Towards identifying the new structures formed on the γ-radiolysis of Ultem

Ultem irradiated up to 10.0 MGy has been analysed using 13C, 1H and 2D proton-carbon and proton-proton correlation NMR spectroscopy to shed light on the formation of new structures. Chemical shifts and correlation data were used to determine the structure or partial structures of several new components. The spectra indicated the presence of new groups and structures involving the isopropylidene group, the imide ring, and hydrogen-abstraction reactions. Possible pathways for formation of the new structures are proposed and the G-values for their formation have been estimated