High-strength impact-resistant antibacterial plastic preservation box and preparation method thereof

Abstract

The invention relates to the technical field of plastic preservation boxes, in particular to a high-strength impact-resistant antibacterial plastic preservation box. Comprising the following raw materials in parts by weight: 70-90 parts of polyethylene resin particles, 5-10 parts of flaky antibacterial aluminum oxide, 1-3 parts of a release agent, 1-2 parts of a defoaming agent and 0.5-1.5 parts of an antioxidant, and the flaky antibacterial aluminum oxide is prepared from the following raw materials in parts by weight: 15-25 parts of flaky nano aluminum oxide, 2-5 parts of dimethyl sulfoxide, 5-10 parts of deionized water, 3-8 parts of ethanol and 1-3 parts of carboxymethyl chitosan. The high-strength impact-resistant antibacterial plastic preservation box disclosed by the invention is durable in use and high in cost performance, achieves the effects of environmental protection, safety, improvement of product quality, reduction of pollution, guarantee of human health and the like, meets the requirements of consumers, and is simple in preparation method, relatively low in bubble generation rate of the preservation box body and suitable for industrial production.

Description

Technical Field

[0001] The present invention relates to the technical field of plastic fresh-keeping boxes, and in particular to a high-strength, impact-resistant and antibacterial plastic fresh-keeping box and a preparation method thereof. Background Art

[0002] With the development of social economy, plastic fresh-keeping boxes are plastic containers made of food-grade plastic raw materials that can be used to carry food when we go out. They are a very common household plastic product in our daily life. They are popular because they are light and portable, and are indispensable plastic containers for picnics or hiking. Plastic fresh-keeping boxes are available in a variety of styles and sizes. At present, existing plastic fresh-keeping boxes can meet most people's living needs. However, after long-term use, bacteria easily breed inside, and bacteria can affect health after entering the human body. In addition, plastic fresh-keeping boxes have the characteristics of light weight, bright and calm surface, good chemical resistance, excellent chemical stability and electrical insulation, and non-toxicity. However, they also have disadvantages such as low impact strength and tensile strength, insufficient rigidity, easy aging, brittleness, easy deformation, and easy cracking, which makes it difficult to meet people's requirements.

[0003] Therefore, it is necessary to provide consumers with a durable, cost-effective, high-strength, impact-resistant and antibacterial plastic food storage box to achieve environmental protection and safety, improve product quality, reduce pollution, protect human health and meet consumer needs. Summary of the Invention

[0004] The purpose of the present invention is to provide a high-strength, impact-resistant and antibacterial plastic fresh-keeping box and a preparation method thereof, so as to solve the problems of the existing plastic fresh-keeping box being prone to bacterial growth, insufficient rigidity and easy aging and deformation after long-term use.

[0005] The present invention provides a high-strength, impact-resistant, and antibacterial plastic fresh-keeping box, comprising the following raw materials in parts by weight: 70-90 parts of polyethylene resin particles 5-10 parts of antibacterial aluminum oxide flakes 1-3 parts release agent 1-2 parts defoaming agent 0.5-1.5 parts of antioxidant.

[0006] Preferably, the flaky antibacterial aluminum oxide is made of the following raw materials in parts by weight: 15-25 parts of flaky nano-alumina 2-5 parts dimethyl sulfoxide 5-10 parts deionized water 3-8 parts ethanol 1-3 parts carboxymethyl chitosan 0.5-2 parts of 2-aminoheptanoic acid 2-4 parts of sodium methoxide.

[0007] Preferably, the antioxidant is 2,6-di-tert-butylphenol. Polypropylene has poor antioxidant capacity and is prone to aging after long-term use. Adding an antioxidant can improve the antioxidant effect of polypropylene and delay the aging of the plastic fresh-keeping box.

[0008] Preferably, the defoaming agent is polydiethylsiloxane. Using polydiethylsiloxane as a defoaming agent can further remove bubbles generated during the processing of the plastic fresh-keeping box.

[0009] Preferably, the release agent is stearamide, and polyethylene resin particles are used as the main component of the plastic fresh-keeping box. Polypropylene has the advantages of high temperature resistance and high strength. When the polymer is processed and molded, there is friction between the molten polymer molecules and friction between the polymer melt and the surface of the processing equipment. The friction will reduce the flow properties of the polymer, and in severe cases will cause overheating and aging of the material. Stearamide has a good lubricating effect and can reduce the friction between the molten polymer molecules and the friction between the polymer melt and the surface of the processing equipment.

