Conclusions on Multi-layer Packages

This calculation is possible by using a mathematical treatment in simple cases when the diffusivity is the same in the layers of the package. It is made by considering the method of separation of the variables of space and time. In other more complex cases when the values of the diffusivity are different from one layer to the other, a numerical method is employed. 

Food and Drug Administration, Points to Consider for the Use of Recycled Plastics Food Packaging, Chemistry Considerations, FDA Division of Food Chemistry and Technology publication HP 410, Washington, DC, USA, 1992. 

The Mathematics of Diffusion, 2nd Edition, Clarendon Press, Oxford, UK, 1975. 

Vergnaud, Liquid Transport Processes in Polymeric Materials, Prentice Hall, Englewood Cliffs, NJ, USA, 1991. 

Messadi, J.L. Taverdet and J-M. Vergnaud, Industrial and Engineering Chemistry Product Research and Development, 1983, 22, 1, 142. 

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