High-barrier puncture-resistant food packaging film and preparation method thereof
The high-barrier puncture-resistant food packaging film prepared by blending and blow molding of modified polystyrene, modified vermiculite sheets and zinc chloride solves the shortcomings of traditional packaging films in oxygen permeation, mechanical damage, microbial contamination and aging, and achieves efficient preservation and safety guarantees of food.
Patent Information
- Application Number
- CN202510240281.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-03
- Publication Date
- 2025-05-23
AI Technical Summary
The existing food packaging film is susceptible to multiple challenges such as oxygen penetration, mechanical damage, microbial contamination and aging during storage, transportation and sales, and is difficult to meet the high standards of the modern food industry.
Modified polystyrene, modified vermiculite sheets and zinc chloride were melt-blended and then prepared into a film through a blow molding mechanism, and reacted with iodine and aluminum powder to produce a high barrier puncture-resistant food packaging film.
The packaging film has good high barrier properties, puncture resistance, antibacterial properties and anti-aging properties, which can effectively extend the shelf life of food and ensure the safety and quality of food.
Smart Images
Figure BDA0005293902630000121
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of food packaging films, in particular to a high-barrier and puncture-resistant food packaging film and a preparation method thereof. Background Art
[0002] With the rapid development of the modern food industry and the increasing requirements of consumers for food safety, quality and freshness, the functional requirements of food packaging films are becoming increasingly diversified and refined. Food packaging films are not only the external protective layer of food, but also an important barrier to extend the shelf life of food, maintain food quality and ensure food safety. However, traditional single-material packaging films, such as polyethylene, polypropylene, polystyrene, etc., have been unable to meet the high standards of modern food packaging due to their performance limitations.
[0003] First, during the storage and circulation of food, it is easy to be affected by external factors such as oxygen and water vapor, which may lead to problems such as food oxidation, deterioration, and loss of nutrients. High barrier packaging film can effectively block the penetration of gases such as oxygen, water vapor, and carbon dioxide, thereby delaying the oxidation and deterioration of food and maintaining the color, aroma, and nutritional value of food. Secondly, during the transportation, storage, and sales of food, it is often exposed to external mechanical forces, such as puncture or extrusion by sharp objects. If the puncture resistance of the packaging film is insufficient, it is easy to cause damage to the packaging, which in turn causes food contamination or deterioration.
[0004] In addition, the reproduction of microorganisms such as bacteria and molds will not only destroy the quality of food, but also produce harmful substances, threatening the health of consumers. Therefore, it is of great significance to give food packaging films antibacterial properties; finally, during storage and use, food packaging films are often exposed to light, heat and oxygen environments, which will accelerate the aging and degradation of the packaging films, resulting in a decrease in their mechanical properties and barrier properties.
[0005] In summary, since food faces multiple challenges such as oxygen permeation, mechanical damage, microbial contamination, and aging during storage, transportation, and sales, developing a multifunctional food packaging film with high barrier properties, puncture resistance, antibacterial properties, and anti-aging properties has become the key to solving these problems. This packaging film can not only effectively extend the shelf life of food, but also ensure the safety and quality of food, meeting the development of the modern food industry and consumers' demand for high-quality life. Summary of the invention
[0006] The object of the present invention is to provide a high-barrier and puncture-resistant food packaging film and a preparation method thereof, so as to solve the problems existing in the prior art.
[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:
[0008] A high-barrier and puncture-resistant food packaging film is prepared by melt-blending modified polystyrene, modified vermiculite flakes and zinc chloride, preparing the film by a blow molding machine, and then reacting with iodine and aluminum powder.
[0009] As an optimization, the modified polystyrene is obtained by grafting 2-vinylhexafluoroisopropanol onto polystyrene, then reacting with 2-chloro-2-oxy-1,3,2-dioxaphospholane, and then reacting with 4-(dimethylamino)-2-methoxybenzonitrile.
[0010] As an optimization, the modified vermiculite flakes are obtained by reacting pretreated vermiculite flakes with hydrogen-containing silicone oil and 1-(5-vinyl-2-hydroxyphenyl)ethanone, then with phosphorus oxychloride and N,N-dimethylformamide, and then with hydroxylamine hydrochloride and sodium iodide.
[0011] A method for preparing a high-barrier and puncture-resistant food packaging film comprises the following preparation steps:
[0012] (1) mixing polystyrene, benzoyl peroxide, 2-vinylhexafluoroisopropanol, and dimethyl sulfoxide to obtain hydroxylated polystyrene;
[0013] (2) mixing hydroxylated polystyrene, triethylamine and tetrahydrofuran, and adding dropwise 2-chloro-2-oxy-1,3,2-dioxaphospholane solution to react to obtain a modified polystyrene precursor; mixing the modified polystyrene precursor, 4-(dimethylamino)-2-methoxybenzonitrile and tetrahydrofuran to react to obtain a modified polystyrene;
[0014] (3) mixing pretreated vermiculite flakes, hydrogenated silicone oil, 1-(5-vinyl-2-hydroxyphenyl)ethanone, Custer catalyst, and dichloromethane to obtain silicone oil-modified vermiculite flakes; mixing phosphorus oxychloride and N,N-dimethylformamide, adding silicone oil-modified vermiculite flakes and N,N-dimethylformamide to react to obtain pre-modified vermiculite flakes;
[0015] (4) Pre-modified vermiculite flakes, hydroxylamine hydrochloride, sodium iodide, and acetonitrile are mixed, heated to 80° C. for reaction for 2 h, and after the reaction is completed, filtered and washed with pure water for 3-4 times, and dried at room temperature to obtain modified vermiculite flakes;
[0016] (5) Mixing modified polystyrene, modified vermiculite flakes and zinc chloride in a mass ratio of 1:(0.03-0.05):0.01 in a high-speed mixer at a speed of 1000 r / min for 10 min, taking out and mixing in an open mill for 5 min, with the temperature of the front roller and the rear roller of the open mill being 120° C.; then extruding and granulating by a twin-screw extruder, and preparing a film by a blow molding machine to obtain a polystyrene composite film;
[0017] (6) Iodine, aluminum powder, and acetonitrile are mixed, heated to 85° C., refluxed and stirred for 3 h, cooled to room temperature, added with a polystyrene composite film, heated to 85° C., reacted for 3-4 h, and after the reaction, taken out and washed with pure water for 3-4 times, and vacuum dried at 50° C. to obtain a high barrier and puncture-resistant food packaging film.
