Size-Exclusion Chromatography and Aggregation Studies of Acetylated Lignins in N,N-Dimethylacetamide in the Presence of Salts

摘要

The molar masses of acetylated kraft lignin and organosolv lignin are determined using both dynamic light scattering and size-exclusion chromatography (SEC). Preparative gel fractionation of both lignins is allowed for the further analysis of low-polydispersity lignin fractions. Fundamental information about the aggregation behavior of different molecular weight lignins in different solvent systems is provided. Two different solvent systems are used for SEC. Universal calibration is used for analysis. Applying the Flory-Fox theory, the obtained molecular weights are allowed for determining the maximum glass transition temperature at theoretical infinite molecular weight, T-g, of both acetylated lignins.