| Starch and chitosan films are both known to be effective barriers to gas permeation. Being naturally abundant, renewable, and biodegradable, starch and chitosan films have the potential to replace petroleum-based materials for food packaging applications. However, the gas permeability of starch-chitosan blend films has not been studied extensively. In order to characterize starch-chitosan blend films for food packaging application, the permeabilities of N2 , O2 and CO2 in the blend films were studied at different operating conditions (e.g., relative humidity, chitosan content in the films, cross membrane pressure, and temperature).;The gas permeation was measured using the traditional volumetric technique. Gas permeation through films containing different amounts of chitosan was measured at ambient temperature and at a cross membrane pressure of 60psi. In addition, pure chitosan was also tested at a high relative humidity where the gas was saturated with water vapor. The effects of temperature and cross membrane pressure on the gas permeability were studied with starch-chitosan blend films and pure chitosan films as well. It was found that an increase in pressure and/or temperature increased the permeability, and the temperature dependence of permeability followed the Arrhenius relation, from which activation energy of permeation was evaluated. The starch-chitosan blend films with approximately 60wt% chitosan showed the best gas barrier property and the highest activation energy for permeation. |
