CN115058921A

CN115058921A - Preparation method of self-heating sealing antibacterial food packaging paper

Info

Publication number: CN115058921A
Application number: CN202210755473.7A
Authority: CN
Inventors: 伊财富; 杨菊红; 汪静燕; 徐冰; 雷涛; 刘巧红
Original assignee: Zhejiang Hengda New Material Co ltd
Current assignee: Zhejiang Hengda New Material Co ltd
Priority date: 2022-06-29
Filing date: 2022-06-29
Publication date: 2022-09-16

Abstract

The invention discloses a preparation method of self-heating sealing antibacterial food wrapping paper. The food packaging paper prepared by the invention has the advantages of self-heat sealing, degradability, antibacterial property and high barrier property, and is convenient to obtain raw materials and low in cost.

Description

Preparation method of self-heating sealing antibacterial food packaging paper

Technical Field

The invention relates to the technical field of oil-proof paper, in particular to a preparation method of self-heat-sealing antibacterial food packaging paper.

Background

With the continuous reduction of fossil energy and the increasing severity of the problems that plastic wastes are difficult to degrade, the development of degradable materials receives more and more attention. In recent years, with the continuous progress of society, the food packaging industry is rapidly developed, and in addition, people pay attention to the problems of food sanitation and food safety, so that the development of the paper-based food packaging material with antibacterial and self-heating sealing performances is an effective way for replacing plastic packaging materials.

However, due to the porous structure of the paper and the capillary phenomenon of the fibers, the base paper has poor oil and water resistance and low barrier capability to oxygen and water vapor. In addition, because the food packaging paper is used as a food packaging material in a special application, the food packaging paper is required to meet the characteristics of health, non-toxicity and the like, and therefore substances such as adhesives and the like are avoided as much as possible in the process of packaging food. The chitosan is a natural polysaccharide substance, has good film-forming property, shows good compatibility with cellulose, has higher biocompatibility and good antibacterial property, and can provide good oil-proof effect for food packaging materials. However, chitosan molecular chains contain a large number of hydrophilic groups such as hydroxyl, amino and the like, so that the chitosan has high water absorption performance, and the application of the chitosan in food packaging is limited. The nanocellulose (LCNFs) containing lignin is used as a novel functional material, has the advantages of high mechanical strength, no toxicity, reproducibility, good biocompatibility, biodegradability and the like, and the lignin containing the nanocellulose can provide a good hydrophobic effect for the nanocellulose. In addition, zein is a plant protein widely existing in plants, is rich in hydrophobic amino acid and sulfur-containing amino acid, has good film forming property and hydrophobic property, and is often used as a multifunctional food material and an additive. Therefore, the preparation of the self-heat-sealing antibacterial food packaging paper by using simple processes and raw materials is of great significance.

Disclosure of Invention

The invention aims to provide a preparation method of self-heat-sealing antibacterial food packaging paper. The food packaging paper prepared by the invention has the advantages of self-heat sealing, degradability, antibacterial property and high barrier property, and is convenient to obtain raw materials and low in cost.

The technical scheme of the invention is as follows: a preparation method of self-heating sealing antibacterial food wrapping paper comprises the steps of sequentially coating the surface of base paper by using a chitosan solution and LCNFs suspension, then drying and calendaring to obtain a double-layer coated sample, and then coating the double-layer coated sample by using a zein solution to obtain a finished product.

The preparation method of the self-heating sealing antibacterial food packaging paper comprises the steps that the mass concentration of the chitosan solution is 0.2-3%, and the coating weight is 0.1g/m ² -1.2g/m ² 。

In the preparation method of the self-heat-sealing antibacterial food packaging paper, the chitosan solution is prepared by adding chitosan into an acetic acid solution with a volume fraction of 2%, and stirring for 20-30h at a rotation speed of 250rpm and 100-.

