Mines ParisTech, Centre de Mise en Forme des Matériaux - CEMEF(1), UMR CNRS/Ecole des Mines de Paris 7635, CS 10207, 06904 Sophia-Antipolis, France.
Mines ParisTech, Centre de Mise en Forme des Matériaux - CEMEF(1), UMR CNRS/Ecole des Mines de Paris 7635, CS 10207, 06904 Sophia-Antipolis, France.
Carbohydr Polym. 2014 May 25;105:237-43. doi: 10.1016/j.carbpol.2014.01.085. Epub 2014 Feb 2.
Cellulose solubility phase diagrams in two binary solvents based on 1-ethyl-3-methylimidazolium acetate (EmimAc) mixed with water and with dimethylsulfoxide (DMSO) were built. The minimal amount of EmimAc molecules needed to dissolve cellulose is 2.5-3moles per anhydroglucose unit. This proportion allows calculation of the maximal cellulose concentration soluble in EmimAc-DMSO at any composition; in EmimAc it is around 25-27wt%. Water forms hydrogen bonds with EmimAc and thus competes with cellulose for ionic liquid; the solubility of cellulose in EmimAc-water is much lower than that in EmimAc-DMSO. Hydrodynamic properties of cellulose in two solvent systems were compared. In EmimAc-DMSO cellulose intrinsic viscosity practically does not depend on DMSO content as predicted by the phase diagram. The intrinsic viscosity in EmimAc-water first increases with water content due to cellulose self-aggregation and then abruptly decreases due to coagulation.
建立了基于 1-乙基-3-甲基咪唑醋酸盐（EmimAc）与水和二甲基亚砜（DMSO）的两种二元溶剂中纤维素溶解度相图。溶解纤维素所需的最小 EmimAc 分子数量为每一个脱水葡萄糖单元 2.5-3 摩尔。这个比例允许计算任何组成下 EmimAc-DMSO 中可溶解的最大纤维素浓度；在 EmimAc 中，约为 25-27wt%。水与 EmimAc 形成氢键，因此与纤维素竞争离子液体；纤维素在 EmimAc-水中的溶解度比在 EmimAc-DMSO 中低得多。比较了纤维素在两种溶剂体系中的流体力学性质。在 EmimAc-DMSO 中，纤维素的特性粘度实际上不随 DMSO 含量而变化，这与相图的预测一致。在 EmimAc-水中，由于纤维素的自聚集，特性粘度最初随含水量增加而增加，然后由于凝聚而急剧下降。
