Antibacterial and bacteriostatic environment-friendly coating and preparation method thereof

Abstract

The invention relates to an antibacterial and bacteriostatic environment-friendly coating and a preparation method thereof, and belongs to the technical field of environment-friendly coatings. The antibacterial and bacteriostatic environment-friendly coating comprises the following components in parts by weight: 40-60 parts of water-based acrylic resin, 1-5 parts of a defoaming agent, 1-5 parts of a defoaming agent and 1-5 parts of a dispersing agent. The coating is prepared from the following components in parts by weight: 5 to 10 parts of modified chitosan derivative, 3 to 8 parts of nano zinc oxide / cerium dioxide complex, 2 to 5 parts of diatomite loaded plant essential oil, 1 to 3 parts of plant source mildew preventive, 2 to 4 parts of dispersing agent, 10 to 25 parts of deionized water and 0.5 to 2 parts of photocatalyst. Through physical adsorption of the modified chitosan derivative, chemical oxidation of the nano-zinc oxide / cerium dioxide complex and biological inhibition of the diatomite-loaded plant essential oil, bacteria resistance and bacteriostasis can be carried out in multiple modes, the risk of drug resistance is reduced, volatile organic compounds cannot be released, and the environment cannot be polluted; and the nano zinc oxide / cerium dioxide complex is matched with the photocatalyst, so that organic pollutants can be decomposed under natural light, and the method is more environment-friendly.

Description

Technical Field

[0001] The present invention belongs to the technical field of environmentally friendly coatings, and in particular relates to an antibacterial and antimicrobial environmentally friendly coating and a preparation method thereof. Background Art

[0002] Paint is a material applied to surfaces to form a firmly adherent, continuous film. It typically consists of primary ingredients such as resins, oils, and emulsions, along with pigments, fillers, and additives. It can be formulated with either organic solvents or water. Paint plays a vital role in the national economy and daily life, with widespread applications in fields such as construction and automotive manufacturing. It primarily protects, decorates, and improves the surface properties of objects. Common examples include floor paints and decorative paints.

[0003] Antimicrobial coatings are specialized coatings with antimicrobial properties. They form an antimicrobial layer on the surface, effectively inhibiting and killing microorganisms such as bacteria, viruses, fungi, and mold, thereby preventing their growth and reproduction. Antimicrobial coatings are widely used in medical facilities, food processing, public spaces, household appliances, and personal electronics. In these environments, antimicrobial coatings effectively reduce microbial contamination and protect public health and safety.

[0004] However, traditional antibacterial coatings mostly rely on chemical fungicides such as silver ions and quaternary ammonium salts, which pose the risk of heavy metal pollution (such as nanosilver migration) and bacterial resistance. Organic antibacterial agents such as triclosan are easily decomposed and become ineffective, and may release volatile organic compounds, polluting the environment. In response to this, the present application proposes an antibacterial and antimicrobial environmentally friendly coating and its preparation method. Summary of the Invention

[0005] The purpose of the present invention is to provide a composite antibacterial and antibacterial environmentally friendly coating and its preparation method in order to solve the above problems.

[0006] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0007] The first aspect of the present invention provides an antibacterial and antifungal environmentally friendly coating, comprising the following components in parts by weight: 40-60 parts of a water-based acrylic resin, 5-10 parts of a modified chitosan derivative, 3-8 parts of a nano-zinc oxide / cerium dioxide complex, 2-5 parts of diatomaceous earth-loaded plant essential oil, 1-3 parts of a plant-derived mildewcide, 2-4 parts of a dispersant, 10-25 parts of deionized water, and 0.5-2 parts of a photocatalyst.

[0008] As a further optimized solution of the present invention, the modified chitosan derivative is carboxymethyl chitosan or quaternized chitosan.

[0009] As a further optimized solution of the present invention, the mass ratio of the nano-zinc oxide to cerium dioxide complex is 1 to 3:1, and the average particle size is 20 to 50 nm.

[0010] As a further optimized solution of the present invention, the surface of the nano-zinc oxide and cerium dioxide composite is coated with a polydopamine layer, and the composite is doped with 1-3 wt% of nitrogen.

[0011] As a further optimized solution of the present invention, the diatomaceous earth-loaded plant essential oils 2-5 are at least one of tea tree essential oil, eucalyptus essential oil or peppermint essential oil.

[0012] As a further optimization solution of the present invention, the photocatalyst is at least one of g-C3N4 or black phosphorus quantum dots.

