Four-dimensional water-absorbing antibacterial antioxidant food preservative film and preparation method thereof

Abstract

The invention provides a four-dimensional water-absorbing antibacterial antioxidant food preservative film which comprises a three-chamber eccentric parallel structure nanofiber membrane and a water-absorbing polymer-based nanoparticle layer, the three-chamber eccentric parallel structure nanofiber membrane is formed by a plurality of three-chamber eccentric parallel structure nanofibers, the three-chamber eccentric parallel structure nanofiber comprises an anti-oxidation layer, an antibacterial layer and a nanofiber layer, the antibacterial layer wraps the outer side of the nanofiber layer, the end of the nanofiber layer protrudes out of the end of the antibacterial layer, the anti-oxidation layer wraps the outer side of the antibacterial layer, the end of the antibacterial layer protrudes out of the end of the anti-oxidation layer, and the end of the anti-oxidation layer protrudes out of the end of the anti-oxidation layer. And the water-absorbing polymer-based nanoparticle layer is positioned on the surface of the three-chamber eccentric parallel structure nanofiber membrane. The invention also provides a preparation method of the four-dimensional water-absorbing antibacterial antioxidant food preservative film. The fiber membrane provided by the invention has multiple functions of water absorption, antibiosis, antioxidation and the like, and is a good food preservative film.

Description

Technical Field

[0001] The invention relates to the technical field of food preservation, in particular to a four-dimensional water-absorbing, antibacterial and antioxidant food preservative film and a preparation method thereof. Background Art

[0002] Nanotechnology is developing rapidly. Among them, nanostructure plays a vital role in nanotechnology. A new nanostructure can determine a new nanotechnology (Isaacoff BP, KA Brown. Progress in top-down control of bottom-up assembly. Nano Letters 2017, 17(11), 6508-6510.).

[0003] Nanostructure preparation is generally categorized into two approaches: top-down and bottom-up. However, bottom-up approaches (such as molecular self-assembly) struggle to produce high-purity structures due to difficulties in molecular control, and industrialization is extremely challenging. While top-down approaches can be used to industrially process and produce a variety of nanoproducts, the vast majority of their structural components are uniform, making it difficult to manipulate their distribution and internal multi-compartmental structure. Electrospinning technology, particularly multi-fluid electrospinning, enables the direct, single-step production of a variety of complex nanostructures, such as the three-compartment, parallel-structured nanofibers disclosed in Chinese Invention Patent ZL201611122984.6. This complex, multi-compartmental structure provides a powerful platform for the design and construction of a wider range of multifunctional nanomaterials.

[0004] High-voltage electrostatic spraying technology and high-voltage electrospinning technology are both electrohydrodynamic technologies, which use the interaction between high-voltage static electricity and fluid to quickly atomize droplets and prepare solid micro-nanoparticles (Si Y, Shi S, Hu J.Electrospinning and electrospraying synergism: Twins-tech collaborationacross dimensions. Matter. 2024 Apr 3;7(4):1373-405.). This technology is both an advanced micro-nanotechnology that can be used for the single-step direct preparation of micro-nanostructures and a traditional industrial and agricultural technology that has been used for a long time. For example, high-voltage electrostatic spraying technology is used to spray paint on automobile surfaces, and high-voltage electrostatic spraying is used to spray chemicals and prevent pests and diseases.

[0005] In July 1990, the first International Conference on Nanoscience and Nanotechnology was held in Baltimore, USA, marking the official birth of nanoscience and nanotechnology. By 1999, nanotechnology had begun to enter the market. Over the past 20 years, numerous countries and regions have formulated relevant strategies and plans, invested heavily in seizing strategic positions in nanotechnology, established nanomaterials research centers, and included nanotechnology as a research and development priority in their basic science and technology plans.

[0006] In the prior art, nanotechnology has not yet been applied to the production of food cling film. And the food cling film produced by conventional methods has unsatisfactory water absorption capacity, antibacterial capacity and antioxidant capacity, and its air permeability and mechanical properties are also relatively weak. Summary of the Invention

[0007] In response to the above technical problems in the prior art, the present invention provides a four-dimensional water-absorbing, antibacterial and antioxidant food cling film and a preparation method thereof, which are used to solve the technical problem that the water absorption capacity, antibacterial capacity and antioxidant capacity of the food cling film in the prior art are not ideal.

