Degradable high-oxygen-barrier composite film, and preparation method and application thereof

Abstract

The application discloses a degradable high-oxygen-barrier composite film and a preparation method and application thereof. The composite film is composed of polylactic acid and hybrid graphene oxide, wherein the hybrid graphene oxide is connected in a 'face-to-edge' mode by boric acidized graphene oxide and hydroxylated graphene oxide, and the mass percentage of the hybrid graphene oxide in the composite film is 0.25-1 wt%. The prepared composite film has the advantages of degradability and excellent oxygen barrier property, and has a good application background in the packaging field.

Description

Technical Field

[0001] This invention belongs to the field of polymer nanocomposite membranes, specifically relating to a biodegradable high oxygen barrier composite membrane, its preparation method, and its application. Background Technology

[0002] Traditional petroleum-based polymer barrier materials are widely used in the packaging industry due to their advantages such as good flexibility, ease of processing, light weight, and low cost. However, these materials are difficult to degrade in the natural environment, and the large amount of waste packaging materials generated in engineering projects are usually disposed of by incineration or landfill, resulting in significant carbon emissions. At the same time, microplastics entering the natural world seriously harm the environment and ecosystems. With the increasing global emphasis on sustainable development goals and the advocacy of a low-carbon circular economy, polymers with degradable properties have gradually become a focus of research and application.

[0003] Polylactic acid (PLA) is a bio-based polymer produced from renewable biological resources (such as corn and sugarcane). It can be degraded in the natural environment through microbial action, exhibiting excellent biodegradability. As a green and environmentally friendly material, PLA can effectively alleviate the environmental pollution problems caused by traditional petroleum-based polymers and significantly reduce dependence on petroleum resources, making it one of the materials with broad industrial application prospects. However, pure PLA has certain shortcomings in gas barrier properties, limiting its application and development in packaging fields with high barrier requirements. Therefore, improving the gas barrier properties of PLA is key to promoting its widespread application.

[0004] Graphene oxide (GO), as a two-dimensional nanomaterial, is an ideal filler for enhancing the barrier properties of polymers due to its excellent barrier properties, ultra-high aspect ratio, and ease of modification. However, GO tends to aggregate in polymers, limiting its ability to strengthen polymer barrier properties. Typically, hydrophobic modification of GO's surface epoxy groups or edge carboxyl groups (common modifiers include dodecylamine and polyethylene glycol) is used to enhance its dispersibility, thereby improving the barrier properties of composite materials. However, traditional techniques have limited effectiveness in improving the dispersibility of GO in polymers. Besides the surface chemical properties of GO, its topological structure is another important factor affecting its dispersibility. Therefore, further research is needed to improve the dispersibility of GO in polymers and thus enhance the barrier properties of polymers. Summary of the Invention

[0005] In order to overcome the problems of environmental pollution and low oxygen barrier performance of existing oxygen barrier membranes, the primary objective of this invention is to provide a biodegradable high oxygen barrier composite membrane.

[0006] Hybrid GO, which is efficiently assembled by the click chemistry reaction of boric acid and hydroxyl groups in a "face-to-edge" connection mode, has a three-dimensional structure. It can not only effectively suppress the tight packing between the layers through the steric hindrance effect, thereby improving its dispersibility in the polymer, but also extend the diffusion path of gas molecules in multiple dimensions. The combined effect of these two factors can further enhance the barrier properties of the polymer, and significantly enhance the barrier properties of PLA at low filler content (≤1wt%).

[0007] The B-pGO@OH-eGO / PLA composite oxygen barrier membrane of the present invention can effectively solve the problem of poor barrier properties of current biodegradable packaging films.

[0008] Another object of the present invention is to provide a method for preparing the above-mentioned biodegradable high oxygen barrier composite membrane.

[0009] Another object of the present invention is to provide an application of the above-mentioned biodegradable high oxygen barrier composite membrane.

[0010] The objective of this invention is achieved through the following technical solution:

[0011] A biodegradable high oxygen barrier composite membrane is composed of biodegradable PLA and hybrid graphene oxide (B-pGO@OH-eGO).

[0012] The hybrid graphene oxide is a three-dimensional structure formed by connecting graphene oxide in a "face-to-edge" manner; the hybrid graphene oxide accounts for 0.25 to 1 wt% of the composite film by mass.

[0013] The B-pGO@OH-eGO is produced by first introducing boric acid groups onto the graphene oxide surface through a ring-opening reaction between the epoxy groups on the graphene oxide surface and the amino groups in 4-aminophenylboronic acid, resulting in B-pGO. Then, an amidation reaction is performed between the carboxyl groups at the graphene oxide edge and the amino groups in tris(hydroxymethyl)aminomethane to introduce 1,3-dihydroxy groups into the graphene oxide edge, resulting in OH-eGO. Finally, based on a click chemistry reaction between boric acid and hydroxyl groups, B-pGO and OH-eGO are assembled into B-pGO@OH-eGO in a "face-to-edge" connection manner. The graphene oxide is a single-layer sheet of graphene oxide (GO) with a sheet diameter of 50 nm to 5 μm.

[0014] The hybrid graphene oxide (B-pGO@OH-eGO) is obtained by a click chemical reaction of B-pGO and OH-eGO in a mass ratio of 1:2 to 2:1. The B-pGO is obtained by reacting graphene oxide with 4-aminophenylboronic acid in a mass ratio of 1:4 to 10. The OH-eGO is obtained by reacting graphene oxide with a carboxyl activator, followed by reacting it with tris(hydroxymethyl)aminomethane in a mass ratio of graphene oxide to tris(hydroxymethyl)aminomethane of 1:2 to 6.

[0015] The above-mentioned method for preparing a biodegradable high oxygen barrier composite membrane includes the following steps:

[0016] (1) Graphene oxide was dispersed in water, 4-aminophenylboronic acid was added and the pH was adjusted. After the reaction was carried out at room temperature, the boronized graphene oxide (B-pGO) was obtained by filtration, washing with water and drying.

[0017] (2) Graphene oxide is dispersed in an organic solvent, a carboxyl activator is added and reacted at room temperature, then tris(hydroxymethyl)aminomethane is added and heated to react. After filtration, washing with water and drying, hydroxylated graphene oxide (OH-eGO) is obtained.

