A high-barrier single-PE composite packaging film for wet wipe packaging and its preparation process

Abstract

The present invention relates to the technical field of wet wipe packaging material research and development, and discloses a high-barrier single-PE composite packaging film for wet wipe packaging and a preparation process. The high-barrier single-PE composite packaging film is prepared by a high-speed solvent-free composite process from an outer layer of unidirectionally stretched polyethylene film, a middle layer of high-barrier polyethylene film, and an inner layer of unidirectionally stretched polyethylene film. The preparation method of the high-barrier polyethylene film includes: synthesizing a sulfonate-type anionic surfactant; under acidic conditions, using the sulfonate-type anionic surfactant as an intercalating agent to perform an organic modification treatment on sodium montmorillonite and disperse it in an ethylene-vinyl alcohol copolymer matrix to prepare an organic-inorganic composite barrier material; using PE resin as the sole raw material and the organic-inorganic composite barrier material as a functional modification reagent, and adopting a nine-layer co-extrusion blow molding process to prepare a high-barrier polyethylene film, which has excellent barrier properties and can be used as the middle layer material of a wet wipe composite packaging film.

Description

Technical Field

[0001] The present invention relates to the technical field of wet wipe packaging material research and development, and specifically to a high-barrier single-PE composite packaging film for wet wipe packaging and a preparation process thereof. Background Art

[0002] Wet wipe packaging bags are usually made by compounding polyethylene terephthalate (PET) with polyethylene (PE) or by compounding oriented polypropylene film (OPP) with polyethylene (PE). Different materials are not conducive to recycling.

[0003] MDOPE is a uniaxially stretched PE film, which has good rigidity, puncture resistance and heat resistance, and is widely used in fields such as food packaging, composite films, vertical liquid packaging bags, industrial packaging and multi-layer packaging films. When applied to packaging materials, it can achieve single-PE packaging, increase its recyclability, and the packaging film products have excellent machine-running performance, high-class appearance texture and good softness. However, the barrier property of polyethylene is not very satisfactory. Usually, multi-layer compounding and adding a barrier layer are required to meet the needs of packaging products. And the barrier property has always been an important index for wet wipe packaging materials, because the shelf life of wet wipe products is directly related to the barrier performance of the packaging material.

[0004] Montmorillonite has a unique natural layered nanostructure and has currently become a commonly used nanomaterial for improving the barrier performance of films. Due to the hydrophilicity of the montmorillonite surface, it is not conducive to its dispersion in the organic phase and wetting by the organic phase. To overcome this property, the ion exchangeability and adsorption property of montmorillonite can be utilized to make the surfactant (i.e., the intercalating agent) displace the inorganic cations between the montmorillonite layers, change the environment between the montmorillonite layers, make it change from hydrophilic to hydrophobic, reduce the surface energy of montmorillonite, and after modification, the interlayer spacing and specific surface area of montmorillonite increase, and the ability to adsorb organic matter is enhanced.

[0005] There are three types of surfactants that can be used for the preparation of organic montmorillonite: cationic, anionic and non-ionic. Currently, the preparation of cationic organic montmorillonite is relatively common. And research has found that: when the anionic surfactant sodium dodecyl sulfate is used as an organic intercalating agent for the modification treatment of montmorillonite, its effect is better than that of the currently commonly used cationic surfactant or organic amine treatment; and under acidic conditions, natural montmorillonite can adsorb strong acids, and the surface of the lamella has a very strong binding ability to H + and is more conducive to adsorbing anionic surfactants. Summary of the Invention

[0006] The present invention provides a high-barrier single-PE composite packaging film for wet wipes packaging, which is prepared by a high-speed solvent-free composite process from an outer layer of uniaxially stretched polyethylene film MDOPE, a middle layer of high-barrier polyethylene film, and an inner layer of uniaxially stretched polyethylene film MDOPE arranged in sequence. The independently developed high-barrier polyethylene film has the technical effect of significantly improving the barrier performance of the wet wipe composite packaging film, and this composite packaging film uses a single PE material, which is convenient for recycling and meets the environmental protection trend.

