Biodegradable Poly(Butylene Adipate‐Co‐Terephthalate)/Poly(Propylene Carbonate)/Talc Composite Films With Enhanced Oxygen and Water Barrier Properties

ABSTRACT As fossil resources become increasingly depleted, replacing petroleum‐based non‐degradable plastics with biodegradable alternatives has become an inevitable trend in modern societal development. Poly(butylene adipate‐co‐terephthalate) (PBAT), renowned for its excellent ductility and biodegradability, has been widely utilized in packaging and agricultural mulching applications. However, the high cost and poor barrier properties of PBAT limit its application. In this study, a low‐cost and high‐barrier talc‐filled PBAT/poly(propylene carbonate) (PPC) blend composite film was prepared by blending PPC and layered talc with PBAT followed by further interfacial modification. The results revealed that incorporating 1 wt.% of ethylene‐methyl acrylate‐glycidyl methacrylate (EGMA) significantly enhanced the compatibility of PBAT and PPC. Compared to the unmodified blends, the barrier properties against water vapor and oxygen for the compatibilized blend films showed improvements of 8% and 41%, respectively. After further adding 20 wt.% talc and modifying with coupling agents, the dispersibility of talc powder in the blend matrix and its compatibility at the interface between components were improved. Thus, their water vapor and oxygen barrier properties increased by up to 42% and 29%, respectively. This research presents a viable approach to address the cost and performance limitations of PBAT films, thus broadening their application in packaging and agricultural films.