Quick-drying acrylic polyurethane composition

Abstract

The invention provides a quick-drying acrylic polyurethane composition, and relates to the technical field of acrylic polyurethane. According to the invention, the low-viscosity and quick-drying first aspartic ester resin is added into the raw material components of the acrylic polyurethane, and plays a role of an active diluent in the acrylic polyurethane composition, so that the viscosity of the acrylic polyurethane composition is obviously reduced, and the curing rate of the acrylic polyurethane is accelerated; the technical effect of quick drying is achieved.

Description

Technical Field

[0001] This invention belongs to the field of acrylic polyurethane technology and relates to a fast-drying acrylic polyurethane composition. Background Technology

[0002] Acrylic polyurethane is a two-component self-drying coating, composed of a hydroxyl component (the main resin is an acrylic resin with a high hydroxyl content) and an isocyanate curing agent component. It possesses excellent weather resistance, chemical stability, and mechanical properties, strong adhesion, and outstanding gloss and color retention. Acrylic resin can be applied by spraying or rolling, and requires a matching thinner. Currently, there are two types of thinners for acrylic polyurethane: non-reactive and reactive. Reactive thinners participate in the curing reaction of acrylic polyurethane, reducing the VOC content of the raw materials and offering better environmental friendliness. Polyaspartic acid ester resin contains two secondary amine groups in its structure, allowing for faster curing with isocyanate curing agents, and thus has potential applications as a reactive thinner for acrylic polyurethane. Chinese patent CN104804633A discloses a low-temperature fast-drying acrylic polyurethane coating, which uses modified polyaspartic acid ester as the active diluent. However, according to its structure, the modified polyaspartic acid ester is actually F420 resin from Feiyang Junyan Company or 1420 resin from Bayer. Its viscosity at 25°C is about 1300 mPa·s, which is relatively high and the dilution effect is generally poor.

[0003] Therefore, further optimization is needed for polyaspartic acid ester resin reactive diluents for acrylic polyurethane. Summary of the Invention

[0004] To address the aforementioned technical problems, the present invention provides a fast-drying acrylic polyurethane composition.

[0005] The technical solution of the present invention is as follows:

[0006] A fast-drying acrylic polyurethane composition comprising component A and component B;

[0007] The raw material components of component A include acrylic resin and acepartic acid ester resin;

[0008] The viscosity of the first aspartic acid ester resin at 25°C does not exceed 500 mPa·s, and the pot life of the first aspartic acid ester resin at 25°C is 45-55 min.

[0009] The test method for the applicable period is as follows: at 25°C, the first day aspartic acid ester resin and HT-600 curing agent are mixed at a molar ratio of NH group and NCO group of 1:1, and the time it takes for the viscosity to rise to 10000 mPa.s is tested using an NDJ-5S rotational viscometer.

[0010] Component B is an isocyanate curing agent.

[0011] Preferably, the acrylic resin accounts for no less than 50% by weight of the raw material components of component A, and the hydroxyl content of the acrylic resin is 1-5 wt%.

[0012] Preferably, the first polyaspartic ester resin accounts for 5-40% by weight of the raw material components in component A.

[0013] Preferably, the structure of the first aspartic acid ester resin is shown in formula (1).

[0014]

[0015] R1 is selected from C5-C7 cycloalkylene or C6-C10 substituted cycloalkylene, and R2 and R3 are individually selected from C1-C4 alkylene, m = 2-3.

[0016] More preferably, the substituents of the C6-C10 substituted cycloalkyl group are C1-C3 alkyl groups or halogens.

[0017] Preferably, the raw material component of component A includes 2-aspartic acid ester resin;

[0018] The second aspartic acid ester resin is selected from monofunctional aspartic acid ester resins and / or asymmetric difunctional aspartic acid ester resins.

[0019] The asymmetric bifunctional aspartic acid ester resin refers to a resin in which two NH groups have different chemical environments.

[0020] More preferably, the second teraspartic acid ester resin accounts for no more than 20% by weight of the raw material components of component A.

[0021] Preferably, the monofunctional aspartic acid ester resin has the structure shown in formula (2).

[0022]

[0023] R4, R5 and R6 are individually selected from C1-C4 alkyl groups.

