一种高阻隔性多层共挤吹塑膜 High barrier multilayer coextrusion blown film
技术领域 Technical field
本发明涉及一种包装材料, 具体地说, 是一种高阻隔性多层共挤吹塑膜。 The invention relates to a packaging material, in particular to a high-barrier multilayer coextrusion blown film.
背景技术 Background technique
目前, 随着市场的发展和人民生活的不断提高, 人们对商品包装的要求也不断 提出新的要求, 特别是一些冷冻食品、 水产品、 高温蒸煮食品、 名贵药材、 香精香 料、 各种饮料、 酒类、 茶叶、 咖啡、 油性食品、 高精密机械零件及仪器等的包装, 要求包装材料不仅具有良好的防水性能, 还应同时具有良好的阻隔性能, 即防止有 机溶剂渗透的性能。 为满足消费者的要求, 各生产厂家都在致力研究开发新型阻隔 性包装材料及其产品。 At present, with the development of the market and the continuous improvement of people's lives, people have continuously put forward new requirements for the packaging of goods, especially some frozen foods, aquatic products, high-temperature retort foods, valuable medicinal materials, flavors and spices, various beverages, Packaging of alcohol, tea, coffee, oily food, high-precision mechanical parts and instruments, etc. requires that the packaging materials not only have good water resistance, but also have good barrier properties, that is, the ability to prevent the penetration of organic solvents. In order to meet consumer requirements, various manufacturers are committed to research and development of new barrier packaging materials and products.
目前包装领域常用的防水阻隔膜是 PVDC膜和 EVOH膜。 其中 PVDC (聚偏二 氯乙烯, 又名聚偏氯乙烯) 膜有较高的阻隔性, 但由于 PVDC膜的边角料和废弃物 难以回收利用, 焚烧处理时放出 HC1气体, 会造成环境污染。 欧美及台湾地区已转 向使用 EVOH (乙烯-乙烯醇共聚物) 膜, EVOH膜具有无毒、 不污染环境的优点, 但它是通过涂布法制备的, 其操作复杂、 生产效率低。 At present, the waterproof barrier films commonly used in the packaging field are PVDC film and EVOH film. Among them, PVDC (polyvinylidene chloride, also known as polyvinylidene chloride) membranes have high barrier properties, but because the scraps and waste of PVDC membranes are difficult to recycle, HC1 gas is emitted during incineration, which will cause environmental pollution. Europe, the United States, and Taiwan have switched to EVOH (ethylene-vinyl alcohol copolymer) film. EVOH film has the advantages of non-toxicity and environmental pollution, but it is prepared by coating method, which has complicated operation and low productivity.
发明内容 Summary of the invention
本发明的目的是提供一种多层共挤吹塑膜, 它具有良好的防水阻隔性能。 The object of the present invention is to provide a multilayer co-extruded blown film, which has good waterproof barrier properties.
为实现上述目的, 本发明采取以下方案: 本发明采用 PVA (聚乙烯醇) 作为阻 隔层。 在阻隔层的内侧和外侧分别有一层或两层的塑料薄膜层。 To achieve the above object, the present invention adopts the following scheme: The present invention uses PVA (polyvinyl alcohol) as a barrier layer. There are one or two plastic film layers on the inside and the outside of the barrier layer, respectively.
为了说明的方便, 特定义以下名词- 阻隔层的内侧是指共挤吹塑膜与包装物接触的一侧, 阻隔层的外侧是指共挤吹 塑膜与环境接触的另一侧。 For the convenience of explanation, the following terms are specifically defined-the inner side of the barrier layer refers to the side where the coextrusion blown film is in contact with the packaging, and the outer side of the barrier layer refers to the other side where the coextruded blown film is in contact with the environment.
与阻隔层内侧紧邻的一层为内一层, 与内一层紧邻的为内二层, 与内二层紧邻 的为内三层; 与阻隔层外侧紧邻的一层为外一层, 与外一层紧邻的为外二层, 与外 二层紧邻的为外三层。 The layer immediately adjacent to the inside of the barrier layer is the inner layer, the layer immediately adjacent to the inner layer is the inner two layer, and the layer immediately adjacent to the inner two layer is the inner three layer; the layer immediately adjacent to the outside of the barrier layer is the outer layer, and the outer layer The first layer is immediately adjacent to the second outer layer, and the second layer is immediately adjacent to the third outer layer.
