Abstract: In this work, crosslinked polyethylene (PE) was first prepared by a silane-crosslinking method, and then was melt-blended with the recycled PE obtained from the water-separated waste PE films. There was a change in aggregation structure observed from the fracture surfaces of blending samples by scanning electronic microscopy, Which indicates the formation of decentralized isomeric structure due to the incorporation of crosslinked PE into the recycled one. The effects of crosslinked PE content on mechanical and rheological properties were evaluated, and differential scanning calorimetry and X-ray diffraction were conducted to investigate the crystallinity and crosslinking degree of the blending sample containing 15 wt% of crosslinked PE. The results indicated that the tensile strength and impact toughness of the recycled PE were improved significantly due to the decentralized isomeric structure, whereas the elongation at break and melt flow rate showed a decline to some extent. The blend sample containing 15 wt% of the crosslinked PE was found to achieve an optimum performance and also exhibit the best crystallinity at a crosslinking degree of 33.5 %.

Key words: recycled polyethylene, silane-crosslinking method, isomeric structure, modification