Preparation process and application of an antibacterial and antifouling environmentally friendly water-based coating

Abstract

The present invention provides a preparation process and application of an antibacterial and antifouling environmentally friendly water-based coating, comprising the following steps: (1) preparing a polyurethane resin; (2) mixing 37-42 parts by mass of a polyurethane resin, 14-19 parts by mass of an epoxy resin, 5-8 parts by mass of a modified shell powder, 1-2 parts by mass of a thickener, 0.3-0.8 parts by mass of a leveling agent, 1-2 parts by mass of a film-forming aid and 20-25 parts by mass of deionized water to obtain an environmentally friendly water-based coating. The environmentally friendly water-based coating prepared by the present invention has a strong adhesion to a PVC board, a high hardness of a paint film, good wear resistance, antibacterial and antifouling properties, and high storage stability. In addition, the water-based coating provided by the present invention is greener and more environmentally friendly, and has a broad market prospect.

Description

Technical Field

[0001] This invention belongs to the field of coating technology, specifically relating to the preparation process and application of an antibacterial and antifouling environmentally friendly water-based coating. Background Art

[0002] PVC is widely used for decorative furniture coverings, as it offers a variety of colors and textures, such as wood, stone, and other designs, enhancing the aesthetic appeal of furniture and adapting it to various decorative styles. PVC surfaces are often also coated with paint, primarily for stain and friction resistance. Traditional PVC surface coatings contain large amounts of organic solvents, which are environmentally unfriendly and harmful to the human body. Water-based paints are polymer materials that use water as a dispersion medium, replacing the organic solvents found in traditional paints. They offer advantages such as being non-toxic, pollution-free, non-flammable, non-explosive, and low cost. However, there are some problems with the current water-based coatings used on PVC surfaces in practical applications: (1) Adhesion problems: Since the surface of PVC is smooth and non-polar, it may be difficult for water-based coatings to form good adhesion on it, which may cause the coating to peel or fall off; (2) Mechanical resistance: The coating formed by water-based coatings on the PVC surface may not be as hard as solvent-based coatings, and has weaker resistance to mechanical wear and tear, and is prone to scratches or wear during use; (3) Antibacterial and anti-fouling properties: When furniture is used in daily life, it is often inadvertently left with marks by writing tools such as markers, especially in families with children. Water-based coatings have poor resistance to marker graffiti, making it difficult to keep the furniture surface clean, and the antibacterial effect is not ideal.

[0003] Therefore, developing an environmentally friendly water-based coating that is antibacterial, stain-resistant, and has excellent mechanical properties has extremely high market value and broad application prospects. Summary of the Invention

[0004] The purpose of this invention is to provide a preparation process and application of an antibacterial and antifouling environmentally friendly water-based coating.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A preparation process for an antibacterial and antifouling environmentally friendly water-based coating includes the following steps:

[0007] (1) Weigh 3-4 parts by weight of hexamethylene diisocyanate, 1-2 parts by weight of polyethylene glycol 300, and 6-9 parts by weight of butanone, mix them evenly, heat to 60-65℃, keep warm for 2-3 hours, continue to add 4-5 parts by weight of polyether polyol and 0.3-0.6 parts by weight of stannous octoate, react at 80-85℃ for 3-4 hours, cool down to 40-50℃, continue to add 2-3 parts by weight of 1,4-butanediol and 1-1.5 parts by weight of triethylamine, mix evenly, heat to 70-75℃, keep warm for 4-5 hours, cool to room temperature to obtain polyurethane resin;

[0008] (2) Mix 37-42 parts by weight of polyurethane resin, 14-19 parts by weight of epoxy resin, 5-8 parts by weight of modified shell powder, 1-2 parts by weight of thickener, 0.3-0.8 parts by weight of leveling agent, 1-2 parts by weight of film-forming aid and 20-25 parts by weight of deionized water evenly to obtain an environmentally friendly water-based coating.

