Pyrolysis, UV light, and electron beam induced degradations of poly[bis(trifluoroethoxy) phosphazene] have been studied with ESCA and infrared and mass spectroscopic techniques together with gas chromatographic separation. The data obtained reveal the structural changes taking place in the polymer backbone due to the cross-linkage and the oxygen shift to the nitrogen upon the side group elimination. These studies support the mass spectroscopic data of the gaseous products formed in the side group removal. © 1979, American Chemical Society. All rights reserved.