Robust multiphase and multilayer starch/polymer (TPS/PBAT) film with simultaneous oxygen/moisture barrier properties

The demands for bioplastics that provide good barrier properties against moisture and oxygen while simultaneously displaying good physical properties without compromising their biodegradability is ever-increasing. In this work, a multiphase and multilayer film assembly composed of thermoplastic starch (TPS) and its maleated counterpart (MTPS) with poly(butylene adipate-co-terephthalate) (PBAT) was constructed as a suitable barrier film with excellent mechanical properties. The bioplastic film assemblies were fabricated through reactive extrusion, compression molding, and dip-coating process. The incorporation of PBAT co-blend with TPS in the core layer enhanced the multilayer film's interfacial bond. The MTPS/PBAT film assembly provided 86.8% and 74.3% improvement in moisture barrier and oxygen barrier as compared to the baseline TPS and PBAT films, respectively. Overall, the multiphase and multilayer film assembly displayed good mechanical properties in conjuncture with excellent barrier properties indicating their potential as a biodegradable and cost effective alternative to conventional plastics used in the packaging industry.