Dielectric properties of chitosan and two ionic derivatives: Effect of counter anions
Abstract
We report herein the dielectric properties response of two ionic chitosan derivatives. More specifically, we report here chitosan derivatives bearing guanidinium groups, prepared through the reaction between chitosan and cyanamide when scandium (III) triflate is present. The anionic counter ions of the guanidinium groups could be changed by working either in acetic acid or hydrochloric acid. In this way, two chitosan derivatives, namely N-guanidinium chitosan acetate (GChAc) and N-guanidinium chitosan chloride (GChCl), were produced. The materials were investigated by 13 C solid state NMR, FT-IR spectroscopy, SEM and TEM analysis and compared with the parent chitosan. The relaxation behavior of parent chitosan and new chitosan derivatives has been investigated by dielectric spectroscopy over wide temperature and frequency ranges, indicating that local motion is affected by counter ions. Due to these features, these materials are interesting candidates as high-power electrical materials for green technological applications.
Domains
Material chemistry
Origin : Files produced by the author(s)