Multilayer structures using reprocessed coextruded LLDPE/tie/PA-6 films

Abstract

Five-layer coextruded films: linear low density polyethylene (LLDPE)/tie/Polyamide-6 (PA6)/tie/LLPDE were reprocessed by melt mixing and their thermal and rheological properties were determined. The morphology of the blend was analyzed with SEM after PA6 extraction. The T-peel strength of two-layer laminated films: Blend/PA6 was evaluated. Three-layer coextruded films: LLDPE/Blend/LLDPE were prepared and the effect of the reprocessed blend content and layer thickness on the mechanical properties was analyzed. Oxygen and water vapor permeability of the coextruded films were also determined. The linear low density polyethylene-grafted maleic anhydride (LLDPEgMA) used as adhesive in the five-layer film has a slight effect in reducing the crystallinity of the LLDPE. A reduction in mechanical properties and oxygen permeability, as well as an increase in water vapor transmission rate (WVTR) were observed when increasing the reprocessed blend content in the multilayer film. © 2011, Walter de Gruyter GmbH & Co. All rights reserved.