In the preparation method of the self-heat-sealing antibacterial food packaging paper, the concentration of the LCNFs suspension is 0.1-1.2 wt%, and the coating weight is 0.1g/m ² -1.2g/m ² 。

In the preparation method of the self-heat-sealing antibacterial food wrapping paper, the LCNFs suspension is prepared by soaking the crushed pulp board in water for 20-30 hours, dispersing the pulp by using a tile power beater, adjusting the pulp concentration to 1.0-2 wt%, and grinding the pulp by using an ultrafine particle nano mill: grinding the slurry for pretreatment, adjusting the disc grinding clearance to zero, wherein the rotating speed is 1000-1300rpm, and circularly grinding for 5-15 times under the condition of the disc grinding clearance of 0 mu m; then adjusting the disc grinding gap to-50 μm, increasing the rotation speed to 1400-1600rpm, and circularly grinding for 5-10 times; adjusting the rotating speed to 1800-2200rpm, circularly grinding for 5-15 times by a disc grinding clearance of-80 mu m, and finally circularly grinding for 30-50 times by a disc grinding clearance of-100 mu m to obtain a semi-finished product of the LCNFs suspension, adding a proper amount of deionized water into the semi-finished product of the LCNFs suspension for dilution, and dispersing by a high-shear disperser to finally obtain the LCNFs suspension with the concentration of 0.1-1.2 wt%.

In the preparation method of the self-heat-sealing antibacterial food wrapping paper, the mass concentration of the zein solution is 2-10%, and the coating weight is 0.5g/m ² -6g/m ² 。

The preparation method of the self-heat-sealing antibacterial food wrapping paper comprises the steps of dissolving zein in an ethanol solution with the volume fraction of 85%, and stirring for 8-15 hours at the rotating speed of 400-600rpm by using a magnetic stirrer.

In the preparation method of the self-heating sealing antibacterial food packaging paper, the calendering temperature of the drying calendering treatment is 100-200 ℃, and the pressure is 0.2-0.4 MPa.

Compared with the prior art, the invention uses chitosan solution and LCNFs suspension to coat the surface of the base paper in sequence, then obtains a double-layer coated sample by drying and calendaring treatment, then uses zein solution to coat the double-layer coated sample, and prepares the self-heating sealing antibacterial food packaging paper in sequence. The food packaging paper prepared by the invention has good waterproof and oilproof effects, the three-layer coating paper can effectively inhibit the permeability of water vapor and oxygen, in addition, the mechanical strength of the base paper after coating treatment can be obviously improved, and the barrier property is excellent. According to the invention, the zein is used as the outermost layer to be coated, so that good self-heat sealing capability can be provided for the food wrapping paper, the effect that the food wrapping paper can be used for packaging food without using an adhesive is realized, and meanwhile, the chitosan has good antibacterial performance, so that the food wrapping paper prepared by the method can inhibit the growth of bacteria in the food packaging process and the storage process, and the safety of the food is improved.

Drawings

FIG. 1 is a graph of the effect of chitosan dosage on oil repellency rating and brighness value in chitosan single layer coated paper;

FIG. 2 is a graph of the effect of LCNFs usage on oil repellency rating and mutual tack in a chitosan inner, LCNFs outer double coated paper;

FIG. 3 is a graph showing the effect of zein content on oil repellency rating and brighness value in three coated sheets, chitosan inner, LCNFs middle and zein outer;

FIG. 4 shows zein at 4.0g/m ² And the influence of the heat-sealing temperature on the peel strength when the heat-sealing pressure is 0.4 MPa;

FIG. 5 shows zein at 4.0g/m ² And the influence of the heat-sealing pressure on the peel strength under the condition that the heat-sealing temperature is 150 ℃;

FIG. 6 is a graph of the effect of zein dosage on peel strength of three layers of coated paper after heat sealing;

FIGS. 7a and b are the rupture condition of the three-layer coated paper after heat-sealing stripping under the conditions of 180 ℃ and 150 ℃; FIG. 7c is a process of self-heating packaging of food with three layers of coated paper;

FIGS. 8a and b are graphs for testing the antibacterial performance of the food wrapper and the base paper of the present invention against Escherichia coli and Staphylococcus aureus, respectively;

FIG. 9 is a graph of cell viability in three layers of coated paper leachate;

FIG. 10 is a fluorescent electron micrograph of cells in three layers of coated paper leachate.

Detailed Description

The following examples further illustrate the invention but are not to be construed as limiting the invention.

Example (b): a method for preparing self-heating sealing antibacterial food wrapping paper comprises preparing chitosan solution, LCNFs suspension and zein solution.

