Abstract: A simple method was used to promote the diffusion of highlyentangled molecular chains of ultra high molecular weight polyethylene (PE-UHMW) and ethylene propylene rubber(EPR) leading to blends of EPR/PE-UHMW, which was further mixed with polypropylene (PP) forming PP/EPR/PE-UHMW ternary blends. The blends were characterized by rheological measurement and differential scanning calorimeter (DSC). The rheological tests displayed a long relaxation mechanism occurring in the lowfrequencies region. The interentanglement structure restricted the diffusion of EPR into PP matrix. DSC showed that the plasticization of PE-UHMW resulted in decreasing in crystallization temperature and increasing indegree of crystallinity. The addition of EPR/PE-UHMW blend to PP matrix caused a multiple melting behavior of PP.

Key words: polypropylene, ethylene propylene rubber, polyenthylene, high-temperature melting