Anti-corrosion thermal insulation coating and preparation method thereof

Abstract

The invention relates to the technical field of coatings, and discloses an anti-corrosion thermal insulation coating and a preparation method thereof.The anti-corrosion thermal insulation coating is formed by mixing epoxy resin serving as a film forming substance and modified inorganic mineral additives, hollow glass beads and the like serving as auxiliary materials. Wherein the modified inorganic mineral additive is prepared by modifying a polymer macromolecular substance on the surface of sepiolite, and the polymer macromolecular substance can participate in the subsequent curing process of the epoxy acrylic resin, so that mutual winding and crosslinking with the epoxy acrylic resin are realized, the structural compactness of the coating is improved, and meanwhile, the coating has a good application prospect. The sepiolite is promoted to be uniformly dispersed in the coating, the permeation path of a corrosive medium is prolonged by utilizing the self-layer chain structure of the sepiolite, so that the anti-corrosion effect of the coating is enhanced, and the sepiolite and the modified inorganic mineral additive can also synergistically enhance the impact resistance of the coating.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and particularly relates to an anti-corrosion and heat-insulating coating and a preparation method thereof. Background Art

[0002] In the industrial and construction fields, the anti-corrosion and heat-insulating properties of materials are crucial, directly affecting the service life, energy consumption, and safety of equipment. At present, most coatings use polymer resins as film-forming substances, such as epoxy resins, acrylic resins, polyurethanes, etc. Among them, the epoxy resin molecular structure is rich in polar groups such as hydroxyl and ether bonds, which can have a strong adhesion force with substrates such as metals, enabling the coating to closely adhere to the substrate surface and form a dense protective film. Taking the common bisphenol A epoxy resin as an example, after reacting with a curing agent, it will form a three-dimensional network structure, which has a very high density and can effectively prevent the penetration of corrosion media such as water vapor, oxygen, and electrolyte ions, so it can exhibit certain anti-corrosion properties.

[0003] However, in special use environments such as the ocean, the anti-corrosion performance of epoxy resins is difficult to meet the requirements. Moreover, traditional epoxy resins do not have heat-insulating properties. Therefore, it is of great significance to improve the anti-corrosion and heat-insulating properties of epoxy resin coatings for their further application. Summary of the Invention

[0004] (I) Technical Problems to be Solved Aiming at the deficiencies of the prior art, the present invention provides an anti-corrosion and heat-insulating coating and a preparation method thereof.

[0005] (II) Technical Solutions An anti-corrosion and heat-insulating coating, comprising the following raw materials in parts by weight: 80-95 parts of epoxy acrylate resin, 2-5.5 parts of modified inorganic mineral additive, 5-10 parts of hollow glass microspheres, 3-5 parts of film-forming aid, 0.5-1.5 parts of defoamer, 0.5-1.5 parts of leveling agent, 1-3 parts of dispersant, 1-2 parts of wetting agent, 10-20 parts of curing agent; The modified inorganic mineral additive is sepiolite surface-modified with polymer macromolecular substances.

[0006] As a further solution of the present invention, the preparation method of the modified inorganic mineral additive comprises the following steps: Step 1: Add a silane coupling agent to deionized water, stir evenly, then raise the temperature to 50-60 °C, stir and hydrolyze for 3-6 h to form a modification solution; disperse sepiolite in anhydrous ethanol to form a dispersion, then add the modification solution to the dispersion, stir evenly, then raise the temperature to 70-80 °C, keep warm for 6-9 h, then cool and discharge, and separate the solid material to obtain modified sepiolite; Step 2: Add the modified sepiolite into N,N-dimethylformamide, and ultrasonically disperse it to form a uniform dispersion. Protect it by introducing nitrogen. Then, add an extender and a catalyst to the dispersion. After adding, raise the temperature to 70 - 80 °C, keep stirring for 2 - 4 h, then add 9,9-bis[4-(2,3-epoxypropoxyethoxy)phenyl]fluorene to the dispersion, and raise the temperature to 100 - 110 °C. Keep the temperature for 12 - 24 h, then cool down and discharge to obtain the modified inorganic mineral additive.

