Coating, preparation method and application

Abstract

The invention discloses a coating, a preparation method and application, and relates to the technical field of coating preparation. Raw materials of the coating comprise a water-based acrylic copolymer emulsion, nano porous microspheres, a nano functional filler, an anti-rust pigment filler and a rust conversion agent, and the nano functional filler comprises at least one of acidified multi-walled carbon nanotubes and hydroxylated barium titanate. The coating disclosed by the invention is low in heat conductivity coefficient, heat dissipation loss can be effectively reduced when the coating is coated on the outer surface of equipment or a pipeline, meanwhile, a coating layer formed by adopting various nanoscale fillers is compact and high in corrosion resistance, and the equipment or the pipeline in a coastal area can be effectively prevented from being corroded; in addition, the coating disclosed by the invention is high in adhesive force, can be suitable for special-shaped equipment to which a traditional anti-corrosion heat-insulating material is difficult to apply, and is wide in application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of coating preparation, and in particular to a coating, a preparation method and application thereof. Background Art

[0002] A large number of pipelines and equipment in thermal power plants need to be insulated, cold-insulated, and have achieved the purpose of saving energy and preventing a large amount of heat loss. At present, the traditional insulation materials used in this field include calcium carbonate, perlite, glass wool, rock wool, aluminum silicate, and foamed polyurethane. The above different materials have certain limitations in practical application. For example, the structural strength is poor, and the coating after coating is easy to form a phenomenon of thin top and thick bottom and thermal seams; the coating of the pipeline's special-shaped structures such as valves, elbows, and supports cannot be completely covered; the poor uniformity of the insulation material leads to unstable thermal conductivity, causing the coating to hollow out and produce "thermal bridges", and the insulation effect will also deteriorate; the insulation material has poor chemical resistance, especially the strong corrosiveness of seawater in the coastal environment is easy to damage the insulation coating. Therefore, it is necessary to design a coating for the integrated anti-corrosion and thermal insulation of pipelines in coastal environments. Summary of the invention

[0003] The main purpose of the present invention is to develop a coating that can withstand seawater corrosion and has low thermal conductivity, good thermal insulation, good construction performance and strong adhesion, which can be used for thermal insulation and corrosion protection needs of pipelines, equipment, etc. in thermal power plants in coastal environments.

[0004] To achieve the above-mentioned purpose, the present invention proposes a coating, characterized in that the coating comprises the following raw materials in parts by weight: 5 to 30 parts of water-based acrylic copolymer emulsion; 10 to 40 parts of nanoporous microspheres; 0.5 to 3 parts of nanofunctional fillers; 5 to 20 parts of anti-rust color fillers; 0.5 to 3 parts of rust converters; 20 to 40 parts of water; the nanofunctional fillers comprise at least one of acidified multi-walled carbon nanotubes and hydroxylated barium titanate.

[0005] In one embodiment, the acidified multi-walled carbon nanotubes include at least one of acidified multi-walled carbon nanotubes having a length of less than 10 μm, acidified multi-walled carbon nanotubes having a length of 10 to 30 μm, and acidified multi-walled carbon nanotubes having a length of 30 to 100 μm.

[0006] In one embodiment, the barium titanate hydroxylate includes at least one of barium titanate hydroxylate having a particle size of 0.2 to 0.5 μm, barium titanate hydroxylate having a particle size of 0.5 to 1 μm, and barium titanate hydroxylate having a particle size of 1 to 100 μm.

[0007] In one embodiment, the aqueous acrylic copolymer emulsion includes at least one of pure acrylic emulsion, styrene acrylic emulsion and silicone acrylic emulsion.

[0008] In one embodiment, the nanoporous microspheres include at least one of nano-titanium dioxide microspheres, nano-silicon dioxide microspheres, nano-calcium carbonate microspheres, and nano-titanium dioxide / silicon dioxide microspheres.

[0009] In one embodiment, the average particle size of the nanoporous microspheres is 500-2000 nm.

