Cellulose, a biopolymer of great importance to the fiber and paper industries, is difficult to characterize because of its high molar mass. Its intractable nature means it cannot be dissolved in conventional solvents without chemical modification. With tedious effort, it can be modified so that it can be dissolved in an easy-to-use solvent like THF, but when the cellulose is so-modified it is degraded and the analysis does not represent the source material.
Unmodified cellulose can be dissolved in dimethyl acetamide (DMAC) with LiCl added. The problem remains, how to characterize it without reference to column calibration standards that typically do not have the same conformation as cellulose and therefore do not provide accurate calibration curves. Absolute characterization is performed by combining multi-angle light scattering with size exclusion chromatography (SECMALS) to determine molar mass, independently of elution standards.
