A polyethylene aluminum-coated film composition, film, preparation method and application

Abstract

This invention belongs to the field of composite film preparation technology, and provides a polyethylene aluminized film composition, film, preparation method, and application. The invention first prepares a hydroxyl-containing acrylate copolymer, then reacts it with an ethylene-based random terpolymer and extrudes it to obtain a vinyl phosphate anchoring resin. This resin is then compounded with metallocene linear low-density polyethylene, ethylene-acrylic acid copolymer, and an antioxidant to form an aluminized receiving skin composition. This is then co-extruded with a heat-sealing layer composition and a substrate layer composition in three layers, followed by staged biaxial stretching, corona treatment, and vacuum evaporation to obtain an aluminized film. This invention enhances the interfacial bonding between the aluminum coating and the polyethylene base film, reduces the risk of aluminum layer detachment and metal transfer, and improves the film's airtightness, barrier stability, and applicability for subsequent processing.

Description

Technical Field

[0001] This invention belongs to the field of composite film preparation technology, and relates to a polyethylene aluminum-coated film composition, film, preparation method and application. Background Technology

[0002] Biaxially oriented polyethylene (BOE) metallized film combines the flexibility, lightweight, and processing adaptability of polyethylene film with the barrier, light-blocking, and decorative properties of a metallic coating. It has been widely used in food, daily chemical, and pharmaceutical packaging, as well as related composite packaging materials. With increasingly stringent requirements for barrier properties, airtightness, subsequent lamination adaptability, and stability in packaging materials, BOE metallized film not only needs to possess good initial barrier effects but also needs to maintain the integrity and interfacial stability of the metallized layer during winding, slitting, lamination, heat treatment, and end-use.

[0003] Existing biaxially oriented polyethylene (BPE) metallized films are typically prepared using vacuum evaporation of aluminum. However, polyethylene itself is a non-polar system, and its surface has limited interfacial anchoring ability to the metal layer, resulting in unstable interfacial bonding between the aluminum coating and the polyethylene base film. Consequently, during winding, lamination, heat treatment, or use, the aluminum coating is prone to problems such as localized peeling, cracking, metal transfer, or loss of continuity, thus affecting the film's airtightness, barrier stability, and subsequent processing performance.

[0004] Furthermore, existing technologies for improving aluminum plating adhesion often rely on conventional polar resins, surface additives, or simple surface treatments, which can lead to problems such as limited interfacial interaction, insufficient compatibility with the polyethylene matrix, limited processing window, or unstable adhesion improvement. Especially when considering biaxial stretching, aluminum plating layer bonding stability, film barrier properties, and packaging application adaptability, existing solutions still struggle to construct an aluminum plating receiving layer system on the polyethylene film surface that combines good compatibility, interfacial anchoring ability, and vapor deposition compatibility. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a polyethylene aluminized film composition, film, preparation method, and application. By constructing an aluminized receiving skin containing vinyl phosphate anchoring resin and ethylene-acrylic acid copolymer, and combining staged stretching, corona treatment, and vacuum evaporation, the interfacial bonding stability between the aluminum coating and the polyethylene base film is improved, the risk of aluminum layer detachment and metal transfer is reduced, and the film's airtightness, barrier stability, and processing applicability are enhanced, thereby meeting the needs of actual production.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for preparing a polyethylene aluminized film composition, the method comprising:

[0008] S1, lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, acetoacetic acid methyl methacrylate, xylene / n-butanol mixed solvent and azobisisobutyronitrile are mixed and reacted to obtain a hydroxyl-containing acrylate copolymer.

[0009] S2, ethylene-methyl acrylate-glycidyl methacrylate random terpolymer is mixed with hydroxyl-containing acrylate copolymer and extruded in a twin-screw extruder to obtain vinyl phosphate anchoring resin;

[0010] S3, metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant and phosphite antioxidant are mixed and extruded to obtain an aluminized receiving skin composition; hexene copolymer linear low-density polyethylene, low-density polyethylene and fumed silica are mixed to obtain a heat-sealing layer composition; high-density polyethylene and linear low-density polyethylene are mixed to obtain a base layer composition. The obtained aluminized receiving skin composition, heat-sealing layer composition and base layer composition are the polyethylene aluminized film composition.

[0011] The preparation method of the polyethylene aluminized film composition specifically includes:

[0012] S1, lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, ethyl acetoacetate methacrylate and xylene / n-butanol mixed solvent are mixed, heated to 75-85℃ under nitrogen atmosphere, azobisisobutyronitrile is added and reacted for 4-6h, then heated to 85-95℃ and held for 1-2h, distilled under reduced pressure and dried to obtain hydroxyl-containing acrylate copolymer;

[0013] S2, ethylene-methyl acrylate-glycidyl methacrylate random terpolymer and hydroxyl-containing acrylate copolymer are mixed and added to a twin-screw extruder, extruded, cooled and pelletized to obtain vinyl phosphate anchoring resin;

[0014] S3, metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant and phosphite antioxidant are added to a mixer and extruded and granulated to obtain an aluminized receiving skin composition. Hexene copolymer linear low-density polyethylene, low-density polyethylene and fumed silica are mixed to obtain a heat-sealing layer composition. High-density polyethylene and linear low-density polyethylene are mixed to obtain a base layer composition. The obtained aluminized receiving skin composition, heat-sealing layer composition and base layer composition are the polyethylene aluminized film composition.

[0015] Lauryl methacrylate, after polymerization, provides long-chain alkyl side groups in the copolymer. These side groups interact primarily with the polyethylene segments through chain entanglement and intermolecular interactions, reducing the tendency for phase separation between the polar copolymer and the continuous polyethylene phase. This allows the copolymer containing polar groups to be stably dispersed in the aluminized receiving skin. Isobornyl methacrylate introduces large-volume cyclic side groups into the copolymer, restricting local chain rotation and reducing interfacial flow during subsequent stretching and vapor deposition. 2-Methyl-2-acrylate-2-hydroxyethyl phosphate fixes the phosphate group on the polymer side chain, and the oxygen atom in the phosphate group can participate in the interaction with the metal surface as an interfacial electron donor site. Hydroxyethyl methacrylate provides hydroxyl groups for subsequent reactions with epoxy groups. Ethyl acetoacetate introduces a carbonyl structure into the copolymer; the carbonyl oxygen increases local polarity and provides additional polar interaction sites at the metallization interface.

