Nanofiber textured superhydrophobic high-breathable biomass medical mask material and preparation method thereof

Abstract

The application discloses a kind of nanofiber texture super-hydrophobic high-breath biomaterial medical mask and preparation method thereof, regular micro-nano composite reticular porous structure layer formed by the arrangement of hollow microfilament containing mesoporous structure, and the surface of hollow microfilament containing mesoporous structure is attached with super-hydrophobic layer;The material of hollow microfilament containing mesoporous structure includes chitosan, sodium alginate, polyvinyl alcohol and ramie fiber, and the mass ratio of chitosan, sodium alginate, polyvinyl alcohol and ramie fiber is 30-45:5-12:5-10:50-70.

Description

Technical Field

[0001] This invention belongs to the field of medical masks, specifically relating to a biomass medical mask material with a nanofiber texture that is superhydrophobic and highly breathable, and its preparation method. Background Technology

[0002] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art.

[0003] Medical protective masks typically have a three-layer SMS (Superficial Membrane Filter) structure. The middle layer, ultra-fine meltblown polypropylene fiber, is the primary filter layer for bacteria and viruses. However, these masks have the following drawbacks requiring improvement: 1) Polypropylene is a non-degradable polymer, making medical mask waste difficult to dispose of. As disposable products, widespread use poses environmental problems. 2) Existing medical protective masks often use solid meltblown fibers in their filter layers. These fibers are not breathable, and their high-density arrangement reduces breathability. 3) While the surface material of existing medical protective masks is hydrophobic, it lacks superhydrophobic properties. Prolonged contact with liquids on the outer surface allows small droplets to penetrate the inner layer, potentially causing infection. These masks require periodic replacement, posing a potential safety hazard. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a biomass medical mask with a nanofiber texture that is superhydrophobic and highly breathable, and its preparation method. This medical mask material has the characteristics of high breathability, superhydrophobicity, antibacterial properties, and biodegradability, and has good practical effectiveness and application value.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0006] In a first aspect, the present invention provides a biomass medical mask material with nanofiber textured superhydrophobic and highly breathable structure, which is a regular micro-nano composite mesh porous structure layer formed by the arrangement of hollow microfilaments containing mesoporous structure, and the surface of the hollow microfilaments containing mesoporous structure is attached with a superhydrophobic layer.

[0007] The hollow microfilaments containing mesoporous structures are made of chitosan, sodium alginate, polyvinyl alcohol, and ramie fiber, with a mass ratio of 30-45:5-12:5-10:50-70.

[0008] In some embodiments, the hollow microfilaments have an outer diameter of 400-500 nm, an inner diameter of 300-400 nm, and a mesopore size of 20-40 nm.

[0009] Secondly, the present invention provides a method for preparing a biomass medical mask material with a nanofiber texture that is superhydrophobic and highly breathable, comprising the following steps:

[0010] Ramie fiber is subjected to low-alkali high-temperature cooking to obtain nano-sized ramie fiber slurry;

[0011] Chitosan, sodium alginate, and polyvinyl alcohol were added to the nano-sized slurry of ramie fiber in a certain proportion and stirred for 1-3 hours to obtain a mixed slurry.

[0012] A diluent, namely acetylated tributyl citrate or tributyl citrate, is added to the mixed slurry to obtain a homogeneous biomass solution.

[0013] In the homogenized biomass solution, the mass ratio of chitosan, sodium alginate, polyvinyl alcohol, ramie fiber, diluent, and water is 30-45:5-12:5-10:50-70:1-5:200-260.

[0014] The electrospinning nozzle has a three-layer sleeve structure from the inside to the outside. During electrospinning, a high-speed airflow is introduced into the inner sleeve, a biomass homogeneous solution is introduced between the middle and inner sleeves, and a hot airflow is introduced between the outer and middle sleeves to prepare hollow microfilaments containing mesopores.

[0015] Hollow microfilaments are arranged on a micron-structured spinning template to form a regular micro-nano composite network porous structure layer;

[0016] Finally, the surface of the micro-nano composite network porous layer was treated with superhydrophobicity using low-temperature plasma-enhanced chemical vapor deposition to obtain medical mask material.

