Molmassenverteilung cellulosischer produkte mittels Grössenausschlusschromatographie in DMAc/LiCl

The dissolution system N,N-dimethylacetamide/lithlum chloride (DMAc/LiCl) is reported in the literature to be a suitable eluent for the determination of the molecular mass distribution of cellulosic substrates by size exclusion chromatography (SEC). This article deals with fundamental and practical issues concerning this method. After the description of the applied chromatographic system and the processing of the data gained by the coupled light scattering detector (MALLS) the influence of different techniques of cellulose activation and dissolution is discussed considering various cellulose samples like high and low molecular weight pulp and viscose fiber. Furthermore, results of dynamic light scattering experiments in the concentration range of SEC samples are presented with regard to the state and molecular dispersion of the sample solutions. Typical applications of this SEC-MALLS method of cellulose in DMAc/LiCl are discussed. Preliminary results of an interlaboratory comparison of different SEC methods for the determination of the molecular mass distribution of cellulose give some information on the current state of diversity of results of different research groups.