Preparation and characterization of carboxymethyl-chitin/silk fibroin blend films

Abstract

CM-chitin/silk fibroin blend films were prepared by solvent casting method. The effects of CM-chitin to silk fibroin ratio and cross-linking agent on swelling behavior and mechanical properties of the blend films were studied. The blend films exhibited a change in the degree of swelling when the blend films were immersed in both acidic and alkaline solutions. The degree of swelling of the films increased as the CM-chitin content increased. It appeared that cross-linking occurred in the blend films reduced the swelling capacity of the films. For the study on effect of salt type, the films were immersed in various types of aqueous salt solutions, i.e., NaCl, LiCl, CaCl2, and FeCl3. Among these salts, the film immersed in NaCl, LiCl, and CaCl2 had higher degree of swelling than in FeCl3. The tensile strength increased with the increasing of the amount of cross-linking agent whereas the elongation at break decreased.