γ-Radiolysis of ketone polymers. I. Studies of symmetrical aliphatic ketones as model compounds

γ-Radiolysis of model ketones of the general structure R(C?O)R, neat and in hydrocarbon solution, show that the radio-chemical degradation of these aliphatic ketones can be explained by mechanisms analogous to those generally accepted for the photochemical decompositions of the same compounds. The G (type I) and G (type II) yields are found to decrease with increasing total chain length of the ketone as monitored by the products (R? H) and (CH₃CO? R), respectively. Differences in the relative yields of type I and II products are attributed to the higher incident energies involved in γ-radiolysis as compared to ultraviolet photolysis. Evidence is presented for energy transfer from paraffinic solvents to aliphatic ketonic solutes. Solid- and condensed-phase studies show the importance of rotational and diffusional mobility to the yields of the type II and I processes, respectively.