Five-layer co-extruded polyethylene film for powder-liquid double chamber bag and preparation method thereof

Abstract

The present invention discloses a five-layer co-extruded polyethylene film for a powder-liquid double chamber bag and a preparation method thereof. The film comprises a low-density polyethylene base film layer, a linear low-density polyethylene base film layer, a high-density polyethylene base film layer, a linear low-density polyethylene base film layer and a low-density polyethylene base film layer, which are arranged in sequence from the outside to the inside. The preparation method comprises (1) weighing raw materials according to the raw material formula of each film layer and mixing and granulating; (2) weighing low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, high-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and low-density polyethylene masterbatch into a hopper and plasticizing, and then co-extruding the five layers and biaxially stretching to obtain a film. The five-layer co-extruded polyethylene film of the present invention has the advantages of safe use, environmental protection, low cost, etc. The preparation method is environmentally friendly, the process is simple and controllable, and it is easy to realize industrial application.

Description

Technical Field

[0001] The invention belongs to the field of pharmaceutical soft packaging, and in particular relates to a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag and a preparation method thereof. Background Art

[0002] Flexible packaging bags have the advantages of being easy to carry, convenient to store, small space occupation, good sealing and good barrier properties, and are increasingly widely used in pharmaceutical packaging. Among them, infusion bags account for a relatively high proportion of pharmaceutical flexible packaging. Traditional packaging is to package pharmaceutical powders and solvents separately with different materials and containers. Usually, the solvent is directly packaged in the infusion bag, and the pharmaceutical powder is packaged in a glass bottle or plastic bottle. When used, the powder and the medicine are mixed in proportion and injected into the infusion bag. This form is not very convenient in outdoor medical rescue such as field medical expeditions, earthquake relief and disaster relief. Therefore, people developed a powder-liquid double-chamber bag, in which one chamber of the bag is pre-filled with powder medicine, and the other chamber is pre-filled with solvent. Before use, the two chambers are separated by hot pressing "weak welding". When in use, extrusion pressure is applied to the outer surfaces of the two chambers to open the "weak welding rod", and the liquid solvent flows into the powder chamber through the opened weak welding area. Then, by shaking, the powder medicine is fully dissolved in the bag, and the dispensing is completed. The entire dispensing process is carried out in a closed bag. Compared with traditional dispensing methods, it has the advantages of high efficiency, easy use, and avoidance of secondary pollution. It can be conveniently and safely used in hospital clinics and even in harsh outdoor environments. Therefore, the powder-liquid double-chamber bag has become the preferred packaging solution for more and more pharmaceuticals.

[0003] However, since the powder-liquid double chamber bag was first successfully developed abroad, strict patent protection has been implemented in my country. my country's pharmaceutical flexible packaging bag-making enterprises can only purchase powder-liquid double chamber bag film from abroad at a relatively high price to make powder-liquid double chamber bags. In order to make the powder-liquid double chamber bag play a greater role in my country's pharmaceutical packaging and medical activities, and at the same time achieve the goal of reducing costs and increasing efficiency, it is of great significance to research and develop a preparation method for the powder-liquid double chamber bag film with my country's independent intellectual property rights. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a five-layer co-extruded polyethylene film for powder-liquid double-chamber bags and a preparation method thereof which is safe to use, environmentally friendly, low in cost, simple and controllable in preparation, and easy to realize industrial application.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions.

[0006] A five-layer co-extruded polyethylene film for a powder-liquid double chamber bag, comprising a low-density polyethylene base film layer, a linear low-density polyethylene base film layer, a high-density polyethylene base film layer, a linear low-density polyethylene base film layer and a low-density polyethylene base film layer arranged in sequence from outside to inside, wherein the thickness of the low-density polyethylene base film layer is 0.1 μm to 10 μm, the thickness of the linear low-density polyethylene base film layer is 0.1 μm to 10 μm, and the thickness of the high-density polyethylene base film layer is 10 μm to 100 μm;

[0007] The low-density polyethylene base film layer is made of the following raw materials by mass fraction:

[0008]

[0009]

[0010] The linear low-density polyethylene base film layer is made of the following raw materials by mass fraction:

[0011]

[0012] The high-density polyethylene base film layer is made of the following raw materials by mass fraction:

[0013]

[0014] As a general technical concept, the present invention also provides a method for preparing the above-mentioned five-layer co-extruded polyethylene film for the powder-liquid double-chamber bag, comprising the following steps:

[0015] (1) weighing raw materials according to the above-mentioned raw material formulas of each film layer respectively and mixing them evenly, and preparing low-density polyethylene masterbatch, linear low-density polyethylene masterbatch and high-density polyethylene masterbatch by extrusion granulation;

[0016] (2) weighing low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, high-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and low-density polyethylene masterbatch according to a mass ratio of 0.1-10:0.1-10:10-100:0.1-10:0.1-10 respectively and putting them into different hoppers for plasticization;

[0017] (3) The plasticized material is extruded into a thick film blank by a five-layer co-extrusion method, and then biaxially stretched to obtain a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag.

