Plant fibre-reinforced polymers: where do we stand in terms of tensile properties?

This article reviews the tensile properties of various plant fibre-reinforced polymers reported in literature. We critically discuss the use of plant fibres as reinforcement for the production of bio-based, renewable or green polymer composites. The tensile properties of these composites are compared against various (non-)renewable engineering/commodity polymers and commercially available randomly oriented glass fibre-reinforced polymers (GFRP). Composites containing random short plant fibres possess similar properties to randomly oriented GFRP at a lower overall part weight. Unidirectional plant fibre-reinforced polymers offer better performance than randomly oriented GFRP and have the potential to be adapted in applications requiring better mechanical performance, especially in applications where the use of costly synthetic fibres might be less attractive. Plant fibres can also be regarded as fillers to replace the more expensive polymers and improve the green credentials of the final composite parts. These features may motivate the industry to move towards plant fibre-based products.