[0010] In one embodiment, the specific surface area of ​​the nanoporous microspheres is 300 to 800 m 2 / g.

[0011] In one embodiment, the nanoporous microspheres have an average internal pore diameter of 5 to 40 nm.

[0012] In one embodiment, the anti-rust pigment filler is an ion exchange anti-rust pigment filler; the anti-rust pigment filler includes at least one of aluminum tripolyphosphate, zinc phosphate, zinc aluminum phosphate, molybdate, and precipitated barium sulfate.

[0013] In one embodiment, the coating further comprises an auxiliary agent, and the auxiliary agent comprises the following components in parts by weight: defoaming agent: 0.1 to 1 part; anti-settling agent: 0.1 to 1 part; diluent: 0.1 to 10 parts.

[0014] The present invention also provides a method for preparing the coating, which comprises the following steps:

[0015] S10, mixing and dispersing the aqueous acrylic copolymer emulsion, the diluent and water to obtain component A;

[0016] S20, mixing and dispersing the remaining raw materials and adding them to the component A obtained in step S10, stirring, dispersing and standing to obtain a coating.

[0017] The invention also proposes the application of the coating in the anti-corrosion and heat preservation of coal powder pipelines in coastal power plants.

[0018] The technical solution of the present invention designs a coating with both anti-corrosion and thermal insulation properties. The coating of the present invention uses acrylic copolymer emulsion as a matrix material, and adds nanoporous microspheres and nanofunctional fillers as main fillers to maintain the thermal conductivity of the coating at a relatively low level. The coating of the present invention can be applied to the surface of equipment below 180°C, and can reduce the outer surface temperature of equipment / pipelines at 120°C to 55-60°C, greatly reducing the heat dissipation loss of the equipment; at the same time, the nanofunctional filler can also make the solids in the coating, such as fillers, evenly dispersed, so that the coating has better uniformity, better coating effect, better density of the formed coating, less coating time, and is suitable for special-shaped equipment that is difficult to apply traditional anti-corrosion and thermal insulation materials; the coating of the present invention is a water-based single-component coating, does not contain harmful organic volatiles, corrosive media that can be hydrolyzed twice, etc., is pollution-free to the environment, and has a combustion performance grade of Class A. DETAILED DESCRIPTION

[0019] 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.

[0020] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0021] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] The technical problem solved by the present invention is that the materials used for the thermal insulation layer of the pipelines of the existing thermal power plants in the coastal environment have technical problems such as poor coating structure strength, unstable thermal conductivity, poor corrosion resistance, etc.

[0023] In order to solve the above technical problems, a coating is designed that can withstand seawater corrosion and has low thermal conductivity, good thermal insulation, good construction performance and strong adhesion, so as to meet the insulation and anti-corrosion needs of pipelines and equipment in thermal power plants in coastal environments.

[0024] The invention provides a coating, which comprises the following raw materials in parts by weight: 5 to 30 parts of water-based acrylic copolymer emulsion; 10 to 40 parts of nanoporous microspheres; 0.5 to 3 parts of nano-functional fillers; 5 to 20 parts of anti-rust color fillers; 0.5 to 3 parts of rust converters; and 20 to 40 parts of water. The nano-functional fillers comprise at least one of acidified multi-walled carbon nanotubes and hydroxylated barium titanate.

[0025] It should be noted that the present invention adopts water-based acrylic copolymer emulsion as the base material of the coating, and this type of emulsion has good adhesion to coating substrates such as metal, wood, concrete, plastic, etc.; acrylic copolymer has good UV resistance and weather resistance, fast drying speed, good leveling, and easy construction. The formed coating has a certain flexibility and can withstand slight deformation of the substrate without cracking or peeling; the water-based acrylic copolymer emulsion is a water-based single-component base material, does not contain harmful organic volatiles, does not contain corrosive media that can be hydrolyzed twice, and does not pollute the environment.

