Innovative and Sustainable Advances in Polymer Composites for Additive Manufacturing: Processing, Microstructure, and Mechanical Properties

Additive manufacturing (AM) has revolutionised the production of customised components across industries such as the aerospace, automotive, healthcare, electronics, and renewable energy industries. Offering unmatched design freedom, reduced time-to-market, and minimised material waste, AM enables the fabrication of high-quality, customised products with greater sustainability compared to traditional methods like machining and injection moulding. Additionally, AM reduces energy consumption, resource requirements, and CO₂ emissions throughout a material’s lifecycle, aligning with global sustainability goals. This paper highlights insights into the sustainability of AM polymers, comparing bio-based and traditional polymers. Bio-based polymers exhibit lower carbon footprints during production but may face challenges in durability and mechanical performance. Conversely, traditional polymers, while more robust, require higher energy inputs and contribute to greater carbon emissions. Polymer composites tailored for AM further enhance material properties and support the development of innovative, eco-friendly solutions. This Special Issue brings together cutting-edge research on polymer composites in AM, focusing on processing techniques, microstructure–property relationships, mechanical performance, and sustainable manufacturing practices. These advancements underscore AM’s transformative potential to deliver versatile, high-performance solutions across diverse industries.