Kinetic of poly(vinylidene fluoride) defluorination under X-ray irradiation

Modification of the photoelectron and C KVV spectra during the long-term surface degradation of partially crystalline PVDF under simultaneous soft X-ray and electron irradiation are reported. Deep radiative carbonization brings about the formation of carbynoid structures (chain-like carbon) in the surface; as a result the shape of the electron emission spectra of carbon in the carbonized sample essentially differs from that of graphite and PVDF. Analysis of carbon core-level electron spectra via decomposition onto spectral components shows presence of partially (CH, CF) and fully (=C=, -C≡) carbonized units of polymeric chain thus pointing on two-step mechanism of polyme ric chain transformation from the initial to a carbynoid. Results of the mathematical modeling of the first step of the chain transformation show it to be a second order process.