PREDICTION OF OXYGEN-TRANSPORT PARAMETERS OF PLASTIC PACKAGING MATERIALS FROM TRANSIENT STATE MEASUREMENTS

It was the objective of this research project to find reliable methods which allow the prediction of steady stare oxygen transmission from t ransient state measurements. Therefore, two models were tested, one us ing nonlinear regression analysis in combination with an equation desc ribing the transient state, the other wing a partial pressure pulse in stead of a constant change in partial pressure. The applicability of b oth methods in combination with a standard oxygen transmission rate te st equipment has been checked for different monolayers and multilayers . With the help of these methods the test procedure can be shortened. More detailed information of the permeation process is given by the fu ndamental diffusion and solubility coefficients which are calculated w ith the methods. Both models are valid only for ideal diffusion. Some factors are described that lead to deviations from ideal conditions an d influence the results.