Sustainable design and application of recyclable dialkylimidazolium dimethylphosphate ionic liquids for green cellulose fiber processing
Journal
Sustainable Chemistry and Pharmacy
Journal Volume
48
Start Page
102267
ISSN
23525541
Date Issued
2025-12
Author(s)
Abstract
Ionic liquids (ILs) are promising sustainable solvents for cellulose processing owing to their high solubility, thermal stability, and recyclability. However, conventional imidazolium-based ILs, such as 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc), are prone to C2-position side reactions and exhibit limited recyclability, which significantly constrains their industrial applicability. This study introduces a viable IL, 1-isopropyl-3-methylimidazolium dimethylphosphate ([iPMIM]DMP), featuring dual innovation: a branched isopropyl cation that enhances cellulose solubility through steric effects, and a low-pKa dimethylphosphate anion that suppresses side reactions and improves recyclability. Synthesized via a simple one-step route, [iPMIM]DMP exhibits excellent thermal stability, high cellulose solubility, and favorable rheological properties suitable for dry-jet wet spinning. Regenerated fibers prepared from paper-grade pulp show a tenacity of 36.90 cN/tex, comparable to industrial N-methylmorpholine N-oxide (NMMO)-based fibers. Moreover, [iPMIM]DMP can be efficiently recovered and reused over three dissolution–spinning cycles without performance loss, demonstrating strong chemical robustness. This work provides a practical and sustainable approach for recyclable ILs in cellulose fiber production.
Subjects
Dialkylimidazolium dimethylphosphate
Dry-jet wet spinning
Ionic liquid (IL)
Recycling
Regenerated cellulose filament
Publisher
Elsevier B.V.
Type
journal article