Mechanical properties and biodegradation of biocomposites based on poly (hydroxybutyrate-co-valerate) and alfa fibers

Abstract

In recent years, most of the scientific research had focused on developing environment-friendly biodegradable materials after being used. There are two ways to do that: the first consists of the use of biodegradable plastics, and the second is the incorporation of biodegradable fibers in polymers. The main objective of this paper is to develop eco-friendly biodegradable biocomposites and to make their characterization. We devoted significant attention to investigate the use of alfa fiber as reinforcement in Poly (hydroxybutyrate-Co-valerate) (PHBV) material. The effects of fiber content and fiber treatment, as well as the biodegradation behavior of elaborated composites, have been investigated. From the main results, we observed some morphological changes that occurred on the fiber surface after chemical treatment. The use of fibers in PHBV increases the modulus but not necessarily improves the tensile strength of resulting composites but remains dependent on the interfacial adhesion. Alkali treatment of alfa fibers leads to improve the tensile strength and the rigidity of PHBV/alfa composites. SEM micrographs highlighted differences in microstructure of untreated and treated composites indicating that fiber-treatment also enhances the quality of the interface between the thermoplastic matrix and alfa fibers. In terms of degradability characteristics, the treated composites were highly biodegradable compared to both neat PHBV and untreated composites when subjected to water absorption in distilled and seawater. Also, elaborated composites undergo significant degradation into seawater, indicating their environmentally friendly character.