Antibacterial waterproof coating and preparation method thereof

Abstract

The invention provides application to the field of waterproof coatings, and particularly discloses an antibacterial waterproof coating and a preparation method thereof.The antibacterial waterproof coating is prepared from a mixed matrix, an antibacterial agent, functional filler and auxiliaries; the preparation method comprises the following steps: weighing the mixed matrix, the antibacterial agent, the functional filler and the assistant in parts by weight for later use; the mixed matrix and the functional filler are mixed, a grinding machine is used for pre-dispersion, the functional filler is evenly dispersed in the mixed matrix, and a mixed solution A is obtained; sequentially adding an antibacterial agent and an auxiliary agent into the mixed solution A, uniformly stirring to ensure full and uniform mixing, and filtering through a filter to obtain a mixed solution B; mixing the mixed solution B, standing, and removing bubbles to obtain the required antibacterial waterproof coating which has excellent waterproof performance and antibacterial performance.

Description

Technical Field

[0001] The present application relates to the field of waterproof coatings, and in particular to an antibacterial waterproof coating and a preparation method thereof. Background Art

[0002] Antibacterial and waterproof coating is a coating with special functions, which combines the two properties of antibacterial and waterproof to provide protection and hygiene guarantee for various surfaces.

[0003] As people pay more and more attention to environmental hygiene and health, the market demand for antibacterial waterproof coatings is also growing. This kind of coating not only has the functions of traditional waterproof coatings, but also can effectively inhibit the growth of microorganisms, providing people with a safer and more hygienic living and working environment.

[0004] The above-mentioned antibacterial and waterproof coating will age after long-term use, resulting in reduced antibacterial and waterproof properties. Based on the above statement, the present application provides an antibacterial and waterproof coating and a preparation method thereof. Summary of the invention

[0005] The purpose of the present application is to increase the service life of the antibacterial and waterproof coating, increase the antibacterial and waterproof properties, and provide an antibacterial and waterproof coating and a preparation method thereof compared to the prior art.

[0006] In a first aspect, the present application provides an antibacterial waterproof coating, comprising the following raw materials in parts by weight: 60-95 parts of a mixed matrix, 5-8 parts of an antibacterial agent, 1-5 parts of a functional filler, and 1-5 parts of an auxiliary agent;

[0007] The mixed matrix is ​​prepared by the following method:

[0008] The core-shell waterborne polyurethane-acrylate copolymer, polyhydroxyalkanoate and L-polylactic acid are weighed in a mass ratio of 30-60:15-30:10-15 for later use; the weighed polyhydroxyalkanoate and L-polylactic acid are added into an appropriate amount of water, stirred with a high-speed stirrer at a stirring speed of 200-300 r / min, and then dispersed with an ultrasonic dispersing device to form a uniform suspension A; the suspension A is slowly added into the emulsion of the core-shell waterborne polyurethane-acrylate copolymer and stirred with a magnetic stirring method; the pH value is adjusted to 8-9 during the stirring process, and the stirring time is 0.5-1h to obtain a mixed solution; the mixed solution is matured at a temperature of 30°C-40°C for 12-15h to obtain a mixed matrix.

[0009] Preferably, the antibacterial agent comprises lactoferrin peptide, plant-derived antibacterial agent and nano silver ions in a mass ratio of 7-10:4-6:2.

[0010] Preferably, the plant-derived antibacterial agent is prepared by the following method:

[0011] a. Wash the collected tea tree, garlic and rosemary, dry them at low temperature and crush them, pass them through a 30-40 mesh sieve to obtain plant fine powder;

[0012] b. Put the dried plant powder into the reaction vessel, add the enzyme solution in proportion, control the temperature of the reaction vessel to 40-65°C using a constant temperature water bath, adjust the pH value in the reaction vessel to 3-7, and stir at a speed of 100-200 rpm for 10-24 hours, then raise the temperature to 90-100°C to terminate the reaction and obtain an enzymatic hydrolysis product;

[0013] c. After filtering the enzymatic hydrolysis product, ethyl acetate is added to the filtrate for extraction, and the plant-derived antibacterial agent is prepared after purification.

