Absorption Coefficients as Indicators of Barrier Properties of Packaging Films, 1998 Polymers, Laminations & Coatings Conference Proceedings

Oxygen and water vapor permeation rates through polymers have been routinely measured for many years. Because rates are relatively high and the concentrations are easily maintained at high levels, the results for these permeants are obtained in a reasonably short time period and subsequently used for material selection. However, if a polymer shows a high degree of barrier to a permeant, the rate of permeation is extremely slow. Accurate measurements can take weeks, or even months before a steady state condition is reached as well as engage both manpower and machine time over that period of time.

This paper will report on the use of desorption curves to obtain information on barrier properties. Procedures are used that reduce the time required to evaluate polymer interactions with flavor and aroma permeants. In this study, acrylonitrile copolymers are compared to other polymers to investigate their scalping properties and give more information on their barrier properties.