[0007] As a further aspect of the present invention, in Step 1, the silane coupling agent is 3-glycidoxypropyltrimethoxysilane or 3-glycidoxypropyltriethoxysilane.

[0008] As a further aspect of the present invention, in Step 2, the preparation method of the extender is as follows: Add decamethyl dihydropentasiloxane into absolute ethanol, stir and mix evenly. Then, add an acidifying reagent. After adding, raise the temperature to 70 - 75 °C, and continue to add a platinum catalyst under stirring conditions. After adding, keep stirring for 3 - 6 h, evaporate to remove the solvent, cool down and discharge, and collect the product to obtain the extender.

[0009] As a further aspect of the present invention, the molar ratio of the decamethyl dihydropentasiloxane to the acidifying reagent is 1:2.

[0010] As a further aspect of the present invention, the acidifying reagent is acrylic acid or methacrylic acid.

[0011] As a further aspect of the present invention, in Step 2, the catalyst is any one of tetrabutylammonium bromide, tetramethylammonium bromide, tetrabutylammonium hydrogensulfate, and tetrabutylammonium chloride.

[0012] As a further aspect of the present invention, in Step 2, the mass ratio of the modified sepiolite, the extender, and 9,9-bis[4-(2,3-epoxypropoxyethoxy)phenyl]fluorene is 1:3.5 - 6:2 - 4.

[0013] In the above technical solution, first, sepiolite is surface-modified with a silane coupling agent to make the surface of sepiolite carry epoxy functional groups, and modified sepiolite is prepared. Then, under the action of a catalyst, the extender realizes the connection effect of 9,9-bis[4-(2,3-epoxypropoxyethoxy)phenyl]fluorene and sepiolite through the active carboxyl substituents at both ends of the structure. The unreacted 9,9-bis[4-(2,3-epoxypropoxyethoxy)phenyl]fluorene and extender in the system can carry out continuous ring-opening esterification polymerization reactions through the active functional groups at the ends of their respective structures, so as to form an in-situ polymerization effect of 9,9-bis[4-(2,3-epoxypropoxyethoxy)phenyl]fluorene and extender on the surface of sepiolite with the epoxy groups on the sepiolite surface as the active initiation sites, thereby preparing a polymer macromolecular substance with a fluorene-siloxane block structure on the surface and obtaining a modified inorganic mineral additive.

[0014] The extender is prepared by a hydrosilylation reaction of Si-H and unsaturated alkenyl functional groups in their respective structures under the action of a platinum catalyst, using decamethyl-dihydro-pentasiloxane and an acidifying reagent as reactants. By controlling the molar ratio of the two, the extender can be made to have active carboxyl substituents at both ends of its structure.

[0015] As a further solution of the present invention, the film-forming aid is at least one of propylene glycol monobutyl ether, dipropylene glycol monobutyl ether, or ethylene glycol monobutyl ether acetate; the defoamer is NYK-065; the leveling agent is BYK-310 or BYK-315N; the dispersant is triethanolamine; the wetting agent is alkyl polyoxyethylene ether; the curing agent is a diamine curing agent.

[0016] A preparation method of an anti-corrosion and heat-insulating coating comprises the following steps: First step: Weigh each raw material according to the weight parts and set aside. Second step: Add epoxy acrylate resin, modified inorganic mineral additive, hollow glass microspheres, film-forming aid, leveling agent, dispersant, and wetting agent into a stirring kettle, and mechanically stir and mix at a stirring rate of 500-1000 r / min for 20-30 min at room temperature to form a premixed material. Third step: Add a curing agent to the premixed material, stir for 10-20 min, then add a defoamer, adjust the stirring rate to 200-300 r / min, continue to stir for 20-30 min, then stop stirring, let it stand for 1-2 h, and discharge to obtain the product.

