Tribological properties of organotin compound modified UHMWPE

A range of ultra-high molecular weight polyethylene (UHMWPE)/tetraphenyltin (Ph 4 Sn) nanocomposites were fabricated by hot-pressing. The surface hardness and crystallinity of composites were studied. It revealed that the surface hardness of the composites decreased slightly, and the changing trend of crystallinity was consistent with the hardness. The tribological properties of composites under seawater lubricating conditions were investigated. The experimental results showed that the friction coefficients of the composites almost keep the same but the wear reduced sharply. With the increases of Ph 4 Sn content, the wear of composites first decreases significantly and then increases, meanwhile the friction coefficient remains basically unchanged. The dominant wear mechanism has changed from adhesive wear to plastic deformation and finally to abrasive wear. The addition of Ph 4 Sn particles reduces the sensitivity of the Ph 4 Sn/UHMWPE composites to water and transfers the load to the UHMWPE network, resulting in the wear resistance improved.