Article ID Journal Published Year Pages File Type
5150289 Solid State Ionics 2017 8 Pages PDF
Abstract
Herein, thermophysical and electrical properties of different polymer membranes, prepared by incorporating different amounts of room temperature ionic liquid (IL), N,N-diethyl-N-(2-methacryloylethyl)-N-methylammonium bis(trifluoromethylsulfonyl) imide ([DEMM][TFSI]), in poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) polymer, have been studied. The study reveals that [DEMM][TFSI] IL essentially reduces the crystal growth and promotes electroactive β-phase transformation within the polymer matrix by the interaction between the polymer chains and IL cations. The ionic conductivity of polymeric membranes increases with increasing IL content and attains a maximum value of 4.0 × 10− 4 S·cm− 1 for highest fraction of ionic liquid (50%) at room temperature (303K). Correlation between ion transport and segmental relaxation in polymer membranes has been analyzed using dielectric spectroscopy. The analysis shows that with increasing faction of the ionic liquid the ionic conductivity gradually decouples from the segmental dynamics of the polymer. This is attributed to the higher diffusivity of relatively free anions at lower temperatures, where the segmental dynamics of polymer significantly slow down.
Related Topics
Physical Sciences and Engineering Chemistry Electrochemistry
Authors
, , , ,