[0018] (3) Mix and disperse B-pGO and OH-eGO in water, adjust the pH and react, then filter, wash with water and dry to obtain B-pGO@OH-eGO;

[0019] (4) Disperse B-pGO@OH-eGO in ethanol, and obtain B-pGO@OH-eGO chloroform dispersion by chloroform replacement. Then add PLA and mix evenly to obtain film-forming solution. Demold and solidify to obtain biodegradable oxygen barrier film.

[0020] Preferably, the graphene oxide described in steps (1) and (2) is a single-layer sheet graphene oxide (GO) with a sheet diameter of 50 nm to 5 μm.

[0021] Preferably, the mass ratio of 4-aminophenylboronic acid and graphene oxide in step (1) is 4 to 10:1, more preferably 5:1.

[0022] Preferably, the pH adjustment range in step (1) is 7 to 9, more preferably 7 to 8.

[0023] Preferably, the reaction time at room temperature in step (1) is 24 to 48 hours, more preferably 24 to 36 hours.

[0024] Preferably, the carboxyl activator in step (2) is N-hydroxysuccinimide (NHS) and 1-ethyl-(3-dimethylaminopropyl) (EDC); the mass ratio of the carboxyl activator NHS, EDC and GO is 0.5-2:0.5-2:1, more preferably 1:1:1.

[0025] Preferably, the reaction time at room temperature in step (2) is 0.5 to 1 hour.

[0026] Preferably, the mass ratio of trihydroxymethylaminomethane to GO in step (2) is 2 to 6:1, more preferably 3:1.

[0027] Preferably, the temperature of the heating reaction in step (2) is 50-70°C, more preferably 60°C; and the reaction time is 4-12 hours, more preferably 6-10 hours.

[0028] Preferably, the organic solvent in step (2) is dimethylformamide (DMF).

[0029] Preferably, the mass ratio of B-pGO and OH-eGO in step (3) is 1:2 to 2:1.

[0030] Preferably, the pH adjustment in step (3) is 7-8, more preferably 7.3-7.5.

[0031] Preferably, the reaction temperature in step (3) is room temperature; the reaction time is 8 to 18 hours, more preferably 10 to 18 hours.

[0032] Preferably, the concentrations of the dispersions obtained by dispersing graphene oxide in water in step (1), the dispersions obtained by dispersing graphene oxide in an organic solvent in step (2), and the dispersions obtained by mixing B-pGO and OH-eGO in water in step (3) are 1–2 mg / mL, more preferably 1–1.5 mg / mL. Preferably, the mass concentration of B-pGO@OH-eGO in chloroform in step (4) is 0.2–0.5 mg / mL, more preferably 0.375 mg / mL.

[0033] Preferably, the mass ratio of B-pGO@OH-eGO and PLA in step (4) is 2-5:500-800; more preferably, it is 3.75:500.

[0034] Preferably, the film-forming liquid in step (4) is first surface-cured at room temperature for 24-48 hours, more preferably 24-36 hours, and then dried at 30-55°C for 6-8 hours.

[0035] The above-mentioned application of a biodegradable high oxygen barrier composite membrane.

[0036] Preferably, the biodegradable high oxygen barrier composite film is used in the packaging field.

[0037] The core principle of this invention is that the modified GO is efficiently assembled in a "face-to-edge" connection manner based on the click chemical reaction of boric acid and hydroxyl groups, forming a hybrid GO with a three-dimensional structure. This structure can not only effectively suppress the tight packing between the layers through steric hindrance, thereby improving its dispersibility in the polymer, but also extend the diffusion path of gas molecules in multiple dimensions. The combined effect of these two factors can further enhance the barrier properties of the polymer, achieving a significant enhancement of PLA's barrier properties at low filler content (≤1wt%).

[0038] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0039] (1) The high oxygen barrier composite membrane provided by the present invention is biodegradable. Compared with traditional petroleum-based polymer membranes, it can effectively alleviate the pollution problems caused by traditional petroleum-based polymers and the dependence on petroleum resources, and help the implementation of my country's "dual carbon" plan.

[0040] (2) The present invention uses B-pGO@OH-eGO as filler to prepare PLA composite membrane, which can maximize the dispersibility of GO and extend the gas molecule permeation path in multiple dimensions, thus exhibiting excellent barrier performance. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the reaction process between graphene oxide and 4-aminophenylboronic acid.

[0042] Figure 2 This is a schematic diagram of the reaction process between carboxylated graphene oxide and tris(hydroxymethyl)aminomethane.

[0043] Figure 3 This is a schematic diagram of the reaction process between B-pGO and OH-eGO.

[0044] Figure 4 Example 1B-pGO L @OH-eGO L Infrared spectrum of (mass ratio 1:1). Detailed Implementation

[0045] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0046] Unless otherwise specified in the embodiments of this invention, the conditions shall be performed according to conventional conditions or conditions recommended by the manufacturer. All raw materials and reagents used, unless otherwise specified, are commercially available conventional products.

[0047] Example 1

[0048] 40mg GO L(Graphene oxide with a sheet diameter of 500 nm to 1 μm) was placed in 40 mL of deionized water and sonicated for 1 h; 200 mg of 4-aminophenylboronic acid was added, and the pH was adjusted to 7.0 with phosphate buffer solution. The mixture was stirred at room temperature (300 rpm) for 24 h; after filtration, it was washed three times with deionized water and dried to obtain boronized graphene oxide (B-pGO). L ); Take another 40mg GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm) was placed in 40 mL of DMF and sonicated for 1 h. Then, 40 mg each of EDC and NHS were added, and the mixture was stirred at room temperature (300 rpm) for 1 h. Subsequently, 120 mg of tris(hydroxymethyl)aminomethane was added, and the mixture was stirred at 60 °C (300 rpm) for 6 h. After filtration, the mixture was washed three times with deionized water and dried to obtain hydroxylated modified graphene oxide (OH-eGO). L Take 15mg of B-pGO. L Added to 10 mL of deionized water and sonicated for 1 hour, β-pGO was obtained. L Dispersion (concentration 1.5 mg / mL); OH-eGO was prepared using the same method. L Dispersion (OH-eGO) L (Concentration is 1.5 mg / mL). OH-eGO L Adding B-pGO to the dispersion droplets L The pH of the dispersion was adjusted to 7.3 with phosphate buffer solution, and the mixture was stirred at room temperature (300 rpm) for 18 hours. After filtration, the mixture was washed three times with deionized water and dried to obtain hybrid graphene oxide (B-pGO). L @OH-eGO L (mass ratio 1:1)