[0026] Optionally, the aqueous acrylic copolymer emulsion is a nano-scale aqueous acrylic copolymer emulsion, including but not limited to nano-scale pure acrylic emulsion, nano-scale styrene acrylic emulsion and nano-scale silicone acrylic emulsion. The nano-scale emulsion is particularly suitable for penetrating coatings of porous coating substrates, has a low film-forming temperature and good viscosity, and is particularly suitable for coating non-planar surfaces such as pipeline surfaces and special-shaped parts.

[0027] It should also be noted that the three fillers of nanoporous microspheres, nanofunctional fillers and anti-rust pigment fillers are compounded in the present invention, thereby greatly improving the thermal insulation and anti-corrosion properties of the coating formed by the coating on the basis of the relevant properties of the base material. The nanoporous microspheres used in the present invention are inorganic nanoporous microspheres, which have high hardness and wear resistance. Due to their low density and small size, they are easy to disperse in the base material, and can improve the mechanical strength of the coating without affecting the flexibility of the coating; the pore structure in the nanoporous microspheres can effectively prevent heat conduction and reduce the thermal conductivity of the coating; the nanofunctional fillers in the present invention are inorganic nanoparticles with active functional groups such as hydroxyl and carboxyl groups on the surface. The nanofunctional fillers in the present invention can react with polar groups in the acrylic copolymer base material to form hydrogen bonds or other covalent bonds, thereby enhancing the interface bonding between the acrylic copolymer base material and the nanofunctional fillers and promoting the dispersion of the nanofunctional fillers in the base material; the anti-rust pigment fillers in the present invention are ion exchange anti-rust pigment fillers, which can intercept corrosive ions on the filler surface.

[0028] It should also be noted that the active functional groups on the surface of the nano-functional filler in the present invention can also form bonds with the nano-porous microspheres and the anti-rust pigment fillers, thereby further promoting the dispersion of the nano-porous microspheres and the anti-rust pigment fillers in the matrix material, thereby further enhancing the relevant properties of the coating; during the curing process of the coating, cross-linking can occur within the matrix material and between the matrix material and the filler, further enhancing the mechanical strength, corrosion resistance and other properties of the coating.

[0029] In one embodiment of the present invention, the acidified multi-walled carbon nanotubes include at least one of acidified multi-walled carbon nanotubes with a length less than 10 μm, acidified multi-walled carbon nanotubes with a length of 10-30 μm, and acidified multi-walled carbon nanotubes with a length of 30-100 μm.

[0030] It should be noted that the acidic multi-walled carbon nanotubes in the present invention are obtained by acidifying the multi-walled carbon nanotubes with a strong acid, so that active functional groups such as carboxyl, hydroxyl and carbonyl are introduced into the surface of the multi-walled carbon nanotubes. The above-mentioned active functional groups can cross-link or bond with the active functional groups in the matrix material and fillers such as nanoporous microspheres and anti-rust color fillers, promote the dispersion of the filler in the matrix material and improve the interfacial bonding force between the filler and the matrix material, thereby improving the strength, chemical corrosion resistance and thermal insulation properties of the coating.

[0031] It should also be noted that acidic multi-walled carbon nanotubes are usually obtained by surface treating multi-walled carbon nanotubes (MWCNTs) with strong acids. Multi-walled carbon nanotubes (MWCNTs) are tubular structural materials composed of multiple layers of carbon atoms. Multi-walled carbon nanotubes themselves have a high thermal conductivity, which can reach 3000W / (m·K) at room temperature. In the present invention, by adding acidic multi-walled carbon nanotubes of different lengths to the coating, shorter acidic multi-walled carbon nanotubes can be directly and evenly dispersed in the coating matrix material, and longer acidic multi-walled carbon nanotubes can form a discontinuous physical network structure in the coating, so that more pores are formed in the formed coating, thereby further reducing the thermal conductivity of the coating. At the same time, longer acidic multi-walled carbon nanotubes can serve as a reinforcing skeleton to improve the tensile strength and elastic modulus of the coating, and shorter acidic multi-walled carbon nanotubes can improve the uniformity and smoothness of the coating.

