• Kuusipalo, Jurkka
• Lahti, Johanna
• Johansson, Petri Tapio

Abstract

Controlling of moisture and oxygen permeation through the packaging material is essential in most packaging applications. With multilayer structures of different barrier materials, there is possibility to create desired barrier properties to the package. The challenge is to plan appropriate barrier level, e.g. WVTR and OTR, theoretically to the package before producing the package. Furthermore, in specific packages there is a need to control the permeation e.g. respiration in vegetable packages. Typically foils and polymer films have high barrier properties, therefore, permeation can be controlled by producing artificial pinholes in these kinds of packages.<br/><br/>Influence of artificial pinholes in aluminium foils and plastic films on water vapour and oxygen permeation was determined in this study. Results show clear correlation between the size and number of pinholes and gas permeation. Water vapour and oxygen permeation increase significantly when there are pinholes through the structure. It was observed that the greater the RH difference between inside and outside the sample in WVTR measurement, the greater the permeation was through the pinholes. Additionally, it was found that the effect of pinholes on the oxygen permeation on aluminium foil can almost be eliminated by using polyethylene coating on top of aluminium foil.

Topics

• impedance spectroscopy
• polymer
• Oxygen
• aluminium