Preparation and characterization of hexanoyl chitosan/polylactide blend films

In the present contribution, blend films of hexanoyl chitosan (H-chitosan) and polylactide (PLA) were prepared by the solution-casting technique from the corresponding blend solutions in chloroform. Fourier-transformed infrared spectroscopy results indicated no significant interaction between H-chitosan and PLA molecules. The thermal degradation behavior of the as-prepared blend films was found to be intermediate to those of the pure components. Only the blend film having the H-chitosan content of 20 wt% exhibited the degradation temperature greater than those of the pure components. All of the blend films exhibited one composition-dependent glass transition temperature, indicating partial miscibility between H-chitosan and PLA molecules in the bulk amorphous phase. The apparent degree of crystallinity of the PLA component in the blends was found to decrease monotonically with increasing H-chitosan content. Both the tensile strength at break and the Young's modulus of the blend films were found to decrease from that of the pure PLA to that of the pure H-chitosan with increasing H-chitosan content.