[0032] In one embodiment of the present invention, the method for preparing acidic multi-walled carbon nanotubes comprises the following steps:

[0033] Add multi-walled carbon nanotubes to 60-70wt% nitric acid, ultrasonically treat for 4-5h, cool to room temperature, filter out the residue, wash, and dry to obtain acidified multi-walled carbon nanotubes. It should be noted that the preparation method of acidic multi-walled carbon nanotubes in the present invention is not limited to the above process.

[0034] In one embodiment of the present invention, the acidified multi-walled carbon nanotubes include 40-60wt% of acidified multi-walled carbon nanotubes with a length less than 10 μm, 20-30wt% of acidified multi-walled carbon nanotubes with a length of 10-30 μm and 20-30wt% of acidified multi-walled carbon nanotubes with a length of 30-100 μm.

[0035] It should be noted that the present invention forms a special balance among the mechanical strength, flexibility and thermal insulation performance of the prepared coating by adding the above-mentioned acidic multi-walled carbon nanotubes of different lengths in different proportions to the coating, thereby ensuring that the mechanical properties of the coating formed by the coating are better while ensuring the thermal insulation performance of the coating.

[0036] In one embodiment of the present invention, the barium titanate hydroxylate includes at least one of barium titanate hydroxylate with a particle size of 0.2-0.5 μm, barium titanate hydroxylate with a particle size of 0.5-1 μm, and barium titanate hydroxylate with a particle size of 1-100 μm.

[0037] It should be noted that the hydroxylated barium titanate in the present invention is a barium titanate surface that is treated with a specific chemical process to introduce hydroxyl groups, so that the hydroxylated barium titanate can be cross-linked or bonded with active functional groups in the matrix material and fillers such as nanoporous microspheres and anti-rust pigment fillers, thereby further enhancing the relevant properties of the coating. In the present invention, by adding hydroxylated barium titanate of different particle sizes to the coating, the hydroxylated barium titanate of smaller particle size can form more hydrogen bonds or covalent bonds with the polymer matrix due to its larger specific surface area, further enhancing the interfacial bonding force; the hydroxylated barium titanate of larger particle size can form a more effective physical support structure in the coating and improve the wear resistance of the coating, providing higher mechanical strength.

[0038] In one embodiment of the present invention, the preparation process of hydroxylated barium titanate comprises the following steps:

[0039] Add barium titanate to hydrogen peroxide, perform ultrasonic treatment, and then heat to 105°C for reaction, filter out the residue, wash, and dry to obtain hydroxylated barium titanate. It should be noted that the preparation method of hydroxylated barium titanate in the present invention is not limited to the above process.

[0040] In one embodiment of the present invention, the barium hydroxylated titanate comprises at least one of 30-50wt% of barium hydroxylated titanate with a particle size of 0.2-0.5 μm, 30-60wt% of barium hydroxylated titanate with a particle size of 0.5-1 μm and 10-20wt% of barium hydroxylated titanate with a particle size of 1-100 μm.

[0041] It should be noted that the present invention forms a special balance between the dispersibility of the barium titanate hydroxylate in the matrix material, the uniformity of the coating and the mechanical strength of the coating by adding the above-mentioned different proportions of barium titanate hydroxylate corresponding to different lengths into the coating, so that the mechanical properties of the coating formed by the coating are better while ensuring good dispersibility of the barium titanate hydroxylate and good uniformity of the coating.

[0042] In one embodiment of the present invention, the nano-functional filler comprises acidified multi-walled carbon nanotubes and hydroxylated barium titanate in a weight ratio of (2-3):(0.5-1).

[0043] It should be noted that by adding a specific weight ratio of acidic multi-walled carbon nanotubes and hydroxylated barium titanate to the matrix material, the two can exert a synergistic effect to further optimize the thermal insulation, mechanical strength and weather resistance of the coating.

