Natural biopolymer-based nanocomposite films for packaging applications

Abstract

Recent interest in environmentally friendly bio-based polymers coupled with an increased food safety awareness has resulted in various packaging technology advances, including the incorporation of different kinds of nanofillers into biodegradable biopolymers to improve their overall properties for improving shelf life and preventing microbial growth. Among the different nanofillers that have recently emerged, graphene's invention has catalyzed a multitude of novel material applications in different fields. Graphene has functionalized different biopolymers and has improved their mechanical, thermal, electrical, as well as, gas, and water vapor barrier properties, for potentially replacing petrochemical-based packaging materials that pose a great threat to the environment. The objective of this chapter is to provide comprehensive understanding of the different types of nanoreinforcement that are available for biodegradable packaging application, especially focusing on graphene oxide (GO), a graphene derivative nanofiller that is being extensively studied for packaging reinforcement. This chapter aims to draw a clear picture of synthesis and chemistry of bonding between graphene derivatives and biodegradable biopolymers suitable for packaging applications, like starch, cellulose, poly (lactic acid), and others. The methodology behind the chemical and physical changes during synthesis will be discussed, based on different spectroscopic characterization techniques, and the influence of chemical changes on resulting properties will also be highlighted. This chapter will also briefly go over other nanomaterials like clay, cellulose nanofibers, starch nanocrystals, and their usage in different biopolymers for packaging application. This will help to explain the synergy resulting from addition of nanomaterials, the use of different characterization techniques as well as the improvement in different properties.