Mechanical performance of biocomposites based on PLA and PHBV reinforced with natural fibres – A comparative study to PP

In the given research paper, the effects of reinforcing polylactid (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) biopolymers on the mechanical performance were studied. Both PLA and PHBV were compounded with man-made cellulose, jute and abaca fibres. The test bar specimens were processed via injection moulding. Various testing methods, including tensile and impact tests, were used to investigate the composites’ mechanical performance. Scanning electron microscopy was carried out to study the fibre–matrix interphasial adhesion. To determine the fibre-size distribution, optical microscopy was used. Finally, the obtained results were compared to composites on PP basis with the same reinforcing fibres.The reinforcing with fibres increased the tensile stiffness and strength significantly; however, depending on the fibre type, different improvements of the mechanical parameters were achieved. The main enhancement was realised in impact and tensile strength by reinforcing biopolymers with man-made cellulose fibres. SEM photographs show a largely differing fibre/matrix bonding for PLA and PHBV compared to PP composites. The broadest fibre-size distribution can be found in abaca composites.