title: Effects of polymorphs on dissolution of cellulose in NaOH/urea aqueous solution.
abstract: This study focused on the effect of cellulose crystal type on the dissolution of cellulose in aqueous NaOH/urea. Cellulose I, II, IIII, and IVI were prepared and characterized. Subsequently, the solubility of these cellulose samples in aqueous NaOH/urea was tested and the mechanism was determined by a combination of (1)H NMR spectroscopy and differential scanning calorimetry (DSC). The results indicated that, compared with the degree of polymerization (DP) and crystallinity index of cellulose, the cellulose crystal type had greater impact on cellulose dissolution. Specially, the solubility of the cellulose I, II, and III was progressively decreased, probably due to different hydrogen bond network and packing energy in it. The ability of cellulose I, II, III, and IV to form hydrogen bonds with sodium hydroxides was nearly the same, while gradually increased when cellulose preparations were associated with urea. Moreover, all the cellulose solutions showed good thermal stability.
authors: MOE Key Laboratory of Wooden Material Science and Application, Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China.
authors: Xiong
authors: X
authors: Chen
authors: MOE Key Laboratory of Wooden Material Science and Application, Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China.
authors: Jinghuan
authors: J
authors: Chen
authors: MOE Key Laboratory of Wooden Material Science and Application, Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China.
authors: Tingting
authors: T
authors: You
authors: MOE Key Laboratory of Wooden Material Science and Application, Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China. Electronic address: wangkun@bjfu.edu.cn.
authors: Kun
authors: K
authors: Wang
authors: MOE Key Laboratory of Wooden Material Science and Application, Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China. Electronic address: xfx315@bjfu.edu.cn.
authors: Feng
authors: F
authors: Xu
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D003460:Crystallization; D012972:Sodium Hydroxide / Q000737:chemistry*; D012995:Solubility; D012996:Solutions / Q000737:chemistry; D014508:Urea / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D012996:Solutions; D014867:Water; D012972:Sodium Hydroxide; D014508:Urea; D002482:Cellulose
keywords: Cellulose; DP; NaOH/urea; Polymorphs