Challenges to Improve Extrusion-based Additive Manufacturing Process of Thermoplastics Towards Sustainable Development

This review aims to present the different approaches to lessen the environmental impact of the extrusion-based additive manufacturing (MEX) process of thermoplastic-based resins and protect the ecosystem. The benefits and drawbacks of each alternative, including the use of biomaterials or recycled materials as feedstock, energy efficiency, and polluting emissions reduction, have been examined. First, the technological option of using a pellet-fed printer was compared to a filament-fed printer. Then, common biopolymers utilized in MEX applications were discussed, along with methods for improving the mechanical properties of associated printed products. The introduction of natural fillers in thermoplastic resins and the use of biocomposite filaments have been proposed to improve the specific performance of printed items, highlighting the numerous challenges related to their extrusion. Various polymers and fillers derived from recycling were presented as feeding raw materials for printers to reduce waste accumulation, showing the inferior qualities of the resulting goods when compared to printed products made from virgin materials. Finally, the energy consumption and emissions released into the atmosphere during the printing process were discussed, with the potential for both aspects to be controlled through material selection and operating conditions. This article is protected by copyright. All rights reserved.