Preparation and Rheological Properties of Cellulose Solutions from Different Solvents

Abstract:

      Six different solvent systems including N-methylmorpholine-N-oxide (NMMO), 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) ionic liquid (ILS), dimethylacetamide/lithium chloride (DMAc/LiCl), NaOH/urea, traditional copper(II)-ethylenediamine complex (CED) and CS₂/NaOH were employed respectively to dissolve cellulose and different uniform cellulose solutions were obtained. Steady state and dynamic rheological properties of different cellulose solutions were investigated under the same condition. The results showed that all cellulose solutions were pseudoplastic fluids and the apparent viscosity decreased with the increasing of shear rate. The cellulose solutions prepared by CED and CS₂/NaOH had the relatively good processing performance, however the destructive effect on cellulose macromolecules was relatively strong. The cellulose solutions obtained through NMMO and ILS dissolution had relatively inferior processing performance with relatively weak destructive effect on cellulose macromolecules. The processing properties of the cellulose solution and the destructive effect on cellulose macromolecules obtained from DMAc/LiCl and NaOH/Urea solvents were between the traditional solvent systems(CED and CS₂/NaOH) and new type of solvent systems (NMMO and ILS).