Preparation method of antibacterial and antiseptic food packaging material

Abstract

The invention relates to the technical field of packaging materials, and discloses a preparation method of an antibacterial and antiseptic food packaging material, and the antibacterial and antiseptic food packaging material comprises 100 parts by weight of polyvinyl alcohol, 2-15 parts by weight of cross-linked beta-cyclodextrin included thyme oil, and 1-1.5 parts by weight of glycerol. The hyperbranched polymer cross-linked beta-cyclodextrin contains a three-dimensional hyperbranched dendritic molecular chain and has a higher inclusion amount for thyme oil, so that more active antibacterial components such as thymol and carvacrol are included, and the antibacterial and anticorrosive properties of the packaging material are remarkably improved after the hyperbranched polymer cross-linked beta-cyclodextrin is added into the polyvinyl alcohol film packaging material. The hyperbranched polymer cross-linked beta-cyclodextrin contains a flexible polyether hyperbranched molecular chain, has a certain toughening effect on polyvinyl alcohol, and is beneficial to improving the elongation at break and toughness of the polyvinyl alcohol film packaging material.

Description

Technical Field

[0001] The present invention relates to the technical field of packaging materials, and specifically to a preparation method of an antibacterial and anticorrosive food packaging material. Background Art

[0002] Polyvinyl alcohol is non-toxic, pollution-free, biodegradable, has good film-forming properties and excellent mechanical properties, and is widely used in packaging materials, adhesives, medical supplies, textile printing and dyeing, etc. In order to improve the antibacterial performance of polyvinyl alcohol and expand its practical application in antibacterial, anticorrosive and fresh-keeping of food packaging, it is usually necessary to add antibacterial agents to the polyvinyl alcohol film material, such as natural antibacterial agents, inorganic antibacterial agents, etc.

[0003] Thymol essential oil is an essential oil extracted from thyme, containing a large amount of substances such as thymol, carvacrol, eucalyptol, etc., and has strong antibacterial properties. It shows good inhibitory and killing activities against bacteria and fungi such as Escherichia coli and Staphylococcus aureus, making thymol essential oil widely used in food packaging films, fresh-keeping films, etc. For example, the literature "Preparation and Antibacterial Activity Research of PLA / PBAT / Essential Oil Active Packaging Materials" discloses that using thymol essential oil, lemon essential oil, etc. as raw materials to improve the anti-ultraviolet and antibacterial properties of PLA / PBAT films, which is a potential active packaging material. β-cyclodextrin has a unique hydrophobic cavity structure and has a good inclusion effect on compounds such as drugs and essential oils. Improving the embedding amount of β-cyclodextrin for substances such as plant essential oils and expanding its practical application in antibacterial and anticorrosive packaging film materials and other aspects is a research hotspot. Summary of the Invention

[0004] (1) Technical problems to be solved: The present invention provides an antibacterial and anticorrosive food packaging material with good mechanical properties and excellent antibacterial properties.

[0005] (2) Technical solution: A preparation method of an antibacterial and anticorrosive food packaging material: (1) Add 100 parts by weight of glycerol glycidyl ether to a solvent, and while stirring, dropwise add a solution containing 50 - 68 parts by weight of N,N'-dimethyl diamine compound. After stirring and reacting, remove the solvent by reduced pressure distillation, wash with ethanol, and dry to obtain a hydroxyl hyperbranched polymer. The reaction formula is: .

[0006] (2) Add 100 parts by weight of hydroxyl hyperbranched polymer and 200 - 500 parts by weight of β-cyclodextrin to N,N-dimethylformamide solvent, stir and then dropwise add 30 - 80 parts by weight of diisocyanate compound, stir and react in a nitrogen atmosphere, filter, wash with ethanol, and dry to obtain a hyperbranched polymer crosslinked β-cyclodextrin.

[0007] (3) Add 25 - 60 parts by weight of thymol to ethanol, stir and then add water, 100 parts by weight of hyperbranched polymer crosslinked β - cyclodextrin, stir for inclusion, filter, refrigerate the product at low temperature, and then wash it successively with water and ethanol, and dry it to obtain crosslinked β - cyclodextrin inclusion of thymol.

