Progress in nano-biocomposites based on polysaccharides and nanoclays

The last decade has seen the development of an alternative chemistry, which intends to reduce the human impact on the environment. The polymers are obviously involved into this tendency and numerous bio-sourced plastics (bioplastics), such as polylactide, plasticized starch, etc., have been elaborated. However, even if a lot of commercial products are now available, their properties (mechanical properties, moisture sensitivity) have to be enhanced to be really competitive with the petroleum-based plastics. One of the most promising answers to overcome these weaknesses is the elaboration of nano-biocomposites, namely the dispersion of nano-sized filler into a biopolymer matrix. This review reports the last developments in nano-biocomposites based on polysaccharides and nanoclays. The main elaboration strategies developed in starch, chitosan, cellulose acetate and pectin based nano-biocomposites elaborated with montmorillonite as the nanofiller are exposed herein. The corresponding dispersion state and properties are discussed. (C) 2009 Elsevier B.V. All rights reserved.