Characterization of poly-hydroxybutyrate/luffa fibers composite material

Abstract

Luffa fibers were evaluated as a reinforcement material in poly-hydroxy-butyrate matrix composites. The treatments consisted of varying the incorporation percentage of mercerized and non-mercerized luffa fibers in a poly-hydroxybutyrate (PHB) matrix (5%, 10%, and 20% w/v). Composites made with PHB and reinforced with luffa fibers (treated and non-treated) were mechanically evaluated (tensile strength, Young’s modulus, and percentage of elongation at break), the surface morphology was described by using scanning electronic microscopy, and the degradability behavior of composites was obtained. According to the results, mechanical properties decreased when the percentage of fibers increased and no significant effects were observed when compared with mercerized fiber composites. Degradability tests demonstrated that the weight loss increased with increased fiber content in composites, independent of the applied pretreatments. Microscopy images exhibited that mercerization improved the fiber incorporation into the polymeric matrix, diminishing the “pull out” effect; the above-mentioned result was supported by using the Fourier-transform infrared spectroscopy technique, observing the reduction of lignin and hemicellulose peaks in mercerized fibers. Based on the composite mechanical performance and degradability behavior, it was concluded that this material could be used in the packaging sector as biodegradable secondary packaging material.

Polyhydroxybutyrate-Natural Fiber Reinforcement Biocomposite Production and Their Biological Recyclability through Anaerobic Digestion

“…Orange waste (Figure 1F), chitosan (Figure 1G), and sawdust (Figure 1H), however, presented in longer shapes, showing the pulled-out fibers and voids in the system. Similar poor interfacial bonding behavior in PHB composites has been reported in previous studies where starch [15] and lignocellulosic materials [11,33,34] were used as filler. By contrast, the structure of PHB reinforced with chitin and cellulose is preferable since the fibers were well blended in the PHB matrix, forming a homogenous agglomeration and distribution.…”

Green composites and their contribution toward sustainability: A review

“…99 Incompatibility between the hydrophobic polymer matrix and the hydrophilic fibers can create micro-voids, which might increase water retention. 100 Micro-gaps between polymer molecular chains also contribute to water absorption by allowing the inward diffusion of water molecules. 15 The absorbed water molecules severely affect the fiber-matrix interface.…”