A Comprehensive Methodology to Support Decision-Making Towards Sustainability on Nanocomposite Materials in Additive Manufacturing Sector

Abstract

Innovative nanocomposite materials and resultant additive manufacturing products are necessary to be assessed for their carbon footprint towards top priorities of EU for plastics, including the European Green Deal principles and the Action Plan for Circular Economy. Life Cycle Assessment (LCA) is widely applied standardized methodology that aims to study potential environmental impacts of novel products. Nano-scale materials (NM) are usually dispersed in polymer to enhance their limited functional properties resulting in a spectrum of end-products for multiple applications. However, little information exists on their environmental impact. Within this context, this study presents a ‘cradle-to-gate plus end-of-life’ LCA approach, studying different types of 3D printing nanocomposite filaments across the supply chain. Three different types of polymer matrixes were examined: polyamide (PA), polypropylene (PP) and polylactic acid (PLA), additivated with three different types of nanomaterial additives: multiwall carbon nanotubes (MWCNTs), graphene oxide (GO) forms and graphene nanoplatelets (GNPs), considering lab-scale production. In addition, several different EoL scenarios have been examined for the materials. Finally, LCA findings are coupled with the performance (taken here as conductivity) of these new materials to assist the decision-making process for selecting efficient scenarios with the least environmental impact. The outputs of this examination enable identification of potential sustainability issues for novel nanocomposite materials at an early design stage, while also assisting in the definition of actions to mitigate such issues. Thus, LCA studies can generate knowledge on the environmental impacts of nano-enabled materials, while also serving as a valuable decision support tool towards optimizing material sustainability aspects.