From the view of sustainable development, the new materials associated with re­newable source, low toxicity, high performance and environmental biodegradability

after disposal are enormously explored. The concerns over new materials from re­newable resource have recently increased because of the economic consequences of depleting petroleum resources, the demands from industrialists and customer for high performance lightweight low-cost materials and the environmental reg­ulations.1,2 From biomass, polymers can be obtained as native biopolymers, raw materials for monomers and bio-engineered biopolymers. Polysaccharides such as cellulose, starch, chitosan/chitin, etc. are the abundantly available biopolymers on the planet earth. They are replacing the materials for many industrial applications where synthetic polymers have been materials of choice, traditionally. As the na­tive biopolymers are not conventionally processable, research efforts have been fo­cused on the processing and meeting the requirements of particular applications. For packaging, the polymeric materials must exhibit flexibility, transparency, water and gas barrier properties, biodegradability (after disposal) antimicrobial, thermal and mechanical properties whereas surface adhesion (hydrophilicity), biocompatibility, biodegradability and dimensional stability.

Since natural biopolymers exhibit poor mechanical and thermal properties and processability they are very often blended with synthetic polymers synthetic biopolymers such as, polylactic acid and polycaprolactone and reinforced with par­ticulates.3 With the recent breakthroughs on nanoscience and nanotechnology, which allow tuning the materials properties at nano-scale level, the biobased nanocompos­ites are explored as renewable biomaterials.4,13 Hence, this chapter focuses on the recent developments in biobased nanocomposites based on chitosan and cellulose nanocrystals where both matrix and filler that are biologically renewable (Fig. 16.1).

The packaging materials based on polymer nanocomposites are recently pre­ferred not only for extending the shelf-life of food products but also for improving

the quality of food by acting as a carrier of some active substances such as antioxi­dants and antimicrobials.14 Owing to their biocompatibility, they are also explored for biomedical applications (as drug delivery system, wound dressing and biore­sorbable materials and low cytotoxic scaffolds for tissue engineering).1518