[0008] (4) Add 100 parts by weight of polyvinyl alcohol to water, heat and stir to dissolve, then add 2 - 15 parts by weight of crosslinked β - cyclodextrin inclusion of thymol and 1 - 1.5 parts by weight of glycerol, stir and then degas under vacuum. Pour the solution into a mold, cast and dry to form a film to obtain an antibacterial and anticorrosive food packaging material.

[0009] Preferably, the solvent in (1) is tetrahydrofuran or 1,4 - dioxane.

[0010] Preferably, in (1), the time for dropping the solution of N,N'-dimethyl diamine compound is 2 - 3 h, the temperature during the stirring reaction is 40 - 50 °C, and the reaction time is 2 - 4 h.

[0011] Preferably, the N,N'-dimethyl diamine compound is N,N'-dimethylethylenediamine, N,N'-dimethyl - 1,3 - propanediamine or N,N'-dimethyl - 1,4 - butanediamine.

[0012] Preferably, the diisocyanate compound is hexamethylene diisocyanate or isophorone diisocyanate.

[0013] Preferably, in (2), the temperature during the stirring reaction is 75 - 85 °C, and the reaction time is 2 - 4 h.

[0014] Preferably, in (3), the temperature for inclusion is 40 - 55 °C, and the time is 3 - 6 h.

[0015] (III) Technical effects of the present invention: Using glycerol glycidyl ether and N,N'-dimethyl diamine compound for ring - opening polymerization reaction to obtain dendritic hydroxy - hyperbranched polymer, and then carrying out cross - linking reaction with β - cyclodextrin and cross - linking agent diisocyanate compound. The obtained hyperbranched polymer crosslinked β - cyclodextrin contains three - dimensional hyperbranched dendritic molecular chains, and at the same time, the side chains of the hydroxy - hyperbranched polymer contain a large number of hydroxyl groups. Introducing hydroxyl groups into the hyperbranched polymer crosslinked β - cyclodextrin forms hydrogen - bond interactions with the hydroxyl groups of active ingredients such as thymol and carvacrol in thymol oil, so that the crosslinked β - cyclodextrin includes more active antibacterial ingredients such as thymol and carvacrol. Adding it to the polyvinyl alcohol film packaging material significantly improves the antibacterial and anticorrosive properties of the packaging material.

[0016] The present invention adds hyperbranched polymer crosslinked β-cyclodextrin to polyvinyl alcohol, which contains a flexible polyether hyperbranched molecular chain, and has a certain toughening effect on the polyvinyl alcohol film, which is beneficial to improving the elongation at break and toughness of the polyvinyl alcohol film packaging material. The obtained polyvinyl alcohol film packaging material has good practical applications in food packaging, freshness preservation, anti-corrosion, etc. Detailed implementation mode

[0017] 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 work belong to the scope of protection of the present invention.

[0018] The polyvinyl alcohol model in the embodiments of the present invention is 1788, provided by Xi'an Tianzheng Pharmaceutical Excipients Co., Ltd. Thymol, provided by Hubei Xinghengye Technology Co., Ltd.

[0019] Example 1: (1) Add 5 g of glycerol glycidyl ether to 40 mL of tetrahydrofuran solvent, heat to 40 °C, and dropwise add 40 mL of a tetrahydrofuran solution containing 2.5 g of N,N'-dimethyl ethylenediamine while stirring. Control the dropping time to 3 h. After dropping, continue to stir and react for 3 h. Distill off the solvent under reduced pressure, wash with ethanol, and dry to obtain a hydroxyl hyperbranched polymer.

[0020] (2) Add 2 g of hydroxyl hyperbranched polymer and 4 g of β-cyclodextrin to 80 mL of N,N-dimethylformamide solvent. After stirring, dropwise add 0.6 g of hexamethylene diisocyanate. In a nitrogen atmosphere, heat to 80 °C and stir and react for 2 h. Filter, wash with ethanol, and dry to obtain hyperbranched polymer crosslinked β-cyclodextrin.

[0021] (3) Add 2.5 g of thymol to 30 mL of ethanol. After stirring, add 50 mL of water and 10 g of hyperbranched polymer crosslinked β-cyclodextrin. Heat to 55 °C and stir for inclusion for 3 h. Filter, and keep the product refrigerated at 4 °C for 24 h. Then wash with water and ethanol in sequence and dry to obtain crosslinked β-cyclodextrin inclusion thymol. Weigh it and calculate the inclusion amount W of thymol. W = (m 1 -m 2 ) / m 2 . m 1 is the mass of crosslinked β-cyclodextrin inclusion thymol, and m 2 is the dosage of hyperbranched polymer crosslinked β-cyclodextrin.