[0016] The glycidyl acrylate group in the ethylene-methyl acrylate-glycidyl methacrylate random terpolymer contains an epoxy group. At extrusion temperature, the epoxy group undergoes a ring-opening reaction with the hydroxyl groups in the hydroxyl-containing acrylate copolymer to generate a hydroxyl ether structure. This reaction grafts the acrylate copolymer containing phosphate ester groups, carbonyl groups, and long-chain side groups onto the ethylene backbone, fixing the polar groups onto the ethylene-type resin backbone. The grafted vinyl phosphate anchored resin simultaneously possesses ethylene segments and polar side groups. The ethylene segments ensure that the resin can enter the continuous phase formed by metallocene linear low-density polyethylene, while the polar side groups remain inside the skin layer and near the surface, not migrating as free small molecules. The aluminized receiving skin layer maintains both the continuity of the polyethylene system and retains polar sites that can interact with the metal interface.

[0017] The carboxyl groups in the ethylene-acrylic acid copolymer increase the polarity density of the aluminized receiver skin. When carboxyl groups are distributed on the ethylene segments, they do not disrupt the continuity of the ethylene phase and can provide acidic oxygen-containing sites near the interface. When vinyl phosphate anchoring resin coexists with the ethylene-acrylic acid copolymer, the aluminized receiver skin simultaneously contains phosphate, hydroxyl, carbonyl, and carboxyl groups. Phosphate and carboxyl groups improve the surface response to corona treatment. Carboxyl groups can also reduce the degree of embedding of polar groups by non-polar polyethylene segments, making it easier for polar sites to be distributed on the surface of the aluminized receiver skin. The resulting skin is not a simple polyethylene surface, but a polar surface layer with ethylene segments as the continuous phase and phosphate, hydroxyl, carbonyl, and carboxyl groups as surface active sites.

[0018] The phased stretching alters the distribution of components in the aluminized receiver skin along its thickness and surface. The first phase, longitudinal stretching, orients the metallocene linear low-density polyethylene and its compatible vinyl resin along the stretching direction, while the vinyl phosphate anchoring resin grafted onto the ethylene backbone undergoes orientation and rearrangement along with the continuous phase. The holding phase provides time for chain segment relaxation and redistribution, reducing localized stress concentration of polar components. The second phase, involving both longitudinal and transverse stretching, further thins the aluminized receiver skin, bringing the polar segments originally distributed within the skin closer to the free surface and increasing the area fraction of polar groups in the surface layer.

[0019] During corona treatment, the polyethylene surface segments oxidize, forming oxygen-containing structures such as hydroxyl, carbonyl, and carboxyl groups. The existing phosphate ester, carboxyl, hydroxyl, and carbonyl groups in the aluminized receiver skin layer overlap with the newly generated oxygen-containing structures, further increasing the density of oxygen-containing sites on the surface. Corona treatment also reduces the inert coverage of the surface ethylene segments, exposing more polar groups previously located in the adjacent regions to the interface. After corona treatment, the surface of the aluminized receiver skin layer is no longer dominated by pure hydrocarbon chains, but transforms into a complex polar interface containing phosphate ester, carboxyl, hydroxyl, carbonyl groups, and oxidized polyethylene segments.

[0020] During vacuum evaporation, the aluminum atoms reaching the surface first contact this composite polar interface. Aluminum has an affinity for oxygen, and the initial interface between the aluminum plating layer and the base film primarily involves interactions between aluminum, alumina, and oxygen-containing functional groups. The phosphate groups from 2-methyl-2-acrylate-2-hydroxyethyl phosphate can coordinate with the metal centers on the aluminum surface via phosphoryl oxygen, forming a metal-oxygen-phosphorus anchoring bond on the alumina surface. The carboxyl groups in the ethylene-acrylic acid copolymer, the residual hydroxyl groups in hydroxyethyl methacrylate, and the carbonyl groups in ethyl acetoacetate methacrylate form acid-base interactions, hydrogen bonds, and dipole interactions with the aluminum and alumina surfaces. The evaporation interface simultaneously exhibits phosphate anchoring, carboxyl adsorption, hydroxyl interactions, and carbonyl polar interactions. Interfacial bonding no longer depends on a single surface energy increase but rather on the combined action of multiple oxygen-containing sites on the same interface.

[0021] After the aforementioned interfacial interaction occurs between the aluminum plating layer and the aluminum receiving skin, the failure mode of the aluminum layer changes during winding, lamination, heat treatment, and use. On pure polyethylene surfaces, the aluminum layer primarily exhibits interfacial desorption; once the local interface is disrupted, cracks and metal transfer easily propagate along the interface. In the aluminum receiving skin containing vinyl phosphate anchoring resin and ethylene-acrylic acid copolymer, interfacial disruption requires overcoming the metal-oxygen-phosphorus anchoring effect, the polar adsorption of carboxyl and hydroxyl groups, and the supporting effect of continuous ethylene on the interfacial layer. This elongates the interfacial desorption path, reducing overall aluminum layer peeling and localized metal transfer. Maintaining the continuity of the aluminum coating reduces gas permeation channels along cracks, pinholes, and delamination areas, thereby improving the film's airtightness and barrier stability.

[0022] As a preferred embodiment of the present invention, in S1, the mass ratio of lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, acetoacetic acid methyl methacrylate, xylene / n-butanol mixed solvent to azobisisobutyronitrile is (42-58):(15-25):(5-12):(4-10):(2-8):(80-120):(0.8-1.5), for example, it can be (42, 43.6, 45.2, 46.8, 48.4, 50, 51.6, 53.2, 54.8, 56.4 or 58):(15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25): (5, 5.7, 6.4, 7.1, 7.8, 8.5, 9.2, 9.9, 10.6, 11.3 or 12): (4, 4.6, 5.2, 5.8, 6.4, 7, 7.6, 8.2, 8.8, 9.4 or 10): (2, 2.6, 3.2, 3.8, 4.4, 5, 5.6, 6.2, 6.8, 7.4 or 8): (80, 84, 88, 92, 96, 100, 104, 108, 112, 116 or 120): (0.8, 0.87, 0.94, 1.01, 1.08, 1.15, 1.22, 1.29, 1.36, 1.43 or 1.5), but not limited to the listed values; other unlisted values ​​within this range also apply.

[0023] In some optional embodiments, the mass ratio of xylene to n-butanol in the xylene / n-butanol mixed solvent is 3:1.

[0024] As a preferred embodiment of the present invention, in S2, the mass ratio of the ethylene-methyl acrylate-glycidyl methacrylate random terpolymer to the hydroxyl-containing acrylate copolymer is 100:(15-35), for example, it can be 100:(15, 17, 19, 21, 23, 25, 27, 29, 31, 33 or 35), but it is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0025] In some optional embodiments, the melt flow rate of the ethylene-methyl acrylate-glycidyl methacrylate random terpolymer is 9.8-10.2 g / 10 min, and the density is 0.94-0.96 g / cm³. 3 .

