Two-component waterborne polyurethane wear-resistant floor coating, its application and application methods

Abstract

This invention relates to a two-component waterborne polyurethane wear-resistant floor coating, its application, and application method. The raw materials of the two-component waterborne polyurethane wear-resistant floor coating include component A and component B. By mass fraction, component A comprises 45%-65% waterborne modified hydroxy acrylic dispersion, 15%-40% micron-sized filler, 1%-10% nano-sized filler, 5%-15% waterborne colorant, less than 10% additives, and 5%-15% water. The waterborne modified hydroxy acrylic dispersion is obtained by graft copolymerization, where silicone-modified polyurethane segments are used as soft segments and bonded to the waterborne hydroxy acrylic backbone. The mass ratio of the silicone-modified polyurethane segments to the waterborne hydroxy acrylic backbone is 1:1-1.5:1, and the iodine value of the waterborne modified hydroxy acrylic dispersion is 5-20. Component B is an isocyanate curing agent. The floor coating has excellent water resistance, acid resistance and wear resistance, and can be applied to the primer layer, leveling layer and topcoat layer at the same time, with high versatility.

Description

Technical Field

[0001] This invention relates to the field of coating technology, and in particular to a two-component waterborne polyurethane wear-resistant floor coating, its application, and application methods. Background Technology

[0002] Water-based floor coatings are a type of low-odor, green, and environmentally friendly material that meets national low-carbon and environmental protection requirements. They are applied to the ground to protect and decorate it. Based on the film-forming substance, they can be broadly classified into water-based epoxy floor coatings, water-based polyurethane floor coatings, and water-based acrylic floor coatings. However, traditional water-based floor coatings often have the following drawbacks during use:

[0003] (1) In terms of performance, firstly, the water resistance and acid resistance are poor. The main reason is that in order to meet the requirements of water-based coatings, most formulations introduce a large number of hydrophilic functional groups, such as hydroxyl, ether, carboxyl, and amine groups, which are very easy to form intermolecular hydrogen bonds with water, resulting in water molecules easily penetrating the paint film; secondly, the wear resistance is not strong enough. The main film-forming substance of water-based floor paint is water-based polyurethane. The hard segments in its molecular structure have high mechanical strength, which contributes significantly to wear resistance. When combined with isocyanate curing agents, a certain crosslinking density is formed to provide the coating wear resistance. Due to the viscosity of the water-based system, the crosslinking density of water-based polyurethane floor paint is low, and the wear resistance still cannot meet the growing demand.

[0004] (2) In terms of construction technology, the existing construction technology includes base surface treatment, primer application, leveling layer application and topcoat application. Generally, the formulations of primer, intermediate coat and topcoat are different and have poor versatility, which makes it difficult to manage the construction site. Moreover, if the additives in the formulation are not selected properly, interlayer adhesion problems are likely to occur. Summary of the Invention

[0005] Therefore, it is necessary to provide a two-component waterborne polyurethane wear-resistant floor coating, its application, and application method to address the above problems; the floor coating has excellent water resistance, acid resistance, and wear resistance, and can be applied to the primer layer, leveling layer, and topcoat layer simultaneously, with high versatility.

[0006] A two-component waterborne polyurethane wear-resistant floor coating, the raw materials include component A and component B. By mass fraction, component A includes 45%-65% waterborne modified hydroxy acrylic dispersion, 15%-40% micron-sized filler, 1%-10% nano-sized filler, 5%-15% waterborne color paste, less than 10% of additives, and 5%-15% water.

[0007] The waterborne modified hydroxy acrylic acid dispersion is obtained by graft copolymerization, in which organosilicon modified polyurethane segments are used as soft segments and bonded to the waterborne hydroxy acrylic acid backbone. The mass ratio of the organosilicon modified polyurethane segments to the waterborne hydroxy acrylic acid backbone is 1:1-1.5:1, and the iodine value of the waterborne modified hydroxy acrylic acid dispersion is 5-20.

[0008] Component B is an isocyanate curing agent.

[0009] In one embodiment, when the two-component waterborne polyurethane wear-resistant floor coating is used, the mass ratio of component A to component B is 3:1-8:1.

[0010] In one embodiment, the molecular weight of the silicone-modified polyurethane segment is 2000-4000.

[0011] And / or, the viscosity of the aqueous modified hydroxy acrylic dispersion is 800 mPa·s-2000 mPa·s.

