The investigation on the radiation chemistry of the perfluoropolyethers carried on through the analysis of the free radicals intermediates, of the structural changes in the oligomers chains and with the support of M.O. calculations has afforded information on the major features of the mechanism of radiolysis. The main radiolytic process is chain degradation by CC and CO bond rupture. Evidence of a minor participation of CF bond scissions have been obtained in the case of poly(perfluorotrimethylene oxide) PF3MO and poly(perfluoroethylene-perfluoromethylene oxide) PFEMO. The nature of the radicals intermediates and the structure of the novel units produced in the oligomer chains fit a radiolysis mechanism where both the ionic and excitation paths seem to be operative giving rise to complex sequence of radical reactions. The structure and possible reaction modes of the molecular cation and anion radicals are discussed on the basis of PM3 semi-empirical M.O. calculations.
The radiation chemistry of perfluorinated ethers
FAUCITANO, ANTONIO;BUTTAFAVA, ARMANDO;
1995-01-01
Abstract
The investigation on the radiation chemistry of the perfluoropolyethers carried on through the analysis of the free radicals intermediates, of the structural changes in the oligomers chains and with the support of M.O. calculations has afforded information on the major features of the mechanism of radiolysis. The main radiolytic process is chain degradation by CC and CO bond rupture. Evidence of a minor participation of CF bond scissions have been obtained in the case of poly(perfluorotrimethylene oxide) PF3MO and poly(perfluoroethylene-perfluoromethylene oxide) PFEMO. The nature of the radicals intermediates and the structure of the novel units produced in the oligomer chains fit a radiolysis mechanism where both the ionic and excitation paths seem to be operative giving rise to complex sequence of radical reactions. The structure and possible reaction modes of the molecular cation and anion radicals are discussed on the basis of PM3 semi-empirical M.O. calculations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