[0008] The present invention provides a four-dimensional water-absorbing, antibacterial and antioxidant food preservative film, comprising a three-chamber eccentric parallel structure nanofiber membrane and a water-absorbing polymer-based nanoparticle layer. The three-chamber eccentric parallel structure nanofiber membrane is formed by a plurality of three-chamber eccentric parallel structure nanofibers. The three-chamber eccentric parallel structure nanofibers comprise an antioxidant layer, an antibacterial layer and a nanofiber layer. The antibacterial layer is coated on the outside of the nanofiber layer, and the end of the nanofiber layer protrudes from the end of the antibacterial layer. The antioxidant layer is coated on the outside of the antibacterial layer, and the end of the antibacterial layer protrudes from the end of the antioxidant layer. The water-absorbing polymer-based nanoparticle layer is located on the surface of the three-chamber eccentric parallel structure nanofiber membrane, and the water-absorbing polymer-based nanoparticle layer is composed of composite particles of sodium alginate and nano-titanium dioxide.

[0009] The present invention also provides a method for preparing the four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film, which is characterized by comprising an electrospinning process using a high-voltage electrostatic spinning device and an electrospraying process using a high-voltage electrostatic spray device; The electrospinning process using a high-voltage electrospinning device includes the following steps: dissolving cellulose acetate in a solvent consisting of ethanol, acetone, and N,N-dimethylacetamide, stirring to form a uniform polymer solution, then dividing the polymer solution into three parts, adding vitamin E to one of the polymer solutions to form a polymer-vitamin E co-solution solution, and adding sodium benzoate to the other polymer solution to form a polymer-sodium benzoate co-solution solution, and then introducing the polymer-vitamin E co-solution solution, the polymer-sodium benzoate co-solution solution, and the polymer solution into the first syringe, the second syringe, and the third syringe of the three-chamber parallel electrospinning device, respectively, and then starting the high-voltage generator in the three-chamber parallel electrospinning device to prepare a three-chamber eccentric parallel structure nanofiber membrane on the fiber receiving plate in the three-chamber parallel electrospinning device; the conditions are: voltage of 14 kV, flow rates of the simple polymer solution, the polymer-sodium benzoate co-solution solution, and the polymer-vitamin E co-solution solution are all 1.0 mL / h, the particle receiving distance is 20 cm, and the ambient conditions are: temperature between 21-25 degrees Celsius, and humidity between 35-55%; The electrospraying process using a high-voltage electrostatic spray device includes the following steps: dissolving nano-titanium dioxide and sodium alginate in an ethanol aqueous solution, stirring to form a uniform solution, and then performing high-voltage electrostatic spraying on the surface of the three-chamber eccentric parallel structure nanofiber membrane through the high-voltage electrostatic spray device to prepare a water-absorbing polymer-based nanoparticle layer. The water-absorbing polymer-based nanoparticle layer and the three-chamber eccentric parallel structure nanofiber membrane form a four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film; electrospraying conditions: voltage of 18 kilovolts, flow rate of the ethanol aqueous solution of nano-titanium dioxide and sodium alginate of 1.0 mL / h, particle receiving distance of 20 cm, ambient environmental conditions: temperature between 21-25 degrees Celsius, and humidity between 35-55%.

[0010] Furthermore, the volume ratio of ethanol, acetone and N,N-dimethylacetamide is 1:4:1.

[0011] Furthermore, the mass volume ratio of cellulose acetate to ethanol, acetone and N,N-dimethylacetamide solution is 135 g:900 mL.

[0012] Furthermore, the mass ratio of vitamin E to cellulose acetate is 5:135; the mass ratio of sodium benzoate to cellulose acetate is 5:135.

