Conformation and dn/dc determination of cellulose in N,N-dimethylacetamide containing lithium chloride

In order to characterise cellulose dissolved in lithium chloride/N,N-dimethylacetamide (LiCl/DMAc) using size-exclusion chromatography with online multiangle laser light scattering and differential refractive index detection, a number of parameters were determined. One of them in particular, the specific refractive index increment (dn/dc) of cellulose in 0.5% LiCl/DMAc, is required in order to calculate the molar mass from the light scattering signal. Pure cellulose paper was used as sample source. The precision and reproducibility of the SEC/MALS/DRI method were evaluated. Molar mass and root mean square radii averages, molar mass distribution as well as conformation of cellulose in 0.5% LiCl/DMAC, from both unaged and artificially aged papers, were studied. The latter was determined to be random coil for cellulose and vary slightly with the polymer molar mass. (C) 2004 Elsevier Ltd. All rights reserved.