[0007] A preparation process of a high-barrier single-PE composite packaging film for wet wipes packaging comprises the following steps:

[0008] Step 1, set the product structure of the high-barrier single-PE composite packaging film for wet wipes packaging, and this product structure consists of an outer layer of uniaxially stretched polyethylene film MDOPE, a middle layer of high-barrier polyethylene film, and an inner layer of uniaxially stretched polyethylene film MDOPE;

[0009] Step 2, prepare the high-barrier polyethylene film, and its preparation method is as follows:

[0010] Step 1: Synthesize a disulfonate-type anionic surfactant or a trisulfonate-type anionic surfactant;

[0011] Step 2: Under acidic conditions, use the disulfonate-type anionic surfactant or the trisulfonate-type anionic surfactant as an intercalating agent to carry out organic modification treatment on sodium montmorillonite to prepare an anionic organic montmorillonite;

[0012] Step 3: Disperse the anionic organic montmorillonite in an ethylene-vinyl alcohol copolymer matrix to prepare an organic-inorganic composite barrier material;

[0013] Step 4: Using PE resin as the single raw material and the organic-inorganic composite barrier material as the functional modification reagent, design the film structure, the formulation and dosage of each film layer of a nine-layer coextruded film, and adopt a nine-layer coextrusion blow molding process to prepare the high-barrier polyethylene film;

[0014] Step 3, through a high-speed solvent-free composite process, composite the outer layer of uniaxially stretched polyethylene film MDOPE, the middle layer of high-barrier polyethylene film, and the inner layer of uniaxially stretched polyethylene film MDOPE to prepare a high-barrier single-PE composite packaging film for wet wipes packaging.

[0015] Preferably, the formulation and dosage of each film layer of the high-barrier polyethylene film are specifically as follows:

[0016] The first layer: The formulation is 100wt% low-density polyethylene resin LDPE, and the dosage is 5-15 parts by weight;

[0017] The second layer: The formulation is 100 wt% high-density polyethylene resin HDPE, and the dosage is 10 - 20 parts by weight;

[0018] The third layer: The formulation is 100 wt% low-density polyethylene resin LDPE, and the dosage is 5 - 15 parts by weight;

[0019] The fourth layer: The formulation is 100 wt% maleic anhydride grafted polyethylene resin PE-g-MAH, and the dosage is 3 - 10 parts by weight;

[0020] The fifth layer: The formulation is 85 - 95 wt% low-density polyethylene resin LDPE and 5 - 15 wt% organic-inorganic composite barrier material, and the dosage is 10 - 30 parts by weight;

[0021] The sixth layer: The formulation is 100 wt% maleic anhydride grafted polyethylene resin PE-g-MAH, and the dosage is 3 - 10 parts by weight;

[0022] The seventh layer: The formulation is 100 wt% low-density polyethylene resin LDPE, and the dosage is 5 - 15 parts by weight;

[0023] The eighth layer: The formulation is 100 wt% high-density polyethylene resin HDPE, and the dosage is 10 - 20 parts by weight;

[0024] The ninth layer: The formulation is 100 wt% low-density polyethylene resin LDPE, and the dosage is 5 - 15 parts by weight.

[0025] Preferably, the preparation method of the disulfonate anionic surfactant is as follows: 1 molar equivalent of N,N'-dimethyl-1,8-octanediamine undergoes a ring-opening reaction with 2.01 - 2.09 molar equivalents of 1,3-propane sultone, and is treated with sodium hydroxide to prepare the disulfonate anionic surfactant.

[0026] Preferably, the preparation method of the trisulfonate anionic surfactant is as follows:

[0027] 1 molar equivalent of 1-decylamine undergoes a ring-opening reaction with 1.01 - 1.09 molar equivalents of 1,3-propane sultone to generate a sulfonic acid group secondary amine monomer;

[0028] The chlorine functional group of 1 molar equivalent of cyanuric chloride undergoes a nucleophilic substitution reaction with the secondary amine functional group of 3.01 - 3.09 molar equivalents of the sulfonic acid group secondary amine monomer, and is treated with sodium carbonate to prepare the trisulfonate anionic surfactant.

