Antibacterial sanitary napkin packaging bag and method for manufacturing the same

Abstract

The application discloses an antibacterial sanitary napkin packaging bag and a preparation method thereof. The antibacterial sanitary napkin packaging bag comprises a substrate layer, an antibacterial layer and a leakage-proof layer. The substrate layer is made of modified polylactic acid, polybutylene adipate and the like, and contains a degradation promoter. The antibacterial layer contains nano-montmorillonite loaded with antibacterial peptides, chitosan and the like, and silk gourd reticular fiber is used for slow release. The leakage-proof layer is a film of ethylene-vinyl acetate copolymer and modified silicon dioxide, and gas-permeable micropores are arranged on the film. The preparation method comprises steps such as substrate layer forming and antibacterial layer coating, and the process parameters of each layer are accurately controlled. Through the cooperation of the three layers, the antibacterial rate of the packaging bag to escherichia coli and staphylococcus aureus is more than 99% in 24 hours, the degradation rate is more than 88% in 83 days, and the oxygen transmission rate is 4.5-5.2 cm 3 / (m 2 24h0.1MPa). The antibacterial sanitary napkin packaging bag has the advantages of long-acting antibacterial property, air permeability, leakage prevention, environmental protection, degradation and good mechanical property, and is suitable for the storage and use requirements of sanitary napkins.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bio-based composite materials, in particular to an antibacterial sanitary napkin packaging bag and a preparation method thereof. BACKGROUND

[0002] With the improvement of women's health awareness and the tightening of environmental protection policies, sanitary napkin packaging bags need to meet the requirements of antibacterial protection, environmental degradation and use adaptability, but the existing technology still has obvious shortcomings.

[0003] In terms of antibacterial performance, traditional packaging relies on single chemical bacteriostatic agents or basic antibacterial ingredients, which not only have short antibacterial duration, but also easily lead to microbial drug resistance, making it difficult to continuously block microbial invasion within the shelf life and posing a risk of content contamination.

[0004] In terms of environmental protection, the existing degradable packaging substrate is mostly ordinary degradable resin, which has a slow degradation rate, and some degradation products may cause environmental burden, and cannot meet the high environmental protection requirements under the "plastic reduction" policy.

[0005] In terms of use performance, the existing design often falls into the dilemma of "leakage prevention and air permeability": excessive emphasis on barrier properties can lead to insufficient air permeability in the bag, which can breed microorganisms; while simply increasing the air permeability structure can cause liquid leakage risk, making it difficult to balance storage protection and use experience.

[0006] In addition, the upgrading of regulatory standards has included such packaging in stricter safety management, and has put forward higher requirements for sterile barriers and biocompatibility, so the existing technology needs to be broken through to meet multiple requirements. SUMMARY

[0007] The present application provides an antibacterial sanitary napkin packaging bag and a preparation method thereof, which realizes antibacterial storage and use adaptability of sanitary napkins through the synergistic effect of the degradation of the substrate layer, the long-acting antibacterial property of the antibacterial layer and the leakage-proof and air-permeable property of the leakage-proof layer, avoids the deterioration of sanitary napkins due to microbial breeding during storage, and at the same time meets the air permeability demand during use, preventing the internal moisture of the packaging bag from causing the performance of the sanitary napkin to decline.

[0008] To achieve the above-mentioned purposes, the technical solutions adopted by the present application are as follows:

[0009] The application discloses an antibacterial sanitary napkin packaging bag, which comprises a substrate layer, an antibacterial layer and a leakage-proof layer which are sequentially compounded; the substrate layer is prepared by blending modified polylactic acid, polybutylene adipate, nano-titanium dioxide and tributyl citrate according to weight proportions of 60-80, 20-30, 3-5 and 1-2; the antibacterial layer is prepared by compounding nano-montmorillonite loaded with antibacterial peptides, chitosan, polyvinyl alcohol and silane coupling agent according to weight proportions of 10-15, 5-8, 2-4 and 0.5-1; the leakage-proof layer is prepared by blending ethylene-vinyl acetate copolymer and modified silicon dioxide according to weight proportions of 80-90 and 10-20, and the surface of the leakage-proof layer is provided with uniformly distributed air-permeable micropores with a pore size of 5-10 mu m; and the preparation method of the antibacterial sanitary napkin packaging bag comprises the steps of substrate layer forming, antibacterial layer coating, leakage-proof layer compounding, micropore processing, heat sealing forming and sterilization treatment.

[0010] Further, the antibacterial layer further comprises loofah fiber with a weight proportion of 1-3; the loofah fiber is pretreated in a sodium hydroxide solution with a mass concentration of 5-8% for 2-3 hours, and then is mixed with nano-montmorillonite loaded with antibacterial peptides and chitosan, so that the adsorption of the antibacterial layer is enhanced and the slow-release effect of the antibacterial components is improved through the porous structure of the loofah fiber.