[0044] In one embodiment of the present invention, the aqueous acrylic copolymer emulsion includes at least one of pure acrylic emulsion, styrene acrylic emulsion and silicone acrylic emulsion.

[0045] It should be noted that pure acrylic emulsion is prepared by emulsion polymerization of acrylic ester monomers (such as butyl acrylate, methyl methacrylate, etc.), does not contain other types of monomers such as styrene, and is also called pure acrylic resin; styrene acrylic emulsion is prepared by emulsion polymerization of styrene and acrylic ester monomers (such as butyl acrylate, methyl methacrylate, etc.). Due to the presence of styrene monomer, the emulsion has better rigidity and hardness; silicone acrylic emulsion is prepared by emulsion polymerization of silicone monomers containing unsaturated bonds (such as siloxanes) and acrylic ester monomers (such as butyl acrylate, methyl methacrylate, etc.). It has the characteristics of high temperature resistance, weather resistance, and chemical resistance of silicone as well as the high color retention, flexibility and high adhesion of acrylic resin.

[0046] In one embodiment of the present invention, the aqueous acrylic copolymer emulsion is selected from Wantipro 0622, 8223, One of 4903 or AXILAT PR3500.

[0047] In one embodiment of the present invention, the nanoporous microspheres include at least one of nano-titanium dioxide microspheres, nano-silicon dioxide microspheres, nano-calcium carbonate microspheres and nano-titanium dioxide / silicon dioxide microspheres.

[0048] In one embodiment of the present invention, the average particle size of the nanoporous microspheres is 500-2000 nm.

[0049] It should be noted that the average particle size of the nanoporous microspheres in this embodiment can be any value among 500 nm, 1000 nm, 1200 nm, 1500 nm, 1600 nm and 2000 nm, as long as it is within the above range.

[0050] In one embodiment of the present invention, the specific surface area of ​​the nanoporous microspheres is 300 to 800 m 2 / g.

[0051] It should be noted that the specific surface area of ​​the nanoporous microspheres in this embodiment can be 300m 2 / g, 450m 2 / g、500m 2 / g、600m 2 / g and 800m 2 Any value of / g may be used as long as it falls within the above range.

[0052] In one embodiment of the present invention, the average internal pore diameter of the nanoporous microspheres is 5-40 nm.

[0053] It should be noted that the average internal pore diameter of the nanoporous microspheres in this embodiment can be any value among 5 nm, 10 nm, 20 nm, 25 nm, 30 nm and 40 nm, as long as it is within the above range.

[0054] It should be noted that, in this embodiment, by controlling the particle size, specific surface area and internal pore size of the nanoporous microspheres, the interior of the coating formed by the coating can contain more pores, and these pores are filled with air, and the thermal conductivity of air is extremely low. Therefore, nanoporous microspheres with high specific surface area and large internal pore size can significantly reduce the overall thermal conductivity of the coating and enhance the thermal insulation performance; secondly, more interfaces can be formed between the nanoporous microspheres with high specific surface area and the polymer matrix, and the thermal resistance at the interface is large, which further enhances the thermal insulation capacity of the coating.

[0055] In one embodiment of the present invention, the anti-rust pigment filler is an ion exchange anti-rust pigment filler; optionally, the anti-rust pigment filler includes at least one of aluminum tripolyphosphate, zinc phosphate, zinc aluminum phosphate, molybdate, and precipitated barium sulfate.

[0056] It should be noted that in this embodiment, by adding ion exchange type anti-rust pigment filler to the base material, the corrosion reaction on the surface of the metal substrate is suppressed by the ion exchange mechanism, and it can exchange with the corrosive ions (such as chloride ions and hydrogen ions) on the surface of the metal substrate and release ions with protective effects, such as Zn2+, Ca 2 +, Mg2+, etc. These ions can form a passivation film on the metal surface, thereby preventing or slowing down the corrosion process.

