Infrared spectroscopy and thermal analysis of chitosan and its derivatives

Chitosan was prepared from crab shell. Different derivatives of chitosan e.g. phosphate, cyanoethyl and carboxymethyl chitosan are prepared. Molecular structure of chitosan and its derivatives was fallowed by infrared spectroscopy. A new band at 1715cm -1 (carboxyl group), at 2253cm -1 (cyano group) and at 1200cm -1 for (c-o-p) in spectra of carboxymethyl chitosan, cyanoethyl chitosan and chitosan phosphate respectively. The thermal analysis of chitosan and its derivatives was carried out. The major decomposition temperatures of cyanoethylated chitosan and phosphorylated chitosan are higher than chitosan and carboxymethyl chitosan. Also, the calculated activation energies of cyanoethylated and phosphorylated chitosan are higher than the chitosan and carboxymethyl chitosan.