Rheological, thermal and mechanical properties of biodegradable poly(propylene carbonate)/polylactide/Poly(1,2-propylene glycol adipate) blown films

Poly(propylene carbonate) (PPC) was blended with polylactide (PLA) and poly(1,2-propylene glycol adipate) (PPA) using a twin screw extruder. Then the PPC/PLA/PPA films were prepared using the blown film technique. DMA results showed that PPA could act as a plasticizer and improve the miscibility between PPC and PLA. Crystal morphology displayed that blending PLA with the amorphous PPC led to a decrease of the spherulite size of PLA. The results of mechanical tests indicated that PPC-rich films showed high elongation at break and PLA-rich films showed high tear strength and good optical properties. The content of PPC and PLA significantly affected the physical properties of the films. With increasing PPC content, the melt strengths of the PPC/PLA/PPA films were enhanced. These findings contributed to the biodegradable materials application for designing and manufacturing polymer packaging.