On the microstructure of polypropylenes by pyrolysis GC-MS

In this work the pyrolysis products of various Polypropylenes (PP) have been identified in terms of structure and isomerism. The different microstructure of Polypropylenes reflected in the pyrolysis products provides a fingerprint which can be used to asses the origin of the different polymers. The distinction amongst various PP was possible through the quantitative analysis of the main pyrolysis products: 1-alkene pentamers, hexamers and heptamers. After individuation and quantification of these products, a statistic study through the Principal Components Analysis allowed to separate syndio and atactic Polypropylenes as well as isotactic Polypropylenes of different origin. The results of this study can be used in various fields, for example in forensic and commodities analyses or in quality control.