Characterization of polymer complexes by thermal and IR spectral analyses

The characterization of polymer complexes were studied by thermal and infrared (IR) spectral analyses from room temperature to 1000 degreesC and from wave number 4000 cm(-1) to 200 cm-l, respectively. The polymer complexes were those prepared from cellulose ether (e.g., carboxymethyl cellulose and hydroxyethyl cellulose) with some transition metals (e.g., CrCl3, FeCl3, CuCl2, CoCl2, and NiCl2). The thermal analysis measurements, such as activation energy (E-a) and order of degradation (n), were calculated from nonisothermal thermogravimetric analysis, using the Coats-Redfern equation and the least squares method. The results obtained show that the complexation of cellulose ether with most mentioned metal ions improved their thermal stabilities. There is a relationship between the measurements of thermal analysis and the degree of ligand-metal-sigma bond (nephlauxetic parameter, beta), electronegativity of the metal cation, and the chelating sites of the ligand. The IR-spectra measurements, such as the shift of the band maximum, correspond to the stretching vibration of OH, the mean strength of the hydrogen bond, and the degree of crystallinity, evidence to some extent of the results of thermal analysis, especially the case of carboxymethyl cellulose-metal complexes.