[0012] In one embodiment, the micron-sized filler is selected from at least one of talc, silica powder, barium sulfate, calcium carbonate, and mica powder, and the nano-sized filler is selected from at least one of nano-calcium carbonate, nano-silica, nano-alumina, and nano-barium sulfate.

[0013] In one embodiment, the additive includes at least one of defoamer, dispersant, leveling agent, and rheology modifier.

[0014] In one embodiment, the two-component waterborne polyurethane wear-resistant floor coating, by mass fraction, comprises, in component A, 45%-65% waterborne modified hydroxyl acrylic dispersion, 0.1%-1.0% defoamer, 0.1%-1.0% dispersant, 0.1%-1.0% leveling agent, 15%-40% micron-sized filler, 1%-10% nano-sized filler, 5%-15% waterborne colorant, 0.5%-3% rheology modifier, and 5%-15% deionized water.

[0015] In one embodiment, the defoamer is selected from at least one of silicone defoamers and polymeric defoamers;

[0016] And / or, the dispersant is selected from at least one of siloxanes and styrene-maleic acid copolymers;

[0017] And / or, the leveling agent is selected from at least one of polyether siloxane and polyacrylate;

[0018] And / or, the rheology modifier is selected from at least one of "cabin-type structure" modified silicate, fumed silica, bentonite, and polyamide wax.

[0019] This invention also provides the application of two-component waterborne polyurethane wear-resistant floor coatings in primers, leveling layers and topcoats.

[0020] This invention also provides a method for applying a two-component waterborne polyurethane wear-resistant floor coating, comprising the following steps:

[0021] The A and B components of the two-component waterborne polyurethane wear-resistant floor paint are mixed and then applied to the substrate surface to form a primer layer.

[0022] The particulate filler is mixed with components A and B of the two-component waterborne polyurethane wear-resistant floor paint and applied to the surface of the primer layer to form a leveling layer.

[0023] The A and B components of the two-component waterborne polyurethane wear-resistant floor paint are mixed and then applied to the surface of the leveling layer to form a topcoat layer.

[0024] In one embodiment, in the step of mixing the particulate filler with the two-component waterborne polyurethane wear-resistant floor paint, the mass ratio of the two-component waterborne polyurethane wear-resistant floor paint to the particulate filler is 1:0.1-1:0.4, and the particulate filler is selected from quartz sand.

[0025] In the two-component waterborne polyurethane wear-resistant floor coating of the present invention, in the molecular chain structure of the waterborne modified hydroxy acrylic dispersion with a specific ratio, the main chain is mainly composed of hard segments of styrene and methyl methacrylate, which are rich in benzene rings and methyl groups, and have high mechanical strength, thus providing excellent wear resistance. The side chains are mainly composed of soft segments of polyurethane, which contain a certain amount of unsaturated fatty acids. The double bonds in these branches can slowly crosslink to increase the crosslinking density of the coating and, in conjunction with the modification effect of organosilicon, further improve the wear resistance of the resin coating.

[0026] Meanwhile, the solid content in the two-component waterborne polyurethane wear-resistant floor coating is 45%-60%, and the modified waterborne modified hydroxy acrylic dispersion can synergistically interact with the nanofillers, enabling the nanofillers to be effectively embedded in the gaps between polymer molecular chain segments, thereby further improving the density of the coating film, and thus further improving the wear resistance, water resistance and acid resistance of the coating film. Detailed Implementation

[0027] To facilitate understanding of the present invention, it will be described in more detail below. However, it should be understood that the present invention can be implemented in many different forms and is not limited to the embodiments or examples described herein. Rather, these embodiments or examples are provided to make the disclosure of the present invention more thorough and complete.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments or examples only and is not intended to be limiting of the invention.

[0029] The two-component waterborne polyurethane wear-resistant floor coating provided by the present invention comprises component A and component B. By mass fraction, component A comprises 45%-65% waterborne modified hydroxy acrylic dispersion, 15%-40% micron-sized filler, 1%-10% nano-sized filler, 5%-15% waterborne color paste, up to 10% of additives, and 5%-15% water.

[0030] The waterborne modified hydroxy acrylic acid dispersion is obtained by graft copolymerization, in which organosilicon modified polyurethane segments are bonded to the waterborne hydroxy acrylic acid backbone as soft segments, and the mass ratio of the organosilicon modified polyurethane segments to the waterborne hydroxy acrylic acid backbone is 1:1-1.5:1. The iodine value of the waterborne modified hydroxy acrylic acid dispersion is 5-20.

