Preparation method of polyethylene wrapping film

Abstract

A preparation method of a polyethylene wrapping film belongs to the field of polyethylene wrapping film preparation, and comprises the following steps: step 1, preparing a first nanoscale polyethylene emulsion; step 2, preparing a second nanoscale polyethylene emulsion; 3, preparing a mixed emulsion; step 4, adding a demulsifier into the mixed emulsion obtained in the step 3, carrying out demulsification operation, filtering, cleaning and drying to obtain mixed particles; and 5, carrying out hot melting on the mixed particles obtained in the step 4, and carrying out film making operation through a casting machine to obtain the polyethylene wrapping film. The composite polyethylene particles are obtained through three times of emulsion preparation, and the polyethylene wrapping film is prepared, so that the high temperature resistance of the polyethylene wrapping film can be improved; meanwhile, the nano-scale hydroxylated calcium carbonate is added, so that the high-temperature resistance of the polyethylene wrapping film can be further improved.

Description

Technical Field

[0001] The invention belongs to the field of polyethylene stretch film preparation, in particular to a method for preparing a polyethylene stretch film. Background Art

[0002] Polyethylene stretch film (PE stretch film) is a common stretch film today. Compared to traditional polyvinyl chloride stretch film (PVC stretch film), its advantages are as follows: First, PE stretch film has a low production cost and a high cost-effectiveness ratio. It is thin, wraps beautiful objects, and is waterproof and dustproof, making it suitable for industries such as logistics, machinery, and electronics. Second, PE stretch film exhibits excellent mechanical properties and stability. PE stretch film is more mechanically stable, and its transverse and longitudinal elongation rates are greater than those of PVC stretch film, making it suitable for large-scale packaging and long-distance transportation. Third, PE stretch film has good transparency and uniform thickness, ensuring ease of use and effectiveness. PVC stretch film has poor transparency and a pale yellow color. However, polyethylene stretch film also has poor high-temperature resistance, which limits its use. Summary of the Invention

[0003] The present invention provides a method for preparing a polyethylene stretch film, which is used to solve the defects in the prior art.

[0004] The present invention is achieved through the following technical solutions:

[0005] A method for preparing a polyethylene stretch film comprises the following steps:

[0006] Step 1: mixing nano-scale polyethylene, tri-n-decyl trimellitate, acetyl tributyl citrate, glyceryl monooleate, 2,5-dimethyl-2,5-di-tert-butyl peroxide, polyvinyl pyrrolidone, ethylenediamine, trisnonylphenyl phosphite and deionized water, and reacting the mixture to obtain a first nano-scale polyethylene emulsion;

[0007] Step 2: mixing the first nano-scale polyethylene emulsion obtained in step 1, methyl ethylene oxide, nano-scale N-tert-butylbis-2-benzothiazole sulfenamide, nano-scale N,N'-p-phenyl bismaleimide, nano-scale cyclohexanone peroxide, triallyl isocyanurate and fatty alcohol polyoxyethylene ether, and reacting the mixture to obtain a second nano-scale polyethylene emulsion;

[0008] Step 3: mixing the second nano-scale polyethylene emulsion obtained in step 2, dibenzoylquinone dioxime, nano-scale hydroxylated calcium carbonate, sodium ethylenediaminetetramethylenephosphonate, tris(4-allyl-2-hydroxyphenyl)phosphate, hexabromocyclododecane, sodium 2-methyl-1-oxydodecylaminoethanesulfonate and deionized water, and reacting the mixture to obtain a mixed emulsion after the reaction is completed;

[0009] Step 4: adding a demulsifier to the mixed emulsion obtained in step 3 to perform a demulsification operation, filtering, washing, and drying to obtain mixed particles;

[0010] Step 5: hot-melt the mixed particles obtained in step 4 and then use a casting machine to perform a film-making operation to obtain a polyethylene stretch film.

[0011] In the above-mentioned method for preparing a polyethylene stretch film, the molecular weight of the nano-polyethylene in step 1 is 400,000-500,000.

