Aspartic acid polyurea anticorrosive coating and method for preparing the same

Abstract

This invention belongs to the field of aspartic polyurea technology, specifically relating to aspartic polyurea anticorrosive coatings and their preparation methods. It is composed of component A and component B. Component A includes: polyaspartic ester resin: 35-45 parts; hydroxyl-terminated polybutadiene acrylonitrile: 5-10 parts; inorganic filler: 30-37 parts; color paste: 8-10 parts; additives: 2-3 parts; solvent: 5-10 parts. Component B includes: IPDI aliphatic isocyanate prepolymer: 5-10 parts; HDI trimer: 60-70 parts; solvent: 20-35 parts. Through the synergistic effect of polyaspartic ester resin and hydroxyl-terminated polybutadiene acrylonitrile, combined with the use of IPDI aliphatic isocyanate prepolymer, the coating possesses excellent toughness, minimal hardness change at low temperatures, impact resistance, and crack prevention. Simultaneously, it exhibits stronger resistance to pollution, impermeability, and high-concentration acid and alkali corrosion in harsh anticorrosive environments.

Description

Technical Field

[0001] This invention belongs to the field of aspartic polyurea technology, specifically relating to aspartic polyurea anticorrosive coatings and their preparation methods. Background Technology

[0002] Currently, commercially available aspartic polyurea anticorrosive coatings are mainly composed of aspartic resin, inert fillers, and isocyanate curing agents. While they can meet basic usage requirements in light and moderate corrosion environments, they still have significant shortcomings in heavy-duty corrosion protection. Although aspartic polyurea itself possesses advantages such as high strength and wear resistance, it suffers from insufficient low-temperature flexibility and poor stain resistance. For example, in heavy corrosion protection scenarios such as marine vessels and wind power generation, the paint film is prone to cracking when exposed to high-speed erosion from waves and sand, thus affecting its service life. In the petrochemical, pharmaceutical, and medical fields, the paint film is prone to contamination, corrosion peeling, and wrinkling when exposed to oil stains and high-concentration strong acid corrosion, affecting both appearance and service life.

[0003] Therefore, developing an aspartic polyurea anticorrosive coating that combines excellent low-temperature toughness, strong stain resistance, and acid and alkali corrosion resistance has become an urgent technical problem to be solved in the field of heavy-duty anticorrosive coating. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide an aspartic polyurea anticorrosive coating. Through the synergistic effect of polyaspartic ester resin and hydroxyl-terminated polybutadiene acrylonitrile, the coating possesses excellent toughness. The introduction of highly elastic IPDI aliphatic isocyanate prepolymer into the curing agent results in a final material with minimal hardness change at low temperatures, impact resistance, and crack prevention. Simultaneously, it exhibits stronger resistance to pollution, impermeability, and high-concentration acid and alkali corrosion in harsh anticorrosive environments.

[0005] Another object of the present invention is to provide a method for preparing an aspartic polyurea anticorrosive coating.

[0006] The technical solution adopted in this invention is as follows: The aspartic polyurea anticorrosive coating is made of component A and component B in a mass ratio of (2-3):1, wherein, Component A comprises the following raw materials in parts by weight: Polyaspartic acid ester resin: 35-45 parts; Hydroxyl-terminated polybutadiene acrylonitrile: 5-10 parts; Inorganic filler: 30-37 parts; Color paste: 8-10 parts; Additives: 2-3 parts; Solvent; 5-10 parts; Component B comprises the following raw materials in parts by weight: 5-10 parts of IPDI aliphatic isocyanate prepolymer; HDI trimer: 60-70 parts; Solvent: 20-35 parts; The additives are a mixture of dispersants, defoamers, light stabilizers, ultraviolet absorbers, leveling agents, anti-settling agents, and silane coupling agents.

[0007] The polyaspartic acid ester resin mentioned is Desmophen ® NH 1420 was purchased from Covestro AG, Germany.

[0008] The hydroxyl-terminated polybutadiene acrylonitrile (HTBN) was purchased from Zibo Qilong Chemical Co., Ltd.