[0009] Furthermore, the polyether polyol is a compound of polyether triol with 535 mg KOH / g of hydroxyl groups, polyether diol with 36-39 mg KOH / g of hydroxyl groups, and polyether diol with 153-188 mg KOH / g of hydroxyl groups in a mass ratio of 1:0.2-0.5:1.5-1.8.

[0010] Polyether triol with hydroxyl count of 535 mg KOH / g, Arkema, France, model TO330. Polyether diol with hydroxyl count of 36-39 mg KOH / g, Xuzhou Yihuiyang New Material Co., Ltd., DL-3000D. Polyether diol with hydroxyl count of 153-188 mg KOH / g, Jining Tangyi Chemical Co., Ltd., HSH-310.

[0011] Further, the epoxy resin is an epoxy resin with an epoxy equivalent of 210-230 g / mol, an epoxy equivalent of 176-184 g / mol, or an epoxy equivalent of 184-195 g / mol, with a mass ratio of 1:1.3-1.5:0.4-0.7.

[0012] Epoxy resin with an epoxy equivalent of 210-230 g / mol, Phoenix brand WSR 6101 epoxy resin.

[0013] Epoxy resin with an epoxy equivalent of 176-184 g / mol, Phoenix brand E54 epoxy resin.

[0014] Epoxy resin with epoxy equivalent weight of 184-195g / mol, Phoenix brand WSR 618 epoxy resin.

[0015] The application of wear-resistant coatings on the PVC covering of furniture surface decoration is an indispensable part of furniture manufacturing and maintenance. It ensures that the furniture is not only visually pleasing, but also durable in actual use, and is a part of quality assurance. Polyurethane coatings have better wear resistance than other types of coatings and are often called "wear-resistant rubber". However, since furniture is a necessity in daily life and is frequently touched and used every day, the appearance of furniture directly affects the overall effect of interior decoration and the mood of the occupants. Better wear resistance is required for the coating, which can also extend the service life of the furniture. Existing commercially available polyurethane coatings cannot meet the above requirements. The present invention improves the wear resistance of water-based coatings by compounding homemade polyurethane with epoxy resin. Analysis shows that polyurethane and epoxy resin can form a more complex network structure and improve the cross-linking density. At the same time, the inventors found that the hardness of water-based coatings is improved under this condition.

[0016] Furthermore, the preparation method of the modified shell powder is:

[0017] (1) uniformly mixing 20-25 parts by mass of polyacrylate emulsion, 5-7 parts by mass of shell powder, and 100 parts by mass of water, and performing ultrasonic dispersion treatment to obtain a mixture;

[0018] (2) Stir the mixture and heat it to 93℃-95℃, keep it at the temperature for 3-4 hours to obtain the reaction product;

[0019] (3) The reaction product is filtered, the filter cake is washed with deionized water, dried at 170°C-175°C for 50-60 minutes, and crushed to obtain modified shell powder.

[0020] Furthermore, the ultrasonic dispersion treatment is carried out under the conditions of 35-40 kHz for 15-20 min.

[0021] Furthermore, the polyacrylate emulsion is polyacrylate emulsion model LA6588 produced by Shandong Liang New Material Technology Co., Ltd.

[0022] Furthermore, the shell powder is composed of shell powders of three different particle size ranges, specifically: the mass ratio of shell powders with particle sizes of 50-200 mesh, 400-600 mesh, and 1800-2000 mesh is 1.3-1.5:1:0.4-0.6.

[0023] Shell powder, derived from natural seashells, is processed through high-temperature calcination and fine grinding, and is a material containing natural anti-mildew substances. When shell powder is added to the water-based coating system of this invention, the adhesion of the water-based coating is unsatisfactory, failing to adhere well to PVC substrates. This invention improves the adhesion of the water-based coating to PVC by modifying the shell powder. Analysis shows that the modified shell powder has better compatibility with the components in the system of this invention. Simultaneously, the inventors found that adding modified shell powder also improves the storage stability of the water-based coating. Furthermore, when using shell powder with three different particle size ranges for modification, the anti-mildew properties of the water-based coating can be enhanced. Analysis shows that under these conditions, the compounded shell powder can adjust the surface area for bacterial contact and form a more complex pore structure, which helps to adsorb and capture more bacteria, thereby improving antibacterial efficiency. Under these conditions, the antifouling properties of the water-based coating can also be improved.

