Composite material package made of single polyolefin material and preparation method of composite material package

Abstract

The invention provides a composite material package made of a single polyolefin material and a preparation method of the composite material package. The package comprises an outer polyolefin printing layer, an outer bonding layer, a blocking layer, an inner bonding layer and a polyolefin heat sealing layer which are sequentially arranged from outside to inside. According to the composite material package made of the single polyolefin material and the preparation method of the composite material package, simplification of the package material is achieved, meanwhile, package pull pipe forming is good, hose package deformation recovery is fast, and recycling is facilitated.

Description

Technical Field

[0001] The invention relates to daily chemical oral care and other care packaging, in particular to a composite material packaging made of a single polyolefin material. Background Art

[0002] Conventional composite sheet packaging is mostly plastic aluminum-plastic composite film structure. Non-recyclable structures include PE / AL / PE, PE / MPET / PE, PE / EVOH / PE, etc., and recyclable structures include plastic extruded hoses, etc. Non-recyclable packaging films do not meet the increasingly severe environmental protection trend. Recyclable packaging films usually have poor dimensional stability, friction coefficient, and appearance after packaging, which makes it difficult to fully meet customer expectations. Although aluminum-plastic composite films can be recycled at this stage, there are actually few recycling companies and serious pollution. In addition, recycling technology is not yet mature, so recycling is still relatively difficult. Some traditional aluminum-plastic sheet structures are INK / PE / AL / PE, INK / PE / MPET / PE, etc., and the surface has poor tube forming properties, slow hose deformation recovery ability, and is difficult to separate and recycle. In addition, conventional landfill recycling of aluminum-plastic sheets leads to heavy metal pollution, and cremation recycling leads to incinerator compaction and other problems.

[0003] It is difficult for existing plastic composite film packaging to simultaneously achieve environmental protection and biodegradability, stable size and friction coefficient, exquisite appearance after packaging, high barrier and other requirements. Existing PE single material film bags mostly adopt PE / PE material structure, and both layers of PE are ordinary polyethylene resins. The moisture barrier, oxygen barrier and fragrance retention properties cannot meet the requirements of high-quality products. If a multi-layer co-extruded high-barrier PE material structure is adopted, since high-barrier materials are mostly EVOH, PA, PVDC and other materials, a certain thickness (≥3μm) must be reached to have sufficient barrier properties, and the above materials are not compatible with PE materials. Connecting resin (≥4μm) needs to be added during processing, which will inevitably cause a high content of non-polyethylene components in the multi-layer co-extruded film. The above materials have very low compatibility with polyethylene, which reduces the recycling rate and increases the difficulty of secondary processing. In addition, the cost of the multi-layer co-extrusion equipment required is extremely high, which makes the film making cost of the packaging high, and the production and processing are difficult. At the same time, the scrap rate is increased, resulting in great waste, and it is impossible to meet the requirements of circular packaging. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a composite material packaging made of a single polyolefin material and a preparation method thereof, which realizes the standardization of packaging materials, while achieving good packaging tube forming, fast deformation recovery of hose packaging, and is conducive to separation and recycling.

[0005] In order to achieve the purpose of the present invention, the present invention provides a composite material package of a single polyolefin material, the package comprising an outer polyolefin printing layer, an outer adhesive layer, a barrier layer, an inner adhesive layer and a polyolefin heat-sealing layer arranged in sequence from the outside to the inside; the outer adhesive layer comprises one of ethylene acrylic acid modified polyethylene, one-component polyurethane, two-component polyurethane, and polyether glue, or the outer adhesive layer comprises at least one of LDPE and HDPE; the inner adhesive layer comprises one of ethylene acrylic acid modified polyethylene, one-component polyurethane, two-component polyurethane, and polyether glue, or the inner adhesive layer comprises at least one of LDPE and HDPE. Wherein, the outer adhesive layer is used to composite the outer polyolefin printing layer and the barrier layer, and the inner adhesive layer is used to composite the barrier layer and the polyolefin heat-sealing layer.

