High gamma dose response of poly(vinylidene fluoride) copolymers

Electron and gamma irradiation‐induced effects in poly(ethylene‐co‐tetrafluoroethylene) films

“…Over the entire band, the typical absorbance of hydroxyl (OH) in the broad band of 2400-3800 cm À1 is not found (Figure 1c,d). This is different from the previous observations for the irradiated ETFE, 29,56 poly(vinylidene fluoride-trifluorethylene) [P(VDF-TrFE)], 57,58 poly(vinylidene difluoride-co-hexafluoropropylene) [P(VDF-HFP)], 59 PTFE, 60 and PFA films. 61 In these irradiated polymers, the hydroxyl characteristic band was found even in the low-dose range either in air or in vacuum conditions.…”

“…The signatures at 1715 (peak I) and 1746 cm À1 (peak III) are assigned to the C C stretching vibrations of in-chain and terminal double bonds. 57,59,64,65 However, that a characteristic wavenumber of peak III (1746 cm À1 ) is higher than those of peak I (1715 cm À1 ) is due to the higher electronegativity of two F atoms in a CH CF 2 group (peak III) comparing to that of a CH CF group (peak I). At the same time, the presence of oxidation bonds possibly including ketone ( CO ) and acid fluoride ( COF) was previously identified at higher frequencies of 1730-1850 cm À1 .…”

“…Table 1 presents some other fluoropolymers that have been examined for application in radiation dosimeters. 57,59,[73][74][75][76] These fluoropolymers were tested mostly with gamma rays from 60 Co sources using FTIR, UV-Vis, electron paramagnetic resonance (EPR), electron spin resonance (ESR), and differential scanning calorimetry (DSC) measurements. The irradiated dose range was investigated from 0 to 2300 kGy.…”

“…The observed features are attributed to at least three components of C C conjugated bonds, which appear as alkenes ( C C ), dienes ( C C C C ), and trienes ( C C C C C C ). 31,57,82 The recombination of carbon-centered radicals either in-chain or chain-end species can lead to the further development of unsaturated carbon bonds in the irradiated ETFE films. 28 In such a way, the presence of new double bonds results in the reduction of binding energy of the outer atoms, providing active sites for the formation of other conjugated C C bonds.…”

Optical properties and ionic conductivity studies of an 8 MeV electron beam irradiated poly(vinylidene fluoride-co-hexafluoropropylene)/LiClO4electrolyte film for opto-electronic applications

“…bond due to hydrophobic processes (H-bond breaking) with a high dose, conrming the degradation of the polymer. 36 The presence of double bonds along the polymer chain can decrease the binding energy of the polymer and produce radiation induced conjugated C]C bonds continuously and as a result, single bonds (194 nm) disappear to produce double (223 nm) and triple (274 nm) bonds 34,37 which may be attributed to polymer chain scissioning 38 resulting from a decrease in the band gap energy aer irradiation.…”