Innovative flax tapes reinforced Acrodur biocomposites: A new alternative for automotive applications

•Evaluation of mechanical properties of long nonwoven flax tapes.•Process optimization of UD flax tape reinforced composite.•Study of thermal and mechanical behavior of UD composites made of nonwoven flax tapes and Acrodur resin.•Good thermal stability of the mechanical properties of the composite.

Flax Acrodur biocomposites are elaborated with an innovative flax reinforcement consisting of long technical fibers unidirectionally arranged without any weft and twist. The fibers cohesion is performed by using a new process consisting by reactivating the pectin cement. A polyester thermoset matrix (Acrodur) is used to impregnate the flax reinforcement and to produce unidirectional (UD) laminates. The relationship between the main process variables (drying, fibers content, densification and curing parameters) and the properties of the biocomposites is investigated. The optimized biocomposites have an elastic modulus of 18 ± 1 GPa with 55% wt.% flax fiber content and a low density of 0.93 g/cm3. The thermal stability of the developed biocomposites is also investigated by Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA) and Dynamic Mechanical Analysis (DMA). DMA results show a slight change of the storage modulus in a range of temperature from 23 °C to 160 °C. The appropriate processing parameters for the biocomposites are established. The developed flax tapes reinforced Acrodur biocomposites have a potential to be integrated for automotive applications thanks to their high stiffness/weight ratio and environmental advantages.