Antibacterial porous film and preparation method thereof

Abstract

The invention relates to the field of antibacterial porous films, in particular to an antibacterial porous film and a preparation method thereof. The antibacterial porous film is characterized in that the antibacterial porous film comprises a film carrier and a porous nano coating layer coating the surface of the film carrier, and the porous nano coating layer comprises ZIF nanocrystals of a porous structure. The ZIF nanocrystal with the porous structure is used as a main material of the coating structure, and the ZIF material constructs a porous layer on the surface of the film carrier, so that the antibacterial property of the film can be effectively improved. The structure not only increases the surface area of the film and is beneficial to contact with microorganisms, but also contributes to diffusion of substances by virtue of the porous structure, so that the antibacterial effect is further enhanced.

Description

Technical Field

[0001] The invention relates to the field of antibacterial porous films, and in particular to an antibacterial porous film and a preparation method thereof. Background Art

[0002] Antibacterial porous film is an emerging material that has attracted widespread attention due to its excellent antibacterial properties and wide application potential. This film is usually composed of polymers, inorganic materials or a composite material of the two, and has a nano-scale porous structure, which makes it excellent in gas and liquid permeability and can effectively block the spread of bacteria and other microorganisms. However, the existing preparation technology still has some defects, which restricts its promotion in practical applications.

[0003] First of all, traditional preparation methods often face the problems of complex processes and high costs. For example, although the solution casting method can obtain a uniform film, it requires a large amount of organic solvents, which poses great environmental pollution and safety risks; while hot pressing molding requires high temperature and high pressure conditions, which is difficult to mass produce. In the design of porous structures, existing preparation technologies often find it difficult to achieve ideal porosity and pore size distribution, which has an adverse effect on the air permeability and filtration efficiency of the film. Too large a pore size may allow bacteria to penetrate, while too small a pore size may restrict the passage of gas and liquid, thereby reducing the application value of the material.

[0004] In response to the above-mentioned prior art, the inventors found that adjusting the morphology of zeolite imidazole framework (ZIF) crystal nanomaterials can effectively prepare thin film materials with good antibacterial properties. However, since the morphology of ZIF nanocrystals cannot be controlled in the actual production process, the simple preparation scheme results in poor nano-roughness of ZIF nanocrystals in antibacterial porous films, which restricts their good antibacterial properties. Summary of the invention

[0005] Based on the technical problems existing in the above-mentioned prior art, the present invention provides an antibacterial porous film and a preparation method thereof.

[0006] In a first aspect, the present application provides an antibacterial porous film, which adopts the following technical solution: An antibacterial porous film, characterized in that it comprises a film carrier and a porous nano-coating layer coated on the surface of the film carrier, wherein the porous nano-coating layer comprises ZIF nano-crystals with a porous structure.

[0007] Through the above technical solution, the present application uses porous ZIF nanocrystals as the main material of the coating structure. Since the ZIF material constructs a porous layer on the surface of the film carrier, the antibacterial performance of the film can be effectively improved. This structure not only increases the surface area of ​​the film, which is conducive to contact with microorganisms, but also the porous structure helps the diffusion of substances, further enhancing the antibacterial effect.

[0008] Furthermore, the porous ZIF nanocrystals are grown from a ZIF synthesis solution, and the ZIF synthesis solution includes the following substances in parts by weight: 3-8 parts of zinc nitrate hexahydrate; 25-40 parts of methylimidazole solution; Co-solvent 0-25 parts; The co-solvent includes at least one of methanol, DMF and water.

[0009] Through the above technical scheme, the present application optimizes the synthesis components of ZIF nanocrystals, because the formation of ZIF nanocrystals depends on the composition of ZIF synthesis solution, wherein zinc nitrate hexahydrate and methylimidazole are key raw materials, providing zinc ions and imidazole ligands respectively. The introduction of co-solvent can adjust the properties of the solution, thereby affecting the crystal growth process of ZIF. By controlling the ratio of each component, the morphology and structural characteristics of ZIF nanocrystals can be adjusted, further improving the antibacterial effect and other physicochemical properties of the film. In addition, the optimization of synthesis conditions can improve the crystallinity and porosity of ZIF, which is crucial for improving the performance of the film.