[0031] Component B is an isocyanate curing agent.

[0032] It should be noted that the iodine value is the number of grams of iodine that can be absorbed (added) in 100g of the substance, that is, 100g of the aqueous modified hydroxy acrylic dispersion can absorb (add) 5g-20g of iodine. Therefore, the aqueous modified hydroxy acrylic dispersion has a specific degree of unsaturation.

[0033] In the molecular chain structure of the waterborne modified hydroxy acrylic dispersion with a specific ratio, the main chain is composed of hard segments of styrene and methyl methacrylate, which are rich in benzene rings and methyl groups, resulting in high mechanical strength and thus providing excellent wear resistance for the coating. The side chains are mainly polyurethane soft segments, which provide a certain degree of flexibility for the coating. Furthermore, the polyurethane side chain structure contains a certain amount of unsaturated fatty acids, and the double bonds therein can slowly crosslink to increase the crosslinking density of the coating. In addition, the modification effect of organosilicon can further enhance the wear resistance of the resin coating.

[0034] Meanwhile, in the two-component waterborne polyurethane wear-resistant floor coating of the present invention, the solid content is 45%-60%, and the waterborne modified hydroxy acrylic dispersion can also have a synergistic effect with the nanofiller, so that the nanofiller can be effectively embedded in the gaps of the polymer molecular chain segments, thereby further improving the density of the coating film, and further improving the wear resistance, water resistance and acid resistance of the coating film.

[0035] In addition, when used in two-component waterborne polyurethane wear-resistant floor coatings, the applied external force and water evaporation during construction cause the floor coating to spread and form a film on the substrate surface. The hydroxyl functional groups in the dispersion undergo a cross-linking reaction with the isocyanate curing agent, which enables the rapid formation of polymers with larger molecular weights, thereby effectively improving the drying rate of the floor coating.

[0036] Preferably, when using the two-component waterborne polyurethane wear-resistant floor coating, the mass ratio of component A to component B is 3:1-8:1, more preferably 4:1-5:1.

[0037] Preferably, the molecular weight of the silicone-modified polyurethane segment is 2000-4000, more preferably 2000-3000, which helps to reduce the viscosity of the dispersion and make the viscosity of the water-based modified hydroxy acrylic dispersion reach 800mPa·s-2000mPa·s, which is beneficial to balancing the wear resistance of the coating.

[0038] In one embodiment, the nanoscale filler is selected from at least one of nano-calcium carbonate, nano-silica, nano-alumina, and nano-barium sulfate, and the particle size is preferably 100nm-200nm.

[0039] In one embodiment, the micron-sized filler is selected from at least one of talc, silica powder, barium sulfate, calcium carbonate, and mica powder, and the particle size is preferably 10μm-50μm.

[0040] In one embodiment, the additive includes at least one of defoamer, dispersant, leveling agent, and rheology modifier.

[0041] In one embodiment, the two-component waterborne polyurethane wear-resistant floor coating, by mass fraction, comprises, in component A, 45%-65% waterborne modified hydroxyl acrylic dispersion, 0.1%-1.0% defoamer, 0.1%-1.0% dispersant, 0.1%-1.0% leveling agent, 15%-40% micron-sized filler, 1%-10% nano-sized filler, 5%-15% waterborne colorant, 0.5%-3% rheology modifier, and 5%-15% deionized water.

[0042] Wherein, the defoamer is selected from at least one of silicone defoamers and polymeric defoamers; and / or, the dispersant is selected from at least one of siloxanes and styrene-maleic acid copolymers; and / or, the leveling agent is selected from at least one of polyether siloxanes and polyacrylates; and / or, the rheology modifier is selected from at least one of "carrot-shaped structure" silicates, fumed silica, modified bentonite, and polymeric rheology modifiers, wherein the polymeric rheology modifier includes, but is not limited to, polyamide wax.

[0043] The two-component waterborne polyurethane wear-resistant floor coating provided by this invention can be obtained by the following preparation method:

[0044] Under a protective atmosphere, the aqueous modified hydroxy acrylic dispersion, defoamer, dispersant and leveling agent are first mixed, and then micron-sized filler and nano-sized filler are added for dispersion.

