Use of Water-soluble Feedstocks in Material Extrusion Additive Manufacturing; Research background and challenges

Material extrusion additive manufacturing (MEAM) has emerged as a versatile and cost-effective technology for fabricating complex three-dimensional components. This review focuses on the integration of water-soluble feedstocks in MEAM, highlighting their potential for environmentally sustainable and efficient manufacturing. Water-soluble polymers such as polyethylene glycol (PEG) and polyvinyl alcohol (PVA) serve as critical binder components, enabling the use of water as a debinding agent, which minimizes reliance on hazardous solvents and reduces environmental impact. The composition and optimization of feedstocks-including the balance of polymers, powders, and additives-play a pivotal role in determining rheological behavior, extrusion performance, and the mechanical properties of green and sintered parts. Challenges such as maintaining mechanical strength, managing environmental sensitivity, and ensuring consistency in processing are addressed. Key insights into the relationship between particle morphology, binder molecular weight, and process parameters such as extrusion temperature and nozzle design are discussed. Figures and tables provide a detailed analysis of feedstock formulations, binder interactions, and their effects on material behavior. This paper provides a comprehensive overview of current advancements and limitations in using water-soluble feedstocks for MEAM, identifying future research opportunities aimed at enhancing process reliability, part quality, and sustainability. The findings aim to support the wider adoption of MEAM in diverse applications, from prototyping to industrial-scale production, leveraging innovative feedstock designs for more sustainable manufacturing practices.