[0057] In one embodiment of the present invention, the coating further comprises an auxiliary agent, and the auxiliary agent comprises the following components in parts by weight: defoamer: 0.1-1 part; anti-settling agent: 0.1-1 part; diluent: 0.1-10 parts. Optionally, the defoamer can be a mineral oil defoamer, a silicone defoamer, or a modified organosiloxane defoamer. Optionally, the anti-settling agent can be hydroxyethyl cellulose, hydroxypropyl methyl cellulose, or polyvinyl alcohol. Optionally, the diluent comprises at least one of ethanol, butanol, ethylene glycol ether, diglycidyl ether, and polyglycidyl ether.

[0058] The present invention also provides a method for preparing the coating, which comprises the following steps:

[0059] S10, mixing and dispersing the aqueous acrylic copolymer emulsion, the diluent and water to obtain component A;

[0060] S20, mixing and dispersing the remaining raw materials and adding them to the component A obtained in step S10, stirring, dispersing and standing to obtain a coating.

[0061] The invention also proposes the application of the coating in the anti-corrosion and heat preservation of coal powder pipelines in coastal power plants.

[0062] It should be noted that the thermal conductivity of the coating of the present invention is relatively low, only 0.045-0.050 W / (m·K), and can be applied to the surface of equipment or pipelines below 180°C, and can reduce the temperature of the outer surface of equipment or pipelines at 120°C to 55-60°C, greatly reducing the heat dissipation loss of the equipment. Moreover, the coating of the present invention can form a dense coating due to the addition of stable nano-scale fillers, which can prevent the equipment from being corroded by external acids, alkalis, salts and water vapor for a long time, thereby avoiding the occurrence of corrosion under the insulation layer.

[0063] The present invention is further described below by means of specific embodiments:

[0064] The sources of the raw materials in the embodiments of the present invention are all commercially available, as follows; the present invention does not impose any particular limitation on the sources of the raw materials.

[0065] Example 1

[0066] The coating in Example 1 includes the following raw materials in parts by weight:

[0067] Aqueous acrylic copolymer emulsion: 25 parts; Nanoporous microspheres: 30 parts; Nanofunctional filler: 2 parts; Anti-rust color filler: 10 parts; Rust converter: 3 parts; Water: 30 parts; Defoamer: 0.5 parts; Anti-settling agent: 0.1 parts; Diluent: 5 parts.

[0068] The product model of the water-based acrylic copolymer emulsion used in Example 1 is Wantipro0622, purchased from Wanhua Chemical, which is a nano-scale emulsion and an anionic acrylic emulsion used for metal anti-corrosion coatings.

[0069] The nanoporous microspheres used in Example 1 are nanosilica microspheres with an average particle size of about 600 nm and a specific surface area of ​​about 600 m 2 / g, and the average internal pore size of the nanoporous microspheres is about 30nm.

[0070] The nano-functional filler used in Example 1 includes acidified multi-walled carbon nanotubes and hydroxylated barium titanate in a weight ratio of 3:1. The acidified multi-walled carbon nanotubes include 60wt% of acidified multi-walled carbon nanotubes with a length of less than 10μm, 20wt% of acidified multi-walled carbon nanotubes with a length of 10μm to 30μm, and 20wt% of acidified multi-walled carbon nanotubes with a length of 30μm to 100μm. The hydroxylated barium titanate includes 30wt% of hydroxylated barium titanate with a particle size of 0.2 to 0.5μm, 50wt% of hydroxylated barium titanate with a particle size of 0.5 to 1μm, and 20wt% of hydroxylated barium titanate with a particle size of 1 to 100μm.

[0071] Among them, the anti-rust color filler used in Example 1 is aluminum tripolyphosphate, the rust conversion agent used in Example 1 is G-450 rust conversion agent, the defoaming agent is AFE-1410 silicone defoaming agent, the anti-settling agent is hydroxyethyl cellulose, and the diluent is ethylene glycol ether.