[0045] After dispersion to a fineness ≤15μm, water-based colorant is added for color adjustment, and then rheology modifier and water are added to adjust the viscosity to obtain a two-component water-based polyurethane wear-resistant floor paint.

[0046] Because the two-component waterborne polyurethane abrasion-resistant floor coating of the present invention has versatility, the present invention also provides the application of the two-component waterborne polyurethane abrasion-resistant floor coating in primers, leveling layers, and topcoats. The specific application method includes the following steps:

[0047] The A and B components of the two-component waterborne polyurethane wear-resistant floor paint are mixed and then applied to the substrate surface to form a primer layer.

[0048] The particulate filler is mixed with components A and B of the two-component waterborne polyurethane wear-resistant floor paint and applied to the surface of the primer layer to form a leveling layer.

[0049] The A and B components of the two-component waterborne polyurethane wear-resistant floor paint are mixed and then applied to the surface of the leveling layer to form a topcoat layer.

[0050] In one embodiment, before applying the two-component waterborne polyurethane wear-resistant floor paint to the substrate surface to form a primer layer, the substrate surface can be pretreated, such as by removing surface particulate residues or other conventional operations.

[0051] In one embodiment, in the step of mixing the particulate filler with the two-component waterborne polyurethane wear-resistant floor paint, the mass ratio of the two-component waterborne polyurethane wear-resistant floor paint to the particulate filler is 1:0.1-1:0.4, and the particulate filler is selected from quartz sand, preferably quartz sand of different particle sizes for compounding.

[0052] Optionally, both the primer and topcoat layers can be applied by roller or spray, while the leveling layer can be applied by scraping with a notched trowel.

[0053] The following specific embodiments will further illustrate the two-component waterborne polyurethane wear-resistant floor coating, its application, and application methods.

[0054] Example 1

[0055] Under nitrogen purging, 3 parts by weight of xylene, 3 parts by weight of trimethylolpropane, 10 parts by weight of tung oil acid, and 1 part by weight of phthalic anhydride were placed in a four-necked flask equipped with a reflux condenser, stirrer, and thermometer. The mixture was heated to 220°C and maintained at this temperature. When the acid value of the system was ≤3 mg KOH / g, the system temperature was lowered to 80°C, and 3 parts by weight of toluene diisocyanate and 5 parts by weight of hydroxyl silicone oil were added dropwise over 1 hour. The mixture was then maintained at this temperature for 1 hour. The temperature was then increased... At 120°C, 8 parts by weight of methyl methacrylate, 5 parts by weight of styrene, 5 parts by weight of hydroxyethyl methacrylate, 5 parts by weight of acrylic acid and 1 part by weight of tert-butyl benzoate were mixed and added dropwise over 3 hours. After the addition was complete, the mixture was kept at this temperature for 3 hours. After cooling to room temperature, 5 parts by weight of N,N-dimethylethanolamine were added dropwise and dispersed for 0.5 hours. Then, 46 parts by weight of deionized water were added and dispersed for 0.5 hours to obtain the water-based modified hydroxy acrylic acid dispersion.

[0056] 55 parts by weight of aqueous hydroxy acrylic acid dispersion, 0.5 parts by weight of BYK1785, 0.5 parts by weight of Tegoairex901W, 0.7 parts by weight of Tegodisper656, 0.3 parts by weight of BYK2018, and 0.8 parts by weight of TegoTwin4100 were sequentially added to a reactor equipped with a jacketed cooling device. The mixture was stirred at 600 rpm for 15 minutes. Then, under continuous stirring, 10 parts by weight of 2000-mesh talc powder, 10 parts by weight of 1250-mesh silica powder, and 5 parts by weight of nano-calcium carbonate M2 were added sequentially, and the stirring speed was increased to 5000 rpm for high-speed dispersion. During this process, the temperature inside the reactor was monitored and controlled at 50±5℃. The jacketed cooling device was turned on if necessary.

[0057] After dispersion for 1 hour, the fineness was tested every 10 minutes until the fineness was ≤15μm. Then, the stirring speed was reduced to 500rpm, 8 parts by weight of water-based color paste (gray) was added to adjust the color, and stirring was continued for 15 minutes. Then, 1.2 parts by weight of Rheolate 350D and 8 parts by weight of deionized water were added to adjust the viscosity. The stirring speed was maintained at 500rpm and stirred for 10 minutes before stopping, thus obtaining component A of the two-component water-based polyurethane wear-resistant floor paint.

