Abstract: High density polyethylene was grafted with maleic anhydride (leading to PE-HD-g-MAH), which was introduced into blends of ultra high molecular weight polyethylene (PE-UHMW) and polyamide 66 (PA66) to improve its mechanical and tribological behavior. The micro-structure, wear and friction transfer film surface of the blends were analyzed using SEM, the viscoelastic behavior of the blend were tested using the DMA and capillary rheometer, the chemical characteristic peaks of the blends were analyzed using FT-IR before and after friction. It showed that PE-HD-g-MAH improved the compatibility between PA66 and PE-UHMW and the tensile, bending, and impact strengths were improved. With increasing PE-HD-g-MAH, friction coefficient of the blends decreases gradually. No chemical reaction occurred during the frictional process. PE-HD-g-MAH also improved the temperature resistance of the blend. The fatigued wear was shown on the worn surface. The addition of PE-HD-g-MAH inhibits the growth of fatigue crack, so that the homogeneous transfer film became uniform gradually.

Key words: polyamide 66, ultra high molecular weight polyethylene, high density polyethylene grafted maleic anhydride, mechanical property, tribology