[0018] In the above-mentioned method for preparing the five-layer co-extruded polyethylene film for the powder-liquid double-chamber bag, preferably, in step (3), the thickness of the thick film blank is 500μm to 1000μm, and the thickness of the five-layer co-extruded polyethylene film for the powder-liquid double-chamber bag is 20μm to 100μm.

[0019] In the present invention, the density of low-density polyethylene is 0.91-0.93 g / cm 3 .

[0020] In the present invention, the density of the linear low-density polyethylene is 0.918-0.935 g / cm 3 .

[0021] In the present invention, the density of high-density polyethylene is 0.941-0.960 g / cm 3 .

[0022] Compared with the prior art, the advantages of the present invention are:

[0023] 1. The five-layer co-extruded polyethylene film for powder-liquid double-chamber bag of the present invention has the advantages of safe use, environmental protection, low cost, etc. The raw material formula fully utilizes the good mutual adhesion between different types of low-density polyethylene, and the melting temperature changes in a gradient, which meets the requirements of weak welding. The thickness of the low-density polyethylene base film layer, the linear low-density polyethylene base film layer, and the high-density polyethylene base film layer is a key parameter for determining whether the weak welding strength meets the use requirements. The five-layer co-extruded polyethylene film of the present invention can be made into a powder-liquid double-chamber bag by heat sealing.

[0024] 2. The preparation method of the present invention has the advantages of environmental protection, low cost, simple and controllable process, and easy industrial application. Among them, the mass ratio of low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, high-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and low-density polyethylene masterbatch is an important technical feature. The mass ratio is a key parameter that determines the thickness ratio, and the thickness ratio is a key parameter that determines the weak weld strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag in Example 1 of the present invention.

[0026] Legend:

[0027] 1. Low-density polyethylene base film layer; 2. Linear low-density polyethylene base film layer; 3. High-density polyethylene base film layer. DETAILED DESCRIPTION

[0028] The present invention is further described below in conjunction with the accompanying drawings and specific preferred embodiments, but the protection scope of the present invention is not limited thereby. The materials and instruments used in the following embodiments are all commercially available.

[0029] Example 1

[0030] A five-layer co-extruded polyethylene film for a powder-liquid double chamber bag of the present invention, such as Figure 1As shown, it includes a low-density polyethylene base film layer 1, a linear low-density polyethylene base film layer 2, a high-density polyethylene base film layer 3, a linear low-density polyethylene base film layer 2 and a low-density polyethylene base film layer 1 arranged in sequence from the outside to the inside. It can also be considered that the two outermost layers are low-density polyethylene base film layers 1, the two sub-outer layers are linear low-density polyethylene base film layers 2, and the middle layer is a high-density polyethylene base film layer 3. The thickness of the low-density polyethylene base film layer 1 is 0.1 μm, the thickness of the linear low-density polyethylene base film layer 2 is 0.1 μm, and the thickness of the high-density polyethylene base film layer 3 is 19.6 μm.

[0031] In this embodiment, the low-density polyethylene base film layer 1 is made of the following raw materials in mass fraction:

[0032]

[0033] In this embodiment, the linear low-density polyethylene base film layer 2 is made of the following raw materials in mass fraction:

[0034]

[0035] In this embodiment, the high-density polyethylene base film layer 3 is made of the following raw materials in mass fraction:

[0036]

[0037] A method for preparing a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag of this embodiment comprises the following steps:

[0038] (1) The raw materials of the above layers are mixed uniformly, extruded and granulated to prepare low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and high-density polyethylene masterbatch;

[0039] (2) Weigh low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, high-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and low-density polyethylene masterbatch in a mass ratio of 0.1:0.1:19.6:0.1:0.1, and put them into corresponding hoppers for plasticization. The plasticization can be carried out by conventional plasticization methods;

[0040] (3) The plasticized material enters a five-layer co-extrusion composite die head, is co-extruded to form a thick film blank, and then is bidirectionally (longitudinal and transverse) stretched to obtain a five-layer co-extruded polyethylene film with a thickness of 20 μm for a powder-liquid double-chamber bag.