[0009] The inorganic filler is a mixture of zinc phosphate, mica powder and precipitated barium sulfate, with a mass ratio of (10-14):(10-13):10, and the particle size of all of them is 1250 mesh.

[0010] The pigment is an oil-based pigment, purchased from Mingguang Codina Microelectronics Co., Ltd.

[0011] The solvent is one or more of butyl acetate or propylene glycol methyl ether acetate.

[0012] The IPDI aliphatic isocyanate prepolymer is WANNATE. ® IT-2100 was purchased from Wanhua Chemical Group Co., Ltd.

[0013] The HDI trimer is WANNATE. ® HT-100 was purchased from Wanhua Chemical Group Co., Ltd.

[0014] The dispersant was Disuper S4, purchased from Guangdong Core New Materials Co., Ltd.; the defoamer was Defom6800, purchased from Deqian (Shanghai) Chemical Co., Ltd.

[0015] The light stabilizer is UNIQLIGHT 992, purchased from UNIQLIGHT Chemicals (Shanghai) Co., Ltd.; the ultraviolet absorber is UNIQLIGHT 930, purchased from UNIQLIGHT Chemicals (Shanghai) Co., Ltd.

[0016] The leveling agent was DISPARLON L-1983N, purchased from Kusumoto Chemical Co., Ltd.; the anti-settling agent was BYK-410, purchased from BYK Chemicals, Germany; and the silane coupling agent was KH-560, purchased from Shandong Silicon Science New Materials Co., Ltd.

[0017] The preparation method of the aspartic polyurea anticorrosive coating includes the following steps: (1) Mix polyaspartic acid ester resin, hydroxyl-terminated polybutadiene acrylonitrile, inorganic filler, dispersant and defoamer, dehydrate under vacuum and cool to below 60°C, add color paste, light stabilizer, ultraviolet absorber, leveling agent, anti-settling agent and silane coupling agent and disperse evenly, finally add solvent and stir evenly to obtain component A. (2) Mix IPDI aliphatic isocyanate prepolymer, HDI trimer and solvent and stir until homogeneous to obtain component B; (3) When using, mix component A and component B, apply evenly to the substrate, and after curing, you will get aspartic polyurea anti-corrosion coating.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) This invention achieves a balance between the hardness and toughness of the coating by combining the synergistic effect of polyaspartic ester resin and HTBN, and by introducing highly elastic IPDI aliphatic isocyanate prepolymer into the curing agent. This meets the hardness requirements of the aspartic polyurea anticorrosive coating standard HG / T 5368-2018, and significantly improves the coating's impact resistance and crack prevention performance at low temperatures. (2) In this invention, the terminal hydroxyl groups of HTBN are chemically bonded to the isocyanate groups, so that the nitrile rubber soft segments of HTBN and the elastic skeleton of IPDI prepolymer are embedded together in the polyurea crosslinking network to form a composite structure of "rigid matrix - dual elastic segments". The nitrile segments of HTBN undergo microphase separation with the aspartic polyurea matrix, forming a uniformly dispersed island structure in situ, while the aliphatic skeleton of IPDI prepolymer provides stable crosslinking support for this structure. This not only retains the original weather resistance, corrosion resistance and high hardness of polyaspartic ester resin, but also gives the coating excellent toughness, which can prevent the coating from cracking and breaking due to stress or changes in ambient temperature, prevent corrosive media from penetrating and corroding the substrate, and extend the service life of the coating. In particular, it can still maintain good performance in low temperature environment, which solves the problem of insufficient flexibility and toughness of traditional aspartic polyurea anti-corrosion coatings at low temperatures. (3) The present invention uses HTBN to toughen polyaspartic acid ester resin, which can significantly reduce the internal stress of the coating and improve the adhesion and durability of the coating in special parts. At stress concentration points such as the edges and corners of the substrate, the coating is not easily peeled off from the substrate due to environmental temperature fluctuations or external interference, ensuring the stability of the anti-corrosion effect, avoiding the exposure of the substrate to corrosion due to local peeling of the coating, and further extending the overall service life of the substrate and the coating. It is suitable for the anti-corrosion needs of more complex shaped substrates; (4) This invention utilizes the excellent oil and solvent resistance of HTBN to synergistically enhance the material's protective ability against various chemical media with polyaspartic acid ester resin. The synergistic effect of HTBN and polyaspartic acid ester resin enables the coating to maintain excellent stain resistance and impermeability even in harsh anti-corrosion environments such as oil staining and high-concentration acid and alkali corrosion, effectively resisting chemical media erosion and avoiding problems such as coating contamination, peeling, and wrinkling. This broadens the application range of aspartic polyurea anti-corrosion coatings in heavy anti-corrosion fields such as chemical workshops, chemical storage tank areas, ships, and wind power generation, and improves its applicability and reliability under special working conditions. Detailed Implementation