[0024] Furthermore, the film-forming aid is dipropylene glycol methyl ether. CAS Registry Number 34590-94-8.

[0025] Furthermore, the leveling agent is a polyurethane rheology modifier. Beijing Dongfang Chennuo Chemical Technology Co., Ltd., model CN-2020.

[0026] Furthermore, the thickener is a solvent-free polyurethane thickener. Specifically, it is Coatex polyurethane thickener from France, model Coapur XS83.

[0027] This invention provides the application of an antibacterial and antifouling environmentally friendly water-based coating prepared by the aforementioned process, wherein the water-based coating is used for spraying onto the surface of furniture decorated with PVC.

[0028] Compared with the prior art, the advantages and beneficial effects of the present invention are:

[0029] 1. The environmentally friendly water-based coating prepared by this invention has strong adhesion to PVC boards, high film hardness, good wear resistance, antibacterial and anti-fouling properties, and high storage stability. Furthermore, the water-based coating provided by this invention is greener and more environmentally friendly, and has broad market prospects.

[0030] 2. This invention improves the abrasion resistance of water-based coatings by compounding a self-made polyurethane with epoxy resin. Analysis shows that polyurethane and epoxy resin can form a more complex network structure, improving the crosslinking density. Simultaneously, the inventors discovered that this condition also improves the hardness of the water-based coating.

[0031] 3. This invention improves the adhesion of water-based coatings to PVC by modifying shell powder. The inventors also discovered that adding modified shell powder improves the storage stability of water-based coatings.

[0032] 4. When shell powder with three different particle size ranges is used for modification, the anti-fungal property of water-based paint can be improved. At the same time, the anti-fouling property of water-based paint can be improved. DETAILED DESCRIPTION

[0033] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0034] Example 1

[0035] This embodiment provides a preparation process for an antibacterial and antifouling environmentally friendly water-based coating, comprising the following steps:

[0036] (1) Weigh 3.5 parts by weight of hexamethylene diisocyanate, 1.4 parts by weight of polyethylene glycol 300 and 8 parts by weight of butanone, mix them evenly, heat to 63°C, keep warm for 2.5h, then add 4.6 parts by weight of polyether polyol and 0.5 parts by weight of stannous octoate, react at 82°C for 3.5h, cool down to 45°C, then add 2.6 parts by weight of 1,4-butanediol and 1.2 parts by weight of triethylamine, mix evenly, heat to 72°C, keep warm for 4.5h, cool to room temperature to obtain polyurethane resin;

[0037] (2) 40 parts by mass of polyurethane resin, 16 parts by mass of epoxy resin, 7 parts by mass of modified shell powder, 1.5 parts by mass of thickener, 0.5 parts by mass of leveling agent, 1.5 parts by mass of film-forming aid and 22 parts by mass of deionized water are mixed uniformly to obtain an environmentally friendly water-based paint.

[0038] The polyether polyol is a polyether triol with a hydroxyl number of 535 mgKOH / g, a polyether diol with a hydroxyl number of 36-39 mgKOH / g, and a polyether diol with a hydroxyl number of 153-188 mgKOH / g, which are compounded in a mass ratio of 1:0.4:1.7.

[0039] Polyether triol with a hydroxyl number of 535 mgKOH / g, Arkema, France, model TO330. Polyether diol with a hydroxyl number of 36-39 mgKOH / g, Xuzhou Yihuiyang New Materials Co., Ltd., DL-3000D. Polyether diol with a hydroxyl number of 153-188 mgKOH / g, Jining Tangyi Chemical Co., Ltd., HSH-310.

[0040] The epoxy resins are epoxy resins with an epoxy equivalent of 210-230 g / mol, epoxy resins with an epoxy equivalent of 176-184 g / mol, and epoxy resins with an epoxy equivalent of 184-195 g / mol, with a mass ratio of 1:1.4:0.6.