[0022] (4) Add 100 g of polyvinyl alcohol to 800 mL of water, heat to 95 °C, stir to dissolve, cool to 60 °C, then add 2 g of crosslinked β-cyclodextrin inclusion of thymol and 1.5 g of glycerol. After stirring, perform vacuum degassing. Pour the solution into a mold, cast and dry to form a film, obtaining an antibacterial and antiseptic food packaging material.

[0023] Example 2: (1) Add 5 g of glycerol glycidyl ether to 40 mL of 1,4-dioxane solvent, heat to 40 °C, and while stirring, dropwise add 40 mL of a 1,4-dioxane solution containing 3.4 g of N,N'-dimethyl-1,4-butanediamine. Control the dropping time to 3 h. After dropping, continue stirring and reacting for 4 h. Remove the solvent by vacuum distillation, wash with ethanol, and dry to obtain a hydroxyl hyperbranched polymer.

[0024] (2) Add 2 g of hydroxyl hyperbranched polymer and 6 g of β-cyclodextrin to 100 mL of N,N-dimethylformamide solvent. After stirring, dropwise add 0.9 g of hexamethylene diisocyanate. In a nitrogen atmosphere, heat to 75 °C and stir and react for 4 h. Filter, wash with ethanol, and dry to obtain hyperbranched polymer crosslinked β-cyclodextrin.

[0025] (3) Add 3.5 g of thymol to 30 mL of ethanol. After stirring, add 80 mL of water and 10 g of hyperbranched polymer crosslinked β-cyclodextrin. Heat to 40 °C and stir for inclusion for 6 h. Filter, and keep the product refrigerated at 4 °C for 24 h. Then wash with water and ethanol in sequence and dry to obtain crosslinked β-cyclodextrin inclusion of thymol. Weigh and calculate the inclusion amount W of thymol. W = (m 1 - m 2 ) / m 2 . m 1 is the mass of crosslinked β-cyclodextrin inclusion of thymol, and m 2 is the dosage of hyperbranched polymer crosslinked β-cyclodextrin.

[0026] (4) Add 100 g of polyvinyl alcohol to 900 mL of water, heat to 95 °C, stir to dissolve, cool to 60 °C, then add 6 g of crosslinked β-cyclodextrin inclusion of thymol and 1 g of glycerol. After stirring, perform vacuum degassing. Pour the solution into a mold, cast and dry to form a film, obtaining an antibacterial and antiseptic food packaging material.

[0027] Example 3: (1) Add 5 g of glycerol glycidyl ether to 40 mL of 1,4-dioxane solvent, heat to 50 °C, and while stirring, dropwise add a 1,4-dioxane solution containing 2.5 g of N,N'-dimethylethylenediamine over 50 mL. Control the dropping time to 2 h. After the dropping is complete, continue stirring and reacting for 2 h. Remove the solvent by vacuum distillation, wash with ethanol, and dry to obtain a hydroxyl hyperbranched polymer.

[0028] (2) Add 2 g of hydroxyl hyperbranched polymer and 8 g of β-cyclodextrin to 120 mL of N,N-dimethylformamide solvent. After stirring, dropwise add 1.3 g of isophorone diisocyanate. In a nitrogen atmosphere, heat to 85 °C and stir and react for 3 h. Filter, wash with ethanol, and dry to obtain a hyperbranched polymer crosslinked β-cyclodextrin.

[0029] (3) Add 4.8 g of thymol to 30 mL of ethanol. After stirring, add 60 mL of water and 10 g of hyperbranched polymer crosslinked β-cyclodextrin. Heat to 45 °C and stir for inclusion for 5 h. Filter, and refrigerate the product at 4 °C for 24 h. Then wash with water and ethanol in sequence and dry to obtain β-cyclodextrin crosslinked inclusion of thymol. Weigh and calculate the inclusion amount W of thymol. W = (m 1 - m 2 ) / m 2 . m 1 is the mass of β-cyclodextrin crosslinked inclusion of thymol, and m 2 is the dosage of hyperbranched polymer crosslinked β-cyclodextrin.