[0006] Preferably, the outer polyolefin printing layer is a mixture of any two or more of low-density polyethylene, medium-density polyethylene, high-density polyethylene, metallocene polyethylene, homopolymer polypropylene, copolymer polypropylene, and random polypropylene. Preferably, the thickness of the outer polyolefin printing layer is 50-150 μm.

[0007] Preferably, the outer polyolefin printing layer is composed of low-density polyethylene, medium-density polyethylene, high-density polyethylene, and metallocene polyethylene, and the mass percentages thereof are: 20%~40%, 10%~30%, 30%~50%, and 10%~20%.

[0008] Preferably, the barrier layer is one or more of a metal-plated film, an inorganic oxide-plated film, an organic-plated film, a uniaxially or biaxially stretched single-layer film, a uniaxially stretched multilayer co-extruded film, a biaxially stretched multilayer co-extruded film, a multilayer co-extruded NY / PA film, an organic barrier film, and an inorganic barrier film.

[0009] Further preferably, the barrier layer is made of one or more of a metal-coated polyolefin film, an inorganic oxide-coated polyolefin film, an organic-coated polyolefin film, a uniaxially or biaxially stretched single-layer polyethylene film, a uniaxially stretched multi-layer co-extruded polyolefin film, a biaxially stretched multi-layer co-extruded polyolefin film, a multi-layer co-extruded NY / PA polyolefin film, an organic-coated polyolefin barrier film, and an inorganic-coated polyolefin barrier film.

[0010] Preferably, the metal-plated film is metal-plated polyvinyl alcohol.

[0011] Preferably, the metal-coated polyolefin film is aluminum-coated polyethylene or aluminum-coated polypropylene, and the inorganic oxide-coated polyolefin film is aluminum oxide-coated polyethylene or aluminum oxide-coated polypropylene or silicon oxide-coated polyethylene or silicon oxide-coated polypropylene.

[0012] Preferably, the barrier layer has a thickness of 12-150 μm.

[0013] Preferably, the polyolefin heat-sealing layer is a mixture of any two or more of low-density polyethylene, medium-density polyethylene, high-density polyethylene, metallocene polyethylene, homopolypropylene, copolymer polypropylene, and random polypropylene.

[0014] Preferably, the polyolefin heat-sealing layer has a thickness of 50-150 μm.

[0015] Preferably, the polyolefin heat-sealing layer comprises: 20% to 40% metallocene polyethylene; 20% to 30% high-density polyethylene; 10% to 30% low-density polyethylene; and 30% to 50% medium-density polyethylene.

[0016] Preferably, the outer bonding layer comprises: LDPE 50%-100%, HDPE 0%-50%.

[0017] Preferably, the inner bonding layer comprises: LDPE 50% to 100%, HDPE 0% to 50%.

[0018] Furthermore, the present invention provides a method for preparing the composite material packaging of a single polyolefin material, which comprises the following steps: Step 1: Selecting a polyolefin raw material required for processing an outer polyolefin printing layer, and blow molding the outer polyolefin printing layer using a three-layer blow molding device according to the corresponding proportions of the polyolefin raw materials; selecting a polyolefin raw material required for a polyolefin heat sealing layer, and blow molding the polyolefin heat sealing layer using a three-layer blow molding device according to the corresponding proportions of the polyolefin raw materials; Step 2: Processing the barrier layer, the processing method is one or more of the following methods: (1) The film is subjected to single-layer or multi-layer co-extrusion process; or (2) the film is subjected to a uniaxial or biaxial stretching process; Through the above-mentioned stretching process and multi-layer extrusion process, a uniaxially or biaxially stretched single-layer film, a uniaxially stretched multi-layer co-extruded film, a biaxially stretched multi-layer co-extruded film, and a multi-layer co-extruded NY / PA film can be obtained; or (3) evaporating a metal layer, an inorganic oxide layer, or an organic layer on the surface of the film; the above treatment can be used to obtain films such as metal-coated films, inorganic oxide-coated films, and organic-coated films; or (4) coating the surface of the film with an organic substance or an inorganic substance to obtain an organic-coated film or an inorganic-coated film; Step 3: placing adhesive materials between the outer polyolefin printing layer and the barrier layer, and between the barrier layer and the polyolefin heat-sealing layer, respectively, so that the outer polyolefin printing layer, the barrier layer, and the polyolefin heat-sealing layer are compounded in sequence to obtain a composite film; Step 4: Cut the composite film into the required width by a slitting machine.

