Electron spin resonance studies of the effect of γ-radiation and of hydrogen atoms upon various olefinic carboxylic acids and their amides

Abstract

Olefinic carboxylic acids and amides have been studied at 77 K and room temperature after exposure to H atoms and γ-rays. At 77 K certain radicals (e.g., Me₂Ċ·CO₂H, from α-methylacrylic acid and Me₂Ċ·CH₂·CO₂H from ββ-dimethylacrylic acid) were observed, some of which were converted into polymer radicals on annealing to room temperature [e.g., RCH₂·ĊMe(CO₂H) from α-methylacrylic acid]. Several differences between H atom and γ-ray bombardment were noticed, especially the tendency of H atoms to add to olefinic bonds in cases where γ-rays gave allylic radicals. Results are discussed in terms of reaction mechanisms.