The chitosan solution is prepared by dissolving 1.0g of chitosan in 50mL of 2.0% acetic acid solution by volume fraction, and magnetically stirring at 200rpm in room temperature environment for 24h to obtain uniform chitosan solution with concentration of 2.0% (W/V). And then adding a proper amount of deionized water into the obtained 2.0% chitosan solution, and magnetically stirring for 24 hours at the rotating speed of 200rpm in a room temperature environment to finally obtain 0.4%, 0.8%, 1.2%, 1.6% and 2.0% (W/V) chitosan solution, and storing at 4 ℃ for use.

The zein solution is prepared by adding 5.0g zein into 50mL 85.0% ethanol solution, and magnetically stirring at 500rpm at room temperature for 12h to obtain uniform zein solution with concentration of 10.0% (W/V). And then adding a proper amount of 85% ethanol solution into the 10.0% zein solution, magnetically stirring for 12 hours at 500rpm in a room temperature environment to finally obtain 2.0%, 4.0%, 6.0%, 8.0% and 10.0% (W/V) zein solution, and storing and using the lignin-containing nanocellulose (LCNFs) at 4 ℃. Then adjusting the concentration of the slurry to 1.0 wt%, grinding the slurry by using an ultra-fine particle nano mill, firstly grinding the slurry for pretreatment, zeroing the disc mill gap, rotating at 1200rpm, and circularly grinding for 10 times under the condition of the disc mill gap of 0 mu m; then adjusting the disc grinding gap to-50 μm, increasing the rotation speed to 1500 rpm, and circularly grinding for 10 times; the rotation speed was adjusted to 2000rpm, and the mixture was cyclically ground 10 times with a disc mill gap of-80 μm and finally 40 times with a disc mill gap of-100 μm to give a suspension of LCNFs at a concentration of 1.0 wt%. And adding a proper amount of deionized water into the obtained LCNFs suspension for dilution, and dispersing by using a high-shear disperser to finally obtain the LCNFs suspension with the concentration of 0.2 wt%, 0.4 wt%, 0.6 wt%, 0.8 wt% and 1.0 wt%, and storing at 4 ℃ for use.

After the chitosan solution, the LCNFs suspension and the zein solution are prepared, the raw paper is coated by the single-layer chitosan solution, the LCNFs suspension or the zein solution respectively, and the coating of the method (multi-layer surface) is also carried out.

The chitosan solution is coated by selecting the low quantitative amount of 40g/m ² The base paper of (1) was surface-coated with 2.5mL of chitosan coating solution, and the coating was performed using an XT-300 coater, and dried at room temperature after the coating was completed. The prepared compounds were used in amounts of 0.4%, 0.8%, 1.2%, 1.6%,2.0% (W/V) of chitosan solution was coated to obtain coating amounts of 0.2g/m, respectively ² ， 0.4g/m ² ，0.6g/m ² ，0.8g/m ² ，1.0g/m ² The chitosan coated paper is marked as C-0.2, C-0.4, C-0.6, C-0.8 and C-1.0 respectively.

The LCNFs suspension is coated by selecting base paper with low basis weight of 40g/m2 for surface coating, the using amount of the LCNFs coating liquid is 5.0mL, coating is carried out by using an XT-300 coating machine, and drying is carried out at room temperature after coating is finished. LCNFs coated papers with coating weights of 0.2g/m2, 0.4g/m2, 0.6g/m2, 0.8g/m2 and 1.0g/m2, respectively marked as L-0.2, L-0.4, L-0.6, L-0.8 and L-1.0, were finally obtained by coating with the prepared LCNFs suspensions of 0.2, 0.4, 0.6, 0.8 and 1.0 wt%, respectively.

The zein solution is coated by selecting low basis weight of 40g/m ² The base paper of (1) is coated on the surface, the using amount of the zein coating liquid is 2.5mL, the base paper is coated by an XT-300 coating machine, and the base paper is dried at room temperature after the coating is finished. Respectively coating with the prepared zein solution of 2.0%, 4.0%, 6.0%, 8.0%, and 10.0%, to obtain final coating weight of 1.0g/m ² ，2.0g/m ² ，3.0g/m ² ，4.0g/m ² ，5.0g/m ² The zein coated paper of (1) is marked as Z-1.0, Z-2.0, Z-3.0, Z-4.0 and Z-5.0 respectively.

