Recycled plastics covered by functional barriers

Concerning the efficiency definition of a functional barrier, different understandings seem to exist. On the one hand and in most of the published cases in the litera- 

From the above discussion, one can summarize that functional barrier efficiency does not correspond to an absolute barrier requirement but is related to a functional quantity in terms of mass transfer which is dependent of the technological and application-related parameters of the respective food-packaging system. These parameters are  

Currently, there are two different test principles which have been described and applied in practice  

Migration testing of deliberately contaminated packaging structures using incorporated model contaminants or surrogates. 

Migration testing of real-life recycling packaging structures by monitoring inherently present recycling-related substances. 

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