[0018] As an optimization, the preparation method of the hydroxylated polystyrene in step (1) is: polystyrene, benzoyl peroxide, 2-vinylhexafluoroisopropanol, and dimethyl sulfoxide are mixed in a mass ratio of 1: (0.002-0.003): (0.1-0.2): (20-30), and under nitrogen protection, the temperature is raised to 90° C. for reaction for 1 hour, and the temperature is raised to 130-140° C. for reaction for 1 hour. After the reaction, methanol 3-4 times the mass of dimethyl sulfoxide is added for precipitation, and the mixture is filtered and washed with methanol for 3-4 times. After vacuum drying at 50° C. for 24 hours, hydroxylated polystyrene is obtained; the polystyrene model is GPPS-251.
[0019] As an optimization, the preparation method of the modified polystyrene in step (2) is as follows: 2-chloro-2-oxy-1,3,2-dioxaphospholane and tetrahydrofuran are mixed in a mass ratio of 1:10 to obtain a 2-chloro-2-oxy-1,3,2-dioxaphospholane solution, hydroxylated polystyrene, triethylamine, tetrahydrofuran, and 2-chloro-2-oxy-1,3,2-dioxaphospholane solution are weighed in a mass ratio of 1:(0.2-0.3):(20-30):2, hydroxylated polystyrene, triethylamine, and tetrahydrofuran are mixed, cooled to -15°C, 2-chloro-2-oxy-1,3,2-dioxaphospholane solution is added dropwise, and the dropwise addition is accelerated. The stirring speed is 1 mL / min. After the addition is completed, stirring is continued for 2 h, and then the temperature is raised to room temperature and stirred for 2 h. After removing tetrahydrofuran by vacuum rotary evaporation, the mixture is washed with ether for 3-4 times to obtain a modified polystyrene precursor. Under sealed conditions, the modified polystyrene precursor, 4-(dimethylamino)-2-methoxybenzonitrile and tetrahydrofuran are mixed in a mass ratio of 1:(0.2-0.3):(20-30), the temperature is raised to 60°C and the reaction is carried out for 30-40 h. After the reaction is completed, methanol in an amount of 60-70 times the mass of the modified polystyrene precursor is added for precipitation. The mixture is filtered and washed with pure water for 3-4 times, and dried at room temperature for 24 h to obtain a modified polystyrene.
[0020] As an optimization, the preparation method of the pretreated vermiculite flakes in step (3) is as follows: drying the expanded vermiculite at 80°C for 6h, placing it in a planetary ball mill for grinding, and the ball mill speed is 600r / min; the diameters of the grinding balls are 5mm, 10mm and 20mm, and the number ratio is 4:2:1; the filling amount of the expanded vermiculite is 1 / 3 of the volume of the ball mill, and the ball milling time is 15min to obtain layered vermiculite flakes; ethanol, pure water and vinyltrimethoxysilane are mixed in a mass ratio of 1:0.5:0.2, reacted at 40°C for 1h, adding 0.75 times the mass of ethanol to the layered vermiculite flakes, stirring at 60°C for 3h, standing at room temperature for 10h, filtering and washing with pure water for 3-4 times, and drying at 100°C for 4-6h to obtain pretreated vermiculite flakes; the expanded vermiculite particle size is 1-3mm.
[0021] As an optimization, the preparation method of the pre-modified vermiculite flakes in step (3) is as follows: pre-treated vermiculite flakes, hydrogenated silicone oil, 1-(5-vinyl-2-hydroxyphenyl) ethyl ketone, Custer catalyst, and dichloromethane are mixed in a mass ratio of 1:(0.2-0.3):(0.1-0.2):0.001:(20-30), heated to 80°C for reaction for 4-6 hours, filtered and washed with pure water for 3-4 times after the reaction, and dried at 100°C for 4-6 hours to obtain silicone oil-modified vermiculite flakes; phosphorus oxychloride, N, N-dimethylformamide is mixed at a mass ratio of 1:2 for 30 minutes, and silicone oil-modified vermiculite flakes with a mass of 5-6 times that of phosphorus oxychloride and N,N-dimethylformamide with a mass of 3 times that of phosphorus oxychloride are added and stirred for 5-6 minutes. The temperature is raised to room temperature and the reaction is continued for 4-6 hours. After the reaction is completed, the mixture is poured into an ice-water mixture, filtered and washed with pure water for 3-4 times, and dried at room temperature to obtain pre-modified vermiculite flakes; the hydrogen-containing silicone oil model is SI-H202; the Castel catalyst is platinum (0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane.
[0022] As an optimization, the mass ratio of the pre-modified vermiculite flakes, hydroxylamine hydrochloride, sodium iodide and acetonitrile in step (4) is 1:(0.02-0.03):(0.01-0.02):(20-30).
[0023] As an optimization, the twin-screw extruder parameters in step (5) are as follows: the temperatures of the first, second, third and fourth zones are 195°C, 205°C, 230°C and 235°C, and the head temperature is 230°C; the blow molding machine parameters are as follows: the screw speed of the blow molding machine is 650r / min, the temperatures of the first and second zones of the mold are both 155°C, and the temperatures of the barrel zones 1, 2 and 3 are 140°C, 150°C and 155°C, respectively.
[0024] As an optimization, the mass ratio of the polystyrene composite film, acetonitrile, iodine and aluminum powder in step (6) is: 1:(10-12):(0.7-0.8):(0.1-0.2); the particle size of the aluminum powder is 200 mesh.
[0025] Compared with the prior art, the beneficial effects achieved by the present invention are:
[0026] When preparing the high-barrier and puncture-resistant food packaging film, the present invention comprises the following steps: firstly, after being grafted with 2-vinylhexafluoroisopropanol, polystyrene is reacted with 2-chloro-2-oxy-1,3,2-dioxaphospholane, and then with 4-(dimethylamino)-2-methoxybenzonitrile to obtain modified polystyrene; secondly, after being reacted with pretreated vermiculite flakes, hydrogen-containing silicone oil and 1-(5-vinyl-2-hydroxyphenyl)ethanone, phosphorus oxychloride and N,N-dimethylformamide are reacted, and then with hydroxylamine hydrochloride and sodium iodide to obtain modified vermiculite flakes; finally, after the modified polystyrene, the modified vermiculite flakes and zinc chloride are melt-blended, a film is prepared by a blow molding machine, and then the film is reacted with iodine and aluminum powder to obtain the high-barrier and puncture-resistant food packaging film.