[0014] By adopting the above technical scheme, the present application selects core-shell waterborne polyurethane-acrylate copolymer, polyhydroxyalkanoate and L-polylactic acid as the mixed matrix of the coating. By selecting the core-shell waterborne polyurethane-acrylate copolymer, it is possible to ensure the flexibility, wear resistance and waterproofness of the coating while using water as the dispersion medium, greatly reducing the emission of volatile organic compounds (VOC), which is more environmentally friendly; lactoferrin peptide, plant-derived antibacterial agent and nano silver ion are used as antibacterial agents, which have the advantages of high efficiency, low toxicity and low resistance to drug resistance. The three antibacterial agents act synergistically to enhance the antibacterial effect, which can improve the broad spectrum and durability of the antibacterial effect, and effectively increase the antibacterial and waterproof performance of the coating.

[0015] Preferably, the mass ratio of the tea tree, garlic and rosemary is 4-5:3-7:2, the mass ratio of the plant fine powder to the enzyme solution is 1:10, and the enzyme solution is a mixed solution of cellulase and protease at a ratio of 4:5.

[0016] Preferably, the functional filler is a mixture of nano-titanium dioxide, silicon micropowder and graphene, and the mass ratio of the nano-titanium dioxide, silicon micropowder and graphene is 5-8:12-17:4.

[0017] Preferably, the auxiliary agent includes 10-15 parts of dispersant, 5-8 parts of defoamer, 4-5 parts of leveling agent and 1-3 parts of thickener in terms of mass ratio.

[0018] In a second aspect, the present application provides a method for preparing an antibacterial waterproof coating, comprising the following preparation steps:

[0019] S1. Weigh the mixed matrix, antimicrobial agent, functional filler and auxiliary agent by weight for later use;

[0020] S2, mixing the mixed matrix and the functional filler, and pre-dispersing them using a grinder to uniformly disperse the functional filler in the mixed matrix to obtain a mixed solution A;

[0021] S3, add antimicrobial agent and auxiliary agent to mixed solution A in sequence, stir evenly to ensure full mixing, and filter through a filter to obtain mixed solution B;

[0022] S4, mixing the mixed solution B, letting it stand and removing bubbles to obtain the desired antibacterial and waterproof coating.

[0023] Compared with the prior art, the advantages of the present application are as follows: the present application selects core-shell waterborne polyurethane-acrylate copolymer, polyhydroxyalkanoate and L-polylactic acid as the mixed matrix of the coating. By selecting the core-shell waterborne polyurethane-acrylate copolymer, the coating can be ensured to have flexibility, wear resistance and waterproofness while using water as the dispersion medium, thereby greatly reducing the emission of volatile organic compounds (VOCs) and being more environmentally friendly; lactoferrin peptide, plant-derived antibacterial agent and nano silver ion are used as antibacterial agents, which have the advantages of high efficiency, low toxicity and low resistance to drug resistance. The three antibacterial agents act synergistically to enhance the antibacterial effect, improve the broad-spectrum and durability of the antibacterial effect, and effectively increase the antibacterial and waterproof performance of the coating. DETAILED DESCRIPTION

[0024] The present application is further described in detail below with reference to the embodiments.

[0025] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making any creative work shall fall within the scope of protection of this application.

[0026] Embodiment 1:

[0027] The present invention provides an antibacterial waterproof coating, comprising the following raw materials in parts by weight: 60 parts of a mixed matrix, 5 parts of an antibacterial agent, 1 part of a functional filler, and 1 part of an auxiliary agent;

[0028] The functional filler is a mixture of nano-titanium dioxide, silicon micropowder and graphene, and the mass ratio of nano-titanium dioxide, silicon micropowder and graphene is 5:12:4;

[0029] The additives include 10 parts of dispersant, 5 parts of defoamer, 4 parts of leveling agent and 1 part of thickener by mass ratio.

[0030] More specifically, the dispersant is a polyacrylate dispersant, the defoamer is a polyether-modified silicon defoamer, the leveling agent is a BYK-333 leveling agent, and the thickener is a hydroxyethyl cellulose thickener.

