Analysis of recycled PET bottles products by pyrolysis-gas chromatography

The impact of the contaminants in post used PET bottles on the decomposition of polymer itself after recycling process was analyzed. For that reason sorption experiments of harmful substances to PET bottles were performed. In order to monitor the presence of contaminants in recycled PET and evolution of thermal decomposition products of samples: virgin PET, contaminated PET flakes (PET K) and recycled PET (PET RM) were studied. The thermal degradation products of PET were achieved by pyrolysis using Pyrolysis-Gas Chromatography/Mass Spectrometry (Py-GC/MS), temperature-programmed evolved gas analysis-mass spectrometry (EGA-MS) and thermogravimetric analysis (TGA). Reactive pyrolysis with tetramethyl ammonium hydroxide (TMAH) was also performed to gather additional information about degradation products in studied samples. The pyrolysis products analysis of the studied PET samples indicate some changes in decomposition mechanism of PET samples that pass through contamination process due to some diversity in their chemical and structural composition.