Effect of Plasticizers on Tapioca Starch-Based Biofilms via Blown Film Extrusion Process

In this study, a series of tapioca starch-based low density polyethylene (LDPE) biofilms were prepared via extrusion process and further using blown film extrusion with various contents of starch. Various contents of glycerol and palm oil based olein as plasticizers, both ranging from 5 wt% to 20 wt% were added to blends. The starch-based LDPE blends were undergo the melt flow index analysis to study its processability before further process by film blowing extrusion. Both film blowing ability and melt indexes displayed the effect of both plasticizers in starch-based LDPE blends. Starch based LDPE biofilms with addition of 5 wt% palm oil based glycerin show large influence on the shear viscous properties of starch polymer melts compared to glycerol. Palm oil based glycerin would decrease the viscosity of starch polymer melt since it can decrease the polymer entanglement density and increase the ease of disentanglement.