[0041] Epoxy resin with an epoxy equivalent of 210-230 g / mol, Phoenix brand WSR 6101 epoxy resin.

[0042] Epoxy resin with an epoxy equivalent of 176-184 g / mol, Phoenix brand E54 epoxy resin.

[0043] Phoenix brand WSR 618 epoxy resin has an epoxy equivalent of 184-195 g / mol.

[0044] The preparation method of modified shell powder is as follows:

[0045] (1) Mix 23 parts by weight of polyacrylate emulsion, 8 parts by weight of shell powder and 100 parts by weight of water evenly, and then ultrasonically disperse the mixture to obtain a mixture.

[0046] (2) Stir the mixture and heat it to 94°C, keep it at that temperature for 3.5 h to obtain the reaction product;

[0047] (3) The reaction product was filtered, the filter cake was washed with deionized water, dried at 172℃ for 55 min, and then pulverized to obtain modified shell powder.

[0048] The conditions for ultrasonic dispersion were: ultrasonic dispersion at 38 kHz for 18 min.

[0049] The polyacrylate emulsion is model LA6588 from Shandong Li'ang New Material Technology Co., Ltd.

[0050] The shell powder is composed of three different particle size ranges of shell powder, specifically: the mass ratio of shell powder with a particle size of 50-200 mesh, 400-600 mesh, and 1800-2000 mesh is 1.4:1:0.5.

[0051] The film-forming aid is dipropylene glycol methyl ether. CAS Registry Number 34590-94-8.

[0052] The leveling agent is a polyurethane rheology modifier. Beijing Dongfang Chennuo Chemical Technology Co., Ltd., model CN-2020.

[0053] The thickener is a solvent-free polyurethane thickener. It is Coatex polyurethane thickener from France, model Coapur XS83.

[0054] Example 2

[0055] This embodiment provides a preparation process for an antibacterial and antifouling environmentally friendly water-based coating, comprising the following steps:

[0056] (1) Weigh 3 parts by mass of hexamethylene diisocyanate, 2 parts by mass of polyethylene glycol 300 and 6 parts by mass of butanone, mix them evenly, heat to 65°C and keep warm for 2 hours, then add 5 parts by mass of polyether polyol and 0.3 parts by mass of stannous octoate, react at 85°C for 3 hours, cool to 50°C, then add 2 parts by mass of 1,4-butanediol and 1.5 parts by mass of triethylamine and mix evenly, heat to 75°C and keep warm for 4 hours, then cool to room temperature to obtain polyurethane resin;

[0057] (2) 42 parts by mass of polyurethane resin, 14 parts by mass of epoxy resin, 8 parts by mass of modified shell powder, 1 part by mass of thickener, 0.8 parts by mass of leveling agent, 1 part by mass of film-forming aid and 25 parts by mass of deionized water are mixed uniformly to obtain an environmentally friendly water-based paint.

[0058] The polyether polyol is a polyether triol with a hydroxyl number of 535 mgKOH / g, a polyether diol with a hydroxyl number of 36-39 mgKOH / g, and a polyether diol with a hydroxyl number of 153-188 mgKOH / g, which are compounded in a mass ratio of 1:0.2:1.8.

[0059] Polyether triol with a hydroxyl number of 535 mgKOH / g, Arkema, France, model TO330. Polyether diol with a hydroxyl number of 36-39 mgKOH / g, Xuzhou Yihuiyang New Materials Co., Ltd., DL-3000D. Polyether diol with a hydroxyl number of 153-188 mgKOH / g, Jining Tangyi Chemical Co., Ltd., HSH-310.

[0060] The epoxy resins are epoxy resins with an epoxy equivalent weight of 210-230 g / mol, epoxy resins with an epoxy equivalent weight of 176-184 g / mol, and epoxy resins with an epoxy equivalent weight of 184-195 g / mol, with a mass ratio of 1:1.3:0.7.

[0061] Epoxy resin with an epoxy equivalent of 210-230 g / mol, Phoenix brand WSR 6101 epoxy resin.