[0029] Preferably, in step 2, an anionic organic montmorillonite is prepared under acidic conditions with pH ≤ 3.

[0030] Preferably, the mass ratio of the disulfonate-type anionic surfactant or trisulfonate-type anionic surfactant to sodium montmorillonite in the anionic organic montmorillonite is (0.01~0.1):1;

[0031] Preferably, the platelet diameter of the sodium montmorillonite is 2-5 μm and the thickness is 3-8 nm.

[0032] Preferably, the mass ratio of the anionic organic montmorillonite to ethylene-vinyl alcohol copolymer in the organic-inorganic composite barrier material is (0.05-0.5):1.

[0033] A high-barrier single-PE composite packaging film for wet wipe packaging prepared according to the above process is composed of a uniaxially stretched polyethylene film MDOPE layer with a thickness of 15-25 μm, a high-barrier polyethylene film layer with a thickness of 40-60 μm, and a uniaxially stretched polyethylene film MDOPE layer with a thickness of 15-25 μm.

[0034] Beneficial effects:

[0035] The present invention independently developed and synthesized a disulfonate-type anionic surfactant and a trisulfonate-type anionic surfactant;

[0036] Under acidic conditions, using the disulfonate-type anionic surfactant or trisulfonate-type anionic surfactant as an intercalating agent, the sodium montmorillonite is organically modified to obtain an anionic organic montmorillonite;

[0037] The anionic organic montmorillonite is dispersed in an ethylene-vinyl alcohol copolymer matrix to prepare an organic-inorganic composite barrier material;

[0038] Using the organic-inorganic composite barrier material to modify a single recyclable PE material, and adopting a nine-layer co-extrusion blow molding process to prepare a high-barrier polyethylene film with a water vapor transmission rate < 1.5 g / (m 2 •24 h), an oxygen transmission rate ≤ 1.0 cm 3 / (m 2 •24 h•0.1 MPa), and a tensile strength > 34 MPa. That is, the present invention provides a high-barrier polyethylene film with very excellent barrier performance, which can be used as an intermediate layer material for wet wipe composite packaging films. Description of the drawings

[0039] Figure 1 It is the performance test result of the high-barrier polyethylene film. Detailed implementation manners

[0040] The present invention uses montmorillonite nanosheets with excellent barrier performance and ethylene-vinyl alcohol copolymer as barrier modification raw materials for a single PE material;

[0041] The hydrophilic and oleophobic properties of inorganic montmorillonite are not conducive to its uniform dispersion in organic ethylene-vinyl alcohol copolymer. Therefore, in order to improve the compatibility between montmorillonite nanosheets and ethylene-vinyl alcohol copolymer, a sulfonate-type anionic surfactant was independently developed in this invention. The montmorillonite nanosheets were first subjected to an organic modification treatment using this new surfactant, and then compounded with ethylene-vinyl alcohol copolymer to obtain an organic-inorganic composite barrier material.

[0042] Experimental Example 1:

[0043] Preparation of disulfonate-type anionic surfactant: A ring-opening reaction occurred between 1 molar equivalent of N,N'-dimethyl-1,8-octanediamine and 2.05 molar equivalents of 1,3-propane sultone, and then a neutralization reaction occurred under the action of sodium hydroxide to generate a disulfonate-type anionic surfactant, whose chemical structural formula is:

[0044] ;

[0045] The specific experimental steps for preparing the disulfonate-type anionic surfactant are as follows: Add 2.5 g of 1,3-propane sultone and 30 mL of ethyl acetate into a three-necked flask, stir at room temperature until completely dissolved, then dropwise add 20 mL of an ethyl acetate solution containing 1.7 g of N,N'-dimethyl-1,8-octanediamine into the three-necked flask, stir and mix at room temperature for 30 min, raise the temperature to 65 °C and stir for 40 h, cool to room temperature, add 10 mL of a deionized water solution containing 0.5 g of sodium hydroxide, raise the temperature to 60 °C and stir for 5 h, filter, rotary evaporate to remove the solvent, perform recrystallization using a mixed solvent of methanol / acetone (the volume ratio of methanol to acetone is 3:2), and vacuum dry to obtain the disulfonate-type anionic surfactant;

