Method for enhancing hydrophobicity of BC membrane straw by using fluorocarbon resin membrane

Abstract

The invention belongs to the technical field of surface modification of environment-friendly materials, and particularly relates to a method for enhancing hydrophobicity of a BC membrane straw by using a fluorocarbon resin membrane. Comprising the following steps: preparing a BC membrane suction tube; pre-treating a BC membrane suction tube; preparing a fluorocarbon resin solution; coating a fluorocarbon resin solution; and drying and curing. The method is green and environment-friendly, the process is simple, convenient and controllable, the preparation process is easy to operate, compared with other complex modification technologies, the cost is greatly reduced, and the treated BC membrane straw has biodegradability and excellent hydrophobic performance, has unique advantages in the degradable straw market and meets the requirements of consumers for environment-friendly and high-performance straws.

Description

Technical Field

[0001] The invention belongs to the technical field of surface modification of environmentally friendly materials, and particularly relates to a method for enhancing the hydrophobicity of a BC film straw by using a fluorocarbon resin film. Background Art

[0002] In recent years, with the advancement of the "plastic restriction order", degradable straws made from biomass such as corn straw have received widespread attention. Bacterial cellulose (hereinafter referred to as BC) membrane straws are made from bacterial cellulose prepared by fermenting corn straw. They have good biodegradability and safety, but have obvious defects. Since the BC membrane itself is highly hydrophilic, when it comes into contact with liquids such as beverages, it will quickly absorb water and soften, resulting in a decrease in the strength of the straw, deformation, or even breakage, which seriously affects the user experience and limits its promotion and application in the market. At present, there are few methods for improving the hydrophobicity of BC membrane straws, and some methods have problems such as complex processes, high costs, and the use of non-environmentally friendly materials, making it difficult to meet large-scale production and environmental protection needs. Therefore, the development of a simple, efficient, green and environmentally friendly method that can significantly enhance the hydrophobicity of BC membrane straws has important practical significance and market value for promoting the development of the biomass-based straw industry and solving the pain points of existing technologies. Summary of the Invention

[0003] In response to the above problems, the present application provides a method for enhancing the hydrophobicity of BC membrane straws using a fluorocarbon resin membrane.

[0004] To achieve the above objectives, the present application provides a method for enhancing the hydrophobicity of a BC membrane straw using a fluorocarbon resin membrane, comprising the following steps:

[0005] S1. Preparation of BC membrane straws: corn stalks are crushed, an alkaline solution is added, the mixture is steamed, and the mixture is centrifuged. The precipitate is stirred with water, the pH is adjusted to acidic, cellulase is added, and the mixture is centrifuged. The supernatant is inoculated with Acetobacter xylinum for fermentation. The bacterial cellulose is then collected, washed, and dried to produce a BC membrane, which is then processed into straws to obtain BC membrane straws.

[0006] S2. Pretreatment of BC membrane straws: soaking the prepared BC membrane straws in an alkaline solution, taking them out and washing them, then soaking them in a silane coupling agent solution, taking them out and drying them, to obtain pretreated BC membrane straws;

[0007] S3, preparation of fluorocarbon resin solution: dissolving fluorocarbon resin in ethanol-water mixed solvent and stirring to obtain fluorocarbon resin solution;

[0008] S4, coating with fluorocarbon resin solution: immerse the pretreated BC membrane straw in the fluorocarbon resin solution for 2-3 minutes, then rotate the straw to form a fluorocarbon resin liquid film to obtain a coated BC membrane straw;

[0009] S5. Drying and curing: The coated BC film straw is placed in a vacuum drying oven for drying, and then heated and cured under vacuum conditions to obtain a fluorocarbon resin film reinforced BC film straw.

[0010] Furthermore, the alkaline solution is a sodium hydroxide solution or a potassium hydroxide solution.

[0011] Furthermore, the silane coupling agent is one of γ-aminopropyltriethoxysilane, vinyltrimethoxysilane, and γ-methacryloyloxytrimethoxysilane.

