Rheological Behavior of High-melt-strength Polypropylene with Long-chain-branching Structure-Shear Rheology

High-melt-strength polypropylene with long chain branching (LCB-HMSPP) was prepared via irradiation. The rheological behavior of LCB-HMSPP was investigated using an advanced rheometric expansion system (ARES) and a capillary rheometer. The dynamic rheological test indicated that the melt elasticity increased with increasing sentilizer content, reflected as increase in G′, zero-shear-viscosity, and reflaxation time, and decrease in tanδ. Introducing a small amount of PE-UHMW also enhanced the elasticity. The capillary rheological test revealed that LCB-HMSPP exhibited higher flow activation energy and temperature sensitivity compared with PP devoid of irradiation.