[0026] In some optional embodiments, the parameters of the twin-screw extruder are as follows: zone 1 temperature 170-180℃, zone 2 temperature 180-190℃, zone 3 temperature 190-195℃, zone 4 temperature 195-200℃, die temperature 200-205℃, screw speed 150-300 rpm, and melt residence time 1-3 min. For example, the temperature could be: Zone 1: (170, 171, 172, 173, 174, 175, 176, 177, 178, 179, or 180)℃; Zone 2: (180, 181, 182, 183, 184, 185, 186, 187, 188, 189, or 190)℃; Zone 3: (190, 190.5, 191, 191.5, 192, 192.5, 193, 193.5, 194, 194.5, or 195)℃; Zone 4: (195, 195.5, 196, 196.5, 197, 197.5, 198, 198.5, 1...) The following values ​​are applicable: 99, 199.5, or 200 °C; die head temperature: (200, 200.5, 201, 201.5, 202, 202.5, 203, 203.5, 204, 204.5, or 205) °C; screw speed: (150, 165, 180, 195, 210, 225, 240, 255, 270, 285, or 300) rpm; melt residence time: (1.0, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, or 3.0) min. However, these values ​​are not limited to those listed; other unlisted values ​​within this range also apply.

[0027] As a preferred embodiment of the present invention, in S3, the mass ratio of the metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant is (75-90):(10-25):(5-12):(0.05-0.2):(0.03-0.15), for example, it can be (75, 76.5, 78, 79.5, 81, 82.5, 84, 85.5, 87, 88.5 or 90):(10, 11.5, 13, 14.5, 16, 17.5, 19, 20.5, 22, 23). 0.5 or 25): (5, 5.7, 6.4, 7.1, 7.8, 8.5, 9.2, 9.9, 10.6, 11.3 or 12): (0.05, 0.065, 0.08, 0.095, 0.11, 0.125, 0.14, 0.155, 0.17, 0.185 or 0.2): (0.03, 0.042, 0.054, 0.066, 0.078, 0.09, 0.102, 0.114, 0.126, 0.138 or 0.15), but not limited to the listed values; other unlisted values ​​within this range also apply.

[0028] In some optional embodiments, the metallocene linear low-density polyethylene has a melt mass flow rate of 0.65-2 g / 10 min and a density of 0.880-0.882 g / cm³. 3 .

[0029] In some optional embodiments, the hindered phenolic antioxidant is one or more of antioxidant 1010, antioxidant 1076, and antioxidant 1330.

[0030] In some optional embodiments, the phosphite antioxidant is one or more of antioxidant 168, antioxidant 6260, and antioxidant 626.

[0031] In some optional embodiments, the mass ratio of the hexene copolymer linear low-density polyethylene, low-density polyethylene, and fumed silica is (85-95):(5-15):(1-2), for example, it can be (85, 86, 87, 88, 89, 90, 91, 92, 93, 94 or 95):(5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15):(1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or 2.0), but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0032] In some optional embodiments, the melt mass flow rate of the hexene copolymer linear low-density polyethylene is 1-3.5 g / min, and the density is 0.918-0.923 g / cm³. 3 .

[0033] In some optional embodiments, the low-density polyethylene has a melt mass flow rate of 0.25-0.35 g / min and a density of 0.919-0.922 g / cm³. 3 .

[0034] In some optional embodiments, the native particle size of the fumed silica is 20-30 nm, for example, it can be 20 nm, 21 nm, 22 nm, 23 nm, 24 nm, 25 nm, 26 nm, 27 nm, 28 nm, 29 nm or 30 nm, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0035] In some alternative embodiments, the mass ratio of high-density polyethylene to linear low-density polyethylene is (55-70):(30-45), for example, it can be (55, 56.5, 58, 59.5, 61, 62.5, 64, 65.5, 67, 68.5 or 70):(30, 31.5, 33, 34.5, 36, 37.5, 39, 40.5, 42, 43.5 or 45), but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0036] In some optional embodiments, the high-density polyethylene has a melt mass flow rate of 4.0-8.0 g / 10 min and a density of 0.942-0.948 g / cm³. 3 .

[0037] In some optional embodiments, the linear low-density polyethylene has a melt mass flow rate of 1.7-2.3 g / 10 min and a density of 0.918-0.929 g / cm³. 3 .

[0038] Secondly, the present invention provides a method for preparing aluminized polyethylene film, the method comprising:

[0039] The heat-sealing layer composition, the substrate layer composition, and the aluminized receiving skin layer composition prepared by the preparation method described in the first aspect are respectively added to an extruder and co-extruded in three layers to obtain an unstretched original film; the unstretched original film is stretched in stages to obtain a biaxially oriented polyethylene film; then, the aluminized receiving skin layer side of the biaxially oriented polyethylene film is subjected to corona treatment; the corona-treated biaxially oriented polyethylene film is subjected to vacuum evaporation to obtain a polyethylene aluminized film.

[0040] In some optional embodiments, the thickness ratio of the heat-sealing layer, the substrate layer, and the aluminized receiving skin layer in the unstretched original film is (15-25):(55-75):(10-20), for example, it can be (15, 16, 17, 18, 19, 20, 21, 22, 23, 24 or 25):(55, 57, 59, 61, 63, 65, 67, 69, 71, 73 or 75):(10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20), but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0041] As a preferred embodiment of the present invention, the segmented stretching is performed as follows: a first longitudinal stretch is performed at 90-105℃, with a stretching ratio of 2.0-3.5; followed by holding at 95-115℃ for 2-15 seconds; then a second longitudinal stretch is performed at 95-115℃, with a stretching ratio of 1.3-2.5, controlling the total longitudinal stretching ratio to be 4-6; and finally, a transverse stretch is performed at 105-125℃, with a stretching ratio of 5-8. For example, it could be: performing a first longitudinal stretch at (90, 91.5, 93, 94.5, 96, 97.5, 99, 100.5, 102, 103.5 or 105) °C, with a first longitudinal stretch ratio of (2.0, 2.15, 2.3, 2.45, 2.6, 2.75, 2.9, 3.05, 3.2, 3.35 or 3.5); followed by (9 Hold at 5, 97, 99, 101, 103, 105, 107, 109, 111, 113, or 115°C for (2, 3.3, 4.6, 5.9, 7.2, 8.5, 9.8, 11.1, 12.4, 13.7, or 15) seconds; then heat at (95, 97, 99, 101, 103, 105, 107, 109, 111, 113, or 115°C for (2, 3.3, 4.6, 5.9, 7.2, 8.5, 9.8, 11.1, 12.4, 13.7, or 15) seconds. 15) Perform a second longitudinal stretch at ℃, with a longitudinal stretch ratio of (1.3, 1.42, 1.54, 1.66, 1.78, 1.9, 2.02, 2.14, 2.26, 2.38 or 2.5), and control the total longitudinal stretch ratio to (4, 4.2, 4.4, 4.6, 4.8, 5, 5.2, 5.4, 5.6, 5.8 or 6); then perform a transverse stretch at (105, 107, 109, 111, 113, 115, 117, 119, 121, 123 or 125) ℃, with a transverse stretch ratio of (5, 5.3, 5.6, 5.9, 6.2, 6.5, 6.8, 7.1, 7.4, 7.7 or 8), but not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0042] In some optional embodiments, the power density of the corona treatment is 10-20 W·min / m³.2 For example, it could be 10 W·min / m 2 11 W·min / m 2 12W·min / m 2 13W·min / m 2 14 W·min / m 2 15W·min / m 2 16 W·min / m 2 17W·min / m 2 18W·min / m 2 19 W·min / m 2 Or 20 W·min / m 2 However, this does not apply to all values ​​listed; other unlisted values ​​within the same range also apply.