[0012] Furthermore, the fluorocarbon resin is one of polyvinylidene fluoride, ethylene-tetrafluoroethylene copolymer, and polytetrafluoroethylene.

[0013] Furthermore, the mass ratio of the fluorocarbon resin to the ethanol-water mixed solvent is 1:10-15.

[0014] Furthermore, the rotation in step S4 has a rotation speed of 80-120 rpm.

[0015] Furthermore, the temperature of the vacuum drying oven is 50-60° C. and the drying time is 30-45 minutes.

[0016] Furthermore, the temperature is raised to 120-150° C. in step S5 .

[0017] Furthermore, the vacuum degree of step S5 is -0.08 to -0.06 MPa.

[0018] In summary, this application has the following beneficial effects:

[0019] The method used in this application significantly improves the hydrophobicity of BC film straws. The BC film straws treated by this method have greatly improved hydrophobicity compared to untreated straws, and can effectively resist the infiltration of liquids such as beverages. After soaking in beverages for 4 hours, they can still maintain good structural strength and shape, greatly improving the user experience and comparable to the performance of traditional plastic straws.

[0020] The method used in this application is environmentally friendly. BC membrane straws are prepared from corn stalks, achieving high-value utilization of biomass resources. The fluorocarbon resin used is a food-grade material, and the solvent is an ethanol-water mixture system, which is non-toxic, harmless, and volatile. The entire process does not emit harmful pollutants, meeting environmental protection requirements. The process of this application is simple and controllable, and the preparation process is simple to operate. Compared with other complex modification technologies, the cost is significantly reduced. The treated BC membrane straws are both biodegradable and have excellent hydrophobic properties. They have unique advantages in the degradable straw market and meet consumer demand for environmentally friendly and high-performance straws. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 This is a diagram of a BC film straw treated with the present invention after being immersed in cola for 4 hours;

[0023] Figure 2 This is a picture of an untreated BC membrane straw after being soaked in cola for 4 hours. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] The raw materials used in the examples of the present invention are as follows, and all reagents used are of analytical grade.

[0026] Among them, polyvinylidene fluoride was selected from Hubei Fangde New Materials Co., Ltd., with the number: C15115; ethylene-tetrafluoroethylene copolymer was selected from Suzhou Senfida Chemical Co., Ltd., with the number: sfd106; Acetobacter xylinum was selected from Henan Wanjia Standard Material Research and Development Center, with the number: BWCC66501; and cellulase was selected from Guangdong Hongjiang Chemical Reagent Co., Ltd., with the number: PB40007.

[0027] Example 1

[0028] A method for enhancing the hydrophobicity of a BC film straw using a fluorocarbon resin film comprises the following steps:

[0029] S1. Preparation of BC membrane straws: corn straw was crushed and sieved (pore size 6 mm), the undersize powder was collected, and a 2% NaOH solution was added at a mass ratio of 1:10. The mixture was steamed at 100°C for 30 minutes, and then centrifuged (speed 1200 rpm, time 3 minutes). The precipitate was mixed with 50°C water at a mass ratio of 1:2 and stirred. The pH was adjusted to 5 with a mass concentration of 5% sulfuric acid solution. A cellulase solution with an activity of 25 U / ml was added at a volume ratio of 100:1. The mixture was reacted at 50°C for 3 days, and then centrifuged (speed 2000 rpm, time 10 minutes). The supernatant was inoculated with 10% inoculum of Acetobacter xylinum for fermentation and culture. The mixture was fermented at 30°C for 7 days. The bacterial cellulose was collected, washed with deionized water 3 times, and freeze-dried at -50°C for 48 hours to obtain a BC membrane. The BC membrane was then processed into straws by hot pressing (temperature 120°C, pressure 5 MPa, time 10 minutes) to obtain BC membrane straws.

