Polymer Engineering and Science, Vol.35, No.23, 1878-1883, 1995
Performance of Reprocessed Multilayer LDPE/Nylon-6 Film
Multilayer LDPE/nylon-6 films with an overall content of 71 wt% LDPE, 24 wt% nylon-6, and 5 wt% PE-based tie-layer adhesive were reprocessed under both minimal and extensive mixing conditions. Thermal and mechanical properties, oxygen and water vapor permeability, and morphology of the reprocessed samples were determined. The modulus and yield stress of the reprocessed films fell between those of the pure homopolymers, whereas percent elongation at break and energy-to-break for all reprocessed films were less than those of the homopolymers. In minimally reprocessed film, layering of LDPE (low-density polyethylene) and nylon-6 was retained, whereas in extensively mixed samples, nylon-6 domains were spherical and ranged from 0.2 to 7 mu m. Minimally reprocessed film exhibited good O-2 and H2O vapor barrier properties, whereas extensively-mixed samples had poor barrier properties. Properties of well-mixed blends prepared both with and without adhesive showed that 5 wt% adhesive did not compatibilize the LDPE and nylon-6 components.
Keywords:LOW-DENSITY POLYETHYLENE;IMMISCIBLE BLENDS;RHEOLOGICAL PROPERTIES;POLYAMIDE BLENDS;PHASE MORPHOLOGY;POLYMER BLENDS;NYLON-6;PHOTOOXIDATION;PERMEABILITY;BARRIERS