[0058] Using standard laboratory-grade cement fiberboard as the substrate, surface particulate residues were first removed. Component A (4:1 mass ratio) was then mixed with an isocyanate-based curing agent (Bayer 2655) and applied as a primer by roller onto the standard cement fiberboard at a rate of 0.15 kg / m². 2 After 20 minutes, mix component A (4:1 mass ratio) with isocyanate curing agent (Bayer 2655), then mix with 80-120 mesh quartz sand at a mass ratio of 1:0.3. Apply the mixture as a leveling layer using a notched trowel, at a rate of 0.6 kg / m². 2 After 4 hours, component A (by mass ratio 4:1) is mixed with isocyanate curing agent (Bayer 2655) and applied as a topcoat to the leveling layer by roller, at a rate of 0.2 kg / m². 2 .

[0059] Example 2

[0060] Aqueous modified hydroxy acrylic acid dispersions were prepared using the same preparation method as in Example 1.

[0061] The difference between Example 2 and Example 1 is that 5 parts by weight of 1250 mesh molybdenum disulfide powder are used instead of 5 parts by weight of 1250 mesh silica powder, and the mass ratio of component A to isocyanate curing agent is 5:1.

[0062] Example 3

[0063] Three parts by weight of xylene, three parts by weight of trimethylolpropane, 12 parts by weight of soybean oil, and one part by weight of phthalic anhydride were placed in a four-necked flask equipped with a reflux condenser, stirrer, and thermometer. The mixture was heated to 220°C and maintained at this temperature. When the acid value of the system was ≤3 mg KOH / g, the temperature was lowered to 80°C, and three parts by weight of toluene diisocyanate and five parts by weight of hydroxyl silicone oil were added dropwise over 1 hour. The mixture was then maintained at this temperature for 1 hour. The temperature was then raised to 120°C. At ℃, 6 parts by weight of methyl methacrylate, 5 parts by weight of styrene, 5 parts by weight of hydroxyethyl methacrylate, 5 parts by weight of acrylic acid and 1 part by weight of tert-butyl benzoate were mixed and added dropwise over 3 hours. After the addition was complete, the mixture was kept at the same temperature for 3 hours. After cooling to room temperature, 5 parts by weight of N,N-dimethylethanolamine were added dropwise and dispersed for 0.5 hours. Then, 46 parts by weight of deionized water were added and dispersed for 0.5 hours to obtain the water-based modified hydroxy acrylic acid dispersion.

[0064] 45 parts by weight of aqueous hydroxy acrylic acid dispersion, 0.5 parts by weight of VOK2502, 0.5 parts by weight of Tegoairex901W, 1.7 parts by weight of TEGO-760W, 1.3 parts by weight of BYK2018, and 0.8 parts by weight of TegoTwin4100 were sequentially added to a reactor equipped with a jacketed cooling device. The mixture was stirred at 600 rpm for 15 minutes. Then, under continuous stirring, 14 parts by weight of 2000-mesh talc powder, 14 parts by weight of 1250-mesh silica powder, and 5 parts by weight of nano-calcium carbonate M2 were added sequentially, and the stirring speed was increased to 5000 rpm for high-speed dispersion. During this process, the temperature inside the reactor was monitored and controlled at 50±5℃. The jacketed cooling device was turned on if necessary.

[0065] After dispersion for 1 hour, the fineness was tested every 10 minutes until the fineness was ≤15μm. Then, the stirring speed was reduced to 500rpm, 8 parts by weight of water-based color paste (gray) was added to adjust the color, and stirring was continued for 15 minutes. Then, 1.2 parts by weight of Rheolate 350D and 8 parts by weight of deionized water were added to adjust the viscosity. The stirring speed was maintained at 500rpm and stirred for 10 minutes before stopping, thus obtaining component A of the two-component water-based polyurethane wear-resistant floor paint.

[0066] Using the same method as in Example 1, component A and isocyanate curing agent were combined to form a two-component waterborne polyurethane wear-resistant floor coating for use as primer, leveling layer and topcoat.