[0031] The mixed matrix is ​​prepared by the following method:

[0032] The core-shell waterborne polyurethane-acrylate copolymer, polyhydroxyalkanoate and L-polylactic acid are weighed in a mass ratio of 30:15:10 for later use; the weighed polyhydroxyalkanoate and L-polylactic acid are added into an appropriate amount of water, stirred with a high-speed stirrer at a stirring speed of 200 r / min, and then dispersed with an ultrasonic dispersing device to form a uniform suspension A; the suspension A is slowly added into the emulsion of the core-shell waterborne polyurethane-acrylate copolymer and stirred with a magnetic stirring method; the pH value is adjusted to 8 during the stirring process; the stirring time is 0.5 h to obtain a mixed solution; the mixed solution is aged at a temperature of 30° C. for 12 h to obtain a mixed matrix.

[0033] The antimicrobial agent includes lactoferrin peptide, plant-derived antimicrobial agent and nano silver ion in a mass ratio of 7:4:2.

[0034] Furthermore, the plant-derived antibacterial agent is prepared by the following method:

[0035] a. Wash the collected tea tree, garlic and rosemary, dry them at low temperature and crush them, pass them through a 30-mesh sieve to obtain plant fine powder;

[0036] b. Put the dried plant powder into the reaction vessel, add the enzyme solution in proportion, control the temperature of the reaction vessel to 40°C using a constant temperature water bath, adjust the pH value in the reaction vessel to 3, and stir at a speed of 100 rpm. After stirring for 10 hours, raise the temperature to 90°C to terminate the reaction and obtain the enzymatic hydrolysis product;

[0037] c. After filtering the enzymatic hydrolysis product, ethyl acetate is added to the filtrate for extraction, and the plant-derived antibacterial agent is prepared after purification.

[0038] It should be noted that, in this embodiment, the mass ratio of tea tree, garlic and rosemary is 4:3:2, the mass ratio of plant powder to enzyme solution is 1:10, and the enzyme solution is a mixed solution of cellulase and protease at a ratio of 4:5.

[0039] A method for preparing an antibacterial waterproof coating comprises the following preparation steps:

[0040] S1. Weigh the mixed matrix, antimicrobial agent, functional filler and auxiliary agent by weight for later use;

[0041] S2, mixing the mixed matrix and the functional filler, and pre-dispersing them using a grinder to uniformly disperse the functional filler in the mixed matrix to obtain a mixed solution A;

[0042] S3, add antimicrobial agent and auxiliary agent to mixed solution A in sequence, stir evenly to ensure full mixing, and filter through a filter to obtain mixed solution B;

[0043] S4, mixing the mixed solution B, letting it stand and removing bubbles to obtain the desired antibacterial and waterproof coating.

[0044] Embodiment 2:

[0045] The present invention provides an antibacterial waterproof coating, comprising the following raw materials in parts by weight: 95 parts of a mixed matrix, 8 parts of an antibacterial agent, 5 parts of a functional filler, and 5 parts of an auxiliary agent;

[0046] The functional filler is a mixture of nano-titanium dioxide, silicon micropowder and graphene, and the mass ratio of nano-titanium dioxide, silicon micropowder and graphene is 8:17:4;

[0047] The additives include 15 parts of dispersant, 8 parts of defoamer, 5 parts of leveling agent, and 3 parts of thickener in terms of mass ratio. More specifically, the dispersant is a polyacrylate dispersant, the defoamer is a polyether modified silicone defoamer, the leveling agent is BYK-333 leveling agent, and the thickener is a hydroxyethyl cellulose thickener.

[0048] The mixed matrix is ​​prepared by the following method:

[0049] The core-shell waterborne polyurethane-acrylate copolymer, polyhydroxyalkanoate and L-polylactic acid are weighed in a mass ratio of 60:30:15 for later use; the weighed polyhydroxyalkanoate and L-polylactic acid are added into an appropriate amount of water, stirred with a high-speed stirrer at a stirring speed of 300 r / min, and then dispersed with an ultrasonic dispersing device to form a uniform suspension A; the suspension A is slowly added into the emulsion of the core-shell waterborne polyurethane-acrylate copolymer and stirred with a magnetic stirring method; the pH value is adjusted to 9 during the stirring process; the stirring time is 1 hour to obtain a mixed solution; the mixed solution is aged at a temperature of 40° C. for 15 hours to obtain a mixed matrix.

