Improving the integration of HDPE/UHMWPE blends by high temperature melting and subsequent shear

• HDPE/UHMWPE blends were treated by high temperature melting and subsequent shear.
• High temperature melting improved the chain diffusion across the phase interface.
• The UHMWPE phase could be partially swelled by HDPE.
• UHMWPE was better mixed with HDPE as the form of smaller particle or molecular chain by subsequent shear.

Blends of high density polyethylene (HDPE) and ultra-high molecular weight polyethylene (UHMWPE) were prepared by melt blending, and then the high temperature melting (HTM) and subsequent shear were used to improve the integration of HDPE with UHMWPE. Based on accelerating diffusion of polymer chains at high temperature, our hypothesis was that the HTM could enhance chains diffusion across the phase interface, thus the integration of HDPE with UHMWPE components could be improved. An important finding of this study was that melting HDPE/UHMWPE blends at 280 °C in inert atmosphere improved the swelling of UHMWPE by HDPE and enhanced the phase interaction. And then a subsequent shear resulted in a better integration of HDPE with UHMWPE components than that by a conventional process.