Study on the thermal degradation of chitosan-Cu/Ni/Mn complexes

Abstract

AbstractThe thermal degradation of chitosan-Cu/ Ni/ Mn complexes at different heating rates in nitrogen was studied by thermogravimetric analysis (TGA) in the temperature range 30-500 °C. Fourier transform-infrared (FTIR) was utilized to determine the microstructure of chitosan-metal complexes. The results of FTIR show that there are coordinating bonds between chitosan and cupric, manganese, nickel ions. The results of thermal analysis indicate that the thermal degradation of chitosan-Cu/ Mn/Ni complexes is a two-step reaction, which is related to water loss from the material, the deacetylation of the main chain and the cleavage of glycosidic linkages of chitosan, respectively. Characteristic temperature increases with the increment of heating rate and the impact of coordination of metal ion on the thermal degradation of chitosan is very significant. The kinetic parameters were determined by using Flynn-Wall-Ozawa method. The results show that the activation energy of the complexes is different but the variable tendency is similar