The effect of the crosslinking agent on physical and mechanical properties of Chitosan / Banana flour sheet

Abstract

This research studied the effect of the cross-linking agent on physical and mechanical properties of Chitosan / Banana flour sheets. The Chitosan / Banana flour sheets were prepared by compression molding at 130oC for 2 minutes, using 15% gelatinized banana flour with propane 1,2-diol (plasticizer) mixed with 1.5% chitosan solution and boric acid used as the cross-linking agent with varied amounts (0%, 0.5%, 1%, 1.5% and 2%) based on dry starch content. The mixture was stirred until compatible and then dried and reduced in size at room temperature. For the final step, the product was prepared by compression molding in order to study physical (compatibility, humidity and color parameter) and mechanical properties (tensile testing) of the sheets. The Chitosan / Banana flour sheets mixed with boric acid showed an increase in miscibility between banana flour and chitosan as seen in the SEM images and improved flexibility of the sheets. The results presented show that the incorporation of boric acid into the Chitosan / Banana flour sheet improved the compatibility, mechanical properties, humidity stability and appearance of the material, a cross-linking content of 1.5% gave the best overall improvement. With these improved properties this Chitosan / Banana flour sheet can be applied to be used as a biodegradable food packaging material.