[0012] According to the above-mentioned method for preparing a polyethylene stretch film, in step 1, the mass ratio of nano-scale polyethylene, tri-n-decyl trimellitate, acetyl tributyl citrate, glyceryl monooleate, 2,5-dimethyl-2,5-di-tert-butyl peroxide, polyvinyl pyrrolidone, ethylenediamine, trisnonylphenyl phosphite and deionized water is 300-330:30-50:20-30:10-20:10-20:3-6:4-8:20-30:200-220.

[0013] In the above-mentioned method for preparing a polyethylene stretch film, the reaction temperature in step 1 is 110-120° C., the reaction is carried out in a sealed manner, an inert gas is introduced for protection during the reaction, the reaction stirring speed is 300-400 r / min, and the reaction time is 6-8 h.

[0014] In the above-mentioned method for preparing a polyethylene stretch film, the mass ratio of the first nano-scale polyethylene emulsion, methyl ethylene oxide, nano-scale N-tert-butylbis-2-benzothiazole sulfenamide, nano-scale N,N'-p-phenylbismaleimide, nano-scale cyclohexanone peroxide, triallyl isocyanurate and fatty alcohol polyoxyethylene ether in the step 2 is: 400-500: 30-40: 10-20: 10-20: 6-8: 6-10: 4-6.

[0015] In the above-mentioned method for preparing a polyethylene stretch film, the reaction temperature in step 2 is 120-130° C., the reaction is carried out in a sealed manner, an inert gas is introduced for protection during the reaction, the reaction stirring speed is 350-450 r / min, and the reaction time is 4-6 h.

[0016] According to the method for preparing a polyethylene stretch film as described above, the mass ratio of the second nano-scale polyethylene emulsion, dibenzoylquinone dioxime, nano-scale hydroxylated calcium carbonate, sodium ethylenediaminetetramethylenephosphonate, tris(4-allyl-2-hydroxyphenyl)phosphate, hexabromocyclododecane, sodium 2-methyl-1-oxydodecylaminoethanesulfonate and deionized water in step three is: 300-400: 20-30: 60-80: 6-10: 10-20: 6-10: 6-10: 100-120.

[0017] In the above-mentioned method for preparing a polyethylene stretch film, the reaction temperature in step three is 90-100° C., the reaction is carried out in a sealed manner, an inert gas is introduced for protection during the reaction, the reaction stirring speed is 200-300 r / min, and the reaction time is 8-10 h.

[0018] According to the above-mentioned method for preparing a polyethylene stretch film, the demulsifier in the step 4 is a PE2040 type demulsifier, and the amount of the demulsifier added is 1-2 g / kg. After the demulsifier is added, the temperature is raised to 60-70°C at a stirring speed of 800-900 r / min, and the mixture is kept warm and stirred for 50-60 minutes, then cooled to room temperature and filtered. After the filtration is completed, the mixture is washed with deionized water 3-5 times and then dried at a temperature of 60-70°C for 30-40 minutes.

[0019] In the above-mentioned method for preparing a polyethylene stretch film, the thickness of the film obtained in step five is 0.2 mm.

[0020] The advantages of the present invention are: the composite polyethylene particles are obtained by preparing the tertiary emulsion and are prepared into a polyethylene stretch film, thereby improving the high temperature resistance of the polyethylene stretch film; and at the same time, the addition of nano-scale hydroxylated calcium carbonate can further improve the high temperature resistance of the polyethylene stretch film. DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0022] Example 1

[0023] Step 1: nano-scale polyethylene (molecular weight of 400,000-500,000), tridecyl trimellitate, acetyl tributyl citrate, monoolein, 2,5-dimethyl-2,5-di-tert-butyl peroxide, polyvinyl pyrrolidone, ethylenediamine, trisnonylphenyl phosphite and deionized water are mixed and reacted at a reaction temperature of 110° C. The reaction is carried out in a sealed container. During the reaction, an inert gas is introduced for protection. The reaction stirring speed is 300 r / min and the reaction time is 8 hours. After the reaction is completed, a first nano-scale polyethylene emulsion is obtained.

[0024] The mass ratio of nano-sized polyethylene (molecular weight of 400,000-500,000), tridecyl trimellitate, acetyl tributyl citrate, glyceryl monooleate, 2,5-dimethyl-2,5-di-tert-butyl peroxide, polyvinyl pyrrolidone, ethylenediamine, trisnonylphenyl phosphite and deionized water is 300:30:20:10:10:3:4:20:200.