[0019] The present invention will be further described below with reference to the embodiments, but these embodiments do not limit the implementation of the present invention.

[0020] Unless otherwise specified, the raw materials used in the examples and comparative examples are all commercially available materials, and the process methods used in the examples and comparative examples are all conventional methods in the art.

[0021] Example 1 The aspartic polyurea anticorrosive coating is made of component A and component B in a mass ratio of 2:1, wherein, Component A comprises the following raw materials in parts by weight: Desmophen ® NH 1420: 40 copies; Hydroxyl-terminated polybutadiene acrylonitrile: 10 parts; Precipitated barium sulfate: 10 parts; Mica powder: 10 parts; Zinc phosphate: 10 parts; Oil-based pigment: 10 parts; Additives: 3 parts; Butyl acetate: 7 parts; Component B comprises the following raw materials in parts by weight: WANNATE ® IT-2100: 5 copies; WANNATE ® HT-100: 60 servings; Butyl acetate: 20 parts; Propylene glycol methyl ether acetate: 15 parts; The additives are a mixture of 0.5 parts dispersant Disuper S4, 0.3 parts defoamer Defom 6800, 0.3 parts light stabilizer UNIQLIGHT 992, 0.3 parts ultraviolet absorber UNIQLIGHT 930, 0.5 parts leveling agent DISPARLON L-1983N, 0.1 parts anti-settling agent BYK-410 and 1 part silane coupling agent KH-560.

[0022] The preparation method of the aspartic polyurea anticorrosive coating includes the following steps: (1) Desmophen polyaspartic acid ester resin ® NH 1420, hydroxyl-terminated polybutadiene acrylonitrile, precipitated barium sulfate, mica powder, zinc phosphate, dispersant Disuper S4, and defoamer Defom 6800 were mixed and added to a high-speed disperser. The high-speed disperser was started, and the temperature was raised to 95°C at a speed of 1000 r / min. The mixture was then vacuum dehydrated and dispersed for 2 h. The temperature was then lowered to 60°C, and oily pigment, light stabilizer UNIQLIGHT 992, UV absorber UNIQLIGHT 930, leveling agent DISPARLON L-1983N, anti-settling agent BYK-410, and silane coupling agent KH-560 were added. The mixture was stirred and dispersed at a speed of 800 r / min for 20 min. Then, butyl acetate was added as solvent, and the mixture was stirred at a speed of 400 r / min for 5 min. After stirring until homogeneous, component A was obtained. (2) WANNATE ® IT-2100, WANNATE ® HT-100, butyl acetate and propylene glycol methyl ether acetate were mixed and added to a reaction vessel, stirred for 15 minutes until homogeneous, to obtain component B. (3) When using, mix component A and component B, apply evenly to the substrate, and cure at 25°C for 4 hours to obtain aspartic polyurea anti-corrosion coating.

[0023] Example 2 The aspartic polyurea anticorrosive coating is made of component A and component B in a mass ratio of 3:1, wherein, Component A comprises the following raw materials in parts by weight: Desmophen ® NH 1420: 35 copies; Hydroxyl-terminated polybutadiene acrylonitrile: 5 parts; Precipitated barium sulfate: 10 parts; Mica powder: 13 parts; Zinc phosphate: 14 parts; Oil-based pigment: 10 parts; Additives: 3 parts; Butyl acetate: 10 parts; Component B comprises the following raw materials in parts by weight: WANNATE ® IT-2100: 10 copies; WANNATE ® HT-100: 70 servings; Butyl acetate: 15 parts; Propylene glycol methyl ether acetate: 5 parts; The additives are a mixture of 0.5 parts dispersant Disuper S4, 0.3 parts defoamer Defom 6800, 0.3 parts light stabilizer UNIQLIGHT 992, 0.3 parts ultraviolet absorber UNIQLIGHT 930, 0.5 parts leveling agent DISPARLON L-1983N, 0.1 parts anti-settling agent BYK-410 and 1 part silane coupling agent KH-560.

