Thermogravimetric analysis (TGA) plays an important role indetermining the thermal stability of these materials. The results ofthermogravimetric analysis for chitosan, PVA and their compositefilms are shown in Table 3 and Fig. 3. The TGA curve of chitosanexhibits a two-stage weight loss. The first stage was attributed tothe loss of adsorbed water and residual acetic acid, and it showedan approximate 9% loss in weight for the chitosan sample. The sec-ond stage (200–365◦C) was due to the degradation of chitosan,and during this process there was an approximate 45% loss in