Solvent-free moisture-curing high-temperature-resistant paint as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of coatings, and particularly relates to solvent-free moisture-curing high-temperature-resistant paint as well as a preparation method and application thereof. The paint comprises a component A and a component B, the component A comprises organic silicon resin, a modified anti-rust pigment, glass powder and an auxiliary agent; the component B comprises a catalyst; the raw materials of the modified anti-rust pigment comprise a silane coupling agent and a silicon dioxide anti-rust pigment; the glass powder is prepared from the following components: SiO2, B2O3, SrO, ZrO2 and Li2O. The organic silicon resin and the silane coupling agent modified silicon dioxide anti-rust pigment are used as the modified anti-rust pigment, the glass powder, the auxiliaries and the catalyst are used for forming the paint, the paint can be cured under the normal-temperature moisture condition, a paint film or a coating formed after curing can resist the high temperature of 600 DEG C, the adhesive force of the paint film is kept stable, and meanwhile the corrosion resistance of the paint film is good. And the paint is solvent-free and has good environmental protection performance.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and particularly relates to a solvent-free moisture-curing high-temperature resistant paint and a preparation method and application thereof. Background Art

[0002] In the anti-corrosion coating design of high-temperature pipelines in power plants and petrochemical plants, especially on the surface of high-temperature pipelines above 200°C, silicone high-temperature resistant paint is widely used due to its anti-rust and decorative properties in high-temperature environments. However, when it comes to requirements for high temperatures above 400°C, silicone high-temperature resistant paint has certain application limitations, mainly the following points: 1. When using pure silicone resin paint that is resistant to temperatures above 400°C, it needs to be cured at high temperatures (between 150°C and 200°C) during drying, otherwise the hardness is low and it is difficult to transport on site; 2. Pure silicone resin paint has high requirements for substrate treatment and is difficult to apply to maintenance projects.

[0003] The prior art discloses a high-temperature resistant coating for thick-coating metal surfaces, which uses inorganic nano-ceramic resin and silicone resin as film-forming materials, and uses ultrafine powder of rare earth compounds, aerogel, hollow microspheres, and whisker silicon as powder systems. The polycondensation reaction of the silanol group of the inorganic nano-resin is utilized, and the coating can be cured at room temperature, thereby effectively improving the adhesion of the coating. The silicone resin improves the flexibility of the coating, and cracking will not occur at temperatures above 800°C. However, the technical solution does not examine the corrosion resistance of the coating, and has a narrow application range in corrosive environments. If the corrosion resistance is poor, the substrate is very likely to rust during shutdown of high-temperature equipment or pipelines.

[0004] The prior art also discloses a room temperature curing solvent-free organosilicon coating, the raw materials include organosilicon prepolymer A, polysiloxane B, curing agent C and pigment filler D, the organosilicon prepolymer A is cured at room temperature under the action of a catalyst, polysiloxane B is mainly used as a filler, the product has good adhesion and a smooth appearance. However, this technical solution does not examine the corrosion resistance of the coating after 600°C.

[0005] The common 600℃ resistant silicone high-temperature paint on the market usually needs to be baked and dried to achieve a certain level of temperature resistance, corrosion resistance and adhesion. However, this greatly limits the use scenarios of the coating and is inconvenient to use for large pipelines and equipment.

[0006] Therefore, there is an urgent need to provide a high-temperature resistant anti-corrosion paint, and the paint does not require high-temperature curing and can be cured at room temperature, which greatly expands the application scenarios of the paint. Summary of the invention

[0007] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention provides a solvent-free moisture-curing high-temperature resistant paint and its preparation method and application. The paint of the present invention does not need to be baked and cured, but can be cured at room temperature under the action of a catalyst, and has good high temperature resistance and corrosion resistance after curing.

[0008] The inventive concept of the present invention is: the present invention uses organic silicon resin, silane coupling agent modified silicon dioxide anti-rust pigment as modified anti-rust pigment, glass powder, additives, and catalyst to form a paint, the paint can be cured under normal temperature and humidity conditions, the paint film or coating formed after curing can withstand a high temperature of 600°C, the paint film adhesion remains stable, and the paint film has good anti-corrosion performance. The paint of the present invention is solvent-free and has good environmental performance.

[0009] A first aspect of the present invention provides a solvent-free moisture-curing high temperature resistant paint.

[0010] Specifically, a solvent-free moisture-curing high temperature resistant paint comprises a component A and a component B;

[0011] The component A comprises silicone resin, modified anti-rust pigment, glass powder and additives;

[0012] The B component includes a catalyst;

[0013] The raw materials of the modified anti-rust pigment include silane coupling agent and silicon dioxide anti-rust pigment;

[0014] The glass powder comprises SiO2, B2O3, SrO, ZrO2 and Li2O.