[0025] Step 2: The first nano-scale polyethylene emulsion obtained in step 1, methyl ethylene oxide, nano-scale N-tert-butylbis-2-benzothiazole sulfenamide, nano-scale N,N'-p-phenyl bismaleimide, nano-scale cyclohexanone peroxide, triallyl isocyanurate and fatty alcohol polyoxyethylene ether are mixed and reacted at a reaction temperature of 120° C. The reaction is carried out in a sealed manner, an inert gas is introduced for protection during the reaction, the reaction stirring speed is 350 r / min, the reaction time is 4 hours, and after the reaction is completed, a second nano-scale polyethylene emulsion is obtained;

[0026] The mass ratio of the first nano-scale polyethylene emulsion, methyl ethylene oxide, nano-scale N-tert-butylbis-2-benzothiazole sulfenamide, nano-scale N,N'-p-phenyl bismaleimide, nano-scale cyclohexanone peroxide, triallyl isocyanurate and fatty alcohol polyoxyethylene ether is: 400:30:10:10:6:6:4;

[0027] Step 3: The second nano-scale polyethylene emulsion obtained in step 2, dibenzoylquinone dioxime, nano-scale hydroxylated calcium carbonate, sodium ethylenediaminetetramethylenephosphonate, tris(4-allyl-2-hydroxyphenyl)phosphate, hexabromocyclododecane, sodium 2-methyl-1-oxydodecylaminoethanesulfonate and deionized water are mixed and reacted at a reaction temperature of 90° C. The reaction is sealed and an inert gas is introduced during the reaction for protection. The reaction stirring speed is 200 r / min and the reaction time is 8 h. After the reaction is completed, a mixed emulsion is obtained;

[0028] The mass ratio of the second nano-scale polyethylene emulsion, dibenzoylquinone dioxime, nano-scale hydroxylated calcium carbonate, sodium ethylenediaminetetramethylenephosphonate, tris(4-allyl-2-hydroxyphenyl)phosphate, hexabromocyclododecane, sodium 2-methyl-1-oxydodecylaminoethanesulfonate and deionized water is: 300:20:60:6:10:6:6:100;

[0029] Step 4: adding a demulsifier to the mixed emulsion obtained in step 3 for demulsification, wherein the demulsifier is a PE2040 type demulsifier, and the amount of the demulsifier added is 1 g / kg. After the demulsifier is added, the mixture is heated to 60° C. at a stirring speed of 800 r / min, kept stirred for 60 minutes, and then cooled to room temperature and filtered. After the filtration is completed, the mixture is washed with deionized water three times, and then dried at a temperature of 60° C. for 40 minutes to obtain mixed particles;

[0030] Step 5: The mixed particles obtained in step 4 are hot-melted and then subjected to a film-making operation using a casting machine to obtain a polyethylene stretch film with a thickness of 0.2 mm.

[0031] Example 2

[0032] Step 1: nano-scale polyethylene (molecular weight of 400,000-500,000), tridecyl trimellitate, acetyl tributyl citrate, glyceryl monooleate, 2,5-dimethyl-2,5-di-tert-butyl peroxide, polyvinyl pyrrolidone, ethylenediamine, trisnonylphenyl phosphite and deionized water are mixed and reacted at a reaction temperature of 120° C. The reaction is carried out in a sealed state. During the reaction, an inert gas is introduced for protection. The reaction stirring speed is 400 r / min and the reaction time is 6 hours. After the reaction is completed, a first nano-scale polyethylene emulsion is obtained.