[0024] Preferably, the asymmetric bifunctional aspartic ester resin has the structure shown in formula (3).

[0025]

[0026] Among them, R7 and R8 are individually selected from H or C1-C4 alkyl groups, and R7 and R8 are not both H; R9 and R 10 Individually selected from C1-C3 alkyl groups, R 11 and R12 The individual is selected from C4-C8 alkyl groups.

[0027] Preferably, the ratio of the sum of the equivalent amounts of NH groups and OH groups in component A to the equivalent amount of NCO groups in component B is 1:1-1.15.

[0028] The beneficial effects of this invention are:

[0029] (1) The present invention uses low viscosity acepartic acid ester resin as an active diluent for acrylic polyurethane, which has a significant viscosity reduction effect. Moreover, acepartic acid ester resin can participate in the curing reaction of acrylic polyurethane and has high reactivity, which can make the acrylic polyurethane composition have high solid content, low viscosity and fast drying effect.

[0030] (2) The acrylic polyurethane composition of the present invention may be further supplemented with teraspartic acid ester resin to further adjust the drying performance, viscosity and solid content of acrylic polyurethane to meet different construction requirements. Detailed Implementation

[0031] The technical solution of the present invention will be further explained and described below through specific embodiments.

[0032] To optimize the performance of polyaspartic acid ester resin as an active diluent for acrylic polyurethane, this invention proposes a fast-drying acrylic polyurethane composition, consisting of component A and component B.

[0033] The raw material components of component A include acrylic resin and acepartic acid ester resin;

[0034] The viscosity of the aspartic acid ester resin at 25℃ on the first day does not exceed 500 mPa·s, and the pot life of the aspartic acid ester resin at 25℃ on the first day is 45-55 min.

[0035] The test method for the pot life is as follows: at 25℃, on the first day, after mixing aspartic acid ester resin and HT-600 curing agent at a molar ratio of NH group and NCO group of 1:1, the time it takes for the viscosity to rise to 10000 mPa.s is measured using an NDJ-5S rotational viscometer.

[0036] Component B is an isocyanate curing agent.

[0037] The present invention incorporates a low-viscosity ethyl aspartic acid ester resin as an active diluent into the acrylic polyurethane composition. This diluent possesses both low viscosity and good viscosity-reducing effect, as well as fast-drying properties, significantly improving the drying speed of the acrylic polyurethane. Furthermore, the ethyl aspartic acid ester resin contains 2-3 NH groups.

[0038] For the viscosity of the first-day aspartic ester resin at 25°C, for example, it can be any value or any value between 150 mPa·s, 200 mPa·s, 250 mPa·s, 300 mPa·s, 350 mPa·s, 400 mPa·s, 450 mPa·s, and 500 mPa·s, without particular limitation. Furthermore, the viscosity of the first-day aspartic ester resin at 25°C can not exceed 300 mPa·s.

[0039] For example, the pot life of the first primordial aspartic acid ester resin at 25°C can be 45 min, 46 min, 47 min, 48 min, 49 min, 50 min, 51 min, 52 min, 53 min, 54 min, 55 min, etc. For comparison, following the same pot life test method, the pot life of Feiyang Junyan's F420 resin and Bayer's 1420 resin at 25°C was measured to be 20-28 min. There are slight differences between different batches; for example, one batch of F420 resin tested had a pot life of 24 min.

[0040] In some embodiments, the acrylic resin accounts for no less than 50% by weight of the raw material component A, and the hydroxyl content of the acrylic resin is 1-5 wt%. For example, the weight percentage of the acrylic resin in the raw material component A can be any value or any value between 50%, 55%, 60%, 65%, 70%, 75%, 80%, etc., without particular limitation; the hydroxyl content of the acrylic resin can be any value or any value between 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, 5 wt%, etc., without particular limitation. Acrylic resins can be obtained directly from the market, such as CFU4270 and CFU2570A from Shandong Kafule, 9570 from Jiangsu Sanmu, and Setalux1753SS-70 from Nuplex, etc.

[0041] In some embodiments, the first polyaspartic ester resin accounts for 5-40% of the weight of the raw material components in component A. For example, the weight percentage can be any value or any value between 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, etc., without any particular limitation.