[0013] As a further optimized solution of the present invention, the plant-derived mildew inhibitor is one of matrine, osthole or baicalein.

[0014] A second aspect of the present invention provides a method for preparing an antibacterial and antimicrobial environmentally friendly coating, comprising the following steps:

[0015] Step 1: mixing nano zinc oxide and cerium dioxide by ball milling, modifying with a silane coupling agent, and then dispersing in ethanol to obtain a nano zinc oxide / cerium dioxide composite;

[0016] Step 2: reacting chitosan with an organic acid to prepare a water-soluble modified chitosan derivative;

[0017] Step 3: Mix the nano zinc oxide / cerium dioxide complex and the modified chitosan derivative, then stir and emulsify the aqueous acrylic resin, deionized water and dispersant, and add the mixture into the nano zinc oxide / cerium dioxide complex and the modified chitosan derivative;

[0018] Step 4: Add the diatomaceous earth-loaded plant essential oil, the plant-derived mildew inhibitor and the photocatalyst into the mixed solution of step 3 and stir to mix, adjust the pH of the mixed solution to 8-9, and filter to obtain the finished product.

[0019] The beneficial effects of the present invention are:

[0020] 1. Through the physical adsorption of modified chitosan derivatives, the chemical oxidation of nano-zinc oxide / cerium dioxide complexes, and the bioinhibition of diatomaceous earth-loaded plant essential oils, antibacterial and antimicrobial effects can be achieved in multiple ways. This will not produce heavy metal pollution and reduce the risk of drug resistance in pathogens. It will not release volatile organic compounds and pollute the environment. In addition, the nano-zinc oxide / cerium dioxide complexes combined with photocatalysts can decompose organic pollutants under natural light, making it more environmentally friendly.

[0021] 2. By coating the surface of the nano-zinc oxide / cerium dioxide complex with a polydopamine layer, the agglomeration problem of nanoparticles in the nano-zinc oxide / cerium dioxide complex can be solved, and the dispersibility can be improved. In addition, the plant-based mildew inhibitor can inhibit mold and further improve the antibacterial and antifungal effect of the coating. DETAILED DESCRIPTION

[0022] The present application is further described in detail below in conjunction with specific implementation methods. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0023] Example 1

[0024] The composition of raw materials is shown in Table 1;

[0025] Table 1

[0026]

[0027] The preparation process is as follows:

[0028] Step 1: mixing nano zinc oxide and cerium dioxide by ball milling, modifying with a silane coupling agent, and then dispersing in ethanol to obtain a nano zinc oxide / cerium dioxide composite;

[0029] Step 2: reacting carboxymethyl chitosan with an organic acid to prepare a water-soluble modified chitosan derivative;

[0030] Step 3: Mix the nano zinc oxide / cerium dioxide complex and the modified chitosan derivative, then stir and emulsify the aqueous acrylic resin, deionized water and dispersant, and add the mixture into the nano zinc oxide / cerium dioxide complex and the modified chitosan derivative;

[0031] Step 4: Add diatomaceous earth loaded with tea tree essential oil, matrine and g-C3N4 into the mixed solution of step 3 and stir to mix, adjust the pH of the mixed solution to 8-9, and filter to obtain the finished product.

[0032] Example 2

[0033] The composition of raw materials is shown in Table 2;

[0034] Table 2

[0035]

[0036] The preparation process is as follows:

[0037] Step 1: mixing nano zinc oxide and cerium dioxide by ball milling, modifying with a silane coupling agent, and then dispersing in ethanol to obtain a nano zinc oxide / cerium dioxide composite;

[0038] Step 2: reacting quaternized chitosan with an organic acid to prepare a water-soluble modified chitosan derivative;

[0039] Step 3: Mix the nano zinc oxide / cerium dioxide complex and the modified chitosan derivative, then stir and emulsify the aqueous acrylic resin, deionized water and dispersant, and add the mixture into the nano zinc oxide / cerium dioxide complex and the modified chitosan derivative;

[0040] Step 4: Add diatomaceous earth loaded with tea tree essential oil, matrine and g-C3N4 into the mixed solution of step 3 and stir to mix, adjust the pH of the mixed solution to 8-9, and filter to obtain the finished product.

