Role of chitin nanocrystals and nanofibers on physical, mechanical and functional properties in thermoplastic starch films

The purpose of this work was to evaluate and compare the role of different nano-chitin morphologies on the structural and functional properties of thermoplastic starch-based films prepared by casting-evaporation approach. The introduction of chitin nano-objects - nanocrystals (CHNC) and nanofibers (CHNF) in concentrations of 5-20% - in thermoplastic starch-based matrices resulted in the enhancement of the final properties of the nanocomposite films in a morphological-dependent manner. The obtained data clearly demonstrate that the nanocomposite films elaborated with chitin nano-objects showed superior mechanical, thermal, barrier and antifungal properties as compared to those prepared with unfilled thermoplastic starch films. Furthermore, chitin nano-objects content, shape and size, were found to be an important role to the final properties of the thermoplastic starch nanocomposite films. Our findings highlight the potential use of such chitin nano-objects in thermoplastic starch-based matrices to be applied in functional food coatings and packaging. (C) 2014 Elsevier Ltd. All rights reserved.