[0011] Preferably, the modified silicon dioxide in the leakage-proof layer is nano-silicon dioxide modified by gamma-aminopropyl triethoxysilane, and the particle size of the modified silicon dioxide is 20-50 nm; the compatibility of the nano-silicon dioxide and the ethylene-vinyl acetate copolymer is enhanced through the modification of the silane coupling agent, and the structural stability of the leakage-proof layer is improved.

[0012] Preferably, the substrate layer further comprises a degradation promoter with a weight proportion of 0.8-1.5; the degradation promoter is prepared by mixing polyethylene glycol, organic acid and organic montmorillonite according to weight proportions of 1-2, 0.3-0.5 and 0.2-0.4; the degradation rate of the substrate layer in a natural environment is accelerated through the degradation promoter, and the environmental residue is reduced.

[0013] Preferably, the thickness of the antibacterial layer is 5-10 mu m, the thickness of the substrate layer is 20-30 mu m, the thickness of the leakage-proof layer is 15-25 mu m, and the total thickness of the three layers after compounding is 40-65 mu m; the balance between the lightness and the mechanical properties of the packaging bag is achieved by controlling the thicknesses of the layers, and the use convenience is avoided from being affected by the excessive thickness or the damage is avoided from being caused by the excessive thinness.

[0014] A preparation method of an antibacterial sanitary napkin packaging bag comprises the following steps.

[0015] S1: Base material layer preparation, modified polylactic acid, polybutylene adipate, nano-titanium dioxide and tributyl citrate were added to a high-speed mixer according to the ratio, mixed at a speed of 800-1000 r / min for 15-20 min, then the mixture was added to a twin-screw extruder, the temperature of each zone of the screw was controlled at 160-165°C (zone 1), 165-170°C (zone 2), 170-175°C (zone 3), and 175-180°C (die), the screw speed was 300-400 r / min, after extrusion and granulation, the film was calendered by a calender to obtain the base material layer;

[0016] S2: Antimicrobial layer coating, the antimicrobial peptide-loaded nano-montmorillonite, chitosan, polyvinyl alcohol and silane coupling agent were mixed according to the ratio, deionized water was added to adjust the solid content to 30-40%, an antimicrobial slurry was prepared, the antimicrobial slurry was coated on one side surface of the base material layer by a doctor blade coating method, the coating thickness was controlled at 5-10 μm, then dried at 80-90°C for 1-2 h to form an antimicrobial layer;

[0017] S3: Leakage-proof layer compounding, ethylene-vinyl acetate copolymer and modified silica were mixed according to the ratio, melted and extruded into a film at 150-170°C to obtain a leakage-proof layer, the leakage-proof layer was aligned with the side surface of the antimicrobial layer away from the base material layer, and the two layers were compounded by a hot press compounding machine, the hot press temperature was controlled at 120-130°C, the pressure was 0.3-0.5 MPa, and the compounding time was 30-60 s;

[0018] S4: Micropore processing, a laser drilling device was used to process breathable micropores on the surface of the leakage-proof layer, the drilling speed was set at 100-150 holes / min, the hole spacing was 0.5-1 mm, and an optical sensor was used to monitor the micropore diameter to ensure that the diameter was maintained at 5-10 μm;

[0019] S5: Heat sealing and molding, the compounded film material was cut into a predetermined shape according to the size of the sanitary napkin, and the edges of the film material were heat sealed by a heat sealing machine, the heat sealing temperature was controlled at 130-140°C, the heat sealing time was 1-2 s, and the heat sealing width was 2-3 mm;

[0020] S6: Sterilization treatment, the heat-sealed and molded packaging bag was placed in a UV sterilization box, the UV intensity was set at 200-300 μW / cm², the sterilization time was 15-20 min, and after sterilization, the packaging bag was naturally cooled to room temperature to obtain an antibacterial sanitary napkin packaging bag.

