Preparation and characterization of poly(butylene succinate-co-adipate)/poly(lactic acid) blends with enhanced compatibility, mechanical properties, and heat resistance

In this study, an environmental friendly poly(butylene succinate-co-adipate) (PBSA)/ poly(lactic acid) (PLA) blend was prepared with 1,4-bis(tert-butyl peroxy isopropyl) benzene (BIPB) as a reactive compatibilizer. Rheological analysis and gel permeation chromatography analysis showed that the addition of BIPB increased the melt strength and molecular weight of PBSA/PLA blends by reacting with PBSA and PLA during the melt-blending process. The morphology of the cryo-fractured surfaces of PBSA/PLA/BIPB blends showed that adding BIPB could significantly enhance the compatibility between PBSA and PLA. Moreover, the tensile tests showed that adding BIPB could improve the tensile strength, Young's modulus and breaking strain of PBSA/PLA blends. Furthermore, the effect of isothermal treatment on PBSA/PLA/BIPB blends was also studied. Wide angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC) curves showed that the isothermal treatment could obviously increase the crystallinity of PLA and then increase the heat deflection temperatures of PBSA/PLA/BIPB blends. In addition, adding PLA could significantly improve the hydrolytic properties of PBSA/PLA/BIPB blends.