Enhanced thermal performance and impact strength of UHMWPE/Recycled-PA6 blends synthesized via a melting extrusion route

The blends of ultra-high molecular weight polyethylene (UHMWPE) and recycled-polyamide 6 (R-PA6) were prepared via a melting extrusion route using high-density polyethylene-graft-maleic anhydride (HDPE-g-MAH) as the compatibilizer. The morphologies and distributions of the chemical components of the blends were characterized by scanning electron microscopy and synchrotron Fourier transform infrared microspectroscopy. The effects of R-PA6 content on the Vicat softening temperature (VST), heat distortion temperature (HDT), and impact strength of the blends were studied. Remarkably, in comparison with those of UHMWPE, the VST and HDT of UHMWPE/R-PA6 blends with 44 wt% R-PA6 were increased to 165.1 and 98.4°C, respectively, and the Charpy impact strength and Izod impact strength of the blends were enhanced to 33.9 and 16.2 kJ/m², respectively. In addition, it was found that the blending system containing 44 wt% R-PA6 and 48 wt% UHMWPE exhibited the best compatibility when it was prepared using 8 wt% HDPE-g-MAH. The distribution of the phases of UHMWPE and R-PA6 was uniform, and no obvious phase separation was observed in the blends.