The physical and chemical properties of gamma ray irradiated polymer electrolyte films

Modified Thermal, Dielectric, and Electrical Conductivity of PVDF-HFP/LiClO4Polymer Electrolyte Films by 8 MeV Electron Beam Irradiation

“…The initial decomposition temperature of the thermogram for the irradiated films reveals a gradual decrease in melting temperatures ( T m ) and a shift toward the lower end with dose, confirming the change in molecular structure as well as decreased weight of polymer electrolyte is a result of the creation of free radical via oxidative degradation process leading to increase in the amorphousity and decrease in crystalline region at high EB dosage. 12,29 Hence, these results confirm the influence of irradiation and are well agreed with the obtained XRD results.…”

“…The third major loss in 330–565 °C (residual decomposition) was attributed to the destruction of polymeric chain backbone by decrease in degradation temperatures to 460, 456, 450, and 418 °C in DTA corresponding to unirradiation, 40, 80, and 120 kGy, respectively, clearly indicating that the change in molecular structure of the polymer matrix leads to increase in amorphousity at higher dosage. 12 The remaining residues due to degradation with increasing dose in two temperature ranges 295–330 and 540–565 °C are presented in Figure 5d, corresponding to the decomposition of host polymer chain with increased dose. The initial decomposition temperature of the thermogram for the irradiated films reveals a gradual decrease in melting temperatures ( T m ) and a shift toward the lower end with dose, confirming the change in molecular structure as well as decreased weight of polymer electrolyte is a result of the creation of free radical via oxidative degradation process leading to increase in the amorphousity and decrease in crystalline region at high EB dosage.…”

“…As the irradiation dose increased, the polymer chain scission occurs, which provides more flexibility to ions in the polymer matrix to move easily, in turn, improving the conductivity. 12,45…”

“…11 It is also important to understand the charge transport mechanism in the polymers by studying the electrical conductivity and dielectric relaxation upon EB irradiation. 6,12 Few studies have reported changes in thermal property, structural arrangement, surface morphology, and electrical conductivity upon EB irradiation on copolymers like polypropylene, poly(vinyl chloride), etc. 13,14 In the present case, poly((vinylidene fluoride)- co -hexafluoropropylene) (PVDF-HFP) is one of the copolymer considered as a suitable host due to various interesting properties like high dielectric constant (ε = 8.4) that support dissociation of salts like Na + and Li + , low crystallinity, which can improve conductivity.…”