[0024] The preparation method of the aspartic polyurea anticorrosive coating is the same as that in Example 1.

[0025] Example 3 The aspartic polyurea anticorrosive coating is made of component A and component B in a mass ratio of 2:1, wherein, Component A comprises the following raw materials in parts by weight: Desmophen ® NH 1420: 45 copies; Hydroxyl-terminated polybutadiene acrylonitrile: 8 parts; Precipitated barium sulfate: 10 parts; Mica powder: 10 parts; Zinc phosphate: 10 parts; Oil-based pigment: 10 parts; Additives: 2 parts; Butyl acetate: 5 parts; Component B comprises the following raw materials in parts by weight: WANNATE ® IT-2100: 8 copies; WANNATE ® HT-100: 65 copies; Butyl acetate: 17 parts; Propylene glycol methyl ether acetate: 10 parts; The additives are a mixture of 0.4 parts dispersant Disuper S4, 0.2 parts defoamer Defom 6800, 0.2 parts light stabilizer UNIQLIGHT 992, 0.2 parts ultraviolet absorber UNIQLIGHT 930, 0.3 parts leveling agent DISPARLON L-1983N, 0.2 parts anti-settling agent BYK-410 and 0.5 parts silane coupling agent KH-560.

[0026] The preparation method of the aspartic polyurea anticorrosive coating is the same as that in Example 1.

[0027] Comparative Example 1 The aspartic polyurea anticorrosive coating is made of component A and component B in a mass ratio of 2:1, wherein, Component A comprises the following raw materials in parts by weight: Desmophen ® NH 1420: 45 copies; Precipitated barium sulfate: 10 parts; Mica powder: 10 parts; Zinc phosphate: 18 parts; Oil-based pigment: 10 parts; Additives: 2 parts; Butyl acetate: 5 parts; Component B comprises the following raw materials in parts by weight: WANNATE ® IT-2100: 8 copies; WANNATE ® HT-100: 65 copies; Butyl acetate: 17 parts; Propylene glycol methyl ether acetate: 10 parts; Everything else is the same as in Example 3.

[0028] Comparative Example 2 The aspartic polyurea anticorrosive coating is made of component A and component B in a mass ratio of 2:1, wherein, Component A comprises the following raw materials in parts by weight: Desmophen ® NH 1420: 45 copies; Hydroxyl-terminated polybutadiene acrylonitrile: 8 parts; Precipitated barium sulfate: 10 parts; Mica powder: 10 parts; Zinc phosphate: 10 parts; Oil-based pigment: 10 parts; Additives: 2 parts; Butyl acetate: 5 parts; Component B comprises the following raw materials in parts by weight: WANNATE ® HT-100: 67 copies; Butyl acetate: 20 parts; Propylene glycol methyl ether acetate: 13 parts; Everything else is the same as in Example 3.

[0029] Referring to HG / T 5368-2018, the pencil hardness, impact resistance and artificial weathering resistance of the aspartic polyurea anticorrosive coatings prepared in Examples 1-3 and Comparative Examples 1-2 were tested, with the impact resistance test including a -10℃ test.

[0030] The aspartic polyurea anticorrosive materials prepared in Examples 1-3 and Comparative Examples 1-2 were subjected to acid and alkali resistance tests according to the chemical resistance test method in HG / T 5368-2018. The test conditions were adjusted as follows: Acid resistance: Tested using 30wt.% sulfuric acid solution for 168 hours; Alkali resistance: Tested using 30wt.% sodium hydroxide solution for 168 hours.

[0031] Add test: Oxidation resistance: Tested using 35wt.% hydrogen peroxide solution for 168 hours.

