اثر بلورينگي بر مهاجرت مواد سبك از پلي اتيلن سنگين به ماده غذايي چرب

Crystallinity Effect on Migration of Low Molecular Weight Substances from HDPE into Fatty Food

Migration, a mass transfer process by which low molecular weight substances are released from package into the contained foodstuff. Regulatory control of the process is of utmost importance in plastic food packaging. Different parameters such as the type of polymer, food, migrants, contact conditions, physical properties of the polymer, etc. affect the rate and amount of migratory substances. Morphology and crystallinity of the packaging material should have great effect on this migration. However, a few works have been dedicated to this item and its impact on the regulatory controls of food packaging is not well established. In this research the effect of substances from the polymer packaging into the foodstuff is studied. For this, the samples have been prepared from HDPE by injection moulding and compression moulding. The degrees of crystallinity of the samples are determinated by DSC. The samples are exposed to fatty food stimulants (ethanol solution 95%) under a defined condition (time/temperature). After the period of test, the samples are dried and weighed and the relationship between the weight loss and the degree of crystallinity are studied.