[0019] Compared with the prior art, the present invention has the following beneficial effects: Compared with traditional aluminum-plastic sheets, the composite material packaging of the present invention made of a single polyolefin material achieves the goal of material singularity, realizes material recycling and reuse, extends the material life cycle, reduces carbon emissions, and reduces the use of metal aluminum elements, which can solve the problem that aluminum-plastic materials are difficult to separate and recycle in the past.

[0020] The single-material composite material packaging of the present invention has stable dimensions and friction coefficient, stable composite strength value and meets the high barrier performance requirements of the client.

[0021] The moisture barrier, oxygen barrier and aroma retention properties of the composite material packaging made of a single polyolefin material of the present invention meet the customer's demand for an ultra-long shelf life, can achieve a long shelf life for the content products, ensure the functionality of the contents, and take into account the demand for single-material de-aluminized packaging products.

[0022] The composite material packaging of the present invention has a low content of non-polyolefin components, which improves the recycling rate and reduces the difficulty of processing and recycling the recycled materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic structural diagram of a composite material package made of a single polyolefin material according to the present invention; In the figure: outer polyolefin printing layer 1; outer adhesive layer 2; barrier layer 3; inner adhesive layer 4; polyolefin heat sealing layer 5. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail in the following embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0025] As attached Figure 1As shown, the composite material packaging of a single polyolefin material in this specific embodiment includes an outer polyolefin printing layer 1, an outer adhesive layer 2, a barrier layer 3, an inner adhesive layer 4 and a polyolefin heat-sealing layer 5 arranged in sequence from the outside to the inside. The outer polyolefin printing layer 1 and the polyolefin heat-sealing layer 5 are selected from any two or more of low-density polyethylene, medium-density polyethylene, high-density polyethylene, metallocene polyethylene, homopolymer polypropylene, copolymer polypropylene, and random polypropylene; the outer adhesive layer 2 includes one of ethylene acrylic acid modified polyethylene, one-component polyurethane, two-component polyurethane, and polyether glue, or the outer adhesive layer 2 includes at least one of LDPE and HDPE; the inner adhesive layer 4 includes one of ethylene acrylic acid modified polyethylene, one-component polyurethane, two-component polyurethane, and polyether glue, or the inner adhesive layer 4 includes at least one of LDPE and HDPE.

[0026] The barrier layer is made of one or more of a metal-plated polyolefin film, an inorganic oxide-plated polyolefin film, an organic-plated polyolefin film, a uniaxially or biaxially stretched single-layer polyethylene film, a uniaxially stretched multi-layer co-extruded polyolefin film, a biaxially stretched multi-layer co-extruded polyolefin film, a multi-layer co-extruded NY / PA polyolefin film, an organic-coated polyolefin barrier film, and an inorganic-coated polyolefin barrier film. In the specific examples of this specific embodiment, the polyolefin is selected from polyethylene.

[0027] In this specific embodiment, the uniaxially stretched multilayer coextruded polyethylene film and the biaxially stretched multilayer coextruded polyethylene film have 3 to 11 layers, and the multilayer coextruded NY / PA polyethylene film has 5 to 11 layers.

