Mechanical characterization and damage events of flax fabric-reinforced biopolymer composites

Natural fibre-reinforced biopolymer composites are of special interest because they are entirely bioresourced, recyclable and biodegradable. Poly(lactic acid) (PLA), poly(hydroxybutyrate- co-hydroxyvalerate) (PHBV) and poly(butylene succinate) (PBS) are among the most known environment-friendly biodegradable thermoplastics. Unfortunately, they present unbalanced mechanical characteristics when they are taken separately. The aim of this work is to overcome this problem using a blending process accompanied with fibre reinforcement. For this purpose, entirely biodegradable composite materials were fabricated and characterized. These biocomposites are based on two different ternary PLA/PHBV/PBS blends reinforced with twill flax fabrics and fabricated using extrusion and film-stacking techniques. Monotonic and cyclic load–unload tensile tests followed by acoustic emission and scanning electron microscopy observations were performed. In particular, the obtained biocomposites present interesting mechanical properties with a tensile modulus of 20 GPa and an ultimate tensile strength of 110 MPa.