Rapid Dissolution of Cellulose in LiOH/Urea and NaOH/Urea Aqueous Solutions

Abstract Summary: Rapid dissolution of cellulose in LiOH/urea and NaOH/urea aqueous solutions was studied systematically. The dissolution behavior and solubility of cellulose were evaluated by using 13 C NMR, optical microscopy, wide‐angle X‐ray diffraction (WAXD), FT‐IR spectroscopy, DSC, and viscometry. The experiment results revealed that cellulose having viscosity‐average molecular weight ( $\overline M _\eta $ ) of 11.4 × 104 and 37.2 × 104 could be dissolved, respectively, in 7% NaOH/12% urea and 4.2% LiOH/12% urea aqueous solutions pre‐cooled to −10 °C within 2 min, whereas all of them could not be dissolved in KOH/urea aqueous solution. The dissolution power of the solvent systems was in the order of…