Fabrication and Characterization of Completely Biodegradable Copolyester-Chitosan Blends: I. Spectroscopic and Thermal Characterization

Chitosan was prepared from shells of locally available fresh water prawns with variation of sodium hydroxide concentration and reaction time. The biopolymer was melt-mixed with a commercially available biodegradable polymer, the poly(butylene adipate-co-terephthalate) (PBAT). The chitosan and blend films were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The glass transition temperature (Tg) and melting point of the materials remained unchanged implying complete incompatibility of the blend components. Kinetic study showed that activation energy of the degradation process, i.e., thermal stability of the blends, decreased with increasing chitosan content in the blends. As the thermal properties of all the samples were found to be identical, it can be concluded that there was no effect of the added chitosan on the crystallization and melting behavior of the PBAT.