Superior ductile poly(glycolic acid)/poly(butylene adipate-co-terephthalate) blends compatibilized by triphenyl phosphite

Abstract

Present study was aimed at exploring the compatibilization of poly(glycolic acid)/ poly(butylene adipate-co-terephthalate) (PGA/PBAT) blend in the presence of triphenyl phosphite (TPP) to prepare the ductile blend. The chain extension was monitored by the change torque value, which consisted with rheological behavior, that is, the increased TPP content led to an enhancement of melt strength for PGA/PBAT. TPP acted as a bridge to generate PGA-g-PBAT copolymer, promoting the interfacial interaction and miscibility of polymers. After being reactively compatibilized by 3 wt% TPP, the elongation at break, notched impact strength, and fracture toughness of the modified blend were increased by 627%, 60%, and 583% respectively. The morphology of impact-fractured surface revealed that the size of PBAT particles decreased from 2.05 µm to 1.35 µm with 3 wt% of TPP. The compatibilized blend with ductile feature was attributed to the interfacial debonding appending the fibrillation. Furthermore, when the content of TPP reached 5 wt%, the promoted chain entanglement led to a reduction of ductility. This work provided a facile strategy for the preparation of ductile PGA/PBAT blend.