[0072] The preparation method of the coating in Example 1 comprises the following steps:

[0073] S10, mixing and dispersing the aqueous acrylic copolymer emulsion, the diluent and water to obtain component A;

[0074] S20, mixing and dispersing the remaining raw materials and adding them to the component A obtained in step S10, stirring, dispersing and standing to obtain a coating.

[0075] Example 2

[0076] The coating of Example 2 includes the following raw materials in parts by weight:

[0077] Aqueous acrylic copolymer emulsion: 20 parts; Nano porous microspheres: 30 parts; Nano functional filler: 2 parts; Anti-rust color filler: 10 parts; Rust conversion agent: 3 parts; Water: 35 parts; Defoamer: 0.5 parts; Anti-settling agent: 0.1 parts; Diluent: 5 parts.

[0078] The aqueous acrylic copolymer emulsion, nanoporous microspheres, nanofunctional fillers, anti-rust pigment fillers, rust conversion agents, defoamers, anti-settling agents and diluents used in Example 2 are the same as those in Example 1.

[0079] Example 3

[0080] The coating of Example 3 includes the following raw materials in parts by weight:

[0081] Aqueous acrylic copolymer emulsion: 30 parts; Nano porous microspheres: 40 parts; Nano functional filler: 3 parts; Anti-rust color filler: 20 parts; Rust conversion agent: 0.5 parts; Water: 40 parts; Defoamer: 0.5 parts; Anti-settling agent: 0.1 parts; Diluent: 5 parts.

[0082] The product model of the aqueous acrylic copolymer emulsion used in Example 2 is 8223, purchased from Wanhua Chemical, is a nano-scale emulsion, an anionic styrene acrylic emulsion, mainly used as a primer to reinforce loose substrates.

[0083] The nanoporous microspheres, nanofunctional fillers, anti-rust pigment fillers, rust conversion agents, defoamers, anti-settling agents and diluents used in Example 3 are the same as those in Example 1.

[0084] Example 4

[0085] The coating of Example 4 includes the following raw materials in parts by weight:

[0086] Aqueous acrylic copolymer emulsion: 5 parts; Nano porous microspheres: 10 parts; Nano functional filler: 0.5 parts; Anti-rust color filler: 5 parts; Rust converter: 1 part; Water: 20 parts; Defoamer: 0.5 parts; Anti-settling agent: 0.1 parts; Diluent: 5 parts.

[0087] Among them, the aqueous acrylic copolymer emulsion, nanoporous microspheres, nanofunctional fillers, anti-rust pigment fillers, rust conversion agents, defoamers, anti-settling agents and diluents used in Example 4 are the same as those in Example 3.

[0088] Example 5

[0089] Example 5 is based on Example 1, except that the nano-functional filler in Example 5 includes acidified multi-walled carbon nanotubes and hydroxylated barium titanate in a weight ratio of 3:1; wherein the length of the acidified multi-walled carbon nanotubes is all within the range of 10 to 30 μm, and the particle size of the hydroxylated barium titanate is all within the range of 0.5 to 1 μm.

[0090] Comparative Example 1

[0091] Comparative Example 1 is based on Example 1, except that the coating in Comparative Example 1 does not contain nano-functional fillers.

[0092] Performance Testing

[0093] (1) The adhesion (MPa) of the coatings prepared in Examples 1 to 5 and Comparative Example 1 was measured with reference to standard GB / T 5210-2006 (pull-off method).

[0094] (2) The corrosion resistance of the coatings prepared in Examples 1 to 5 and Comparative Example 1 was determined with reference to standard GB / T 10125-2012.

[0095] (3) The water resistance of the coatings prepared in Examples 1 to 5 and Comparative Example 1 was determined with reference to Standard GB / T 1733-1993.

[0096] (4) The aging resistance of the coatings prepared in Examples 1 to 5 and Comparative Example 1 was determined with reference to the standard GB / T 1865-2009.

[0097] The above performance test results are shown in Table 1.

