Radiolysis of polyethylacrylate and poly-ß-chloroethylacrylate-I

Radiation induced crosslink formation, main chain scission and product formation for polyethyl acrylate (PEA), poly-ß-chloroethyl acrylate (PCIEA) and copolymers of the two components were investigated. Partially deuterated polymers were used to identify the positions of reaction. Radiolysis of PEA induces degradation of the ethyl ester group. The primary step is either hydrogen abstraction from the α-position of the ethyl group or removal of larger fragments (ethyl, ethoxy, methyl radicals) giving rise to the formation of the following volatile products: H₂ (G=0·46), CO (G=0·7), CO₂ (G=0·12), C₂H₆ (G=0·22), C₂H₄ (G=0·07), CH₄ (G=0·08), CH₃CHO (G=0·15), C₂H₅OH (G=0·18). The results obtained for partially deutrated polymers show that degradation of the ethyl ester group precedes crosslinking (G_ci=0·32) as well as main chain scission (G_sc=0·14). The G-value for crosslinking increases with increasing content of ß-chloro-ethyl acrylate in the copolymer. G_ct for pure PCIEA is found to be 2·2.