[0062] Epoxy resin with an epoxy equivalent of 176-184 g / mol, Phoenix brand E54 epoxy resin.

[0063] Phoenix brand WSR 618 epoxy resin has an epoxy equivalent of 184-195 g / mol.

[0064] The preparation method of modified shell powder is as follows:

[0065] (1) 20 parts by mass of polyacrylate emulsion, 7 parts by mass of shell powder, and 100 parts by mass of water were mixed uniformly, and ultrasonically dispersed to obtain a mixture;

[0066] (2) stirring the mixture and heating it to 93°C for 4 hours to obtain a reaction product;

[0067] (3) The reaction product was filtered, the filter cake was washed with deionized water, dried at 170° C. for 50 min, and crushed to obtain modified shell powder.

[0068] The ultrasonic dispersion treatment conditions were as follows: ultrasonic dispersion at 35 kHz for 15 min.

[0069] The polyacrylate emulsion is model LA6588 from Shandong Li'ang New Material Technology Co., Ltd.

[0070] The shell powder is composed of three different particle size ranges of shell powder, specifically: the mass ratio of shell powder with a particle size of 50-200 mesh, 400-600 mesh, and 1800-2000 mesh is 1.3:1:0.6.

[0071] The film-forming aid is dipropylene glycol methyl ether. CAS Registry Number 34590-94-8.

[0072] The leveling agent is a polyurethane rheology modifier. Beijing Dongfang Chennuo Chemical Technology Co., Ltd., model CN-2020.

[0073] The thickener is a solvent-free polyurethane thickener. It is Coatex polyurethane thickener from France, model Coapur XS83.

[0074] Example 3

[0075] This embodiment provides a preparation process for an antibacterial and antifouling environmentally friendly water-based coating, comprising the following steps:

[0076] (1) Weigh 4 parts by mass of hexamethylene diisocyanate, 1 part by mass of polyethylene glycol 300, and 6 parts by mass of butanone, mix them evenly, heat them to 60°C, keep them warm for 3 hours, continue to add 4 parts by mass of polyether polyol and 0.6 parts by mass of stannous octoate, react at 80°C for 4 hours, cool them to 40°C, continue to add 3 parts by mass of 1,4-butanediol and 1 part by mass of triethylamine, mix them evenly, heat them to 70°C, keep them warm for 5 hours, and cool them to room temperature to obtain a polyurethane resin;

[0077] (2) 37 parts by mass of polyurethane resin, 19 parts by mass of epoxy resin, 5 parts by mass of modified shell powder, 2 parts by mass of thickener, 0.3 parts by mass of leveling agent, 2 parts by mass of film-forming aid and 20 parts by mass of deionized water are mixed uniformly to obtain an environmentally friendly water-based paint.

[0078] The polyether polyol is a compound of polyether triol with 535 mg KOH / g of hydroxyl groups, polyether diol with 36-39 mg KOH / g of hydroxyl groups, and polyether diol with 153-188 mg KOH / g of hydroxyl groups in a mass ratio of 1:0.5:1.5.

[0079] Polyether triol with a hydroxyl number of 535 mgKOH / g, Arkema, France, model TO330. Polyether diol with a hydroxyl number of 36-39 mgKOH / g, Xuzhou Yihuiyang New Materials Co., Ltd., DL-3000D. Polyether diol with a hydroxyl number of 153-188 mgKOH / g, Jining Tangyi Chemical Co., Ltd., HSH-310.

[0080] The epoxy resins are epoxy resins with an epoxy equivalent of 210-230 g / mol, epoxy resins with an epoxy equivalent of 176-184 g / mol, and epoxy resins with an epoxy equivalent of 184-195 g / mol, with a mass ratio of 1:1.5:0.4.

[0081] Epoxy resin with an epoxy equivalent of 210-230 g / mol, Phoenix brand WSR 6101 epoxy resin.

[0082] Epoxy resin with an epoxy equivalent of 176-184 g / mol, Phoenix brand E54 epoxy resin.

