Solvent-free polyaspartic acid ester polyurea coating as well as preparation method and application thereof

Abstract

The invention provides a solvent-free polyaspartic acid ester polyurea coating as well as a preparation method and application thereof, and relates to the field of coatings, the coating comprises colored paint and a curing agent, and the mass ratio of the colored paint to the curing agent is (20-25): (7.8-10); the colored paint is prepared from the following raw materials in percentage by mass: 30 to 60 percent of polyaspartic acid ester, 0.2 to 0.8 percent of dispersing agent, 0.1 to 1.0 percent of defoaming agent, 0.1 to 0.3 percent of flatting agent, 0.3 to 1.0 percent of fumed silica, 5 to 10 percent of molecular sieve, 40 to 50 percent of barium sulfate and 0 to 20 percent of color paste; the curing agent is a modified HDI tripolymer. The radix asparagi polyurea coating has both long construction time (25-30 min) and quick drying (lt: 3 h).

Description

Technical Field

[0001] This invention relates to the field of coatings, and more specifically, to a solvent-free polyaspartic acid ester polyurea coating, its preparation method, and its application. Background Technology

[0002] Currently, solvent-free self-leveling floor coatings are mainly solvent-free epoxy self-leveling coatings. However, solvent-free epoxy flooring has many disadvantages, including a strong amine odor, long construction period, poor acid resistance, easy cracking, poor weather resistance, and failure to cure at low temperatures. Solvent-free polyaspartic ester polyurea coatings (referred to as aspartic polyurea) have advantages such as being environmentally friendly and almost odorless, curing at low temperatures, excellent toughness, acid and alkali resistance, waterproofing, corrosion resistance, and good weather resistance, making them very suitable as high-end floor coatings. However, isocyanates are sensitive to moisture, and when the coating film is too thick (>500µm), it is prone to blistering. Even thin coatings (>100µm) will have bubbles on the surface under high humidity conditions. Although fast-drying aspartic polyurea (such as F420 or Desmophen® NH 1420 systems) reduce the impact of moisture on the coating film by drying quickly, the short gel time due to the rapid drying requires the addition of a large amount of solvent to extend the construction time. Summary of the Invention

[0003] The purpose of this invention is to provide a solvent-free polyaspartic ester polyurea coating. This aspartic polyurea coating allows for true solvent-free self-leveling application while balancing a long application time (25-30 min) and fast drying (<3 h). Furthermore, while maintaining a long application time and good surface finish, the hardness and flexibility of this aspartic polyurea can be adjusted within a wide range as needed.

[0004] Another objective of this invention is to provide a method for preparing solvent-free polyaspartic acid ester polyurea coatings, wherein the coatings prepared by this method can achieve a balance between long application time and fast drying.

[0005] The technical problem solved by this invention is achieved by the following technical solution.

[0006] On one hand, embodiments of the present invention provide a solvent-free polyaspartic acid ester polyurea coating, comprising a color paint and a curing agent, wherein the mass ratio of the color paint to the curing agent is 20-25:7.8-10; By mass fraction, the paint comprises the following raw materials: 30-60% polyaspartic acid ester, 0.2-0.8% dispersant, 0.1-1.0% defoamer, 0.1-0.3% leveling agent, 0.3-1.0% fumed silica, 5-10% molecular sieve, 40-50% barium sulfate, and 0-20% color paste; The curing agent is a modified HDI trimer.

[0007] In some embodiments of the present invention, the preparation method of the modified HDI trimer includes the following steps: reacting a long-chain epoxy compound with a long-chain acid compound at 120°C to obtain an ester containing a secondary hydroxyl group; adding the secondary hydroxyl ester to the HDI trimer dropwise at 50-90°C; and gradually increasing the temperature until the NCO reaches the reaction endpoint to obtain the modified HDI trimer.

[0008] In some embodiments of the present invention, the long-chain epoxy compound is at least one of the following monofunctional glycidyl ethers: C12-C14 glycidyl ether, C8-C10 glycidyl ether, tert-carbonate glycidyl ether, (3-epoxypropoxy)propyltrimethoxysilane, butyl glycidyl ether, benzyl glycidyl ether, allyl glycidyl ether, isopropyl glycidyl ether, octyl glycidyl ether, methoxy polyethylene glycol glycidyl ether, p-tert-butylphenyl glycidyl ether, and decyl glycidyl ether.