[0042] In some embodiments, the structure of the first acetic acid ester resin is shown in formula (1).

[0043]

[0044] R1 is selected from C5-C7 cycloalkylene or C6-C10 substituted cycloalkylene, and R2 and R3 are individually selected from C1-C4 alkylene, m = 2-3.

[0045] The first aspartic acid ester resin shown in the above formula (1) has a smaller R1 structure in the middle. Compared with existing polyaspartic acid ester resins (such as F420 resin and F520 resin of Feiyang Junyan Company), the first aspartic acid ester resin has a lower viscosity and higher reactivity. Therefore, as an active diluent for acrylic polyurethane, it has better dilution properties and also has a fast drying effect.

[0046] Furthermore, the substituents of the C6-C10 substituted cycloalkyl groups are C1-C3 alkyl groups or halogens. For example, the substituents can be methyl, ethyl, isopropyl, chlorine, bromine, etc.

[0047] The first aspartic acid ester resin of the present invention can be made from the corresponding first polyamine R1(NH2). m It is known to those skilled in the art to be obtained by a Maillard addition reaction with the first ester compound R2OOCCH=CHCOOR3.

[0048] Regarding the aforementioned first polyamine R1(NH2) m Examples of such compounds include 1,4-hexanediamine, 1,3-hexanediamine, 2-methyl-1,4-hexanediamine, 2-chloro-1,4-hexanediamine, 2-ethyl-1,4-hexanediamine, 1,2-hexanediamine, 1,3-pentanediamine, and 1,2-pentanediamine. Examples of the aforementioned first ester compounds include dimethyl maleate, diethyl maleate, diisobutyl maleate, dimethyl fumarate, and diethyl fumarate.

[0049] In some embodiments, the raw material component of component A includes daidzinyl ester resin;

[0050] The second-day aspartic ester resin is selected from monofunctional aspartic ester resin and / or asymmetric difunctional aspartic ester resin.

[0051] Asymmetric bifunctional aspartic acid ester resins refer to resins in which two NH groups have different chemical environments.

[0052] Monofunctional aspartic acid ester resins or asymmetric difunctional aspartic acid ester resins have a viscosity at 25°C not exceeding 500 mPa·s, or further, not exceeding 300 mPa·s, thus acting as reactive diluents. Monofunctional aspartic acid ester resins, in particular, have even lower viscosity at 25°C, not exceeding 50 mPa·s, exhibiting better dilution effects. However, adding too much may affect the curing of acrylic polyurethane, resulting in incomplete curing or insufficient crosslinking density.

[0053] Furthermore, the weight percentage of the second aspartic ester resin in the raw material component of component A shall not exceed 20%. For example, the weight percentage of the second aspartic ester resin in the raw material component of component A can be any value or any value between 3%, 5%, 10%, 15%, and 20%, without any particular restriction. Especially when the second aspartic ester resin is a monofunctional aspartic ester resin, if the content of the monofunctional aspartic ester resin in the raw material component of component A is too high, it will affect the drying speed of the fast-drying acrylic polyurethane composition, and may even result in poor drying performance or too low crosslinking density, affecting the performance of the acrylic polyurethane. For asymmetric difunctional aspartic ester resins, the two NH groups have different chemical environments, resulting in different reactivity of the two NH groups. This allows adjustment of the curing rate of the acrylic polyurethane, for example, a slower curing rate in the early stage of curing and a faster curing rate in the later stage of curing, providing better operability.

[0054] In some embodiments, the monofunctional aspartic ester resin has the structure shown in formula (2).

[0055]

[0056] R4, R5 and R6 are individually selected from C1-C4 alkyl groups.

[0057] The aforementioned monofunctional aspartic acid ester resins can be obtained by a Michael addition reaction between the corresponding cyclohexylamine or substituted cyclohexylamine (such as cyclohexylamine, 2-methylcyclohexylamine, 3-methylcyclohexylamine, 2-ethylcyclohexylamine, etc.) and a second ester compound R5OCOCH=CHCOOR6. The second ester compound can be dimethyl maleate, diethyl maleate, diisobutyl maleate, dimethyl fumarate, diethyl fumarate, etc.

