Quantitative NMR investigation on the low-temperature dissolution mechanism of chitin in NaOH/urea aqueous solution
作者： Geying Ru , Huan Luo , Xinmiao Liang , Liying Wang , Chaoyang Liu
DOI: 10.1007/S10570-015-0667-2
关键词: Bioorganic chemistry 、 Atmospheric temperature range 、 Ternary operation 、 Urea 、 Aqueous solution 、 Dissolution 、 Chitin 、 Chemistry 、 Phase (matter) 、 Inorganic chemistry
摘要: The low-temperature dissolution mechanism of chitin in NaOH/urea aqueous solution has not been well established yet, especially at a temperature that lowers the crystallization both NaOH and urea. Using multiple nuclei (H-1, N-15 Na-23) nuclear magnetic resonance (NMR) methods, we find ternary NaOH/urea/D2O system, different from fully frozen binary NaOH-D2O exhibits solid-liquid phase coexistence below -40 degrees C, residual liquid consists certain concentrations (10 wt%), urea (13 wt%) D2O C. Our NMR results further demonstrate dissolves (containing 5-10 wt% 8-12 urea) low temperatures (-40 -70 C). An important role is enhancing stability solutions then increasing range chitin, thus providing an essential environment for dissolution.
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