[0033] The mass ratio of nano-sized polyethylene (molecular weight 400,000-500,000), tridecyl trimellitate, acetyl tributyl citrate, glyceryl monooleate, 2,5-dimethyl-2,5-di-tert-butyl peroxide, polyvinyl pyrrolidone, ethylenediamine, trisnonylphenyl phosphite and deionized water is 330:50:30:20:20:6:8:30:220;

[0034] Step 2: The first nano-scale polyethylene emulsion obtained in step 1, methyl ethylene oxide, nano-scale N-tert-butylbis-2-benzothiazole sulfenamide, nano-scale N,N'-p-phenyl bismaleimide, nano-scale cyclohexanone peroxide, triallyl isocyanurate and fatty alcohol polyoxyethylene ether are mixed and reacted at a reaction temperature of 130° C. The reaction is carried out in a sealed manner, an inert gas is introduced for protection during the reaction, the reaction stirring speed is 450 r / min, the reaction time is 4 hours, and after the reaction is completed, a second nano-scale polyethylene emulsion is obtained;

[0035] The mass ratio of the first nano-scale polyethylene emulsion, methyl ethylene oxide, nano-scale N-tert-butylbis-2-benzothiazole sulfenamide, nano-scale N,N'-p-phenyl bismaleimide, nano-scale cyclohexanone peroxide, triallyl isocyanurate and fatty alcohol polyoxyethylene ether is 500:40:20:20:8:10:6;

[0036] Step 3: The second nano-scale polyethylene emulsion obtained in step 2, dibenzoylquinone dioxime, nano-scale hydroxylated calcium carbonate, sodium ethylenediaminetetramethylenephosphonate, tris(4-allyl-2-hydroxyphenyl)phosphate, hexabromocyclododecane, sodium 2-methyl-1-oxydodecylaminoethanesulfonate and deionized water are mixed and reacted at a reaction temperature of 100° C. The reaction is sealed and an inert gas is introduced during the reaction for protection. The reaction stirring speed is 300 r / min and the reaction time is 8 h. After the reaction is completed, a mixed emulsion is obtained;

[0037] The mass ratio of the second nano-scale polyethylene emulsion, dibenzoylquinone dioxime, nano-scale hydroxylated calcium carbonate, sodium ethylenediaminetetramethylenephosphonate, tris(4-allyl-2-hydroxyphenyl)phosphate, hexabromocyclododecane, sodium 2-methyl-1-oxydodecylaminoethanesulfonate and deionized water is 400:30:80:10:20:10:10:120.

[0038] Step 4: adding a demulsifier to the mixed emulsion obtained in step 3 for demulsification, wherein the demulsifier is a PE2040 type demulsifier, and the amount of the demulsifier added is 2 g / kg. After the demulsifier is added, the mixture is heated to 70° C. at a stirring speed of 900 r / min, kept stirred for 50 minutes, and then cooled to room temperature and filtered. After the filtration is completed, the mixture is washed with deionized water 5 times, and then dried at 70° C. for 30 minutes to obtain mixed particles;

[0039] Step 5: The mixed particles obtained in step 4 are hot-melted and then subjected to a film-making operation using a casting machine to obtain a polyethylene stretch film with a thickness of 0.2 mm.

[0040] Example 3

[0041] Step 1: nano-scale polyethylene (molecular weight of 400,000-500,000), tridecyl trimellitate, acetyl tributyl citrate, monoolein, 2,5-dimethyl-2,5-di-tert-butyl peroxide, polyvinyl pyrrolidone, ethylenediamine, trisnonylphenyl phosphite and deionized water are mixed and reacted at a reaction temperature of 115° C. The reaction is sealed and an inert gas is introduced during the reaction for protection. The reaction stirring speed is 350 r / min and the reaction time is 7 hours. After the reaction is completed, a first nano-scale polyethylene emulsion is obtained;

[0042] The mass ratio of nano-sized polyethylene (molecular weight 400,000-500,000), tridecyl trimellitate, acetyl tributyl citrate, glyceryl monooleate, 2,5-dimethyl-2,5-di-tert-butyl peroxide, polyvinyl pyrrolidone, ethylenediamine, trisnonylphenyl phosphite and deionized water is 315:40:25:15:15:5:6:25:210;

[0043] Step 2: The first nano-scale polyethylene emulsion obtained in step 1, methyl ethylene oxide, nano-scale N-tert-butylbis-2-benzothiazole sulfenamide, nano-scale N,N'-p-phenyl bismaleimide, nano-scale cyclohexanone peroxide, triallyl isocyanurate and fatty alcohol polyoxyethylene ether are mixed and reacted at a reaction temperature of 125° C. The reaction is carried out in a sealed manner, an inert gas is introduced for protection during the reaction, the reaction stirring speed is 400 r / min, the reaction time is 5 hours, and after the reaction is completed, a second nano-scale polyethylene emulsion is obtained;

