Direct ink writing of polymer‐based materials—A review

Abstract Additive manufacturing (AM) is widely recognized for its flexibility, structural complexity, customizability, and sustainability. Within the realm of AM technology, direct ink writing (DIW) stand out due to its material diversity, high resolution, and capacity for free‐form design. It enjoys widespread applications in biomedicine and engineering, making it a key advanced manufacturing method for crafting design‐free, multifunctional, and stable items. Herein, a review of the DIW of polymer‐based materials is presented. It starts with an overview of the various fillers in polymer composites, followed by an in‐depth discussion of the diverse methods for customizing ink for DIW across different material classes. Subsequently, it delves into the emerging applications of DIW polymer‐based materials, encompassing their utility in biology, electrical energy storage, electronics, and robotics. Finally, the review addresses the current challenges and prospects associated with DIW, aiming to elucidate potential pathways for future innovations. Highlights DIW is one of the most popular techniques in 3D printing. Describes the application of polymer‐based materials in DIW in recent years. Outlines advances in DIW of polymer‐based composites, hydrogels, and 4D printing. Outlines the myriad of applications for DIW of polymer‐based materials. Discusses current challenges and outlooks to provide guidance for future.