[0043] In some optional embodiments, the vacuum evaporation is performed using an aluminum wire as the evaporation source, under conditions where the absolute pressure of the chamber is not higher than 5.0 × 10⁻⁴ mbar and the substrate temperature is lower than 60°C, for a evaporation time of 0.5-5.0 s, so that aluminum is deposited on the surface of the aluminum-plated receiving skin to form an aluminum coating with a thickness of 30-60 nm. For example, it can be performed under conditions where the absolute pressure of the chamber is not higher than 5.0 × 10⁻⁴ mbar and the substrate temperature is lower than 60°C, for a evaporation time of (0.5, 0.95, 1.4, 1.85, 2.3, 2.75, 3.2, 3.65, 4.1, 4.55, or 5.0) s, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0044] Thirdly, the present invention provides a polyethylene aluminized film composition prepared by the preparation method described in the first aspect.

[0045] Fourthly, the present invention provides a polyethylene aluminized film prepared by the preparation method described in the second aspect.

[0046] Fifthly, the polyethylene aluminized film provided by this invention can be used in food, daily chemical products, or pharmaceutical packaging materials.

[0047] Compared with existing technologies, the beneficial effects of this invention are as follows: By introducing vinyl phosphate anchoring resin and ethylene-acrylic acid copolymer into the aluminized receiving skin layer, this invention forms an interface layer containing phosphate groups, hydroxyl groups, carboxyl groups, and carbonyl groups on the surface of the polyethylene film. Combined with staged stretching, corona treatment, and vacuum evaporation, this enhances the interfacial bonding between the aluminum coating and the base film, reducing aluminum layer peeling, cracking, and metal transfer. While maintaining the processing adaptability of biaxially oriented polyethylene film, it improves the continuity and stability of the aluminized layer, which is beneficial for improving the film's airtightness, barrier stability, subsequent composite applicability, and packaging reliability. Furthermore, the biaxially oriented polyethylene aluminized film provided by this invention can also be used as a surface-reinforcing barrier layer for thermoplastic polyolefin (TPO) waterproof membranes. Utilizing the excellent thermal compatibility of both the polyethylene film and TPO membrane as polyolefin systems, the aluminized layer provides additional airtightness and moisture barrier while avoiding the risk of interlayer delamination between dissimilar materials, thus expanding the application of this invention's film in the field of building waterproofing. Attached Figure Description

[0048] Figure 1 The FTIR image of the hydroxyl-containing acrylate copolymer provided in Example 1 of the present invention;

[0049] Figure 2 The image shows the FTIR spectrum of the vinyl phosphate anchoring resin provided in Example 1 of this invention. Detailed Implementation

[0050] The technical solutions of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings. The embodiments described herein are specific implementations of the present invention, used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary, and should not be construed as limiting the implementation methods or the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0051] The chemical reagents used in the embodiments and comparative examples of this invention are all commercially available products and have not undergone any further purification treatment.

[0052] It should be noted that the evaporation time and aluminum coating thickness described in each embodiment are the process conditions of the corresponding embodiment, which are used to limit the formation process and final thickness of the aluminum coating in each embodiment; this application does not use evaporation time as the only variable to establish a one-to-one linear correspondence between evaporation time and aluminum coating thickness.

[0053] Example 1

[0054] This embodiment provides a polyethylene aluminized film composition, a film, and a preparation method thereof. The preparation method specifically includes the following steps:

[0055] S1, lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, ethyl acetoacetate methacrylate, and xylene / n-butanol mixed solvent are mixed, wherein the mass ratio of xylene to n-butanol in the xylene / n-butanol mixed solvent is 3:1. The mixture is heated to 75°C under a nitrogen atmosphere, and azobisisobutyronitrile is added and reacted for 6 hours. Then the temperature is raised to 85°C and held for 2 hours. The mixture is then distilled under reduced pressure and dried to obtain a hydroxyl-containing acrylate copolymer. The mass ratio of lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, ethyl acetoacetate methacrylate, xylene / n-butanol mixed solvent, and azobisisobutyronitrile is 42:25:12:4:8:80:1.5.

[0056] S2, ethylene-methyl acrylate-glycidyl methacrylate random terpolymer and hydroxyl-containing acrylate copolymer are mixed and added to a twin-screw extruder. The mass ratio of the ethylene-methyl acrylate-glycidyl methacrylate random terpolymer to the hydroxyl-containing acrylate copolymer is 100:15. The parameters of the twin-screw extruder are: zone 1 temperature 170℃, zone 2 temperature 190℃, zone 3 temperature 190℃, zone 4 temperature 200℃, die temperature 200℃, screw speed 300 rpm, melt residence time 1 min. The mixture is extruded, cooled, and pelletized to obtain vinyl phosphate anchoring resin.