The coating adopted in the embodiment is multilayer surface coating, the chitosan solution and the LCNFs suspension are used for sequentially coating the surface of the base paper, then the drying calendaring treatment (the calendaring temperature of the drying calendaring treatment is 100-200 ℃, and the pressure is 0.2-0.4 MPa.) is carried out to obtain a double-layer coated sample (marked as C-L), and then the zein solution is used for coating the double-layer coated sample to obtain a finished product (marked as C-L-Z). Wherein chitosan is used as an inner coating layer, LCNFs are used as an intermediate coating layer, and zein is used as an outermost coating layer, and the coating method is the same as that of the single-layer coating.

FIG. 1 is a graph of the effect of chitosan dosage on oil repellency rating and brighness value in chitosan single layer coated paper; FIG. 2 shows the inner layer of chitosanThe influence of the LCNFs dosage in the LCNFs outer double coated paper on the oil resistance level and the brighness value; FIG. 3 is a graph showing the effect of zein content on oil repellency rating and brighness value in three coated sheets, chitosan inner, LCNFs middle and zein outer; as can be seen from fig. 1, the base paper has an oil-proof rating of 0 and does not have oil-proof performance, because the base paper is formed by interweaving fibers, a porous structure and a rough surface structure are formed among the fibers, and in addition, the fibers have capillary action, and in addition, the cellulose has strong polarity, so that the base paper is easy to absorb oil and water. When the chitosan is coated as a first layer, the oil resistance grade of the chitosan single-layer coated paper is obviously improved along with the increase of the dosage of the chitosan, and when the dosage of the chitosan is increased to 1.0g/m ² When the oil resistance is improved to 6 grades, the chitosan has good oil resistance. But with the increase of the dosage of the chitosan, the water absorption of the chitosan single-layer coated paper is obviously improved, the base paper bobbiness value is 18.8g/m2, and when the dosage of the chitosan is 1.0g/m ² When the blowability value is increased to 20.9g/m ² . FIG. 2 shows the effect of the amount of LCNFs used on the oil repellency rating and water absorbency of a two-ply coated paper with chitosan as the inner layer and LCNFs as the outer layer. As can be seen from FIG. 2, the LCNFs coating layer further improves the oil resistance of the double-coated paper on the basis of the coating of the chitosan inner layer, and when the LCNFs is used in an amount of 1.0g/m ² And meanwhile, the oil resistance level reaches 9 levels. The water absorption of the double-layer coated paper is obviously reduced along with the increase of the using amount of the LCNFs, and the brighness value is 20.9g/m when the double-layer coated paper is not coated with the LCNFs ² When the LCNFs dosage is increased to 1.0g/m ² When the blowability value is lowered to 14.14g/m ² . FIG. 3 is a graph of the effect of zein usage on the oil repellency rating and water absorbency of a three-layer coated paper with inner chitosan, middle LCNFs and outer zein. On the basis of double-layer coating, the oil resistance of the three-layer coated paper is further improved along with the increase of the zein, and when the zein content is higher than 4.0g/m 2, the oil resistance is 12. It is noteworthy that the absorption performance of the three-layer coated paper is greatly reduced with the increase of zein, and when the zein content is higher than 5.0g/m2, the bokeh value is only 2.60g/m2, and the surface jadeThe water resistance can be effectively improved by adding the rice prolamin.

From the above results, it is found that the paper coated with the three layers of chitosan, LCNFs and zein has good water and oil proofing effects, and the three-layer coated paper (i.e. the food packaging paper prepared by the invention) can effectively inhibit the permeability of water vapor and oxygen, and the mechanical strength of the coated paper is obviously improved. The results show that the three-layer coated paper can meet the requirement of barrier property of food packaging paper. At present, food packaging paper is made into food packaging bags or food packaging boxes by using adhesives when food is packaged. The adhesive contains a large amount of carcinogenic substances, can cause harm to human bodies, and is not suitable for application in the food packaging industry. Therefore, the research on the food packaging material with self-heat-sealing capability can effectively solve the use problem of the adhesive and improve the safety of the food packaging paper. The applicant respectively tests the self-heat-sealing capability of single-layer coated paper made of three coating materials, namely chitosan, LCNFs and zein, at the temperature of 90-180 ℃. The results are shown in Table 1 ("-" is not self-heat-sealable; "√" is self-heat-sealable):

	90	100	110	120	130	140	150	160	170	180
											base paper	-	-	-	-	-	-	-	-	-	-
Chitosan	-	-	-	-	-	-	-	-	-	-
											LCNFs	-	-	-	-	-	-	-	-	-	-
Zein	√	√	√	√	√	√	√	√	√	√

Table 1 (self-heat sealing performance of base paper, chitosan single-layer coated paper, LCNFs single-layer coated paper, and zein single-layer coated paper)

As can be seen from the results of table 1, none of the base paper, the chitosan single-layer coated paper, and the LCNFs single-layer coated paper had self-heat-sealing ability, and only the zein single-layer coated paper had self-heat-sealing ability in the range of 90 ℃ to 180 ℃. In addition, when the heat-sealing temperature is lower than 90 ℃, the zein single-layer coated paper cannot realize the self-heat-sealing effect.

