Nanoscale wall thickness means higher surface area to expose more functional groups for rapid water absorption. As the chitosan wall expanded after water absorption, it had potential to seal the microscale poresand retained the free water inside the pores. XRD patterns also showed that peak width of chitosan film was larger than that of raw chitosan powder, which indicated less crystalline and relativelylower amorphous chitosan percentage in the film .Thus, the OH and NH2hydrophilic groups are available for water absorption in contrast to the crystalline morphology where mostof the functional groups are concealed inside the crystal structure..Besides the solvent system, the chitosan concentration also hasan impact on the water uptake capacity of chitosan films.