DIELECTRIC-RELAXATION OF POROUS GLASSES

The dielectric properties of porous glasses, obtained from sodium boro silicate glass, were investigated in the frequency range 20 Hz to 1 MH z and temperature range -100 degrees C to +300 degrees C for the purpo se of inferring the geometric properties of porous materials. The feat ures of the dielectric properties due to the geometrical disorder were analysed by using models describing the non-Debye slow decay dynamics . The dielectric response is affected by the geometrical micro- and me sostructural properties of the porous matrix and the properties of the material filling the pores. It provides information on the hindered d ynamics of water molecules, located within the pores and affected by t he surfaces. An analysis of the dielectric parameters enables us to de scribe the porosity of the materials. (C) 1998 Elsevier Science B.V. A ll rights reserved.