Effect of lay-up on the sorption behaviour of woven glass-polyester composites

The effects of the lay-up on the water diffusion behaviour of hand made woven glass/polyester composites have been investigated by means of sorption experiments and numerical simulation of the diffusion process in a stratified media. Experimental sorption curves exhibited a non linear behaviour during the initial sorption step. On the basis of the numerical simulations, this behaviour was attributed to an enhanced diffusion rate in the superficial matrix layers. These effects were found to affect significantly the measurement of the diffusion coefficient from the sorption curve.