[0057] S3, metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant are added to a mixer, and extruded and granulated to obtain an aluminized receiving skin composition. The mass ratio of the metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant is 90:10:5:0.2:0.03. The hindered phenolic antioxidant is antioxidant 1010, and the phosphite antioxidant is antioxidant 168. Hexene copolymer linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant are added to a mixer, and extruded and granulated to obtain an aluminized receiving skin composition. A heat-sealing layer composition is obtained by mixing low-density polyethylene (LDPE), LDPE, and fumed silica, wherein the mass ratio of the LDPE, LDPE, and fumed silica is 95:5:1, and the native particle size of the fumed silica is 20 nm. A matrix layer composition is obtained by mixing high-density polyethylene (HDPE) and LDPE, wherein the mass ratio of HDPE to LDPE is 55:45. The resulting aluminized receiving skin composition, the heat-sealing layer composition, and the matrix layer composition constitute the polyethylene aluminized film composition.

[0058] S4, the heat-sealing layer composition, the substrate layer composition, and the aluminized receiving skin layer composition are respectively added to an extruder and co-extruded in three layers to obtain an unstretched raw film. The thickness ratio of the heat-sealing layer, the substrate layer, and the aluminized receiving skin layer in the unstretched raw film is 15:75:10. The unstretched raw film is then stretched in stages. The staged stretching is as follows: a first stage of longitudinal stretching is performed at 90°C with a first stage longitudinal stretching ratio of 3.5; then, it is held at 95°C for 15 seconds; a second stage of longitudinal stretching is performed at 95°C with a second stage longitudinal stretching ratio of 1.3, controlling the total longitudinal stretching ratio to be 4.55; then, a transverse stretching is performed at 125°C with a transverse stretching ratio of 8, to obtain a biaxially oriented polyethylene film. The aluminized receiving skin layer side of the biaxially oriented polyethylene film is then subjected to corona treatment with a power density of 10 W·min / m. 2 The biaxially oriented polyethylene film after corona treatment was subjected to vacuum evaporation. The vacuum evaporation process involved using aluminum wire as the evaporation source, with an absolute pressure in the cavity not exceeding 5.0 × 10⁻⁶. -4 Vacuum evaporation was performed under conditions of mbar and substrate temperature below 60℃ for 0.5s to obtain a polyethylene aluminum-coated film.

[0059] Figure 1 The FTIR image of the hydroxyl-containing acrylate copolymer provided in this embodiment is 3392 cm⁻¹. -1 The peak is broad and belongs to the O–H stretching vibration, corresponding to the hydroxyl group in hydroxyethyl methacrylate and the hydroxyl-containing environment in 2-methyl-2-acrylate-2-hydroxyethyl phosphate; 2956 cm⁻¹ -1 2925cm -1 2854cm -1 Belongs to the CH2 / CH3 stretching vibration; 1731 cm -1 Belongs to the C=O stretching vibration of the ester group; 1712 cm⁻¹ -1 This belongs to the stretching vibration of the carbonyl group in the acetoacetate ester structure, corresponding to the acetoacetyl methacrylate unit; 1462 cm⁻¹ -1 1382cm -1 Belongs to the CH2 / CH3 bending vibration, corresponding to the methyl and methylene structures in long-chain alkyl groups and side groups; 1083-1034 cm⁻¹ -1 It belongs to the P–O–C and C–O stretching vibrations, corresponding to phosphate ester groups and hydroxyethyl ester structures.

[0060] Figure 2 The FTIR image of the vinyl phosphate anchoring resin provided in this embodiment, 3460-3320 cm⁻¹ -1The peak is broad and belongs to the O–H stretching vibration, corresponding to the residual hydroxyl group of hydroxyethyl methacrylate and the hydroxyl group generated after epoxy ring opening; 1105-1032 cm⁻¹ -1 It belongs to the P–O–C, C–O and ether bond related absorption, corresponding to the phosphate ester group and the ether bond structure formed after the ring opening of hydroxyethyl methacrylate and glycidyl methacrylate.

[0061] Example 2

[0062] This embodiment provides a polyethylene aluminized film composition, a film, and a preparation method thereof. The preparation method specifically includes the following steps:

[0063] S1, lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, ethyl acetoacetate methacrylate, and xylene / n-butanol mixed solvent are mixed, wherein the mass ratio of xylene to n-butanol in the xylene / n-butanol mixed solvent is 3:1. The mixture is heated to 85°C under a nitrogen atmosphere, and azobisisobutyronitrile is added and reacted for 4 hours. Then the temperature is raised to 95°C and held for 1 hour. The mixture is then distilled under reduced pressure and dried to obtain a hydroxyl-containing acrylate copolymer. The mass ratio of lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, ethyl acetoacetate methacrylate, xylene / n-butanol mixed solvent, and azobisisobutyronitrile is 58:15:5:10:2:120:0.8.

[0064] S2, ethylene-methyl acrylate-glycidyl methacrylate random terpolymer and hydroxyl-containing acrylate copolymer are mixed and added to a twin-screw extruder. The mass ratio of the ethylene-methyl acrylate-glycidyl methacrylate random terpolymer to the hydroxyl-containing acrylate copolymer is 100:35. The parameters of the twin-screw extruder are: zone 1 temperature 180℃, zone 2 temperature 180℃, zone 3 temperature 195℃, zone 4 temperature 195℃, die temperature 205℃, screw speed 150rpm, melt residence time 3min. The mixture is extruded, cooled, and pelletized to obtain vinyl phosphate anchoring resin.

[0065] S3, metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant are added to a mixer, and extruded and granulated to obtain an aluminized receiving skin composition. The mass ratio of the metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant is 75:25:12:0.05:0.15. The hindered phenolic antioxidant is antioxidant 1076 and antioxidant 1330 in a mass ratio of 1:1. The phosphite antioxidant is antioxidant 626. 0. A heat-sealing layer composition is obtained by mixing hexene copolymer linear low-density polyethylene, low-density polyethylene, and fumed silica, wherein the mass ratio of the hexene copolymer linear low-density polyethylene, low-density polyethylene, and fumed silica is 85:15:2, and the original particle size of the fumed silica is 30 nm. A matrix layer composition is obtained by mixing high-density polyethylene and linear low-density polyethylene, wherein the mass ratio of high-density polyethylene to linear low-density polyethylene is 70:30. The resulting aluminized receiving skin composition, the heat-sealing layer composition, and the matrix layer composition are the polyethylene aluminized film composition.

