Role of Stably Entangled Chain Network Density in Shish-Kebab Formation in Polyethylene under an Intense Flow Field

Abstract

The physically entangled chain networks, formed by a long-chain polymer component, have been demonstrated to be very effective for shish-kebab formation in a flow field. However, an open question still remains whether there is an optimal content of entangled chain networks. The answer is crucial in the academic and industrial fields but faces a challenge since physically entangled chain networks are not stable, which tend to disentangle during flow. In the current work, we utilized lightly cross-linked chain networks, which can be considered as stably entangled chain networks (SECN), to study the role of SECN density in shish-kebab formation under an intense flow field. The SECN density was adjusted by adding various contents of lightly cross-linked polyethylene (PEX) in short-chain polyethylene, and the intense flow field was applied by a modified injection molding machine, so-called oscillation shear injection molding (OSIM). The results show that the structure in the core layer of the OSIM samples coul...