Polysaccharide films, also referred to as carbohydrate-based
films, are hydrophilic polymers and therefore exhibit very low
moisture barrier properties.
Cellulose and starch such as polysaccharides are of prime
interest as biopolymers because of their availability and rather
low cost, but the low elasticity of the materials is an important
drawback that limits their application.
Polysaccharides films are include starch and starch
derivatives, cellulose derivatives, alginate, pectin, chitosan,
carrageenan, and various gums.
The major mechanism of film formation in the polysaccharide
films is the breaking apart of polymer segments and reforming
of the polymer chain into a film matrix or gel by evaporation of
a solvent creating hydrophilic and hydrogen bonding.