[0066] S4, the heat-sealing layer composition, the substrate layer composition, and the aluminized receiving skin layer composition are respectively added to an extruder and co-extruded in three layers to obtain an unstretched raw film. The thickness ratio of the heat-sealing layer, the substrate layer, and the aluminized receiving skin layer in the unstretched raw film is 25:55:20. The unstretched raw film is then stretched in stages. The staged stretching is as follows: a first stage of longitudinal stretching is performed at 105°C with a first stage longitudinal stretching ratio of 2.0; followed by holding at 115°C for 2 seconds; then a second stage of longitudinal stretching is performed at 115°C with a second stage longitudinal stretching ratio of 2.5, controlling the total longitudinal stretching ratio to 5; then a transverse stretching is performed at 105°C with a transverse stretching ratio of 5, to obtain a biaxially oriented polyethylene film. The aluminized receiving skin layer side of the biaxially oriented polyethylene film is then subjected to corona treatment with a power density of 20 W·min / m. 2 The biaxially oriented polyethylene film after corona treatment was subjected to vacuum evaporation. The vacuum evaporation process involved using aluminum wire as the evaporation source, with an absolute pressure in the cavity not exceeding 5.0 × 10⁻⁶. -4 Vacuum evaporation was performed under conditions of mbar and substrate temperature below 60℃ for 5.0s to obtain a polyethylene aluminum-coated film.

[0067] Example 3

[0068] This embodiment provides a polyethylene aluminized film composition, a film, and a preparation method thereof. The preparation method specifically includes the following steps:

[0069] S1, lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, ethyl acetoacetate methacrylate, and xylene / n-butanol mixed solvent are mixed, wherein the mass ratio of xylene to n-butanol in the xylene / n-butanol mixed solvent is 3:1. The mixture is heated to 80°C under a nitrogen atmosphere, and azobisisobutyronitrile is added and reacted for 5 hours. Then the temperature is raised to 90°C and held for 1.5 hours. The mixture is then distilled under reduced pressure and dried to obtain a hydroxyl-containing acrylate copolymer. The mass ratio of lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, ethyl acetoacetate methacrylate, xylene / n-butanol mixed solvent, and azobisisobutyronitrile is 50:20:8:7:5:100:1.2.

[0070] S2, ethylene-methyl acrylate-glycidyl methacrylate random terpolymer and hydroxyl-containing acrylate copolymer are mixed and added to a twin-screw extruder. The mass ratio of the ethylene-methyl acrylate-glycidyl methacrylate random terpolymer to the hydroxyl-containing acrylate copolymer is 100:25. The parameters of the twin-screw extruder are: zone 1 temperature 175℃, zone 2 temperature 185℃, zone 3 temperature 192℃, zone 4 temperature 198℃, die temperature 202℃, screw speed 220rpm, melt residence time 2min. The mixture is extruded, cooled, and pelletized to obtain vinyl phosphate anchoring resin.

[0071] S3, metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant are added to a mixer, and extruded and granulated to obtain an aluminized receiving skin composition. The mass ratio of the metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant is 82:18:8:0.1:0.08. The hindered phenolic antioxidant is antioxidant 1330, and the phosphite antioxidants are antioxidant 168 and antioxidant 626, with a mass ratio of 1:1. A heat-sealing layer composition is obtained by mixing hexene copolymer linear low-density polyethylene, low-density polyethylene, and fumed silica, wherein the mass ratio of the hexene copolymer linear low-density polyethylene, low-density polyethylene, and fumed silica is 90:10:1.5, and the original particle size of the fumed silica is 25 nm. A matrix layer composition is obtained by mixing high-density polyethylene and linear low-density polyethylene, wherein the mass ratio of high-density polyethylene to linear low-density polyethylene is 62:38. The resulting aluminized receiving skin composition, the heat-sealing layer composition, and the matrix layer composition constitute the polyethylene aluminized film composition.

[0072] S4, the heat-sealing layer composition, the substrate layer composition, and the aluminized receiving skin layer composition are respectively added to an extruder and co-extruded in three layers to obtain an unstretched raw film. The thickness ratio of the heat-sealing layer, the substrate layer, and the aluminized receiving skin layer in the unstretched raw film is 20:65:15. The unstretched raw film is then stretched in stages. The staged stretching is as follows: the first stage of longitudinal stretching is performed at 98°C with a first stage longitudinal stretching ratio of 2.8; then it is held at 105°C for 8 seconds; then the second stage of longitudinal stretching is performed at 105°C with a second stage longitudinal stretching ratio of 1.9, controlling the total longitudinal stretching ratio to be 5.32; then the transverse stretching is performed at 115°C with a transverse stretching ratio of 6.5 to obtain a biaxially oriented polyethylene film. The aluminized receiving skin layer side of the biaxially oriented polyethylene film is then subjected to corona treatment with a power density of 13 W·min / m. 2 The biaxially oriented polyethylene film after corona treatment was subjected to vacuum evaporation. The vacuum evaporation process involved using aluminum wire as the evaporation source, with an absolute pressure in the cavity not exceeding 5.0 × 10⁻⁶. -4 Vacuum evaporation was performed under conditions of mbar and substrate temperature below 60℃ for 2.5s to obtain a polyethylene aluminum-coated film.

[0073] Example 4

[0074] This embodiment provides a polyethylene aluminized film composition, a film, and a preparation method thereof. The preparation method specifically includes the following steps:

[0075] S1, lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, ethyl acetoacetate methacrylate, and xylene / n-butanol mixed solvent are mixed, wherein the mass ratio of xylene to n-butanol in the xylene / n-butanol mixed solvent is 3:1. The mixture is heated to 82°C under a nitrogen atmosphere, and azobisisobutyronitrile is added and reacted for 5.5 h. Then the temperature is raised to 92°C and held for 1.2 h. The mixture is then distilled under reduced pressure and dried to obtain a hydroxyl-containing acrylate copolymer. The mass ratio of lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, ethyl acetoacetate methacrylate, xylene / n-butanol mixed solvent, and azobisisobutyronitrile is 46:18:10:6:6:90:1.0.

[0076] S2, ethylene-methyl acrylate-glycidyl methacrylate random terpolymer and hydroxyl-containing acrylate copolymer are mixed and added to a twin-screw extruder. The mass ratio of the ethylene-methyl acrylate-glycidyl methacrylate random terpolymer to the hydroxyl-containing acrylate copolymer is 100:28. The parameters of the twin-screw extruder are: zone 1 temperature 175℃, zone 2 temperature 185℃, zone 3 temperature 192℃, zone 4 temperature 198℃, die temperature 203℃, screw speed 250 rpm, melt residence time 1.5 min. The mixture is extruded, cooled, and pelletized to obtain vinyl phosphate anchoring resin.

