The Effect of Extrusion Processing Conditions on the Thermal and Mechanical Performance of Extrusion Cast Metallocene Polyethylene Films

Cast extruded films were prepared from a range of mPE resins with various co-monomer types (hexene, octene), using different chill roll temperatures from 30 to 60°C. Mechanical analysis showed that the tensile modulus of the films increased with progressive increase in chill roll temperature. DSC analysis showed increases in crystallinity with increasing quench temperature and decreasing MFI. Rheological and molecular weight distribution analysis showed that activation energies of flow for mPE (18-28kJ/mol) were low, this is attributable to the narrower polydispersity of mPE (2.1-3.1) compared to the wider distribution of conventional polyethylenes (4.0-5.0)