Preparation of Polymer Blends Between Poly (L-Lactic Acid), Poly (Butylene Succinate-Co-Adipate) and Poly (Butylene Adipate-Co-Terephthalate) for Blow Film Industrial Application

The preparation of polymer blends of poly (lactic acid) (PLA), Poly(butylene-succinate-co-adipate)(PBSA) and poly)butylene adipate-co-terephthalate((PBAT) were studied with the objectives to apply to blown film extrusion method. The blends were prepared using twin-screw extruder. The ratio of PLA and PBSA was fixed at 80/20 and the PBAT content was investigated with 0, 10, 20, 30, 40 and 50 wt%. The speed of screw was 80 rpm with the die temperatures of 220, 200, and 180 °C. It was found that the melt flow index)MFI(and tensile strength of blends decreased with increasing amount of PBAT, whereas the percentage strain showed contrastive results. The maximum tensile strength and impact strength were reached with the blend of equal amount 20 wt% of PBAT. Then, the correspondent condition was used in the blown film extrusion process. The morphology investigation using scanning electronic microscopy)SEM(of PLA/PBSA/PBAT blends showed an excellent compatibility between the three polymers.