[0010] In a second aspect, the present application provides a method for preparing an antibacterial porous film, using the following technical solution: A method for preparing an antibacterial porous film comprises the following steps: Take the ZIF synthesis solution, stir and mix it, and perform aging treatment. After the aging treatment, collect the synthesis solution, immerse the thin film carrier in the synthesis solution for primary growth, and dry the thin film carrier; The dried film carrier is taken and placed in the ZIF synthesis solution again for secondary growth; After the growth is completed, the antibacterial porous film can be prepared after washing and drying.

[0011] Through the above technical scheme, the present application promotes ZIF crystals to form in solution through stirring and aging treatment, and then immerses the film carrier in a synthetic solution for a growth. This process is a way of combining physical adsorption with chemical reaction, so that ZIF crystals gradually adhere to the film surface. The regrowth after drying treatment helps to form a more uniform and dense ZIF layer, which improves the antibacterial effect and mechanical strength of the film. The key to this method is the control of temperature, time and growth number, which directly affects the quality of ZIF nanocrystals and the final performance of the film. Therefore, this method provides an effective way for preparing an antibacterial film with excellent performance.

[0012] Furthermore, the film carrier is a porous nylon film.

[0013] Furthermore, the temperature of the primary growth and the secondary growth is 10-80°C.

[0014] Through the above technical scheme, the present application optimizes the temperature range (10-80°C) for primary growth and secondary growth. Temperature is an important parameter that affects the chemical reaction rate and crystal growth. During the synthesis process, a suitable temperature can accelerate the growth of ZIF crystals while inhibiting the formation of irregular crystals. Too low a temperature may result in a too slow reaction rate and an inability to form an ideal porous structure, while too high a temperature may result in excessive growth or degradation of the crystals. Therefore, by controlling within the range of 10-80°C, the growth rate and morphology (leaf-shaped and leaf-shaped cross-morphology) of ZIF can be effectively adjusted to optimize the antibacterial properties and physicochemical properties of the film. The design of this technical scheme provides an important temperature control strategy for obtaining high-performance antibacterial films, ensuring the effective growth of ZIF and the stable performance of the film.

[0015] Furthermore, the volume percentage of the co-solvent is preferably 0-25%.

[0016] Through the above technical scheme, the application optimizes the addition ratio of co-solvents, and co-solvents can change the polarity and solubility of the solution, thereby affecting the growth rate and morphology of ZIF crystals. Suitable co-solvent combinations can promote the rapid crystallization of ZIF and improve the quality and uniformity of crystals. By adjusting the ratio of co-solvents, the porous structure of ZIF can be optimized, thereby improving the antibacterial properties of the film. Specifically, the selection and ratio of co-solvents such as methanol, DMF and water will directly affect the solubility and aggregation behavior of ZIF. Therefore, this claim provides flexible adjustment means in the preparation process to ensure the performance and application effect of the final product.

[0017] In summary, this application has the following beneficial effects: First, the present application uses porous ZIF nanocrystals as the main material of the coating structure. Since the ZIF material constructs a porous layer on the surface of the film carrier, the antibacterial properties of the film can be effectively improved. This structure not only increases the surface area of ​​the film, which is conducive to contact with microorganisms, but also the porous structure helps the diffusion of substances, further enhancing the antibacterial effect.

[0018] Second, the present application optimizes the synthesis components of ZIF nanocrystals, because the formation of ZIF nanocrystals depends on the composition of ZIF synthesis solution, wherein zinc nitrate hexahydrate and methylimidazole are key raw materials, providing zinc ions and imidazole ligands respectively. The introduction of co-solvent can adjust the properties of the solution, thereby affecting the crystal growth process of ZIF. By controlling the ratio of each component, the morphology and structural characteristics of ZIF nanocrystals can be adjusted, further improving the antibacterial effect and other physicochemical properties of the film. In addition, the optimization of synthesis conditions can improve the crystallinity and porosity of ZIF, which is crucial for improving the performance of the film.