[0030] S2. Pretreatment of BC membrane straws: The prepared BC membrane straws were placed in a 1% sodium hydroxide solution at 40°C for 10 minutes, removed and rinsed with deionized water five times, then placed in a 0.5% γ-aminopropyltriethoxysilane solution at 30°C for 5 minutes, removed and dried at room temperature to obtain pretreated BC membrane straws.

[0031] S3. Preparation of fluorocarbon resin solution: dissolving ethylene-tetrafluoroethylene copolymer in an ethanol-water mixed solvent (the volume ratio of ethanol to water is 7:3), with the mass ratio of ethylene-tetrafluoroethylene copolymer to the ethanol-water mixed solvent being 1:10, and stirring at 25° C. and 400 rpm for 1.5 hours to obtain a fluorocarbon resin solution;

[0032] S4, coating with fluorocarbon resin solution: vertically immerse the pretreated BC membrane straw in the fluorocarbon resin solution for 2 minutes, and then rotate the straw at 80 rpm for 1 minute to form a coated BC membrane straw;

[0033] S5. Drying and curing: Place the coated BC film straw in a vacuum drying oven, first dry it at 50°C for 30 minutes, then heat it to 120°C, and cure it at a vacuum degree of -0.08 MPa for 1 hour to obtain a fluorocarbon resin film reinforced BC film straw.

[0034] Example 2

[0035] A method for enhancing the hydrophobicity of a BC film straw using a fluorocarbon resin film comprises the following steps:

[0036] S1. Preparation of BC membrane straws: corn straw was crushed and sieved (pore size 6 mm), the undersize powder was collected, and a 2% NaOH solution was added at a mass ratio of 1:10. The mixture was steamed at 100°C for 30 minutes, and then centrifuged (speed 1200 rpm, time 3 minutes). The precipitate was mixed with 50°C water at a mass ratio of 1:2 and stirred. The pH was adjusted to 5 with a mass concentration of 5% sulfuric acid solution. A cellulase solution with an activity of 25 U / ml was added at a volume ratio of 100:1. The mixture was reacted at 50°C for 3 days, and then centrifuged (speed 2000 rpm, time 10 minutes). The supernatant was inoculated with 10% inoculum of Acetobacter xylinum for fermentation and culture. The mixture was fermented at 30°C for 7 days. The bacterial cellulose was collected, washed with deionized water 3 times, and freeze-dried at -50°C for 48 hours to obtain a BC membrane. The BC membrane was then processed into straws by hot pressing (temperature 120°C, pressure 5 MPa, time 10 minutes) to obtain BC membrane straws.

[0037] S2. BC membrane straw pretreatment: The prepared BC membrane straw was placed in a 2% sodium hydroxide solution at 45°C for 12 minutes, removed and rinsed with deionized water five times, then placed in a 1% vinyltrimethoxysilane solution at 35°C for 8 minutes, removed and dried at room temperature to obtain a pretreated BC membrane straw;

[0038] S3. Preparation of fluorocarbon resin solution: polyvinylidene fluoride was dissolved in an ethanol-water mixed solvent (the volume ratio of ethanol to water was 7:3), with the mass ratio of polyvinylidene fluoride to the ethanol-water mixed solvent being 1:13. The mixture was stirred at 30° C. and 500 rpm for 2 hours to obtain a fluorocarbon resin solution.

[0039] S4, coating with fluorocarbon resin solution: vertically immerse the pretreated BC membrane straw in the fluorocarbon resin solution for 3 minutes, and then rotate the straw at 100 rpm for 1.5 minutes to form a coated BC membrane straw;

[0040] S5. Drying and curing: Place the coated BC film straw in a vacuum drying oven, first dry it at 55°C for 40 minutes, then heat it to 135°C, and cure it at a vacuum degree of -0.07 MPa for 1.5 hours to obtain a fluorocarbon resin film reinforced BC film straw.

