Effect of γ irradiation and Vitamin-E on the thermal and mechanical properties of graphene/nanodiamond reinforced hybrid UHMWPE nanocomposites

Abstract

This work focus on solving the problems of fabricating inadequate prosthetic joint from mechanical perspective in total joint replacement. Ultra high molecular weight polyethylene (UHMWPE) composites with different weight fractions of Graphene (Gr) and Nanodiamond (ND) nanoparticles (0.2–0.5 wt %) were prepared by high pressure compression molding. The effect of vitamin E (vit E) and gamma irradiation at 50 kGy and 100 kGy doses on the structural and thermal properties of UHMWPE composites were investigated through swell ratio test, fourier transformation infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The mechanical properties including tensile, flexural, impact test, nanoindentation and micro scratch were studied and the fractured surfaces were analyzed under scanning electron microscope (SEM). Influence of gamma irradiation on UHMWPE composites shows better crosslinks and crystallinity in the polymer matrix. The nano-composites shows significant improvements in various mechanical properties compared to the 0.5 wt % vitamin-E + UHMWPE composite, with a 23 % increase in Young's modulus, a 21 % increase in flexural strength, a 24 % increase in hardness, and a 17 % increase in impact strength. The results shows that 100 kGy gamma irradiated composites exhibited better results. Composite with 0.5 wt % vit E + 0.3 wt % Gr + 0.5 wt % ND shown significant improvement in structural, thermal and mechanical properties.