[0067] Example 4

[0068] Three parts by weight of xylene, three parts by weight of trimethylolpropane, 15 parts by weight of ricinoleic acid, and one part by weight of phthalic anhydride were placed in a four-necked flask equipped with a reflux condenser, stirrer, and thermometer. The mixture was heated to 220°C and maintained at this temperature. When the acid value of the system was ≤3 mg KOH / g, the temperature was lowered to 80°C, and three parts by weight of toluene diisocyanate and five parts by weight of hydroxyl silicone oil were added dropwise over 1 hour. The mixture was then maintained at this temperature for 1 hour. The temperature was then raised to 120°C. At 0℃, 3 parts by weight of methyl methacrylate, 5 parts by weight of styrene, 5 parts by weight of hydroxyethyl methacrylate, 5 parts by weight of acrylic acid and 1 part by weight of tert-butyl benzoate were mixed and added dropwise over 3 hours. After the addition was complete, the mixture was kept at this temperature for 3 hours. After cooling to room temperature, 5 parts by weight of N,N-dimethylethanolamine were added dropwise and dispersed for 0.5 hours. Then, 46 parts by weight of deionized water were added and dispersed for 0.5 hours to obtain the water-based modified hydroxy acrylic acid dispersion.

[0069] 65 parts by weight of aqueous hydroxy acrylic acid dispersion, 1 part by weight of VOK2502, 0.7 parts by weight of TEGO-760W, 0.3 parts by weight of BYK2018, and 0.8 parts by weight of TegoTwin4100 were sequentially added to a reactor equipped with a jacketed cooling device. The mixture was stirred at 600 rpm for 15 minutes. Then, under continuous stirring, 8 parts by weight of 2000-mesh talc powder, 7 parts by weight of 1250-mesh silica powder, and 2 parts by weight of nano-calcium carbonate M2 were sequentially added, and the stirring speed was increased to 5000 rpm for high-speed dispersion. During this process, the temperature inside the reactor was monitored and controlled at 50±5℃. The jacketed cooling device was turned on if necessary.

[0070] After dispersion for 1 hour, the fineness was tested every 10 minutes until the fineness was ≤15μm. Then, the stirring speed was reduced to 500rpm, 6 parts by weight of water-based color paste (gray) was added to adjust the color, and stirring was continued for 15 minutes. Then, 1.2 parts by weight of Rheolate 350D and 8 parts by weight of deionized water were added to adjust the viscosity. The stirring speed was maintained at 500rpm and stirred for 10 minutes before stopping, thus obtaining component A of the two-component water-based polyurethane wear-resistant floor paint.

[0071] Using the same method as in Example 1, component A and isocyanate curing agent were combined to form a two-component waterborne polyurethane wear-resistant floor coating for use as primer, leveling layer and topcoat.

[0072] Comparative Example 1

[0073] The difference between Comparative Example 1 and Example 1 is that, under nitrogen purging, 5 parts by weight of propylene glycol methyl ether were placed in a four-necked flask equipped with a reflux condenser, stirrer, and thermometer, and the temperature was slowly increased; 13 parts by weight of methyl methacrylate, 11 parts by weight of styrene, 5 parts by weight of butyl acrylate, 8 parts by weight of hydroxyethyl methacrylate, 5 parts by weight of acrylic acid, and 1.5 parts by weight of tert-butyl peroxide were mixed and placed in a constant pressure dropping funnel. When the temperature of the four-necked flask reached 130°C, the mixture was added dropwise over 3 hours. After the addition was complete, the mixture was kept at this temperature for 3 hours. After cooling to room temperature, 5 parts by weight of N,N-dimethylethanolamine were added dropwise and dispersed for 0.5 hours. Then, 46.5 parts by weight of deionized water were added and dispersed for 0.5 hours to obtain an aqueous hydroxyacrylic acid dispersion.

[0074] Comparative Example 2

[0075] The difference between Comparative Example 2 and Example 1 is that, under nitrogen purging, 3 parts by weight of xylene, 5 parts by weight of trimethylolpropane, 10 parts by weight of tung oil acid, and 1 part by weight of phthalic anhydride were placed in a four-necked flask equipped with a reflux condenser, stirrer, and thermometer, and the temperature was raised to 220°C and maintained for reaction. When the acid value of the system was ≤3 mg KOH / g, the system temperature was lowered to 80°C, and 3 parts by weight of toluene diisocyanate were added dropwise over 1 hour, followed by 1 hour of maintaining the temperature for reaction. The mixture was heated to 120°C, and 8 parts by weight of methyl methacrylate, 5 parts by weight of styrene, 8 parts by weight of hydroxyethyl methacrylate, 5 parts by weight of acrylic acid and 1 part by weight of tert-butyl benzoate were mixed. The mixture was added dropwise over 3 hours. After the addition was complete, the mixture was kept at this temperature for 3 hours. After cooling to room temperature, 5 parts by weight of N,N-dimethylethanolamine were added dropwise. The mixture was dispersed for 0.5 hours, and then 46 parts by weight of deionized water were added and dispersed for 0.5 hours to obtain the waterborne polyurethane modified hydroxypropyl dispersion.