[0013] Furthermore, the mass volume ratio of nano-titanium dioxide and sodium alginate is 1:20, the volume percentage concentration of the ethanol aqueous solution is 40%, the mass volume ratio of nano-titanium dioxide and ethanol aqueous solution is 1 g:400 mL, and the mass volume ratio of sodium alginate and ethanol aqueous solution is 20 g:400 mL.

[0014] The present invention has developed a four-dimensional water-absorbing, antibacterial, and antioxidant food cling film with four-dimensional structural characteristics. The cling film comprises a double-layer structure, one layer of which contains nanofibers with a three-dimensional, parallel structure of three chambers. The other layer is composed of composite particles of sodium alginate and nano-titanium dioxide. Together, these two layers form a four-dimensional cling film. On the one hand, the particles contained in the cling film can rapidly absorb water and swell, providing a contact antibacterial effect. On the other hand, the three-chamber, parallel nanofiber layer is composed of a water-insoluble polymer, which can provide a slow release of antioxidants and antimicrobial active ingredients, while also imparting excellent mechanical properties. Therefore, the fiber film simultaneously possesses multiple functions, including superabsorbency, antibacterial properties, and antioxidant properties, making it an excellent food cling film.

[0015] The four-dimensional, water-absorbing, antibacterial, and antioxidant food wrapping film, featuring a four-dimensional structure, first utilizes a three-fluid parallel eccentric electrospinning technique to create a nanofiber layer. High-voltage electrostatic spraying is then used to apply superabsorbent composite microparticles, using the nanofiber layer as a receiving plate. This allows for the all-in-one controlled production of multiple materials and functional components.

[0016] The four-dimensional structural feature of the present invention refers to a four-dimensional water-absorbing, antibacterial, and antioxidant food wrap containing a double-layer structure, which can be used for food preservation. One layer comprises electrospun nanofibers with a three-dimensional parallel structure. These nanofibers are directly produced in a single step using multi-fluid parallel electrospinning technology and randomly collected to form a nonwoven nanofiber film. The other layer comprises superabsorbent polymer-based nanoparticles, which contain inorganic antibacterial nanoparticles within them. The polymer also possesses superabsorbent properties.

[0017] The polymer-based nanoparticles of the present invention contain inorganic antibacterial nanoparticles, and the polymer has super water-absorbing properties. The particles are prepared by single-step, single-fluid electrospraying a nanosuspension loaded with both the polymer and the nano-inorganic antibacterial component. Three different spinning solutions are simultaneously introduced into a three-chamber parallel spinning head and the voltage is activated. The three spinning solutions are: one is a pure polymer solution, forming a circular cross-sectional structure inside the fiber; one is a co-solvent solution of the polymer and the antibacterial active component, forming a slow-release antibacterial crescent-shaped cross-sectional structure in the middle; and the third is a co-solvent solution of the polymer and the antioxidant, forming a slow-release antioxidant crescent-shaped cross-sectional structure in the outer layer. The structure is then collected by the prepared fiber membrane to form a four-dimensional preservative film. The polymer used in the present invention has super water-absorbing properties, and the nano-inorganic antibacterial component includes various antibacterial inorganic nanoparticles, such as nano-titanium dioxide, nano-zinc oxide, and nano-molybdenum disulfide.

[0018] The polymers used in the present invention are common natural and synthetic polymers, can be used for food packaging, and are insoluble in water; the antibacterial active ingredients and antioxidants include various antibacterial drug molecules and various antioxidants commonly used in the food industry.

[0019] Compared with existing technologies, the present invention offers significant and positive technical benefits. The four-dimensional, water-absorbing, antibacterial, and antioxidant food cling film of the present invention features a two-layer structure, one layer of which is composed of structural nanofibers with a three-chamber, eccentric, parallel structure. This cling film effectively preserves food. The film is produced by integrating cutting-edge nanotechnology with traditional techniques. First, a layer of nanofibers with an internal three-chamber, parallel structure is produced using three-fluid parallel electrospinning technology. Then, an additional layer of particles is deposited on the surface of the fiber membrane using high-voltage electrostatic spraying technology, forming the four-dimensional cling film. The particles are a composite of sodium alginate and nano-titanium dioxide, rapidly absorbing and dissolving, and providing a contact antibacterial effect. The three-chamber, parallel nanofiber layer is composed of a water-insoluble polymer, enabling the slow release of antioxidants and antimicrobial active ingredients while imparting excellent mechanical properties. Consequently, the fiber membrane simultaneously possesses multiple functions, including superabsorbency, antibacterial properties, and antioxidant properties, making it an excellent food cling film. The product of the present invention can be produced on a large scale and used for the application and development of other antibacterial and antioxidant biological products. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the preparation process of the four-dimensional water-absorbing, antibacterial and antioxidant food preservative film of the present invention.