[0017] The role of chitosan: As a matrix, chitosan plays an antibacterial role.

[0018] The role of sodium alginate: It acts as a binder and stabilizer, binding several other substances together, while also having good biocompatibility.

[0019] The role of polyvinyl alcohol: to improve fiber bonding strength.

[0020] The function of ramie fiber: As the structural framework of fibers, it plays a reinforcing role.

[0021] The role of diluent: phase separating agent, to prepare mesoporous structures.

[0022] In some embodiments, the temperature for the low-alkali high-temperature cooking treatment of ramie fibers is 95-100°C, the concentration of NaOH in the alkali solution is 0.3-0.7wt%, and the cooking time is 60-120min.

[0023] The purpose of low-alkali high-temperature cooking is to remove impurities such as wax, ash, and pectin from the surface of ramie fibers.

[0024] Preferably, after the ramie fiber is steamed, it is washed with clean water 2-4 times, soaked at 60-80℃ for 12-24 hours, and then milled 15-20 times using a colloid mill to prepare nano-sized ramie fiber slurry.

[0025] The purpose of soaking is to soften the ramie fiber structure, which is beneficial for the next step of grinding it into nanofiber slurry using a colloid mill.

[0026] In some embodiments, the electrospinning nozzle consists of three sleeves with a wall thickness of 1 mm. The inner sleeve through which the high-speed airflow passes has an inner diameter of 3-5 mm, the middle sleeve through which the bio-based slurry passes has an inner diameter of 6-8 mm, and the outer sleeve through which the hot airflow passes has an inner diameter of 9-11 mm.

[0027] Preferably, the velocity of the high-speed airflow is 8-12 m / s; the velocity of the biomass homogenized solution is 7-11 m / s; and the temperature of the hot airflow is 80-160°C.

[0028] The high-speed airflow forms a hollow structure in the middle of the fiber, while simultaneously propelling the fiber forward and improving spinning efficiency.

[0029] The role of the hot air flow is to achieve phase separation, allowing the diluent to separate out during fiber formation to form mesopores.

[0030] In some embodiments, the thickness of the regular micro-nano composite mesh porous structure layer is 500-600 μm, and the pore size is 1-5 μm.

[0031] Thirdly, the present invention provides a medical mask, the body of which is made of the aforementioned nanofiber-textured superhydrophobic and highly breathable biomass medical mask material.

[0032] The beneficial effects achieved by one or more embodiments of the present invention described above are as follows:

[0033] Unlike existing masks that use polypropylene, this invention uses natural biomass materials to prepare medical protective masks, which are fully biodegradable and produce green and pollution-free waste; the material achieves high breathability by utilizing a reasonable composite microstructure.

[0034] A hydrophobic layer is prepared on the material surface by low-temperature plasma-enhanced vapor deposition to achieve superhydrophobicity of the material surface, thus realizing the synergistic existence of high air permeability and superhydrophobicity.

[0035] Furthermore, conventional nanofibers are solid fibers and lack air permeability. This invention integrates electrospinning-phase separation composite technology and microfluidics (a three-layer sleeve structure, with different fluids in each sleeve, the inner layer being a high-speed airflow, the middle layer being a bio-based slurry, and the outer layer being a high-temperature airflow) to design an electrospinning combined jet nozzle, which prepares hollow nanofibers with smaller mesoporous structures on the outer wall of the fibers. The fibers themselves are air permeable, greatly improving the air permeability of the fabric. Attached Figure Description

[0036] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0037] Figure 1 This is a process diagram of the preparation of a biomass medical protective mask with a micro-nano composite mesh structure according to an embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of electrospinning of a microfluidic combined jet nozzle according to an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the hollow microfilament containing a mesoporous structure according to an embodiment of the present invention;

[0040] Figure 4 In the text, a is the physical object of the nanofiber textured superhydrophobic and highly breathable biomass medical mask material prepared in the embodiments of the present invention; b is the water contact angle of the mask material at different pH values;

[0041] Figure 5 In the diagram, a is a schematic diagram of the test principle for air permeability testing using the YG(B)461G fabric air permeability tester; b is the air permeability test platform. Detailed Implementation

[0042] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0043] The present invention will be further described below with reference to the embodiments.

