PREPARATION OF CELLULOSE CHITOSAN BLEND FILM USING CHLORAL DIMETHYLFORMAMIDE

Cellulose-chitosan blend films with varied mixing ratios (0-100%) were prepared by dissolving the polymers in chloral/dimethylformamide followed by casting onto glass plates. X-ray diffraction patterns of the films showed a gradual transition from partially crystalline cellulose to non-crystalline chitosan with increasing chitosan content. The tensile strength and Young's modulus of the blend films were greater than those calculated by adding the values of the two components according to the blend ratios. Maxima in these properties appeared at chitosan contents of 10-20%. Chitosan in the blend films showed increased resistance to extraction with acetate buffer (pH 4.5). These results suggest the occurrence of specific interactions between cellulose and chitosan molecules, probably based on the structural similarity. Solute permeability in the blend films was greater than that for pure cellulose or chitosan film.