| abstract |
A method for forming a crosslinked oxidation-resistant toughness-enhanced polymeric material includes the steps of placing a previously irradiated polymer material in a heating device under oxygen-reduced atmosphere at a temperature above the melting point of the polymeric material for a sufficient time to (a) eliminate oxidation in the polymeric material, (b) break existing crosslinks into free radicals, (c) migrate and re-distribute radiation-induced free radicals in an uniform manner, (d) create new free radicals by thermal energy and form uniform crosslinks within the polymer micro-structure, and followed by a cooling step to eliminate residual free radicals and form additional uniform crosslinks within the polymer micro-structure. A method of making a crosslinked oxidation-resistant toughness-enhanced wear-reduced UHMWPE medical implant from a previously irradiated solid form of UHMWPE is also disclosed. |