[0017] (III) Beneficial technical effects The present invention prepares a modified inorganic mineral additive by modifying the surface of sepiolite with polymer macromolecular substances. First, the polymer macromolecular substances contain a large number of hydroxyl functional groups generated by ring-opening reactions, which can participate in the subsequent curing process of epoxy acrylate resin, thereby achieving mutual entanglement and cross-linking with epoxy acrylate resin. On the one hand, this increases the molecular chain density of epoxy acrylate resin, and thus also increases the density of the cured coating structure, effectively preventing the penetration of corrosive media. This cross-linked structure enables sepiolite to exist in the coating structure in the form of a cross-linking core, greatly improving the interfacial compatibility between sepiolite and epoxy acrylate resin, promoting the uniform dispersion of sepiolite in the coating, and then utilizing the self-layered chain structure of sepiolite to extend the penetration path of corrosive media, thereby further enhancing the anti-corrosion effect of the coating. At the same time, the uniformly dispersed sepiolite can also produce an obvious strengthening effect and improve the impact performance of the coating. On the other hand, the polymer macromolecular substances also contain a fluorene-siloxane block structure, where the rigid fluorene ring can improve the stability of the coating and further enhance the anti-impact performance of the coating. The presence of the siloxane chain segment can make the surface of the coating extremely hydrophobic, preventing corrosive media from adhering to the coating surface for a long time and causing corrosion due to continuous penetration.

[0018] The present invention improves the heat preservation effect of the coating by adding hollow glass microspheres and forming air cavities in the coating to reduce the heat conduction path. Detailed implementation mode

[0019] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below. Preferred embodiments of the present invention are given below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure content of the present invention more thorough and comprehensive.

[0020] Example 1

[0021] An anti-corrosion and heat-insulating coating, comprising the following raw materials in parts by weight: 80 parts of epoxy acrylate resin, 2 parts of modified inorganic mineral additive, 5 parts of hollow glass microspheres, 3 parts of film-forming auxiliary propylene glycol monobutyl ether, 0.5 part of defoamer NYK-065, 0.5 part of leveling agent BYK-310, 1 part of dispersant triethanolamine, 1 part of wetting agent alkyl polyoxyethylene ether, and 10 parts of curing agent polyetheramine; The preparation method of the anti-corrosion and heat-insulating coating comprises the following steps: First step, weigh each raw material according to the parts by weight and set aside; Step 2: Add epoxy acrylate resin, modified inorganic mineral additive, hollow glass microspheres, film-forming auxiliary propylene glycol butyl ether, leveling agent BYK-310, dispersant triethanolamine, and wetting agent alkyl polyoxyethylene ether into a stirring kettle. Under room temperature conditions, mechanically stir and mix at a stirring rate of 500 r / min for 30 min to form a premixed material; Step 3: Add curing agent polyetheramine to the premixed material, stir for 10 min, then add defoaming agent NYK-065, adjust the stirring rate to 200 r / min, continue to stir for 30 min, then stop stirring, let it stand for 1 h, and discharge the material, then it is ready.

[0022] Example 2

[0023] An anti-corrosion and heat-insulating coating, comprising the following raw materials by weight parts: 85 parts of epoxy acrylate resin, 5 parts of modified inorganic mineral additive, 6 parts of hollow glass microspheres, 4 parts of film-forming auxiliary dipropylene glycol monobutyl ether, 1 part of defoaming agent NYK-065, 1 part of leveling agent BYK-315N, 2 parts of dispersant triethanolamine, 1.5 parts of wetting agent alkyl polyoxyethylene ether, 15 parts of curing agent polyetheramine; The preparation method of the anti-corrosion and heat-insulating coating comprises the following steps: Step 1: Weigh each raw material according to the weight parts and set aside; Step 2: Add epoxy acrylate resin, modified inorganic mineral additive, hollow glass microspheres, film-forming auxiliary propylene glycol monobutyl ether, leveling agent BYK-315N, dispersant triethanolamine, and wetting agent alkyl polyoxyethylene ether into a stirring kettle. Under room temperature conditions, mechanically stir and mix at a stirring rate of 800 r / min for 25 min to form a premixed material; Step 3: Add curing agent polyetheramine to the premixed material, stir for 15 min, then add defoaming agent NYK-065, adjust the stirring rate to 300 r / min, continue to stir for 25 min, then stop stirring, let it stand for 1 h, and discharge the material, then it is ready.

