writer：Ruoyun Li, Linbo Wu*, Bo-Geng Li.
keywords：Poly(L-lactide), Plasticization, Toughening, Multiblock copolymers, Mechanical properties
source：期刊
specific source：Euro Polym J, 2018, 100, 178-186
Issue time：2018年

PEG-mb-PBAT (EB, for simplicity) multiblock copolymers were synthesized via chain extension/coupling of poly (ethylene glycol) (PEG) and poly(butylene adipate-co-terephthalate) (PBAT) diols, and used as modifiers to prepare blends of commercial poly(L-lactide) (PLLA) and EB via melt blending. The EB copolymers were characterized by 1H NMR and DSC, and the PLLA70/EB30 blends were characterized by DSC, SEM, tensile and impact testing. The PEG segments in EB show greatly depressed crystallization as compared with PEG prepolymer,

therefore, exhibit excellent plasticization effect on PLLA. Furthermore, they also compatibilize the PBAT microphase with PLLA matrix. Owing to strong interfacial adhesion, the PBAT micro-phases induces highly oriented shear yielding during impact process and therefore act as efficient tougheners of PLLA. Therefore, the blends possess highly improved toughness (impact strength 44 kJ/m2) and excellent ductility (elongation 160%), and at the same time, retain sufficient stiffness. Furthermore, the L/EB blends show superior mechanical performances than the L/EP (PLLA/PEG-mb-PPA) blends reported by us previously.