WATER-ABSORPTION OF A DIGLYCIDYL ETHER OF BISPHENOL A 1,3-BISAMINOMETHYLCYCLOHEXANE (DGEBA/1,3-BAC) EPOXY-RESIN SYSTEM/

The diffusive and dynamic mechanical behavior of the DGEBA/1,3-BAC epo xy resin system was studied during water absorption. The diffusion of water was investigated at 100% relative humidity, by immersion of spec imens in water at 60, 80 and 100 degrees C. in all absorption experime nts, water diffusion followed Fick's law. Diffusion coefficients and s aturated water concentrations are given for these temperatures. The ac tivation energy for diffusion was determined from the relationship bet ween the diffusion coefficient and the reciprocal of the absolute temp erature. The value obtained was 31.2 kJ mol(-1). Dynamic mechanical an alysis of samples immersed in 100 degrees C water and with various wat er contents showed both a shift of T-g, defined by the tan delta peak, to lower temperatures and a slight decrease in the dynamic modulus in the presence of water. These effects are probably a result of plastic ization.