[0019] Third, the present application optimizes the temperature range (10-80°C) for primary growth and secondary growth. Temperature is an important parameter that affects the rate of chemical reactions and crystal growth. During the synthesis process, a suitable temperature can accelerate the growth of ZIF crystals while inhibiting the formation of irregular crystals. Too low a temperature may result in a slow reaction rate and an inability to form an ideal porous structure, while too high a temperature may result in excessive growth or degradation of the crystals. Therefore, by controlling the temperature within the range of 10-80°C, the growth rate and morphology (leaf-shaped and leaf-shaped cross-morphology) of ZIF can be effectively adjusted to optimize the antibacterial properties and physicochemical properties of the film. The design of this technical solution provides an important temperature control strategy for obtaining high-performance antibacterial films, ensuring the effective growth of ZIF and the stable performance of the film. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a SEM image of ZIF prepared in Example 1 of the present application using 50% v / v methanol as a co-solvent. DETAILED DESCRIPTION

[0021] The present application is further described in detail below with reference to the embodiments.

[0022] In the examples of the present application, the raw materials and instruments used are as follows, but not limited thereto. Raw materials not otherwise specified are of analytical grade.

[0023] Materials: Nylon membrane (47 mm ø, 0.45 μm pore size, hydrophilic) was purchased from Merck.

[0024] 2-Methylimidazole (Hmim; 99%), Sigma-Aldrich Company Ltd. Zinc nitrate hexahydrate (Zn(NO3)2·6H2O; 98%) Alfa Aesar.

[0025] Ethanol (99.8%) Fisher Scientific UK Ltd. Preparation Example 1 300 g of zinc nitrate hexahydrate, 2500 g of methylimidazole solution and 1000 g of deionized water were mixed to prepare a ZIF synthesis solution 1.

[0026] Preparation Example 2 500 g of zinc nitrate hexahydrate, 3200 g of methylimidazole solution and 1000 g of DMF were mixed to prepare a ZIF synthesis solution 2.

[0027] Preparation Example 3 800 g of zinc nitrate hexahydrate, 4000 g of methylimidazole solution and 1000 g of methanol were mixed to prepare a ZIF synthesis solution 3.

[0028] Example 1 An antibacterial porous film comprises a nylon film carrier and a porous nano coating layer coated on the surface of the film carrier.

[0029] An antibacterial porous film comprises the following preparation steps: The ZIF synthesis solution 3 was aged for 15 min at a stirring speed of 500 rpm, and the synthesis solution was collected after the aging treatment; The nylon film carrier was immersed in the synthetic solution at 10°C for 15 minutes for a growth process, and the film carrier was placed at 60°C for a drying process for 15 minutes; The dried film support was taken and placed in a 10°C ZIF synthesis solution for 30 min for secondary growth. After the growth is completed, the film is washed with deionized water and dried vertically at room temperature for 12 hours to prepare an antibacterial porous film.

[0030] Example 2 An antibacterial porous film comprises a nylon film carrier and a porous nano coating layer coated on the surface of the film carrier.

[0031] An antibacterial porous film comprises the following preparation steps: The ZIF synthesis solution 3 was aged for 15 min at a stirring speed of 500 rpm, and the synthesis solution was collected after the aging treatment; The nylon film carrier was immersed in the synthetic solution at 30°C for 15 minutes for a growth process, and the film carrier was placed at 60°C for a drying process for 15 minutes; The dried film carrier was taken and placed in the 30°C ZIF synthesis solution for 30 min for secondary growth; After the growth is completed, the film is washed with deionized water and dried vertically at room temperature for 12 hours to prepare an antibacterial porous film.

[0032] Example 3 An antibacterial porous film comprises a nylon film carrier and a porous nano coating layer coated on the surface of the film carrier.

[0033] An antibacterial porous film comprises the following preparation steps: The ZIF synthesis solution 3 was aged for 15 min at a stirring speed of 500 rpm, and the synthesis solution was collected after the aging treatment; The nylon film carrier was immersed in the synthetic solution at 80°C for 15 minutes for a growth process, and the film carrier was placed at 60°C for a drying process for 15 minutes; The dried film carrier was taken and placed in 80°C ZIF synthesis solution for 30 min for secondary growth; After the growth is completed, the film is washed with deionized water and dried vertically at room temperature for 12 hours to prepare an antibacterial porous film.