[0044] The mass ratio of the first nano-scale polyethylene emulsion, methyl ethylene oxide, nano-scale N-tert-butylbis-2-benzothiazole sulfenamide, nano-scale N,N'-p-phenyl bismaleimide, nano-scale cyclohexanone peroxide, triallyl isocyanurate and fatty alcohol polyoxyethylene ether is: 450:35:15:15:7:8:5;

[0045] Step 3: The second nano-scale polyethylene emulsion obtained in step 2, dibenzoylquinone dioxime, nano-scale hydroxylated calcium carbonate, sodium ethylenediaminetetramethylenephosphonate, tris(4-allyl-2-hydroxyphenyl)phosphate, hexabromocyclododecane, sodium 2-methyl-1-oxydodecylaminoethanesulfonate and deionized water are mixed and reacted at a reaction temperature of 95° C. The reaction is sealed and an inert gas is introduced during the reaction for protection. The reaction stirring speed is 250 r / min and the reaction time is 9 hours. After the reaction is completed, a mixed emulsion is obtained;

[0046] The mass ratio of the second nano-scale polyethylene emulsion, dibenzoylquinone dioxime, nano-scale hydroxylated calcium carbonate, sodium ethylenediaminetetramethylenephosphonate, tris(4-allyl-2-hydroxyphenyl)phosphate, hexabromocyclododecane, sodium 2-methyl-1-oxydodecylaminoethanesulfonate and deionized water is 350:25:70:8:15:8:8:110.

[0047] Step 4: adding a demulsifier to the mixed emulsion obtained in step 3 for demulsification, wherein the demulsifier is a PE2040 type demulsifier, and the amount of the demulsifier added is 1.5 g / kg. After the demulsifier is added, the mixture is heated to 65° C. at a stirring speed of 850 r / min, kept stirred for 55 minutes, and then cooled to room temperature and filtered. After the filtration is completed, the mixture is washed with deionized water 4 times, and then dried at a temperature of 65° C. for 35 minutes to obtain mixed particles;

[0048] Step 5: The mixed particles obtained in step 4 are hot-melted and then subjected to a film-making operation using a casting machine to obtain a polyethylene stretch film with a thickness of 0.2 mm.

[0049] The polyethylene stretch films prepared in Examples 1-3 were compared with commercially available polyethylene stretch films (referred to as comparative examples). A portion of the same polyethylene stretch film samples from Examples 1-3 and the comparative example was first tested for tensile strength, yield strength, and elongation (using the corresponding testing methods in accordance with national standard GB / T 1040.1-2006). The remaining polyethylene stretch film samples from Examples 1-3 and the comparative example were then placed at 80°C for 2 hours and then resampled for tensile strength, yield strength, and elongation. The results are shown in Table 1.

[0050]

[0051]

[0052] Table 1

[0053] As can be seen from the data in Table 1, the polyethylene stretch films prepared in Examples 1-3 of the present invention have better performance than the polyethylene stretch films of the comparative example before high-temperature treatment. After high-temperature treatment, the performance of the polyethylene stretch films prepared in Examples 1-3 of the present invention decreases slightly, while the performance of the polyethylene stretch film of the comparative example decreases significantly after high-temperature treatment. Therefore, the polyethylene stretch films prepared in the present invention have good high-temperature resistance and can be used stably for a long time in a high-temperature environment.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for preparing a polyethylene stretch film, characterized in that: The steps include: Step 1: mixing nano-scale polyethylene, tri-n-decyl trimellitate, acetyl tributyl citrate, glyceryl monooleate, 2,5-dimethyl-2,5-di-tert-butyl peroxide, polyvinyl pyrrolidone, ethylenediamine, trisnonylphenyl phosphite and deionized water, and reacting the mixture to obtain a first nano-scale polyethylene emulsion; Step 2: mixing the first nano-scale polyethylene emulsion obtained in step 1, methyl ethylene oxide, nano-scale N-tert-butylbis-2-benzothiazole sulfenamide, nano-scale N,N'-p-phenyl bismaleimide, nano-scale cyclohexanone peroxide, triallyl isocyanurate and fatty alcohol polyoxyethylene ether, and reacting the mixture to obtain a second nano-scale polyethylene emulsion; Step 3: mixing the second nano-scale polyethylene emulsion obtained in step 2, dibenzoylquinone dioxime, nano-scale hydroxylated calcium carbonate, sodium ethylenediaminetetramethylenephosphonate, tris(4-allyl-2-hydroxyphenyl)phosphate, hexabromocyclododecane, sodium 2-methyl-1-oxydodecylaminoethanesulfonate and deionized water, and reacting the mixture to obtain a mixed emulsion after the reaction is completed; Step 4: adding a demulsifier to the mixed emulsion obtained in step 3 to perform a demulsification operation, filtering, washing, and drying to obtain mixed particles; Step 5: hot-melt the mixed particles obtained in step 4 and then use a casting machine to perform a film-making operation to obtain a polyethylene stretch film.