[0044] Example 1

[0045] Preparation method of biomass medical mask material with nanofiber texture, superhydrophobic and highly breathable, such as Figure 1 As shown, it includes the following steps:

[0046] (1) Ramie fiber was selected and subjected to low-alkali high-temperature cooking treatment. The high temperature was 100℃, the low alkali was 0.5wt% NaOH solution, the cooking time was 60 minutes, the cooked plant fiber was washed with water 3 times, soaked at 60℃ for 12 hours, and then milled 15 times using a Super Masscolloider to prepare ramie fiber nano-sized slurry.

[0047] (2) Weigh out chitosan, sodium alginate and polyvinyl alcohol, put them into ramie fiber nano-slurry, and stir evenly for 2 hours using a magnetic stirrer.

[0048] (3) Weigh out the diluent acetyl tributyl citrate (ATBC) according to the weight ratio, put it into the mixed solution in step (2), and stir it quickly for 1 hour using a magnetic stirrer.

[0049] The mass ratio of chitosan, sodium alginate, polyvinyl alcohol, ramie fiber, diluent, and water is 30:5:6:50:1:200.

[0050] (4) Place the mixed slurry from step (3) into an electrospinning machine with a specially structured nozzle, such as... Figure 2 As shown, hollow microfilaments with mesoporous structures are prepared using electrospinning-phase separation composite technology. The electrospinning nozzle has a three-layer sleeve structure from the inside to the outside. During electrospinning, a high-speed airflow is introduced into the inner sleeve, a homogeneous biomass solution is introduced between the middle and inner sleeves, and a hot airflow is introduced between the outer and middle sleeves.

[0051] The high-speed airflow has a velocity of 10 m / s; the biomass homogenization solution has a velocity of 10 m / s; and the hot airflow has a temperature of 150°C.

[0052] Hollow microfilaments containing mesoporous structures, such as Figure 3 As shown, thermal energy is an important parameter that causes phase separation. As the temperature decreases, the polymer gradually solidifies, and the diluent also separates from the homogeneous system, thereby forming a large number of mesoporous structures on the hollow fiber wall.

[0053] (5) The hollow microfilaments prepared in step (4) are arranged on a micron-structured spinning template to form a regular micro-nano composite porous structure. The thickness of the regular micro-nano composite porous structure layer is 500-600 μm, and the pore size is 1-5 μm.

[0054] Finally, the surface of the dressing was treated with superhydrophobicity by low-temperature plasma-enhanced chemical vapor deposition, and the micro-scale interface effect of the hydrophobic surface was used to obtain a medical protective mask material with synergistic superhydrophobicity and high breathability.

[0055] The prepared nanofiber textured superhydrophobic and highly breathable biomass medical mask material is shown in the image.Figure 4 As shown in (a), its water contact angle at different pH values ​​is as follows: Figure 4 As shown in (b), the results show that the water contact angle at different pH values ​​is greater than 150°, indicating that it has obvious superhydrophobic characteristics.

[0056] In addition, its air permeability was tested using a YG(B)461G fabric air permeability tester. The test principle is as follows: Figure 5 As shown, under a pressure difference of 100Pa, the gas flow rate passing through the sample surface within a certain time was measured. The test results showed that its air permeability reached 2600mm / s, indicating high air permeability.

[0057] Example 2

[0058] Preparation method of biomass medical mask material with nanofiber texture, superhydrophobic and highly breathable, such as Figure 1 As shown, it includes the following steps:

[0059] (1) Ramie fiber was selected and subjected to low-alkali high-temperature cooking treatment. The high temperature was 100℃, the low alkali was 0.5wt% NaOH solution, and the cooking time was 120 minutes. After cooking, the plant fiber was washed with water 4 times, soaked at 70℃ for 20 hours, and then milled 20 times using a Super Masscolloider to prepare ramie fiber nano-sized slurry.

[0060] (2) Weigh out chitosan, sodium alginate and polyvinyl alcohol, put them into ramie fiber nano-slurry, and stir evenly for 2 hours using a magnetic stirrer.

[0061] (3) Weigh out the diluent acetyl tributyl citrate (ATBC) according to the weight ratio, put it into the mixed solution in step (2), and stir it quickly for 1 hour using a magnetic stirrer.

