Influence of compatibilizer on morphology and mechanical properties of LLDPE/NR blends produced by blown film and chill roll cast film extrusion

Abstract

The addition of Natural Rubber (NR) into Linear Low Density Polyethylene (LLDPE) significantly improved processability of LLDPE resins as evidenced by the increase of draw ratio (DR) and blow up ratio (BUR) which directly relate to the ultimate melt strength of LLDPE. Maleic anhydride (MA) was added in 1-5 wt% to in-situ compatibilize the blend. By using this technique the melt viscosity, morphology and mechanical properties of LLDPE/NR blends were affected. The biaxial orientation in blown film and uniaxial orientation in chill roll cast film processes were investigated by infrared dichoism. The crystalline orientation (fc) was higher than amorphous orientation (fam). Moreover, the molecular orientation strongly affected the mechanical properties of the film; such as tear resistance, tensile strength, impact strength. Tear resistance and impact strength also increased as NR loading increased; whereas, the tensile strength of films decreased.