Abstract
Viscosity measurements of cellulose in SO2-diethylamine-dimethylsulfoxide were studied in order to examine the applicability of this cellulose solvent system for molecular weight measurement of cellulose in wood pulp.
Microcrystalline cellulose powder, pulp for filter paper, bleached kraft pulp, linter, cotton and low molecular weight regenerated cellulases are dissolved rapidly in this system. Limiting viscosity numbers were obtained from the Huggins plots, and the relationship between the limiting viscosity numbers and the concentrations of cellulose was proposed. The Mark-Houwink-Sakurada equations for cellulose in SO2-diithylamine-dimethylsulfoxide corresponding to those in cupriethylenediamine hydroxide were proposed. The parameters a in the equations are 1.04-1.23, which means that cellulose chains expand in the dissolution state.
Although the cellulose/SO2-diethylamine-dimethylsulfoxide solution is not stable for long time, this cellulose solvent system is applicable to evaluation of molecular weight of cellulose in wood pulp because cellulose sample are dissolved in this system very rapidly without degradations.
