Investigation of mechanical and physicochemical properties of additively manufactured underutilized wood‐<scp>PLA</scp> biocomposites

Abstract Despite Canada's abundant biomass resources, a significant portion remains underutilized due to a lack of large‐scale industrial applications. This research explores the utilization of low‐value biomass, specifically aspen fiber, in fused filament fabrication (FFF) to develop biocomposites. Various chemical treatments (NaOH, silane, and maleic anhydride (MA)) were applied to improve fiber compatibility with polylactic acid (PLA). Both untreated and treated fibers at 10 wt% loadings were blended with PLA and extruded into 3D printable filaments. Results showed that MA‐treated fiber‐based composites had around 15% higher tensile strength and modulus along with a 30% enhancement in storage modulus than untreated ones. Additionally, a 25% reduction in water uptake was witnessed in MA‐treated aspen‐derived composites. Furthermore, the effect of fiber loading on the mechanical performance of the composites was explored by producing aspen‐PLA composites with higher fiber weight percentages (10, 20, and 30). Despite successfully 3D‐printing biocomposites with up to 30 wt% fiber content without nozzle clogging, the mechanical properties deteriorated with higher fiber loading. All the findings highlight the untapped potential of underutilized biomass in the development of value‐added composites. Highlights Underutilized Aspen fiber was combined with PLA to develop biocomposites. Successfully 3D‐printed biocomposites with up to 30 wt% wood content The optimal printing temperature for FFF was found to be 220°C NaOH, silane, and maleic anhydride (MA) fiber treatments were applied. MA treatment was the most effective treatment for Aspen‐PLA biocomposite.