Lutidinium-based ionic liquids for efficient dissolution of cellulose

• Published in: New journal of chemistry 2019, Vol.43 (5), p.2299-236
• Main Authors: Samikannu, Rakesh, Shukla, Shashi Kant, Samikannu, Ajaikumar, Mikkola, Jyri-Pekka
• Format: Article
• Language: English
• Subjects: Carbon 13; Cellulose; Cellulose dissolution; Cross polymerization/magic angle spinning C NMR; Crystal structure; Crystallinity; Dissolution; Ionic Liquids; Morphology; NMR spectroscopy; Scanning electron microscopy; Spectrum analysis; Stability analysis; Thermal stability; Thermogravimetric analysis; viscosity; X-ray diffraction
• ISSN: 1144-0546; 1369-9261; 1369-9261
• DOI: 10.1039/c8nj04698k

Herein, we have studied the potential of lutidinium-based ILs (1-allyl-3,5-dimethylpyridinium chloride [3,5-ADMPy]Cl and 1-allyl-3,4-dimethylpyridinium chloride [3,4-ADMPy]Cl) in the dissolution of cellulose, and their structures were confirmed by 1 H and 13 C NMR spectra, respectively. [3,5-ADMPy]Cl exhibited the highest capacity in cellulose dissolution. In fact, it dissolved 20 wt% of cellulose within 12 min and 26 wt% of cellulose in 35 min at 118 °C. The crystallinity and morphology of native and regenerated cellulose were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM) and CP/MAS 13 C NMR spectroscopy. These techniques clearly suggest that the crystallinity of cellulose is reduced upon treatment in lutidinium-based ILs. The thermogravimetric analysis (TGA) showed that regenerated cellulose had thermal stability close to that of native cellulose. Herein, we have studied the potential of lutidinium-based ionic liquids in the dissolution of cellulose as confirmed by the X-ray diffraction (XRD), scanning electron microscopy (SEM) and 13 C CP/MAS NMR, spectroscopic methods.