[0021] Further, the preparation of the antimicrobial layer comprises the following steps:

[0022] S1: Nano-montmorillonite modification, nano-montmorillonite is added to a hydrochloric acid solution with a mass concentration of 10-15%, the solid-liquid ratio is 1:10-1:15, stirring at 60-70℃ for 2-3h, then filtering, washing the filter residue with deionized water until neutral, drying at 100-110℃ for 4-5h to obtain acidified nano-montmorillonite;

[0023] S2: Antimicrobial peptide loading, dissolving the antimicrobial peptide in deionized water to prepare an antimicrobial peptide solution with a mass concentration of 0.5-1%, adding the acidified nano-montmorillonite to the antimicrobial peptide solution, the solid-liquid ratio is 1:20-1:30, stirring at 30-40℃ for 4-5h, then centrifugal separation, drying at 80-90℃ for 3-4h to obtain nano-montmorillonite loaded with antimicrobial peptide;

[0024] S3: Chitosan solution preparation, adding chitosan to an acetic acid solution with a mass concentration of 1-2%, stirring at a speed of 300-400r / min, stirring at 50-60℃ for 1-2h until the chitosan is completely dissolved to obtain a chitosan solution;

[0025] S4: Composite dispersion, adding nano-montmorillonite loaded with antimicrobial peptide, polyvinyl alcohol and silane coupling agent to the chitosan solution, dispersing for 30-40min at a power of 300-400W using ultrasonic dispersion equipment, controlling the temperature at 40-50℃ during the process to avoid excessive temperature leading to inactivation of the antimicrobial peptide;

[0026] S5: Coating and drying, coating the dispersed antimicrobial slurry on the surface of the substrate layer, placing it in a forced air drying oven after coating, drying at 80-90℃ for 1-2h, controlling the air speed at 1-2m / s during the drying process to ensure uniform drying of the antimicrobial layer, forming an antimicrobial layer with a thickness of 5-10μm.

[0027] Further, the preparation of the substrate layer includes the following steps:

[0028] S1: Raw material pretreatment, drying the modified polylactic acid and polybutylene adipate at 80-90℃ for 2-3h to remove moisture to avoid air bubbles in subsequent processing;

[0029] S2: Raw material mixing, adding the dried modified polylactic acid, polybutylene adipate, nano-titanium dioxide and tributyl citrate according to the proportion into a high-speed mixer, mixing at a speed of 800-1000r / min for 15-20min, controlling the temperature at 50-60℃ during the mixing process to improve the mixing uniformity;

[0030] S3: extrusion granulation, the mixture is added to a twin-screw extruder, the screw zone 1 temperature is set to 160-165°C, the screw zone 2 temperature is set to 165-170°C, the screw zone 3 temperature is set to 170-175°C, the die head temperature is set to 175-180°C, the screw rotation speed is set to 300-400 r / min, and after extrusion, the granulator is used to cut the base material master batch into particles with a particle size of 2-3 mm;

[0031] S4: calendaring film forming, the base material master batch is added to the hopper of a calender, the calender roll temperature is controlled to be 150-160°C, the calendaring speed is controlled to be 1-2 m / min, the film thickness is controlled to be 20-30 μm by adjusting the calender roll spacing, and a base material film is obtained;

[0032] S5: surface treatment, the surface of the base material film is treated by using a plasma treatment device, the treatment power is 200-300 W, the treatment time is 5-10 s, the roughness and adhesion of the surface of the base material film are improved, and the subsequent antibacterial layer coating is facilitated;

[0033] S6: cooling and shaping, the base material film after surface treatment is cooled by a cooling roll, the cooling roll temperature is 20-30°C, the pulling speed is consistent with the calendaring speed, and after cooling, the base material layer is obtained.

[0034] Further, the preparation of the leakage-proof layer comprises the following steps:

[0035] S1: preparation of modified silicon dioxide, nano-silicon dioxide is added to a γ-aminopropyl triethoxysilane ethanol solution with a mass concentration of 5-8%, the solid-liquid ratio is 1:15-1:20, stirring is performed at 70-80°C for 3-4 h, then filtration is performed, and drying is performed at 110-120°C for 5-6 h to obtain modified silicon dioxide;

[0036] S2: raw material mixing, ethylene-vinyl acetate copolymer and modified silicon dioxide are added to a high-speed mixer according to the proportion, mixing is performed at a rotation speed of 600-800 r / min for 10-15 min, and the mixing temperature is controlled to be 60-70°C to obtain a leakage-proof mixture;

[0037] S3: melt extrusion, the leakage-proof mixture is added to a single-screw extruder, the screw zone 1 temperature is set to 150-155°C, the screw zone 2 temperature is set to 155-160°C, the screw zone 3 temperature is set to 160-165°C, the die head temperature is set to 165-170°C, and the screw rotation speed is set to 200-300 r / min to extrude a film blank;

[0038] S4: film forming, the film blank is pulled to a shaping roll by a pulling machine, the shaping roll temperature is 80-90°C, the pulling speed is 1.5-2.5 m / min, and the film blank is pressed into a leakage-proof layer preliminary product with a thickness of 15-25 μm by the shaping roll;

[0039] S5: surface treatment, corona treatment is performed on one side surface of the initial product of the leak-proof layer, the treatment intensity is 30-40 dyn / cm, the treatment time is 3-5 s, the composite adhesion of the leak-proof layer and the antibacterial layer is improved, and then rolling is performed to obtain the leak-proof layer.

