AZEVEDO, Nayfson Araújo de.; ALVES, Tatianny Soares.; CANEDO, Eduardo Luis.; CARVALHO, Laura Hecker de.
Resumo:
This work deals with mechanical and barrier properties of polyolefin films. Sodium bentonite (1%) was added
to three polyolefin matrices (PP, HDPE and LDPE) and films prepared by single screw extrusion with a flat
die. The extruder was operated under appropriate conditions for each of the matrices. The influence of
bentonite addition on the tensile and water vapour permeability of these films was investigated. Tests were
conducted under controlled humidity and temperature. Tensile properties of polymer films were hardly
affected (elongation at break) or reduced (tensile strength) by bentonite incorporation, which was attributed
to poor polymer/filler interfacial adhesion. Water vapor permeability of the films investigated increased in the
order PP < HDPE < LDPE. Bentonite addition led to increased film permeability.