LLDPE-based mono- and multilayer blown films: Effect of processing parameters on properties

• Published in: Polymer engineering and science Vol. 45; no. 9; pp. 1214 - 1221
• Main Authors: Elkoun, S., Huneault, M.A., McCormick, K., Puterbaugh, F., Kale, L.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.09.2005; Wiley Subscription Services; Society of Plastics Engineers, Inc; Blackwell Publishing Ltd
• Subjects: Applied sciences; Blow moulding; Blown films; Catalysts; Crystallization; Exact sciences and technology; Machinery and processing; Mechanical properties; Moulding; Plastic films; Plastics; Polymer industry, paints, wood; Polymer processing; Production processes; Resins; Technology of polymers; Olefin copolymer; Film; Butylene derivative copolymer; Multiple layer; Mechanical properties; Crystallinity; Experimental study; Property processing relationship; Structure processing relationship; Coextrusion molding; Extrusion blown molding; Impact strength; Ethylene copolymer; Olefin polymer; Tear strength; Linear low density ethylene polymer
• ISSN: 0032-3888; 1548-2634
• DOI: 10.1002/pen.20397

In this study we investigated the effect of processing parameters on the end‐use properties of mono‐ and five‐layer coextruded polyethylene (PE) blown films using three different linear low‐density PE (LLDPE) resins. The three investigated LLDPEs were a conventional Ziegler‐Natta gas phase ethylene‐butene copolymer, and two solution ethylene‐octene resins produced with Ziegler‐Natta and single‐site catalysts. The octene copolymers were produced using NOVA Chemicals Advanced SCLAIRTECH™ process and catalyst technologies. It was found that within the investigated range of processing conditions, tear strength increased in the direction perpendicular to the highest orientation, impact and puncture strength increased with the overall orientation, and the effect of orientation due to shear stresses in the die was negligible because of rapid macromolecular relaxation before crystallization. Finally, it was also shown that due to changes in the size of the crystallites, haze increased with die gap and frost line height (FLH), and decreased as take‐up speed (TUS) increased. POLYM. ENG. SCI., 45:1214–1221, 2005. © 2005 Society of Plastics Engineers