[0050] The antibacterial agent includes lactoferrin peptide, plant-derived antibacterial agent and nano silver ion in a mass ratio of 10:6:2.

[0051] Furthermore, the plant-derived antibacterial agent is prepared by the following method:

[0052] a. Wash the collected tea tree, garlic and rosemary, dry them at low temperature and crush them, pass them through a 40-mesh sieve to obtain plant fine powder;

[0053] b. Put the dried plant powder into a reaction vessel, add the enzyme solution in proportion, control the temperature of the reaction vessel to 65°C using a constant temperature water bath, adjust the pH value in the reaction vessel to 7, and stir at a speed of 200 rpm. After stirring for 24 hours, raise the temperature to 100°C to terminate the reaction and obtain an enzymatic hydrolysis product;

[0054] c. After filtering the enzymatic hydrolysis product, ethyl acetate is added to the filtrate for extraction, and the plant-derived antibacterial agent is prepared after purification.

[0055] It should be noted that, in this embodiment, the mass ratio of tea tree, garlic and rosemary is 5:7:2, the mass ratio of plant fine powder to enzyme solution is 1:10, and the enzyme solution is a mixed solution of cellulase and protease at a ratio of 4:5.

[0056] A method for preparing an antibacterial waterproof coating comprises the following preparation steps:

[0057] S1. Weigh the mixed matrix, antimicrobial agent, functional filler and auxiliary agent by weight for later use;

[0058] S2, mixing the mixed matrix and the functional filler, and pre-dispersing them using a grinder to uniformly disperse the functional filler in the mixed matrix to obtain a mixed solution A;

[0059] S3, add antimicrobial agent and auxiliary agent to mixed solution A in sequence, stir evenly to ensure full mixing, and filter through a filter to obtain mixed solution B;

[0060] S4, mixing the mixed solution B, letting it stand and removing bubbles to obtain the desired antibacterial and waterproof coating.

[0061] Embodiment 3:

[0062] The present invention provides an antibacterial waterproof coating, comprising the following raw materials in parts by weight: 80 parts of a mixed matrix, 7 parts of an antibacterial agent, 3 parts of a functional filler, and 3 parts of an auxiliary agent;

[0063] The functional filler is a mixture of nano-titanium dioxide, silicon micropowder and graphene, and the mass ratio of nano-titanium dioxide, silicon micropowder and graphene is 6:15:4;

[0064] The additives include 12 parts of dispersant, 7 parts of defoamer, 4 parts of leveling agent, and 2 parts of thickener in terms of mass ratio. More specifically, the dispersant is a polyacrylate dispersant, the defoamer is a polyether modified silicone defoamer, the leveling agent is BYK-333 leveling agent, and the thickener is a hydroxyethyl cellulose thickener.

[0065] The mixed matrix is ​​prepared by the following method:

[0066] The core-shell waterborne polyurethane-acrylate copolymer, polyhydroxyalkanoate and L-polylactic acid are weighed in a mass ratio of 50:25:12 for later use; the weighed polyhydroxyalkanoate and L-polylactic acid are added into an appropriate amount of water, stirred with a high-speed stirrer at a stirring speed of 250 r / min, and then dispersed with an ultrasonic dispersing device to form a uniform suspension A; the suspension A is slowly added into the emulsion of the core-shell waterborne polyurethane-acrylate copolymer and stirred with a magnetic stirring method; the pH value is adjusted to 8 during the stirring process; the stirring time is 0.6 h to obtain a mixed solution; the mixed solution is matured at a temperature of 35° C. for 14 h to obtain a mixed matrix.

[0067] The antibacterial agent includes lactoferrin peptide, plant-derived antibacterial agent and nano silver ion in a mass ratio of 8:5:2.