[0021] Figure 2 It is a schematic structural diagram of the four-dimensional water-absorbing, antibacterial and antioxidant food preservative film of the present invention.

[0022] Figure 3 This is a photograph of the process of preparing a three-chamber eccentric parallel structure nanofiber membrane by electrospinning of the present invention.

[0023] Figure 4 This is a picture taken during the electrospraying process of the sodium alginate and nano-titanium dioxide suspension of the present invention.

[0024] Figure 5 This is a picture of the four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film of the present invention.

[0025] Figure 6 This is a scanning electron microscope image of the three-chamber eccentric parallel structure nanofiber prepared by the present invention.

[0026] Figure 7 This is a transmission electron microscope image of the three-chamber eccentric parallel structure nanofiber prepared by the present invention.

[0027] Figure 8 This is a scanning electron microscope image of the sodium alginate and nano-titanium dioxide blended particles prepared in the present invention.

[0028] Figure 9 This is an analysis chart of the in vitro sustained-release of sodium benzoate, an antibacterial active ingredient of the present invention.

[0029] Figure 10 This is an analysis chart of the in vitro sustained release of vitamin E, an antioxidant active ingredient of the present invention. DETAILED DESCRIPTION

[0030] The present invention is further described below with reference to an embodiment. However, the present invention is not limited to these embodiments. Any similar variations of the present invention should be included in the scope of protection of the present invention. The use of directions such as up, down, front, back, left, right, center, inside, and outside in the present invention is only for the convenience of clear description and does not limit the technical solution of the present invention. Example 1:

[0031] like Figure 2 As shown, the present invention provides a four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film, comprising a three-chamber eccentric parallel structure nanofiber membrane 1 and a water-absorbing polymer-based nanoparticle layer 5. The three-chamber eccentric parallel structure nanofiber membrane 1 is formed by a plurality of three-chamber eccentric parallel structure nanofibers, and the three-chamber eccentric parallel structure nanofibers include an antioxidant layer 2, an antibacterial layer 3, and a nanofiber layer 4. The antibacterial layer 3 is coated on the outside of the nanofiber layer 4, and the end of the nanofiber layer 4 protrudes from the end of the antibacterial layer 3. The antioxidant layer 2 is coated on the outside of the antibacterial layer 3, and the end of the antibacterial layer 3 protrudes from the end of the antioxidant layer 2. The water-absorbing polymer-based nanoparticle layer 5 is located on the surface of the three-chamber eccentric parallel structure nanofiber membrane 1, and the water-absorbing polymer-based nanoparticle layer 5 is composed of composite particles of sodium alginate and nano-titanium dioxide.