[0024] Example 3

[0025] An anti-corrosion and heat-insulating coating, comprising the following raw materials by weight parts: 95 parts of epoxy acrylate resin, 5.5 parts of modified inorganic mineral additive, 10 parts of hollow glass microspheres, 5 parts of film-forming auxiliary dipropylene glycol monobutyl ether, 1.5 parts of defoaming agent NYK-065, 1.5 parts of leveling agent BYK-315N, 3 parts of dispersant triethanolamine, 2 parts of wetting agent alkyl polyoxyethylene ether, 20 parts of curing agent polyetheramine; The preparation method of the anti-corrosion and heat-insulating coating comprises the following steps: Step 1: Weigh each raw material according to the weight parts and set aside; Step 2: Add epoxy acrylate resin, modified inorganic mineral additive, hollow glass microspheres, film-forming aid ethylene glycol monobutyl acetate, leveling agent BYK-315N, dispersant triethanolamine, and wetting agent alkyl polyoxyethylene ether into a stirring kettle. Under room temperature conditions, mechanically stir and mix at a stirring rate of 1000 r / min for 20 min to form a premixed material; Step 3: Add curing agent polyetheramine into the premixed material, stir for 20 min, then add defoaming agent NYK-065, adjust the stirring rate to 300 r / min, continue stirring for 20 min, then stop stirring, let stand for 2 h, and discharge the material to obtain the product.

[0026] The modified inorganic mineral additive in the above examples is prepared by the following method: Step 1: Add 1.2 g of 3-glycidoxypropyltriethoxysilane into 50 mL of deionized water, stir evenly, then raise the temperature to 55 °C and stir for hydrolysis for 4 h to form a modified solution; Disperse 1.5 g of sepiolite in 60 mL of absolute ethanol to form a dispersion liquid, then add the modified solution into the dispersion liquid, stir evenly, then raise the temperature to 75 °C, keep warm for 8 h, then cool down and discharge the material, and separate out the solid material to obtain modified sepiolite; Step 2: Add 1 g of modified sepiolite into N,N-dimethylformamide, ultrasonically disperse it to form a homogeneous dispersion liquid, introduce nitrogen protection, then add 5.5 g of extender and tetrabutylammonium bromide into the dispersion liquid. After adding, raise the temperature to 75 °C, keep warm and stir for 3 h, then add 3 g of 9,9-bis[4-(2,3-epoxypropoxyethoxy)phenyl]fluorene into the dispersion liquid, and raise the temperature to 110 °C, keep warm continuously for 16 h, then cool down and discharge the material to obtain the modified inorganic mineral additive.

[0027] The preparation method of the extender is as follows: Add 0.2 g of decamethyl-dihydro-pentasiloxane into absolute ethanol, stir and mix evenly, then add 0.1 g of methacrylic acid. After adding, raise the temperature to 70 °C, and continue to add 0.01 g of platinum catalyst under stirring conditions. After adding, keep warm and stir for 4 h, evaporate and remove the solvent, cool down and discharge the material, and collect the product to obtain the extender.