[0028] The method for preparing the composite material packaging made of a single polyolefin material comprises the following steps: Step 1: Select the polyolefin raw material required for processing the outer polyolefin printing layer 1, and use a three-layer blow molding device to blow mold the outer polyolefin printing layer according to the corresponding proportion of the polyolefin raw material to obtain the outer polyolefin printing layer; select the polyolefin raw material required for the polyolefin heat sealing layer 5, and use a three-layer blow molding device to blow mold the polyolefin heat sealing layer according to the corresponding proportion of the polyolefin raw material; Step 2: Processing the barrier layer 3, the processing method is one or more of the following methods: (1) The film is subjected to single-layer or multi-layer co-extrusion process; or (2) the film is subjected to a uniaxial or biaxial stretching process; Through the above-mentioned stretching process and multi-layer extrusion process, a uniaxially or biaxially stretched single-layer film, a uniaxially stretched multi-layer co-extruded film, a biaxially stretched multi-layer co-extruded film, and a multi-layer co-extruded NY / PA film can be obtained; or (3) evaporating a metal layer, an inorganic oxide layer, or an organic layer on the surface of the film; the above treatment can be used to obtain films such as metal-coated films, inorganic oxide-coated films, and organic-coated films; or (4) coating the surface of the film with an organic substance or an inorganic substance to obtain an organic-coated film or an inorganic-coated film; Step three: Adhesive materials are arranged between the outer polyolefin printing layer 1 and the barrier layer 3, and between the barrier layer 3 and the polyolefin heat-sealing layer 5, respectively, so that the outer polyolefin printing layer 1, the barrier layer 3, and the polyolefin heat-sealing layer 5 are compounded in sequence to obtain a composite film; in this specific embodiment, one of solvent-free compounding, dry compounding, and extrusion compounding is adopted.

[0029] Step 4: Cut the composite film into the required width by a slitting machine.

[0030] The specific operation and effects of the technical solution of the present invention are described below through a number of specific embodiments.

[0031] As shown in the following table, the material composition and thickness of each layer of the composite material packaging of a single polyolefin material in Examples 1-8 are listed. In the table, as shown in the outer polyolefin printing layer of Example 1: 20% LDPE, 30% MDPE, 40% HDPE, 10% metallocene polyethylene; 100μm. It means that the mass percentage of the components in the outer polyolefin printing layer is: 20% LDPE, 30% MDPE, 40% HDPE, 10% metallocene polyethylene, and the thickness is 100μm.