[0027] First, in the presence of initiator benzoyl peroxide, the grafting of polystyrene and 2-vinyl hexafluoroisopropanol is initiated by free radicals. The fluorine element with low surface energy can effectively block the penetration of some gases and water vapor. The grafting of 2-vinyl hexafluoroisopropanol can also introduce hydroxyl groups into the side chains of polystyrene. The hydroxyl groups react with 2-chloro-2-oxy-1,3,2-dioxaphospholane, and then react with 4-(dimethylamino)-2-methoxybenzonitrile to form a phosphorylcholine structure with antibacterial properties, and introduce 4-(dimethylamino)-2-methoxybenzonitrile.
[0028] Secondly, the expanded vermiculite is mechanically peeled into layered vermiculite flakes with good barrier properties. Flake fillers are added to the material to extend the diffusion path of gas molecules in the material, thereby improving the gas barrier properties of the material. Vinyltrimethoxysilane is used to modify the vermiculite flakes so that the surface of the vermiculite flakes contains double bonds. Hydrogenated silicon addition reaction is used to modify the surface of the vermiculite flakes with hydrophobic hydrogenated silicone oil and 1-(5-vinyl-2-hydroxyphenyl)ethanone. 1-(5-vinyl-2-hydroxyphenyl)ethanone and phosphorus oxychloride and N,N-dimethylformamide undergo a Vilsmeier-Hacke formylation reaction to generate a flavonoid structure containing an aldehyde group. The flavonoid structure has the ability to scavenge free radicals and can resist aging. The aldehyde group is then converted into a cyano group to obtain a modified vermiculite flake.
[0029] Finally, the modified polystyrene, modified vermiculite flakes, and zinc chloride are melt-blended and then formed into a film by a blow molding machine. Under high-temperature conditions and through the action of the catalyst zinc chloride, the cyano groups on the modified polystyrene and modified vermiculite flakes polymerize to form triazine groups. The modified polystyrene can also self-crosslink to form triazine groups, enhancing the crosslinking density within the material. While improving the mechanical properties of the material, it also improves the barrier property. Vermiculite is an inorganic rigid material with a relatively high elastic modulus. At the same time, the crosslinking formed between the vermiculite and the polystyrene molecular chains plays a role in evenly dispersing the load, thereby improving the puncture resistance. Under the action of aluminum iodide, the polystyrene composite film removes the methyl group on the side chain 4-(dimethylamino)-2-methoxybenzonitrile of polystyrene to form a phenolic hydroxyl group. The phenolic hydroxyl group and the nitrogen element on the adjacent triazine ring form an intramolecular chelation ring, which can convert light energy into heat energy to achieve the performance of anti-ultraviolet aging. Detailed implementation manners
[0030] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.
[0031] In the following examples and comparative examples, the polystyrene model used is GPPS-251, purchased from Shanghai Secco Petrochemical Co., Ltd.; the hydrogen-containing silicone oil model used is SI-H202, purchased from Laiyang Shengbang Organosilicon Technology Co., Ltd.; the Karstedt catalyst is platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane; the expanded vermiculite particle size is 1-3 mm, purchased from Xinjiang Weili Xinlong Vermiculite Co., Ltd.; the aluminum powder particle size is 200 mesh.
[0032] Example 1:
[0033] A preparation method of a high-barrier and puncture-resistant food packaging film, the preparation method of the high-barrier and puncture-resistant food packaging film includes the following preparation steps:
[0034] (1) Mix polystyrene, benzoyl peroxide, 2-vinylhexafluoroisopropanol, and dimethyl sulfoxide in a mass ratio of 1:0.002:0.1:20. Under nitrogen protection, heat up to 90 °C and react for 1 h, then heat up to 140 °C and react for 1 h. After the reaction is completed, add methanol three times the mass of dimethyl sulfoxide for precipitation, filter by suction and wash with methanol 4 times, and vacuum dry at 50 °C for 24 h to obtain hydroxylated polystyrene;
[0035] (2) 2-chloro-2-oxy-1,3,2-dioxaphospholane and tetrahydrofuran were mixed at a mass ratio of 1:10 to obtain a 2-chloro-2-oxy-1,3,2-dioxaphospholane solution; hydroxylated polystyrene, triethylamine, tetrahydrofuran, and 2-chloro-2-oxy-1,3,2-dioxaphospholane solution were weighed at a mass ratio of 1:0.2:20:2; hydroxylated polystyrene, triethylamine, and tetrahydrofuran were mixed, cooled to -15°C, and the 2-chloro-2-oxy-1,3,2-dioxaphospholane solution was added dropwise at a dropping rate of 1 mL / min. min, after the addition is completed, stirring is continued for 2h, and then the temperature is raised to room temperature and stirred for 2h, and tetrahydrofuran is removed by vacuum rotary evaporation and then washed with ether 4 times to obtain a modified polystyrene precursor; under sealed conditions, the modified polystyrene precursor, 4-(dimethylamino)-2-methoxybenzonitrile, and tetrahydrofuran are mixed in a mass ratio of 1:0.2:20, and the temperature is raised to 60°C for reaction for 40h. After the reaction is completed, methanol 70 times the mass of the modified polystyrene precursor is added for precipitation, filtered, washed with pure water 4 times, and dried at room temperature for 24h to obtain modified polystyrene;
[0036] (3) After drying the expanded vermiculite at 80°C for 6 hours, the expanded vermiculite was placed in a planetary ball mill for grinding at a speed of 600 r / min; the diameters of the grinding balls were 5 mm, 10 mm and 20 mm, and the number ratio was 4:2:1; the amount of expanded vermiculite filled was 1 / 3 of the volume of the ball mill, and the ball milling time was 15 minutes to obtain layered vermiculite flakes; ethanol, pure water and vinyltrimethoxysilane were mixed in a mass ratio of 1:0.5:0.2, reacted at 40°C for 1 hour, 0.75 times the mass of ethanol layered vermiculite flakes were added, stirred at 60°C for 3 hours, and then allowed to stand at room temperature for 10 hours, filtered and washed with pure water for 4 times, and dried at 100°C for 6 hours to obtain pretreated vermiculite flakes; the pretreated vermiculite flakes, hydrogenated silicone oil, 1 -(5-vinyl-2-hydroxyphenyl)ethanone, Custer catalyst, and dichloromethane are mixed in a mass ratio of 1:0.2:0.1:0.001:20, heated to 80°C for reaction for 6 hours, filtered and washed with pure water 4 times after the reaction, and dried at 100°C for 6 hours to obtain silicone oil-modified vermiculite flakes; phosphorus oxychloride and N,N-dimethylformamide are mixed in a mass ratio of 1:2 for 30 minutes at 0°C under nitrogen protection, and silicone oil-modified vermiculite flakes 5 times the mass of phosphorus oxychloride and N,N-dimethylformamide 3 times the mass of phosphorus oxychloride are added and stirred for 6 minutes, heated to room temperature and continued to react for 6 hours, after the reaction is completed, poured into an ice-water mixture, filtered and washed with pure water 4 times, and dried at room temperature to obtain pre-modified vermiculite flakes;
