Thermomechanical and crystallization behavior of polylactide-based flax fiber biocomposites

In this work, the rheological, thermal and mechanical properties of melt-compounded flax fiber-reinforced polylactide composites were investigated. The effect of compounding on fiber length and diameter, and the relationship between fiber content and the crystallization behavior of the biocomposites, at various temperatures, were also examined. After melt-compounding, fiber bundles initially present were, to a large extent, broken into individual fibers and the fiber length was decreased by 75 %, while the aspect ratio was decreased by nearly 50 %. The crystallization half-time was found to decrease with increasing flax fiber content, and showed a minimum value at 105 °C for all systems. The elastic modulus was increased by 50 % in the presence of 20 wt% flax fibers. The addition of maleic anhydride-grafted polylactide had a positive effect on the mechanical properties of the biocomposite. This system is particularly interesting in the context of sustainable development as it is entirely based on renewable resources and biodegradable.