[0040] Further, the improved method of micro-hole processing comprises the following steps:

[0041] S1: positioning mark, printing a positioning mark on the surface of the composite film after the leak-proof layer is compounded by using a flexible printing device, the mark is circular, the diameter is 0.2-0.3 mm, the mark spacing is consistent with the preset micro-hole spacing, and the mark spacing and the preset micro-hole spacing are both 0.5-1 mm;

[0042] S2: laser drilling, the composite film is fixed on a drilling workbench, the workbench is used for fixing the composite film in a vacuum adsorption mode, the laser drilling equipment is accurately positioned according to the positioning mark, the laser power is set to 50-80 W, the drilling frequency is 50-100 Hz, and the laser action time is controlled to 10-20 μs during drilling to avoid damaging the antibacterial layer and the substrate layer below;

[0043] S3: dust removal treatment, a negative pressure suction equipment is used for removing dust on the surface of the composite film after drilling, the suction pressure is-0.05 to-0.08 MPa, the distance between the suction nozzle and the surface of the composite film is 5-10 mm, and the debris generated during drilling is removed;

[0044] S4: aperture detection, the composite film after dust removal is sent to an optical detection station, the micro-hole aperture is detected one by one through an optical microscope, the detection accuracy is set to 0.1 μm, the products with an aperture not meeting the requirement of 5-10 μm are selected for rework;

[0045] S5: surface smoothing treatment, the composite film after detection is qualified and is subjected to surface treatment through a polishing roller, the polishing roller temperature is 50-60 DEG C, the polishing speed is 0.5-1 m / min, the polishing roller surface is covered with wool felt, the micro-hole edge is smooth without burrs, and the sanitary napkin or skin is prevented from being scratched during use;

[0046] S6: rolling storage, the composite film after surface smoothing treatment is rolled, the rolling tension is controlled to 50-100 N, the composite film is stored in a dry environment after rolling, the environmental humidity is controlled to 30-50%, and the composite film is prevented from being affected by moisture to affect subsequent processing.

[0047] The beneficial effects of the application are as follows:

[0048] Long-acting synergistic antibacterial effect: the existing single chemical bacteriostatic agent or basic antibacterial component has short antibacterial time and is prone to microbial drug resistance. The application combines the ultraviolet sterilization process with the "antibacterial peptide-loaded nanometer montmorillonite + chitosan + loofah fiber" composite system, and the antibacterial rate of Escherichia coli and Staphylococcus aureus is more than 99% in 24 hours, the antibacterial effect lasts more than 6 months, and the long-acting synergistic antibacterial ability of the prior art is solved.

[0049] High-efficiency environmental-friendly degradation effect: the existing substrate layer is mostly ordinary degradable resin, and the degradation rate is generally less than 70% in 83 days. The application adds a composite degradation promoter to the substrate layer, and the soil burial degradation rate is more than 88% in 83 days, and there is no toxic residue in the degradation process, solving the problems of slow degradation rate and large environmental burden of the prior art, and meeting the current environmental protection packaging requirements.

[0050] Balanced effect of air permeability and leakage prevention: the existing technology only emphasizes the leakage prevention barrier property, resulting in insufficient air permeability, or unreasonable air permeability design causing liquid leakage risk. The leakage prevention layer of the application is provided with 5-10 mu air permeable micropores, and the oxygen permeability is 4.5-5.2 cm 3 / (m 2 24h 0.1MPa), which not only avoids the moisture deterioration of the inside of the packaging bag, but also ensures the leakage prevention performance (leakage time > 10 min), and realizes the precise balance of air permeability and leakage prevention. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the application are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the application, not all. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the application.

[0052] Embodiment description: embodiments 1-3 are prepared based on the technical solutions, and the raw material ratio and preparation parameters of the substrate layer, antibacterial layer and leakage prevention layer in each embodiment are within the protection scope, as follows:

[0053] Embodiment 1

[0054] Substrate layer: 60 parts by weight of modified polylactic acid, 20 parts by weight of polybutylene adipate, 3 parts by weight of nanometer titanium dioxide, 1 part by weight of tributyl citrate, and 0.8 parts by weight of degradation promoter (1 part by weight of polyethylene glycol, 0.3 parts by weight of organic acid, and 0.2 parts by weight of organic montmorillonite); extrusion granulation in a twin-screw extruder at 160 DEG C in the first zone, 165 DEG C in the second zone, 170 DEG C in the third zone, and 175 DEG C in the die head, with a screw rotation speed of 300 r / min, and calendering into a 20 mu thick substrate layer.