[0030] (4) Add 100 g of polyvinyl alcohol to 900 mL of water, heat to 95 °C, stir to dissolve, cool to 60 °C, then add 10 g of β-cyclodextrin crosslinked inclusion of thymol and 1 g of glycerol. After stirring, perform vacuum degassing, pour the solution into a mold, cast and dry to form a film to obtain an antibacterial and anticorrosive food packaging material.

[0031] Example 4: (1) Add 5 g of glycerol glycidyl ether to 50 mL of tetrahydrofuran solvent, heat to 45 °C, and while stirring, dropwise add a tetrahydrofuran solution containing 2.9 g of N,N'-dimethyl-1,3-propanediamine over 50 mL. Control the dropping time to 3 h. After the dropping is complete, continue stirring and reacting for 4 h. Remove the solvent by vacuum distillation, wash with ethanol, and dry to obtain a hydroxyl hyperbranched polymer.

[0032] (2) Add 2 g of hydroxyl hyperbranched polymer and 10 g of β-cyclodextrin to 150 mL of N,N-dimethylformamide solvent. After stirring, dropwise add 1.6 g of hexamethylene diisocyanate. In a nitrogen atmosphere, heat to 80 °C and stir and react for 4 h. Filter, wash with ethanol, and dry to obtain a hyperbranched polymer crosslinked β-cyclodextrin.

[0033] (3) Add 6 g of thymol to 30 mL of ethanol. After stirring, add 80 mL of water and 10 g of hyperbranched polymer crosslinked β-cyclodextrin. Heat to 55 °C and stir for inclusion for 6 h. Filter, refrigerate the product at 4 °C for 24 h, then wash successively with water and ethanol, and dry to obtain crosslinked β-cyclodextrin inclusion of thymol. Weigh it and calculate the inclusion amount W of thymol. W = (m 1 - m 2 ) / m 2 . m 1 is the mass of crosslinked β-cyclodextrin inclusion of thymol, and m 2 is the dosage of hyperbranched polymer crosslinked β-cyclodextrin.

[0034] (4) Add 100 g of polyvinyl alcohol to 900 mL of water. Heat to 95 °C, stir to dissolve, cool to 60 °C, then add 15 g of crosslinked β-cyclodextrin inclusion of thymol and 1.5 g of glycerol. After stirring, carry out vacuum degassing, pour the solution into a mold, cast and dry to form a film to obtain an antibacterial and antiseptic food packaging material.

[0035] Comparative Example 1: (1) Add 100 g of polyvinyl alcohol to 800 mL of water. Heat to 95 °C, stir to dissolve, cool to 60 °C, then add 1.5 g of glycerol. After stirring, carry out vacuum degassing, pour the solution into a mold, cast and dry to form a film to obtain a food packaging material.

[0036] Comparative Example 2: (1) Add 5 g of ethylene glycol diglycidyl ether to 40 mL of tetrahydrofuran solvent. Heat to 40 °C, and while stirring, dropwise add 40 mL of a tetrahydrofuran solution containing 2.5 g of N,N'-dimethylethylenediamine. Control the dropping time to 3 h. After dropping, continue stirring and reacting for 3 h. Distill off the solvent under reduced pressure, wash with ethanol, and dry to obtain a hydroxyl polymer.

[0037] (2) Add 2 g of hydroxyl polymer and 4 g of β-cyclodextrin to 80 mL of N,N-dimethylformamide solvent. After stirring, dropwise add 0.6 g of hexamethylene diisocyanate. In a nitrogen atmosphere, heat to 80 °C and stir and react for 2 h. Filter, wash with ethanol, and dry to obtain crosslinked β-cyclodextrin.

[0038] (3) Add 2.5 g of thymol to 30 mL of ethanol. After stirring, add 50 mL of water and 10 g of crosslinked β-cyclodextrin. Heat to 55 °C and stir for inclusion for 3 h. Filter, refrigerate the product at 4 °C for 24 h, then wash successively with water and ethanol, and dry to obtain crosslinked β-cyclodextrin inclusion of thymol. Weigh it and calculate the inclusion amount W of thymol. W = (m 1 - m 2 ) / m2 . m 1 is the mass of cross-linked β-cyclodextrin inclusion of thymol, m 2 is the dosage of cross-linked β-cyclodextrin.

