Towards Sustainable Regenerated Cellulose Fibres: A Review of Conventional Spinning Technologies and Advancing Ionic Liquid–DMSO Solvent Systems

Manufactured fibres account for over 70% of fibre consumption in the global textile market, with production centred on petrochemical-derived synthetics and regenerated cellulose fibres (RCFs). RCFs offer the opportunity to utilise alternative cellulose sources such as various plants, paper products, and postconsumer textiles, reducing the reliance on natural fibres such as cotton, which demands extensive land and water resources. The majority of RCFs are still produced using the viscose process, a method associated with high chemical, water, and energy usage. Employing ionic liquids (ILs) as an alternative solvent for cellulose dissolution is associated with desirable qualities such as the ability to capture and reuse the solvent, limited need for the pretreatment of cellulose, and alignment with green chemistry principles. At present, limited review articles have investigated the process of spinning fibres utilising ionic liquids as the dissolution solvent, particularly in combination with dimethyl sulfoxide (DMSO). To further understand the potential of RCFs, this review investigates existing cellulosic spinning technologies and the use of ILs, with particular attention given to IL–DMSO systems. By examining their combined behaviour and properties, this paper highlights their potential to advance sustainable textile manufacturing.