[0032] Example 2: Process for preparing a four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film The present invention also provides a method for preparing the four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film, comprising an electrospinning process using a high-voltage electrostatic spinning device and an electrospraying process using a high-voltage electrostatic spray device; The three-chamber parallel electrospinning device adopts the high-voltage electrospinning device in the patent with publication number CN106498513B, which includes a first injection pump, a first syringe, a second injection pump, a second syringe, a third injection pump, a third syringe, a fiber receiving plate, a high-voltage generator and a microfluidic control nozzle of a multi-stage eccentric sleeve. The first syringe is installed in the first injection pump, and the first syringe is connected to the microfluidic control nozzle. The second syringe is installed in the second injection pump, and the second syringe is connected to the microfluidic control nozzle through a silicone hose. The third syringe is installed in the third injection pump, and the third syringe is connected to the microfluidic control nozzle through a second silicone hose. The high-voltage generator is connected to the microfluidic control nozzle, and the lower end of the microfluidic control nozzle is provided with a fiber receiving plate; the microfluidic control nozzle of the multi-stage eccentric sleeve The nozzle includes a main capillary, a first curved capillary and a second curved capillary; the cross-section of the outlet end of the main capillary is elliptical; the first curved capillary includes a first straight segment and a first bent portion, the first straight segment is arranged in the main capillary, the outer side wall of the first straight segment is in close contact with the inner side wall of the main capillary, the bent portion of the first curved capillary passes through one side of the main capillary, and the outlet end of the first curved capillary extends out of the outlet end of the main capillary; the second curved capillary includes a second straight segment and a second bent portion, the second straight segment of the second curved capillary is arranged inside the main capillary and passes through the straight segment of the first capillary, extending from the outlet end of the first capillary, the second bent portion passes through the other side of the main capillary, and the outer side wall of the second straight segment is in close contact with the inner side wall of the first straight segment close to the main capillary.

[0033] The high-voltage electrostatic spray device adopts a well-known solution in the prior art, which will not be described in detail here.

[0034] like Figure 1As shown in the left part of , the electrospinning process using a high-voltage electrospinning device includes the following steps: dissolving 135 g of cellulose acetate in 900 mL of ethanol, acetone, and N,N-dimethylacetamide (the volume ratio of ethanol:acetone:N,N-dimethylacetamide is 1:4:1), and stirring to form a uniform polymer solution. The polymer solution is divided into three parts, 5.0g of vitamin E is added to one of the polymer solutions to form a polymer-vitamin E co-solution solution, 5.0g of sodium benzoate is added to the other polymer solution to form a polymer-sodium benzoate co-solution solution, and nothing is added to the other part. Then, the polymer-vitamin E co-solution solution, the polymer-sodium benzoate co-solution solution and the polymer solution are respectively introduced into the first syringe, the second syringe, and the third syringe in the three-chamber parallel electrospinning device (from the inside to the outside, the polymer solution, the polymer-sodium benzoate co-solution solution, and the polymer-vitamin E co-solution solution), and then the high-voltage generator in the three-chamber parallel electrospinning device is started, and the process conditions are adjusted and optimized to prepare a three-chamber eccentric parallel structure nanofiber membrane 1 on the fiber receiving plate in the three-chamber parallel electrospinning device.

[0035] The conditions are: voltage of 14 kV, flow rate of 1.0 mL / h, particle receiving distance (i.e., the distance between the microfluidic control nozzle and the fiber receiving plate in the high-voltage electrospinning device) of 20 cm. Ambient conditions: temperature between 21-25 degrees Celsius, humidity between 35-55%. The process is recorded by camera, as shown in the figure below. Figure 3 As shown, the Taylor cone, straight jet and high-frequency tensile bending are clearly distinguishable.

[0036] like Figure 1 As shown on the right side, the process of electrospraying using a high-voltage electrostatic spray device includes the following steps: dissolving 1g of nano-titanium dioxide and 20g of sodium alginate in 400mL of ethanol aqueous solution (volume percentage concentration of 40%), and stirring to form a uniform solution. Then, high-voltage electrostatic spraying is performed on the surface of the three-chamber eccentric parallel structure nanofiber membrane 1 through a high-voltage electrostatic spray device to prepare a water-absorbing polymer-based nanoparticle layer 5. The water-absorbing polymer-based nanoparticle layer 5 and the three-chamber eccentric parallel structure nanofiber membrane 1 form a four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film; electrospraying conditions: voltage of 18 kV, flow rate of ethanol aqueous solution of nano-titanium dioxide and sodium alginate is 1.0mL / h, and particle receiving distance (i.e., the distance between the outlet of the high-voltage electrostatic spray device and the three-chamber eccentric parallel structure nanofiber membrane 1) is 20cm. Ambient conditions: temperature between 21-25 degrees Celsius, humidity between 35-55%. The process is captured by a camera, as shown in FIG. Figure 4 As shown, the Taylor cone, convergence point and atomization area are clearly distinguishable.