[0046] The characterization result of the nuclear magnetic resonance hydrogen spectrum of the disulfonate-type anionic surfactant is as follows: 1 H NMR(CDCl 3 ₃, 400 MHz) δ: 1.31 - 1.40(m, 8H), 1.55 - 1.62(m, 4H), 1.75 - 1.82(m, 4H), 2.23(s, 6H), 2.29 - 2.32(t, 4H), 2.52 - 2.55(t, 4H), 2.81 - 2.85(t, 4H).

[0047] Experimental Example 2:

[0048] Preparation of trisulfonate-type anionic surfactant, and its preparation steps are as follows:

[0049] Step 1: A ring-opening reaction occurred between 1 molar equivalent of 1-decylamine and 1.04 molar equivalents of 1,3-propane sultone to generate a sulfonic acid group secondary amine monomer, whose chemical structural formula is:

[0050] ;

[0051] Step 2: A nucleophilic substitution reaction occurs between the chlorine functional groups of 1 mole equivalent of cyanuric chloride and the secondary amine functional groups of 3.02 mole equivalents of sulfonic acid group secondary amine monomers, and a neutralization reaction occurs under the action of sodium carbonate to produce a trisulfonate-type anionic surfactant, and its chemical structural formula is:

[0052] ;

[0053] The specific experimental steps for preparing the trisulfonate-type anionic surfactant are as follows:

[0054] Add 2.5 g of 1,3-propane sultone and 20 mL of ethanol to a three-necked flask, stir at room temperature until completely dissolved, then dropwise add 30 mL of an ethanol solution containing 3.1 g of 1-decylamine to the three-necked flask, stir and mix at room temperature for 30 min, raise the temperature to 65 °C and stir and react for 30 h, cool to room temperature, rotary evaporate to remove the solvent, wash with diethyl ether, recrystallize with a mixed solvent of methanol / acetone (the volume ratio of methanol to acetone is 3:2), and dry under vacuum to obtain the sulfonic acid group secondary amine monomer;

[0055] Add 0.9 g of cyanuric chloride, 4.2 g of sulfonic acid group secondary amine monomer, 1.7 g of sodium carbonate and 60 mL of methanol to a three-necked flask, stir at room temperature until completely dissolved, raise the temperature to 70 °C and stir and reflux for 12 h, cool to room temperature, rotary evaporate to remove the solvent, recrystallize with a mixed solvent of ethanol / acetone (the volume ratio of ethanol to acetone is 2:1), and dry under vacuum to obtain the trisulfonate-type anionic surfactant;

[0056] The characterization result of the nuclear magnetic resonance hydrogen spectrum of the trisulfonate-type anionic surfactant is as follows: 1 H NMR(CDCl 3 , 400 MHz) δ: 0.89 - 0.92 (t, 9H), 1.21 - 1.31 (m, 36H), 1.35 - 1.42 (m, 6H), 1.64 - 1.71 (m, 6H), 2.05 - 2.12 (m, 6H), 2.83 - 2.86 (t, 6H), 3.48 - 3.51 (t, 6H), 3.59 - 3.62 (t, 6H).

[0057] Experimental Example 3:

[0058] Preparation of anionic organic montmorillonite I: The preparation method is as follows. Under acidic conditions, using a disulfonate anionic surfactant as an intercalating agent, the sodium-based montmorillonite is organically modified to obtain anionic organic montmorillonite I. The specific experimental steps are as follows: Add 5 g of sodium-based montmorillonite (purchased from Jiangsu Xianfeng Nano Materials Technology Co., Ltd., with specifications: sheet diameter 2 - 5 μm, thickness 3 - 8 nm) into 200 mL of deionized water, ultrasonically disperse for 30 min, adjust the pH of the solution to 1 with 0.1 mol / L hydrochloric acid, stir and disperse at room temperature for 3 h, add 0.3 g of disulfonate anionic surfactant, raise the temperature to 60 °C and stir and react for 5 h, cool to room temperature, centrifuge and separate, wash successively with ethanol and deionized water, dry in vacuum, and grind to obtain anionic organic montmorillonite I;