[0015] Preferably, the silicone resin is a phenyl methoxy-containing polysiloxane resin.

[0016] Preferably, the silicone resin has a siloxane bond content greater than 30% and a viscosity less than 200 cp at 25°C.

[0017] Preferably, the preparation process of the modified anti-rust pigment comprises: preparing a silane coupling agent into a liquid mixture, then adding a silicon dioxide anti-rust pigment, adjusting the pH to acidic, and heating the mixture for reaction to obtain the modified anti-rust pigment.

[0018] Preferably, the process of preparing the silane coupling agent into a liquid mixture is to mix the silane coupling agent, ethanol and water.

[0019] Preferably, the temperature of the heating reaction is 50-60°C, and the heating reaction time is 2-6h. More preferably, the temperature of the heating reaction is 55-60°C, and the heating reaction time is 4-6h.

[0020] Preferably, after the heating reaction is completed, the process of filtering, washing and drying is also included.

[0021] Preferably, the preparation process of the modified anti-rust pigment includes: mixing a silane coupling agent, ethanol and water to prepare a liquid mixture, then adding a silica anti-rust pigment, adjusting the pH to acidic, heating at 50-60°C for reaction for 2-6h, filtering, washing and drying to obtain the modified anti-rust pigment.

[0022] Preferably, the weight ratio of the silica anti-rust pigment, silane coupling agent, ethanol and water is (6-9): (2-4): (20-40): (4-8); more preferably, it is 7.5: (2-4): (20-40): (4-8).

[0023] Preferably, the silane coupling agent is vinyl tris(methoxyethoxy)silane.

[0024] Preferably, oxalic acid is used to adjust the pH.

[0025] Preferably, the drying temperature is 100-105° C., and the drying time is 2-3 hours.

[0026] The modified anti-rust pigment is a silicon dioxide anti-rust pigment, which uses silicon dioxide as a carrier and forms calcium-containing exchange silica gel through ion exchange, and has excellent high temperature resistance. At low temperatures, the silicon dioxide anti-rust pigment has a good anti-rust effect through adsorption and calcium ion exchange. When the high temperature exceeds 500°C, the coating after the silicon dioxide anti-rust pigment and the glass powder are sintered has good compatibility, and the anti-rust pigment still plays a good protective role.

[0027] The modified anti-rust pigment of the present invention improves the compatibility and stability of the anti-rust pigment in the organosilicon resin system.

[0028] Preferably, the glass powder also comprises at least one of BaO, MgO, CaO and Bi2O3.

[0029] The glass powder is a borate-based low-melting-point glass powder with good corrosion resistance and chemical stability.

[0030] Preferably, the composition of the glass powder, by weight, includes 42-65 parts of SiO2, 4-9 parts of B2O3, 3-14 parts of SrO2, 3-9 parts of ZrO2, 1-9 parts of Li2O, 0-22 parts of BaO, 0-8 parts of MgO, 0-10 parts of CaO, and 0-10 parts of Bi2O3; further preferably, the composition of the glass powder, by weight, includes 45-60 parts of SiO2, 4.5-8 parts of B2O3, 4-12 parts of SrO, 4-8 parts of ZrO2, 2-8 parts of Li2O, 0-20 parts of BaO, 0-8 parts of MgO, 0-10 parts of CaO, and 0-10 parts of Bi2O3.

[0031] Preferably, the glass powder is formed by mixing low-melting-point glass powders FD56 and FD66A of Guangdong Qichen in equal proportions. The melting temperature of low-melting-point glass powder FD56 is 350-400°C, and the melting temperature of low-melting-point glass powder FD66A is 500°C. The low-melting-point glass powders are matched in a gradient manner, and the glass powders melt in different temperature stages under a temperature-resistant environment, which is conducive to a wider temperature-resistant range of the coating.

[0032] Preferably, the particle size of the glass powder is above 1500 mesh, for example, 1500-2000 mesh.

[0033] The above-mentioned glass powder is a compound glass powder. At different temperatures, the glass powder can be used as a binder after melting to improve the high temperature resistance and corrosion resistance of the coating or paint film.

[0034] Preferably, the catalyst is selected from at least one of butyl titanate and aminosilane. The catalyst promotes the moisture curing reaction of methoxy groups in the silicone resin.