[0077] S3, metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant are added to a mixer, and extruded and granulated to obtain an aluminized receiving skin composition. The mass ratio of the metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant is 85:15:10:0.15:0.10. The hindered phenolic antioxidant is antioxidant 1010, and the phosphite antioxidant is antioxidant 6260. Hexene copolymer linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant are added to a mixer, and extruded and granulated to obtain an aluminized receiving skin composition. A heat-sealing layer composition is obtained by mixing low-density polyethylene (LDPE), LDPE, and fumed silica, wherein the mass ratio of the LDPE, LDPE, and fumed silica is 92:8:1.2, and the native particle size of the fumed silica is 28 nm. A matrix layer composition is obtained by mixing high-density polyethylene (HDPE) and LDPE, wherein the mass ratio of HDPE to LDPE is 65:35. The resulting aluminized receiving skin composition, the heat-sealing layer composition, and the matrix layer composition constitute the polyethylene aluminized film composition.

[0078] S4, the heat-sealing layer composition, the substrate layer composition, and the aluminized receiving skin layer composition are respectively added to an extruder and co-extruded in three layers to obtain an unstretched raw film. The thickness ratio of the heat-sealing layer, the substrate layer, and the aluminized receiving skin layer in the unstretched raw film is 18:70:12. The unstretched raw film is then stretched in stages. The staged stretching is as follows: the first stage of longitudinal stretching is performed at 102°C with a first stage longitudinal stretching ratio of 3.2; then it is held at 110°C for 10 seconds; then the second stage of longitudinal stretching is performed at 110°C with a second stage longitudinal stretching ratio of 1.7, controlling the total longitudinal stretching ratio to be 5.44; then the transverse stretching is performed at 120°C with a transverse stretching ratio of 7, to obtain a biaxially oriented polyethylene film. The aluminized receiving skin layer side of the biaxially oriented polyethylene film is then subjected to corona treatment with a power density of 18 W·min / m². 2The biaxially oriented polyethylene film after corona treatment was subjected to vacuum evaporation. The vacuum evaporation process involved using aluminum wire as the evaporation source, with an absolute pressure in the cavity not exceeding 5.0 × 10⁻⁶. -4 Vacuum evaporation was performed under conditions of mbar and substrate temperature below 60℃ for 1.5s to obtain a polyethylene aluminum-coated film.

[0079] Comparative Example 1

[0080] This comparative example provides a polyethylene aluminized film composition, film, and preparation method. The difference between this example and Example 1 is that 2-methyl-2-acrylate-2-hydroxyethyl phosphate is not added in S1, but is replaced by an equal mass of hydroxyethyl methacrylate. Other process parameters and operating conditions are exactly the same as in Example 1.

[0081] Comparative Example 2

[0082] This comparative example provides a polyethylene aluminized film composition, film, and preparation method. The difference between this example and Example 1 is that, in S1, ethyl acetoacetate methacrylate is not added, and isobornyl methacrylate is substituted with an equal mass. Other process parameters and operating conditions are exactly the same as in Example 1.

[0083] Comparative Example 3

[0084] This comparative example provides a polyethylene aluminized film composition, film, and preparation method. The difference between this example and Example 1 is that the independent reactive extrusion process used in S2 to prepare the vinyl phosphate anchoring resin is not performed. Instead, the ethylene-methyl acrylate-glycidyl methacrylate random terpolymer and the hydroxyl-containing acrylate copolymer obtained in step S1 are premixed according to the corresponding ratio in Example 1 and used directly as a physical blending resin in S3 to prepare the aluminized receiving skin composition. The other raw material types, amounts, and process parameters of S3 and S4 are the same as in Example 1.

[0085] Comparative Example 4

[0086] This comparative example provides a polyethylene aluminized film composition, film, and preparation method. The difference between this example and Example 1 is that vinyl phosphate anchoring resin is not added in S3, and is replaced by an equal mass of metallocene linear low-density polyethylene. Other process parameters and operating conditions are exactly the same as in Example 1.

[0087] Performance testing:

[0088] The oxygen permeability test method was ASTM D 3985; the testing instrument was a MOCONOX-TRAN® 2 / 22(H); the test gas was oxygen (concentration ≥99.5%); the test temperature was 23.0℃; the test gas humidity was 0%RH, and the carrier gas humidity was 12.5%RH; the test area was 50.00 cm².2 The test mode is a cyclic convergence mode, with the convergence condition being that the deviation of three consecutive cycles does not exceed 1.0%, and the detection interval is 30 minutes.

[0089] The adhesion test method for the aluminized layer is as follows: A non-aluminized biaxially oriented polyester film with a thickness of (12±1.2) μm is used as the heat insulation base film. The aluminized side of the aluminized film / sheet to be tested is overlapped with the non-corona-electrode side of the ethylene-acrylic acid copolymer film, and then the heat insulation film is placed on top of the ethylene-acrylic acid copolymer film. This film sample assembly is placed flat in a heat sealer for heat sealing. The conditions are set as follows: upper sealing blade temperature (110±1)℃, lower sealing blade temperature (80±1)℃, and pressure (0.2±0.02) MPa. The heat sealing time is determined according to the thickness of the aluminized film / sheet: 0.5 seconds for a thickness less than 25 μm, and 1.0 second for a thickness greater than or equal to 25 μm. After heat sealing, the heat insulation film is removed, and the film is cooled in the test chamber for 10 minutes. From the cooled composite film, strip samples with a width of (15±0.1) mm and an unfolded length greater than 150 mm are cut along the direction perpendicular to the heat sealing line. The number of samples in each group is not less than 5. The samples were tested in a standard environment with a temperature of (23±2)℃ and a relative humidity of (50±10)%. Centered on the heat-sealed area, the sample was opened 180°, with the ethylene-acrylic acid copolymer film end and the aluminized film / sheet end clamped in the upper and lower clamps of the tensile testing machine, ensuring the sample was centered, aligned, and not loosened. The sample was adjusted to a standard T-shaped peel condition. The clamp spacing of the tensile testing machine was set to 50mm, and the test speed to 200mm / min. The testing machine was started to perform the T-shaped tensile peel test until the predetermined peel stroke was completed, and the peel load was recorded in real time. The result is expressed as N / 15mm.

[0090] The test results are shown in Table 1.

[0091] Table 1. Test results of polyethylene aluminized films in Examples 1-4 and Comparative Examples 1-4

[0092]

[0093] As shown in Table 1, compared with Example 1, the oxygen permeability of Comparative Example 1 increased and the peeling load decreased; the oxygen permeability of Comparative Example 2 increased and the peeling load decreased; the oxygen permeability of Comparative Example 3 increased and the peeling load decreased; and the oxygen permeability of Comparative Example 4 increased and the peeling load decreased.

