In this thesis, we wanted to demonstrate the degradation of plastics by fungi. We used surgical masks made of polypropylene and wanted to degrade them with Aspergillus niger, Trametes versicolor and Pleurotus ostreatus during 16 weeks of exposure. The samples were prepared in two ways: by cutting to a size of 2 × 7 cm and by grinding using dry ice. Half of the cut samples were exposed to UV light for 168 hours before exposure to the fungi. The objectives of the thesis were to demonstrate that certain fungi are capable of degrading polypropylene and that UV pre-treatment enhances degradation. The results of the FT-IR analysis showed reduced signals between the wavenumbers 3000 and 2800 cm-1 and around the wavenumber 1000 cm-1, indicating the onset of degradation of the CH groups of polypropylene. The tensile strength results showed that the fungi Aspergillus niger and Pleurotus ostreatus successfully reduced the tensile strength of the middle, weakest layer, and UV light successfully reduced the tensile strength of the middle layer. When measuring the density of the sample as a porous material with the GeoPyc device, the control samples pre-treated with UV light had a lower density than the control samples without UV pre-treatment. We have shown that certain fungi are able to degrade polypropylene and that UV pre-treatment helps to degrade polypropylene.
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