[0037] Example 3: Morphology and structure of electrospun nanofibers and electrosprayed particles The camera shot of the food preservative film of the present invention is as follows Figure 5 As shown. Through gold spraying observation, the morphology of the prepared nanofiber membrane is as follows Figure 6 As shown. Using transmission electron microscopy, the fiber is observed, and its internal structure is as follows Figure 7 The particles were observed using a scanning electron microscope, and their external morphology is shown in Figure 8 shown.

[0038] Example 4: Water absorption and swelling properties of plastic wrap The water absorption capacity of nanofibers was tested in accordance with the pharmaceutical industry standard YY / T 0471.1-2004 of the People's Republic of China. Plastic wrap was cut into 20 mm x 20 mm squares with a thickness of approximately 100-250 μm. The samples were weighed using a balance, and the initial mass was recorded as . The weighed samples were placed in PBS (pH 7.0) phosphate buffer and incubated at 37°C for 24 hours. The samples were collected and gently dried with filter paper to remove excess water. The sample weight at this point was recorded as . The water absorption rate (Q) of the plastic wrap was calculated using the following formula. Six replicates were performed for each sample.

[0039] The results of 6 tests show that the expansion rate of the plastic wrap is 875.2±69.54%. It can be seen that the plastic wrap has good expansion properties. This high absorbency is conducive to quickly absorbing excess water in food.

[0040] Example 5: Mechanical properties test of plastic wrap A sheet of plastic wrap was cut into a 50 mm x 20 mm rectangle. The thickness was measured at three different locations using a micrometer screw, and the average value was taken as the final thickness result. The mechanical properties of the fiber were tested using a microtensile testing machine (Precision Line Vario, Zwick, Germany) at a fixed pulling speed of 1.0 mm / min. The test results are reported as tensile strength, elongation at break, and Young's modulus.

[0041] At the beginning of the stretching process, the fiber membrane gradually stretched and deformed. After a period of time, the stress reached its maximum value, then rapidly decreased, and the fiber membrane completely broke. The test was repeated six times, and the results, expressed as mean ± standard deviation, were 4.57 ± 0.72 MPa, indicating that the nanofiber membrane has good mechanical properties and can meet the basic requirements of food packaging.

[0042] Example 6: In vitro release characteristics of sodium benzoate in plastic wrap According to Example 2, a fresh-keeping film containing only sodium benzoate but no vitamin E was prepared, and the drug dissolution characteristics of the food fresh-keeping film were tested according to the pulp method in the appendix of the Pharmacopoeia of the People's Republic of China. 20g of fresh-keeping film was placed in a phosphate buffer solution with a pH of 7.0. The dissolution effect of sodium benzoate was as follows: Figure 9As shown, cellulose acetate fiber can basically ensure the controlled and slow release of sodium benzoate within nearly 2 days, ensuring a longer-term antibacterial effect.

[0043] Example 7: In vitro release characteristics of vitamin E from plastic wrap According to Example 2, a fresh-keeping film containing only vitamin E but no sodium benzoate was prepared, and the drug dissolution characteristics of the food fresh-keeping film were tested according to the pulp method in the appendix of the Pharmacopoeia of the People's Republic of China. 20g of fresh-keeping film was placed in a phosphate buffer solution with a pH of 7.0. The dissolution effect of vitamin E was as follows: Figure 10 As shown, cellulose acetate fiber can basically ensure the slow release of vitamin E for more than 60 hours, ensuring a longer-term antioxidant effect.

[0044] Example 8: Combinations of different antimicrobial and antioxidant active ingredients According to the process of Examples 1 to 7, a wider range of food preservative films can be prepared by selecting different antimicrobial active ingredients and antioxidant active ingredients for compatibility and combination (all of the above ingredients are food-grade materials), giving the preservative films multiple functions such as water absorption and swelling, antibacterial, and antioxidant. These functions work synergistically to keep food fresh for a longer period of time.