[0049] Example 2

[0050] 40mg GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm) was placed in 40 mL of deionized water and sonicated for 1 h; 200 mg of 4-aminophenylboronic acid was added, and the pH was adjusted to 8.0 with phosphate buffer solution. The mixture was stirred at room temperature (300 rpm) for 36 h; after filtration, it was washed three times with deionized water and dried to obtain boronized graphene oxide (B-pGO). L ); Take another 40mg GO L(Graphene oxide with a sheet diameter of 500 nm to 1 μm) was placed in 40 mL of DMF and sonicated for 1 h. Then, 20 mg each of EDC and NHS were added, and the mixture was stirred at room temperature (300 rpm) for 1 h. Subsequently, 80 mg of tris(hydroxymethyl)aminomethane was added, and the mixture was stirred at 70 °C (300 rpm) for 5 h. After filtration, the mixture was washed three times with deionized water and dried to obtain hydroxylated modified graphene oxide (OH-eGO). L Take 20mg of B-pGO. L Added to 10 mL of deionized water and sonicated for 1 hour, β-pGO was obtained. L (Concentration of 2 mg / mL); OH-eGO was prepared using the same method. L Dispersion (OH-eGO) L (Concentration is 1 mg / mL). OH-eGO L Adding B-pGO to the dispersion droplets L The pH of the dispersion was adjusted to 8 with phosphate buffer solution, and the mixture was stirred at room temperature (300 rpm) for 8 hours. After filtration, the mixture was washed three times with deionized water and dried to obtain hybrid graphene oxide (B-pGO). L @OH-eGO L (mass ratio 2:1)

[0051] Example 3

[0052] 30mg GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm) was placed in 20 mL of deionized water and sonicated for 1 h; 120 mg of 4-aminophenylboronic acid was added, and the pH was adjusted to 9.0 with phosphate buffer solution. The mixture was stirred at room temperature (300 rpm) for 48 h; after filtration, it was washed three times with deionized water and dried to obtain boronized graphene oxide (B-pGO). L ); Take another 40mg GO L Graphene oxide with a sheet diameter of 500 nm to 1 μm was placed in 40 mL of DMF and sonicated for 1 h. Then, 20 mg each of EDC and NHS were added, and the mixture was stirred at room temperature (300 rpm) for 0.5 h. Subsequently, 120 mg of tris(hydroxymethyl)aminomethane was added, and the mixture was stirred at 60 °C (300 rpm) for 4 h. After filtration, the mixture was washed three times with deionized water and dried to obtain hydroxylated modified graphene oxide (OH-eGO). L Take 10mg of B-pGO. L Added to 10 mL of deionized water and sonicated for 1 hour, β-pGO was obtained. L (Concentration of 1 mg / mL); OH-eGO was prepared using the same method. L Dispersion (OH-eGO) L (Concentration of 2 mg / mL). OH-eGOL Adding B-pGO to the dispersion droplets L The pH of the dispersion was adjusted to 7 with phosphate buffer solution, and the mixture was stirred at room temperature (300 rpm) for 18 hours. After filtration, the mixture was washed three times with deionized water and dried to obtain hybrid graphene oxide (B-pGO). L @OH-eGO L (mass ratio 1:2)

[0053] Example 4

[0054] 40mg GO M Graphene oxide (with a sheet diameter of 200–500 nm) was placed in 20 mL of deionized water and sonicated for 1 h. 280 mg of 4-aminophenylboronic acid was added, and the pH was adjusted to 7.0 with phosphate buffer solution. The mixture was stirred at room temperature (300 rpm) for 24 h. After filtration, the mixture was washed three times with deionized water and dried to obtain B-pGO. M Take another 40mg of GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm) was placed in 20 mL of DMF and sonicated for 1 h. Then, 40 mg each of EDC and NHS were added, and the mixture was stirred at room temperature (300 rpm) for 0.5 h. Subsequently, 120 mg of tris(hydroxymethyl)aminomethane was added, and the mixture was stirred at 50 °C (300 rpm) for 12 h. After filtration, the mixture was washed three times with deionized water and dried to obtain OH-eGO. L Take 10mg of B-pGO M Added to 10 mL of deionized water and sonicated for 1 hour, β-pGO was obtained. M (Concentration of 1 mg / mL); OH-eGO was prepared using the same method. L Dispersion (OH-eGO) L (Concentration of 1 mg / mL). B-pGO M Adding OH-eGO to the dispersion droplets L The pH of the dispersion was adjusted to 7.3 with phosphate buffer solution, and the mixture was stirred at room temperature (300 rpm) for 18 hours. After filtration, the mixture was washed three times with deionized water and dried to obtain hybrid graphene oxide (B-pGO). M @OH-eGO L (mass ratio 1:1)

[0055] Example 5

[0056] Referring to the graphene oxide modification method in Example 4, 20 mg of B-pGO was used. M Replacement for 10mg B-pGO M With all other parameters and reaction conditions unchanged, hybrid graphene oxide (B-pGO) was prepared. M @OH-eGOL (mass ratio 2:1)

[0057] Example 6

[0058] Referring to the graphene oxide modification method in Example 4, 20 mg of OH-eGO was used. L Replacement for 10mg OH-eGO L With all other parameters and reaction conditions unchanged, hybrid graphene oxide (B-pGO) was prepared. M @OH-eGO L (1:2)).