[0068] Furthermore, the plant-derived antibacterial agent is prepared by the following method:

[0069] a. Wash the collected tea tree, garlic and rosemary, dry them at low temperature and crush them, pass them through a 30-mesh sieve to obtain plant fine powder;

[0070] b. Put the dried plant powder into the reaction vessel, add the enzyme solution in proportion, control the temperature of the reaction vessel to 60°C using a constant temperature water bath, adjust the pH value in the reaction vessel to 5, and stir at a stirring speed of 150 rpm. After stirring for 20 hours, raise the temperature to 95°C to terminate the reaction and obtain the enzymatic hydrolysis product;

[0071] c. After filtering the enzymatic hydrolysis product, ethyl acetate is added to the filtrate for extraction, and the plant-derived antibacterial agent is prepared after purification.

[0072] It should be noted that, in this embodiment, the mass ratio of tea tree, garlic and rosemary is 4:5:2, the mass ratio of plant powder to enzyme solution is 1:10, and the enzyme solution is a mixed solution of cellulase and protease at a ratio of 4:5.

[0073] A method for preparing an antibacterial waterproof coating comprises the following preparation steps:

[0074] S1. Weigh the mixed matrix, antimicrobial agent, functional filler and auxiliary agent by weight for later use;

[0075] S2, mixing the mixed matrix and the functional filler, and pre-dispersing them using a grinder to uniformly disperse the functional filler in the mixed matrix to obtain a mixed solution A;

[0076] S3, add antimicrobial agent and auxiliary agent to mixed solution A in sequence, stir evenly to ensure full mixing, and filter through a filter to obtain mixed solution B;

[0077] S4, mixing the mixed solution B, letting it stand and removing bubbles to obtain the desired antibacterial and waterproof coating.

[0078] In order to verify the comprehensive performance of the antibacterial and waterproof coatings prepared in Examples 1-3 of the present application, the applicant set up Comparative Examples 1-2, which are as follows:

[0079] Comparative Example 1:

[0080] An antibacterial waterproof coating comprises the following raw materials in parts by weight: 60 parts of a mixed matrix, 5 parts of an antibacterial agent, 1 part of a functional filler, and 1 part of an auxiliary agent;

[0081] The functional filler is a mixture of nano-titanium dioxide, silicon micropowder and graphene, and the mass ratio of nano-titanium dioxide, silicon micropowder and graphene is 5:12:4;

[0082] The additives include 10 parts of dispersant, 5 parts of defoamer, 4 parts of leveling agent and 1 part of thickener by mass ratio. More specifically, the dispersant is a polyacrylate dispersant, the defoamer is a polyether modified silicone defoamer, the leveling agent is BYK-333 leveling agent, and the thickener is a hydroxyethyl cellulose thickener.

[0083] The mixed matrix is ​​a core-shell type waterborne polyurethane-acrylate copolymer.

[0084] The antimicrobial agent includes lactoferrin peptide, plant-derived antimicrobial agent and nano silver ion in a mass ratio of 7:4:2.

[0085] Furthermore, the plant-derived antibacterial agent is prepared by the following method:

[0086] a. Wash the collected tea tree, garlic and rosemary, dry them at low temperature and crush them, pass them through a 30-mesh sieve to obtain plant fine powder;

[0087] b. Put the dried plant powder into the reaction vessel, add the enzyme solution in proportion, control the temperature of the reaction vessel to 40°C using a constant temperature water bath, adjust the pH value in the reaction vessel to 3, and stir at a speed of 100 rpm. After stirring for 10 hours, raise the temperature to 90°C to terminate the reaction and obtain the enzymatic hydrolysis product;

[0088] c. After filtering the enzymatic hydrolysis product, ethyl acetate is added to the filtrate for extraction, and the plant-derived antibacterial agent is prepared after purification.

[0089] It should be noted that, in this embodiment, the mass ratio of tea tree, garlic and rosemary is 4:3:2, the mass ratio of plant powder to enzyme solution is 1:10, and the enzyme solution is a mixed solution of cellulase and protease at a ratio of 4:5.

