Summary of the invention
The object of the present invention is to provide the good Biaxially oriented polypropylene adhesive-free film of a kind of paracentesis resistance.
To achieve these goals, technical scheme of the present invention is: Biaxially oriented polypropylene adhesive-free film, it is characterized in that: it is made up of top layer, sandwich layer and inferior top layer, and sandwich layer is between top layer and time top layer, and coextrusion is adopted on top layer, sandwich layer and inferior top layer after biaxial tension and being integral;
The material on described top layer is made up of low density polyethylene (LDPE), antitack agent and slipping agent, and the shared mass percent of each component is: low density polyethylene (LDPE) 90%, antitack agent 5%, slipping agent 5%;
The material of described sandwich layer is made up of low density polyethylene (LDPE), metallocene PE and ethylene-propylene diene copolymer, and the shared mass percent of each component is: low density polyethylene (LDPE) 50%, metallocene PE 40%, ethylene-propylene diene copolymer 10%;
The material on described top layer is made up of ethene-vinyl acetate vinegar copolymer (EVA), paraffin wax, hydrogenation resin, low density polyethylene (LDPE) and antioxidant, and the shared mass percent of each component is: ethene-vinyl acetate vinegar copolymer (EVA) 80%, paraffin wax 5%, hydrogenation resin 10%, low density polyethylene (LDPE) 4.5%, antioxidant 0.5%;
The material on top layer: the material of sandwich layer: the mass ratio of the material on inferior top layer is 1: 1: 1.
The invention has the beneficial effects as follows: paracentesis resistance is good.
The specific embodiment
Embodiment 1:
As shown in Figure 1, Biaxially oriented polypropylene adhesive-free film, it is made up of top layer 1, sandwich layer 2 and inferior top layer 3, sandwich layer 2 is between top layer 1 and time top layer 3, coextrusion are adopted on top layer 1, sandwich layer 2 and inferior top layer 3 after biaxial tension and be integral (extrusion temperature is 180-230 ℃, adopts existing co-extrusion, stretch processes);
The material on described top layer 1 is made up of low density polyethylene (LDPE), antitack agent and slipping agent, and the shared mass percent of each component is: low density polyethylene (LDPE) 90%, antitack agent 5%, slipping agent 5%;
The material of described sandwich layer 2 is made up of low density polyethylene (LDPE), metallocene PE and ethylene-propylene diene copolymer, and the shared mass percent of each component is: low density polyethylene (LDPE) 50%, metallocene PE 40%, ethylene-propylene diene copolymer 10%;
The material on described top layer 3 is made up of ethene-vinyl acetate vinegar copolymer (EVA), paraffin wax, hydrogenation resin, low density polyethylene (LDPE) and antioxidant, and the shared mass percent of each component is: ethene-vinyl acetate vinegar copolymer (EVA) 80%, paraffin wax 5%, hydrogenation resin 10%, low density polyethylene (LDPE) 4.5%, antioxidant 0.5%;
The material on top layer 1: the material of sandwich layer 2: the mass ratio of the material on inferior top layer 3 is 1: 1: 1.
The density of described low density polyethylene (LDPE) is 0.925g/cm
3Below.
Described antitack agent is SiO
2
Described slipping agent is that { (EBS) English name: Ethylenebis-stearamide is commonly called as ethylene bis stearamide: brightener, dispersant, molecular formula: C
38H
76N
2O
2.
Described antioxidant is phosphite.
Preparation method of the present invention is: the raw material of apolegamy is sent into extruder be processed into melt, melt becomes sheet by curtain coating casting sheet co-extrusion, sheet becomes film through biaxial tension, film becomes female film through sided corona treatment or flame treatment, parent roll cuts into the Biaxially oriented polypropylene adhesive-free film finished product at last through Ageing Treatment.
The hot combined temp of Biaxially oriented polypropylene adhesive-free film of the present invention is low, is 60-95 ℃.
Biaxially oriented polypropylene adhesive-free film of the present invention is carried out paracentesis resistance experiment: with the endurable thorn tester Biaxially oriented polypropylene adhesive-free film of the present invention that punctures, 15N can reach 21 punctures and do not break; Under the similarity condition, and existing bidirectional stretching polypropylene film puncture 5 times and breaking; Puncture time of the present invention is many, the paracentesis resistance good (good toughness) of Biaxially oriented polypropylene adhesive-free film of the present invention is described, the long service life of product.
Embodiment 2:
Substantially the same manner as Example 1, difference is: described antitack agent is a talcum, and described slipping agent is a fatty acid ester.
Embodiment 3:
Substantially the same manner as Example 1, difference is: described antitack agent is a talcum, and described slipping agent is an oleamide, and described antioxidant is phenol (all be applicable to the present invention).
The present invention cited each raw material (comprising different molecular weight, different manufacturers) can both be realized the present invention, does not enumerate embodiment one by one at this.