What are chitosan films?
When chitosan gels are dried, they form films in which the chitosan polymers are held together by the same forces as in the hydrogel, and residual water is also held inside the film. Chitosan films are transparent and can be very stable, but they dissolve in water. They are ideally suited as wound dressings, holding the wound humid but not too wet and, due to the anti-microbial properties of chitosans, also clean. These anti-microbial properties also make chitosan films useful for food packaging, where it is also important that they are permeable to gases and water vapor. The filmogenic properties of chitosans can be greatly enhanced or modified by chemically modifying the chitosan.