[0009] In some embodiments of the present invention, the long-chain acid compound is at least one selected from undecanoic acid, lauric acid, oleic acid, nonanoic acid, octanoic acid, valproic acid, tetradecanoic acid, hexadecanoic acid, nonadecanoic acid, isovaleric acid, and isobutyric acid.

[0010] In some embodiments of the present invention, the HDI trimer may be at least one of HT-300, HT-600, HT-100, HT-500, N3900, N3300, and N3600.

[0011] In some embodiments of the present invention, the polyaspartic ester has a high solids content and a low primary amine content, and is at least one of Desmophen® NH 1520, Desmophen® NH 1420, F520, F420, F2850, and F2401.

[0012] On the other hand, the present invention provides a method for preparing a solvent-free polyaspartic ester polyurea coating, comprising the following steps: Polyaspartic acid ester, dispersant, defoamer, and leveling agent are mixed evenly using a high-speed disperser at a speed of 1000-1200 r / min for 10-20 min. Then, fumed silica, molecular sieve, barium sulfate, and color paste are added at a speed of 2000-2500 r / min for 30-40 min to obtain a colored paint. The colored paint is then mixed with a curing agent according to the mass ratio to obtain a polyaspartic acid ester polyurea coating.

[0013] Thirdly, embodiments of the present invention provide an application of solvent-free polyaspartic acid ester polyurea coating in self-leveling floor coatings.

[0014] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: 1. The polyaspartic ester polyurea coating prepared by this invention can achieve truly solvent-free self-leveling application while balancing a long application time (30 min) and fast drying (3 h to dry). By using a long-chain, high-steric-resistance modified HDI trimer as a curing agent, the NCO activity of the curing agent is reduced, and the overall wettability and leveling properties of the coating are improved. Therefore, the viscosity increase is slowed down over the same time period, and the coating exhibits better fluidity and leveling properties compared to coatings of the same viscosity, thus achieving truly solvent-free application while balancing a long application time and fast drying.

[0015] 2. The solvent-free aspartic polyurea self-leveling coating prepared by the present invention can be coated at least 2 mm thick, with a smooth and bubble-free surface and cross-section. The long-chain high steric hindrance modification of the HDI trimer curing agent reduces the NCO activity of the curing agent while improving wettability, thus reducing sensitivity to water vapor and accelerating the escape rate of internal mechanical bubbles and a small number of reaction bubbles.

[0016] 3. The polyaspartic acid ester polyurea coating prepared by this invention has excellent toughness while maintaining excellent durability, and can be adjusted as needed. The modified long chain of the HDI trimer curing agent is on the side group, which provides flexibility while having little impact on hardness. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 The coating of Example 1 was tested at 30°C and 99%RH at a concentration of 1 kg / m³. 2 Construction renderings, where a is the construction rendering after 0 minutes of mixing; b is the construction rendering after 30 minutes of mixing. Figure 2 This is a cross-sectional view of the coating of Example 1 applied in a thick coat at 30°C and 99%RH. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0020] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to specific embodiments.

[0021] Example 1 Prepare the modified HDI trimer by following these steps: Epoxy AGE was reacted with lauric acid at 120℃, and the ratio was carefully controlled to obtain an ester containing secondary hydroxyl groups. Then, a certain amount of the secondary hydroxyl ester was added dropwise to a three-necked flask containing HT-600 at 70℃. After the addition was complete, the temperature was gradually increased until NCO reached the reaction endpoint. Modified HDI trimer 1 with an NCO mass fraction of 12% was obtained.

[0022] Preparation of polyaspartic acid ester polyurea coating: The paint was prepared by mixing F520, F2850, dispersant BYK-163, defoamer BYK-1790, defoamer Tego airex 900, leveling agent TEG0-410, fumed silica DM-10, molecular sieve 3A activated powder, barium sulfate, and color paste in a mass ratio of 22.5:22.5:0.8:0.3:0.2:0.1:0.5:5:43.1:5. F520, F420, dispersant, defoamer, and leveling agent were then mixed uniformly at high speed using a high-speed disperser at 1000 r / min for 10 min. Then, fumed silica, molecular sieve, barium sulfate, and color paste were added, and the mixture was mixed at 2000 r / min for 30 min to obtain the paint. Next, the paint and modified HT-600 curing agent were mixed according to a mass ratio of 1:1.16 to obtain a polyaspartic acid ester polyurea coating.