[0083] Phoenix brand WSR 618 epoxy resin has an epoxy equivalent of 184-195 g / mol.

[0084] The preparation method of modified shell powder is as follows:

[0085] (1) 25 parts by mass of polyacrylate emulsion, 5 parts by mass of shell powder, and 100 parts by mass of water were mixed uniformly, and ultrasonically dispersed to obtain a mixture;

[0086] (2) stirring the mixture and heating it to 95°C for 3 h to obtain a reaction product;

[0087] (3) The reaction product was filtered, the filter cake was washed with deionized water, dried at 175°C for 60 minutes, and crushed to obtain modified shell powder.

[0088] The ultrasonic dispersion treatment conditions were as follows: ultrasonic dispersion at 40 kHz for 20 min.

[0089] The polyacrylate emulsion is model LA6588 from Shandong Li'ang New Material Technology Co., Ltd.

[0090] The shell powder is composed of shell powders with three different particle size ranges, specifically: the mass ratio of shell powders with particle size of 50-200 mesh, particle size of 400-600 mesh, and particle size of 1800-2000 mesh is 1.5:1:0.4.

[0091] The film-forming aid is dipropylene glycol methyl ether. CAS Registry Number 34590-94-8.

[0092] The leveling agent is a polyurethane rheology modifier. Beijing Dongfang Chennuo Chemical Technology Co., Ltd., model CN-2020.

[0093] The thickener is a solvent-free polyurethane thickener, Coatex polyurethane thickener from France, model CoapurXS83.

[0094] Comparative Example 1

[0095] The difference between this comparative example and Example 1 is that the polyurethane preparation method is different.

[0096] Weigh 3.5 parts by weight of hexamethylene diisocyanate, 1.4 parts by weight of polyethylene glycol 300, and 8 parts by weight of butanone, mix them evenly, heat to 63°C, and keep at that temperature for 2.5 hours. Then add 4.6 parts by weight of polyethylene glycol 300 and 0.5 parts by weight of stannous octoate, and react at 82°C for 3.5 hours. Cool down to 45°C, and then add 2.6 parts by weight of 1,4-butanediol and 1.2 parts by weight of triethylamine, mix evenly, heat to 72°C, and keep at that temperature for 4.5 hours. Cool to room temperature to obtain polyurethane resin.

[0097] Comparative Example 2

[0098] The difference between this comparative example and Example 1 is that the polyether polyol is a polyether triol with a hydroxyl number of 535 mgKOH / g, a polyether diol with a hydroxyl number of 36-39 mgKOH / g, and a polyether diol with a hydroxyl number of 153-188 mgKOH / g, which are compounded in a mass ratio of 1:1:1.

[0099] Comparative Example 3

[0100] The difference between this comparative example and Example 1 is that the polyether polyol is a polyether triol with a hydroxyl number of 350 mgKOH / g, a polyether diol with a hydroxyl number of 60-80 mgKOH / g, and a polyether diol with a hydroxyl number of 220 mgKOH / g, mixed in a mass ratio of 1:0.4:1.7. All are from Suzhou Senfida Chemical Co., Ltd.

[0101] Comparative Example 4

[0102] The difference between this comparative example and Example 1 is that the epoxy resin was replaced with acrylic resin, Guangdong Dongdun New Material Technology Co., Ltd., SEACRYL 11P28.

[0103] Comparative Example 5

[0104] The difference between this comparative example and Example 1 is that the epoxy resins are an epoxy resin with an epoxy equivalent weight of 210-230 g / mol, an epoxy resin with an epoxy equivalent weight of 176-184 g / mol, and an epoxy resin with an epoxy equivalent weight of 184-195 g / mol in a mass ratio of 1:1:1.

[0105] Comparative Example 6

[0106] The difference between this comparative example and Example 1 is that the epoxy resins used are epoxy resins with an epoxy equivalent of 252-273 g / mol, 121-143 g / mol, and 132-158 g / mol, respectively, in a mass ratio of 1:1.4:0.6. All of these were sourced from Langfang Xiangteng Chemical Co., Ltd.

