Revealing the Relationship Between the Entanglement Densities and Tribological Performance of UHMWPE

Abstract

Ultra‐high molecular weight polyethylene (UHMWPE) can be used as the candidate material for mixed transmission pipelines due to its fabulous wear durability, corrosion resistance, and self‐lubricating qualities. Nonetheless, the connection between its microstructures and tribological performance is still unclear, and hence it is difficult to elucidate the mechanism of its wear resistance. Four types of UHMWPE samples (GUR 400Fine, GUR 4012, GUR 4130, and GUR 4150) were chosen for this study, and their tribological properties were tested. The results show that the coefficient of friction (COF) and wear rate (WR) of GUR 4130 decrease as the temperature increases, but its crystallinity would not be changed while its entanglement density increases and they were confirmed by dynamic mechanical analysis. Additionally, GUR 400Fine and GUR 4012 have similar molecular weight, GUR 400Fine's COF and WR are 1.12 and 1.37 times higher than those of GUR 4012 due to its lower entanglement density. Additionally, higher molecular weight causes higher entanglement density and better tribological performance. In conclusion, we have prepared UHMWPE with better wear resistance through a simple processing method.