The production of enormous quantities of waste electrical and electronic equipment (WEEE) is taking place globally, especially in industrialized countries. WEEE contains large quantities of critical raw materials (CRM), such as metals, polymers, glass etc, that can be isolated, recovered, and recycled, leading to substantial environmental benefits, by decongesting landfills of potentially hazardous materials and compounds thereof. Printed Circuit Boards (PCB) are abundant practically in all WEEE, to mechanically support and electrically connect the components, using conductive tracks [1]. PCB are composed of three types of materials: a non-conductive substrate, printed conductive tracks and components mounted on the substrate. The substrate typically contains glass fiber-reinforced epoxy resin. Printed conducting tracks and components mounted on the substrate are comprised of critical metals. Copper (Cu) is one of the most abundant metals in PCB and one of the most widely used critical metals, as it can offer increased electric, thermal and conductivity and antibacterial properties [2]. Nickel (Ni) is mainly used to prevent migration and diffusion between Cu and gold existing in PCB, as well as to protect the Cu layer from oxidation and to enhance conductivity [3]. Their recycle and reusability is a highly ecological way of reintroducing critical metals back into the economy. The purpose of this study is the fabrication of polylactic acid (PLA) composite filaments with fillers derived from WEEE and the influence of each filler on the rheological, morphological, thermal and mechanical properties of final composite 3D-printed samples. The fabricated composite filaments, via Fused Deposition Modelling (FDM), a widely used method of Additive Manufacturing, had 5, 10 and 15% concentration of fillers such as glass-fiber-reinforced epoxy resin, named PCB, Cu and Ni. I Thermal properties were not greatly affected by the addition of fillers. PCB composites presented increased viscosity, whereas the addition of metals had a negative impact towards it. Finally, mechanical performance analysis showed that the mechanical properties of composites were enhanced compared to pure PLA, introducing a zero-waste and sustainable-by-design paradigm with significant potential towards upscaling.

[1] N. I. Onwughara, I. C. Nnorom, O. C. Kanno, and R. C. Chukwuma, International Journal of Environmental Science and Development, 2010, 1, 290–297.
[2] B. Podsiadły, A. Skalski, B. Wałpuski, and M. Słoma, Journal of Materials Science: Materials in Electronics, 2019, 30, 1236-1245.
[3] U. V. Aniekwe and T. A. Utigard, Canadian Metallurgical Quarterly, 1999, 38, 277-281.