CONDUCTIVITY AND DIELECTRIC BEHAVIOR OF PLiAMPS-BASED SEMI-IPN SINGLE ION CONDUCTOR PLASTICIZED WITH POLY (SILOXANE-G-ETHYLENE OXIDE)

Comb poly(siloxane-g-ethylene oxide) (PSi-PE) with high chain segmental mobility, as a plasticizer, was introduced into poly(lithium 2-acrylamido-2-methyl-1-propanesulfonate) (PLiAMPS)based semi-interpenetrating polymer network single-ion conductors. The structures of PSi-PE and PLiAMPS were characterized by FTIR spectroscopy. The distribution of PSi-PE in polyelectrolyte matrix was investigated through observing the residual surface morphology of conductor membrane after being etched by toluene. AC impedance and dielectric behavior measurements were used to investigate the impact of PSi-PE on the ionic conductivity and to analyze the mechanism of conductivity variation. Compared with the unplasticized membranes, the ionic conductivity of the membrane with the addition of 35wt.% PSi-PE was improved by 20 times. Meanwhile, the dielectric constant (epsilon) of the membrane was increased to 1330 and the relaxation time was decreased to 0.012 s. The changes of dielectric properties reflect directly the effect of PSi-PE on the dissociation ability of Li+ and the chain segmental mobility, which well explains the reasons of ionic conductivity variation.