[0059] Preparation of anionic organic montmorillonite II: The preparation method is as follows. Under acidic conditions, using a trisulfonate anionic surfactant as an intercalating agent, the sodium-based montmorillonite is organically modified to obtain anionic organic montmorillonite II. The difference in the specific experimental steps from those of anionic organic montmorillonite I is only that: the disulfonate anionic surfactant is replaced by a trisulfonate anionic surfactant;

[0060] Among them, under acidic conditions, the pH of the reaction system ≤ 3, and in this experimental example, the pH value of the reaction system is selected as 1.

[0061] Experimental Example Four:

[0062] Preparation of organic-inorganic composite barrier material I: The preparation method is as follows. Dispersing anionic organic montmorillonite I in an ethylene-vinyl alcohol copolymer matrix to obtain organic-inorganic composite barrier material I. The specific experimental steps are as follows: Add 10 g of ethylene-vinyl alcohol copolymer (purchased from Guangzhou Best New Materials Technology Co., Ltd., with the grade ET3803RB) and 1 g of anionic organic montmorillonite I into a high-speed mixer and mix evenly, and extrude and pelletize through a twin-screw extruder to obtain organic-inorganic composite barrier material I;

[0063] Among them, the process parameters of the twin-screw extruder are set as follows: the temperatures of zones 1 - 6 are 160 °C, 170 °C, 175 °C, 180 °C, 190 °C, 195 °C respectively, and the rotation speed is 300 r / min;

[0064] Preparation of organic-inorganic composite barrier material II: The preparation method is as follows. Dispersing anionic organic montmorillonite II in an ethylene-vinyl alcohol copolymer matrix to obtain organic-inorganic composite barrier material II. The difference in the specific experimental steps from those of organic-inorganic composite barrier material I is only that: anionic organic montmorillonite II is used to replace anionic organic montmorillonite I. Example One:

[0065] A high-barrier single-PE composite packaging film for wet wipe packaging, and its product structure is the following layers arranged in sequence: a uniaxially stretched polyethylene film MDOPE layer, a high-barrier polyethylene film layer, and a uniaxially stretched polyethylene film MDOPE layer;

[0066] The high-barrier single-PE composite packaging film for wet wipe packaging is prepared by compounding a uniaxially stretched polyethylene film MDOPE layer with a thickness of 20 μm, a high-barrier polyethylene film layer with a thickness of 50 μm, and a uniaxially stretched polyethylene film MDOPE layer with a thickness of 20 μm through a high-speed solventless compounding process;

[0067] Among them, the uniaxially stretched polyethylene film MDOPE used in the uniaxially stretched polyethylene film MDOPE layer is purchased from Guangdong Color Dragon New Materials Co., Ltd.; the high-barrier polyethylene film used in the high-barrier polyethylene film layer is co-extruded from the first layer, the second layer, the third layer, the fourth layer, the fifth layer, the sixth layer, the seventh layer, the eighth layer, and the ninth layer arranged in sequence. Example 2:

[0068] Prepare a high-barrier polyethylene film: Design the film structure, the formula and dosage of each film layer (the specific content is shown in Table 1 below), use a nine-layer co-extrusion film blowing machine set, and control the blow-up ratio at 2.6 to prepare a high-barrier polyethylene film with a thickness of 50 μm;

[0069] Table 1 Experimental formula and process parameters of high-barrier polyethylene film

[0070]

[0071] When the organic-inorganic composite barrier material uses organic-inorganic composite barrier materials I and II respectively, high-barrier polyethylene films I and II are prepared correspondingly;

[0072] When using the organic-inorganic blend barrier material MMT / EVOH to replace the organic-inorganic composite barrier material, polyethylene film a is prepared, which is used as Comparative Example 1;