[0023] Example 2 Prepare the modified HDI trimer by following these steps: Epoxy AGE was reacted with lauric acid at 120℃, and the ratio was carefully controlled to obtain an ester containing secondary hydroxyl groups. Then, a certain amount of the secondary hydroxyl ester was added dropwise to a three-necked flask containing HT-600 trimer at 70℃. After the addition was complete, the temperature was gradually increased until NCO reached the reaction endpoint. Modified HDI trimer 2 with an NCO mass fraction of 14% was obtained.

[0024] Preparation of polyaspartic acid ester polyurea coating: The following mixtures were prepared by mixing F520, F420, dispersant, defoamer, barium sulfate, and color paste in a high-speed disperser at a mass ratio of 22.5:22.5:0.8:0.3:0.2:0.1:0.5:5:43.1:5: F520, F420, dispersant, defoamer, and leveling agent uniformly at 1000 r / min for 10 min. Then, fumed silica, molecular sieve, barium sulfate, and color paste were added, and the mixture was stirred at 2000 r / min for 30 min to obtain the colored paint. Next, the colored paint and modified HDI trimer were mixed in a mass ratio of 1:1 to obtain a polyaspartic acid ester polyurea coating.

[0025] Example 3 Prepare the modified HDI trimer by following these steps: Epoxy AGE was reacted with lauric acid at 120℃, and the ratio was carefully controlled to obtain an ester containing secondary hydroxyl groups. Then, a certain amount of the secondary hydroxyl ester was added dropwise to a three-necked flask containing HT-300 trimer at 70℃. After the addition was complete, the temperature was gradually increased until NCO reached the reaction endpoint. Modified HDI trimer 3 with an NCO mass fraction of 12% was obtained.

[0026] Preparation of polyaspartic acid ester polyurea coating: The following mixtures were prepared by mixing F520, F420, dispersant, defoamer, barium sulfate, and color paste in a high-speed disperser at a mass ratio of 22.5:22.5:0.8:0.3:0.2:0.1:0.5:5:43.1:5: F520, F420, dispersant, defoamer, and leveling agent uniformly at 1000 r / min for 10 min. Then, fumed silica, molecular sieve, barium sulfate, and color paste were added, and the mixture was stirred at 2000 r / min for 30 min to obtain the colored paint. Next, the colored paint and modified HDI trimer were mixed in a mass ratio of 1:1 to obtain a polyaspartic acid ester polyurea coating.

[0027] Comparative Example 1 The curing agent used in this comparative example is the unmodified HT-600 curing agent.

[0028] Preparation of polyaspartic acid ester polyurea coating: The following mass ratios were used: F520:F2850: dispersant BYK-163: defoamer BYK-1790: defoamer Tego airex 900: leveling agent TEG0-410: fumed silica DM-10: molecular sieve 3A activated powder: barium sulfate: color paste = 22.5:22.5:0.8:0.3:0.2:0.1:0.5:5:43.1:5. F520, F420, dispersant, defoamer, and leveling agent were mixed uniformly at high speed using a high-speed disperser at 1000 r / min for 10 min. Then, fumed silica, molecular sieve, barium sulfate, and color paste were added, and the mixture was stirred at 2000 r / min for 30 min to obtain the colored paint. Next, the paint and HT-600 were mixed according to a mass ratio of 1:1.16 to obtain a polyaspartic acid ester polyurea coating.

[0029] Comparative Example 2 The curing agent used in this comparative example is the unmodified HT-300 curing agent.

[0030] Preparation of polyaspartic acid ester polyurea coating: The following mixture was prepared by mixing F520:F2850: dispersant BYK-163: defoamer BYK-1790: defoamer Tego airex 900: leveling agent TEG0-410: fumed silica DM-10: molecular sieve 3A activated powder: barium sulfate: color paste in a mass ratio of 30:15:0.8:0.3:0.2:0.1:0.5:5:43.1:5. F520, F420, dispersant, defoamer, and leveling agent were mixed uniformly at high speed using a high-speed disperser at 1000 r / min for 10 min. Then, fumed silica, molecular sieve, barium sulfate, and color paste were added, and the mixture was mixed at 2000 r / min for 30 min to obtain the colored paint. Next, the paint and HT-300 were mixed according to a mass ratio of 1:0.62 to obtain a polyaspartic acid ester polyurea coating.

[0031] Example of results: The coatings of Examples 1, 2, and 3, and Comparative Examples 1 and 2 were used as subjects for experimental testing, and the results are shown in Table 2. Table 1 compares the parameters of the curing agent in each coating.