[0035] Preferably, the auxiliary agent includes at least one of an anti-settling agent, a dispersant, a defoamer, a filler, and aluminum powder, and more preferably includes an anti-settling agent, a dispersant, a defoamer, a filler, and aluminum powder. Aluminum powder has good heat resistance and strong thermal conductivity.

[0036] Preferably, the dispersant and defoamer are conventional commercial products, for example, the dispersant is DISPERBYK-110 and the defoamer is BYK-1760.

[0037] Preferably, the anti-settling agent is a conventional commercial product, such as Guangzhou Huifu Research Institute's fumed silica, model HB151.

[0038] Preferably, the filler includes at least one of mica powder and talc powder.

[0039] Preferably, the paint comprises component A and component B;

[0040] The component A comprises, by weight, 30-55 parts of silicone resin, 5-15 parts of modified anti-rust pigment, 8-18 parts of glass powder, and 10-35 parts of additives;

[0041] The B component includes 1-2 parts of catalyst by weight.

[0042] Preferably, the weight ratio of component A to component B is (20-100): 1, more preferably (50-100): 1. When the paint is used, component A and component B are mixed and then cured at room temperature with a relative humidity of 50-80%.

[0043] Preferably, the paint comprises component A and component B;

[0044] The component A comprises, by weight, 40-50 parts of organic silicone resin, 6-10 parts of modified anti-rust pigment, 10-15 parts of glass powder, and 20.4-28.2 parts of additives;

[0045] The B component includes 1-2 parts of catalyst by weight.

[0046] Preferably, the additives in component A, by weight, include 1-4 parts of anti-settling agent, 1-2.5 parts of dispersant, 0.4-1 parts of defoaming agent, 10-20 parts of filler, and 1-6 parts of aluminum powder; further preferably, the additives in component A, by weight, include 1-2 parts of anti-settling agent, 1-1.5 parts of dispersant, 0.4-0.7 parts of defoaming agent, 14-18 parts of filler, and 4-6 parts of aluminum powder.

[0047] The second aspect of the present invention provides a method for preparing a solvent-free moisture-curing high temperature resistant paint.

[0048] Specifically, a method for preparing a solvent-free moisture-curing high temperature resistant paint comprises the following steps:

[0049] The raw materials of component A are mixed to obtain the component A; a catalyst is taken as component B, and the component A and component B constitute the paint.

[0050] Preferably, the preparation method comprises the following steps:

[0051] Preparation of component A: Add silicone resin, dispersant, defoamer, modified anti-rust pigment, anti-settling agent, filler and glass powder into a kettle, stir evenly and grind to a fineness of no more than 40 microns, then add aluminum powder and stir evenly at a low speed, discharge the material, and obtain component A;

[0052] The catalyst is taken as the B component, and the A component and the B component constitute the paint.

[0053] A third aspect of the present invention provides a use of a solvent-free moisture-curing high temperature resistant paint.

[0054] A chemical equipment comprises a coating formed by the above solvent-free moisture-curing high-temperature resistant paint.

[0055] Preferably, the chemical equipment includes a reaction kettle, a container or a pipeline.

[0056] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0057] (1) The present invention uses organic silicon resin, silane coupling agent modified silica anti-rust pigment as modified anti-rust pigment, glass powder, additives, and catalyst to form a paint, which can be cured under normal temperature and humidity conditions. The paint film or coating formed after curing can withstand a high temperature of 600°C, the adhesion of the paint film remains stable, and the anti-corrosion performance of the paint film is good. The paint of the present invention is solvent-free and has good environmental performance.

[0058] (2) The paint of the present invention, by combining low-melting-point glass powder and using modified anti-rust pigments, can make the coating formed by the paint resistant to 600° C., maintain stable adhesion, and have good anti-corrosion performance.

[0059] (3) The paint of the present invention can be used for the renovation of high temperature resistant paint without being too limited in the treatment and drying of the substrate; the low VOC content helps to reduce the risk during construction. DETAILED DESCRIPTION

[0060] In order to make the technical scheme of the present invention more clearly understood by those skilled in the art, the following embodiments are listed for illustration. It should be pointed out that the following embodiments do not limit the protection scope of the present invention.

[0061] Unless otherwise specified, the raw materials, reagents or devices used in the following examples can be obtained from conventional commercial sources or by existing known methods.

[0062] The sources of raw materials used in the following examples are as follows:

[0063] The silicone resin is provided by Hubei Longsheng Sihai Company, model SH-3021, which is a phenyl methoxy-containing polysiloxane resin.

[0064] The dispersant is DISPERBYK-110; the defoamer is BYK-1760.

[0065] The anti-settling agent is provided by Guangzhou Huifu Research Institute and is fumed silica, model HB151.

