Reinforcing and Toughening Modification of PPC/PBS blends with Epoxy Terminated Hyperbranched Polymers as Compatibilizer

Polypropylene carbonate (PPC)/polybutylene succinate (PBS) blends were prepared by melt-blending with terminal epoxy-based hyperbranched polymers (EHBP) as modifier. The thermal properties, mechanical properties, rheological properties and fracture morphology were characterized by dynamic thermomechanical analyzer (DMA), thermogravimetric analyzer (TGA), electronic universal testing machine, rotating rheometer and scanning electron microscope (SEM), etc. Upon addition of EHBP, the difference between the glass transition temperature of PPC and PBS became smaller, indicating the compatibility of PPC and PBS were improved by EHBP. Furthermore, by adding 0.5phr of EHBP, the impact strength increased from 9.55 kJ/m− 2 to 17.31 kJ/m− 2, the elongation at break increased from 136.29–204.39%, and the tensile strength increased from 10.00 MPa to 16.84 MPa. The fracture surface of the PPC/PBS blends became rough with the increase of EHBP, even with large filamentous structures and tiny holes, which further demonstrated that EHBP acted as an excellent toughening effect on PPC/PBS. Gel content analysis confirmed that both physical and chemical micro-crosslinking were formed after incorporation of EHBP.