Media type: E-Article Title: HYSCORE and Davies ENDOR study of irradiated ultra high molecular weight polyethylene Contributor: Paganini, Maria Cristina; Brunella, Valentina; Chiesa, Mario Published: Wiley, 2012 Published in: Magnetic Resonance in Chemistry, 50 (2012) 9, Seite 615-619 Language: English DOI: 10.1002/mrc.3849 ISSN: 0749-1581; 1097-458X Keywords: General Materials Science ; General Chemistry Origination: Footnote: Description: Ultra high molecular weight polyethylene (UHMWPE) has been studied with different magnetic resonance techniques to elicit information on the nature and the location of radicals generated during high energy irradiation. Field swept electron paramagnetic resonance, pulsed Davies electron nuclear double resonance and hyperfine sublevel correlation spectroscopic measurements allowed extracting for the first time the full 1H hyperfine coupling tensors of the most abundant radical, i.e. a secondary alkyl radical and to ascertain the formation of allyl radicals in the first stages of the irradiation process. The 1H hyperfine coupling tensors are analogous to those reported for single crystal irradiated polyethylene, suggesting that radicals generated in UHMWPE are located in the crystalline region of the polymer. Copyright © 2012 John Wiley & Sons, Ltd.