[0037] (4) pre-modified vermiculite flakes, hydroxylamine hydrochloride, sodium iodide, and acetonitrile were mixed in a mass ratio of 1:0.02:0.01:20, heated to 80° C. for reaction for 2 h, filtered and washed with pure water 4 times after the reaction, and dried at room temperature to obtain modified vermiculite flakes;
[0038] (5) Modified polystyrene, modified vermiculite flakes and zinc chloride are mixed in a high-speed mixer at a mass ratio of 1:0.03:0.01 at a speed of 1000 r / min for 10 min, taken out and mixed in an open mill for 5 min, the temperature of the front roller and the rear roller of the open mill being 120°C; then extruded and granulated by a twin-screw extruder, and prepared into a film by a blow molding machine to obtain a polystyrene composite film; the parameters of the twin-screw extruder are as follows: the temperatures of the first, second, third and fourth zones are 195°C, 205°C, 230°C and 235°C, and the head temperature is 230°C; the parameters of the blow molding machine are as follows: the screw speed of the blow molding machine is 650 r / min, the temperatures of the first and second zones of the mold are both 155°C, and the temperatures of the barrel zones 1, 2 and 3 are 140°C, 150°C and 155°C, respectively.
[0039] (6) Weigh a polystyrene composite film, acetonitrile, iodine, and aluminum powder in a mass ratio of 1:10:0.7:0.1, mix the iodine, aluminum powder, and acetonitrile, heat to 85°C, reflux with stirring for 3 h, cool to room temperature, add the polystyrene composite film, heat to 85°C, reflux with stirring for 4 h, and after the reaction is completed, take out and wash with pure water 4 times, and vacuum dry at 50°C to obtain a high barrier and puncture-resistant food packaging film.
[0040] Embodiment 2:
[0041] A method for preparing a high-barrier and puncture-resistant food packaging film, the method comprising the following preparation steps:
[0042] (1) polystyrene, benzoyl peroxide, 2-vinylhexafluoroisopropanol, and dimethyl sulfoxide were mixed in a mass ratio of 1:0.002:0.15:25, heated to 90°C for reaction for 1 hour, and then heated to 135°C for reaction for 1 hour under nitrogen protection. After the reaction, methanol 3.5 times the mass of dimethyl sulfoxide was added for precipitation, filtered and washed with methanol 3 times, and vacuum dried at 50°C for 24 hours to obtain hydroxylated polystyrene;
[0043] (2) 2-chloro-2-oxy-1,3,2-dioxaphospholane and tetrahydrofuran were mixed at a mass ratio of 1:10 to obtain a 2-chloro-2-oxy-1,3,2-dioxaphospholane solution; hydroxylated polystyrene, triethylamine, tetrahydrofuran, and 2-chloro-2-oxy-1,3,2-dioxaphospholane solution were weighed at a mass ratio of 1:0.25:25:2; hydroxylated polystyrene, triethylamine, and tetrahydrofuran were mixed, cooled to -15°C, and the 2-chloro-2-oxy-1,3,2-dioxaphospholane solution was added dropwise at a dropping rate of 1 mL / min. min, after the addition is completed, stirring is continued for 2h, and then the temperature is raised to room temperature and stirred for 2h, and tetrahydrofuran is removed by vacuum rotary evaporation and then washed with ether three times to obtain a modified polystyrene precursor; under sealed conditions, the modified polystyrene precursor, 4-(dimethylamino)-2-methoxybenzonitrile, and tetrahydrofuran are mixed in a mass ratio of 1:0.25:25, and the temperature is raised to 60°C for reaction for 35h. After the reaction is completed, methanol 65 times the mass of the modified polystyrene precursor is added for precipitation, filtered, washed with pure water three times, and dried at room temperature for 24h to obtain modified polystyrene;
[0044] (3) After drying the expanded vermiculite at 80°C for 6 hours, the expanded vermiculite was placed in a planetary ball mill for grinding at a speed of 600 r / min; the diameters of the grinding balls were 5 mm, 10 mm and 20 mm, and the number ratio was 4:2:1; the amount of expanded vermiculite filled was 1 / 3 of the volume of the ball mill, and the ball milling time was 15 minutes to obtain layered vermiculite flakes; ethanol, pure water and vinyltrimethoxysilane were mixed in a mass ratio of 1:0.5:0.2, reacted at 40°C for 1 hour, 0.75 times the mass of ethanol layered vermiculite flakes were added, stirred at 60°C for 3 hours, and then allowed to stand at room temperature for 10 hours, filtered and washed with pure water for 3 times, and dried at 100°C for 5 hours to obtain pretreated vermiculite flakes; the pretreated vermiculite flakes, hydrogenated silicone oil, 1-( 5-vinyl-2-hydroxyphenyl) acetone, Custer catalyst, and dichloromethane are mixed in a mass ratio of 1:0.25:0.15:0.001:25, heated to 80°C for reaction for 5 hours, filtered and washed with pure water 3 times after the reaction, and dried at 100°C for 5 hours to obtain silicone oil-modified vermiculite flakes; phosphorus oxychloride and N,N-dimethylformamide are mixed in a mass ratio of 1:2 for 30 minutes at 0°C under nitrogen protection, 5.5 times the mass of phosphorus oxychloride and 3 times the mass of phosphorus oxychloride N,N-dimethylformamide are added and stirred for 5 minutes, heated to room temperature and continued to react for 5 hours, after the reaction is completed, poured into an ice-water mixture, filtered and washed with pure water 3 times, and dried at room temperature to obtain pre-modified vermiculite flakes;
[0045] (4) pre-modified vermiculite flakes, hydroxylamine hydrochloride, sodium iodide, and acetonitrile were mixed in a mass ratio of 1:0.025:0.015:25, heated to 80°C for reaction for 2 hours, filtered and washed with pure water three times after the reaction, and dried at room temperature to obtain modified vermiculite flakes;
[0046] (5) Modified polystyrene, modified vermiculite flakes and zinc chloride are mixed in a high-speed mixer at a mass ratio of 1:0.04:0.01 at a speed of 1000 r / min for 10 min, taken out and mixed in an open mill for 5 min, and the temperature of the front roller and the rear roller of the open mill is 120°C; then, a twin-screw extruder is used for extrusion granulation, and a film is prepared by a blow molding machine to obtain a polystyrene composite film; the parameters of the twin-screw extruder are as follows: the temperatures of the first, second, third and fourth zones are 195°C, 205°C, 230°C and 235°C, and the head temperature is 230°C; the parameters of the blow molding machine are as follows: the screw speed of the blow molding machine is 650 r / min, the temperatures of the first and second zones of the mold are both 155°C, and the temperatures of the barrel zones 1, 2 and 3 are 140°C, 150°C and 155°C, respectively.