[0094] This is because, in Comparative Example 1, after removing the phosphate ester monomer, the copolymer side chains lack phosphorus-containing sites that can form coordination anchors with the aluminum and alumina surfaces. The aluminum-plated receiving skin mainly relies on polar interactions such as hydroxyl, carbonyl, and carboxyl groups to maintain interfacial bonding, resulting in a decrease in interfacial anchoring density. The aluminum layer is more prone to local desorption and discontinuity disruption, thus reducing peel load and increasing oxygen permeability. In Comparative Example 2, after removing the acetoacetate monomer, the number of carbonyl auxiliary interaction sites in the aluminum-plated receiving skin is reduced, decreasing the number of oxygen-containing structures at the interface that can participate in polar adsorption and dipole interactions, thus reducing adhesion and barrier properties. In Comparative Example 3, after switching to ordinary melt blending, the hydroxyl-containing acrylate copolymer is not fixed on the ethylene backbone. The polar segments are more prone to migration and uneven local dispersion during melting, stretching, and subsequent winding, making it difficult to form a stable and continuous polar interfacial layer on the aluminum-plated surface. This leads to the aluminum layer bonding relying on local adsorption, decreased interfacial stability, and deterioration of peel load and airtightness. After completely removing the vinyl phosphate anchoring resin in Comparative Example 4, the aluminum-plated receiving skin lost the anchoring interface composed of phosphate groups, hydroxyl groups, and acetoacetate structures. The surface layer was mainly composed of a continuous polyethylene phase and an ethylene-acrylic acid copolymer. Lacking fixed high-density anchoring points, the aluminum layer was prone to desorption and metal transfer, thus reducing adhesion and increasing oxygen permeability.

[0095] The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for preparing a polyethylene aluminized film composition, characterized in that, The preparation method includes: S1, lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, acetoacetic acid methyl methacrylate, xylene / n-butanol mixed solvent and azobisisobutyronitrile are mixed and reacted to obtain a hydroxyl-containing acrylate copolymer. S2, ethylene-methyl acrylate-glycidyl methacrylate random terpolymer is mixed with hydroxyl-containing acrylate copolymer and extruded in a twin-screw extruder to obtain vinyl phosphate anchoring resin; S3, metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant and phosphite antioxidant are mixed and extruded to obtain an aluminized receiving skin composition; hexene copolymer linear low-density polyethylene, low-density polyethylene and fumed silica are mixed to obtain a heat-sealing layer composition; high-density polyethylene and linear low-density polyethylene are mixed to obtain a base layer composition. The obtained aluminized receiving skin composition, heat-sealing layer composition and base layer composition are the polyethylene aluminized film composition.

2. The method for preparing a polyethylene aluminized film composition according to claim 1, characterized in that, In S1: The mass ratio of lauryl methacrylate, isobornyl methacrylate, 2-methyl-2-acrylate-2-hydroxyethyl phosphate, hydroxyethyl methacrylate, ethyl acetoacetate, xylene / n-butanol mixed solvent to azobisisobutyronitrile is (42-58):(15-25):(5-12):(4-10):(2-8):(80-120):(0.8-1.5). The mass ratio of xylene to n-butanol in the xylene / n-butanol mixed solvent is 3:

1.

3. The method for preparing the polyethylene aluminized film composition according to claim 1, characterized in that, In S2: The mass ratio of the ethylene-methyl acrylate-glycidyl methacrylate random terpolymer to the hydroxyl-containing acrylate copolymer is 100:(15-35). The parameters of the twin-screw extruder are as follows: zone 1 temperature 170-180℃, zone 2 temperature 180-190℃, zone 3 temperature 190-195℃, zone 4 temperature 195-200℃, die temperature 200-205℃, screw speed 150-300rpm, and melt residence time 1-3min.

4. The method for preparing a polyethylene aluminized film composition according to claim 1, characterized in that, In S3: The mass ratio of the metallocene linear low-density polyethylene, vinyl phosphate anchoring resin, ethylene-acrylic acid copolymer, hindered phenolic antioxidant, and phosphite antioxidant is (75-90):(10-25):(5-12):(0.05-0.2):(0.03-0.15). The hindered phenolic antioxidant is one or more of antioxidant 1010, antioxidant 1076 and antioxidant 1330; The phosphite antioxidant is one or more of antioxidant 168, antioxidant 6260, and antioxidant 626; The mass ratio of the hexene copolymer linear low-density polyethylene, low-density polyethylene and fumed silica is (85-95):(5-15):(1-2).

5. The method for preparing a polyethylene aluminized film composition according to claim 1, characterized in that, In S3: the original particle size of the fumed silica is 20-30 nm; The mass ratio of high-density polyethylene to linear low-density polyethylene is (55-70):(30-45).

6. A method for preparing a polyethylene aluminum-coated film, characterized in that, The preparation is carried out using the polyethylene aluminized film composition according to any one of claims 1-5, specifically as follows: The heat-sealing layer composition, the substrate layer composition, and the aluminized receiving skin layer composition are respectively added to an extruder and co-extruded in three layers to obtain an unstretched original film. The unstretched original film is stretched in stages to obtain a biaxially oriented polyethylene film. Then, the aluminum receiving skin side of the biaxially oriented polyethylene film is subjected to corona treatment. The corona-treated biaxially oriented polyethylene film is then subjected to vacuum evaporation to obtain an aluminum-coated polyethylene film.

7. The method for preparing a polyethylene aluminized film according to claim 6, characterized in that, The thickness ratio of the heat-sealing layer, the substrate layer, and the aluminized receiving skin layer formed in the unstretched original film is (15-25):(55-75):(10-20). The staged stretching process is as follows: the first stage of longitudinal stretching is carried out at 90-105℃, with a stretching ratio of 2.0-3.5; followed by heat preservation at 95-115℃ for 2-15 seconds. Then, perform a second longitudinal stretch at 95-115℃, with a longitudinal stretch ratio of 1.3-2.5, and control the total longitudinal stretch ratio to be 4-6; then, perform a transverse stretch at 105-125℃, with a transverse stretch ratio of 5-8. The power density of the corona treatment is 10-20 W·min / m³. 2 ; The vacuum evaporation process involves using aluminum wire as the evaporation source, with the absolute pressure within the cavity not exceeding 5.0 × 10⁻⁶. -4 Vacuum evaporation was performed under conditions of mbar and substrate temperature below 60℃, with a evaporation time of 0.5-5.0s.

8. A polyethylene aluminized film composition, characterized in that, Obtained by the preparation method according to any one of claims 1-5.

9. Aluminum-coated polyethylene film, characterized in that, The preparation method according to claim 6 is used.

10. The application of the polyethylene aluminized film according to claim 9 in food, daily chemical products or pharmaceutical packaging materials.

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