[0032] Table 1 Comparison of parameters between modified HT-600 curing agent and HT-600 curing agent

[0033] Table 2 Comparison of the performance of various coatings

[0034] Table 2 shows that the coatings in Examples 1-4 can achieve a solvent-free coating volume of 1 kg / m³.2 The self-leveling application is successful, and with a 30-minute application time, it achieves a 3-hour drying time. Compared to the unmodified HT-600 (Comparative Example 1) and HT-300 (Comparative Example 2) curing agents, the modified curing agent exhibits a lower NCO mass percentage and, under the same resin conditions, longer surface and complete drying times, indicating a decreased reaction rate. Compared to the unmodified HT-600 / HT-300 curing agents, the modified curing agent, when combined with polyaspartic acid ester resin, exhibits better toughness. The modified curing agent, when combined with polyaspartic acid ester resin, at a rate of 1 kg / m³... 2 The surface finish after construction is better.

[0035] Figure 1 The coating of Example 1 was tested at 30°C and 99%RH at a concentration of 1 kg / m³. 2 Construction renderings, where a is the construction rendering after 0 minutes of mixing; b is the construction rendering after 30 minutes of mixing. Figure 2 This is a cross-sectional view of the coating of Example 1 applied in thick coat at 30°C and 99% RH. Figure 1 and Figure 2 As can be seen, there is no significant difference in curing after application whether the mixture is applied immediately or 30 minutes after application.

[0036] The embodiments described above are some, but not all, embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A solvent-free polyaspartic acid ester polyurea coating, characterized in that, It includes paint and a hardener, wherein the mass ratio of paint to hardener is (20-25):(7.8-10); By mass fraction, the paint comprises the following raw materials: 30-60% polyaspartic acid ester, 0.2-0.8% dispersant, 0.1-1.0% defoamer, 0.1-0.3% leveling agent, 0.3-1.0% fumed silica, 5-10% molecular sieve, 40-50% barium sulfate, and 0-20% color paste; The curing agent is a modified HDI trimer.

2. The solvent-free polyaspartic acid ester polyurea coating according to claim 1, characterized in that, The method for preparing the modified HDI trimer includes the following steps: At 120℃, a long-chain epoxy compound is reacted with a long-chain acid compound to obtain an ester containing a secondary hydroxyl group. The secondary hydroxyl ester is then added dropwise to an HDI trimer at 50-90℃. After the addition is complete, the temperature is gradually increased until the NCO reaches the reaction endpoint, thus obtaining a modified HDI trimer.

3. The solvent-free polyaspartic acid ester polyurea coating according to claim 2, characterized in that, The long-chain epoxy compound is a monofunctional glycidyl ether, including at least one of C12-C14 glycidyl ether, C8-C10 glycidyl ether, tert-carbonate glycidyl ether, (3-epoxypropoxy)propyltrimethoxysilane, butyl glycidyl ether, benzyl glycidyl ether, allyl glycidyl ether, isopropyl glycidyl ether, octyl glycidyl ether, methoxy polyethylene glycol glycidyl ether, p-tert-butylphenyl glycidyl ether, and decyl glycidyl ether.

4. The solvent-free polyaspartic acid ester polyurea coating according to claim 2, characterized in that, The long-chain acid compound is at least one of undecanoic acid, lauric acid, oleic acid, nonanoic acid, octanoic acid, valproic acid, tetradecanoic acid, hexadecanoic acid, nonadecanoic acid, isovaleric acid, and isobutyric acid.

5. The solvent-free polyaspartic acid ester polyurea coating according to claim 2, characterized in that, The HDI trimer may be at least one of HT-300, HT-600, HT-100, HT-500, N3900, N3300, and N3600.

6. The solvent-free polyaspartic acid ester polyurea coating according to claim 1, characterized in that, The polyaspartic ester is at least one of Desmophen® NH 1520, Desmophen® NH 1420, F520, F420, F2850, and F2401.

7. A method for preparing a solvent-free polyaspartic acid ester polyurea coating as described in any one of claims 1-6, characterized in that, Includes the following steps: Polyaspartic acid ester, dispersant, defoamer, and leveling agent are mixed evenly using a high-speed disperser at a speed of 1000-1200 r / min for 10-20 min. Then, fumed silica, molecular sieve, barium sulfate, and color paste are added at a speed of 2000-2500 r / min for 30-40 min to obtain a colored paint. The colored paint is then mixed with a curing agent according to the mass ratio to obtain a polyaspartic acid ester polyurea coating.

8. The application of a solvent-free polyaspartic acid ester polyurea coating as described in any one of claims 1-6, or / and the coating prepared by the method of claim 7, in self-leveling floor coatings.

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