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H. SUZUKI¹, J. R. Giacin², and T. W. Downes². (1) TOPPAN Packaging Center, TOPPAN Printing Co., Ltd., 1-3-3 Suido Bunkyo-ku, Tokyo, 112-8531, Japan, (2) School of Packaging, Michigan State University, School of Packaging, Michigan State University, East Lansing, MI 48824-1223

The importance of modified polymeric materials for packaging purposes has been increasing due to their unique characteristics. Development of high barrier plastic films is a very important practical application for modified polymers. Ceramic (e.g., silicone oxide (SiOx) and aluminum oxide (Al2O3)) coating processes for the surface of polymeric films, have recieved considerable attention as surface modification techniques. Although ceramic-coated PET films exhibit good water vapor and oxygen gas barrier properties, the organic vapor (flavor or aroma moieties) permeability through ceramic-coated PET films has not been determined. Therefore, our objective was to determine the organic vapor (d-limonene and ethyl acetate) permeability of ceramic-coated PET films, under various test conditions, including: temperature and physical abuse levels. In order to obtain the permeability value of high barrier films, a dynamic purge and trap / thermal desorption procedure, with the MAS2000TM Permeation Test System was employed to achieve the required sensitivity levels. The permeance values of Al2O3-coated PET at 60 oC to d-limonene and ethyl acetate were 5.78 x 10-17 (kg/m2.sec.Pa) and 1.21 x 10-16 (kg/m2.sec.Pa), respectively. There is no major difference observed between the permeability through the Al2O3-coated PET film and that of the SiOx-coated PET film. From a comparison of the permeability of Al2O3-coated PET film to permeants under various conditions, polar permeants appeared to behave significantly differently from non-polar permeants, in terms of the mechanism of mass transfer. A simple model, which focuses on an interaction between permeants and coating defects, is proposed to account for the observed permeability behavior for the Al2O3-coated PET film. From this study, the first data of organic vapor permeability through Al2O3-coated PET film was obtained. Polarity of the permeants may significantly affect the permeation processes. A simple model was proposed to explain the permeation mechanism of Al2O3-coated PET films.