Oriented structure of PP/LLDPE multilayer and blends films

Polypropylene/linear low-density polyethylene (PP/LLDPE) multilayer and blends blown films are investigated in terms of crystalline morphology and orientation. The crystalline structures were probed using microscopy, infrared trichroism and X-ray pole figures. Two different PPs were used, one was a homopolymer and the other was a copolymer. Similar orientation characteristics were observed for both PP components in the blends and multilayer films, the PE component, however, showed very different structure, especially for the crystalline a- and b-axes orientation. The row-nucleated structure, epitaxial crystallization and transcrystallization observed in the films are discussed.