[0032] Outer polyolefin printed layer Outer bonding layer Barrier layer Inner bonding layer Polyolefin heat seal layer Example 1 20% LDPE, 30% MDPE, 40% HDPE, 10% metallocene polyethylene; 100 μm Two-component polyurethane 3~5g / m22μm Aluminum oxide coated PE; 30μm 80%LDPE20%HDPE20μm 25% metallocene polyethylene, 30% HDPE, 15% LDPE, 30% MDPE; 100μm Example 2 20% LDPE, 30% MDPE, 40% HDPE, 10% metallocene polyethylene; 100 μm Two-component polyurethane 3~5g / m22μm Aluminum-coated PE; 50μm 80%LDPE20%HDPE20μm 25% metallocene polyethylene, 30% HDPE, 15% LDPE, 30% MDPE; 100μm Example 3 20% LDPE, 30% MDPE, 40% HDPE, 10% metallocene polyethylene; 100 μm One-component polyurethane 2~3g / m22μm Aluminum-coated polyvinyl alcohol; 25μm 100%LDPE20μm 25% metallocene polyethylene, 30% HDPE, 15% LDPE, 30% MDPE; 100μm Example 4 40% LDPE, 10% MDPE, 30% HDPE, 20% metallocene polyethylene; 100μm Two-component polyurethane 3~5g / m22μm Double-sided aluminum-coated polyvinyl alcohol; 25μm Two-component polyurethane 3~5g / m22μm 25% metallocene polyethylene, 30% HDPE, 15% LDPE, 30% MDPE; 100μm Example 5 30% LDPE, 20% MDPE, 40% HDPE, 10% metallocene polyethylene; 50μm 100%LDPE 20μm Uniaxially oriented polyethylene film; 12μm 100%LDPE 20μm 40% metallocene polyethylene, 20% HDPE, 10% LDPE, 30% MDPE; 50μm Example 6 20% LDPE, 20% MDPE, 50% HDPE, 10% metallocene polyethylene; 150μm 50%LDPE50%HDPE20μm Biaxially oriented polyethylene film; 25μm 50%LDPE50%HDPE20μm 20% metallocene polyethylene, 25% HDPE, 20% LDPE, 35% MDPE; 150μm Example 7 20% LDPE, 20% MDPE, 40% HDPE, 20% metallocene polyethylene; 70μm 100%LDPE 15μm Multi-layer polyethylene coextruded film; 150μm 100%LDPE 15μm 20% metallocene polyethylene, 20% HDPE, 10% LDPE, 50% MDPE; 70μm Example 8 23% LDPE, 23% MDPE, 42% HDPE, 12% metallocene polyethylene; 80 μm 50%LDPE50%HDPE20μm Co-extruded film of polyamide and polyethylene; 70μm 50%LDPE50%HDPE20μm 20% metallocene polyethylene, 20% HDPE, 30% LDPE, 30% MDPE; 80μm Comparative Example 1 23% LDPE, 23% MDPE, 42% HDPE, 12% metallocene polyethylene; 120 μm 80% modified polyethylene 10% LDPE 10% HDPE 20μm Aluminum foil 12μm 80% modified polyethylene 10% LDPE 10% HDPE 20μm 25% metallocene polyethylene, 30% HDPE, 15% LDPE, 30% MDPE; 58μm Comparative Example 2 23% LDPE, 23% MDPE, 42% HDPE, 12% metallocene polyethylene; 120 μm 100%LDPE30μm Polyvinyl alcohol 70μm 100%LDPE30μm 25% metallocene polyethylene, 30% HDPE, 15% LDPE, 30% MDPE; 58μm Example 1 Step 1: Select 20% LDPE, 30% MDPE, 40% HDPE, and 10% metallocene polyethylene required for processing the outer polyolefin printing layer 1, and use a three-layer blow molding device to blow mold according to the above proportions of the polyolefin raw materials to obtain an outer polyolefin printing layer, and the thickness of the outer polyolefin printing layer 1 is 100 μm; select 25% metallocene polyethylene, 30% HDPE, 15% LDPE, and 30% MDPE required for the polyolefin heat sealing layer 5, and use a three-layer blow molding device to blow mold according to the corresponding proportions of the polyolefin raw materials to obtain a polyolefin heat sealing layer, and the thickness of the polyolefin heat sealing layer 5 is 100 μm; Step 2: Process the barrier layer 3, use polyethylene PE as the base film, and evaporate the oxide aluminum oxide on the surface of the polyethylene PE; use the electroplating box to liquefy the aluminum wire in a vacuum environment, use an electron gun to accelerate the aluminum gas and spray it onto the base film, and quickly cool the material to make a coating material.

[0033] Step three: Adhesive materials are arranged between the outer polyolefin printing layer 1 and the barrier layer 3, and between the barrier layer 3 and the polyolefin heat-sealing layer 5, respectively, so that the outer polyolefin printing layer 1, the barrier layer 3, and the polyolefin heat-sealing layer 5 are compounded in sequence to obtain a composite film; the compounding adopts solvent-free compounding; wherein, the outer adhesive layer adopts two-component polyurethane, and the inner adhesive layer adopts a mixture of LDPE and HDPE.

[0034] Step 4: Cut the composite film into the required width by a slitting machine.

[0035] Example 2 The main difference between Example 2 and Example 1 is that the barrier layer uses aluminum-plated PE with a thickness of 50 μm.

[0036] Example 3 The main difference between Example 3 and Example 1 is that the barrier layer uses aluminum-plated polyvinyl alcohol with a thickness of 25 μm; the outer bonding layer uses single-component polyurethane, and the inner bonding layer uses LDPE.

[0037] Example 4 The main differences between Example 4 and Example 1 are the outer polyolefin printing layer, the barrier layer, and the inner bonding layer, see the table for details.

[0038] Example 5 The layers of Example 5 are different from those of Example 1, please refer to the table for details. And step 3 adopts dry compounding.

[0039] Example 6 The layers of Example 6 are different from those of Example 1, see the table for details. And step 3 adopts extrusion compounding.