[0066] The glass powder is Guangdong Qichen's low melting point glass powder FD56 and FD66A.

[0067] The silica anti-rust pigment is provided by Shanghai Yingqi Company, model number is YA01.

[0068] The modified antirust filler used in the following examples was prepared by the following method:

[0069] The preparation process of the modified anti-rust pigment includes: mixing vinyl tri(methoxyethoxy)silane, ethanol and water to prepare a liquid mixture, and then adding silica anti-rust pigment, the weight ratio of silica anti-rust pigment, vinyl tri(methoxyethoxy)silane, ethanol and water is 7.5:3:30:7, adjusting the pH to 4 with oxalic acid, heating at 60°C for reaction for 6 hours, filtering, washing, and drying at 105°C for 3 hours to obtain the modified anti-rust pigment.

[0070] Example 1

[0071] A solvent-free moisture-curing high temperature resistant paint, comprising component A and component B;

[0072] Component A, by weight, includes 44 parts of silicone resin, 8 parts of modified anti-rust pigment, 12 parts of glass powder, 1.5 parts of anti-settling agent, 1 part of dispersant, 0.5 parts of defoamer, 16 parts of filler (composed of mica powder and talc powder in a weight ratio of 1:1), and 5 parts of aluminum powder;

[0073] Component B is 1.5 parts of butyl titanate catalyst;

[0074] The glass powder is composed of Guangdong Qichen's low-melting point glass powder FD56 and FD66A in a weight ratio of 1:1.

[0075] A method for preparing a solvent-free moisture-curing high temperature resistant paint comprises the following steps:

[0076] Preparation of component A: Add silicone resin, dispersant, defoamer, modified anti-rust pigment, anti-settling agent, filler and glass powder into a kettle, stir evenly and grind to a fineness of no more than 40 microns, then add aluminum powder and stir evenly at a low speed, discharge the material, and obtain component A;

[0077] The butyl titanate catalyst is taken as the B component, and the A component and the B component constitute the paint.

[0078] Example 2

[0079] A solvent-free moisture-curing high temperature resistant paint, comprising component A and component B;

[0080] Component A, by weight, includes 40 parts of silicone resin, 6 parts of modified anti-rust pigment, 10 parts of glass powder, 1.5 parts of anti-settling agent, 1 part of dispersant, 0.5 parts of defoamer, 16 parts of filler (composed of mica powder and talc powder in a weight ratio of 1:1), and 5 parts of aluminum powder;

[0081] Component B is 1.5 parts of butyl titanate catalyst;

[0082] The glass powder is composed of Guangdong Qichen's low-melting point glass powder FD56 and FD66A in a weight ratio of 1:1.

[0083] A method for preparing a solvent-free moisture-curing high temperature resistant paint comprises the following steps:

[0084] Preparation of component A: Add silicone resin, dispersant, defoamer, modified anti-rust pigment, anti-settling agent, filler and glass powder into a kettle, stir evenly and grind to a fineness of no more than 40 microns, then add aluminum powder and stir evenly at a low speed, discharge the material, and obtain component A;

[0085] The butyl titanate catalyst is taken as the B component, and the A component and the B component constitute the paint.

[0086] Example 3

[0087] A solvent-free moisture-curing high temperature resistant paint, comprising component A and component B;

[0088] Component A, by weight, includes 50 parts of silicone resin, 10 parts of modified anti-rust pigment, 15 parts of glass powder, 1.5 parts of anti-settling agent, 1 part of dispersant, 0.5 parts of defoamer, 16 parts of filler (composed of mica powder and talc powder in a weight ratio of 1:1), and 5 parts of aluminum powder;

[0089] Component B is 1.5 parts of butyl titanate catalyst;

[0090] The glass powder is composed of Guangdong Qichen's low-melting point glass powder FD56 and FD66A in a weight ratio of 1:1.

[0091] A method for preparing a solvent-free moisture-curing high temperature resistant paint comprises the following steps:

[0092] Preparation of component A: Add silicone resin, dispersant, defoamer, modified anti-rust pigment, anti-settling agent, filler and glass powder into a kettle, stir evenly and grind to a fineness of no more than 40 microns, then add aluminum powder and stir evenly at a low speed, discharge the material, and obtain component A;

[0093] The butyl titanate catalyst is taken as the B component, and the A component and the B component constitute the paint.