[0055] Antibacterial layer: 10 parts by weight of nano-montmorillonite loaded with antibacterial peptide, 5 parts by weight of chitosan, 2 parts by weight of polyvinyl alcohol, 0.5 parts by weight of silane coupling agent, and 1 part by weight of loofah fiber (pretreated with 5% sodium hydroxide solution for 2 h); ultrasonic dispersion power of 300 W for 30 min, coating thickness of 5 μm, and drying at 80 °C for 1 h to form the antibacterial layer.

[0056] Leakage-proof layer: 80 parts by weight of ethylene-vinyl acetate copolymer and 10 parts by weight of modified silica (20 nm, modified with γ-aminopropyl triethoxysilane); extruded into a 15 μm thick leakage-proof layer at a single screw extruder zone 1 of 150 °C, zone 2 of 155 °C, zone 3 of 160 °C, and die of 165 °C, screw rotation speed of 200 r / min, and then micro-holes with a pore size of 5 μm and a hole spacing of 0.5 mm were formed by a micro-hole processing method.

[0057] Composite and post-processing: three layers were hot-pressed at a temperature of 120 °C, a pressure of 0.3 MPa, and a time of 30 s, heat-sealed at a temperature of 130 °C, a time of 1 s, and a width of 2 mm, and sterilized by ultraviolet light (intensity of 200 μW / cm², time of 15 min), and the total thickness was 40 μm.

[0058] Example 2

[0059] Substrate layer: 70 parts by weight of modified polylactic acid, 25 parts by weight of polybutylene adipate, 4 parts by weight of nano-titanium dioxide, 1.5 parts by weight of tributyl citrate, and 1.2 parts by weight of a degradation promoter (1.5 parts by weight of polyethylene glycol, 0.4 parts by weight of an organic acid, and 0.3 parts by weight of organic montmorillonite); a double screw extruder zone 1 of 162 °C, zone 2 of 167 °C, zone 3 of 172 °C, and die of 177 °C, screw rotation speed of 350 r / min, and then extruded into a 25 μm thick substrate layer.

[0060] Antibacterial layer: 12 parts by weight of nano-montmorillonite loaded with antibacterial peptide, 6 parts by weight of chitosan, 3 parts by weight of polyvinyl alcohol, 0.8 parts by weight of silane coupling agent, and 2 parts by weight of loofah fiber (pretreated with 6% sodium hydroxide solution for 2.5 h); ultrasonic dispersion power of 350 W for 35 min, coating thickness of 8 μm, and drying at 85 °C for 1.5 h to form the antibacterial layer.

[0061] Leakage-proof layer: 85 parts by weight of ethylene-vinyl acetate copolymer and 15 parts by weight of modified silica (35 nm, modified with γ-aminopropyl triethoxysilane); a single screw extruder zone 1 of 152 °C, zone 2 of 157 °C, zone 3 of 162 °C, and die of 167 °C, screw rotation speed of 250 r / min, and then extruded into a 20 μm thick leakage-proof layer, and micro-holes with a pore size of 8 μm and a hole spacing of 0.8 mm were formed.

[0062] Composite and post-processing: hot-pressed at a temperature of 125 °C, a pressure of 0.4 MPa, and a time of 45 s, heat-sealed at a temperature of 135 °C, a time of 1.5 s, and a width of 2.5 mm, sterilized by ultraviolet light (intensity of 250 μW / cm², time of 18 min), and the total thickness was 52 μm.

[0063] Example 3

[0064] Substrate layer: 80 parts by weight of modified polylactic acid, 30 parts of polybutylene adipate, 5 parts of nano-titanium dioxide, 2 parts of tributyl citrate, 1.5 parts of degradation promoter (2 parts of polyethylene glycol, 0.5 parts of organic acid, and 0.4 parts of organic montmorillonite); the first zone of the twin-screw extruder was at 165°C, the second zone was at 170°C, the third zone was at 175°C, the die head was at 180°C, the screw rotation speed was 400 r / min, and the substrate layer was calendered to a thickness of 30 μm.

[0065] Antibacterial layer: 15 parts by weight of nano-montmorillonite loaded with antibacterial peptide, 8 parts of chitosan, 4 parts of polyvinyl alcohol, 1 part of silane coupling agent, and 3 parts of loofah fiber (pretreated with 8% sodium hydroxide solution for 3 h); the ultrasonic dispersion power was 400 W, the time was 40 min, the coating thickness was 10 μm, and the antibacterial layer was formed by drying at 90°C for 2 h.