[0047] (6) Weigh a polystyrene composite film, acetonitrile, iodine, and aluminum powder in a mass ratio of 1:11:0.75:0.15, mix the iodine, aluminum powder, and acetonitrile, heat to 85°C, reflux with stirring for 3 h, cool to room temperature, add the polystyrene composite film, heat to 85°C, reflux with stirring for 3.5 h, and after the reaction is completed, take out and wash with pure water three times, and vacuum dry at 50°C to obtain a high barrier and puncture-resistant food packaging film.
[0048] Embodiment 3:
[0049] A method for preparing a high-barrier and puncture-resistant food packaging film, the method comprising the following preparation steps:
[0050] (1) polystyrene, benzoyl peroxide, 2-vinylhexafluoroisopropanol, and dimethyl sulfoxide are mixed in a mass ratio of 1:0.003:0.2:30, and the mixture is heated to 90°C for reaction for 1 hour and then heated to 130°C for reaction for 1 hour under nitrogen protection. After the reaction, methanol with a mass of 4 times that of dimethyl sulfoxide is added for precipitation, and the mixture is filtered and washed with methanol for 3 times. After vacuum drying at 50°C for 24 hours, hydroxylated polystyrene is obtained;
[0051] (2) 2-chloro-2-oxy-1,3,2-dioxaphospholane and tetrahydrofuran were mixed at a mass ratio of 1:10 to obtain a 2-chloro-2-oxy-1,3,2-dioxaphospholane solution; hydroxylated polystyrene, triethylamine, tetrahydrofuran, and 2-chloro-2-oxy-1,3,2-dioxaphospholane solution were weighed at a mass ratio of 1:0.3:30:2; hydroxylated polystyrene, triethylamine, and tetrahydrofuran were mixed, cooled to -15°C, and the 2-chloro-2-oxy-1,3,2-dioxaphospholane solution was added dropwise at a dropping speed of 1 mL / m in, after the addition is completed, stirring is continued for 2 hours, and then the temperature is raised to room temperature and stirred for 2 hours. After the tetrahydrofuran is removed by vacuum rotary evaporation, it is washed with ether for 3-4 times to obtain a modified polystyrene precursor; under sealed conditions, the modified polystyrene precursor, 4-(dimethylamino)-2-methoxybenzonitrile, and tetrahydrofuran are mixed in a mass ratio of 1:0.3:30, and the temperature is raised to 60°C for reaction for 30 hours. After the reaction is completed, methanol 70 times the mass of the modified polystyrene precursor is added for precipitation, filtered, washed with pure water 3 times, and dried at room temperature for 24 hours to obtain modified polystyrene;
[0052] (3) After drying the expanded vermiculite at 80°C for 6 hours, the expanded vermiculite was placed in a planetary ball mill for grinding at a speed of 600 r / min; the diameters of the grinding balls were 5 mm, 10 mm and 20 mm, and the number ratio was 4:2:1; the amount of expanded vermiculite filled was 1 / 3 of the volume of the ball mill, and the ball milling time was 15 minutes to obtain layered vermiculite flakes; ethanol, pure water and vinyltrimethoxysilane were mixed in a mass ratio of 1:0.5:0.2, reacted at 40°C for 1 hour, 0.75 times the mass of ethanol layered vermiculite flakes were added, stirred at 60°C for 3 hours, and then allowed to stand at room temperature for 10 hours, filtered and washed with pure water for 3 times, and dried at 100°C for 4 hours to obtain pretreated vermiculite flakes. -(5-vinyl-2-hydroxyphenyl)ethanone, Custer catalyst, and dichloromethane are mixed in a mass ratio of 1:0.3:0.2:0.001:30, heated to 80°C for reaction for 4 hours, filtered and washed with pure water 3 times after the reaction, and dried at 100°C for 4 hours to obtain silicone oil-modified vermiculite flakes; phosphorus oxychloride and N,N-dimethylformamide are mixed in a mass ratio of 1:2 for 30 minutes at 0°C under nitrogen protection, and silicone oil-modified vermiculite flakes 6 times the mass of phosphorus oxychloride and N,N-dimethylformamide 3 times the mass of phosphorus oxychloride are added and stirred for 5 minutes, heated to room temperature and continued to react for 4 hours, after the reaction is completed, poured into an ice-water mixture, filtered and washed with pure water 3 times, and dried at room temperature to obtain pre-modified vermiculite flakes;
[0053] (4) pre-modified vermiculite flakes, hydroxylamine hydrochloride, sodium iodide, and acetonitrile were mixed in a mass ratio of 1:0.03:0.02:30, heated to 80°C for reaction for 2 hours, filtered and washed with pure water three times after the reaction, and dried at room temperature to obtain modified vermiculite flakes;
[0054] (5) Modified polystyrene, modified vermiculite flakes and zinc chloride are mixed in a high-speed mixer at a mass ratio of 1:0.05:0.01 at a speed of 1000 r / min for 10 min, and then taken out and mixed in an open mill for 5 min, with the temperature of the front roller and the rear roller of the open mill being 120° C.; then extruded and granulated by a twin-screw extruder, and prepared into a film by a blow molding machine to obtain a polystyrene composite film; the parameters of the twin-screw extruder are: the temperatures of the first, second, third and fourth zones are 195° C., 205° C., 230° C. and 235° C., and the head temperature is 230° C.; the parameters of the blow molding machine are: the screw speed of the blow molding machine is 650 r / min, the temperatures of the first and second zones of the mold are both 155° C., and the temperatures of the barrel zones 1, 2 and 3 are 140° C., 150° C. and 155° C., respectively;
[0055] (6) Weigh a polystyrene composite film, acetonitrile, iodine, and aluminum powder in a mass ratio of 1:12:0.8:0.2, mix the iodine, aluminum powder, and acetonitrile, heat to 85°C, reflux and stir for 3 h, cool to room temperature, add the polystyrene composite film, heat to 85°C and react for 3 h. After the reaction is completed, take out and wash with pure water 3 times, and vacuum dry at 50°C to obtain a high barrier and puncture-resistant food packaging film.