[0028] Comparative Example 1 An anti-corrosion and heat-insulating coating, comprising the following raw materials in parts by weight: 85 parts of epoxy acrylate resin, 5 parts of sepiolite, 6 parts of hollow glass microspheres, 4 parts of film-forming aid dipropylene glycol monobutyl ether, 1 part of defoaming agent NYK-065, 1 part of leveling agent BYK-315N, 2 parts of dispersant triethanolamine, 1.5 parts of wetting agent alkyl polyoxyethylene ether, 15 parts of curing agent polyetheramine; The preparation method of the anti-corrosion and heat-insulating coating comprises the following steps: Step 1: Weigh each raw material according to the parts by weight and set aside. Step 2: Add epoxy acrylate resin, sepiolite, hollow glass microspheres, film-forming auxiliary propylene glycol monobutyl ether, leveling agent BYK-315N, dispersant triethanolamine, and wetting agent alkyl polyoxyethylene ether into a stirring kettle. Under room temperature conditions, mechanically stir and mix at a stirring rate of 800 r / min for 25 min to form a premixed material. Step 3: Add curing agent polyetheramine to the premixed material, stir for 15 min, then add defoaming agent NYK-065, adjust the stirring rate to 300 r / min, continue stirring for 25 min, then stop stirring, let it stand for 1 h, and discharge to obtain the product.

[0029] Comparative Example 2 An anti-corrosion and heat-insulating coating, comprising the following raw materials according to parts by weight: 85 parts of epoxy acrylate resin, 6 parts of hollow glass microspheres, 4 parts of film-forming auxiliary dipropylene glycol monobutyl ether, 1 part of defoaming agent NYK-065, 1 part of leveling agent BYK-315N, 2 parts of dispersant triethanolamine, 1.5 parts of wetting agent alkyl polyoxyethylene ether, and 15 parts of curing agent polyetheramine. The preparation method of the anti-corrosion and heat-insulating coating comprises the following steps: Step 1: Weigh each raw material according to the parts by weight and set aside. Step 2: Add epoxy acrylate resin, hollow glass microspheres, film-forming auxiliary propylene glycol monobutyl ether, leveling agent BYK-315N, dispersant triethanolamine, and wetting agent alkyl polyoxyethylene ether into a stirring kettle. Under room temperature conditions, mechanically stir and mix at a stirring rate of 800 r / min for 25 min to form a premixed material. Step 3: Add curing agent polyetheramine to the premixed material, stir for 15 min, then add defoaming agent NYK-065, adjust the stirring rate to 300 r / min, continue stirring for 25 min, then stop stirring, let it stand for 1 h, and discharge to obtain the product.

[0030] Performance Test Make the coating in the examples and comparative examples into coating test samples, conduct various performance tests, and record the results in Table 1: Table 1

[0031] The method for the corrosion resistance test is as follows: Immerse the sample in a sodium chloride solution with a mass concentration of 3.5%, observe the coating phenomenon after one week, and evaluate the corrosion resistance of the coating.

[0032] The test method for impact resistance refers to the standard GB / T 10295-2008.

[0033] The reference standard for the thermal conductivity test method is GB / T 1732-2020.

[0034] According to the test results, it can be seen that the cured coating of the paint added with the modified inorganic mineral additive shows more excellent impact resistance and corrosion resistance.

[0035] After replacing the modified inorganic mineral additive with unmodified sepiolite, it cannot be well compatible with epoxy resin to achieve a uniform dispersion effect, nor can it utilize the advantages of polymer macromolecular substances, resulting in a significant decline in mechanical properties and corrosion resistance.

[0036] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0037] Enlightened by the ideal embodiments of the present invention, through the above description, relevant personnel can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

Claims

1. An anti-corrosion and heat-insulating coating, characterized in that It includes the following raw materials by weight parts: 80-95 parts of epoxy acrylate resin, 2-5.5 parts of modified inorganic mineral additive, 5-10 parts of hollow glass microspheres, 3-5 parts of film-forming aid, 0.5-1.5 parts of defoamer, 0.5-1.5 parts of leveling agent, 1-3 parts of dispersant, 1-2 parts of wetting agent, and 10-20 parts of curing agent; The modified inorganic mineral additive is sepiolite surface-modified with polymer macromolecular substances.