[0032] Stain resistance: Tested using 1% povidone-iodine solution for 72 hours.

[0033] The test results are shown in Table 1: Table 1 Performance Test Results

[0034] As shown in Table 1, the aspartic polyurea anticorrosive coatings prepared in Examples 1-3 exhibit excellent impact resistance in low-temperature environments due to the synergistic effect of polyaspartic ester resin and hydroxyl-terminated polybutadiene acrylonitrile, combined with the use of highly elastic IPDI aliphatic isocyanate prepolymer. The coating is not prone to cracking, effectively extending its service life. It also shows excellent performance in terms of chemical corrosion resistance and pollution resistance.

[0035] In Comparative Example 1, since hydroxyl-terminated polybutadiene acrylonitrile was not used, the resulting aspartic polyurea anticorrosive coating had high rigidity, insufficient toughness, and poor impact resistance. It showed excellent performance in acid and alkali corrosion resistance, but poor oxidation and stain resistance.

[0036] In Comparative Example 2, because IPDI aliphatic isocyanate prepolymer was not used, the final aspartic polyurea anticorrosive coating had a low soft segment content. Under low temperature conditions, the material's toughness decreased, its hardness increased, and its impact resistance decreased, making it prone to cracking and damage during use.

Claims

1. An aspartic polyurea anticorrosive coating, characterized in that, It is made from component A and component B in a mass ratio of (2-3):1, wherein, Component A comprises the following raw materials in parts by weight: Polyaspartic acid ester resin: 35-45 parts; Hydroxyl-terminated polybutadiene acrylonitrile: 5-10 parts; Inorganic filler: 30-37 parts; Color paste: 8-10 parts; Additives: 2-3 parts; Solvent; 5-10 parts; Component B comprises the following raw materials in parts by weight: IPDI aliphatic isocyanate prepolymer: 5-10 parts; HDI trimer: 60-70 parts; Solvent: 20-35 parts; The additives mentioned above are a mixture of dispersants, defoamers, light stabilizers, ultraviolet absorbers, leveling agents, anti-settling agents, and silane coupling agents. The polyaspartic ester resin is Desmophen ® NH 1420; The IPDI aliphatic isocyanate prepolymer is WANNATE. ® IT-2100 2. The aspartic polyurea anticorrosive coating according to claim 1, characterized in that, The inorganic filler is a mixture of zinc phosphate, mica powder and precipitated barium sulfate, with a mass ratio of (10-14):(10-13):

10.

3. The aspartic polyurea anticorrosive coating according to claim 1, characterized in that, The pigment is an oil-based pigment.

4. The aspartic polyurea anticorrosive coating according to claim 1, characterized in that, The solvent is one or more of butyl acetate or propylene glycol methyl ether acetate.

5. The aspartic polyurea anticorrosive coating according to claim 1, characterized in that, The HDI trimer is WANNATE. ® HT-100.

6. The aspartic polyurea anticorrosive coating according to claim 1, characterized in that, The dispersant is DisuperS4; the defoamer is Defom 6800.

7. The aspartic polyurea anticorrosive coating according to claim 1, characterized in that, The light stabilizer is UNIQLIGHT 992; the ultraviolet absorber is UNIQLIGHT 930; the leveling agent is DISPARLON L-1983N; the anti-settling agent is BYK-410; and the silane coupling agent is KH-560.

8. A method for preparing an aspartic polyurea anticorrosive coating according to any one of claims 1-7, characterized in that, Includes the following steps: (1) Mix polyaspartic acid ester resin, hydroxyl-terminated polybutadiene acrylonitrile, inorganic filler, dispersant and defoamer, dehydrate under vacuum and cool to below 60°C, add color paste, light stabilizer, ultraviolet absorber, leveling agent, anti-settling agent and silane coupling agent and disperse evenly, finally add solvent and stir evenly to obtain component A. (2) Mix IPDI aliphatic isocyanate prepolymer, HDI trimer and solvent and stir until homogeneous to obtain component B; (3) When using, mix component A and component B, apply evenly to the substrate, and after curing, you will get aspartic polyurea anti-corrosion coating.

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