Enhanced compatibility and functionality of thermoplastic cassava starch blended PBAT blown films with erythorbate and nitrite.

Improved miscibility between thermoplastic starch (TPS) and polybutylene adipate-co-terephthalate (PBAT) enhances processability and properties of TPS-based biodegradable plastic packaging. This research investigated compatibility and functionality of TPS/PBAT (50/50) blends with sodium nitrite and sodium erythorbate (1-5%) via blown film extrusion. Film morphology and mechanical and barrier properties were investigated. Sodium nitrite and sodium erythorbate improved processing efficiency of TPS, modified film flexibility and enhanced physical and chemical compatibility between TPS and PBAT matrices via hydrolysis, confirmed by H NMR and ATR-FTIR analyses. These chemical reactions also affected thermal and phase transition behaviors. Increased starch granule dispersion caused smoother microstructure, resulting in higher oxygen barrier. Sodium nitrite and sodium erythorbate functionalized TPS/PBAT films reduced discoloration of packaged cured meat during storage at 4 °C for 9 days. These compounds provided extra functionality and improved compatibility between TPS and PBAT biodegradable plastic blends for novel and sustainable food packaging.