NUKLEONIKA 2006, 51(Suppl. 1):s121-s128

INFLUENCE OF RADIATION STERILIZATION ON POLY(ESTER URETHANES) DESIGNED FOR MEDICAL APPLICATIONS

Grażyna Przybytniak1, Ewa Kornacka1, Joanna Ryszkowska2, Monika Bil2, Andrzej Rafalski1, Piotr Woźniak3, Małgorzata Lewandowska-Szumieł3

1 Institute of Nuclear Chemistry and Technology, 16 Dorodna Str., 03-195 Warszawa, Poland
2 Faculty of Materials Science and Engineering, Warsaw University of Technology, 141 Wołoska Str., 02-507 Warszawa, Poland
3 Department of Biophysic and Human Physiology, Medical University of Warsaw, 5 Chałubińskiego Str., 01-004 Warszawa, Poland

Preparation of scaffolds for tissue regeneration requires elucidation of chemical and physical processes induced by ionizing radiation during radiation sterilization of polymeric materials used for these purposes. Such treatment induces many unintended and desired reactions that lead either to degradation or cross-linking of macromolecules. It was found that in poly(ester urethane) the ester segments are responsible predominantly for radiation induced phenomena. Some radicals generated following irradiation were identified under cryogenic conditions. Upon exposure to sterilizing dose cross-linking was confirmed on the basis of rheological changes in melted polymers. The results obtained by EPR spectroscopy and DRS revealed a relatively high susceptibility of poly(ester urethanes) on oxidation.