Magnetic resonance studies on cross-links in polyethylene and its model compound

Difference in mobility was detected between the γ-irradiated and neutron irradiated eicosane by analysis of ESR spectra obtained by the spin-trapping method. Three kinds of cross-linked dimers were found by FI mass spectroscopy; saturated cross-linked dimer, cross-linked dimers having either one double bond or two. The relative intensities of these dimers were also different between the γ and neutron irradiated ones. 13C-NMR spectra were observed from the cross-linked n-eicosane. CH2 peaks in the NMR spectrum were clearly distinguished from others by the INEPT method. The analysis of the NMR spectra indicated that the majority of the cross-links formed were the H-type. 13C-NMR of irradiated PE obtained by the CP-MAS method was also discussed. (author)