Mechanical properties of PLA composites with man-made cellulose and abaca fibres

PLA biocomposites with abaca and man-made cellulose fibres were processed by using combined moulding technology: two-step extrusion coating process and consecutively injection moulding. By adding 30 wt% of man-made cellulose, the Charpy impact strength at ambient temperature increased by factor 3.60, compared to unreinforced PLA. Tensile strength rose by factor 1.45 and stiffness by approx. 1.75. Reinforcing with abaca fibres (30 wt%) enhanced both E-Modulus and tensile strength by factor 2.40 and 1.20, respectively. The Charpy A-notch impact resistance of PLA/abaca could be improved by factor 2.4. SEM photographs show fibre pull-outs from the polymer matrix. The fibre orientation was analysed via optical microscopy. The after-process fibre length was significantly affected already during compounding process.