[0062] The mass ratio of chitosan, sodium alginate, polyvinyl alcohol, ramie fiber, diluent, and water is 45:10:10:60:4:250.

[0063] (4) Place the mixed slurry from step (3) into an electrospinning machine with a specially structured nozzle, such as... Figure 2 As shown, hollow microfilaments with mesoporous structures are prepared using electrospinning-phase separation composite technology. The electrospinning nozzle has a three-layer sleeve structure from the inside to the outside. During electrospinning, a high-speed airflow is introduced into the inner sleeve, a homogeneous biomass solution is introduced between the middle and inner sleeves, and a hot airflow is introduced between the outer and middle sleeves.

[0064] The high-speed airflow has a velocity of 8 m / s; the biomass homogenization solution has a velocity of 11 m / s; and the hot airflow has a temperature of 130°C.

[0065] Hollow microfilaments containing mesoporous structures, such as Figure 3 As shown, thermal energy is an important parameter that causes phase separation. As the temperature decreases, the polymer gradually solidifies, and the diluent also separates from the homogeneous system, thereby forming a large number of mesoporous structures on the hollow fiber wall.

[0066] (5) The hollow microfilaments prepared in step (4) are arranged on a micron-structured spinning template to form a regular micro-nano composite porous structure. The thickness of the regular micro-nano composite porous structure layer is 550-600 μm, and the pore size is 2-4 μm.

[0067] Finally, the surface of the dressing was treated with superhydrophobicity by low-temperature plasma-enhanced chemical vapor deposition, and the micro-scale interface effect of the hydrophobic surface was used to obtain a medical protective mask material with synergistic superhydrophobicity and high breathability.

[0068] Example 3

[0069] A method for preparing a biomass medical mask material with a nanofiber texture that is superhydrophobic and highly breathable includes the following steps:

[0070] (1) Ramie fiber was selected and subjected to low-alkali high-temperature cooking treatment. The high temperature was 100℃, the low alkali was 0.5wt% NaOH solution, the cooking time was 100 minutes, the cooked plant fiber was washed with water 4 times, soaked at 80℃ for 24 hours, and milled 18 times using a Super Masscolloider to prepare ramie fiber nano-sized slurry.

[0071] (2) Weigh out chitosan, sodium alginate and polyvinyl alcohol, put them into ramie fiber nano-slurry, and stir evenly for 2 hours using a magnetic stirrer.

[0072] (3) Weigh out the diluent acetyl tributyl citrate (ATBC) according to the weight ratio, put it into the mixed solution in step (2), and stir it quickly for 1 hour using a magnetic stirrer.

[0073] The mass ratio of chitosan, sodium alginate, polyvinyl alcohol, ramie fiber, diluent, and water is 40:12:8:70:5:260.

[0074] (4) Place the mixed slurry from step (3) into an electrospinning machine with a specially structured nozzle, such as... Figure 2 As shown, hollow microfilaments with mesoporous structures are prepared using electrospinning-phase separation composite technology. The electrospinning nozzle has a three-layer sleeve structure from the inside to the outside. During electrospinning, a high-speed airflow is introduced into the inner sleeve, a homogeneous biomass solution is introduced between the middle and inner sleeves, and a hot airflow is introduced between the outer and middle sleeves.

[0075] The high-speed airflow has a velocity of 12 m / s; the biomass homogenization solution has a velocity of 8 m / s; and the hot airflow has a temperature of 90°C.

[0076] Hollow microfilaments containing mesoporous structures, such as Figure 3 As shown, thermal energy is an important parameter that causes phase separation. As the temperature decreases, the polymer gradually solidifies, and the diluent also separates from the homogeneous system, thereby forming a large number of mesoporous structures on the hollow fiber wall.

[0077] (5) The hollow microfilaments prepared in step (4) are arranged on a micron-structured spinning template to form a regular micro-nano composite porous structure. The thickness of the regular micro-nano composite porous structure layer is 500-550 μm, and the pore size is 1-4 μm.

[0078] Finally, the surface of the dressing was treated with superhydrophobicity by low-temperature plasma-enhanced chemical vapor deposition, and the micro-scale interface effect of the hydrophobic surface was used to obtain a medical protective mask material with synergistic superhydrophobicity and high breathability.