[0034] Example 4 An antibacterial porous film comprises a nylon film carrier and a porous nano coating layer coated on the surface of the film carrier.

[0035] An antibacterial porous film comprises the following preparation steps: The ZIF synthesis solution 2 was aged for 15 min at a stirring speed of 500 rpm, and the synthesis solution was collected after the aging treatment; The nylon film carrier was immersed in the synthetic solution at 30°C for 15 minutes for a growth process, and the film carrier was placed at 60°C for a drying process for 15 minutes; The dried film carrier was taken and placed in the 30°C ZIF synthesis solution for 30 min for secondary growth; After the growth is completed, the film is washed with deionized water and dried vertically at room temperature for 12 hours to prepare an antibacterial porous film.

[0036] Example 5 An antibacterial porous film comprises a nylon film carrier and a porous nano coating layer coated on the surface of the film carrier.

[0037] An antibacterial porous film comprises the following preparation steps: The ZIF synthesis solution 1 was aged for 15 min under a stirring speed of 500 rpm, and the synthesis solution was collected after the aging treatment; The nylon film carrier was immersed in the synthetic solution at 30°C for 15 minutes for a growth process, and the film carrier was placed at 60°C for a drying process for 15 minutes; The dried film carrier was taken and placed in the 30°C ZIF synthesis solution for 30 min for secondary growth; After the growth is completed, the film is washed with deionized water and dried vertically at room temperature for 12 hours to prepare an antibacterial porous film.

[0038] Performance Testing The antibacterial porous films prepared in Examples 1-5 were subjected to antibacterial tests in accordance with GB / T31402-2015. The results are shown in Table 1 below: Table 1 Performance test table

[0039] From the above examples 1-5, combined with Table 1 and Figure 1 By comparing the test results, we can find that: The present application uses porous ZIF nanocrystals as the main material of the coating structure. Since the ZIF material constructs a porous layer on the surface of the film carrier, the antibacterial properties of the film can be effectively improved. This structure not only increases the surface area of ​​the film, which is conducive to contact with microorganisms, but also the porous structure helps the diffusion of substances, further enhancing the antibacterial effect.

[0040] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

[0041] All publications, patent applications, patents and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings conventionally understood by those skilled in the art. In the event of a conflict, the definition in this specification shall prevail.

[0042] When this specification uses the prefix "well-known to those skilled in the art", "prior art" or similar terms to introduce materials, substances, methods, steps, devices or components, etc., the objects introduced by the prefix cover those commonly used in the art when this application is filed, but also include those that are not commonly used at present but will become recognized in the art as being suitable for similar purposes.

[0043] In the context of the present specification, any matters or items not mentioned are directly applicable to those known in the art without any changes except those explicitly stated.

Claims

1. An antibacterial porous film, characterized in that: The invention comprises a film carrier and a porous nano coating layer coated on the surface of the film carrier, wherein the porous nano coating layer comprises ZIF nano crystals with a porous structure.

2. The antibacterial porous film according to claim 1, characterized in that: The porous ZIF nanocrystals are grown from a ZIF synthesis solution, wherein the ZIF synthesis solution comprises the following substances in parts by weight: 3-8 parts of zinc nitrate hexahydrate; 25-40 parts of methylimidazole solution; Co-solvent 0-25 parts; The co-solvent includes at least one of methanol, DMF and water.

3. A method for preparing an antibacterial porous film according to any one of claims 1 to 2, characterized in that: The method comprises the following preparation steps: Take the ZIF synthesis solution, stir and mix it, and perform aging treatment. After the aging treatment, collect the synthesis solution, immerse the thin film carrier in the synthesis solution for primary growth, and dry the thin film carrier; The dried film carrier is taken and placed in the ZIF synthesis solution again for secondary growth; After the growth is completed, the antibacterial porous film can be prepared after washing and drying.

4. The method for preparing an antibacterial porous film according to claim 3, characterized in that: The film carrier is a porous nylon film.

5. The method for preparing an antibacterial porous film according to claim 3, characterized in that: The temperature of the primary growth and the secondary growth is 10-80°C.

6. The method for preparing an antibacterial porous film according to claim 3, characterized in that: The volume percentage of the co-solvent is preferably 0-25%.

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