[0059] Example 7

[0060] 40mg GO L Graphene oxide (with a sheet diameter of 500 nm to 1 μm) was placed in 20 mL of deionized water and sonicated for 1 h. 200 mg of 4-aminophenylboronic acid was added, and the pH was adjusted to 8.0 with phosphate buffer solution. The mixture was stirred at room temperature (300 rpm) for 30 h. After filtration, the mixture was washed three times with deionized water and dried to obtain B-pGO. L Take another 40mg of GO M (Graphene oxide with a sheet diameter of 200-500 nm) was placed in 40 mL of DMF and sonicated for 1 h. Then, 40 mg each of EDC and NHS were added, and the mixture was stirred at room temperature (300 rpm) for 1 h. Subsequently, 240 mg of tris(hydroxymethyl)aminomethane was added, and the mixture was stirred at 60 °C (300 rpm) for 6 h. After filtration, the mixture was washed three times each with deionized water and anhydrous ethanol, and then dried to obtain OH-eGO. M Take 10mg of B-pGO L Added to 10 mL of deionized water and sonicated for 1 hour, β-pGO was obtained. L (Concentration of 1 mg / mL); OH-eGO was prepared using the same method. M Dispersion (OH-eGO) M (Concentration is 1 mg / mL). OH-eGO M Adding B-pGO to the dispersion droplets L The pH of the dispersion was adjusted to 7.5 with phosphate buffer solution, and the mixture was stirred at room temperature (300 rpm) for 12 hours. After filtration, the mixture was washed three times each with deionized water and anhydrous ethanol, and then dried to obtain hybrid graphene oxide (B-pGO). L @OH-eGO M (mass ratio 1:1)

[0061] Example 8

[0062] Referring to the graphene oxide modification method in Example 7, 20 mg of B-pGO was used. LReplacement for 10mg B-pGO L With all other parameters and reaction conditions unchanged, hybrid graphene oxide (B-pGO) was prepared. L @OH-eGO M (mass ratio 2:1)

[0063] Example 9

[0064] Referring to the graphene oxide modification method in Example 7, 20 mg of OH-eGO was used. M Replacement for 10mg OH-eGO M With all other parameters and reaction conditions unchanged, hybrid graphene oxide (B-pGO) was prepared. L @OH-eGO M (mass ratio 1:2)

[0065] Example 10

[0066] 40mg GO M Graphene oxide (with a sheet diameter of 200–500 nm) was placed in 20 mL of deionized water and sonicated for 1 h. 280 mg of 4-aminophenylboronic acid was added, and the pH was adjusted to 7.0 with phosphate buffer solution. The mixture was stirred at room temperature (300 rpm) for 24 h. After filtration, the mixture was washed three times with deionized water and dried to obtain B-pGO. M Take another 40mg of GO M (Graphene oxide with a sheet diameter of 200-500 nm) was placed in 20 mL of DMF and sonicated for 1 h. Then, 80 mg each of EDC and NHS were added, and the mixture was stirred at room temperature (300 rpm) for 1 h. Subsequently, 240 mg of tris(hydroxymethyl)aminomethane was added, and the mixture was stirred at 60 °C (300 rpm) for 6 h. After filtration, the mixture was washed three times each with deionized water and anhydrous ethanol, and then dried to obtain OH-eGO. M Take 10mg of B-pGO M Added to 10 mL of deionized water and sonicated for 1 hour, β-pGO was obtained. M (Concentration of 1 mg / mL); OH-eGO was prepared using the same method. M Dispersion (OH-eGO) M (Concentration is 1 mg / mL). OH-eGO M Adding B-pGO to the dispersion droplets M The pH of the dispersion was adjusted to 7.5 with phosphate buffer solution, and the mixture was stirred at room temperature (300 rpm) for 12 hours. After filtration, the mixture was washed three times each with deionized water and anhydrous ethanol, and then dried to obtain hybrid graphene oxide (B-pGO). M @OH-eGO M (mass ratio 1:1)

[0067] Example 11

[0068] 40mg GO S (Graphene oxide with a sheet diameter of 50nm-200nm) was placed in 40mL of deionized water and sonicated for 1h until completely dispersed; 400mg of 4-aminophenylboronic acid was added, and the pH was adjusted to 7.0 with phosphate buffer solution. The mixture was stirred at room temperature (300rpm) for 36h; after filtration, it was washed three times each with deionized water and anhydrous ethanol and then dried to obtain B-pGO. S Take another 40mg of GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm) was placed in 40 mL of DMF and sonicated for 1 h until completely dispersed. EDC and NHS (40 mg each) were added and the mixture was stirred at room temperature (300 rpm) for 1 h. Then, 120 mg of tris(hydroxymethyl)aminomethane was added and the mixture was stirred at 55 °C (300 rpm) for 8 h. After filtration, washing, and drying, OH-eGO was obtained. L Take 10mg of B-pGO S Added to 10 mL of deionized water and sonicated for 1 hour, β-pGO was obtained. S (Concentration of 1 mg / mL); OH-eGO was prepared using the same method. L Dispersion (OH-eGO) L (Concentration is 1 mg / mL). OH-eGO L Adding B-pGO to the dispersion droplets S The pH of the dispersion was adjusted to 7.3 with phosphate buffer solution, stirred at room temperature (300 rpm) for 18 h, filtered, washed, and dried to obtain hybrid graphene oxide (B-pGO). S @OH-eGO L (mass ratio 1:1)

[0069] Example 12

[0070] Referring to the graphene oxide modification method in Example 11, 20 mg of B-GO was used. S Replacement for 10mg B-GO S With all other parameters and reaction conditions unchanged, hybrid graphene oxide (B-pGO) was prepared. S @OH-eGO L (mass ratio 2:1)

[0071] Example 13

[0072] Referring to the graphene oxide modification method in Example 11, 20 mg of OH-eGO was used. L Replacement for 10mg OH-eGO LWith all other parameters and reaction conditions unchanged, hybrid graphene oxide (B-pGO) was prepared. S @OH-eGO L (mass ratio 1:2)

[0073] Example 14

[0074] 40mg GO S (Graphene oxide with a sheet diameter of 50nm-200nm) was placed in 40mL of deionized water and sonicated for 1h until completely dispersed; 400mg of 4-aminophenylboronic acid was added, and the pH was adjusted to 7.0 with phosphate buffer solution. The mixture was stirred at room temperature (300rpm) for 36h; after filtration, it was washed three times each with deionized water and anhydrous ethanol and then dried to obtain B-pGO. S Take another 40mg of GO M (Graphene oxide with a sheet diameter of 200-500 nm) was placed in 40 mL of DMF and sonicated for 1 h until completely dispersed. Then, 40 mg each of EDC and NHS were added, and the mixture was stirred at room temperature (300 rpm) for 1 h. Subsequently, 240 mg of tris(hydroxymethyl)aminomethane was added, and the mixture was stirred at 55 °C (300 rpm) for 8 h. After filtration, washing, and drying, OH-eGO was obtained. M Take 10mg of B-pGO S Added to 10 mL of deionized water and sonicated for 1 hour, β-pGO was obtained. S (Concentration of 1 mg / mL); OH-eGO was prepared using the same method. M Dispersion (OH-eGO) M (Concentration is 1 mg / mL). OH-eGO M Adding B-pGO to the dispersion droplets S The pH of the dispersion was adjusted to 7.3 with phosphate buffer solution, stirred at room temperature (300 rpm) for 18 h, filtered, washed, and dried to obtain hybrid graphene oxide (B-pGO). S @OH-eGO M (mass ratio 1:1)

