Preparation of poly(lactide)/poly(butylene adipate-co-terephthalate) blend films using a solvent casting method and their food packaging application

Blend films with poly(lactide) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) were prepared using a solvent-casting method to modify the property of PLA film, and their properties were evaluated. FT-IR and DSC test results indicated that PLA is highly compatible with PBAT to form homogeneous blend films. The flexibility of PLA films increased significantly by blending small amount of PBAT without significant decrease in mechanical properties. Even the blend film with small amount of PBAT, 3.92 g of PLA with 0.08 g of PBAT (PLA₉₈/PBAT₂), exhibited UV screening effect without sacrificing transparency. The water vapor permeability and oxygen transfer rate of the blend films were varied depending on their blending ratio. In the packaging application for potatoes and green onion, the blend films exhibited preventing of greening of packaged potatoes and also showed antifogging effect with reduced quality changes in the packaging of green onion. The blend films have high potential for being used as UV screening or antifogging packaging films.