WATER-VAPOR PERMEATION OF AQUEOUS BASED ETHYLACRYLATE METHYLMETHACRYLATE COPOLYMER FILMS

The water vapour permeation rate of isolated films consisting of Eudragit NE 30 D was found to be dependent on the film composition, film thickness, isolation technique and thermal treatment. The temperature during the experiments appeared to influence dramatically the water vapour permeation rate. With increasing temperature, the water permeation rate of the film increased. It was shown that Fick's law was not obeyed for water vapour permeation of aqueous based Eudragit NE 30 D films, indicating that investigating different film compositions at one thickness leads to erroneous conclusions.