2. The method for preparing a polyethylene stretch film according to claim 1, wherein: The molecular weight of the nano-scale polyethylene in step 1 is 400,000-500,000.

3. The method for preparing a polyethylene stretch film according to claim 1, wherein: In the step 1, the mass ratio of nano-scale polyethylene, tridecyl trimellitate, acetyl tributyl citrate, glyceryl monooleate, 2,5-dimethyl-2,5-di-tert-butyl peroxide, polyvinyl pyrrolidone, ethylenediamine, trisnonylphenyl phosphite and deionized water is 300-330:30-50:20-30:10-20:10-20:3-6:4-8:20-30:200-220.

4. The method for preparing a polyethylene stretch film according to claim 1, wherein: The reaction temperature in step 1 is 110-120° C., the reaction is carried out in a sealed manner, an inert gas is introduced during the reaction for protection, the reaction stirring speed is 300-400 r / min, and the reaction time is 6-8 h.

5. The method for preparing a polyethylene stretch film according to claim 1, wherein: The mass ratio of the first nano-scale polyethylene emulsion, methyl ethylene oxide, nano-scale N-tert-butylbis-2-benzothiazole sulfenamide, nano-scale N,N'-p-phenyl bismaleimide, nano-scale cyclohexanone peroxide, triallyl isocyanurate and fatty alcohol polyoxyethylene ether in the step 2 is: 400-500: 30-40: 10-20: 10-20: 6-8: 6-10: 4-6.

6. The method for preparing a polyethylene stretch film according to claim 1, wherein: The reaction temperature in the step 2 is 120-130° C., the reaction is carried out in a sealed manner, an inert gas is introduced during the reaction for protection, the reaction stirring speed is 350-450 r / min, and the reaction time is 4-6 h.

7. The method for preparing a polyethylene stretch film according to claim 1, wherein: The mass ratio of the second nano-scale polyethylene emulsion, dibenzoylquinone dioxime, nano-scale hydroxylated calcium carbonate, sodium ethylenediaminetetramethylenephosphonate, tris(4-allyl-2-hydroxyphenyl)phosphate, hexabromocyclododecane, sodium 2-methyl-1-oxydodecylaminoethanesulfonate and deionized water in the step three is: 300-400: 20-30: 60-80: 6-10: 10-20: 6-10: 6-10: 100-120.

8. The method for preparing a polyethylene stretch film according to claim 1, wherein: In the step 3, the reaction temperature is 90-100° C., the reaction is carried out in a sealed container, an inert gas is introduced for protection during the reaction, the reaction stirring speed is 200-300 r / min, and the reaction time is 8-10 h.

9. The method for preparing a polyethylene stretch film according to claim 1, wherein: The demulsifier in the step 4 is a PE2040 type demulsifier, and the amount of the demulsifier added is 1-2 g / kg. After the demulsifier is added, the temperature is raised to 60-70°C at a stirring speed of 800-900 r / min, and the mixture is kept warm and stirred for 50-60 minutes. Then, the mixture is cooled to room temperature and filtered. After filtration, the mixture is washed with deionized water 3-5 times and then dried at a temperature of 60-70°C for 30-40 minutes.

10. The method for preparing a polyethylene stretch film according to claim 1, wherein: The film thickness obtained in step 5 is 0.2 mm.

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