by weight of Huayuan wet-process muscovite 1250 mesh, 3 parts by weight of AFCONA A-0571 anti-settling agent, 40 parts by weight of pigeon talc, 4 parts by weight of BYK-314 leveling agent, 2.3 parts by weight of BYK-077 defoaming agent, 3.2 parts by weight of BYK-ANTI-TERRA-204 wetting and dispersing agent, 35 parts by weight of xylene and 5 parts by weight of n-butanol into a container in sequence, stir for 0.5 h, grind and disperse with a sand mill until the fineness is ≤40 μm, filter the material, seal and package to obtain component A;

[0105] (2) In a container, 100 parts by weight of γ-aminopropyltriethoxysilane and 60 parts by weight of BYK-4512 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0106] (3) The components A and B prepared above were mixed in a weight ratio of A:B=100:5 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0107] Comparative Example 4

[0108] (1) Add 91.3 parts by weight of silicone resin, 8.7 parts by weight of epoxy modified silicone resin, 40 parts by weight of titanium dioxide R706, 8 parts by weight of copper chrome black 2852, 50 parts by weight of mica powder (Huayuan wet-process muscovite 1250 mesh), 3 parts by weight of AFCONA A-0571 anti-settling agent, 40 parts by weight of talc powder (pigeon talc powder), 4 parts by weight of BYK-314 leveling agent, 2.3 parts by weight of BYK-077 defoaming agent, 3.2 parts by weight of BYK-ANTI-TERRA-204 wetting and dispersing agent, 35 parts by weight of xylene and 5 parts by weight of n-butanol into a container in sequence, stir for 0.5 h, grind and disperse with a sand mill until the fineness is ≤40 μm, filter the material, seal and package to obtain component A;

[0109] (2) In a container, 100 parts by weight of γ-aminopropyltriethoxysilane and 60 parts by weight of BYK-4512 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0110] (3) The component A and component B prepared above and the HDI trimer were mixed in a weight ratio of A:B = 100:5:0.75 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0111] Comparative Example 5

[0112] (1) Add 91.3 parts by weight of silicone resin, 8.7 parts by weight of epoxy modified silicone resin, 40 parts by weight of titanium dioxide R706, 8 parts by weight of copper chrome black 2852, 50 parts by weight of mica powder (Huayuan wet-process muscovite 1250 mesh), 3 parts by weight of AFCONA A-0571 anti-settling agent, 40 parts by weight of talc powder (pigeon talc powder), 4 parts by weight of BYK-314 leveling agent, 2.3 parts by weight of BYK-077 defoaming agent, 3.2 parts by weight of BYK-ANTI-TERRA-204 wetting and dispersing agent, 35 parts by weight of xylene and 5 parts by weight of n-butanol into a container in sequence, stir for 0.5 h, grind and disperse with a sand mill until the fineness is ≤40 μm, filter the material, seal and package to obtain component A;

[0113] (2) In a container, 100 parts by weight of polyamide and 50 parts by weight of BYK-4512 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0114] (3) The components A and B prepared above were mixed in a weight ratio of A:B=100:10 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0115] Comparative Example 6

[0116] (1) Add 100 parts by weight of epoxy modified silicone resin, 40 parts by weight of titanium dioxide R706, 8 parts by weight of copper chrome black 2852, 50 parts by weight of Huayuan wet-process muscovite 1250 mesh, 3 parts by weight of AFCONA A-0571 anti-settling agent, 40 parts by weight of pigeon talc, 4 parts by weight of BYK-314 leveling agent, 2.3 parts by weight of BYK-077 defoaming agent, 3.2 parts by weight of BYK-ANTI-TERRA-204 wetting and dispersing agent, 35 parts by weight of xylene and 5 parts by weight of n-butanol into a container in sequence, stir for 0.5 h, grind and disperse with a sand mill until the fineness is ≤40 μm, filter the material, seal and package to obtain component A;

[0117] (2) In a container, 100 parts by weight of polyamide and 50 parts by weight of BYK-4512 adhesion promoter were stirred for 0.5 h, filtered, and sealed to obtain component B;

[0118] (3) The components A and B prepared above were mixed in a weight ratio of A:B=100:10 to prepare a coating material; the coating material was applied to the surface of the substrate to obtain a coating with a thickness of 40 μm for performance testing.

[0119] The coatings prepared in the examples and comparative examples were subjected to performance tests. The test standards are shown in Table 1, and the test results are shown in Tables 2 and 3.