[0058] In some embodiments, the asymmetric bifunctional aspartic ester resin has the structure shown in formula (3).

[0059]

[0060] Among them, R7 and R8 are individually selected from H or C1-C4 alkyl groups, and R7 and R8 are not both H; R9 and R 10 Individually selected from C1-C3 alkyl groups, R 11 and R 12 Individually selected from C4-C8 alkyl groups. Due to the influence of R9, R 10 R 11 and R 12 Due to the different steric hindrances of R7 and R8, the reactivity of the two NH groups of the second aspartic acid ester resin shown in formula (3) is different, and the second aspartic acid ester resin has a lower viscosity.

[0061] For the aforementioned asymmetric bifunctional aspartic acid ester resin, it can be produced by sequentially reacting the corresponding second polyamine with a third ester compound R. 11 OCOCH=CHCOOR 12 And the fourth ester compound R9OCOCH=CHCOOR 10 Obtained by performing a Michael addition reaction.

[0062] For the second polyamine, the structure

[0063] The meanings of R7 and R8 are as described above. For example, the second polyamine can be 2,4-dimethyl-1,3-cyclohexanediamine, 2-methyl-1,3-cyclohexanediamine, 4-methyl-1,3-cyclohexanediamine, etc. For the third ester compound, examples include di-n-butyl maleate, di-n-hexyl maleate, di-n-octyl maleate, diisobutyl maleate, diisooctyl maleate, etc. For the fourth ester compound, examples include dimethyl maleate, diethyl maleate, diisopropyl maleate, etc.

[0064] In some embodiments, the ratio of the sum of the equivalent amounts of NH groups and OH groups in component A to the equivalent amount of NCO groups in component B is 1:1-1.15. For example, the equivalent ratio can be any value or any value between 1:1, 1:1.02, 1:1.05, 1:1.08, 1:1.1, 1:1.12, 1:1.15, etc., without any particular limitation.

[0065] In this invention, the raw material components of component A may further include fillers, additives, pigments, organic solvents, etc. Fillers can be inorganic fillers, such as talc, kaolin, wollastonite, glass microspheres, glass fiber, carbon fiber, mica sheets, graphene, silica, alumina, etc., or organic fillers, such as polyethylene (PE) micropowder, polytetrafluoroethylene (PTFE) micropowder, etc. Additives can be leveling agents, wetting agents, defoamers, UV absorbers, thickeners, thixotropic agents, antioxidants, anti-settling agents, dispersants, etc. Pigments can be inorganic or organic pigments. Organic solvents can be butyl acetate, propylene glycol methyl ether acetate (PMA), xylene, propylene glycol dimethyl ether, etc.

[0066] In this invention, the isocyanate curing agent of component B is not particularly limited and can be any one or a combination of two or more of the following: diisocyanate monomers (such as IPDI, HMDI, HDI, etc.), adducts of diisocyanate monomers and polymer diols (such as polyether diol, polyester diol, etc.), and diisocyanate monomer trimers (such as HDI trimers, IPDI trimers).

[0067] Commonly used isocyanate curing agents for component B include Wanhua HT-100, Wanhua HT-300, Wanhua HT-600, and Asahi Kasei TPA-100.

[0068] There are no particular limitations on the preparation method of the acrylic polyurethane composition of the present invention. One method may be: after the raw material components of component A are mixed and dispersed evenly, component A is obtained; before use, component A and component B are mixed evenly to obtain the final product.

[0069] The technical solution of the present invention will be further described and explained below with reference to various preparation examples and embodiments. Unless otherwise specified, the parts mentioned in the following preparation examples and embodiments are parts by weight.

[0070] Preparation Examples 1-2: Preparation of First-Standardized Aspartate Resin

[0071] Preparation Example 1

[0072] 1 mol of 1,4-cyclohexanediamine and 2.4 mol of diethyl maleate were added to a reaction vessel, heated to 100℃ and reacted for 48 h. The unreacted raw materials were removed by heating to 150℃ and reducing the pressure to below -0.099 MPa to obtain 1-day aspartic acid ester resin with a viscosity (25℃) of 310 mPa·s.

