Relationship between Water Absorption and Dielectric Behavior of Glass Fiber Reinforced Unsaturated Polyester Resin

ALICIA FRAGA,; E. FRULLONI; ORLANDO DE LA OSA,; J M KENNY; ANALIA VAZQUEZ

JOURNAL OF COMPOSITE MATERIALS

SAGE Publications

Año: 2007 vol. 41 p. 393 - 402

0021-9983

Water uptake at 25ºC is measured for unsaturated polyester matrix and glass fiber composites as a function of time. Dielectric measurement in the frequency range of 1 MHz–1GHz has been performed on the specimens during the water absorption process. The dielectric constant decreases as the frequency increases for matrix and composites. The dielectric constant of unsaturated polyester is lower than their composites based on glass fibers. A Fickian diffusion model is applied for water absorption studies, and the effective diffusion coefficient is calculated for each sample. An empirical model describing the increase in dielectric constant with water absorption is proposed.