[0056] Comparative Example 1:
[0057] The preparation method of the high barrier and puncture-resistant food packaging film of Comparative Example 1 differs from that of Example 2 in that it does not contain steps (1) to (2), and step (5) is modified as follows: polystyrene, modified vermiculite flakes, and zinc chloride are mixed in a high-speed mixer at a mass ratio of 1:0.04:0.01 at a speed of 1000 r / min for 10 min, taken out and mixed in an open mill for 5 min, and the temperature of the front roller and the rear roller of the open mill is 120°C; then, a twin-screw extruder is used for extrusion granulation, and a film is prepared by a blow molding machine to obtain a polystyrene composite film; the parameters of the twin-screw extruder are as follows: the temperatures of the first, second, third, and fourth zones are 195°C, 205°C, 230°C, and 235°C, and the head temperature is 230°C; the parameters of the blow molding machine are as follows: the screw speed of the blow molding machine is 650 r / min, the temperatures of the first and second zones of the mold are both 155°C, and the temperatures of the barrel zones 1, 2, and 3 are 140°C, 150°C, and 155°C, respectively.
[0058] Comparative Example 2:
[0059] The preparation method of the high barrier and puncture-resistant food packaging film of Comparative Example 2 differs from that of Example 2 in that it does not contain steps (3) and (4), and step (5) is modified as follows: modified polystyrene, vermiculite flakes and zinc chloride are mixed in a high-speed mixer at a mass ratio of 1:0.04:0.01 at a speed of 1000 r / min for 10 min, taken out and mixed in an open mill for 5 min, and the temperature of the front roller and the rear roller of the open mill is 120°C; then, a twin-screw extruder is used for extrusion granulation, and a film is prepared by a blow molding machine to obtain a polystyrene composite film; the parameters of the twin-screw extruder are as follows: the temperatures of the first, second, third and fourth zones are 195°C, 205°C, 230°C and 235°C, and the head temperature is 230°C; the parameters of the blow molding machine are as follows: the screw speed of the blow molding machine is 650 r / min, the temperatures of the first and second zones of the mold are both 155°C, and the temperatures of the barrel zones 1, 2 and 3 are 140°C, 150°C and 155°C, respectively.
[0060] Comparative Example 3:
[0061] The preparation method of the high barrier and puncture-resistant food packaging film of Comparative Example 3 differs from that of Example 2 in that step (6) is not included, and step (5) is modified as follows: modified polystyrene, modified vermiculite flakes, and zinc chloride are mixed in a high-speed mixer at a mass ratio of 1:0.04:0.01 at a speed of 1000 r / min for 10 min, taken out and mixed in an open mill for 5 min, and the temperature of the front roller and the rear roller of the open mill is 120°C; then, a twin-screw extruder is used for extrusion granulation, and a high barrier and puncture-resistant food packaging film is prepared by a blow molding machine; the parameters of the twin-screw extruder are as follows: the temperatures of the first, second, third, and fourth zones are 195°C, 205°C, 230°C, and 235°C, and the head temperature is 230°C; the parameters of the blow molding machine are as follows: the screw speed of the blow molding machine is 650 r / min, the temperatures of the first and second zones of the mold are both 155°C, and the temperatures of the barrel zones 1, 2, and 3 are 140°C, 150°C, and 155°C, respectively.
[0062] Test Example 1:
[0063] Barrier performance test:
[0064] Test method: The barrier properties of the food packaging films prepared in the examples and comparative examples were tested using a VAC-V2 differential pressure gas permeameter according to the standard GB / T 1038-2000, and the test gas was oxygen. The results are shown in Table 1.
[0065] Table 1
[0066]
[0067] From the comparison of the experimental data of Examples 1 to 3 and Comparative Examples 1 to 3 in Table 1, it can be found that the high barrier and puncture-resistant food packaging film prepared in the present invention has good barrier properties.
[0068] By comparison, the oxygen permeability coefficients of Examples 1 to 3 are smaller than those of Comparative Examples 1 to 2, indicating that after the modified polystyrene, modified vermiculite flakes and zinc chloride are melt-blended and then prepared into a film by a blow molding machine, under high temperature conditions, the cyano groups on the modified polystyrene and the modified vermiculite flakes are polymerized to form triazine groups through the action of the catalyst zinc chloride, and the modified polystyrene can also self-crosslink to form triazine groups, thereby enhancing the crosslinking density within the material and improving the barrier properties.
[0069] Test Example 2:
[0070] Antibacterial performance test:
[0071] Test method: Referring to the standard QB / T 2591-2003, the antibacterial properties of the high barrier and puncture-resistant food packaging films prepared in the examples and comparative examples were tested by the film pasting method. The results are shown in Table 2.
[0072] Table 2
[0073] Antibacterial rate (%) Antibacterial rate (%) Example 1 96.32 Comparative Example 1 27.03 Example 2 96.74 Comparative Example 2 96.17 Example 3 97.01 Comparative Example 3 96.26
[0074] From the comparison of the experimental data of Examples 1 to 3 and Comparative Examples 1 to 3 in Table 2, it can be found that the high barrier and puncture-resistant food packaging film prepared in the present invention has good antibacterial properties.