[0090] A method for preparing an antibacterial waterproof coating comprises the following preparation steps:

[0091] S1. Weigh the mixed matrix, antimicrobial agent, functional filler and auxiliary agent by weight for later use;

[0092] S2, mixing the mixed matrix and the functional filler, and pre-dispersing them using a grinder to uniformly disperse the functional filler in the mixed matrix to obtain a mixed solution A;

[0093] S3, add antimicrobial agent and auxiliary agent to mixed solution A in sequence, stir evenly to ensure full mixing, and filter through a filter to obtain mixed solution B;

[0094] S4, mixing the mixed solution B, letting it stand and removing bubbles to obtain the desired antibacterial and waterproof coating.

[0095] Comparative Example 2:

[0096] An antibacterial waterproof coating comprises the following raw materials in parts by weight: 60 parts of a mixed matrix, 5 parts of an antibacterial agent, 1 part of a functional filler, and 1 part of an auxiliary agent;

[0097] The functional filler is a mixture of nano-titanium dioxide, silicon micropowder and graphene, and the mass ratio of nano-titanium dioxide, silicon micropowder and graphene is 5:12:4;

[0098] The additives include 10 parts of dispersant, 5 parts of defoamer, 4 parts of leveling agent and 1 part of thickener by mass ratio. More specifically, the dispersant is a polyacrylate dispersant, the defoamer is a polyether modified silicone defoamer, the leveling agent is BYK-333 leveling agent, and the thickener is a hydroxyethyl cellulose thickener.

[0099] The mixed matrix is ​​prepared by the following method:

[0100] The core-shell waterborne polyurethane-acrylate copolymer, polyhydroxyalkanoate and L-polylactic acid are weighed in a mass ratio of 30:15:10 for later use; the weighed polyhydroxyalkanoate and L-polylactic acid are added into an appropriate amount of water, stirred with a high-speed stirrer at a stirring speed of 200 r / min, and then dispersed with an ultrasonic dispersing device to form a uniform suspension A; the suspension A is slowly added into the emulsion of the core-shell waterborne polyurethane-acrylate copolymer and stirred with a magnetic stirring method; the pH value is adjusted to 8 during the stirring process; the stirring time is 0.5 h to obtain a mixed solution; the mixed solution is aged at a temperature of 30° C. for 12 h to obtain a mixed matrix.

[0101] Among them, the antibacterial agent is nano silver ion.

[0102] A method for preparing an antibacterial waterproof coating comprises the following preparation steps:

[0103] S1. Weigh the mixed matrix, antimicrobial agent, functional filler and auxiliary agent by weight for later use;

[0104] S2, mixing the mixed matrix and the functional filler, and pre-dispersing them using a grinder to uniformly disperse the functional filler in the mixed matrix to obtain a mixed solution A;

[0105] S3, add antimicrobial agent and auxiliary agent to mixed solution A in sequence, stir evenly to ensure full mixing, and filter through a filter to obtain mixed solution B;

[0106] S4, mixing the mixed solution B, letting it stand and removing bubbles to obtain the desired antibacterial and waterproof coating.

[0107] Performance testing:

[0108] According to the test standards, the antibacterial and waterproof coatings prepared in Examples 1-3 of the present application and Comparative Examples 1-2 were coated on glass surfaces to prepare test specimens, and the specimens were placed in a test room at a temperature of 25°C and a relative humidity of 55% for 2 hours, and then their performance was tested.

[0109] According to the HG / T 3950-2007 Antibacterial Coatings standard, the samples were irradiated with a 30W ultraviolet lamp with a wavelength of 253.7nm at a distance of 0.8-1.0 meters for 100 hours, and then the antibacterial performance test was carried out to detect the killing rate of Staphylococcus aureus and Escherichia coli.

[0110] According to GB / T 16777-2008 “Test methods for building waterproof coatings”, maintain a pressure of 0.3MPa for 30 minutes and test the water permeability of the sample.

[0111] The test results are shown in Table 1 below:

[0112]

[0113] It can be seen from the data shown in Table 1 above that the antibacterial and waterproof coatings prepared in Examples 1-3 of the present application have strong waterproofness, high antibacterial properties and excellent comprehensive performance.