[0040] Example 7 Each layer of Example 7 is different from that of Example 1, see the table for details. In this example, a barrier layer film is produced by a 5-layer co-extrusion method. Step 3 uses solvent-free compounding.

[0041] Example 8 The layers of Example 8 and Example 1 are different, see the table for details. Step 2 is to use polyamide and polyethylene as raw materials to obtain a multi-layer polyethylene, polyamide composite co-extruded barrier layer film by a multi-layer co-extrusion process. In this embodiment, a 7-layer co-extrusion method is used, and maleic anhydride modified materials are used to bond polyethylene and polyamide under high temperature conditions. Step 3 uses solvent-free compounding.

[0042] Comparative Example 1 Adopting the extrusion composite production process, using the mixed components of modified polyethylene, LDPE and HDPE as the bonding layer, the aluminum foil and polyethylene are bonded by extrusion bonding. The specific differences of each layer are shown in the table.

[0043] Comparative Example 2 The extrusion composite production process is adopted, and polyethylene and polyvinyl alcohol are used to co-extrude a multi-layer composite film. The specific differences of each layer are shown in the table.

[0044] Table 1 Performance test of examples and comparative examples Oxygen barrier (cm3 / m2.day) Water blocking (g / m2.day) Polyethylene content Example 1 2.2 0.8 99% Example 2 2.2 0.6 99% Example 3 0.2 0.18 95% Example 4 0.15 0.12 95% Example 5 1.5 0.6 100% Example 6 1.2 0.2 100% Example 7 70 0.8 100% Example 8 0.3 0.6 94% Comparative Example 1 0.05 0.08 88% Comparative Example 2 1.2 0.8 92% From the test results in the above table, it can be seen that when the polyethylene content in multiple embodiments reaches more than 98%, the oxygen barrier and water barrier properties can still meet customer needs. In particular, the oxygen barrier coefficient of Example 7 reaches 70, which has excellent performance. Moreover, due to the high polyethylene content, recycling is simple, reducing environmental pollution; although the polyethylene content of Example 8 is 94%, the oxygen barrier and water barrier properties are indeed much higher than similar products on the market. The polyethylene content of Comparative Examples 1-2 is significantly lower than that of Examples 1-8 of the present invention, which is difficult to recycle, and the comprehensive performance of oxygen barrier and water barrier is not ideal. It can be seen that the packaging products made of a single polyolefin material of the present invention are superior to similar products of the prior art in terms of environmental friendliness and performance.

[0045] In summary, although the present invention has been disclosed as above in terms of preferred embodiments, the above preferred embodiments are not intended to limit the present invention. A person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined in the claims.

Claims

1. A composite material packaging made of a single polyolefin material, characterized in that: The package includes an outer polyolefin printing layer, an outer adhesive layer, a barrier layer, an inner adhesive layer and a polyolefin heat-sealing layer which are arranged in sequence from the outside to the inside; the outer adhesive layer includes one of ethylene acrylic acid modified polyethylene, one-component polyurethane, two-component polyurethane, and polyether glue, or the outer adhesive layer includes at least one of LDPE and HDPE; the inner adhesive layer includes one of ethylene acrylic acid modified polyethylene, one-component polyurethane, two-component polyurethane, and polyether glue, or the inner adhesive layer includes at least one of LDPE and HDPE.

2. The composite material packaging made of a single polyolefin material according to claim 1, characterized in that: The outer polyolefin printing layer is a mixture of any two or more of low-density polyethylene, medium-density polyethylene, high-density polyethylene, metallocene polyethylene, homopolymer polypropylene, copolymer polypropylene, and random polypropylene.

3. The composite material packaging made of a single polyolefin material according to claim 2, characterized in that: The thickness of the outer polyolefin printing layer is 50-150 μm.

4. The composite material packaging made of a single polyolefin material according to claim 2 or 3, characterized in that: The outer polyolefin printing layer is composed of low-density polyethylene, medium-density polyethylene, high-density polyethylene, and metallocene polyethylene, and the mass percentages thereof are: 20%-40%, 10%-30%, 30%-50%, and 10%-20%.