[0076] Comparative Example 3

[0077] The difference between Comparative Example 3 and Example 1 is that the amount of tung oil acid was increased to 16 parts by weight, and the amount of methyl methacrylate was reduced to 3 parts by weight.

[0078] Comparative Example 4

[0079] The difference between Comparative Example 4 and Example 1 is that the amount of tung oil acid was reduced to 2 parts by weight, and the amount of methyl methacrylate was increased to 13 parts by weight.

[0080] The mass ratio of soft and hard monomers and the content of unsaturated bonds in the water-based modified hydroxy acrylic dispersions prepared in Examples 1, 3-4 and Comparative Examples 3-4 were adjusted by designing and adjusting the types and quantities of reactants. The molecular weight of the organosilicon-modified polyurethane segments was detected by gel permeation chromatography, and the viscosity of the dispersion was detected by rotational viscometer. The results are shown in Table 1.

[0081] Table 1

[0082]

[0083] Key performance tests were conducted on the floor coatings of Examples 1-4 and Comparative Examples 1-4, and the results are shown in Table 2.

[0084] Test environment conditions: temperature 23±2℃, relative humidity 50±5%. Abrasion resistance, acid resistance, and water resistance tests were conducted after the film was cured for 7 days under these conditions. Specific test methods are as follows:

[0085] The drying time (including surface drying time and actual drying time) shall be tested in accordance with GB / T1728-1979. The surface drying time shall be determined according to Method B, and the actual drying time shall be determined according to Method A.

[0086] Wear resistance is tested according to GB / T1768, using a CS-17 rubber grinding wheel with a load of 750g and a rotation speed of 500 rpm;

[0087] Pencil hardness was determined according to GB / T6739-2006 standard;

[0088] Water resistance and acid resistance were tested according to the drop test method in GB / T9724-1988, where the water was grade III water conforming to GB / T6682, the test period was 7 days, and the acid was a 10% sulfuric acid solution, the test period was 48 hours.

[0089] Freeze-thaw stability was determined according to method GB-T9268-2008A;

[0090] The thermal storage stability test conditions were 50℃ and 75RPM. The upper layer stratification and the precipitation of pigments and fillers at the bottom of the sample were observed every 7 days.

[0091] Table 2

[0092]

[0093] As shown in Table 1, the main film-forming substance in Examples 1-4 is a silicone-polyurethane modified waterborne hydroxy acrylic dispersion, and the resulting two-component waterborne polyurethane floor coating exhibits excellent water resistance, acid resistance, and abrasion resistance. In contrast, the main film-forming substance in Comparative Example 1 is a waterborne hydroxy acrylic dispersion with a high content of hard segments, resulting in poor water and acid resistance in the resulting two-component waterborne polyurethane floor coating. In Comparative Example 2, the main film-forming substance is a polyurethane soft segment modified waterborne hydroxy acrylic dispersion, where the soft segments are not modified with silicone, resulting in poor abrasion resistance in the resulting two-component waterborne polyurethane floor coating. In Comparative Example 3, the mass ratio of soft to hard monomers is 2:1. Due to the higher content of soft segments, the surface drying and complete drying times are prolonged, leading to a decrease in coating abrasion resistance. In Comparative Example 4, the soft segment content is further increased, resulting in a decrease in the glass transition temperature of the dispersion, prolonged surface drying and complete drying times, and a decrease in coating abrasion resistance.