[0041] Example 2

[0042] A five-layer co-extruded polyethylene film for a powder-liquid double chamber bag of the present invention, such as Figure 1As shown, it includes a low-density polyethylene base film layer 1, a linear low-density polyethylene base film layer 2, a high-density polyethylene base film layer 3, a linear low-density polyethylene base film layer 2 and a low-density polyethylene base film layer 1, which are arranged in sequence from the outside to the inside. The thickness of the low-density polyethylene base film layer 1 is 10 μm, the thickness of the linear low-density polyethylene base film layer 2 is 10 μm, and the thickness of the high-density polyethylene base film layer 3 is 60 μm.

[0043] In this embodiment, the low-density polyethylene base film layer 1 is made of the following raw materials in mass fraction:

[0044]

[0045] In this embodiment, the linear low-density polyethylene base film layer 2 is made of the following raw materials in mass fraction:

[0046]

[0047] In this embodiment, the high-density polyethylene base film layer 3 is made of the following raw materials in mass fraction:

[0048]

[0049]

[0050] A method for preparing a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag of this embodiment comprises the following steps:

[0051] (1) The raw materials of the above layers are mixed uniformly, extruded and granulated to prepare low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and high-density polyethylene masterbatch;

[0052] (2) Weighing low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, high-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and low-density polyethylene masterbatch in a mass ratio of 10:10:60:10:10, and placing them in corresponding hoppers for plasticization;

[0053] (3) The plasticized material enters a five-layer co-extrusion composite die head, is co-extruded to form a thick film blank, and then is biaxially stretched to obtain a five-layer co-extruded polyethylene film with a thickness of 100 μm for a powder-liquid double-chamber bag.

[0054] Example 3

[0055] A five-layer co-extruded polyethylene film for a powder-liquid double chamber bag of the present invention, such as Figure 1As shown, it includes a low-density polyethylene base film layer 1, a linear low-density polyethylene base film layer 2, a high-density polyethylene base film layer 3, a linear low-density polyethylene base film layer 2 and a low-density polyethylene base film layer 1, which are arranged in sequence from the outside to the inside. The thickness of the low-density polyethylene base film layer 1 is 1 μm, the thickness of the linear low-density polyethylene base film layer 2 is 1 μm, and the thickness of the high-density polyethylene base film layer 3 is 26 μm.

[0056] In this embodiment, the low-density polyethylene base film layer 1 is made of the following raw materials in mass fraction:

[0057]

[0058] In this embodiment, the linear low-density polyethylene base film layer 2 is made of the following raw materials in mass fraction:

[0059]

[0060] In this embodiment, the high-density polyethylene base film layer 3 is made of the following raw materials in mass fraction:

[0061]

[0062] A method for preparing a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag of this embodiment comprises the following steps:

[0063] (1) The raw materials of the above layers are mixed uniformly, extruded and granulated to prepare low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and high-density polyethylene masterbatch;

[0064] (2) Weighing low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, high-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and low-density polyethylene masterbatch in a mass ratio of 1:1:26:1:1, and placing them in corresponding hoppers for plasticization;

[0065] (3) The plasticized material enters a five-layer co-extrusion composite die head, is co-extruded to form a thick film blank, and then is biaxially stretched to obtain a five-layer co-extruded polyethylene film with a thickness of 30 μm for a powder-liquid double-chamber bag.

[0066] Example 4

[0067] A five-layer co-extruded polyethylene film for a powder-liquid double chamber bag of the present invention, such as Figure 1 As shown, it includes a low-density polyethylene base film layer 1, a linear low-density polyethylene base film layer 2, a high-density polyethylene base film layer 3, a linear low-density polyethylene base film layer 2 and a low-density polyethylene base film layer 1 arranged in sequence from the outside to the inside. The thickness of the low-density polyethylene base film layer 1 is 1 μm, the thickness of the linear low-density polyethylene base film layer 2 is 1 μm, and the thickness of the high-density polyethylene base film layer 3 is 21 μm.

