Molecular mobility of poplar cell wall polymers studied by dielectric techniques

In this work, thermally stimulated currents (TSC) analyzes combined with dynamic dielectric spectroscopy (DDS) have been applied to the investigation of polymers’ molecular mobility involves in poplar cell wall. The molecular origin of the various dielectric relaxations has been determined. Cellulose and lignin effects in wood dielectric response were distinguished. The correlation between results obtained by both dielectric methods allows us to follow molecular mobility involved in delocalized movement as primary relaxation mode. For these two major components of wood, the evolution of relaxation times involve in α-relaxation mode is explained using the strong/fragile pattern. We compared the cellulose and lignin in situ and ex situ responses to interpret wood compound behavior. The importance of structural wood interactions which modified the molecular mobility of polymer components will be underlined.