[0079] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a nanofiber textured superhydrophobic and highly breathable biomass medical mask material, characterized in that: Includes the following steps: Ramie fiber is subjected to low-alkali high-temperature cooking to obtain nano-sized ramie fiber pulp. Chitosan, sodium alginate, and polyvinyl alcohol were added to the nano-sized slurry of ramie fiber in a certain proportion and stirred for 1-3 hours to obtain a mixed slurry. A diluent, namely acetylated tributyl citrate or tributyl citrate, is added to the mixed slurry to obtain a homogeneous biomass solution. In the homogenized biomass solution, the mass ratio of chitosan, sodium alginate, polyvinyl alcohol, ramie fiber, diluent, and water is 30-45:5-12:5-10:50-70:1-5:200-260. The electrospinning nozzle has a three-layer sleeve structure from the inside to the outside. During electrospinning, a high-speed airflow is introduced into the inner sleeve, a biomass homogeneous solution is introduced between the middle and inner sleeves, and a hot airflow is introduced between the outer and middle sleeves to prepare hollow microfilaments containing mesopores. Hollow microfilaments are arranged on a micron-structured spinning template to form a regular micro-nano composite network porous structure layer; Finally, the surface of the micro-nano composite network porous layer was treated with superhydrophobicity using low-temperature plasma-enhanced chemical vapor deposition to obtain medical mask material. The medical mask material is a regular micro-nano composite mesh porous structure layer formed by the arrangement of hollow microfilaments containing mesoporous structures, and a superhydrophobic layer is attached to the surface of the hollow microfilaments containing mesoporous structures. The hollow microfilaments containing mesoporous structures are made of materials including chitosan, sodium alginate, polyvinyl alcohol, and ramie fiber.

2. The method for preparing the nanofiber textured superhydrophobic and highly breathable biomass medical mask material according to claim 1, characterized in that: The hollow microfilaments have an outer diameter of 400-500 nm, an inner diameter of 300-400 nm, and a mesopore size of 20-40 nm.

3. The method for preparing the nanofiber textured superhydrophobic and highly breathable biomass medical mask material according to claim 1, characterized in that: The temperature for low-alkali high-temperature cooking of ramie fiber is 95-100℃, the concentration of NaOH in the alkali solution is 0.3-0.7wt%, and the cooking time is 60-120min.

4. The method for preparing the nanofiber textured superhydrophobic and highly breathable biomass medical mask material according to claim 3, characterized in that: After the ramie fiber is cooked, it is washed with clean water 2-4 times, soaked at 60-80℃ for 12-24 hours, and then milled 15-20 times using a colloid mill to prepare nano-sized ramie fiber slurry.

5. The method for preparing the nanofiber textured superhydrophobic and highly breathable biomass medical mask material according to claim 1, characterized in that: The electrostatic spinning nozzle consists of three sleeves with a wall thickness of 1 mm. The inner sleeve through which the high-speed airflow passes has an inner diameter of 3-5 mm, the middle sleeve through which the bio-based slurry passes has an inner diameter of 6-8 mm, and the outer sleeve through which the hot airflow passes has an inner diameter of 9-11 mm.

6. The method for preparing the nanofiber textured superhydrophobic and highly breathable biomass medical mask material according to claim 1, characterized in that: The high-speed airflow has a velocity of 8-12 m / s; the biomass homogenization solution has a velocity of 7-11 m / s; and the hot airflow has a temperature of 80-160℃.

7. The method for preparing the nanofiber textured superhydrophobic and highly breathable biomass medical mask material according to claim 1, characterized in that: The thickness of the micro-nano composite mesh porous structure layer is 500-600 μm, and the pore size is 1-5 μm.

8. The method for preparing the nanofiber textured superhydrophobic and highly breathable biomass medical mask material according to claim 1, characterized in that: Low-temperature plasma-enhanced chemical vapor deposition method is used to treat the surface of micro-nano composite network porous layers with superhydrophobicity.

9. A medical mask, characterized in that: The material of the mask body is the nanofiber textured superhydrophobic and highly breathable biomass medical mask material obtained by the preparation method described in claim 1.

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