Modelling of mechanical properties of chitosan films

Abstract

Films were obtained preparing 3% (w/v) chitosan solutions in 1% (v/v) lactic acid using glycerol, sorbitol or polyethylene glycol at 0.25 to 0.50 mL/g of polymer as plasticizers. Film thickness, tensile strength, force at break, deformation and elongation were measured in order to evaluate the effect of molar mass and plasticizers concentration on mechanical properties values. Mathematical models with these factors were proposed. Films with polyethylene glycol had higher tensile strength and normalized force at break than those which glycerol or sorbitol, but less elongation or normalized deformation. In addition, the films were more elastic and with lesser force at break with the increase of plasticizer concentration.