Yogurt Cup Recycling ? Effects of Different Washing Programs on VOC Emission
Sprache des Vortragstitels:
Englisch
Original Tagungtitel:
Polymer Meetings 15
Sprache des Tagungstitel:
Englisch
Original Kurzfassung:
Food is essential for life, but in order to ensure the distribution of goods and minimize losses we need packaging in enormous amounts. Nevertheless, there are several challenges to meet the requirements for bringing post consumer packaging waste (PCW) into circularity via mechanical recycling. This study focuses on the emission of volatile organic compounds (VOC) from separately collected PCW in form of yogurt cups, which could potentially migrate into the packed good. The sorted fractions of polystyrene (PS) and polypropylene (PP) were treated with different washing programs and processed into films to enable direct thermal desorption analysis. Resulting VOC values showed clearly lower VOC values for the PS fraction compared to PP. Moreover, a reduction in emission due to the increase of washing temperature and the addition of detergent was obtained and thus the relative washing efficiency got improved. An increase of the desorption temperature from 90°C to 130°C showed up to six times higher VOC values and also affected relative results. Furthermore, the components of the emissions identified by an mass spectroscopy library were categorized. In addition to identified external contaminations, both materials showed the highest contribution in emission in the categories of potential degradation products. Additionally, the expected migration values of detected substances were calculated and assessed according to the ?Union list of authorized substances? (EU No. 10/2011). The overall migration limits were not reached by far. However, some unlisted substances did exceed the specific migration limits and have to be further evaluated. Therefore, according to this study it is possible to rank different washing programs considering the resulting changes of VOC emission from recyclates. For the future, direct evaluation of emitted substances via thermal desorption analysis represents an interesting tool to give information about compliance for food contact materials.
Forschungs-