[0073] Among them, the preparation method of the organic-inorganic blend barrier material MMT / EVOH is: directly mix sodium-based montmorillonite with an ethylene-vinyl alcohol copolymer matrix to prepare the organic-inorganic blend barrier material MMT / EVOH. The difference in the specific experimental steps from those of organic-inorganic composite barrier material I is only that: sodium-based montmorillonite is used to replace anionic organic montmorillonite I;

[0074] When using ethylene-vinyl alcohol copolymer to replace the organic-inorganic composite barrier material, polyethylene film b is prepared, which is used as Comparative Example 2;

[0075] When the organic-inorganic composite barrier material is not used (i.e., the raw material formula of the fifth layer is 100 wt% low-density polyethylene resin LDPE), polyethylene film c is prepared, which is used as Comparative Example 3.

[0076] Performance test:

[0077] I. Barrier performance test:

[0078] (1) Use the TC-03 type water vapor transmission rate tester to test the water barrier performance of the sample according to GB / T 1037-2021, and record the water vapor transmission rate of the sample;

[0079] (2) Use the Y110 type oxygen transmission rate tester to test the oxygen barrier performance of the sample according to GB / T 1038-2022, and record the oxygen transmission rate of the sample;

[0080] II. Mechanical properties:

[0081] Use the Instron 5565 universal tensile testing machine to test the mechanical properties of the sample according to GB / T 1040.1-2018, record the longitudinal tensile strength of the sample, the sample size is 150 mm × 20 mm (sampled along the blown film direction), and the tensile rate is 5 mm / min;

[0082] The above experimental results are shown in Table 2 below and Figure 1 .

[0083] Table 2 Experimental results of the performance of the high-barrier polyethylene film in the high-barrier single-PE composite packaging film for wet wipe packaging

[0084]

[0085] Through comprehensive analysis of the above experimental results, the following conclusions can be drawn:

[0086] By using the organic-inorganic composite barrier materials I and II to modify the single recyclable PE material, the high-barrier polyethylene film thus prepared has achieved beneficial technical effects of significant improvement in both barrier performance and mechanical properties compared with the prior art;

[0087] Among them, the organic-inorganic composite barrier material II obtained by compounding montmorillonite modified by a trisulfonate-type anionic surfactant with ethylene-vinyl alcohol copolymer has more excellent dispersibility, swelling property and thixotropy, so its modification effect on polyethylene resin will be more significant, and the experimental results fully confirm this conclusion.

Claims

1. A preparation process of a high-barrier single PE composite packaging film for wet wipes packaging, characterized in that: The following steps are involved: Step 1, setting a product structure of a high-barrier single PE composite packaging film for wet wipes packaging, the product structure consisting of an outer layer uniaxially oriented polyethylene film MDOPE, a middle layer high-barrier polyethylene film and an inner layer uniaxially oriented polyethylene film MDOPE; Step 2: prepare a high barrier polyethylene film, the preparation method of which is as follows: Step 1: synthesizing a disulfonate type anionic surfactant or a trisulfonate type anionic surfactant; Step 2: Under acidic conditions, using a disulfonate type anionic surfactant or a trisulfonate type anionic surfactant as an intercalating agent, the sodium-based montmorillonite is subjected to organic modification treatment to prepare anionic organic montmorillonite; Step 3: dispersing anionic organic montmorillonite in an ethylene-vinyl alcohol copolymer matrix to prepare an organic-inorganic composite barrier material; Step 4: Using PE resin as a single raw material and an organic-inorganic composite barrier material as a functional modification agent, designing the film structure of the nine-layer co-extrusion film, the formula and dosage of each film layer, and adopting a nine-layer co-extrusion blow molding film forming process to prepare a high barrier polyethylene film; Step three, compounding the outer layer uniaxially stretched polyethylene film MDOPE, the middle layer high barrier polyethylene film and the inner layer uniaxially stretched polyethylene film MDOPE through a high-speed solvent-free compounding process to prepare a high barrier single PE composite packaging film for wet wipes packaging.

