X-ray study of chitosan films☆

Abstract The structure of chitosan films prepared from solutions in dichloracetic and acetic acids has been investigated. The films in the “salt” form are unoriented. The “salt” form prepared from dichloracetic acid has a chitin type structure, while the “salt” film prepared from acetic acid has a chitosan type structure. Films in the “alkali” form have a chitosan type structure and planar orientation. Dispositions of macromolecular axes are equiprobable in any direction in the film planes. The “alkali” films prepared from 2% solutions in 0·22 m dochloracetic acid are the best oriented, and their degree of crystallinity and strength values are highest. Their structure is similar to that of chitosan layers obtainable by alkali treatment of natural oriented layers of shell chitin.