Evaluation of Dynamic Mechanical and Thermal Behavior of HDPE Reinforced with MWCNT/h-BNNP: An Attempt to Find Possible Substitute for a Metallic Knee in Transfemoral Prosthesis

Abstract

Nanotechnology has extended applications of conventional engineering plastics like high-density polyethylene (HDPE) to different biomedical implants such as articular cartilage and fracture fixation plates. However, applications in a load-bearing element like a prosthetic knee require estimation of static, dynamic mechanical, and variation of mechanical properties with temperature. The current work reports on the application of HDPE-based nanocomposite as a possible substitute for a metallic knee in a prosthetic leg. HDPE was reinforced with multiwalled carbon nanotubes (MWCNTs)-1D and boron nitride nanoplatelets (h-BNNPs)-2D to form different composites and hybrids. The preparation route followed the mechanical mixing tandem by curing in a vacuum oven. Dynamic mechanical thermal analysis (DMTA) results confirmed the best elastic and damping property by 0.1 MWCNT composite. The mechanical properties like hardness, impact toughness, and stiffness of 0.25 MWCNT/0.15 h-BNNP were observed to increase by 172 %, 190 %, and 50 % in comparison with pure HDPE. A similar observation was noted during the evaluation of thermal conductivity, thermal stability, and %crystallinity. A modified Halpin–Tsai and Hamilton–Crosser model was used to predict the stiffness and thermal conductivity of composites. The test results confirmed 0.25 MWCNT/0.15 h-BNNP as a potential possible substitute for a metallic knee in a transfemoral prosthesis.