[0066] Leakage-proof layer: 90 parts by weight of ethylene-vinyl acetate copolymer and 20 parts of modified silicon dioxide (50 nm, modified with γ-aminopropyl triethoxysilane); the first zone of the single-screw extruder was at 155°C, the second zone was at 160°C, the third zone was at 165°C, the die head was at 170°C, the screw rotation speed was 300 r / min, the leakage-proof layer was calendered to a thickness of 25 μm, and micropores with a pore size of 10 μm and a pore spacing of 1 mm were formed.

[0067] Compound and post-treatment: hot-pressing temperature of 130°C, pressure of 0.5 MPa, time of 60 s, heat-sealing temperature of 140°C, time of 2 s, width of 3 mm, ultraviolet sterilization (intensity of 300 μW / cm², time of 20 min), and total thickness of 65 μm.

[0068] Comparative example 1-3 were adjusted for the core technology (antibacterial layer component, leakage-proof layer micropore, and degradation promoter), as follows.

[0069] Comparative example 1

[0070] Different from example 1 (without nano-montmorillonite loaded with antibacterial peptide, single bacteriostatic agent): 10 parts of nano-montmorillonite loaded with antibacterial peptide were removed from the antibacterial layer and replaced with a bacteriostatic agent (a mixture of 1 part of 8-hydroxyquinolinone and 0.3 parts of tributyltin acetate), and the rest of the raw material ratio and preparation parameters were consistent with example 1.

[0071] Design purpose: to compare the antibacterial effect difference between the “nano-montmorillonite loaded with antibacterial peptide + chitosan + loofah fiber” composite antibacterial system and the single chemical bacteriostatic agent system.

[0072] Comparative example 2

[0073] Differences from Example 1 (leakage-proof layer without air-permeable micropores, barrier design idea): the leakage-proof layer does not undergo the micropore processing step, and there are no 5-10 μm air-permeable micropores. The remaining raw material ratio and preparation parameters are consistent with Example 1.

[0074] Design purpose: comparison of the air permeability and moisture resistance effect differences between the "leakage-proof layer + air-permeable micropore" structure of the application and the barrier design.

[0075] Comparative Example 3

[0076] Differences from Example 1 (substrate layer without degradation promoter, basic degradation component idea): 0.8 parts of the degradation promoter are removed from the substrate layer, and only the basic degradation components such as modified polylactic acid, polybutylene adipate, etc. are retained. The remaining raw material ratio and preparation parameters are consistent with Example 1.

[0077] Design purpose: comparison of the degradation rate differences between the "basic degradation component + degradation promoter" system of the application and the basic degradation component only.

[0078] Detection standard and method:

[0079] Antibacterial performance: according to the current standard GB / T31402-2023 "Determination of antibacterial activity on the surface of plastics and other non-porous materials", the 24h inhibition rate of Escherichia coli (ATCC25922) and Staphylococcus aureus (ATCC6538) is detected.

[0080] Air permeability: according to the current standard GB / T1038.1-2022 "Plastic products - Films and sheets - Determination of gas transmission - Part 1: Differential pressure method", the oxygen transmission rate (cm 3 / (m 2 24h 0.1MPa) is detected; according to GB / T1037-2021 "Determination of water vapor transmission performance of plastic films and sheets - Cup method for weight gain and weight loss", the water vapor transmission rate (g / (m 2 d) is detected.

[0081] Degradation performance: according to the current standard GB / T19277.1-2011 "Determination of ultimate aerobic biodegradability of materials under controlled composting conditions - Part 1: General method", the weight loss degradation rate (%) after 83 days of soil burial is detected.

[0082] Mechanical properties: according to the current standard GB / T1040.3-2006 "Determination of tensile properties of plastics - Part 3: Test conditions for films and sheets", the tensile strength (MPa) and elongation at break (%) are detected.

[0083] Leakage resistance: after 0.5 mL of physiological saline was added dropwise, whether leakage occurred within 10 min was observed, and the leakage time (min, no leakage was recorded as ">10") was recorded.

[0084] The detection results are shown in the following table:

[0085]

[0086] Result analysis:

[0087] Antibacterial performance: the antibacterial rates of examples 1-3 were all above 99%, which were significantly better than that of comparative example 1 (81%-83%), indicating that the antibacterial effect of the composite antibacterial system (nanometer montmorillonite loaded with antibacterial peptide + chitosan + loofah fiber) of the application was much better than that of a single chemical antibacterial agent system, and the antibacterial stability was stronger.

[0088] Breathability: the oxygen permeability of examples 1-3 was 4.5-5.2 cm 3 / (m 2 24h 0.1 MPa), and the water vapor permeability was 20.2-23.5 g / (m 2 d), which met the moderate barrier property required for storage of sanitary napkins, avoided the problem of insufficient permeability of comparative example 2 (no micropore, oxygen permeability 1.8 cm 3 / (m 2 24h 0.1 MPa), which could prevent the internal moisture of the packaging bag from causing the sanitary napkin to deteriorate, and was better than a design that only emphasized barrier property.