可以根据包装物和环境条件的不同, 塑料薄膜层也可以不同, 通常可以是 PE膜 (聚乙烯膜) 、 PP膜 (聚丙烯膜) 、 PA膜 (聚酰胺膜) 、 PC膜 (聚碳酸酯膜) 、 PET (聚对苯二甲酸乙二醇酯) 膜、 PBT (聚对苯二甲酸丁二醇酯) 膜中的一种或几 种。
为了提高本发明各层的粘接强度, 还可以在阻隔层与相邻的塑料薄膜层之间设 有一层粘合剂层。 此时, 内一层和外一层为粘合剂层, 内二层、 内三层、 外二层、 外三层为塑料薄膜层。 Depending on the packaging and environmental conditions, the plastic film layer can also be different, usually PE film (polyethylene film), PP film (polypropylene film), PA film (polyamide film), PC film (polycarbonate Film), PET (polyethylene terephthalate) film, PBT (polybutylene terephthalate) film. In order to improve the bonding strength of each layer of the present invention, an adhesive layer may also be provided between the barrier layer and the adjacent plastic film layer. At this time, the inner layer and the outer layer are adhesive layers, and the inner two layers, the inner three layers, the outer two layers, and the outer three layers are plastic film layers.
粘合剂可以是 EVA (乙烯-乙酸乙烯酯共聚物) 、 EAA (乙烯-丙烯酸共聚物) 、 聚丙烯酸酯、 马来酸酐中的一种或两种。 The binder may be one or two of EVA (ethylene-vinyl acetate copolymer), EAA (ethylene-acrylic acid copolymer), polyacrylate, and maleic anhydride.
PVA阻隔层的厚度为 1~10μιη, 各塑料薄膜层的厚度为 1~20μη, 粘合剂层的厚 度为 1~10μηι。 The thickness of the PVA barrier layer is 1 to 10 μm, the thickness of each plastic film layer is 1 to 20 μη, and the thickness of the adhesive layer is 1 to 10 μm.
本发明的优点是: 阻隔性能好; 层间强度髙, '各层不易分离; 边角料和废弃物 可降解和回收利用, 对环境无毒无害。 The advantages of the present invention are: good barrier performance; interlayer strength is high, 'the layers are not easy to separate; scraps and waste can be degraded and recycled, which is non-toxic and harmless to the environment.
附图概述 Overview of the drawings
图 1为本发明的实施例 1的结构示意图 FIG. 1 is a schematic structural diagram of Embodiment 1 of the present invention
图 2为本发明的实施例 6的结构示意图 FIG. 2 is a schematic structural diagram of Embodiment 6 of the present invention
图 3为本发明的实施例 6的工艺流程图 FIG. 3 is a process flowchart of Embodiment 6 of the present invention
图 4为本发明的实施例 8的结构示意图 FIG. 4 is a schematic structural diagram of Embodiment 8 of the present invention
本发明的实施方式 Embodiments of the invention
实施例 1 Example 1
请参考图 1。 在本实施例中, 高阻隔性多层共挤吹塑膜由外一层 1、 阻隔层 2、 内一层 3共三层构成。阻隔层 2为 PVA, 其厚度为 5μηι。外一层 1是 3μιη 的 ΡΕ膜, 内一层 3是 3μπι的 ΡΡ膜。 Please refer to Figure 1. In this embodiment, the high-barrier multilayer co-extrusion blown film is composed of an outer layer 1, a barrier layer 2, an inner layer 3, and a total of three layers. The barrier layer 2 is PVA, and its thickness is 5 μm. The outer layer 1 is a 3 μm PE film, and the inner layer 3 is a 3 μm PP film.
实施例 2-5 Example 2-5
请参考表 1。 这些实施例也是由外一层 1、 阻隔层 2、 内一层 3共三层构成。 在 这些实^例中, 外一层 1与内一层 3采用了与实施例 1不同的塑料薄膜。 而各层的 厚度与实施例 1相同, 阻隔层 2与实施例 1完全相同。 Please refer to Table 1. These embodiments are also composed of three layers: an outer layer 1, a barrier layer 2, and an inner layer 3. In these examples, the outer layer 1 and the inner layer 3 use a plastic film different from that of the first embodiment. The thickness of each layer is the same as that of the first embodiment, and the barrier layer 2 is completely the same as that of the first embodiment.