Claims

1. A four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film, characterized in that: The invention comprises a three-chamber eccentric parallel structure nanofiber membrane and a water-absorbing polymer-based nanoparticle layer. The three-chamber eccentric parallel structure nanofiber membrane is formed by a plurality of three-chamber eccentric parallel structure nanofibers. The three-chamber eccentric parallel structure nanofibers comprise an antioxidant layer, an antibacterial layer and a nanofiber layer. The antibacterial layer is coated on the outside of the nanofiber layer, and the end of the nanofiber layer protrudes from the end of the antibacterial layer. The antioxidant layer is coated on the outside of the antibacterial layer, and the end of the antibacterial layer protrudes from the end of the antioxidant layer. The water-absorbing polymer-based nanoparticle layer is located on the surface of the three-chamber eccentric parallel structure nanofiber membrane, and the water-absorbing polymer-based nanoparticle layer is composed of composite particles of sodium alginate and nano-titanium dioxide.

2. A method for preparing the four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film according to claim 1, characterized in that: The method comprises an electrospinning process using a high-voltage electrostatic spinning device and an electrospraying process using a high-voltage electrostatic spraying device; The electrospinning process using a high-voltage electrospinning device includes the following steps: dissolving cellulose acetate in a solvent consisting of ethanol, acetone, and N,N-dimethylacetamide, stirring to form a uniform polymer solution, then dividing the polymer solution into three parts, adding vitamin E to one of the polymer solutions to form a polymer-vitamin E co-solution solution, and adding sodium benzoate to the other polymer solution to form a polymer-sodium benzoate co-solution solution, and then introducing the polymer-vitamin E co-solution solution, the polymer-sodium benzoate co-solution solution, and the polymer solution into the first syringe, the second syringe, and the third syringe of the three-chamber parallel electrospinning device, respectively, and then starting the high-voltage generator in the three-chamber parallel electrospinning device to prepare a three-chamber eccentric parallel structure nanofiber membrane on the fiber receiving plate in the three-chamber parallel electrospinning device; the conditions are: voltage of 14 kV, flow rates of the simple polymer solution, the polymer-sodium benzoate co-solution solution, and the polymer-vitamin E co-solution solution are all 1.0 mL / h, the particle receiving distance is 20 cm, and the ambient conditions are: temperature between 21-25 degrees Celsius, and humidity between 35-55%; The electrospraying process using a high-voltage electrostatic spray device includes the following steps: dissolving nano-titanium dioxide and sodium alginate in an ethanol-water solution, stirring to form a uniform solution, and then performing high-voltage electrostatic spraying on the surface of the three-chamber eccentric parallel structure nanofiber membrane through the high-voltage electrostatic spray device to prepare a water-absorbing polymer-based nanoparticle layer. The water-absorbing polymer-based nanoparticle layer and the three-chamber eccentric parallel structure nanofiber membrane form a four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film; electrospraying conditions: voltage of 18 kilovolts, flow rate of the ethanol-water solution of nano-titanium dioxide and sodium alginate of 1.0 mL / h, particle receiving distance of 20 cm, ambient environmental conditions: temperature between 21-25 degrees Celsius, and humidity between 35-55%.

3. The method for preparing a four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film according to claim 2, characterized in that: The volume ratio of ethanol, acetone and N,N-dimethylacetamide is 1:4:

1.

4. The method for preparing a four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film according to claim 2, wherein: The mass volume ratio of cellulose acetate to ethanol, acetone and N,N-dimethylacetamide solution is 135 g:900 mL.

5. The method for preparing a four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film according to claim 2, characterized in that: The mass ratio of vitamin E to cellulose acetate is 5:135; the mass ratio of sodium benzoate to cellulose acetate is 5:

135.

6. The method for preparing a four-dimensional water-absorbing, antibacterial, and antioxidant food preservative film according to claim 2, characterized in that: The mass volume ratio of nano-titanium dioxide and sodium alginate is 1:20, the volume percentage concentration of the ethanol aqueous solution is 40%, the mass volume ratio of nano-titanium dioxide and ethanol aqueous solution is 1g:400 mL, and the mass volume ratio of sodium alginate and ethanol aqueous solution is 20g:400 mL.

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