Can bamboo fibres be an alternative to flax fibres as materials for plastic reinforcement? A comparative life cycle study on polypropylene/flax/bamboo laminates

Although flax fibres are largely used to reinforce plastic, the quality of these fibres depends on the cultivation conditions, moreover, the global production volume of these fibres is also limited. The main aim of this current work was to investigate the feasibility of replacing flax fibres with bamboo fibres for reinforcing thermoplastics in terms of mechanical and environmental performance of both fibres. Two types of bamboo fibres, bamboo original fibres (BOF) and bamboo viscose fibres (BVF) and flax fibres as reference were used to reinforce polypropylene (PP). The composites were fabricated into laminates using manual stacking and hot pressing and the mechanical properties (tensile, flexural and impact) of the composites were evaluated. In order to evaluate the environmental performance of these composites life cycle assessment approach was conducted which showed that the composites reinforced with bamboo fibres were eco-friendlier as compared to the composites with flax fibres. However, the flax fibre-reinforced composite showed better mechanical performance. The BOF/PP composites showed better life cycle environmental performance as compared to both flax/PP and BVF/PP composites. Finally, a compatibilizer, i.e., maleic anhydride grafted polypropylene, was added which resulted in better mechanical and environmental performance of the bamboo fibre reinforced composites. Comparison between the environmental impacts of different disposal routes for the composites demonstrated that incineration and recycling are more environmental friendly disposal practises than placing waste in a landfill.