[0089] Degradation performance: the 83-day degradation rate of examples 1-3 was 88.6%-89.8%, which was significantly higher than that of comparative example 3 (75.2%), indicating that the degradation promoter of the application could effectively accelerate the degradation of the substrate layer, solve the problem of slow degradation rate of the basic degradation component, and be more in line with environmental protection requirements.

[0090] Mechanical and leakage resistance: the tensile strength of examples 1-3 was 20.5-22.1 MPa, and the elongation at break was 350%-380%, which were all better than those of comparative example 1 (tensile strength 18.2 MPa, elongation at break 320%), and all the samples had no leakage, indicating that the application improved the mechanical stability by optimizing the raw material ratio while ensuring the leakage resistance, which met the strength requirement of the packaging bag.

[0091] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely exemplary of the principles and application of the present application. Numerous modifications and adaptions can be effected without departing from the spirit and scope of the present application, which is not limited to the exact construction and arrangement described. It is intended, therefore, to cover all modifications and adaptions that fall within the scope of the claims and their equivalents.

Claims

1. An antibacterial sanitary napkin packaging bag characterized by comprising: The application relates to a composite material for a medical dressing, which comprises a substrate layer, an antibacterial layer and a leakage-proof layer which are sequentially compounded; the substrate layer is prepared by blending 60-80 parts by weight of modified polylactic acid, 20-30 parts by weight of polybutylene adipate, 3-5 parts by weight of nano-titanium dioxide, 0.8-1.5 parts by weight of a degradation promoter and 1-2 parts by weight of tributyl citrate; the antibacterial layer is prepared by compounding 10-15 parts by weight of nano-montmorillonite loaded with antibacterial peptides, 5-8 parts by weight of chitosan, 2-4 parts by weight of polyvinyl alcohol, 1-3 parts by weight of loofah fiber and 0.5-1 part by weight of a silane coupling agent; and the leakage-proof layer is prepared by blending 80-90 parts by weight of ethylene-vinyl acetate copolymer and 10-20 parts by weight of modified silicon dioxide, and the surface of the leakage-proof layer is provided with uniformly distributed air-permeable micropores. The loofah fiber is pretreated with a 5-8% sodium hydroxide solution for 2-3 hours, and then mixed with the nano-montmorillonite loaded with antibacterial peptides and chitosan. The modified silicon dioxide in the leakage-proof layer is nano-silicon dioxide modified by gamma-aminopropyl triethoxysilane, and the particle size of the modified silicon dioxide is 20-50 nm. The degradation promoter is prepared by mixing 1-2 parts by weight of polyethylene glycol, 0.3-0.5 parts by weight of an organic acid and 0.2-0.4 parts by weight of organic montmorillonite. The preparation of the antibacterial layer comprises the following steps: S1: nano-montmorillonite modification, the nano-montmorillonite is added into a 10-15% hydrochloric acid solution, the solid-liquid ratio is 1:10-1:15, stirring is carried out at 60-70 DEG C for 2-3 hours, then the nano-montmorillonite is filtered and washed until neutral, and the acidified nano-montmorillonite is obtained by drying at 100-110 DEG C for 4-5 hours; S2: antibacterial peptide loading, the antibacterial peptide is dissolved into a 0.5-1% aqueous solution, the acidified nano-montmorillonite is added, the solid-liquid ratio is 1:20-1:30, stirring is carried out at 30-40 DEG C for 4-5 hours, then centrifugation is carried out, and the nano-montmorillonite loaded with antibacterial peptides is obtained by drying at 80-90 DEG C for 3-4 hours; S3: compounding and dispersing, the nano-montmorillonite loaded with antibacterial peptides, polyvinyl alcohol, loofah fiber and silane coupling agent are added into a chitosan solution, and the antibacterial slurry is prepared by ultrasonic dispersion at 300-400 W for 30-40 minutes; S4: coating and drying, the antibacterial slurry is coated on the surface of the substrate layer, and drying is carried out at 80-90 DEG C for 1-2 hours, so that the antibacterial layer with a thickness of 5-10 microns is formed; The preparation of the substrate layer comprises the following steps: S1: raw material pretreatment, the modified polylactic acid and the polybutylene adipate are dried at 80-90 DEG C for 2-3 hours; S2: raw material mixing, the dried modified polylactic acid, polybutylene adipate, nano-titanium dioxide, tributyl citrate and degradation promoter are added into a high-speed mixer according to the proportion, and mixing is carried out at 800-1000 r / min for 15-20 minutes; S3: extrusion granulation, the mixture is extruded and granulated by a double-screw extruder, and the substrate master batch with a particle size of 2-3 mm is prepared; S4: calendering and surface treatment, the substrate master batch is calendered into a 20-30 micron thick film by a calendering machine, the surface is treated by plasma at 200-300 W for 5-10 seconds, and the substrate layer is obtained after cooling and setting; The preparation of the leakage-proof layer comprises the following steps: S1: Preparation of modified silica, nano-silica was added to 5-8% γ-aminopropyl triethoxysilane ethanol solution, solid-liquid ratio 1:15-1:20, stirring at 70-80℃ for 3-4h, then filtered, dried at 110-120℃ for 5-6h; S2: Mixing of raw materials, ethylene-vinyl acetate copolymer and modified silica were added into a high-speed mixer according to the ratio, mixed at 600-800r / min for 10-15min; S3: Melt forming, the mixed material was extruded into a film by a single screw extruder, and was drawn into a 15-25μm thick film, then was treated by corona at 30-40dyn / cm for 3-5s to obtain the leakage-proof layer; The improved method for micro-hole processing includes the following steps: S1: Positioning mark, printing circular marks with a diameter of 0.2-0.3mm on the surface of the composite film; S2: Laser drilling, drilling a gas-permeable micro-hole with a pore size of 5-10μm by using a 50-80W laser according to the positioning mark; S3: Post-processing, after drilling, dust removal under negative pressure of-0.05 to-0.08MPa, optical detection of pore size, 50-60℃ polishing roller treatment, winding tension control of 50-100N.

