Molecular weight dependence and stereoselective chain cleavage during the early stages of the isotactic polypropylene pyrolysis

The comparative study on the pyrolysis of two Polypropylene samples, with a similar high isotactic character but quite distinct molecular weights, reveals a significant difference in their thermal performances. The detailed qualitative analysis of the parameters, which are expected to govern the thermal degradation, leads to reasonably assume a main role of the molecular weight in their relative early stabilities. Furthermore, the correlation found between the sharp initial build-up of the Eact and the selective cleavage of isotactic stereosequences in both samples, suggests the relevance of the stereoregular length into the energy required for chain scissionThe authors acknowledge the financial support of project MAT2016-79869-C2-1-P (AEI/FEDER, UE), as well as the kindly assistance of Repsol for the supply of samples.Peer reviewe