[0010] Preferably, the high-strength impact-resistant antibacterial plastic fresh-keeping box has an impact strength of 85-95 J / m2; a molding shrinkage rate of 0.8-1.3%; a bending strength of 55-60 MPa; a tensile strength of 43-48 MPa; an elongation at break of 42%-49%; a heat-resistant temperature of 130-140°C; and a Vicat softening point of 165-175°C.

[0011] Preferably, a method for preparing a high-strength, impact-resistant, antibacterial plastic fresh-keeping box comprises the following steps: Step 1: Dry the polyethylene resin particles and control the moisture content to below 0.1%. First, heat the polyethylene resin particles to remove the moisture in the polyethylene resin, reduce the generation of bubbles during the processing of the plastic fresh-keeping box, and improve the quality of the plastic fresh-keeping box; Step 2: preparing a flaky antibacterial aluminum oxide precursor, and then preparing the flaky antibacterial aluminum oxide precursor into flaky antibacterial aluminum oxide; Step 3: Mix the polyethylene resin particles, the release agent, the defoaming agent, the antioxidant, and the antibacterial alumina flakes and stir them to obtain a mixture; Step 4: Load the mixed materials into the injection molding machine for melting and mixing, send the melt into the mold cavity for molding, and cool and solidify to obtain a high-strength, impact-resistant and antibacterial plastic food storage box.

[0012] Preferably, the preparation method of the flaky antibacterial alumina precursor in step 2 is: mixing flaky nano-alumina, dimethyl sulfoxide and deionized water to form a slurry, heating and stirring, and drying at 100-110°C to obtain flaky nano-alumina powder. The flaky nano-alumina has a toughening effect on the polypropylene plastic fresh-keeping box and improves the impact resistance of the polypropylene plastic fresh-keeping box. The flaky nano-alumina powder is added to half ethanol and ultrasonically oscillated, and the precursor is obtained by centrifugal precipitation and drying.

[0013] Preferably, the method for preparing the flaky antibacterial alumina in step 2 is: adding carboxymethyl chitosan to 2-aminoheptanoic acid, which has a strong antibacterial effect and improves the antibacterial properties of the plastic fresh-keeping box, then adding sodium methoxide as a catalyst, heating and stirring to obtain modified carboxymethyl chitosan, adding the modified carboxymethyl chitosan to the other half of the ethanol solution to prepare a modified carboxymethyl chitosan solution, then adding the flaky antibacterial alumina precursor, stirring the reaction, and obtaining the flaky antibacterial alumina through centrifugal precipitation and drying.

[0014] Preferably, the mass fraction of the ethanol solution is 60-80%.

[0015] The test data of high-strength impact-resistant antibacterial plastic fresh-keeping box are as follows: 1. Sensory organs: normal color, no peculiar smell, no impurities; 2. Soaking liquid: no turbidity, no precipitation, no odor; 3. Total migration (4% acetic acid, 100°C, 2h): <2.0 mg / dm2; 4. Total migration (50% acetic acid, 100°C, 2h): <2.0 mg / dm2; 5. Total migration (isooctane, 60℃, 1.5h): <2.0 mg / dm2; 6. Potassium permanganate consumption (water, 60°C, 1.5h): <2.0 mg / km; 7. Heavy metals (4% acetic acid, 60°C, 2h): <1 mg / km; 8. Dissolution amount in n-hexane (w / w): 0.1%; 9. Dissolution amount in xylene (w / w): 0.5%; 10. Impact strength 85-95J / m2; 11. Molding shrinkage: 0.8-1.3%; 12. Flexural strength 55-60 MPa; 13. Tensile strength 43-48 MPa; 14. Elongation at break 42%-49%; 15. Heat-resistant temperature 130-140℃; 16. Vicat softening point 165-175℃.