[0094] Comparative Example 1

[0095] Compared with Example 1, the difference in Comparative Example 1 is that an equal amount of modified zinc phosphate antirust pigment (the preparation process of the modified zinc phosphate antirust pigment is similar to the preparation process of the modified antirust pigment in Example 1, the only difference is that an equal amount of zinc phosphate antirust pigment is used instead of the silicon dioxide antirust pigment) replaces the modified antirust pigment in Example 1, and the other components and processes are the same as Example 1.

[0096] Comparative Example 2

[0097] Compared with Example 1, the difference of Comparative Example 2 is that an equal amount of low-melting-point glass powder FD76 (melting temperature is 600° C.) is used to replace the glass powder in Example 1, and other components and processes are the same as those in Example 1.

[0098] Comparative Example 3

[0099] Compared with Example 1, the difference of Comparative Example 3 is that the silicone resin in Example 1 is replaced by an equal amount of acrylic acid-modified silicone resin (the resin does not contain phenyl methoxy group), and other components and processes are the same as those in Example 1.

[0100] Product effect testing

[0101] The paints prepared in the above Examples 1-3 and Comparative Examples 1-3 were cured at room temperature and a relative humidity of 70%. After the paint films were formed, the salt spray resistance, adhesion, heat resistance, moisture and heat resistance, surface drying time, paint film appearance, and the non-volatile content of the corresponding paints were tested. The results are shown in Tables 1 and 2.

[0102] The test standards for different indicators are as follows:

[0103] Salt spray resistance: GB / T 1771;

[0104] Heat resistance: GB / T 1735;

[0105] Salt spray resistance (600℃, 6h): After the sample is baked at 600℃ for 6h, the salt spray resistance is tested;

[0106] Moisture and heat resistance: GB / T 1740;

[0107] Surface drying time: GB / T 1728;

[0108] Paint film appearance: visual;

[0109] Non-volatile matter content: GB / T 1725.

[0110] Table 1

[0111]

[0112]

[0113] Table 2

[0114]

[0115] It can be seen from Table 1-2 that the paint film formed by the paint prepared in the embodiment of the present invention has better high temperature resistance and corrosion resistance.

Claims

1. A paint, characterized in that: It includes component A and component B; The component A comprises silicone resin, modified anti-rust pigment, glass powder and additives; The B component includes a catalyst; The raw materials of the modified anti-rust pigment include silane coupling agent and silicon dioxide anti-rust pigment; The glass powder comprises SiO2, B2O3, SrO, ZrO2 and Li2O.

2. The paint according to claim 1, characterized in that The organic silicone resin is a phenyl methoxy-containing polysiloxane resin.

3. The paint according to claim 1, characterized in that The preparation process of the modified anti-rust pigment comprises: preparing a silane coupling agent into a liquid mixture, then adding the silicon dioxide anti-rust pigment, adjusting the pH to acidic, heating and reacting to obtain the modified anti-rust pigment.

4. The paint according to claim 3, characterized in that The temperature of the heating reaction is 50-60° C., and the time of the heating reaction is 2-6 hours; and / or, after the heating reaction is completed, the process of filtering, washing and drying is also included.

5. The paint according to claim 4, characterized in that The preparation process of the modified anti-rust pigment includes: mixing a silane coupling agent, ethanol and water to prepare a liquid mixture, then adding a silicon dioxide anti-rust pigment, adjusting the pH to acidic, heating at 50-60° C. for reaction for 2-6 hours, filtering, washing and drying to obtain the modified anti-rust pigment.

6. The paint according to claim 1, characterized in that The glass powder also includes at least one of BaO, MgO, CaO and Bi2O3.

7. The paint according to claim 6, characterized in that The composition of the glass powder, by weight, includes 42-65 parts of SiO2, 4-9 parts of B2O3, 3-14 parts of SrO, 3-9 parts of ZrO2, 1-9 parts of Li2O, 0-22 parts of BaO, 0-8 parts of MgO, 0-10 parts of CaO, and 0-10 parts of Bi2O3; and / or the auxiliary agent includes at least one of an anti-settling agent, a dispersant, a defoaming agent, a filler, and aluminum powder.

8. The paint according to claim 1, characterized in that The paint comprises component A and component B; The component A comprises, by weight, 30-55 parts of silicone resin, 5-15 parts of modified anti-rust pigment, 8-18 parts of glass powder, and 10-35 parts of additives; The B component includes 1-2 parts of catalyst by weight.

9. The method for preparing the paint according to any one of claims 1 to 8, characterized in that: The following steps are involved: The raw materials of component A are mixed to obtain the component A; a catalyst is taken as component B, and the component A and component B constitute the paint.

10. A chemical equipment, characterized in that: A coating formed by the paint according to any one of claims 1 to 8.

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