A biodegradable blend foaming material of poly(butylene adipate-co-terephthalate) (PBAT)/poly(propylene carbonate) (PPC) was successfully prepared by chemical foaming agent and screw extrusion method.First,PBAT was modified by bis(tert-butyl dioxy isopropyl)benzene (BIBP) for chain extension,and then the extended PBAT (E-PBAT) was foamed with PPC using a twin (single) screw extruder.By analyzing the properties of the blends,we found that Young's modulus increased from 58.8 MPa of E-PBAT to 244.7 MPa of E-PBAT/PPC 50/50.The viscosity of the polymer has a critical influence on the formation of cells.Compared with neat PBAT (N-PBAT),the viscosity of E-PBAT increased by 3396 Pa.s and E-PBAT/PPC 50/50 increased by 8836 Pa.s.Meanwhile,the dynamic mechanical analysis (DMA) results showed that the storage modulus(E') at room temperature increased from 538 MPa to 1650 MPa.The various phase morphologies ("sea-island","quasi-co-continuous" and "co-continuous") and crystallinity of the blends affected the spread velocity of gas and further affected the foaming morphology in E-PBAT/PPC foam.Therefore,through the analysis of phase morphology and foaming mechanism,we concluded that the E-PBAT/PPC 70/30 component has both excellent strength and the best foaming performance.