The effect of additives on the thermal degradation of cellulose acetate

The thermal degradation of pure cellulose acetate and cellulose acetate with mono ammonium phosphate and boric acid as physically incorporated additives, was investigated using thermogravirnetry analysis, thermal volatilization analysis and characterization of the degradation products by infrared spectroscopy. The additives modified the degradation process by decreasing the thermal stability of the polymer, enhancing the char and reducing the volatile formation. The addition of ammonium phosphate and boric acid together showed a synergistic effect in increasing char quantity. In this case a decrease in thermal stability was not observed. The analysis of degradation products showed that the cellulose acetate decomposition occurred by scission of glycosidic linkages followed by pyranose. ring rupture and acetic acid evolution. Kinetic parameters, like activation energy, were calculated following the Ozawa method using dynamic thermogravimetric data. (C) 2003 Elsevier Science Ltd. All rights reserved.