[0075] By comparison, the antibacterial rates of Examples 1 to 3 are greater than that of Comparative Example 1, indicating that in the presence of the initiator benzoyl peroxide, the grafting of polystyrene and 2-vinylhexafluoroisopropanol is initiated by free radicals, and the grafting of 2-vinylhexafluoroisopropanol can introduce hydroxyl groups into the side chains of polystyrene, and the hydroxyl groups react with 2-chloro-2-oxo-1,3,2-dioxaphospholane, and then react with 4-(dimethylamino)-2-methoxybenzonitrile to form a phosphorylcholine structure with antibacterial properties.
[0076] Test Example 3:
[0077] Mechanical properties test:
[0078] Test method: According to the standard GB / T1040.2-2006, the high barrier and puncture-resistant food packaging films prepared in the examples and comparative examples were subjected to tensile performance tests on a tensile testing machine with a gauge length of 20 mm and a tensile speed of 5 mm / min, and the tensile strength was recorded.
[0079] Anti-aging performance test:
[0080] Test method: The high barrier and puncture-resistant food packaging films prepared in the examples and comparative examples were placed in a UV light box. There were 4 Q-LabUVA340 UV lamps in the light box. The distance between the lamps was 10 cm. The distance between the sample and the lamp was 5 cm. The central wavelength of the UV light was 340 nm and the intensity was 13 mW / cm2 The size of the light box is 130cm*45cm*20cm, and the irradiation time is 720h. After the irradiation, the tensile strength is tested according to the mechanical property test method and the tensile strength retention rate before and after ultraviolet irradiation is calculated. The results are shown in Table 3.
[0081] Table 3
[0082] Tensile strength(MPa) Tensile strength retention rate (%) Example 1 54.79 92.81 Example 2 55.36 93.23 Example 3 55.61 93.46 Comparative Example 1 34.34 30.24 Comparative Example 2 47.98 55.47 Comparative Example 3 53.01 76.32
[0083] From the comparison of the experimental data of Examples 1 to 3 and Comparative Examples 1 to 3 in Table 3, it can be found that the high barrier and puncture-resistant food packaging film prepared in the present invention has good anti-aging performance.
[0084] The tensile strength of Examples 1 to 3 is greater than that of Comparative Examples 1 to 2, and the tensile strength retention rate of Examples 1 to 3 is greater than that of Comparative Examples 1 to 3, indicating that after the modified polystyrene, the modified vermiculite flakes, and zinc chloride are melt-blended, a film is prepared by a blow molding machine, and under high temperature conditions, the cyano groups on the modified polystyrene and the modified vermiculite flakes are polymerized to form triazine groups through the action of the catalyst zinc chloride. The modified polystyrene can also self-crosslink to form triazine groups, thereby enhancing the crosslinking density in the material, and while improving the mechanical properties of the material, the barrier properties are also improved; under the action of aluminum iodide, the polystyrene composite film removes the 4-(dimethylamino)-2-methoxyl group on the polystyrene side chain. The methyl group on benzonitrile forms a phenolic hydroxyl group, and the phenolic hydroxyl group and the nitrogen element on the ortho-triazine ring form an intramolecular chelate ring, which can convert light energy into heat energy to achieve anti-ultraviolet aging performance; the vermiculite flakes are modified with vinyltrimethoxysilane to make the surface of the vermiculite flakes contain double bonds, and the surface of the vermiculite flakes is modified with hydrophobic hydrogenated silicone oil and 1-(5-vinyl-2-hydroxyphenyl)ethanone by means of a silylation reaction. 1-(5-vinyl-2-hydroxyphenyl)ethanone, phosphorus oxychloride, and N,N-dimethylformamide undergo a Vilsmeier-Hacke formylation reaction to generate a flavonoid structure containing an aldehyde group. The flavonoid structure has the ability to scavenge free radicals and can resist aging.
[0085] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and scope of the equivalent elements of the claims be included in the invention. Any marking in a claim should not be considered as limiting the claim to which it relates.
Claims
1. A high barrier and puncture-resistant food packaging film, characterized in that: The high barrier and puncture-resistant food packaging film is prepared by melting and blending modified polystyrene, modified vermiculite flakes and zinc chloride, forming a film by a blow molding machine, and then reacting with iodine and aluminum powder; The modified polystyrene is obtained by grafting 2-vinylhexafluoroisopropanol onto polystyrene, reacting the polystyrene with 2-chloro-2-oxo-1,3,2-dioxaphospholane, and reacting the polystyrene with 4-(dimethylamino)-2-methoxybenzonitrile. The modified vermiculite flakes are obtained by reacting pretreated vermiculite flakes with hydrogen-containing silicone oil and 1-(5-vinyl-2-hydroxyphenyl)ethanone, then with phosphorus oxychloride and N,N-dimethylformamide, and then with hydroxylamine hydrochloride and sodium iodide.
2. A method for preparing a high barrier and puncture-resistant food packaging film, characterized in that: The method comprises the following preparation steps: (1) mixing polystyrene, benzoyl peroxide, 2-vinylhexafluoroisopropanol, and dimethyl sulfoxide to obtain hydroxylated polystyrene; (2) mixing hydroxylated polystyrene, triethylamine and tetrahydrofuran, and adding dropwise 2-chloro-2-oxy-1,3,2-dioxaphospholane solution to react to obtain a modified polystyrene precursor; mixing the modified polystyrene precursor, 4-(dimethylamino)-2-methoxybenzonitrile and tetrahydrofuran to react to obtain a modified polystyrene; (3) mixing pretreated vermiculite flakes, hydrogenated silicone oil, 1-(5-vinyl-2-hydroxyphenyl)ethanone, Custer catalyst, and dichloromethane to obtain silicone oil-modified vermiculite flakes; mixing phosphorus oxychloride and N,N-dimethylformamide, adding silicone oil-modified vermiculite flakes and N,N-dimethylformamide to react to obtain pre-modified vermiculite flakes; (4) Pre-modified vermiculite flakes, hydroxylamine hydrochloride, sodium iodide, and acetonitrile are mixed, heated to 80° C. for reaction for 2 h, and after the reaction is completed, filtered and washed with pure water for 3-4 times, and dried at room temperature to obtain modified vermiculite flakes; (5) Mixing modified polystyrene, modified vermiculite flakes and zinc chloride in a mass ratio of 1:(0.03-0.05):0.01 in a high-speed mixer at a speed of 1000 r / min for 10 min, taking out and mixing in an open mill for 5 min, with the temperature of the front roller and the rear roller of the open mill being 120° C.; then extruding and granulating by a twin-screw extruder, and preparing a film by a blow molding machine to obtain a polystyrene composite film; (6) Iodine, aluminum powder, and acetonitrile are mixed, heated to 85° C., refluxed and stirred for 3 h, cooled to room temperature, added with a polystyrene composite film, heated to 85° C., reacted for 3-4 h, and after the reaction, taken out and washed with pure water for 3-4 times, and vacuum dried at 50° C. to obtain a high barrier and puncture-resistant food packaging film.