[0073] Preparation Example 2

[0074] 1 mol of 1,3-cyclopentanediamine and 2.2 mol of diethyl maleate were added to a reaction vessel, heated to 100℃ and reacted for 48 h. The unreacted raw materials were removed by heating to 150℃ and reducing the pressure to below -0.099 MPa to obtain 1-day aspartic acid ester resin with a viscosity (25℃) of 270 mPa·s.

[0075] Preparation Examples 3-8: Preparation of mixed solutions of acrylic resin and dextrin ester resin

[0076] In the following preparation examples, the acrylic resin used is CFU4270 from Shandong Kafule, with a solid content of 70 wt% and a viscosity of 4180 mPa·s at 25°C.

[0077] Preparation Example 3

[0078] The first-day aspartic acid ester resin obtained in Preparation Example 1 was diluted with butyl acetate to a solution with a solid content of 70 wt%, and then mixed with the above-mentioned acrylic resin at a weight ratio of 1:9 to obtain a mixed solution.

[0079] Preparation Example 4

[0080] The first-day aspartic acid ester resin obtained in Preparation Example 1 was diluted with butyl acetate to a solution with a solid content of 70 wt%, and then mixed with the above-mentioned acrylic resin at a weight ratio of 2:8 to obtain a mixed solution.

[0081] Preparation Example 5

[0082] The first-day aspartic acid ester resin obtained in Preparation Example 1 was diluted with butyl acetate to a solution with a solid content of 70 wt%, and then mixed with the above-mentioned acrylic resin at a weight ratio of 3:7 to obtain a mixed solution.

[0083] Comparative Preparation Example 1

[0084] The F420 resin of Feiyang Junyan was dissolved in butyl acetate to prepare a solution with a solid content of 70 wt%, and then mixed with the above acrylic resin at a weight ratio of 3:7 to obtain a mixed solution.

[0085] Comparative Preparation Example 2

[0086] The F520 resin of Feiyang Junyan was dissolved in butyl acetate to prepare a solution with a solid content of 70 wt%, and then mixed with the above acrylic resin at a weight ratio of 3:7 to obtain a mixed solution.

[0087] Preparation Example 6

[0088] The first-day aspartic acid ester resin obtained in Preparation Example 1 was diluted with butyl acetate to a solution with a solid content of 70 wt%, and then mixed with the above-mentioned acrylic resin and second-day aspartic acid ester resin solution at a weight ratio of 3:5:2 to obtain a mixed solution.

[0089] The solid content of the aspartic acid ester resin solution on the second day was 70 wt%. The aspartic acid ester resin solution on the second day was prepared as follows:

[0090] The equivalent ratio of 2,4-dimethyl-1,3-cyclohexanediamine, di-n-butyl maleate, and diethyl maleate is 1:1.08:1.02.

[0091] At room temperature, 2,4-dimethyl-1,3-cyclohexanediamine was added to a reaction vessel, and the reaction system temperature was controlled to not exceed 40°C. Di-n-butyl maleate was added dropwise, and after the addition was complete, the temperature was raised to 40-45°C and reacted for 24 hours, then raised to 55-60°C and reacted for another 24 hours. The reaction system temperature was then controlled to not exceed 45°C, and diethyl maleate was added dropwise. After the addition was complete, the temperature was raised to 50-55°C and reacted for 96 hours, then continued to react at 55-60°C for 48 hours to obtain the first-day aspartic acid ester resin. The viscosity at 25°C was measured to be 260 mPa·s using an NDJ-5S rotational viscometer. The first-day aspartic acid ester resin was dissolved in butyl acetate to obtain the second-day aspartic acid ester resin solution.

[0092] Preparation Example 7

[0093] The first-day aspartic acid ester resin obtained in Preparation Example 2 was diluted with butyl acetate to a solution with a solid content of 70 wt%, and then mixed with the above-mentioned acrylic resin at a weight ratio of 4:6 to obtain a mixed solution.

[0094] Preparation Example 8

[0095] The first-day aspartic acid ester resin obtained in Preparation Example 2 was diluted with butyl acetate to a solution with a solid content of 70 wt%, and then mixed with the above-mentioned acrylic resin and second-day aspartic acid ester resin solution at a weight ratio of 3:6:1 to obtain a mixed solution.