[0041] Example 3

[0042] The composition of raw materials is shown in Table 3;

[0043] Table 3

[0044]

[0045] Step 1: mixing nano zinc oxide and cerium dioxide by ball milling, modifying with a silane coupling agent, and then dispersing in ethanol to obtain a nano zinc oxide / cerium dioxide composite;

[0046] Step 2: reacting carboxymethyl chitosan with an organic acid to prepare a water-soluble modified chitosan derivative;

[0047] Step 3: Mix the nano zinc oxide / cerium dioxide complex and the modified chitosan derivative, then stir and emulsify the aqueous acrylic resin, deionized water and dispersant, and add the mixture into the nano zinc oxide / cerium dioxide complex and the modified chitosan derivative;

[0048] Step 4: Add diatomaceous earth loaded with eucalyptus essential oil, baicalein and g-C3N4 to the mixed solution of step 3 and stir to mix, adjust the pH of the mixed solution to 8-9, and filter to obtain the finished product.

[0049] After testing, the technical performance indicators and experimental results of the present invention are as follows Table 4:

[0050] Table 4

[0051]

[0052]

[0053] Tests have shown that this antibacterial and antimicrobial environmentally friendly coating has a high antibacterial rate, low VOC content, low pollution emissions, is washable, and has a long service life. The modified chitosan derivative in the coating acts as a natural antibacterial agent, which can physically adsorb pathogens and destroy microbial cell membranes. The nano-zinc oxide / cerium dioxide complex can chemically oxidize pathogens and has a broad-spectrum antibacterial effect. It can be combined with a photocatalyst to decompose organic pollutants under natural light. Diatomaceous earth loaded with plant essential oils can biologically inhibit pathogens, thereby inhibiting mold. The aromatic insect repellent and plant-based mildew inhibitors can inhibit mold and have good biodegradability to reduce the risk of drug resistance of pathogens. It will not release volatile organic compounds and pollute the environment. It is suitable for medical, home and public facilities and other scenarios.

[0054] The above-described embodiments merely illustrate several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, and all such variations and improvements fall within the scope of protection of the present invention.

Claims

1. An antibacterial and antimicrobial environmentally friendly coating, characterized in that: The invention comprises the following components in parts by weight: 40-60 parts of water-based acrylic resin, 5-10 parts of modified chitosan derivative, 3-8 parts of nano zinc oxide / cerium dioxide complex, 2-5 parts of diatomaceous earth-loaded plant essential oil, 1-3 parts of plant-derived mildew inhibitor, 2-4 parts of dispersant, 10-25 parts of deionized water and 0.5-2 parts of photocatalyst.

2. The antibacterial and antimicrobial environmentally friendly coating according to claim 1, characterized in that: The modified chitosan derivative is carboxymethyl chitosan or quaternized chitosan.

3. The antibacterial and antimicrobial environmentally friendly coating according to claim 1, characterized in that: The mass ratio of the nano zinc oxide to cerium dioxide complex is 1 to 3:1, and the average particle size is 20 to 50 nm.

4. The antibacterial and antimicrobial environmentally friendly coating according to claim 3, characterized in that: The surface of the nano zinc oxide and cerium dioxide complex is coated with a polydopamine layer, and the complex is doped with 1-3 wt% of nitrogen.

5. The antibacterial and antimicrobial environmentally friendly coating according to claim 1, characterized in that: The diatomaceous earth-loaded plant essential oils 2-5 are at least one of tea tree essential oil, eucalyptus essential oil or peppermint essential oil.

6. The antibacterial and antimicrobial environmentally friendly coating according to claim 1, characterized in that: The photocatalyst is at least one of g-C3N4 or black phosphorus quantum dots.

7. The antibacterial and antimicrobial environmentally friendly coating according to claim 1, characterized in that: The plant-derived mildew inhibitor is one of matrine, osthole or baicalein.

8. A method for preparing an antibacterial and antimicrobial environmentally friendly coating, for preparing an antibacterial and antimicrobial environmentally friendly coating according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: mixing nano zinc oxide and cerium dioxide by ball milling, modifying with a silane coupling agent, and then dispersing in ethanol to obtain a nano zinc oxide / cerium dioxide composite; Step 2: reacting chitosan with an organic acid to prepare a water-soluble modified chitosan derivative; Step 3: Mix the nano zinc oxide / cerium dioxide complex and the modified chitosan derivative, then stir and emulsify the aqueous acrylic resin, deionized water and dispersant, and add the mixture into the nano zinc oxide / cerium dioxide complex and the modified chitosan derivative; Step 4: Add the diatomaceous earth-loaded plant essential oil, the plant-derived mildew inhibitor and the photocatalyst into the mixed solution of step 3 and stir to mix, adjust the pH of the mixed solution to 8-9, and filter to obtain the finished product.

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