3. The method for preparing a high barrier and puncture-resistant food packaging film according to claim 2, characterized in that: The preparation method of the hydroxylated polystyrene in step (1) is as follows: polystyrene, benzoyl peroxide, 2-vinylhexafluoroisopropanol and dimethyl sulfoxide are mixed in a mass ratio of 1: (0.002-0.003): (0.1-0.2): (20-30), and the mixture is heated to 90° C. for reaction for 1 hour, and then heated to 130-140° C. for reaction for 1 hour under nitrogen protection. After the reaction, methanol with a mass of 3-4 times that of dimethyl sulfoxide is added for precipitation, and the mixture is filtered and washed with methanol for 3-4 times. After vacuum drying at 50° C. for 24 hours, the hydroxylated polystyrene is obtained. The polystyrene model is GPPS-251.
4. The method for preparing a high barrier and puncture-resistant food packaging film according to claim 2, characterized in that: The preparation method of the modified polystyrene in step (2) is as follows: 2-chloro-2-oxy-1,3,2-dioxaphospholane and tetrahydrofuran are mixed in a mass ratio of 1:10 to obtain a 2-chloro-2-oxy-1,3,2-dioxaphospholane solution; hydroxylated polystyrene, triethylamine, tetrahydrofuran, and 2-chloro-2-oxy-1,3,2-dioxaphospholane solution are weighed in a mass ratio of 1:(0.2-0.3):(20-30):2; hydroxylated polystyrene, triethylamine, and tetrahydrofuran are mixed, cooled to -15°C, and the 2-chloro-2-oxy-1,3,2-dioxaphospholane solution is added dropwise at a dropping rate of 1mL / min, after the addition is completed, stirring is continued for 2h, and then the temperature is raised to room temperature and stirred for 2h, and tetrahydrofuran is removed by vacuum rotary evaporation and then washed with ether 3-4 times to obtain a modified polystyrene precursor; under sealed conditions, the modified polystyrene precursor, 4-(dimethylamino)-2-methoxybenzonitrile, and tetrahydrofuran are mixed in a mass ratio of 1:(0.2-0.3):(20-30), the temperature is raised to 60°C and reacted for 30-40h. After the reaction is completed, methanol 60-70 times the mass of the modified polystyrene precursor is added for precipitation, filtered, washed with pure water 3-4 times, and dried at room temperature for 24h to obtain modified polystyrene.
5. The method for preparing a high barrier and puncture-resistant food packaging film according to claim 2, characterized in that: The preparation method of the pretreated vermiculite flakes in step (3) is as follows: drying the expanded vermiculite at 80° C. for 6 hours, placing the expanded vermiculite in a planetary ball mill for grinding, and the speed of the ball mill is 600 r / min; the diameters of the grinding balls are 5 mm, 10 mm and 20 mm, and the number ratio is 4:2:1; the amount of the expanded vermiculite filled is 1 / 3 of the volume of the ball mill, and the ball milling time is 15 minutes to obtain layered vermiculite flakes; ethanol, pure water and vinyltrimethoxysilane are mixed in a mass ratio of 1:0.5:0.2, reacting at 40° C. for 1 hour, adding 0.75 times the mass of the layered vermiculite flakes of ethanol, stirring at 60° C. for 3 hours, standing at room temperature for 10 hours, filtering and washing with pure water for 3-4 times, and drying at 100° C. for 4-6 hours to obtain the pretreated vermiculite flakes; the expanded vermiculite has a particle size of 1-3 mm.
6. The method for preparing a high barrier and puncture-resistant food packaging film according to claim 2, characterized in that: The preparation method of the pre-modified vermiculite flakes in step (3) is as follows: pre-treated vermiculite flakes, hydrogenated silicone oil, 1-(5-vinyl-2-hydroxyphenyl)ethanone, Custer catalyst, and dichloromethane are mixed in a mass ratio of 1:(0.2-0.3):(0.1-0.2):0.001:(20-30), heated to 80°C and reacted for 4-6 hours. After the reaction is completed, the mixture is filtered and washed with pure water for 3-4 times, and dried at 100°C for 4-6 hours to obtain silicone oil-modified vermiculite flakes. Under nitrogen protection and at 0°C, phosphorus oxychloride and N,N-dimethylformamide were mixed at a mass ratio of 1:2 for 30 minutes, and silicone oil-modified vermiculite flakes with a mass of 5-6 times that of phosphorus oxychloride and N,N-dimethylformamide with a mass of 3 times that of phosphorus oxychloride were added and stirred for 5-6 minutes. The temperature was raised to room temperature and the reaction was continued for 4-6 hours. After the reaction was completed, the mixture was poured into an ice-water mixture, filtered and washed with pure water for 3-4 times, and dried at room temperature to obtain pre-modified vermiculite flakes. The hydrogen-containing silicone oil model was SI-H202; and the Castel catalyst was platinum (0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane.
7. The method for preparing a high barrier and puncture-resistant food packaging film according to claim 2, characterized in that: The mass ratio of the pre-modified vermiculite flakes, hydroxylamine hydrochloride, sodium iodide and acetonitrile in step (4) is 1:(0.02-0.03):(0.01-0.02):(20-30).
8. The method for preparing a high barrier and puncture-resistant food packaging film according to claim 2, characterized in that: The twin-screw extruder parameters of step (5) are as follows: the temperatures of the first, second, third and fourth zones are 195°C, 205°C, 230°C and 235°C, and the head temperature is 230°C; the blow molding machine parameters are as follows: the screw speed of the blow molding machine is 650r / min, the temperatures of the first and second zones of the mold are both 155°C, and the temperatures of the barrel zones 1, 2 and 3 are 140°C, 150°C and 155°C, respectively.
9. The method for preparing a high barrier and puncture-resistant food packaging film according to claim 2, characterized in that: The mass ratio of the polystyrene composite film, acetonitrile, iodine and aluminum powder in step (6) is: 1:(10-12):(0.7-0.8):(0.1-0.2); the particle size of the aluminum powder is 200 mesh.