Acylation of iminochitosan: Its effect on blending with cellulose acetate

Abstract Chitosan has many similarities to cellulose, but there are few good direct solvents for codissolving them. Cellulose is cheaper than chitosan, and a blend film of the two would be expected to exhibit the desirable properties of both these polysaccharides. The formation of chitosanic and cellulosic acyl derivatives is an attractive route for the preparation of these fibers and films. They are soluble in common organic solvents, and in many cases it is not difficult to regenerate cellulose or chitosan from these derivatives. However, it may be desirable to protect the amino group from these reactions. Iminochitosan was used in the present study for that purpose. Chitosan at four molecular weights was prepared using an HCl/isopropanol binary system. The hydrolyzed chitosan was allowed to react with salicylaldehyde via Schiff base formation. Acylation of iminochitosan was carried out by its reaction with different acid halides containing a varied number of carbon atoms in the presence of a catalyst. The main factors that affected the dissolution of acylated iminochitosan in different organic solvents are described. Films from blends of n‐butyryl iminochitosan with cellulose acetate were prepared and are described. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 727–734, 2007