Processing and charecterizaion of UHMWPE/alpha-tocopherol-CNTs nanocomposites

?-Tocopherol is the component of Vitamin E with the highest antioxidant activity, as it is able to react with free radicals in the cell membranes and protect polyunsaturated fatty acids from oxidative degradation. Its antioxidant activity is due to the extraction of hydrogen from the-OH group present on the aromatic ring, by means of a free radical peroxidic. This process leads to the formation of a radical ?-tocopheroxilic, that can combine with another free radical peroxidic. ?-Tocopherol can prevent that two peroxy free radicals attack other chains of fatty acids to produce other free radicals; in this way the oxidative cascade is blocked. In recent years, this molecule has been widely used to increase the biostability and biocompatibility of many polymeric materials. In this work, the stabilizing effect of ?-tocopherol physically immobilized onto the MWCNTs surface, against oxidative degradation of UHMWPE has been studied. The ?-tocopherol was physically immobilized, following two different paths, onto the outer surface of MWCNTs previously functionalized, and the so obtained hybrid-nanoparticles were processed with UHMWPE by hot-compaction.