Improvement in mechanical and physical properties of starch-based films provided by cellulose nanocrystals extracted from rice straw

Abstract

Films based on starch (ST) have been widely used for food packaging; however, it is necessary to improve their mechanical properties. In this context, eco-friendly starch films incorporated with cellulose nanocrystal (CNC) were prepared using the casting method. CNCs were isolated using acid hydrolysis from rice straw (RS) as raw material and characterized by FESEM, TEM, FIIR, XRD, TGA and zeta potential analyzer. The isolated CNC presented a rod-like structure, high crystallinity (75%) with a diameter of around 12 nm. Subsequently, the starch-based films reinforced with various concentrations of CNC (2, 5, 10, and 15 wt%) were characterized for their morphological features, mechanical, barrier, and thermal properties and compared with control film. It was shown that the addition of CNCs to the film improved the mechanical properties and decreased the water vapor permeability, as important characteristics in food packaging materials.