Ternary Blended Polyethylene Films: A Study on Its Mechanical and Thermal Properties

Abstract

Six film samples of varying compositions of low-density polyethylene (LDPE) (40–70 wt%) and high-density polyethylene (HDPE) (5–35 wt%) having a fixed percentage of linear low-density polyethylene (LLDPE) at 25 wt% have been extruded by melt blending in a single-screw extruder (L/D ratio=20:1) of uniform thickness of 2 (mil). The mechanical and thermal properties of these films were evaluated. The tensile strength has been found to increase up to 25 wt% HDPE addition in LDPE and then decreased, whereas the elongation at break decreased up to 20 wt% addition of HDPE in the blend and then increased up to 55 wt% addition. The impact failure load increased with the HDPE content in the blend up to 25 wt% addition and then decreased. The initial degradation temperature has been evaluated for a blend composition having LDPE:LLDPE:HDPE=50:25:25 from thermogravimetric analysis and it was found to be 310°C. Differential scanning calorimetric analysis was also performed for all composition ranges to investigate the effect of melting temperature with HDPE content in LDPE. The morphology of this blend composition was investigated by scanning electron microscopic analysis.