[0041] Example 3

[0042] A method for enhancing the hydrophobicity of a BC film straw using a fluorocarbon resin film comprises the following steps:

[0043] S1. Preparation of BC membrane straws: corn straw was crushed and sieved (pore size 6 mm), the undersize powder was collected, and a 2% NaOH solution was added at a mass ratio of 1:10. The mixture was steamed at 100°C for 30 minutes, and then centrifuged (speed 1200 rpm, time 3 minutes). The precipitate was mixed with 50°C water at a mass ratio of 1:2 and stirred. The pH was adjusted to 5 with a mass concentration of 5% sulfuric acid solution. A cellulase solution with an activity of 25 U / ml was added at a volume ratio of 100:1. The mixture was reacted at 50°C for 3 days, and then centrifuged (speed 2000 rpm, time 10 minutes). The supernatant was inoculated with 10% inoculum of Acetobacter xylinum for fermentation and culture. The mixture was fermented at 30°C for 7 days. The bacterial cellulose was collected, washed with deionized water 3 times, and freeze-dried at -50°C for 48 hours to obtain a BC membrane. The BC membrane was then processed into straws by hot pressing (temperature 120°C, pressure 5 MPa, time 10 minutes) to obtain BC membrane straws.

[0044] S2. Pretreatment of BC membrane straws: The prepared BC membrane straws were placed in a 3% sodium hydroxide solution at 50°C for 15 minutes, removed and rinsed with deionized water five times, then placed in a 1.5% γ-aminopropyltriethoxysilane solution at 40°C for 10 minutes, removed and dried at room temperature to obtain pretreated BC membrane straws.

[0045] S3. Preparation of fluorocarbon resin solution: Dissolve polyvinylidene fluoride in an ethanol-water mixed solvent (the volume ratio of ethanol to water is 7:3), with the mass ratio of polyvinylidene fluoride to the mixed solvent being 1:15, and stir at 35° C. and 600 rpm for 2.5 hours to obtain a fluorocarbon resin solution;

[0046] S4, coating with fluorocarbon resin solution: vertically immerse the pretreated BC membrane straw in the fluorocarbon resin solution for 3 minutes, and then rotate the straw at 120 rpm for 2 minutes to form a coated BC membrane straw;

[0047] S5. Drying and curing: Place the coated BC film straw in a vacuum drying oven, first dry it at 60°C for 45 minutes, then heat it to 150°C, and cure it at a vacuum degree of -0.06 MPa for 2 hours to obtain a fluorocarbon resin film reinforced BC film straw.

[0048] Comparative Example 1

[0049] A method for enhancing the hydrophobicity of a BC film straw using a fluorocarbon resin film comprises the following steps:

[0050] S1. Preparation of BC membrane straws: corn straw was crushed and sieved (pore size 6 mm), the undersize powder was collected, and a 2% NaOH solution was added at a mass ratio of 1:10. The mixture was steamed at 100°C for 30 minutes, and then centrifuged (speed 1200 rpm, time 3 minutes). The precipitate was mixed with 50°C water at a mass ratio of 1:2 and stirred. The pH was adjusted to 5 with a mass concentration of 5% sulfuric acid solution. A cellulase solution with an activity of 25 U / ml was added at a volume ratio of 100:1. The mixture was reacted at 50°C for 3 days, and then centrifuged (speed 2000 rpm, time 10 minutes). The supernatant was inoculated with 10% inoculum of Acetobacter xylinum for fermentation and culture. The mixture was fermented at 30°C for 7 days. The bacterial cellulose was collected, washed with deionized water 3 times, and freeze-dried at -50°C for 48 hours to obtain a BC membrane. The BC membrane was then processed into straws by hot pressing (temperature 120°C, pressure 5 MPa, time 10 minutes) to obtain BC membrane straws.

