During the lifetime polymers can emit degradation products and additives to the surrounding environment. The development of analytical techniques to identify and quantify migrated compounds is essential to assess the safety of the plastic products. This is especially important when plastic materials are used in demanding or otherwise sensitive applications such as toys, medical products, food packaging or water pipes as well as when new types of polymeric materials such as nanocomposites, degradable materials, functional materials or recycled materials are developed. We have in several studies applied chromatographic and mass spectrometric techniques for analysis of emissions from different polymeric materials. As an example we have shown that microwave heating can lead to accelerated degradation of additives incorporated in the polypropylene (PP)packages, which further led to increased migration of potentially toxic degradation products into the food . Significant antioxidant degradation was shown to take place during microwave heating of the packages in the fatty food simulants, while no degradation of antioxidants was detected during conventional heating of the packages in the fatty food simulants. No antioxidant degradation was observed in aqueous food simulants. Antioxidant migration rates from three PPmaterials to fatty food simulants differed largely with respect to the PP type and increased with decreasing degree of crystallinity in the materials . Stereocomplexation improved the migration resistance of novel polylactide based packaging materials in contact with food simulants . When polymeric materials are recycled one point of concern is the presence of unknown low molecular weight products in the materials. In addition the recycled materials could be more susceptible for further degradation even when further stabilized. We have shown that increasing amounts of degradation products are formed during aging of in-plant recycling of polyamide 6.6. The amount of degradation products could also be correlated to deterioration of material properties such as mechanical properties. The odor coming polypropylene materials containing recycled milled phenol-formaldehyde glass-fiber scrap was shown to be caused by the presence of phenol in the materials .
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ICFPAM 2011, 11th International Conference on Frontiers of Polymers and Advanced Materials. South Africa. 22 - 27 May 2011