[0107] Comparative Example 7

[0108] The difference between this comparative example and Example 1 is that the shell powder is composed of three different particle size ranges of shell powder, specifically: the mass ratio of shell powder with a particle size of 50-200 mesh, 400-600 mesh, and 1800-2000 mesh is 1:1:1.

[0109] Comparative Example 8

[0110] The difference between this comparative example and Example 1 is that the modification method of the shell powder is as follows: shell powder, silane coupling agent KH550, and 55wt% ethanol aqueous solution are mixed in a mass ratio of 1:0.03:7, reacted at 55°C for 2 hours, filtered, washed, and dried to obtain modified shell powder. The shell powder is composed of three different particle size ranges of shell powder, specifically: shell powder with a particle size of 50-200 mesh, 400-600 mesh, and 1800-2000 mesh in a mass ratio of 1.4:1:0.5.

[0111] Comparative Example 9

[0112] The difference between this comparative example and Example 1 is that the amount of polyacrylate emulsion is different.

[0113] The preparation method of modified shell powder is as follows:

[0114] (1) 15 parts by mass of polyacrylate emulsion, 8 parts by mass of shell powder, and 100 parts by mass of water were mixed uniformly, and ultrasonically dispersed to obtain a mixture;

[0115] (2) Stir the mixture and heat it to 94°C, keep it at that temperature for 3.5 h to obtain the reaction product;

[0116] (3) The reaction product was filtered, the filter cake was washed with deionized water, dried at 172℃ for 55 min, and then pulverized to obtain modified shell powder.

[0117] Performance Testing

[0118] Water-based coatings from Examples 1-3 and Comparative Examples 1-9 were applied to the surfaces of PVC boards with a diameter of 25 mm conforming to GB / T 9271-2008. After being placed in an environment of 25°C and 50% relative humidity for 48 hours, a paint film with a thickness of 250 μm was obtained and used as samples for performance testing. The PVC boards were ordinary transparent PVC, manufactured by Tashilon Cia (Shanghai) Trading Co., Ltd.

[0119] 1. Adhesion: Determined according to GB / T 9286-2021;

[0120] 2. Abrasion Resistance: Tests were conducted according to GB / T1768-2006 at a temperature of 25℃ and a relative humidity of 50%. The abrasion tester rotated at 60 r / min for 3 minutes. The abrasion resistance of the coating was expressed as wear mass loss (g), calculated using the following formula: Wear mass loss = Initial test panel mass - Test panel mass after test;

[0121] 3. Hardness: measured in accordance with GB / T 6739-2006;

[0122] 4. Anti-fouling: Use a marker to draw a 5 cm square on the paint surface and wipe it with a damp cloth to see if there is any ink residue.

[0123] 5. Anti-fungal property: After the sample is placed in an environment with a relative humidity of 70% for 3 months, the resistance to Aspergillus niger is tested in accordance with GB / T 1741-2020.

[0124] 6. Stability: Place the water-based paint in a constant temperature oven (temperature controlled at 50±5℃) for 30 days and observe whether there is floating color, precipitation or water separation. If there is no such phenomenon, it passes.

[0125] The results are shown in Table 1.

[0126] Table 1 Performance Test Results

[0127] Adhesion Wear resistance Antifouling hardness Antibacterial properties stability Example 1 Level 1 0.08 No residue HB Level 1 pass Example 2 Level 1 0.10 No residue HB Level 1 pass Example 3 Level 1 0.09 No residue HB Level 1 pass Comparative Example 1 Level 2 0.37 There are residues B Level 2 Failed Comparative Example 2 Level 1 0.25 No residue HB Level 1 pass Comparative Example 3 Level 1 0.27 No residue HB Level 1 pass Comparative Example 4 Level 2 0.28 No residue B Level 1 Failed Comparative Example 5 Level 1 0.14 No residue HB Level 1 pass Comparative Example 6 Level 1 0.17 No residue HB Level 1 pass Comparative Example 7 Level 2 0.22 There are residues B Level 2 Failed Comparative Example 8 Level 2 0.19 There are residues HB Level 2 Failed Comparative Example 9 Level 2 0.13 No residue HB Level 1 Failed

[0128] As shown in Table 1, compared with Comparative Examples 1-9, the environmentally friendly water-based coatings of Examples 1-3 have stronger adhesion to PVC boards, higher film hardness, better wear resistance, antibacterial and anti-fouling properties, and higher storage stability. Furthermore, the water-based coatings provided by this invention are more green and environmentally friendly.