[0051] S2. BC membrane straw pretreatment: The prepared BC membrane straw was placed in a 2% sodium hydroxide solution at 45°C for 12 minutes, removed and rinsed with deionized water five times, then placed in a 1% vinyltrimethoxysilane solution at 35°C for 8 minutes, removed and dried at room temperature to obtain a pretreated BC membrane straw;

[0052] S3. Preparation of fluorocarbon resin solution: Dissolve polyvinylidene fluoride in an ethanol-water mixed solvent (the volume ratio of ethanol to water is 7:3), with the mass ratio of polyvinylidene fluoride to the ethanol-water mixed solvent being 1:8, and stir at 30° C. and 500 rpm for 2 hours to obtain a fluorocarbon resin solution;

[0053] S4, coating with fluorocarbon resin solution: vertically immerse the pretreated BC membrane straw in the fluorocarbon resin solution for 3 minutes, and then rotate the straw at 100 rpm for 1.5 minutes to form a coated BC membrane straw;

[0054] S5. Drying and curing: Place the coated BC film straw in a vacuum drying oven, first dry it at 55°C for 40 minutes, then heat it to 135°C, and cure it at a vacuum degree of -0.07 MPa for 1.5 hours to obtain a fluorocarbon resin film reinforced BC film straw.

[0055] Comparative Example 2

[0056] A method for enhancing the hydrophobicity of a BC film straw using a fluorocarbon resin film comprises the following steps:

[0057] S1. Preparation of BC membrane straws: corn straw was crushed and sieved (pore size 6 mm), the undersize powder was collected, and a 2% NaOH solution was added at a mass ratio of 1:10. The mixture was steamed at 100°C for 30 minutes, and then centrifuged (speed 1200 rpm, time 3 minutes). The precipitate was mixed with 50°C water at a mass ratio of 1:2 and stirred. The pH was adjusted to 5 with a mass concentration of 5% sulfuric acid solution. A cellulase solution with an activity of 25 U / ml was added at a volume ratio of 100:1. The mixture was reacted at 50°C for 3 days, and then centrifuged (speed 2000 rpm, time 10 minutes). The supernatant was inoculated with 10% inoculum of Acetobacter xylinum for fermentation and culture. The mixture was fermented at 30°C for 7 days. The bacterial cellulose was collected, washed with deionized water 3 times, and freeze-dried at -50°C for 48 hours to obtain a BC membrane. The BC membrane was then processed into straws by hot pressing (temperature 120°C, pressure 5 MPa, time 10 minutes) to obtain BC membrane straws.

[0058] S2. BC membrane straw pretreatment: The prepared BC membrane straw was placed in a 2% sodium hydroxide solution at 45°C for 12 minutes, removed and rinsed with deionized water five times, then placed in a 1% vinyltrimethoxysilane solution at 35°C for 8 minutes, removed and dried at room temperature to obtain a pretreated BC membrane straw;

[0059] S3. Preparation of fluorocarbon resin solution: polyvinylidene fluoride was dissolved in an ethanol-water mixed solvent (the volume ratio of ethanol to water was 7:3), with the mass ratio of polyvinylidene fluoride to the ethanol-water mixed solvent being 1:13. The mixture was stirred at 30° C. and 500 rpm for 2 hours to obtain a fluorocarbon resin solution.

[0060] S4, coating with fluorocarbon resin solution: vertically immerse the pretreated BC membrane straw in the fluorocarbon resin solution for 3 minutes, and then rotate the straw at 100 rpm for 1.5 minutes to form a coated BC membrane straw;

[0061] S5. Drying and curing: Place the coated BC film straw in a vacuum drying oven, first dry it at 55°C for 40 minutes, then heat it to 160°C, and cure it at a vacuum degree of -0.07 MPa for 1.5 hours to obtain a fluorocarbon resin film reinforced BC film straw.

