WHITE PAPER NON-FICKIAN BEHAVIORS OF METALIZED FILMS AT HIGHER RELATIVE HUMIDITY LEVELS AMETEK MOCON April 2024 Content: Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Issues with Testing Metalized Films . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 What is Non-Fickian Behavior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Review of Historical Study of Metalized Film . . . . . . . . . . . . . . . . . . . . 2-3 Studies on Two Types of Metalized Films . . . . . . . . . . . . . . . . . . . . . . 3-4 Conclusions and Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

WHAT IS NON-FICKIAN BEHAVIOR AND WHY IS IT A PROBLEM? WHITE PAPER What is Non-Fickian Behavior? Due to their high barrier properties, mono-polymer metalized films are often used for traditional as well as sustainable packaging materials. Based on polyolefin substrates, they are considered recyclable when the thin layer of coating contains very little amount of metalization. For various applications, the metalized films should be examined for their barrier properties, particularly for water vapor transmission rate (WVTR). However, both historically and today, obtaining repeatable WVTR values for...

HISTORICAL AND RECENT STUDIES ON METALIZED FILMS WHITE PAPER quantified. The study was conducted at 37.8°C with 50%, 75%, 90% and 100% RH. For comparison, a calculated Fickian behavior curve (based on 50% RH tested value) is also included in the graph (Fig. 3). When compared with the predicted Fickian response as shown in Fig. 3, the material clearly acted in a non-Fickian manner. The WVTR value almost doubled from 90% RH to 100% RH. The WVTR test result at 100% RH was nearly 10 times of the calculated data if the material would be Fickian. This means that higher RH conditions had a greater impact...

FURTHER RESEARCH ON METALIZED FILMS REVEALS USEFUL DATA WHITE PAPER BOPP, on the other hand, is non-polar and hydrophobic, making it more stable under moderate levels of moisture. This film started showing non-Fickian behavior at higher RH challenges, which may be due to some unrecognized synergy between the metalized layer and higher moisture. Due to the above reasons and observations, it is critical to analyze WVTR at the actual RH for metalized films. It is not encouraged to test WVTR at one level and then extrapolate WVTR to other RH levels. For comparison testing of these metalized films,...