The compatibilization of poly (propylene carbonate)/poly (lactic acid) blends in presence of core-shell starch nanoparticles.

A novel core-shell starch-based nanoparticles (CSS NPs) with a "hard" starch core and a "soft" poly (methyl acrylate) (PMA) shell was prepared and incorporated into a PPC/PLA blend. The excellent compatibilization of CSS NPs was revealed by atomic force microscope (AFM), differential scanning calorimetry (DSC) and rheological test. More importantly, due to the excellent compatibilization the resulted PPC/PLA/CSS blend exhibited a strikingly improved mechanical and thermal properties. Compared to PPC/PLA (60/40), the elongation at break of PPC/PLA/CSS (60/40/20) increased greatly from 15 % to 272 % without sacrificing the tensile strength. Besides, the heat distortion temperature (HDT) of PPC/PLA/CSS (60/40/20) was improved to 47.3 °C, which was 20.5 °C higher than that of the neat PPC. These results established a novel and efficient strategy to improve the compatibility of polymer blends and to prepare polymer blends with balanced toughness and stiffness.