[0016] Through the above scheme, it can be seen that the high-strength, impact-resistant and antibacterial plastic fresh-keeping box of the present invention is durable, cost-effective, and achieves environmental protection and safety, improves product quality, reduces pollution, protects human health and other effects, meets the needs of consumers, and the preparation method is simple, the bubble generation rate of the fresh-keeping box body is low, and it is suitable for industrial production. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Example 1

[0018] A high-strength, impact-resistant, and antibacterial plastic fresh-keeping box comprises the following raw materials in parts by weight: 75 parts of polyethylene resin particles 6 parts of antibacterial aluminum oxide flakes 1.5 parts release agent 1 part defoaming agent 0.7 parts of antioxidant.

[0019] The flaky antibacterial aluminum oxide is made of the following raw materials in parts by weight: 17 parts of flake nano-alumina 2.5 parts of dimethyl sulfoxide 6 parts deionized water 4 parts ethanol 1.2 parts of carboxymethyl chitosan 0.7 parts of 2-aminoheptanoic acid 2.3 parts of sodium methoxide.

[0020] The antioxidant is 2,6-di-tert-butylphenol. Polypropylene has poor antioxidant capacity and is prone to aging after long-term use. Adding an antioxidant can improve the antioxidant effect of polypropylene and delay the aging of plastic fresh-keeping boxes.

[0021] The defoaming agent is polydiethylsiloxane, which is used as the defoaming agent to further remove bubbles generated during the processing of the plastic fresh-keeping box.

[0022] The release agent is stearamide, and polyethylene resin particles are used as the main component of the plastic fresh-keeping box. Polypropylene has the advantages of high temperature resistance and high strength. When polymers are processed and molded, there is friction between molten polymer molecules and friction between the polymer melt and the surface of the processing equipment. The friction will reduce the flow properties of the polymer, and in severe cases will cause overheating and aging of the material. Stearamide has a good lubricating effect and can reduce the friction between molten polymer molecules and the friction between the polymer melt and the surface of the processing equipment.

[0023] A method for preparing a high-strength, impact-resistant, and antibacterial plastic fresh-keeping box comprises the following steps: Step 1: Dry the polyethylene resin particles and control the moisture content to below 0.1%. First, heat the polyethylene resin particles to remove the moisture in the polyethylene resin, reduce the generation of bubbles during the processing of the plastic fresh-keeping box, and improve the quality of the plastic fresh-keeping box; Step 2: preparing a flaky antibacterial aluminum oxide precursor, and then preparing the flaky antibacterial aluminum oxide precursor into flaky antibacterial aluminum oxide; Step 3: Mix the polyethylene resin particles, the release agent, the defoaming agent, the antioxidant, and the antibacterial alumina flakes and stir them to obtain a mixture; Step 4: Load the mixed materials into the injection molding machine for melting and mixing, send the melt into the mold cavity for molding, and cool and solidify to obtain a high-strength, impact-resistant and antibacterial plastic food storage box.

[0024] The method for preparing the flaky antibacterial alumina precursor in step 2 is as follows: flaky nano-alumina, dimethyl sulfoxide and deionized water are mixed to form a slurry, heated and stirred, and dried at 100-110°C to obtain flaky nano-alumina powder. The flaky nano-alumina has a toughening effect on the polypropylene plastic fresh-keeping box and improves the impact resistance of the polypropylene plastic fresh-keeping box. The flaky nano-alumina powder is added to half ethanol and ultrasonically oscillated, and the precursor is obtained after centrifugal precipitation and drying.

[0025] The method for preparing the flaky antibacterial alumina in step 2 is as follows: adding carboxymethyl chitosan to 2-aminoheptanoic acid; carboxymethyl chitosan has a strong antibacterial effect and improves the antibacterial performance of the plastic fresh-keeping box; then adding sodium methoxide as a catalyst; heating and stirring to obtain modified carboxymethyl chitosan; adding the modified carboxymethyl chitosan to the other half of the ethanol solution to prepare a modified carboxymethyl chitosan solution; then adding the flaky antibacterial alumina precursor; stirring to react; and obtaining the flaky antibacterial alumina through centrifugal precipitation and drying.

[0026] The mass fraction of the ethanol solution is 60-80%. Example 2

[0027] A high-strength, impact-resistant, and antibacterial plastic fresh-keeping box comprises the following raw materials in parts by weight: 82 parts of polyethylene resin particles 8 parts of antibacterial aluminum oxide flakes 2.2 parts of release agent 1.5 parts defoaming agent 0.9 parts of antioxidant.

