The assessment of thermal and radiation stability of UHMWPE

Preirradiated ultrahigh molecular weight polyethylene (UHMWPE) was subjected to other cycle of y-exposure in order to explain the behavior of this material after radiation processing. The oxygen uptake investigation was selected for the characterization of thermal stability of multisession irradiation. The long life radicals promote crosslinking or oxidative degradation depending on the second irradiation dose and on the environmental conditions. The main kinetic parameters: oxidation period and oxidation rate were evaluated depicting the availability of radiochemical processing of UHMWPE for further long term applications. Irradiation of UHMWPE in salt solution reveals the improvement in the thermal strength for low exposure doses.