A Comparative Study of Water Absorption Theories Applied to Glass Epoxy Composites

Three types of glass epoxy composites have been studied and water diffu sion leading to saturation has been shown to occur under humid conditions for two of them, the third composite was seen to degrade in the presence of water. It has been found necessary to apply two different models of diffusion to explain the behavior of the first two materials. Both of the theoretical models are based on Fick's law, the first being classical single phase diffusion and the second is a two phase model for the Langmuir type. The material tested were identical except for the resin hardeners which were used which were, diamine, dicyandiamide, and anhydride. The testing conditions, were 0%-100% Relative humidity and 25°C-90°C.