[0075] Example 15

[0076] 15 mg of B-pGO prepared in Example 1 was used. L @OH-eGO L (mass ratio 1:1) Ultrasonically dispersed in 15 mL of ethanol, centrifuged, and replaced with chloroform to obtain 40 mL of B-pGO. L @OH-eGO L A chloroform dispersion (mass ratio 1:1) with a concentration of 0.375 mg / mL was prepared. 2 g of PLA was dissolved in B-pGO. L @OH-eGOL The film-forming solution is obtained by sonication for 2 hours in a dispersion with a mass ratio of 1:1.

[0077] The resulting film-forming solution was poured into a mold and cured at room temperature for 24 hours. Then, it was transferred to a vacuum drying oven and dried at 50°C for 6 hours to obtain B-pGO. L @OH-eGO L (mass ratio 1:1) / PLA composite membrane. Among them, B-pGO... L @OH-eGO L The mass fraction of (1:1 mass ratio) in the composite membrane is 0.75 wt%.

[0078] Example 16

[0079] Referring to the film-forming process in Example 15, the B-pGO prepared in Example 2 was used. L @OH-eGO L (2:1 mass ratio) Replacement for B-pGO L @OH-eGO L (Mass ratio 1:1), with other process parameters unchanged, prepare B-pGO. L @OH-eGO L (mass ratio 2:1) / PLA composite membrane, B-pGO L @OH-eGO L The mass fraction of (2:1 mass ratio) in the composite membrane is 0.75 wt%.

[0080] Example 17

[0081] Referring to the film-forming process in Example 15, the B-pGO prepared in Example 3 was used. L @OH-eGO L (1:2 mass ratio) Replacement for B-pGO L @OH-eGO L (Mass ratio 1:1), with other process parameters unchanged, prepare B-pGO. L @OH-eGO L (mass ratio 1:2) / PLA composite membrane, B-pGO L @OH-eGO L The mass fraction of (mass ratio 1:2) in the composite membrane is 0.75 wt%.

[0082] Example 18

[0083] 15 mg of B-pGO prepared in Example 4 was used. M @OH-eGO L (mass ratio 1:1) Ultrasonically dispersed in 15 mL of ethanol, centrifuged, and replaced with chloroform to obtain 40 mL of B-pGO. M @OH-eGOL A chloroform dispersion (concentration 0.375 mg / mL) was prepared at a mass ratio of 1:1. 2 g of PLA was dissolved in the dispersion and sonicated for 2 hours to obtain the film-forming solution.

[0084] The resulting film-forming solution was poured into a mold and cured at room temperature for 48 hours. Then, it was transferred to a vacuum drying oven and dried at 30°C for 8 hours to obtain B-pGO. M @OH-eGO L (mass ratio 1:1) / PLA composite membrane. Among them, B-pGO... M @OH-eGO L The mass fraction of (1:1 mass ratio) in the composite membrane is 0.75 wt%.

[0085] Example 19

[0086] Referring to the film-forming process in Example 18, the B-pGO prepared in Example 5 was used. M @OH-eGO L (2:1 mass ratio) Replacement for B-pGO M @OH-eGO L (Mass ratio 1:1), with other process parameters unchanged, prepare B-pGO. M @OH-eGO L (mass ratio 2:1) / PLA composite membrane, B-pGO M @OH-eGO L The mass fraction of (2:1 mass ratio) in the composite membrane is 0.75 wt%.

[0087] Example 20

[0088] Referring to the film-forming process in Example 18, the B-pGO prepared in Example 6 was used. M @OH-eGO L (1:2 mass ratio) Replacement for B-pGO M @OH-eGO L (Mass ratio 1:1), with other process parameters unchanged, prepare B-pGO. M @OH-eGO L (mass ratio 1:2) / PLA composite membrane, B-pGO M @OH-eGO L The mass fraction of (mass ratio 1:2) in the composite membrane is 0.75 wt%.

[0089] Example 21

[0090] 15 mg of B-pGO prepared in Example 7 was used. L @OH-eGO M(mass ratio 1:1) Ultrasonically dispersed in 15 mL of ethanol, centrifuged, and replaced with chloroform to obtain 40 mL of B-pGO. L @OH-eGO M A chloroform dispersion (concentration 0.375 mg / mL) was prepared at a mass ratio of 1:1. 2 g of PLA was dissolved in the dispersion and sonicated for 2 hours.

[0091] The resulting film-forming solution was poured into a mold and cured at room temperature for 48 hours. Then, it was transferred to a vacuum drying oven and dried at 55°C for 6 hours to obtain B-pGO. L @OH-eGO M (mass ratio 1:1) / PLA composite membrane. Among them, B-pGO... L @OH-eGO M The mass fraction of (1:1 mass ratio) in the composite membrane is 0.75 wt%.

[0092] Example 22

[0093] Referring to the film-forming process in Example 21, the B-pGO prepared in Example 8 was used. L @OH-eGO M (2:1 mass ratio) Replacement for B-pGO L @OH-eGO M (Mass ratio 1:1), with other process parameters unchanged, prepare B-pGO. L @OH-eGO M (mass ratio 2:1) / PLA composite membrane, B-pGO L @OH-eGO M The mass fraction of (2:1 mass ratio) in the composite membrane is 0.75 wt%.

[0094] Example 23

[0095] Referring to the film-forming process in Example 21, the B-pGO prepared in Example 9 was used. L @OH-eGO M (1:2 mass ratio) Replacement for B-pGO L @OH-eGO M (Mass ratio 1:1), with other process parameters unchanged, prepare B-pGO. L @OH-eGO M (mass ratio 1:2) / PLA composite membrane, B-pGO L @OH-eGO M The mass fraction of (mass ratio 1:2) in the composite membrane is 0.75 wt%.