Subsequently, the applicants tested the effect of heat seal temperature, heat seal pressure and zein level on the peel strength of the three-layer coated paper after heat sealing. FIG. 4 shows zein at 4.0g/m ² And the heat-sealing pressure is 0.4MPa, the influence of the heat-sealing temperature on the peel strength shows that the peel strength tends to increase and then decrease with the increasing heat-sealing temperature, and the peel strength is maximum at 150 ℃. In testing the Heat sealThe peel strength of the latter sample was found to be low at the interface after heat sealing in the case of high temperature and pressure after the temperature exceeded 150 ℃, so that the fracture occurred at the seal when the peel strength was tested (as shown in a and b of fig. 7, the fracture after heat sealing peel under the conditions of 180 ℃ (a) and 150 ℃ (b) for three-layer coated paper). Therefore 150 ℃ was chosen as the heat sealing temperature for the three-layer coated food paper prepared. On this basis, the effect of heat-seal pressure on peel strength was further tested. FIG. 5 shows zein at 4.0g/m ² And under the condition that the heat sealing temperature is 150 ℃, the influence graph of the heat sealing pressure on the peel strength is shown, in the range of 0.1MPa-0.5MPa, the peel strength of the three-layer coated paper after heat sealing is obviously increased along with the continuous increase of the heat sealing pressure, and the peel strength is not obviously increased after the pressure is increased to 0.4MPa, so 0.4MPa is selected as the heat sealing pressure. Then, the influence of the zein dosage on the peel strength of the three-layer coated paper after heat sealing is studied, as shown in fig. 6, the peel strength gradually increases with the zein dosage, and finally, when the heat sealing temperature is 150 ℃, the heat sealing pressure is 0.4MPa, and the zein dosage is 5g/m ² The peel strength after heat sealing of the three-layer coated paper was 372N/m. The results show that the zein coated as the outermost layer can provide good self-heat sealing capability for food wrapping paper, realize the effect that the food paper can be used for packaging food without using an adhesive (as shown in c in figure 7), and open up a new way for the wide and safe application of the food paper.

Furthermore, as the antibacterial performance and the biocompatibility are also key indexes of the food packaging material, the food packaging material with good antibacterial performance can effectively inhibit the growth of bacteria, prolong the shelf life of food and ensure the quality safety of the food. The food packaging material is required to be non-toxic and healthy, so that the natural antibacterial material which is green, environment-friendly and high in biocompatibility is the best choice of the antibacterial food packaging material. The applicant analyzed the antibacterial property and biocompatibility of the three-layer coated food packaging paper. The antibacterial effect of the three-layer coated paper on escherichia coli and staphylococcus aureus was detected by the antibacterial ring method, and the result is shown in fig. 8. FIGS. 8a and b are graphs showing the antibacterial performance of the food wrapper and the base paper of the present invention against Escherichia coli and Staphylococcus aureus, respectively. No bacteria inhibition area and obvious inhibition zone are found in the base paper without any coating, and the surface base paper has almost no inhibition effect on escherichia coli and staphylococcus aureus. The three-layer coated paper can see obvious bacteria inhibition areas in factory bacillus and staphylococcus aureus, and the widths of inhibition zones are 2.3mm and 2.5mm respectively. This indicates that the three-layer coated paper can effectively inhibit the growth and reproduction of gram-negative escherichia coli and gram-positive staphylococcus aureus. This is because chitosan is a natural polysaccharide substance and has a broad-spectrum antibacterial property. The three-layer coated food paper shows good antibacterial performance, can inhibit the growth of bacteria in the process of packaging food and the process of storing food, and improves the safety of food.