[0094] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0095] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A two-component waterborne polyurethane wear-resistant floor coating, characterized in that, The raw materials of the two-component waterborne polyurethane wear-resistant floor coating include component A and component B. By mass fraction, component A includes 45%-65% waterborne modified hydroxy acrylic dispersion, 15%-40% micron-sized filler, 1%-10% nano-sized filler, 5%-15% waterborne color paste, less than 10% of additives, and 5%-15% water. The waterborne modified hydroxy acrylic acid dispersion is obtained by graft copolymerization, in which organosilicon modified polyurethane segments are bonded to the waterborne hydroxy acrylic acid backbone as soft segments, and the mass ratio of the organosilicon modified polyurethane segments to the waterborne hydroxy acrylic acid backbone is 1:1-1.5:

1. The iodine value of the waterborne modified hydroxy acrylic acid dispersion is 5-20, and the backbone is mainly composed of hard segments of styrene and methyl methacrylate. The method for preparing the waterborne modified hydroxy acrylic acid dispersion includes: subjecting trimethylolpropane, unsaturated fatty acids, and phthalic anhydride to a heat-preserving reaction; when the acid value of the system is ≤3mgKOH / g, cooling the system temperature; adding toluene diisocyanate and hydroxyl silicone oil to a heat-preserving reaction; then heating up and adding methyl methacrylate, styrene, hydroxyethyl methacrylate, and acrylic acid to carry out free radical polymerization to obtain the waterborne modified hydroxy acrylic acid dispersion. Component B is an isocyanate curing agent.

2. The two-component waterborne polyurethane wear-resistant floor coating according to claim 1, characterized in that, When using the two-component waterborne polyurethane wear-resistant floor coating, the mass ratio of component A to component B is 3:1-8:

1.

3. The two-component waterborne polyurethane wear-resistant floor coating according to claim 1, characterized in that, The organosilicon-modified polyurethane segment has a molecular weight of 2000-4000. And / or, the viscosity of the aqueous modified hydroxy acrylic dispersion is 800 mPa·s-2000 mPa·s.

4. The two-component waterborne polyurethane wear-resistant floor coating according to claim 1, characterized in that, The micron-sized filler is selected from at least one of talc powder, silica powder, barium sulfate, calcium carbonate, and mica powder, and the nano-sized filler is selected from at least one of nano-calcium carbonate, nano-silica, nano-alumina, and nano-barium sulfate.

5. The two-component waterborne polyurethane wear-resistant floor coating according to claim 1, characterized in that, The additives include at least one of defoamers, dispersants, leveling agents, and rheology modifiers.

6. The two-component waterborne polyurethane wear-resistant floor coating according to any one of claims 1-5, characterized in that, By mass fraction, component A comprises 45%-65% aqueous modified hydroxy acrylic dispersion, 0.1%-1.0% defoamer, 0.1%-1.0% dispersant, 0.1%-1.0% leveling agent, 15%-40% micron-sized filler, 1%-10% nano-sized filler, 5%-15% aqueous color paste, 0.5%-3% rheology modifier, and 5%-15% deionized water.

7. The two-component waterborne polyurethane wear-resistant floor coating according to claim 6, characterized in that, The defoamer is selected from polymer-type defoamers; And / or, the dispersant is selected from at least one of siloxanes and styrene-maleic acid copolymers; And / or, the leveling agent is selected from at least one of polyether siloxane and polyacrylate; And / or, the rheology modifier is selected from at least one of "carrot-type structure" silicates, fumed silica, bentonite, and polyamide wax.

8. The two-component waterborne polyurethane wear-resistant floor coating according to claim 7, characterized in that, The defoamer is selected from silicone defoamers.

9. The application of a two-component waterborne polyurethane wear-resistant floor coating as described in any one of claims 1-8 in a primer, leveling layer, and topcoat.

10. A method for applying the two-component waterborne polyurethane wear-resistant floor coating as described in any one of claims 9, characterized in that, Includes the following steps: The A and B components of the two-component waterborne polyurethane wear-resistant floor paint are mixed and then applied to the substrate surface to form a primer layer. The particulate filler is mixed with components A and B of the two-component waterborne polyurethane wear-resistant floor paint and applied to the surface of the primer layer to form a leveling layer. The A and B components of the two-component waterborne polyurethane wear-resistant floor paint are mixed and then applied to the surface of the leveling layer to form a topcoat layer.

11. The application method of the two-component waterborne polyurethane wear-resistant floor coating according to claim 10, characterized in that, In the step of mixing the particulate filler with the two-component waterborne polyurethane wear-resistant floor paint, the mass ratio of the two-component waterborne polyurethane wear-resistant floor paint to the particulate filler is 1:0.1-1:0.4, and the particulate filler is selected from quartz sand.

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