Incorporation of molybdenum disulfide into polyetheretherketone creating biocomposites with improved mechanical, tribological performances and cytocompatibility for artificial joints applications

To improve mechanical, tribological and biological performances of polyetheretherketone (PEEK) for artificial joints applications, molybdenum disulfide (MoS2, MS) nanosheets were incorporated into PEEK to fabricate MS/ PEEK biocomposites (MPC) with MS content of 4w% (MPC4) and 8w% (MPC8). The results revealed that the MS nanosheets with the size of about 400 nm and sheet thickness of about 70 nm were distributed into PEEK matrix, and surface roughness as well as hydrophilicity of MPC increased with the MS content increasing. Moreover, the compressive strength and shore hardness of the MPC were accordingly enhanced. Furthermore, the coefficient of friction of the MPC decreased while the wear resistance of the MPC increased with the MS content increasing in both water-sliding and dry-sliding contact. In addition, rat bone marrow derived stromal cells adhered and proliferated on the composites, indicating that the MPC had no adverse influences on cell behaviors, indicating good cytocompatibility. The results demonstrated that incorporation of MS nanosheets into PEEK produced biocomposites with improved mechanical, tribological and biological performances. MPC8 with no cytotoxicity would have a great potential for artificial joints applications.