Since the food packaging material is in close contact with food during packaging, storage and transportation, the food packaging material is required to have a high biocompatibility. The biocompatibility detection of the prepared three-layer coated paper is carried out by adopting an MTT colorimetric method, the result is shown in figure 9, the three-layer coated paper has no obvious influence on the cell metabolic activity, and the cell survival rates are respectively 98.22%, 96.37% and 93.58% when the concentrations of leaching liquor are respectively 0.5ug/mL, 1.0 ug/mL and 5.0 ug/mL. The morphology and proliferation status of the cells after contact with the leaching solution were observed by fluorescence images, and the results are shown in fig. 10, in which most of the cells are spindle-shaped and in a good stretched state. The surface three-layer coated paper has no cytotoxicity basically and has good biocompatibility as a food packaging material. The three layers of coatings are respectively chitosan, LCNFs and zein, and the three coatings are all natural high polymer materials and have good biocompatibility.

In conclusion, the food packaging paper prepared by the invention has good waterproof and oilproof effects, the three-layer coating paper can effectively inhibit the permeability of water vapor and oxygen, and the mechanical strength of the base paper after coating treatment can be obviously improved, and the barrier property is excellent. According to the invention, the zein is used as the outermost layer to be coated, so that good self-heat sealing capability can be provided for the food wrapping paper, the effect that the food wrapping paper can be used for packaging food without using an adhesive is realized, and meanwhile, the chitosan has good antibacterial performance, so that the food wrapping paper prepared by the method can inhibit the growth of bacteria in the food packaging process and the storage process, and the safety of the food is improved.

Claims

1. A preparation method of self-heating sealing antibacterial food packaging paper is characterized by comprising the following steps: sequentially coating the surface of base paper by using a chitosan solution and an LCNFs suspension, then drying and calendaring to obtain a double-layer coated sample, and coating the double-layer coated sample by using a zein solution to obtain a finished product.

2. The method of making self-sealing antimicrobial food wrapping paper of claim 1, wherein: the chitosan solution has a mass concentration of 0.2-3% and a coating weight of 0.1g/m ² -1.2g/m ² 。

3. The method of making self-sealing antimicrobial food wrapping paper of claim 2, wherein: the preparation of the chitosan solution is that chitosan is added into acetic acid solution with the volume fraction of 2 percent and stirred for 20-30h by a magnetic stirrer at the rotating speed of 100-250 rpm.

4. The method of making self-sealing antimicrobial food wrapping paper of claim 1, wherein: the concentration of the LCNFs suspension is 0.1-1.2 wt%, and the coating weight is 0.1g/m ² -1.2g/m ² 。

5. The method of making self-sealing antimicrobial food wrapping paper of claim 1, wherein: the LCNFs suspension is prepared by soaking a pulped plate in water for 20-30h, dispersing the pulp by using a tile power beater, adjusting the pulp concentration to 1.0-2 wt%, and grinding the pulp by using an ultrafine particle nano-mill: grinding the slurry for pretreatment, adjusting the disc grinding clearance to zero, wherein the rotating speed is 1000-1300rpm, and circularly grinding for 5-15 times under the condition of the disc grinding clearance of 0 mu m; then adjusting the disc grinding gap to-50 μm, increasing the rotation speed to 1400-1600rpm, and circularly grinding for 5-10 times; adjusting the rotating speed to 1800-2200rpm, circularly grinding for 5-15 times by a disc grinding clearance of-80 mu m, and finally circularly grinding for 30-50 times by a disc grinding clearance of-100 mu m to obtain a semi-finished product of the LCNFs suspension, adding a proper amount of deionized water into the semi-finished product of the LCNFs suspension for dilution, and dispersing by a high-shear disperser to finally obtain the LCNFs suspension with the concentration of 0.1-1.2 wt%.

6. The method of making self-sealing antimicrobial food wrapping paper of claim 1, wherein: the mass concentration of the zein solution is 2-10%, and the coating weight is 0.5g/m ² -6g/m ² 。

7. The method of making self-sealing antimicrobial food wrapping paper of claim 4, wherein: the zein solution is prepared by dissolving zein in an ethanol solution with the volume fraction of 85%, and stirring for 8-15h at the rotation speed of 400-600rpm by using a magnetic stirrer.

8. The method of making a self-sealing antimicrobial food wrapping paper of claim 1, wherein: the calendering temperature of the drying and calendering treatment is 100-200 ℃, and the pressure is 0.2-0.4 MPa.