[0062] Comparative Example 3

[0063] A method for enhancing the hydrophobicity of a BC film straw using a fluorocarbon resin film comprises the following steps:

[0064] S1. Preparation of BC membrane straws: corn straw was crushed and sieved (pore size 6 mm), the undersize powder was collected, and a 2% NaOH solution was added at a mass ratio of 1:10. The mixture was steamed at 100°C for 30 minutes, and then centrifuged (speed 1200 rpm, time 3 minutes). The precipitate was mixed with 50°C water at a mass ratio of 1:2 and stirred. The pH was adjusted to 5 with a mass concentration of 5% sulfuric acid solution. A cellulase solution with an activity of 25 U / ml was added at a volume ratio of 100:1. The mixture was reacted at 50°C for 3 days, and then centrifuged (speed 2000 rpm, time 10 minutes). The supernatant was inoculated with 10% inoculum of Acetobacter xylinum for fermentation and culture. The mixture was fermented at 30°C for 7 days. The bacterial cellulose was collected, washed with deionized water 3 times, and freeze-dried at -50°C for 48 hours to obtain a BC membrane. The BC membrane was then processed into straws by hot pressing (temperature 120°C, pressure 5 MPa, time 10 minutes) to obtain BC membrane straws.

[0065] S2. BC membrane straw pretreatment: The prepared BC membrane straw was placed in a 2% sodium hydroxide solution at 45°C for 12 minutes, removed and rinsed with deionized water five times, then placed in a 1% vinyltrimethoxysilane solution at 35°C for 8 minutes, removed and dried at room temperature to obtain a pretreated BC membrane straw;

[0066] S3. Preparation of fluorocarbon resin solution: polyvinylidene fluoride was dissolved in an ethanol-water mixed solvent (the volume ratio of ethanol to water was 7:3), with the mass ratio of polyvinylidene fluoride to the ethanol-water mixed solvent being 1:13. The mixture was stirred at 30° C. and 500 rpm for 2 hours to obtain a fluorocarbon resin solution.

[0067] S4, coating with fluorocarbon resin solution: vertically immerse the pretreated BC membrane straw in the fluorocarbon resin solution for 3 minutes, and then rotate the straw at 100 rpm for 1.5 minutes to form a coated BC membrane straw;

[0068] S5. Drying and curing: Place the coated BC film straw in a vacuum drying oven, first dry it at 55°C for 40 minutes, then heat it to 135°C, and cure it at a vacuum degree of -0.05MPa for 1.5 hours to obtain a fluorocarbon resin film reinforced BC film straw.

[0069] Performance Testing

[0070] Functionality tests were performed on the fluorocarbon resin film reinforced BC film straws prepared in Examples 1-3 and Comparative Examples 1-3.

[0071] Hydrophobicity test: The fluorocarbon resin film-reinforced BC film straws prepared in Examples 1-3 and Comparative Examples 1-3 were immersed in cola for 4 hours, and the water contact angles on the straw surfaces were measured.

[0072] Strength retention test: Referring to the GB / T 1040.3-2006 standard, the straws' initial tensile strength (σ0) and tensile strength after four hours of cola immersion (σ1) were tested. The straws' strength retention was calculated using the formula. The test results are shown in Table 1.

[0073] Strength retention rate = σ1 / σ0 × 100%

[0074] Table 1

[0075] contact angle Strength retention rate% Example 1 138° 85 Example 2 145° 92 Example 3 132° 81 Comparative Example 1 115° 70 Comparative Example 2 112° 68 Comparative Example 3 121° 75

[0076] As can be seen from Table 1, the fluorocarbon resin membrane reinforced BC membrane straws prepared in the examples of the present application have excellent hydrophobicity and high strength retention rate, especially Example 2 has the best effect; compared with Example 2, the mass ratio of polyvinylidene fluoride to ethanol-water mixed solvent in Control Example 1 is 1:8, and the concentration of the fluorocarbon resin solution is increased. The test results show that the hydrophobicity and strength retention rate of the fluorocarbon resin membrane reinforced BC membrane straws prepared in Control Example 1 are not as good as those in Example 2, indicating that the coating amount range of this application is the optimal range; compared with Example 2, the curing temperature of Control Example 2 is increased to 160°C. The test results show that the hydrophobicity of the fluorocarbon resin membrane reinforced BC membrane straws prepared in Control Example 2 is not as good as that of Example 2, and the strength retention rate is not as good as that of Example 2, indicating that the curing temperature range of this application is the optimal temperature range; compared with Example 3, the vacuum degree during curing in Control Example 3 is set to -0.05MPa. The test results show that the hydrophobicity of the fluorocarbon resin membrane reinforced BC membrane straws prepared in Control Example 3 is not as good as that of Example 2, and the strength retention rate is lower than that of Example 2, indicating that the curing pressure range used in this embodiment is the optimal range.

