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 foll owed by casting onto glass plates. X-ray diffraction patterns of the f ilms showed a gradual transition from partially crystalline cellulose to non-crystalline chitosan with increasing chitosan content. The tens ile 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 c ontents of 10-20%. Chitosan in the blend films showed increased resist ance to extraction with acetate buffer (pH 4.5). These results suggest the occurrence of specific interactions between cellulose and chitosa n molecules, probably based on the structural similarity. Solute perme ability in the blend films was greater than that for pure cellulose or chitosan film.