The influence of electron beam irradiation on the chemical and structural properties of medical grade Polyurethane

摘要

Thermo plastic polyurethane (TPU) provides excellent bio-compatibility,flexibility and good irradiation resistance; however, extremely highirradiation doses can alter the structure and function of macromolecules,resulting in oxidation, chain scission and cross-linking. In this study, theeffects of e-beam irradiation on the medical grade thermo plastic polyurethanewere studied. The changes in the chain length and their distribution as well asthe changes in molecular structure were studied. The GPC (Gel PermeationChromatography) results show that the oxidative decomposition is followed by adecrease in molecular mass together with an increase in polydispersity. Thisindicates a very inhomogeneous degradation, which is a consequence of thespecific course and of the intensity of oxidative degradation. This wasconfirmed by means of mechanical property measurements. Overall, this studydemonstrated that the medical grade TPU was affected by radiation exposure,particularly at high irradiation doses.