[0068] In this embodiment, the low-density polyethylene base film layer 1 is made of the following raw materials in mass fraction:

[0069]

[0070] In this embodiment, the linear low-density polyethylene base film layer 2 is made of the following raw materials in mass fraction:

[0071]

[0072] In this embodiment, the high-density polyethylene base film layer 3 is made of the following raw materials in mass fraction:

[0073]

[0074] A method for preparing a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag of this embodiment comprises the following steps:

[0075] (1) The raw materials of the above layers are mixed uniformly, extruded and granulated to prepare low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and high-density polyethylene masterbatch;

[0076] (2) Weighing low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, high-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and low-density polyethylene masterbatch in a mass ratio of 1:1:21:1:1, and placing them in corresponding hoppers for plasticization;

[0077] (3) The plasticized material enters a five-layer co-extrusion composite die head, is co-extruded to form a thick film blank, and then is biaxially stretched to obtain a five-layer co-extruded polyethylene film with a thickness of 25 μm for a powder-liquid double-chamber bag.

[0078] Example 5

[0079] A five-layer co-extruded polyethylene film for a powder-liquid double chamber bag of the present invention, such as Figure 1 As shown, it includes a low-density polyethylene base film layer 1, a linear low-density polyethylene base film layer 2, a high-density polyethylene base film layer 3, a linear low-density polyethylene base film layer 2 and a low-density polyethylene base film layer 1, which are arranged in sequence from the outside to the inside. The thickness of the low-density polyethylene base film layer 1 is 5 μm, the thickness of the linear low-density polyethylene base film layer 2 is 5 μm, and the thickness of the high-density polyethylene base film layer 3 is 30 μm.

[0080] In this embodiment, the low-density polyethylene base film layer 1 is made of the following raw materials in mass fraction:

[0081]

[0082]

[0083] In this embodiment, the linear low-density polyethylene base film layer 2 is made of the following raw materials in mass fraction:

[0084]

[0085] In this embodiment, the high-density polyethylene base film layer 3 is made of the following raw materials in mass fraction:

[0086]

[0087] A method for preparing a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag of this embodiment comprises the following steps:

[0088] (1) The raw materials of the above layers are mixed uniformly, extruded and granulated to prepare low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and high-density polyethylene masterbatch;

[0089] (2) Weighing low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, high-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and low-density polyethylene masterbatch in a mass ratio of 5:5:30:5:5, and placing them in corresponding hoppers for plasticization;

[0090] (3) The plasticized material enters a five-layer co-extrusion composite die head, is co-extruded to form a thick film blank, and then is biaxially stretched to obtain a five-layer co-extruded polyethylene film with a thickness of 50 μm for a powder-liquid double-chamber bag.

[0091] The above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as above in the preferred embodiment, it is not used to limit the present invention. Any technician familiar with the art can make many possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention, still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A five-layer co-extruded polyethylene film for a powder-liquid double chamber bag, characterized in that: The invention comprises a low-density polyethylene base film layer (1), a linear low-density polyethylene base film layer (2), a high-density polyethylene base film layer (3), a linear low-density polyethylene base film layer (2) and a low-density polyethylene base film layer (1) which are arranged in sequence from the outside to the inside, wherein the thickness of the low-density polyethylene base film layer (1) is 0.1 μm to 10 μm, the thickness of the linear low-density polyethylene base film layer (2) is 0.1 μm to 10 μm, and the thickness of the high-density polyethylene base film layer (3) is 10 μm to 100 μm; The low-density polyethylene base film layer (1) is made of the following raw materials in mass fractions: The linear low-density polyethylene base film layer (2) is made of the following raw materials in mass fractions: The high-density polyethylene-based film layer (3) is made of the following raw materials in terms of mass fraction:

2. A method for preparing a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag as claimed in claim 1, characterized in that: The following steps are involved: (1) weighing the raw materials of each film layer according to the raw material formula of claim 1, mixing them uniformly, and preparing low-density polyethylene masterbatch, linear low-density polyethylene masterbatch and high-density polyethylene masterbatch by extrusion granulation; (2) weighing low-density polyethylene masterbatch, linear low-density polyethylene masterbatch, high-density polyethylene masterbatch, linear low-density polyethylene masterbatch, and low-density polyethylene masterbatch according to a mass ratio of 0.1-10:0.1-10:10-100:0.1-10:0.1-10 respectively and putting them into different hoppers for plasticization; (3) The plasticized material is extruded into a thick film blank by a five-layer co-extrusion method, and then biaxially stretched to obtain a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag.

3. The method for preparing a five-layer co-extruded polyethylene film for a powder-liquid double-chamber bag according to claim 2, characterized in that: In step (3), the thickness of the thick film blank is 500 μm to 1000 μm, and the thickness of the five-layer co-extruded polyethylene film used for the powder-liquid double-chamber bag is 20 μm to 100 μm.

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