[0096] Example 24

[0097] Referring to the film-forming process in Example 21, the B-pGO prepared in Example 10 was used. M @OH-eGO M (1:1 mass ratio) Replacement for B-pGO L @OH-eGO M (Mass ratio 1:1), with other process parameters unchanged, prepare B-pGO. M @OH-eGO M (mass ratio 1:1) / PLA composite membrane, B-pGO M @OH-eGO M The mass fraction of (1:1 mass ratio) in the composite membrane is 0.75 wt%.

[0098] Example 25

[0099] 15 mg of B-pGO prepared in Example 11 was used. S @OH-eGO L (mass ratio 1:1) Ultrasonically dispersed in 15 mL of ethanol, centrifuged, and replaced with chloroform to obtain 40 mL of B-pGO. S @OH-eGO L A chloroform dispersion (concentration 0.375 mg / mL) was prepared at a mass ratio of 1:1. 2 g of PLA was dissolved in the dispersion and sonicated for 2 hours.

[0100] The resulting film-forming solution was poured into a mold and cured at room temperature for 24 hours. Then, it was transferred to a vacuum drying oven and dried at 50°C for 7 hours to obtain B-pGO. S @OH-eGO L (mass ratio 1:1) / PLA composite membrane. Among them, B-pGO... S @OH-eGO L The mass fraction of (1:1 mass ratio) in the composite membrane is 0.75 wt%.

[0101] Example 26

[0102] Referring to the film-forming process in Example 25, the B-pGO prepared in Example 12 was used. S @OH-eGO L (2:1 mass ratio) Replacement for B-pGO S @OH-eGO L (Mass ratio 1:1), with other process parameters unchanged, prepare B-pGO. S @OH-eGO L (mass ratio 2:1) / PLA composite membrane, B-pGO S @OH-eGO L The mass fraction of (2:1 mass ratio) in the composite membrane is 0.75 wt%.

[0103] Example 27

[0104] Referring to the film-forming process in Example 25, the B-pGO prepared in Example 13 was used. S @OH-eGO L (1:2 mass ratio) Replacement for B-eGO S @OH-pGO L (Mass ratio 1:1), with other process parameters unchanged, prepare B-pGO. S @OH-eGO L (mass ratio 1:2) / PLA composite membrane, B-pGO S @OH-eGO L The mass fraction of (mass ratio 1:2) in the composite membrane is 0.75 wt%.

[0105] Example 28

[0106] Referring to the film-forming process in Example 25, the B-pGO prepared in Example 14 was used. S @OH-eGO M (1:1 mass ratio) Replacement for B-pGO S @OH-eGO L (Mass ratio 1:1), with other process parameters unchanged, prepare B-pGO. S @OH-eGO M (mass ratio 1:1) / PLA composite membrane, B-pGO S @OH-eGO M The mass fraction of (1:1 mass ratio) in the composite membrane is 0.75 wt%.

[0107] Example 29

[0108] 8 mg of B-pGO prepared in Example 4 M @OH-eGO L (mass ratio 1:1) Ultrasonically dispersed in 15 mL of ethanol, centrifuged, and replaced with chloroform to obtain 40 mL of B-pGO. M @OH-eGO L A chloroform dispersion (concentration 0.2 mg / mL) with a mass ratio of 1:1 was prepared. 3.2 g of PLA was dissolved in the dispersion and sonicated for 2 h to obtain the film-forming solution.

[0109] The resulting film-forming solution was poured into a mold and cured at room temperature for 36 hours. Then, it was transferred to a vacuum drying oven and dried at 50°C for 6 hours to obtain B-pGO. M @OH-eGO L (mass ratio 1:1) / PLA composite membrane. Among them, B-pGO... M @OH-eGO LThe mass fraction of (1:1 mass ratio) in the composite membrane is 0.25 wt%.

[0110] Example 30

[0111] 10 mg of B-pGO prepared in Example 4 was used. M @OH-eGO L (mass ratio 1:1) Sonicated in 15 mL of ethanol, centrifuged, and replaced with chloroform to obtain 40 mL of B-pGO. M @OH-eGO L A chloroform dispersion (concentration 0.25 mg / mL) with a mass ratio of 1:1 was prepared. 2 g of PLA was dissolved in the dispersion and sonicated for 2 h to obtain the film-forming solution.

[0112] The resulting film-forming solution was poured into a mold and cured at room temperature for 24 hours. Then, it was transferred to a vacuum drying oven and dried at 50°C for 6 hours to obtain B-pGO. M @OH-eGO L (mass ratio 1:1) / PLA composite membrane. Among them, B-pGO... M @OH-eGO L The mass fraction of (1:1 mass ratio) in the composite membrane is 0.5 wt%.

[0113] Example 31

[0114] 20 mg of B-pGO prepared in Example 4 M @OH-eGO L (mass ratio 1:1) Ultrasonically dispersed in 20 mL of ethanol, centrifuged, and replaced with chloroform to obtain 40 mL of B-pGO. M @OH-eGO L A chloroform dispersion (concentration 0.5 mg / mL) with a mass ratio of 1:1 was prepared. 2 g of PLA was dissolved in the dispersion and sonicated for 2 h to obtain the film-forming solution.

[0115] The resulting film-forming solution was poured into a mold and cured at room temperature for 48 hours. Then, it was transferred to a vacuum drying oven and dried at 50°C for 6 hours to obtain B-pGO. M @OH-eGO L (mass ratio 1:1) / PLA composite membrane. Among them, B-pGO... M @OH-eGO L The mass fraction of (mass ratio 1:1) in the composite membrane is 1 wt%.

[0116] To further illustrate the effect of the oxygen barrier membrane prepared in this invention, composite membranes were prepared using graphene oxide, dodecylamine-modified graphene oxide (DDA-GO), and polyethylene glycol-modified graphene oxide (PEG-GO) as fillers as comparative examples.

[0117] Comparative Example 1

[0118] 15mg GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm) was ultrasonically dispersed in 15 mL of ethanol, centrifuged, and replaced with chloroform to obtain 40 mL of GO. L Chloroform dispersion (concentration 0.375 mg / mL) was prepared by dissolving 2 g PLA in the dispersion and sonicating for 2 h to obtain the film-forming solution.

