On Migration Of Pollutant In Recycled Plastics Applied In Food Packaging

Pressures to utilize recycled plastics in food packaging have increasedsince use of landfills and incineration cannot be the ultimate solutions to thesolid waste problem and employ resource is lacking. But lack of knowledge ofthe substances present in the recycled plastics has been an obstacle for theapplication of recycled plastics for food packaging. In order to resolve thisproblem there must be find the transferred disciplinarian of pollutant inrecycled plastics and migration influence on some parameters (barrier thickness,temperature, diffusion and partition coefficient etc.)One purpose of this research is to develop a computer program that can beutilized to predict the adequacy of a functional barrier structure in preventingmigration of undesirable constituents in recycled plastics into liquid productssuch as foods. A simulation model computer program, which accounts for not onlythe diffusion process inside the polymer but also partitioning of the contaminantbetween the polymer and the contacting phase, was developed based on a numericaltreatment, the finite element method, to quantify the migration through themulti-layer structures. The accuracy of the model in predicting migration wasdemonstrated successfully by comparing the simulated results to experimentaldata. The computer program, developed as a total solution package for migrationproblems, can be applied not only to multi-layer structures made with the sametype of plastics, but also to structures with different plastics, e.g.PP/PE/PP.The other objective of this study is to determine precisely the effect ofthe thicknesses of barrier layer, the temperature, diffusion and partitioncoefficient etc. This work might provide the potential for wider use of recycledplastic, especially polyolefins which have less barrier ability, in foodpackaging.