FT-IR studies on interactions among components in hexanoyl chitosan-based polymer electrolytes

Fourier transform infrared (FT-IR) spectroscopic studies have been undertaken to investigate the interactions among components in a system of hexanoyl chitosan-lithium trifluoromethanesulfonate (LiCF3SO3)-diethyl carbonate (DEC)/ethylene carbonate (EC). LiCF3SO3 interacts with the hexanoyl chitosan to form a hexanoyl chitosan-salt complex that results in the shifting of the N(COR)(2), C=O-NHR and OCOR bands to lower wavenumbers. Interactions between EC and DEC with LiCF3SO3 has been noted and discussed. Evidence of interaction between EC and DEC has been obtained experimentally. Studies on polymer-plasticizer spectra suggested that there is no interaction between the polymer host and plasticizers. Competition between plasticizer and polymer on associating with Li+ ions was observed from the spectral data for gel polymer electrolytes. The obtained spectroscopic data has been correlated with the conductivity performance of hexanoyl chitosan-based polymer electrolytes. (c) 2005 Elsevier B.V. All rights reserved.