[0028] The flaky antibacterial aluminum oxide is made of the following raw materials in parts by weight: 20 parts of flaky nano-alumina 3.5 parts of dimethyl sulfoxide 8 parts deionized water 6 parts of ethanol 2 parts of carboxymethyl chitosan 1.1 parts of 2-aminoheptanoic acid 2.8 parts of sodium methoxide.

[0029] The antioxidant is 2,6-di-tert-butylphenol. Polypropylene has poor antioxidant capacity and is prone to aging after long-term use. Adding an antioxidant can improve the antioxidant effect of polypropylene and delay the aging of plastic fresh-keeping boxes.

[0030] The defoaming agent is polydiethylsiloxane, which is used as the defoaming agent to further remove bubbles generated during the processing of the plastic fresh-keeping box.

[0031] The release agent is stearamide, and polyethylene resin particles are used as the main component of the plastic fresh-keeping box. Polypropylene has the advantages of high temperature resistance and high strength. When polymers are processed and molded, there is friction between molten polymer molecules and friction between the polymer melt and the surface of the processing equipment. The friction will reduce the flow properties of the polymer, and in severe cases will cause overheating and aging of the material. Stearamide has a good lubricating effect and can reduce the friction between molten polymer molecules and the friction between the polymer melt and the surface of the processing equipment.

[0032] A method for preparing a high-strength, impact-resistant, and antibacterial plastic fresh-keeping box comprises the following steps: Step 1: Dry the polyethylene resin particles and control the moisture content to below 0.1%. First, heat the polyethylene resin particles to remove the moisture in the polyethylene resin, reduce the generation of bubbles during the processing of the plastic fresh-keeping box, and improve the quality of the plastic fresh-keeping box; Step 2: preparing a flaky antibacterial aluminum oxide precursor, and then preparing the flaky antibacterial aluminum oxide precursor into flaky antibacterial aluminum oxide; Step 3: Mix the polyethylene resin particles, the release agent, the defoaming agent, the antioxidant, and the antibacterial alumina flakes and stir them to obtain a mixture; Step 4: Load the mixed materials into the injection molding machine for melting and mixing, send the melt into the mold cavity for molding, and cool and solidify to obtain a high-strength, impact-resistant and antibacterial plastic food storage box.

[0033] The method for preparing the flaky antibacterial alumina precursor in step 2 is as follows: flaky nano-alumina, dimethyl sulfoxide and deionized water are mixed to form a slurry, heated and stirred, and dried at 100-110°C to obtain flaky nano-alumina powder. The flaky nano-alumina has a toughening effect on the polypropylene plastic fresh-keeping box and improves the impact resistance of the polypropylene plastic fresh-keeping box. The flaky nano-alumina powder is added to half ethanol and ultrasonically oscillated, and the precursor is obtained after centrifugal precipitation and drying.

[0034] The method for preparing the flaky antibacterial alumina in step 2 is as follows: adding carboxymethyl chitosan to 2-aminoheptanoic acid; carboxymethyl chitosan has a strong antibacterial effect and improves the antibacterial performance of the plastic fresh-keeping box; then adding sodium methoxide as a catalyst; heating and stirring to obtain modified carboxymethyl chitosan; adding the modified carboxymethyl chitosan to the other half of the ethanol solution to prepare a modified carboxymethyl chitosan solution; then adding the flaky antibacterial alumina precursor; stirring to react; and obtaining the flaky antibacterial alumina through centrifugal precipitation and drying.

[0035] The mass fraction of the ethanol solution is 60-80%. Example 3

[0036] A high-strength, impact-resistant, and antibacterial plastic fresh-keeping box comprises the following raw materials in parts by weight: 90 parts of polyethylene resin particles 10 parts of antibacterial aluminum oxide flakes 2.8 parts of release agent 2 parts defoaming agent 1.2 parts of antioxidant.

[0037] The flaky antibacterial aluminum oxide is made of the following raw materials in parts by weight: 23 parts of flaky nano-alumina 4 parts dimethyl sulfoxide 10 parts deionized water 8 parts of ethanol 2.4 parts of carboxymethyl chitosan 1.3 parts of 2-aminoheptanoic acid 3.1 parts of sodium methoxide.