[0129] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A preparation process of an antibacterial and antifouling environmentally friendly water-based coating, characterized in that: The following steps are involved: (1) Weigh 3-4 parts by weight of hexamethylene diisocyanate, 1-2 parts by weight of polyethylene glycol 300, and 6-9 parts by weight of butanone, mix them evenly, heat them to 60-65° C., keep them warm for 2-3 hours, continue to add 4-5 parts by weight of polyether polyol and 0.3-0.6 parts by weight of stannous octoate, react at 80-85° C. for 3-4 hours, cool them to 40-50° C., continue to add 2-3 parts by weight of 1,4-butanediol and 1-1.5 parts by weight of triethylamine, mix them evenly, heat them to 70-75° C., keep them warm for 4-5 hours, and cool them to room temperature to obtain a polyurethane resin; (2) 37-42 parts by weight of polyurethane resin, 14-19 parts by weight of epoxy resin, 5-8 parts by weight of modified shell powder, 1-2 parts by weight of thickener, 0.3-0.8 parts by weight of leveling agent, 1-2 parts by weight of film-forming aid and 20-25 parts by weight of deionized water are mixed uniformly to obtain an environmentally friendly water-based coating; The preparation method of modified shell powder is: (1) mixing 20-25 parts by weight of polyacrylate emulsion, 5-7 parts by weight of shell powder, and 100 parts by weight of water, and performing ultrasonic dispersion treatment to obtain a mixture; (2) stirring the mixture and heating it to 93° C.-95° C., and keeping the temperature for reaction for 3-4 hours to obtain a reaction product; (3) filtering the reaction product, washing the filter cake with deionized water, drying at 170° C.-175° C. for 50-60 min, and crushing to obtain modified shell powder; The polyether polyol is a mixture of a polyether triol with a hydroxyl number of 535 mgKOH / g, a polyether diol with a hydroxyl number of 36-39 mgKOH / g, and a polyether diol with a hydroxyl number of 153-188 mgKOH / g in a mass ratio of 1:0.2-0.5:1.5-1.8; The epoxy resin is a composite of an epoxy resin with an epoxy equivalent of 210-230 g / mol, an epoxy resin with an epoxy equivalent of 176-184 g / mol, and an epoxy resin with an epoxy equivalent of 184-195 g / mol in a mass ratio of 1:1.3-1.5:0.4-0.7; The shell powder is composed of shell powders of three different particle size ranges, specifically: the mass ratio of shell powders of particle size 50-200 mesh, particle size 400-600 mesh, and particle size 1800-2000 mesh is 1.3-1.5:1:0.4-0.

6.

2. The preparation process of the antibacterial and antifouling environmentally friendly water-based coating according to claim 1, characterized in that: The conditions of the ultrasonic dispersion treatment are: ultrasonic dispersion at 35-40 kHz for 15-20 min.

3. The preparation process of the antibacterial and antifouling environmentally friendly water-based coating according to claim 1, characterized in that: The film-forming aid is dipropylene glycol methyl ether.

4. The preparation process of the antibacterial and antifouling environmentally friendly water-based coating according to claim 1, characterized in that: The leveling agent is a polyurethane rheology modifier.

5. The preparation process of the antibacterial and antifouling environmentally friendly water-based coating according to claim 1, characterized in that: The thickener is a solvent-free polyurethane thickener.

6. An application of an antibacterial and antifouling environmentally friendly water-based coating prepared by the preparation process according to any one of claims 1 to 5, characterized in that: The water-based paint is used for spraying on the surface of furniture to decorate the surface of the PVC coating.