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

TL;DR

This study investigates how high doses of electron beam irradiation affect the chemical structure and mechanical properties of medical grade polyurethane, revealing inhomogeneous degradation and molecular changes.

Contribution

It provides detailed analysis of molecular and structural changes in TPU caused by electron beam irradiation, highlighting effects at high doses.

Findings

Decreased molecular mass after irradiation

Increased polydispersity indicating inhomogeneous degradation

Altered mechanical properties due to structural changes

Abstract

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