Optimization of PE/Binder/PA extrusion blow-molded films. I. Heat sealing ability improvement using PE/EVA blends

• Published in: Journal of applied polymer science Vol. 99; no. 3; pp. 974 - 985
• Main Authors: Poisson, C., Hervais, V., Lacrampe, M. F., Krawczak, P.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 05.02.2006; Wiley
• Subjects: Applied sciences; blends; blown film; Bonding and welding; Chemical and Process Engineering; Chemical Sciences; coextrusion; Condensed Matter; Engineering Sciences; Exact sciences and technology; heat sealing; Machinery and processing; Materials; Materials Science; mechanical properties; optical properties; peeling; Physics; Plastics; Polymer industry, paints, wood; Polymers; tearing; Technology of polymers; Nylon; Film; Property processing relationship; Optimization; Molecular orientation; peeling; Welded joint; Coextrusion molding; Optical properties; Olefin polymer; Technological properties; blends; Polyethylene; Polymer blends; blown film; heat sealing; Multiple layer; Mechanical properties; Crystallinity; Experimental study; Structure processing relationship; EVA; Extrusion blown molding; tearing; coextrusion; Hot welding; Weldability
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.22405

The optimization of three‐layer films (PE/binder/PA) manufactured by extrusion blow molding presents significant industrial challenges. The main issue consists in combining use properties (e.g., impermeability to water steam and oxygen, welding properties) with high mechanical, optical, and adhesion performances, while maintaining cost‐effectiveness. This article shows that the introduction of EVA in the PE layer improves the heat sealing ability and optical properties without degradation of the mechanical and adhesion performances. In the most favorable case, this modification leads to a 40% reduction of the heat sealing time, the other performances remaining either identical or higher. This leads to cost reduction of this manufacturing step while improving the flexibility of the process (wider process temperature window). The properties modifications observed can be explained by microstructure modifications (crystallinity, orientation, and molecular mobility). © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 974–985, 2006