2. The anti-corrosion and heat-insulating coating according to claim 1, wherein The preparation method of the modified inorganic mineral additive includes the following steps: Step 1: Add a silane coupling agent to deionized water, stir evenly, then raise the temperature to 50-60 °C, stir and hydrolyze for 3-6 h to form a modification solution; disperse sepiolite in absolute ethanol to form a dispersion, then add the modification solution to the dispersion, stir evenly, then raise the temperature to 70-80 °C, keep warm for 6-9 h, then cool down and discharge, separate the solid material to obtain modified sepiolite; Step 2: Add the modified sepiolite to N,N-dimethylformamide, ultrasonically disperse to form a uniform dispersion, pass in nitrogen for protection, then add an extender and a catalyst to the dispersion. After adding, raise the temperature to 70-80 °C, keep warm and stir for 2-4 h, then add 9,9-bis[4-(2,3-epoxypropoxyethoxy)phenyl]fluorene to the dispersion, and raise the temperature to 100-110 °C, continuously keep warm for 12-24 h, then cool down and discharge to obtain the modified inorganic mineral additive.

3. The anti-corrosion and heat-insulating coating according to claim 2, wherein In Step 1, the silane coupling agent is 3-glycidoxypropyltrimethoxysilane or 3-glycidoxypropyltriethoxysilane.

4. The anti-corrosion and heat-insulating coating according to claim 2, wherein In Step 2, the preparation method of the extender is as follows: Add decamethyl-dihydro-pentasiloxane to absolute ethanol, stir and mix evenly, then add an acidifying reagent. After adding, raise the temperature to 70-75 °C, and continue to add a platinum catalyst under stirring conditions. After adding, keep warm and stir for 3-6 h, evaporate to remove the solvent, cool down and discharge, collect the product to obtain the extender.

5. The anti-corrosion and heat-insulating coating according to claim 4, characterized in that, The molar ratio of the decamethyl-dihydro-pentasiloxane to the acidifying reagent is 1:

2.

6. The anti-corrosion and heat-insulating coating according to claim 4, characterized in that, The acidifying reagent is acrylic acid or methacrylic acid.

7. The anti-corrosion and heat-insulating coating according to claim 2, characterized in that In Step 2, the catalyst is any one of tetrabutylammonium bromide, tetramethylammonium bromide, tetrabutylammonium hydrogensulfate, and tetrabutylammonium chloride.

8. The anti-corrosion and heat-insulating coating according to claim 2, characterized in that, In Step 2, the mass ratio of the modified sepiolite, the extender, and 9,9-bis[4-(2,3-epoxypropoxyethoxy)phenyl]fluorene is 1:3.5-6:2-4.

9. The anti-corrosion and heat-insulating coating according to claim 1, wherein The film-forming aid is at least one of propylene glycol butyl ether, dipropylene glycol monobutyl ether, or ethylene glycol butyl ether acetate; the defoamer is NYK-065; the leveling agent is BYK-310 or BYK-315N; the dispersant is triethanolamine; the wetting agent is alkyl polyoxyethylene ether; the curing agent is a diamine curing agent.

10. A method for preparing the anti-corrosion and heat-insulating coating according to claim 1, characterized in that, It includes the following steps: The first step: Weigh each raw material according to the weight parts and set aside; Step 2: Add epoxy acrylate resin, modified inorganic mineral additive, hollow glass microspheres, film-forming aid, leveling agent, dispersant and wetting agent into a stirring kettle, and mechanically stir and mix at a stirring rate of 500-1000 r / min for 20-30 min at room temperature to form a premix; Step 3: Add a curing agent to the premix, stir for 10-20 min, then add an antifoaming agent, adjust the stirring rate to 200-300 r / min, continue to stir for 20-30 min, then stop stirring, let stand for 1-2 h, and discharge to obtain the product.

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