The influence of humidity on the dielectric properties of wood

The dielectric behaviour of wood is strongly dependent on moisture content, density and structural anisotropy of the wood sample. The authors report on a dielectric study of wood samples by means of the thermally stimulated depolarization currents (TSDC) method. This method offers a powerful dielectric technique for the investigation of relaxation processes. It may provide useful information concerning the relaxing entities, the fraction of bound water and the hydration mechanisms. Moreover, TSDC measurements with special electrode configurations help to understand the origin of the individual peaks concerning their dipolar or spacecharge nature. They endeavour to elucidate the role of the water of hydration and to understand the microscopic mechanisms responsible for the observed characteristics, particularly in connection with elastic, acoustical and dielectric properties of wood