[0120] Table 1

[0121]

[0122]

[0123] Table 2

[0124]

[0125] Table 3

[0126]

[0127]

[0128] Compared to the examples, Comparative Examples 1, 2, and 3 used different resins; each used only one resin. Specifically, Comparative Examples 1 and 2 used only silicone resin, while Comparative Example 3 used only epoxy-modified silicone resin. Compared to the examples, Comparative Examples 4 and 5 used different curing agents; Comparative Example 4 used an HDI trimer curing agent, while Comparative Example 5 used a polyamide curing agent. Compared to the examples, Comparative Example 6 used different resins and curing agents; Comparative Example 6 used only epoxy-modified silicone resin and a polyamide curing agent. According to the data in Tables 2 and 3, it can be concluded that the curing temperature (50-80°C) of the examples is significantly lower than that of the comparative examples 1, 2, 3, 4, and 5 (200-250°C). Compared with the water resistance (small blistering of the coating), high temperature resistance of 350°C (ΔE=16.8, ΔE=18.2), resistance to damp heat for 2400h (slight cracking), and resistance to neutral salt spray for 2400h (1500h) of comparative examples 3 and 6, the water resistance (no blistering of the coating), high temperature resistance of 350°C (ΔE≤1.9), resistance to damp heat for 2400h (no cracking), and resistance to neutral salt spray for 2400h (≥2600h) of the examples are significantly improved. In other words, the coating prepared in the examples has the advantages of both low curing temperature and good thermal stability. This shows that the present invention solves the contradiction between low-temperature curing and poor thermal stability of silicone coatings by adopting a combination of specific resins and specific curing agents.

Claims

1. A low temperature curing organosilicon high temperature resistant coating, characterized in that: The organosilicon high temperature resistant coating is composed of independent components A and B; the weight ratio of component A to component B is 100:1-10; The A component includes a resin; the resin is composed of an organic silicone resin and a modified organic silicone resin, and the weight ratio of the organic silicone resin to the modified organic silicone resin is 100:5-15; The B component includes a curing agent and an adhesion promoter; the weight ratio of the curing agent to the adhesion promoter is 100:40-90; The modified silicone resin is selected from one of acrylic modified silicone resin, polyester modified silicone resin and polyurethane modified silicone resin; When the modified silicone resin is a polyurethane modified silicone resin, γ-mercaptopropyltriethoxysilane is selected as the curing agent; When the modified silicone resin is a polyester-modified silicone resin or an acrylic-modified silicone resin, γ-glycidyloxypropyltrimethoxysilane is selected as the curing agent.

2. The organosilicon high temperature resistant coating according to claim 1, characterized in that: The weight ratio of component A to component B is 100:2-6; or / and, The weight ratio of the organic silicone resin to the modified organic silicone resin is 100:8-11; or / and, The weight ratio of the curing agent to the adhesion promoter is 100:60-70.

3. The organosilicon high temperature resistant coating according to claim 1, characterized in that: The weight ratio of component A to component B is 100:3-5.

4. The organosilicon high temperature resistant coating according to claim 1, characterized in that: The component A further comprises mica powder; based on 100 parts by weight of the resin, the mica powder comprises 40-80 parts by weight.

5. The organosilicon high temperature resistant coating according to claim 4, characterized in that: 40-60 parts by weight of mica powder.

6. The high temperature resistant silicone coating according to claim 1, characterized in that: The component A further comprises titanium dioxide; based on 100 parts by weight of the resin, the amount of titanium dioxide is 30-60 parts by weight.

7. The high temperature resistant silicone coating according to claim 6, characterized in that: 30-50 parts by weight of titanium dioxide.

8. The organosilicon high temperature resistant coating according to claim 1, characterized in that: The component A further comprises copper chrome black; based on 100 parts by weight of the resin, the copper chrome black comprises 5-20 parts by weight.

9. The high temperature resistant silicone coating according to claim 8, characterized in that: Copper chrome black 8-12 parts by weight.

10. The high temperature resistant silicone coating according to claim 1, characterized in that: The A component further comprises the following components; each component is calculated based on 100 parts by weight of the resin: 30-50 parts by weight of talc; 3-6 parts by weight of leveling agent; 1.5-4 parts by weight of defoaming agent; 1.5-4 parts by weight of anti-settling agent; 2.5-5 parts by weight of wetting and dispersing agent; 30-60 parts by weight of solvent.

11. The high temperature resistant silicone coating according to claim 10, characterized in that: The solvent is selected from one or more of xylene, n-butanol, butyl acetate and propylene glycol methyl ether acetate.

12. A method for preparing the organosilicon high temperature resistant coating according to any one of claims 1 to 11, characterized in that: The preparation method includes: mixing and grinding the components of component A according to the weight ratio or weight parts to obtain component A, mixing the components of component B according to the weight parts to obtain component B, and mixing components A and B according to the weight ratio to obtain the organic silicon high-temperature resistant coating.

13. Use of the high-temperature resistant organosilicon coating according to any one of claims 1 to 11 in the fields of high-temperature chimneys, high-temperature pipelines, automobiles, and aircraft.

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