[0039] (4) Add 100 g of polyvinyl alcohol to 800 mL of water, heat to 95 °C, stir to dissolve, cool to 60 °C, then add 2 g of cross-linked β-cyclodextrin inclusion of thymol and 1.5 g of glycerol. After stirring, carry out vacuum degassing, pour the solution into a mold, cast and dry to form a film to obtain an antibacterial and anticorrosive food packaging material.

[0040] Comparative Example 3: (1) Add 4 g of β-cyclodextrin to 80 mL of N,N-dimethylformamide solvent, stir and then dropwise add 0.6 g of hexamethylene diisocyanate. In a nitrogen atmosphere, heat to 80 °C and stir for 2 h. Filter, wash with ethanol, and dry to obtain cross-linked β-cyclodextrin.

[0041] (2) Add 2.5 g of thymol to 30 mL of ethanol, stir and then add 50 mL of water and 10 g of cross-linked β-cyclodextrin. Heat to 55 °C and stir for inclusion for 3 h. Filter, and refrigerate the product at 4 °C for 24 h. Then wash with water and ethanol in sequence and dry to obtain cross-linked β-cyclodextrin inclusion of thymol. Weigh and calculate the inclusion amount W of thymol. W = (m 1 - m 2 ) / m 2 . m 1 is the mass of cross-linked β-cyclodextrin inclusion of thymol, m 2 is the dosage of cross-linked β-cyclodextrin.

[0042] (3) Add 100 g of polyvinyl alcohol to 800 mL of water, heat to 95 °C, stir to dissolve, cool to 60 °C, then add 2 g of cross-linked β-cyclodextrin inclusion of thymol and 1.5 g of glycerol. After stirring, carry out vacuum degassing, pour the solution into a mold, cast and dry to form a film to obtain an antibacterial and anticorrosive food packaging material.

[0043] Table 1

[0044] The antibacterial performance of the packaging material was tested by the oscillation method. The test strains were Escherichia coli, Staphylococcus aureus and Candida albicans respectively.

[0045] Take 10 mL of a concentration of 10 5The activated bacterial suspension of cfu / mL was added to a sterilized test tube, and the packaging material sample was added. The packaging material of Comparative Example 1 was used as the blank group. In a constant temperature incubator, it was shaken at 37 °C for 24 h, and the shaking rate was 200 r / min. Then, the bacterial solution was serially diluted 10-fold with PBS buffer solution. 1 mL of the diluted bacterial solution was taken and inoculated in an agar medium. It was cultured at 37 °C for 24 h in a constant temperature incubator. After culturing, colony counting was performed. Each sample was tested 3 times, and the average value was taken. The antibacterial rate Q was calculated.

[0046] Q = (B - C) / B × 100%. B is the number of colonies after culturing in the blank group. C is the number of colonies after culturing in the experimental group.

[0047] Table 2

[0048] Referring to the ISO527-3-2018 standard, a universal material testing machine was used to test the tensile properties of the packaging material. The size of the specimen was 100 mm × 10 mm. The gauge length was 50 mm, and the tensile rate was 5 mm / min.

[0049] Table 3

[0050] After testing, in each example, using a hydroxyl hyperbranched polymer, β-cyclodextrin, and a diisocyanate compound as raw materials, the prepared hyperbranched polymer crosslinked β-cyclodextrin has a higher inclusion amount of thymol. This is because the hydroxyl hyperbranched polymer contains a three-dimensional hyperbranched dendritic molecular chain. After crosslinking with β-cyclodextrin and diisocyanate, a three-dimensional spatial crosslinked network structure is formed, which has a higher inclusion amount of thymol. At the same time, the side chain of the hydroxyl hyperbranched polymer contains a large number of hydroxyl groups. By introducing hydroxyl groups into the hyperbranched polymer crosslinked β-cyclodextrin, hydrogen bond interactions are formed with active ingredients such as thymol and carvacrol in thymol oil. As a result, the crosslinked β-cyclodextrin incorporates more antibacterial components such as thymol and carvacrol. When added to the polyvinyl alcohol film packaging material, the antibacterial and anti-corrosion properties of the packaging material are significantly improved. And by adding an appropriate amount of hyperbranched polymer crosslinked β-cyclodextrin, the elongation at break of the packaging material has a certain improvement effect. It may be that the hyperbranched polymer crosslinked β-cyclodextrin contains a flexible polyether hyperbranched molecular chain, which has a certain toughening effect on polyvinyl alcohol, facilitating the improvement of the elongation at break and toughness.