[0119] The resulting film-forming solution was poured into a mold and cured at room temperature for 24 hours. Then, it was transferred to a vacuum drying oven and dried at 50°C for 6 hours to obtain GO. L / PLA composite membrane. Among them, GO L The mass fraction in the composite membrane is 0.75 wt%.

[0120] Comparative Example 2

[0121] Referring to the film-forming process in Comparative Example 1, GO was used. M (Graphene oxide with a sheet diameter of 200-500 nm) as a substitute for GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm), with other process parameters remaining unchanged, GO was prepared. M / PLA composite membrane, in which GO M The mass fraction in the composite membrane is 0.75 wt%.

[0122] Comparative Example 3

[0123] Referring to the film-forming process in Comparative Example 1, GO was used. S (Graphene oxide with a sheet diameter of 50nm-200nm) as a substitute for GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm), with other process parameters remaining unchanged, GO was prepared. S / PLA composite membrane, in which GO S The mass fraction in the composite membrane is 0.75 wt%.

[0124] Comparative Example 4

[0125] 40mg GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm) was placed in 40 mL of deionized water and sonicated for 1 h. 1.09 mmol of dodecylamine (DDA) was added, and the pH was adjusted to 7.0 with phosphate buffer solution. The mixture was stirred at room temperature (300 rpm) for 24 h. After filtration, the mixture was washed three times with deionized water and dried to obtain DDA-GO. L . Take 15mg DDA-GO L The solution was placed in 15 mL of ethanol, centrifuged, and replaced with chloroform to obtain 40 mL of DDA-GO. LChloroform dispersion (concentration 0.375 mg / mL) was prepared by dissolving 2 g PLA in the dispersion and sonicating for 2 h to obtain the film-forming solution.

[0126] The resulting film-forming solution was poured into a mold and cured at room temperature for 24 hours. Then, it was transferred to a vacuum drying oven and dried at 50°C for 6 hours to obtain DDA-GO. L / PLA composite membrane. Among them, DDA-GO L The mass fraction in the composite membrane is 0.75 wt%.

[0127] Comparative Example 5

[0128] Referring to the modification method of graphene oxide in Comparative Example 4, GO was used. M (Graphene oxide with a sheet diameter of 200-500 nm) as a substitute for GO L DDA-GO was prepared by using graphene oxide sheets with a diameter of 500 nm to 1 μm, while keeping all other parameters and reaction conditions unchanged. M Referring to the film-forming process in Comparative Example 4, DDA-GO was used. M Alternative to DDA-GO L , Preparation of DDA-GO M / PLA composite membrane, in which DDA-GO M The mass fraction in the composite membrane is 0.75 wt%.

[0129] Comparative Example 6

[0130] Referring to the modification method of graphene oxide in Comparative Example 4, GO was used. S (Graphene oxide with a sheet diameter of 50nm-200nm) as a substitute for GO L DDA-GO was prepared by using graphene oxide sheets with a diameter of 500 nm to 1 μm, while keeping all other parameters and reaction conditions unchanged. S Referring to the film-forming process in Comparative Example 4, DDA-GO was used. S Alternative to DDA-GO L , Preparation of DDA-GO S / PLA composite membrane, in which DDA-GO M The mass fraction in the composite membrane is 0.75 wt%.

[0131] Comparative Example 7

[0132] 40mg GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm) was placed in 40 mL of deionized water and sonicated for 1 h. 1.34 mmol of α-hydroxy-ω-amino polyethylene glycol was added, and the pH was adjusted to 7.0 with phosphate buffer solution. The mixture was stirred at room temperature (300 rpm) for 24 h. After filtration, the mixture was washed three times with deionized water and dried to obtain PEG-GO.L Take 15mg of PEG-GO L The PEG-GO was placed in 15 mL of ethanol, centrifuged, and replaced with chloroform to obtain 40 mL of PEG-GO. L Chloroform dispersion (concentration 0.375 mg / mL) was prepared by dissolving 2 g PLA in the dispersion and sonicating for 2 h to obtain the film-forming solution.

[0133] The resulting film-forming solution was poured into a mold and cured at room temperature for 24 hours. Then, it was transferred to a vacuum drying oven and dried at 50°C for 6 hours to obtain PEG-GO. L / PLA composite membrane. Including PEG-GO L The mass fraction in the composite membrane is 0.75 wt%.

[0134] Comparative Example 8

[0135] Referring to the modification method of graphene oxide in Comparative Example 7, GO was used. M (Graphene oxide with a sheet diameter of 200-500 nm) as a substitute for GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm), with all other parameters and reaction conditions unchanged, PEG-GO was prepared. M Referring to the film-forming process in Comparative Example 4, PEG-GO was used. M Alternative to PEG-GO L Preparation of PEG-GO M / PLA composite membrane, in which PEG-GO M The mass fraction in the composite membrane is 0.75 wt%.

[0136] Comparative Example 9

[0137] Referring to the modification method of graphene oxide in Comparative Example 7, GO was used. S (Graphene oxide with a sheet diameter of 50nm-200nm) as a substitute for GO L (Graphene oxide with a sheet diameter of 500 nm to 1 μm), with all other parameters and reaction conditions unchanged, PEG-GO was prepared. S Referring to the film-forming process in Comparative Example 4, PEG-GO was used. S Alternative to PEG-GO L Preparation of PEG-GO S / PLA composite membrane, in which PEG-GO S The mass fraction in the composite membrane is 0.75 wt%.

[0138] Fourier transform infrared spectroscopy (FT-IR) was used to analyze graphene oxide modified with 4-aminophenylboronic acid, graphene oxide modified with tris(hydroxymethyl)aminomethane, and the hybrid graphene oxide (B-pGO) of Example 1. L @OH-eGO LCharacterization was performed on graphene oxide (mass ratio 1:1) and the results are as follows: Figure 4 As shown.

[0139] The oxygen barrier properties of the composite membrane were characterized by the relative oxygen permeability coefficient (i.e., the ratio of the composite membrane's oxidation permeability coefficient to the pure PLA membrane's oxygen permeability coefficient). A smaller composite membrane permeability coefficient indicates better barrier performance. The oxygen permeability coefficient was tested according to the method for determining the gas permeability of thin films and sheets described in GB / T 1038-2000. The controlled test conditions were: temperature 22℃, humidity 35%, and oxygen cylinder pressure 0.4 MPa. The permeability coefficient of the prepared biodegradable composite membrane material was measured. The test results are listed in the table below.