[0096] The second-side aspartic acid ester resin solution was prepared as follows: 1 mol of cyclohexylamine was added to a reaction vessel, and 1.2 mol of diethyl maleate was added dropwise. The mixture was heated to 100℃ and reacted for 24 h. The pressure was reduced to below -0.099 MPa to remove unreacted raw materials, yielding the second-side aspartic acid ester resin with a viscosity (25℃) of 11 mPa·s. The second-side aspartic acid ester resin was dissolved in butyl acetate to prepare a second-side aspartic acid ester resin solution with a solid content of 70 wt%.

[0097] The mixed solutions of Preparation Examples 3-8 and Comparative Preparation Examples 1-2 were tested using an NDJ-5S rotational viscometer, and the results are shown in Table 1 below.

[0098] Table 1 Viscosity / mPa·s

[0099]

[0100] Therefore, as shown in Table 1 above, the addition of the acepartic acid ester resin of the present invention to acrylic resin has a significant viscosity-reducing effect. Even with only 10% (1:9 in Preparation Example 3), the viscosity reduction can reach 60%, and with 30% (3:7 in Preparation Example 5), the viscosity reduction can approach 90%. This allows for improved construction efficiency through spraying and other application processes. In contrast, the viscosity-reducing effect of F420 and F520 resins on acrylic resin is far less than that of the acepartic acid ester resin of the present invention.

[0101] Example 1

[0102] The fast-drying acrylic polyurethane composition consists of component A and component B.

[0103] The raw material composition of component A is: 500 parts of the mixed solution of Preparation Example 3, 350 parts of titanium dioxide, 15 parts of ultraviolet absorber, 6 parts of polyether modified silicone oil wetting agent, 7 parts of dimethyl silicone oil defoamer, and 122 parts of mixed solvent (composed of butyl acetate and PMA in a weight ratio of 1:2).

[0104] Component B: HT-600 curing agent.

[0105] The equivalent ratio of active hydrogen in component A to NCO groups in component B is 1:1.06.

[0106] Component A and component B are mixed and stirred until homogeneous to obtain a polyurethane composition.

[0107] Example 2

[0108] The difference between this embodiment and Example 1 is that in Example 1, 500 parts of the mixed solution of Preparation Example 3 were replaced with 500 parts of the mixed solution of Preparation Example 4. The remaining steps remain unchanged.

[0109] Example 3

[0110] The difference between this embodiment and Example 1 is that in Example 1, 500 parts of the mixed solution of Preparation Example 3 were replaced with 500 parts of the mixed solution of Preparation Example 5. The remaining steps remained unchanged.

[0111] Example 4

[0112] The difference between this embodiment and Embodiment 1 is that in Embodiment 1, 500 parts of the mixed solution of Preparation Example 3 were replaced with 500 parts of the mixed solution of Preparation Example 6. The remaining steps remain unchanged.

[0113] Example 5

[0114] The difference between this embodiment and Example 1 is that in Example 1, 500 parts of the mixed solution of Preparation Example 3 were replaced with 500 parts of the mixed solution of Preparation Example 7. The remaining steps remain unchanged.

[0115] Example 6

[0116] The difference between this embodiment and Example 1 is that in Example 1, 500 parts of the mixed solution of Preparation Example 3 were replaced with 500 parts of the mixed solution of Preparation Example 8. The remaining steps remain unchanged.

[0117] Comparative Example 1

[0118] The difference between this comparative example and Example 1 is that in Example 1, 500 parts of the mixed solution of Preparation Example 3 were replaced with 500 parts of the mixed solution of Comparative Preparation Example 1. The remaining steps remained unchanged.

[0119] Comparative Example 2

[0120] The difference between this comparative example and Example 1 is that in Example 1, 500 parts of the mixed solution of Preparation Example 3 were replaced with 500 parts of the mixed solution of Comparative Preparation Example 2. All other steps remained unchanged.

[0121] Comparative Example 3

[0122] The difference between this comparative example and Example 1 is that in Example 1, 500 parts of the mixed solution of Preparation Example 3 were replaced with 500 parts of CFU4270 acrylic resin from Shandong Kafule. The remaining steps remained unchanged.