[0051] In Comparative Example 2, ethylene glycol diglycidyl ether and N,N'-dimethylethylenediamine were used for reaction, and the resulting hydroxyl polymer had a linear molecular chain and did not contain a three-dimensional hyperbranched dendritic molecular chain; in Comparative Example 3, no hydroxyl hyperbranched polymer was added in the preparation of crosslinked β-cyclodextrin, and the resulting crosslinked cyclodextrin did not form a good three-dimensional spatial crosslinked network structure, and the inclusion amount of thymol was low, resulting in poor antibacterial performance of the polyvinyl alcohol film packaging material.

Claims

1. A method for preparing an antibacterial and antiseptic food packaging material, characterized in that: The preparation method is: (1) Add glycerol glycidyl ether to a solvent, and dropwise add a solution containing an N,N'-dimethyldiamine compound while stirring, and after stirring for reaction, perform vacuum distillation, wash, and dry to obtain a hydroxy hyperbranched polymer; (2) Adding a hydroxy hyperbranched polymer and β-cyclodextrin to an N,N-dimethylformamide solvent, adding a diisocyanate compound dropwise after stirring, stirring and reacting in a nitrogen atmosphere, filtering, washing, and drying to obtain a hyperbranched polymer cross-linked β-cyclodextrin; (3) adding thyme oil to ethanol, stirring and then adding water, cross-linking β-cyclodextrin with a hyperbranched polymer, stirring for inclusion, filtering, refrigerating the product at low temperature, washing, and drying to obtain cross-linked β-cyclodextrin inclusion thyme oil; (4) Add 100 parts by weight of polyvinyl alcohol to water, heat and stir to dissolve, then add 2-15 parts by weight of cross-linked β-cyclodextrin inclusion thyme oil and 1-1.5 parts by weight of propylene glycol, stir and degas in vacuum, pour the solution into a mold, cast and dry to form a film, and obtain an antibacterial and antiseptic food packaging material.

2. The method for preparing the antibacterial and antiseptic food packaging material according to claim 1, characterized in that: The solvent in (1) is tetrahydrofuran or 1,4-dioxane.

3. The method for preparing the antibacterial and antiseptic food packaging material according to claim 1, characterized in that: In the above (1), the amount of glycerol glycidyl ether is 100 parts by weight, and the amount of N,N'-dimethyldiamine compound is 50-68 parts by weight.

4. The method for preparing the antibacterial and antiseptic food packaging material according to claim 1, characterized in that: In the step (1), the time for dripping the solution of the N,N'-dimethyldiamine compound is controlled to be 2-3 hours, the temperature during the stirring reaction is 40-50°C, and the reaction time is 2-4 hours.

5. The method for preparing the antibacterial and antiseptic food packaging material according to claim 4, characterized in that: The N,N'-dimethyldiamine compound is N,N'-dimethylethylenediamine, N,N'-dimethyl-1,3-propylenediamine or N,N'-dimethyl-1,4-butanediamine.

6. The method for preparing the antibacterial and antiseptic food packaging material according to claim 1, characterized in that: In the above (2), the amount of the hydroxy hyperbranched polymer is 100 parts by weight, the amount of β-cyclodextrin is 200-500 parts by weight, and the amount of the diisocyanate compound is 30-80 parts by weight.

7. The method for preparing the antibacterial and antiseptic food packaging material according to claim 6, characterized in that: The diisocyanate compound is hexamethylene diisocyanate or isophorone diisocyanate.

8. The method for preparing the antibacterial and antiseptic food packaging material according to claim 1, characterized in that: The stirring reaction temperature in (2) is 75-85°C, and the reaction time is 2-4h.

9. The method for preparing the antibacterial and antiseptic food packaging material according to claim 1, characterized in that: The temperature during the inclusion in step (3) is 40-55°C and the time is 3-6 hours.

10. The method for preparing the antibacterial and antiseptic food packaging material according to claim 1, characterized in that: In the (3), the amount of the hyperbranched polymer cross-linked β-cyclodextrin is 100 parts by weight, and the amount of thyme oil is 25-60 parts by weight.

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