Radiation effects in polyethylene and n-alkanes

The effect of high-energy radiation on n-alkanes and polyethylene (PE) are reviewed. The article includes a description of (a) primary radiation events, formation, spatial distribution and decay of free radicals and radical migration mechanisms, (b) formation of cross-links and other stable products, (c) the effects of crystallinity, crystalline modifications and morphology on radiation cross-linking, and (d) radiation-induced changes in the crystal lattice and the destruction of crystallinity at high irradiation doses. An attempt is made to bring together conflicting views on various unsolved problems of the radiation physics and chemistry of these important and much studied substances. Long-chain paraffins are given considerable attention since their radiation behaviour often provides a link between that of PE and its short-chain analogues.