[0140] Table 1 Relative oxygen permeability coefficient of composite membrane

[0141]

[0142] The test results show that the hybridized graphene oxide significantly improves the oxygen barrier properties of the composite material. (B-pGO) M @OH-eGO L The oxygen barrier performance of the (1:1) / PLA composite membrane is better than that of the unmodified GO. L / PLA improved by approximately 78%, compared to DDA-GO L The PLA composite membrane improved by approximately 53% compared to PEG-GO. L The PLA composite membrane improved oxygen barrier properties by approximately 58%, and the composite membrane prepared by this invention exhibits excellent oxygen barrier performance.

[0143] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A degradable high oxygen barrier composite film, characterized in that, It is composed of PLA and hybrid graphene oxide; The hybrid graphene oxide is obtained by a click chemical reaction of boronized graphene oxide and hydroxylated graphene oxide in a mass ratio of 1:2 to 2:

1. The boronized graphene oxide is obtained by reacting graphene oxide with 4-aminophenylboronic acid; The hydroxylated graphene oxide is obtained by reacting graphene oxide with a carboxyl activator, followed by a reaction with tris(hydroxymethyl)aminomethane. The hybrid graphene oxide accounts for 0.25 to 1 wt% of the composite film.

2. The degradable high oxygen barrier composite film according to claim 1, characterized in that, The boronized graphene oxide is obtained by reacting graphene oxide with 4-aminophenylboronic acid in a mass ratio of 1:4 to 10. And / or, the hydroxylated graphene oxide is obtained by reacting graphene oxide, N-hydroxysuccinimide and 1-ethyl-(3-dimethylaminopropyl) in a mass ratio of 1:0.5 to 2:0.5 to 2, and then reacting it with tris(hydroxymethylaminomethane) in a mass ratio of 1:2 to 6.

3. The degradable high oxygen barrier composite film according to claim 1 or 2, characterized in that, The graphene oxide is a single-layer sheet-like graphene oxide with a sheet diameter of 50 nm to 5 μm.

4. The degradable high oxygen barrier composite film according to claim 1 or 2, characterized in that, The click chemical reaction was carried out at room temperature, with a pH of 7–8 and a reaction time of 8–18 h. And / or, the reaction temperature of the graphene oxide with 4-aminophenylboronic acid is room temperature, the pH of the reaction system is 7-9, and the reaction time is 24-48 h; And / or, the reaction temperature of the graphene oxide with the carboxyl activator is room temperature and the time is 0.5 to 1 h; the reaction temperature with tris(hydroxymethyl)aminomethane is 50 to 70 °C and the time is 4 to 12 h.

5. The method of claim 1 to 4 for the preparation of a degradable high oxygen barrier composite film, characterized in that, Includes the following steps: (1) Graphene oxide was dispersed in water, 4-aminophenylboronic acid was added and the pH was adjusted. After the reaction was carried out at room temperature, the boronized graphene oxide was obtained by filtration, washing with water and drying. (2) Graphene oxide is dispersed in an organic solvent, a carboxyl activator is added and reacted at room temperature, then tris(hydroxymethyl)aminomethane is added and heated to react. After filtration, washing with water and drying, hydroxylated graphene oxide is obtained. (3) Boronized graphene oxide and hydroxylated graphene oxide are mixed and dispersed in water, and the pH is adjusted before reaction. After filtration, washing with water and drying, hybrid graphene oxide is obtained. (4) Disperse hybrid graphene oxide in ethanol, and obtain chloroform dispersion by chloroform replacement. Then add PLA and mix evenly to obtain film-forming liquid. Demold and solidify to obtain degradable oxygen barrier film.

6. The method for preparing a biodegradable high oxygen barrier composite membrane according to claim 5, characterized in that, The graphene oxide described in steps (1) and (2) is a single-layer sheet graphene oxide with a sheet diameter of 50 nm to 5 μm; And / or, the mass ratio of 4-aminophenylboronic acid and graphene oxide in step (1) is 4 to 10:1; And / or, the carboxyl activator in step (2) is N-hydroxysuccinimide and 1-ethyl-(3-dimethylaminopropyl); the mass ratio of N-hydroxysuccinimide, 1-ethyl-(3-dimethylaminopropyl) to graphene oxide is 0.5-2:0.5-2:1; And / or, the mass ratio of tris(hydroxymethyl)aminomethane to graphene oxide in step (2) is 2 to 6:1; And / or, the mass ratio of the boric acidified graphene oxide and the hydroxylated graphene oxide in step (3) is 1:2-2:

1. And / or, the mass ratio of the hybrid graphene oxide and the PLA in step (4) is 2-5:500-800.

7. The method for preparing a biodegradable high oxygen barrier composite membrane according to claim 5 or 6, characterized in that, The pH in step (1) is adjusted to a range of 7-9. And / or, the reaction time in step (1) is 24-48 h at room temperature. And / or, the reaction time in step (2) is 0.5-1 h at room temperature. And / or, the heating reaction temperature in step (2) is 50-70 ℃; and the reaction time is 4-12 h.

8. The method for preparing a biodegradable high oxygen barrier composite membrane according to claim 5 or 6, characterized in that, The pH in step (3) is adjusted to a range of 7-8. And / or, the reaction temperature in step (3) is room temperature; and the reaction time is 8-18 h. And / or, the film-forming solution in step (4) is first surface-cured at room temperature for 24-48 h, and then dried at 30-55 ℃ for 6-8 h.

9. The method for preparing a biodegradable high oxygen barrier composite membrane according to claim 5 or 6, characterized in that, The concentration of the graphene oxide dispersion in water in step (1) is 1-2 mg / mL. And / or, the concentration of the graphene oxide dispersion in the organic solvent in step (2) is 1-2 mg / mL. And / or, the concentration of the boric acidified graphene oxide and the hydroxylated graphene oxide mixed dispersion in water in step (3) is 1-2 mg / mL. And / or, the mass concentration of the hybrid graphene oxide in chloroform in step (4) is 0.2-0.5 mg / mL. And / or, the organic solvent in step (2) is dimethylformamide.

10. The use of the degradable high-oxygen-barrier composite film according to any one of claims 1-4 in the packaging field.

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