13 - Polyhydroxybutyrate (PHB)-based blends and composites

Abstract

Polyhydroxybutyrate (PHB) is a hydrophobic material characterized by having a methyl as an alkyl substitution group. PHB is a biocompatible polymer, which results in it not being rejected by the body. Moreover, its assimilation generates nontoxic residues. This biodegradable polymer can be synthesized chemically or biologically. Several bacteria, cyanobacteria, and/or microalgae can be used to synthesize PHB intracellularly as an energy reserve. However, PHB is a fragile material, which limits some of its applications. Thus, the manufacture of blends with materials from natural sources, synthetic biodegradable polymers, and/or nonbiodegradable polymers is important to improve the physical, mechanical, and thermal properties of these materials. In addition, recent trends of PHB-based composites provide new perspectives on applications in health, food packaging, agriculture, and bioremediation. In this way, this chapter addresses the physical, chemical, and biological characteristics of PHB and the main methods of production of this polymer using chemical and biological syntheses. Furthermore, strategies for the application of PHB in composites and blends, as well as the applications of these materials in several areas, are explored in this chapter.