2. The preparation process of a high barrier single PE composite packaging film for wet wipes packaging according to claim 1, characterized in that: The formula and dosage of each film layer of the high barrier polyethylene film are as follows: First layer: the formula is 100wt% low-density polyethylene resin LDPE, the amount is 5-15 parts by weight; The second layer: the formula is 100wt% high-density polyethylene resin HDPE, the amount is 10-20 parts by weight; The third layer: the formula is 100wt% low-density polyethylene resin LDPE, the amount is 5-15 parts by weight; The fourth layer: the formula is 100wt% maleic anhydride grafted polyethylene resin PE-g-MAH, the amount is 3-10 parts by weight; The fifth layer: the formula is 85-95wt% low-density polyethylene resin LDPE and 5-15wt% organic-inorganic composite barrier material, the amount is 10-30 parts by weight; The sixth layer: the formula is 100wt% maleic anhydride grafted polyethylene resin PE-g-MAH, the amount is 3-10 parts by weight; The seventh layer: the formula is 100wt% low-density polyethylene resin LDPE, the amount is 5-15 parts by weight; The eighth layer: the formula is 100wt% high-density polyethylene resin HDPE, the amount is 10-20 parts by weight; Ninth layer: The formula is 100wt% low-density polyethylene resin LDPE, and the amount used is 5-15 parts by weight.

3. The preparation process of a high barrier single PE composite packaging film for wet wipes packaging according to claim 1, characterized in that: The chemical structural formula of the disulfonate type anionic surfactant is: 。 4. The preparation process of a high barrier single PE composite packaging film for wet wipes packaging according to claim 3, characterized in that: The preparation method of the disulfonate type anionic surfactant is as follows: 1 molar equivalent of N,N'-dimethyl-1,8-octanediamine and 2.01-2.09 molar equivalents of 1,3-propane sultone undergo a ring-opening reaction, and the reaction is treated with sodium hydroxide to prepare the disulfonate type anionic surfactant.

5. The preparation process of a high barrier single PE composite packaging film for wet wipes packaging according to claim 1, characterized in that: The chemical structural formula of the trisulfonate type anionic surfactant is: 。 6. The process for preparing a high barrier single PE composite packaging film for wet wipes packaging according to claim 5, characterized in that: The preparation method of the trisulfonate type anionic surfactant is as follows: A sulfonic acid secondary amine monomer is generated by a ring-opening reaction of 1 molar equivalent of 1-decylamine and 1.01-1.09 molar equivalent of 1,3-propane sultone; The trisulfonate type anionic surfactant is prepared by a nucleophilic substitution reaction between the chlorine functional group of 1 molar equivalent of cyanuric chloride and the secondary amine functional group of 3.01-3.09 molar equivalents of sulfonic acid secondary amine monomers, and then treated with sodium carbonate.

7. The process for preparing a high barrier single PE composite packaging film for wet wipes packaging according to claim 1, characterized in that: The step 2: preparing anionic organic montmorillonite under acidic conditions of pH ≤ 3.

8. The process for preparing a high barrier single PE composite packaging film for wet wipes packaging according to claim 1, characterized in that: The mass ratio of the disulfonate anionic surfactant or trisulfonate anionic surfactant to the sodium-based montmorillonite in the anionic organic montmorillonite is (0.01-0.1):1; The sodium montmorillonite has a sheet diameter of 2-5 μm and a thickness of 3-8 nm.

9. The process for preparing a high barrier single PE composite packaging film for wet wipes packaging according to claim 1, characterized in that: The mass ratio of anionic organic montmorillonite to ethylene-vinyl alcohol copolymer in the organic-inorganic composite barrier material is (0.05-0.5):

1.

10. A high barrier single PE composite packaging film for wet wipes packaging prepared by the process according to any one of claims 1 to 9, characterized in that: The high barrier single PE composite packaging film consists of a uniaxially stretched polyethylene film MDOPE layer with a thickness of 15-25 μm, a high barrier polyethylene film layer with a thickness of 40-60 μm and a uniaxially stretched polyethylene film MDOPE layer with a thickness of 15-25 μm.

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