[0114] It can be seen from the data shown in Example 1 and Comparative Example 1 that Example 1 of the present application can significantly improve the waterproof performance of the coating by pre-preparing a core-shell type waterborne polyurethane-acrylate copolymer, polyhydroxyalkanoate and L-polylactic acid as a mixed matrix, compared with a direct core-shell type waterborne polyurethane-acrylate copolymer as a matrix.

[0115] It can be seen from the data shown in Example 1 and Comparative Example 2 that Example 1 of the present application can further enhance the antibacterial properties of the coating by using lactoferrin peptide, plant-derived antibacterial agent and nano silver ion as antibacterial agent.

[0116] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. An antibacterial waterproof coating, characterized in that: The raw materials include the following parts by weight: 60-95 parts of mixed matrix, 5-8 parts of antibacterial agent, 1-5 parts of functional filler, and 1-5 parts of auxiliary agent; The mixed matrix is ​​prepared by the following method: The core-shell waterborne polyurethane-acrylate copolymer, polyhydroxyalkanoate and L-polylactic acid are weighed in a mass ratio of 30-60:15-30:10-15 for later use; the weighed polyhydroxyalkanoate and L-polylactic acid are added into an appropriate amount of water, stirred with a high-speed stirrer at a stirring speed of 200-300 r / min, and then dispersed with an ultrasonic dispersing device to form a uniform suspension A; the suspension A is slowly added into the emulsion of the core-shell waterborne polyurethane-acrylate copolymer and stirred with a magnetic stirring method; the pH value is adjusted to 8-9 during the stirring process, and the stirring time is 0.5-1h to obtain a mixed solution; the mixed solution is matured at a temperature of 30°C-40°C for 12-15h to obtain a mixed matrix.

2. The antibacterial waterproof coating according to claim 1, characterized in that: The antibacterial agent comprises lactoferrin peptide, plant-derived antibacterial agent and nano silver ion in a ratio of 7-10:4-6:

2.

3. The antibacterial waterproof coating according to claim 2, characterized in that: The plant-derived antibacterial agent is prepared by the following method: a. Wash the collected tea tree, garlic and rosemary, dry them at low temperature and crush them, pass them through a 30-40 mesh sieve to obtain plant fine powder; b. Put the dried plant powder into the reaction vessel, add the enzyme solution in proportion, control the temperature of the reaction vessel to 40-65°C using a constant temperature water bath, adjust the pH value in the reaction vessel to 3-7, and stir at a speed of 100-200 rpm for 10-24 hours, then raise the temperature to 90-100°C to terminate the reaction and obtain an enzymatic hydrolysis product; c. After filtering the enzymatic hydrolysis product, ethyl acetate is added to the filtrate for extraction, and the plant-derived antibacterial agent is prepared after purification.

4. The antibacterial waterproof coating according to claim 3, characterized in that: The mass ratio of the tea tree, garlic and rosemary is 4-5:3-7:2, the mass ratio of the plant fine powder to the enzyme solution is 1:10, and the enzyme solution is a mixed solution of cellulase and protease at a ratio of 4:

5.

5. The antibacterial waterproof coating and preparation method thereof according to claim 3, characterized in that: The functional filler is a mixture of nano titanium dioxide, silicon micropowder and graphene, and the mass ratio of the nano titanium dioxide, silicon micropowder and graphene is 5-8:12-17:

4.

6. The antibacterial waterproof coating according to claim 3, characterized in that: The auxiliary agent comprises 10-15 parts of dispersant, 5-8 parts of defoamer, 4-5 parts of leveling agent and 1-3 parts of thickener in terms of mass ratio.

7. A method for preparing an antibacterial waterproof coating according to any one of claims 1 to 6, characterized in that: The method comprises the following preparation steps: S1. Weigh the mixed matrix, antimicrobial agent, functional filler and auxiliary agent by weight for later use; S2, mixing the mixed matrix and the functional filler, and pre-dispersing them using a grinder to uniformly disperse the functional filler in the mixed matrix to obtain a mixed solution A; S3, add antimicrobial agent and auxiliary agent to mixed solution A in sequence, stir evenly to ensure full mixing, and filter through a filter to obtain mixed solution B; S4, mixing the mixed solution B, letting it stand and removing bubbles to obtain the desired antibacterial and waterproof coating.

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