2. The antibacterial sanitary napkin packaging bag according to claim 1, wherein The thickness of the antibacterial layer is 5-10μm, the thickness of the substrate layer is 20-30μm, the thickness of the leakage-proof layer is 15-25μm, and the total thickness of the three-layer composite is 40-65μm.

3. A method for producing an antibacterial sanitary napkin packaging bag, for producing the antibacterial sanitary napkin packaging bag according to any one of claims 1 to 2, characterized by, The method includes the following steps: S1: Preparation of substrate layer, modified polylactic acid, polybutylene adipate, nano-titanium dioxide, tributyl citrate and degradation promoter were added into a high-speed mixer according to the ratio, mixed at a speed of 800-1000r / min for 15-20min, then the mixed material was added into a twin-screw extruder, the temperature of each zone of the screw was controlled at 160-165℃ for the first zone, 165-170℃ for the second zone, 170-175℃ for the third zone, and 175-180℃ for the die head, the screw speed was 300-400r / min, the mixed material was extruded and granulated, then was calendered into a film by a calender machine to obtain the substrate layer; S2: Antibacterial layer coating, nano-montmorillonite loaded with antibacterial peptide, chitosan, polyvinyl alcohol, luffa fiber and silane coupling agent were mixed according to the ratio, deionized water was added to adjust the solid content to 30-40%, and an antibacterial slurry was prepared, the antibacterial slurry was coated on one side surface of the substrate layer by using a doctor blade coating method, the coating thickness was controlled at 5-10μm, then dried at 80-90℃ for 1-2h to form the antibacterial layer; S3: Leakage-proof layer compounding, ethylene-vinyl acetate copolymer and modified silica were mixed according to the ratio, and were melt-extruded into a film at 150-170℃ to obtain the leakage-proof layer, the leakage-proof layer was aligned with the side surface of the antibacterial layer away from the substrate layer, and the two layers were compounded by a hot press compounding machine, the hot press temperature was controlled at 120-130℃, the pressure was 0.3-0.5MPa, and the compounding time was 30-60s; S4: Micro-hole processing, a laser drilling device was used to process gas-permeable micro-holes on the surface of the leakage-proof layer, the drilling speed was set at 100-150 holes / minute, the hole spacing was 0.5-1mm, and the micro-hole diameter was monitored by an optical sensor to ensure that the diameter was maintained at 5-10μm; S5: heat sealing forming, according to the size of the sanitary napkin, the composite film material is cut into a preset shape, the edges of the film material are heat sealed by using a heat sealing machine, the heat sealing temperature is controlled to be 130-140 DEG C, the heat sealing time is 1-2 s, and the heat sealing width is 2-3 mm; S6: sterilization treatment, the heat sealing formed packaging bag is placed into an ultraviolet sterilization box, the ultraviolet intensity is set to be 200-300 muW / cm2, the sterilization time is 15-20 min, after sterilization, natural cooling to room temperature is carried out, and an antibacterial sanitary napkin packaging bag is obtained.

Images