Isothermal crystallization behaviors and kinetics of nucleated polylactide/poly(butylene adipate-co-terephthalate) blend films with talc

摘要

Polylactide (PLA) and its blend films with and without a compatibilizer in the presence of poly(butylene adipate-co-terephthalate) (PBAT) and talc were prepared through a twin-screw extruder. The effects of PBAT, talc, and various contents of compatibilizer on thermal and morphological properties as well as crystallization of these blends were investigated. PBAT and talc were used as a flexible polymer and a nucleating agent at 10 mass% and 1 phr, respectively, whereas methylenediphenyl diisocyanate was used as a compatibilizer at different amounts (1-7 mass% based on PBAT contents). Isothermal crystallization behaviors and kinetics of neat and nucleated PLA blends were evaluated by differential scanning calorimeter and polarized optical microscope. The Avrami and Arrhenius equations were used to investigate the crystallization kinetics. The results revealed that the presence of PBAT and talc in the films led to an increment of crystallization rate of PLA via a synergistic effect under isothermal crystallization conditions. However, the crystallization rate significantly decreased with increasing the crystallization temperature (T-c). These results were in agreement with crystallization kinetic and morphological studies, suggesting that the crystallization behaviors, kinetics, and mechanisms of PLA were affected by these factors.