[0123] The properties of the fast-drying polyurethane compositions of Examples 1-6 and Comparative Examples 1-3 are shown in Table 2 below, where OK indicates pass and NG indicates fail.

[0124] Table 2

[0125]

[0126] As shown in Table 2 above, the addition of low-viscosity, highly active dextrin ester resin as an active diluent to acrylic resin in this invention can accelerate the drying speed of acrylic polyurethane, significantly shortening both surface drying and complete drying times, while still maintaining a relatively long pot life. Furthermore, it has virtually no impact on the performance of the acrylic polyurethane coating, maintaining its good performance. In contrast, using F420 or F520 resin as an active diluent does not have the same viscosity-reducing effect as the dextrin ester resin of this invention. Moreover, using F420 resin results in excessively fast drying and a very short pot life, which is detrimental to construction operations and significantly worsens adhesion. Using F520 resin results in slower drying and also worsens adhesion.

[0127] As described above, the basic principles, main features, and advantages of the present invention have been shown and described. Those skilled in the art should understand that the present invention is not limited to the above embodiments, which are merely preferred embodiments and should not be construed as limiting the scope of the invention. All equivalent changes and modifications made in accordance with the scope of the patent and the description should still fall within the scope of the present invention. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A fast-drying acrylic polyurethane composition, characterized in that, It consists of component A and component B; The raw material components of component A include acrylic resin and acepartic acid ester resin; The viscosity of the first aspartic acid ester resin at 25°C does not exceed 500 mPa·s, and the pot life of the first aspartic acid ester resin at 25°C is 45-55 min. The test method for the applicable period is as follows: at 25°C, the first day aspartic acid ester resin and HT-600 curing agent are mixed at a molar ratio of NH group and NCO group of 1:1, and the time it takes for the viscosity to rise to 10000 mPa.s is tested using an NDJ-5S rotational viscometer. Component B is an isocyanate curing agent.

2. The fast-drying acrylic polyurethane composition according to claim 1, characterized in that, The acrylic resin accounts for no less than 50% of the weight of the raw material components in component A, and the hydroxyl content of the acrylic resin is 1-5 wt%.

3. The fast-drying acrylic polyurethane composition according to claim 1, characterized in that, The first polyaspartic ester resin accounts for 5-40% by weight of the raw material components in component A.

4. The fast-drying acrylic polyurethane composition according to claim 1, characterized in that, The structure of the first aspartic acid ester resin is shown in formula (1). R1 is selected from C5-C7 cycloalkylene or C6-C10 substituted cycloalkylene, and R2 and R3 are individually selected from C1-C4 alkylene, m = 2-3.

5. The fast-drying acrylic polyurethane composition according to claim 4, characterized in that, The substituents of the C6-C10 substituted cycloalkyl group are C1-C3 alkyl groups or halogens.

6. The fast-drying acrylic polyurethane composition according to claim 1, characterized in that, The raw material components of component A include 2-aspartic acid ester resin; The second aspartic acid ester resin is selected from monofunctional aspartic acid ester resins and / or asymmetric difunctional aspartic acid ester resins. The asymmetric bifunctional aspartic acid ester resin refers to a resin in which two NH groups have different chemical environments.

7. The fast-drying acrylic polyurethane composition according to claim 6, characterized in that, The second tertiary aspartate resin accounts for no more than 20% by weight of the raw material components in component A.

8. The fast-drying acrylic polyurethane composition according to claim 1, characterized in that, The monofunctional aspartic acid ester resin has the structure shown in formula (2). R4, R5 and R6 are individually selected from C1-C4 alkyl groups.

9. The fast-drying acrylic polyurethane composition according to claim 1, characterized in that, The asymmetric bifunctional aspartic acid ester resin has the structure shown in formula (3). Among them, R7 and R8 are individually selected from H or C1-C4 alkyl groups, and R7 and R8 are not both H; R9 and R 10 Individually selected from C1-C3 alkyl groups, R 11 and R 12 The individual is selected from C4-C8 alkyl groups.

10. The fast-drying acrylic polyurethane composition according to claim 1, characterized in that, The ratio of the sum of the equivalent amounts of NH groups and OH groups in component A to the equivalent amount of NCO groups in component B is 1:1-1.15.

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