[0038] The antioxidant is 2,6-di-tert-butylphenol. Polypropylene has poor antioxidant capacity and is prone to aging after long-term use. Adding an antioxidant can improve the antioxidant effect of polypropylene and delay the aging of plastic fresh-keeping boxes.

[0039] The defoaming agent is polydiethylsiloxane, which is used as the defoaming agent to further remove bubbles generated during the processing of the plastic fresh-keeping box.

[0040] The release agent is stearamide, and polyethylene resin particles are used as the main component of the plastic fresh-keeping box. Polypropylene has the advantages of high temperature resistance and high strength. When polymers are processed and molded, there is friction between molten polymer molecules and friction between the polymer melt and the surface of the processing equipment. The friction will reduce the flow properties of the polymer, and in severe cases will cause overheating and aging of the material. Stearamide has a good lubricating effect and can reduce the friction between molten polymer molecules and the friction between the polymer melt and the surface of the processing equipment.

[0041] A method for preparing a high-strength, impact-resistant, and antibacterial plastic fresh-keeping box comprises the following steps: Step 1: Dry the polyethylene resin particles and control the moisture content to below 0.1%. First, heat the polyethylene resin particles to remove the moisture in the polyethylene resin, reduce the generation of bubbles during the processing of the plastic fresh-keeping box, and improve the quality of the plastic fresh-keeping box; Step 2: preparing a flaky antibacterial aluminum oxide precursor, and then preparing the flaky antibacterial aluminum oxide precursor into flaky antibacterial aluminum oxide; Step 3: Mix the polyethylene resin particles, the release agent, the defoaming agent, the antioxidant, and the antibacterial alumina flakes and stir them to obtain a mixture; Step 4: Load the mixed materials into the injection molding machine for melting and mixing, send the melt into the mold cavity for molding, and cool and solidify to obtain a high-strength, impact-resistant and antibacterial plastic food storage box.

[0042] The method for preparing the flaky antibacterial alumina precursor in step 2 is as follows: flaky nano-alumina, dimethyl sulfoxide and deionized water are mixed to form a slurry, heated and stirred, and dried at 100-110°C to obtain flaky nano-alumina powder. The flaky nano-alumina has a toughening effect on the polypropylene plastic fresh-keeping box and improves the impact resistance of the polypropylene plastic fresh-keeping box. The flaky nano-alumina powder is added to half ethanol and ultrasonically oscillated, and the precursor is obtained after centrifugal precipitation and drying.

[0043] The method for preparing the flaky antibacterial alumina in step 2 is as follows: adding carboxymethyl chitosan to 2-aminoheptanoic acid; carboxymethyl chitosan has a strong antibacterial effect and improves the antibacterial performance of the plastic fresh-keeping box; then adding sodium methoxide as a catalyst; heating and stirring to obtain modified carboxymethyl chitosan; adding the modified carboxymethyl chitosan to the other half of the ethanol solution to prepare a modified carboxymethyl chitosan solution; then adding the flaky antibacterial alumina precursor; stirring to react; and obtaining the flaky antibacterial alumina through centrifugal precipitation and drying.

[0044] The mass fraction of the ethanol solution is 60-80%.

[0045] The high-strength, impact-resistant, and antibacterial plastic fresh-keeping boxes prepared in Examples 1-3 were subjected to various tests, and the test results are as follows: Table 1: Test results of impact strength, molding shrinkage and flexural strength of various embodiments of the present invention sample Impact strength (J / m2) Molding shrinkage (%) Flexural strength (MPa) Example 1 88 0.9 58 Example 2 93 1 55 Example 3 90 1.1 60 Table 2: Test results of tensile strength, elongation at break, and heat resistance temperature of various embodiments of the present invention sample Tensile strength (MPa) Elongation at break (%) Heat-resistant temperature (℃) Example 1 48 48 132 Example 2 45 43 138 Example 3 44 45 135 Table 3: Performance test results of Vicat softening point, Escherichia coli sterilization rate, and Staphylococcus aureus sterilization rate of various embodiments of the present invention sample Vicat softening point (℃) Escherichia coli sterilization rate (%) Sterilization rate of Staphylococcus aureus (%) Example 1 168 97.8 98.5 Example 2 165 98.1 98.3 Example 3 165 98.3 99.1 From the above test results, it can be seen that the high-strength, impact-resistant and antibacterial plastic fresh-keeping box prepared by the present invention is durable, cost-effective, and achieves environmental protection and safety, improves product quality, reduces pollution, and protects human health, meeting the needs of consumers. In addition, the preparation method is simple, the bubble generation rate of the fresh-keeping box body is low, it is suitable for industrial production, and has good market application prospects.

