Publicação
Size exclusion chromatography of lignin in N-N-dimethylformamide/lithium bromide
| Resumo: | The 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. |
|---|---|
| Autores principais: | Cateto, Carolina |
| Outros Autores: | Barreiro, M.F.; Belgacem, Mohamed Naceur; Rodrigues, Alírio |
| Assunto: | Lignin SEC DMF-LiBr Molecular weight |
| Ano: | 2008 |
| País: | Portugal |
| Tipo de documento: | comunicação em conferência |
| Tipo de acesso: | acesso restrito |
| Instituição associada: | Instituto Politécnico de Bragança |
| Idioma: | inglês |
| Origem: | Biblioteca Digital do IPB |
| Resumo: | The 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. |
|---|