Cateto, CarolinaBarreiro, M.F.Belgacem, Mohamed NaceurRodrigues, Alírio2011-06-162011-06-162008Cateto, C.A.; Barreiro, M.F.; Belgacem, M.N.; Rodrigues, A.E. (2008). Size exclusion chromatography of lignin in N-N-dimethylformamide/lithium bromide. In 10th European Workshop on Lignocellulosics and Pulp. Stockholm, Sweden.http://hdl.handle.net/10198/5230The understanding of the macromolecular properties of lignin requires information on its molecular weight distributions. Size exclusion chromatography using DMF/LiBr as the mobile phase and PS-DVB gels as the stationary phase is a widely used system. In this study, two different lignin samples, Indulin-AT and Alcell, were analysed under different experimental conditions. The effect of temperature (60 and 80 ºC), LiBr concentration (0.1 and 0.9%, w/w) and sample preparation conditions (lignin concentration and dissolution time prior to analysis) were analysed. The influence of temperature and ionic strength on a polystyrene-based calibration curve was also studied. The two lignin samples have shown a distinct behaviour. Moreover, Alcell lignin in DMF/LiBr was found to be a viable model system to perform molecular weight investigations, particularly, those dealing with comparative studies with different molecular weight characterization techniques. With the addition of LiBr to DMF a unimodal MWD and an elution profile independent of sample concentration and used dissolution time was obtained. Moreover, a linear concentration dependence as a function of the UV response was observed.engLigninSECDMF-LiBrMolecular weightconference poster