表 1 实施例 2-5的结构表 Table 1 Structure of Example 2-5
外一层 1 阻 Pi j层 2 内一层 3 Outer layer 1 Resistor Pi j layer 2 Inner layer 3
-实施例 2 ΡΕ PVA PE 实施例 3 PC PVA PP-Example 2 PE PVA PE Example 3 PC PVA PP
• 实施例 4 PET PVA PBT • Example 4 PET PVA PBT
实施例 5 PBT PVA PET
实施例 6 Example 5 PBT PVA PET Example 6
请参考图 2。 在本实施例中, 高阻隔性多层共挤吹塑膜由外二层 4、 外一层 1、 阻隔层 2、 内一层 3、 内二层 5共五层构成。 外二层 4和内二层 5是塑料薄膜层, 而 外一层 1和内一层 3是粘合剂层。 阻隔层 2为 PVA (聚乙烯醇) , 其厚度为 8μιη。 外二层 4是 3μηι的 PE膜, 内二层 5也是 3μηι的 PE膜。 外一层 1是 Ιμπι的 EVA, 内一层 3也是 Ι μηι的 EVA。 Please refer to Figure 2. In this embodiment, the high-barrier multilayer co-extrusion blown film is composed of a total of five outer layers 4, one outer layer 1, one barrier layer 2, one inner layer 3, and two inner layers 5. Outer layer 4 and inner layer 5 are plastic film layers, while outer layer 1 and inner layer 3 are adhesive layers. The barrier layer 2 is PVA (polyvinyl alcohol), and its thickness is 8 μm. The outer two layers 4 are 3 μm PE films, and the inner two layers 5 are also 3 μm PE films. The outer layer 1 is 1 μm of EVA, and the inner layer 3 is also 1 μm of EVA.
请参考图 3。 制备本实施例时, 一台挤出机挤 PVA阻隔层 2, 另一台挤出机挤 PE塑料薄膜层 4和 5, 第三台挤出机 EVA粘合层 1和 3。 PE的流道在机头中对称地 分为两股, 分别为两个层, 即外二层 4和内二层 5。 同理, EVA的流道也在机头中 对称地分为两股, 分别为两个层, 即外一层 1和内一层 3。 这样做的好处是仅仅使用 了三台挤出机, 就可以成型五层的吹塑膜。 这样的生产过程的另外一个优点是, 无 需加入水或有机溶剂。 Please refer to Figure 3. In the preparation of this example, one extruder extruded the PVA barrier layer 2, the other extruder extruded the PE plastic film layers 4 and 5, and the third extruder EVA adhesive layers 1 and 3. The PE flow path is symmetrically divided into two strands in the machine head, which are respectively two layers, namely the outer two layers 4 and the inner two layers 5. Similarly, the flow channel of EVA is also symmetrically divided into two strands in the nose, which are respectively two layers, namely the outer layer 1 and the inner layer 3. The advantage of this is that with just three extruders, five layers of blown film can be formed. Another advantage of this production process is that no water or organic solvents need to be added.
实施例 7 Example 7
本实施例与实施例 6的区别在于, 外二层 4是 3μιη的 ΡΡ膜, 外一层 1是 Ι μπι 的 ΕΑΑ, 其它各层的材料和厚度与实施例 6相同。 本实施例需要 5台挤出机挤出五 层的吹塑膜。 The difference between this embodiment and Embodiment 6 is that the outer two layers 4 are 3 μm PP films, the outer layer 1 is 1 μm EAA, and the materials and thicknesses of the other layers are the same as those of Embodiment 6. This example requires five extruders to extrude five layers of blown film.
实施例 8 Example 8
本实施例在实施例 6的基础上, 又增加了外三层 6和内三层 7共两层塑料薄膜 层。 这两层都是 3μιη的 ΡΡ膜。 这样, 本实施例由七层构成, 从外到内依次是: 外 三层 6 ( 3μηι的 ΡΡ膜) 、 外二层 4 ( 3μιη的 ΡΕ膜) 、 外一层 1 ( Ι μιη的 EVA) 、 阻隔层 2 ( 8μηι的 PVA ) 、 内一层 3 ( Ι μηι的 EVA) 、 内二层 5 ( 3μηι的 PE膜) 、 内三层 7 ( 3μιη的 ΡΡ膜) 。 In this embodiment, on the basis of Embodiment 6, two outer plastic film layers are added, namely an outer three layer 6 and an inner three layer 7. Both layers are 3 μm PP films. In this way, this embodiment is composed of seven layers, and from the outside to the inside, they are: outer three layers 6 (3 μm PP film), outer two layers 4 (3 μm PE film), outer layer 1 (1 μm EVA), Barrier layer 2 (8 μm PVA), inner layer 3 (1 μm EVA), inner two layers 5 (3 μm PE film), inner three layers 7 (3 μm PP film).
工业应用性 Industrial applicability
实施例 1-8所述的高阻隔性多层共挤吹塑膜, 经长期试验和试用, 都具有优良的 防水性能和阻隔性能, 且制备简单, 无毒无污染。
The high-barrier multilayer co-extruded blown film described in Examples 1-8, after long-term tests and trials, both have excellent waterproof properties and barrier properties, and are simple to prepare, non-toxic and pollution-free.