Polylactic acid/recycled wind turbine glass fiber composites with enhanced mechanical properties and toughness

Abstract The amount of composite waste from decommissioned wind turbine blades grows rapidly and recycling solutions should be generated to overcome this environmental challenge. This research aims to further develop a recycling method to recover components of dismantled turbine blades by reusing them as reinforcement for new composites. Recycled short glass fibers from shredded blade composites are incorporated into polylactic acid (PLA) to fabricate a composite (15 wt% fiber) that could be used for 3D filament fabrication. To improve the mechanical properties of the composite, a coupling agent was employed to refine the interactions between PLA and recycled glass fibers at the interface of the two components and enhance the adhesion. Due to the inherent brittleness of PLA, which is aggravated with the addition of recycled glass fibers, a toughening agent involving chain‐end modification was incorporated into the composite to improve the toughness of the system. The concurrent outcome of the coupling agent and the toughener on the morphology, mechanical properties and thermal behavior of the composite was evaluated. The incorporation of 1,2,3,4‐butane tetracarboxylic acid and silane‐treating of the recycled fibers improved the strength by 30% and elongation at break and impact strength of the composite 3 and 2 times, respectively.