[0046] The specific embodiments described above further illustrate the technical problems, technical solutions and beneficial effects solved by the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-strength, impact-resistant, antibacterial plastic fresh-keeping box, characterized in that: The composition comprises the following raw materials in parts by weight: 70-90 parts of polyethylene resin particles 5-10 parts of antibacterial aluminum oxide flakes 1-3 parts release agent 1-2 parts defoaming agent 0.5-1.5 parts of antioxidant.

2. A high-strength, impact-resistant, antibacterial plastic fresh-keeping box according to claim 1, characterized in that: The flaky antibacterial aluminum oxide is made of the following raw materials in parts by weight: 15-25 parts of flaky nano-alumina 2-5 parts dimethyl sulfoxide 5-10 parts deionized water 3-8 parts ethanol 1-3 parts carboxymethyl chitosan 0.5-2 parts of 2-aminoheptanoic acid 2-4 parts of sodium methoxide.

3. The high-strength, impact-resistant, antibacterial plastic fresh-keeping box according to claim 1, characterized in that: The antioxidant is 2,6-di-tert-butylphenol.

4. The high-strength, impact-resistant, antibacterial plastic fresh-keeping box according to claim 1, characterized in that: The defoaming agent is polydiethylsiloxane.

5. The high-strength, impact-resistant, antibacterial plastic fresh-keeping box according to claim 1, characterized in that: The release agent is stearamide.

6. The high-strength, impact-resistant, antibacterial plastic fresh-keeping box according to claim 1, characterized in that: The high-strength impact-resistant antibacterial plastic fresh-keeping box has an impact strength of 85-95 J / m2; a molding shrinkage rate of 0.8-1.3%; a bending strength of 55-60 MPa; a tensile strength of 43-48 MPa; an elongation at break of 42%-49%; a heat-resistant temperature of 130-140°C; and a Vicat softening point of 165-175°C.

7. A method for preparing a high-strength, impact-resistant, and antibacterial plastic fresh-keeping box, characterized in that: The following steps are involved: Step 1: Dry the polyethylene resin pellets to control the moisture content below 0.1%; Step 2: preparing a flaky antibacterial aluminum oxide precursor, and then preparing the flaky antibacterial aluminum oxide precursor into flaky antibacterial aluminum oxide; Step 3: Mix the polyethylene resin particles, the release agent, the defoaming agent, the antioxidant, and the antibacterial alumina flakes and stir them to obtain a mixture; Step 4: Load the mixed materials into the injection molding machine for melting and mixing, send the melt into the mold cavity for molding, and cool and solidify to obtain a high-strength, impact-resistant and antibacterial plastic food storage box.

8. The method for preparing a high-strength, impact-resistant, antibacterial plastic fresh-keeping box according to claim 7, characterized in that: The method for preparing the flaky antibacterial alumina precursor in step 2 is as follows: mixing flaky nano-alumina, dimethyl sulfoxide and deionized water to form a slurry, heating and stirring, and drying at 100-110°C to obtain flaky nano-alumina powder; adding the flaky nano-alumina powder to half ethanol and ultrasonically oscillating it, and then centrifuging and drying it to obtain a precursor.

9. The method for preparing a high-strength, impact-resistant, antibacterial plastic fresh-keeping box according to claim 7, characterized in that: The method for preparing the flaky antibacterial alumina in step 2 is as follows: adding carboxymethyl chitosan to 2-aminoheptanoic acid, then adding sodium methoxide as a catalyst, heating and stirring to obtain modified carboxymethyl chitosan, adding the modified carboxymethyl chitosan to the other half of the ethanol solution to prepare a modified carboxymethyl chitosan solution, then adding the flaky antibacterial alumina precursor, stirring to react, and obtaining the flaky antibacterial alumina through centrifugal precipitation and drying.

10. The method for preparing a high-strength, impact-resistant, antibacterial plastic fresh-keeping box according to claim 2, characterized in that: The mass fraction of the ethanol solution is 60-80%.