[0098] Table 1

[0099]

[0100] By analyzing the data in Table 1, it can be obtained that the coatings prepared in Examples 1 to 5 of the present invention are different from traditional water-based coatings with low cross-linking density and weak corrosion resistance. They have high cross-linking density, strong adhesion, high construction efficiency, and short coating time, and can be applied to the surfaces of special-shaped equipment to which traditional anti-corrosion and thermal insulation materials are difficult to apply; at the same time, the coatings prepared in Examples 1 to 5 of the present invention have good water resistance, corrosion resistance, and aging resistance.

[0101] In addition, the density of the coatings prepared in Examples 1 to 5 is between 0.76 and 0.87 g / cm 3 , coating on equipment or pipelines does not basically increase their load.

[0102] The thermal conductivity test shows that the thermal conductivity of the coatings prepared in Examples 1 to 5 is low, only 0.045 to 0.05 W / (m·K), while the thermal conductivity of the coating prepared in Comparative Example 1 reaches 0.32 to 0.36 W / (m·K).

[0103] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification under the technical concept of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A coating, characterized in that: The coating comprises the following raw materials in parts by weight: Water-based acrylic copolymer emulsion: 5-30 parts; Nanoporous microspheres: 10-40 parts; Nano functional filler: 0.5-3 parts; Anti-rust pigment filler: 5-20 parts; Rust converter: 0.5-3 parts; Water: 20-40 parts; Wherein, the nano-functional filler comprises at least one of acidified multi-walled carbon nanotubes and hydroxylated barium titanate.

2. The coating according to claim 1, characterized in that The acidified multi-walled carbon nanotubes include at least one of acidified multi-walled carbon nanotubes with a length of less than 10 μm, acidified multi-walled carbon nanotubes with a length of 10 to 30 μm, and acidified multi-walled carbon nanotubes with a length of 30 to 100 μm.

3. The coating according to claim 1, characterized in that The barium titanate hydroxylate includes at least one of barium titanate hydroxylate with a particle size of 0.2 to 0.5 μm, barium titanate hydroxylate with a particle size of 0.5 to 1 μm, and barium titanate hydroxylate with a particle size of 1 to 100 μm.

4. The coating according to claim 1, characterized in that The aqueous acrylic copolymer emulsion includes at least one of pure acrylic emulsion, styrene acrylic emulsion and silicone acrylic emulsion.

5. The coating according to claim 1, characterized in that The nanoporous microspheres include at least one of nano titanium dioxide microspheres, nano silicon dioxide microspheres, nano calcium carbonate microspheres and nano titanium dioxide / silicon dioxide microspheres.

6. The coating according to claim 1, characterized in that The average particle size of the nanoporous microspheres is 500 to 2000 nm; And / or, the specific surface area of ​​the nanoporous microspheres is 300 to 800 m 2 / g; And / or, the average internal pore diameter of the nanoporous microspheres is 5 to 40 nm.

7. The coating according to claim 1, characterized in that The anti-rust pigment filler is an ion exchange anti-rust pigment filler; The anti-rust pigment filler includes at least one of aluminum tripolyphosphate, zinc phosphate, zinc aluminum phosphate, molybdate, and barium sulfate.

8. The coating according to claim 1, characterized in that The coating also includes an auxiliary agent, which includes the following components in parts by weight: Defoaming agent: 0.1-1 part; Anti-settling agent: 0.1-1 part; Diluent: 0.1 to 10 parts.

9. A method for preparing the coating according to any one of claims 1 to 8, characterized in that: The preparation method of the coating comprises the following steps: S10, mixing and dispersing the aqueous acrylic copolymer emulsion, the diluent and water to obtain component A; S20, mixing and dispersing the remaining raw materials and adding them to the component A obtained in step S10, stirring, dispersing and standing to obtain a coating.

10. Use of the coating according to any one of claims 1 to 8 in the corrosion protection and thermal insulation of coal pulverized pipes in coastal power plants.

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