Biodegradable nanocomposites based on poly(hydroxyalkanoates)

Abstract

This chapter aims at highlighting on recent development in preparation, characterization, properties, crystallization behaviors, thermal degradation, melt rheology, controlled biodegradation, and future application possibilities of polyhydroxyalkanoates (PHA) biodegradable polymers and their nanocomposites in presence of various nanoparticles. Biodegradable materials are attracting considerable interest in materials science research. Various types of nanofillers ranging from zero-to three-dimensions, e.g. spherical particles, nanotube/nanowire, platelets like layered silicates are incorporated to reinforce the polyhydroxyalkanoate matrices. Different routes to prepare/synthesize PHA nanocomposites are discussed; the effect of nanofillers on the structure, properties, and processing behaviour of PHA is accounted elaborately. Works on intercalated or exfoliated structure have been presented in case of layered silicate nanofillers. One of the important aspects of this class of material is biodegradation. The biodegradation behaviour in presence of various nanoparticles is described. Controlled biodegradation is another prime facet of this review. Finally, the new family of composite materials frequently exhibits remarkable improvements of mechanical and material properties when compared with pristine polymers or conventional micro-and macro-composites. Improvements can include a high storage modulus both in solid and molten states, increased tensile properties, decrease in gas permeability, thermal stability, increase and regulated biodegradation rate. © Vikas Mittal 2011. All rights reserved.