[0077] In summary, the fluorocarbon resin film reinforced BC film straws prepared in the examples of the present application have excellent hydrophobic properties and high strength retention rate, especially Example 2 has the best effect. The best example of the present application is Example 2.

[0078] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in similar ways. As long as they do not deviate from the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A method for enhancing the hydrophobicity of BC membrane straws using fluorocarbon resin membranes, characterized in that: The steps include: S1. Preparation of BC membrane straws: corn stalks are crushed, an alkaline solution is added, the mixture is steamed, and the mixture is centrifuged. The precipitate is stirred with water, the pH is adjusted to acidic, cellulase is added, and the mixture is centrifuged. The supernatant is inoculated with Acetobacter xylinum for fermentation. The bacterial cellulose is then collected, washed, and dried to produce a BC membrane, which is then processed into straws to obtain BC membrane straws. S2. Pretreatment of BC membrane straws: soaking the prepared BC membrane straws in an alkaline solution, taking them out and washing them, then soaking them in a silane coupling agent solution, taking them out and drying them, to obtain pretreated BC membrane straws; S3, preparation of fluorocarbon resin solution: dissolving fluorocarbon resin in ethanol-water mixed solvent and stirring to obtain fluorocarbon resin solution; S4, coating with fluorocarbon resin solution: immerse the pretreated BC membrane straw in the fluorocarbon resin solution for 2-3 minutes, then rotate the straw to form a fluorocarbon resin liquid film to obtain a coated BC membrane straw; S5. Drying and curing: The coated BC film straw is placed in a vacuum drying oven for drying, and then heated and cured under vacuum conditions to obtain a fluorocarbon resin film reinforced BC film straw.

2. The method of using a fluorocarbon resin film to enhance the hydrophobicity of a BC film straw according to claim 1, characterized in that: The alkaline solution is a sodium hydroxide solution or a potassium hydroxide solution.

3. The method of using a fluorocarbon resin film to enhance the hydrophobicity of a BC film straw according to claim 1, characterized in that: The silane coupling agent is one of γ-aminopropyltriethoxysilane, vinyltrimethoxysilane and γ-methacryloyloxytrimethoxysilane.

4. The method of using a fluorocarbon resin film to enhance the hydrophobicity of a BC film straw according to claim 1, characterized in that: The fluorocarbon resin is one of polyvinylidene fluoride, ethylene-tetrafluoroethylene copolymer and polytetrafluoroethylene.

5. The method of using a fluorocarbon resin film to enhance the hydrophobicity of a BC film straw according to claim 1, characterized in that: The mass ratio of the fluorocarbon resin to the ethanol-water mixed solvent is 1:10-15.

6. The method of using a fluorocarbon resin film to enhance the hydrophobicity of a BC film straw according to claim 1, characterized in that: The rotation in step S4 has a rotation speed of 80-120 rpm.

7. The method of using a fluorocarbon resin film to enhance the hydrophobicity of a BC film straw according to claim 1, characterized in that: The temperature of the vacuum drying oven is 50-60° C. and the drying time is 30-45 minutes.

8. The method of using a fluorocarbon resin film to enhance the hydrophobicity of a BC film straw according to claim 1, characterized in that: In step S5, the temperature is raised to 120-150°C.

9. The method of using a fluorocarbon resin film to enhance the hydrophobicity of a BC film straw according to claim 1, characterized in that: The vacuum degree of step S5 is -0.08 to -0.06 MPa.

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