5. The composite material packaging made of a single polyolefin material according to claim 1, characterized in that: The barrier layer is one or more of a metal-plated film, an inorganic oxide-plated film, an organic-plated film, a uniaxially or biaxially stretched single-layer film, a uniaxially stretched multilayer co-extruded film, a biaxially stretched multilayer co-extruded film, a multilayer co-extruded NY / PA film, an organic barrier film, and an inorganic barrier film.

6. The composite material packaging made of a single polyolefin material according to claim 5, characterized in that: The barrier layer is made of one or more of a metal-plated polyolefin film, an inorganic oxide-plated polyolefin film, an organic-plated polyolefin film, a uniaxially or biaxially stretched single-layer polyethylene film, a uniaxially stretched multilayer co-extruded polyolefin film, a biaxially stretched multilayer co-extruded polyolefin film, a multilayer co-extruded NY / PA polyolefin film, an organic-coated polyolefin barrier film, and an inorganic-coated polyolefin barrier film.

7. The composite material packaging made of a single polyolefin material according to claim 5, characterized in that: The metal-plated film is metal-plated polyvinyl alcohol.

8. The composite material packaging made of a single polyolefin material according to claim 6, characterized in that: The metal-coated polyolefin film is aluminum-coated polyethylene or aluminum-coated polypropylene, and the inorganic oxide-coated polyolefin film is aluminum oxide-coated polyethylene or aluminum oxide-coated polypropylene or silicon oxide-coated polyethylene or silicon oxide-coated polypropylene.

9. The composite material packaging made of a single polyolefin material according to any one of claims 6 to 8, characterized in that: The thickness of the barrier layer is 12-150 μm.

10. The composite material packaging made of a single polyolefin material according to claim 1, wherein the polyolefin heat-sealing layer is a mixture of any two or more of low-density polyethylene, medium-density polyethylene, high-density polyethylene, metallocene polyethylene, homopolypropylene, copolymer polypropylene, and random polypropylene.

11. The composite material package made of a single polyolefin material according to claim 10, characterized in that: The thickness of the polyolefin heat-sealing layer is 50-150 μm.

12. The composite material packaging made of a single polyolefin material according to claim 10 or 11, characterized in that: The composition of the polyolefin heat-sealing layer is: 20% to 40% metallocene polyethylene; 20% to 30% high-density polyethylene; 10% to 30% low-density polyethylene; and 30% to 50% medium-density polyethylene.

13. The composite material package made of a single polyolefin material according to claim 1, characterized in that: The composition of the outer bonding layer is: LDPE 50%-100%, HDPE 0%-50%.

14. The composite material package made of a single polyolefin material according to claim 1, characterized in that: The composition of the inner bonding layer is: LDPE 50%-100%, HDPE 0%-50%.

15. The method for preparing a composite material package made of a single polyolefin material according to any one of claims 1 to 14, characterized in that: The following steps are involved: Step 1: Selecting a polyolefin raw material required for processing an outer polyolefin printing layer, and blow molding the outer polyolefin printing layer using a three-layer blow molding device according to the corresponding proportions of the polyolefin raw materials; selecting a polyolefin raw material required for a polyolefin heat sealing layer, and blow molding the polyolefin heat sealing layer using a three-layer blow molding device according to the corresponding proportions of the polyolefin raw materials; Step 2: Processing the barrier layer, the processing method is one or more of the following methods: (1) The film is subjected to single-layer or multi-layer co-extrusion process; or (2) the film is subjected to a uniaxial or biaxial stretching process; or (3) evaporation of metal layer, inorganic oxide layer, or organic matter on the surface of the film; or (4) coating the surface of the film with an organic substance or an inorganic substance to obtain an organic-coated film or an inorganic-coated film; Step 3: placing adhesive materials between the outer polyolefin printing layer and the barrier layer, and between the barrier layer and the polyolefin heat-sealing layer, respectively, so that the outer polyolefin printing layer, the barrier layer, and the polyolefin heat-sealing layer are compounded in sequence to obtain a composite film; Step 4: Cut the composite film into the required width by a slitting machine.

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